s390/crypto: simplify return code handling

The CPACF instructions can complete with three different condition codes:
CC=0 for successful completion, CC=1 if the protected key verification
failed, and CC=3 for partial completion.

The inline functions will restart the CPACF instruction for partial
completion, this removes the CC=3 case. The CC=1 case is only relevant
for the protected key functions of the KM, KMC, KMAC and KMCTR
instructions. As the protected key functions are not used by the
current code, there is no need for any kind of return code handling.

Reviewed-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 7 insertions, 16 deletions

diff --git a/arch/s390/crypto/sha_common.c b/arch/s390/crypto/sha_common.c
index 8e908166c3ee..c740f77285b2 100644
--- a/arch/s390/crypto/sha_common.c
+++ b/arch/s390/crypto/sha_common.c
@@ -22,8 +22,7 @@ int s390_sha_update(struct shash_desc *desc, const u8 *data, unsigned int len)
 {
 	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
 	unsigned int bsize = crypto_shash_blocksize(desc->tfm);
-	unsigned int index;
-	int ret;
+	unsigned int index, n;
 
 	/* how much is already in the buffer? */
 	index = ctx->count & (bsize - 1);
@@ -35,9 +34,7 @@ int s390_sha_update(struct shash_desc *desc, const u8 *data, unsigned int len)
 	/* process one stored block */
 	if (index) {
 		memcpy(ctx->buf + index, data, bsize - index);
-		ret = cpacf_kimd(ctx->func, ctx->state, ctx->buf, bsize);
-		if (ret != bsize)
-			return -EIO;
+		cpacf_kimd(ctx->func, ctx->state, ctx->buf, bsize);
 		data += bsize - index;
 		len -= bsize - index;
 		index = 0;
@@ -45,12 +42,10 @@ int s390_sha_update(struct shash_desc *desc, const u8 *data, unsigned int len)
 
 	/* process as many blocks as possible */
 	if (len >= bsize) {
-		ret = cpacf_kimd(ctx->func, ctx->state, data,
-				 len & ~(bsize - 1));
-		if (ret != (len & ~(bsize - 1)))
-			return -EIO;
-		data += ret;
-		len -= ret;
+		n = len & ~(bsize - 1);
+		cpacf_kimd(ctx->func, ctx->state, data, n);
+		data += n;
+		len -= n;
 	}
 store:
 	if (len)
@@ -66,7 +61,6 @@ int s390_sha_final(struct shash_desc *desc, u8 *out)
 	unsigned int bsize = crypto_shash_blocksize(desc->tfm);
 	u64 bits;
 	unsigned int index, end, plen;
-	int ret;
 
 	/* SHA-512 uses 128 bit padding length */
 	plen = (bsize > SHA256_BLOCK_SIZE) ? 16 : 8;
@@ -88,10 +82,7 @@ int s390_sha_final(struct shash_desc *desc, u8 *out)
 	 */
 	bits = ctx->count * 8;
 	memcpy(ctx->buf + end - 8, &bits, sizeof(bits));
-
-	ret = cpacf_kimd(ctx->func, ctx->state, ctx->buf, end);
-	if (ret != end)
-		return -EIO;
+	cpacf_kimd(ctx->func, ctx->state, ctx->buf, end);
 
 	/* copy digest to out */
 	memcpy(out, ctx->state, crypto_shash_digestsize(desc->tfm));