btrfs: migrate the block group ref counting stuff

Another easy set to move over to block-group.c.
Signed-off-by: NJosef Bacik <josef@toxicpanda.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

fs/btrfs/block-group.c

@@ -3,6 +3,31 @@
 #include "ctree.h"
 #include "block-group.h"
 
+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)) {
+		WARN_ON(cache->pinned > 0);
+		WARN_ON(cache->reserved > 0);
+
+		/*
+		 * If not empty, someone is still holding mutex of
+		 * full_stripe_lock, which can only be released by caller.
+		 * And it will definitely cause use-after-free when caller
+		 * tries to release full stripe lock.
+		 *
+		 * No better way to resolve, but only to warn.
+		 */
+		WARN_ON(!RB_EMPTY_ROOT(&cache->full_stripe_locks_root.root));
+		kfree(cache->free_space_ctl);
+		kfree(cache);
+	}
+}
+
 /*
  * This will return the block group at or after bytenr if contains is 0, else
  * it will return the block group that contains the bytenr

fs/btrfs/block-group.h

@@ -157,5 +157,7 @@ struct btrfs_block_group_cache *btrfs_lookup_block_group(
 		struct btrfs_fs_info *info, u64 bytenr);
 struct btrfs_block_group_cache *btrfs_next_block_group(
 		struct btrfs_block_group_cache *cache);
+void btrfs_get_block_group(struct btrfs_block_group_cache *cache);
+void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
 
 #endif /* BTRFS_BLOCK_GROUP_H */

fs/btrfs/ctree.h

@@ -2479,7 +2479,6 @@ void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg);
 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
 void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg);
-void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
 			   unsigned long count);
 void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
@@ -2496,8 +2495,6 @@ int btrfs_pin_extent_for_log_replay(struct btrfs_fs_info *fs_info,
 int btrfs_exclude_logged_extents(struct extent_buffer *eb);
 int btrfs_cross_ref_exist(struct btrfs_root *root,
 			  u64 objectid, u64 offset, u64 bytenr);
-void btrfs_get_block_group(struct btrfs_block_group_cache *cache);
-void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
 struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
 					     struct btrfs_root *root,
 					     u64 parent, u64 root_objectid,

fs/btrfs/extent-tree.c

@@ -68,31 +68,6 @@ 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)) {
-		WARN_ON(cache->pinned > 0);
-		WARN_ON(cache->reserved > 0);
-
-		/*
-		 * If not empty, someone is still holding mutex of
-		 * full_stripe_lock, which can only be released by caller.
-		 * And it will definitely cause use-after-free when caller
-		 * tries to release full stripe lock.
-		 *
-		 * No better way to resolve, but only to warn.
-		 */
-		WARN_ON(!RB_EMPTY_ROOT(&cache->full_stripe_locks_root.root));
-		kfree(cache->free_space_ctl);
-		kfree(cache);
-	}
-}
-
 /*
  * this adds the block group to the fs_info rb tree for the block group
  * cache