[PATCH 4.5 111/128] btrfs: fix mixed block count of available space

Greg Kroah-Hartman
2016-06-06T14:39:47Z

From: Luis de Bethencourt <luisbg@osg.samsung.com>

commit ae02d1bd070767e109f4a6f1bb1f466e9698a355 upstream.

Metadata for mixed block is already accounted in total data and should not
be counted as part of the free metadata space.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=114281
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/btrfs/super.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)

--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -2024,6 +2024,7 @@ static int btrfs_statfs(struct dentry *d
struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
int ret;
u64 thresh = 0;
+ int mixed = 0;

/*
* holding chunk_muext to avoid allocating new chunks, holding
@@ -2049,8 +2050,17 @@ static int btrfs_statfs(struct dentry *d
}
}
}
- if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
- total_free_meta += found->disk_total - found->disk_used;
+
+ /*
+ * Metadata in mixed block goup profiles are accounted in data
+ */
+ if (!mixed && found->flags & BTRFS_BLOCK_GROUP_METADATA) {
+ if (found->flags & BTRFS_BLOCK_GROUP_DATA)
+ mixed = 1;
+ else
+ total_free_meta += found->disk_total -
+ found->disk_used;
+ }

total_used += found->disk_used;
}
@@ -2088,7 +2098,7 @@ static int btrfs_statfs(struct dentry *d
*/
thresh = 4 * 1024 * 1024;

- if (total_free_meta - thresh < block_rsv->size)
+ if (!mixed && total_free_meta - thresh < block_rsv->size)
buf->f_bavail = 0;

buf->f_type = BTRFS_SUPER_MAGIC;