btrfs: zlib: fix and simplify the inline extent decompression

[ Upstream commit 2c25716dcc25a0420c4ad49d6e6bf61e60a21434 ]

[BUG]

If we have a filesystem with 4k sectorsize, and an inlined compress

btrfs: zlib: fix and simplify the inline extent decompression

[ Upstream commit 2c25716dcc25a0420c4ad49d6e6bf61e60a21434 ]

[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>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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

commit 8e7860543a94784d744c7ce34b78a2e11beefa5c upstream.

At add_ra_bio_pages() we are accessing the extent map to calculate

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

commit 8e7860543a94784d744c7ce34b78a2e11beefa5c upstream.

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: syzbot+853d80cba98ce1157ae6@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000038144061c6d18f2@google.com/
Fixes: 6a4049102055 ("btrfs: subpage: make add_ra_bio_pages() compatible")
CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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btrfs: make btrfs_compressed_bioset static

The 'btrfs_compressed_bioset' struct isn't exported outside of the
fs/btrfs/compression.c file, so make it static to fix the following
sparse warning:

fs/

btrfs: make btrfs_compressed_bioset static

The 'btrfs_compressed_bioset' struct isn't exported outside of the
fs/btrfs/compression.c file, so make it static to fix the following
sparse warning:

fs/btrfs/compression.c:40:16: warning: symbol 'btrfs_compressed_bioset' was not declared. Should it be static?

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: use btrfs_finish_ordered_extent to complete compressed writes

Use the btrfs_finish_ordered_extent helper to complete compressed writes
using the bbio->ordered pointer instead of requiring an

btrfs: use btrfs_finish_ordered_extent to complete compressed writes

Use the btrfs_finish_ordered_extent helper to complete compressed writes
using the bbio->ordered pointer instead of requiring an rbtree lookup
in the otherwise equivalent btrfs_mark_ordered_io_finished called from
btrfs_writepage_endio_finish_ordered.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: add an ordered_extent pointer to struct btrfs_bio

Add a pointer to the ordered_extent to the existing union in struct
btrfs_bio, so all code dealing with data write bios can just use a
pointe

btrfs: add an ordered_extent pointer to struct btrfs_bio

Add a pointer to the ordered_extent to the existing union in struct
btrfs_bio, so all code dealing with data write bios can just use a
pointer dereference to retrieve the ordered_extent instead of doing
multiple rbtree lookups per I/O.

The reference to this ordered_extent is dropped at end I/O time,
which implies that an extra one must be acquired when the bio is split.
This also requires moving the btrfs_extract_ordered_extent call into
btrfs_split_bio so that the invariant of always having a valid
ordered_extent reference for the btrfs_bio is kept.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: pass an ordered_extent to btrfs_submit_compressed_write

btrfs_submit_compressed_write always operates on a single ordered_extent.
Make that explicit by using btrfs_alloc_ordered_extent in the

btrfs: pass an ordered_extent to btrfs_submit_compressed_write

btrfs_submit_compressed_write always operates on a single ordered_extent.
Make that explicit by using btrfs_alloc_ordered_extent in the callers
and passing the ordered_extent to btrfs_submit_compressed_write. This
will help with storing and ordered_extent pointer in the btrfs_bio in
subsequent patches.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: limit write bios to a single ordered extent

Currently buffered writeback bios are allowed to span multiple
ordered_extents, although that basically never actually happens since
commit 4a445b7

btrfs: limit write bios to a single ordered extent

Currently buffered writeback bios are allowed to span multiple
ordered_extents, although that basically never actually happens since
commit 4a445b7b6178 ("btrfs: don't merge pages into bio if their page
offset is not contiguous").

Supporting bios than span ordered_extents complicates the file
checksumming code, and prevents us from adding an ordered_extent pointer
to the btrfs_bio structure. Use the existing code to limit a bio to
single ordered_extent for zoned device writes for all writes.

This allows to remove the REQ_BTRFS_ONE_ORDERED flags, and the
handling of multiple ordered_extents in btrfs_csum_one_bio.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: stop setting PageError in the data I/O path

PageError is not used by the VFS/MM and deprecated because it uses up a
page bit and has no coherent rules. Instead read errors are usually
propag

btrfs: stop setting PageError in the data I/O path

PageError is not used by the VFS/MM and deprecated because it uses up a
page bit and has no coherent rules. Instead read errors are usually
propagated by not setting or clearing the uptodate bit, and write errors
are propagated through the address_space. Btrfs now only sets the flag
and never clears it for data pages, so just remove all places setting it,
and the subpage error bit.

Note that the error propagation for superblock writes that work on the
block device mapping still uses PageError for now, but that will be
addressed in a separate series.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: remove the mirror_num argument to btrfs_submit_compressed_read

Given that read recovery for data I/O is handled in the storage layer,
the mirror_num argument to btrfs_submit_compressed_read i

btrfs: remove the mirror_num argument to btrfs_submit_compressed_read

Given that read recovery for data I/O is handled in the storage layer,
the mirror_num argument to btrfs_submit_compressed_read is always 0,
so remove it.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: use SECTOR_SHIFT to convert physical offset to LBA

Use SECTOR_SHIFT while converting a physical address to an LBA, makes
it more readable.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
R

btrfs: use SECTOR_SHIFT to convert physical offset to LBA

Use SECTOR_SHIFT while converting a physical address to an LBA, makes
it more readable.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: introduce btrfs_bio::fs_info member

Currently we're doing a lot of work for btrfs_bio:

- Checksum verification for data read bios
- Bio splits if it crosses stripe boundary
- Read repair for

btrfs: introduce btrfs_bio::fs_info member

Currently we're doing a lot of work for btrfs_bio:

- Checksum verification for data read bios
- Bio splits if it crosses stripe boundary
- Read repair for data read bios

However for the incoming scrub patches, we don't want this extra
functionality at all, just plain logical + mirror -> physical mapping
ability.

Thus here we do the following changes:

- Introduce btrfs_bio::fs_info
This is for the new scrub specific btrfs_bio, which would not populate
btrfs_bio::inode.
Thus we need such new member to grab a fs_info

This new member will always be populated.

- Replace @inode argument with @fs_info for btrfs_bio_init() and its
caller
Since @inode is no longer a mandatory member, replace it with
@fs_info, and let involved users populate @inode.

- Skip checksum verification and generation if @bbio->inode is NULL

- Add extra ASSERT()s
To make sure:

* bbio->inode is properly set for involved read repair path
* if @file_offset is set, bbio->inode is also populated

- Grab @fs_info from @bbio directly
We can no longer go @bbio->inode->root->fs_info, as bbio->inode can be
NULL. This involves:

* btrfs_simple_end_io()
* should_async_write()
* btrfs_wq_submit_bio()
* btrfs_use_zone_append()

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: move kthread_associate_blkcg out of btrfs_submit_compressed_write

btrfs_submit_compressed_write should not have to care if it is called
from a helper thread or not. Move the kthread_associat

btrfs: move kthread_associate_blkcg out of btrfs_submit_compressed_write

btrfs_submit_compressed_write should not have to care if it is called
from a helper thread or not. Move the kthread_associate_blkcg handling
into submit_one_async_extent, as that is the one caller that needs it.
Also move the assignment of REQ_CGROUP_PUNT into cow_file_range_async,
as that is the routine that sets up the helper thread offload.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: simplify adding pages in btrfs_add_compressed_bio_pages

btrfs_add_compressed_bio_pages is needlessly complicated. Instead
of iterating over the logic disk offset just to add pages to the bio

btrfs: simplify adding pages in btrfs_add_compressed_bio_pages

btrfs_add_compressed_bio_pages is needlessly complicated. Instead
of iterating over the logic disk offset just to add pages to the bio
use a simple offset starting at 0, which also removes most of the
claiming. Additionally __bio_add_pages already takes care of the
assert that the bio is always properly sized, and btrfs_submit_bio
called right after asserts that the bio size is non-zero.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: move the bi_sector assignment out of btrfs_add_compressed_bio_pages

Adding pages to a bio has nothing to do with the sector. Move the
assignment to the two callers in preparation for cleanin

btrfs: move the bi_sector assignment out of btrfs_add_compressed_bio_pages

Adding pages to a bio has nothing to do with the sector. Move the
assignment to the two callers in preparation for cleaning up
btrfs_add_compressed_bio_pages.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: store a pointer to the original btrfs_bio in struct compressed_bio

The original bio must be a btrfs_bio, so store a pointer to the
btrfs_bio for better type checking.

Reviewed-by: Anand Jain

btrfs: store a pointer to the original btrfs_bio in struct compressed_bio

The original bio must be a btrfs_bio, so store a pointer to the
btrfs_bio for better type checking.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: pass a btrfs_bio to btrfs_submit_compressed_read

btrfs_submit_compressed_read expects the bio passed to it to be embedded
into a btrfs_bio structure. Pass the btrfs_bio directly to increase

btrfs: pass a btrfs_bio to btrfs_submit_compressed_read

btrfs_submit_compressed_read expects the bio passed to it to be embedded
into a btrfs_bio structure. Pass the btrfs_bio directly to increase type
safety and make the code self-documenting.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: pass a btrfs_bio to btrfs_submit_bio

btrfs_submit_bio expects the bio passed to it to be embedded into a
btrfs_bio structure. Pass the btrfs_bio directly to increase type
safety and make the

btrfs: pass a btrfs_bio to btrfs_submit_bio

btrfs_submit_bio expects the bio passed to it to be embedded into a
btrfs_bio structure. Pass the btrfs_bio directly to increase type
safety and make the code self-documenting.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: move zero filling of compressed read bios into common code

All algorithms have to fill the remainder of the orig_bio with zeroes,
so do it in common code.

Reviewed-by: Anand Jain <anand.jain

btrfs: move zero filling of compressed read bios into common code

All algorithms have to fill the remainder of the orig_bio with zeroes,
so do it in common code.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: fold finish_compressed_bio_write into btrfs_finish_compressed_write_work

Fold finish_compressed_bio_write into its only caller as there is no
reason to keep them separate.

Reviewed-by: Johan

btrfs: fold finish_compressed_bio_write into btrfs_finish_compressed_write_work

Fold finish_compressed_bio_write into its only caller as there is no
reason to keep them separate.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: don't clear page->mapping in btrfs_free_compressed_pages

No one ever set ->mapping on these pages, so don't bother clearing it.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
S

btrfs: don't clear page->mapping in btrfs_free_compressed_pages

No one ever set ->mapping on these pages, so don't bother clearing it.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: factor out a btrfs_free_compressed_pages helper

Share the code to free the compressed pages and the array to hold them
into a common helper.

Reviewed-by: Johannes Thumshirn <johannes.thumshi

btrfs: factor out a btrfs_free_compressed_pages helper

Share the code to free the compressed pages and the array to hold them
into a common helper.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: factor out a btrfs_add_compressed_bio_pages helper

Factor out a common helper to add the compressed_bio pages to the
bio that is shared by the compressed read and write path.

Reviewed-by: Jo

btrfs: factor out a btrfs_add_compressed_bio_pages helper

Factor out a common helper to add the compressed_bio pages to the
bio that is shared by the compressed read and write path.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: use the bbio file offset in add_ra_bio_pages

struct btrfs_bio now has a file_offset field set up by all submitters.
Use that value combined with the bio size in add_ra_bio_pages to
calculate

btrfs: use the bbio file offset in add_ra_bio_pages

struct btrfs_bio now has a file_offset field set up by all submitters.
Use that value combined with the bio size in add_ra_bio_pages to
calculate the last offset in the bio.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: use the bbio file offset in btrfs_submit_compressed_read

struct btrfs_bio now has a file_offset field set up by all submitters.
Use that in btrfs_submit_compressed_read instead of recalculati

btrfs: use the bbio file offset in btrfs_submit_compressed_read

struct btrfs_bio now has a file_offset field set up by all submitters.
Use that in btrfs_submit_compressed_read instead of recalculating the
value.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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btrfs: remove redundant free_extent_map in btrfs_submit_compressed_read

em can't be non-NULL after the free_extent_map label. Also remove
the now pointless clearing of em to NULL after freeing it.

btrfs: remove redundant free_extent_map in btrfs_submit_compressed_read

em can't be non-NULL after the free_extent_map label. Also remove
the now pointless clearing of em to NULL after freeing it.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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