<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/include/trace/events/btrfs.h, branch v6.6.141</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.141</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.141'/>
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<updated>2026-04-27T13:23:25+00:00</updated>
<entry>
<title>btrfs: tracepoints: get correct superblock from dentry in event btrfs_sync_file()</title>
<updated>2026-04-27T13:23:25+00:00</updated>
<author>
<name>Goldwyn Rodrigues</name>
<email>rgoldwyn@suse.de</email>
</author>
<published>2026-03-13T18:11:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c09a7446aab5773f38d6abb25fce99b8e1dfbc97'/>
<id>urn:sha1:c09a7446aab5773f38d6abb25fce99b8e1dfbc97</id>
<content type='text'>
[ Upstream commit a85b46db143fda5869e7d8df8f258ccef5fa1719 ]

If overlay is used on top of btrfs, dentry-&gt;d_sb translates to overlay's
super block and fsid assignment will lead to a crash.

Use file_inode(file)-&gt;i_sb to always get btrfs_sb.

Reviewed-by: Boris Burkov &lt;boris@bur.io&gt;
Signed-off-by: Goldwyn Rodrigues &lt;rgoldwyn@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: fix NULL dereference on root when tracing inode eviction</title>
<updated>2026-03-25T10:05:58+00:00</updated>
<author>
<name>Miquel Sabaté Solà</name>
<email>mssola@mssola.com</email>
</author>
<published>2026-02-24T03:32:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=64d8abd8c5305795a2b35fc96039d99d34f5e762'/>
<id>urn:sha1:64d8abd8c5305795a2b35fc96039d99d34f5e762</id>
<content type='text'>
[ Upstream commit f157dd661339fc6f5f2b574fe2429c43bd309534 ]

When evicting an inode the first thing we do is to setup tracing for it,
which implies fetching the root's id. But in btrfs_evict_inode() the
root might be NULL, as implied in the next check that we do in
btrfs_evict_inode().

Hence, we either should set the -&gt;root_objectid to 0 in case the root is
NULL, or we move tracing setup after checking that the root is not
NULL. Setting the rootid to 0 at least gives us the possibility to trace
this call even in the case when the root is NULL, so that's the solution
taken here.

Fixes: 1abe9b8a138c ("Btrfs: add initial tracepoint support for btrfs")
Reported-by: syzbot+d991fea1b4b23b1f6bf8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d991fea1b4b23b1f6bf8
Signed-off-by: Miquel Sabaté Solà &lt;mssola@mssola.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
[ Adjust context ]
Signed-off-by: Bin Lan &lt;lanbincn@139.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>btrfs: constify more pointer parameters</title>
<updated>2025-08-28T14:28:41+00:00</updated>
<author>
<name>David Sterba</name>
<email>dsterba@suse.com</email>
</author>
<published>2025-08-19T02:27:53+00:00</published>
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<id>urn:sha1:d7badc2ba4da314da6a8947089929f53f10eb245</id>
<content type='text'>
[ Upstream commit ca283ea9920ac20ae23ed398b693db3121045019 ]

Continue adding const to 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.

Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>btrfs: correct the order of prelim_ref arguments in btrfs__prelim_ref</title>
<updated>2025-06-04T12:42:16+00:00</updated>
<author>
<name>Goldwyn Rodrigues</name>
<email>rgoldwyn@suse.de</email>
</author>
<published>2025-04-25T13:25:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7a97f961a568a8f72472dc804af02a0f73152c5f'/>
<id>urn:sha1:7a97f961a568a8f72472dc804af02a0f73152c5f</id>
<content type='text'>
[ Upstream commit bc7e0975093567f51be8e1bdf4aa5900a3cf0b1e ]

btrfs_prelim_ref() calls the old and new reference variables in the
incorrect order. This causes a NULL pointer dereference because oldref
is passed as NULL to trace_btrfs_prelim_ref_insert().

Note, trace_btrfs_prelim_ref_insert() is being called with newref as
oldref (and oldref as NULL) on purpose in order to print out
the values of newref.

To reproduce:
echo 1 &gt; /sys/kernel/debug/tracing/events/btrfs/btrfs_prelim_ref_insert/enable

Perform some writeback operations.

Backtrace:
BUG: kernel NULL pointer dereference, address: 0000000000000018
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 115949067 P4D 115949067 PUD 11594a067 PMD 0
 Oops: Oops: 0000 [#1] SMP NOPTI
 CPU: 1 UID: 0 PID: 1188 Comm: fsstress Not tainted 6.15.0-rc2-tester+ #47 PREEMPT(voluntary)  7ca2cef72d5e9c600f0c7718adb6462de8149622
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014
 RIP: 0010:trace_event_raw_event_btrfs__prelim_ref+0x72/0x130
 Code: e8 43 81 9f ff 48 85 c0 74 78 4d 85 e4 0f 84 8f 00 00 00 49 8b 94 24 c0 06 00 00 48 8b 0a 48 89 48 08 48 8b 52 08 48 89 50 10 &lt;49&gt; 8b 55 18 48 89 50 18 49 8b 55 20 48 89 50 20 41 0f b6 55 28 88
 RSP: 0018:ffffce44820077a0 EFLAGS: 00010286
 RAX: ffff8c6b403f9014 RBX: ffff8c6b55825730 RCX: 304994edf9cf506b
 RDX: d8b11eb7f0fdb699 RSI: ffff8c6b403f9010 RDI: ffff8c6b403f9010
 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000010
 R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8c6b4e8fb000
 R13: 0000000000000000 R14: ffffce44820077a8 R15: ffff8c6b4abd1540
 FS:  00007f4dc6813740(0000) GS:ffff8c6c1d378000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000018 CR3: 000000010eb42000 CR4: 0000000000750ef0
 PKRU: 55555554
 Call Trace:
  &lt;TASK&gt;
  prelim_ref_insert+0x1c1/0x270
  find_parent_nodes+0x12a6/0x1ee0
  ? __entry_text_end+0x101f06/0x101f09
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? srso_alias_return_thunk+0x5/0xfbef5
  btrfs_is_data_extent_shared+0x167/0x640
  ? fiemap_process_hole+0xd0/0x2c0
  extent_fiemap+0xa5c/0xbc0
  ? __entry_text_end+0x101f05/0x101f09
  btrfs_fiemap+0x7e/0xd0
  do_vfs_ioctl+0x425/0x9d0
  __x64_sys_ioctl+0x75/0xc0

Signed-off-by: Goldwyn Rodrigues &lt;rgoldwyn@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: zoned: fix zone_unusable accounting on making block group read-write again</title>
<updated>2024-08-11T10:47:24+00:00</updated>
<author>
<name>Naohiro Aota</name>
<email>naohiro.aota@wdc.com</email>
</author>
<published>2023-02-15T00:18:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ae29e6f764f6f72368dc6d0cc7386f73d579cd55'/>
<id>urn:sha1:ae29e6f764f6f72368dc6d0cc7386f73d579cd55</id>
<content type='text'>
commit 8cd44dd1d17a23d5cc8c443c659ca57aa76e2fa5 upstream.

When btrfs makes a block group read-only, it adds all free regions in the
block group to space_info-&gt;bytes_readonly. That free space excludes
reserved and pinned regions. OTOH, when btrfs makes the block group
read-write again, it moves all the unused regions into the block group's
zone_unusable. That unused region includes reserved and pinned regions.
As a result, it counts too much zone_unusable bytes.

Fortunately (or unfortunately), having erroneous zone_unusable does not
affect the calculation of space_info-&gt;bytes_readonly, because free
space (num_bytes in btrfs_dec_block_group_ro) calculation is done based on
the erroneous zone_unusable and it reduces the num_bytes just to cancel the
error.

This behavior can be easily discovered by adding a WARN_ON to check e.g,
"bg-&gt;pinned &gt; 0" in btrfs_dec_block_group_ro(), and running fstests test
case like btrfs/282.

Fix it by properly considering pinned and reserved in
btrfs_dec_block_group_ro(). Also, add a WARN_ON and introduce
btrfs_space_info_update_bytes_zone_unusable() to catch a similar mistake.

Fixes: 169e0da91a21 ("btrfs: zoned: track unusable bytes for zones")
CC: stable@vger.kernel.org # 5.15+
Signed-off-by: Naohiro Aota &lt;naohiro.aota@wdc.com&gt;
Reviewed-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>btrfs: remove v0 extent handling</title>
<updated>2023-08-21T12:54:48+00:00</updated>
<author>
<name>Qu Wenruo</name>
<email>wqu@suse.com</email>
</author>
<published>2023-08-11T11:02:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=182741d287fb1ea870ee6ef45aa1915a0b031233'/>
<id>urn:sha1:182741d287fb1ea870ee6ef45aa1915a0b031233</id>
<content type='text'>
The v0 extent item has been deprecated for a long time, and we don't have
any report from the community either.

So it's time to remove the v0 extent specific error handling, and just
treat them as regular extent tree corruption.

This patch would remove the btrfs_print_v0_err() helper, and enhance the
involved error handling to treat them just as any extent tree
corruption. No reports regarding v0 extents have been seen since the
graceful handling was added in 2018.

This involves:

- btrfs_backref_add_tree_node()
  This change is a little tricky, the new code is changed to only handle
  BTRFS_TREE_BLOCK_REF_KEY and BTRFS_SHARED_BLOCK_REF_KEY.

  But this is safe, as we have rejected any unknown inline refs through
  btrfs_get_extent_inline_ref_type().
  For keyed backrefs, we're safe to skip anything we don't know (that's
  if it can pass tree-checker in the first place).

- btrfs_lookup_extent_info()
- lookup_inline_extent_backref()
- run_delayed_extent_op()
- __btrfs_free_extent()
- add_tree_block()
  Regular error handling of unexpected extent tree item, and abort
  transaction (if we have a trans handle).

- remove_extent_data_ref()
  It's pretty much the same as the regular rejection of unknown backref
  key.
  But for this particular case, we can also remove a BUG_ON().

- extent_data_ref_count()
  We can remove the BTRFS_EXTENT_REF_V0_KEY BUG_ON(), as it would be
  rejected by the only caller.

- btrfs_print_leaf()
  Remove the handling for BTRFS_EXTENT_REF_V0_KEY.

Signed-off-by: Qu Wenruo &lt;wqu@suse.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: tracepoints: simplify raid56 events</title>
<updated>2023-08-21T12:52:12+00:00</updated>
<author>
<name>Qu Wenruo</name>
<email>wqu@suse.com</email>
</author>
<published>2023-06-20T07:06:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=dbb6ecb328cb5f974ff0a04ad31af332be5a122f'/>
<id>urn:sha1:dbb6ecb328cb5f974ff0a04ad31af332be5a122f</id>
<content type='text'>
After commit 6bfd0133bee2 ("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 &lt;wqu@suse.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: tracepoints: also show actual number of the outstanding extents</title>
<updated>2023-06-19T17:47:58+00:00</updated>
<author>
<name>Naohiro Aota</name>
<email>naohiro.aota@wdc.com</email>
</author>
<published>2023-06-19T02:15:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=6442550027f77a76efa7873b946c34c4a733febd'/>
<id>urn:sha1:6442550027f77a76efa7873b946c34c4a733febd</id>
<content type='text'>
The btrfs_inode_mod_outstanding_extents trace event only shows the modified
number to the number of outstanding extents. It would be helpful if we can
see the resulting extent number as well.

Signed-off-by: Naohiro Aota &lt;naohiro.aota@wdc.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: add a btrfs_finish_ordered_extent helper</title>
<updated>2023-06-19T11:59:37+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2023-05-31T07:54:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=122e9ede5355071359c10a8ebca138b162ef176b'/>
<id>urn:sha1:122e9ede5355071359c10a8ebca138b162ef176b</id>
<content type='text'>
Add a helper to complete an ordered_extent without first doing a lookup.
The tracepoint cannot use the ordered_extent class as we also want to
print the range.

Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Reviewed-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: replace btrfs_io_context::raid_map with a fixed u64 value</title>
<updated>2023-04-17T16:01:14+00:00</updated>
<author>
<name>Qu Wenruo</name>
<email>wqu@suse.com</email>
</author>
<published>2023-02-17T05:37:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=18d758a2d81a97b9a54a37d535870ce3170cc208'/>
<id>urn:sha1:18d758a2d81a97b9a54a37d535870ce3170cc208</id>
<content type='text'>
In btrfs_io_context structure, we have a pointer raid_map, which
indicates the logical bytenr for each stripe.

But considering we always call sort_parity_stripes(), the result
raid_map[] is always sorted, thus raid_map[0] is always the logical
bytenr of the full stripe.

So why we waste the space and time (for sorting) for raid_map?

This patch will replace btrfs_io_context::raid_map with a single u64
number, full_stripe_start, by:

- Replace btrfs_io_context::raid_map with full_stripe_start

- Replace call sites using raid_map[0] to use full_stripe_start

- Replace call sites using raid_map[i] to compare with nr_data_stripes.

The benefits are:

- Less memory wasted on raid_map
  It's sizeof(u64) * num_stripes vs sizeof(u64).
  It'll always save at least one u64, and the benefit grows larger with
  num_stripes.

- No more weird alloc_btrfs_io_context() behavior
  As there is only one fixed size + one variable length array.

Signed-off-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
</feed>
