RDMA/mthca: Use for_each_sg_dma_page iterator on umem SGL

Use the for_each_sg_dma_page iterator variant to walk the umem DMA-mapped
SGL and get the page DMA address. This avoids the extra loop to iterate
pages in the SGE when for_each_sg iterator is used.

Additionally, purge umem->page_shift usage in the driver as its only
relevant for ODP MRs. Use system page size and shift instead.

Signed-off-by: Shiraz, Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/hw/mthca/mthca_provider.c b/drivers/infiniband/hw/mthca/mthca_provider.c
index 2c754bc..516c8cf 100644 (file)
--- a/drivers/infiniband/hw/mthca/mthca_provider.c
+++ b/drivers/infiniband/hw/mthca/mthca_provider.c
@@ -897,12 +897,11 @@ static struct ib_mr *mthca_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
                                       u64 virt, int acc, struct ib_udata *udata)
 {
        struct mthca_dev *dev = to_mdev(pd->device);
-       struct scatterlist *sg;
+       struct sg_dma_page_iter sg_iter;
        struct mthca_mr *mr;
        struct mthca_reg_mr ucmd;
        u64 *pages;
-       int shift, n, len;
-       int i, k, entry;
+       int n, i;
        int err = 0;
        int write_mtt_size;
 
@@ -929,7 +928,6 @@ static struct ib_mr *mthca_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
                goto err;
        }
 
-       shift = mr->umem->page_shift;
        n = mr->umem->nmap;
 
        mr->mtt = mthca_alloc_mtt(dev, n);
@@ -948,21 +946,19 @@ static struct ib_mr *mthca_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
 
        write_mtt_size = min(mthca_write_mtt_size(dev), (int) (PAGE_SIZE / sizeof *pages));
 
-       for_each_sg(mr->umem->sg_head.sgl, sg, mr->umem->nmap, entry) {
-               len = sg_dma_len(sg) >> shift;
-               for (k = 0; k < len; ++k) {
-                       pages[i++] = sg_dma_address(sg) + (k << shift);
-                       /*
-                        * Be friendly to write_mtt and pass it chunks
-                        * of appropriate size.
-                        */
-                       if (i == write_mtt_size) {
-                               err = mthca_write_mtt(dev, mr->mtt, n, pages, i);
-                               if (err)
-                                       goto mtt_done;
-                               n += i;
-                               i = 0;
-                       }
+       for_each_sg_dma_page(mr->umem->sg_head.sgl, &sg_iter, mr->umem->nmap, 0) {
+               pages[i++] = sg_page_iter_dma_address(&sg_iter);
+
+               /*
+                * Be friendly to write_mtt and pass it chunks
+                * of appropriate size.
+                */
+               if (i == write_mtt_size) {
+                       err = mthca_write_mtt(dev, mr->mtt, n, pages, i);
+                       if (err)
+                               goto mtt_done;
+                       n += i;
+                       i = 0;
                }
        }
 
@@ -973,7 +969,7 @@ mtt_done:
        if (err)
                goto err_mtt;
 
-       err = mthca_mr_alloc(dev, to_mpd(pd)->pd_num, shift, virt, length,
+       err = mthca_mr_alloc(dev, to_mpd(pd)->pd_num, PAGE_SHIFT, virt, length,
                             convert_access(acc), mr);
 
        if (err)