btrfs: Update stats when allocating from a cluster

When allocating extent entry from a cluster, we should update
the free_space and free_extents fields of the block group.

Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>

1 files changed, 14 insertions, 3 deletions

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index cb0137e4047..2974c4744d5 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -1843,15 +1843,26 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
                 entry->offset += bytes;
                 entry->bytes -= bytes;
 
-                if (entry->bytes == 0) {
+                if (entry->bytes == 0)
                         rb_erase(&entry->offset_index, &cluster->root);
-                        kfree(entry);
-                }
                 break;
         }
 out:
         spin_unlock(&cluster->lock);
 
+        if (!ret)
+                return 0;
+
+        spin_lock(&block_group->tree_lock);
+
+        block_group->free_space -= bytes;
+        if (entry->bytes == 0) {
+                block_group->free_extents--;
+                kfree(entry);
+        }
+
+        spin_unlock(&block_group->tree_lock);
+
         return ret;
 }