Commit Graph

935094 Commits

Author SHA1 Message Date
Nikolay Borisov
c7ee1819dc btrfs: make btrfs_submit_compressed_write take btrfs_inode
Majority of its uses are for btrfs_inode so take it as an argument
directly.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:31 +02:00
Nikolay Borisov
4cc612090b btrfs: make btrfs_add_ordered_extent_compress take btrfs_inode
It simpy forwards its inode argument to __btrfs_add_ordered_extent which
already takes btrfs_inode.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:31 +02:00
Nikolay Borisov
6e26c44223 btrfs: make cow_file_range take btrfs_inode
All its children functions take btrfs_inode so convert it to taking
btrfs_inode.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:31 +02:00
Nikolay Borisov
e7fbf60453 btrfs: make btrfs_add_ordered_extent take btrfs_inode
Preparation to converting its callers to taking btrfs_inode.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:31 +02:00
Nikolay Borisov
a0349401c1 btrfs: make cow_file_range_inline take btrfs_inode
It has only 2 uses for the vfs_inode - insert_inline_extent and
i_size_read.  On the flipside it will allow converting its callers to
btrfs_inode, so convert it to taking btrfs_inode.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:30 +02:00
Nikolay Borisov
8b8a979f1f btrfs: make btrfs_qgroup_free_data take btrfs_inode
It passes btrfs_inode to its callee so change the interface.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:30 +02:00
Nikolay Borisov
8769af96cf btrfs: make __btrfs_qgroup_release_data take btrfs_inode
It uses vfs_inode only for a tracepoint so convert its interface to take
btrfs_inode directly.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:30 +02:00
Nikolay Borisov
df2cfd131f btrfs: make qgroup_free_reserved_data take btrfs_inode
It only uses btrfs_inode so can just as easily take it as an argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:30 +02:00
Nikolay Borisov
f0cdd15c21 btrfs: tracepoints: convert flush states to using EM macros
Only 6 out of all flush states were being printed correctly since
only they were exported via the TRACE_DEFINE_ENUM macro. This patch
converts all flush states to use the newly introduced EM macro so that
they can all be printed correctly.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:30 +02:00
Nikolay Borisov
c92bb3046f btrfs: tracepoints: switch extent_io_tree_owner to using EM macro
This fixes correct pint out of the extent io tree owner in
btrfs_set_extent_bit/btrfs_clear_extent_bit/btrfs_convert_extent_bit
tracepoints.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:30 +02:00
Nikolay Borisov
1cb1f0b248 btrfs: tracepoints: fix qgroup reservation type printing
Since qgroup's reservation types are define in a macro they must be
exported to user space in order for user space tools to convert raw
binary data to symbolic names. Currently trace-cmd report produces
the following output:

kworker/u8:2-459   [003]  1208.543587: qgroup_update_reserve:
2b742cae-e0e5-4def-9ef7-28a9b34a951e: qgid=5 type=0x2 cur_reserved=54870016 diff=-32768

With this fix the output is:

kworker/u8:2-459   [003]  1208.543587: qgroup_update_reserve:
2b742cae-e0e5-4def-9ef7-28a9b34a951e: qgid=5 type=BTRFS_QGROUP_RSV_META_PREALLOC cur_reserved=54870016 diff=-32768

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:29 +02:00
Nikolay Borisov
5bca2c952c btrfs: tracepoints: move FLUSH_ACTIONS define
Since all enums used in btrfs' tracepoints are going to be redefined
to allow proper parsing of their values by userspace tools let's
rearrange when they are defined. This will allow to use only a single
set of #define EM/#undef EM sequence. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:29 +02:00
Nikolay Borisov
0840dd28b5 btrfs: tracepoints: fix extent type symbolic name print
extent's type is an enum and this requires that the enum values be
exported to user space so that user space tools can correctly map raw
binary data to the symbolic name. Currently tracepoints using
btrfs__file_extent_item_regular or btrfs__file_extent_item_inline result
in the following output:

fio-443   [002]   586.609450: btrfs_get_extent_show_fi_regular: f0c3bf8e-0174-4bcc-92aa-6c2d62430420:i
	root=5(FS_TREE) inode=258 size=2136457216 disk_isize=0
	file extent range=[2126946304 2136457216] (num_bytes=9510912
	ram_bytes=9510912 disk_bytenr=0 disk_num_bytes=0 extent_offset=0
	type=0x1 compression=0

E.g type is 0x1 . With this patch applie the output is:

<ommitted for brevity>  disk_bytenr=141348864 disk_num_bytes=4096 extent_offset=0 type=REG compression=0

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:29 +02:00
Nikolay Borisov
45e31869cc btrfs: tracepoints: fix btrfs_trigger_flush symbolic string for flags
When tracepoints use __print_symbolic to print textual representation of
a value that comes from an ENUM each enum value needs to be exported
to user space so that user space tools can convert the binary value
data to the trings as user space does not know what those enums are
about.

Doing a trace-cmd record && trace-cmd report currently results in:

kworker/u8:1-61    [000]    66.299527:
	btrfs_flush_space:    5302ee13-c65e-45bb-98ef-8fe3835bd943:
	state=3(0x3) flags=4(METADATA) num_bytes=2621440 ret=0

I.e state is not translated to its symbolic counterpart. With this patch
applied the output is:

fio-370   [002]    56.762402: btrfs_trigger_flush:  d04cd7ac-38e2-452f-a7f5-8157529fd5f0:
	preempt: flush=3(BTRFS_RESERVE_FLUSH_ALL) flags=4(METADATA) bytes=655360

See also 190f0b76ca ("mm: tracing: Export enums in tracepoints to user
space").

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:29 +02:00
David Sterba
3502a8c0dc btrfs: allow use of global block reserve for balance item deletion
On a filesystem with exhausted metadata, but still enough to start
balance, it's possible to hit this error:

[324402.053842] BTRFS info (device loop0): 1 enospc errors during balance
[324402.060769] BTRFS info (device loop0): balance: ended with status: -28
[324402.172295] BTRFS: error (device loop0) in reset_balance_state:3321: errno=-28 No space left

It fails inside reset_balance_state and turns the filesystem to
read-only, which is unnecessary and should be fixed too, but the problem
is caused by lack for space when the balance item is deleted. This is a
one-time operation and from the same rank as unlink that is allowed to
use the global block reserve. So do the same for the balance item.

Status of the filesystem (100GiB) just after the balance fails:

$ btrfs fi df mnt
Data, single: total=80.01GiB, used=38.58GiB
System, single: total=4.00MiB, used=16.00KiB
Metadata, single: total=19.99GiB, used=19.48GiB
GlobalReserve, single: total=512.00MiB, used=50.11MiB

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:29 +02:00
Qu Wenruo
38d37aa9c3 btrfs: refactor btrfs_check_can_nocow() into two variants
The function btrfs_check_can_nocow() now has two completely different
call patterns.

For nowait variant, callers don't need to do any cleanup.  While for
wait variant, callers need to release the lock if they can do nocow
write.

This is somehow confusing, and is already a problem for the exported
btrfs_check_can_nocow().

So this patch will separate the different patterns into different
functions.
For nowait variant, the function will be called check_nocow_nolock().
For wait variant, the function pair will be btrfs_check_nocow_lock()
btrfs_check_nocow_unlock().

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:28 +02:00
Qu Wenruo
e4ecaf90bc btrfs: add comments for btrfs_check_can_nocow() and can_nocow_extent()
These two functions have extra conditions that their callers need to
meet, and some not-that-common parameters used for return value.

So adding some comments may save reviewers some time.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:28 +02:00
Qu Wenruo
6d4572a9d7 btrfs: allow btrfs_truncate_block() to fallback to nocow for data space reservation
[BUG]
When the data space is exhausted, even if the inode has NOCOW attribute,
we will still refuse to truncate unaligned range due to ENOSPC.

The following script can reproduce it pretty easily:
  #!/bin/bash

  dev=/dev/test/test
  mnt=/mnt/btrfs

  umount $dev &> /dev/null
  umount $mnt &> /dev/null

  mkfs.btrfs -f $dev -b 1G
  mount -o nospace_cache $dev $mnt
  touch $mnt/foobar
  chattr +C $mnt/foobar

  xfs_io -f -c "pwrite -b 4k 0 4k" $mnt/foobar > /dev/null
  xfs_io -f -c "pwrite -b 4k 0 1G" $mnt/padding &> /dev/null
  sync

  xfs_io -c "fpunch 0 2k" $mnt/foobar
  umount $mnt

Currently this will fail at the fpunch part.

[CAUSE]
Because btrfs_truncate_block() always reserves space without checking
the NOCOW attribute.

Since the writeback path follows NOCOW bit, we only need to bother the
space reservation code in btrfs_truncate_block().

[FIX]
Make btrfs_truncate_block() follow btrfs_buffered_write() to try to
reserve data space first, and fall back to NOCOW check only when we
don't have enough space.

Such always-try-reserve is an optimization introduced in
btrfs_buffered_write(), to avoid expensive btrfs_check_can_nocow() call.

This patch will export check_can_nocow() as btrfs_check_can_nocow(), and
use it in btrfs_truncate_block() to fix the problem.

Reported-by: Martin Doucha <martin.doucha@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:28 +02:00
David Sterba
b547a88ea5 btrfs: start deprecation of mount option inode_cache
Estimated time of removal of the functionality is 5.11, the option will
be still parsed but will have no effect.

Reasons for deprecation and removal:

- very poor naming choice of the mount option, it's supposed to cache
  and reuse the inode _numbers_, but it sounds a some generic cache for
  inodes

- the only known usecase where this option would make sense is on a
  32bit architecture where inode numbers in one subvolume would be
  exhausted due to 32bit inode::i_ino

- the cache is stored on disk, consumes space, needs to be loaded and
  written back

- new inode number allocation is slower due to lookups into the cache
  (compared to a simple increment which is the default)

- uses the free-space-cache code that is going to be deprecated as well
  in the future

Known problems:

- since 2011, returning EEXIST when there's not enough space in a page
  to store all checksums, see commit 4b9465cb9e ("Btrfs: add mount -o
  inode_cache")

Remaining issues:

- if the option was enabled, new inodes created, the option disabled
  again, the cache is still stored on the devices and there's currently
  no way to remove it

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:28 +02:00
David Sterba
a2570ef330 btrfs: remove unused btrfs_root::defrag_trans_start
Last touched in 2013 by commit de78b51a28 ("btrfs: remove cache only
arguments from defrag path") that was the only code that used the value.
Now it's only set but never used for anything, so we can remove it.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:28 +02:00
David Sterba
bab16e21e8 btrfs: don't use UAPI types for fiemap callback
The fiemap callback is not part of UAPI interface and the prototypes
don't have the __u64 types either.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:27 +02:00
Denis Efremov
5af9d6ef3f btrfs: tests: remove if duplicate in __check_free_space_extents()
num_extents is already checked in the next if condition and can
be safely removed.

Signed-off-by: Denis Efremov <efremov@linux.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:27 +02:00
Johannes Thumshirn
923eb52365 btrfs: use free_root_extent_buffer to free root
In btrfs_put_root() we're freeing a btrfs_root's 'node' and 'commit_root'
extent buffers manually via kfree(), while we're using
free_root_extent_buffers() in the free_root_pointers() function above.

free_root_extent_buffers() also NULLs the pointers after freeing, which
mitigates potential double frees.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:27 +02:00
Nikolay Borisov
4e9d0d0109 btrfs: use for loop in prealloc_file_extent_cluster
This function iterates all extents in the extent cluster, make this
intention obvious by using a for loop. No functional chanes.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:27 +02:00
Nikolay Borisov
214e61d07e btrfs: perform data management operations outside of inode lock
btrfs_alloc_data_chunk_ondemand and btrfs_free_reserved_data_space_noquota
don't really use the guts of the inodes being passed to them. This
implies it's not required to call them under extent lock. Move code
around in prealloc_file_extent_cluster to do the heavy, data alloc/free
operations outside of the lock. This also makes the 'out' label
unnecessary, so remove it.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:27 +02:00
Nikolay Borisov
c171edd5c8 btrfs: remove hole check in prealloc_file_extent_cluster
Extents in the extent cluster are guaranteed to be contiguous as such
the hole check inside the loop can never trigger. In fact this check was
never functional since it was added in 18513091af ("btrfs: update
btrfs_space_info's bytes_may_use timely") which came after the commit
introducing clustered/contiguous extents 0257bb82d2 ("Btrfs: relocate
file extents in clusters").

Let's just remove it as it adds noise to the source.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:27 +02:00
Nikolay Borisov
906c448c3d btrfs: make __btrfs_drop_extents take btrfs_inode
It has only 4 uses of a vfs_inode for inode_sub_bytes but unifies the
interface with the non  __ prefixed version. Will also makes converting
its callers to btrfs_inode easier.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:26 +02:00
Nikolay Borisov
bd242a08a6 btrfs: make btrfs_csum_one_bio takae btrfs_inode
Will enable converting btrfs_submit_compressed_write to btrfs_inode more
easily.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:26 +02:00
Nikolay Borisov
ad7ff17b65 btrfs: make extent_clear_unlock_delalloc take btrfs_inode
It has one VFS and 1 btrfs inode usages but converting it to btrfs_inode
interface will allow seamless conversion of its callers.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:26 +02:00
Nikolay Borisov
4b67c11dd1 btrfs: make create_io_em take btrfs_inode
It really wants a btrfs_inode and will allow submit_compressed_extents
to be completely converted to btrfs_inode in follow up patches.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:26 +02:00
Nikolay Borisov
7bfa953501 btrfs: make btrfs_reloc_clone_csums take btrfs_inode
It really wants btrfs_inode and not a vfs inode.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:26 +02:00
Nikolay Borisov
c350437269 btrfs: make btrfs_lookup_ordered_extent take btrfs_inode
It doesn't use the generic vfs inode for anything use btrfs_inode
directly.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:25 +02:00
Nikolay Borisov
43c69849ae btrfs: make get_extent_allocation_hint take btrfs_inode
It doesn't use the vfs inode for anything, can just as easily take
btrfs_inode.  Follow up patches will convert callers as well.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:25 +02:00
Nikolay Borisov
da69fea9f7 btrfs: make __btrfs_add_ordered_extent take struct btrfs_inode
This is internal btrfs function what really needs the vfs_inode only for
igrab and a tracepoint.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:25 +02:00
Filipe Manana
3ef64143a7 btrfs: remove no longer used trans_list member of struct btrfs_ordered_extent
The 'trans_list' member of an ordered extent was used to keep track of the
ordered extents for which a transaction commit had to wait. These were
ordered extents that were started and logged by an fsync. However we don't
do that anymore and before we stopped doing it we changed the approach to
wait for the ordered extents in commit 161c3549b4 ("Btrfs: change how
we wait for pending ordered extents"), which stopped using that list and
therefore the 'trans_list' member is not used anymore since that commit.
So just remove it since it's doing nothing and making each ordered extent
structure waste memory (2 pointers).

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:25 +02:00
Filipe Manana
cd8d39f4ae btrfs: remove no longer used log_list member of struct btrfs_ordered_extent
The 'log_list' member of an ordered extent was used keep track of which
ordered extents we needed to wait after logging metadata, but is not used
anymore since commit 5636cf7d6d ("btrfs: remove the logged extents
infrastructure"), as we now always wait on ordered extent completion
before logging metadata. So just remove it since it's doing nothing and
making each ordered extent structure waste more memory (2 pointers).

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:25 +02:00
David Sterba
ce6ef5abe6 btrfs: add little-endian optimized key helpers
The CPU and on-disk keys are mapped to two different structures because
of the endianness. There's an intermediate buffer used to do the
conversion, but this is not necessary when CPU and on-disk endianness
match.

Add optimized versions of helpers that take disk_key and use the buffer
directly for CPU keys or drop the intermediate buffer and conversion.

This saves a lot of stack space accross many functions and removes about
6K of generated binary code:

   text    data     bss     dec     hex filename
1090439   17468   14912 1122819  112203 pre/btrfs.ko
1084613   17456   14912 1116981  110b35 post/btrfs.ko

Delta: -5826

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:24 +02:00
Qu Wenruo
5958253cf6 btrfs: qgroup: catch reserved space leaks at unmount time
Before this patch, qgroup completely relies on per-inode extent io tree
to detect reserved data space leak.

However previous bug has already shown how release page before
btrfs_finish_ordered_io() could lead to leak, and since it's
QGROUP_RESERVED bit cleared without triggering qgroup rsv, it can't be
detected by per-inode extent io tree.

So this patch adds another (and hopefully the final) safety net to catch
qgroup data reserved space leak.  At least the new safety net catches
all the leaks during development, so it should be pretty useful in the
real world.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:24 +02:00
Qu Wenruo
7dbeaad0af btrfs: change timing for qgroup reserved space for ordered extents to fix reserved space leak
[BUG]
The following simple workload from fsstress can lead to qgroup reserved
data space leak:
  0/0: creat f0 x:0 0 0
  0/0: creat add id=0,parent=-1
  0/1: write f0[259 1 0 0 0 0] [600030,27288] 0
  0/4: dwrite - xfsctl(XFS_IOC_DIOINFO) f0[259 1 0 0 64 627318] return 25, fallback to stat()
  0/4: dwrite f0[259 1 0 0 64 627318] [610304,106496] 0

This would cause btrfs qgroup to leak 20480 bytes for data reserved
space.  If btrfs qgroup limit is enabled, such leak can lead to
unexpected early EDQUOT and unusable space.

[CAUSE]
When doing direct IO, kernel will try to writeback existing buffered
page cache, then invalidate them:
  generic_file_direct_write()
  |- filemap_write_and_wait_range();
  |- invalidate_inode_pages2_range();

However for btrfs, the bi_end_io hook doesn't finish all its heavy work
right after bio ends.  In fact, it delays its work further:

  submit_extent_page(end_io_func=end_bio_extent_writepage);
  end_bio_extent_writepage()
  |- btrfs_writepage_endio_finish_ordered()
     |- btrfs_init_work(finish_ordered_fn);

  <<< Work queue execution >>>
  finish_ordered_fn()
  |- btrfs_finish_ordered_io();
     |- Clear qgroup bits

This means, when filemap_write_and_wait_range() returns,
btrfs_finish_ordered_io() is not guaranteed to be executed, thus the
qgroup bits for related range are not cleared.

Now into how the leak happens, this will only focus on the overlapping
part of buffered and direct IO part.

1. After buffered write
   The inode had the following range with QGROUP_RESERVED bit:
   	596		616K
	|///////////////|
   Qgroup reserved data space: 20K

2. Writeback part for range [596K, 616K)
   Write back finished, but btrfs_finish_ordered_io() not get called
   yet.
   So we still have:
   	596K		616K
	|///////////////|
   Qgroup reserved data space: 20K

3. Pages for range [596K, 616K) get released
   This will clear all qgroup bits, but don't update the reserved data
   space.
   So we have:
   	596K		616K
	|		|
   Qgroup reserved data space: 20K
   That number doesn't match the qgroup bit range anymore.

4. Dio prepare space for range [596K, 700K)
   Qgroup reserved data space for that range, we got:
   	596K		616K			700K
	|///////////////|///////////////////////|
   Qgroup reserved data space: 20K + 104K = 124K

5. btrfs_finish_ordered_range() gets executed for range [596K, 616K)
   Qgroup free reserved space for that range, we got:
   	596K		616K			700K
	|		|///////////////////////|
   We need to free that range of reserved space.
   Qgroup reserved data space: 124K - 20K = 104K

6. btrfs_finish_ordered_range() gets executed for range [596K, 700K)
   However qgroup bit for range [596K, 616K) is already cleared in
   previous step, so we only free 84K for qgroup reserved space.
   	596K		616K			700K
	|		|			|
   We need to free that range of reserved space.
   Qgroup reserved data space: 104K - 84K = 20K

   Now there is no way to release that 20K unless disabling qgroup or
   unmounting the fs.

[FIX]
This patch will change the timing of btrfs_qgroup_release/free_data()
call.  Here it uses buffered COW write as an example.

	The new timing			|	The old timing
----------------------------------------+---------------------------------------
 btrfs_buffered_write()			| btrfs_buffered_write()
 |- btrfs_qgroup_reserve_data() 	| |- btrfs_qgroup_reserve_data()
					|
 btrfs_run_delalloc_range()		| btrfs_run_delalloc_range()
 |- btrfs_add_ordered_extent()  	|
    |- btrfs_qgroup_release_data()	|
       The reserved is passed into	|
       btrfs_ordered_extent structure	|
					|
 btrfs_finish_ordered_io()		| btrfs_finish_ordered_io()
 |- The reserved space is passed to 	| |- btrfs_qgroup_release_data()
    btrfs_qgroup_record			|    The resereved space is passed
					|    to btrfs_qgroup_recrod
					|
 btrfs_qgroup_account_extents()		| btrfs_qgroup_account_extents()
 |- btrfs_qgroup_free_refroot()		| |- btrfs_qgroup_free_refroot()

The point of such change is to ensure, when ordered extents are
submitted, the qgroup reserved space is already released, to keep the
timing aligned with file_write_and_wait_range().

So that qgroup data reserved space is all bound to btrfs_ordered_extent
and solve the timing mismatch.

Fixes: f695fdcef8 ("btrfs: qgroup: Introduce functions to release/free qgroup reserve data space")
Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:24 +02:00
Qu Wenruo
a7f8b1c2ac btrfs: file: reserve qgroup space after the hole punch range is locked
The incoming qgroup reserved space timing will move the data reservation
to ordered extent completely.

However in btrfs_punch_hole_lock_range() will call
btrfs_invalidate_page(), which will clear QGROUP_RESERVED bit for the
range.

In current stage it's OK, but if we're making ordered extents handle the
reserved space, then btrfs_punch_hole_lock_range() can clear the
QGROUP_RESERVED bit before we submit ordered extent, leading to qgroup
reserved space leakage.

So here change the timing to make reserve data space after
btrfs_punch_hole_lock_range().
The new timing is fine for either current code or the new code.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:24 +02:00
Qu Wenruo
9729f10a60 btrfs: inode: move qgroup reserved space release to the callers of insert_reserved_file_extent()
This is to prepare for the incoming timing change of qgroup reserved
data space and ordered extent.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:24 +02:00
Qu Wenruo
203f44c519 btrfs: inode: refactor the parameters of insert_reserved_file_extent()
Function insert_reserved_file_extent() takes a long list of parameters,
which are all for btrfs_file_extent_item, even including two reserved
members, encryption and other_encoding.

This makes the parameter list unnecessary long for a function which only
gets called twice.

This patch will refactor the parameter list, by using
btrfs_file_extent_item as parameter directly to hugely reduce the number
of parameters.

Also, since there are only two callers, one in btrfs_finish_ordered_io()
which inserts file extent for ordered extent, and one
__btrfs_prealloc_file_range().

These two call sites have completely different context, where ordered
extent can be compressed, but will always be regular extent, while the
preallocated one is never going to be compressed and always has PREALLOC
type.

So use two small wrapper for these two different call sites to improve
readability.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:23 +02:00
David Sterba
100aa5d9f9 btrfs: scrub: clean up temporary page variables in scrub_checksum_tree_block
Add proper variable for the scrub page and use it instead of repeatedly
dereferencing the other structures.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:23 +02:00
David Sterba
521e102227 btrfs: scrub: simplify tree block checksum calculation
Use a simpler iteration over tree block pages, same what csum_tree_block
does: first page always exists, loop over the rest.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:23 +02:00
David Sterba
d41ebef200 btrfs: scrub: clean up temporary page variables in scrub_checksum_data
Add proper variable for the scrub page and use it instead of repeatedly
dereferencing the other structures.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:23 +02:00
David Sterba
771aba0d12 btrfs: scrub: simplify data block checksum calculation
We have sectorsize same as PAGE_SIZE, the checksum can be calculated in
one go.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:23 +02:00
David Sterba
c746054109 btrfs: scrub: clean up temporary page variables in scrub_checksum_super
Add proper variable for the scrub page and use it instead of repeatedly
dereferencing the other structures.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:23 +02:00
David Sterba
74710cf1fb btrfs: scrub: remove temporary csum array in scrub_checksum_super
The page contents with the checksum is available during the entire
function so we don't need to make a copy.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:22 +02:00
David Sterba
83cf6d5eae btrfs: scrub: simplify superblock checksum calculation
BTRFS_SUPER_INFO_SIZE is 4096, and fits to a page on all supported
architectures, so we can calculate the checksum in one go.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:22 +02:00
David Sterba
b04852520e btrfs: scrub: unify naming of page address variables
As the page mapping has been removed, rename the variables to 'kaddr'
that we use everywhere else. The type is changed to 'char *' so pointer
arithmetic works without casts.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:22 +02:00