Re: [PATCH] crypto: qce: dma_map_sg can handle chained SG

[LABBE Corentin <clabbe.montjoie@gmail.com>]

On Tue, Nov 03, 2015 at 12:39:57PM +0200, Stanimir Varbanov wrote:
> Hi,
> 
> I know that this patch has been queued up, but ...
> 
> On 10/02/2015 09:01 AM, LABBE Corentin wrote:
> > The qce driver use two dma_map_sg path according to SG are chained
> > or not.
> > Since dma_map_sg can handle both case, clean the code with all
> > references to sg chained.
> > 
> > Thus removing qce_mapsg, qce_unmapsg and qce_countsg functions.
> > 
> > Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
> > ---
> >  drivers/crypto/qce/ablkcipher.c | 30 ++++++++----------------
> >  drivers/crypto/qce/cipher.h     |  4 ----
> >  drivers/crypto/qce/dma.c        | 52 -----------------------------------------
> >  drivers/crypto/qce/dma.h        |  5 ----
> >  drivers/crypto/qce/sha.c        | 18 ++++++--------
> >  drivers/crypto/qce/sha.h        |  2 --
> >  6 files changed, 17 insertions(+), 94 deletions(-)
> > 
> 
> <snip>
> 
> > diff --git a/drivers/crypto/qce/sha.c b/drivers/crypto/qce/sha.c
> > index be2f504..0c9973e 100644
> > --- a/drivers/crypto/qce/sha.c
> > +++ b/drivers/crypto/qce/sha.c
> > @@ -51,9 +51,8 @@ static void qce_ahash_done(void *data)
> >  	if (error)
> >  		dev_dbg(qce->dev, "ahash dma termination error (%d)\n", error);
> >  
> > -	qce_unmapsg(qce->dev, req->src, rctx->src_nents, DMA_TO_DEVICE,
> > -		    rctx->src_chained);
> > -	qce_unmapsg(qce->dev, &rctx->result_sg, 1, DMA_FROM_DEVICE, 0);
> > +	dma_unmap_sg(qce->dev, req->src, rctx->src_nents, DMA_TO_DEVICE);
> > +	dma_unmap_sg(qce->dev, &rctx->result_sg, 1, DMA_FROM_DEVICE);
> >  
> >  	memcpy(rctx->digest, result->auth_iv, digestsize);
> >  	if (req->result)
> > @@ -92,16 +91,14 @@ static int qce_ahash_async_req_handle(struct crypto_async_request *async_req)
> >  		rctx->authklen = AES_KEYSIZE_128;
> >  	}
> >  
> > -	rctx->src_nents = qce_countsg(req->src, req->nbytes,
> > -				      &rctx->src_chained);
> > -	ret = qce_mapsg(qce->dev, req->src, rctx->src_nents, DMA_TO_DEVICE,
> > -			rctx->src_chained);
> > +	rctx->src_nents = sg_nents_for_len(req->src, req->nbytes);
> 
> sg_nents_for_len can return -EINVAL, and this error should be handled.
> 
> After added a check for the error I'm observing below:
> 
> #insmod tcrypt.ko mode=403 (test_ahash_speed("sha1"))
> 
> test 21 ( 8192 byte blocks, 8192 bytes per update,   1 updates):
> qcrypto 73a000.crypto: sg_nents_for_len failed (-22) (nbytes:8192,
> sg_len:4096)
> hashing failed ret=-22
> 
> It seems that something is wrong with the test case? Looking further in
> test_hash_sg_init() we can see:
> 
> #define TVMEMSIZE	4
> 
> 	sg_init_table(sg, TVMEMSIZE);
> 	for (i = 0; i < TVMEMSIZE; i++) {
> 		sg_set_buf(sg + i, tvmem[i], PAGE_SIZE);
> 		memset(tvmem[i], 0xff, PAGE_SIZE);
> 	}
> 
> so we have 4 SGs with sg->length = 4096, thus sg_nents_for_len() should
> return 2 entries with 4096 bytes each.
> 
> What is wrong here?
> 

Hello

It is a shame that I forgot to check the return value.
Herbert, do you prefer to drop the patch series and I send an updated one, or does I will send a new patch series for checking the return value of sg_nents_for_len() ?

Regards

LABBE Corentin