13193 Commits

Author SHA1 Message Date
Josef Bacik
7fcee18da4 btrfs: push lookup_info into struct walk_control
Instead of using a flag we're passing around everywhere, add a field to
walk_control that we're already passing around everywhere and use that
instead.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:24 +02:00
Josef Bacik
3fdf5798fa btrfs: use btrfs_read_extent_buffer() in do_walk_down()
Currently if our extent buffer isn't uptodate we will drop the lock,
free it, and then call read_tree_block() for the bytenr.  This is
inefficient, we already have the extent buffer, we can simply call
btrfs_read_extent_buffer().

Merge these two cases down into one if statement, if we are not uptodate
we can drop the lock, trigger readahead, and do the read using
btrfs_read_extent_buffer(), and carry on.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:24 +02:00
Josef Bacik
133b3da835 btrfs: remove all extra btrfs_check_eb_owner() calls
Currently we have a handful of btrfs_check_eb_owner() calls in various
places and helpers that read extent buffers.  However we call this in
the endio handler for every metadata block, so these extra checks are
unnecessary, simply remove them from everywhere except the endio
handler.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:24 +02:00
Josef Bacik
58147d5a70 btrfs: don't do extra find_extent_buffer() in do_walk_down()
We do find_extent_buffer(), and then if we don't find the eb in cache we
call btrfs_find_create_tree_block(), which calls find_extent_buffer()
first and then allocates the extent buffer.

The reason we're doing this is because if we don't find the extent
buffer in cache we set reada = 1.  However this doesn't matter, because
lower down we only trigger reada if !btrfs_buffer_uptodate(eb), which is
what the case would be if we didn't find the extent buffer in cache and
had to allocate it.

Clean this up to simply call btrfs_find_create_tree_block(), and then
use the fact that we're having to read the extent buffer off of disk to
go ahead and kick off readahead.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:24 +02:00
Filipe Manana
45c4102f0d btrfs: avoid transaction commit on any fsync after subvolume creation
As of commit 1b53e51a4a8f ("btrfs: don't commit transaction for every
subvol create") we started to make any fsync after creating a subvolume
to fallback to a transaction commit if the fsync is performed in the
same transaction that was used to create the subvolume. This happens
with the following at ioctl.c:create_subvol():

  $ cat fs/btrfs/ioctl.c
  (...)
      /* Tree log can't currently deal with an inode which is a new root. */
      btrfs_set_log_full_commit(trans);
  (...)

Note that the comment is misleading as the problem is not that fsync can
not deal with the root inode of a new root, but that we can not log any
inode that belongs to a root that was not yet persisted because that would
make log replay fail since the root doesn't exist at log replay time.

The above simply makes any fsync fallback to a full transaction commit if
it happens in the same transaction used to create the subvolume - even if
it's an inode that belongs to any other subvolume. This is a brute force
solution and it doesn't necessarily improve performance for every workload
out there - it just moves a full transaction commit from one place, the
subvolume creation, to another - an fsync for any inode.

Just improve on this by making the fallback to a transaction commit only
for an fsync against an inode of the new subvolume, or for the directory
that contains the dentry that points to the new subvolume (in case anyone
attempts to fsync the directory in the same transaction).

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:24 +02:00
Filipe Manana
ebc7c7678e btrfs: remove pointless code when creating and deleting a subvolume
When creating and deleting a subvolume, after starting a transaction we
are explicitly calling btrfs_record_root_in_trans() for the root which we
passed to btrfs_start_transaction(). This is pointless because at
transaction.c:start_transaction() we end up doing that call, regardless
of whether we actually start a new transaction or join an existing one,
and if we were not it would mean the root item of that root would not
be updated in the root tree when committing the transaction, leading to
problems easy to spot with fstests for example.

Remove these redundant calls. They were introduced with commit
74e97958121a ("btrfs: qgroup: fix qgroup prealloc rsv leak in subvolume
operations").

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:24 +02:00
Johannes Thumshirn
6d81df75af btrfs: pass reloc_control to setup_relocation_extent_mapping()
All parameters passed into setup_relocation_extent_mapping() can be
derived from 'struct reloc_control', so only pass in a 'struct
reloc_control'.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Johannes Thumshirn
60f3dabdbc btrfs: pass a struct reloc_control to prealloc_file_extent_cluster()
Pass a 'struct reloc_control' to prealloc_file_extent_cluster()
instead of passing its members 'data_inode' and 'cluster' on their own.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Johannes Thumshirn
17a21d7914 btrfs: don't pass fs_info to describe_relocation()
In describe_relocation() the fs_info is only needed for printing
information via btrfs_info() and can easily be accessed via the passed
in 'struct btrfs_block_group'.

So we can safely remove the fs_info parameter.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Johannes Thumshirn
912eea7e24 btrfs: pass a reloc_control to relocate_one_folio()
Pass a struct reloc_control to relocate_one_folio, instead of passing
it's members data_inode and cluster as separate arguments to the function.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Johannes Thumshirn
2e9e8dcdd5 btrfs: pass a reloc_control to relocate_file_extent_cluster()
Instead of passing in a reloc_control's data_inode and
file_extent_cluster members, pass in the whole reloc_control structure.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Johannes Thumshirn
fa4adfc786 btrfs: pass reloc_control to relocate_data_extent()
Pass a 'struct reloc_control' to relocate_data_extent() instead of
it's data_inode and file_extent_cluster separately.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Filipe Manana
8b62f14d99 btrfs: update panic message when splitting ordered extent
During ordered extent splitting if we find a duplicated ordered extent
when attempting to insert the new ordered extent we panic but with a
message that has the "zoned:" prefix. This is because the splitting used
to be exclusive for zoned filesystems, but as of commit b73a6fd1b1ef
("btrfs: split partial dio bios before submit") it can also be done for
non zoned filesystems during direct IO writes. So remove the "zoned:"
prefix from the message and mention the split to make it more specific
and different from the panic message at insert_ordered_extent().

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Filipe Manana
b7ac1acbdd btrfs: mark ordered extent insertion failure checks as unlikely
We never expect an ordered extent insertion to fail due to already having
another ordered extent in the tree for the same file offset, since we
always wait for existing ordered extents in a range to complete before
writing into the range again. So mark the failure checks for the results
of tree_insert() as unlikely, to make it clear it's never expected (save
exceptional causes like bugs or memory corruptions) and to serve as a hint
for the compiler to possibly generate better code.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Filipe Manana
cb3cd62454 btrfs: avoid removal and re-insertion of split ordered extent
At btrfs_split_ordered_extent(), we are removing and re-inserting the
ordered extent that we are trimming, but we don't need to since the
trimming doesn't change its position in the red black tree because we
don't have overlapping ordered extents (that would imply double allocation
of extents) and we know the split length is smaller than the ordered
extent's num_bytes field (we checked that early in the function).

So drop the remove and re-insert code for the slit ordered extent.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Filipe Manana
c18ca3c960 btrfs: add comment about locking to btrfs_split_ordered_extent()
There are subtle details about why the root's ordered_extent_lock is held,
so add a comment mentioning them.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Filipe Manana
ac1f580c10 btrfs: reduce critical section at btrfs_wait_ordered_extents()
At btrfs_wait_ordered_extents(), there's no point in updating the counters
after locking the root's ordered extent lock, as the counters are local.
So change this to update the counters before taking the lock.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:23 +02:00
Filipe Manana
03103ecf5e btrfs: reduce critical section at btrfs_wait_ordered_roots()
At btrfs_wait_ordered_roots(), there's no point in decrementing the
counter after locking fs_info->ordered_root_lock as the counter is local.
So change this to decrement the counter before taking the lock.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
David Sterba
2917f74102 btrfs: constify pointer parameters where applicable
We can add const to many parameters, this is for clarity and minor
addition to safety. There are some minor effects, in the assembly
code and .ko measured on release config. This patch does not cover all
possible conversions.

Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Qu Wenruo
c27b1dbb71 btrfs: do not directly include rwlock_types.h
There is already an error inside that header:

 #if !defined(__LINUX_SPINLOCK_TYPES_H)
 # error "Do not include directly, include spinlock_types.h"
 #endif

Thankfully it never get triggered as some other headers have already
included spinlock_types.h.

However clangd would still do a proper warning on that if only
extent_map.h is opened.
Fix it by using spinlock_types.h instead.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Qu Wenruo
3b8dbf3425 btrfs: cleanup recursive include of the same header
We have several headers that are including themselves, triggering clangd
warnings.
Such includes are caused by commit 602035d7fecf ("btrfs: add forward
declarations and headers, part 2").

Just remove such unnecessary include.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Junchao Sun
a56b795234 btrfs: qgroup: delete a TODO about using kmem cache to allocate structures
Generic slab works fine allocating btrfs_qgroup_extent_record
structures. It's not necessary to create a dedicated kmem cache that
would be created but unused if quotas were not enabled. Let's delete the
TODO line.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Junchao Sun <sunjunchao2870@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Qu Wenruo
a185373e53 btrfs: make extent_write_locked_range() handle subpage writeback correctly
When extent_write_locked_range() generated an inline extent, it would
set and finish the writeback for the whole page.

Although currently it's safe since subpage disables inline creation,
for the sake of consistency, let it go with subpage helpers to set and
clear the writeback flags.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Qu Wenruo
97713b1a2c btrfs: do not clear page dirty inside extent_write_locked_range()
[BUG]
For subpage + zoned case, the following workload can lead to rsv data
leak at unmount time:

  # mkfs.btrfs -f -s 4k $dev
  # mount $dev $mnt
  # fsstress -w -n 8 -d $mnt -s 1709539240
  0/0: fiemap - no filename
  0/1: copyrange read - no filename
  0/2: write - no filename
  0/3: rename - no source filename
  0/4: creat f0 x:0 0 0
  0/4: creat add id=0,parent=-1
  0/5: writev f0[259 1 0 0 0 0] [778052,113,965] 0
  0/6: ioctl(FIEMAP) f0[259 1 0 0 224 887097] [1294220,2291618343991484791,0x10000] -1
  0/7: dwrite - xfsctl(XFS_IOC_DIOINFO) f0[259 1 0 0 224 887097] return 25, fallback to stat()
  0/7: dwrite f0[259 1 0 0 224 887097] [696320,102400] 0
  # umount $mnt

The dmesg includes the following rsv leak detection warning (all call
trace skipped):

  ------------[ cut here ]------------
  WARNING: CPU: 2 PID: 4528 at fs/btrfs/inode.c:8653 btrfs_destroy_inode+0x1e0/0x200 [btrfs]
  ---[ end trace 0000000000000000 ]---
  ------------[ cut here ]------------
  WARNING: CPU: 2 PID: 4528 at fs/btrfs/inode.c:8654 btrfs_destroy_inode+0x1a8/0x200 [btrfs]
  ---[ end trace 0000000000000000 ]---
  ------------[ cut here ]------------
  WARNING: CPU: 2 PID: 4528 at fs/btrfs/inode.c:8660 btrfs_destroy_inode+0x1a0/0x200 [btrfs]
  ---[ end trace 0000000000000000 ]---
  BTRFS info (device sda): last unmount of filesystem 1b4abba9-de34-4f07-9e7f-157cf12a18d6
  ------------[ cut here ]------------
  WARNING: CPU: 3 PID: 4528 at fs/btrfs/block-group.c:4434 btrfs_free_block_groups+0x338/0x500 [btrfs]
  ---[ end trace 0000000000000000 ]---
  BTRFS info (device sda): space_info DATA has 268218368 free, is not full
  BTRFS info (device sda): space_info total=268435456, used=204800, pinned=0, reserved=0, may_use=12288, readonly=0 zone_unusable=0
  BTRFS info (device sda): global_block_rsv: size 0 reserved 0
  BTRFS info (device sda): trans_block_rsv: size 0 reserved 0
  BTRFS info (device sda): chunk_block_rsv: size 0 reserved 0
  BTRFS info (device sda): delayed_block_rsv: size 0 reserved 0
  BTRFS info (device sda): delayed_refs_rsv: size 0 reserved 0
  ------------[ cut here ]------------
  WARNING: CPU: 3 PID: 4528 at fs/btrfs/block-group.c:4434 btrfs_free_block_groups+0x338/0x500 [btrfs]
  ---[ end trace 0000000000000000 ]---
  BTRFS info (device sda): space_info METADATA has 267796480 free, is not full
  BTRFS info (device sda): space_info total=268435456, used=131072, pinned=0, reserved=0, may_use=262144, readonly=0 zone_unusable=245760
  BTRFS info (device sda): global_block_rsv: size 0 reserved 0
  BTRFS info (device sda): trans_block_rsv: size 0 reserved 0
  BTRFS info (device sda): chunk_block_rsv: size 0 reserved 0
  BTRFS info (device sda): delayed_block_rsv: size 0 reserved 0
  BTRFS info (device sda): delayed_refs_rsv: size 0 reserved 0

Above $dev is a tcmu-runner emulated zoned HDD, which has a max zone
append size of 64K, and the system has 64K page size.

[CAUSE]
I have added several trace_printk() to show the events (header skipped):

  > btrfs_dirty_pages: r/i=5/259 dirty start=774144 len=114688
  > btrfs_dirty_pages: r/i=5/259 dirty part of page=720896 off_in_page=53248 len_in_page=12288
  > btrfs_dirty_pages: r/i=5/259 dirty part of page=786432 off_in_page=0 len_in_page=65536
  > btrfs_dirty_pages: r/i=5/259 dirty part of page=851968 off_in_page=0 len_in_page=36864

The above lines show our buffered write has dirtied 3 pages of inode
259 of root 5:

  704K             768K              832K              896K
  I           |////I/////////////////I///////////|     I
              756K                               868K

  |///| is the dirtied range using subpage bitmaps. and 'I' is the page
  boundary.

  Meanwhile all three pages (704K, 768K, 832K) have their PageDirty
  flag set.

  > btrfs_direct_write: r/i=5/259 start dio filepos=696320 len=102400

Then direct IO write starts, since the range [680K, 780K) covers the
beginning part of the above dirty range, we need to writeback the
two pages at 704K and 768K.

  > cow_file_range: r/i=5/259 add ordered extent filepos=774144 len=65536
  > extent_write_locked_range: r/i=5/259 locked page=720896 start=774144 len=65536

Now the above 2 lines show that we're writing back for dirty range
[756K, 756K + 64K).
We only writeback 64K because the zoned device has max zone append size
as 64K.

  > extent_write_locked_range: r/i=5/259 clear dirty for page=786432

!!! The above line shows the root cause. !!!

We're calling clear_page_dirty_for_io() inside extent_write_locked_range(),
for the page 768K.
This is because extent_write_locked_range() can go beyond the current
locked page, here we hit the page at 768K and clear its page dirt.

In fact this would lead to the desync between subpage dirty and page
dirty flags.  We have the page dirty flag cleared, but the subpage range
[820K, 832K) is still dirty.

After the writeback of range [756K, 820K), the dirty flags look like
this, as page 768K no longer has dirty flag set.

  704K             768K              832K              896K
  I                I      |          I/////////////|   I
                          820K                     868K

This means we will no longer writeback range [820K, 832K), thus the
reserved data/metadata space would never be properly released.

  > extent_write_cache_pages: r/i=5/259 skip non-dirty folio=786432

Now even though we try to start writeback for page 768K, since the
page is not dirty, we completely skip it at extent_write_cache_pages()
time.

  > btrfs_direct_write: r/i=5/259 dio done filepos=696320 len=0

Now the direct IO finished.

  > cow_file_range: r/i=5/259 add ordered extent filepos=851968 len=36864
  > extent_write_locked_range: r/i=5/259 locked page=851968 start=851968 len=36864

Now we writeback the remaining dirty range, which is [832K, 868K).
Causing the range [820K, 832K) never to be submitted, thus leaking the
reserved space.

This bug only affects subpage and zoned case.  For non-subpage and zoned
case, we have exactly one sector for each page, thus no such partial dirty
cases.

For subpage and non-zoned case, we never go into run_delalloc_cow(), and
normally all the dirty subpage ranges would be properly submitted inside
__extent_writepage_io().

[FIX]
Just do not clear the page dirty at all inside extent_write_locked_range().
As __extent_writepage_io() would do a more accurate, subpage compatible
clear for page and subpage dirty flags anyway.

Now the correct trace would look like this:

  > btrfs_dirty_pages: r/i=5/259 dirty start=774144 len=114688
  > btrfs_dirty_pages: r/i=5/259 dirty part of page=720896 off_in_page=53248 len_in_page=12288
  > btrfs_dirty_pages: r/i=5/259 dirty part of page=786432 off_in_page=0 len_in_page=65536
  > btrfs_dirty_pages: r/i=5/259 dirty part of page=851968 off_in_page=0 len_in_page=36864

The page dirty part is still the same 3 pages.

  > btrfs_direct_write: r/i=5/259 start dio filepos=696320 len=102400
  > cow_file_range: r/i=5/259 add ordered extent filepos=774144 len=65536
  > extent_write_locked_range: r/i=5/259 locked page=720896 start=774144 len=65536

And the writeback for the first 64K is still correct.

  > cow_file_range: r/i=5/259 add ordered extent filepos=839680 len=49152
  > extent_write_locked_range: r/i=5/259 locked page=786432 start=839680 len=49152

Now with the fix, we can properly writeback the range [820K, 832K), and
properly release the reserved data/metadata space.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Qu Wenruo
d034cdb4cc btrfs: lock subpage ranges in one go for writepage_delalloc()
If we have a subpage range like this for a 16K page with 4K sectorsize:

    0     4K     8K     12K     16K
    |/////|      |//////|       |

    |/////| = dirty range

Currently writepage_delalloc() would go through the following steps:

- lock range [0, 4K)
- run delalloc range for [0, 4K)
- lock range [8K, 12K)
- run delalloc range for [8K 12K)

So far it's fine for regular subpage writeback, as
btrfs_run_delalloc_range() can only go into one of run_delalloc_nocow(),
cow_file_range() and run_delalloc_compressed().

But there is a special case for zoned subpage, where we will go
through run_delalloc_cow(), which would create the ordered extent for the
range and immediately submit the range.
This would unlock the whole page range, causing all kinds of different
ASSERT()s related to locked page.

Address the page unlocking problem of run_delalloc_cow(), by changing
the workflow to the following one:

- lock range [0, 4K)
- lock range [8K, 12K)
- run delalloc range for [0, 4K)
- run delalloc range for [8K, 12K)

So that run_delalloc_cow() can only unlock the full page until the
last lock user released.

To do that:

- Utilize subpage locked bitmap
  So for every delalloc range we found, call
  btrfs_folio_set_writer_lock() to populate the subpage locked bitmap,
  and later btrfs_folio_end_all_writers() if the page is fully unlocked.

  So we know there is a delalloc range that needs to be run later.

- Save the @delalloc_end as @last_delalloc_end inside writepage_delalloc()
  Since subpage locked bitmap is only for ranges inside the page,
  meanwhile we can have delalloc range ends beyond our page boundary,
  we have to save the @last_delalloc_end just in case it's beyond our
  page boundary.

Although there is one extra point to notice:

- We need to handle errors in previous iteration
  Since we can have multiple locked delalloc ranges we have to call
  run_delalloc_ranges() multiple times.
  If we hit an error half way, we still need to unlock the remaining
  ranges.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Qu Wenruo
bca707e542 btrfs: subpage: introduce helpers to handle subpage delalloc locking
Three new helpers are introduced for the incoming subpage delalloc locking
change.

- btrfs_folio_set_writer_lock()
  This is to mark specified range with subpage specific writer lock.
  After calling this, the subpage range can be proper unlocked by
  btrfs_folio_end_writer_lock()

- btrfs_subpage_find_writer_locked()
  This is to find the writer locked subpage range in a page.
  With the help of btrfs_folio_set_writer_lock(), it can allow us to
  record and find previously locked subpage range without extra memory
  allocation.

- btrfs_folio_end_all_writers()
  This is for the locked_page of __extent_writepage(), as there may be
  multiple subpage delalloc ranges locked.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Qu Wenruo
21b5bef20e btrfs: make __extent_writepage_io() to write specified range only
Function __extent_writepage_io() is designed to find all dirty ranges of
a page, and add the dirty ranges to the bio_ctrl for submission.
It requires all the dirtied ranges to be covered by an ordered extent.

It gets called in two locations, but one call site is not subpage aware:

- __extent_writepage()
  It gets called when writepage_delalloc() returned 0, which means
  writepage_delalloc() has handled delalloc for all subpage sectors
  inside the page.

  So this call site is OK.

- extent_write_locked_range()
  This call site is utilized by zoned support, and in this case, we may
  only run delalloc range for a subset of the page, like this: (64K page
  size)

  0     16K     32K     48K     64K
  |/////|       |///////|       |

  In the above case, if extent_write_locked_range() is only triggered for
  range [0, 16K), __extent_writepage_io() would still try to submit
  the dirty range of [32K, 48K), then it would not find any ordered
  extent for it and triggers various ASSERT()s.

Fix this problem by:

- Introducing @start and @len parameters to specify the range

  For the first call site, we just pass the whole page, and the behavior
  is not touched, since run_delalloc_range() for the page should have
  created all ordered extents for the page.

  For the second call site, we avoid touching anything beyond the
  range, thus avoiding the dirty range which is not yet covered by any
  delalloc range.

- Making btrfs_folio_assert_not_dirty() subpage aware
  The only caller is inside __extent_writepage_io(), and since that
  caller now accepts a subpage range, we should also check the subpage
  range other than the whole page.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:22 +02:00
Jeff Johnson
95359f6322 btrfs: add MODULE_DESCRIPTION()
Fix the 'make W=1' warning:
WARNING: modpost: missing MODULE_DESCRIPTION() in fs/btrfs/btrfs.o

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Anand Jain
ca8ba2ccdc btrfs: rename err to ret in btrfs_drop_snapshot()
Drop the variable 'err', reuse the variable 'ret' by reinitializing it to
zero where necessary.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Anand Jain
ced1b1bd21 btrfs: rename err to ret in btrfs_recover_relocation()
Fix coding style: rename the return variable to 'ret' in the function
btrfs_recover_relocation instead of 'err'.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Anand Jain
bd0d9a619a btrfs: rename ret to ret2 in btrfs_recover_relocation()
A preparatory patch to rename 'err' to 'ret', but ret is already used as an
intermediary return value, so first rename 'ret' to 'ret2'.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Anand Jain
ba69f42af2 btrfs: rename ret to err in btrfs_recover_relocation()
In the function btrfs_recover_relocation(), currently the variable 'err'
carries the return value and 'ret' holds the intermediary return value.
However, in some lines, we don't need this two-step approach; we can
directly use 'err'. So, optimize them, which requires reinitializing 'err'
to zero at two locations.

This is a preparatory patch to fix the code style by renaming 'err'
to 'ret'.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Anand Jain
53d6c0da0a btrfs: rename err to ret in btrfs_cleanup_fs_roots()
Since err represents the function return value, rename it as ret,
and rename the original ret, which serves as a helper return value,
to found. Also, optimize the code to continue call btrfs_put_root()
for the rest of the root if even after btrfs_orphan_cleanup() returns
error.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Qu Wenruo
04ef7631bf btrfs: cleanup duplicated parameters related to btrfs_create_dio_extent()
The following 3 parameters can be cleaned up using btrfs_file_extent
structure:

- len
  btrfs_file_extent::num_bytes

- orig_block_len
  btrfs_file_extent::disk_num_bytes

- ram_bytes
  btrfs_file_extent::ram_bytes

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Qu Wenruo
9fec848b3a btrfs: cleanup duplicated parameters related to create_io_em()
Most parameters of create_io_em() can be replaced by the members with
the same name inside btrfs_file_extent.

Do a direct parameters cleanup here.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Qu Wenruo
e9ea31fb5c btrfs: cleanup duplicated parameters related to btrfs_alloc_ordered_extent
All parameters after @filepos of btrfs_alloc_ordered_extent() can be
replaced with btrfs_file_extent structure.

This patch does the cleanup, meanwhile some points to note:

- Move btrfs_file_extent structure to ordered-data.h
  The structure is needed by both btrfs_alloc_ordered_extent() and
  can_nocow_extent(), but since btrfs_inode.h includes
  ordered-data.h, so we need to move the structure to ordered-data.h.

- Move the special handling of NOCOW/PREALLOC into
  btrfs_alloc_ordered_extent()
  This is to allow btrfs_split_ordered_extent() to properly split them
  for DIO.
  For now just move the handling into btrfs_alloc_ordered_extent() to
  simplify the callers.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Qu Wenruo
cdc627e65c btrfs: cleanup duplicated parameters related to can_nocow_file_extent_args
The following functions and structures can be simplified using the
btrfs_file_extent structure:

- can_nocow_extent()
  No need to return ram_bytes/orig_block_len through the parameter list,
  the @file_extent parameter contains all the needed info.

- can_nocow_file_extent_args
  The following members are no longer needed:

  * disk_bytenr
    This one is confusing as it's not really the
    btrfs_file_extent_item::disk_bytenr, but where the IO would be,
    thus it's file_extent::disk_bytenr + file_extent::offset now.

  * num_bytes
    Now file_extent::num_bytes.

  * extent_offset
    Now file_extent::offset.

  * disk_num_bytes
    Now file_extent::disk_num_bytes.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Qu Wenruo
c77a8c6100 btrfs: remove extent_map::block_start member
The member extent_map::block_start can be calculated from
extent_map::disk_bytenr + extent_map::offset for regular extents.
And otherwise just extent_map::disk_bytenr.

And this is already validated by the validate_extent_map().  Now we can
remove the member.

However there is a special case in btrfs_create_dio_extent() where we
for NOCOW/PREALLOC ordered extents cannot directly use the resulting
btrfs_file_extent, as btrfs_split_ordered_extent() cannot handle them
yet.

So for that call site, we pass file_extent->disk_bytenr +
file_extent->num_bytes as disk_bytenr for the ordered extent, and 0 for
offset.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:21 +02:00
Qu Wenruo
e28b851ed9 btrfs: remove extent_map::block_len member
The extent_map::block_len is either extent_map::len (non-compressed
extent) or extent_map::disk_num_bytes (compressed extent).

Since we already have sanity checks to do the cross-checks between the
new and old members, we can drop the old extent_map::block_len now.

For most call sites, they can manually select extent_map::len or
extent_map::disk_num_bytes, since most if not all of them have checked
if the extent is compressed.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Qu Wenruo
4aa7b5d178 btrfs: remove extent_map::orig_start member
Since we have extent_map::offset, the old extent_map::orig_start is just
extent_map::start - extent_map::offset for non-hole/inline extents.

And since the new extent_map::offset is already verified by
validate_extent_map() while the old orig_start is not, let's just remove
the old member from all call sites.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Qu Wenruo
3f255ece2f btrfs: introduce extra sanity checks for extent maps
Since extent_map structure has the all the needed members to represent a
file extent directly, we can apply all the file extent sanity checks to
an extent map.

The new sanity checks will cross check both the old members
(block_start/block_len/orig_start) and the new members
(disk_bytenr/disk_num_bytes/offset).

There is a special case for offset/orig_start/start cross check, we only
do such sanity check for compressed extent, as only compressed
read/encoded write really utilize orig_start.
This can be proved by the cleanup patch of orig_start.

The checks happens at the following times:

- add_extent_mapping()
  This is for newly added extent map

- replace_extent_mapping()
  This is for btrfs_drop_extent_map_range() and split_extent_map()

- try_merge_map()

For a lot of call sites we have to properly populate all the members to
pass the sanity check, meanwhile the following code needs extra
modification:

- setup_file_extents() from inode-tests
  The file extents layout of setup_file_extents() is already too invalid
  that tree-checker would reject most of them in real world.

  However there is just a special unaligned regular extent which has
  mismatched disk_num_bytes (4096) and ram_bytes (4096 - 1).
  So instead of dropping the whole test case, here we just unify
  disk_num_bytes and ram_bytes to 4096 - 1.

- test_case_7() from extent-map-tests
  An extent is inserted with 16K length, but on-disk extent size is
  only 4K.
  This means it must be a compressed extent, so set the compressed flag
  for it.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Qu Wenruo
3d2ac99224 btrfs: introduce new members for extent_map
Introduce two new members for extent_map:

- disk_bytenr
- offset

Both are matching the members with the same name inside
btrfs_file_extent_items.

For now this patch only touches those members when:

- Reading btrfs_file_extent_items from disk
- Inserting new holes
- Merging two extent maps
  With the new disk_bytenr and disk_num_bytes, doing merging would be a
  little more complex, as we have 3 different cases:

  * Both extent maps are referring to the same data extents
    |<----- data extent A ----->|
       |<- em 1 ->|<- em 2 ->|

  * Both extent maps are referring to different data extents
    |<-- data extent A -->|<-- data extent B -->|
               |<- em 1 ->|<- em 2 ->|

  * One of the extent maps is referring to a merged and larger data
    extent that covers both extent maps

    This is not really valid case other than some selftests.
    So this test case would be removed.

  A new helper merge_ondisk_extents() is introduced to handle the above
  valid cases.

To properly assign values for those new members, a new btrfs_file_extent
parameter is introduced to all the involved call sites.

- For NOCOW writes the btrfs_file_extent would be exposed from
  can_nocow_file_extent().

- For other writes, the members can be easily calculated
  As most of them have 0 offset and utilizing the whole on-disk data
  extent.
  The exception is encoded write, but thankfully that interface provided
  offset directly and all other needed info.

For now, both the old members (block_start/block_len/orig_start) are
co-existing with the new members (disk_bytenr/offset), meanwhile all the
critical code is still using the old members only.

The cleanup will happen later after all the old and new members are
properly validated.

There would be some re-ordering for the assignment of the extent_map
members, now we follow the new ordering:

- start and len
  Or file_pos and num_bytes for other structures.

- disk_bytenr and disk_num_bytes
- offset and ram_bytes
- compression

So expect some seemingly unrelated line movement.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Qu Wenruo
87a6962f73 btrfs: export the expected file extent through can_nocow_extent()
Currently function can_nocow_extent() only returns members needed for
extent_map.

However since we will soon change the extent_map structure to be more
like btrfs_file_extent_item, we want to expose the expected file extent
caused by the NOCOW write for future usage.

This introduces a new structure, btrfs_file_extent, to be a more
memory access friendly representation of btrfs_file_extent_item.
And use that structure to expose the expected file extent caused by the
NOCOW write.

For now there is no user of the new structure yet.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Qu Wenruo
e8fe524da0 btrfs: rename extent_map::orig_block_len to disk_num_bytes
This would make it very obvious that the member just matches
btrfs_file_extent_item::disk_num_bytes.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Filipe Manana
8996f61ab9 btrfs: move fiemap code into its own file
Currently the core of the fiemap code lives in extent_io.c, which does
not make any sense because it's not related to extent IO at all (and it
was not as well before the big rewrite of fiemap I did some time ago).
The entry point for fiemap, btrfs_fiemap(), lives in inode.c since it's
an inode operation.

Since there's a significant amount of fiemap code, move all of it into a
dedicated file, including its entry point inode.c:btrfs_fiemap().

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Filipe Manana
f9763e4d15 btrfs: send: get rid of the label and gotos at ensure_commit_roots_uptodate()
Now that there is a helper to commit the current transaction and we are
using it, there's no need for the label and goto statements at
ensure_commit_roots_uptodate(). So replace them with direct return
statements that call btrfs_commit_current_transaction().

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Filipe Manana
ded980eb3f btrfs: add and use helper to commit the current transaction
We have several places that attach to the current transaction with
btrfs_attach_transaction_barrier() and then commit the transaction if
there is one. Add a helper and use it to deduplicate this pattern.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Filipe Manana
1f8aee2989 btrfs: scrub: avoid create/commit empty transaction at finish_extent_writes_for_zoned()
At finish_extent_writes_for_zoned() we use btrfs_join_transaction() to
catch any running transaction and then commit it. This will however create
a new and empty transaction in case there's no running transaction anymore
(got committed by the transaction kthread or other task for example) or
there's a running transaction finishing its commit and with a state >=
TRANS_STATE_UNBLOCKED. In the former case we don't need to do anything
while in the second case we just need to wait for the transaction to
complete its commit.

So improve this by using btrfs_attach_transaction_barrier() instead, which
does not create a new transaction if there's none running, and if there's
a current transaction that is committing, it will wait for it to fully
commit and not create a new transaction. This helps avoiding creating and
committing empty transactions, saving IO, time and unnecessary rotation of
the backup roots in the super block.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:20 +02:00
Filipe Manana
0557feab70 btrfs: send: avoid create/commit empty transaction at ensure_commit_roots_uptodate()
At ensure_commit_roots_uptodate() we use btrfs_join_transaction() to
catch any running transaction and then commit it. This will however create
a new and empty transaction in case there's no running transaction anymore
(got committed by the transaction kthread or other task for example) or
there's a running transaction finishing its commit and with a state >=
TRANS_STATE_UNBLOCKED. In the former case we don't need to do anything
while in the second case we just need to wait for the transaction to
complete its commit.

So improve this by using btrfs_attach_transaction_barrier() instead, which
does not create a new transaction if there's none running, and if there's
a current transaction that is committing, it will wait for it to fully
commit and not create a new transaction. This helps avoiding creating and
committing empty transactions, saving IO, time and unnecessary rotation of
the backup roots in the super block.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:19 +02:00
Filipe Manana
9e79c497f8 btrfs: send: make ensure_commit_roots_uptodate() simpler and more efficient
Before starting a send operation we have to make sure that every root has
its commit root matching the regular root, to that send doesn't find stale
inodes in the commit root (inodes that were deleted in the regular root)
and fails the inode lookups with -ESTALE.

Currently we keep looking for roots used by the send operation and as soon
as we find one we commit the current transaction (or a new one since
btrfs_join_transaction() creates one if there isn't any running or the
running one is in a state >= TRANS_STATE_UNBLOCKED). It's pointless to
keep looking until we don't find any, because after the first transaction
commit all the other roots are updated too, as they were already tagged in
the fs_info->fs_roots_radix radix tree when they were modified in order to
have a commit root different from the regular root.

Currently we are also always passing the main send root into
btrfs_join_transaction(), which despite not having any functional issue,
it is not optimal because in case the root wasn't modified we end up
adding it to fs_info->fs_roots_radix and then update its root item in the
root tree when committing the transaction, causing unnecessary work.

So simplify and make this more efficient by removing the looping and by
passing the first root we found that is modified as the argument to
btrfs_join_transaction().

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11 15:33:19 +02:00