diff options
author | Eric Biggers <ebiggers@google.com> | 2019-04-14 17:37:09 -0700 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2019-04-25 15:38:12 +0800 |
commit | 877b5691f27a1aec0d9b53095a323e45c30069e2 (patch) | |
tree | 59eba93e8d253fb0e12a0a2040de99e96e873933 /drivers/md/dm-crypt.c | |
parent | 75f2222832e0fecba7a45ca6ac07ea895ea1e046 (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/dm-crypt.c')
-rw-r--r-- | drivers/md/dm-crypt.c | 3 |
1 files changed, 0 insertions, 3 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); shash_desc_zero(desc); @@ -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) |