Btrfs: qgroup, Account data space in more proper timings.
Currenly, in data writing, ->reserved is accounted in
fill_delalloc(), but ->may_use is released in clear_bit_hook()
which is called by btrfs_finish_ordered_io(). That's too late,
that said, between fill_delalloc() and btrfs_finish_ordered_io(),
the data is doublely accounted by qgroup. It will cause some
unexpected -EDQUOT.
Example:
# btrfs quota enable /root/btrfs-auto-test/
# btrfs subvolume create /root/btrfs-auto-test//sub
Create subvolume '/root/btrfs-auto-test/sub'
# btrfs qgroup limit 1G /root/btrfs-auto-test//sub
dd if=/dev/zero of=/root/btrfs-auto-test//sub/file bs=1024 count=1500000
dd: error writing '/root/btrfs-auto-test//sub/file': Disk quota exceeded
681353+0 records in
681352+0 records out
697704448 bytes (698 MB) copied, 8.15563 s, 85.5 MB/s
It's (698 MB) when we got an -EDQUOT, but we limit it by 1G.
This patch move the btrfs_qgroup_reserve/free() for data from
btrfs_delalloc_reserve/release_metadata() to btrfs_check_data_free_space()
and btrfs_free_reserved_data_space(). Then the accounter in qgroup
will be updated at the same time with the accounter in space_info updated.
In this way, the unexpected -EDQUOT will be killed.
Reported-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index fd105c1..faef1d6 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2549,7 +2549,6 @@
{
struct inode *inode = file_inode(file);
struct extent_state *cached_state = NULL;
- struct btrfs_root *root = BTRFS_I(inode)->root;
u64 cur_offset;
u64 last_byte;
u64 alloc_start;
@@ -2577,11 +2576,6 @@
ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start);
if (ret)
return ret;
- if (root->fs_info->quota_enabled) {
- ret = btrfs_qgroup_reserve(root, alloc_end - alloc_start);
- if (ret)
- goto out_reserve_fail;
- }
mutex_lock(&inode->i_mutex);
ret = inode_newsize_ok(inode, alloc_end);
@@ -2674,6 +2668,7 @@
} else if (actual_end > inode->i_size &&
!(mode & FALLOC_FL_KEEP_SIZE)) {
struct btrfs_trans_handle *trans;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
/*
* We didn't need to allocate any more space, but we
@@ -2710,9 +2705,6 @@
&cached_state, GFP_NOFS);
out:
mutex_unlock(&inode->i_mutex);
- if (root->fs_info->quota_enabled)
- btrfs_qgroup_free(root, alloc_end - alloc_start);
-out_reserve_fail:
/* Let go of our reservation. */
btrfs_free_reserved_data_space(inode, alloc_end - alloc_start);
return ret;