4
--- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
@@ -595,7 +595,7 @@ static int map_cont_bufs(struct rtrs_srv_path *srv_path)
 	     srv_path->mrs_num++) {
 		struct rtrs_srv_mr *srv_mr = &srv_path->mrs[srv_path->mrs_num];
 		struct scatterlist *s;
-		int nr, nr_sgt, chunks;
+		int nr, nr_sgt, chunks, ind;
 
 		sgt = &srv_mr->sgt;
 		chunks = chunks_per_mr * srv_path->mrs_num;
@@ -625,7 +625,7 @@ static int map_cont_bufs(struct rtrs_srv_path *srv_path)
 		}
 		nr = ib_map_mr_sg(mr, sgt->sgl, nr_sgt,
 				  NULL, max_chunk_size);
-		if (nr != nr_sgt) {
+		if (nr < nr_sgt) {
 			err = nr < 0 ? nr : -EINVAL;
 			goto dereg_mr;
 		}
@@ -641,9 +641,24 @@ static int map_cont_bufs(struct rtrs_srv_path *srv_path)
 				goto dereg_mr;
 			}
 		}
-		/* Eventually dma addr for each chunk can be cached */
-		for_each_sg(sgt->sgl, s, nr_sgt, i)
-			srv_path->dma_addr[chunks + i] = sg_dma_address(s);
+
+		/*
+		 * Cache DMA addresses by traversing sg entries.  If
+		 * regions were merged, an inner loop is required to
+		 * populate the DMA address array by traversing larger
+		 * regions.
+		 */
+		ind = chunks;
+		for_each_sg(sgt->sgl, s, nr_sgt, i) {
+			unsigned int dma_len = sg_dma_len(s);
+			u64 dma_addr = sg_dma_address(s);
+			u64 dma_addr_end = dma_addr + dma_len;
+
+			do {
+				srv_path->dma_addr[ind++] = dma_addr;
+				dma_addr += max_chunk_size;
+			} while (dma_addr < dma_addr_end);
+		}
 
 		ib_update_fast_reg_key(mr, ib_inc_rkey(mr->rkey));
 		srv_mr->mr = mr;
-- 
2.51.0[PATCH 6.19 461/781] RDMA/rtrs-srv: fix SG mappingGreg Kroah-Hartman <gregkh@linuxfoundation.org> undefinedstable@vger.kernel.org undefined undefined undefined undefined undefined undefined undefined’3†™%