diff options
Diffstat (limited to 'fs/btrfs')
-rw-r--r-- | fs/btrfs/btrfs_inode.h | 13 | ||||
-rw-r--r-- | fs/btrfs/file.c | 2 | ||||
-rw-r--r-- | fs/btrfs/inode.c | 191 | ||||
-rw-r--r-- | fs/btrfs/ioctl.c | 32 | ||||
-rw-r--r-- | fs/btrfs/tree-log.c | 63 | ||||
-rw-r--r-- | fs/btrfs/tree-log.h | 2 | ||||
-rw-r--r-- | fs/btrfs/volumes.c | 13 |
7 files changed, 208 insertions, 108 deletions
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 43527fd78825..56b8522d5767 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -234,8 +234,17 @@ static inline int btrfs_inode_in_log(struct inode *inode, u64 generation) BTRFS_I(inode)->last_sub_trans <= BTRFS_I(inode)->last_log_commit && BTRFS_I(inode)->last_sub_trans <= - BTRFS_I(inode)->root->last_log_commit) - return 1; + BTRFS_I(inode)->root->last_log_commit) { + /* + * After a ranged fsync we might have left some extent maps + * (that fall outside the fsync's range). So return false + * here if the list isn't empty, to make sure btrfs_log_inode() + * will be called and process those extent maps. + */ + smp_mb(); + if (list_empty(&BTRFS_I(inode)->extent_tree.modified_extents)) + return 1; + } return 0; } diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 36861b7a6757..ff1cc0399b9a 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1966,7 +1966,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync) btrfs_init_log_ctx(&ctx); - ret = btrfs_log_dentry_safe(trans, root, dentry, &ctx); + ret = btrfs_log_dentry_safe(trans, root, dentry, start, end, &ctx); if (ret < 0) { /* Fallthrough and commit/free transaction. */ ret = 1; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 9c194bd74d6e..016c403bfe7e 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -778,8 +778,12 @@ retry: ins.offset, BTRFS_ORDERED_COMPRESSED, async_extent->compress_type); - if (ret) + if (ret) { + btrfs_drop_extent_cache(inode, async_extent->start, + async_extent->start + + async_extent->ram_size - 1, 0); goto out_free_reserve; + } /* * clear dirty, set writeback and unlock the pages. @@ -971,14 +975,14 @@ static noinline int cow_file_range(struct inode *inode, ret = btrfs_add_ordered_extent(inode, start, ins.objectid, ram_size, cur_alloc_size, 0); if (ret) - goto out_reserve; + goto out_drop_extent_cache; if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) { ret = btrfs_reloc_clone_csums(inode, start, cur_alloc_size); if (ret) - goto out_reserve; + goto out_drop_extent_cache; } if (disk_num_bytes < cur_alloc_size) @@ -1006,6 +1010,8 @@ static noinline int cow_file_range(struct inode *inode, out: return ret; +out_drop_extent_cache: + btrfs_drop_extent_cache(inode, start, start + ram_size - 1, 0); out_reserve: btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1); out_unlock: @@ -4242,7 +4248,8 @@ out: btrfs_abort_transaction(trans, root, ret); } error: - if (last_size != (u64)-1) + if (last_size != (u64)-1 && + root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) btrfs_ordered_update_i_size(inode, last_size, NULL); btrfs_free_path(path); return err; @@ -5627,6 +5634,17 @@ int btrfs_set_inode_index(struct inode *dir, u64 *index) return ret; } +static int btrfs_insert_inode_locked(struct inode *inode) +{ + struct btrfs_iget_args args; + args.location = &BTRFS_I(inode)->location; + args.root = BTRFS_I(inode)->root; + + return insert_inode_locked4(inode, + btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root), + btrfs_find_actor, &args); +} + static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *dir, @@ -5719,10 +5737,19 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, sizes[1] = name_len + sizeof(*ref); } + location = &BTRFS_I(inode)->location; + location->objectid = objectid; + location->offset = 0; + btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY); + + ret = btrfs_insert_inode_locked(inode); + if (ret < 0) + goto fail; + path->leave_spinning = 1; ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems); if (ret != 0) - goto fail; + goto fail_unlock; inode_init_owner(inode, dir, mode); inode_set_bytes(inode, 0); @@ -5745,11 +5772,6 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(path->nodes[0]); btrfs_free_path(path); - location = &BTRFS_I(inode)->location; - location->objectid = objectid; - location->offset = 0; - btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY); - btrfs_inherit_iflags(inode, dir); if (S_ISREG(mode)) { @@ -5760,7 +5782,6 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, BTRFS_INODE_NODATASUM; } - btrfs_insert_inode_hash(inode); inode_tree_add(inode); trace_btrfs_inode_new(inode); @@ -5775,6 +5796,9 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, btrfs_ino(inode), root->root_key.objectid, ret); return inode; + +fail_unlock: + unlock_new_inode(inode); fail: if (dir && name) BTRFS_I(dir)->index_cnt--; @@ -5909,28 +5933,28 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry, goto out_unlock; } - err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); - if (err) { - drop_inode = 1; - goto out_unlock; - } - /* * If the active LSM wants to access the inode during * d_instantiate it needs these. Smack checks to see * if the filesystem supports xattrs by looking at the * ops vector. */ - inode->i_op = &btrfs_special_inode_operations; - err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); + init_special_inode(inode, inode->i_mode, rdev); + + err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); if (err) - drop_inode = 1; - else { - init_special_inode(inode, inode->i_mode, rdev); + goto out_unlock_inode; + + err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); + if (err) { + goto out_unlock_inode; + } else { btrfs_update_inode(trans, root, inode); + unlock_new_inode(inode); d_instantiate(dentry, inode); } + out_unlock: btrfs_end_transaction(trans, root); btrfs_balance_delayed_items(root); @@ -5940,6 +5964,12 @@ out_unlock: iput(inode); } return err; + +out_unlock_inode: + drop_inode = 1; + unlock_new_inode(inode); + goto out_unlock; + } static int btrfs_create(struct inode *dir, struct dentry *dentry, @@ -5974,15 +6004,6 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, goto out_unlock; } drop_inode_on_err = 1; - - err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); - if (err) - goto out_unlock; - - err = btrfs_update_inode(trans, root, inode); - if (err) - goto out_unlock; - /* * If the active LSM wants to access the inode during * d_instantiate it needs these. Smack checks to see @@ -5991,14 +6012,23 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, */ inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; + inode->i_mapping->a_ops = &btrfs_aops; + inode->i_mapping->backing_dev_info = &root->fs_info->bdi; + + err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); + if (err) + goto out_unlock_inode; + + err = btrfs_update_inode(trans, root, inode); + if (err) + goto out_unlock_inode; err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); if (err) - goto out_unlock; + goto out_unlock_inode; - inode->i_mapping->a_ops = &btrfs_aops; - inode->i_mapping->backing_dev_info = &root->fs_info->bdi; BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; + unlock_new_inode(inode); d_instantiate(dentry, inode); out_unlock: @@ -6010,6 +6040,11 @@ out_unlock: btrfs_balance_delayed_items(root); btrfs_btree_balance_dirty(root); return err; + +out_unlock_inode: + unlock_new_inode(inode); + goto out_unlock; + } static int btrfs_link(struct dentry *old_dentry, struct inode *dir, @@ -6117,25 +6152,30 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) } drop_on_err = 1; + /* these must be set before we unlock the inode */ + inode->i_op = &btrfs_dir_inode_operations; + inode->i_fop = &btrfs_dir_file_operations; err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); if (err) - goto out_fail; - - inode->i_op = &btrfs_dir_inode_operations; - inode->i_fop = &btrfs_dir_file_operations; + goto out_fail_inode; btrfs_i_size_write(inode, 0); err = btrfs_update_inode(trans, root, inode); if (err) - goto out_fail; + goto out_fail_inode; err = btrfs_add_link(trans, dir, inode, dentry->d_name.name, dentry->d_name.len, 0, index); if (err) - goto out_fail; + goto out_fail_inode; d_instantiate(dentry, inode); + /* + * mkdir is special. We're unlocking after we call d_instantiate + * to avoid a race with nfsd calling d_instantiate. + */ + unlock_new_inode(inode); drop_on_err = 0; out_fail: @@ -6145,6 +6185,10 @@ out_fail: btrfs_balance_delayed_items(root); btrfs_btree_balance_dirty(root); return err; + +out_fail_inode: + unlock_new_inode(inode); + goto out_fail; } /* helper for btfs_get_extent. Given an existing extent in the tree, @@ -8100,6 +8144,7 @@ int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, set_nlink(inode, 1); btrfs_i_size_write(inode, 0); + unlock_new_inode(inode); err = btrfs_subvol_inherit_props(trans, new_root, parent_root); if (err) @@ -8760,12 +8805,6 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, goto out_unlock; } - err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); - if (err) { - drop_inode = 1; - goto out_unlock; - } - /* * If the active LSM wants to access the inode during * d_instantiate it needs these. Smack checks to see @@ -8774,23 +8813,22 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, */ inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; + inode->i_mapping->a_ops = &btrfs_aops; + inode->i_mapping->backing_dev_info = &root->fs_info->bdi; + BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; + + err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); + if (err) + goto out_unlock_inode; err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); if (err) - drop_inode = 1; - else { - inode->i_mapping->a_ops = &btrfs_aops; - inode->i_mapping->backing_dev_info = &root->fs_info->bdi; - BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; - } - if (drop_inode) - goto out_unlock; + goto out_unlock_inode; path = btrfs_alloc_path(); if (!path) { err = -ENOMEM; - drop_inode = 1; - goto out_unlock; + goto out_unlock_inode; } key.objectid = btrfs_ino(inode); key.offset = 0; @@ -8799,9 +8837,8 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, err = btrfs_insert_empty_item(trans, root, path, &key, datasize); if (err) { - drop_inode = 1; btrfs_free_path(path); - goto out_unlock; + goto out_unlock_inode; } leaf = path->nodes[0]; ei = btrfs_item_ptr(leaf, path->slots[0], @@ -8825,12 +8862,15 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, inode_set_bytes(inode, name_len); btrfs_i_size_write(inode, name_len); err = btrfs_update_inode(trans, root, inode); - if (err) + if (err) { drop_inode = 1; + goto out_unlock_inode; + } + + unlock_new_inode(inode); + d_instantiate(dentry, inode); out_unlock: - if (!err) - d_instantiate(dentry, inode); btrfs_end_transaction(trans, root); if (drop_inode) { inode_dec_link_count(inode); @@ -8838,6 +8878,11 @@ out_unlock: } btrfs_btree_balance_dirty(root); return err; + +out_unlock_inode: + drop_inode = 1; + unlock_new_inode(inode); + goto out_unlock; } static int __btrfs_prealloc_file_range(struct inode *inode, int mode, @@ -9021,14 +9066,6 @@ static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) goto out; } - ret = btrfs_init_inode_security(trans, inode, dir, NULL); - if (ret) - goto out; - - ret = btrfs_update_inode(trans, root, inode); - if (ret) - goto out; - inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; @@ -9036,9 +9073,16 @@ static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) inode->i_mapping->backing_dev_info = &root->fs_info->bdi; BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; + ret = btrfs_init_inode_security(trans, inode, dir, NULL); + if (ret) + goto out_inode; + + ret = btrfs_update_inode(trans, root, inode); + if (ret) + goto out_inode; ret = btrfs_orphan_add(trans, inode); if (ret) - goto out; + goto out_inode; /* * We set number of links to 0 in btrfs_new_inode(), and here we set @@ -9048,6 +9092,7 @@ static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) * d_tmpfile() -> inode_dec_link_count() -> drop_nlink() */ set_nlink(inode, 1); + unlock_new_inode(inode); d_tmpfile(dentry, inode); mark_inode_dirty(inode); @@ -9057,8 +9102,12 @@ out: iput(inode); btrfs_balance_delayed_items(root); btrfs_btree_balance_dirty(root); - return ret; + +out_inode: + unlock_new_inode(inode); + goto out; + } static const struct inode_operations btrfs_dir_inode_operations = { diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index fce6fd0e3f50..8a8e29878c34 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1019,8 +1019,10 @@ static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) return false; next = defrag_lookup_extent(inode, em->start + em->len); - if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE || - (em->block_start + em->block_len == next->block_start)) + if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) + ret = false; + else if ((em->block_start + em->block_len == next->block_start) && + (em->block_len > 128 * 1024 && next->block_len > 128 * 1024)) ret = false; free_extent_map(next); @@ -1055,7 +1057,6 @@ static int should_defrag_range(struct inode *inode, u64 start, int thresh, } next_mergeable = defrag_check_next_extent(inode, em); - /* * we hit a real extent, if it is big or the next extent is not a * real extent, don't bother defragging it @@ -1702,7 +1703,7 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | BTRFS_SUBVOL_QGROUP_INHERIT)) { ret = -EOPNOTSUPP; - goto out; + goto free_args; } if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) @@ -1712,27 +1713,31 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { if (vol_args->size > PAGE_CACHE_SIZE) { ret = -EINVAL; - goto out; + goto free_args; } inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); if (IS_ERR(inherit)) { ret = PTR_ERR(inherit); - goto out; + goto free_args; } } ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, vol_args->fd, subvol, ptr, readonly, inherit); + if (ret) + goto free_inherit; - if (ret == 0 && ptr && - copy_to_user(arg + - offsetof(struct btrfs_ioctl_vol_args_v2, - transid), ptr, sizeof(*ptr))) + if (ptr && copy_to_user(arg + + offsetof(struct btrfs_ioctl_vol_args_v2, + transid), + ptr, sizeof(*ptr))) ret = -EFAULT; -out: - kfree(vol_args); + +free_inherit: kfree(inherit); +free_args: + kfree(vol_args); return ret; } @@ -2652,7 +2657,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) { ret = PTR_ERR(vol_args); - goto out; + goto err_drop; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; @@ -2670,6 +2675,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) out: kfree(vol_args); +err_drop: mnt_drop_write_file(file); return ret; } diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 7e0e6e3029dd..1d1ba083ca6e 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -94,8 +94,10 @@ #define LOG_WALK_REPLAY_ALL 3 static int btrfs_log_inode(struct btrfs_trans_handle *trans, - struct btrfs_root *root, struct inode *inode, - int inode_only); + struct btrfs_root *root, struct inode *inode, + int inode_only, + const loff_t start, + const loff_t end); static int link_to_fixup_dir(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 objectid); @@ -3858,8 +3860,10 @@ process: * This handles both files and directories. */ static int btrfs_log_inode(struct btrfs_trans_handle *trans, - struct btrfs_root *root, struct inode *inode, - int inode_only) + struct btrfs_root *root, struct inode *inode, + int inode_only, + const loff_t start, + const loff_t end) { struct btrfs_path *path; struct btrfs_path *dst_path; @@ -3876,6 +3880,7 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans, int ins_nr; bool fast_search = false; u64 ino = btrfs_ino(inode); + struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; path = btrfs_alloc_path(); if (!path) @@ -4049,13 +4054,35 @@ log_extents: goto out_unlock; } } else if (inode_only == LOG_INODE_ALL) { - struct extent_map_tree *tree = &BTRFS_I(inode)->extent_tree; struct extent_map *em, *n; - write_lock(&tree->lock); - list_for_each_entry_safe(em, n, &tree->modified_extents, list) - list_del_init(&em->list); - write_unlock(&tree->lock); + write_lock(&em_tree->lock); + /* + * We can't just remove every em if we're called for a ranged + * fsync - that is, one that doesn't cover the whole possible + * file range (0 to LLONG_MAX). This is because we can have + * em's that fall outside the range we're logging and therefore + * their ordered operations haven't completed yet + * (btrfs_finish_ordered_io() not invoked yet). This means we + * didn't get their respective file extent item in the fs/subvol + * tree yet, and need to let the next fast fsync (one which + * consults the list of modified extent maps) find the em so + * that it logs a matching file extent item and waits for the + * respective ordered operation to complete (if it's still + * running). + * + * Removing every em outside the range we're logging would make + * the next fast fsync not log their matching file extent items, + * therefore making us lose data after a log replay. + */ + list_for_each_entry_safe(em, n, &em_tree->modified_extents, + list) { + const u64 mod_end = em->mod_start + em->mod_len - 1; + + if (em->mod_start >= start && mod_end <= end) + list_del_init(&em->list); + } + write_unlock(&em_tree->lock); } if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) { @@ -4065,6 +4092,7 @@ log_extents: goto out_unlock; } } + BTRFS_I(inode)->logged_trans = trans->transid; BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->last_sub_trans; out_unlock: @@ -4161,7 +4189,10 @@ out: */ static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, - struct dentry *parent, int exists_only, + struct dentry *parent, + const loff_t start, + const loff_t end, + int exists_only, struct btrfs_log_ctx *ctx) { int inode_only = exists_only ? LOG_INODE_EXISTS : LOG_INODE_ALL; @@ -4207,7 +4238,7 @@ static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, if (ret) goto end_no_trans; - ret = btrfs_log_inode(trans, root, inode, inode_only); + ret = btrfs_log_inode(trans, root, inode, inode_only, start, end); if (ret) goto end_trans; @@ -4235,7 +4266,8 @@ static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, if (BTRFS_I(inode)->generation > root->fs_info->last_trans_committed) { - ret = btrfs_log_inode(trans, root, inode, inode_only); + ret = btrfs_log_inode(trans, root, inode, inode_only, + 0, LLONG_MAX); if (ret) goto end_trans; } @@ -4269,13 +4301,15 @@ end_no_trans: */ int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct dentry *dentry, + const loff_t start, + const loff_t end, struct btrfs_log_ctx *ctx) { struct dentry *parent = dget_parent(dentry); int ret; ret = btrfs_log_inode_parent(trans, root, dentry->d_inode, parent, - 0, ctx); + start, end, 0, ctx); dput(parent); return ret; @@ -4512,6 +4546,7 @@ int btrfs_log_new_name(struct btrfs_trans_handle *trans, root->fs_info->last_trans_committed)) return 0; - return btrfs_log_inode_parent(trans, root, inode, parent, 1, NULL); + return btrfs_log_inode_parent(trans, root, inode, parent, 0, + LLONG_MAX, 1, NULL); } diff --git a/fs/btrfs/tree-log.h b/fs/btrfs/tree-log.h index 7f5b41bd5373..e2e798ae7cd7 100644 --- a/fs/btrfs/tree-log.h +++ b/fs/btrfs/tree-log.h @@ -59,6 +59,8 @@ int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans, int btrfs_recover_log_trees(struct btrfs_root *tree_root); int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct dentry *dentry, + const loff_t start, + const loff_t end, struct btrfs_log_ctx *ctx); int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans, struct btrfs_root *root, diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 340a92d08e84..2c2d6d1d8eee 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -529,12 +529,12 @@ static noinline int device_list_add(const char *path, */ /* - * As of now don't allow update to btrfs_fs_device through - * the btrfs dev scan cli, after FS has been mounted. + * For now, we do allow update to btrfs_fs_device through the + * btrfs dev scan cli after FS has been mounted. We're still + * tracking a problem where systems fail mount by subvolume id + * when we reject replacement on a mounted FS. */ - if (fs_devices->opened) { - return -EBUSY; - } else { + if (!fs_devices->opened && found_transid < device->generation) { /* * That is if the FS is _not_ mounted and if you * are here, that means there is more than one @@ -542,8 +542,7 @@ static noinline int device_list_add(const char *path, * with larger generation number or the last-in if * generation are equal. */ - if (found_transid < device->generation) - return -EEXIST; + return -EEXIST; } name = rcu_string_strdup(path, GFP_NOFS); |