linux/arch/x86/power
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
..
cpu.c Merge branch 'WIP.x86-pti.entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-12-18 08:59:15 -08:00
hibernate_32.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
hibernate_64.c x86, hibernate: Rename temp_level4_pgt to temp_pgt 2018-10-03 11:56:34 +02:00
hibernate_asm_32.S x86-32, hibernate: Adjust in_suspend after resumed on 32bit system 2018-10-03 11:56:34 +02:00
hibernate_asm_64.S x86, hibernate: Rename temp_level4_pgt to temp_pgt 2018-10-03 11:56:34 +02:00
hibernate.c crypto: shash - remove shash_desc::flags 2019-04-25 15:38:12 +08:00
Makefile x86, hibernate: Extract the common code of 64/32 bit system 2018-10-03 11:56:33 +02:00