IB/iser: Generalize rdma memory registration

Currently the driver uses FMRs as the only means to register the
memory pointed by SG provided by the SCSI mid-layer with the RDMA
device.

As preparation step for adding more methods for fast path memory
registration, make the alloc/free and reg/unreg calls function
pointers, which are for now just set to the existing FMR ones.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 16 insertions, 18 deletions

diff --git a/drivers/infiniband/ulp/iser/iser_initiator.c b/drivers/infiniband/ulp/iser/iser_initiator.c
index 5c2b142840de..bdc38f423ca2 100644
--- a/drivers/infiniband/ulp/iser/iser_initiator.c
+++ b/drivers/infiniband/ulp/iser/iser_initiator.c
@@ -49,6 +49,7 @@ static int iser_prepare_read_cmd(struct iscsi_task *task,
 
 {
         struct iscsi_iser_task *iser_task = task->dd_data;
+        struct iser_device  *device = iser_task->iser_conn->ib_conn->device;
         struct iser_regd_buf *regd_buf;
         int err;
         struct iser_hdr *hdr = &iser_task->desc.iser_header;
@@ -69,7 +70,7 @@ static int iser_prepare_read_cmd(struct iscsi_task *task,
                 return -EINVAL;
         }
 
-        err = iser_reg_rdma_mem(iser_task,ISER_DIR_IN);
+        err = device->iser_reg_rdma_mem(iser_task, ISER_DIR_IN);
         if (err) {
                 iser_err("Failed to set up Data-IN RDMA\n");
                 return err;
@@ -98,6 +99,7 @@ iser_prepare_write_cmd(struct iscsi_task *task,
                        unsigned int edtl)
 {
         struct iscsi_iser_task *iser_task = task->dd_data;
+        struct iser_device  *device = iser_task->iser_conn->ib_conn->device;
         struct iser_regd_buf *regd_buf;
         int err;
         struct iser_hdr *hdr = &iser_task->desc.iser_header;
@@ -119,7 +121,7 @@ iser_prepare_write_cmd(struct iscsi_task *task,
                 return -EINVAL;
         }
 
-        err = iser_reg_rdma_mem(iser_task,ISER_DIR_OUT);
+        err = device->iser_reg_rdma_mem(iser_task, ISER_DIR_OUT);
         if (err != 0) {
                 iser_err("Failed to register write cmd RDMA mem\n");
                 return err;
@@ -253,8 +255,8 @@ int iser_alloc_rx_descriptors(struct iser_conn *ib_conn, struct iscsi_session *s
         ib_conn->qp_max_recv_dtos_mask = session->cmds_max - 1; /* cmds_max is 2^N */
         ib_conn->min_posted_rx = ib_conn->qp_max_recv_dtos >> 2;
 
-        if (iser_create_fmr_pool(ib_conn, session->scsi_cmds_max))
-                goto create_fmr_pool_failed;
+        if (device->iser_alloc_rdma_reg_res(ib_conn, session->scsi_cmds_max))
+                goto create_rdma_reg_res_failed;
 
         if (iser_alloc_login_buf(ib_conn))
                 goto alloc_login_buf_fail;
@@ -293,8 +295,8 @@ rx_desc_dma_map_failed:
 rx_desc_alloc_fail:
         iser_free_login_buf(ib_conn);
 alloc_login_buf_fail:
-        iser_free_fmr_pool(ib_conn);
-create_fmr_pool_failed:
+        device->iser_free_rdma_reg_res(ib_conn);
+create_rdma_reg_res_failed:
         iser_err("failed allocating rx descriptors / data buffers\n");
         return -ENOMEM;
 }
@@ -308,6 +310,9 @@ void iser_free_rx_descriptors(struct iser_conn *ib_conn)
         if (!ib_conn->rx_descs)
                 goto free_login_buf;
 
+        if (device && device->iser_free_rdma_reg_res)
+                device->iser_free_rdma_reg_res(ib_conn);
+
         rx_desc = ib_conn->rx_descs;
         for (i = 0; i < ib_conn->qp_max_recv_dtos; i++, rx_desc++)
                 ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
@@ -318,7 +323,6 @@ void iser_free_rx_descriptors(struct iser_conn *ib_conn)
 
 free_login_buf:
         iser_free_login_buf(ib_conn);
-        iser_free_fmr_pool(ib_conn);
 }
 
 static int iser_post_rx_bufs(struct iscsi_conn *conn, struct iscsi_hdr *req)
@@ -629,8 +633,8 @@ void iser_task_rdma_init(struct iscsi_iser_task *iser_task)
 
 void iser_task_rdma_finalize(struct iscsi_iser_task *iser_task)
 {
+        struct iser_device *device = iser_task->iser_conn->ib_conn->device;
         int is_rdma_aligned = 1;
-        struct iser_regd_buf *regd;
 
         /* if we were reading, copy back to unaligned sglist,
          * anyway dma_unmap and free the copy
@@ -644,17 +648,11 @@ void iser_task_rdma_finalize(struct iscsi_iser_task *iser_task)
                 iser_finalize_rdma_unaligned_sg(iser_task, ISER_DIR_OUT);
         }
 
-        if (iser_task->dir[ISER_DIR_IN]) {
-                regd = &iser_task->rdma_regd[ISER_DIR_IN];
-                if (regd->reg.is_fmr)
-                        iser_unreg_mem(&regd->reg);
-        }
+        if (iser_task->dir[ISER_DIR_IN])
+                device->iser_unreg_rdma_mem(iser_task, ISER_DIR_IN);
 
-        if (iser_task->dir[ISER_DIR_OUT]) {
-                regd = &iser_task->rdma_regd[ISER_DIR_OUT];
-                if (regd->reg.is_fmr)
-                        iser_unreg_mem(&regd->reg);
-        }
+        if (iser_task->dir[ISER_DIR_OUT])
+                device->iser_unreg_rdma_mem(iser_task, ISER_DIR_OUT);
 
        /* if the data was unaligned, it was already unmapped and then copied */
        if (is_rdma_aligned)