Although we have several data csum verification code, we never have a
function really just to verify checksum for one sector.
Function check_data_csum() do extra work for error reporting, thus it
requires a lot of extra things like file offset, bio_offset etc.
Function btrfs_verify_data_csum() is even worse, it will utilize page
checked flag, which means it can not be utilized for direct IO pages.
Here we introduce a new helper, btrfs_check_sector_csum(), which really
only accept a sector in page, and expected checksum pointer.
We use this function to implement check_data_csum(), and export it for
incoming patch.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[hch: keep passing the csum array as an arguments, as the callers want
to print it, rename per request]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This reverts commit 253bf57555.
Revert the xarray conversion, there's a problem with potential
sleep-inside-spinlock [1] when calling xa_insert that triggers GFP_NOFS
allocation. The radix tree used the preloading mechanism to avoid
sleeping but this is not available in xarray.
Conversion from spin lock to mutex is possible but at time of rc6 is
riskier than a clean revert.
[1] https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/
Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This reverts commit 8ee922689d.
Revert the xarray conversion, there's a problem with potential
sleep-inside-spinlock [1] when calling xa_insert that triggers GFP_NOFS
allocation. The radix tree used the preloading mechanism to avoid
sleeping but this is not available in xarray.
Conversion from spin lock to mutex is possible but at time of rc6 is
riskier than a clean revert.
[1] https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/
Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This reverts commit 48b36a602a.
Revert the xarray conversion, there's a problem with potential
sleep-inside-spinlock [1] when calling xa_insert that triggers GFP_NOFS
allocation. The radix tree used the preloading mechanism to avoid
sleeping but this is not available in xarray.
Conversion from spin lock to mutex is possible but at time of rc6 is
riskier than a clean revert.
[1] https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/
Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When replacing file extents, called during fallocate, hole punching,
clone and deduplication, we may not be able to replace/drop all the
target file extent items with a single transaction handle. We may get
-ENOSPC while doing it, in which case we release the transaction handle,
balance the dirty pages of the btree inode, flush delayed items and get
a new transaction handle to operate on what's left of the target range.
By dropping and replacing file extent items we have effectively modified
the inode, so we should bump its iversion and update its mtime/ctime
before we update the inode item. This is because if the transaction
we used for partially modifying the inode gets committed by someone after
we release it and before we finish the rest of the range, a power failure
happens, then after mounting the filesystem our inode has an outdated
iversion and mtime/ctime, corresponding to the values it had before we
changed it.
So add the missing iversion and mtime/ctime updates.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The btrfs_dio_private structure is only used in inode.c, so move the
definition there.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add a wrapper around iomap_dio_rw that keeps the direct I/O internals
isolated in inode.c.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Several functions take parameter bio_flags that was simplified to just
compress type, unify it and change the type accordingly.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The parameter has been added in 2009 in the infamous monster commit
5d4f98a28c ("Btrfs: Mixed back reference (FORWARD ROLLING FORMAT
CHANGE)") but not used ever since. We can sink it and allow further
simplifications.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
… rename it to simply fs_roots and adjust all usages of this object to use
the XArray API, because it is notionally easier to use and understand, as
it provides array semantics, and also takes care of locking for us,
further simplifying the code.
Also do some refactoring, esp. where the API change requires largely
rewriting some functions, anyway.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Gabriel Niebler <gniebler@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
… named 'extent_buffers'. Also adjust all usages of this object to use
the XArray API, which greatly simplifies the code as it takes care of
locking and is generally easier to use and understand, providing
notionally simpler array semantics.
Also perform some light refactoring.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Gabriel Niebler <gniebler@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
… in the btrfs_root struct and adjust all usages of this object to use
the XArray API, because it is notionally easier to use and understand,
as it provides array semantics, and also takes care of locking for us,
further simplifying the code.
Also use the opportunity to do some light refactoring.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Gabriel Niebler <gniebler@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
rmw_workers doesn't need ordered execution or thread disabling threshold
(as the thresh parameter is less than DFT_THRESHOLD).
Just switch to the normal workqueues that use a lot less resources,
especially in the work_struct vs btrfs_work structures.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All three scrub workqueues don't need ordered execution or thread
disabling threshold (as the thresh parameter is less than DFT_THRESHOLD).
Just switch to the normal workqueues that use a lot less resources,
especially in the work_struct vs btrfs_work structures.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Just let the one caller that wants optional WQ_HIGHPRI handling allocate
a separate btrfs_workqueue for that. This allows to rename struct
__btrfs_workqueue to btrfs_workqueue, remove a pointer indirection and
separate allocation for all btrfs_workqueue users and generally simplify
the code.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Both btrfs_repair_one_sector and submit_bio_one as the direct caller of
one of the instances ignore errors as they expect the methods themselves
to call ->bi_end_io on error. Remove the unused and dangerous return
value.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Keep btrfs_readpage next to btrfs_do_readpage and the other address
space operations. This allows to keep submit_one_bio and
struct btrfs_bio_ctrl file local in extent_io.c.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we use a spin lock to protect the red black tree that we use to
track block groups. Most accesses to that tree are actually read only and
for large filesystems, with thousands of block groups, it actually has
a bad impact on performance, as concurrent read only searches on the tree
are serialized.
Read only searches on the tree are very frequent and done when:
1) Pinning and unpinning extents, as we need to lookup the respective
block group from the tree;
2) Freeing the last reference of a tree block, regardless if we pin the
underlying extent or add it back to free space cache/tree;
3) During NOCOW writes, both buffered IO and direct IO, we need to check
if the block group that contains an extent is read only or not and to
increment the number of NOCOW writers in the block group. For those
operations we need to search for the block group in the tree.
Similarly, after creating the ordered extent for the NOCOW write, we
need to decrement the number of NOCOW writers from the same block
group, which requires searching for it in the tree;
4) Decreasing the number of extent reservations in a block group;
5) When allocating extents and freeing reserved extents;
6) Adding and removing free space to the free space tree;
7) When releasing delalloc bytes during ordered extent completion;
8) When relocating a block group;
9) During fitrim, to iterate over the block groups;
10) etc;
Write accesses to the tree, to add or remove block groups, are much less
frequent as they happen only when allocating a new block group or when
deleting a block group.
We also use the same spin lock to protect the list of currently caching
block groups. Additions to this list are made when we need to cache a
block group, because we don't have a free space cache for it (or we have
but it's invalid), and removals from this list are done when caching of
the block group's free space finishes. These cases are also not very
common, but when they happen, they happen only once when the filesystem
is mounted.
So switch the lock that protects the tree of block groups from a spinning
lock to a read/write lock.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We keep track of the start offset of the block group with the lowest start
offset at fs_info->first_logical_byte. This requires explicitly updating
that field every time we add, delete or lookup a block group to/from the
red black tree at fs_info->block_group_cache_tree.
Since the block group with the lowest start address happens to always be
the one that is the leftmost node of the tree, we can use a red black tree
that caches the left most node. Then when we need the start address of
that block group, we can just quickly get the leftmost node in the tree
and extract the start offset of that node's block group. This avoids the
need to explicitly keep track of that address in the dedicated member
fs_info->first_logical_byte, and it also allows the next patch in the
series to switch the lock that protects the red black tree from a spin
lock to a read/write lock - without this change it would be tricky
because block group searches also update fs_info->first_logical_byte.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reading a value from a different member of a union is not just a great
way to obfuscate code, but also creates an aliasing violation. Switch
btrfs_is_zoned to look at ->zone_size and remove the union.
Note: union was to simplify the detection of zoned filesystem but now
this is wrapped behind btrfs_is_zoned so we can drop the union.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note ]
Signed-off-by: David Sterba <dsterba@suse.com>
When doing a NOWAIT direct IO write, if we can NOCOW then it means we can
proceed with the non-blocking, NOWAIT path. However reserving the metadata
space and qgroup meta space can often result in blocking - flushing
delalloc, wait for ordered extents to complete, trigger transaction
commits, etc, going against the semantics of a NOWAIT write.
So make the NOWAIT write path to try to reserve all the metadata it needs
without resulting in a blocking behaviour - if we get -ENOSPC or -EDQUOT
then return -EAGAIN to make the caller fallback to a blocking direct IO
write.
This is part of a patchset comprised of the following patches:
btrfs: avoid blocking on page locks with nowait dio on compressed range
btrfs: avoid blocking nowait dio when locking file range
btrfs: avoid double nocow check when doing nowait dio writes
btrfs: stop allocating a path when checking if cross reference exists
btrfs: free path at can_nocow_extent() before checking for checksum items
btrfs: release path earlier at can_nocow_extent()
btrfs: avoid blocking when allocating context for nowait dio read/write
btrfs: avoid blocking on space revervation when doing nowait dio writes
The following test was run before and after applying this patchset:
$ cat io-uring-nodatacow-test.sh
#!/bin/bash
DEV=/dev/sdc
MNT=/mnt/sdc
MOUNT_OPTIONS="-o ssd -o nodatacow"
MKFS_OPTIONS="-R free-space-tree -O no-holes"
NUM_JOBS=4
FILE_SIZE=8G
RUN_TIME=300
cat <<EOF > /tmp/fio-job.ini
[io_uring_rw]
rw=randrw
fsync=0
fallocate=posix
group_reporting=1
direct=1
ioengine=io_uring
iodepth=64
bssplit=4k/20:8k/20:16k/20:32k/10:64k/10:128k/5:256k/5:512k/5:1m/5
filesize=$FILE_SIZE
runtime=$RUN_TIME
time_based
filename=foobar
directory=$MNT
numjobs=$NUM_JOBS
thread
EOF
echo performance | \
tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
umount $MNT &> /dev/null
mkfs.btrfs -f $MKFS_OPTIONS $DEV &> /dev/null
mount $MOUNT_OPTIONS $DEV $MNT
fio /tmp/fio-job.ini
umount $MNT
The test was run a 12 cores box with 64G of ram, using a non-debug kernel
config (Debian's default config) and a spinning disk.
Result before the patchset:
READ: bw=407MiB/s (427MB/s), 407MiB/s-407MiB/s (427MB/s-427MB/s), io=119GiB (128GB), run=300175-300175msec
WRITE: bw=407MiB/s (427MB/s), 407MiB/s-407MiB/s (427MB/s-427MB/s), io=119GiB (128GB), run=300175-300175msec
Result after the patchset:
READ: bw=436MiB/s (457MB/s), 436MiB/s-436MiB/s (457MB/s-457MB/s), io=128GiB (137GB), run=300044-300044msec
WRITE: bw=435MiB/s (456MB/s), 435MiB/s-435MiB/s (456MB/s-456MB/s), io=128GiB (137GB), run=300044-300044msec
That's about +7.2% throughput for reads and +6.9% for writes.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At btrfs_cross_ref_exist() we always allocate a path, but we really don't
need to because all its callers (only 2) already have an allocated path
that is not being used when they call btrfs_cross_ref_exist(). So change
btrfs_cross_ref_exist() to take a path as an argument and update both
its callers to pass in the unused path they have when they call
btrfs_cross_ref_exist().
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In order for end users to quickly react to new issues that come up in
production, it is proving useful to leverage this printk indexing
system. This printk index enables kernel developers to use calls to
printk() with changeable ad-hoc format strings, while still enabling end
users to detect changes and develop a semi-stable interface for
detecting and parsing these messages.
So that detailed Btrfs messages are captured by this printk index, this
patch wraps btrfs_printk and btrfs_handle_fs_error with macros.
Example of the generated list:
https://lore.kernel.org/lkml/12588e13d51a9c3bf59467d3fc1ac2162f1275c1.1647539056.git.jof@thejof.com
Signed-off-by: Jonathan Lassoff <jof@thejof.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have four different scenarios where we don't expect to find ordered
extents after locking a file range:
1) During plain fallocate;
2) During hole punching;
3) During zero range;
4) During reflinks (both cloning and deduplication).
This is because in all these cases we follow the pattern:
1) Lock the inode's VFS lock in exclusive mode;
2) Lock the inode's i_mmap_lock in exclusive node, to serialize with
mmap writes;
3) Flush delalloc in a file range and wait for all ordered extents
to complete - both done through btrfs_wait_ordered_range();
4) Lock the file range in the inode's io_tree.
So add a helper that asserts that we don't have ordered extents for a
given range. Make the four scenarios listed above use this helper after
locking the respective file range.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All of our inode creation code paths duplicate the calls to
btrfs_init_inode_security() and btrfs_add_link(). Subvolume creation
additionally duplicates property inheritance and the call to
btrfs_set_inode_index(). Fix this by moving the common code into
btrfs_create_new_inode(). This accomplishes a few things at once:
1. It reduces code duplication.
2. It allows us to set up the inode completely before inserting the
inode item, removing calls to btrfs_update_inode().
3. It fixes a leak of an inode on disk in some error cases. For example,
in btrfs_create(), if btrfs_new_inode() succeeds, then we have
inserted an inode item and its inode ref. However, if something after
that fails (e.g., btrfs_init_inode_security()), then we end the
transaction and then decrement the link count on the inode. If the
transaction is committed and the system crashes before the failed
inode is deleted, then we leak that inode on disk. Instead, this
refactoring aborts the transaction when we can't recover more
gracefully.
4. It exposes various ways that subvolume creation diverges from mkdir
in terms of inheriting flags, properties, permissions, and POSIX
ACLs, a lot of which appears to be accidental. This patch explicitly
does _not_ change the existing non-standard behavior, but it makes
those differences more clear in the code and documents them so that
we can discuss whether they should be changed.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The various inode creation code paths do not account for the compression
property, POSIX ACLs, or the parent inode item when starting a
transaction. Fix it by refactoring all of these code paths to use a new
function, btrfs_new_inode_prepare(), which computes the correct number
of items. To do so, it needs to know whether POSIX ACLs will be created,
so move the ACL creation into that function. To reduce the number of
arguments that need to be passed around for inode creation, define
struct btrfs_new_inode_args containing all of the relevant information.
btrfs_new_inode_prepare() will also be a good place to set up the
fscrypt context and encrypted filename in the future.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of calling new_inode() and inode_init_owner() inside of
btrfs_new_inode(), do it in the callers. This allows us to pass in just
the inode instead of the mnt_userns and mode and removes the need for
memalloc_nofs_{save,restores}() since we do it before starting a
transaction. In create_subvol(), it also means we no longer have to look
up the inode again to instantiate it. This also paves the way for some
more cleanups in later patches.
This also removes the comments about Smack checking i_op, which are no
longer true since commit 5d6c31910b ("xattr: Add
__vfs_{get,set,remove}xattr helpers"). Now it checks inode->i_opflags &
IOP_XATTR, which is set based on sb->s_xattr.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a common pattern when searching for a key in btrfs:
* Call btrfs_search_slot to find the slot for the key
* Enter an endless loop:
* If the found slot is larger than the no. of items in the current
leaf, check the next leaf
* If it's still not found in the next leaf, terminate the loop
* Otherwise do something with the found key
* Increment the current slot and continue
To reduce code duplication, we can replace this code pattern with an
iterator macro, similar to the existing for_each_X macros found
elsewhere in the kernel. This also makes the code easier to understand
for newcomers by putting a name to the encapsulated functionality.
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Signed-off-by: Gabriel Niebler <gniebler@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-5.18-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- direct IO fixes:
- restore passing file offset to correctly calculate checksums
when repairing on read and bio split happens
- use correct bio when sumitting IO on zoned filesystem
- zoned mode fixes:
- fix selection of device to correctly calculate device
capabilities when allocating a new bio
- use a dedicated lock for exclusion during relocation
- fix leaked plug after failure syncing log
- fix assertion during scrub and relocation
* tag 'for-5.18-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: zoned: use dedicated lock for data relocation
btrfs: fix assertion failure during scrub due to block group reallocation
btrfs: fix direct I/O writes for split bios on zoned devices
btrfs: fix direct I/O read repair for split bios
btrfs: fix and document the zoned device choice in alloc_new_bio
btrfs: fix leaked plug after failure syncing log on zoned filesystems
Currently, we use btrfs_inode_{lock,unlock}() to grant an exclusive
writeback of the relocation data inode in
btrfs_zoned_data_reloc_{lock,unlock}(). However, that can cause a deadlock
in the following path.
Thread A takes btrfs_inode_lock() and waits for metadata reservation by
e.g, waiting for writeback:
prealloc_file_extent_cluster()
- btrfs_inode_lock(&inode->vfs_inode, 0);
- btrfs_prealloc_file_range()
...
- btrfs_replace_file_extents()
- btrfs_start_transaction
...
- btrfs_reserve_metadata_bytes()
Thread B (e.g, doing a writeback work) needs to wait for the inode lock to
continue writeback process:
do_writepages
- btrfs_writepages
- extent_writpages
- btrfs_zoned_data_reloc_lock(BTRFS_I(inode));
- btrfs_inode_lock()
The deadlock is caused by relying on the vfs_inode's lock. By using it, we
introduced unnecessary exclusion of writeback and
btrfs_prealloc_file_range(). Also, the lock at this point is useless as we
don't have any dirty pages in the inode yet.
Introduce fs_info->zoned_data_reloc_io_lock and use it for the exclusive
writeback.
Fixes: 35156d8527 ("btrfs: zoned: only allow one process to add pages to a relocation inode")
CC: stable@vger.kernel.org # 5.16.x: 869f4cdc73: btrfs: zoned: encapsulate inode locking for zoned relocation
CC: stable@vger.kernel.org # 5.16.x
CC: stable@vger.kernel.org # 5.17
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Primarily this series converts some of the address_space operations
to take a folio instead of a page.
->is_partially_uptodate() takes a folio instead of a page and changes the
type of the 'from' and 'count' arguments to make it obvious they're bytes.
->invalidatepage() becomes ->invalidate_folio() and has a similar type change.
->launder_page() becomes ->launder_folio()
->set_page_dirty() becomes ->dirty_folio() and adds the address_space as
an argument.
There are a couple of other misc changes up front that weren't worth
separating into their own pull request.
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Merge tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache
Pull filesystem folio updates from Matthew Wilcox:
"Primarily this series converts some of the address_space operations to
take a folio instead of a page.
Notably:
- a_ops->is_partially_uptodate() takes a folio instead of a page and
changes the type of the 'from' and 'count' arguments to make it
obvious they're bytes.
- a_ops->invalidatepage() becomes ->invalidate_folio() and has a
similar type change.
- a_ops->launder_page() becomes ->launder_folio()
- a_ops->set_page_dirty() becomes ->dirty_folio() and adds the
address_space as an argument.
There are a couple of other misc changes up front that weren't worth
separating into their own pull request"
* tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache: (53 commits)
fs: Remove aops ->set_page_dirty
fb_defio: Use noop_dirty_folio()
fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio
fs: Convert __set_page_dirty_buffers to block_dirty_folio
nilfs: Convert nilfs_set_page_dirty() to nilfs_dirty_folio()
mm: Convert swap_set_page_dirty() to swap_dirty_folio()
ubifs: Convert ubifs_set_page_dirty to ubifs_dirty_folio
f2fs: Convert f2fs_set_node_page_dirty to f2fs_dirty_node_folio
f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio
f2fs: Convert f2fs_set_meta_page_dirty to f2fs_dirty_meta_folio
afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio()
btrfs: Convert extent_range_redirty_for_io() to use folios
fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio
btrfs: Convert from set_page_dirty to dirty_folio
fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio()
fs: Add aops->dirty_folio
fs: Remove aops->launder_page
orangefs: Convert launder_page to launder_folio
nfs: Convert from launder_page to launder_folio
fuse: Convert from launder_page to launder_folio
...
A lot of the underlying infrastructure in btrfs needs to be switched
over to folios, but this at least documents that invalidatepage can't
be passed a tail page.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs
We don't need a root here, we just need the btrfs_fs_info, we can just
get the specific roots we need from fs_info.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When a filesystem goes read-only due to an error, multiple errors tend
to be reported, some of which are knock-on failures. Logging fs_states,
in btrfs_handle_fs_error() and btrfs_printk() helps distinguish the
first error from subsequent messages which may only exist due to an
error state.
Under the new format, most initial errors will look like:
`BTRFS: error (device loop0) in ...`
while subsequent errors will begin with:
`error (device loop0: state E) in ...`
An initial transaction abort error will look like
`error (device loop0: state A) in ...`
and subsequent messages will contain
`(device loop0: state EA) in ...`
In addition to the error states we can also print other states that are
temporary, like remounting, device replace, or indicate a global state
that may affect functionality.
Now implemented:
E - filesystem error detected
A - transaction aborted
L - log tree errors
M - remounting in progress
R - device replace in progress
C - data checksums not verified (mounted with ignoredatacsums)
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The implementation resembles direct I/O: we have to flush any ordered
extents, invalidate the page cache, and do the io tree/delalloc/extent
map/ordered extent dance. From there, we can reuse the compression code
with a minor modification to distinguish the write from writeback. This
also creates inline extents when possible.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are 4 main cases:
1. Inline extents: we copy the data straight out of the extent buffer.
2. Hole/preallocated extents: we fill in zeroes.
3. Regular, uncompressed extents: we read the sectors we need directly
from disk.
4. Regular, compressed extents: we read the entire compressed extent
from disk and indicate what subset of the decompressed extent is in
the file.
This initial implementation simplifies a few things that can be improved
in the future:
- Cases 1, 3, and 4 allocate temporary memory to read into before
copying out to userspace.
- We don't do read repair, because it turns out that read repair is
currently broken for compressed data.
- We hold the inode lock during the operation.
Note that we don't need to hold the mmap lock. We may race with
btrfs_page_mkwrite() and read the old data from before the page was
dirtied:
btrfs_page_mkwrite btrfs_encoded_read
---------------------------------------------------
(enter) (enter)
btrfs_wait_ordered_range
lock_extent_bits
btrfs_page_set_dirty
unlock_extent_cached
(exit)
lock_extent_bits
read extent (dirty page hasn't been flushed,
so this is the old data)
unlock_extent_cached
(exit)
we read the old data from before the page was dirtied. But, that's true
even if we were to hold the mmap lock:
btrfs_page_mkwrite btrfs_encoded_read
-------------------------------------------------------------------
(enter) (enter)
btrfs_inode_lock(BTRFS_ILOCK_MMAP)
down_read(i_mmap_lock) (blocked)
btrfs_wait_ordered_range
lock_extent_bits
read extent (page hasn't been dirtied,
so this is the old data)
unlock_extent_cached
btrfs_inode_unlock(BTRFS_ILOCK_MMAP)
down_read(i_mmap_lock) returns
lock_extent_bits
btrfs_page_set_dirty
unlock_extent_cached
In other words, this is inherently racy, so it's fine that we return the
old data in this tiny window.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently, we always reserve the same extent size in the file and extent
size on disk for delalloc because the former is the worst case for the
latter. For BTRFS_IOC_ENCODED_WRITE writes, we know the exact size of
the extent on disk, which may be less than or greater than (for
bookends) the size in the file. Add a disk_num_bytes parameter to
btrfs_delalloc_reserve_metadata() so that we can reserve the correct
amount of csum bytes. No functional change.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_csum_one_bio() loops over each filesystem block in the bio while
keeping a cursor of its current logical position in the file in order to
look up the ordered extent to add the checksums to. However, this
doesn't make much sense for compressed extents, as a sector on disk does
not correspond to a sector of decompressed file data. It happens to work
because:
1) the compressed bio always covers one ordered extent
2) the size of the bio is always less than the size of the ordered
extent
However, the second point will not always be true for encoded writes.
Let's add a boolean parameter to btrfs_csum_one_bio() to indicate that
it can assume that the bio only covers one ordered extent. Since we're
already changing the signature, let's get rid of the contig parameter
and make it implied by the offset parameter, similar to the change we
recently made to btrfs_lookup_bio_sums(). Additionally, let's rename
nr_sectors to blockcount to make it clear that it's the number of
filesystem blocks, not the number of 512-byte sectors.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The static_assert introduced in 6bab69c650 ("build_bug.h: add wrapper
for _Static_assert") has been supported by compilers for a long time
(gcc 4.6, clang 3.0) and can be used in header files. We don't need to
put BUILD_BUG_ON to random functions but rather keep it next to the
definition.
The exception here is the UAPI header btrfs_tree.h that could be
potentially included by userspace code and the static assert is not
defined (nor used in any other header).
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With extent tree v2 you will be able to create multiple csum, extent,
and free space trees. They will be used based on the block group, which
will now use the block_group_item->chunk_objectid to point to the set of
global roots that it will use. When allocating new block groups we'll
simply mod the gigabyte offset of the block group against the number of
global roots we have and that will be the block groups global id.
>From there we can take the bytenr that we're modifying in the respective
tree, look up the block group and get that block groups corresponding
global root id. From there we can get to the appropriate global root
for that bytenr.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This code adds the on disk structures for the block group root, which
will hold the block group items for extent tree v2.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds the initial definition of the EXTENT_TREE_V2 incompat feature
flag. This also hides the support behind CONFIG_BTRFS_DEBUG.
THIS IS A IN DEVELOPMENT FORMAT CHANGE, DO NOT USE UNLESS YOU ARE A
DEVELOPER OR A TESTER.
The format is in flux and will be added in stages, any fs will need to
be re-made between updates to the format.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We hit a bug with a recovering relocation on mount for one of our file
systems in production. I reproduced this locally by injecting errors
into snapshot delete with balance running at the same time. This
presented as an error while looking up an extent item
WARNING: CPU: 5 PID: 1501 at fs/btrfs/extent-tree.c:866 lookup_inline_extent_backref+0x647/0x680
CPU: 5 PID: 1501 Comm: btrfs-balance Not tainted 5.16.0-rc8+ #8
RIP: 0010:lookup_inline_extent_backref+0x647/0x680
RSP: 0018:ffffae0a023ab960 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000000
RBP: ffff943fd2a39b60 R08: 0000000000000000 R09: 0000000000000001
R10: 0001434088152de0 R11: 0000000000000000 R12: 0000000001d05000
R13: ffff943fd2a39b60 R14: ffff943fdb96f2a0 R15: ffff9442fc923000
FS: 0000000000000000(0000) GS:ffff944e9eb40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1157b1fca8 CR3: 000000010f092000 CR4: 0000000000350ee0
Call Trace:
<TASK>
insert_inline_extent_backref+0x46/0xd0
__btrfs_inc_extent_ref.isra.0+0x5f/0x200
? btrfs_merge_delayed_refs+0x164/0x190
__btrfs_run_delayed_refs+0x561/0xfa0
? btrfs_search_slot+0x7b4/0xb30
? btrfs_update_root+0x1a9/0x2c0
btrfs_run_delayed_refs+0x73/0x1f0
? btrfs_update_root+0x1a9/0x2c0
btrfs_commit_transaction+0x50/0xa50
? btrfs_update_reloc_root+0x122/0x220
prepare_to_merge+0x29f/0x320
relocate_block_group+0x2b8/0x550
btrfs_relocate_block_group+0x1a6/0x350
btrfs_relocate_chunk+0x27/0xe0
btrfs_balance+0x777/0xe60
balance_kthread+0x35/0x50
? btrfs_balance+0xe60/0xe60
kthread+0x16b/0x190
? set_kthread_struct+0x40/0x40
ret_from_fork+0x22/0x30
</TASK>
Normally snapshot deletion and relocation are excluded from running at
the same time by the fs_info->cleaner_mutex. However if we had a
pending balance waiting to get the ->cleaner_mutex, and a snapshot
deletion was running, and then the box crashed, we would come up in a
state where we have a half deleted snapshot.
Again, in the normal case the snapshot deletion needs to complete before
relocation can start, but in this case relocation could very well start
before the snapshot deletion completes, as we simply add the root to the
dead roots list and wait for the next time the cleaner runs to clean up
the snapshot.
Fix this by setting a bit on the fs_info if we have any DEAD_ROOT's that
had a pending drop_progress key. If they do then we know we were in the
middle of the drop operation and set a flag on the fs_info. Then
balance can wait until this flag is cleared to start up again.
If there are DEAD_ROOT's that don't have a drop_progress set then we're
safe to start balance right away as we'll be properly protected by the
cleaner_mutex.
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a big gap between inode_should_defrag() and autodefrag extent
size threshold. For inode_should_defrag() it has a flexible
@small_write value. For compressed extent is 16K, and for non-compressed
extent it's 64K.
However for autodefrag extent size threshold, it's always fixed to the
default value (256K).
This means, the following write sequence will trigger autodefrag to
defrag ranges which didn't trigger autodefrag:
pwrite 0 8k
sync
pwrite 8k 128K
sync
The latter 128K write will also be considered as a defrag target (if
other conditions are met). While only that 8K write is really
triggering autodefrag.
Such behavior can cause extra IO for autodefrag.
Close the gap, by copying the @small_write value into inode_defrag, so
that later autodefrag can use the same @small_write value which
triggered autodefrag.
With the existing transid value, this allows autodefrag really to scan
the ranges which triggered autodefrag.
Although this behavior change is mostly reducing the extent_thresh value
for autodefrag, I believe in the future we should allow users to specify
the autodefrag extent threshold through mount options, but that's an
other problem to consider in the future.
CC: stable@vger.kernel.org # 5.16+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
After the recent changes made by commit c2e3930529 ("btrfs: clear
extent buffer uptodate when we fail to write it") and its followup fix,
commit 651740a502 ("btrfs: check WRITE_ERR when trying to read an
extent buffer"), we can now end up not cleaning up space reservations of
log tree extent buffers after a transaction abort happens, as well as not
cleaning up still dirty extent buffers.
This happens because if writeback for a log tree extent buffer failed,
then we have cleared the bit EXTENT_BUFFER_UPTODATE from the extent buffer
and we have also set the bit EXTENT_BUFFER_WRITE_ERR on it. Later on,
when trying to free the log tree with free_log_tree(), which iterates
over the tree, we can end up getting an -EIO error when trying to read
a node or a leaf, since read_extent_buffer_pages() returns -EIO if an
extent buffer does not have EXTENT_BUFFER_UPTODATE set and has the
EXTENT_BUFFER_WRITE_ERR bit set. Getting that -EIO means that we return
immediately as we can not iterate over the entire tree.
In that case we never update the reserved space for an extent buffer in
the respective block group and space_info object.
When this happens we get the following traces when unmounting the fs:
[174957.284509] BTRFS: error (device dm-0) in cleanup_transaction:1913: errno=-5 IO failure
[174957.286497] BTRFS: error (device dm-0) in free_log_tree:3420: errno=-5 IO failure
[174957.399379] ------------[ cut here ]------------
[174957.402497] WARNING: CPU: 2 PID: 3206883 at fs/btrfs/block-group.c:127 btrfs_put_block_group+0x77/0xb0 [btrfs]
[174957.407523] Modules linked in: btrfs overlay dm_zero (...)
[174957.424917] CPU: 2 PID: 3206883 Comm: umount Tainted: G W 5.16.0-rc5-btrfs-next-109 #1
[174957.426689] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[174957.428716] RIP: 0010:btrfs_put_block_group+0x77/0xb0 [btrfs]
[174957.429717] Code: 21 48 8b bd (...)
[174957.432867] RSP: 0018:ffffb70d41cffdd0 EFLAGS: 00010206
[174957.433632] RAX: 0000000000000001 RBX: ffff8b09c3848000 RCX: ffff8b0758edd1c8
[174957.434689] RDX: 0000000000000001 RSI: ffffffffc0b467e7 RDI: ffff8b0758edd000
[174957.436068] RBP: ffff8b0758edd000 R08: 0000000000000000 R09: 0000000000000000
[174957.437114] R10: 0000000000000246 R11: 0000000000000000 R12: ffff8b09c3848148
[174957.438140] R13: ffff8b09c3848198 R14: ffff8b0758edd188 R15: dead000000000100
[174957.439317] FS: 00007f328fb82800(0000) GS:ffff8b0a2d200000(0000) knlGS:0000000000000000
[174957.440402] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[174957.441164] CR2: 00007fff13563e98 CR3: 0000000404f4e005 CR4: 0000000000370ee0
[174957.442117] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[174957.443076] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[174957.443948] Call Trace:
[174957.444264] <TASK>
[174957.444538] btrfs_free_block_groups+0x255/0x3c0 [btrfs]
[174957.445238] close_ctree+0x301/0x357 [btrfs]
[174957.445803] ? call_rcu+0x16c/0x290
[174957.446250] generic_shutdown_super+0x74/0x120
[174957.446832] kill_anon_super+0x14/0x30
[174957.447305] btrfs_kill_super+0x12/0x20 [btrfs]
[174957.447890] deactivate_locked_super+0x31/0xa0
[174957.448440] cleanup_mnt+0x147/0x1c0
[174957.448888] task_work_run+0x5c/0xa0
[174957.449336] exit_to_user_mode_prepare+0x1e5/0x1f0
[174957.449934] syscall_exit_to_user_mode+0x16/0x40
[174957.450512] do_syscall_64+0x48/0xc0
[174957.450980] entry_SYSCALL_64_after_hwframe+0x44/0xae
[174957.451605] RIP: 0033:0x7f328fdc4a97
[174957.452059] Code: 03 0c 00 f7 (...)
[174957.454320] RSP: 002b:00007fff13564ec8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[174957.455262] RAX: 0000000000000000 RBX: 00007f328feea264 RCX: 00007f328fdc4a97
[174957.456131] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000560b8ae51dd0
[174957.457118] RBP: 0000560b8ae51ba0 R08: 0000000000000000 R09: 00007fff13563c40
[174957.458005] R10: 00007f328fe49fc0 R11: 0000000000000246 R12: 0000000000000000
[174957.459113] R13: 0000560b8ae51dd0 R14: 0000560b8ae51cb0 R15: 0000000000000000
[174957.460193] </TASK>
[174957.460534] irq event stamp: 0
[174957.461003] hardirqs last enabled at (0): [<0000000000000000>] 0x0
[174957.461947] hardirqs last disabled at (0): [<ffffffffb0e94214>] copy_process+0x934/0x2040
[174957.463147] softirqs last enabled at (0): [<ffffffffb0e94214>] copy_process+0x934/0x2040
[174957.465116] softirqs last disabled at (0): [<0000000000000000>] 0x0
[174957.466323] ---[ end trace bc7ee0c490bce3af ]---
[174957.467282] ------------[ cut here ]------------
[174957.468184] WARNING: CPU: 2 PID: 3206883 at fs/btrfs/block-group.c:3976 btrfs_free_block_groups+0x330/0x3c0 [btrfs]
[174957.470066] Modules linked in: btrfs overlay dm_zero (...)
[174957.483137] CPU: 2 PID: 3206883 Comm: umount Tainted: G W 5.16.0-rc5-btrfs-next-109 #1
[174957.484691] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[174957.486853] RIP: 0010:btrfs_free_block_groups+0x330/0x3c0 [btrfs]
[174957.488050] Code: 00 00 00 ad de (...)
[174957.491479] RSP: 0018:ffffb70d41cffde0 EFLAGS: 00010206
[174957.492520] RAX: ffff8b08d79310b0 RBX: ffff8b09c3848000 RCX: 0000000000000000
[174957.493868] RDX: 0000000000000001 RSI: fffff443055ee600 RDI: ffffffffb1131846
[174957.495183] RBP: ffff8b08d79310b0 R08: 0000000000000000 R09: 0000000000000000
[174957.496580] R10: 0000000000000001 R11: 0000000000000000 R12: ffff8b08d7931000
[174957.498027] R13: ffff8b09c38492b0 R14: dead000000000122 R15: dead000000000100
[174957.499438] FS: 00007f328fb82800(0000) GS:ffff8b0a2d200000(0000) knlGS:0000000000000000
[174957.500990] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[174957.502117] CR2: 00007fff13563e98 CR3: 0000000404f4e005 CR4: 0000000000370ee0
[174957.503513] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[174957.504864] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[174957.506167] Call Trace:
[174957.506654] <TASK>
[174957.507047] close_ctree+0x301/0x357 [btrfs]
[174957.507867] ? call_rcu+0x16c/0x290
[174957.508567] generic_shutdown_super+0x74/0x120
[174957.509447] kill_anon_super+0x14/0x30
[174957.510194] btrfs_kill_super+0x12/0x20 [btrfs]
[174957.511123] deactivate_locked_super+0x31/0xa0
[174957.511976] cleanup_mnt+0x147/0x1c0
[174957.512610] task_work_run+0x5c/0xa0
[174957.513309] exit_to_user_mode_prepare+0x1e5/0x1f0
[174957.514231] syscall_exit_to_user_mode+0x16/0x40
[174957.515069] do_syscall_64+0x48/0xc0
[174957.515718] entry_SYSCALL_64_after_hwframe+0x44/0xae
[174957.516688] RIP: 0033:0x7f328fdc4a97
[174957.517413] Code: 03 0c 00 f7 d8 (...)
[174957.521052] RSP: 002b:00007fff13564ec8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[174957.522514] RAX: 0000000000000000 RBX: 00007f328feea264 RCX: 00007f328fdc4a97
[174957.523950] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000560b8ae51dd0
[174957.525375] RBP: 0000560b8ae51ba0 R08: 0000000000000000 R09: 00007fff13563c40
[174957.526763] R10: 00007f328fe49fc0 R11: 0000000000000246 R12: 0000000000000000
[174957.528058] R13: 0000560b8ae51dd0 R14: 0000560b8ae51cb0 R15: 0000000000000000
[174957.529404] </TASK>
[174957.529843] irq event stamp: 0
[174957.530256] hardirqs last enabled at (0): [<0000000000000000>] 0x0
[174957.531061] hardirqs last disabled at (0): [<ffffffffb0e94214>] copy_process+0x934/0x2040
[174957.532075] softirqs last enabled at (0): [<ffffffffb0e94214>] copy_process+0x934/0x2040
[174957.533083] softirqs last disabled at (0): [<0000000000000000>] 0x0
[174957.533865] ---[ end trace bc7ee0c490bce3b0 ]---
[174957.534452] BTRFS info (device dm-0): space_info 4 has 1070841856 free, is not full
[174957.535404] BTRFS info (device dm-0): space_info total=1073741824, used=2785280, pinned=0, reserved=49152, may_use=0, readonly=65536 zone_unusable=0
[174957.537029] BTRFS info (device dm-0): global_block_rsv: size 0 reserved 0
[174957.537859] BTRFS info (device dm-0): trans_block_rsv: size 0 reserved 0
[174957.538697] BTRFS info (device dm-0): chunk_block_rsv: size 0 reserved 0
[174957.539552] BTRFS info (device dm-0): delayed_block_rsv: size 0 reserved 0
[174957.540403] BTRFS info (device dm-0): delayed_refs_rsv: size 0 reserved 0
This also means that in case we have log tree extent buffers that are
still dirty, we can end up not cleaning them up in case we find an
extent buffer with EXTENT_BUFFER_WRITE_ERR set on it, as in that case
we have no way for iterating over the rest of the tree.
This issue is very often triggered with test cases generic/475 and
generic/648 from fstests.
The issue could almost be fixed by iterating over the io tree attached to
each log root which keeps tracks of the range of allocated extent buffers,
log_root->dirty_log_pages, however that does not work and has some
inconveniences:
1) After we sync the log, we clear the range of the extent buffers from
the io tree, so we can't find them after writeback. We could keep the
ranges in the io tree, with a separate bit to signal they represent
extent buffers already written, but that means we need to hold into
more memory until the transaction commits.
How much more memory is used depends a lot on whether we are able to
allocate contiguous extent buffers on disk (and how often) for a log
tree - if we are able to, then a single extent state record can
represent multiple extent buffers, otherwise we need multiple extent
state record structures to track each extent buffer.
In fact, my earlier approach did that:
https://lore.kernel.org/linux-btrfs/3aae7c6728257c7ce2279d6660ee2797e5e34bbd.1641300250.git.fdmanana@suse.com/
However that can cause a very significant negative impact on
performance, not only due to the extra memory usage but also because
we get a larger and deeper dirty_log_pages io tree.
We got a report that, on beefy machines at least, we can get such
performance drop with fsmark for example:
https://lore.kernel.org/linux-btrfs/20220117082426.GE32491@xsang-OptiPlex-9020/
2) We would be doing it only to deal with an unexpected and exceptional
case, which is basically failure to read an extent buffer from disk
due to IO failures. On a healthy system we don't expect transaction
aborts to happen after all;
3) Instead of relying on iterating the log tree or tracking the ranges
of extent buffers in the dirty_log_pages io tree, using the radix
tree that tracks extent buffers (fs_info->buffer_radix) to find all
log tree extent buffers is not reliable either, because after writeback
of an extent buffer it can be evicted from memory by the release page
callback of the btree inode (btree_releasepage()).
Since there's no way to be able to properly cleanup a log tree without
being able to read its extent buffers from disk and without using more
memory to track the logical ranges of the allocated extent buffers do
the following:
1) When we fail to cleanup a log tree, setup a flag that indicates that
failure;
2) Trigger writeback of all log tree extent buffers that are still dirty,
and wait for the writeback to complete. This is just to cleanup their
state, page states, page leaks, etc;
3) When unmounting the fs, ignore if the number of bytes reserved in a
block group and in a space_info is not 0 if, and only if, we failed to
cleanup a log tree. Also ignore only for metadata block groups and the
metadata space_info object.
This is far from a perfect solution, but it serves to silence test
failures such as those from generic/475 and generic/648. However having
a non-zero value for the reserved bytes counters on unmount after a
transaction abort, is not such a terrible thing and it's completely
harmless, it does not affect the filesystem integrity in any way.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently there is only one user for btrfs metadata readahead, and
that's scrub.
But even for the single user, it's not providing the correct
functionality it needs, as scrub needs reada for commit root, which
current readahead can't provide. (Although it's pretty easy to add such
feature).
Despite this, there are some extra problems related to metadata
readahead:
- Duplicated feature with btrfs_path::reada
- Partly duplicated feature of btrfs_fs_info::buffer_radix
Btrfs already caches its metadata in buffer_radix, while readahead
tries to read the tree block no matter if it's already cached.
- Poor layer separation
Metadata readahead works kinda at device level.
This is definitely not the correct layer it should be, since metadata
is at btrfs logical address space, it should not bother device at all.
This brings extra chance for bugs to sneak in, while brings
unnecessary complexity.
- Dead code
In the very beginning of scrub.c we have #undef DEBUG, rendering all
the debug related code useless and unable to test.
Thus here I purpose to remove the metadata readahead mechanism
completely.
[BENCHMARK]
There is a full benchmark for the scrub performance difference using the
old btrfs_reada_add() and btrfs_path::reada.
For the worst case (no dirty metadata, slow HDD), there could be a 5%
performance drop for scrub.
For other cases (even SATA SSD), there is no distinguishable performance
difference.
The number is reported scrub speed, in MiB/s.
The resolution is limited by the reported duration, which only has a
resolution of 1 second.
Old New Diff
SSD 455.3 466.332 +2.42%
HDD 103.927 98.012 -5.69%
Comprehensive test methodology is in the cover letter of the patch.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is an inode item related manipulation with a few vfs related
adjustments. I'm going to remove the vfs related code from this helper
and simplify it a lot, but I want those changes to be easily seen via
git blame, so move this function now and then the simplification work
can be done.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have a few helpers in inode-item.c, and I'm going to make a few
changes to how we do truncate in the future, so break out these
definitions into their own header file to trim down ctree.h some and
make it easier to do the work on truncate in the future.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Current set of exclusive operation states is not sufficient to handle
all practical use cases. In particular there is a need to be able to add
a device to a filesystem that have paused balance. Currently there is no
way to distinguish between a running and a paused balance. Fix this by
introducing BTRFS_EXCLOP_BALANCE_PAUSED which is going to be set in 2
occasions:
1. When a filesystem is mounted with skip_balance and there is an
unfinished balance it will now be into BALANCE_PAUSED instead of
simply BALANCE state.
2. When a running balance is paused.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We don't allow send and balance/relocation to run in parallel in order
to prevent send failing or silently producing some bad stream. This is
because while send is using an extent (specially metadata) or about to
read a metadata extent and expecting it belongs to a specific parent
node, relocation can run, the transaction used for the relocation is
committed and the extent gets reallocated while send is still using the
extent, so it ends up with a different content than expected. This can
result in just failing to read a metadata extent due to failure of the
validation checks (parent transid, level, etc), failure to find a
backreference for a data extent, and other unexpected failures. Besides
reallocation, there's also a similar problem of an extent getting
discarded when it's unpinned after the transaction used for block group
relocation is committed.
The restriction between balance and send was added in commit 9e967495e0
("Btrfs: prevent send failures and crashes due to concurrent relocation"),
kernel 5.3, while the more general restriction between send and relocation
was added in commit 1cea5cf0e6 ("btrfs: ensure relocation never runs
while we have send operations running"), kernel 5.14.
Both send and relocation can be very long running operations. Relocation
because it has to do a lot of IO and expensive backreference lookups in
case there are many snapshots, and send due to read IO when operating on
very large trees. This makes it inconvenient for users and tools to deal
with scheduling both operations.
For zoned filesystem we also have automatic block group relocation, so
send can fail with -EAGAIN when users least expect it or send can end up
delaying the block group relocation for too long. In the future we might
also get the automatic block group relocation for non zoned filesystems.
This change makes it possible for send and relocation to run in parallel.
This is achieved the following way:
1) For all tree searches, send acquires a read lock on the commit root
semaphore;
2) After each tree search, and before releasing the commit root semaphore,
the leaf is cloned and placed in the search path (struct btrfs_path);
3) After releasing the commit root semaphore, the changed_cb() callback
is invoked, which operates on the leaf and writes commands to the pipe
(or file in case send/receive is not used with a pipe). It's important
here to not hold a lock on the commit root semaphore, because if we did
we could deadlock when sending and receiving to the same filesystem
using a pipe - the send task blocks on the pipe because it's full, the
receive task, which is the only consumer of the pipe, triggers a
transaction commit when attempting to create a subvolume or reserve
space for a write operation for example, but the transaction commit
blocks trying to write lock the commit root semaphore, resulting in a
deadlock;
4) Before moving to the next key, or advancing to the next change in case
of an incremental send, check if a transaction used for relocation was
committed (or is about to finish its commit). If so, release the search
path(s) and restart the search, to where we were before, so that we
don't operate on stale extent buffers. The search restarts are always
possible because both the send and parent roots are RO, and no one can
add, remove of update keys (change their offset) in RO trees - the
only exception is deduplication, but that is still not allowed to run
in parallel with send;
5) Periodically check if there is contention on the commit root semaphore,
which means there is a transaction commit trying to write lock it, and
release the semaphore and reschedule if there is contention, so as to
avoid causing any significant delays to transaction commits.
This leaves some room for optimizations for send to have less path
releases and re searching the trees when there's relocation running, but
for now it's kept simple as it performs quite well (on very large trees
with resulting send streams in the order of a few hundred gigabytes).
Test case btrfs/187, from fstests, stresses relocation, send and
deduplication attempting to run in parallel, but without verifying if send
succeeds and if it produces correct streams. A new test case will be added
that exercises relocation happening in parallel with send and then checks
that send succeeds and the resulting streams are correct.
A final note is that for now this still leaves the mutual exclusion
between send operations and deduplication on files belonging to a root
used by send operations. A solution for that will be slightly more complex
but it will eventually be built on top of this change.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the future we are going to have multiple copies of these trees. To
facilitate this we need a way to lookup the different roots we are
looking for. Handle this by adding a global root rb tree that is
indexed on the root->root_key. Then instead of loading the roots at
mount time with individually targeted keys, simply search the tree_root
for anything with the specific objectid we want. This will make it
straightforward to support both old style and new style file systems.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're going to have multiple free space roots in the future, so adjust
all the users of the free space root to use a helper to access the root.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We are going to have multiple csum roots in the future, so convert all
users of ->csum_root to btrfs_csum_root() and rename ->csum_root to
->_csum_root so we can easily find remaining users in the future.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have a few places where we skip doing csums if we mounted with one of
the rescue options that ignores bad csum roots. In the future when
there are multiple csum roots it'll be costly to check and see if there
are any missing csum roots, so simply add a flag to indicate the fs
should skip loading csums in case of errors.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we start having multiple extent roots we'll need to use a helper to
get to the correct extent_root. Rename fs_info->extent_root to
_extent_root and convert all of the users of the extent root to using
the btrfs_extent_root() helper. This will allow us to easily clean up
the remaining direct accesses in the future.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we do this awful thing where we get another ref on a trans
handle, async off that handle and commit the transaction from that work.
Because we do this we have to mess with current->journal_info and the
freeze counting stuff.
We already have an async thing to kick for the transaction commit, the
transaction kthread. Replace this work struct with a flag on the
fs_info to tell the kthread to go ahead and commit even if it's before
our timeout. Then we can drastically simplify the async transaction
commit path.
Note: this can be simplified and functionality based on the pending
operation COMMIT.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
[ add note ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is no longer used, the -o nobarrier is handled by
BTRFS_MOUNT_NOBARRIER. Remove the flag.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we don't care about the stage of the orphan_cleanup_state,
simply replace it with a bit on ->state to make sure we don't call the
orphan cleanup every time we wander into this root.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The name btrfs_item_end_nr() is a bit of a misnomer, as it's actually
the offset of the end of the data the item points to. In fact all of
the helpers that we use btrfs_item_end_nr() use data in their name, like
BTRFS_LEAF_DATA_SIZE() and leaf_data(). Rename to btrfs_item_data_end()
to make it clear what this helper is giving us.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're only using btrfs_item_end() from btrfs_item_end_nr(), so this can
be collapsed.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that all call sites are using the slot number to modify item values,
rename the SETGET helpers to raw_item_*(), and then rework the _nr()
helpers to be the btrfs_item_*() btrfs_set_item_*() helpers, and then
rename all of the callers to the new helpers.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The last remaining place where we have the pattern of
item = btrfs_item_nr(slot)
<do something with the item>
are the token helpers. Handle this by introducing token helpers that
will do the btrfs_item_nr() work inside of the helper itself, and then
convert all users of the btrfs_item token helpers to the new _nr()
variants.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of getting the btrfs_item for this, simply pass in the slot of
the item and then use the btrfs_item_size_nr() helper inside of
btrfs_file_extent_inline_item_len().
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have the pattern of
item = btrfs_item_nr(slot);
btrfs_set_item_*(leaf, item);
in a bunch of places in our code. Fix this by adding
btrfs_set_item_*_nr() helpers which will do the appropriate work, and
replace those calls with
btrfs_set_item_*_nr(leaf, slot);
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When creating a subvolume, at ioctl.c:create_subvol(), if we fail to
insert the new root's root item into the root tree, we are freeing the
metadata extent we reserved for the new root to prevent a metadata
extent leak, as we don't abort the transaction at that point (since
there is nothing at that point that is irreversible).
However we allocated the metadata extent for the new root which we are
creating for the new subvolume, so its delayed reference refers to the
ID of this new root. But when we free the metadata extent we pass the
root of the subvolume where the new subvolume is located to
btrfs_free_tree_block() - this is incorrect because this will generate
a delayed reference that refers to the ID of the parent subvolume's root,
and not to ID of the new root.
This results in a failure when running delayed references that leads to
a transaction abort and a trace like the following:
[3868.738042] RIP: 0010:__btrfs_free_extent+0x709/0x950 [btrfs]
[3868.739857] Code: 68 0f 85 e6 fb ff (...)
[3868.742963] RSP: 0018:ffffb0e9045cf910 EFLAGS: 00010246
[3868.743908] RAX: 00000000fffffffe RBX: 00000000fffffffe RCX: 0000000000000002
[3868.745312] RDX: 00000000fffffffe RSI: 0000000000000002 RDI: ffff90b0cd793b88
[3868.746643] RBP: 000000000e5d8000 R08: 0000000000000000 R09: ffff90b0cd793b88
[3868.747979] R10: 0000000000000002 R11: 00014ded97944d68 R12: 0000000000000000
[3868.749373] R13: ffff90b09afe4a28 R14: 0000000000000000 R15: ffff90b0cd793b88
[3868.750725] FS: 00007f281c4a8b80(0000) GS:ffff90b3ada00000(0000) knlGS:0000000000000000
[3868.752275] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[3868.753515] CR2: 00007f281c6a5000 CR3: 0000000108a42006 CR4: 0000000000370ee0
[3868.754869] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[3868.756228] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[3868.757803] Call Trace:
[3868.758281] <TASK>
[3868.758655] ? btrfs_merge_delayed_refs+0x178/0x1c0 [btrfs]
[3868.759827] __btrfs_run_delayed_refs+0x2b1/0x1250 [btrfs]
[3868.761047] btrfs_run_delayed_refs+0x86/0x210 [btrfs]
[3868.762069] ? lock_acquired+0x19f/0x420
[3868.762829] btrfs_commit_transaction+0x69/0xb20 [btrfs]
[3868.763860] ? _raw_spin_unlock+0x29/0x40
[3868.764614] ? btrfs_block_rsv_release+0x1c2/0x1e0 [btrfs]
[3868.765870] create_subvol+0x1d8/0x9a0 [btrfs]
[3868.766766] btrfs_mksubvol+0x447/0x4c0 [btrfs]
[3868.767669] ? preempt_count_add+0x49/0xa0
[3868.768444] __btrfs_ioctl_snap_create+0x123/0x190 [btrfs]
[3868.769639] ? _copy_from_user+0x66/0xa0
[3868.770391] btrfs_ioctl_snap_create_v2+0xbb/0x140 [btrfs]
[3868.771495] btrfs_ioctl+0xd1e/0x35c0 [btrfs]
[3868.772364] ? __slab_free+0x10a/0x360
[3868.773198] ? rcu_read_lock_sched_held+0x12/0x60
[3868.774121] ? lock_release+0x223/0x4a0
[3868.774863] ? lock_acquired+0x19f/0x420
[3868.775634] ? rcu_read_lock_sched_held+0x12/0x60
[3868.776530] ? trace_hardirqs_on+0x1b/0xe0
[3868.777373] ? _raw_spin_unlock_irqrestore+0x3e/0x60
[3868.778280] ? kmem_cache_free+0x321/0x3c0
[3868.779011] ? __x64_sys_ioctl+0x83/0xb0
[3868.779718] __x64_sys_ioctl+0x83/0xb0
[3868.780387] do_syscall_64+0x3b/0xc0
[3868.781059] entry_SYSCALL_64_after_hwframe+0x44/0xae
[3868.781953] RIP: 0033:0x7f281c59e957
[3868.782585] Code: 3c 1c 48 f7 d8 4c (...)
[3868.785867] RSP: 002b:00007ffe1f83e2b8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[3868.787198] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f281c59e957
[3868.788450] RDX: 00007ffe1f83e2c0 RSI: 0000000050009418 RDI: 0000000000000003
[3868.789748] RBP: 00007ffe1f83f300 R08: 0000000000000000 R09: 00007ffe1f83fe36
[3868.791214] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
[3868.792468] R13: 0000000000000003 R14: 00007ffe1f83e2c0 R15: 00000000000003cc
[3868.793765] </TASK>
[3868.794037] irq event stamp: 0
[3868.794548] hardirqs last enabled at (0): [<0000000000000000>] 0x0
[3868.795670] hardirqs last disabled at (0): [<ffffffff98294214>] copy_process+0x934/0x2040
[3868.797086] softirqs last enabled at (0): [<ffffffff98294214>] copy_process+0x934/0x2040
[3868.798309] softirqs last disabled at (0): [<0000000000000000>] 0x0
[3868.799284] ---[ end trace be24c7002fe27747 ]---
[3868.799928] BTRFS info (device dm-0): leaf 241188864 gen 1268 total ptrs 214 free space 469 owner 2
[3868.801133] BTRFS info (device dm-0): refs 2 lock_owner 225627 current 225627
[3868.802056] item 0 key (237436928 169 0) itemoff 16250 itemsize 33
[3868.802863] extent refs 1 gen 1265 flags 2
[3868.803447] ref#0: tree block backref root 1610
(...)
[3869.064354] item 114 key (241008640 169 0) itemoff 12488 itemsize 33
[3869.065421] extent refs 1 gen 1268 flags 2
[3869.066115] ref#0: tree block backref root 1689
(...)
[3869.403834] BTRFS error (device dm-0): unable to find ref byte nr 241008640 parent 0 root 1622 owner 0 offset 0
[3869.405641] BTRFS: error (device dm-0) in __btrfs_free_extent:3076: errno=-2 No such entry
[3869.407138] BTRFS: error (device dm-0) in btrfs_run_delayed_refs:2159: errno=-2 No such entry
Fix this by passing the new subvolume's root ID to btrfs_free_tree_block().
This requires changing the root argument of btrfs_free_tree_block() from
struct btrfs_root * to a u64, since at this point during the subvolume
creation we have not yet created the struct btrfs_root for the new
subvolume, and btrfs_free_tree_block() only needs a root ID and nothing
else from a struct btrfs_root.
This was triggered by test case generic/475 from fstests.
Fixes: 67addf2900 ("btrfs: fix metadata extent leak after failure to create subvolume")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The root argument passed to btrfs_unlink_inode() and its callee,
__btrfs_unlink_inode(), always matches the root of the given directory and
the given inode. So remove the argument and make __btrfs_unlink_inode()
use the root of the directory.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's a common practice to avoid use sizeof(struct btrfs_super_block)
(3531), but to use BTRFS_SUPER_INFO_SIZE (4096).
The problem is that, sizeof(struct btrfs_super_block) doesn't match
BTRFS_SUPER_INFO_SIZE from the very beginning.
Furthermore, for all call sites except selftests, we always allocate
BTRFS_SUPER_INFO_SIZE space for super block, there isn't any real reason
to use the smaller value, and it doesn't really save any space.
So let's get rid of such confusing behavior, and unify those two values.
This modification also adds a new static_assert() to verify the size,
and moves the BTRFS_SUPER_INFO_* macros to the definition of
btrfs_super_block for the static_assert().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have a few flags that are inconsistently used to describe the fs in
different states of failure. As of 5963ffcaf3 ("btrfs: always abort
the transaction if we abort a trans handle") we will always set
BTRFS_FS_STATE_ERROR if we abort, so we don't have to check both ABORTED
and ERROR to see if things have gone wrong. Add a helper to check
BTRFS_FS_STATE_ERROR and then convert all checkers of FS_STATE_ERROR to
use the helper.
The TRANS_ABORTED bit check was added in af72273381 ("Btrfs: clean up
resources during umount after trans is aborted") but is not actually
specific.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As the last caller in compression.c has been removed, we don't need that
function anymore.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since setup_items_for_insert() is not used anymore outside of ctree.c,
make it static and remove its prototype from ctree.h. This also requires
to move the definition of setup_item_for_insert() from ctree.h to ctree.c
and move down btrfs_duplicate_item() so that it's defined after
setup_items_for_insert().
Further, since setup_item_for_insert() is used outside ctree.c, rename it
to btrfs_setup_item_for_insert().
This patch is part of a small patchset that is comprised of the following
patches:
btrfs: loop only once over data sizes array when inserting an item batch
btrfs: unexport setup_items_for_insert()
btrfs: use single bulk copy operations when logging directories
This is patch 2/3 and performance results, and the specific tests, are
included in the changelog of patch 3/3.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When inserting a batch of items into a btree, we end up looping over the
data sizes array 3 times:
1) Once in the caller of btrfs_insert_empty_items(), when it populates the
array with the data sizes for each item;
2) Once at btrfs_insert_empty_items() to sum the elements of the data
sizes array and compute the total data size;
3) And then once again at setup_items_for_insert(), where we do exactly
the same as what we do at btrfs_insert_empty_items(), to compute the
total data size.
That is not bad for small arrays, but when the arrays have hundreds of
elements, the time spent on looping is not negligible. For example when
doing batch inserts of delayed items for dir index items or when logging
a directory, it's common to have 200 to 260 dir index items in a single
batch when using a leaf size of 16K and using file names between 8 and 12
characters. For a 64K leaf size, multiply that by 4. Taking into account
that during directory logging or when flushing delayed dir index items we
can have many of those large batches, the time spent on the looping adds
up quickly.
It's also more important to avoid it at setup_items_for_insert(), since
we are holding a write lock on a leaf and, in some cases, on upper nodes
of the btree, which causes us to block other tasks that want to access
the leaf and nodes for longer than necessary.
So change the code so that setup_items_for_insert() and
btrfs_insert_empty_items() no longer compute the total data size, and
instead rely on the caller to supply it. This makes us loop over the
array only once, where we can both populate the data size array and
compute the total data size, taking advantage of spatial and temporal
locality. To make this more manageable, use a structure to contain
all the relevant details for a batch of items (keys array, data sizes
array, total data size, number of items), and use it as an argument
for btrfs_insert_empty_items() and setup_items_for_insert().
This patch is part of a small patchset that is comprised of the following
patches:
btrfs: loop only once over data sizes array when inserting an item batch
btrfs: unexport setup_items_for_insert()
btrfs: use single bulk copy operations when logging directories
This is patch 1/3 and performance results, and the specific tests, are
included in the changelog of patch 3/3.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Previously we had "struct btrfs_bio", which records IO context for
mirrored IO and RAID56, and "strcut btrfs_io_bio", which records extra
btrfs specific info for logical bytenr bio.
With "btrfs_bio" renamed to "btrfs_io_context", we are safe to rename
"btrfs_io_bio" to "btrfs_bio" which is a more suitable name now.
The struct btrfs_bio changes meaning by this commit. There was a
suggested name like btrfs_logical_bio but it's a bit long and we'd
prefer to use a shorter name.
This could be a concern for backports to older kernels where the
different meaning could possibly cause confusion or bugs. Comparing the
new and old structures, there's no overlap among the struct members so a
build would break in case of incorrect backport.
We haven't had many backports to bio code anyway so this is more of a
theoretical cause of bugs and a matter of precaution but we'll need to
keep the semantic change in mind.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Relocation in a zoned filesystem can fail with a transaction abort with
error -22 (EINVAL). This happens because the relocation code assumes that
the extents we relocated the data to have the same size the source extents
had and ensures this by preallocating the extents.
But in a zoned filesystem we currently can't preallocate the extents as
this would break the sequential write required rule. Therefore it can
happen that the writeback process kicks in while we're still adding pages
to a delalloc range and starts writing out dirty pages.
This then creates destination extents that are smaller than the source
extents, triggering the following safety check in get_new_location():
1034 if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) {
1035 ret = -EINVAL;
1036 goto out;
1037 }
Temporarily create a dedicated block group for the relocation process, so
no non-relocation data writes can interfere with the relocation writes.
This is needed that we can switch the relocation process on a zoned
filesystem from the REQ_OP_ZONE_APPEND writing we use for data to a scheme
like in a non-zoned filesystem using REQ_OP_WRITE and preallocation.
Fixes: 32430c6148 ("btrfs: zoned: enable relocation on a zoned filesystem")
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are several places in our codebase where we check if a root is the
root of the data reloc tree and subsequent patches will introduce more.
Factor out the check into a small helper function instead of open coding
it multiple times.
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add zone_is_active flag to btrfs_block_group. This flag indicates the
underlying zones are all active. Such zone active block groups are tracked
by fs_info->active_bg_list.
btrfs_dev_{set,clear}_active_zone() take responsibility for the underlying
device part. They set/clear the bitmap to indicate zone activeness and
count the number of zones we can activate left.
btrfs_zone_{activate,finish}() take responsibility for the logical part and
the list management. In addition, btrfs_zone_finish() wait for any writes
on it and send REQ_OP_ZONE_FINISH to the zone.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs_defrag_file() accepts both "struct inode" and "struct
file" as parameter. We can easily grab "struct inode" from "struct
file" using file_inode() helper.
The reason why we need "struct file" is just to re-use its f_ra.
Change this to pass "struct file_ra_state" parameter, so that it's more
clear what we really want. Since we're here, also add some comments on
the function btrfs_defrag_file().
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we use fixed size u16 bitmap for subpage bitmap. This is fine
for 4K sectorsize with 64K page size.
But for 4K sectorsize and larger page size, the bitmap is too small,
while for smaller page size like 16K, u16 bitmaps waste too much space.
Here we introduce a new helper structure, btrfs_subpage_bitmap_info, to
record the proper bitmap size, and where each bitmap should start at.
By this, we can later compact all subpage bitmaps into one u32 bitmap.
This patch is the first step.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-5.15-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A few more error handling fixes, stemming from code inspection, error
injection or fuzzing"
* tag 'for-5.15-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix abort logic in btrfs_replace_file_extents
btrfs: check for error when looking up inode during dir entry replay
btrfs: unify lookup return value when dir entry is missing
btrfs: deal with errors when adding inode reference during log replay
btrfs: deal with errors when replaying dir entry during log replay
btrfs: deal with errors when checking if a dir entry exists during log replay
btrfs: update refs for any root except tree log roots
btrfs: unlock newly allocated extent buffer after error
btrfs_lookup_dir_index_item() and btrfs_lookup_dir_item() lookup for dir
entries and both are used during log replay or when updating a log tree
during an unlink.
However when the dir item does not exists, btrfs_lookup_dir_item() returns
NULL while btrfs_lookup_dir_index_item() returns PTR_ERR(-ENOENT), and if
the dir item exists but there is no matching entry for a given name or
index, both return NULL. This makes the call sites during log replay to
be more verbose than necessary and it makes it easy to miss this slight
difference. Since we don't need to distinguish between those two cases,
make btrfs_lookup_dir_index_item() always return NULL when there is no
matching directory entry - either because there isn't any dir entry or
because there is one but it does not match the given name and index.
Also rename the argument 'objectid' of btrfs_lookup_dir_index_item() to
'index' since it is supposed to match an index number, and the name
'objectid' is not very good because it can easily be confused with an
inode number (like the inode number a dir entry points to).
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs update from Miklos Szeredi:
- Copy up immutable/append/sync/noatime attributes (Amir Goldstein)
- Improve performance by enabling RCU lookup.
- Misc fixes and improvements
The reason this touches so many files is that the ->get_acl() method now
gets a "bool rcu" argument. The ->get_acl() API was updated based on
comments from Al and Linus:
Link: https://lore.kernel.org/linux-fsdevel/CAJfpeguQxpd6Wgc0Jd3ks77zcsAv_bn0q17L3VNnnmPKu11t8A@mail.gmail.com/
* tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: enable RCU'd ->get_acl()
vfs: add rcu argument to ->get_acl() callback
ovl: fix BUG_ON() in may_delete() when called from ovl_cleanup()
ovl: use kvalloc in xattr copy-up
ovl: update ctime when changing fileattr
ovl: skip checking lower file's i_writecount on truncate
ovl: relax lookup error on mismatch origin ftype
ovl: do not set overlay.opaque for new directories
ovl: add ovl_allow_offline_changes() helper
ovl: disable decoding null uuid with redirect_dir
ovl: consistent behavior for immutable/append-only inodes
ovl: copy up sync/noatime fileattr flags
ovl: pass ovl_fs to ovl_check_setxattr()
fs: add generic helper for filling statx attribute flags
Creating subvolumes and snapshots is one of the core features of btrfs
and is even available to unprivileged users. Make it possible to use
subvolume and snapshot creation on idmapped mounts. This is a fairly
straightforward operation since all the permission checking helpers are
already capable of handling idmapped mounts. So we just need to pass
down the mount's userns.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's a common practice to start a search using offset (u64)-1, which is
the u64 maximum value, meaning that we want the search_slot function to
be set in the last item with the same objectid and type.
Once we are in this position, it's a matter to start a search backwards
by calling btrfs_previous_item, which will check if we'll need to go to
a previous leaf and other necessary checks, only to be sure that we are
in last offset of the same object and type.
The new btrfs_search_backwards function does the all these steps when
necessary, and can be used to avoid code duplication.
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add support for fsverity in btrfs. To support the generic interface in
fs/verity, we add two new item types in the fs tree for inodes with
verity enabled. One stores the per-file verity descriptor and btrfs
verity item and the other stores the Merkle tree data itself.
Verity checking is done in end_page_read just before a page is marked
uptodate. This naturally handles a variety of edge cases like holes,
preallocated extents, and inline extents. Some care needs to be taken to
not try to verity pages past the end of the file, which are accessed by
the generic buffered file reading code under some circumstances like
reading to the end of the last page and trying to read again. Direct IO
on a verity file falls back to buffered reads.
Verity relies on PageChecked for the Merkle tree data itself to avoid
re-walking up shared paths in the tree. For this reason, we need to
cache the Merkle tree data. Since the file is immutable after verity is
turned on, we can cache it at an index past EOF.
Use the new inode ro_flags to store verity on the inode item, so that we
can enable verity on a file, then rollback to an older kernel and still
mount the file system and read the file. Since we can't safely write the
file anymore without ruining the invariants of the Merkle tree, we mark
a ro_compat flag on the file system when a file has verity enabled.
Acked-by: Eric Biggers <ebiggers@google.com>
Co-developed-by: Chris Mason <clm@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently, inode flags are fully backwards incompatible in btrfs. If we
introduce a new inode flag, then tree-checker will detect it and fail.
This can even cause us to fail to mount entirely. To make it possible to
introduce new flags which can be read-only compatible, like VERITY, we
add new ro flags to btrfs without treating them quite so harshly in
tree-checker. A read-only file system can survive an unexpected flag,
and can be mounted.
As for the implementation, it unfortunately gets a little complicated.
The on-disk representation of the inode, btrfs_inode_item, has an __le64
for flags but the in-memory representation, btrfs_inode, uses a u32.
David Sterba had the nice idea that we could reclaim those wasted 32 bits
on disk and use them for the new ro_compat flags.
It turns out that the tree-checker code which checks for unknown flags
is broken, and ignores the upper 32 bits we are hoping to use. The issue
is that the flags use the literal 1 rather than 1ULL, so the flags are
signed ints, and one of them is specifically (1 << 31). As a result, the
mask which ORs the flags is a negative integer on machines where int is
32 bit twos complement. When tree-checker evaluates the expression:
btrfs_inode_flags(leaf, iitem) & ~BTRFS_INODE_FLAG_MASK)
The mask is something like 0x80000abc, which gets promoted to u64 with
sign extension to 0xffffffff80000abc. Negating that 64 bit mask leaves
all the upper bits zeroed, and we can't detect unexpected flags.
This suggests that we can't use those bits after all. Luckily, we have
good reason to believe that they are zero anyway. Inode flags are
metadata, which is always checksummed, so any bit flips that would
introduce 1s would cause a checksum failure anyway (excluding the
improbable case of the checksum getting corrupted exactly badly).
Further, unless the 1 << 31 flag is used, the cast to u64 of the 32 bit
inode flag should preserve its value and not add leading zeroes
(at least for twos complement). The only place that flag
(BTRFS_INODE_ROOT_ITEM_INIT) is used is in a special inode embedded in
the root item, and indeed for that inode we see 0xffffffff80000000 as
the flags on disk. However, that inode is never seen by tree checker,
nor is it used in a context where verity might be meaningful.
Theoretically, a future ro flag might cause trouble on that inode, so we
should proactively clean up that mess before it does.
With the introduction of the new ro flags, keep two separate unsigned
masks and check them against the appropriate u32. Since we no longer run
afoul of sign extension, this also stops writing out 0xffffffff80000000
in root_item inodes going forward.
Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have been hitting some early ENOSPC issues in production with more
recent kernels, and I tracked it down to us simply not flushing delalloc
as aggressively as we should be. With tracing I was seeing us failing
all tickets with all of the block rsvs at or around 0, with very little
pinned space, but still around 120MiB of outstanding bytes_may_used.
Upon further investigation I saw that we were flushing around 14 pages
per shrink call for delalloc, despite having around 2GiB of delalloc
outstanding.
Consider the example of a 8 way machine, all CPUs trying to create a
file in parallel, which at the time of this commit requires 5 items to
do. Assuming a 16k leaf size, we have 10MiB of total metadata reclaim
size waiting on reservations. Now assume we have 128MiB of delalloc
outstanding. With our current math we would set items to 20, and then
set to_reclaim to 20 * 256k, or 5MiB.
Assuming that we went through this loop all 3 times, for both
FLUSH_DELALLOC and FLUSH_DELALLOC_WAIT, and then did the full loop
twice, we'd only flush 60MiB of the 128MiB delalloc space. This could
leave a fair bit of delalloc reservations still hanging around by the
time we go to ENOSPC out all the remaining tickets.
Fix this two ways. First, change the calculations to be a fraction of
the total delalloc bytes on the system. Prior to this change we were
calculating based on dirty inodes so our math made more sense, now it's
just completely unrelated to what we're actually doing.
Second add a FLUSH_DELALLOC_FULL state, that we hold off until we've
gone through the flush states at least once. This will empty the system
of all delalloc so we're sure to be truly out of space when we start
failing tickets.
I'm tagging stable 5.10 and forward, because this is where we started
using the page stuff heavily again. This affects earlier kernel
versions as well, but would be a pain to backport to them as the
flushing mechanisms aren't the same.
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_next_leaf is a simple wrapper for btrfs_next_old_leaf so move it
to header to avoid the function call overhead.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since commit d75855b451 ("btrfs: Remove
extent_io_ops::writepage_start_hook") removes the writepage_start_hook()
and adds btrfs_writepage_cow_fixup() function, there is no need to
follow the old hook parameters.
Remove the @start and @end hook, since currently the fixup check is full
page check, it doesn't need @start and @end hook.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There used to be a patch in the original series for zoned support which
limited the extent size to max_zone_append_size, but this patch has been
dropped somewhere around v9.
We've decided to go the opposite direction, instead of limiting extents
in the first place we split them before submission to comply with the
device's limits.
Remove the related code, btrfs_fs_info::max_zone_append_size and
btrfs_zoned_device_info::max_zone_append_size.
This also removes the workaround for dm-crypt introduced in
1d68128c10 ("btrfs: zoned: fail mount if the device does not support
zone append") because the fix has been merged as f34ee1dce6 ("dm
crypt: Fix zoned block device support").
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add a rcu argument to the ->get_acl() callback to allow
get_cached_acl_rcu() to call the ->get_acl() method in the next patch.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This got added 14 years ago in 324ae4df00 ("Btrfs: Add block group
pinned accounting back") but it was not ever used. Subsequently its
usage got gradually removed in 8790d502e4 ("Btrfs: Add support for
mirroring across drives") and 11833d66be ("Btrfs: improve async block
group caching"). Let's remove it for good!
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
may_commit_transaction was introduced before the ticketing
infrastructure existed. There was a problem where we'd legitimately be
out of space, but every reservation would trigger a transaction commit
and then fail. Thus if you had 1000 things trying to make a
reservation, they'd all do the flushing loop and thus commit the
transaction 1000 times before they'd get their ENOSPC.
This helper was introduced to short circuit this, if there wasn't space
that could be reclaimed by committing the transaction then simply ENOSPC
out. This made true ENOSPC tests much faster as we didn't waste a bunch
of time.
However many of our bugs over the years have been from cases where we
didn't account for some space that would be reclaimed by committing a
transaction. The delayed refs rsv space, delayed rsv, many pinned bytes
miscalculations, etc. And in the meantime the original problem has been
solved with ticketing. We no longer will commit the transaction 1000
times. Instead we'll get 1000 waiters, we will go through the flushing
mechanisms, and if there's no progress after 2 loops we ENOSPC everybody
out. The ticketing infrastructure gives us a deterministic way to see
if we're making progress or not, thus we avoid a lot of extra work.
So simplify this step by simply unconditionally committing the
transaction. This removes what is arguably our most common source of
early ENOSPC bugs and will allow us to drastically simplify many of the
things we track because we simply won't need them with this stuff gone.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Relocation and send do not play well together because while send is
running a block group can be relocated, a transaction committed and
the respective disk extents get re-allocated and written to or discarded
while send is about to do something with the extents.
This was explained in commit 9e967495e0 ("Btrfs: prevent send failures
and crashes due to concurrent relocation"), which prevented balance and
send from running in parallel but it did not address one remaining case
where chunk relocation can happen: shrinking a device (and device deletion
which shrinks a device's size to 0 before deleting the device).
We also have now one more case where relocation is triggered: on zoned
filesystems partially used block groups get relocated by a background
thread, introduced in commit 18bb8bbf13 ("btrfs: zoned: automatically
reclaim zones").
So make sure that instead of preventing balance from running when there
are ongoing send operations, we prevent relocation from happening.
This uses the infrastructure recently added by a patch that has the
subject: "btrfs: add cancellable chunk relocation support".
Also it adds a spinlock used exclusively for the exclusivity between
send and relocation, as before fs_info->balance_mutex was used, which
would make an attempt to run send to block waiting for balance to
finish, which can take a lot of time on large filesystems.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Subjectively, CHECK_INTEGRITY_INCLUDING_EXTENT_DATA is quite long and
calling it CHECK_INTEGRITY_DATA still keeps the meaning and matches the
mount option name.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Switch defines of BTRFS_MOUNT_* to an enum (the symbolic names are
recorded in the debugging information for convenience).
There are two more things done but separating them would not make much
sense as it's touching the same lines:
- Renumber shifts 18..31 to 17..30 to get rid of the hole in the
sequence.
- Use 1UL as the value that gets shifted because we're approaching the
32bit limit and due to integer promotions the value of (1 << 31)
becomes 0xffffffff80000000 when cast to unsigned long (eg. the option
manipulating helpers).
This is not causing any problems yet as the operations are in-memory
and masking the 31st bit works, we don't have more than 31 bits so the
ill effects of not masking higher bits don't happen. But once we have
more, the problems will emerge.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Function btrfs_set_range_writeback() currently just sets the page
writeback unconditionally.
Change it to call the subpage helper so that we can handle both cases
well.
Since the subpage helpers needs btrfs_fs_info, also change the parameter
to accept btrfs_inode.
Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64]
Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Inside btrfs we use Private2 page status to indicate we have an ordered
extent with pending IO for the sector.
But the page status name, Private2, tells us nothing about the bit
itself, so this patch will rename it to Ordered.
And with extra comment about the bit added, so reader who is still
uncertain about the page Ordered status, will find the comment pretty
easily.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a pretty bad abuse of btrfs_writepage_endio_finish_ordered() in
end_compressed_bio_write().
It passes compressed pages to btrfs_writepage_endio_finish_ordered(),
which is only supposed to accept inode pages.
Thankfully the important info here is the inode, so let's pass
btrfs_inode directly into btrfs_writepage_endio_finish_ordered(), and
make @page parameter optional.
By this, end_compressed_bio_write() can happily pass page=NULL while
still getting everything done properly.
Also, to cooperate with such modification, replace @page parameter for
trace_btrfs_writepage_end_io_hook() with btrfs_inode.
Although this removes page_index info, the existing start/len should be
enough for most usage.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a lot of code inside extent_io.c needs both "struct bio
**bio_ret" and "unsigned long prev_bio_flags", along with some
parameters like "unsigned long bio_flags".
Such strange parameters are here for bio assembly.
For example, we have such inode page layout:
0 4K 8K 12K
|<-- Extent A-->|<- EB->|
Then what we do is:
- Page [0, 4K)
*bio_ret = NULL
So we allocate a new bio to bio_ret,
Add page [0, 4K) to *bio_ret.
- Page [4K, 8K)
*bio_ret != NULL
We found this page is continuous to *bio_ret,
and if we're not at stripe boundary, we
add page [4K, 8K) to *bio_ret.
- Page [8K, 12K)
*bio_ret != NULL
But we found this page is not continuous, so
we submit *bio_ret, then allocate a new bio,
and add page [8K, 12K) to the new bio.
This means we need to record both the bio and its bio_flag, but we
record them manually using those strange parameter list, other than
encapsulating them into their own structure.
So this patch will introduce a new structure, btrfs_bio_ctrl, to record
both the bio, and its bio_flags.
Also, in above case, for all pages added to the bio, we need to check if
the new page crosses stripe boundary. This check itself can be time
consuming, and we don't really need to do that for each page.
This patch also integrates the stripe boundary check into btrfs_bio_ctrl.
When a new bio is allocated, the stripe and ordered extent boundary is
also calculated, so no matter how large the bio will be, we only
calculate the boundaries once, to save some CPU time.
The following functions/structures are affected:
- struct extent_page_data
Replace its bio pointer with structure btrfs_bio_ctrl (embedded
structure, not pointer)
- end_write_bio()
- flush_write_bio()
Just change how bio is fetched
- btrfs_bio_add_page()
Use pre-calculated boundaries instead of re-calculating them.
And use @bio_ctrl to replace @bio and @prev_bio_flags.
- calc_bio_boundaries()
New function
- submit_extent_page() callers
- btrfs_do_readpage() callers
- contiguous_readpages() callers
To Use @bio_ctrl to replace @bio and @prev_bio_flags, and how to grab
bio.
- btrfs_bio_fits_in_ordered_extent()
Removed, as now the ordered extent size limit is done at bio
allocation time, no need to check for each page range.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add try-lock for exclusive operation start to allow callers to do more
checks. The same operation must already be running. The try-lock and
unlock must pair and are a substitute for btrfs_exclop_start, thus it
must also pair with btrfs_exclop_finish to release the exclop context.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add support code that will allow canceling relocation on the chunk
granularity. This is different and independent of balance, that also
uses relocation but is a higher level operation and manages it's own
state and pause/cancellation requests.
Relocation is used for resize (shrink) and device deletion so this will
be a common point to implement cancellation for both. The context is
entirely in btrfs_relocate_block_group and btrfs_recover_relocation,
enclosing one chunk relocation. The status bit is set and unset between
the chunks. As relocation can take long, the effects may not be
immediate and the request and actual action can slightly race.
The fs_info::reloc_cancel_req is only supposed to be increased and does
not pair with decrement like fs_info::balance_cancel_req.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The exclusive operation is now atomically checked and set using bit
operations. Switch it to protection by spinlock. The super block lock is
not frequently used and adding a new lock seems like an overkill so it
should be safe to reuse it.
The reason to use spinlock is to enhance the locking context so more
checks can be done, eg. allowing the same exclusive operation enter
the exclop section and cancel the running one. This will be used for
resize and device delete.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At btrfs_truncate() where we truncate the inode either to the same size
or to a smaller size, we always set the full sync flag on the inode.
This is needed in case the truncation drops or trims any file extent items
that start beyond or cross the new inode size, so that the next fsync
drops all inode items from the log and scans again the fs/subvolume tree
to find all items that must be logged.
However if the truncation does not drop or trims any file extent items, we
do not need to set the full sync flag and force the next fsync to use the
slow code path. So do not set the full sync flag in such cases.
One use case where it is frequent to do truncations that do not change
the inode size and do not drop any extents (no prealloc extents beyond
i_size) is when running Microsoft's SQL Server inside a Docker container.
One example workload is the one Philipp Fent reported recently, in the
thread with a link below. In this workload a large number of fsyncs are
preceded by such truncate operations.
After this change I constantly get the runtime for that workload from
Philipp to be reduced by about -12%, for example from 184 seconds down
to 162 seconds.
Link: https://lore.kernel.org/linux-btrfs/93c4600e-5263-5cba-adf0-6f47526e7561@in.tum.de/
Tested-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This will provide the basis for later per-sector repair for subpage,
while still keeping the existing code happy.
As if all csums match, the return value will be 0, same as now.
Only when csum mismatches, the return value is different.
The new return value will be a bitmap, for 4K sectorsize and 4K page
size, it will be either 1, instead of the -EIO (which is not used
directly by the callers, no effective change).
But for 4K sectorsize and 64K page size, aka subpage case, since the
bvec can contain multiple sectors, knowing which sectors are corrupted
will allow us to submit repair only for corrupted sectors.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-5.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"First batch of various fixes, here's a list of notable ones:
- fix unmountable seed device after fstrim
- fix silent data loss in zoned mode due to ordered extent splitting
- fix race leading to unpersisted data and metadata on fsync
- fix deadlock when cloning inline extents and using qgroups"
* tag 'for-5.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: initialize return variable in cleanup_free_space_cache_v1
btrfs: zoned: sanity check zone type
btrfs: fix unmountable seed device after fstrim
btrfs: fix deadlock when cloning inline extents and using qgroups
btrfs: fix race leading to unpersisted data and metadata on fsync
btrfs: do not consider send context as valid when trying to flush qgroups
btrfs: zoned: fix silent data loss after failure splitting ordered extent
There are a few exceptional cases where cloning an inline extent needs to
copy the inline extent data into a page of the destination inode.
When this happens, we end up starting a transaction while having a dirty
page for the destination inode and while having the range locked in the
destination's inode iotree too. Because when reserving metadata space
for a transaction we may need to flush existing delalloc in case there is
not enough free space, we have a mechanism in place to prevent a deadlock,
which was introduced in commit 3d45f221ce ("btrfs: fix deadlock when
cloning inline extent and low on free metadata space").
However when using qgroups, a transaction also reserves metadata qgroup
space, which can also result in flushing delalloc in case there is not
enough available space at the moment. When this happens we deadlock, since
flushing delalloc requires locking the file range in the inode's iotree
and the range was already locked at the very beginning of the clone
operation, before attempting to start the transaction.
When this issue happens, stack traces like the following are reported:
[72747.556262] task:kworker/u81:9 state:D stack: 0 pid: 225 ppid: 2 flags:0x00004000
[72747.556268] Workqueue: writeback wb_workfn (flush-btrfs-1142)
[72747.556271] Call Trace:
[72747.556273] __schedule+0x296/0x760
[72747.556277] schedule+0x3c/0xa0
[72747.556279] io_schedule+0x12/0x40
[72747.556284] __lock_page+0x13c/0x280
[72747.556287] ? generic_file_readonly_mmap+0x70/0x70
[72747.556325] extent_write_cache_pages+0x22a/0x440 [btrfs]
[72747.556331] ? __set_page_dirty_nobuffers+0xe7/0x160
[72747.556358] ? set_extent_buffer_dirty+0x5e/0x80 [btrfs]
[72747.556362] ? update_group_capacity+0x25/0x210
[72747.556366] ? cpumask_next_and+0x1a/0x20
[72747.556391] extent_writepages+0x44/0xa0 [btrfs]
[72747.556394] do_writepages+0x41/0xd0
[72747.556398] __writeback_single_inode+0x39/0x2a0
[72747.556403] writeback_sb_inodes+0x1ea/0x440
[72747.556407] __writeback_inodes_wb+0x5f/0xc0
[72747.556410] wb_writeback+0x235/0x2b0
[72747.556414] ? get_nr_inodes+0x35/0x50
[72747.556417] wb_workfn+0x354/0x490
[72747.556420] ? newidle_balance+0x2c5/0x3e0
[72747.556424] process_one_work+0x1aa/0x340
[72747.556426] worker_thread+0x30/0x390
[72747.556429] ? create_worker+0x1a0/0x1a0
[72747.556432] kthread+0x116/0x130
[72747.556435] ? kthread_park+0x80/0x80
[72747.556438] ret_from_fork+0x1f/0x30
[72747.566958] Workqueue: btrfs-flush_delalloc btrfs_work_helper [btrfs]
[72747.566961] Call Trace:
[72747.566964] __schedule+0x296/0x760
[72747.566968] ? finish_wait+0x80/0x80
[72747.566970] schedule+0x3c/0xa0
[72747.566995] wait_extent_bit.constprop.68+0x13b/0x1c0 [btrfs]
[72747.566999] ? finish_wait+0x80/0x80
[72747.567024] lock_extent_bits+0x37/0x90 [btrfs]
[72747.567047] btrfs_invalidatepage+0x299/0x2c0 [btrfs]
[72747.567051] ? find_get_pages_range_tag+0x2cd/0x380
[72747.567076] __extent_writepage+0x203/0x320 [btrfs]
[72747.567102] extent_write_cache_pages+0x2bb/0x440 [btrfs]
[72747.567106] ? update_load_avg+0x7e/0x5f0
[72747.567109] ? enqueue_entity+0xf4/0x6f0
[72747.567134] extent_writepages+0x44/0xa0 [btrfs]
[72747.567137] ? enqueue_task_fair+0x93/0x6f0
[72747.567140] do_writepages+0x41/0xd0
[72747.567144] __filemap_fdatawrite_range+0xc7/0x100
[72747.567167] btrfs_run_delalloc_work+0x17/0x40 [btrfs]
[72747.567195] btrfs_work_helper+0xc2/0x300 [btrfs]
[72747.567200] process_one_work+0x1aa/0x340
[72747.567202] worker_thread+0x30/0x390
[72747.567205] ? create_worker+0x1a0/0x1a0
[72747.567208] kthread+0x116/0x130
[72747.567211] ? kthread_park+0x80/0x80
[72747.567214] ret_from_fork+0x1f/0x30
[72747.569686] task:fsstress state:D stack: 0 pid:841421 ppid:841417 flags:0x00000000
[72747.569689] Call Trace:
[72747.569691] __schedule+0x296/0x760
[72747.569694] schedule+0x3c/0xa0
[72747.569721] try_flush_qgroup+0x95/0x140 [btrfs]
[72747.569725] ? finish_wait+0x80/0x80
[72747.569753] btrfs_qgroup_reserve_data+0x34/0x50 [btrfs]
[72747.569781] btrfs_check_data_free_space+0x5f/0xa0 [btrfs]
[72747.569804] btrfs_buffered_write+0x1f7/0x7f0 [btrfs]
[72747.569810] ? path_lookupat.isra.48+0x97/0x140
[72747.569833] btrfs_file_write_iter+0x81/0x410 [btrfs]
[72747.569836] ? __kmalloc+0x16a/0x2c0
[72747.569839] do_iter_readv_writev+0x160/0x1c0
[72747.569843] do_iter_write+0x80/0x1b0
[72747.569847] vfs_writev+0x84/0x140
[72747.569869] ? btrfs_file_llseek+0x38/0x270 [btrfs]
[72747.569873] do_writev+0x65/0x100
[72747.569876] do_syscall_64+0x33/0x40
[72747.569879] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[72747.569899] task:fsstress state:D stack: 0 pid:841424 ppid:841417 flags:0x00004000
[72747.569903] Call Trace:
[72747.569906] __schedule+0x296/0x760
[72747.569909] schedule+0x3c/0xa0
[72747.569936] try_flush_qgroup+0x95/0x140 [btrfs]
[72747.569940] ? finish_wait+0x80/0x80
[72747.569967] __btrfs_qgroup_reserve_meta+0x36/0x50 [btrfs]
[72747.569989] start_transaction+0x279/0x580 [btrfs]
[72747.570014] clone_copy_inline_extent+0x332/0x490 [btrfs]
[72747.570041] btrfs_clone+0x5b7/0x7a0 [btrfs]
[72747.570068] ? lock_extent_bits+0x64/0x90 [btrfs]
[72747.570095] btrfs_clone_files+0xfc/0x150 [btrfs]
[72747.570122] btrfs_remap_file_range+0x3d8/0x4a0 [btrfs]
[72747.570126] do_clone_file_range+0xed/0x200
[72747.570131] vfs_clone_file_range+0x37/0x110
[72747.570134] ioctl_file_clone+0x7d/0xb0
[72747.570137] do_vfs_ioctl+0x138/0x630
[72747.570140] __x64_sys_ioctl+0x62/0xc0
[72747.570143] do_syscall_64+0x33/0x40
[72747.570146] entry_SYSCALL_64_after_hwframe+0x44/0xa9
So fix this by skipping the flush of delalloc for an inode that is
flagged with BTRFS_INODE_NO_DELALLOC_FLUSH, meaning it is currently under
such a special case of cloning an inline extent, when flushing delalloc
during qgroup metadata reservation.
The special cases for cloning inline extents were added in kernel 5.7 by
by commit 05a5a7621c ("Btrfs: implement full reflink support for
inline extents"), while having qgroup metadata space reservation flushing
delalloc when low on space was added in kernel 5.9 by commit
c53e965360 ("btrfs: qgroup: try to flush qgroup space when we get
-EDQUOT"). So use a "Fixes:" tag for the later commit to ease stable
kernel backports.
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Link: https://lore.kernel.org/linux-btrfs/20210421083137.31E3.409509F4@e16-tech.com/
Fixes: c53e965360 ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT")
CC: stable@vger.kernel.org # 5.9+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull fileattr conversion updates from Miklos Szeredi via Al Viro:
"This splits the handling of FS_IOC_[GS]ETFLAGS from ->ioctl() into a
separate method.
The interface is reasonably uniform across the filesystems that
support it and gives nice boilerplate removal"
* 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (23 commits)
ovl: remove unneeded ioctls
fuse: convert to fileattr
fuse: add internal open/release helpers
fuse: unsigned open flags
fuse: move ioctl to separate source file
vfs: remove unused ioctl helpers
ubifs: convert to fileattr
reiserfs: convert to fileattr
ocfs2: convert to fileattr
nilfs2: convert to fileattr
jfs: convert to fileattr
hfsplus: convert to fileattr
efivars: convert to fileattr
xfs: convert to fileattr
orangefs: convert to fileattr
gfs2: convert to fileattr
f2fs: convert to fileattr
ext4: convert to fileattr
ext2: convert to fileattr
btrfs: convert to fileattr
...
When a file gets deleted on a zoned file system, the space freed is not
returned back into the block group's free space, but is migrated to
zone_unusable.
As this zone_unusable space is behind the current write pointer it is not
possible to use it for new allocations. In the current implementation a
zone is reset once all of the block group's space is accounted as zone
unusable.
This behaviour can lead to premature ENOSPC errors on a busy file system.
Instead of only reclaiming the zone once it is completely unusable,
kick off a reclaim job once the amount of unusable bytes exceeds a user
configurable threshold between 51% and 100%. It can be set per mounted
filesystem via the sysfs tunable bg_reclaim_threshold which is set to 75%
by default.
Similar to reclaiming unused block groups, these dirty block groups are
added to a to_reclaim list and then on a transaction commit, the reclaim
process is triggered but after we deleted unused block groups, which will
free space for the relocation process.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As a preparation for extending the block group deletion use case, rename
the unused_bgs_mutex to reclaim_bgs_lock.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs uses internally mapped u64 address space for all its metadata.
Due to the page cache limit on 32bit systems, btrfs can't access
metadata at or beyond (ULONG_MAX + 1) << PAGE_SHIFT. See
how MAX_LFS_FILESIZE and page::index are defined. This is 16T for 4K
page size while 256T for 64K page size.
Users can have a filesystem which doesn't have metadata beyond the
boundary at mount time, but later balance can cause it to create
metadata beyond the boundary.
And modification to MM layer is unrealistic just for such minor use
case. We can't do more than to prevent mounting such filesystem or warn
early when the numbers are still within the limits.
To address such problem, this patch will introduce the following checks:
- Mount time rejection
This will reject any fs which has metadata chunk at or beyond the
boundary.
- Mount time early warning
If there is any metadata chunk beyond 5/8th of the boundary, we do an
early warning and hope the end user will see it.
- Runtime extent buffer rejection
If we're going to allocate an extent buffer at or beyond the boundary,
reject such request with EOVERFLOW.
This is definitely going to cause problems like transaction abort, but
we have no better ways.
- Runtime extent buffer early warning
If an extent buffer beyond 5/8th of the max file size is allocated, do
an early warning.
Above error/warning message will only be printed once for each fs to
reduce dmesg flood.
If the mount is rejected, the filesystem will be mountable only on a
64bit host.
Link: https://lore.kernel.org/linux-btrfs/1783f16d-7a28-80e6-4c32-fdf19b705ed0@gmx.com/
Reported-by: Erik Jensen <erikjensen@rkjnsn.net>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently a full send operation uses the standard btree readahead when
iterating over the subvolume/snapshot btree, which despite bringing good
performance benefits, it could be improved in a few aspects for use cases
such as full send operations, which are guaranteed to visit every node
and leaf of a btree, in ascending and sequential order. The limitations
of that standard btree readahead implementation are the following:
1) It only triggers readahead for leaves that are physically close
to the leaf being read, within a 64K range;
2) It only triggers readahead for the next or previous leaves if the
leaf being read is not currently in memory;
3) It never triggers readahead for nodes.
So add a new readahead mode that addresses all these points and use it
for full send operations.
The following test script was used to measure the improvement on a box
using an average, consumer grade, spinning disk and with 16GiB of RAM:
$ cat test.sh
#!/bin/bash
DEV=/dev/sdj
MNT=/mnt/sdj
MKFS_OPTIONS="--nodesize 16384" # default, just to be explicit
MOUNT_OPTIONS="-o max_inline=2048" # default, just to be explicit
mkfs.btrfs -f $MKFS_OPTIONS $DEV > /dev/null
mount $MOUNT_OPTIONS $DEV $MNT
# Create files with inline data to make it easier and faster to create
# large btrees.
add_files()
{
local total=$1
local start_offset=$2
local number_jobs=$3
local total_per_job=$(($total / $number_jobs))
echo "Creating $total new files using $number_jobs jobs"
for ((n = 0; n < $number_jobs; n++)); do
(
local start_num=$(($start_offset + $n * $total_per_job))
for ((i = 1; i <= $total_per_job; i++)); do
local file_num=$((start_num + $i))
local file_path="$MNT/file_${file_num}"
xfs_io -f -c "pwrite -S 0xab 0 2000" $file_path > /dev/null
if [ $? -ne 0 ]; then
echo "Failed creating file $file_path"
break
fi
done
) &
worker_pids[$n]=$!
done
wait ${worker_pids[@]}
sync
echo
echo "btree node/leaf count: $(btrfs inspect-internal dump-tree -t 5 $DEV | egrep '^(node|leaf) ' | wc -l)"
}
initial_file_count=500000
add_files $initial_file_count 0 4
echo
echo "Creating first snapshot..."
btrfs subvolume snapshot -r $MNT $MNT/snap1
echo
echo "Adding more files..."
add_files $((initial_file_count / 4)) $initial_file_count 4
echo
echo "Updating 1/50th of the initial files..."
for ((i = 1; i < $initial_file_count; i += 50)); do
xfs_io -c "pwrite -S 0xcd 0 20" $MNT/file_$i > /dev/null
done
echo
echo "Creating second snapshot..."
btrfs subvolume snapshot -r $MNT $MNT/snap2
umount $MNT
echo 3 > /proc/sys/vm/drop_caches
blockdev --flushbufs $DEV &> /dev/null
hdparm -F $DEV &> /dev/null
mount $MOUNT_OPTIONS $DEV $MNT
echo
echo "Testing full send..."
start=$(date +%s)
btrfs send $MNT/snap1 > /dev/null
end=$(date +%s)
echo
echo "Full send took $((end - start)) seconds"
umount $MNT
The durations of the full send operation in seconds were the following:
Before this change: 217 seconds
After this change: 205 seconds (-5.7%)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The tree modification log functions are called very frequently, basically
they are called every time a btree is modified (a pointer added or removed
to a node, a new root for a btree is set, etc). Because of that, to avoid
heavy lock contention on the lock that protects the list of tree mod log
users, we have checks that test the emptiness of the list with a full
memory barrier before the checks, so that when there are no tree mod log
users we avoid taking the lock.
Replace the memory barrier and list emptiness check with a test for a new
bit set at fs_info->flags. This bit is used to indicate when there are
tree mod log users, set whenever a user is added to the list and cleared
when the last user is removed from the list. This makes the intention a
bit more obvious and possibly more efficient (assuming test_bit() may be
cheaper than a full memory barrier on some architectures).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The tree modification log, which records modifications done to btrees, is
quite large and currently spread all over ctree.c, which is a huge file
already.
To make things better organized, move all that code into its own separate
source and header files. Functions and definitions that are used outside
of the module (mostly by ctree.c) are renamed so that they start with a
"btrfs_" prefix. Everything else remains unchanged.
This makes it easier to go over the tree modification log code every
time I need to go read it to fix a bug.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
The in_range() macro is defined twice in btrfs' source, once in ctree.h
and once in misc.h.
Remove the definition in ctree.h and include misc.h in the files depending
on it.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We need to be able to exclude page_mkwrite from happening concurrently
with certain operations. To facilitate this, add a i_mmap_lock to our
inode, down_read() it in our mkwrite, and add a new ILOCK flag to
indicate that we want to take the i_mmap_lock as well. I used pahole to
check the size of the btrfs_inode, the sizes are as follows
no lockdep:
before: 1120 (3 per 4k page)
after: 1160 (3 per 4k page)
lockdep:
before: 2072 (1 per 4k page)
after: 2224 (1 per 4k page)
We're slightly larger but it doesn't change how many objects we can fit
per page.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The parameter mirror is not used and does not make sense for checksum
verification of the given bio.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_extent_readonly() is used by can_nocow_extent() in inode.c. So
move it from extent-tree.c to inode.c and declare it as static.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use the fileattr API to let the VFS handle locking, permission checking and
conversion.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: David Sterba <dsterba@suse.com>
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Merge tag 'for-5.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"This is the first batch of fixes that usually arrive during the merge
window code freeze. Regressions and stable material.
Regressions:
- fix deadlock in log sync in zoned mode
- fix bugs in subpage mode still wrongly assuming sectorsize == page
size
Fixes:
- fix missing kunmap of the Q stripe in RAID6
- block group fixes:
- fix race between extent freeing/allocation when using bitmaps
- avoid double put of block group when emptying cluster
- swapfile fixes:
- fix swapfile writes vs running scrub
- fix swapfile activation vs snapshot creation
- fix stale data exposure after cloning a hole with NO_HOLES enabled
- remove tree-checker check that does not work in case information
from other leaves is necessary"
* tag 'for-5.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: zoned: fix deadlock on log sync
btrfs: avoid double put of block group when emptying cluster
btrfs: fix stale data exposure after cloning a hole with NO_HOLES enabled
btrfs: tree-checker: do not error out if extent ref hash doesn't match
btrfs: fix race between swap file activation and snapshot creation
btrfs: fix race between writes to swap files and scrub
btrfs: avoid checking for RO block group twice during nocow writeback
btrfs: fix race between extent freeing/allocation when using bitmaps
btrfs: make check_compressed_csum() to be subpage compatible
btrfs: make btrfs_submit_compressed_read() subpage compatible
btrfs: fix raid6 qstripe kmap
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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
When we active a swap file, at btrfs_swap_activate(), we acquire the
exclusive operation lock to prevent the physical location of the swap
file extents to be changed by operations such as balance and device
replace/resize/remove. We also call there can_nocow_extent() which,
among other things, checks if the block group of a swap file extent is
currently RO, and if it is we can not use the extent, since a write
into it would result in COWing the extent.
However we have no protection against a scrub operation running after we
activate the swap file, which can result in the swap file extents to be
COWed while the scrub is running and operating on the respective block
group, because scrub turns a block group into RO before it processes it
and then back again to RW mode after processing it. That means an attempt
to write into a swap file extent while scrub is processing the respective
block group, will result in COWing the extent, changing its physical
location on disk.
Fix this by making sure that block groups that have extents that are used
by active swap files can not be turned into RO mode, therefore making it
not possible for a scrub to turn them into RO mode. When a scrub finds a
block group that can not be turned to RO due to the existence of extents
used by swap files, it proceeds to the next block group and logs a warning
message that mentions the block group was skipped due to active swap
files - this is the same approach we currently use for balance.
Fixes: ed46ff3d42 ("Btrfs: support swap files")
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This final patch adds the ZONED incompat flag to the supported flags
and enables to mount ZONED flagged file system.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is the 1/3 patch to enable tree log on zoned filesystems.
The tree-log feature does not work on a zoned filesystem as is. Blocks for
a tree-log tree are allocated mixed with other metadata blocks and btrfs
writes and syncs the tree-log blocks to devices at the time of fsync(),
which has a different timing than a global transaction commit. As a
result, both writing tree-log blocks and writing other metadata blocks
become non-sequential writes that zoned filesystems must avoid.
Introduce a dedicated block group for tree-log blocks, so that tree-log
blocks and other metadata blocks can be separate write streams. As a
result, each write stream can now be written to devices separately.
"fs_info->treelog_bg" tracks the dedicated block group and assigns
"treelog_bg" on-demand on tree-log block allocation time.
This commit extends the zoned block allocator to use the block group.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We cannot use zone append for writing metadata, because the B-tree nodes
have references to each other using logical address. Without knowing
the address in advance, we cannot construct the tree in the first place.
So we need to serialize write IOs for metadata.
We cannot add a mutex around allocation and submission because metadata
blocks are allocated in an earlier stage to build up B-trees.
Add a zoned_meta_io_lock and hold it during metadata IO submission in
btree_write_cache_pages() to serialize IOs.
Furthermore, this adds a per-block group metadata IO submission pointer
"meta_write_pointer" to ensure sequential writing, which can break when
attempting to write back blocks in an unfinished transaction. If the
writing out failed because of a hole and the write out is for data
integrity (WB_SYNC_ALL), it returns EAGAIN.
A caller like fsync() code should handle this properly e.g. by falling
back to a full transaction commit.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
To ensure that an ordered extent maps to a contiguous region on disk, we
need to maintain a "one bio == one ordered extent" rule.
Ensure that constructing bio does not span more than an ordered extent.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently if we ever have to flush space because we do not have enough
we allocate a ticket and attach it to the space_info, and then
systematically flush things in the filesystem that hold space
reservations until our space is reclaimed.
However this has a latency cost, we must go to sleep and wait for the
flushing to make progress before we are woken up and allowed to continue
doing our work.
In order to address that we used to kick off the async worker to flush
space preemptively, so that we could be reclaiming space hopefully
before any tasks needed to stop and wait for space to reclaim.
When I introduced the ticketed ENOSPC stuff this broke slightly in the
fact that we were using tickets to indicate if we were done flushing.
No tickets, no more flushing. However this meant that we essentially
never preemptively flushed. This caused a write performance regression
that Nikolay noticed in an unrelated patch that removed the committing
of the transaction during btrfs_end_transaction.
The behavior that happened pre that patch was btrfs_end_transaction()
would see that we were low on space, and it would commit the
transaction. This was bad because in this particular case you could end
up with thousands and thousands of transactions being committed during
the 5 minute reproducer. With the patch to remove this behavior we got
much more sane transaction commits, but we ended up slower because we
would write for a while, flush, write for a while, flush again.
To address this we need to reinstate a preemptive flushing mechanism.
However it is distinctly different from our ticketing flushing in that
it doesn't have tickets to base it's decisions on. Instead of bolting
this logic into our existing flushing work, add another worker to handle
this preemptive flushing. Here we will attempt to be slightly
intelligent about the things that we flushing, attempting to balance
between whichever pool is taking up the most space.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Solely for preemptive flushing, we want to be able to force the
transaction commit without any of the ambiguity of
may_commit_transaction(). This is because may_commit_transaction()
checks tickets and such, and in preemptive flushing we already know
it'll be helpful, so use this to keep the code nice and clean and
straightforward.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
We track dio_bytes because the shrink delalloc code needs to know if we
have more DIO in flight than we have normal buffered IO. The reason for
this is because we can't "flush" DIO, we have to just wait on the
ordered extents to finish.
However this is true of all ordered extents. If we have more ordered
space outstanding than dirty pages we should be waiting on ordered
extents. We already are ok on this front technically, because we always
do a FLUSH_DELALLOC_WAIT loop, but I want to use the ordered counter in
the preemptive flushing code as well, so change this to count all
ordered bytes instead of just DIO ordered bytes.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's currently u64 which gets instantly translated either to LONG_MAX
(if U64_MAX is passed) or cast to an unsigned long (which is in fact,
wrong because writeback_control::nr_to_write is a signed, long type).
Just convert the function's argument to be long time which obviates the
need to manually convert u64 value to a long. Adjust all call sites
which pass U64_MAX to pass LONG_MAX. Finally ensure that in
shrink_delalloc the u64 is converted to a long without overflowing,
resulting in a negative number.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's no longer used. While at it also remove new_dirid in create_subvol
as it's used in a single place and open code it. No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This reflects the true purpose of the member as it's being used solely
in context where a new objectid is being allocated. Future changes will
also change the way it's being used to closely follow this semantics.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-5.11-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A few more fixes for a late rc:
- fix lockdep complaint on 32bit arches and also remove an unsafe
memory use due to device vs filesystem lifetime
- two fixes for free space tree:
* race during log replay and cache rebuild, now more likely to
happen due to changes in this dev cycle
* possible free space tree corruption with online conversion
during initial tree population"
* tag 'for-5.11-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix log replay failure due to race with space cache rebuild
btrfs: fix lockdep warning due to seqcount_mutex on 32bit arch
btrfs: fix possible free space tree corruption with online conversion
While running btrfs/011 in a loop I would often ASSERT() while trying to
add a new free space entry that already existed, or get an EEXIST while
adding a new block to the extent tree, which is another indication of
double allocation.
This occurs because when we do the free space tree population, we create
the new root and then populate the tree and commit the transaction.
The problem is when you create a new root, the root node and commit root
node are the same. During this initial transaction commit we will run
all of the delayed refs that were paused during the free space tree
generation, and thus begin to cache block groups. While caching block
groups the caching thread will be reading from the main root for the
free space tree, so as we make allocations we'll be changing the free
space tree, which can cause us to add the same range twice which results
in either the ASSERT(ret != -EEXIST); in __btrfs_add_free_space, or in a
variety of different errors when running delayed refs because of a
double allocation.
Fix this by marking the fs_info as unsafe to load the free space tree,
and fall back on the old slow method. We could be smarter than this,
for example caching the block group while we're populating the free
space tree, but since this is a serious problem I've opted for the
simplest solution.
CC: stable@vger.kernel.org # 4.9+
Fixes: a5ed918285 ("Btrfs: implement the free space B-tree")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.
As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.
Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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Merge tag 'for-5.11-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A few more fixes that arrived before the end of the year:
- a bunch of fixes related to transaction handle lifetime wrt various
operations (umount, remount, qgroup scan, orphan cleanup)
- async discard scheduling fixes
- fix item size calculation when item keys collide for extend refs
(hardlinks)
- fix qgroup flushing from running transaction
- fix send, wrong file path when there is an inode with a pending
rmdir
- fix deadlock when cloning inline extent and low on free metadata
space"
* tag 'for-5.11-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: run delayed iputs when remounting RO to avoid leaking them
btrfs: add assertion for empty list of transactions at late stage of umount
btrfs: fix race between RO remount and the cleaner task
btrfs: fix transaction leak and crash after cleaning up orphans on RO mount
btrfs: fix transaction leak and crash after RO remount caused by qgroup rescan
btrfs: merge critical sections of discard lock in workfn
btrfs: fix racy access to discard_ctl data
btrfs: fix async discard stall
btrfs: tests: initialize test inodes location
btrfs: send: fix wrong file path when there is an inode with a pending rmdir
btrfs: qgroup: don't try to wait flushing if we're already holding a transaction
btrfs: correctly calculate item size used when item key collision happens
btrfs: fix deadlock when cloning inline extent and low on free metadata space
When we are remounting a filesystem in RO mode we can race with the cleaner
task and result in leaking a transaction if the filesystem is unmounted
shortly after, before the transaction kthread had a chance to commit that
transaction. That also results in a crash during unmount, due to a
use-after-free, if hardware acceleration is not available for crc32c.
The following sequence of steps explains how the race happens.
1) The filesystem is mounted in RW mode and the cleaner task is running.
This means that currently BTRFS_FS_CLEANER_RUNNING is set at
fs_info->flags;
2) The cleaner task is currently running delayed iputs for example;
3) A filesystem RO remount operation starts;
4) The RO remount task calls btrfs_commit_super(), which commits any
currently open transaction, and it finishes;
5) At this point the cleaner task is still running and it creates a new
transaction by doing one of the following things:
* When running the delayed iput() for an inode with a 0 link count,
in which case at btrfs_evict_inode() we start a transaction through
the call to evict_refill_and_join(), use it and then release its
handle through btrfs_end_transaction();
* When deleting a dead root through btrfs_clean_one_deleted_snapshot(),
a transaction is started at btrfs_drop_snapshot() and then its handle
is released through a call to btrfs_end_transaction_throttle();
* When the remount task was still running, and before the remount task
called btrfs_delete_unused_bgs(), the cleaner task also called
btrfs_delete_unused_bgs() and it picked and removed one block group
from the list of unused block groups. Before the cleaner task started
a transaction, through btrfs_start_trans_remove_block_group() at
btrfs_delete_unused_bgs(), the remount task had already called
btrfs_commit_super();
6) So at this point the filesystem is in RO mode and we have an open
transaction that was started by the cleaner task;
7) Shortly after a filesystem unmount operation starts. At close_ctree()
we stop the transaction kthread before it had a chance to commit the
transaction, since less than 30 seconds (the default commit interval)
have elapsed since the last transaction was committed;
8) We end up calling iput() against the btree inode at close_ctree() while
there is an open transaction, and since that transaction was used to
update btrees by the cleaner, we have dirty pages in the btree inode
due to COW operations on metadata extents, and therefore writeback is
triggered for the btree inode.
So btree_write_cache_pages() is invoked to flush those dirty pages
during the final iput() on the btree inode. This results in creating a
bio and submitting it, which makes us end up at
btrfs_submit_metadata_bio();
9) At btrfs_submit_metadata_bio() we end up at the if-then-else branch
that calls btrfs_wq_submit_bio(), because check_async_write() returned
a value of 1. This value of 1 is because we did not have hardware
acceleration available for crc32c, so BTRFS_FS_CSUM_IMPL_FAST was not
set in fs_info->flags;
10) Then at btrfs_wq_submit_bio() we call btrfs_queue_work() against the
workqueue at fs_info->workers, which was already freed before by the
call to btrfs_stop_all_workers() at close_ctree(). This results in an
invalid memory access due to a use-after-free, leading to a crash.
When this happens, before the crash there are several warnings triggered,
since we have reserved metadata space in a block group, the delayed refs
reservation, etc:
------------[ cut here ]------------
WARNING: CPU: 4 PID: 1729896 at fs/btrfs/block-group.c:125 btrfs_put_block_group+0x63/0xa0 [btrfs]
Modules linked in: btrfs dm_snapshot dm_thin_pool (...)
CPU: 4 PID: 1729896 Comm: umount Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:btrfs_put_block_group+0x63/0xa0 [btrfs]
Code: f0 01 00 00 48 39 c2 75 (...)
RSP: 0018:ffffb270826bbdd8 EFLAGS: 00010206
RAX: 0000000000000001 RBX: ffff947ed73e4000 RCX: ffff947ebc8b29c8
RDX: 0000000000000001 RSI: ffffffffc0b150a0 RDI: ffff947ebc8b2800
RBP: ffff947ebc8b2800 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff947ed73e4110
R13: ffff947ed73e4160 R14: ffff947ebc8b2988 R15: dead000000000100
FS: 00007f15edfea840(0000) GS:ffff9481ad600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f37e2893320 CR3: 0000000138f68001 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
btrfs_free_block_groups+0x17f/0x2f0 [btrfs]
close_ctree+0x2ba/0x2fa [btrfs]
generic_shutdown_super+0x6c/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20 [btrfs]
deactivate_locked_super+0x31/0x70
cleanup_mnt+0x100/0x160
task_work_run+0x68/0xb0
exit_to_user_mode_prepare+0x1bb/0x1c0
syscall_exit_to_user_mode+0x4b/0x260
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f15ee221ee7
Code: ff 0b 00 f7 d8 64 89 01 48 (...)
RSP: 002b:00007ffe9470f0f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f15ee347264 RCX: 00007f15ee221ee7
RDX: ffffffffffffff78 RSI: 0000000000000000 RDI: 000056169701d000
RBP: 0000561697018a30 R08: 0000000000000000 R09: 00007f15ee2e2be0
R10: 000056169701efe0 R11: 0000000000000246 R12: 0000000000000000
R13: 000056169701d000 R14: 0000561697018b40 R15: 0000561697018c60
irq event stamp: 0
hardirqs last enabled at (0): [<0000000000000000>] 0x0
hardirqs last disabled at (0): [<ffffffff8bcae560>] copy_process+0x8a0/0x1d70
softirqs last enabled at (0): [<ffffffff8bcae560>] copy_process+0x8a0/0x1d70
softirqs last disabled at (0): [<0000000000000000>] 0x0
---[ end trace dd74718fef1ed5c6 ]---
------------[ cut here ]------------
WARNING: CPU: 2 PID: 1729896 at fs/btrfs/block-rsv.c:459 btrfs_release_global_block_rsv+0x70/0xc0 [btrfs]
Modules linked in: btrfs dm_snapshot dm_thin_pool (...)
CPU: 2 PID: 1729896 Comm: umount Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:btrfs_release_global_block_rsv+0x70/0xc0 [btrfs]
Code: 48 83 bb b0 03 00 00 00 (...)
RSP: 0018:ffffb270826bbdd8 EFLAGS: 00010206
RAX: 000000000033c000 RBX: ffff947ed73e4000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffffc0b0d8c1 RDI: 00000000ffffffff
RBP: ffff947ebc8b7000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff947ed73e4110
R13: ffff947ed73e5278 R14: dead000000000122 R15: dead000000000100
FS: 00007f15edfea840(0000) GS:ffff9481aca00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561a79f76e20 CR3: 0000000138f68006 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
btrfs_free_block_groups+0x24c/0x2f0 [btrfs]
close_ctree+0x2ba/0x2fa [btrfs]
generic_shutdown_super+0x6c/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20 [btrfs]
deactivate_locked_super+0x31/0x70
cleanup_mnt+0x100/0x160
task_work_run+0x68/0xb0
exit_to_user_mode_prepare+0x1bb/0x1c0
syscall_exit_to_user_mode+0x4b/0x260
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f15ee221ee7
Code: ff 0b 00 f7 d8 64 89 01 (...)
RSP: 002b:00007ffe9470f0f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f15ee347264 RCX: 00007f15ee221ee7
RDX: ffffffffffffff78 RSI: 0000000000000000 RDI: 000056169701d000
RBP: 0000561697018a30 R08: 0000000000000000 R09: 00007f15ee2e2be0
R10: 000056169701efe0 R11: 0000000000000246 R12: 0000000000000000
R13: 000056169701d000 R14: 0000561697018b40 R15: 0000561697018c60
irq event stamp: 0
hardirqs last enabled at (0): [<0000000000000000>] 0x0
hardirqs last disabled at (0): [<ffffffff8bcae560>] copy_process+0x8a0/0x1d70
softirqs last enabled at (0): [<ffffffff8bcae560>] copy_process+0x8a0/0x1d70
softirqs last disabled at (0): [<0000000000000000>] 0x0
---[ end trace dd74718fef1ed5c7 ]---
------------[ cut here ]------------
WARNING: CPU: 2 PID: 1729896 at fs/btrfs/block-group.c:3377 btrfs_free_block_groups+0x25d/0x2f0 [btrfs]
Modules linked in: btrfs dm_snapshot dm_thin_pool (...)
CPU: 5 PID: 1729896 Comm: umount Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:btrfs_free_block_groups+0x25d/0x2f0 [btrfs]
Code: ad de 49 be 22 01 00 (...)
RSP: 0018:ffffb270826bbde8 EFLAGS: 00010206
RAX: ffff947ebeae1d08 RBX: ffff947ed73e4000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffff947e9d823ae8 RDI: 0000000000000246
RBP: ffff947ebeae1d08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff947ebeae1c00
R13: ffff947ed73e5278 R14: dead000000000122 R15: dead000000000100
FS: 00007f15edfea840(0000) GS:ffff9481ad200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1475d98ea8 CR3: 0000000138f68005 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
close_ctree+0x2ba/0x2fa [btrfs]
generic_shutdown_super+0x6c/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20 [btrfs]
deactivate_locked_super+0x31/0x70
cleanup_mnt+0x100/0x160
task_work_run+0x68/0xb0
exit_to_user_mode_prepare+0x1bb/0x1c0
syscall_exit_to_user_mode+0x4b/0x260
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f15ee221ee7
Code: ff 0b 00 f7 d8 64 89 (...)
RSP: 002b:00007ffe9470f0f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f15ee347264 RCX: 00007f15ee221ee7
RDX: ffffffffffffff78 RSI: 0000000000000000 RDI: 000056169701d000
RBP: 0000561697018a30 R08: 0000000000000000 R09: 00007f15ee2e2be0
R10: 000056169701efe0 R11: 0000000000000246 R12: 0000000000000000
R13: 000056169701d000 R14: 0000561697018b40 R15: 0000561697018c60
irq event stamp: 0
hardirqs last enabled at (0): [<0000000000000000>] 0x0
hardirqs last disabled at (0): [<ffffffff8bcae560>] copy_process+0x8a0/0x1d70
softirqs last enabled at (0): [<ffffffff8bcae560>] copy_process+0x8a0/0x1d70
softirqs last disabled at (0): [<0000000000000000>] 0x0
---[ end trace dd74718fef1ed5c8 ]---
BTRFS info (device sdc): space_info 4 has 268238848 free, is not full
BTRFS info (device sdc): space_info total=268435456, used=114688, pinned=0, reserved=16384, may_use=0, readonly=65536
BTRFS info (device sdc): global_block_rsv: size 0 reserved 0
BTRFS info (device sdc): trans_block_rsv: size 0 reserved 0
BTRFS info (device sdc): chunk_block_rsv: size 0 reserved 0
BTRFS info (device sdc): delayed_block_rsv: size 0 reserved 0
BTRFS info (device sdc): delayed_refs_rsv: size 524288 reserved 0
And the crash, which only happens when we do not have crc32c hardware
acceleration, produces the following trace immediately after those
warnings:
stack segment: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
CPU: 2 PID: 1749129 Comm: umount Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:btrfs_queue_work+0x36/0x190 [btrfs]
Code: 54 55 53 48 89 f3 (...)
RSP: 0018:ffffb27082443ae8 EFLAGS: 00010282
RAX: 0000000000000004 RBX: ffff94810ee9ad90 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffff94810ee9ad90 RDI: ffff947ed8ee75a0
RBP: a56b6b6b6b6b6b6b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000001 R12: ffff947fa9b435a8
R13: ffff94810ee9ad90 R14: 0000000000000000 R15: ffff947e93dc0000
FS: 00007f3cfe974840(0000) GS:ffff9481ac600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1b42995a70 CR3: 0000000127638003 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
btrfs_wq_submit_bio+0xb3/0xd0 [btrfs]
btrfs_submit_metadata_bio+0x44/0xc0 [btrfs]
submit_one_bio+0x61/0x70 [btrfs]
btree_write_cache_pages+0x414/0x450 [btrfs]
? kobject_put+0x9a/0x1d0
? trace_hardirqs_on+0x1b/0xf0
? _raw_spin_unlock_irqrestore+0x3c/0x60
? free_debug_processing+0x1e1/0x2b0
do_writepages+0x43/0xe0
? lock_acquired+0x199/0x490
__writeback_single_inode+0x59/0x650
writeback_single_inode+0xaf/0x120
write_inode_now+0x94/0xd0
iput+0x187/0x2b0
close_ctree+0x2c6/0x2fa [btrfs]
generic_shutdown_super+0x6c/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20 [btrfs]
deactivate_locked_super+0x31/0x70
cleanup_mnt+0x100/0x160
task_work_run+0x68/0xb0
exit_to_user_mode_prepare+0x1bb/0x1c0
syscall_exit_to_user_mode+0x4b/0x260
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f3cfebabee7
Code: ff 0b 00 f7 d8 64 89 01 (...)
RSP: 002b:00007ffc9c9a05f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3cfecd1264 RCX: 00007f3cfebabee7
RDX: ffffffffffffff78 RSI: 0000000000000000 RDI: 0000562b6b478000
RBP: 0000562b6b473a30 R08: 0000000000000000 R09: 00007f3cfec6cbe0
R10: 0000562b6b479fe0 R11: 0000000000000246 R12: 0000000000000000
R13: 0000562b6b478000 R14: 0000562b6b473b40 R15: 0000562b6b473c60
Modules linked in: btrfs dm_snapshot dm_thin_pool (...)
---[ end trace dd74718fef1ed5cc ]---
Finally when we remove the btrfs module (rmmod btrfs), there are several
warnings about objects that were allocated from our slabs but were never
freed, consequence of the transaction that was never committed and got
leaked:
=============================================================================
BUG btrfs_delayed_ref_head (Tainted: G B W ): Objects remaining in btrfs_delayed_ref_head on __kmem_cache_shutdown()
-----------------------------------------------------------------------------
INFO: Slab 0x0000000094c2ae56 objects=24 used=2 fp=0x000000002bfa2521 flags=0x17fffc000010200
CPU: 5 PID: 1729921 Comm: rmmod Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x8d/0xb5
slab_err+0xb7/0xdc
? lock_acquired+0x199/0x490
__kmem_cache_shutdown+0x1ac/0x3c0
? lock_release+0x20e/0x4c0
kmem_cache_destroy+0x55/0x120
btrfs_delayed_ref_exit+0x11/0x35 [btrfs]
exit_btrfs_fs+0xa/0x59 [btrfs]
__x64_sys_delete_module+0x194/0x260
? fpregs_assert_state_consistent+0x1e/0x40
? exit_to_user_mode_prepare+0x55/0x1c0
? trace_hardirqs_on+0x1b/0xf0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f693e305897
Code: 73 01 c3 48 8b 0d f9 f5 (...)
RSP: 002b:00007ffcf73eb508 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 0000559df504f760 RCX: 00007f693e305897
RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559df504f7c8
RBP: 00007ffcf73eb568 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f693e378ac0 R11: 0000000000000206 R12: 00007ffcf73eb740
R13: 00007ffcf73ec5a6 R14: 0000559df504f2a0 R15: 0000559df504f760
INFO: Object 0x0000000050cbdd61 @offset=12104
INFO: Allocated in btrfs_add_delayed_tree_ref+0xbb/0x480 [btrfs] age=1894 cpu=6 pid=1729873
__slab_alloc.isra.0+0x109/0x1c0
kmem_cache_alloc+0x7bb/0x830
btrfs_add_delayed_tree_ref+0xbb/0x480 [btrfs]
btrfs_free_tree_block+0x128/0x360 [btrfs]
__btrfs_cow_block+0x489/0x5f0 [btrfs]
btrfs_cow_block+0xf7/0x220 [btrfs]
btrfs_search_slot+0x62a/0xc40 [btrfs]
btrfs_del_orphan_item+0x65/0xd0 [btrfs]
btrfs_find_orphan_roots+0x1bf/0x200 [btrfs]
open_ctree+0x125a/0x18a0 [btrfs]
btrfs_mount_root.cold+0x13/0xed [btrfs]
legacy_get_tree+0x30/0x60
vfs_get_tree+0x28/0xe0
fc_mount+0xe/0x40
vfs_kern_mount.part.0+0x71/0x90
btrfs_mount+0x13b/0x3e0 [btrfs]
INFO: Freed in __btrfs_run_delayed_refs+0x1117/0x1290 [btrfs] age=4292 cpu=2 pid=1729526
kmem_cache_free+0x34c/0x3c0
__btrfs_run_delayed_refs+0x1117/0x1290 [btrfs]
btrfs_run_delayed_refs+0x81/0x210 [btrfs]
commit_cowonly_roots+0xfb/0x300 [btrfs]
btrfs_commit_transaction+0x367/0xc40 [btrfs]
sync_filesystem+0x74/0x90
generic_shutdown_super+0x22/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20 [btrfs]
deactivate_locked_super+0x31/0x70
cleanup_mnt+0x100/0x160
task_work_run+0x68/0xb0
exit_to_user_mode_prepare+0x1bb/0x1c0
syscall_exit_to_user_mode+0x4b/0x260
entry_SYSCALL_64_after_hwframe+0x44/0xa9
INFO: Object 0x0000000086e9b0ff @offset=12776
INFO: Allocated in btrfs_add_delayed_tree_ref+0xbb/0x480 [btrfs] age=1900 cpu=6 pid=1729873
__slab_alloc.isra.0+0x109/0x1c0
kmem_cache_alloc+0x7bb/0x830
btrfs_add_delayed_tree_ref+0xbb/0x480 [btrfs]
btrfs_alloc_tree_block+0x2bf/0x360 [btrfs]
alloc_tree_block_no_bg_flush+0x4f/0x60 [btrfs]
__btrfs_cow_block+0x12d/0x5f0 [btrfs]
btrfs_cow_block+0xf7/0x220 [btrfs]
btrfs_search_slot+0x62a/0xc40 [btrfs]
btrfs_del_orphan_item+0x65/0xd0 [btrfs]
btrfs_find_orphan_roots+0x1bf/0x200 [btrfs]
open_ctree+0x125a/0x18a0 [btrfs]
btrfs_mount_root.cold+0x13/0xed [btrfs]
legacy_get_tree+0x30/0x60
vfs_get_tree+0x28/0xe0
fc_mount+0xe/0x40
vfs_kern_mount.part.0+0x71/0x90
INFO: Freed in __btrfs_run_delayed_refs+0x1117/0x1290 [btrfs] age=3141 cpu=6 pid=1729803
kmem_cache_free+0x34c/0x3c0
__btrfs_run_delayed_refs+0x1117/0x1290 [btrfs]
btrfs_run_delayed_refs+0x81/0x210 [btrfs]
btrfs_write_dirty_block_groups+0x17d/0x3d0 [btrfs]
commit_cowonly_roots+0x248/0x300 [btrfs]
btrfs_commit_transaction+0x367/0xc40 [btrfs]
close_ctree+0x113/0x2fa [btrfs]
generic_shutdown_super+0x6c/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20 [btrfs]
deactivate_locked_super+0x31/0x70
cleanup_mnt+0x100/0x160
task_work_run+0x68/0xb0
exit_to_user_mode_prepare+0x1bb/0x1c0
syscall_exit_to_user_mode+0x4b/0x260
entry_SYSCALL_64_after_hwframe+0x44/0xa9
kmem_cache_destroy btrfs_delayed_ref_head: Slab cache still has objects
CPU: 5 PID: 1729921 Comm: rmmod Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x8d/0xb5
kmem_cache_destroy+0x119/0x120
btrfs_delayed_ref_exit+0x11/0x35 [btrfs]
exit_btrfs_fs+0xa/0x59 [btrfs]
__x64_sys_delete_module+0x194/0x260
? fpregs_assert_state_consistent+0x1e/0x40
? exit_to_user_mode_prepare+0x55/0x1c0
? trace_hardirqs_on+0x1b/0xf0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f693e305897
Code: 73 01 c3 48 8b 0d f9 f5 0b (...)
RSP: 002b:00007ffcf73eb508 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 0000559df504f760 RCX: 00007f693e305897
RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559df504f7c8
RBP: 00007ffcf73eb568 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f693e378ac0 R11: 0000000000000206 R12: 00007ffcf73eb740
R13: 00007ffcf73ec5a6 R14: 0000559df504f2a0 R15: 0000559df504f760
=============================================================================
BUG btrfs_delayed_tree_ref (Tainted: G B W ): Objects remaining in btrfs_delayed_tree_ref on __kmem_cache_shutdown()
-----------------------------------------------------------------------------
INFO: Slab 0x0000000011f78dc0 objects=37 used=2 fp=0x0000000032d55d91 flags=0x17fffc000010200
CPU: 3 PID: 1729921 Comm: rmmod Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x8d/0xb5
slab_err+0xb7/0xdc
? lock_acquired+0x199/0x490
__kmem_cache_shutdown+0x1ac/0x3c0
? lock_release+0x20e/0x4c0
kmem_cache_destroy+0x55/0x120
btrfs_delayed_ref_exit+0x1d/0x35 [btrfs]
exit_btrfs_fs+0xa/0x59 [btrfs]
__x64_sys_delete_module+0x194/0x260
? fpregs_assert_state_consistent+0x1e/0x40
? exit_to_user_mode_prepare+0x55/0x1c0
? trace_hardirqs_on+0x1b/0xf0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f693e305897
Code: 73 01 c3 48 8b 0d f9 f5 (...)
RSP: 002b:00007ffcf73eb508 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 0000559df504f760 RCX: 00007f693e305897
RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559df504f7c8
RBP: 00007ffcf73eb568 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f693e378ac0 R11: 0000000000000206 R12: 00007ffcf73eb740
R13: 00007ffcf73ec5a6 R14: 0000559df504f2a0 R15: 0000559df504f760
INFO: Object 0x000000001a340018 @offset=4408
INFO: Allocated in btrfs_add_delayed_tree_ref+0x9e/0x480 [btrfs] age=1917 cpu=6 pid=1729873
__slab_alloc.isra.0+0x109/0x1c0
kmem_cache_alloc+0x7bb/0x830
btrfs_add_delayed_tree_ref+0x9e/0x480 [btrfs]
btrfs_free_tree_block+0x128/0x360 [btrfs]
__btrfs_cow_block+0x489/0x5f0 [btrfs]
btrfs_cow_block+0xf7/0x220 [btrfs]
btrfs_search_slot+0x62a/0xc40 [btrfs]
btrfs_del_orphan_item+0x65/0xd0 [btrfs]
btrfs_find_orphan_roots+0x1bf/0x200 [btrfs]
open_ctree+0x125a/0x18a0 [btrfs]
btrfs_mount_root.cold+0x13/0xed [btrfs]
legacy_get_tree+0x30/0x60
vfs_get_tree+0x28/0xe0
fc_mount+0xe/0x40
vfs_kern_mount.part.0+0x71/0x90
btrfs_mount+0x13b/0x3e0 [btrfs]
INFO: Freed in __btrfs_run_delayed_refs+0x63d/0x1290 [btrfs] age=4167 cpu=4 pid=1729795
kmem_cache_free+0x34c/0x3c0
__btrfs_run_delayed_refs+0x63d/0x1290 [btrfs]
btrfs_run_delayed_refs+0x81/0x210 [btrfs]
btrfs_commit_transaction+0x60/0xc40 [btrfs]
create_subvol+0x56a/0x990 [btrfs]
btrfs_mksubvol+0x3fb/0x4a0 [btrfs]
__btrfs_ioctl_snap_create+0x119/0x1a0 [btrfs]
btrfs_ioctl_snap_create+0x58/0x80 [btrfs]
btrfs_ioctl+0x1a92/0x36f0 [btrfs]
__x64_sys_ioctl+0x83/0xb0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
INFO: Object 0x000000002b46292a @offset=13648
INFO: Allocated in btrfs_add_delayed_tree_ref+0x9e/0x480 [btrfs] age=1923 cpu=6 pid=1729873
__slab_alloc.isra.0+0x109/0x1c0
kmem_cache_alloc+0x7bb/0x830
btrfs_add_delayed_tree_ref+0x9e/0x480 [btrfs]
btrfs_alloc_tree_block+0x2bf/0x360 [btrfs]
alloc_tree_block_no_bg_flush+0x4f/0x60 [btrfs]
__btrfs_cow_block+0x12d/0x5f0 [btrfs]
btrfs_cow_block+0xf7/0x220 [btrfs]
btrfs_search_slot+0x62a/0xc40 [btrfs]
btrfs_del_orphan_item+0x65/0xd0 [btrfs]
btrfs_find_orphan_roots+0x1bf/0x200 [btrfs]
open_ctree+0x125a/0x18a0 [btrfs]
btrfs_mount_root.cold+0x13/0xed [btrfs]
legacy_get_tree+0x30/0x60
vfs_get_tree+0x28/0xe0
fc_mount+0xe/0x40
vfs_kern_mount.part.0+0x71/0x90
INFO: Freed in __btrfs_run_delayed_refs+0x63d/0x1290 [btrfs] age=3164 cpu=6 pid=1729803
kmem_cache_free+0x34c/0x3c0
__btrfs_run_delayed_refs+0x63d/0x1290 [btrfs]
btrfs_run_delayed_refs+0x81/0x210 [btrfs]
commit_cowonly_roots+0xfb/0x300 [btrfs]
btrfs_commit_transaction+0x367/0xc40 [btrfs]
close_ctree+0x113/0x2fa [btrfs]
generic_shutdown_super+0x6c/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20 [btrfs]
deactivate_locked_super+0x31/0x70
cleanup_mnt+0x100/0x160
task_work_run+0x68/0xb0
exit_to_user_mode_prepare+0x1bb/0x1c0
syscall_exit_to_user_mode+0x4b/0x260
entry_SYSCALL_64_after_hwframe+0x44/0xa9
kmem_cache_destroy btrfs_delayed_tree_ref: Slab cache still has objects
CPU: 5 PID: 1729921 Comm: rmmod Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x8d/0xb5
kmem_cache_destroy+0x119/0x120
btrfs_delayed_ref_exit+0x1d/0x35 [btrfs]
exit_btrfs_fs+0xa/0x59 [btrfs]
__x64_sys_delete_module+0x194/0x260
? fpregs_assert_state_consistent+0x1e/0x40
? exit_to_user_mode_prepare+0x55/0x1c0
? trace_hardirqs_on+0x1b/0xf0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f693e305897
Code: 73 01 c3 48 8b 0d f9 f5 (...)
RSP: 002b:00007ffcf73eb508 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 0000559df504f760 RCX: 00007f693e305897
RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559df504f7c8
RBP: 00007ffcf73eb568 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f693e378ac0 R11: 0000000000000206 R12: 00007ffcf73eb740
R13: 00007ffcf73ec5a6 R14: 0000559df504f2a0 R15: 0000559df504f760
=============================================================================
BUG btrfs_delayed_extent_op (Tainted: G B W ): Objects remaining in btrfs_delayed_extent_op on __kmem_cache_shutdown()
-----------------------------------------------------------------------------
INFO: Slab 0x00000000f145ce2f objects=22 used=1 fp=0x00000000af0f92cf flags=0x17fffc000010200
CPU: 5 PID: 1729921 Comm: rmmod Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x8d/0xb5
slab_err+0xb7/0xdc
? lock_acquired+0x199/0x490
__kmem_cache_shutdown+0x1ac/0x3c0
? __mutex_unlock_slowpath+0x45/0x2a0
kmem_cache_destroy+0x55/0x120
exit_btrfs_fs+0xa/0x59 [btrfs]
__x64_sys_delete_module+0x194/0x260
? fpregs_assert_state_consistent+0x1e/0x40
? exit_to_user_mode_prepare+0x55/0x1c0
? trace_hardirqs_on+0x1b/0xf0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f693e305897
Code: 73 01 c3 48 8b 0d f9 f5 (...)
RSP: 002b:00007ffcf73eb508 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 0000559df504f760 RCX: 00007f693e305897
RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559df504f7c8
RBP: 00007ffcf73eb568 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f693e378ac0 R11: 0000000000000206 R12: 00007ffcf73eb740
R13: 00007ffcf73ec5a6 R14: 0000559df504f2a0 R15: 0000559df504f760
INFO: Object 0x000000004cf95ea8 @offset=6264
INFO: Allocated in btrfs_alloc_tree_block+0x1e0/0x360 [btrfs] age=1931 cpu=6 pid=1729873
__slab_alloc.isra.0+0x109/0x1c0
kmem_cache_alloc+0x7bb/0x830
btrfs_alloc_tree_block+0x1e0/0x360 [btrfs]
alloc_tree_block_no_bg_flush+0x4f/0x60 [btrfs]
__btrfs_cow_block+0x12d/0x5f0 [btrfs]
btrfs_cow_block+0xf7/0x220 [btrfs]
btrfs_search_slot+0x62a/0xc40 [btrfs]
btrfs_del_orphan_item+0x65/0xd0 [btrfs]
btrfs_find_orphan_roots+0x1bf/0x200 [btrfs]
open_ctree+0x125a/0x18a0 [btrfs]
btrfs_mount_root.cold+0x13/0xed [btrfs]
legacy_get_tree+0x30/0x60
vfs_get_tree+0x28/0xe0
fc_mount+0xe/0x40
vfs_kern_mount.part.0+0x71/0x90
btrfs_mount+0x13b/0x3e0 [btrfs]
INFO: Freed in __btrfs_run_delayed_refs+0xabd/0x1290 [btrfs] age=3173 cpu=6 pid=1729803
kmem_cache_free+0x34c/0x3c0
__btrfs_run_delayed_refs+0xabd/0x1290 [btrfs]
btrfs_run_delayed_refs+0x81/0x210 [btrfs]
commit_cowonly_roots+0xfb/0x300 [btrfs]
btrfs_commit_transaction+0x367/0xc40 [btrfs]
close_ctree+0x113/0x2fa [btrfs]
generic_shutdown_super+0x6c/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20 [btrfs]
deactivate_locked_super+0x31/0x70
cleanup_mnt+0x100/0x160
task_work_run+0x68/0xb0
exit_to_user_mode_prepare+0x1bb/0x1c0
syscall_exit_to_user_mode+0x4b/0x260
entry_SYSCALL_64_after_hwframe+0x44/0xa9
kmem_cache_destroy btrfs_delayed_extent_op: Slab cache still has objects
CPU: 3 PID: 1729921 Comm: rmmod Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x8d/0xb5
kmem_cache_destroy+0x119/0x120
exit_btrfs_fs+0xa/0x59 [btrfs]
__x64_sys_delete_module+0x194/0x260
? fpregs_assert_state_consistent+0x1e/0x40
? exit_to_user_mode_prepare+0x55/0x1c0
? trace_hardirqs_on+0x1b/0xf0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f693e305897
Code: 73 01 c3 48 8b 0d f9 (...)
RSP: 002b:00007ffcf73eb508 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 0000559df504f760 RCX: 00007f693e305897
RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559df504f7c8
RBP: 00007ffcf73eb568 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f693e378ac0 R11: 0000000000000206 R12: 00007ffcf73eb740
R13: 00007ffcf73ec5a6 R14: 0000559df504f2a0 R15: 0000559df504f760
BTRFS: state leak: start 30408704 end 30425087 state 1 in tree 1 refs 1
So fix this by making the remount path to wait for the cleaner task before
calling btrfs_commit_super(). The remount path now waits for the bit
BTRFS_FS_CLEANER_RUNNING to be cleared from fs_info->flags before calling
btrfs_commit_super() and this ensures the cleaner can not start a
transaction after that, because it sleeps when the filesystem is in RO
mode and we have already flagged the filesystem as RO before waiting for
BTRFS_FS_CLEANER_RUNNING to be cleared.
This also introduces a new flag BTRFS_FS_STATE_RO to be used for
fs_info->fs_state when the filesystem is in RO mode. This is because we
were doing the RO check using the flags of the superblock and setting the
RO mode simply by ORing into the superblock's flags - those operations are
not atomic and could result in the cleaner not seeing the update from the
remount task after it clears BTRFS_FS_CLEANER_RUNNING.
Tested-by: Fabian Vogt <fvogt@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Item key collision is allowed for some item types, like dir item and
inode refs, but the overall item size is limited by the nodesize.
item size(ins_len) passed from btrfs_insert_empty_items to
btrfs_search_slot already contains size of btrfs_item.
When btrfs_search_slot reaches leaf, we'll see if we need to split leaf.
The check incorrectly reports that split leaf is required, because
it treats the space required by the newly inserted item as
btrfs_item + item data. But in item key collision case, only item data
is actually needed, the newly inserted item could merge into the existing
one. No new btrfs_item will be inserted.
And split_leaf return EOVERFLOW from following code:
if (extend && data_size + btrfs_item_size_nr(l, slot) +
sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(fs_info))
return -EOVERFLOW;
In most cases, when callers receive EOVERFLOW, they either return
this error or handle in different ways. For example, in normal dir item
creation the userspace will get errno EOVERFLOW; in inode ref case
INODE_EXTREF is used instead.
However, this is not the case for rename. To avoid the unrecoverable
situation in rename, btrfs_check_dir_item_collision is called in
early phase of rename. In this function, when item key collision is
detected leaf space is checked:
data_size = sizeof(*di) + name_len;
if (data_size + btrfs_item_size_nr(leaf, slot) +
sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root->fs_info))
the sizeof(struct btrfs_item) + btrfs_item_size_nr(leaf, slot) here
refers to existing item size, the condition here correctly calculates
the needed size for collision case rather than the wrong case above.
The consequence of inconsistent condition check between
btrfs_check_dir_item_collision and btrfs_search_slot when item key
collision happens is that we might pass check here but fail
later at btrfs_search_slot. Rename fails and volume is forced readonly
[436149.586170] ------------[ cut here ]------------
[436149.586173] BTRFS: Transaction aborted (error -75)
[436149.586196] WARNING: CPU: 0 PID: 16733 at fs/btrfs/inode.c:9870 btrfs_rename2+0x1938/0x1b70 [btrfs]
[436149.586227] CPU: 0 PID: 16733 Comm: python Tainted: G D 4.18.0-rc5+ #1
[436149.586228] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/05/2016
[436149.586238] RIP: 0010:btrfs_rename2+0x1938/0x1b70 [btrfs]
[436149.586254] RSP: 0018:ffffa327043a7ce0 EFLAGS: 00010286
[436149.586255] RAX: 0000000000000000 RBX: ffff8d8a17d13340 RCX: 0000000000000006
[436149.586256] RDX: 0000000000000007 RSI: 0000000000000096 RDI: ffff8d8a7fc164b0
[436149.586257] RBP: ffffa327043a7da0 R08: 0000000000000560 R09: 7265282064657472
[436149.586258] R10: 0000000000000000 R11: 6361736e61725420 R12: ffff8d8a0d4c8b08
[436149.586258] R13: ffff8d8a17d13340 R14: ffff8d8a33e0a540 R15: 00000000000001fe
[436149.586260] FS: 00007fa313933740(0000) GS:ffff8d8a7fc00000(0000) knlGS:0000000000000000
[436149.586261] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[436149.586262] CR2: 000055d8d9c9a720 CR3: 000000007aae0003 CR4: 00000000003606f0
[436149.586295] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[436149.586296] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[436149.586296] Call Trace:
[436149.586311] vfs_rename+0x383/0x920
[436149.586313] ? vfs_rename+0x383/0x920
[436149.586315] do_renameat2+0x4ca/0x590
[436149.586317] __x64_sys_rename+0x20/0x30
[436149.586324] do_syscall_64+0x5a/0x120
[436149.586330] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[436149.586332] RIP: 0033:0x7fa3133b1d37
[436149.586348] RSP: 002b:00007fffd3e43908 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
[436149.586349] RAX: ffffffffffffffda RBX: 00007fa3133b1d30 RCX: 00007fa3133b1d37
[436149.586350] RDX: 000055d8da06b5e0 RSI: 000055d8da225d60 RDI: 000055d8da2c4da0
[436149.586351] RBP: 000055d8da2252f0 R08: 00007fa313782000 R09: 00000000000177e0
[436149.586351] R10: 000055d8da010680 R11: 0000000000000246 R12: 00007fa313840b00
Thanks to Hans van Kranenburg for information about crc32 hash collision
tools, I was able to reproduce the dir item collision with following
python script.
https://github.com/wutzuchieh/misc_tools/blob/master/crc32_forge.py Run
it under a btrfs volume will trigger the abort transaction. It simply
creates files and rename them to forged names that leads to
hash collision.
There are two ways to fix this. One is to simply revert the patch
878f2d2cb3 ("Btrfs: fix max dir item size calculation") to make the
condition consistent although that patch is correct about the size.
The other way is to handle the leaf space check correctly when
collision happens. I prefer the second one since it correct leaf
space check in collision case. This fix will not account
sizeof(struct btrfs_item) when the item already exists.
There are two places where ins_len doesn't contain
sizeof(struct btrfs_item), however.
1. extent-tree.c: lookup_inline_extent_backref
2. file-item.c: btrfs_csum_file_blocks
to make the logic of btrfs_search_slot more clear, we add a flag
search_for_extension in btrfs_path.
This flag indicates that ins_len passed to btrfs_search_slot doesn't
contain sizeof(struct btrfs_item). When key exists, btrfs_search_slot
will use the actual size needed to calculate the required leaf space.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: ethanwu <ethanwu@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When cloning an inline extent there are cases where we can not just copy
the inline extent from the source range to the target range (e.g. when the
target range starts at an offset greater than zero). In such cases we copy
the inline extent's data into a page of the destination inode and then
dirty that page. However, after that we will need to start a transaction
for each processed extent and, if we are ever low on available metadata
space, we may need to flush existing delalloc for all dirty inodes in an
attempt to release metadata space - if that happens we may deadlock:
* the async reclaim task queued a delalloc work to flush delalloc for
the destination inode of the clone operation;
* the task executing that delalloc work gets blocked waiting for the
range with the dirty page to be unlocked, which is currently locked
by the task doing the clone operation;
* the async reclaim task blocks waiting for the delalloc work to complete;
* the cloning task is waiting on the waitqueue of its reservation ticket
while holding the range with the dirty page locked in the inode's
io_tree;
* if metadata space is not released by some other task (like delalloc for
some other inode completing for example), the clone task waits forever
and as a consequence the delalloc work and async reclaim tasks will hang
forever as well. Releasing more space on the other hand may require
starting a transaction, which will hang as well when trying to reserve
metadata space, resulting in a deadlock between all these tasks.
When this happens, traces like the following show up in dmesg/syslog:
[87452.323003] INFO: task kworker/u16:11:1810830 blocked for more than 120 seconds.
[87452.323644] Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
[87452.324248] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[87452.324852] task:kworker/u16:11 state:D stack: 0 pid:1810830 ppid: 2 flags:0x00004000
[87452.325520] Workqueue: btrfs-flush_delalloc btrfs_work_helper [btrfs]
[87452.326136] Call Trace:
[87452.326737] __schedule+0x5d1/0xcf0
[87452.327390] schedule+0x45/0xe0
[87452.328174] lock_extent_bits+0x1e6/0x2d0 [btrfs]
[87452.328894] ? finish_wait+0x90/0x90
[87452.329474] btrfs_invalidatepage+0x32c/0x390 [btrfs]
[87452.330133] ? __mod_memcg_state+0x8e/0x160
[87452.330738] __extent_writepage+0x2d4/0x400 [btrfs]
[87452.331405] extent_write_cache_pages+0x2b2/0x500 [btrfs]
[87452.332007] ? lock_release+0x20e/0x4c0
[87452.332557] ? trace_hardirqs_on+0x1b/0xf0
[87452.333127] extent_writepages+0x43/0x90 [btrfs]
[87452.333653] ? lock_acquire+0x1a3/0x490
[87452.334177] do_writepages+0x43/0xe0
[87452.334699] ? __filemap_fdatawrite_range+0xa4/0x100
[87452.335720] __filemap_fdatawrite_range+0xc5/0x100
[87452.336500] btrfs_run_delalloc_work+0x17/0x40 [btrfs]
[87452.337216] btrfs_work_helper+0xf1/0x600 [btrfs]
[87452.337838] process_one_work+0x24e/0x5e0
[87452.338437] worker_thread+0x50/0x3b0
[87452.339137] ? process_one_work+0x5e0/0x5e0
[87452.339884] kthread+0x153/0x170
[87452.340507] ? kthread_mod_delayed_work+0xc0/0xc0
[87452.341153] ret_from_fork+0x22/0x30
[87452.341806] INFO: task kworker/u16:1:2426217 blocked for more than 120 seconds.
[87452.342487] Tainted: G B W 5.10.0-rc4-btrfs-next-73 #1
[87452.343274] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[87452.344049] task:kworker/u16:1 state:D stack: 0 pid:2426217 ppid: 2 flags:0x00004000
[87452.344974] Workqueue: events_unbound btrfs_async_reclaim_metadata_space [btrfs]
[87452.345655] Call Trace:
[87452.346305] __schedule+0x5d1/0xcf0
[87452.346947] ? kvm_clock_read+0x14/0x30
[87452.347676] ? wait_for_completion+0x81/0x110
[87452.348389] schedule+0x45/0xe0
[87452.349077] schedule_timeout+0x30c/0x580
[87452.349718] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[87452.350340] ? lock_acquire+0x1a3/0x490
[87452.351006] ? try_to_wake_up+0x7a/0xa20
[87452.351541] ? lock_release+0x20e/0x4c0
[87452.352040] ? lock_acquired+0x199/0x490
[87452.352517] ? wait_for_completion+0x81/0x110
[87452.353000] wait_for_completion+0xab/0x110
[87452.353490] start_delalloc_inodes+0x2af/0x390 [btrfs]
[87452.353973] btrfs_start_delalloc_roots+0x12d/0x250 [btrfs]
[87452.354455] flush_space+0x24f/0x660 [btrfs]
[87452.355063] btrfs_async_reclaim_metadata_space+0x1bb/0x480 [btrfs]
[87452.355565] process_one_work+0x24e/0x5e0
[87452.356024] worker_thread+0x20f/0x3b0
[87452.356487] ? process_one_work+0x5e0/0x5e0
[87452.356973] kthread+0x153/0x170
[87452.357434] ? kthread_mod_delayed_work+0xc0/0xc0
[87452.357880] ret_from_fork+0x22/0x30
(...)
< stack traces of several tasks waiting for the locks of the inodes of the
clone operation >
(...)
[92867.444138] RSP: 002b:00007ffc3371bbe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
[92867.444624] RAX: ffffffffffffffda RBX: 00007ffc3371bea0 RCX: 00007f61efe73f97
[92867.445116] RDX: 0000000000000000 RSI: 0000560fbd5d7a40 RDI: 0000560fbd5d8960
[92867.445595] RBP: 00007ffc3371beb0 R08: 0000000000000001 R09: 0000000000000003
[92867.446070] R10: 00007ffc3371b996 R11: 0000000000000246 R12: 0000000000000000
[92867.446820] R13: 000000000000001f R14: 00007ffc3371bea0 R15: 00007ffc3371beb0
[92867.447361] task:fsstress state:D stack: 0 pid:2508238 ppid:2508153 flags:0x00004000
[92867.447920] Call Trace:
[92867.448435] __schedule+0x5d1/0xcf0
[92867.448934] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[92867.449423] schedule+0x45/0xe0
[92867.449916] __reserve_bytes+0x4a4/0xb10 [btrfs]
[92867.450576] ? finish_wait+0x90/0x90
[92867.451202] btrfs_reserve_metadata_bytes+0x29/0x190 [btrfs]
[92867.451815] btrfs_block_rsv_add+0x1f/0x50 [btrfs]
[92867.452412] start_transaction+0x2d1/0x760 [btrfs]
[92867.453216] clone_copy_inline_extent+0x333/0x490 [btrfs]
[92867.453848] ? lock_release+0x20e/0x4c0
[92867.454539] ? btrfs_search_slot+0x9a7/0xc30 [btrfs]
[92867.455218] btrfs_clone+0x569/0x7e0 [btrfs]
[92867.455952] btrfs_clone_files+0xf6/0x150 [btrfs]
[92867.456588] btrfs_remap_file_range+0x324/0x3d0 [btrfs]
[92867.457213] do_clone_file_range+0xd4/0x1f0
[92867.457828] vfs_clone_file_range+0x4d/0x230
[92867.458355] ? lock_release+0x20e/0x4c0
[92867.458890] ioctl_file_clone+0x8f/0xc0
[92867.459377] do_vfs_ioctl+0x342/0x750
[92867.459913] __x64_sys_ioctl+0x62/0xb0
[92867.460377] do_syscall_64+0x33/0x80
[92867.460842] entry_SYSCALL_64_after_hwframe+0x44/0xa9
(...)
< stack traces of more tasks blocked on metadata reservation like the clone
task above, because the async reclaim task has deadlocked >
(...)
Another thing to notice is that the worker task that is deadlocked when
trying to flush the destination inode of the clone operation is at
btrfs_invalidatepage(). This is simply because the clone operation has a
destination offset greater than the i_size and we only update the i_size
of the destination file after cloning an extent (just like we do in the
buffered write path).
Since the async reclaim path uses btrfs_start_delalloc_roots() to trigger
the flushing of delalloc for all inodes that have delalloc, add a runtime
flag to an inode to signal it should not be flushed, and for inodes with
that flag set, start_delalloc_inodes() will simply skip them. When the
cloning code needs to dirty a page to copy an inline extent, set that flag
on the inode and then clear it when the clone operation finishes.
This could be sporadically triggered with test case generic/269 from
fstests, which exercises many fsstress processes running in parallel with
several dd processes filling up the entire filesystem.
CC: stable@vger.kernel.org # 5.9+
Fixes: 05a5a7621c ("Btrfs: implement full reflink support for inline extents")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-5.11-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"We have a mix of all kinds of changes, feature updates, core stuff,
performance improvements and lots of cleanups and preparatory changes.
User visible:
- export filesystem generation in sysfs
- new features for mount option 'rescue':
- what's currently supported is exported in sysfs
- 'ignorebadroots'/'ibadroots' - continue even if some essential
tree roots are not usable (extent, uuid, data reloc, device,
csum, free space)
- 'ignoredatacsums'/'idatacsums' - skip checksum verification on
data
- 'all' - now enables 'ignorebadroots' + 'ignoredatacsums' +
'nologreplay'
- export read mirror policy settings to sysfs, new policies will be
added in the future
- remove inode number cache feature (mount -o inode_cache), obsoleted
in 5.9
User visible fixes:
- async discard scheduling fixes on high loads
- update inode byte counter atomically so stat() does not report
wrong value in some cases
- free space tree fixes:
- correctly report status of v2 after remount
- clear v1 cache inodes when v2 is newly enabled after remount
Core:
- switch own tree lock implementation to standard rw semaphore:
- one-level lock nesting is not required anymore, the last use of
this was in free space that's now loaded asynchronously
- own implementation of adaptive spinning before taking mutex has
been part of rwsem
- performance seems to be better in general, much better (+tens
of percents) for some workloads
- lockdep does not complain
- finish direct IO conversion to iomap infrastructure, remove
temporary workaround for DSYNC after iomap API updates
- preparatory work to support data and metadata blocks smaller than
page:
- generalize code that assumes sectorsize == PAGE_SIZE, lots of
refactoring
- planned namely for 64K pages (eg. arm64, ppc64)
- scrub read-only support
- preparatory work for zoned allocation mode (SMR/ZBC/ZNS friendly):
- disable incompatible features
- round-robin superblock write
- free space cache (v1) is loaded asynchronously, remove tree path
recursion
- slightly improved time tacking for transaction kthread wake ups
Performance improvements (note that the numbers depend on load type or
other features and weren't run on the same machine):
- skip unnecessary work:
- do not start readahead for csum tree when scrubbing non-data
block groups
- do not start and wait for delalloc on snapshot roots on
transaction commit
- fix race when defragmenting leads to unnecessary IO
- dbench speedups (+throughput%/-max latency%):
- skip unnecessary searches for xattrs when logging an inode
(+10.8/-8.2)
- stop incrementing log batch when joining log transaction (1-2)
- unlock path before checking if extent is shared during nocow
writeback (+5.0/-20.5), on fio load +9.7% throughput/-9.8%
runtime
- several tree log improvements, eg. removing unnecessary
operations, fixing races that lead to additional work
(+12.7/-8.2)
- tree-checker error branches annotated with unlikely() (+3%
throughput)
Other:
- cleanups
- lockdep fixes
- more btrfs_inode conversions
- error variable cleanups"
* tag 'for-5.11-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (198 commits)
btrfs: scrub: allow scrub to work with subpage sectorsize
btrfs: scrub: support subpage data scrub
btrfs: scrub: support subpage tree block scrub
btrfs: scrub: always allocate one full page for one sector for RAID56
btrfs: scrub: reduce width of extent_len/stripe_len from 64 to 32 bits
btrfs: refactor btrfs_lookup_bio_sums to handle out-of-order bvecs
btrfs: remove btrfs_find_ordered_sum call from btrfs_lookup_bio_sums
btrfs: handle sectorsize < PAGE_SIZE case for extent buffer accessors
btrfs: update num_extent_pages to support subpage sized extent buffer
btrfs: don't allow tree block to cross page boundary for subpage support
btrfs: calculate inline extent buffer page size based on page size
btrfs: factor out btree page submission code to a helper
btrfs: make btrfs_verify_data_csum follow sector size
btrfs: pass bio_offset to check_data_csum() directly
btrfs: rename bio_offset of extent_submit_bio_start_t to dio_file_offset
btrfs: fix lockdep warning when creating free space tree
btrfs: skip space_cache v1 setup when not using it
btrfs: remove free space items when disabling space cache v1
btrfs: warn when remount will not change the free space tree
btrfs: use superblock state to print space_cache mount option
...
- Consolidate all kmap_atomic() internals into a generic implementation
which builds the base for the kmap_local() API and make the
kmap_atomic() interface wrappers which handle the disabling/enabling of
preemption and pagefaults.
- Switch the storage from per-CPU to per task and provide scheduler
support for clearing mapping when scheduling out and restoring them
when scheduling back in.
- Merge the migrate_disable/enable() code, which is also part of the
scheduler pull request. This was required to make the kmap_local()
interface available which does not disable preemption when a mapping
is established. It has to disable migration instead to guarantee that
the virtual address of the mapped slot is the same accross preemption.
- Provide better debug facilities: guard pages and enforced utilization
of the mapping mechanics on 64bit systems when the architecture allows
it.
- Provide the new kmap_local() API which can now be used to cleanup the
kmap_atomic() usage sites all over the place. Most of the usage sites
do not require the implicit disabling of preemption and pagefaults so
the penalty on 64bit and 32bit non-highmem systems is removed and quite
some of the code can be simplified. A wholesale conversion is not
possible because some usage depends on the implicit side effects and
some need to be cleaned up because they work around these side effects.
The migrate disable side effect is only effective on highmem systems
and when enforced debugging is enabled. On 64bit and 32bit non-highmem
systems the overhead is completely avoided.
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Merge tag 'core-mm-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull kmap updates from Thomas Gleixner:
"The new preemtible kmap_local() implementation:
- Consolidate all kmap_atomic() internals into a generic
implementation which builds the base for the kmap_local() API and
make the kmap_atomic() interface wrappers which handle the
disabling/enabling of preemption and pagefaults.
- Switch the storage from per-CPU to per task and provide scheduler
support for clearing mapping when scheduling out and restoring them
when scheduling back in.
- Merge the migrate_disable/enable() code, which is also part of the
scheduler pull request. This was required to make the kmap_local()
interface available which does not disable preemption when a
mapping is established. It has to disable migration instead to
guarantee that the virtual address of the mapped slot is the same
across preemption.
- Provide better debug facilities: guard pages and enforced
utilization of the mapping mechanics on 64bit systems when the
architecture allows it.
- Provide the new kmap_local() API which can now be used to cleanup
the kmap_atomic() usage sites all over the place. Most of the usage
sites do not require the implicit disabling of preemption and
pagefaults so the penalty on 64bit and 32bit non-highmem systems is
removed and quite some of the code can be simplified. A wholesale
conversion is not possible because some usage depends on the
implicit side effects and some need to be cleaned up because they
work around these side effects.
The migrate disable side effect is only effective on highmem
systems and when enforced debugging is enabled. On 64bit and 32bit
non-highmem systems the overhead is completely avoided"
* tag 'core-mm-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
ARM: highmem: Fix cache_is_vivt() reference
x86/crashdump/32: Simplify copy_oldmem_page()
io-mapping: Provide iomap_local variant
mm/highmem: Provide kmap_local*
sched: highmem: Store local kmaps in task struct
x86: Support kmap_local() forced debugging
mm/highmem: Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
mm/highmem: Provide and use CONFIG_DEBUG_KMAP_LOCAL
microblaze/mm/highmem: Add dropped #ifdef back
xtensa/mm/highmem: Make generic kmap_atomic() work correctly
mm/highmem: Take kmap_high_get() properly into account
highmem: High implementation details and document API
Documentation/io-mapping: Remove outdated blurb
io-mapping: Cleanup atomic iomap
mm/highmem: Remove the old kmap_atomic cruft
highmem: Get rid of kmap_types.h
xtensa/mm/highmem: Switch to generic kmap atomic
sparc/mm/highmem: Switch to generic kmap atomic
powerpc/mm/highmem: Switch to generic kmap atomic
nds32/mm/highmem: Switch to generic kmap atomic
...
Refactor btrfs_lookup_bio_sums() by:
- Remove the @file_offset parameter
There are two factors making the @file_offset parameter useless:
* For csum lookup in csum tree, file offset makes no sense
We only need disk_bytenr, which is unrelated to file_offset
* page_offset (file offset) of each bvec is not contiguous.
Pages can be added to the same bio as long as their on-disk bytenr
is contiguous, meaning we could have pages at different file offsets
in the same bio.
Thus passing file_offset makes no sense any more.
The only user of file_offset is for data reloc inode, we will use
a new function, search_file_offset_in_bio(), to handle it.
- Extract the csum tree lookup into search_csum_tree()
The new function will handle the csum search in csum tree.
The return value is the same as btrfs_find_ordered_sum(), returning
the number of found sectors which have checksum.
- Change how we do the main loop
The only needed info from bio is:
* the on-disk bytenr
* the length
After extracting the above info, we can do the search without bio
at all, which makes the main loop much simpler:
for (cur_disk_bytenr = orig_disk_bytenr;
cur_disk_bytenr < orig_disk_bytenr + orig_len;
cur_disk_bytenr += count * sectorsize) {
/* Lookup csum tree */
count = search_csum_tree(fs_info, path, cur_disk_bytenr,
search_len, csum_dst);
if (!count) {
/* Csum hole handling */
}
}
- Use single variable as the source to calculate all other offsets
Instead of all different type of variables, we use only one main
variable, cur_disk_bytenr, which represents the current disk bytenr.
All involved values can be calculated from that variable, and
all those variable will only be visible in the inner loop.
The above refactoring makes btrfs_lookup_bio_sums() way more robust than
it used to be, especially related to the file offset lookup. Now
file_offset lookup is only related to data reloc inode, otherwise we
don't need to bother file_offset at all.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
To support sectorsize < PAGE_SIZE case, we need to take extra care of
extent buffer accessors.
Since sectorsize is smaller than PAGE_SIZE, one page can contain
multiple tree blocks, we must use eb->start to determine the real offset
to read/write for extent buffer accessors.
This patch introduces two helpers to do this:
- get_eb_page_index()
This is to calculate the index to access extent_buffer::pages.
It's just a simple wrapper around "start >> PAGE_SHIFT".
For sectorsize == PAGE_SIZE case, nothing is changed.
For sectorsize < PAGE_SIZE case, we always get index as 0, and
the existing page shift also works.
- get_eb_offset_in_page()
This is to calculate the offset to access extent_buffer::pages.
This needs to take extent_buffer::start into consideration.
For sectorsize == PAGE_SIZE case, extent_buffer::start is always
aligned to PAGE_SIZE, thus adding extent_buffer::start to
offset_in_page() won't change the result.
For sectorsize < PAGE_SIZE case, adding extent_buffer::start gives
us the correct offset to access.
This patch will touch the following parts to cover all extent buffer
accessors:
- BTRFS_SETGET_HEADER_FUNCS()
- read_extent_buffer()
- read_extent_buffer_to_user()
- memcmp_extent_buffer()
- write_extent_buffer_chunk_tree_uuid()
- write_extent_buffer_fsid()
- write_extent_buffer()
- memzero_extent_buffer()
- copy_extent_buffer_full()
- copy_extent_buffer()
- memcpy_extent_buffer()
- memmove_extent_buffer()
- btrfs_get_token_##bits()
- btrfs_get_##bits()
- btrfs_set_token_##bits()
- btrfs_set_##bits()
- generic_bin_search()
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs only support 64K as maximum node size, thus for 4K page system, we
would have at most 16 pages for one extent buffer.
For a system using 64K page size, we would really have just one page.
While we always use 16 pages for extent_buffer::pages, this means for
systems using 64K pages, we are wasting memory for 15 page pointers
which will never be used.
Calculate the array size based on page size and the node size maximum.
- for systems using 4K page size, it will stay 16 pages
- for systems using 64K page size, it will be 1 page
Move the definition of BTRFS_MAX_METADATA_BLOCKSIZE to btrfs_tree.h, to
avoid circular inclusion of ctree.h.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Parameter icsum for check_data_csum() is a little hard to understand.
So is the phy_offset for btrfs_verify_data_csum().
Both parameters are calculated values for csum lookup.
Instead of some calculated value, just pass bio_offset and let the
final and only user, check_data_csum(), calculate whatever it needs.
Since we are here, also make the bio_offset parameter and some related
variables to be u32 (unsigned int).
As bio size is limited by its bi_size, which is unsigned int, and has
extra size limit check during various bio operations.
Thus we are ensured that bio_offset won't overflow u32.
Thus for all involved functions, not only rename the parameter from
@phy_offset to @bio_offset, but also reduce its width to u32, so we
won't have suspicious "u32 = u64 >> sector_bits;" lines anymore.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When mounting, btrfs uses the cache_generation in the super block to
determine if space cache v1 is in use. However, by mounting with
nospace_cache or space_cache=v2, it is possible to disable space cache
v1, which does not result in un-setting cache_generation back to 0.
In order to base some logic, like mount option printing in /proc/mounts,
on the current state of the space cache rather than just the values of
the mount option, keep the value of cache_generation consistent with the
status of space cache v1.
We ensure that cache_generation > 0 iff the file system is using
space_cache v1. This requires committing a transaction on any mount
which changes whether we are using v1. (v1->nospace_cache, v1->v2,
nospace_cache->v1, v2->v1).
Since the mechanism for writing out the cache generation is transaction
commit, but we want some finer grained control over when we un-set it,
we can't just rely on the SPACE_CACHE mount option, and introduce an
fs_info flag that mount can use when it wants to unset the generation.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Early on during a transaction commit we acquire the tree_log_mutex and
hold it until after we write the super blocks. But before writing the
extent buffers dirtied by the transaction and the super blocks we unblock
the transaction by setting its state to TRANS_STATE_UNBLOCKED and setting
fs_info->running_transaction to NULL.
This means that after that and before writing the super blocks, new
transactions can start. However if any transaction wants to log an inode,
it will block waiting for the transaction commit to write its dirty
extent buffers and the super blocks because the tree_log_mutex is only
released after those operations are complete, and starting a new log
transaction blocks on that mutex (at start_log_trans()).
Writing the dirty extent buffers and the super blocks can take a very
significant amount of time to complete, but we could allow the tasks
wanting to log an inode to proceed with most of their steps:
1) create the log trees
2) log metadata in the trees
3) write their dirty extent buffers
They only need to wait for the previous transaction commit to complete
(write its super blocks) before they attempt to write their super blocks,
otherwise we could end up with a corrupt filesystem after a crash.
So change start_log_trans() to use the root tree's log_mutex to serialize
for the creation of the log root tree instead of using the tree_log_mutex,
and make btrfs_sync_log() acquire the tree_log_mutex before writing the
super blocks. This allows for inode logging to wait much less time when
there is a previous transaction that is still committing, often not having
to wait at all, as by the time when we try to sync the log the previous
transaction already wrote its super blocks.
This patch belongs to a patch set that is comprised of the following
patches:
btrfs: fix race causing unnecessary inode logging during link and rename
btrfs: fix race that results in logging old extents during a fast fsync
btrfs: fix race that causes unnecessary logging of ancestor inodes
btrfs: fix race that makes inode logging fallback to transaction commit
btrfs: fix race leading to unnecessary transaction commit when logging inode
btrfs: do not block inode logging for so long during transaction commit
The following script that uses dbench was used to measure the impact of
the whole patchset:
$ cat test-dbench.sh
#!/bin/bash
DEV=/dev/nvme0n1
MNT=/mnt/btrfs
MOUNT_OPTIONS="-o ssd"
echo "performance" | \
tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
mkfs.btrfs -f -m single -d single $DEV
mount $MOUNT_OPTIONS $DEV $MNT
dbench -D $MNT -t 300 64
umount $MNT
The test was run on a machine with 12 cores, 64G of ram, using a NVMe
device and a non-debug kernel configuration (Debian's default).
Before patch set:
Operation Count AvgLat MaxLat
----------------------------------------
NTCreateX 11277211 0.250 85.340
Close 8283172 0.002 6.479
Rename 477515 1.935 86.026
Unlink 2277936 0.770 87.071
Deltree 256 15.732 81.379
Mkdir 128 0.003 0.009
Qpathinfo 10221180 0.056 44.404
Qfileinfo 1789967 0.002 4.066
Qfsinfo 1874399 0.003 9.176
Sfileinfo 918589 0.061 10.247
Find 3951758 0.341 54.040
WriteX 5616547 0.047 85.079
ReadX 17676028 0.005 9.704
LockX 36704 0.003 1.800
UnlockX 36704 0.002 0.687
Flush 790541 14.115 676.236
Throughput 1179.19 MB/sec 64 clients 64 procs max_latency=676.240 ms
After patch set:
Operation Count AvgLat MaxLat
----------------------------------------
NTCreateX 12687926 0.171 86.526
Close 9320780 0.002 8.063
Rename 537253 1.444 78.576
Unlink 2561827 0.559 87.228
Deltree 374 11.499 73.549
Mkdir 187 0.003 0.005
Qpathinfo 11500300 0.061 36.801
Qfileinfo 2017118 0.002 7.189
Qfsinfo 2108641 0.003 4.825
Sfileinfo 1033574 0.008 8.065
Find 4446553 0.408 47.835
WriteX 6335667 0.045 84.388
ReadX 19887312 0.003 9.215
LockX 41312 0.003 1.394
UnlockX 41312 0.002 1.425
Flush 889233 13.014 623.259
Throughput 1339.32 MB/sec 64 clients 64 procs max_latency=623.265 ms
+12.7% throughput, -8.2% max latency
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's been deprecated since commit b547a88ea5 ("btrfs: start
deprecation of mount option inode_cache") which enumerates the reasons.
A filesystem that uses the feature (mount -o inode_cache) tracks the
inode numbers in bitmaps, that data stay on the filesystem after this
patch. The size is roughly 5MiB for 1M inodes [1], which is considered
small enough to be left there. Removal of the change can be implemented
in btrfs-progs if needed.
[1] https://lore.kernel.org/linux-btrfs/20201127145836.GZ6430@twin.jikos.cz/
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
The zone append write command has a maximum IO size restriction it
accepts. This is because a zone append write command cannot be split, as
we ask the device to place the data into a specific target zone and the
device responds with the actual written location of the data.
Introduce max_zone_append_size to zone_info and fs_info to track the
value, so we can limit all I/O to a zoned block device that we want to
write using the zone append command to the device's limits.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Introduce function btrfs_check_zoned_mode() to check if ZONED flag is
enabled on the file system and if the file system consists of zoned
devices with equal zone size.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With my async free space cache loading patches ("btrfs: load free space
cache asynchronously") we no longer have a user of path->recurse and can
remove it.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are several occasions where we do not update the inode's number of
used bytes atomically, resulting in a concurrent stat(2) syscall to report
a value of used blocks that does not correspond to a valid value, that is,
a value that does not match neither what we had before the operation nor
what we get after the operation completes.
In extreme cases it can result in stat(2) reporting zero used blocks, which
can cause problems for some userspace tools where they can consider a file
with a non-zero size and zero used blocks as completely sparse and skip
reading data, as reported/discussed a long time ago in some threads like
the following:
https://lists.gnu.org/archive/html/bug-tar/2016-07/msg00001.html
The cases where this can happen are the following:
-> Case 1
If we do a write (buffered or direct IO) against a file region for which
there is already an allocated extent (or multiple extents), then we have a
short time window where we can report a number of used blocks to stat(2)
that does not take into account the file region being overwritten. This
short time window happens when completing the ordered extent(s).
This happens because when we drop the extents in the write range we
decrement the inode's number of bytes and later on when we insert the new
extent(s) we increment the number of bytes in the inode, resulting in a
short time window where a stat(2) syscall can get an incorrect number of
used blocks.
If we do writes that overwrite an entire file, then we have a short time
window where we report 0 used blocks to stat(2).
Example reproducer:
$ cat reproducer-1.sh
#!/bin/bash
MNT=/mnt/sdi
DEV=/dev/sdi
stat_loop()
{
trap "wait; exit" SIGTERM
local filepath=$1
local expected=$2
local got
while :; do
got=$(stat -c %b $filepath)
if [ $got -ne $expected ]; then
echo -n "ERROR: unexpected used blocks"
echo " (got: $got expected: $expected)"
fi
done
}
mkfs.btrfs -f $DEV > /dev/null
# mkfs.xfs -f $DEV > /dev/null
# mkfs.ext4 -F $DEV > /dev/null
# mkfs.f2fs -f $DEV > /dev/null
# mkfs.reiserfs -f $DEV > /dev/null
mount $DEV $MNT
xfs_io -f -s -c "pwrite -b 64K 0 64K" $MNT/foobar >/dev/null
expected=$(stat -c %b $MNT/foobar)
# Create a process to keep calling stat(2) on the file and see if the
# reported number of blocks used (disk space used) changes, it should
# not because we are not increasing the file size nor punching holes.
stat_loop $MNT/foobar $expected &
loop_pid=$!
for ((i = 0; i < 50000; i++)); do
xfs_io -s -c "pwrite -b 64K 0 64K" $MNT/foobar >/dev/null
done
kill $loop_pid &> /dev/null
wait
umount $DEV
$ ./reproducer-1.sh
ERROR: unexpected used blocks (got: 0 expected: 128)
ERROR: unexpected used blocks (got: 0 expected: 128)
(...)
Note that since this is a short time window where the race can happen, the
reproducer may not be able to always trigger the bug in one run, or it may
trigger it multiple times.
-> Case 2
If we do a buffered write against a file region that does not have any
allocated extents, like a hole or beyond EOF, then during ordered extent
completion we have a short time window where a concurrent stat(2) syscall
can report a number of used blocks that does not correspond to the value
before or after the write operation, a value that is actually larger than
the value after the write completes.
This happens because once we start a buffered write into an unallocated
file range we increment the inode's 'new_delalloc_bytes', to make sure
any stat(2) call gets a correct used blocks value before delalloc is
flushed and completes. However at ordered extent completion, after we
inserted the new extent, we increment the inode's number of bytes used
with the size of the new extent, and only later, when clearing the range
in the inode's iotree, we decrement the inode's 'new_delalloc_bytes'
counter with the size of the extent. So this results in a short time
window where a concurrent stat(2) syscall can report a number of used
blocks that accounts for the new extent twice.
Example reproducer:
$ cat reproducer-2.sh
#!/bin/bash
MNT=/mnt/sdi
DEV=/dev/sdi
stat_loop()
{
trap "wait; exit" SIGTERM
local filepath=$1
local expected=$2
local got
while :; do
got=$(stat -c %b $filepath)
if [ $got -ne $expected ]; then
echo -n "ERROR: unexpected used blocks"
echo " (got: $got expected: $expected)"
fi
done
}
mkfs.btrfs -f $DEV > /dev/null
# mkfs.xfs -f $DEV > /dev/null
# mkfs.ext4 -F $DEV > /dev/null
# mkfs.f2fs -f $DEV > /dev/null
# mkfs.reiserfs -f $DEV > /dev/null
mount $DEV $MNT
touch $MNT/foobar
write_size=$((64 * 1024))
for ((i = 0; i < 16384; i++)); do
offset=$(($i * $write_size))
xfs_io -c "pwrite -S 0xab $offset $write_size" $MNT/foobar >/dev/null
blocks_used=$(stat -c %b $MNT/foobar)
# Fsync the file to trigger writeback and keep calling stat(2) on it
# to see if the number of blocks used changes.
stat_loop $MNT/foobar $blocks_used &
loop_pid=$!
xfs_io -c "fsync" $MNT/foobar
kill $loop_pid &> /dev/null
wait $loop_pid
done
umount $DEV
$ ./reproducer-2.sh
ERROR: unexpected used blocks (got: 265472 expected: 265344)
ERROR: unexpected used blocks (got: 284032 expected: 283904)
(...)
Note that since this is a short time window where the race can happen, the
reproducer may not be able to always trigger the bug in one run, or it may
trigger it multiple times.
-> Case 3
Another case where such problems happen is during other operations that
replace extents in a file range with other extents. Those operations are
extent cloning, deduplication and fallocate's zero range operation.
The cause of the problem is similar to the first case. When we drop the
extents from a range, we decrement the inode's number of bytes, and later
on, after inserting the new extents we increment it. Since this is not
done atomically, a concurrent stat(2) call can see and return a number of
used blocks that is smaller than it should be, does not match the number
of used blocks before or after the clone/deduplication/zero operation.
Like for the first case, when doing a clone, deduplication or zero range
operation against an entire file, we end up having a time window where we
can report 0 used blocks to a stat(2) call.
Example reproducer:
$ cat reproducer-3.sh
#!/bin/bash
MNT=/mnt/sdi
DEV=/dev/sdi
mkfs.btrfs -f $DEV > /dev/null
# mkfs.xfs -f -m reflink=1 $DEV > /dev/null
mount $DEV $MNT
extent_size=$((64 * 1024))
num_extents=16384
file_size=$(($extent_size * $num_extents))
# File foo has many small extents.
xfs_io -f -s -c "pwrite -S 0xab -b $extent_size 0 $file_size" $MNT/foo \
> /dev/null
# File bar has much less extents and has exactly the same data as foo.
xfs_io -f -c "pwrite -S 0xab 0 $file_size" $MNT/bar > /dev/null
expected=$(stat -c %b $MNT/foo)
# Now deduplicate bar into foo. While the deduplication is in progres,
# the number of used blocks/file size reported by stat should not change
xfs_io -c "dedupe $MNT/bar 0 0 $file_size" $MNT/foo > /dev/null &
dedupe_pid=$!
while [ -n "$(ps -p $dedupe_pid -o pid=)" ]; do
used=$(stat -c %b $MNT/foo)
if [ $used -ne $expected ]; then
echo "Unexpected blocks used: $used (expected: $expected)"
fi
done
umount $DEV
$ ./reproducer-3.sh
Unexpected blocks used: 2076800 (expected: 2097152)
Unexpected blocks used: 2097024 (expected: 2097152)
Unexpected blocks used: 2079872 (expected: 2097152)
(...)
Note that since this is a short time window where the race can happen, the
reproducer may not be able to always trigger the bug in one run, or it may
trigger it multiple times.
So fix this by:
1) Making btrfs_drop_extents() not decrement the VFS inode's number of
bytes, and instead return the number of bytes;
2) Making any code that drops extents and adds new extents update the
inode's number of bytes atomically, while holding the btrfs inode's
spinlock, which is also used by the stat(2) callback to get the inode's
number of bytes;
3) For ranges in the inode's iotree that are marked as 'delalloc new',
corresponding to previously unallocated ranges, increment the inode's
number of bytes when clearing the 'delalloc new' bit from the range,
in the same critical section that decrements the inode's
'new_delalloc_bytes' counter, delimited by the btrfs inode's spinlock.
An alternative would be to have btrfs_getattr() wait for any IO (ordered
extents in progress) and locking the whole range (0 to (u64)-1) while it
it computes the number of blocks used. But that would mean blocking
stat(2), which is a very used syscall and expected to be fast, waiting
for writes, clone/dedupe, fallocate, page reads, fiemap, etc.
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are many arguments for __btrfs_drop_extents() and its wrapper
btrfs_drop_extents(), which makes it hard to add more arguments to it and
requires changing every caller. I have added a couple myself back in 2014
commit 1acae57b16 ("Btrfs: faster file extent item replace operations")
and therefore know firsthand that it is a bit cumbersome to add additional
arguments to these functions.
Since I will need to add more arguments in a subsequent bug fix, this
change is preparatory work and adds a data structure that holds all the
arguments, for both input and output, that are passed to this function,
with some comments in the structure's definition mentioning what each
field is and how it relates to other fields.
Callers of this function need only to zero out the content of the
structure and setup only the fields they need. This also removes the
need to have both __btrfs_drop_extents() and btrfs_drop_extents(), so
now we have a single function named btrfs_drop_extents() that takes a
pointer to this new data structure (struct btrfs_drop_extents_args).
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If btrfs_discard_schedule_work() is called with override=true, it sets
delay anew regardless how much time is left until the timer should have
fired. If delays are long (that can happen, for example, with low
kbps_limit), they might get constantly overridden without having a
chance to run the discard work.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Most delay calculations are done in ns or ms, so store
discard_ctl->delay in ms and convert the final delay to jiffies only at
the end.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For subpage sector size support, one page can contain multiple tree
blocks. The entries cannot be based on page size and index must be
derived from the sectorsize. No change for page size == sector size.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
While writing an explanation for the need of the commit_root_sem for
btrfs_prepare_extent_commit, I realized we have a slight hole that could
result in leaked space if we have to do the old style caching. Consider
the following scenario
commit root
+----+----+----+----+----+----+----+
|\\\\| |\\\\|\\\\| |\\\\|\\\\|
+----+----+----+----+----+----+----+
0 1 2 3 4 5 6 7
new commit root
+----+----+----+----+----+----+----+
| | | |\\\\| | |\\\\|
+----+----+----+----+----+----+----+
0 1 2 3 4 5 6 7
Prior to this patch, we run btrfs_prepare_extent_commit, which updates
the last_byte_to_unpin, and then we subsequently run
switch_commit_roots. In this example lets assume that
caching_ctl->progress == 1 at btrfs_prepare_extent_commit() time, which
means that cache->last_byte_to_unpin == 1. Then we go and do the
switch_commit_roots(), but in the meantime the caching thread has made
some more progress, because we drop the commit_root_sem and re-acquired
it. Now caching_ctl->progress == 3. We swap out the commit root and
carry on to unpin.
The race can happen like:
1) The caching thread was running using the old commit root when it
found the extent for [2, 3);
2) Then it released the commit_root_sem because it was in the last
item of a leaf and the semaphore was contended, and set ->progress
to 3 (value of 'last'), as the last extent item in the current leaf
was for the extent for range [2, 3);
3) Next time it gets the commit_root_sem, will start using the new
commit root and search for a key with offset 3, so it never finds
the hole for [2, 3).
So the caching thread never saw [2, 3) as free space in any of the
commit roots, and by the time finish_extent_commit() was called for
the range [0, 3), ->last_byte_to_unpin was 1, so it only returned the
subrange [0, 1) to the free space cache, skipping [2, 3).
In the unpin code we have last_byte_to_unpin == 1, so we unpin [0,1),
but do not unpin [2,3). However because caching_ctl->progress == 3 we
do not see the newly freed section of [2,3), and thus do not add it to
our free space cache. This results in us missing a chunk of free space
in memory (on disk too, unless we have a power failure before writing
the free space cache to disk).
Fix this by making sure the ->last_byte_to_unpin is set at the same time
that we swap the commit roots, this ensures that we will always be
consistent.
CC: stable@vger.kernel.org # 5.8+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
[ update changelog with Filipe's review comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
We no longer distinguish between blocking and spinning, so rip out all
this code.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_csum_bytes_to_leaves shows up in system profiles, which makes it a
candidate for optimizations. After the 64bit division has been replaced
by shift, there's still a calculation done each time the function is
called: checksums per leaf.
As this is a constant value for the entire filesystem lifetime, we
can calculate it once at mount time and reuse. This also allows to
reduce the division to 64bit/32bit as we know the constant will always
fit the 32bit type.
Replace the open-coded rounding up with a macro that internally handles
the 64bit division and as it's now a short function, make it static
inline (slight code increase, slight stack usage reduction).
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In many places we need the checksum size and it is inefficient to read
it from the raw superblock. Store the value into fs_info, actual use
will be in followup patches. The size is u32 as it allows to generate
better assembly than with u16.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value of super_block::s_blocksize_bits is the same as
fs_info::sectorsize_bits, but we don't need to do the extra dereferences
in many functions and storing the bits as u32 (in fs_info) generates
shorter assembly.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We do a lot of calculations where we divide or multiply by sectorsize.
We also know and make sure that sectorsize is a power of two, so this
means all divisions can be turned to shifts and avoid eg. expensive
u64/u32 divisions.
The type is u32 as it's more register friendly on x86_64 compared to u8
and the resulting assembly is smaller (movzbl vs movl).
There's also superblock s_blocksize_bits but it's usually one more
pointer dereference farther than fs_info.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The drop_level member is used directly unlike all the other int types in
root_item. Add the definition and use it everywhere. The type is u8 so
there's no conversion necessary and the helpers are properly inlined,
this is for consistency.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This effectively reverts 09745ff88d93 ("btrfs: dio iomap DSYNC
workaround") now that the iomap API has been updated to allow
iomap_dio_complete() not to be called under i_rwsem anymore.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_inode_lock/unlock() are wrappers around inode locks, separating
the type of lock and actual locking.
- 0 - default, exclusive lock
- BTRFS_ILOCK_SHARED - for shared locks, for possible parallel DIO
- BTRFS_ILOCK_TRY - for the RWF_NOWAIT sequence
The bits SHARED and TRY can be combined together.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The read and write DIO don't have anything in common except for the
call to iomap_dio_rw. Extract the write call into a new function to get
rid of conditional statements for direct write.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
There are cases where you can end up with bad data csums because of
misbehaving applications. This happens when an application modifies a
buffer in-flight when doing an O_DIRECT write. In order to recover the
file we need a way to turn off data checksums so you can copy the file
off, and then you can delete the file and restore it properly later.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the face of extent root corruption, or any other core fs wide root
corruption we will fail to mount the file system. This makes recovery
kind of a pain, because you need to fall back to userspace tools to
scrape off data. Instead provide a mechanism to gracefully handle bad
roots, so we can at least mount read-only and possibly recover data from
the file system.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Set the extent bits EXTENT_NORESERVE inside btrfs_dirty_pages() as
opposed to calling set_extent_bits again later.
Fold check for written length within the function.
Note: EXTENT_NORESERVE is set before unlocking extents.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Historical leftovers from the time where kmap() had fixed slots.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Sterba <dsterba@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20201103095856.870272797@linutronix.de
Very sporadically I had test case btrfs/069 from fstests hanging (for
years, it is not a recent regression), with the following traces in
dmesg/syslog:
[162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started
[162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0
[162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished
[162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds.
[162513.514318] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.514747] task:btrfs-transacti state:D stack: 0 pid:1356167 ppid: 2 flags:0x00004000
[162513.514751] Call Trace:
[162513.514761] __schedule+0x5ce/0xd00
[162513.514765] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.514771] schedule+0x46/0xf0
[162513.514844] wait_current_trans+0xde/0x140 [btrfs]
[162513.514850] ? finish_wait+0x90/0x90
[162513.514864] start_transaction+0x37c/0x5f0 [btrfs]
[162513.514879] transaction_kthread+0xa4/0x170 [btrfs]
[162513.514891] ? btrfs_cleanup_transaction+0x660/0x660 [btrfs]
[162513.514894] kthread+0x153/0x170
[162513.514897] ? kthread_stop+0x2c0/0x2c0
[162513.514902] ret_from_fork+0x22/0x30
[162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds.
[162513.515192] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.515680] task:fsstress state:D stack: 0 pid:1356184 ppid:1356177 flags:0x00004000
[162513.515682] Call Trace:
[162513.515688] __schedule+0x5ce/0xd00
[162513.515691] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.515697] schedule+0x46/0xf0
[162513.515712] wait_current_trans+0xde/0x140 [btrfs]
[162513.515716] ? finish_wait+0x90/0x90
[162513.515729] start_transaction+0x37c/0x5f0 [btrfs]
[162513.515743] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
[162513.515753] btrfs_sync_fs+0x61/0x1c0 [btrfs]
[162513.515758] ? __ia32_sys_fdatasync+0x20/0x20
[162513.515761] iterate_supers+0x87/0xf0
[162513.515765] ksys_sync+0x60/0xb0
[162513.515768] __do_sys_sync+0xa/0x10
[162513.515771] do_syscall_64+0x33/0x80
[162513.515774] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.515781] RIP: 0033:0x7f5238f50bd7
[162513.515782] Code: Bad RIP value.
[162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
[162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
[162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a
[162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0
[162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a
[162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
[162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds.
[162513.516064] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.516617] task:fsstress state:D stack: 0 pid:1356185 ppid:1356177 flags:0x00000000
[162513.516620] Call Trace:
[162513.516625] __schedule+0x5ce/0xd00
[162513.516628] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.516634] schedule+0x46/0xf0
[162513.516647] wait_current_trans+0xde/0x140 [btrfs]
[162513.516650] ? finish_wait+0x90/0x90
[162513.516662] start_transaction+0x4d7/0x5f0 [btrfs]
[162513.516679] btrfs_setxattr_trans+0x3c/0x100 [btrfs]
[162513.516686] __vfs_setxattr+0x66/0x80
[162513.516691] __vfs_setxattr_noperm+0x70/0x200
[162513.516697] vfs_setxattr+0x6b/0x120
[162513.516703] setxattr+0x125/0x240
[162513.516709] ? lock_acquire+0xb1/0x480
[162513.516712] ? mnt_want_write+0x20/0x50
[162513.516721] ? rcu_read_lock_any_held+0x8e/0xb0
[162513.516723] ? preempt_count_add+0x49/0xa0
[162513.516725] ? __sb_start_write+0x19b/0x290
[162513.516727] ? preempt_count_add+0x49/0xa0
[162513.516732] path_setxattr+0xba/0xd0
[162513.516739] __x64_sys_setxattr+0x27/0x30
[162513.516741] do_syscall_64+0x33/0x80
[162513.516743] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.516745] RIP: 0033:0x7f5238f56d5a
[162513.516746] Code: Bad RIP value.
[162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc
[162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a
[162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470
[162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700
[162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004
[162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0
[162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds.
[162513.517064] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.517763] task:fsstress state:D stack: 0 pid:1356196 ppid:1356177 flags:0x00004000
[162513.517780] Call Trace:
[162513.517786] __schedule+0x5ce/0xd00
[162513.517789] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.517796] schedule+0x46/0xf0
[162513.517810] wait_current_trans+0xde/0x140 [btrfs]
[162513.517814] ? finish_wait+0x90/0x90
[162513.517829] start_transaction+0x37c/0x5f0 [btrfs]
[162513.517845] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
[162513.517857] btrfs_sync_fs+0x61/0x1c0 [btrfs]
[162513.517862] ? __ia32_sys_fdatasync+0x20/0x20
[162513.517865] iterate_supers+0x87/0xf0
[162513.517869] ksys_sync+0x60/0xb0
[162513.517872] __do_sys_sync+0xa/0x10
[162513.517875] do_syscall_64+0x33/0x80
[162513.517878] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.517881] RIP: 0033:0x7f5238f50bd7
[162513.517883] Code: Bad RIP value.
[162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
[162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
[162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053
[162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0
[162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053
[162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
[162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds.
[162513.518298] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.519157] task:fsstress state:D stack: 0 pid:1356197 ppid:1356177 flags:0x00000000
[162513.519160] Call Trace:
[162513.519165] __schedule+0x5ce/0xd00
[162513.519168] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.519174] schedule+0x46/0xf0
[162513.519190] wait_current_trans+0xde/0x140 [btrfs]
[162513.519193] ? finish_wait+0x90/0x90
[162513.519206] start_transaction+0x4d7/0x5f0 [btrfs]
[162513.519222] btrfs_create+0x57/0x200 [btrfs]
[162513.519230] lookup_open+0x522/0x650
[162513.519246] path_openat+0x2b8/0xa50
[162513.519270] do_filp_open+0x91/0x100
[162513.519275] ? find_held_lock+0x32/0x90
[162513.519280] ? lock_acquired+0x33b/0x470
[162513.519285] ? do_raw_spin_unlock+0x4b/0xc0
[162513.519287] ? _raw_spin_unlock+0x29/0x40
[162513.519295] do_sys_openat2+0x20d/0x2d0
[162513.519300] do_sys_open+0x44/0x80
[162513.519304] do_syscall_64+0x33/0x80
[162513.519307] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.519309] RIP: 0033:0x7f5238f4a903
[162513.519310] Code: Bad RIP value.
[162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
[162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903
[162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470
[162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002
[162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013
[162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620
[162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds.
[162513.519727] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.520508] task:btrfs state:D stack: 0 pid:1356211 ppid:1356178 flags:0x00004002
[162513.520511] Call Trace:
[162513.520516] __schedule+0x5ce/0xd00
[162513.520519] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.520525] schedule+0x46/0xf0
[162513.520544] btrfs_scrub_pause+0x11f/0x180 [btrfs]
[162513.520548] ? finish_wait+0x90/0x90
[162513.520562] btrfs_commit_transaction+0x45a/0xc30 [btrfs]
[162513.520574] ? start_transaction+0xe0/0x5f0 [btrfs]
[162513.520596] btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs]
[162513.520619] btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs]
[162513.520639] btrfs_ioctl+0x2a25/0x36f0 [btrfs]
[162513.520643] ? do_sigaction+0xf3/0x240
[162513.520645] ? find_held_lock+0x32/0x90
[162513.520648] ? do_sigaction+0xf3/0x240
[162513.520651] ? lock_acquired+0x33b/0x470
[162513.520655] ? _raw_spin_unlock_irq+0x24/0x50
[162513.520657] ? lockdep_hardirqs_on+0x7d/0x100
[162513.520660] ? _raw_spin_unlock_irq+0x35/0x50
[162513.520662] ? do_sigaction+0xf3/0x240
[162513.520671] ? __x64_sys_ioctl+0x83/0xb0
[162513.520672] __x64_sys_ioctl+0x83/0xb0
[162513.520677] do_syscall_64+0x33/0x80
[162513.520679] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.520681] RIP: 0033:0x7fc3cd307d87
[162513.520682] Code: Bad RIP value.
[162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87
[162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003
[162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003
[162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001
[162513.520703]
Showing all locks held in the system:
[162513.520712] 1 lock held by khungtaskd/54:
[162513.520713] #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197
[162513.520728] 1 lock held by in:imklog/596:
[162513.520729] #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60
[162513.520782] 1 lock held by btrfs-transacti/1356167:
[162513.520784] #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs]
[162513.520798] 1 lock held by btrfs/1356190:
[162513.520800] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60
[162513.520805] 1 lock held by fsstress/1356184:
[162513.520806] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
[162513.520811] 3 locks held by fsstress/1356185:
[162513.520812] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
[162513.520815] #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120
[162513.520820] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
[162513.520833] 1 lock held by fsstress/1356196:
[162513.520834] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
[162513.520838] 3 locks held by fsstress/1356197:
[162513.520839] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
[162513.520843] #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50
[162513.520846] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
[162513.520858] 2 locks held by btrfs/1356211:
[162513.520859] #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs]
[162513.520877] #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
This was weird because the stack traces show that a transaction commit,
triggered by a device replace operation, is blocking trying to pause any
running scrubs but there are no stack traces of blocked tasks doing a
scrub.
After poking around with drgn, I noticed there was a scrub task that was
constantly running and blocking for shorts periods of time:
>>> t = find_task(prog, 1356190)
>>> prog.stack_trace(t)
#0 __schedule+0x5ce/0xcfc
#1 schedule+0x46/0xe4
#2 schedule_timeout+0x1df/0x475
#3 btrfs_reada_wait+0xda/0x132
#4 scrub_stripe+0x2a8/0x112f
#5 scrub_chunk+0xcd/0x134
#6 scrub_enumerate_chunks+0x29e/0x5ee
#7 btrfs_scrub_dev+0x2d5/0x91b
#8 btrfs_ioctl+0x7f5/0x36e7
#9 __x64_sys_ioctl+0x83/0xb0
#10 do_syscall_64+0x33/0x77
#11 entry_SYSCALL_64+0x7c/0x156
Which corresponds to:
int btrfs_reada_wait(void *handle)
{
struct reada_control *rc = handle;
struct btrfs_fs_info *fs_info = rc->fs_info;
while (atomic_read(&rc->elems)) {
if (!atomic_read(&fs_info->reada_works_cnt))
reada_start_machine(fs_info);
wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0,
(HZ + 9) / 10);
}
(...)
So the counter "rc->elems" was set to 1 and never decreased to 0, causing
the scrub task to loop forever in that function. Then I used the following
script for drgn to check the readahead requests:
$ cat dump_reada.py
import sys
import drgn
from drgn import NULL, Object, cast, container_of, execscript, \
reinterpret, sizeof
from drgn.helpers.linux import *
mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"
mnt = None
for mnt in for_each_mount(prog, dst = mnt_path):
pass
if mnt is None:
sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
sys.exit(1)
fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)
def dump_re(re):
nzones = re.nzones.value_()
print(f're at {hex(re.value_())}')
print(f'\t logical {re.logical.value_()}')
print(f'\t refcnt {re.refcnt.value_()}')
print(f'\t nzones {nzones}')
for i in range(nzones):
dev = re.zones[i].device
name = dev.name.str.string_()
print(f'\t\t dev id {dev.devid.value_()} name {name}')
print()
for _, e in radix_tree_for_each(fs_info.reada_tree):
re = cast('struct reada_extent *', e)
dump_re(re)
$ drgn dump_reada.py
re at 0xffff8f3da9d25ad8
logical 38928384
refcnt 1
nzones 1
dev id 0 name b'/dev/sdd'
$
So there was one readahead extent with a single zone corresponding to the
source device of that last device replace operation logged in dmesg/syslog.
Also the ID of that zone's device was 0 which is a special value set in
the source device of a device replace operation when the operation finishes
(constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()),
confirming again that device /dev/sdd was the source of a device replace
operation.
Normally there should be as many zones in the readahead extent as there are
devices, and I wasn't expecting the extent to be in a block group with a
'single' profile, so I went and confirmed with the following drgn script
that there weren't any single profile block groups:
$ cat dump_block_groups.py
import sys
import drgn
from drgn import NULL, Object, cast, container_of, execscript, \
reinterpret, sizeof
from drgn.helpers.linux import *
mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"
mnt = None
for mnt in for_each_mount(prog, dst = mnt_path):
pass
if mnt is None:
sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
sys.exit(1)
fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)
BTRFS_BLOCK_GROUP_DATA = (1 << 0)
BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1)
BTRFS_BLOCK_GROUP_METADATA = (1 << 2)
BTRFS_BLOCK_GROUP_RAID0 = (1 << 3)
BTRFS_BLOCK_GROUP_RAID1 = (1 << 4)
BTRFS_BLOCK_GROUP_DUP = (1 << 5)
BTRFS_BLOCK_GROUP_RAID10 = (1 << 6)
BTRFS_BLOCK_GROUP_RAID5 = (1 << 7)
BTRFS_BLOCK_GROUP_RAID6 = (1 << 8)
BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9)
BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10)
def bg_flags_string(bg):
flags = bg.flags.value_()
ret = ''
if flags & BTRFS_BLOCK_GROUP_DATA:
ret = 'data'
if flags & BTRFS_BLOCK_GROUP_METADATA:
if len(ret) > 0:
ret += '|'
ret += 'meta'
if flags & BTRFS_BLOCK_GROUP_SYSTEM:
if len(ret) > 0:
ret += '|'
ret += 'system'
if flags & BTRFS_BLOCK_GROUP_RAID0:
ret += ' raid0'
elif flags & BTRFS_BLOCK_GROUP_RAID1:
ret += ' raid1'
elif flags & BTRFS_BLOCK_GROUP_DUP:
ret += ' dup'
elif flags & BTRFS_BLOCK_GROUP_RAID10:
ret += ' raid10'
elif flags & BTRFS_BLOCK_GROUP_RAID5:
ret += ' raid5'
elif flags & BTRFS_BLOCK_GROUP_RAID6:
ret += ' raid6'
elif flags & BTRFS_BLOCK_GROUP_RAID1C3:
ret += ' raid1c3'
elif flags & BTRFS_BLOCK_GROUP_RAID1C4:
ret += ' raid1c4'
else:
ret += ' single'
return ret
def dump_bg(bg):
print()
print(f'block group at {hex(bg.value_())}')
print(f'\t start {bg.start.value_()} length {bg.length.value_()}')
print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}')
bg_root = fs_info.block_group_cache_tree.address_of_()
for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'):
dump_bg(bg)
$ drgn dump_block_groups.py
block group at 0xffff8f3d673b0400
start 22020096 length 16777216
flags 258 - system raid6
block group at 0xffff8f3d53ddb400
start 38797312 length 536870912
flags 260 - meta raid6
block group at 0xffff8f3d5f4d9c00
start 575668224 length 2147483648
flags 257 - data raid6
block group at 0xffff8f3d08189000
start 2723151872 length 67108864
flags 258 - system raid6
block group at 0xffff8f3db70ff000
start 2790260736 length 1073741824
flags 260 - meta raid6
block group at 0xffff8f3d5f4dd800
start 3864002560 length 67108864
flags 258 - system raid6
block group at 0xffff8f3d67037000
start 3931111424 length 2147483648
flags 257 - data raid6
$
So there were only 2 reasons left for having a readahead extent with a
single zone: reada_find_zone(), called when creating a readahead extent,
returned NULL either because we failed to find the corresponding block
group or because a memory allocation failed. With some additional and
custom tracing I figured out that on every further ocurrence of the
problem the block group had just been deleted when we were looping to
create the zones for the readahead extent (at reada_find_extent()), so we
ended up with only one zone in the readahead extent, corresponding to a
device that ends up getting replaced.
So after figuring that out it became obvious why the hang happens:
1) Task A starts a scrub on any device of the filesystem, except for
device /dev/sdd;
2) Task B starts a device replace with /dev/sdd as the source device;
3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently
starting to scrub a stripe from block group X. This call to
btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add()
calls reada_add_block(), it passes the logical address of the extent
tree's root node as its 'logical' argument - a value of 38928384;
4) Task A then enters reada_find_extent(), called from reada_add_block().
It finds there isn't any existing readahead extent for the logical
address 38928384, so it proceeds to the path of creating a new one.
It calls btrfs_map_block() to find out which stripes exist for the block
group X. On the first iteration of the for loop that iterates over the
stripes, it finds the stripe for device /dev/sdd, so it creates one
zone for that device and adds it to the readahead extent. Before getting
into the second iteration of the loop, the cleanup kthread deletes block
group X because it was empty. So in the iterations for the remaining
stripes it does not add more zones to the readahead extent, because the
calls to reada_find_zone() returned NULL because they couldn't find
block group X anymore.
As a result the new readahead extent has a single zone, corresponding to
the device /dev/sdd;
4) Before task A returns to btrfs_reada_add() and queues the readahead job
for the readahead work queue, task B finishes the device replace and at
btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new
device /dev/sdg;
5) Task A returns to reada_add_block(), which increments the counter
"->elems" of the reada_control structure allocated at btrfs_reada_add().
Then it returns back to btrfs_reada_add() and calls
reada_start_machine(). This queues a job in the readahead work queue to
run the function reada_start_machine_worker(), which calls
__reada_start_machine().
At __reada_start_machine() we take the device list mutex and for each
device found in the current device list, we call
reada_start_machine_dev() to start the readahead work. However at this
point the device /dev/sdd was already freed and is not in the device
list anymore.
This means the corresponding readahead for the extent at 38928384 is
never started, and therefore the "->elems" counter of the reada_control
structure allocated at btrfs_reada_add() never goes down to 0, causing
the call to btrfs_reada_wait(), done by the scrub task, to wait forever.
Note that the readahead request can be made either after the device replace
started or before it started, however in pratice it is very unlikely that a
device replace is able to start after a readahead request is made and is
able to complete before the readahead request completes - maybe only on a
very small and nearly empty filesystem.
This hang however is not the only problem we can have with readahead and
device removals. When the readahead extent has other zones other than the
one corresponding to the device that is being removed (either by a device
replace or a device remove operation), we risk having a use-after-free on
the device when dropping the last reference of the readahead extent.
For example if we create a readahead extent with two zones, one for the
device /dev/sdd and one for the device /dev/sde:
1) Before the readahead worker starts, the device /dev/sdd is removed,
and the corresponding btrfs_device structure is freed. However the
readahead extent still has the zone pointing to the device structure;
2) When the readahead worker starts, it only finds device /dev/sde in the
current device list of the filesystem;
3) It starts the readahead work, at reada_start_machine_dev(), using the
device /dev/sde;
4) Then when it finishes reading the extent from device /dev/sde, it calls
__readahead_hook() which ends up dropping the last reference on the
readahead extent through the last call to reada_extent_put();
5) At reada_extent_put() it iterates over each zone of the readahead extent
and attempts to delete an element from the device's 'reada_extents'
radix tree, resulting in a use-after-free, as the device pointer of the
zone for /dev/sdd is now stale. We can also access the device after
dropping the last reference of a zone, through reada_zone_release(),
also called by reada_extent_put().
And a device remove suffers the same problem, however since it shrinks the
device size down to zero before removing the device, it is very unlikely to
still have readahead requests not completed by the time we free the device,
the only possibility is if the device has a very little space allocated.
While the hang problem is exclusive to scrub, since it is currently the
only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free
problem affects any path that triggers readhead, which includes
btree_readahead_hook() and __readahead_hook() (a readahead worker can
trigger readahed for the children of a node) for example - any path that
ends up calling reada_add_block() can trigger the use-after-free after a
device is removed.
So fix this by waiting for any readahead requests for a device to complete
before removing a device, ensuring that while waiting for existing ones no
new ones can be made.
This problem has been around for a very long time - the readahead code was
added in 2011, device remove exists since 2008 and device replace was
introduced in 2013, hard to pick a specific commit for a git Fixes tag.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's no longer used just remove the function and any related code which
was initialising it for inodes. No functional changes.
Removing 8 bytes from extent_io_tree in turn reduces size of other
structures where it is embedded, notably btrfs_inode where it reduces
size by 24 bytes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead export and rename the function to btrfs_submit_data_bio and
call it directly in submit_one_bio. This avoids paying the cost for
speculative attacks mitigations and improves code readability.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Don't call readpage_end_io_hook for the btree inode. Instead of relying
on indirect calls to implement metadata buffer validation simply check
if the inode whose page we are processing equals the btree inode. If it
does call the necessary function.
This is an improvement in 2 directions:
1. We aren't paying the penalty of indirect calls in a post-speculation
attacks world.
2. The function is now named more explicitly so it's obvious what's
going on
This is in preparation to removing struct extent_io_ops altogether.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the definitions generated by BTRFS_SETGET_HEADER_FUNCS there's direct
pointer assignment but we should use the helpers for unaligned access
for clarity. It hasn't been a problem so far because of the natural
alignment.
Similarly for BTRFS_SETGET_STACK_FUNCS, that usually get a structure
from stack that has an aligned start but some members may not be aligned
due to packing. This as well hasn't caused problems so far.
Move the put/get_unaligned_le8 stubs to ctree.h so we can use them.
Signed-off-by: David Sterba <dsterba@suse.com>
That parameter can easily be derived based on the "data_size" and "nr"
parameters exploit this fact to simply the function's signature. No
functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value of this argument can be derived from the total_data as it's
simply the value of the data size + size of btrfs_items being touched.
Move the parameter calculation inside the function. This results in a
simpler interface and also a minor size reduction:
./scripts/bloat-o-meter ctree.original fs/btrfs/ctree.o
add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-34 (-34)
Function old new delta
btrfs_duplicate_item 260 259 -1
setup_items_for_insert 1200 1190 -10
btrfs_insert_empty_items 177 154 -23
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function btrfs_punch_hole_range() is now used to replace all the file
extents in a given file range with an extent described in the given struct
btrfs_replace_extent_info argument. This extent can either be an existing
extent that is being cloned or it can be a new extent (namely a prealloc
extent). When that argument is NULL it only punches a hole (drops all the
existing extents) in the file range.
So rename the function to btrfs_replace_file_extents().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we can use btrfs_clone_extent_info to convey information for a
new prealloc extent as well, and not just for existing extents that are
being cloned, rename it to btrfs_replace_extent_info, which reflects the
fact that this is now more generic and it is used to replace all existing
extents in a file range with the extent described by the structure.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value of item_size of struct btrfs_clone_extent_info is always set to
the size of a non-inline file extent item, and in fact the infrastructure
that uses this structure (btrfs_punch_hole_range()) does not work with
inline file extents at all (and it is not supposed to).
So just remove that field from the structure and use directly
sizeof(struct btrfs_file_extent_item) instead. Also assert that the
file extent type is not inline at btrfs_insert_clone_extent().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When doing an fallocate(), specially a zero range operation, we assume
that reserving 3 units of metadata space is enough, that at most we touch
one leaf in subvolume/fs tree for removing existing file extent items and
inserting a new file extent item. This assumption is generally true for
most common use cases. However when we end up needing to remove file extent
items from multiple leaves, we can end up failing with -ENOSPC and abort
the current transaction, turning the filesystem to RO mode. When this
happens a stack trace like the following is dumped in dmesg/syslog:
[ 1500.620934] ------------[ cut here ]------------
[ 1500.620938] BTRFS: Transaction aborted (error -28)
[ 1500.620973] WARNING: CPU: 2 PID: 30807 at fs/btrfs/inode.c:9724 __btrfs_prealloc_file_range+0x512/0x570 [btrfs]
[ 1500.620974] Modules linked in: btrfs intel_rapl_msr intel_rapl_common kvm_intel (...)
[ 1500.621010] CPU: 2 PID: 30807 Comm: xfs_io Tainted: G W 5.9.0-rc3-btrfs-next-67 #1
[ 1500.621012] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[ 1500.621023] RIP: 0010:__btrfs_prealloc_file_range+0x512/0x570 [btrfs]
[ 1500.621026] Code: 8b 40 50 f0 48 (...)
[ 1500.621028] RSP: 0018:ffffb05fc8803ca0 EFLAGS: 00010286
[ 1500.621030] RAX: 0000000000000000 RBX: ffff9608af276488 RCX: 0000000000000000
[ 1500.621032] RDX: 0000000000000001 RSI: 0000000000000027 RDI: 00000000ffffffff
[ 1500.621033] RBP: ffffb05fc8803d90 R08: 0000000000000001 R09: 0000000000000001
[ 1500.621035] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000003200000
[ 1500.621037] R13: 00000000ffffffe4 R14: ffff9608af275fe8 R15: ffff9608af275f60
[ 1500.621039] FS: 00007fb5b2368ec0(0000) GS:ffff9608b6600000(0000) knlGS:0000000000000000
[ 1500.621041] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1500.621043] CR2: 00007fb5b2366fb8 CR3: 0000000202d38005 CR4: 00000000003706e0
[ 1500.621046] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1500.621047] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1500.621049] Call Trace:
[ 1500.621076] btrfs_prealloc_file_range+0x10/0x20 [btrfs]
[ 1500.621087] btrfs_fallocate+0xccd/0x1280 [btrfs]
[ 1500.621108] vfs_fallocate+0x14d/0x290
[ 1500.621112] ksys_fallocate+0x3a/0x70
[ 1500.621117] __x64_sys_fallocate+0x1a/0x20
[ 1500.621120] do_syscall_64+0x33/0x80
[ 1500.621123] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 1500.621126] RIP: 0033:0x7fb5b248c477
[ 1500.621128] Code: 89 7c 24 08 (...)
[ 1500.621130] RSP: 002b:00007ffc7bee9060 EFLAGS: 00000293 ORIG_RAX: 000000000000011d
[ 1500.621132] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fb5b248c477
[ 1500.621134] RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000003
[ 1500.621136] RBP: 0000557718faafd0 R08: 0000000000000000 R09: 0000000000000000
[ 1500.621137] R10: 0000000003200000 R11: 0000000000000293 R12: 0000000000000010
[ 1500.621139] R13: 0000557718faafb0 R14: 0000557718faa480 R15: 0000000000000003
[ 1500.621151] irq event stamp: 1026217
[ 1500.621154] hardirqs last enabled at (1026223): [<ffffffffba965570>] console_unlock+0x500/0x5c0
[ 1500.621156] hardirqs last disabled at (1026228): [<ffffffffba9654c7>] console_unlock+0x457/0x5c0
[ 1500.621159] softirqs last enabled at (1022486): [<ffffffffbb6003dc>] __do_softirq+0x3dc/0x606
[ 1500.621161] softirqs last disabled at (1022477): [<ffffffffbb4010b2>] asm_call_on_stack+0x12/0x20
[ 1500.621162] ---[ end trace 2955b08408d8b9d4 ]---
[ 1500.621167] BTRFS: error (device sdj) in __btrfs_prealloc_file_range:9724: errno=-28 No space left
When we use fallocate() internally, for reserving an extent for a space
cache, inode cache or relocation, we can't hit this problem since either
there aren't any file extent items to remove from the subvolume tree or
there is at most one.
When using plain fallocate() it's very unlikely, since that would require
having many file extent items representing holes for the target range and
crossing multiple leafs - we attempt to increase the range (merge) of such
file extent items when punching holes, so at most we end up with 2 file
extent items for holes at leaf boundaries.
However when using the zero range operation of fallocate() for a large
range (100+ MiB for example) that's fairly easy to trigger. The following
example reproducer triggers the issue:
$ cat reproducer.sh
#!/bin/bash
umount /dev/sdj &> /dev/null
mkfs.btrfs -f -n 16384 -O ^no-holes /dev/sdj > /dev/null
mount /dev/sdj /mnt/sdj
# Create a 100M file with many file extent items. Punch a hole every 8K
# just to speedup the file creation - we could do 4K sequential writes
# followed by fsync (or O_SYNC) as well, but that takes a lot of time.
file_size=$((100 * 1024 * 1024))
xfs_io -f -c "pwrite -S 0xab -b 10M 0 $file_size" /mnt/sdj/foobar
for ((i = 0; i < $file_size; i += 8192)); do
xfs_io -c "fpunch $i 4096" /mnt/sdj/foobar
done
# Force a transaction commit, so the zero range operation will be forced
# to COW all metadata extents it need to touch.
sync
xfs_io -c "fzero 0 $file_size" /mnt/sdj/foobar
umount /mnt/sdj
$ ./reproducer.sh
wrote 104857600/104857600 bytes at offset 0
100 MiB, 10 ops; 0.0669 sec (1.458 GiB/sec and 149.3117 ops/sec)
fallocate: No space left on device
$ dmesg
<shows the same stack trace pasted before>
To fix this use the existing infrastructure that hole punching and
extent cloning use for replacing a file range with another extent. This
deals with doing the removal of file extent items and inserting the new
one using an incremental approach, reserving more space when needed and
always ensuring we don't leave an implicit hole in the range in case
we need to do multiple iterations and a crash happens between iterations.
A test case for fstests will follow up soon.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of using a flag bit for exclusive operation, use a variable to
store which exclusive operation is being performed. Introduce an API
to start and finish an exclusive operation.
This would enable another way for tools to check which operation is
running on why starting an exclusive operation failed. The followup
patch adds a sysfs_notify() to alert userspace when the state changes, so
userspace can perform select() on it to get notified of the change.
This would enable us to enqueue a command which will wait for current
exclusive operation to complete before issuing the next exclusive
operation. This has been done synchronously as opposed to a background
process, or else error collection (if any) will become difficult.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
It's counterintuitive to have a function named btrfs_inode_xxx which
takes a generic inode. Also move the function to btrfs_inode.h so that
it has access to the definition of struct btrfs_inode.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we COW a block we are holding a lock on the original block, and
then we lock the new COW block. Because our lockdep maps are based on
root + level, this will make lockdep complain. We need a way to
indicate a subclass for locking the COW'ed block, so plumb through our
btrfs_lock_nesting from btrfs_cow_block down to the btrfs_init_buffer,
and then introduce BTRFS_NESTING_COW to be used for cow'ing blocks.
The reason I've added all this extra infrastructure is because there
will be need of different nesting classes in follow up patches.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Our current tree locking stuff allows us to recurse with read locks if
we're already holding the write lock. This is necessary for the space
cache inode, as we could be holding a lock on the root_tree root when we
need to cache a block group, and thus need to be able to read down the
root_tree to read in the inode cache.
We can get away with this in our current locking, but we won't be able
to with a rwsem. Handle this by purposefully annotating the places
where we require recursion, so that in the future we can maybe come up
with a way to avoid the recursion. In the case of the free space inode,
this will be superseded by the free space tree.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
When quota is enabled for TEST_DEV, generic/013 sometimes fails like this:
generic/013 14s ... _check_dmesg: something found in dmesg (see xfstests-dev/results//generic/013.dmesg)
And with the following metadata leak:
BTRFS warning (device dm-3): qgroup 0/1370 has unreleased space, type 2 rsv 49152
------------[ cut here ]------------
WARNING: CPU: 2 PID: 47912 at fs/btrfs/disk-io.c:4078 close_ctree+0x1dc/0x323 [btrfs]
Call Trace:
btrfs_put_super+0x15/0x17 [btrfs]
generic_shutdown_super+0x72/0x110
kill_anon_super+0x18/0x30
btrfs_kill_super+0x17/0x30 [btrfs]
deactivate_locked_super+0x3b/0xa0
deactivate_super+0x40/0x50
cleanup_mnt+0x135/0x190
__cleanup_mnt+0x12/0x20
task_work_run+0x64/0xb0
__prepare_exit_to_usermode+0x1bc/0x1c0
__syscall_return_slowpath+0x47/0x230
do_syscall_64+0x64/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
---[ end trace a6cfd45ba80e4e06 ]---
BTRFS error (device dm-3): qgroup reserved space leaked
BTRFS info (device dm-3): disk space caching is enabled
BTRFS info (device dm-3): has skinny extents
[CAUSE]
The qgroup preallocated meta rsv operations of that offending root are:
btrfs_delayed_inode_reserve_metadata: rsv_meta_prealloc root=1370 num_bytes=131072
btrfs_delayed_inode_reserve_metadata: rsv_meta_prealloc root=1370 num_bytes=131072
btrfs_subvolume_reserve_metadata: rsv_meta_prealloc root=1370 num_bytes=49152
btrfs_delayed_inode_release_metadata: convert_meta_prealloc root=1370 num_bytes=-131072
btrfs_delayed_inode_release_metadata: convert_meta_prealloc root=1370 num_bytes=-131072
It's pretty obvious that, we reserve qgroup meta rsv in
btrfs_subvolume_reserve_metadata(), but doesn't have corresponding
release/convert calls in btrfs_subvolume_release_metadata().
This leads to the leakage.
[FIX]
To fix this bug, we should follow what we're doing in
btrfs_delalloc_reserve_metadata(), where we reserve qgroup space, and
add it to block_rsv->qgroup_rsv_reserved.
And free the qgroup reserved metadata space when releasing the
block_rsv.
To do this, we need to change the btrfs_subvolume_release_metadata() to
accept btrfs_root, and record the qgroup_to_release number, and call
btrfs_qgroup_convert_reserved_meta() for it.
Fixes: 733e03a0b2 ("btrfs: qgroup: Split meta rsv type into meta_prealloc and meta_pertrans")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're using direct io implementation based on buffer heads. This patch
switches to the new iomap infrastructure.
Switch from __blockdev_direct_IO() to iomap_dio_rw(). Rename
btrfs_get_blocks_direct() to btrfs_dio_iomap_begin() and use it as
iomap_begin() for iomap direct I/O functions. This function allocates
and locks all the blocks required for the I/O. btrfs_submit_direct() is
used as the submit_io() hook for direct I/O ops.
Since we need direct I/O reads to go through iomap_dio_rw(), we change
file_operations.read_iter() to a btrfs_file_read_iter() which calls
btrfs_direct_IO() for direct reads and falls back to
generic_file_buffered_read() for incomplete reads and buffered reads.
We don't need address_space.direct_IO() anymore: set it to noop.
Similarly, we don't need flags used in __blockdev_direct_IO(). iomap is
capable of direct I/O reads from a hole, so we don't need to return
-ENOENT.
Btrfs direct I/O is now done under i_rwsem, shared in case of reads and
exclusive in case of writes. This guards against simultaneous truncates.
Use iomap->iomap_end() to check for failed or incomplete direct I/O:
- for writes, call __endio_write_update_ordered()
- for reads, unlock extents
btrfs_dio_data is now hooked in iomap->private and not
current->journal_info. It carries the reservation variable and the
amount of data submitted, so we can calculate the amount of data to call
__endio_write_update_ordered in case of an error.
This patch removes last use of struct buffer_head from btrfs.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have the data ticketing stuff in place, move normal data
reservations to use an async reclaim helper to satisfy tickets. Before
we could have multiple tasks race in and both allocate chunks, resulting
in more data chunks than we would necessarily need. Serializing these
allocations and making a single thread responsible for flushing will
only allocate chunks as needed, as well as cut down on transaction
commits and other flush related activities.
Priority reservations will still work as they have before, simply
trying to allocate a chunk until they can make their reservation.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently the way we do data reservations is by seeing if we have enough
space in our space_info. If we do not and we're a normal inode we'll
1) Attempt to force a chunk allocation until we can't anymore.
2) If that fails we'll flush delalloc, then commit the transaction, then
run the delayed iputs.
If we are a free space inode we're only allowed to force a chunk
allocation. In order to use the normal flushing mechanism we need to
encode this into a flush state array for normal inodes. Since both will
start with allocating chunks until the space info is full there is no
need to add this as a flush state, this will be handled specially.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have btrfs_wait_ordered_roots() which takes a u64 for nr, but
btrfs_start_delalloc_roots() that takes an int for nr, which makes using
them in conjunction, especially for something like (u64)-1, annoying and
inconsistent. Fix btrfs_start_delalloc_roots() to take a u64 for nr and
adjust start_delalloc_inodes() and it's callers appropriately.
This means we've adjusted start_delalloc_inodes() to take a pointer of
nr since we want to preserve the ability for start-delalloc_inodes() to
return an error, so simply make it do the nr adjusting as necessary.
Part of adjusting the callers to this means changing
btrfs_writeback_inodes_sb_nr() to take a u64 for items. This may be
confusing because it seems unrelated, but the caller of
btrfs_writeback_inodes_sb_nr() already passes in a u64, it's just the
function variable that needs to be changed.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
