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>

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index cb0137e4047f2972bf2a7c3a277f01b51b311fe3..2974c4744d5cbb8f38046711fb6f5122b8139bd5 100644 (file)
--- 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;
 }