[PATCH v8 5/8] crypto: caam - check if RNG job failed

From: Andrey Smirnov
Date: Mon Mar 16 2020 - 11:01:21 EST


We shouldn't stay silent if RNG job fails. Add appropriate code to
check for that case and propagate error code up appropriately.

Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
Cc: Chris Healy <cphealy@xxxxxxxxx>
Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
Cc: Horia GeantÄ <horia.geanta@xxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: Iuliana Prodan <iuliana.prodan@xxxxxxx>
Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-imx@xxxxxxx
---
drivers/crypto/caam/caamrng.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/caam/caamrng.c b/drivers/crypto/caam/caamrng.c
index b3b92e5944cd..ffbdc912f1be 100644
--- a/drivers/crypto/caam/caamrng.c
+++ b/drivers/crypto/caam/caamrng.c
@@ -44,6 +44,11 @@ struct caam_rng_ctx {
struct kfifo fifo;
};

+struct caam_rng_job_ctx {
+ struct completion *done;
+ int *err;
+};
+
static struct caam_rng_ctx *to_caam_rng_ctx(struct hwrng *r)
{
return (struct caam_rng_ctx *)r->priv;
@@ -52,12 +57,12 @@ static struct caam_rng_ctx *to_caam_rng_ctx(struct hwrng *r)
static void caam_rng_done(struct device *jrdev, u32 *desc, u32 err,
void *context)
{
- struct completion *done = context;
+ struct caam_rng_job_ctx *jctx = context;

if (err)
- caam_jr_strstatus(jrdev, err);
+ *jctx->err = caam_jr_strstatus(jrdev, err);

- complete(done);
+ complete(jctx->done);
}

static u32 *caam_init_desc(u32 *desc, dma_addr_t dst_dma, int len)
@@ -80,7 +85,11 @@ static int caam_rng_read_one(struct device *jrdev,
struct completion *done)
{
dma_addr_t dst_dma;
- int err;
+ int err, ret = 0;
+ struct caam_rng_job_ctx jctx = {
+ .done = done,
+ .err = &ret,
+ };

len = min_t(int, len, CAAM_RNG_MAX_FIFO_STORE_SIZE);

@@ -93,7 +102,7 @@ static int caam_rng_read_one(struct device *jrdev,
init_completion(done);
err = caam_jr_enqueue(jrdev,
caam_init_desc(desc, dst_dma, len),
- caam_rng_done, done);
+ caam_rng_done, &jctx);
if (err == -EINPROGRESS) {
wait_for_completion(done);
err = 0;
@@ -101,7 +110,7 @@ static int caam_rng_read_one(struct device *jrdev,

dma_unmap_single(jrdev, dst_dma, len, DMA_FROM_DEVICE);

- return err ?: len;
+ return err ?: (ret ?: len);
}

static void caam_rng_fill_async(struct caam_rng_ctx *ctx)
--
2.21.0