IB/core: Enhance ib_map_mr_sg()

[deliverable/linux.git] / drivers / infiniband / hw / mlx5 / mr.c

diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
index 4d5bff151cdf09957942f35255d84df2286f572b..8cf2ce50511f935e6043bea4ebaa4af3a980661c 100644 (file)
--- a/drivers/infiniband/hw/mlx5/mr.c
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -1751,26 +1751,33 @@ done:
 static int
 mlx5_ib_sg_to_klms(struct mlx5_ib_mr *mr,
                   struct scatterlist *sgl,
-                  unsigned short sg_nents)
+                  unsigned short sg_nents,
+                  unsigned int *sg_offset_p)
 {
        struct scatterlist *sg = sgl;
        struct mlx5_klm *klms = mr->descs;
+       unsigned int sg_offset = sg_offset_p ? *sg_offset_p : 0;
        u32 lkey = mr->ibmr.pd->local_dma_lkey;
        int i;
 
-       mr->ibmr.iova = sg_dma_address(sg);
+       mr->ibmr.iova = sg_dma_address(sg) + sg_offset;
        mr->ibmr.length = 0;
        mr->ndescs = sg_nents;
 
        for_each_sg(sgl, sg, sg_nents, i) {
                if (unlikely(i > mr->max_descs))
                        break;
-               klms[i].va = cpu_to_be64(sg_dma_address(sg));
-               klms[i].bcount = cpu_to_be32(sg_dma_len(sg));
+               klms[i].va = cpu_to_be64(sg_dma_address(sg) + sg_offset);
+               klms[i].bcount = cpu_to_be32(sg_dma_len(sg) - sg_offset);
                klms[i].key = cpu_to_be32(lkey);
                mr->ibmr.length += sg_dma_len(sg);
+
+               sg_offset = 0;
        }
 
+       if (sg_offset_p)
+               *sg_offset_p = sg_offset;
+
        return i;
 }
 
@@ -1788,9 +1795,8 @@ static int mlx5_set_page(struct ib_mr *ibmr, u64 addr)
        return 0;
 }
 
-int mlx5_ib_map_mr_sg(struct ib_mr *ibmr,
-                     struct scatterlist *sg,
-                     int sg_nents)
+int mlx5_ib_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg, int sg_nents,
+                     unsigned int *sg_offset)
 {
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        int n;
@@ -1802,9 +1808,10 @@ int mlx5_ib_map_mr_sg(struct ib_mr *ibmr,
                                   DMA_TO_DEVICE);
 
        if (mr->access_mode == MLX5_ACCESS_MODE_KLM)
-               n = mlx5_ib_sg_to_klms(mr, sg, sg_nents);
+               n = mlx5_ib_sg_to_klms(mr, sg, sg_nents, sg_offset);
        else
-               n = ib_sg_to_pages(ibmr, sg, sg_nents, mlx5_set_page);
+               n = ib_sg_to_pages(ibmr, sg, sg_nents, sg_offset,
+                               mlx5_set_page);
 
        ib_dma_sync_single_for_device(ibmr->device, mr->desc_map,
                                      mr->desc_size * mr->max_descs,