IB/srp: Introduce srp_map_fmr()

This patch does not change any functionality.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 281f785..be84c94 100644 (file)
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -1047,12 +1047,54 @@ static int srp_map_sg_entry(struct srp_map_state *state,
        return ret;
 }
 
+static void srp_map_fmr(struct srp_map_state *state,
+                       struct srp_target_port *target, struct srp_request *req,
+                       struct scatterlist *scat, int count)
+{
+       struct srp_device *dev = target->srp_host->srp_dev;
+       struct ib_device *ibdev = dev->dev;
+       struct scatterlist *sg;
+       int i, use_fmr;
+
+       state->desc     = req->indirect_desc;
+       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);
+               }
+       }
+
+       if (use_fmr == SRP_MAP_ALLOW_FMR && srp_map_finish_fmr(state, target))
+               goto backtrack;
+
+       req->nfmr = state->nfmr;
+}
+
 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
                        struct srp_request *req)
 {
-       struct scatterlist *scat, *sg;
+       struct scatterlist *scat;
        struct srp_cmd *cmd = req->cmd->buf;
-       int i, len, nents, count, use_fmr;
+       int len, nents, count;
        struct srp_device *dev;
        struct ib_device *ibdev;
        struct srp_map_state state;
@@ -1111,35 +1153,7 @@ static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
                                   target->indirect_size, DMA_TO_DEVICE);
 
        memset(&state, 0, sizeof(state));
-       state.desc      = req->indirect_desc;
-       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);
-               }
-       }
-
-       if (use_fmr == SRP_MAP_ALLOW_FMR && srp_map_finish_fmr(&state, target))
-               goto backtrack;
+       srp_map_fmr(&state, target, req, scat, count);
 
        /* We've mapped the request, now pull as much of the indirect
         * descriptor table as we can into the command buffer. If this
@@ -1147,7 +1161,6 @@ backtrack:
         * guaranteed to fit into the command, as the SCSI layer won't
         * give us more S/G entries than we allow.
         */
-       req->nfmr = state.nfmr;
        if (state.ndesc == 1) {
                /* FMR mapping was able to collapse this to one entry,
                 * so use a direct descriptor.