X-Git-Url: http://git.osdn.net/view?a=blobdiff_plain;f=fs%2Fbtrfs%2Fblock-group.h;h=b6ee70a039c70ca01f99479ff193cf3704243a07;hb=d479c5a1919b4e569dcd3ae9c84ed74a675d0b94;hp=107bb557ca8de8ea08d2e0d62613105ae0b95b04;hpb=fdfa3a6778b194974df77b384cc71eb2e503639a;p=tomoyo%2Ftomoyo-test1.git

diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index 107bb557ca8d..b6ee70a039c7 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -129,8 +129,17 @@ struct btrfs_block_group {
 	/* For read-only block groups */
 	struct list_head ro_list;
 
+	/*
+	 * When non-zero it means the block group's logical address and its
+	 * device extents can not be reused for future block group allocations
+	 * until the counter goes down to 0. This is to prevent them from being
+	 * reused while some task is still using the block group after it was
+	 * deleted - we want to make sure they can only be reused for new block
+	 * groups after that task is done with the deleted block group.
+	 */
+	atomic_t frozen;
+
 	/* For discard operations */
-	atomic_t trimming;
 	struct list_head discard_list;
 	int discard_index;
 	u64 discard_eligible_time;
@@ -283,6 +292,9 @@ static inline int btrfs_block_group_done(struct btrfs_block_group *cache)
 		cache->cached == BTRFS_CACHE_ERROR;
 }
 
+void btrfs_freeze_block_group(struct btrfs_block_group *cache);
+void btrfs_unfreeze_block_group(struct btrfs_block_group *cache);
+
 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
 		     u64 physical, u64 **logical, int *naddrs, int *stripe_len);