1 // SPDX-License-Identifier: GPL-2.0
16 #include "disk-io.h"
26  * has a lot of careful code around i_size and it seems better to make a new key
35  * fs verity items are stored under two different key types on disk.
43  * the higher level verity code.  The most common descriptor size is 256 bytes.
50  * starting at offset 0 for this key type.  These are also opaque to btrfs,
54  * linearly with the size of the file (with 4K pages/blocks and SHA-256, it's
71  * fs-verity, it is convenient to do size computations in terms of a file
78  * Returns the file offset on success, negative error code on failure.
82 	u64 sz = inode->i_size;  in merkle_file_pos()
85 	if (rounded > inode->i_sb->s_maxbytes)  in merkle_file_pos()
86 		return -EFBIG;  in merkle_file_pos()
101  * Returns number of dropped items on success, negative error code on failure.
106 	struct btrfs_root *root = inode->root;  in drop_verity_items()
108 	struct btrfs_key key;  in drop_verity_items()  local
114 		return -ENOMEM;  in drop_verity_items()
126 		 * isn't from our key type or objectid  in drop_verity_items()
128 		key.objectid = btrfs_ino(inode);  in drop_verity_items()
129 		key.type = key_type;  in drop_verity_items()
130 		key.offset = (u64)-1;  in drop_verity_items()
132 		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);  in drop_verity_items()
136 			if (path->slots[0] == 0)  in drop_verity_items()
138 			path->slots[0]--;  in drop_verity_items()
144 		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);  in drop_verity_items()
147 		if (key.objectid != btrfs_ino(inode) || key.type != key_type)  in drop_verity_items()
156 		ret = btrfs_del_items(trans, root, path, path->slots[0], 1);  in drop_verity_items()
180  * Returns: 0 on success, negative error code on failure.
197  * Insert and write inode items with a given key type and offset.
200  * @key_type:  key type to insert
206  * The inserted items will have key (ino, key_type, offset + off) where off is
209  * Returns 0 on success and a negative error code on failure.
216 	struct btrfs_root *root = inode->root;  in write_key_bytes()
218 	struct btrfs_key key;  in write_key_bytes()  local
226 		return -ENOMEM;  in write_key_bytes()
236 		key.objectid = btrfs_ino(inode);  in write_key_bytes()
237 		key.type = key_type;  in write_key_bytes()
238 		key.offset = offset;  in write_key_bytes()
246 		ret = btrfs_insert_empty_item(trans, root, path, &key, copy_bytes);  in write_key_bytes()
252 		leaf = path->nodes[0];  in write_key_bytes()
254 		data = btrfs_item_ptr(leaf, path->slots[0], void);  in write_key_bytes()
259 		len -= copy_bytes;  in write_key_bytes()
270  * Read inode items of the given key type and offset from the btree.
273  * @key_type:   key type to read
279  *              page and ignore dest, but it must still be non-NULL to avoid the
280  *              counting-only behavior.
289  * Returns number of bytes read or a negative error code on failure.
295 	struct btrfs_root *root = inode->root;  in read_key_bytes()
297 	struct btrfs_key key;  in read_key_bytes()  local
310 		return -ENOMEM;  in read_key_bytes()
313 		path->reada = READA_FORWARD;  in read_key_bytes()
315 	key.objectid = btrfs_ino(inode);  in read_key_bytes()
316 	key.type = key_type;  in read_key_bytes()
317 	key.offset = offset;  in read_key_bytes()
319 	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);  in read_key_bytes()
324 		if (path->slots[0] == 0)  in read_key_bytes()
326 		path->slots[0]--;  in read_key_bytes()
330 		leaf = path->nodes[0];  in read_key_bytes()
331 		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);  in read_key_bytes()
333 		if (key.objectid != btrfs_ino(inode) || key.type != key_type)  in read_key_bytes()
336 		item_end = btrfs_item_size_nr(leaf, path->slots[0]) + key.offset;  in read_key_bytes()
343 			if (key.offset != offset)  in read_key_bytes()
350 			if (key.offset > offset)  in read_key_bytes()
363 		copy_bytes = copy_end - offset;  in read_key_bytes()
366 		copy_offset = offset - key.offset;  in read_key_bytes()
372 			data = btrfs_item_ptr(leaf, path->slots[0], void);  in read_key_bytes()
383 		len -= copy_bytes;  in read_key_bytes()
386 		path->slots[0]++;  in read_key_bytes()
387 		if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {  in read_key_bytes()
418  * Returns zero on success or a negative error code on failure.
422 	struct btrfs_root *root = inode->root;  in del_orphan()
432 	if (!inode->vfs_inode.i_nlink)  in del_orphan()
436 	if (ret == -ENOENT)  in del_orphan()
442  * Rollback in-progress verity if we encounter an error.
450  * Returns 0 on success, negative error code on failure.
455 	struct btrfs_root *root = inode->root;  in rollback_verity()
458 	ASSERT(inode_is_locked(&inode->vfs_inode));  in rollback_verity()
459 	truncate_inode_pages(inode->vfs_inode.i_mapping, inode->vfs_inode.i_size);  in rollback_verity()
460 	clear_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags);  in rollback_verity()
463 		btrfs_handle_fs_error(root->fs_info, ret,  in rollback_verity()
465 				(u64)inode->vfs_inode.i_ino);  in rollback_verity()
477 		btrfs_handle_fs_error(root->fs_info, ret,  in rollback_verity()
479 			(u64)inode->vfs_inode.i_ino);  in rollback_verity()
482 	inode->ro_flags &= ~BTRFS_INODE_RO_VERITY;  in rollback_verity()
483 	btrfs_sync_inode_flags_to_i_flags(&inode->vfs_inode);  in rollback_verity()
510  * - write out the descriptor items
511  * - mark the inode with the verity flag
512  * - delete the orphan item
513  * - mark the ro compat bit
514  * - clear the in progress bit
516  * Returns 0 on success, negative error code on failure.
522 	struct btrfs_root *root = inode->root;  in finish_verity()
549 	inode->ro_flags |= BTRFS_INODE_RO_VERITY;  in finish_verity()
550 	btrfs_sync_inode_flags_to_i_flags(&inode->vfs_inode);  in finish_verity()
557 	clear_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags);  in finish_verity()
558 	btrfs_set_fs_compat_ro(root->fs_info, VERITY);  in finish_verity()
574  * Returns 0 on success, negative error code on failure.
579 	struct btrfs_root *root = inode->root;  in btrfs_begin_enable_verity()
585 	if (test_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags))  in btrfs_begin_enable_verity()
586 		return -EBUSY;  in btrfs_begin_enable_verity()
605 		set_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags);  in btrfs_begin_enable_verity()
622  * Returns 0 on success, negative error code on error.
644 		btrfs_err(inode->root->fs_info,  in btrfs_end_enable_verity()
660  * Returns the size on success or a negative error code on failure.
676 		return -EUCLEAN;  in btrfs_get_verity_descriptor()
680 		return -EUCLEAN;  in btrfs_get_verity_descriptor()
685 		return -ERANGE;  in btrfs_get_verity_descriptor()
692 		return -EIO;  in btrfs_get_verity_descriptor()
720 	if (merkle_pos > inode->i_sb->s_maxbytes - off - PAGE_SIZE)  in btrfs_read_merkle_tree_page()
721 		return ERR_PTR(-EFBIG);  in btrfs_read_merkle_tree_page()
724 	page = find_get_page_flags(inode->i_mapping, index, FGP_ACCESSED);  in btrfs_read_merkle_tree_page()
737 			return ERR_PTR(-EIO);  in btrfs_read_merkle_tree_page()
743 	page = __page_cache_alloc(mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));  in btrfs_read_merkle_tree_page()
745 		return ERR_PTR(-ENOMEM);  in btrfs_read_merkle_tree_page()
760 		memzero_page(page, ret, PAGE_SIZE - ret);  in btrfs_read_merkle_tree_page()
763 	ret = add_to_page_cache_lru(page, inode->i_mapping, index, GFP_NOFS);  in btrfs_read_merkle_tree_page()
771 		if (ret == -EEXIST)  in btrfs_read_merkle_tree_page()
789  * Returns 0 on success or negative error code on failure
800 	if (merkle_pos > inode->i_sb->s_maxbytes - off - len)  in btrfs_write_merkle_tree_block()
801 		return -EFBIG;  in btrfs_write_merkle_tree_block()