- } else if (srp_map_fmr(target, scat, count, req,
- (void *) cmd->add_data)) {
- /*
- * FMR mapping failed, and the scatterlist has more
- * than one entry. Generate an indirect memory
- * descriptor.
- */
- struct srp_indirect_buf *buf = (void *) cmd->add_data;
- struct scatterlist *sg;
- u32 datalen = 0;
- int i;
-
- fmt = SRP_DATA_DESC_INDIRECT;
- len = sizeof (struct srp_cmd) +
- sizeof (struct srp_indirect_buf) +
- count * sizeof (struct srp_direct_buf);
-
- scsi_for_each_sg(scmnd, sg, count, i) {
- unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
-
- buf->desc_list[i].va =
- cpu_to_be64(ib_sg_dma_address(ibdev, sg));
- buf->desc_list[i].key =
- cpu_to_be32(target->rkey);
- buf->desc_list[i].len = cpu_to_be32(dma_len);
- datalen += dma_len;
+
+ req->nfmr = 0;
+ goto map_complete;
+ }
+
+ /* We have more than one scatter/gather entry, so build our indirect
+ * descriptor table, trying to merge as many entries with FMR as we
+ * can.
+ */
+ indirect_hdr = (void *) cmd->add_data;
+
+ memset(&state, 0, sizeof(state));
+ state.desc = indirect_hdr->desc_list;
+ state.pages = req->map_page;
+ state.next_fmr = req->fmr_list;
+
+ use_fmr = dev->fmr_pool ? SRP_MAP_ALLOW_FMR : SRP_MAP_NO_FMR;
+
+ for_each_sg(scat, sg, count, i) {
+ if (srp_map_sg_entry(&state, target, sg, i, use_fmr)) {
+ /* FMR mapping failed, so backtrack to the first
+ * unmapped entry and continue on without using FMR.
+ */
+ dma_addr_t dma_addr;
+ unsigned int dma_len;
+
+backtrack:
+ sg = state.unmapped_sg;
+ i = state.unmapped_index;
+
+ dma_addr = ib_sg_dma_address(ibdev, sg);
+ dma_len = ib_sg_dma_len(ibdev, sg);
+ dma_len -= (state.unmapped_addr - dma_addr);
+ dma_addr = state.unmapped_addr;
+ use_fmr = SRP_MAP_NO_FMR;
+ srp_map_desc(&state, dma_addr, dma_len, target->rkey);