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>

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 52422e2..b15858e 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -3174,14 +3174,14 @@ reserve_space:
                if (ret < 0)
                        goto out;
                space_reserved = true;
-               ret = btrfs_qgroup_reserve_data(inode, &data_reserved,
-                                               alloc_start, bytes_to_reserve);
-               if (ret)
-                       goto out;
                ret = btrfs_punch_hole_lock_range(inode, lockstart, lockend,
                                                  &cached_state);
                if (ret)
                        goto out;
+               ret = btrfs_qgroup_reserve_data(inode, &data_reserved,
+                                               alloc_start, bytes_to_reserve);
+               if (ret)
+                       goto out;
                ret = btrfs_prealloc_file_range(inode, mode, alloc_start,
                                                alloc_end - alloc_start,
                                                i_blocksize(inode),