From: Yan, Zheng Date: Mon, 21 Sep 2009 19:56:00 +0000 (-0400) Subject: Btrfs: do not reuse objectid of deleted snapshot/subvol X-Git-Tag: v2.6.32-rc1~57^2^2~18 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=13a8a7c8c47e542b3cdb45bec3f431f96af79361;p=linux-block.git Btrfs: do not reuse objectid of deleted snapshot/subvol The new back reference format does not allow reusing objectid of deleted snapshot/subvol. So we use ++highest_objectid to allocate objectid for new snapshot/subvol. Now we use ++highest_objectid to allocate objectid for both new inode and new snapshot/subvolume, so this patch removes 'find hole' code in btrfs_find_free_objectid. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 3b6df7140575..746a9acd2189 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1007,8 +1007,8 @@ struct btrfs_root { u32 stripesize; u32 type; - u64 highest_inode; - u64 last_inode_alloc; + + u64 highest_objectid; int ref_cows; int track_dirty; u64 defrag_trans_start; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 16dae122dda4..790f4b61a3d7 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -895,8 +895,7 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize, root->fs_info = fs_info; root->objectid = objectid; root->last_trans = 0; - root->highest_inode = 0; - root->last_inode_alloc = 0; + root->highest_objectid = 0; root->name = NULL; root->in_sysfs = 0; root->inode_tree.rb_node = NULL; @@ -1095,7 +1094,6 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root, struct btrfs_fs_info *fs_info = tree_root->fs_info; struct btrfs_path *path; struct extent_buffer *l; - u64 highest_inode; u64 generation; u32 blocksize; int ret = 0; @@ -1110,7 +1108,7 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root, kfree(root); return ERR_PTR(ret); } - goto insert; + goto out; } __setup_root(tree_root->nodesize, tree_root->leafsize, @@ -1120,39 +1118,30 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root, path = btrfs_alloc_path(); BUG_ON(!path); ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0); - if (ret != 0) { - if (ret > 0) - ret = -ENOENT; - goto out; + if (ret == 0) { + l = path->nodes[0]; + read_extent_buffer(l, &root->root_item, + btrfs_item_ptr_offset(l, path->slots[0]), + sizeof(root->root_item)); + memcpy(&root->root_key, location, sizeof(*location)); } - l = path->nodes[0]; - read_extent_buffer(l, &root->root_item, - btrfs_item_ptr_offset(l, path->slots[0]), - sizeof(root->root_item)); - memcpy(&root->root_key, location, sizeof(*location)); - ret = 0; -out: - btrfs_release_path(root, path); btrfs_free_path(path); if (ret) { - kfree(root); + if (ret > 0) + ret = -ENOENT; return ERR_PTR(ret); } + generation = btrfs_root_generation(&root->root_item); blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item)); root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item), blocksize, generation); root->commit_root = btrfs_root_node(root); BUG_ON(!root->node); -insert: - if (location->objectid != BTRFS_TREE_LOG_OBJECTID) { +out: + if (location->objectid != BTRFS_TREE_LOG_OBJECTID) root->ref_cows = 1; - ret = btrfs_find_highest_inode(root, &highest_inode); - if (ret == 0) { - root->highest_inode = highest_inode; - root->last_inode_alloc = highest_inode; - } - } + return root; } diff --git a/fs/btrfs/inode-item.c b/fs/btrfs/inode-item.c index 6b627c611808..fc6f4a7f6405 100644 --- a/fs/btrfs/inode-item.c +++ b/fs/btrfs/inode-item.c @@ -177,8 +177,6 @@ int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans, ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(struct btrfs_inode_item)); - if (ret == 0 && objectid > root->highest_inode) - root->highest_inode = objectid; return ret; } diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c index 9abbced1123d..c56eb5909172 100644 --- a/fs/btrfs/inode-map.c +++ b/fs/btrfs/inode-map.c @@ -43,9 +43,10 @@ int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid) slot = path->slots[0] - 1; l = path->nodes[0]; btrfs_item_key_to_cpu(l, &found_key, slot); - *objectid = found_key.objectid; + *objectid = max_t(u64, found_key.objectid, + BTRFS_FIRST_FREE_OBJECTID - 1); } else { - *objectid = BTRFS_FIRST_FREE_OBJECTID; + *objectid = BTRFS_FIRST_FREE_OBJECTID - 1; } ret = 0; error: @@ -53,91 +54,27 @@ error: return ret; } -/* - * walks the btree of allocated inodes and find a hole. - */ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 dirid, u64 *objectid) { - struct btrfs_path *path; - struct btrfs_key key; int ret; - int slot = 0; - u64 last_ino = 0; - int start_found; - struct extent_buffer *l; - struct btrfs_key search_key; - u64 search_start = dirid; - mutex_lock(&root->objectid_mutex); - if (root->last_inode_alloc >= BTRFS_FIRST_FREE_OBJECTID && - root->last_inode_alloc < BTRFS_LAST_FREE_OBJECTID) { - *objectid = ++root->last_inode_alloc; - mutex_unlock(&root->objectid_mutex); - return 0; - } - path = btrfs_alloc_path(); - BUG_ON(!path); - search_start = max(search_start, (u64)BTRFS_FIRST_FREE_OBJECTID); - search_key.objectid = search_start; - search_key.type = 0; - search_key.offset = 0; - - start_found = 0; - ret = btrfs_search_slot(trans, root, &search_key, path, 0, 0); - if (ret < 0) - goto error; - while (1) { - l = path->nodes[0]; - slot = path->slots[0]; - if (slot >= btrfs_header_nritems(l)) { - ret = btrfs_next_leaf(root, path); - if (ret == 0) - continue; - if (ret < 0) - goto error; - if (!start_found) { - *objectid = search_start; - start_found = 1; - goto found; - } - *objectid = last_ino > search_start ? - last_ino : search_start; - goto found; - } - btrfs_item_key_to_cpu(l, &key, slot); - if (key.objectid >= search_start) { - if (start_found) { - if (last_ino < search_start) - last_ino = search_start; - if (key.objectid > last_ino) { - *objectid = last_ino; - goto found; - } - } else if (key.objectid > search_start) { - *objectid = search_start; - goto found; - } - } - if (key.objectid >= BTRFS_LAST_FREE_OBJECTID) - break; + if (unlikely(root->highest_objectid < BTRFS_FIRST_FREE_OBJECTID)) { + ret = btrfs_find_highest_inode(root, &root->highest_objectid); + if (ret) + goto out; + } - start_found = 1; - last_ino = key.objectid + 1; - path->slots[0]++; + if (unlikely(root->highest_objectid >= BTRFS_LAST_FREE_OBJECTID)) { + ret = -ENOSPC; + goto out; } - BUG_ON(1); -found: - btrfs_release_path(root, path); - btrfs_free_path(path); - BUG_ON(*objectid < search_start); - mutex_unlock(&root->objectid_mutex); - return 0; -error: - btrfs_release_path(root, path); - btrfs_free_path(path); + + *objectid = ++root->highest_objectid; + ret = 0; +out: mutex_unlock(&root->objectid_mutex); return ret; } diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 81ba6654c332..9e81f3184f24 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3624,9 +3624,6 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, if (ret != 0) goto fail; - if (objectid > root->highest_inode) - root->highest_inode = objectid; - inode->i_uid = current_fsuid(); if (dir && (dir->i_mode & S_ISGID)) { diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index f4a7b62f9bea..6e674d76186d 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -2951,7 +2951,6 @@ int btrfs_recover_log_trees(struct btrfs_root *log_root_tree) struct btrfs_key tmp_key; struct btrfs_root *log; struct btrfs_fs_info *fs_info = log_root_tree->fs_info; - u64 highest_inode; struct walk_control wc = { .process_func = process_one_buffer, .stage = 0, @@ -3010,11 +3009,6 @@ again: path); BUG_ON(ret); } - ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode); - if (ret == 0) { - wc.replay_dest->highest_inode = highest_inode; - wc.replay_dest->last_inode_alloc = highest_inode; - } key.offset = found_key.offset - 1; wc.replay_dest->log_root = NULL;