1 // SPDX-License-Identifier: GPL-2.0
31  * has a lot of careful code around i_size and it seems better to make a new key
40  * fs verity items are stored under two different key types on disk.
55  * starting at offset 0 for this key type.  These are also opaque to btrfs,
59  * linearly with the size of the file (with 4K pages/blocks and SHA-256, it's
61  * operation. For that reason, we guard the whole enable verity operation
76  * fs-verity, it is convenient to do size computations in terms of a file
87 	u64 sz = inode->i_size;  in merkle_file_pos()
90 	if (rounded > inode->i_sb->s_maxbytes)  in merkle_file_pos()
91 		return -EFBIG;  in merkle_file_pos()
103  * Before doing a verity enable we cleanup any existing verity items.
104  * This is also used to clean up if a verity enable failed half way through.
111 	struct btrfs_root *root = inode->root;  in drop_verity_items()
113 	struct btrfs_key key;  in drop_verity_items()  local
119 		return -ENOMEM;  in drop_verity_items()
131 		 * isn't from our key type or objectid  in drop_verity_items()
133 		key.objectid = btrfs_ino(inode);  in drop_verity_items()
134 		key.type = key_type;  in drop_verity_items()
135 		key.offset = (u64)-1;  in drop_verity_items()
137 		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);  in drop_verity_items()
141 			if (path->slots[0] == 0)  in drop_verity_items()
143 			path->slots[0]--;  in drop_verity_items()
149 		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);  in drop_verity_items()
152 		if (key.objectid != btrfs_ino(inode) || key.type != key_type)  in drop_verity_items()
161 		ret = btrfs_del_items(trans, root, path, path->slots[0], 1);  in drop_verity_items()
202  * Insert and write inode items with a given key type and offset.
205  * @key_type:  key type to insert
211  * The inserted items will have key (ino, key_type, offset + off) where off is
221 	struct btrfs_root *root = inode->root;  in write_key_bytes()
223 	struct btrfs_key key;  in write_key_bytes()  local
231 		return -ENOMEM;  in write_key_bytes()
241 		key.objectid = btrfs_ino(inode);  in write_key_bytes()
242 		key.type = key_type;  in write_key_bytes()
243 		key.offset = offset;  in write_key_bytes()
251 		ret = btrfs_insert_empty_item(trans, root, path, &key, copy_bytes);  in write_key_bytes()
257 		leaf = path->nodes[0];  in write_key_bytes()
259 		data = btrfs_item_ptr(leaf, path->slots[0], void);  in write_key_bytes()
264 		len -= copy_bytes;  in write_key_bytes()
275  * Read inode items of the given key type and offset from the btree.
278  * @key_type:   key type to read
284  *              page and ignore dest, but it must still be non-NULL to avoid the
285  *              counting-only behavior.
300 	struct btrfs_root *root = inode->root;  in read_key_bytes()
302 	struct btrfs_key key;  in read_key_bytes()  local
315 		return -ENOMEM;  in read_key_bytes()
318 		path->reada = READA_FORWARD;  in read_key_bytes()
320 	key.objectid = btrfs_ino(inode);  in read_key_bytes()
321 	key.type = key_type;  in read_key_bytes()
322 	key.offset = offset;  in read_key_bytes()
324 	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);  in read_key_bytes()
329 		if (path->slots[0] == 0)  in read_key_bytes()
331 		path->slots[0]--;  in read_key_bytes()
335 		leaf = path->nodes[0];  in read_key_bytes()
336 		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);  in read_key_bytes()
338 		if (key.objectid != btrfs_ino(inode) || key.type != key_type)  in read_key_bytes()
341 		item_end = btrfs_item_size(leaf, path->slots[0]) + key.offset;  in read_key_bytes()
348 			if (key.offset != offset)  in read_key_bytes()
355 			if (key.offset > offset)  in read_key_bytes()
368 		copy_bytes = copy_end - offset;  in read_key_bytes()
371 		copy_offset = offset - key.offset;  in read_key_bytes()
377 			data = btrfs_item_ptr(leaf, path->slots[0], void);  in read_key_bytes()
388 		len -= copy_bytes;  in read_key_bytes()
391 		path->slots[0]++;  in read_key_bytes()
392 		if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {  in read_key_bytes()
427 	struct btrfs_root *root = inode->root;  in del_orphan()
437 	if (!inode->vfs_inode.i_nlink)  in del_orphan()
441 	if (ret == -ENOENT)  in del_orphan()
447  * Rollback in-progress verity if we encounter an error.
460 	struct btrfs_root *root = inode->root;  in rollback_verity()
464 	truncate_inode_pages(inode->vfs_inode.i_mapping, inode->vfs_inode.i_size);  in rollback_verity()
465 	clear_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags);  in rollback_verity()
468 		btrfs_handle_fs_error(root->fs_info, ret,  in rollback_verity()
470 				(u64)inode->vfs_inode.i_ino);  in rollback_verity()
482 		btrfs_handle_fs_error(root->fs_info, ret,  in rollback_verity()
484 			(u64)inode->vfs_inode.i_ino);  in rollback_verity()
487 	inode->ro_flags &= ~BTRFS_INODE_RO_VERITY;  in rollback_verity()
488 	btrfs_sync_inode_flags_to_i_flags(&inode->vfs_inode);  in rollback_verity()
515  * - write out the descriptor items
516  * - mark the inode with the verity flag
517  * - delete the orphan item
518  * - mark the ro compat bit
519  * - clear the in progress bit
527 	struct btrfs_root *root = inode->root;  in finish_verity()
554 	inode->ro_flags |= BTRFS_INODE_RO_VERITY;  in finish_verity()
555 	btrfs_sync_inode_flags_to_i_flags(&inode->vfs_inode);  in finish_verity()
562 	clear_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags);  in finish_verity()
563 	btrfs_set_fs_compat_ro(root->fs_info, VERITY);  in finish_verity()
574  * @filp:  file to enable verity on
584 	struct btrfs_root *root = inode->root;  in btrfs_begin_enable_verity()
590 	if (test_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags))  in btrfs_begin_enable_verity()
591 		return -EBUSY;  in btrfs_begin_enable_verity()
595 	 * possible that we failed to enable verity on a file, then were  in btrfs_begin_enable_verity()
597 	 * orphan, and finally attempt to enable verity again.  in btrfs_begin_enable_verity()
610 		set_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags);  in btrfs_begin_enable_verity()
625  * enable, and we should try to rollback. Otherwise, attempt to finish verity.
649 		btrfs_err(inode->root->fs_info,  in btrfs_end_enable_verity()
680 		return -EUCLEAN;  in btrfs_get_verity_descriptor()
684 		return -EUCLEAN;  in btrfs_get_verity_descriptor()
689 		return -ERANGE;  in btrfs_get_verity_descriptor()
696 		return -EIO;  in btrfs_get_verity_descriptor()
724 	if (merkle_pos > inode->i_sb->s_maxbytes - off - PAGE_SIZE)  in btrfs_read_merkle_tree_page()
725 		return ERR_PTR(-EFBIG);  in btrfs_read_merkle_tree_page()
728 	folio = __filemap_get_folio(inode->i_mapping, index, FGP_ACCESSED, 0);  in btrfs_read_merkle_tree_page()
738 			return ERR_PTR(-EIO);  in btrfs_read_merkle_tree_page()
744 	folio = filemap_alloc_folio(mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS),  in btrfs_read_merkle_tree_page()
747 		return ERR_PTR(-ENOMEM);  in btrfs_read_merkle_tree_page()
749 	ret = filemap_add_folio(inode->i_mapping, folio, index, GFP_NOFS);  in btrfs_read_merkle_tree_page()
753 		if (ret == -EEXIST)  in btrfs_read_merkle_tree_page()
797 	if (merkle_pos > inode->i_sb->s_maxbytes - pos - size)  in btrfs_write_merkle_tree_block()
798 		return -EFBIG;  in btrfs_write_merkle_tree_block()