btrfs: compression: adjust cb->compressed_folios allocation type

In preparation for making the kmalloc() family of allocators type aware,
we need to make sure that the returned type from the allocat

btrfs: compression: adjust cb->compressed_folios allocation type

In preparation for making the kmalloc() family of allocators type aware,
we need to make sure that the returned type from the allocation matches
the type of the variable being assigned. (Before, the allocator would
always return "void *", which can be implicitly cast to any pointer type.)

The assigned type is "struct folio **" but the returned type will be
"struct page **". These are the same allocation size (pointer size), but
the types don't match. Adjust the allocation type to match the assignment.

Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: defrag: extend ioctl to accept compression levels

The zstd and zlib compression types support setting compression levels.
Enhance the defrag interface to specify the levels as well. For zstd

btrfs: defrag: extend ioctl to accept compression levels

The zstd and zlib compression types support setting compression levels.
Enhance the defrag interface to specify the levels as well. For zstd the
negative (realtime) levels are also accepted.

Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Daniel Vacek <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: zstd: enable negative compression levels mount option

Allow using the fast modes (negative compression levels) of zstd as a
mount option.

As per the results, the compression ratio is (expect

btrfs: zstd: enable negative compression levels mount option

Allow using the fast modes (negative compression levels) of zstd as a
mount option.

As per the results, the compression ratio is (expectedly) lower:

for level in {-15..-1} 1 2 3; \
do printf "level %3d\n" $level; \
mount -o compress=zstd:$level /dev/sdb /mnt/test/; \
grep sdb /proc/mounts; \
cp -r /usr/bin /mnt/test/; sync; compsize /mnt/test/bin; \
cp -r /usr/share/doc /mnt/test/; sync; compsize /mnt/test/doc; \
cp enwik9 /mnt/test/; sync; compsize /mnt/test/enwik9; \
cp linux-6.13.tar /mnt/test/; sync; compsize /mnt/test/linux-6.13.tar; \
rm -r /mnt/test/{bin,doc,enwik9,linux-6.13.tar}; \
umount /mnt/test/; \
done |& tee results | \
awk '/^level/{print}/^TOTAL/{print$3"\t"$2" |"}' | paste - - - - -

266M bin | 45M doc | 953M wiki | 1.4G source
=============================+===============+===============+===============+
level -15 180M 67% | 30M 68% | 694M 72% | 598M 40% |
level -14 180M 67% | 30M 67% | 683M 71% | 581M 39% |
level -13 177M 66% | 29M 66% | 671M 70% | 566M 38% |
level -12 174M 65% | 29M 65% | 658M 69% | 548M 37% |
level -11 174M 65% | 28M 64% | 645M 67% | 530M 35% |
level -10 171M 64% | 28M 62% | 631M 66% | 512M 34% |
level -9 165M 62% | 27M 61% | 615M 64% | 493M 33% |
level -8 161M 60% | 27M 59% | 598M 62% | 475M 32% |
level -7 155M 58% | 26M 58% | 582M 61% | 457M 30% |
level -6 151M 56% | 25M 56% | 565M 59% | 437M 29% |
level -5 145M 54% | 24M 55% | 545M 57% | 417M 28% |
level -4 139M 52% | 23M 52% | 520M 54% | 391M 26% |
level -3 135M 50% | 22M 50% | 495M 51% | 369M 24% |
level -2 127M 47% | 22M 48% | 470M 49% | 349M 23% |
level -1 120M 45% | 21M 47% | 452M 47% | 332M 22% |
level 1 110M 41% | 17M 39% | 362M 38% | 290M 19% |
level 2 106M 40% | 17M 38% | 349M 36% | 288M 19% |
level 3 104M 39% | 16M 37% | 340M 35% | 276M 18% |

The samples represent some data sets that can be commonly found and show
approximate compressibility. The fast levels trade off speed for ratio
and are best suitable for highly compressible data.

As can be seen above, comparing the results to the current default zstd
level 3, the negative levels are roughly 2x worse at -15 and the
ratio increases almost linearly with each level.

Signed-off-by: Daniel Vacek <[email protected]>
[ update changelog ]
Signed-off-by: David Sterba <[email protected]>

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btrfs: use filemap_get_folio() helper

When fgp_flags and gfp_flags are zero, use filemap_get_folio(A, B)
instead of __filemap_get_folio(A, B, 0, 0)—no need for the extra
arguments 0, 0.

Signed-off-

btrfs: use filemap_get_folio() helper

When fgp_flags and gfp_flags are zero, use filemap_get_folio(A, B)
instead of __filemap_get_folio(A, B, 0, 0)—no need for the extra
arguments 0, 0.

Signed-off-by: Anand Jain <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: rename btrfs_folio_(set|start|end)_writer_lock()

Since there is no user of reader locks, rename the writer locks into a
more generic name, by removing the "_writer" part from the name.

And a

btrfs: rename btrfs_folio_(set|start|end)_writer_lock()

Since there is no user of reader locks, rename the writer locks into a
more generic name, by removing the "_writer" part from the name.

And also rename btrfs_subpage::writer into btrfs_subpage::locked.

Signed-off-by: Qu Wenruo <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: unify to use writer locks for subpage locking

Since commit d7172f52e993 ("btrfs: use per-buffer locking for
extent_buffer reading"), metadata read no longer relies on the subpage
reader locki

btrfs: unify to use writer locks for subpage locking

Since commit d7172f52e993 ("btrfs: use per-buffer locking for
extent_buffer reading"), metadata read no longer relies on the subpage
reader locking.

This means we do not need to maintain a different metadata/data split
for locking, so we can convert the existing reader lock users by:

- add_ra_bio_pages()
Convert to btrfs_folio_set_writer_lock()

- end_folio_read()
Convert to btrfs_folio_end_writer_lock()

- begin_folio_read()
Convert to btrfs_folio_set_writer_lock()

- folio_range_has_eb()
Remove the subpage->readers checks, since it is always 0.

- Remove btrfs_subpage_start_reader() and btrfs_subpage_end_reader()

Signed-off-by: Qu Wenruo <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: drop unused parameter level from alloc_heuristic_ws()

The compression heuristic pass does not need a level, so we can drop the
parameter.

Reviewed-by: Anand Jain <[email protected]>
Sign

btrfs: drop unused parameter level from alloc_heuristic_ws()

The compression heuristic pass does not need a level, so we can drop the
parameter.

Reviewed-by: Anand Jain <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: lzo: drop unused paramter level from lzo_alloc_workspace()

The LZO compression has only one level, we don't need to pass the
parameter.

Reviewed-by: Anand Jain <[email protected]>
Signed

btrfs: lzo: drop unused paramter level from lzo_alloc_workspace()

The LZO compression has only one level, we don't need to pass the
parameter.

Reviewed-by: Anand Jain <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: compression: add an ASSERT() to ensure the read-in length is sane

There are already two bugs (one in zlib, one in zstd) that involved
compression path is not handling sector size < page size

btrfs: compression: add an ASSERT() to ensure the read-in length is sane

There are already two bugs (one in zlib, one in zstd) that involved
compression path is not handling sector size < page size cases well.

So it makes more sense to make sure that btrfs_compress_folios() returns

Since we already have two bugs (one in zlib, one in zstd) in the
compression path resulting the @total_in be to larger than the
to-be-compressed range length, there is enough reason to add an ASSERT()
to make sure the total read-in length doesn't exceed the input length.

Signed-off-by: Qu Wenruo <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: convert btrfs_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and f

btrfs: convert btrfs_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. Based on the previous patch, the compression path can be
directly used in folio without converting to page.

Signed-off-by: Li Zetao <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: convert zstd_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and fo

btrfs: convert zstd_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. And memcpy_to_page() can be replaced with memcpy_to_folio().
But there is no memzero_folio(), but it can be replaced equivalently by
folio_zero_range().

Signed-off-by: Li Zetao <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

show more ...

btrfs: convert lzo_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and fol

btrfs: convert lzo_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. And memcpy_to_page() can be replaced with memcpy_to_folio().
But there is no memzero_folio(), but it can be replaced equivalently by
folio_zero_range().

Signed-off-by: Li Zetao <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

show more ...

btrfs: convert zlib_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and fo

btrfs: convert zlib_decompress() to take a folio

The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. And memcpy_to_page() can be replaced with memcpy_to_folio().
But there is no memzero_folio(), but it can be replaced equivalently by
folio_zero_range().

Signed-off-by: Li Zetao <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

show more ...

btrfs: do not hold the extent lock for entire read

Historically we've held the extent lock throughout the entire read.
There's been a few reasons for this, but it's mostly just caused us
problems.

btrfs: do not hold the extent lock for entire read

Historically we've held the extent lock throughout the entire read.
There's been a few reasons for this, but it's mostly just caused us
problems. For example, this prevents us from allowing page faults
during direct io reads, because we could deadlock. This has forced us
to only allow 4k reads at a time for io_uring NOWAIT requests because we
have no idea if we'll be forced to page fault and thus have to do a
whole lot of work.

On the buffered side we are protected by the page lock, as long as we're
reading things like buffered writes, punch hole, and even direct IO to a
certain degree will get hung up on the page lock while the page is in
flight.

On the direct side we have the dio extent lock, which acts much like the
way the extent lock worked previously to this patch, however just for
direct reads. This protects direct reads from concurrent direct writes,
while we're protected from buffered writes via the inode lock.

Now that we're protected in all cases, narrow the extent lock to the
part where we're getting the extent map to submit the reads, no longer
holding the extent lock for the entire read operation. Push the extent
lock down into do_readpage() so that we're only grabbing it when looking
up the extent map. This portion was contributed by Goldwyn.

Co-developed-by: Goldwyn Rodrigues <[email protected]>
Reviewed-by: Goldwyn Rodrigues <[email protected]>
Signed-off-by: Josef Bacik <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: rename btrfs_submit_bio() to btrfs_submit_bbio()

The function name is a bit misleading as it submits the btrfs_bio
(bbio), rename it so we can use btrfs_submit_bio() when an actual bio is
sub

btrfs: rename btrfs_submit_bio() to btrfs_submit_bbio()

The function name is a bit misleading as it submits the btrfs_bio
(bbio), rename it so we can use btrfs_submit_bio() when an actual bio is
submitted.

Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: David Sterba <[email protected]>

show more ...

btrfs: convert add_ra_bio_pages() to use only folios

Willy is going to get rid of page->index, and add_ra_bio_pages uses
page->index. Make his life easier by converting add_ra_bio_pages to use
foli

btrfs: convert add_ra_bio_pages() to use only folios

Willy is going to get rid of page->index, and add_ra_bio_pages uses
page->index. Make his life easier by converting add_ra_bio_pages to use
folios so that we are no longer using page->index.

Signed-off-by: Josef Bacik <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: fix extent map use-after-free when adding pages to compressed bio

At add_ra_bio_pages() we are accessing the extent map to calculate
'add_size' after we dropped our reference on the extent ma

btrfs: fix extent map use-after-free when adding pages to compressed bio

At add_ra_bio_pages() we are accessing the extent map to calculate
'add_size' after we dropped our reference on the extent map, resulting
in a use-after-free. Fix this by computing 'add_size' before dropping our
extent map reference.

Reported-by: [email protected]
Link: https://lore.kernel.org/linux-btrfs/[email protected]/
Fixes: 6a4049102055 ("btrfs: subpage: make add_ra_bio_pages() compatible")
CC: [email protected] # 6.1+
Signed-off-by: Filipe Manana <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: remove the extra_gfp parameter from btrfs_alloc_folio_array()

The function btrfs_alloc_folio_array() is only utilized in
btrfs_submit_compressed_read() and no other location, and the only
cal

btrfs: remove the extra_gfp parameter from btrfs_alloc_folio_array()

The function btrfs_alloc_folio_array() is only utilized in
btrfs_submit_compressed_read() and no other location, and the only
caller is not utilizing the @extra_gfp parameter.

Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Qu Wenruo <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: pass a btrfs_inode to btrfs_compress_heuristic()

Pass a struct btrfs_inode to btrfs_compress_heuristic() as it's an
internal interface, allowing to remove some use of BTRFS_I.

Reviewed-by: B

btrfs: pass a btrfs_inode to btrfs_compress_heuristic()

Pass a struct btrfs_inode to btrfs_compress_heuristic() as it's an
internal interface, allowing to remove some use of BTRFS_I.

Reviewed-by: Boris Burkov <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: switch btrfs_ordered_extent::inode to struct btrfs_inode

The structure is internal so we should use struct btrfs_inode for that,
allowing to remove some use of BTRFS_I.

Reviewed-by: Boris Bu

btrfs: switch btrfs_ordered_extent::inode to struct btrfs_inode

The structure is internal so we should use struct btrfs_inode for that,
allowing to remove some use of BTRFS_I.

Reviewed-by: Boris Burkov <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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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

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 <[email protected]>
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Qu Wenruo <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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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 sanit

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 <[email protected]>
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Qu Wenruo <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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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 th

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 <[email protected]>
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Qu Wenruo <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: fix misspelled end IO compression callbacks

Fix typo in the end IO compression callbacks, from "comprssed" to
"compressed".

Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana

btrfs: fix misspelled end IO compression callbacks

Fix typo in the end IO compression callbacks, from "comprssed" to
"compressed".

Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>

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btrfs: change root->root_key.objectid to btrfs_root_id()

A comment from Filipe on one of my previous cleanups brought my
attention to a new helper we have for getting the root id of a root,
which ma

btrfs: change root->root_key.objectid to btrfs_root_id()

A comment from Filipe on one of my previous cleanups brought my
attention to a new helper we have for getting the root id of a root,
which makes it easier to read in the code.

The changes where made with the following Coccinelle semantic patch:

// <smpl>
@@
expression E,E1;
@@
(
E->root_key.objectid = E1
|
- E->root_key.objectid
+ btrfs_root_id(E)
)
// </smpl>

Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Josef Bacik <[email protected]>
Reviewed-by: David Sterba <[email protected]>
[ minor style fixups ]
Signed-off-by: David Sterba <[email protected]>

show more ...