IB/iser: Handle unaligned SG in separate function

[firefly-linux-kernel-4.4.55.git] / drivers / infiniband / ulp / iser / iser_memory.c

diff --git a/drivers/infiniband/ulp/iser/iser_memory.c b/drivers/infiniband/ulp/iser/iser_memory.c
index 797e49ff7f8ed475b9c45d40efa698acf8d0891d..4dea1ba1278f5d4ede84bd4b3bdcc065a8c12686 100644 (file)
--- a/drivers/infiniband/ulp/iser/iser_memory.c
+++ b/drivers/infiniband/ulp/iser/iser_memory.c
@@ -170,8 +170,8 @@ void iser_finalize_rdma_unaligned_sg(struct iscsi_iser_task *iser_task,
  */
 
 static int iser_sg_to_page_vec(struct iser_data_buf *data,
-                              struct iser_page_vec *page_vec,
-                              struct ib_device *ibdev)
+                              struct ib_device *ibdev, u64 *pages,
+                              int *offset, int *data_size)
 {
        struct scatterlist *sg, *sgl = (struct scatterlist *)data->buf;
        u64 start_addr, end_addr, page, chunk_start = 0;
@@ -180,7 +180,7 @@ static int iser_sg_to_page_vec(struct iser_data_buf *data,
        int i, new_chunk, cur_page, last_ent = data->dma_nents - 1;
 
        /* compute the offset of first element */
-       page_vec->offset = (u64) sgl[0].offset & ~MASK_4K;
+       *offset = (u64) sgl[0].offset & ~MASK_4K;
 
        new_chunk = 1;
        cur_page  = 0;
@@ -204,13 +204,14 @@ static int iser_sg_to_page_vec(struct iser_data_buf *data,
                   which might be unaligned */
                page = chunk_start & MASK_4K;
                do {
-                       page_vec->pages[cur_page++] = page;
+                       pages[cur_page++] = page;
                        page += SIZE_4K;
                } while (page < end_addr);
        }
 
-       page_vec->data_size = total_sz;
-       iser_dbg("page_vec->data_size:%d cur_page %d\n", page_vec->data_size,cur_page);
+       *data_size = total_sz;
+       iser_dbg("page_vec->data_size:%d cur_page %d\n",
+                *data_size, cur_page);
        return cur_page;
 }
 
@@ -295,8 +296,10 @@ static void iser_page_vec_build(struct iser_data_buf *data,
        page_vec->offset = 0;
 
        iser_dbg("Translating sg sz: %d\n", data->dma_nents);
-       page_vec_len = iser_sg_to_page_vec(data, page_vec, ibdev);
-       iser_dbg("sg len %d page_vec_len %d\n", data->dma_nents,page_vec_len);
+       page_vec_len = iser_sg_to_page_vec(data, ibdev, page_vec->pages,
+                                          &page_vec->offset,
+                                          &page_vec->data_size);
+       iser_dbg("sg len %d page_vec_len %d\n", data->dma_nents, page_vec_len);
 
        page_vec->length = page_vec_len;
 
@@ -344,6 +347,32 @@ void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task)
        }
 }
 
+static int fall_to_bounce_buf(struct iscsi_iser_task *iser_task,
+                             struct ib_device *ibdev,
+                             enum iser_data_dir cmd_dir,
+                             int aligned_len)
+{
+       struct iscsi_conn    *iscsi_conn = iser_task->iser_conn->iscsi_conn;
+       struct iser_data_buf *mem = &iser_task->data[cmd_dir];
+
+       iscsi_conn->fmr_unalign_cnt++;
+       iser_warn("rdma alignment violation (%d/%d aligned) or FMR not supported\n",
+                 aligned_len, mem->size);
+
+       if (iser_debug_level > 0)
+               iser_data_buf_dump(mem, ibdev);
+
+       /* unmap the command data before accessing it */
+       iser_dma_unmap_task_data(iser_task);
+
+       /* allocate copy buf, if we are writing, copy the */
+       /* unaligned scatterlist, dma map the copy        */
+       if (iser_start_rdma_unaligned_sg(iser_task, cmd_dir) != 0)
+                       return -ENOMEM;
+
+       return 0;
+}
+
 /**
  * iser_reg_rdma_mem - Registers memory intended for RDMA,
  * obtaining rkey and va
@@ -353,7 +382,6 @@ void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task)
 int iser_reg_rdma_mem(struct iscsi_iser_task *iser_task,
                      enum   iser_data_dir        cmd_dir)
 {
-       struct iscsi_conn    *iscsi_conn = iser_task->iser_conn->iscsi_conn;
        struct iser_conn     *ib_conn = iser_task->iser_conn->ib_conn;
        struct iser_device   *device = ib_conn->device;
        struct ib_device     *ibdev = device->ib_device;
@@ -369,20 +397,12 @@ int iser_reg_rdma_mem(struct iscsi_iser_task *iser_task,
        aligned_len = iser_data_buf_aligned_len(mem, ibdev);
        if (aligned_len != mem->dma_nents ||
            (!ib_conn->fmr_pool && mem->dma_nents > 1)) {
-               iscsi_conn->fmr_unalign_cnt++;
-               iser_dbg("rdma alignment violation (%d/%d aligned) or FMR not supported\n",
-                        aligned_len, mem->size);
-
-               if (iser_debug_level > 0)
-                       iser_data_buf_dump(mem, ibdev);
-
-               /* unmap the command data before accessing it */
-               iser_dma_unmap_task_data(iser_task);
-
-               /* allocate copy buf, if we are writing, copy the */
-               /* unaligned scatterlist, dma map the copy        */
-               if (iser_start_rdma_unaligned_sg(iser_task, cmd_dir) != 0)
-                               return -ENOMEM;
+               err = fall_to_bounce_buf(iser_task, ibdev,
+                                        cmd_dir, aligned_len);
+               if (err) {
+                       iser_err("failed to allocate bounce buffer\n");
+                       return err;
+               }
                mem = &iser_task->data_copy[cmd_dir];
        }