diff options
| -rw-r--r-- | fs/verity/enable.c | 45 |
1 files changed, 39 insertions, 6 deletions
diff --git a/fs/verity/enable.c b/fs/verity/enable.c index b79e3fd19d11..9c93c17f1c1c 100644 --- a/fs/verity/enable.c +++ b/fs/verity/enable.c @@ -13,13 +13,42 @@ #include <linux/sched/signal.h> #include <linux/uaccess.h> -static int build_merkle_tree_level(struct inode *inode, unsigned int level, +/* + * Read a file data page for Merkle tree construction. Do aggressive readahead, + * since we're sequentially reading the entire file. + */ +static struct page *read_file_data_page(struct file *filp, pgoff_t index, + struct file_ra_state *ra, + unsigned long remaining_pages) +{ + struct page *page; + + page = find_get_page_flags(filp->f_mapping, index, FGP_ACCESSED); + if (!page || !PageUptodate(page)) { + if (page) + put_page(page); + else + page_cache_sync_readahead(filp->f_mapping, ra, filp, + index, remaining_pages); + page = read_mapping_page(filp->f_mapping, index, NULL); + if (IS_ERR(page)) + return page; + } + if (PageReadahead(page)) + page_cache_async_readahead(filp->f_mapping, ra, filp, page, + index, remaining_pages); + return page; +} + +static int build_merkle_tree_level(struct file *filp, unsigned int level, u64 num_blocks_to_hash, const struct merkle_tree_params *params, u8 *pending_hashes, struct ahash_request *req) { + struct inode *inode = file_inode(filp); const struct fsverity_operations *vops = inode->i_sb->s_vop; + struct file_ra_state ra = { 0 }; unsigned int pending_size = 0; u64 dst_block_num; u64 i; @@ -36,6 +65,8 @@ static int build_merkle_tree_level(struct inode *inode, unsigned int level, dst_block_num = 0; /* unused */ } + file_ra_state_init(&ra, filp->f_mapping); + for (i = 0; i < num_blocks_to_hash; i++) { struct page *src_page; @@ -45,7 +76,8 @@ static int build_merkle_tree_level(struct inode *inode, unsigned int level, if (level == 0) { /* Leaf: hashing a data block */ - src_page = read_mapping_page(inode->i_mapping, i, NULL); + src_page = read_file_data_page(filp, i, &ra, + num_blocks_to_hash - i); if (IS_ERR(src_page)) { err = PTR_ERR(src_page); fsverity_err(inode, @@ -103,17 +135,18 @@ static int build_merkle_tree_level(struct inode *inode, unsigned int level, } /* - * Build the Merkle tree for the given inode using the given parameters, and + * Build the Merkle tree for the given file using the given parameters, and * return the root hash in @root_hash. * * The tree is written to a filesystem-specific location as determined by the * ->write_merkle_tree_block() method. However, the blocks that comprise the * tree are the same for all filesystems. */ -static int build_merkle_tree(struct inode *inode, +static int build_merkle_tree(struct file *filp, const struct merkle_tree_params *params, u8 *root_hash) { + struct inode *inode = file_inode(filp); u8 *pending_hashes; struct ahash_request *req; u64 blocks; @@ -139,7 +172,7 @@ static int build_merkle_tree(struct inode *inode, blocks = (inode->i_size + params->block_size - 1) >> params->log_blocksize; for (level = 0; level <= params->num_levels; level++) { - err = build_merkle_tree_level(inode, level, blocks, params, + err = build_merkle_tree_level(filp, level, blocks, params, pending_hashes, req); if (err) goto out; @@ -227,7 +260,7 @@ static int enable_verity(struct file *filp, */ pr_debug("Building Merkle tree...\n"); BUILD_BUG_ON(sizeof(desc->root_hash) < FS_VERITY_MAX_DIGEST_SIZE); - err = build_merkle_tree(inode, ¶ms, desc->root_hash); + err = build_merkle_tree(filp, ¶ms, desc->root_hash); if (err) { fsverity_err(inode, "Error %d building Merkle tree", err); goto rollback; |