All of its children take btrfs_inode so bubble up this requirement to
btrfs_delalloc_reserve_space's interface and stop calling BTRFS_I
internally.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Instead of calling BTRFS_I on the passed vfs_inode take btrfs_inode
directly.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It needs btrfs_inode so take it as a parameter directly.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It only uses btrfs_inode internally so take it as a parameter.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

No point in taking an inode only to get btrfs_fs_info from it, instead
take btrfs_fs_info directly.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Preparation to make btrfs_dirty_pages take btrfs_inode as parameter.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

This function really needs a btrfs_inode and not a generic vfs one. Take
it as a parameter and get rid of superfluous BTRFS_I() calls.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Take btrfs_inode directly and stop using superfulous BTRFS_I calls.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Simply forwards its argument so let's get rid of one extra BTRFS_I by
taking btrfs_inode directly.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

All children now take btrfs_inode so convert it to taking it as a
parameter as well.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Gets rid of superfulous BTRFS_I() calls and prepare for converting
btrfs_run_delalloc_range to using btrfs_inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Simply gets rid of superfluous BTRFS_I() calls.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Gets rid of superfluous BTRFS_I() calls.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Preparation to converting btrfs_run_delalloc_range to using btrfs_inode
without BTRFS_I() calls.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It really wants btrfs_inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It doesn't really need vfs_inode but btrfs_inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It only uses vfs inode for assigning it to the async_chunk function.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It only really uses btrfs_inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It really wants btrfs_inode and is prepration to converting
run_delalloc_nocow to taking btrfs_inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>c
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It just forwards its argument to __btrfs_qgroup_release_data.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

All but 3 uses require vfs_inode so convert the logic to have
btrfs_inode be the main inode struct.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Majority of its uses are for btrfs_inode so take it as an argument
directly.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It simpy forwards its inode argument to __btrfs_add_ordered_extent which
already takes btrfs_inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

All its children functions take btrfs_inode so convert it to taking
btrfs_inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Preparation to converting its callers to taking btrfs_inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It passes btrfs_inode to its callee so change the interface.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NAnand Jain <anand.jain@oracle.com>
Signed-off-by: NQu Wenruo <wqu@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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

[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: NMartin Doucha <martin.doucha@suse.com>
Reviewed-by: NFilipe Manana <fdmanana@suse.com>
Reviewed-by: NAnand Jain <anand.jain@oracle.com>
Signed-off-by: NQu Wenruo <wqu@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

The fiemap callback is not part of UAPI interface and the prototypes
don't have the __u64 types either.
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Will enable converting btrfs_submit_compressed_write to btrfs_inode more
easily.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It really wants btrfs_inode and not a vfs inode.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It doesn't use the generic vfs inode for anything use btrfs_inode
directly.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

[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: f695fdce ("btrfs: qgroup: Introduce functions to release/free qgroup reserve data space")
Suggested-by: NJosef Bacik <josef@toxicpanda.com>
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NQu Wenruo <wqu@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>