From 4df27c4d5cc1dda54ed7d0a8389347f2df359cf9 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Mon, 21 Sep 2009 15:56:00 -0400 Subject: Btrfs: change how subvolumes are organized btrfs allows subvolumes and snapshots anywhere in the directory tree. If we snapshot a subvolume that contains a link to other subvolume called subvolA, subvolA can be accessed through both the original subvolume and the snapshot. This is similar to creating hard link to directory, and has the very similar problems. The aim of this patch is enforcing there is only one access point to each subvolume. Only the first directory entry (the one added when the subvolume/snapshot was created) is treated as valid access point. The first directory entry is distinguished by checking root forward reference. If the corresponding root forward reference is missing, we know the entry is not the first one. This patch also adds snapshot/subvolume rename support, the code allows rename subvolume link across subvolumes. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/root-tree.c | 69 ++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 51 insertions(+), 18 deletions(-) (limited to 'fs/btrfs/root-tree.c') diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c index 0ddc6d61c55..5ef72599a58 100644 --- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -278,31 +278,57 @@ out: return ret; } -#if 0 /* this will get used when snapshot deletion is implemented */ int btrfs_del_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *tree_root, - u64 root_id, u8 type, u64 ref_id) + u64 root_id, u64 ref_id, u64 dirid, u64 *sequence, + const char *name, int name_len) + { + struct btrfs_path *path; + struct btrfs_root_ref *ref; + struct extent_buffer *leaf; struct btrfs_key key; + unsigned long ptr; + int err = 0; int ret; - struct btrfs_path *path; path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; key.objectid = root_id; - key.type = type; + key.type = BTRFS_ROOT_BACKREF_KEY; key.offset = ref_id; - +again: ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1); - BUG_ON(ret); - - ret = btrfs_del_item(trans, tree_root, path); - BUG_ON(ret); + BUG_ON(ret < 0); + if (ret == 0) { + leaf = path->nodes[0]; + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_root_ref); + + WARN_ON(btrfs_root_ref_dirid(leaf, ref) != dirid); + WARN_ON(btrfs_root_ref_name_len(leaf, ref) != name_len); + ptr = (unsigned long)(ref + 1); + WARN_ON(memcmp_extent_buffer(leaf, name, ptr, name_len)); + *sequence = btrfs_root_ref_sequence(leaf, ref); + + ret = btrfs_del_item(trans, tree_root, path); + BUG_ON(ret); + } else + err = -ENOENT; + + if (key.type == BTRFS_ROOT_BACKREF_KEY) { + btrfs_release_path(tree_root, path); + key.objectid = ref_id; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = root_id; + goto again; + } btrfs_free_path(path); - return ret; + return err; } -#endif int btrfs_find_root_ref(struct btrfs_root *tree_root, struct btrfs_path *path, @@ -319,7 +345,6 @@ int btrfs_find_root_ref(struct btrfs_root *tree_root, return ret; } - /* * add a btrfs_root_ref item. type is either BTRFS_ROOT_REF_KEY * or BTRFS_ROOT_BACKREF_KEY. @@ -335,8 +360,7 @@ int btrfs_find_root_ref(struct btrfs_root *tree_root, */ int btrfs_add_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *tree_root, - u64 root_id, u8 type, u64 ref_id, - u64 dirid, u64 sequence, + u64 root_id, u64 ref_id, u64 dirid, u64 sequence, const char *name, int name_len) { struct btrfs_key key; @@ -346,13 +370,14 @@ int btrfs_add_root_ref(struct btrfs_trans_handle *trans, struct extent_buffer *leaf; unsigned long ptr; - path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; key.objectid = root_id; - key.type = type; + key.type = BTRFS_ROOT_BACKREF_KEY; key.offset = ref_id; - +again: ret = btrfs_insert_empty_item(trans, tree_root, path, &key, sizeof(*ref) + name_len); BUG_ON(ret); @@ -366,6 +391,14 @@ int btrfs_add_root_ref(struct btrfs_trans_handle *trans, write_extent_buffer(leaf, name, ptr, name_len); btrfs_mark_buffer_dirty(leaf); + if (key.type == BTRFS_ROOT_BACKREF_KEY) { + btrfs_release_path(tree_root, path); + key.objectid = ref_id; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = root_id; + goto again; + } + btrfs_free_path(path); - return ret; + return 0; } -- cgit v1.2.3-70-g09d2 From 76dda93c6ae2c1dc3e6cde34569d6aca26b0c918 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Mon, 21 Sep 2009 16:00:26 -0400 Subject: Btrfs: add snapshot/subvolume destroy ioctl This patch adds snapshot/subvolume destroy ioctl. A subvolume that isn't being used and doesn't contains links to other subvolumes can be destroyed. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 12 +- fs/btrfs/disk-io.c | 81 ++++++++++--- fs/btrfs/export.c | 133 ++++++++++++-------- fs/btrfs/extent-tree.c | 21 +++- fs/btrfs/inode.c | 134 +++++++++++++++++++-- fs/btrfs/ioctl.c | 320 ++++++++++++++++++++++++++++--------------------- fs/btrfs/ioctl.h | 3 +- fs/btrfs/relocation.c | 41 ++++++- fs/btrfs/root-tree.c | 69 ++++++++++- fs/btrfs/super.c | 1 + fs/btrfs/transaction.c | 10 +- fs/btrfs/tree-log.c | 13 +- 12 files changed, 605 insertions(+), 233 deletions(-) (limited to 'fs/btrfs/root-tree.c') diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 6ade48b227e..bc57e236ac6 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -839,9 +839,7 @@ struct btrfs_fs_info { struct mutex transaction_kthread_mutex; struct mutex cleaner_mutex; struct mutex chunk_mutex; - struct mutex drop_mutex; struct mutex volume_mutex; - struct mutex tree_reloc_mutex; /* * this protects the ordered operations list only while we are * processing all of the entries on it. This way we make @@ -852,6 +850,10 @@ struct btrfs_fs_info { struct mutex ordered_operations_mutex; struct rw_semaphore extent_commit_sem; + struct rw_semaphore subvol_sem; + + struct srcu_struct subvol_srcu; + struct list_head trans_list; struct list_head hashers; struct list_head dead_roots; @@ -2142,6 +2144,7 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct int btrfs_search_root(struct btrfs_root *root, u64 search_start, u64 *found_objectid); int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid); +int btrfs_find_orphan_roots(struct btrfs_root *tree_root); int btrfs_set_root_node(struct btrfs_root_item *item, struct extent_buffer *node); /* dir-item.c */ @@ -2273,7 +2276,7 @@ int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end); int btrfs_writepages(struct address_space *mapping, struct writeback_control *wbc); int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, - struct btrfs_root *new_root, struct dentry *dentry, + struct btrfs_root *new_root, u64 new_dirid, u64 alloc_hint); int btrfs_merge_bio_hook(struct page *page, unsigned long offset, size_t size, struct bio *bio, unsigned long bio_flags); @@ -2289,6 +2292,7 @@ int btrfs_write_inode(struct inode *inode, int wait); void btrfs_dirty_inode(struct inode *inode); struct inode *btrfs_alloc_inode(struct super_block *sb); void btrfs_destroy_inode(struct inode *inode); +void btrfs_drop_inode(struct inode *inode); int btrfs_init_cachep(void); void btrfs_destroy_cachep(void); long btrfs_ioctl_trans_end(struct file *file); @@ -2306,6 +2310,8 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode); int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode); void btrfs_orphan_cleanup(struct btrfs_root *root); int btrfs_cont_expand(struct inode *inode, loff_t size); +int btrfs_invalidate_inodes(struct btrfs_root *root); +extern struct dentry_operations btrfs_dentry_operations; /* ioctl.c */ long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg); diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index a4f531047c4..a0d41e713f3 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1378,8 +1378,10 @@ static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi) err = bdi_register(bdi, NULL, "btrfs-%d", atomic_inc_return(&btrfs_bdi_num)); - if (err) + if (err) { + bdi_destroy(bdi); return err; + } bdi->ra_pages = default_backing_dev_info.ra_pages; bdi->unplug_io_fn = btrfs_unplug_io_fn; @@ -1469,9 +1471,12 @@ static int cleaner_kthread(void *arg) break; vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE); - mutex_lock(&root->fs_info->cleaner_mutex); - btrfs_clean_old_snapshots(root); - mutex_unlock(&root->fs_info->cleaner_mutex); + + if (!(root->fs_info->sb->s_flags & MS_RDONLY) && + mutex_trylock(&root->fs_info->cleaner_mutex)) { + btrfs_clean_old_snapshots(root); + mutex_unlock(&root->fs_info->cleaner_mutex); + } if (freezing(current)) { refrigerator(); @@ -1576,7 +1581,26 @@ struct btrfs_root *open_ctree(struct super_block *sb, err = -ENOMEM; goto fail; } - INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS); + + ret = init_srcu_struct(&fs_info->subvol_srcu); + if (ret) { + err = ret; + goto fail; + } + + ret = setup_bdi(fs_info, &fs_info->bdi); + if (ret) { + err = ret; + goto fail_srcu; + } + + fs_info->btree_inode = new_inode(sb); + if (!fs_info->btree_inode) { + err = -ENOMEM; + goto fail_bdi; + } + + INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC); INIT_LIST_HEAD(&fs_info->trans_list); INIT_LIST_HEAD(&fs_info->dead_roots); INIT_LIST_HEAD(&fs_info->hashers); @@ -1586,6 +1610,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, spin_lock_init(&fs_info->delalloc_lock); spin_lock_init(&fs_info->new_trans_lock); spin_lock_init(&fs_info->ref_cache_lock); + spin_lock_init(&fs_info->fs_roots_radix_lock); init_completion(&fs_info->kobj_unregister); fs_info->tree_root = tree_root; @@ -1604,11 +1629,6 @@ struct btrfs_root *open_ctree(struct super_block *sb, fs_info->sb = sb; fs_info->max_extent = (u64)-1; fs_info->max_inline = 8192 * 1024; - if (setup_bdi(fs_info, &fs_info->bdi)) - goto fail_bdi; - fs_info->btree_inode = new_inode(sb); - fs_info->btree_inode->i_ino = 1; - fs_info->btree_inode->i_nlink = 1; fs_info->metadata_ratio = 8; fs_info->thread_pool_size = min_t(unsigned long, @@ -1620,6 +1640,8 @@ struct btrfs_root *open_ctree(struct super_block *sb, sb->s_blocksize = 4096; sb->s_blocksize_bits = blksize_bits(4096); + fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID; + fs_info->btree_inode->i_nlink = 1; /* * we set the i_size on the btree inode to the max possible int. * the real end of the address space is determined by all of @@ -1638,6 +1660,11 @@ struct btrfs_root *open_ctree(struct super_block *sb, BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops; + BTRFS_I(fs_info->btree_inode)->root = tree_root; + memset(&BTRFS_I(fs_info->btree_inode)->location, 0, + sizeof(struct btrfs_key)); + BTRFS_I(fs_info->btree_inode)->dummy_inode = 1; + spin_lock_init(&fs_info->block_group_cache_lock); fs_info->block_group_cache_tree.rb_node = NULL; @@ -1648,21 +1675,16 @@ struct btrfs_root *open_ctree(struct super_block *sb, fs_info->pinned_extents = &fs_info->freed_extents[0]; fs_info->do_barriers = 1; - BTRFS_I(fs_info->btree_inode)->root = tree_root; - memset(&BTRFS_I(fs_info->btree_inode)->location, 0, - sizeof(struct btrfs_key)); - insert_inode_hash(fs_info->btree_inode); mutex_init(&fs_info->trans_mutex); mutex_init(&fs_info->ordered_operations_mutex); mutex_init(&fs_info->tree_log_mutex); - mutex_init(&fs_info->drop_mutex); mutex_init(&fs_info->chunk_mutex); mutex_init(&fs_info->transaction_kthread_mutex); mutex_init(&fs_info->cleaner_mutex); mutex_init(&fs_info->volume_mutex); - mutex_init(&fs_info->tree_reloc_mutex); init_rwsem(&fs_info->extent_commit_sem); + init_rwsem(&fs_info->subvol_sem); btrfs_init_free_cluster(&fs_info->meta_alloc_cluster); btrfs_init_free_cluster(&fs_info->data_alloc_cluster); @@ -1941,6 +1963,9 @@ printk("thread pool is %d\n", fs_info->thread_pool_size); } } + ret = btrfs_find_orphan_roots(tree_root); + BUG_ON(ret); + if (!(sb->s_flags & MS_RDONLY)) { ret = btrfs_recover_relocation(tree_root); BUG_ON(ret); @@ -2000,6 +2025,8 @@ fail_iput: btrfs_mapping_tree_free(&fs_info->mapping_tree); fail_bdi: bdi_destroy(&fs_info->bdi); +fail_srcu: + cleanup_srcu_struct(&fs_info->subvol_srcu); fail: kfree(extent_root); kfree(tree_root); @@ -2263,6 +2290,10 @@ int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root) radix_tree_delete(&fs_info->fs_roots_radix, (unsigned long)root->root_key.objectid); spin_unlock(&fs_info->fs_roots_radix_lock); + + if (btrfs_root_refs(&root->root_item) == 0) + synchronize_srcu(&fs_info->subvol_srcu); + free_fs_root(root); return 0; } @@ -2286,6 +2317,20 @@ static int del_fs_roots(struct btrfs_fs_info *fs_info) struct btrfs_root *gang[8]; int i; + while (!list_empty(&fs_info->dead_roots)) { + gang[0] = list_entry(fs_info->dead_roots.next, + struct btrfs_root, root_list); + list_del(&gang[0]->root_list); + + if (gang[0]->in_radix) { + btrfs_free_fs_root(fs_info, gang[0]); + } else { + free_extent_buffer(gang[0]->node); + free_extent_buffer(gang[0]->commit_root); + kfree(gang[0]); + } + } + while (1) { ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix, (void **)gang, 0, @@ -2315,9 +2360,6 @@ int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info) root_objectid = gang[ret - 1]->root_key.objectid + 1; for (i = 0; i < ret; i++) { root_objectid = gang[i]->root_key.objectid; - ret = btrfs_find_dead_roots(fs_info->tree_root, - root_objectid); - BUG_ON(ret); btrfs_orphan_cleanup(gang[i]); } root_objectid++; @@ -2405,6 +2447,7 @@ int close_ctree(struct btrfs_root *root) btrfs_mapping_tree_free(&fs_info->mapping_tree); bdi_destroy(&fs_info->bdi); + cleanup_srcu_struct(&fs_info->subvol_srcu); kfree(fs_info->extent_root); kfree(fs_info->tree_root); diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c index 9596b40caa4..ba5c3fd5ab8 100644 --- a/fs/btrfs/export.c +++ b/fs/btrfs/export.c @@ -28,7 +28,7 @@ static int btrfs_encode_fh(struct dentry *dentry, u32 *fh, int *max_len, len = BTRFS_FID_SIZE_NON_CONNECTABLE; type = FILEID_BTRFS_WITHOUT_PARENT; - fid->objectid = BTRFS_I(inode)->location.objectid; + fid->objectid = inode->i_ino; fid->root_objectid = BTRFS_I(inode)->root->objectid; fid->gen = inode->i_generation; @@ -60,34 +60,61 @@ static int btrfs_encode_fh(struct dentry *dentry, u32 *fh, int *max_len, } static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid, - u64 root_objectid, u32 generation) + u64 root_objectid, u32 generation, + int check_generation) { + struct btrfs_fs_info *fs_info = btrfs_sb(sb)->fs_info; struct btrfs_root *root; + struct dentry *dentry; struct inode *inode; struct btrfs_key key; + int index; + int err = 0; + + if (objectid < BTRFS_FIRST_FREE_OBJECTID) + return ERR_PTR(-ESTALE); key.objectid = root_objectid; btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); key.offset = (u64)-1; - root = btrfs_read_fs_root_no_name(btrfs_sb(sb)->fs_info, &key); - if (IS_ERR(root)) - return ERR_CAST(root); + index = srcu_read_lock(&fs_info->subvol_srcu); + + root = btrfs_read_fs_root_no_name(fs_info, &key); + if (IS_ERR(root)) { + err = PTR_ERR(root); + goto fail; + } + + if (btrfs_root_refs(&root->root_item) == 0) { + err = -ENOENT; + goto fail; + } key.objectid = objectid; btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); key.offset = 0; inode = btrfs_iget(sb, &key, root); - if (IS_ERR(inode)) - return (void *)inode; + if (IS_ERR(inode)) { + err = PTR_ERR(inode); + goto fail; + } + + srcu_read_unlock(&fs_info->subvol_srcu, index); - if (generation != inode->i_generation) { + if (check_generation && generation != inode->i_generation) { iput(inode); return ERR_PTR(-ESTALE); } - return d_obtain_alias(inode); + dentry = d_obtain_alias(inode); + if (!IS_ERR(dentry)) + dentry->d_op = &btrfs_dentry_operations; + return dentry; +fail: + srcu_read_unlock(&fs_info->subvol_srcu, index); + return ERR_PTR(err); } static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh, @@ -111,7 +138,7 @@ static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh, objectid = fid->parent_objectid; generation = fid->parent_gen; - return btrfs_get_dentry(sb, objectid, root_objectid, generation); + return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1); } static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh, @@ -133,66 +160,76 @@ static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh, root_objectid = fid->root_objectid; generation = fid->gen; - return btrfs_get_dentry(sb, objectid, root_objectid, generation); + return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1); } static struct dentry *btrfs_get_parent(struct dentry *child) { struct inode *dir = child->d_inode; + static struct dentry *dentry; struct btrfs_root *root = BTRFS_I(dir)->root; - struct btrfs_key key; struct btrfs_path *path; struct extent_buffer *leaf; - int slot; - u64 objectid; + struct btrfs_root_ref *ref; + struct btrfs_key key; + struct btrfs_key found_key; int ret; path = btrfs_alloc_path(); - key.objectid = dir->i_ino; - btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY); - key.offset = (u64)-1; + if (dir->i_ino == BTRFS_FIRST_FREE_OBJECTID) { + key.objectid = root->root_key.objectid; + key.type = BTRFS_ROOT_BACKREF_KEY; + key.offset = (u64)-1; + root = root->fs_info->tree_root; + } else { + key.objectid = dir->i_ino; + key.type = BTRFS_INODE_REF_KEY; + key.offset = (u64)-1; + } ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); - if (ret < 0) { - /* Error */ - btrfs_free_path(path); - return ERR_PTR(ret); + if (ret < 0) + goto fail; + + BUG_ON(ret == 0); + if (path->slots[0] == 0) { + ret = -ENOENT; + goto fail; } + + path->slots[0]--; leaf = path->nodes[0]; - slot = path->slots[0]; - if (ret) { - /* btrfs_search_slot() returns the slot where we'd want to - insert a backref for parent inode #0xFFFFFFFFFFFFFFFF. - The _real_ backref, telling us what the parent inode - _actually_ is, will be in the slot _before_ the one - that btrfs_search_slot() returns. */ - if (!slot) { - /* Unless there is _no_ key in the tree before... */ - btrfs_free_path(path); - return ERR_PTR(-EIO); - } - slot--; + + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.objectid != key.objectid || found_key.type != key.type) { + ret = -ENOENT; + goto fail; } - btrfs_item_key_to_cpu(leaf, &key, slot); + if (found_key.type == BTRFS_ROOT_BACKREF_KEY) { + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_root_ref); + key.objectid = btrfs_root_ref_dirid(leaf, ref); + } else { + key.objectid = found_key.offset; + } btrfs_free_path(path); - if (key.objectid != dir->i_ino || key.type != BTRFS_INODE_REF_KEY) - return ERR_PTR(-EINVAL); - - objectid = key.offset; - - /* If we are already at the root of a subvol, return the real root */ - if (objectid == dir->i_ino) - return dget(dir->i_sb->s_root); + if (found_key.type == BTRFS_ROOT_BACKREF_KEY) { + return btrfs_get_dentry(root->fs_info->sb, key.objectid, + found_key.offset, 0, 0); + } - /* Build a new key for the inode item */ - key.objectid = objectid; - btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); + key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; - - return d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root)); + dentry = d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root)); + if (!IS_ERR(dentry)) + dentry->d_op = &btrfs_dentry_operations; + return dentry; +fail: + btrfs_free_path(path); + return ERR_PTR(ret); } const struct export_operations btrfs_export_ops = { diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 8fc92298218..4bd04f3fa8b 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -5463,9 +5463,24 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref) ret = btrfs_del_root(trans, tree_root, &root->root_key); BUG_ON(ret); - free_extent_buffer(root->node); - free_extent_buffer(root->commit_root); - kfree(root); + if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { + ret = btrfs_find_last_root(tree_root, root->root_key.objectid, + NULL, NULL); + BUG_ON(ret < 0); + if (ret > 0) { + ret = btrfs_del_orphan_item(trans, tree_root, + root->root_key.objectid); + BUG_ON(ret); + } + } + + if (root->in_radix) { + btrfs_free_fs_root(tree_root->fs_info, root); + } else { + free_extent_buffer(root->node); + free_extent_buffer(root->commit_root); + kfree(root); + } out: btrfs_end_transaction(trans, tree_root); kfree(wc); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 6036b36789c..db9cbd91eb4 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3089,6 +3089,11 @@ void btrfs_delete_inode(struct inode *inode) } btrfs_wait_ordered_range(inode, 0, (u64)-1); + if (inode->i_nlink > 0) { + BUG_ON(btrfs_root_refs(&root->root_item) != 0); + goto no_delete; + } + btrfs_i_size_write(inode, 0); trans = btrfs_join_transaction(root, 1); @@ -3225,11 +3230,13 @@ static void inode_tree_add(struct inode *inode) struct btrfs_inode *entry; struct rb_node **p; struct rb_node *parent; - again: p = &root->inode_tree.rb_node; parent = NULL; + if (hlist_unhashed(&inode->i_hash)) + return; + spin_lock(&root->inode_lock); while (*p) { parent = *p; @@ -3256,13 +3263,87 @@ again: static void inode_tree_del(struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; + int empty = 0; spin_lock(&root->inode_lock); if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree); RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); + empty = RB_EMPTY_ROOT(&root->inode_tree); } spin_unlock(&root->inode_lock); + + if (empty && btrfs_root_refs(&root->root_item) == 0) { + synchronize_srcu(&root->fs_info->subvol_srcu); + spin_lock(&root->inode_lock); + empty = RB_EMPTY_ROOT(&root->inode_tree); + spin_unlock(&root->inode_lock); + if (empty) + btrfs_add_dead_root(root); + } +} + +int btrfs_invalidate_inodes(struct btrfs_root *root) +{ + struct rb_node *node; + struct rb_node *prev; + struct btrfs_inode *entry; + struct inode *inode; + u64 objectid = 0; + + WARN_ON(btrfs_root_refs(&root->root_item) != 0); + + spin_lock(&root->inode_lock); +again: + node = root->inode_tree.rb_node; + prev = NULL; + while (node) { + prev = node; + entry = rb_entry(node, struct btrfs_inode, rb_node); + + if (objectid < entry->vfs_inode.i_ino) + node = node->rb_left; + else if (objectid > entry->vfs_inode.i_ino) + node = node->rb_right; + else + break; + } + if (!node) { + while (prev) { + entry = rb_entry(prev, struct btrfs_inode, rb_node); + if (objectid <= entry->vfs_inode.i_ino) { + node = prev; + break; + } + prev = rb_next(prev); + } + } + while (node) { + entry = rb_entry(node, struct btrfs_inode, rb_node); + objectid = entry->vfs_inode.i_ino + 1; + inode = igrab(&entry->vfs_inode); + if (inode) { + spin_unlock(&root->inode_lock); + if (atomic_read(&inode->i_count) > 1) + d_prune_aliases(inode); + /* + * btrfs_drop_inode will remove it from + * the inode cache when its usage count + * hits zero. + */ + iput(inode); + cond_resched(); + spin_lock(&root->inode_lock); + goto again; + } + + if (cond_resched_lock(&root->inode_lock)) + goto again; + + node = rb_next(node); + } + spin_unlock(&root->inode_lock); + return 0; } static noinline void init_btrfs_i(struct inode *inode) @@ -3379,8 +3460,11 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_root *sub_root = root; struct btrfs_key location; + int index; int ret; + dentry->d_op = &btrfs_dentry_operations; + if (dentry->d_name.len > BTRFS_NAME_LEN) return ERR_PTR(-ENAMETOOLONG); @@ -3399,6 +3483,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); + index = srcu_read_lock(&root->fs_info->subvol_srcu); ret = fixup_tree_root_location(root, dir, dentry, &location, &sub_root); if (ret < 0) { @@ -3409,9 +3494,24 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) } else { inode = btrfs_iget(dir->i_sb, &location, sub_root); } + srcu_read_unlock(&root->fs_info->subvol_srcu, index); + return inode; } +static int btrfs_dentry_delete(struct dentry *dentry) +{ + struct btrfs_root *root; + + if (!dentry->d_inode) + return 0; + + root = BTRFS_I(dentry->d_inode)->root; + if (btrfs_root_refs(&root->root_item) == 0) + return 1; + return 0; +} + static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) { @@ -4773,11 +4873,11 @@ out: * create a new subvolume directory/inode (helper for the ioctl). */ int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, - struct btrfs_root *new_root, struct dentry *dentry, + struct btrfs_root *new_root, u64 new_dirid, u64 alloc_hint) { struct inode *inode; - int error; + int err; u64 index = 0; inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid, @@ -4790,11 +4890,10 @@ int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, inode->i_nlink = 1; btrfs_i_size_write(inode, 0); - error = btrfs_update_inode(trans, new_root, inode); - if (error) - return error; + err = btrfs_update_inode(trans, new_root, inode); + BUG_ON(err); - d_instantiate(dentry, inode); + iput(inode); return 0; } @@ -4872,6 +4971,16 @@ void btrfs_destroy_inode(struct inode *inode) kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); } +void btrfs_drop_inode(struct inode *inode) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + + if (inode->i_nlink > 0 && btrfs_root_refs(&root->root_item) == 0) + generic_delete_inode(inode); + else + generic_drop_inode(inode); +} + static void init_once(void *foo) { struct btrfs_inode *ei = (struct btrfs_inode *) foo; @@ -4973,6 +5082,10 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT) filemap_flush(old_inode->i_mapping); + /* close the racy window with snapshot create/destroy ioctl */ + if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) + down_read(&root->fs_info->subvol_sem); + trans = btrfs_start_transaction(root, 1); if (dest != root) @@ -5062,6 +5175,8 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, btrfs_end_transaction_throttle(trans, root); + if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) + up_read(&root->fs_info->subvol_sem); return ret; } @@ -5420,6 +5535,7 @@ static struct inode_operations btrfs_dir_ro_inode_operations = { .lookup = btrfs_lookup, .permission = btrfs_permission, }; + static struct file_operations btrfs_dir_file_operations = { .llseek = generic_file_llseek, .read = generic_read_dir, @@ -5506,3 +5622,7 @@ static struct inode_operations btrfs_symlink_inode_operations = { .listxattr = btrfs_listxattr, .removexattr = btrfs_removexattr, }; + +struct dentry_operations btrfs_dentry_operations = { + .d_delete = btrfs_dentry_delete, +}; diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 9b3a88755e5..a13fd556db7 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -230,8 +230,8 @@ static noinline int create_subvol(struct btrfs_root *root, struct btrfs_root_item root_item; struct btrfs_inode_item *inode_item; struct extent_buffer *leaf; - struct btrfs_root *new_root = root; - struct inode *dir; + struct btrfs_root *new_root; + struct inode *dir = dentry->d_parent->d_inode; int ret; int err; u64 objectid; @@ -241,7 +241,7 @@ static noinline int create_subvol(struct btrfs_root *root, ret = btrfs_check_metadata_free_space(root); if (ret) - goto fail_commit; + return ret; trans = btrfs_start_transaction(root, 1); BUG_ON(!trans); @@ -304,11 +304,17 @@ static noinline int create_subvol(struct btrfs_root *root, if (ret) goto fail; + key.offset = (u64)-1; + new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); + BUG_ON(IS_ERR(new_root)); + + btrfs_record_root_in_trans(trans, new_root); + + ret = btrfs_create_subvol_root(trans, new_root, new_dirid, + BTRFS_I(dir)->block_group); /* * insert the directory item */ - key.offset = (u64)-1; - dir = dentry->d_parent->d_inode; ret = btrfs_set_inode_index(dir, &index); BUG_ON(ret); @@ -325,30 +331,15 @@ static noinline int create_subvol(struct btrfs_root *root, ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, objectid, root->root_key.objectid, dir->i_ino, index, name, namelen); - BUG_ON(ret); - ret = btrfs_commit_transaction(trans, root); - if (ret) - goto fail_commit; - - new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); - BUG_ON(!new_root); - - trans = btrfs_start_transaction(new_root, 1); - BUG_ON(!trans); - - ret = btrfs_create_subvol_root(trans, new_root, dentry, new_dirid, - BTRFS_I(dir)->block_group); - if (ret) - goto fail; + BUG_ON(ret); + d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry)); fail: nr = trans->blocks_used; - err = btrfs_commit_transaction(trans, new_root); + err = btrfs_commit_transaction(trans, root); if (err && !ret) ret = err; -fail_commit: - btrfs_btree_balance_dirty(root, nr); return ret; } @@ -409,14 +400,15 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child) * sys_mkdirat and vfs_mkdir, but we only do a single component lookup * inside this filesystem so it's quite a bit simpler. */ -static noinline int btrfs_mksubvol(struct path *parent, char *name, - int mode, int namelen, +static noinline int btrfs_mksubvol(struct path *parent, + char *name, int namelen, struct btrfs_root *snap_src) { + struct inode *dir = parent->dentry->d_inode; struct dentry *dentry; int error; - mutex_lock_nested(&parent->dentry->d_inode->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); dentry = lookup_one_len(name, parent->dentry, namelen); error = PTR_ERR(dentry); @@ -427,99 +419,39 @@ static noinline int btrfs_mksubvol(struct path *parent, char *name, if (dentry->d_inode) goto out_dput; - if (!IS_POSIXACL(parent->dentry->d_inode)) - mode &= ~current_umask(); - error = mnt_want_write(parent->mnt); if (error) goto out_dput; - error = btrfs_may_create(parent->dentry->d_inode, dentry); + error = btrfs_may_create(dir, dentry); if (error) goto out_drop_write; - /* - * Actually perform the low-level subvolume creation after all - * this VFS fuzz. - * - * Eventually we want to pass in an inode under which we create this - * subvolume, but for now all are under the filesystem root. - * - * Also we should pass on the mode eventually to allow creating new - * subvolume with specific mode bits. - */ + down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); + + if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) + goto out_up_read; + if (snap_src) { - struct dentry *dir = dentry->d_parent; - struct dentry *test = dir->d_parent; - struct btrfs_path *path = btrfs_alloc_path(); - int ret; - u64 test_oid; - u64 parent_oid = BTRFS_I(dir->d_inode)->root->root_key.objectid; - - test_oid = snap_src->root_key.objectid; - - ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, - path, parent_oid, test_oid); - if (ret == 0) - goto create; - btrfs_release_path(snap_src->fs_info->tree_root, path); - - /* we need to make sure we aren't creating a directory loop - * by taking a snapshot of something that has our current - * subvol in its directory tree. So, this loops through - * the dentries and checks the forward refs for each subvolume - * to see if is references the subvolume where we are - * placing this new snapshot. - */ - while (1) { - if (!test || - dir == snap_src->fs_info->sb->s_root || - test == snap_src->fs_info->sb->s_root || - test->d_inode->i_sb != snap_src->fs_info->sb) { - break; - } - if (S_ISLNK(test->d_inode->i_mode)) { - printk(KERN_INFO "Btrfs symlink in snapshot " - "path, failed\n"); - error = -EMLINK; - btrfs_free_path(path); - goto out_drop_write; - } - test_oid = - BTRFS_I(test->d_inode)->root->root_key.objectid; - ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, - path, test_oid, parent_oid); - if (ret == 0) { - printk(KERN_INFO "Btrfs snapshot creation " - "failed, looping\n"); - error = -EMLINK; - btrfs_free_path(path); - goto out_drop_write; - } - btrfs_release_path(snap_src->fs_info->tree_root, path); - test = test->d_parent; - } -create: - btrfs_free_path(path); - error = create_snapshot(snap_src, dentry, name, namelen); + error = create_snapshot(snap_src, dentry, + name, namelen); } else { - error = create_subvol(BTRFS_I(parent->dentry->d_inode)->root, - dentry, name, namelen); + error = create_subvol(BTRFS_I(dir)->root, dentry, + name, namelen); } - if (error) - goto out_drop_write; - - fsnotify_mkdir(parent->dentry->d_inode, dentry); + if (!error) + fsnotify_mkdir(dir, dentry); +out_up_read: + up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); out_drop_write: mnt_drop_write(parent->mnt); out_dput: dput(dentry); out_unlock: - mutex_unlock(&parent->dentry->d_inode->i_mutex); + mutex_unlock(&dir->i_mutex); return error; } - static int btrfs_defrag_file(struct file *file) { struct inode *inode = fdentry(file)->d_inode; @@ -597,7 +529,8 @@ out_unlock: return 0; } -static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg) +static noinline int btrfs_ioctl_resize(struct btrfs_root *root, + void __user *arg) { u64 new_size; u64 old_size; @@ -706,10 +639,7 @@ static noinline int btrfs_ioctl_snap_create(struct file *file, { struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; struct btrfs_ioctl_vol_args *vol_args; - struct btrfs_dir_item *di; - struct btrfs_path *path; struct file *src_file; - u64 root_dirid; int namelen; int ret = 0; @@ -727,32 +657,9 @@ static noinline int btrfs_ioctl_snap_create(struct file *file, goto out; } - path = btrfs_alloc_path(); - if (!path) { - ret = -ENOMEM; - goto out; - } - - root_dirid = root->fs_info->sb->s_root->d_inode->i_ino, - di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, - path, root_dirid, - vol_args->name, namelen, 0); - btrfs_free_path(path); - - if (di && !IS_ERR(di)) { - ret = -EEXIST; - goto out; - } - - if (IS_ERR(di)) { - ret = PTR_ERR(di); - goto out; - } - if (subvol) { - ret = btrfs_mksubvol(&file->f_path, vol_args->name, - file->f_path.dentry->d_inode->i_mode, - namelen, NULL); + ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen, + NULL); } else { struct inode *src_inode; src_file = fget(vol_args->fd); @@ -769,17 +676,156 @@ static noinline int btrfs_ioctl_snap_create(struct file *file, fput(src_file); goto out; } - ret = btrfs_mksubvol(&file->f_path, vol_args->name, - file->f_path.dentry->d_inode->i_mode, - namelen, BTRFS_I(src_inode)->root); + ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen, + BTRFS_I(src_inode)->root); fput(src_file); } - out: kfree(vol_args); return ret; } +/* + * helper to check if the subvolume references other subvolumes + */ +static noinline int may_destroy_subvol(struct btrfs_root *root) +{ + struct btrfs_path *path; + struct btrfs_key key; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = root->root_key.objectid; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = (u64)-1; + + ret = btrfs_search_slot(NULL, root->fs_info->tree_root, + &key, path, 0, 0); + if (ret < 0) + goto out; + BUG_ON(ret == 0); + + ret = 0; + if (path->slots[0] > 0) { + path->slots[0]--; + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + if (key.objectid == root->root_key.objectid && + key.type == BTRFS_ROOT_REF_KEY) + ret = -ENOTEMPTY; + } +out: + btrfs_free_path(path); + return ret; +} + +static noinline int btrfs_ioctl_snap_destroy(struct file *file, + void __user *arg) +{ + struct dentry *parent = fdentry(file); + struct dentry *dentry; + struct inode *dir = parent->d_inode; + struct inode *inode; + struct btrfs_root *root = BTRFS_I(dir)->root; + struct btrfs_root *dest = NULL; + struct btrfs_ioctl_vol_args *vol_args; + struct btrfs_trans_handle *trans; + int namelen; + int ret; + int err = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) + return PTR_ERR(vol_args); + + vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; + namelen = strlen(vol_args->name); + if (strchr(vol_args->name, '/') || + strncmp(vol_args->name, "..", namelen) == 0) { + err = -EINVAL; + goto out; + } + + err = mnt_want_write(file->f_path.mnt); + if (err) + goto out; + + mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); + dentry = lookup_one_len(vol_args->name, parent, namelen); + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + goto out_unlock_dir; + } + + if (!dentry->d_inode) { + err = -ENOENT; + goto out_dput; + } + + inode = dentry->d_inode; + if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) { + err = -EINVAL; + goto out_dput; + } + + dest = BTRFS_I(inode)->root; + + mutex_lock(&inode->i_mutex); + err = d_invalidate(dentry); + if (err) + goto out_unlock; + + down_write(&root->fs_info->subvol_sem); + + err = may_destroy_subvol(dest); + if (err) + goto out_up_write; + + trans = btrfs_start_transaction(root, 1); + ret = btrfs_unlink_subvol(trans, root, dir, + dest->root_key.objectid, + dentry->d_name.name, + dentry->d_name.len); + BUG_ON(ret); + + btrfs_record_root_in_trans(trans, dest); + + memset(&dest->root_item.drop_progress, 0, + sizeof(dest->root_item.drop_progress)); + dest->root_item.drop_level = 0; + btrfs_set_root_refs(&dest->root_item, 0); + + ret = btrfs_insert_orphan_item(trans, + root->fs_info->tree_root, + dest->root_key.objectid); + BUG_ON(ret); + + ret = btrfs_commit_transaction(trans, root); + BUG_ON(ret); + inode->i_flags |= S_DEAD; +out_up_write: + up_write(&root->fs_info->subvol_sem); +out_unlock: + mutex_unlock(&inode->i_mutex); + if (!err) { + btrfs_invalidate_inodes(dest); + d_delete(dentry); + } +out_dput: + dput(dentry); +out_unlock_dir: + mutex_unlock(&dir->i_mutex); + mnt_drop_write(file->f_path.mnt); +out: + kfree(vol_args); + return err; +} + static int btrfs_ioctl_defrag(struct file *file) { struct inode *inode = fdentry(file)->d_inode; @@ -853,8 +899,8 @@ static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) return ret; } -static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, - u64 off, u64 olen, u64 destoff) +static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, + u64 off, u64 olen, u64 destoff) { struct inode *inode = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; @@ -1246,6 +1292,8 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_ioctl_snap_create(file, argp, 0); case BTRFS_IOC_SUBVOL_CREATE: return btrfs_ioctl_snap_create(file, argp, 1); + case BTRFS_IOC_SNAP_DESTROY: + return btrfs_ioctl_snap_destroy(file, argp); case BTRFS_IOC_DEFRAG: return btrfs_ioctl_defrag(file); case BTRFS_IOC_RESIZE: diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index b320b103fa1..bc49914475e 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -65,5 +65,6 @@ struct btrfs_ioctl_clone_range_args { #define BTRFS_IOC_SUBVOL_CREATE _IOW(BTRFS_IOCTL_MAGIC, 14, \ struct btrfs_ioctl_vol_args) - +#define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \ + struct btrfs_ioctl_vol_args) #endif diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 3be16ccc7ee..48a50426063 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -3203,6 +3203,7 @@ static int check_extent_flags(u64 flags) return 0; } + static noinline_for_stack int relocate_block_group(struct reloc_control *rc) { struct rb_root blocks = RB_ROOT; @@ -3220,6 +3221,9 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc) if (!path) return -ENOMEM; + rc->extents_found = 0; + rc->extents_skipped = 0; + rc->search_start = rc->block_group->key.objectid; clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY, GFP_NOFS); @@ -3475,14 +3479,15 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start) btrfs_wait_ordered_extents(fs_info->tree_root, 0); while (1) { - mutex_lock(&fs_info->cleaner_mutex); - btrfs_clean_old_snapshots(fs_info->tree_root); - mutex_unlock(&fs_info->cleaner_mutex); - rc->extents_found = 0; rc->extents_skipped = 0; + mutex_lock(&fs_info->cleaner_mutex); + + btrfs_clean_old_snapshots(fs_info->tree_root); ret = relocate_block_group(rc); + + mutex_unlock(&fs_info->cleaner_mutex); if (ret < 0) { err = ret; break; @@ -3530,6 +3535,26 @@ out: return err; } +static noinline_for_stack int mark_garbage_root(struct btrfs_root *root) +{ + struct btrfs_trans_handle *trans; + int ret; + + trans = btrfs_start_transaction(root->fs_info->tree_root, 1); + + memset(&root->root_item.drop_progress, 0, + sizeof(root->root_item.drop_progress)); + root->root_item.drop_level = 0; + btrfs_set_root_refs(&root->root_item, 0); + ret = btrfs_update_root(trans, root->fs_info->tree_root, + &root->root_key, &root->root_item); + BUG_ON(ret); + + ret = btrfs_end_transaction(trans, root->fs_info->tree_root); + BUG_ON(ret); + return 0; +} + /* * recover relocation interrupted by system crash. * @@ -3589,8 +3614,12 @@ int btrfs_recover_relocation(struct btrfs_root *root) fs_root = read_fs_root(root->fs_info, reloc_root->root_key.offset); if (IS_ERR(fs_root)) { - err = PTR_ERR(fs_root); - goto out; + ret = PTR_ERR(fs_root); + if (ret != -ENOENT) { + err = ret; + goto out; + } + mark_garbage_root(reloc_root); } } diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c index 5ef72599a58..9351428f30e 100644 --- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -94,17 +94,23 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, goto out; BUG_ON(ret == 0); + if (path->slots[0] == 0) { + ret = 1; + goto out; + } l = path->nodes[0]; - BUG_ON(path->slots[0] == 0); slot = path->slots[0] - 1; btrfs_item_key_to_cpu(l, &found_key, slot); - if (found_key.objectid != objectid) { + if (found_key.objectid != objectid || + found_key.type != BTRFS_ROOT_ITEM_KEY) { ret = 1; goto out; } - read_extent_buffer(l, item, btrfs_item_ptr_offset(l, slot), - sizeof(*item)); - memcpy(key, &found_key, sizeof(found_key)); + if (item) + read_extent_buffer(l, item, btrfs_item_ptr_offset(l, slot), + sizeof(*item)); + if (key) + memcpy(key, &found_key, sizeof(found_key)); ret = 0; out: btrfs_free_path(path); @@ -249,6 +255,59 @@ err: return ret; } +int btrfs_find_orphan_roots(struct btrfs_root *tree_root) +{ + struct extent_buffer *leaf; + struct btrfs_path *path; + struct btrfs_key key; + int err = 0; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = BTRFS_ORPHAN_OBJECTID; + key.type = BTRFS_ORPHAN_ITEM_KEY; + key.offset = 0; + + while (1) { + ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0); + if (ret < 0) { + err = ret; + break; + } + + leaf = path->nodes[0]; + if (path->slots[0] >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(tree_root, path); + if (ret < 0) + err = ret; + if (ret != 0) + break; + leaf = path->nodes[0]; + } + + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + btrfs_release_path(tree_root, path); + + if (key.objectid != BTRFS_ORPHAN_OBJECTID || + key.type != BTRFS_ORPHAN_ITEM_KEY) + break; + + ret = btrfs_find_dead_roots(tree_root, key.offset); + if (ret) { + err = ret; + break; + } + + key.offset++; + } + + btrfs_free_path(path); + return err; +} + /* drop the root item for 'key' from 'root' */ int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_key *key) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 6d6d06cb6df..0242c8babae 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -676,6 +676,7 @@ static int btrfs_unfreeze(struct super_block *sb) } static struct super_operations btrfs_super_ops = { + .drop_inode = btrfs_drop_inode, .delete_inode = btrfs_delete_inode, .put_super = btrfs_put_super, .sync_fs = btrfs_sync_fs, diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 915077725fe..88f866f85e7 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -104,7 +104,6 @@ static noinline int record_root_in_trans(struct btrfs_trans_handle *trans, { if (root->ref_cows && root->last_trans < trans->transid) { WARN_ON(root == root->fs_info->extent_root); - WARN_ON(root->root_item.refs == 0); WARN_ON(root->commit_root != root->node); radix_tree_tag_set(&root->fs_info->fs_roots_radix, @@ -1078,8 +1077,13 @@ int btrfs_clean_old_snapshots(struct btrfs_root *root) while (!list_empty(&list)) { root = list_entry(list.next, struct btrfs_root, root_list); - list_del_init(&root->root_list); - btrfs_drop_snapshot(root, 0); + list_del(&root->root_list); + + if (btrfs_header_backref_rev(root->node) < + BTRFS_MIXED_BACKREF_REV) + btrfs_drop_snapshot(root, 0); + else + btrfs_drop_snapshot(root, 1); } return 0; } diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 6e674d76186..4d7d9abef42 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -2841,7 +2841,7 @@ static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans, if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb) break; - if (parent == sb->s_root) + if (IS_ROOT(parent)) break; parent = parent->d_parent; @@ -2880,6 +2880,12 @@ int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, goto end_no_trans; } + if (root != BTRFS_I(inode)->root || + btrfs_root_refs(&root->root_item) == 0) { + ret = 1; + goto end_no_trans; + } + ret = check_parent_dirs_for_sync(trans, inode, parent, sb, last_committed); if (ret) @@ -2907,12 +2913,15 @@ int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, break; inode = parent->d_inode; + if (root != BTRFS_I(inode)->root) + break; + if (BTRFS_I(inode)->generation > root->fs_info->last_trans_committed) { ret = btrfs_log_inode(trans, root, inode, inode_only); BUG_ON(ret); } - if (parent == sb->s_root) + if (IS_ROOT(parent)) break; parent = parent->d_parent; -- cgit v1.2.3-70-g09d2