1 files changed, 23 insertions, 17 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 56e50137d0e6..559f72489b3b 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -83,6 +83,17 @@ static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
         return (cache->flags & bits) == bits;
 }
 
+void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
+{
+        atomic_inc(&cache->count);
+}
+
+void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
+{
+        if (atomic_dec_and_test(&cache->count))
+                kfree(cache);
+}
+
 /*
  * this adds the block group to the fs_info rb tree for the block group
  * cache
@@ -156,7 +167,7 @@ block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
                 }
         }
         if (ret)
-                atomic_inc(&ret->count);
+                btrfs_get_block_group(ret);
         spin_unlock(&info->block_group_cache_lock);
 
         return ret;
@@ -407,6 +418,8 @@ err:
 
         put_caching_control(caching_ctl);
         atomic_dec(&block_group->space_info->caching_threads);
+        btrfs_put_block_group(block_group);
+
         return 0;
 }
 
@@ -447,6 +460,7 @@ static int cache_block_group(struct btrfs_block_group_cache *cache)
         up_write(&fs_info->extent_commit_sem);
 
         atomic_inc(&cache->space_info->caching_threads);
+        btrfs_get_block_group(cache);
 
         tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
                           cache->key.objectid);
@@ -486,12 +500,6 @@ struct btrfs_block_group_cache *btrfs_lookup_block_group(
         return cache;
 }
 
-void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
-{
-        if (atomic_dec_and_test(&cache->count))
-                kfree(cache);
-}
-
 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
                                                   u64 flags)
 {
@@ -2582,7 +2590,7 @@ next_block_group(struct btrfs_root *root,
         if (node) {
                 cache = rb_entry(node, struct btrfs_block_group_cache,
                                  cache_node);
-                atomic_inc(&cache->count);
+                btrfs_get_block_group(cache);
         } else
                 cache = NULL;
         spin_unlock(&root->fs_info->block_group_cache_lock);
@@ -4227,7 +4235,7 @@ search:
                 u64 offset;
                 int cached;
 
-                atomic_inc(&block_group->count);
+                btrfs_get_block_group(block_group);
                 search_start = block_group->key.objectid;
 
 have_block_group:
@@ -4315,7 +4323,7 @@ have_block_group:
 
                                 btrfs_put_block_group(block_group);
                                 block_group = last_ptr->block_group;
-                                atomic_inc(&block_group->count);
+                                btrfs_get_block_group(block_group);
                                 spin_unlock(&last_ptr->lock);
                                 spin_unlock(&last_ptr->refill_lock);
 
@@ -5394,10 +5402,6 @@ static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
         int ret;
 
         while (level >= 0) {
-                if (path->slots[level] >=
-                    btrfs_header_nritems(path->nodes[level]))
-                        break;
-
                 ret = walk_down_proc(trans, root, path, wc, lookup_info);
                 if (ret > 0)
                         break;
@@ -5405,6 +5409,10 @@ static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
                 if (level == 0)
                         break;
 
+                if (path->slots[level] >=
+                    btrfs_header_nritems(path->nodes[level]))
+                        break;
+
                 ret = do_walk_down(trans, root, path, wc, &lookup_info);
                 if (ret > 0) {
                         path->slots[level]++;
@@ -7395,9 +7403,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
                         wait_block_group_cache_done(block_group);
 
                 btrfs_remove_free_space_cache(block_group);
-
-                WARN_ON(atomic_read(&block_group->count) != 1);
-                kfree(block_group);
+                btrfs_put_block_group(block_group);
 
                 spin_lock(&info->block_group_cache_lock);
         }