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| author | Qu Wenruo <quwenruo@cn.fujitsu.com> | 2017-02-27 15:10:38 +0800 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2017-06-29 20:17:02 +0200 |
| commit | 364ecf3651e0862152c8b340d7cb3021dc0122c7 (patch) | |
| tree | 9e1e9d93a88677df69305345f02efae073c042b3 /fs/btrfs/file.c | |
| parent | a12b877b557dde885bdb6978cec86bf761e63c9a (diff) | |
| download | lwn-364ecf3651e0862152c8b340d7cb3021dc0122c7.tar.gz lwn-364ecf3651e0862152c8b340d7cb3021dc0122c7.zip | |
btrfs: qgroup: Introduce extent changeset for qgroup reserve functions
Introduce a new parameter, struct extent_changeset for
btrfs_qgroup_reserved_data() and its callers.
Such extent_changeset was used in btrfs_qgroup_reserve_data() to record
which range it reserved in current reserve, so it can free it in error
paths.
The reason we need to export it to callers is, at buffered write error
path, without knowing what exactly which range we reserved in current
allocation, we can free space which is not reserved by us.
This will lead to qgroup reserved space underflow.
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/file.c')
| -rw-r--r-- | fs/btrfs/file.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 5da85b080368..1b5cce51728b 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1581,6 +1581,7 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file, struct btrfs_root *root = BTRFS_I(inode)->root; struct page **pages = NULL; struct extent_state *cached_state = NULL; + struct extent_changeset *data_reserved = NULL; u64 release_bytes = 0; u64 lockstart; u64 lockend; @@ -1628,7 +1629,9 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file, reserve_bytes = round_up(write_bytes + sector_offset, fs_info->sectorsize); - ret = btrfs_check_data_free_space(inode, pos, write_bytes); + extent_changeset_release(data_reserved); + ret = btrfs_check_data_free_space(inode, &data_reserved, pos, + write_bytes); if (ret < 0) { if ((BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW | BTRFS_INODE_PREALLOC)) && @@ -1802,6 +1805,7 @@ again: } } + extent_changeset_free(data_reserved); return num_written ? num_written : ret; } @@ -2772,6 +2776,7 @@ static long btrfs_fallocate(struct file *file, int mode, { struct inode *inode = file_inode(file); struct extent_state *cached_state = NULL; + struct extent_changeset *data_reserved = NULL; struct falloc_range *range; struct falloc_range *tmp; struct list_head reserve_list; @@ -2901,8 +2906,8 @@ static long btrfs_fallocate(struct file *file, int mode, free_extent_map(em); break; } - ret = btrfs_qgroup_reserve_data(inode, cur_offset, - last_byte - cur_offset); + ret = btrfs_qgroup_reserve_data(inode, &data_reserved, + cur_offset, last_byte - cur_offset); if (ret < 0) { free_extent_map(em); break; @@ -2974,6 +2979,7 @@ out: if (ret != 0) btrfs_free_reserved_data_space(inode, alloc_start, alloc_end - cur_offset); + extent_changeset_free(data_reserved); return ret; } |