Re: [PATCH] accel/qaic: Fix the for loop used to walk SG table

[Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>]

Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>

On 10/4/2024 9:32 PM, Jeffrey Hugo wrote:
> From: Pranjal Ramajor Asha Kanojiya <quic_pkanojiy@quicinc.com>
> 
> Only for_each_sgtable_dma_sg() should be used to walk through a SG table
> to grab correct bus address and length pair after calling DMA MAP API on
> a SG table as DMA MAP APIs updates the SG table and for_each_sgtable_sg()
> walks through the original SG table.
> 
> Fixes: ff13be830333 ("accel/qaic: Add datapath")
> Fixes: 129776ac2e38 ("accel/qaic: Add control path")
> Signed-off-by: Pranjal Ramajor Asha Kanojiya <quic_pkanojiy@quicinc.com>
> Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
> Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
> ---
>  drivers/accel/qaic/qaic_control.c | 2 +-
>  drivers/accel/qaic/qaic_data.c    | 6 +++---
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/accel/qaic/qaic_control.c b/drivers/accel/qaic/qaic_control.c
> index 9e8a8cbadf6b..d8bdab69f800 100644
> --- a/drivers/accel/qaic/qaic_control.c
> +++ b/drivers/accel/qaic/qaic_control.c
> @@ -496,7 +496,7 @@ static int encode_addr_size_pairs(struct dma_xfer *xfer, struct wrapper_list *wr
>  	nents = sgt->nents;
>  	nents_dma = nents;
>  	*size = QAIC_MANAGE_EXT_MSG_LENGTH - msg_hdr_len - sizeof(**out_trans);
> -	for_each_sgtable_sg(sgt, sg, i) {
> +	for_each_sgtable_dma_sg(sgt, sg, i) {
>  		*size -= sizeof(*asp);
>  		/* Save 1K for possible follow-up transactions. */
>  		if (*size < SZ_1K) {
> diff --git a/drivers/accel/qaic/qaic_data.c b/drivers/accel/qaic/qaic_data.c
> index e86e71c1cdd8..c20eb63750f5 100644
> --- a/drivers/accel/qaic/qaic_data.c
> +++ b/drivers/accel/qaic/qaic_data.c
> @@ -184,7 +184,7 @@ static int clone_range_of_sgt_for_slice(struct qaic_device *qdev, struct sg_tabl
>  	nents = 0;
>  
>  	size = size ? size : PAGE_SIZE;
> -	for (sg = sgt_in->sgl; sg; sg = sg_next(sg)) {
> +	for_each_sgtable_dma_sg(sgt_in, sg, j) {
>  		len = sg_dma_len(sg);
>  
>  		if (!len)
> @@ -221,7 +221,7 @@ static int clone_range_of_sgt_for_slice(struct qaic_device *qdev, struct sg_tabl
>  
>  	/* copy relevant sg node and fix page and length */
>  	sgn = sgf;
> -	for_each_sgtable_sg(sgt, sg, j) {
> +	for_each_sgtable_dma_sg(sgt, sg, j) {
>  		memcpy(sg, sgn, sizeof(*sg));
>  		if (sgn == sgf) {
>  			sg_dma_address(sg) += offf;
> @@ -301,7 +301,7 @@ static int encode_reqs(struct qaic_device *qdev, struct bo_slice *slice,
>  	 * fence.
>  	 */
>  	dev_addr = req->dev_addr;
> -	for_each_sgtable_sg(slice->sgt, sg, i) {
> +	for_each_sgtable_dma_sg(slice->sgt, sg, i) {
>  		slice->reqs[i].cmd = cmd;
>  		slice->reqs[i].src_addr = cpu_to_le64(slice->dir == DMA_TO_DEVICE ?
>  						      sg_dma_address(sg) : dev_addr);