Btrfs: Reorder extent back refs to differentiate btree blocks from file data (f6dbff55) · Commits · e / devices / android_kernel_teracube_mt6765

fs/btrfs/ctree.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -37,11 +37,12 @@ extern struct kmem_cache *btrfs_path_cachep;

		#define BTRFS_MAGIC "_B2RfS_M"

		#define BTRFS_MAX_LEVEL 8
		#define BTRFS_ROOT_TREE_OBJECTID 1ULL
		#define BTRFS_EXTENT_TREE_OBJECTID 2ULL
		#define BTRFS_FS_TREE_OBJECTID 3ULL
		#define BTRFS_ROOT_TREE_DIR_OBJECTID 4ULL
		#define BTRFS_FIRST_FREE_OBJECTID 5ULL
		#define BTRFS_FIRST_FREE_OBJECTID 256ULL

		/*
		* we can actually store much bigger names, but lets not confuse the rest
		@@ -107,7 +108,6 @@ struct btrfs_header {
		u8 level;
		} __attribute__ ((__packed__));

		#define BTRFS_MAX_LEVEL 8
		#define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->nodesize - \
		sizeof(struct btrfs_header)) / \
		sizeof(struct btrfs_key_ptr))

fs/btrfs/extent-tree.c

+8 −8

Original line number	Diff line number	Diff line
		@@ -520,13 +520,13 @@ static int lookup_extent_backref(struct btrfs_trans_handle *trans,
		*
		* When a tree block is created, back references are inserted:
		*
		* (root->root_key.objectid, trans->transid or zero, lowest_key_objectid, level)
		* (root->root_key.objectid, trans->transid or zero, level, lowest_key_objectid)
		*
		* When a tree block is cow'd in a reference counted root,
		* new back references are added for all the blocks it points to.
		* These are of the form (trans->transid will have increased since creation):
		*
		* (root->root_key.objectid, trans->transid, lowest_key_objectid, level)
		* (root->root_key.objectid, trans->transid, level, lowest_key_objectid)
		*
		* Because the lowest_key_objectid and the level are just hints
		* they are not used when backrefs are deleted. When a backref is deleted:
		@@ -702,7 +702,7 @@ int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
		}
		return btrfs_inc_extent_ref(trans, root, root->node->start,
		root->node->len, owner_objectid,
		generation, key_objectid, level);
		generation, level, key_objectid);
		}

		int btrfs_inc_ref(struct btrfs_trans_handle trans, struct btrfs_root root,
		@@ -750,8 +750,8 @@ int btrfs_inc_ref(struct btrfs_trans_handle trans, struct btrfs_root root,
		ret = btrfs_inc_extent_ref(trans, root, bytenr,
		btrfs_level_size(root, level - 1),
		root->root_key.objectid,
		trans->transid, key.objectid,
		level - 1);
		trans->transid,
		level - 1, key.objectid);
		if (ret) {
		faili = i;
		goto fail;
		@@ -1063,8 +1063,8 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct
		}
		err = btrfs_insert_extent_backref(trans, extent_root, path,
		start, extent_root->root_key.objectid,
		0, btrfs_disk_key_objectid(&first),
		level);
		0, level,
		btrfs_disk_key_objectid(&first));
		BUG_ON(err);
		free_extent_buffer(eb);
		}
		@@ -1640,7 +1640,7 @@ struct extent_buffer __btrfs_alloc_free_block(struct btrfs_trans_handle trans,

		ret = btrfs_alloc_extent(trans, root, blocksize,
		root_objectid, ref_generation,
		first_objectid, level, empty_size, hint,
		level, first_objectid, empty_size, hint,
		(u64)-1, &ins, 0);
		if (ret) {
		BUG_ON(ret > 0);