There are no concerns about locking during the selftests so the locks
are not necessary, but following patches will add lockdep assertions to
add_extent_mapping so this is needed in tests too.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function has a lot of return values and specific conventions making
it cumbersome to understand what's returned. Have a go at documenting
its parameters and return values.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently find_first_clear_extent_bit always returns a range whose
starting value is >= passed 'start'. This implicit trimming behavior is
somewhat subtle and an implementation detail.
Instead, this patch modifies the function such that now it always
returns the range which contains passed 'start' and has the given bits
unset. This range could either be due to presence of existing records
which contains 'start' but have the bits unset or because there are no
records that contain the given starting offset.
This patch also adds test cases which cover find_first_clear_extent_bit
since they were missing up until now.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently the first megabyte on a device housing a btrfs filesystem is
exempt from allocation and trimming. Currently this is not a problem
since 'start' is set to 1M at the beginning of btrfs_trim_free_extents
and find_first_clear_extent_bit always returns a range that is >= start.
However, in a follow up patch find_first_clear_extent_bit will be
changed such that it will return a range containing 'start' and this
range may very well be 0...>=1M so 'start'.
Future proof the sole user of find_first_clear_extent_bit by setting
'start' after the function is called. No functional changes.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The filename:line format is commonly understood by editors and can be
copy&pasted more easily than the current format.
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_print_data_csum_error() still assumed checksums to be 32 bit in
size. Make it size agnostic.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs_csum_data() relied on the crc32c() wrapper around the
crypto framework for calculating the CRCs.
As we have our own crypto_shash structure in the fs_info now, we can
directly call into the crypto framework without going trough the wrapper.
This way we can even remove the btrfs_csum_data() and btrfs_csum_final()
wrappers.
The module dependency on crc32c is preserved via MODULE_SOFTDEP("pre:
crc32c"), which was previously provided by LIBCRC32C config option doing
the same.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add boilerplate code for directly including the crypto framework. This
helps us flipping the switch for new algorithms.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have already checked for a valid checksum type before
calling btrfs_check_super_csum(), it can be simplified even further.
While at it get rid of the implicit size assumption of the resulting
checksum as well.
This is a preparation for changing all checksum functionality to use the
crypto layer later.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have factorerd out the superblock checksum type validation,
we can check for supported superblock checksum types before doing the
actual validation of the superblock read from disk.
This leads the path to further simplifications of
btrfs_check_super_csum() later on.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs is only supporting CRC32C as checksumming algorithm. As
this is about to change provide a function to validate the checksum type
in the superblock against all possible algorithms.
This makes adding new algorithms easier as there are fewer places to
adjust when adding new algorithms.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add a small helper for btrfs_print_data_csum_error() which formats the
checksum according to it's type for pretty printing.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ shorten macro name ]
Signed-off-by: David Sterba <dsterba@suse.com>
BTRFS has the implicit assumption that a checksum in compressed_bio is 4
bytes. While this is true for CRC32C, it is not for any other checksum.
Change the data type to be a byte array and adjust loop index calculation
accordingly.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
BTRFS has the implicit assumption that a checksum in btrfs_orderd_sums
is 4 bytes. While this is true for CRC32C, it is not for any other
checksum.
Change the data type to be a byte array and adjust loop index
calculation accordingly.
This includes moving the adjustment of 'index' by 'ins_size' in
btrfs_csum_file_blocks() before dividing 'ins_size' by the checksum
size, because before this patch the 'sums' member of 'struct
btrfs_ordered_sum' was 4 Bytes in size and afterwards it is only one
byte.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The CRC checksum in the free space cache is not dependant on the super
block's csum_type field but always a CRC32C.
So use btrfs_crc32c() and btrfs_crc32c_final() instead of
btrfs_csum_data() and btrfs_csum_final() for computing these checksums.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 9678c54388 ("btrfs: Remove custom crc32c init code") removed
the btrfs_crc32c() function, because it was a duplicate of the crc32c()
library function we already have in the kernel.
Resurrect it as a shim wrapper over crc32c() to make following
transformations of the checksumming code in btrfs easier.
Also provide a btrfs_crc32_final() to ease following transformations.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfsic_test_for_metadata() directly calls the crc32c() library function
for calculating the CRC32C checksum, but then uses btrfs_csum_final() to
invert the result.
To ease further refactoring and development around checksumming in BTRFS
convert to calling btrfs_csum_data(), which is a wrapper around
crc32c().
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
The following script can cause unexpected fsync failure:
#!/bin/bash
dev=/dev/test/test
mnt=/mnt/btrfs
mkfs.btrfs -f $dev -b 512M > /dev/null
mount $dev $mnt -o nospace_cache
# Prealloc one extent
xfs_io -f -c "falloc 8k 64m" $mnt/file1
# Fill the remaining data space
xfs_io -f -c "pwrite 0 -b 4k 512M" $mnt/padding
sync
# Write into the prealloc extent
xfs_io -c "pwrite 1m 16m" $mnt/file1
# Reflink then fsync, fsync would fail due to ENOSPC
xfs_io -c "reflink $mnt/file1 8k 0 4k" -c "fsync" $mnt/file1
umount $dev
The fsync fails with ENOSPC, and the last page of the buffered write is
lost.
[CAUSE]
This is caused by:
- Btrfs' back reference only has extent level granularity
So write into shared extent must be COWed even only part of the extent
is shared.
So for above script we have:
- fallocate
Create a preallocated extent where we can do NOCOW write.
- fill all the remaining data and unallocated space
- buffered write into preallocated space
As we have not enough space available for data and the extent is not
shared (yet) we fall into NOCOW mode.
- reflink
Now part of the large preallocated extent is shared, later write
into that extent must be COWed.
- fsync triggers writeback
But now the extent is shared and therefore we must fallback into COW
mode, which fails with ENOSPC since there's not enough space to
allocate data extents.
[WORKAROUND]
The workaround is to ensure any buffered write in the related extents
(not just the reflink source range) get flushed before reflink/dedupe,
so that NOCOW writes succeed that happened before reflinking succeed.
The workaround is expensive, we could do it better by only flushing
NOCOW range, but that needs extra accounting for NOCOW range.
For now, fix the possible data loss first.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The first thing code does in check_can_nocow is trying to block
concurrent snapshots. If this fails (due to snpashot already being in
progress) the function returns ENOSPC which makes no sense. Instead
return EAGAIN. Despite this return value not being propagated to callers
it's good practice to return the closest in terms of semantics error
code. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In case no cached_state argument is passed to
btrfs_lock_and_flush_ordered_range use one locally in the function. This
optimises the case when an ordered extent is found since the unlock
function will be able to unlock that state directly without searching
for it again.
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>
There several functions which open code
btrfs_lock_and_flush_ordered_range, just replace them with a call to the
function. 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>
There is a certain idiom used in multiple places in btrfs' codebase,
dealing with flushing an ordered range. Factor this in a separate
function that can be reused. Future patches will replace the existing
code with that function.
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>
At the context of btrfs_run_delalloc_range(), we haven't started/joined
a transaction, thus even something went wrong, we can't and won't abort
transaction, thus no way to make the fs RO.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Just add a safe net for btrfs_space_info member updating.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The helper lacks the btrfs_ prefix and the parameter is the raw
blockgroup type, so none of the callers has to do the flags -> index
conversion.
Signed-off-by: David Sterba <dsterba@suse.com>
The raid_attr table is now 7 * 56 = 392 bytes long, consisting of just
small numbers so we don't have to use ints. New size is 7 * 32 = 224,
saving 3 cachelines.
Signed-off-by: David Sterba <dsterba@suse.com>
Factor the sequence of ifs to a helper, the 'data stripes' here means
the number of stripes without redundancy and parity.
Signed-off-by: David Sterba <dsterba@suse.com>
Replace open coded list of the profiles by selecting them from the
raid_attr table. The criteria are now more explicit, we need profiles
that have more than 1 copy of the data or can reconstruct the data with
a missing device.
Signed-off-by: David Sterba <dsterba@suse.com>
Iterate over the table and gather all allowed profiles for a given
number of devices, instead of open coding.
Signed-off-by: David Sterba <dsterba@suse.com>
fs_info::mapping_tree is the physical<->logical mapping tree and uses
the same underlying structure as extents, but is embedded to another
structure. There are no other members and this indirection is useless.
No functional change.
Signed-off-by: David Sterba <dsterba@suse.com>
The minimum number of devices for RAID5 is 2, though this is only a bit
expensive RAID1, and for RAID6 it's 3, which is a triple copy that works
only 3 devices.
mkfs.btrfs allows that and mounting such filesystem also works, so the
conversion via balance filters is inconsistent with the others and we
should not prevent it.
Signed-off-by: David Sterba <dsterba@suse.com>
The list of profiles in btrfs_chunk_max_errors lists DUP as a profile
DUP able to tolerate 1 device missing. Though this profile is special
with 2 copies, it still needs the device, unlike the others.
Looking at the history of changes, thre's no clear reason why DUP is
there, functions were refactored and blocks of code merged to one
helper.
d20983b40e Btrfs: fix writing data into the seed filesystem
- factor code to a helper
de11cc12df Btrfs: don't pre-allocate btrfs bio
- unrelated change, DUP still in the list with max errors 1
a236aed14c Btrfs: Deal with failed writes in mirrored configurations
- introduced the max errors, leaves DUP and RAID1 in the same group
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This code was first introduced in 5f39d397df ("Btrfs: Create
extent_buffer interface for large blocksizes") and the function was
named btrfs_unlink_trans. It later got renamed to __btrfs_unlink_inode
and finally commit 16cdcec736 ("btrfs: implement delayed inode items
operation") changed the way inodes are deleted and obviated the need for
those two members.
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ replace changelog by Nikolay's version ]
Signed-off-by: David Sterba <dsterba@suse.com>
This is a leftover from 312c89fbca ("btrfs: cleanup btrfs_mount()
using btrfs_mount_root()"), the mode was used for opening devices that's
not done here anymore.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In function do_trimming(), block_group->lock should be unlocked first,
as the locks should be released in the reverse order. This does not
cause problems but should follow the best practices.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
Under certain conditions, we could have strange file extent item in log
tree like:
item 18 key (69599 108 397312) itemoff 15208 itemsize 53
extent data disk bytenr 0 nr 0
extent data offset 0 nr 18446744073709547520 ram 18446744073709547520
The num_bytes + ram_bytes overflow 64 bit type.
For num_bytes part, we can detect such overflow along with file offset
(key->offset), as file_offset + num_bytes should never go beyond u64.
For ram_bytes part, it's about the decompressed size of the extent, not
directly related to the size.
In theory it is OK to have a large value, and put extra limitation
on RAM bytes may cause unexpected false alerts.
So in tree-checker, we only check if the file offset and num bytes
overflow.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is already done in btrfs_init_dev_replace_tgtdev which is the first
phase of device replace, called before doing scrub. During that time
exclusive lock is held. Additionally btrfs_fs_device::commit_total_bytes
is always set based on the size of the underlying block device which
shouldn't change once set. This makes the 2nd assignment of the variable
in the finishing phase redundant.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Part of device replace involves writing an item to the device root
containing information about pending replace operations. Currently space
for this item is not being explicitly reserved so this works thanks to
presence of global reserve. While not fatal it's not a good practice.
Let's be explicit about space requirement of device replace and reserve
space when starting the transaction.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are only 2 branches which goto leave label with need_unlock set
to true. Essentially need_unlock is used as a substitute for directly
calling up_write. Since the branches needing this are only 2 and their
context is not that big it's more clear to just call up_write where
required. No functional changes.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_init_dev_replace_tgtdev reads certain values from the source
device (such as commit_total_bytes) which are updated during transaction
commit. Currently this function is called before committing any pending
transaction, leading to possibly reading outdated values.
Fix this by moving the function below the transaction commit, at this
point the EXCL_OP bit it set hence once transaction is complete the
total size of the device cannot be changed (it's usually changed by
resize/remove ops which are blocked).
Fixes: 9e271ae27e ("Btrfs: kernel operation should come after user input has been verified")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This WARN_ON can never trigger because src_device cannot be null.
btrfs_find_device_by_devspec always returns either an error or a valid
pointer to the device. Just remove it.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is no point in holding btrfs_fs_devices::device_list_mutex
while initialising fields of the not-yet-published device. Instead,
hold the mutex only when the newly initialised device is being
published. I think holding device_list_mutex here is redundant
altogether, because at this point BTRFS_FS_EXCL_OP is set which
prevents device removal/addition/balance/resize to occur.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
