From 877b5691f27a1aec0d9b53095a323e45c30069e2 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 14 Apr 2019 17:37:09 -0700 Subject: 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 Signed-off-by: Herbert Xu --- drivers/crypto/vmx/ghash.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/crypto/vmx') diff --git a/drivers/crypto/vmx/ghash.c b/drivers/crypto/vmx/ghash.c index 611ff591410e..b5a6883bb09e 100644 --- a/drivers/crypto/vmx/ghash.c +++ b/drivers/crypto/vmx/ghash.c @@ -101,7 +101,6 @@ static int p8_ghash_init(struct shash_desc *desc) dctx->bytes = 0; memset(dctx->shash, 0, GHASH_DIGEST_SIZE); dctx->fallback_desc.tfm = ctx->fallback; - dctx->fallback_desc.flags = desc->flags; return crypto_shash_init(&dctx->fallback_desc); } -- cgit v1.2.3