linux/fs/crypto
Eric Biggers 877b5691f2 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>
2019-04-25 15:38:12 +08:00
..
bio.c block: allow bio_for_each_segment_all() to iterate over multi-page bvec 2019-02-15 08:40:11 -07:00
crypto.c fscrypt: add Adiantum support 2019-01-06 08:36:21 -05:00
fname.c fscrypt: add Adiantum support 2019-01-06 08:36:21 -05:00
fscrypt_private.h fscrypt: remove filesystem specific build config option 2019-01-23 23:56:43 -05:00
hooks.c fscrypt: return -EXDEV for incompatible rename or link into encrypted dir 2019-01-23 23:56:43 -05:00
Kconfig fscrypt: remove filesystem specific build config option 2019-01-23 23:56:43 -05:00
keyinfo.c crypto: shash - remove shash_desc::flags 2019-04-25 15:38:12 +08:00
Makefile fscrypt: new helper function - fscrypt_file_open() 2017-10-18 19:52:37 -04:00
policy.c fscrypt: return -EXDEV for incompatible rename or link into encrypted dir 2019-01-23 23:56:43 -05:00