btrfs/330, which tests our old trick to allow
mount -o ro,subvol=/x /dev/sda1 /foo
mount -o rw,subvol=/y /dev/sda1 /bar
fails on the block group tree. This is because we aren't preserving the
mount options for what is essentially a remount, and thus we're ending
up without the FREE_SPACE_TREE mount option, which triggers our free
space tree delete codepath. This isn't possible with the block group
tree and thus it falls over.
Fix this by making sure we copy the existing mount options for the
existing fs mount over in this case.
Fixes: f044b31867 ("btrfs: handle the ro->rw transition for mounting different subvolumes")
Reviewed-by: Neal Gompa <neal@gompa.dev>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's a warning in btrfs_issue_discard() when the range is not aligned
to 512 bytes, originally added in 4d89d377bb ("btrfs:
btrfs_issue_discard ensure offset/length are aligned to sector
boundaries"). We can't do sub-sector writes anyway so the adjustment is
the only thing that we can do and the warning is unnecessary.
CC: stable@vger.kernel.org # 4.19+
Reported-by: syzbot+4a4f1eba14eb5c3417d1@syzkaller.appspotmail.com
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The error message should accurately reflect the size rather than the
type.
Fixes: f82d1c7ca8 ("btrfs: tree-checker: Add EXTENT_ITEM and METADATA_ITEM check")
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Chung-Chiang Cheng <cccheng@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
If we have a filesystem with 4k sectorsize, and an inlined compressed
extent created like this:
item 4 key (257 INODE_ITEM 0) itemoff 15863 itemsize 160
generation 8 transid 8 size 4096 nbytes 4096
block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
sequence 1 flags 0x0(none)
item 5 key (257 INODE_REF 256) itemoff 15839 itemsize 24
index 2 namelen 14 name: source_inlined
item 6 key (257 EXTENT_DATA 0) itemoff 15770 itemsize 69
generation 8 type 0 (inline)
inline extent data size 48 ram_bytes 4096 compression 3 (zstd)
Then trying to reflink that extent in an aarch64 system with 64K page
size, the reflink would just fail:
# xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest
XFS_IOC_CLONE_RANGE: Input/output error
[CAUSE]
In zstd_decompress(), we didn't treat @start_byte as just a page offset,
but also use it as an indicator on whether we should error out, without
any proper explanation (this is copied from other decompression code).
In reality, for subpage cases, although @start_byte can be non-zero,
we should never switch input/output buffer nor error out, since the whole
input/output buffer should never exceed one sector, thus we should not
need to do any buffer switch.
Thus the current code using @start_byte as a condition to switch
input/output buffer or finish the decompression is completely incorrect.
[FIX]
The fix involves several modification:
- Rename @start_byte to @dest_pgoff to properly express its meaning
- Use @sectorsize other than PAGE_SIZE to properly initialize the
output buffer size
- Use correct destination offset inside the destination page
- Simplify the main loop
Since the input/output buffer should never switch, we only need one
zstd_decompress_stream() call.
- Consider early end as an error
After the fix, even on 64K page sized aarch64, above reflink now
works as expected:
# xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest
linked 4096/4096 bytes at offset 61440
And results the correct file layout:
item 9 key (258 INODE_ITEM 0) itemoff 15542 itemsize 160
generation 10 transid 10 size 65536 nbytes 4096
block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
sequence 1 flags 0x0(none)
item 10 key (258 INODE_REF 256) itemoff 15528 itemsize 14
index 3 namelen 4 name: dest
item 11 key (258 XATTR_ITEM 3817753667) itemoff 15445 itemsize 83
location key (0 UNKNOWN.0 0) type XATTR
transid 10 data_len 37 name_len 16
name: security.selinux
data unconfined_u:object_r:unlabeled_t:s0
item 12 key (258 EXTENT_DATA 61440) itemoff 15392 itemsize 53
generation 10 type 1 (regular)
extent data disk byte 13631488 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression 0 (none)
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
If we have a filesystem with 4k sectorsize, and an inlined compressed
extent created like this:
item 4 key (257 INODE_ITEM 0) itemoff 15863 itemsize 160
generation 8 transid 8 size 4096 nbytes 4096
block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
sequence 1 flags 0x0(none)
item 5 key (257 INODE_REF 256) itemoff 15839 itemsize 24
index 2 namelen 14 name: source_inlined
item 6 key (257 EXTENT_DATA 0) itemoff 15770 itemsize 69
generation 8 type 0 (inline)
inline extent data size 48 ram_bytes 4096 compression 2 (lzo)
Then trying to reflink that extent in an aarch64 system with 64K page
size, the reflink would just fail:
# xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest
XFS_IOC_CLONE_RANGE: Input/output error
[CAUSE]
In zlib_decompress(), we didn't treat @start_byte as just a page offset,
but also use it as an indicator on whether we should error out, without
any proper explanation (this is from the very beginning of btrfs).
In reality, for subpage cases, although @start_byte can be non-zero,
we should never switch input/output buffer nor error out, since the whole
input/output buffer should never exceed one sector.
Note: The above assumption is only not true if we're going to support
multi-page sectorsize.
Thus the current code using @start_byte as a condition to switch
input/output buffer or finish the decompression is completely incorrect.
[FIX]
The fix involves several modifications:
- Rename @start_byte to @dest_pgoff to properly express its meaning
- Use @sectorsize other than PAGE_SIZE to properly initialize the
output buffer size
- Use correct destination offset inside the destination page
- Use memcpy_to_page() to copy the contents to the destination page
- Use memzero_page() to zero out the tailing part
- Consider early end as an error
After the fix, even on 64K page sized aarch64, above reflink now
works as expected:
# xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest
linked 4096/4096 bytes at offset 61440
And results the correct file layout:
item 9 key (258 INODE_ITEM 0) itemoff 15542 itemsize 160
generation 10 transid 10 size 65536 nbytes 4096
block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
sequence 1 flags 0x0(none)
item 10 key (258 INODE_REF 256) itemoff 15528 itemsize 14
index 3 namelen 4 name: dest
item 11 key (258 XATTR_ITEM 3817753667) itemoff 15445 itemsize 83
location key (0 UNKNOWN.0 0) type XATTR
transid 10 data_len 37 name_len 16
name: security.selinux
data unconfined_u:object_r:unlabeled_t:s0
item 12 key (258 EXTENT_DATA 61440) itemoff 15392 itemsize 53
generation 10 type 1 (regular)
extent data disk byte 13631488 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression 0 (none)
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
If we have a filesystem with 4k sectorsize, and an inlined compressed
extent created like this:
item 4 key (257 INODE_ITEM 0) itemoff 15863 itemsize 160
generation 8 transid 8 size 4096 nbytes 4096
block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
sequence 1 flags 0x0(none)
item 5 key (257 INODE_REF 256) itemoff 15839 itemsize 24
index 2 namelen 14 name: source_inlined
item 6 key (257 EXTENT_DATA 0) itemoff 15770 itemsize 69
generation 8 type 0 (inline)
inline extent data size 48 ram_bytes 4096 compression 1 (zlib)
Which has an inline compressed extent at file offset 0, and its
decompressed size is 4K, allowing us to reflink that 4K range to another
location (which will not be compressed).
If we do such reflink on a subpage system, it would fail like this:
# xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest
XFS_IOC_CLONE_RANGE: Input/output error
[CAUSE]
In zlib_decompress(), we didn't treat @start_byte as just a page offset,
but also use it as an indicator on whether we should switch our output
buffer.
In reality, for subpage cases, although @start_byte can be non-zero,
we should never switch input/output buffer, since the whole input/output
buffer should never exceed one sector.
Note: The above assumption is only not true if we're going to support
multi-page sectorsize.
Thus the current code using @start_byte as a condition to switch
input/output buffer or finish the decompression is completely incorrect.
[FIX]
The fix involves several modifications:
- Rename @start_byte to @dest_pgoff to properly express its meaning
- Add an extra ASSERT() inside btrfs_decompress() to make sure the
input/output size never exceeds one sector.
- Use Z_FINISH flag to make sure the decompression happens in one go
- Remove the loop needed to switch input/output buffers
- Use correct destination offset inside the destination page
- Consider early end as an error
After the fix, even on 64K page sized aarch64, above reflink now
works as expected:
# xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest
linked 4096/4096 bytes at offset 61440
And resulted a correct file layout:
item 9 key (258 INODE_ITEM 0) itemoff 15542 itemsize 160
generation 10 transid 10 size 65536 nbytes 4096
block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
sequence 1 flags 0x0(none)
item 10 key (258 INODE_REF 256) itemoff 15528 itemsize 14
index 3 namelen 4 name: dest
item 11 key (258 XATTR_ITEM 3817753667) itemoff 15445 itemsize 83
location key (0 UNKNOWN.0 0) type XATTR
transid 10 data_len 37 name_len 16
name: security.selinux
data unconfined_u:object_r:unlabeled_t:s0
item 12 key (258 EXTENT_DATA 61440) itemoff 15392 itemsize 53
generation 10 type 1 (regular)
extent data disk byte 13631488 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression 0 (none)
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add extra sanity check for btrfs_ioctl_defrag_range_args::flags.
This is not really to enhance fuzzing tests, but as a preparation for
future expansion on btrfs_ioctl_defrag_range_args.
In the future we're going to add new members, allowing more fine tuning
for btrfs defrag. Without the -ENONOTSUPP error, there would be no way
to detect if the kernel supports those new defrag features.
CC: stable@vger.kernel.org # 4.14+
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>
Sweet Tea spotted a race between subvolume deletion and snapshotting
that can result in the root item for the snapshot having the
BTRFS_ROOT_SUBVOL_DEAD flag set. The race is:
Thread 1 | Thread 2
----------------------------------------------|----------
btrfs_delete_subvolume |
btrfs_set_root_flags(BTRFS_ROOT_SUBVOL_DEAD)|
|btrfs_mksubvol
| down_read(subvol_sem)
| create_snapshot
| ...
| create_pending_snapshot
| copy root item from source
down_write(subvol_sem) |
This flag is only checked in send and swap activate, which this would
cause to fail mysteriously.
create_snapshot() now checks the root refs to reject a deleted
subvolume, so we can fix this by locking subvol_sem earlier so that the
BTRFS_ROOT_SUBVOL_DEAD flag and the root refs are updated atomically.
CC: stable@vger.kernel.org # 4.14+
Reported-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The btrfs CI reported a lockdep warning as follows by running generic
generic/129.
WARNING: possible circular locking dependency detected
6.7.0-rc5+ #1 Not tainted
------------------------------------------------------
kworker/u5:5/793427 is trying to acquire lock:
ffff88813256d028 (&cache->lock){+.+.}-{2:2}, at: btrfs_zone_finish_one_bg+0x5e/0x130
but task is already holding lock:
ffff88810a23a318 (&fs_info->zone_active_bgs_lock){+.+.}-{2:2}, at: btrfs_zone_finish_one_bg+0x34/0x130
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&fs_info->zone_active_bgs_lock){+.+.}-{2:2}:
...
-> #0 (&cache->lock){+.+.}-{2:2}:
...
This is because we take fs_info->zone_active_bgs_lock after a block_group's
lock in btrfs_zone_activate() while doing the opposite in other places.
Fix the issue by expanding the fs_info->zone_active_bgs_lock's critical
section and taking it before a block_group's lock.
Fixes: a7e1ac7bdc ("btrfs: zoned: reserve zones for an active metadata/system block group")
CC: stable@vger.kernel.org # 6.6
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The error path of btrfs_get_chunk_map() releases
fs_info->mapping_tree_lock. But, it is taken and released in
btrfs_find_chunk_map(). So, there is no need to do so.
Fixes: 7dc66abb5a ("btrfs: use a dedicated data structure for chunk maps")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When compiling with gcc version 14.0.0 20231220 (experimental)
and W=1, I've noticed the following warning:
fs/btrfs/send.c: In function 'btrfs_ioctl_send':
fs/btrfs/send.c:8208:44: warning: 'kvcalloc' sizes specified with 'sizeof'
in the earlier argument and not in the later argument [-Wcalloc-transposed-args]
8208 | sctx->clone_roots = kvcalloc(sizeof(*sctx->clone_roots),
| ^
Since 'n' and 'size' arguments of 'kvcalloc()' are multiplied to
calculate the final size, their actual order doesn't affect the result
and so this is not a bug. But it's still worth to fix it.
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Writing sequentially to a huge file on btrfs on a SMR HDD revealed a
decline of the performance (220 MiB/s to 30 MiB/s after 500 minutes).
The performance goes down because of increased latency of the extent
allocation, which is induced by a traversing of a lot of full block groups.
So, this patch optimizes the ffe_ctl->hint_byte by choosing a block group
with sufficient size from the active block group list, which does not
contain full block groups.
After applying the patch, the performance is maintained well.
Fixes: 2eda57089e ("btrfs: zoned: implement sequential extent allocation")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Factor out prepare_allocation_zoned() for further extension. While at
it, optimize the if-branch a bit.
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>
Instead of passing three individual members of 'struct btrfs_io_geometry'
into btrfs_max_io_len(), pass a pointer to btrfs_io_geometry.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of passing three members of 'struct btrfs_io_geometry' into
set_io_stripe() pass a pointer to the whole structure and then get the needed
members out of btrfs_io_geometry.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Open code set_io_stripe() for RAID56, as it
a) uses a different method to calculate the stripe_index
b) doesn't need to go through raid-stripe-tree mapping code.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that all the per-profile if/else statement blocks have been
converted to calls to helper the conversion to switch/case is
straightforward.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have a container for the I/O geometry that has all the needed
information for the block mappings of SINGLE profiles, factor out a helper
calculating this information.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have a container for the I/O geometry that has all the needed
information for the block mappings of RAID5 and RAID6, factor out a helper
calculating this information.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reduce the scope of 'data_stripes' in btrfs_map_block(). While the
change alone may not make too much sense, it helps us factoring out a
helper function for the block mapping of RAID56 I/O.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have a container for the I/O geometry that has all the needed
information for the block mappings of RAID10, factor out a helper calculating
this information.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have a container for the I/O geometry that has all the needed
information for the block mappings of DUP, factor out a helper calculating
this information.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have a container for the I/O geometry that has all the needed
information for the block mappings of RAID1, factor out a helper calculating
this information.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have a container for the I/O geometry that has all the needed
information for the block mappings of RAID0, factor out a helper calculating
this information.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Re-introduce struct btrfs_io_geometry, holding the necessary bits and
pieces needed in btrfs_map_block() to decide the I/O geometry of a specific
block mapping.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The check in btrfs_map_block() deciding if a particular I/O is targeting a
single device is getting more and more convoluted.
Factor out the check conditions into a helper function, with no functional
change otherwise.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
Test case btrfs/124 failed if larger metadata folio is enabled, the
dying message looks like this:
BTRFS error (device dm-2): bad tree block start, mirror 2 want 31686656 have 0
BTRFS info (device dm-2): read error corrected: ino 0 off 31686656 (dev /dev/mapper/test-scratch2 sector 20928)
BUG: kernel NULL pointer dereference, address: 0000000000000020
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
CPU: 6 PID: 350881 Comm: btrfs Tainted: G OE 6.7.0-rc3-custom+ #128
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 2/2/2022
RIP: 0010:btrfs_read_extent_buffer+0x106/0x180 [btrfs]
PKRU: 55555554
Call Trace:
<TASK>
read_tree_block+0x33/0xb0 [btrfs]
read_block_for_search+0x23e/0x340 [btrfs]
btrfs_search_slot+0x2f9/0xe60 [btrfs]
btrfs_lookup_csum+0x75/0x160 [btrfs]
btrfs_lookup_bio_sums+0x21a/0x560 [btrfs]
btrfs_submit_chunk+0x152/0x680 [btrfs]
btrfs_submit_bio+0x1c/0x50 [btrfs]
submit_one_bio+0x40/0x80 [btrfs]
submit_extent_page+0x158/0x390 [btrfs]
btrfs_do_readpage+0x330/0x740 [btrfs]
extent_readahead+0x38d/0x6c0 [btrfs]
read_pages+0x94/0x2c0
page_cache_ra_unbounded+0x12d/0x190
relocate_file_extent_cluster+0x7c1/0x9d0 [btrfs]
relocate_block_group+0x2d3/0x560 [btrfs]
btrfs_relocate_block_group+0x2c7/0x4b0 [btrfs]
btrfs_relocate_chunk+0x4c/0x1a0 [btrfs]
btrfs_balance+0x925/0x13c0 [btrfs]
btrfs_ioctl+0x19f1/0x25d0 [btrfs]
__x64_sys_ioctl+0x90/0xd0
do_syscall_64+0x3f/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
[CAUSE]
The dying line is at btrfs_repair_io_failure() call inside
btrfs_repair_eb_io_failure().
The function is still relying on the extent buffer using page sized
folios.
When the extent buffer is using larger folio, we go into the 2nd slot of
folios[], and triggered the NULL pointer dereference.
[FIX]
Migrate btrfs_repair_io_failure() to folio interfaces.
So that when we hit a larger folio, we just submit the whole folio in
one go.
This also affects data repair path through btrfs_end_repair_bio(),
thankfully data is still fully page based, we can just add an
ASSERT(), and use page_folio() to convert the page to folio.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
Test case btrfs/002 would fail if larger folios are enabled for
metadata:
assertion failed: folio, in fs/btrfs/extent_io.c:4358
------------[ cut here ]------------
kernel BUG at fs/btrfs/extent_io.c:4358!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 30916 Comm: fsstress Tainted: G OE 6.7.0-rc3-custom+ #128
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 2/2/2022
RIP: 0010:assert_eb_folio_uptodate+0x98/0xe0 [btrfs]
Call Trace:
<TASK>
extent_buffer_test_bit+0x3c/0x70 [btrfs]
free_space_test_bit+0xcd/0x140 [btrfs]
modify_free_space_bitmap+0x27a/0x430 [btrfs]
add_to_free_space_tree+0x8d/0x160 [btrfs]
__btrfs_free_extent.isra.0+0xef1/0x13c0 [btrfs]
__btrfs_run_delayed_refs+0x786/0x13c0 [btrfs]
btrfs_run_delayed_refs+0x33/0x120 [btrfs]
btrfs_commit_transaction+0xa2/0x1350 [btrfs]
iterate_supers+0x77/0xe0
ksys_sync+0x60/0xa0
__do_sys_sync+0xa/0x20
do_syscall_64+0x3f/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
</TASK>
[CAUSE]
The function extent_buffer_test_bit() is not folio compatible.
It still assumes the old fixed page size, when an extent buffer with
large folio passed in, only eb->folios[0] is populated.
Then if the target bit range falls in the 2nd page of the folio, then we
would check eb->folios[1], and trigger the ASSERT().
[FIX]
Just migrate eb_bitmap_offset() to folio interfaces, using the
folio_size() to replace PAGE_SIZE.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If we still go the old page based iterator functions, like
bio_for_each_segment_all(), we can hit middle pages of a folio (compound
page).
In that case if we set any page flag on those middle pages, we can
easily trigger VM_BUG_ON(), as for compound page flags, they should
follow their flag policies (normally only set on leading or tail pages).
To avoid such problem in the future full folio migration, here we do:
- Change from bio_for_each_segment_all() to bio_for_each_folio_all()
This completely removes the ability to access the middle page.
- Add extra ASSERT()s for data read/write paths
To ensure we only get single paged folio for data now.
- Rename those end io functions to follow a certain schema
* end_bbio_compressed_read()
* end_bbio_compressed_write()
These two endio functions don't set any page flags, as they use pages
not mapped to any address space.
They can be very good candidates for higher order folio testing.
And they are shared between compression and encoded IO.
* end_bbio_data_read()
* end_bbio_data_write()
* end_bbio_meta_read()
* end_bbio_meta_write()
The old function names are not unified:
- end_bio_extent_writepage()
- end_bio_extent_readpage()
- extent_buffer_write_end_io()
- extent_buffer_read_end_io()
They share no schema on where the "end_*io" string should be, nor can
be confusing just using "extent_buffer" and "extent" to distinguish
data and metadata paths.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Although subpage itself is conflicting with higher folio, since subpage
(sectorsize < PAGE_SIZE and nodesize < PAGE_SIZE) means we will never
need higher order folio, there is a hidden pitfall:
- btrfs_page_*() helpers
Those helpers are an abstraction to handle both subpage and non-subpage
cases, which means we're going to pass pages pointers to those helpers.
And since those helpers are shared between data and metadata paths, it's
unavoidable to let them to handle folios, including higher order
folios).
Meanwhile for true subpage case, we should only have a single page
backed folios anyway, thus add a new ASSERT() for btrfs_subpage_assert()
to ensure that.
Also since those helpers are shared between both data and metadata, add
some extra ASSERT()s for data path to make sure we only get single page
backed folio for now.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These two functions are still using the old page based code, which is
not going to handle larger folios at all.
The migration itself is going to involve the following changes:
- PAGE_SIZE -> folio_size()
- PAGE_SHIFT -> folio_shift()
- get_eb_page_index() -> get_eb_folio_index()
- get_eb_offset_in_page() -> get_eb_offset_in_folio()
And since we're going to support larger folios, although above straight
conversion is good enough, this patch would add extra comments in the
involved functions to explain why the same single line code can now
cover 3 cases:
- folio_size == PAGE_SIZE, sectorsize == PAGE_SIZE, nodesize >= PAGE_SIZE
The common, non-subpage case with per-page folio.
- folio_size > PAGE_SIZE, sectorsize == PAGE_SIZE, nodesize >= PAGE_SIZE
The incoming larger folio, non-subpage case.
- folio_size == PAGE_SIZE, sectorsize < PAGE_SIZE, nodesize < PAGE_SIZE
The existing subpage case, we won't larger folio anyway.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This fixes as case in "btrfs: refactor alloc_extent_buffer() to
allocate-then-attach method".
We have been seeing panics in the CI for the subpage stuff recently, it
happens on btrfs/187 but could potentially happen anywhere.
In the subpage case, if we race with somebody else inserting the same
extent buffer, the error case will end up calling
detach_extent_buffer_page() on the page twice.
This is done first in the bit
for (int i = 0; i < attached; i++)
detach_extent_buffer_page(eb, eb->pages[i];
and then again in btrfs_release_extent_buffer().
This works fine for !subpage because we're the only person who ever has
ourselves on the private, and so when we do the initial
detach_extent_buffer_page() we know we've completely removed it.
However for subpage we could be using this page private elsewhere, so
this results in a double put on the subpage, which can result in an
early freeing.
The fix here is to clear eb->pages[i] for everything we detach. Then
anything still attached to the eb is freed in
btrfs_release_extent_buffer().
Because of this change we must update
btrfs_release_extent_buffer_pages() to not use num_extent_folios,
because it assumes eb->folio[0] is set properly. Since this is only
interested in freeing any pages we have on the extent buffer we can
simply use INLINE_EXTENT_BUFFER_PAGES.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Although we have migrated extent_buffer::pages[] to folios[], we're
still mostly using the folio_page() help to grab the page.
This patch would do the following cleanups for metadata:
- Introduce num_extent_folios() helper
This is to replace most num_extent_pages() callers.
- Use num_extent_folios() to iterate future large folios
This allows us to use things like
bio_add_folio()/bio_add_folio_nofail(), and only set the needed flags
for the folio (aka the leading/tailing page), which reduces the loop
iteration to 1 for large folios.
- Change metadata related functions to use folio pointers
Including their function name, involving:
* attach_extent_buffer_page()
* detach_extent_buffer_page()
* page_range_has_eb()
* btrfs_release_extent_buffer_pages()
* btree_clear_page_dirty()
* btrfs_page_inc_eb_refs()
* btrfs_page_dec_eb_refs()
- Change btrfs_is_subpage() to accept an address_space pointer
This is to allow both page->mapping and folio->mapping to be utilized.
As data is still using the old per-page code, and may keep so for a
while.
- Special corner case place holder for future order mismatches between
extent buffer and inode filemap
For now it's just a block of comments and a dead ASSERT(), no real
handling yet.
The subpage code would still go page, just because subpage and large
folio are conflicting conditions, thus we don't need to bother subpage
with higher order folios at all. Just folio_page(folio, 0) would be
enough.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor styling tweaks ]
Signed-off-by: David Sterba <dsterba@suse.com>
For now extent_buffer::pages[] are still only accepting single page
pointer, thus we can migrate to folios pretty easily.
As for single page, page and folio are 1:1 mapped, including their page
flags.
This patch would just do the conversion from struct page to struct
folio, providing the first step to higher order folio in the future.
This conversion is pretty simple:
- extent_buffer::pages[] -> extent_buffer::folios[]
- page_address(eb->pages[i]) -> folio_address(eb->pages[i])
- eb->pages[i] -> folio_page(eb->folios[i], 0)
There would be more specific cleanups preparing for the incoming higher
order folio support.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently alloc_extent_buffer() utilizes find_or_create_page() to
allocate one page a time for an extent buffer.
This method has the following disadvantages:
- find_or_create_page() is the legacy way of allocating new pages
With the new folio infrastructure, find_or_create_page() is just
redirected to filemap_get_folio().
- Lacks the way to support higher order (order >= 1) folios
As we can not yet let filemap give us a higher order folio.
This patch would change the workflow by the following way:
Old | new
-----------------------------------+-------------------------------------
| ret = btrfs_alloc_page_array();
for (i = 0; i < num_pages; i++) { | for (i = 0; i < num_pages; i++) {
p = find_or_create_page(); | ret = filemap_add_folio();
/* Attach page private */ | /* Reuse page cache if needed */
/* Reused eb if needed */ |
| /* Attach page private and
| reuse eb if needed */
| }
By this we split the page allocation and private attaching into two
parts, allowing future updates to each part more easily, and migrate to
folio interfaces (especially for possible higher order folios).
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value set as scrub_speed_max accepts size with suffixes
(k/m/g/t/p/e) but we should still validate it for trailing characters,
similar to what we do with chunk_size_store.
CC: stable@vger.kernel.org # 5.15+
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The radix-tree has been superseded by the xarray
(https://lwn.net/Articles/745073), this patch converts the
btrfs_root::delayed_nodes, the APIs are used in a simple way.
First idea is to do xa_insert() but this would require GFP_ATOMIC
allocation which we want to avoid if possible. The preload mechanism of
radix-tree can be emulated within the xarray API.
- xa_reserve() with GFP_NOFS outside of the lock, the reserved entry
is inserted atomically at most once
- xa_store() under a lock, in case something races in we can detect that
and xa_load() returns a valid pointer
All uses of xa_load() must check for a valid pointer in case they manage
to get between the xa_reserve() and xa_store(), this is handled in
btrfs_get_delayed_node().
Otherwise the functionality is equivalent, xarray implements the
radix-tree and there should be no performance difference.
The patch continues the efforts started in 253bf57555 ("btrfs: turn
delayed_nodes_tree into an XArray") and fixes the problems with locking
and GFP flags 088aea3b97 ("Revert "btrfs: turn delayed_nodes_tree
into an XArray"").
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The definition for btrfs_get_extent() is using "u64 end" as the last
parameter, but in implementation we go "u64 len", and all call sites
follows the implementation.
This can be very confusing during development, as most developers
including me, would just use the snippet returned by LSP (clangd in my
case), which would only check the definition.
Unfortunately this mismatch is introduced from the very beginning of
btrfs.
Fix it to prevent further confusion.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently, in struct extent_map, we use an unsigned int (32 bits) to
identify the compression type of an extent and an unsigned long (64 bits
on a 64 bits platform, 32 bits otherwise) for flags. We are only using
6 different flags, so an unsigned long is excessive and we can use flags
to identify the compression type instead of using a dedicated 32 bits
field.
We can easily have tens or hundreds of thousands (or more) of extent maps
on busy and large filesystems, specially with compression enabled or many
or large files with tons of small extents. So it's convenient to have the
extent_map structure as small as possible in order to use less memory.
So remove the compression type field from struct extent_map, use flags
to identify the compression type and shorten the flags field from an
unsigned long to a u32. This saves 8 bytes (on 64 bits platforms) and
reduces the size of the structure from 136 bytes down to 128 bytes, using
now only two cache lines, and increases the number of extent maps we can
have per 4K page from 30 to 32. By using a u32 for the flags instead of
an unsigned long, we no longer use test_bit(), set_bit() and clear_bit(),
but that level of atomicity is not needed as most flags are never cleared
once set (before adding an extent map to the tree), and the ones that can
be cleared or set after an extent map is added to the tree, are always
performed while holding the write lock on the extent map tree, while the
reader holds a lock on the tree or tests for a flag that never changes
once the extent map is in the tree (such as compression flags).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At mergable_maps() instead of having a single if statement with many
ORed and ANDed conditions, refactor it with multiple if statements that
check a single condition and return immediately once a requirement fails.
This makes it easier to read.
Also change the return type from int to bool, make the arguments const
and rename the function from mergable_maps() to mergeable_maps().
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The extent map pointer argument for extent_map_end() can be const as we
are not modifyng anything in the extent map. So make it const, as it will
allow further changes to callers that have a const extent map pointer.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When trying to merge an extent map that was just inserted or unpinned, we
will try to merge it with any adjacent extent map that is suitable.
However we will only check if our extent map is mergeable after searching
for the previous and next extent maps in the rbtree, meaning that we are
doing unnecessary calls to rb_prev() and rb_next() in case our extent map
is not mergeable (it's compressed, in the list of modifed extents, being
logged or pinned), wasting CPU time chasing rbtree pointers and pulling
in unnecessary cache lines.
So change the logic to check first if an extent map is mergeable before
searching for the next and previous extent maps in the rbtree.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At unpin_extent_range() we trigger a WARN_ON() when we don't find an
extent map or we find one with a start offset not matching the start
offset of the target range. This however isn't very useful for debugging
because:
1) We don't know which condition was triggered, as they are both in the
same WARN_ON() call;
2) We don't know which inode was affected, from which root, for which
range, what's the start offset of the extent map, and so on.
So trigger a separate warning for each case and log a message for each
case providing information about the inode, its root, the target range,
the generation and the start offset of the extent map we found.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At btrfs_add_extent_mapping(), in case add_extent_mapping() returned
-EEXIST, it's pointless to assign 0 to 'ret' since we will assign a value
to it shortly after, without 'ret' being used before that. So remove that
pointless assignment.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no need to export add_extent_mapping(), as it's only used inside
extent_map.c and in the self tests. For the tests we can use instead
btrfs_add_extent_mapping(), which will accomplish exactly the same as we
don't expect collisions in any of them. So unexport it and make the tests
use btrfs_add_extent_mapping() instead of add_extent_mapping().
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Some error messages of the extent map tests print decimal values of start
offsets and lengths, while other are oddly printing in hexadecimal, which
is far less human friendly, specially taking into consideration that all
the values are small and multiples of 4K, so it's a lot easier to read
them as decimal values. Change the format specifiers to print as decimal
instead.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Several of the extent map tests call btrfs_add_extent_mapping() which is
supposed to succeed and return an extent map through the pointer to
pointer argument. However the tests are deliberately ignoring a NULL
extent map, which is not expected to happen. So change the tests to error
out if a NULL extent map is found.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
