[PATCH v2 06/21] crypto: hifn_795x: Make use of the new sg_map helper function

Logan Gunthorpe
2017-04-25T18:21:28Z

Conversion of a couple kmap_atomic instances to the sg_map helper
function.

However, it looks like there was a bug in the original code: the source
scatter lists offset (t->offset) was passed to ablkcipher_get which
added it to the destination address. This doesn't make a lot of
sense, but t->offset is likely always zero anyway. So, this patch cleans
that brokeness up.

Also, a change to the error path: if ablkcipher_get failed, everything
seemed to proceed as if it hadn't. Setting 'error' should hopefully
clear that up.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
---
drivers/crypto/hifn_795x.c | 32 +++++++++++++++++++++-----------
1 file changed, 21 insertions(+), 11 deletions(-)

diff --git a/drivers/crypto/hifn_795x.c b/drivers/crypto/hifn_795x.c
index e09d405..34b1870 100644
--- a/drivers/crypto/hifn_795x.c
+++ b/drivers/crypto/hifn_795x.c
@@ -1619,7 +1619,7 @@ static int hifn_start_device(struct hifn_device *dev)
return 0;
}

-static int ablkcipher_get(void *saddr, unsigned int *srestp, unsigned int offset,
+static int ablkcipher_get(void *saddr, unsigned int *srestp,
struct scatterlist *dst, unsigned int size, unsigned int *nbytesp)
{
unsigned int srest = *srestp, nbytes = *nbytesp, copy;
@@ -1632,15 +1632,17 @@ static int ablkcipher_get(void *saddr, unsigned int *srestp, unsigned int offset
while (size) {
copy = min3(srest, dst->length, size);

- daddr = kmap_atomic(sg_page(dst));
- memcpy(daddr + dst->offset + offset, saddr, copy);
- kunmap_atomic(daddr);
+ daddr = sg_map(dst, 0, SG_KMAP_ATOMIC);
+ if (IS_ERR(daddr))
+ return PTR_ERR(daddr);
+
+ memcpy(daddr, saddr, copy);
+ sg_unmap(dst, daddr, 0, SG_KMAP_ATOMIC);

nbytes -= copy;
size -= copy;
srest -= copy;
saddr += copy;
- offset = 0;

pr_debug("%s: copy: %u, size: %u, srest: %u, nbytes: %u.\n",
__func__, copy, size, srest, nbytes);
@@ -1671,11 +1673,12 @@ static inline void hifn_complete_sa(struct hifn_device *dev, int i)

static void hifn_process_ready(struct ablkcipher_request *req, int error)
{
+ int err;
struct hifn_request_context *rctx = ablkcipher_request_ctx(req);

if (rctx->walk.flags & ASYNC_FLAGS_MISALIGNED) {
unsigned int nbytes = req->nbytes;
- int idx = 0, err;
+ int idx = 0;
struct scatterlist *dst, *t;
void *saddr;

@@ -1695,17 +1698,24 @@ static void hifn_process_ready(struct ablkcipher_request *req, int error)
continue;
}

- saddr = kmap_atomic(sg_page(t));
+ saddr = sg_map(t, 0, SG_KMAP_ATOMIC);
+ if (IS_ERR(saddr)) {
+ if (!error)
+ error = PTR_ERR(saddr);
+ break;
+ }
+
+ err = ablkcipher_get(saddr, &t->length,
+ dst, nbytes, &nbytes);
+ sg_unmap(t, saddr, 0, SG_KMAP_ATOMIC);

- err = ablkcipher_get(saddr, &t->length, t->offset,
- dst, nbytes, &nbytes);
if (err < 0) {
- kunmap_atomic(saddr);
+ if (!error)
+ error = err;
break;
}

idx += err;
- kunmap_atomic(saddr);
}

hifn_cipher_walk_exit(&rctx->walk);
--
2.1.4