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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/crypto/ccp | |
parent | 75f2222832e0fecba7a45ca6ac07ea895ea1e046 (diff) | |
download | linux-877b5691f27a1aec0d9b53095a323e45c30069e2.tar.gz linux-877b5691f27a1aec0d9b53095a323e45c30069e2.tar.bz2 linux-877b5691f27a1aec0d9b53095a323e45c30069e2.zip |
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/crypto/ccp')
-rw-r--r-- | drivers/crypto/ccp/ccp-crypto-sha.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/drivers/crypto/ccp/ccp-crypto-sha.c b/drivers/crypto/ccp/ccp-crypto-sha.c index 10a61cd54fce..3e10573f589e 100644 --- a/drivers/crypto/ccp/ccp-crypto-sha.c +++ b/drivers/crypto/ccp/ccp-crypto-sha.c @@ -293,8 +293,6 @@ static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key, if (key_len > block_size) { /* Must hash the input key */ sdesc->tfm = shash; - sdesc->flags = crypto_ahash_get_flags(tfm) & - CRYPTO_TFM_REQ_MAY_SLEEP; ret = crypto_shash_digest(sdesc, key, key_len, ctx->u.sha.key); |