btrfs: fix mixed block count of available space

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>

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 00b8f37..bdca79c 100644 (file)
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -2051,6 +2051,7 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
        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
@@ -2076,8 +2077,17 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
                                }
                        }
                }
-               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;
        }
@@ -2115,7 +2125,7 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
         */
        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;