Re: [PATCH 2/4] crypto: cavium - Fix the parameter of dma_unmap_sg()

Hi Herbert,


在 2021/3/3 16:59, Herbert Xu 写道:

On Tue, Feb 09, 2021 at 02:59:23PM +0800, chenxiang wrote:

quoted

From: Xiang Chen <redacted>

For function dma_unmap_sg(), the <nents> parameter should be number of
elements in the scatterlist prior to the mapping, not after the mapping.
So fix this usage.

Signed-off-by: Xiang Chen <redacted>
---
  drivers/crypto/cavium/nitrox/nitrox_reqmgr.c | 8 ++++----
  1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/crypto/cavium/nitrox/nitrox_reqmgr.c b/drivers/crypto/cavium/nitrox/nitrox_reqmgr.c
index 53ef067..1263194 100644
--- a/drivers/crypto/cavium/nitrox/nitrox_reqmgr.c
+++ b/drivers/crypto/cavium/nitrox/nitrox_reqmgr.c

@@ -170,7 +170,7 @@ static int dma_map_inbufs(struct nitrox_softreq *sr,
  		sr->in.total_bytes += sg_dma_len(sg);
  
  	sr->in.sg = req->src;
-	sr->in.sgmap_cnt = nents;
+	sr->in.sgmap_cnt = sg_nents(req->src);
  	ret = create_sg_component(sr, &sr->in, sr->in.sgmap_cnt);

So you're changing the count passed to create_sg_component.  Are you
sure that's correct? Even if it is correct you should change your
patch description to document this change.

Thank you for reminding me about this. I didn't notice that it changes 
the count passed to create_sg_component.
I have a change on this patch as follows, and please have a check on it:

--- a/drivers/crypto/cavium/nitrox/nitrox_reqmgr.c
+++ b/drivers/crypto/cavium/nitrox/nitrox_reqmgr.c

@@ -58,14 +58,14 @@ static void softreq_unmap_sgbufs(struct 

nitrox_softreq *sr)
         struct device *dev = DEV(ndev);


-       dma_unmap_sg(dev, sr->in.sg, sr->in.sgmap_cnt, DMA_BIDIRECTIONAL);
+       dma_unmap_sg(dev, sr->in.sg, sg_nents(sr->in.sg), 
DMA_BIDIRECTIONAL);
         dma_unmap_single(dev, sr->in.sgcomp_dma, sr->in.sgcomp_len,
                          DMA_TO_DEVICE);
         kfree(sr->in.sgcomp);
         sr->in.sg = NULL;
         sr->in.sgmap_cnt = 0;

-       dma_unmap_sg(dev, sr->out.sg, sr->out.sgmap_cnt,
+       dma_unmap_sg(dev, sr->out.sg, sg_nents(sr->out.sg),
                      DMA_BIDIRECTIONAL);
         dma_unmap_single(dev, sr->out.sgcomp_dma, sr->out.sgcomp_len,
                          DMA_TO_DEVICE);

@@ -178,7 +178,8 @@ static int dma_map_inbufs(struct nitrox_softreq *sr,
         return 0;

  incomp_err:
-       dma_unmap_sg(dev, req->src, nents, DMA_BIDIRECTIONAL);
+       dma_unmap_sg(dev, req->src, sg_nents(req->src),
+                    DMA_BIDIRECTIONAL);
         sr->in.sgmap_cnt = 0;
         return ret;
  }

@@ -203,7 +204,8 @@ static int dma_map_outbufs(struct nitrox_softreq *sr,
         return 0;

  outcomp_map_err:
-       dma_unmap_sg(dev, req->dst, nents, DMA_BIDIRECTIONAL);
+       dma_unmap_sg(dev, req->dst, sg_nents(req->dst),
+                    DMA_BIDIRECTIONAL);
         sr->out.sgmap_cnt = 0;
         sr->out.sg = NULL;
         return ret;