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>

1 files changed, 45 insertions, 32 deletions

diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 281f78553061..be84c94aaeae 100644
--- 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.