From: Ard Biesheuvel <ardb@kernel.org>
Kernel mode NEON sections are now preemptible on arm64, and so there is
no need to yield it when calling APIs that may sleep.
Also, move the calls to kernel_neon_end() to the same scope as
kernel_neon_begin(). This is needed for a subsequent change where a
stack buffer is allocated transparently and passed to
kernel_neon_begin().
While at it, simplify the logic.
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
arch/arm64/crypto/sm4-ce-gcm-glue.c | 25 +++++---------------
1 file changed, 6 insertions(+), 19 deletions(-)
diff --git a/arch/arm64/crypto/sm4-ce-gcm-glue.c b/arch/arm64/crypto/sm4-ce-gcm-glue.c
index c2ea3d5f690b..8f6fc8c33c3f 100644
--- a/arch/arm64/crypto/sm4-ce-gcm-glue.c
+++ b/arch/arm64/crypto/sm4-ce-gcm-glue.c
@@ -154,36 +154,23 @@ static int gcm_crypt(struct aead_request *req, struct skcipher_walk *walk,
if (req->assoclen)
gcm_calculate_auth_mac(req, ghash);
- while (walk->nbytes) {
+ do {
unsigned int tail = walk->nbytes % SM4_BLOCK_SIZE;
const u8 *src = walk->src.virt.addr;
u8 *dst = walk->dst.virt.addr;
+ const u8 *l = NULL;
if (walk->nbytes == walk->total) {
- sm4_ce_pmull_gcm_crypt(ctx->key.rkey_enc, dst, src, iv,
- walk->nbytes, ghash,
- ctx->ghash_table,
- (const u8 *)&lengths);
-
- kernel_neon_end();
-
- return skcipher_walk_done(walk, 0);
+ l = (const u8 *)&lengths;
+ tail = 0;
}
sm4_ce_pmull_gcm_crypt(ctx->key.rkey_enc, dst, src, iv,
walk->nbytes - tail, ghash,
- ctx->ghash_table, NULL);
-
- kernel_neon_end();
+ ctx->ghash_table, l);
err = skcipher_walk_done(walk, tail);
-
- kernel_neon_begin();
- }
-
- sm4_ce_pmull_gcm_crypt(ctx->key.rkey_enc, NULL, NULL, iv,
- walk->nbytes, ghash, ctx->ghash_table,
- (const u8 *)&lengths);
+ } while (walk->nbytes);
kernel_neon_end();
--
2.51.1.930.gacf6e81ea2-goog