From b4e967be431cf37f56cd1993592943007d7ab03b Mon Sep 17 00:00:00 2001 From: David Sterba Date: Tue, 8 Oct 2019 18:41:33 +0200 Subject: [PATCH] btrfs: add member for a specific checksum driver Currently all the checksum algorithms generate a fixed size digest size and we use it. The on-disk format can hold up to BTRFS_CSUM_SIZE bytes and BLAKE2b produces digest of 512 bits by default. We can't do that and will use the blake2b-256, this needs to be passed to the crypto API. Separate that from the base algorithm name and add a member to request specific driver, in this case with the digest size. The only place that uses the driver name is the crypto API setup. Signed-off-by: David Sterba --- fs/btrfs/ctree.c | 12 ++++++++++++ fs/btrfs/ctree.h | 1 + fs/btrfs/disk-io.c | 6 +++--- 3 files changed, 16 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index c1561097e5a3..c211216b4524 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -32,6 +32,7 @@ static void del_ptr(struct btrfs_root *root, struct btrfs_path *path, static const struct btrfs_csums { u16 size; const char *name; + const char *driver; } btrfs_csums[] = { [BTRFS_CSUM_TYPE_CRC32] = { .size = 4, .name = "crc32c" }, [BTRFS_CSUM_TYPE_XXHASH] = { .size = 8, .name = "xxhash64" }, @@ -53,6 +54,17 @@ const char *btrfs_super_csum_name(u16 csum_type) return btrfs_csums[csum_type].name; } +/* + * Return driver name if defined, otherwise the name that's also a valid driver + * name + */ +const char *btrfs_super_csum_driver(u16 csum_type) +{ + /* csum type is validated at mount time */ + return btrfs_csums[csum_type].driver ?: + btrfs_csums[csum_type].name; +} + size_t __const btrfs_get_num_csums(void) { return ARRAY_SIZE(btrfs_csums); diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index b17944995e09..4a842c0fa062 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2163,6 +2163,7 @@ BTRFS_SETGET_STACK_FUNCS(super_uuid_tree_generation, struct btrfs_super_block, int btrfs_super_csum_size(const struct btrfs_super_block *s); const char *btrfs_super_csum_name(u16 csum_type); +const char *btrfs_super_csum_driver(u16 csum_type); size_t __const btrfs_get_num_csums(void); diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 21fab336f8ca..948ed5ac0794 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -2219,13 +2219,13 @@ static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info, static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type) { struct crypto_shash *csum_shash; - const char *csum_name = btrfs_super_csum_name(csum_type); + const char *csum_driver = btrfs_super_csum_driver(csum_type); - csum_shash = crypto_alloc_shash(csum_name, 0, 0); + csum_shash = crypto_alloc_shash(csum_driver, 0, 0); if (IS_ERR(csum_shash)) { btrfs_err(fs_info, "error allocating %s hash for checksum", - csum_name); + csum_driver); return PTR_ERR(csum_shash); }