mirror of https://gitee.com/openkylin/linux.git
877b5691f2
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> |
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.. | ||
api-aead.rst | ||
api-akcipher.rst | ||
api-digest.rst | ||
api-intro.txt | ||
api-kpp.rst | ||
api-rng.rst | ||
api-samples.rst | ||
api-skcipher.rst | ||
api.rst | ||
architecture.rst | ||
asymmetric-keys.txt | ||
async-tx-api.txt | ||
conf.py | ||
crypto_engine.rst | ||
descore-readme.txt | ||
devel-algos.rst | ||
index.rst | ||
intro.rst | ||
userspace-if.rst |