From 31840ae1a6b433ca0e6a8d341756ff478bbf959e Mon Sep 17 00:00:00 2001 From: Zheng Yan Date: Tue, 23 Sep 2008 13:14:14 -0400 Subject: Btrfs: Full back reference support This patch makes the back reference system to explicit record the location of parent node for all types of extents. The location of parent node is placed into the offset field of backref key. Every time a tree block is balanced, the back references for the affected lower level extents are updated. Signed-off-by: Chris Mason --- fs/btrfs/tree-log.c | 108 ++++++++++++++++++++++++++++------------------------ 1 file changed, 58 insertions(+), 50 deletions(-) (limited to 'fs/btrfs/tree-log.c') diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 56de3fb2d8d5..88bbfd959f18 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -89,9 +89,9 @@ int btrfs_add_log_tree(struct btrfs_trans_handle *trans, int ret; u64 objectid = root->root_key.objectid; - leaf = btrfs_alloc_free_block(trans, root, root->leafsize, + leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0, BTRFS_TREE_LOG_OBJECTID, - 0, 0, 0, 0, 0); + trans->transid, 0, 0, 0); if (IS_ERR(leaf)) { ret = PTR_ERR(leaf); return ret; @@ -433,6 +433,49 @@ insert: trans->transid); } } + + if (overwrite_root && + key->type == BTRFS_EXTENT_DATA_KEY) { + int extent_type; + struct btrfs_file_extent_item *fi; + + fi = (struct btrfs_file_extent_item *)dst_ptr; + extent_type = btrfs_file_extent_type(path->nodes[0], fi); + if (extent_type == BTRFS_FILE_EXTENT_REG) { + struct btrfs_key ins; + ins.objectid = btrfs_file_extent_disk_bytenr( + path->nodes[0], fi); + ins.offset = btrfs_file_extent_disk_num_bytes( + path->nodes[0], fi); + ins.type = BTRFS_EXTENT_ITEM_KEY; + + /* + * is this extent already allocated in the extent + * allocation tree? If so, just add a reference + */ + ret = btrfs_lookup_extent(root, ins.objectid, + ins.offset); + if (ret == 0) { + ret = btrfs_inc_extent_ref(trans, root, + ins.objectid, ins.offset, + path->nodes[0]->start, + root->root_key.objectid, + trans->transid, + key->objectid, key->offset); + } else { + /* + * insert the extent pointer in the extent + * allocation tree + */ + ret = btrfs_alloc_logged_extent(trans, root, + path->nodes[0]->start, + root->root_key.objectid, + trans->transid, key->objectid, + key->offset, &ins); + BUG_ON(ret); + } + } + } no_copy: btrfs_mark_buffer_dirty(path->nodes[0]); btrfs_release_path(root, path); @@ -551,45 +594,10 @@ static noinline int replay_one_extent(struct btrfs_trans_handle *trans, start, extent_end, start, &alloc_hint); BUG_ON(ret); + /* insert the extent */ + ret = overwrite_item(trans, root, path, eb, slot, key); BUG_ON(ret); - if (found_type == BTRFS_FILE_EXTENT_REG) { - struct btrfs_key ins; - - ins.objectid = btrfs_file_extent_disk_bytenr(eb, item); - ins.offset = btrfs_file_extent_disk_num_bytes(eb, item); - ins.type = BTRFS_EXTENT_ITEM_KEY; - - /* insert the extent pointer in the file */ - ret = overwrite_item(trans, root, path, eb, slot, key); - BUG_ON(ret); - /* - * is this extent already allocated in the extent - * allocation tree? If so, just add a reference - */ - ret = btrfs_lookup_extent(root, path, ins.objectid, ins.offset); - btrfs_release_path(root, path); - if (ret == 0) { - ret = btrfs_inc_extent_ref(trans, root, - ins.objectid, ins.offset, - root->root_key.objectid, - trans->transid, key->objectid, start); - } else { - /* - * insert the extent pointer in the extent - * allocation tree - */ - ret = btrfs_alloc_logged_extent(trans, root, - root->root_key.objectid, - trans->transid, key->objectid, - start, &ins); - BUG_ON(ret); - } - } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { - /* inline extents are easy, we just overwrite them */ - ret = overwrite_item(trans, root, path, eb, slot, key); - BUG_ON(ret); - } /* btrfs_drop_extents changes i_blocks, update it here */ inode->i_blocks += (extent_end - start) >> 9; btrfs_update_inode(trans, root, inode); @@ -1806,16 +1814,14 @@ static int noinline walk_up_log_tree(struct btrfs_trans_handle *trans, WARN_ON(*level == 0); return 0; } else { - if (path->nodes[*level] == root->node) { - root_owner = root->root_key.objectid; - root_gen = - btrfs_header_generation(path->nodes[*level]); - } else { - struct extent_buffer *node; - node = path->nodes[*level + 1]; - root_owner = btrfs_header_owner(node); - root_gen = btrfs_header_generation(node); - } + struct extent_buffer *parent; + if (path->nodes[*level] == root->node) + parent = path->nodes[*level]; + else + parent = path->nodes[*level + 1]; + + root_owner = btrfs_header_owner(parent); + root_gen = btrfs_header_generation(parent); wc->process_func(root, path->nodes[*level], wc, btrfs_header_generation(path->nodes[*level])); if (wc->free) { @@ -2525,8 +2531,10 @@ static noinline int copy_items(struct btrfs_trans_handle *trans, if (ds != 0) { ret = btrfs_inc_extent_ref(trans, log, ds, dl, + dst_path->nodes[0]->start, BTRFS_TREE_LOG_OBJECTID, - 0, ins_keys[i].objectid, + trans->transid, + ins_keys[i].objectid, ins_keys[i].offset); BUG_ON(ret); } -- cgit v1.2.3