path: root/drivers/md
diff options
authorEric Biggers <ebiggers@google.com>2019-04-14 17:37:09 -0700
committerHerbert Xu <herbert@gondor.apana.org.au>2019-04-25 15:38:12 +0800
commit877b5691f27a1aec0d9b53095a323e45c30069e2 (patch)
tree59eba93e8d253fb0e12a0a2040de99e96e873933 /drivers/md
parent75f2222832e0fecba7a45ca6ac07ea895ea1e046 (diff)
crypto: shash - remove shash_desc::flags
The flags field in 'struct shash_desc' never actually does anything. The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP. However, no shash algorithm ever sleeps, making this flag a no-op. With this being the case, inevitably some users who can't sleep wrongly pass MAY_SLEEP. These would all need to be fixed if any shash algorithm actually started sleeping. For example, the shash_ahash_*() functions, which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP from the ahash API to the shash API. However, the shash functions are called under kmap_atomic(), so actually they're assumed to never sleep. Even if it turns out that some users do need preemption points while hashing large buffers, we could easily provide a helper function crypto_shash_update_large() which divides the data into smaller chunks and calls crypto_shash_update() and cond_resched() for each chunk. It's not necessary to have a flag in 'struct shash_desc', nor is it necessary to make individual shash algorithms aware of this at all. Therefore, remove shash_desc::flags, and document that the crypto_shash_*() functions can be called from any context. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/md')
2 files changed, 0 insertions, 5 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index dd6565798778..9faed1c92b52 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -332,7 +332,6 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
int err;
desc->tfm = essiv->hash_tfm;
- desc->flags = 0;
err = crypto_shash_digest(desc, cc->key, cc->key_size, essiv->salt);
@@ -606,7 +605,6 @@ static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
int i, r;
desc->tfm = lmk->hash_tfm;
- desc->flags = 0;
r = crypto_shash_init(desc);
if (r)
@@ -768,7 +766,6 @@ static int crypt_iv_tcw_whitening(struct crypt_config *cc,
/* calculate crc32 for every 32bit part and xor it */
desc->tfm = tcw->crc32_tfm;
- desc->flags = 0;
for (i = 0; i < 4; i++) {
r = crypto_shash_init(desc);
if (r)
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index d57d997a52c8..1366d886907c 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -532,7 +532,6 @@ static void section_mac(struct dm_integrity_c *ic, unsigned section, __u8 result
unsigned j, size;
desc->tfm = ic->journal_mac;
- desc->flags = 0;
r = crypto_shash_init(desc);
if (unlikely(r)) {
@@ -1278,7 +1277,6 @@ static void integrity_sector_checksum(struct dm_integrity_c *ic, sector_t sector
unsigned digest_size;
req->tfm = ic->internal_hash;
- req->flags = 0;
r = crypto_shash_init(req);
if (unlikely(r < 0)) {