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83002 commits

Author SHA1 Message Date
Naohiro Aota
0356ad41e0 btrfs: zoned: defer advancing meta write pointer
We currently advance the meta_write_pointer in
btrfs_check_meta_write_pointer(). That makes it necessary to revert it
when locking the buffer failed. Instead, we can advance it just before
sending the buffer.

Also, this is necessary for the following commit. In the commit, it needs
to release the zoned_meta_io_lock to allow IOs to come in and wait for them
to fill the currently active block group. If we advance the
meta_write_pointer before locking the extent buffer, the following extent
buffer can pass the meta_write_pointer check, resulting in an unaligned
write failure.

Advancing the pointer is still thread-safe as the extent buffer is locked.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
2023-08-21 14:52:19 +02:00
Naohiro Aota
2ad8c0510a btrfs: zoned: return int from btrfs_check_meta_write_pointer
Now that we have writeback_control passed to
btrfs_check_meta_write_pointer(), we can move the wbc condition in
submit_eb_page() to btrfs_check_meta_write_pointer() and return int.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
2023-08-21 14:52:19 +02:00
Naohiro Aota
7db94301a9 btrfs: zoned: introduce block group context to btrfs_eb_write_context
For metadata write out on the zoned mode, we call
btrfs_check_meta_write_pointer() to check if an extent buffer to be written
is aligned to the write pointer.

We look up a block group containing the extent buffer for every extent
buffer, which takes unnecessary effort as the writing extent buffers are
mostly contiguous.

Introduce "zoned_bg" to cache the block group working on.  Also, while
at it, rename "cache" to "block_group".

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
2023-08-21 14:52:19 +02:00
Naohiro Aota
861093eff4 btrfs: introduce struct to consolidate extent buffer write context
Introduce btrfs_eb_write_context to consolidate writeback_control and the
exntent buffer context.  This will help adding a block group context as
well.

While at it, move the eb context setting before
btrfs_check_meta_write_pointer(). We can set it here because we anyway need
to skip pages in the same eb if that eb is rejected by
btrfs_check_meta_write_pointer().

Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
2023-08-21 14:52:19 +02:00
Filipe Manana
9c93c238c1 btrfs: avoid start and commit empty transaction when flushing qgroups
When flushing qgroups, we try to join a running transaction, with
btrfs_join_transaction(), and then commit the transaction. However using
btrfs_join_transaction() will result in creating a new transaction in case
there isn't any running or if there's an existing one already committing.
This is pointless as we only need to attach to an existing one that is
not committing and in case there's an existing one committing, wait for
its commit to complete. Creating and committing an empty transaction is
wasteful, pointless IO and unnecessary rotation of the backup roots.

So use btrfs_attach_transaction_barrier() instead, to avoid creating and
committing empty transactions.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
6705b48a50 btrfs: avoid start and commit empty transaction when starting qgroup rescan
When starting a qgroup rescan, we try to join a running transaction, with
btrfs_join_transaction(), and then commit the transaction. However using
btrfs_join_transaction() will result in creating a new transaction in case
there isn't any running or if there's an existing one already committing.
This is pointless as we only need to attach to an existing one that is
not committing and in case there's an existing one committing, wait for
its commit to complete. Creating and committing an empty transaction is
wasteful, pointless IO and unnecessary rotation of the backup roots.

So use btrfs_attach_transaction_barrier() instead, to avoid creating and
committing empty transactions.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
2ee70ed19c btrfs: avoid starting and committing empty transaction when flushing space
When flushing space and we are in the COMMIT_TRANS state, we join a
transaction with btrfs_join_transaction() and then commit the returned
transaction. However btrfs_join_transaction() starts a new transaction if
there is none currently open, which is pointless since comitting a new,
empty transaction, doesn't achieve anything, it only wastes time, IO and
creates an unnecessary rotation of the backup roots.

So use btrfs_attach_transaction_barrier() to avoid starting a new
transaction. This also waits for any ongoing transaction that is
committing (state >= TRANS_STATE_COMMIT_DOING) to fully complete, and
therefore wait for all the extents that were pinned during the
transaction's lifetime to be unpinned.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
2391245ac2 btrfs: avoid starting new transaction when flushing delayed items and refs
When flushing space we join a transaction to flush delayed items and
delayed references, in order to try to release space. However using
btrfs_join_transaction() not only joins an existing transaction as well
as it starts a new transaction if there is none open. If there is no
transaction open, we don't have neither delayed items nor delayed
references, so creating a new transaction is a waste of time, IO and
creates an unnecessary rotation of the backup roots without gaining any
benefits (including releasing space).

So use btrfs_join_transaction_nostart() when attempting to flush delayed
items and references.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
ed8947bc73 btrfs: merge find_free_dev_extent() and find_free_dev_extent_start()
There is no point in having find_free_dev_extent() because it's just a
simple wrapper around find_free_dev_extent_start() which always passes a
value of 0 for the search_start argument. Since there are no other callers
of find_free_dev_extent_start(), remove find_free_dev_extent() and rename
find_free_dev_extent_start() to find_free_dev_extent(), removing its
search_start argument because it's always 0.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
883647f4b5 btrfs: make find_free_dev_extent() static
The function find_free_dev_extent() is only used within volumes.c, so make
it static and remove its prototype from volumes.h.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
504b1596bd btrfs: make btrfs_cleanup_fs_roots() static
btrfs_cleanup_fs_roots() is not used outside disk-io.c, so make it static,
remove its prototype from disk-io.h and move its definition above the
where it's used in disk-io.c

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
7e3bfd146e btrfs: fail priority metadata ticket with real fs error
At priority_reclaim_metadata_space(), if we were not able to satisfy the
the ticket after going through the various flushing states and we notice
the fs went into an error state, likely due to a transaction abort during
the flushing, set the ticket's error to the error that caused the
transaction abort instead of an unconditional -EROFS.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
a7f8de500e btrfs: return real error when orphan cleanup fails due to a transaction abort
During mount we will call btrfs_orphan_cleanup() to remove any inodes that
were previously deleted (have a link count of 0) but for which we were not
able before to remove their items from the subvolume tree. The removal of
the items will happen by triggering eviction, when we do the final iput()
on them at btrfs_orphan_cleanup(), which will end in the loop at
btrfs_evict_inode() that truncates inode items.

In a dire situation we may have a transaction abort due to -ENOSPC when
attempting to truncate the inode items, and in that case the orphan item
(key type BTRFS_ORPHAN_ITEM_KEY) will remain in the subvolume tree and
when we hit the next iteration of the while loop at btrfs_orphan_cleanup()
we will find the same orphan item as before, and then we will return
-EINVAL from btrfs_orphan_cleanup() through the following if statement:

    if (found_key.offset == last_objectid) {
       btrfs_err(fs_info,
                 "Error removing orphan entry, stopping orphan cleanup");
       ret = -EINVAL;
       goto out;
    }

This makes the mount operation fail with -EINVAL, when it should have been
-ENOSPC. This is confusing because -EINVAL might lead a user into thinking
it provided invalid mount options for example.

An example where this happens:

   $ mount test.img /mnt
   mount: /mnt: wrong fs type, bad option, bad superblock on /dev/loop0, missing codepage or helper program, or other error.

   $ dmesg
   [ 2542.356934] BTRFS: device fsid 977fff75-1181-4d2b-a739-384fa710d16e devid 1 transid 47409973 /dev/loop0 scanned by mount (4459)
   [ 2542.357451] BTRFS info (device loop0): using crc32c (crc32c-intel) checksum algorithm
   [ 2542.357461] BTRFS info (device loop0): disk space caching is enabled
   [ 2542.742287] BTRFS info (device loop0): auto enabling async discard
   [ 2542.764554] BTRFS info (device loop0): checking UUID tree
   [ 2551.743065] ------------[ cut here ]------------
   [ 2551.743068] BTRFS: Transaction aborted (error -28)
   [ 2551.743149] WARNING: CPU: 7 PID: 215 at fs/btrfs/block-group.c:3494 btrfs_write_dirty_block_groups+0x397/0x3d0 [btrfs]
   [ 2551.743311] Modules linked in: btrfs blake2b_generic (...)
   [ 2551.743353] CPU: 7 PID: 215 Comm: kworker/u24:5 Not tainted 6.4.0-rc6-btrfs-next-134+ #1
   [ 2551.743356] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
   [ 2551.743357] Workqueue: events_unbound btrfs_async_reclaim_metadata_space [btrfs]
   [ 2551.743405] RIP: 0010:btrfs_write_dirty_block_groups+0x397/0x3d0 [btrfs]
   [ 2551.743449] Code: 8b 43 0c (...)
   [ 2551.743451] RSP: 0018:ffff982c005a7c40 EFLAGS: 00010286
   [ 2551.743452] RAX: 0000000000000000 RBX: ffff88fc6e44b400 RCX: 0000000000000000
   [ 2551.743453] RDX: 0000000000000002 RSI: ffffffff8dff0878 RDI: 00000000ffffffff
   [ 2551.743454] RBP: ffff88fc51817208 R08: 0000000000000000 R09: ffff982c005a7ae0
   [ 2551.743455] R10: 0000000000000001 R11: 0000000000000001 R12: ffff88fc43d2e570
   [ 2551.743456] R13: ffff88fc43d2e400 R14: ffff88fc8fb08ee0 R15: ffff88fc6e44b530
   [ 2551.743457] FS:  0000000000000000(0000) GS:ffff89035fbc0000(0000) knlGS:0000000000000000
   [ 2551.743458] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   [ 2551.743459] CR2: 00007fa8cdf2f6f4 CR3: 0000000124850003 CR4: 0000000000370ee0
   [ 2551.743462] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
   [ 2551.743463] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
   [ 2551.743464] Call Trace:
   [ 2551.743472]  <TASK>
   [ 2551.743474]  ? __warn+0x80/0x130
   [ 2551.743478]  ? btrfs_write_dirty_block_groups+0x397/0x3d0 [btrfs]
   [ 2551.743520]  ? report_bug+0x1f4/0x200
   [ 2551.743523]  ? handle_bug+0x42/0x70
   [ 2551.743526]  ? exc_invalid_op+0x14/0x70
   [ 2551.743528]  ? asm_exc_invalid_op+0x16/0x20
   [ 2551.743532]  ? btrfs_write_dirty_block_groups+0x397/0x3d0 [btrfs]
   [ 2551.743574]  ? _raw_spin_unlock+0x15/0x30
   [ 2551.743576]  ? btrfs_run_delayed_refs+0x1bd/0x200 [btrfs]
   [ 2551.743609]  commit_cowonly_roots+0x1e9/0x260 [btrfs]
   [ 2551.743652]  btrfs_commit_transaction+0x42e/0xfa0 [btrfs]
   [ 2551.743693]  ? __pfx_autoremove_wake_function+0x10/0x10
   [ 2551.743697]  flush_space+0xf1/0x5d0 [btrfs]
   [ 2551.743743]  ? _raw_spin_unlock+0x15/0x30
   [ 2551.743745]  ? finish_task_switch+0x91/0x2a0
   [ 2551.743748]  ? _raw_spin_unlock+0x15/0x30
   [ 2551.743750]  ? btrfs_get_alloc_profile+0xc9/0x1f0 [btrfs]
   [ 2551.743793]  btrfs_async_reclaim_metadata_space+0xe1/0x230 [btrfs]
   [ 2551.743837]  process_one_work+0x1d9/0x3e0
   [ 2551.743844]  worker_thread+0x4a/0x3b0
   [ 2551.743847]  ? __pfx_worker_thread+0x10/0x10
   [ 2551.743849]  kthread+0xee/0x120
   [ 2551.743852]  ? __pfx_kthread+0x10/0x10
   [ 2551.743854]  ret_from_fork+0x29/0x50
   [ 2551.743860]  </TASK>
   [ 2551.743861] ---[ end trace 0000000000000000 ]---
   [ 2551.743863] BTRFS info (device loop0: state A): dumping space info:
   [ 2551.743866] BTRFS info (device loop0: state A): space_info DATA has 126976 free, is full
   [ 2551.743868] BTRFS info (device loop0: state A): space_info total=13458472960, used=13458137088, pinned=143360, reserved=0, may_use=0, readonly=65536 zone_unusable=0
   [ 2551.743870] BTRFS info (device loop0: state A): space_info METADATA has -51625984 free, is full
   [ 2551.743872] BTRFS info (device loop0: state A): space_info total=771751936, used=770146304, pinned=1605632, reserved=0, may_use=51625984, readonly=0 zone_unusable=0
   [ 2551.743874] BTRFS info (device loop0: state A): space_info SYSTEM has 14663680 free, is not full
   [ 2551.743875] BTRFS info (device loop0: state A): space_info total=14680064, used=16384, pinned=0, reserved=0, may_use=0, readonly=0 zone_unusable=0
   [ 2551.743877] BTRFS info (device loop0: state A): global_block_rsv: size 53231616 reserved 51544064
   [ 2551.743878] BTRFS info (device loop0: state A): trans_block_rsv: size 0 reserved 0
   [ 2551.743879] BTRFS info (device loop0: state A): chunk_block_rsv: size 0 reserved 0
   [ 2551.743880] BTRFS info (device loop0: state A): delayed_block_rsv: size 0 reserved 0
   [ 2551.743881] BTRFS info (device loop0: state A): delayed_refs_rsv: size 786432 reserved 0
   [ 2551.743886] BTRFS: error (device loop0: state A) in btrfs_write_dirty_block_groups:3494: errno=-28 No space left
   [ 2551.743911] BTRFS info (device loop0: state EA): forced readonly
   [ 2551.743951] BTRFS warning (device loop0: state EA): could not allocate space for delete; will truncate on mount
   [ 2551.743962] BTRFS error (device loop0: state EA): Error removing orphan entry, stopping orphan cleanup
   [ 2551.743973] BTRFS warning (device loop0: state EA): Skipping commit of aborted transaction.
   [ 2551.743989] BTRFS error (device loop0: state EA): could not do orphan cleanup -22

So make the btrfs_orphan_cleanup() return the value of BTRFS_FS_ERROR(),
if it's set, and -EINVAL otherwise.

For that same example, after this change, the mount operation fails with
-ENOSPC:

   $ mount test.img /mnt
   mount: /mnt: mount(2) system call failed: No space left on device.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
ae3364e521 btrfs: store the error that turned the fs into error state
Currently when we turn the fs into an error state, typically after a
transaction abort, we don't store the error anywhere, we just set a bit
(BTRFS_FS_STATE_ERROR) at struct btrfs_fs_info::fs_state to signal the
error state.

There are cases where it would be useful to have access to the specific
error in order to provide a more meaningful error to users/applications.
This change adds a member to struct btrfs_fs_info to store the error and
removes the BTRFS_FS_STATE_ERROR bit. When there's no error, the new
member (fs_error) has a value of 0, otherwise its value is a negative
errno value.

Followup changes will make use of this new member.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
1b6948acb8 btrfs: don't steal space from global rsv after a transaction abort
When doing a priority metadata space reclaim, while we are going through
the flush states and running their respective operations, it's possible
that a transaction abort happened, for example when running delayed refs
we hit -ENOSPC or in the critical section of transaction commit we failed
with -ENOSPC or some other error. In these cases a transaction was aborted
and the fs turned into error state. If that happened, then it makes no
sense to steal from the global block reserve and return success to the
caller if the stealing was successful - the caller will later get an
error when attempting to modify the fs. Instead make the ticket fail if
we have the fs in error state and don't attempt to steal from the global
rsv, as it's not only it's pointless, it also simplifies debugging some
-ENOSPC problems.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Filipe Manana
1ff9fee3bd btrfs: print available space across all block groups when dumping space info
When dumping a space info also sum the available space for all block
groups and then print it. This often useful for debugging -ENOSPC
related problems.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Filipe Manana
e50b122b83 btrfs: print available space for a block group when dumping a space info
When dumping a space info, we iterate over all its block groups and then
print their size and the amounts of bytes used, reserved, pinned, etc.
When debugging -ENOSPC problems it's also useful to know how much space
is available (free), so calculate that and print it as well.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Filipe Manana
b92e8f5472 btrfs: print block group super and delalloc bytes when dumping space info
When dumping a space info's block groups, also print the number of bytes
used for super blocks and delalloc. This is often useful for debugging
-ENOSPC problems.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Filipe Manana
4d2024e90d btrfs: print target number of bytes when dumping free space
When dumping free space, with btrfs_dump_free_space(), we pass a bytes
argument in order to count how many free space entries in the block group
have a size greater than or equal to that number of bytes. We then print
how many suitable entries we found, but we don't print the target number
of bytes, we just say "bytes". Change the message to actually print the
number of bytes, which makes debugging -ENOSPC issues a bit easier.

Also sligthly change the odd grammar and terminology: the sentence is
ending with 'is', which doesn't make sense, and the term 'blocks' is
confusing as we are referring to free space entries within the block
group's free space cache.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Filipe Manana
19288951ff btrfs: update comment for btrfs_join_transaction_nostart()
Update the comment for btrfs_join_transaction_nostart() to be more clear
about how it works and how it's different from btrfs_attach_transaction().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Filipe Manana
4490e803e1 btrfs: don't start transaction when joining with TRANS_JOIN_NOSTART
When joining a transaction with TRANS_JOIN_NOSTART, if we don't find a
running transaction we end up creating one. This goes against the purpose
of TRANS_JOIN_NOSTART which is to join a running transaction if its state
is at or below the state TRANS_STATE_COMMIT_START, otherwise return an
-ENOENT error and don't start a new transaction. So fix this to not create
a new transaction if there's no running transaction at or below that
state.

CC: stable@vger.kernel.org # 4.14+
Fixes: a6d155d2e3 ("Btrfs: fix deadlock between fiemap and transaction commits")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Qu Wenruo
096d230165 btrfs: refactor main loop in memmove_extent_buffer()
[BACKGROUND]
Currently memove_extent_buffer() does a loop where it strop at any page
boundary inside [dst_offset, dst_offset + len) or [src_offset,
src_offset + len).

This is mostly allowing us to do copy_pages(), but if we're going to use
folios we will need to handle multi-page (the old behavior) or single
folio (the new optimization).

The current code would be a burden for future changes.

[ENHANCEMENT]
Instead of sticking with copy_pages(), here we utilize the new
__write_extent_buffer() helper to handle the writes.

Unlike the refactoring in memcpy_extent_buffer(), we can not just rely
on the write_extent_buffer() and only handle page boundaries inside src
range.

The function write_extent_buffer() itself is still doing forward
writing, thus it cannot handle the following case: (already in the
extent buffer memory operation tests, cross page overlapping run 2)

	Src	Page boundary
	|///////|
	    |///|////|
	    Dst

In the above case, if we just follow page boundary in the src range, we
have no need to do any split, just one __write_extent_buffer() with
use_memmove = true.

But __write_extent_buffer() would split the dst range into two,
so it first copies the beginning part of the src range into the first half
of the dst range.
After this operation, the beginning of the dst range is already updated,
causing corruption.

So we have to follow the old behavior of handling both page boundaries.

And since we're the last caller of copy_pages(), we can remove it
completely.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Qu Wenruo
13840f3f28 btrfs: refactor main loop in memcpy_extent_buffer()
[BACKGROUND]
Currently memcpy_extent_buffer() does a loop where it would stop at
any page boundary inside [dst_offset, dst_offset + len) or [src_offset,
src_offset + len).

This is mostly allowing us to do copy_pages(), but if we're going to use
folios we will need to handle multi-page (the old behavior) or single
folio (the new optimization).

The current code would be a burden for future changes.

[ENHANCEMENT]
There is a hidden pitfall of the naming memcpy_extent_buffer(), unlike
regular memcpy(), this function can handle overlapping ranges.

So here we extract write_extent_buffer() into a new internal helper,
__write_extent_buffer(), and add a new parameter @use_memmove, to
indicate whether we should use memmove() or regular memcpy().

Now we can go __write_extent_buffer() to handle writing into the dst
range, with proper overlapping detection.

This has a tiny change to the chance of calling memmove().
As the split only happens at the source range page boundaries, the
memcpy/memmove() range would be slightly larger than the old code,
thus slightly increase the chance we call memmove() other than memcopy().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Qu Wenruo
682a0bc557 btrfs: copy all pages at once at the end of btrfs_clone_extent_buffer()
btrfs_clone_extent_buffer() calls copy_page() at each iteration but we
can copy all pages at the end in one go if there were no errors.
This would make later conversion to folios easier.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Qu Wenruo
54948681c2 btrfs: refactor main loop in copy_extent_buffer_full()
[BACKGROUND]
copy_extent_buffer_full() currently does different handling for regular
and subpage cases, for regular cases it does a page by page copying.
For subpage cases, it just copies the content.

This is fine for the page based extent buffer code, but for the incoming
folio conversion, it can be a burden to add a new branch just to handle
all the different combinations (subpage vs regular, one single folio vs
multi pages).

[ENHANCE]
Instead of handling the different combinations, just go one single
handling for all cases, utilizing write_extent_buffer() to do the
copying.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Qu Wenruo
730c374e5b btrfs: use write_extent_buffer() to implement write_extent_buffer_*id()
Helpers write_extent_buffer_chunk_tree_uuid() and
write_extent_buffer_fsid(), they can be implemented by
write_extent_buffer().

These two helpers are not that frequently used, they only get called
during initialization of a new tree block.  There is not much need for
those slightly optimized versions.  And since they can be easily
converted to one write_extent_buffer() call, define them as inline
helpers.

This would make later page/folio switch much easier, as all change only
need to happen in write_extent_buffer().

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:17 +02:00
Qu Wenruo
cb22964f1d btrfs: refactor extent buffer bitmaps operations
[BACKGROUND]
Currently we handle extent bitmaps manually in
extent_buffer_bitmap_set() and extent_buffer_bitmap_clear().

Although with various helpers like eb_bitmap_offset() it's still a little
messy to read.  The code seems to be a copy of bitmap_set(), but with
all the cross-page handling embedded into the code.

[ENHANCEMENT]
This patch would enhance the readability by introducing two helpers:

- memset_extent_buffer()
  To handle the byte aligned range, thus all the cross-page handling is
  done there.

- extent_buffer_get_byte()
  This for the first and the last byte operations, which only need to
  grab one byte, thus no need for any cross-page handling.

So we can split both extent_buffer_bitmap_set() and
extent_buffer_bitmap_clear() into 3 parts:

- Handle the first byte
  If the range fits inside the first byte, we can exit early.

- Handle the byte aligned part
  This is the part which can have cross-page operations, and it would
  be handled by memset_extent_buffer().

- Handle the last byte

This refactoring does not only make the code a little easier to read,
but also makes later folio/page switch much easier, as the switch only
needs to be done inside memset_extent_buffer() and extent_buffer_get_byte().

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Qu Wenruo
5864f1da6b btrfs: tests: add self tests for extent buffer memory operations
The new self tests would populate a memory range with random bytes, then
copy it to the extent buffer, so that we can verify if the extent buffer
memory operation and memmove()/memcopy() are resulting the same
contents.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Qu Wenruo
257deed2a9 btrfs: tests: enhance extent buffer bitmap tests
Enhance extent bitmap tests for the following aspects:

- Remove unnecessary @len from __test_eb_bitmaps()
  We can fetch the length from extent buffer

- Explicitly distinguish bit and byte length
  Now every start/len inside bitmap tests would have either "byte_" or
  "bit_" prefix to make it more explicit.

- Better error reporting

  If we have mismatch bits, the error report would dump the following
  contents:

  * start bytenr
  * bit number
  * the full byte from bitmap
  * the full byte from the extent

  This is to save developers time so obvious problem can be found
  immediately

- Extract bitmap set/clear and check operation into two helpers
  This is to save some code lines, as we will have more tests to do.

- Add new tests

  The following tests are added, mostly for the incoming extent bitmap
  accessor refactoring:

  * Set bits inside the same byte
  * Clear bits inside the same byte
  * Cross byte boundary set
  * Cross byte boundary clear
  * Cross multi-byte boundary set
  * Cross multi-byte boundary clear

  Those new tests have already saved my backend for the incoming extent
  buffer bitmap refactoring.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Josef Bacik
b9d97cff25 btrfs: move comments to btrfs_loop_type definition
Some of these loop types aren't described, and they should be with the
definitions to make it easier to tell what each of them do.

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Anand Jain
7f9879eb60 btrfs: print name and pid when device scanning processes race
There is a race between systemd and mount, as both of them try to register
the device in the kernel. When systemd loses the race, it prints the
following message:

  BTRFS error: device /dev/sdb7 belongs to fsid 1b3bacbf-14db-49c9-a3ef-547998aacc4e, and the fs is already mounted.

The 'btrfs dev scan' registers one device at a time, so there is no way
for the mount thread to wait in the kernel for all the devices to have
registered as it won't know if all the devices are discovered.

For now, improve the error log by printing the command name and process
ID along with the error message.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Christoph Hellwig
256b0cf90d btrfs: fix zoned handling in submit_uncompressed_range
For zoned file systems we need to use run_delalloc_zoned to submit
writeback, as we need to write out partial allocations when running into
zone active limits.

submit_uncompressed_range currently always calls cow_file_range to
allocate blocks and thus misses the active zone limits handling.  Fix
this by passing the pages_dirty argument to run_delalloc_zoned and always
using it from submit_uncompressed_range as it does the right thing for
zoned and non-zoned file systems.

To account for the fact that run_delalloc_zoned is now also used for
non-zoned file systems rename it to run_delalloc_cow, and add comment
describing it.

Fixes: 42c0110009 ("btrfs: zoned: introduce dedicated data write path for zoned filesystems")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Christoph Hellwig
778b878543 btrfs: don't redirty locked_page in run_delalloc_zoned
extent_write_locked_range currently expects that either all or no
pages are dirty when it is called.  Bur run_delalloc_zoned is called
directly in the writepages path, and has the dirty bit cleared only
for locked_page and which the extent_write_cache_pages currently
operates.  It currently works around this by redirtying locked_page,
but that is a bit inefficient and cumbersome.  Pass a locked_page
argument to run_delalloc_zoned so that clearing the dirty bit can
be skipped on just that page.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Christoph Hellwig
6e144bf16b btrfs: refactor the zoned device handling in cow_file_range
Handling of the done_offset to cow_file_range is a bit confusing, as
it is not updated at all when the function succeeds, and the -EAGAIN
status is used bother for the case where we need to wait for a zone
finish and the one where the allocation was partially successful.

Change the calling convention so that done_offset is always updated,
and 0 is returned if some allocation was successful (partial allocation
can still only happen for zoned devices), and waiting for a zone
finish is done internally in cow_file_range instead of the caller.

Also write a comment explaining the logic.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:16 +02:00
Christoph Hellwig
44962ca37c btrfs: don't redirty pages in compress_file_range
compress_file_range needs to clear the dirty bit before handing off work
to the compression worker threads to prevent processes coming in through
mmap and changing the file contents while the compression is accessing
the data (See commit 4adaa61102 ("Btrfs: fix race between mmap writes
and compression").

But when compress_file_range decides to not compress the data, it falls
back to submit_uncompressed_range which uses extent_write_locked_range
to write the uncompressed data.  extent_write_locked_range currently
expects all pages to be marked dirty so that it can clear the dirty
bit itself, and thus compress_file_range has to redirty the page range.

Redirtying the page range is rather inefficient and also pointless,
so instead pass a pages_dirty parameter to extent_write_locked_range
and skip the redirty game entirely.

Note that compress_file_range was even redirtying the locked_page twice
given that extent_range_clear_dirty_for_io already redirties all pages
in the range, which must include locked_page if there is one.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
f778b6b8e0 btrfs: share the code to free the page array in compress_file_range
compress_file_range has two code blocks to free the page array for the
compressed data.  Share the code using a goto label.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
184aa1ffa5 btrfs: use a separate label for the incompressible case in compress_file_range
compress_file_range can fail to compress either because of resource or
alignment constraints or because the data is incompressible.  In the latter
case the inode is marked so that compression isn't tried again.  Currently
that check is based on the condition that the pages array has been allocated
which is rather cryptic.  Use a separate label to clearly distinguish this
case.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
6a7167bf9c btrfs: further simplify the compress or not logic in compress_file_range
Currently the logic whether to compress or not in compress_file_range is
a bit convoluted because it tries to share code for creating inline
extents for the compressible [1] path and the bail to uncompressed path.

But the latter isn't needed at all, because cow_file_range as called by
submit_uncompressed_range will already create inline extents as needed,
so there is no need to have special handling for it if we can live with
the fact that it will be called a bit later in the ->ordered_func of the
workqueue instead of right now.

[1] there is undocumented logic that creates an uncompressed inline
extent outside of the shall not compress logic if total_in is too small.
This logic isn't explained in comments or any commit log I could find,
so I've preserved it.  Documentation explaining it would be appreciated
if anyone understands this code.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
e94e54e89b btrfs: streamline compress_file_range
Reorder compress_file_range so that the main compression flow happens
straight line and not in branches.  To do this ensure that pages is
always zeroed before a page allocation happens, which allows the
cleanup_and_bail_uncompressed label to clean up the page allocations
as needed.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
00d31d1766 btrfs: merge submit_compressed_extents and async_cow_submit
The code in submit_compressed_extents just loops over the async_extents,
and doesn't need to be conditional on an inode being present, as there
won't be any async_extent in the list if we created and inline extent.
Merge the two functions to simplify the logic.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
c15d8cf295 btrfs: merge async_cow_start and compress_file_range
There is no good reason to have the simple async_cow_start wrapper,
merge the argument conversion into the main compress_file_range function.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
3134508e47 btrfs: don't clear async_chunk->inode in async_cow_start
Now that the ->inode check isn't needed in submit_compressed_extents
any more, there is no reason to clear the field early.  Always keep
the inode around until the work item is finished and remove the special
casing, and the counting of compressed extents in compress_file_range.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
6758346808 btrfs: clean up the check for uncompressed ranges in submit_one_async_extent
Instead of checking for a NULL !pages and explaining this with a cryptic
comment, just check the compression type for BTRFS_COMPRESS_NONE to make
the check self-explanatory.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:15 +02:00
Christoph Hellwig
c56cbe9059 btrfs: reduce the number of arguments to btrfs_run_delalloc_range
Instead of a separate page_started argument that tells the callers that
btrfs_run_delalloc_range already started writeback by itself, overload
the return value with a positive 1 in additio to 0 and a negative error
code to indicate that is has already started writeback, and remove the
nr_written argument as that caller can calculate it directly based on
the range, and in fact already does so for the case where writeback
wasn't started yet.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
2c73162d64 btrfs: improve the delalloc_to_write calculation in writepage_delalloc
Currently writepage_delalloc adds to delalloc_to_write in every loop
operation.  That is not only more work than doing it once after the
loop, but can also over-increment the counter due to rounding errors
when a new loop iteration starts with an offset into a page.

Add a new page_start variable instead of recaculation that value over
and over, move the delalloc_to_write calculation out of the loop, use
the DIV_ROUND_UP helper instead of open coding it and remove the pointless
found local variable.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
0835d1e66e btrfs: remove the return value from extent_write_locked_range
The return value from extent_write_locked_range is ignored, and that's
fine because the error reporting happens through the mapping and
ordered_extent.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
ff20d6a4a9 btrfs: remove the return value from submit_uncompressed_range
The return value from submit_uncompressed_range is ignored, and that's
fine because the error reporting happens through the mapping and
ordered_extent.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
84f262f009 btrfs: reduce debug spam from submit_compressed_extents
Move the printk that is supposed to help to debug failures in
submit_one_async_extent into submit_one_async_extent and make it
coniditonal on actually having an error condition instead of spamming
the log unconditionally.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
9783e4deed btrfs: remove end_extent_writepage
end_extent_writepage is a small helper that combines a call to
btrfs_mark_ordered_io_finished with conditional error-only calls to
btrfs_page_clear_uptodate and mapping_set_error with a somewhat
unfortunate calling convention that passes and inclusive end instead
of the len expected by the underlying functions.

Remove end_extent_writepage and open code it in the 4 callers. Out
of those two already are error-only and thus don't need the extra
conditional, and one already has the mapping_set_error, so a duplicate
call can be avoided.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
6648cedd86 btrfs: remove btrfs_writepage_endio_finish_ordered
btrfs_writepage_endio_finish_ordered is a small wrapper around
btrfs_mark_ordered_io_finished that just changs the argument passing
slightly, and adds a tracepoint.

Move the tracpoint to btrfs_mark_ordered_io_finished, which means
it now also covers the error handling in btrfs_cleanup_ordered_extent
and switch all callers to just call btrfs_mark_ordered_io_finished
directly.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
ef4e88e6a5 btrfs: split page locking out of __process_pages_contig
There is a lot of complexity in __process_pages_contig to deal with the
PAGE_LOCK case that can return an error unlike all the other actions.

Open code the page iteration for page locking in lock_delalloc_pages and
remove all the now unused code from __process_pages_contig.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
53ffb30a78 btrfs: don't create inline extents in fallback_to_cow
For NOCOW files, run_delalloc_nocow can still fall back to COW
allocations when required and calls to fallback_to_cow helper for
that.  For such an allocation we can have multiple ordered_extents
for existing extents that NOCOW overwrites and new allocations that
fallback_to_cow creates.  If one of the new extents is an inline
extent, the writepages could would have to avoid normal page writeback
for them as indicated by the page_started return argument, which
run_delalloc_nocow can't return.   Fix this by never creating inline
extents from fallback_to_cow.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Christoph Hellwig
ba9145add5 btrfs: pass a flags argument to cow_file_range
The int used as bool unlock is not a very good way to describe the
behavior, and the next patch will have to add another behavior modifier.
We'll do that by two bool parameters instead of adding bit flags.  Now
specifies that the pages should always be kept locked.  This is the
inverse of the old unlock argument.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ switch flags to bool ]
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:14 +02:00
Boris Burkov
a649684967 btrfs: fix start transaction qgroup rsv double free
btrfs_start_transaction reserves metadata space of the PERTRANS type
before it identifies a transaction to start/join. This allows flushing
when reserving that space without a deadlock. However, it results in a
race which temporarily breaks qgroup rsv accounting.

T1                                              T2
start_transaction
do_stuff
                                            start_transaction
                                                qgroup_reserve_meta_pertrans
commit_transaction
    qgroup_free_meta_all_pertrans
                                            hit an error starting txn
                                            goto reserve_fail
                                            qgroup_free_meta_pertrans (already freed!)

The basic issue is that there is nothing preventing another commit from
committing before start_transaction finishes (in fact sometimes we
intentionally wait for it) so any error path that frees the reserve is
at risk of this race.

While this exact space was getting freed anyway, and it's not a huge
deal to double free it (just a warning, the free code catches this), it
can result in incorrectly freeing some other pertrans reservation in
this same reservation, which could then lead to spuriously granting
reservations we might not have the space for. Therefore, I do believe it
is worth fixing.

To fix it, use the existing prealloc->pertrans conversion mechanism.
When we first reserve the space, we reserve prealloc space and only when
we are sure we have a transaction do we convert it to pertrans. This way
any racing commits do not blow away our reservation, but we still get a
pertrans reservation that is freed when _this_ transaction gets committed.

This issue can be reproduced by running generic/269 with either qgroups
or squotas enabled via mkfs on the scratch device.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
CC: stable@vger.kernel.org # 5.10+
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Boris Burkov
e28b02118b btrfs: free qgroup rsv on io failure
If we do a write whose bio suffers an error, we will never reclaim the
qgroup reserved space for it. We allocate the space in the write_iter
codepath, then release the reservation as we allocate the ordered
extent, but we only create a delayed ref if the ordered extent finishes.
If it has an error, we simply leak the rsv. This is apparent in running
any error injecting (dmerror) fstests like btrfs/146 or btrfs/160. Such
tests fail due to dmesg on umount complaining about the leaked qgroup
data space.

When we clean up other aspects of space on failed ordered_extents, also
free the qgroup rsv.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
CC: stable@vger.kernel.org # 5.10+
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Goldwyn Rodrigues
75d305c55b btrfs: remove duplicate free_async_extent_pages() on reservation error
While performing compressed writes, if the extent reservation fails, the
async extent pages are first freed in the error check for return value
ret, and then again at out_free label.

Remove the first call to free_async_extent_pages().

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>
2023-08-21 14:52:13 +02:00
Qu Wenruo
52ea5bfbfa btrfs: move eb subpage preallocation out of the loop
Initially we preallocate btrfs_subpage structure in the main loop of
alloc_extent_buffer().

But later commit fbca46eb46 ("btrfs: make nodesize >= PAGE_SIZE case
to reuse the non-subpage routine") has made sure we only go subpage
routine if our nodesize is smaller than PAGE_SIZE.

This means for that case, we only need to allocate the subpage structure
once anyway.

So this patch would make the preallocation out of the main loop.  This
would slightly reduce the workload when we hold the page lock, and make
code a little easier to read.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Christoph Hellwig
b2cc440058 btrfs: simplify the no-bioc fast path condition in btrfs_map_block
nr_alloc_stripes can't be one if we are writing to a replacement device,
as it is incremented for that case right above.  Remove the duplicate
checks.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Qu Wenruo
17353a3447 btrfs: scrub: remove unused btrfs_path in scrub_simple_mirror()
The @path in scrub_simple_mirror() is no longer utilized after commit
e02ee89baa ("btrfs: scrub: switch scrub_simple_mirror() to scrub_stripe
infrastructure").

Before that commit, we call find_first_extent_item() directly, which
needs a path and that path can be reused.  But after that switch commit,
the extent search is done inside queue_scrub_stripe(), which will no
longer accept a path from outside.

So the @path variable can be safely removed.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ remove the stale comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Minjie Du
7b365a2a3d btrfs: use folio_next_index() helper in extent_write_cache_pages
Simplify code pattern of 'folio->index + folio_nr_pages(folio)' by using
the existing helper folio_next_index().

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Minjie Du <duminjie@vivo.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
David Sterba
98efb4eb31 btrfs: use helper sizeof_field in struct accessors
There's a helper for obtaining size of a struct member, we can use it
instead of open coding the pointer magic.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Qu Wenruo
16c3a47648 btrfs: deprecate integrity checker feature
The integrity checker feature needs to be enabled at compile time
(BTRFS_FS_CHECK_INTEGRITY) and then enabled by mount options check_int*.

Although it provides some unique features which can not be provided by
any other sanity checks like tree-checker, it does not only have high
CPU and memory overhead, but is also a maintenance burden.

For example, it's the only caller of btrfs_map_block() with
@need_raid_map = 0.

Considering most btrfs developers are not even testing this feature, I'm
here to propose deprecation of this feature.

For now only warning messages will be printed, the feature itself would
still work.

Removal time has been set to 6.7 release.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Filipe Manana
98b5a8fd2a btrfs: move btrfs_free_excluded_extents() into block-group.c
The function btrfs_free_excluded_extents() is only used by block-group.c,
so move it into block-group.c and make it static. Also removed unnecessary
variables that are used only once.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Filipe Manana
b1c8f527fe btrfs: open code trivial btrfs_add_excluded_extent()
The code for btrfs_add_excluded_extent() is trivial, it's just a
set_extent_bit() call. However it's defined in extent-tree.c but it is
only used (twice) in block-group.c. So open code it in block-group.c,
reducing the need to export a trivial function.

Also since the only caller btrfs_add_excluded_extent() is prepared to
deal with errors, stop ignoring errors from the set_extent_bit() call.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:13 +02:00
Filipe Manana
e5860f8207 btrfs: make find_first_extent_bit() return a boolean
Currently find_first_extent_bit() returns a 0 if it found a range in the
given io tree and 1 if it didn't find any. There's no need to return any
errors, so make the return value a boolean and invert the logic to make
more sense: return true if it found a range and false if it didn't find
any range.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Filipe Manana
46d81ebd4a btrfs: make btrfs_destroy_pinned_extent() return void
Currently btrfs_destroy_pinned_extent() is always returning 0 no matter
what and its caller ignores its return value (as well everything up in
the call chain). This is because this is called in the transaction abort
path, where we can't even deal with any errors since we are in a critical
situation already and cleanup of resources is done in a best effort
fashion.

So make btrfs_destroy_pinned_extent() return void.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Filipe Manana
aec5716c3e btrfs: make btrfs_destroy_marked_extents() return void
Currently btrfs_destroy_marked_extents() is returning the value of the
last call to find_first_extent_bit(), which returns a value of 1 meaning
no more ranges found the dirty pages io tree. This value is useless to the
single caller of btrfs_destroy_marked_extents(), which ignores any return
value from btrfs_destroy_marked_extents(). This is because it's only used
in the transaction abort path, where we can't even deal with any errors
since we are in a critical situation already and cleanup of resources is
done in a best effort fashion.

So make btrfs_destroy_marked_extents() return void.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Filipe Manana
3b9f0995d8 btrfs: rename add_new_free_space() to btrfs_add_new_free_space()
Since add_new_free_space() is exported, used outside block-group.c, rename
it to include the 'btrfs_' prefix.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Filipe Manana
28f6089490 btrfs: update documentation for add_new_free_space()
The documentation for add_new_free_space() is stale and no longer correct:

1) It's no longer used only when caching a block group. It's also called
   when creating a block group (btrfs_make_block_group()), when reading
   a block group at mount time (read_one_block_group()) and when reading
   the free space tree for a block group (typically the first time we
   attempt to allocate from the block group);

2) It has nothing to do with pinned extents. It only deals with the
   excluded extents io tree, which is used to track the locations of
   super blocks in order to make sure we never add the location of a
   super block to the free space cache of a block group.

So update the documention and also add a description of the arguments
and return values.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Qu Wenruo
dbb6ecb328 btrfs: tracepoints: simplify raid56 events
After commit 6bfd0133be ("btrfs: raid56: switch scrub path to use a
single function"), the raid56 implementation no longer uses different
endio functions for RMW/recover/scrub.

All read operations end in submit_read_wait_bio_list(), while all write
operations end in submit_write_bios().  This means quite some trace
events are out-of-date and no longer utilized.

This patch would unify the trace events into just two:

- trace_raid56_read()
  Replaces trace_raid56_read_partial(), trace_raid56_scrub_read() and
  trace_raid56_scrub_read_recover().

- trace_raid56_write()
  Replaces trace_raid56_write_stripe() and
  trace_raid56_scrub_write_stripe().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Anand Jain
070bb0011c btrfs: sysfs: show if ACL support has been compiled in
ACL support depends on the compile-time configuration option
CONFIG_BTRFS_FS_POSIX_ACL. Prior to mounting a btrfs filesystem, it is not
possible to determine whether ACL support has been compiled in. To address
this, add a sysfs interface, /sys/fs/btrfs/features/acl, and check for ACL
support in the system's btrfs.

  To determine ACL support:

  Return 0 indicates ACL is not supported:
    $ cat /sys/fs/btrfs/features/acl
    0

  Return 1 indicates ACL is supported:
    $ cat /sys/fs/btrfs/features/acl
    1

IMO, this is a better approach, so that we also know if kernel is older.

  On an older kernel
    $ ls /sys/fs/btrfs/features/acl
    ls: cannot access '/sys/fs/btrfs/features/acl': No such file or directory

    mount a btrfs filesystem
    $ cat /proc/self/mounts | grep btrfs | grep -q noacl
    $ echo $?
    0

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Qu Wenruo
3a3c7a7f65 btrfs: raid56: remove unused BTRFS_RBIO_REBUILD_MISSING
Commit aca43fe839 ("btrfs: remove unused raid56 functions which were
dedicated for scrub") removed the special handling of RAID56 scrub for
missing device.

As scrub goes full mirror_num based recovery, that means if it hits a
missing device in RAID56, it would just try the next mirror, which would
go through the BTRFS_RBIO_READ_REBUILD operation.

This means there is no longer any use of BTRFS_RBIO_REBUILD_MISSING
operation and we can safely remove it.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Qu Wenruo
ed3764f726 btrfs: add comments for btrfs_map_block()
The function btrfs_map_block() is a critical part of the btrfs storage
layer, which handles mapping of logical ranges to physical ranges.

Thus it's better to have some basic explanation, especially on the
following points:

- Segment split by various boundaries
  As a continuous logical range may be split into different segments,
  due to various factors like zones and RAID0/5/6/10 boundaries.

- The meaning of @mirror_num

- The possible single stripe optimization

- One deprecated parameter @need_raid_map
  Just explicitly mark it deprecated so we're aware of the problem.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Colin Ian King
966de47ff0 btrfs: remove redundant initialization of variables in log_new_ancestors
The variables leaf and slot are initialized when declared but the values
assigned to them are never read as they are being re-assigned later on.
The initializations are redundant and can be removed. Cleans up clang
scan build warnings:

fs/btrfs/tree-log.c:6797:25: warning: Value stored to 'leaf' during its
initialization is never read [deadcode.DeadStores]
fs/btrfs/tree-log.c:6798:7: warning: Value stored to 'slot' during its
initialization is never read [deadcode.DeadStores]

It's been there since b8aa330d2a ("Btrfs: improve performance on fsync
of files with multiple hardlinks") without any usage so it's safe to be
removed.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Colin Ian King
cf4ac2b904 btrfs: scrub: remove redundant division of stripe_nr
Variable stripe_nr is being divided by map->num_stripes however the
result is never read. The division and assignment are redundant and
can be removed. Cleans up clang scan build warning:

fs/btrfs/scrub.c:1264:3: warning: Value stored to 'stripe_nr' is
never read [deadcode.DeadStores]

The code is a leftover from 6ded22c1bf ("btrfs: reduce div64 calls by
limiting the number of stripes of a chunk to u32") that converted div64
to normal division, it's the same but previous version did not trigger a
warning.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:11 +02:00
Julia Lawall
07a3bb95ea btrfs: zoned: use vcalloc instead of for vzalloc in btrfs_get_dev_zone_info
Use vcalloc that checks potential multiplication overflows.  The changes
were done using Coccinelle semantic patch.

Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:11 +02:00
Linus Torvalds
12e6ccedb3 for-6.5-rc6-tag
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Merge tag 'for-6.5-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - fix infinite loop in readdir(), could happen in a big directory when
   files get renamed during enumeration

 - fix extent map handling of skipped pinned ranges

 - fix a corner case when handling ordered extent length

 - fix a potential crash when balance cancel races with pause

 - verify correct uuid when starting scrub or device replace

* tag 'for-6.5-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix incorrect splitting in btrfs_drop_extent_map_range
  btrfs: fix BUG_ON condition in btrfs_cancel_balance
  btrfs: only subtract from len_to_oe_boundary when it is tracking an extent
  btrfs: fix replace/scrub failure with metadata_uuid
  btrfs: fix infinite directory reads
2023-08-19 17:57:07 +02:00
Josef Bacik
c962098ca4 btrfs: fix incorrect splitting in btrfs_drop_extent_map_range
In production we were seeing a variety of WARN_ON()'s in the extent_map
code, specifically in btrfs_drop_extent_map_range() when we have to call
add_extent_mapping() for our second split.

Consider the following extent map layout

	PINNED
	[0 16K)  [32K, 48K)

and then we call btrfs_drop_extent_map_range for [0, 36K), with
skip_pinned == true.  The initial loop will have

	start = 0
	end = 36K
	len = 36K

we will find the [0, 16k) extent, but since we are pinned we will skip
it, which has this code

	start = em_end;
	if (end != (u64)-1)
		len = start + len - em_end;

em_end here is 16K, so now the values are

	start = 16K
	len = 16K + 36K - 16K = 36K

len should instead be 20K.  This is a problem when we find the next
extent at [32K, 48K), we need to split this extent to leave [36K, 48k),
however the code for the split looks like this

	split->start = start + len;
	split->len = em_end - (start + len);

In this case we have

	em_end = 48K
	split->start = 16K + 36K       // this should be 16K + 20K
	split->len = 48K - (16K + 36K) // this overflows as 16K + 36K is 52K

and now we have an invalid extent_map in the tree that potentially
overlaps other entries in the extent map.  Even in the non-overlapping
case we will have split->start set improperly, which will cause problems
with any block related calculations.

We don't actually need len in this loop, we can simply use end as our
end point, and only adjust start up when we find a pinned extent we need
to skip.

Adjust the logic to do this, which keeps us from inserting an invalid
extent map.

We only skip_pinned in the relocation case, so this is relatively rare,
except in the case where you are running relocation a lot, which can
happen with auto relocation on.

Fixes: 55ef689900 ("Btrfs: Fix btrfs_drop_extent_cache for skip pinned case")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-18 14:38:10 +02:00
xiaoshoukui
29eefa6d0d btrfs: fix BUG_ON condition in btrfs_cancel_balance
Pausing and canceling balance can race to interrupt balance lead to BUG_ON
panic in btrfs_cancel_balance. The BUG_ON condition in btrfs_cancel_balance
does not take this race scenario into account.

However, the race condition has no other side effects. We can fix that.

Reproducing it with panic trace like this:

  kernel BUG at fs/btrfs/volumes.c:4618!
  RIP: 0010:btrfs_cancel_balance+0x5cf/0x6a0
  Call Trace:
   <TASK>
   ? do_nanosleep+0x60/0x120
   ? hrtimer_nanosleep+0xb7/0x1a0
   ? sched_core_clone_cookie+0x70/0x70
   btrfs_ioctl_balance_ctl+0x55/0x70
   btrfs_ioctl+0xa46/0xd20
   __x64_sys_ioctl+0x7d/0xa0
   do_syscall_64+0x38/0x80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd

  Race scenario as follows:
  > mutex_unlock(&fs_info->balance_mutex);
  > --------------------
  > .......issue pause and cancel req in another thread
  > --------------------
  > ret = __btrfs_balance(fs_info);
  >
  > mutex_lock(&fs_info->balance_mutex);
  > if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
  >         btrfs_info(fs_info, "balance: paused");
  >         btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
  > }

CC: stable@vger.kernel.org # 4.19+
Signed-off-by: xiaoshoukui <xiaoshoukui@ruijie.com.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-17 15:27:45 +02:00
Chris Mason
09c3717c3a btrfs: only subtract from len_to_oe_boundary when it is tracking an extent
bio_ctrl->len_to_oe_boundary is used to make sure we stay inside a zone
as we submit bios for writes.  Every time we add a page to the bio, we
decrement those bytes from len_to_oe_boundary, and then we submit the
bio if we happen to hit zero.

Most of the time, len_to_oe_boundary gets set to U32_MAX.
submit_extent_page() adds pages into our bio, and the size of the bio
ends up limited by:

- Are we contiguous on disk?
- Does bio_add_page() allow us to stuff more in?
- is len_to_oe_boundary > 0?

The len_to_oe_boundary math starts with U32_MAX, which isn't page or
sector aligned, and subtracts from it until it hits zero.  In the
non-zoned case, the last IO we submit before we hit zero is going to be
unaligned, triggering BUGs.

This is hard to trigger because bio_add_page() isn't going to make a bio
of U32_MAX size unless you give it a perfect set of pages and fully
contiguous extents on disk.  We can hit it pretty reliably while making
large swapfiles during provisioning because the machine is freshly
booted, mostly idle, and the disk is freshly formatted.  It's also
possible to trigger with reads when read_ahead_kb is set to 4GB.

The code has been clean up and shifted around a few times, but this flaw
has been lurking since the counter was added.  I think the commit
24e6c80822 ("btrfs: simplify main loop in submit_extent_page") ended
up exposing the bug.

The fix used here is to skip doing math on len_to_oe_boundary unless
we've changed it from the default U32_MAX value.  bio_add_page() is the
real limit we want, and there's no reason to do extra math when block
layer is doing it for us.

Sample reproducer, note you'll need to change the path to the bdi and
device:

  SUBVOL=/btrfs/swapvol
  SWAPFILE=$SUBVOL/swapfile
  SZMB=8192

  mkfs.btrfs -f /dev/vdb
  mount /dev/vdb /btrfs

  btrfs subvol create $SUBVOL
  chattr +C $SUBVOL
  dd if=/dev/zero of=$SWAPFILE bs=1M count=$SZMB
  sync

  echo 4 > /proc/sys/vm/drop_caches

  echo 4194304 > /sys/class/bdi/btrfs-2/read_ahead_kb

  while true; do
	  echo 1 > /proc/sys/vm/drop_caches
	  echo 1 > /proc/sys/vm/drop_caches
	  dd of=/dev/zero if=$SWAPFILE bs=4096M count=2 iflag=fullblock
  done

Fixes: 24e6c80822 ("btrfs: simplify main loop in submit_extent_page")
CC: stable@vger.kernel.org # 6.4+
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-17 15:27:35 +02:00
Anand Jain
b471965fdb btrfs: fix replace/scrub failure with metadata_uuid
Fstests with POST_MKFS_CMD="btrfstune -m" (as in the mailing list)
reported a few of the test cases failing.

The failure scenario can be summarized and simplified as follows:

  $ mkfs.btrfs -fq -draid1 -mraid1 /dev/sdb1 /dev/sdb2 :0
  $ btrfstune -m /dev/sdb1 :0
  $ wipefs -a /dev/sdb1 :0
  $ mount -o degraded /dev/sdb2 /btrfs :0
  $ btrfs replace start -B -f -r 1 /dev/sdb1 /btrfs :1
    STDERR:
    ERROR: ioctl(DEV_REPLACE_START) failed on "/btrfs": Input/output error

  [11290.583502] BTRFS warning (device sdb2): tree block 22036480 mirror 2 has bad fsid, has 99835c32-49f0-4668-9e66-dc277a96b4a6 want da40350c-33ac-4872-92a8-4948ed8c04d0
  [11290.586580] BTRFS error (device sdb2): unable to fix up (regular) error at logical 22020096 on dev /dev/sdb8 physical 1048576

As above, the replace is failing because we are verifying the header with
fs_devices::fsid instead of fs_devices::metadata_uuid, despite the
metadata_uuid actually being present.

To fix this, use fs_devices::metadata_uuid. We copy fsid into
fs_devices::metadata_uuid if there is no metadata_uuid, so its fine.

Fixes: a3ddbaebc7 ("btrfs: scrub: introduce a helper to verify one metadata block")
CC: stable@vger.kernel.org # 6.4+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-17 15:26:39 +02:00
Scott Mayhew
270d73e650 smb: client: fix null auth
Commit abdb1742a3 removed code that clears ctx->username when sec=none, so attempting
to mount with '-o sec=none' now fails with -EACCES.  Fix it by adding that logic to the
parsing of the 'sec' option, as well as checking if the mount is using null auth before
setting the username when parsing the 'user' option.

Fixes: abdb1742a3 ("cifs: get rid of mount options string parsing")
Cc: stable@vger.kernel.org
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-16 00:26:07 -05:00
Linus Torvalds
2d7b8c6b90 three smb client fixes, all for stable
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Merge tag '6.5-rc6-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull smb client fixes from Steve French:
 "Three smb client fixes, all for stable:

   - fix for oops in unmount race with lease break of deferred close

   - debugging improvement for reconnect

   - fix for fscache deadlock (folio_wait_bit_common hang)"

* tag '6.5-rc6-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: display network namespace in debug information
  cifs: Release folio lock on fscache read hit.
  cifs: fix potential oops in cifs_oplock_break
2023-08-15 20:00:40 +00:00
Filipe Manana
9b378f6ad4 btrfs: fix infinite directory reads
The readdir implementation currently processes always up to the last index
it finds. This however can result in an infinite loop if the directory has
a large number of entries such that they won't all fit in the given buffer
passed to the readdir callback, that is, dir_emit() returns a non-zero
value. Because in that case readdir() will be called again and if in the
meanwhile new directory entries were added and we still can't put all the
remaining entries in the buffer, we keep repeating this over and over.

The following C program and test script reproduce the problem:

  $ cat /mnt/readdir_prog.c
  #include <sys/types.h>
  #include <dirent.h>
  #include <stdio.h>

  int main(int argc, char *argv[])
  {
    DIR *dir = opendir(".");
    struct dirent *dd;

    while ((dd = readdir(dir))) {
      printf("%s\n", dd->d_name);
      rename(dd->d_name, "TEMPFILE");
      rename("TEMPFILE", dd->d_name);
    }
    closedir(dir);
  }

  $ gcc -o /mnt/readdir_prog /mnt/readdir_prog.c

  $ cat test.sh
  #!/bin/bash

  DEV=/dev/sdi
  MNT=/mnt/sdi

  mkfs.btrfs -f $DEV &> /dev/null
  #mkfs.xfs -f $DEV &> /dev/null
  #mkfs.ext4 -F $DEV &> /dev/null

  mount $DEV $MNT

  mkdir $MNT/testdir
  for ((i = 1; i <= 2000; i++)); do
      echo -n > $MNT/testdir/file_$i
  done

  cd $MNT/testdir
  /mnt/readdir_prog

  cd /mnt

  umount $MNT

This behaviour is surprising to applications and it's unlike ext4, xfs,
tmpfs, vfat and other filesystems, which always finish. In this case where
new entries were added due to renames, some file names may be reported
more than once, but this varies according to each filesystem - for example
ext4 never reported the same file more than once while xfs reports the
first 13 file names twice.

So change our readdir implementation to track the last index number when
opendir() is called and then make readdir() never process beyond that
index number. This gives the same behaviour as ext4.

Reported-by: Rob Landley <rob@landley.net>
Link: https://lore.kernel.org/linux-btrfs/2c8c55ec-04c6-e0dc-9c5c-8c7924778c35@landley.net/
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217681
CC: stable@vger.kernel.org # 6.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-14 16:17:37 +02:00
Steve French
7b38f6ddc9 smb3: display network namespace in debug information
We recently had problems where a network namespace was deleted
causing hard to debug reconnect problems.  To help deal with
configuration issues like this it is useful to dump the network
namespace to better debug what happened.

So add this to information displayed in /proc/fs/cifs/DebugData for
the server (and channels if mounted with multichannel). For example:

   Local Users To Server: 1 SecMode: 0x1 Req On Wire: 0 Net namespace: 4026531840

This can be easily compared with what is displayed for the
processes on the system. For example /proc/1/ns/net in this case
showed the same thing (see below), and we can see that the namespace
is still valid in this example.

   'net:[4026531840]'

Cc: stable@vger.kernel.org
Acked-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-14 08:41:29 -05:00
Russell Harmon via samba-technical
69513dd669 cifs: Release folio lock on fscache read hit.
Under the current code, when cifs_readpage_worker is called, the call
contract is that the callee should unlock the page. This is documented
in the read_folio section of Documentation/filesystems/vfs.rst as:

> The filesystem should unlock the folio once the read has completed,
> whether it was successful or not.

Without this change, when fscache is in use and cache hit occurs during
a read, the page lock is leaked, producing the following stack on
subsequent reads (via mmap) to the page:

$ cat /proc/3890/task/12864/stack
[<0>] folio_wait_bit_common+0x124/0x350
[<0>] filemap_read_folio+0xad/0xf0
[<0>] filemap_fault+0x8b1/0xab0
[<0>] __do_fault+0x39/0x150
[<0>] do_fault+0x25c/0x3e0
[<0>] __handle_mm_fault+0x6ca/0xc70
[<0>] handle_mm_fault+0xe9/0x350
[<0>] do_user_addr_fault+0x225/0x6c0
[<0>] exc_page_fault+0x84/0x1b0
[<0>] asm_exc_page_fault+0x27/0x30

This requires a reboot to resolve; it is a deadlock.

Note however that the call to cifs_readpage_from_fscache does mark the
page clean, but does not free the folio lock. This happens in
__cifs_readpage_from_fscache on success. Releasing the lock at that
point however is not appropriate as cifs_readahead also calls
cifs_readpage_from_fscache and *does* unconditionally release the lock
after its return. This change therefore effectively makes
cifs_readpage_worker work like cifs_readahead.

Signed-off-by: Russell Harmon <russ@har.mn>
Acked-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-14 08:39:12 -05:00
Linus Torvalds
a785fd28d3 for-6.5-rc5-tag
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Merge tag 'for-6.5-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "More fixes, some of them going back to older releases and there are
  fixes for hangs in stress tests regarding space caching:

   - fixes and progress tracking for hangs in free space caching, found
     by test generic/475

   - writeback fixes, write pages in integrity mode and skip writing
     pages that have been written meanwhile

   - properly clear end of extent range after an error

   - relocation fixes:
      - fix race betwen qgroup tree creation and relocation
      - detect and report invalid reloc roots"

* tag 'for-6.5-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: set cache_block_group_error if we find an error
  btrfs: reject invalid reloc tree root keys with stack dump
  btrfs: exit gracefully if reloc roots don't match
  btrfs: avoid race between qgroup tree creation and relocation
  btrfs: properly clear end of the unreserved range in cow_file_range
  btrfs: don't wait for writeback on clean pages in extent_write_cache_pages
  btrfs: don't stop integrity writeback too early
  btrfs: wait for actual caching progress during allocation
2023-08-12 13:28:55 -07:00
Mateusz Guzik
c8afaa1b0f locking: remove spin_lock_prefetch
The only remaining consumer is new_inode, where it showed up in 2001 as
commit c37fa164f793 ("v2.4.9.9 -> v2.4.9.10") in a historical repo [1]
with a changelog which does not mention it.

Since then the line got only touched up to keep compiling.

While it may have been of benefit back in the day, it is guaranteed to
at best not get in the way in the multicore setting -- as the code
performs *a lot* of work between the prefetch and actual lock acquire,
any contention means the cacheline is already invalid by the time the
routine calls spin_lock().  It adds spurious traffic, for short.

On top of it prefetch is notoriously tricky to use for single-threaded
purposes, making it questionable from the get go.

As such, remove it.

I admit upfront I did not see value in benchmarking this change, but I
can do it if that is deemed appropriate.

Removal from new_inode and of the entire thing are in the same patch as
requested by Linus, so whatever weird looks can be directed at that guy.

Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/fs/inode.c?id=c37fa164f793735b32aa3f53154ff1a7659e6442 [1]
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-08-12 09:18:47 -07:00
Linus Torvalds
0725a70411 zonefs fixes for 6.5-rc6
- The switch to using iomap for executing direct synchronous write to
    sequential files using zone append BIO overlooked cases where the BIO
    built by iomap is too large and needs splitting, which is not allowed
    with zone append. Fix this by using regular write commands instead.
    The use of zone append commands will be reintroduces later with
    proper support from iomap.
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Merge tag 'zonefs-6.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs

Pull zonefs fix from Damien Le Moal:

 - The switch to using iomap for executing a direct synchronous write to
   sequential files using a zone append BIO overlooked cases where the
   BIO built by iomap is too large and needs splitting, which is not
   allowed with zone append.

   Fix this by using regular write commands instead. The use of zone
   append commands will be reintroduced later with proper support from
   iomap.

* tag 'zonefs-6.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
  zonefs: fix synchronous direct writes to sequential files
2023-08-11 18:35:56 -07:00
Linus Torvalds
190bf7b14b 14 hotfixes. 11 of these are cc:stable and the remainder address post-6.4
issues, or are not considered suitable for -stable backporting.
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Merge tag 'mm-hotfixes-stable-2023-08-11-13-44' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "14 hotfixes. 11 of these are cc:stable and the remainder address
  post-6.4 issues, or are not considered suitable for -stable
  backporting"

* tag 'mm-hotfixes-stable-2023-08-11-13-44' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm/damon/core: initialize damo_filter->list from damos_new_filter()
  nilfs2: fix use-after-free of nilfs_root in dirtying inodes via iput
  selftests: cgroup: fix test_kmem_basic false positives
  fs/proc/kcore: reinstate bounce buffer for KCORE_TEXT regions
  MAINTAINERS: add maple tree mailing list
  mm: compaction: fix endless looping over same migrate block
  selftests: mm: ksm: fix incorrect evaluation of parameter
  hugetlb: do not clear hugetlb dtor until allocating vmemmap
  mm: memory-failure: avoid false hwpoison page mapped error info
  mm: memory-failure: fix potential unexpected return value from unpoison_memory()
  mm/swapfile: fix wrong swap entry type for hwpoisoned swapcache page
  radix tree test suite: fix incorrect allocation size for pthreads
  crypto, cifs: fix error handling in extract_iter_to_sg()
  zsmalloc: fix races between modifications of fullness and isolated
2023-08-11 14:19:20 -07:00
Steve French
e8f5f849ff cifs: fix potential oops in cifs_oplock_break
With deferred close we can have closes that race with lease breaks,
and so with the current checks for whether to send the lease response,
oplock_response(), this can mean that an unmount (kill_sb) can occur
just before we were checking if the tcon->ses is valid.  See below:

[Fri Aug  4 04:12:50 2023] RIP: 0010:cifs_oplock_break+0x1f7/0x5b0 [cifs]
[Fri Aug  4 04:12:50 2023] Code: 7d a8 48 8b 7d c0 c0 e9 02 48 89 45 b8 41 89 cf e8 3e f5 ff ff 4c 89 f7 41 83 e7 01 e8 82 b3 03 f2 49 8b 45 50 48 85 c0 74 5e <48> 83 78 60 00 74 57 45 84 ff 75 52 48 8b 43 98 48 83 eb 68 48 39
[Fri Aug  4 04:12:50 2023] RSP: 0018:ffffb30607ddbdf8 EFLAGS: 00010206
[Fri Aug  4 04:12:50 2023] RAX: 632d223d32612022 RBX: ffff97136944b1e0 RCX: 0000000080100009
[Fri Aug  4 04:12:50 2023] RDX: 0000000000000001 RSI: 0000000080100009 RDI: ffff97136944b188
[Fri Aug  4 04:12:50 2023] RBP: ffffb30607ddbe58 R08: 0000000000000001 R09: ffffffffc08e0900
[Fri Aug  4 04:12:50 2023] R10: 0000000000000001 R11: 000000000000000f R12: ffff97136944b138
[Fri Aug  4 04:12:50 2023] R13: ffff97149147c000 R14: ffff97136944b188 R15: 0000000000000000
[Fri Aug  4 04:12:50 2023] FS:  0000000000000000(0000) GS:ffff9714f7c00000(0000) knlGS:0000000000000000
[Fri Aug  4 04:12:50 2023] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[Fri Aug  4 04:12:50 2023] CR2: 00007fd8de9c7590 CR3: 000000011228e000 CR4: 0000000000350ef0
[Fri Aug  4 04:12:50 2023] Call Trace:
[Fri Aug  4 04:12:50 2023]  <TASK>
[Fri Aug  4 04:12:50 2023]  process_one_work+0x225/0x3d0
[Fri Aug  4 04:12:50 2023]  worker_thread+0x4d/0x3e0
[Fri Aug  4 04:12:50 2023]  ? process_one_work+0x3d0/0x3d0
[Fri Aug  4 04:12:50 2023]  kthread+0x12a/0x150
[Fri Aug  4 04:12:50 2023]  ? set_kthread_struct+0x50/0x50
[Fri Aug  4 04:12:50 2023]  ret_from_fork+0x22/0x30
[Fri Aug  4 04:12:50 2023]  </TASK>

To fix this change the ordering of the checks before sending the oplock_response
to first check if the openFileList is empty.

Fixes: da787d5b74 ("SMB3: Do not send lease break acknowledgment if all file handles have been closed")
Suggested-by: Bharath SM <bharathsm@microsoft.com>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-10 21:05:45 -05:00
Josef Bacik
92fb94b69c btrfs: set cache_block_group_error if we find an error
We set cache_block_group_error if btrfs_cache_block_group() returns an
error, this is because we could end up not finding space to allocate and
mistakenly return -ENOSPC, and which could then abort the transaction
with the incorrect errno, and in the case of ENOSPC result in a
WARN_ON() that will trip up tests like generic/475.

However there's the case where multiple threads can be racing, one
thread gets the proper error, and the other thread doesn't actually call
btrfs_cache_block_group(), it instead sees ->cached ==
BTRFS_CACHE_ERROR.  Again the result is the same, we fail to allocate
our space and return -ENOSPC.  Instead we need to set
cache_block_group_error to -EIO in this case to make sure that if we do
not make our allocation we get the appropriate error returned back to
the caller.

CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 17:16:45 +02:00
Qu Wenruo
6ebcd021c9 btrfs: reject invalid reloc tree root keys with stack dump
[BUG]
Syzbot reported a crash that an ASSERT() got triggered inside
prepare_to_merge().

That ASSERT() makes sure the reloc tree is properly pointed back by its
subvolume tree.

[CAUSE]
After more debugging output, it turns out we had an invalid reloc tree:

  BTRFS error (device loop1): reloc tree mismatch, root 8 has no reloc root, expect reloc root key (-8, 132, 8) gen 17

Note the above root key is (TREE_RELOC_OBJECTID, ROOT_ITEM,
QUOTA_TREE_OBJECTID), meaning it's a reloc tree for quota tree.

But reloc trees can only exist for subvolumes, as for non-subvolume
trees, we just COW the involved tree block, no need to create a reloc
tree since those tree blocks won't be shared with other trees.

Only subvolumes tree can share tree blocks with other trees (thus they
have BTRFS_ROOT_SHAREABLE flag).

Thus this new debug output proves my previous assumption that corrupted
on-disk data can trigger that ASSERT().

[FIX]
Besides the dedicated fix and the graceful exit, also let tree-checker to
check such root keys, to make sure reloc trees can only exist for subvolumes.

CC: stable@vger.kernel.org # 5.15+
Reported-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 17:14:42 +02:00
Qu Wenruo
05d7ce5045 btrfs: exit gracefully if reloc roots don't match
[BUG]
Syzbot reported a crash that an ASSERT() got triggered inside
prepare_to_merge().

[CAUSE]
The root cause of the triggered ASSERT() is we can have a race between
quota tree creation and relocation.

This leads us to create a duplicated quota tree in the
btrfs_read_fs_root() path, and since it's treated as fs tree, it would
have ROOT_SHAREABLE flag, causing us to create a reloc tree for it.

The bug itself is fixed by a dedicated patch for it, but this already
taught us the ASSERT() is not something straightforward for
developers.

[ENHANCEMENT]
Instead of using an ASSERT(), let's handle it gracefully and output
extra info about the mismatch reloc roots to help debug.

Also with the above ASSERT() removed, we can trigger ASSERT(0)s inside
merge_reloc_roots() later.
Also replace those ASSERT(0)s with WARN_ON()s.

CC: stable@vger.kernel.org # 5.15+
Reported-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 17:13:13 +02:00
Qu Wenruo
773e722a98 btrfs: avoid race between qgroup tree creation and relocation
[BUG]
Syzbot reported a weird ASSERT() triggered inside prepare_to_merge().

  assertion failed: root->reloc_root == reloc_root, in fs/btrfs/relocation.c:1919
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/relocation.c:1919!
  invalid opcode: 0000 [#1] PREEMPT SMP KASAN
  CPU: 0 PID: 9904 Comm: syz-executor.3 Not tainted
  6.4.0-syzkaller-08881-g533925cb7604 #0
  Hardware name: Google Google Compute Engine/Google Compute Engine,
  BIOS Google 05/27/2023
  RIP: 0010:prepare_to_merge+0xbb2/0xc40 fs/btrfs/relocation.c:1919
  Code: fe e9 f5 (...)
  RSP: 0018:ffffc9000325f760 EFLAGS: 00010246
  RAX: 000000000000004f RBX: ffff888075644030 RCX: 1481ccc522da5800
  RDX: ffffc90005c09000 RSI: 00000000000364ca RDI: 00000000000364cb
  RBP: ffffc9000325f870 R08: ffffffff816f33ac R09: 1ffff9200064bea0
  R10: dffffc0000000000 R11: fffff5200064bea1 R12: ffff888075644000
  R13: ffff88803b166000 R14: ffff88803b166560 R15: ffff88803b166558
  FS:  00007f4e305fd700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000056080679c000 CR3: 00000000193ad000 CR4: 00000000003506f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   relocate_block_group+0xa5d/0xcd0 fs/btrfs/relocation.c:3749
   btrfs_relocate_block_group+0x7ab/0xd70 fs/btrfs/relocation.c:4087
   btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3283
   __btrfs_balance+0x1b06/0x2690 fs/btrfs/volumes.c:4018
   btrfs_balance+0xbdb/0x1120 fs/btrfs/volumes.c:4402
   btrfs_ioctl_balance+0x496/0x7c0 fs/btrfs/ioctl.c:3604
   vfs_ioctl fs/ioctl.c:51 [inline]
   __do_sys_ioctl fs/ioctl.c:870 [inline]
   __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:856
   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
   do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
  RIP: 0033:0x7f4e2f88c389

[CAUSE]
With extra debugging, the offending reloc_root is for quota tree (rootid 8).

Normally we should not use the reloc tree for quota root at all, as reloc
trees are only for subvolume trees.

But there is a race between quota enabling and relocation, this happens
after commit 85724171b3 ("btrfs: fix the btrfs_get_global_root return value").

Before that commit, for quota and free space tree, we exit immediately
if we cannot grab it from fs_info.

But now we would try to read it from disk, just as if they are fs trees,
this sets ROOT_SHAREABLE flags in such race:

             Thread A             |           Thread B
 ---------------------------------+------------------------------
 btrfs_quota_enable()             |
 |                                | btrfs_get_root_ref()
 |                                | |- btrfs_get_global_root()
 |                                | |  Returned NULL
 |                                | |- btrfs_lookup_fs_root()
 |                                | |  Returned NULL
 |- btrfs_create_tree()           | |
 |  Now quota root item is        | |
 |  inserted                      | |- btrfs_read_tree_root()
 |                                | |  Got the newly inserted quota root
 |                                | |- btrfs_init_fs_root()
 |                                | |  Set ROOT_SHAREABLE flag

[FIX]
Get back to the old behavior by returning PTR_ERR(-ENOENT) if the target
objectid is not a subvolume tree or data reloc tree.

Reported-and-tested-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com
Fixes: 85724171b3 ("btrfs: fix the btrfs_get_global_root return value")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 17:10:10 +02:00
Christoph Hellwig
12b2d64e59 btrfs: properly clear end of the unreserved range in cow_file_range
When the call to btrfs_reloc_clone_csums in cow_file_range returns an
error, we jump to the out_unlock label with the extent_reserved variable
set to false.   The cleanup at the label will then call
extent_clear_unlock_delalloc on the range from start to end.  But we've
already added cur_alloc_size to start before the jump, so there might no
range be left from the newly incremented start to end.  Move the check for
'start < end' so that it is reached by also for the !extent_reserved case.

CC: stable@vger.kernel.org # 6.1+
Fixes: a315e68f6e ("Btrfs: fix invalid attempt to free reserved space on failure to cow range")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 17:07:10 +02:00
Christoph Hellwig
5c25699871 btrfs: don't wait for writeback on clean pages in extent_write_cache_pages
__extent_writepage could have started on more pages than the one it was
called for.  This happens regularly for zoned file systems, and in theory
could happen for compressed I/O if the worker thread was executed very
quickly. For such pages extent_write_cache_pages waits for writeback
to complete before moving on to the next page, which is highly inefficient
as it blocks the flusher thread.

Port over the PageDirty check that was added to write_cache_pages in
commit 515f4a037f ("mm: write_cache_pages optimise page cleaning") to
fix this.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 17:04:09 +02:00
Christoph Hellwig
effa24f689 btrfs: don't stop integrity writeback too early
extent_write_cache_pages stops writing pages as soon as nr_to_write hits
zero.  That is the right thing for opportunistic writeback, but incorrect
for data integrity writeback, which needs to ensure that no dirty pages
are left in the range.  Thus only stop the writeback for WB_SYNC_NONE
if nr_to_write hits 0.

This is a port of write_cache_pages changes in commit 05fe478dd0
("mm: write_cache_pages integrity fix").

Note that I've only trigger the problem with other changes to the btrfs
writeback code, but this condition seems worthwhile fixing anyway.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ updated comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 16:59:34 +02:00
Josef Bacik
fc1f91b923 btrfs: wait for actual caching progress during allocation
Recently we've been having mysterious hangs while running generic/475 on
the CI system.  This turned out to be something like this:

  Task 1
  dmsetup suspend --nolockfs
  -> __dm_suspend
   -> dm_wait_for_completion
    -> dm_wait_for_bios_completion
     -> Unable to complete because of IO's on a plug in Task 2

  Task 2
  wb_workfn
  -> wb_writeback
   -> blk_start_plug
    -> writeback_sb_inodes
     -> Infinite loop unable to make an allocation

  Task 3
  cache_block_group
  ->read_extent_buffer_pages
   ->Waiting for IO to complete that can't be submitted because Task 1
     suspended the DM device

The problem here is that we need Task 2 to be scheduled completely for
the blk plug to flush.  Normally this would happen, we normally wait for
the block group caching to finish (Task 3), and this schedule would
result in the block plug flushing.

However if there's enough free space available from the current caching
to satisfy the allocation we won't actually wait for the caching to
complete.  This check however just checks that we have enough space, not
that we can make the allocation.  In this particular case we were trying
to allocate 9MiB, and we had 10MiB of free space, but we didn't have
9MiB of contiguous space to allocate, and thus the allocation failed and
we looped.

We specifically don't cycle through the FFE loop until we stop finding
cached block groups because we don't want to allocate new block groups
just because we're caching, so we short circuit the normal loop once we
hit LOOP_CACHING_WAIT and we found a caching block group.

This is normally fine, except in this particular case where the caching
thread can't make progress because the DM device has been suspended.

Fix this by not only waiting for free space to >= the amount of space we
want to allocate, but also that we make some progress in caching from
the time we start waiting.  This will keep us from busy looping when the
caching is taking a while but still theoretically has enough space for
us to allocate from, and fixes this particular case by forcing us to
actually sleep and wait for forward progress, which will flush the plug.

With this fix we're no longer hanging with generic/475.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 16:44:14 +02:00
Linus Torvalds
374a7f47bf two ksmbd server fixes
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Merge tag '6.5-rc5-ksmbd-server' of git://git.samba.org/ksmbd

Pull smb server fixes from Steve French:
 "Two ksmbd server fixes, both also for stable:

   - improve buffer validation when multiple EAs returned

   - missing check for command payload size"

* tag '6.5-rc5-ksmbd-server' of git://git.samba.org/ksmbd:
  ksmbd: fix wrong next length validation of ea buffer in smb2_set_ea()
  ksmbd: validate command request size
2023-08-09 21:12:56 -07:00