iser-target: Split and properly type the login buffer

The login receive buffer is used as a iser_rx_desc, so type it as such
in struct isert_conn and allocate the exactly right space for it.  The
TX buffer is moved to a separate variable and properly sized as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

2 files changed, 29 insertions, 30 deletions

diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index 838d16ded772..ac3e80c55965 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -597,10 +597,12 @@ isert_free_login_buf(struct isert_conn *isert_conn)
 
         ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
                             ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
+        kfree(isert_conn->login_rsp_buf);
+
         ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
-                            ISCSI_DEF_MAX_RECV_SEG_LEN,
+                            ISER_RX_PAYLOAD_SIZE,
                             DMA_FROM_DEVICE);
-        kfree(isert_conn->login_buf);
+        kfree(isert_conn->login_req_buf);
 }
 
 static int
@@ -609,50 +611,48 @@ isert_alloc_login_buf(struct isert_conn *isert_conn,
 {
         int ret;
 
-        isert_conn->login_buf = kzalloc(ISCSI_DEF_MAX_RECV_SEG_LEN +
-                                        ISER_RX_PAYLOAD_SIZE, GFP_KERNEL);
-        if (!isert_conn->login_buf) {
+        isert_conn->login_req_buf = kzalloc(sizeof(*isert_conn->login_req_buf),
+                        GFP_KERNEL);
+        if (!isert_conn->login_req_buf) {
                 isert_err("Unable to allocate isert_conn->login_buf\n");
                 return -ENOMEM;
         }
 
-        isert_conn->login_req_buf = isert_conn->login_buf;
-        isert_conn->login_rsp_buf = isert_conn->login_buf +
-                                    ISCSI_DEF_MAX_RECV_SEG_LEN;
-
-        isert_dbg("Set login_buf: %p login_req_buf: %p login_rsp_buf: %p\n",
-                 isert_conn->login_buf, isert_conn->login_req_buf,
-                 isert_conn->login_rsp_buf);
-
         isert_conn->login_req_dma = ib_dma_map_single(ib_dev,
-                                (void *)isert_conn->login_req_buf,
-                                ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_FROM_DEVICE);
-
+                                isert_conn->login_req_buf,
+                                ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
         ret = ib_dma_mapping_error(ib_dev, isert_conn->login_req_dma);
         if (ret) {
                 isert_err("login_req_dma mapping error: %d\n", ret);
                 isert_conn->login_req_dma = 0;
-                goto out_login_buf;
+                goto out_free_login_req_buf;
+        }
+
+        isert_conn->login_rsp_buf = kzalloc(ISER_RX_PAYLOAD_SIZE, GFP_KERNEL);
+        if (!isert_conn->login_rsp_buf) {
+                isert_err("Unable to allocate isert_conn->login_rspbuf\n");
+                goto out_unmap_login_req_buf;
         }
 
         isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev,
-                                        (void *)isert_conn->login_rsp_buf,
+                                        isert_conn->login_rsp_buf,
                                         ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
-
         ret = ib_dma_mapping_error(ib_dev, isert_conn->login_rsp_dma);
         if (ret) {
                 isert_err("login_rsp_dma mapping error: %d\n", ret);
                 isert_conn->login_rsp_dma = 0;
-                goto out_req_dma_map;
+                goto out_free_login_rsp_buf;
         }
 
         return 0;
 
-out_req_dma_map:
+out_free_login_rsp_buf:
+        kfree(isert_conn->login_rsp_buf);
+out_unmap_login_req_buf:
         ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
-                            ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_FROM_DEVICE);
-out_login_buf:
-        kfree(isert_conn->login_buf);
+                            ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
+out_free_login_req_buf:
+        kfree(isert_conn->login_req_buf);
         return ret;
 }
 
@@ -773,7 +773,7 @@ isert_connect_release(struct isert_conn *isert_conn)
                 ib_destroy_qp(isert_conn->qp);
         }
 
-        if (isert_conn->login_buf)
+        if (isert_conn->login_req_buf)
                 isert_free_login_buf(isert_conn);
 
         isert_device_put(device);
@@ -1216,7 +1216,7 @@ post_send:
 static void
 isert_rx_login_req(struct isert_conn *isert_conn)
 {
-        struct iser_rx_desc *rx_desc = (void *)isert_conn->login_req_buf;
+        struct iser_rx_desc *rx_desc = isert_conn->login_req_buf;
         int rx_buflen = isert_conn->login_req_len;
         struct iscsi_conn *conn = isert_conn->conn;
         struct iscsi_login *login = conn->conn_login;
@@ -1594,7 +1594,7 @@ isert_rcv_completion(struct iser_rx_desc *desc,
         u64 rx_dma;
         int rx_buflen;
 
-        if ((char *)desc == isert_conn->login_req_buf) {
+        if (desc == isert_conn->login_req_buf) {
                 rx_dma = isert_conn->login_req_dma;
                 rx_buflen = ISER_RX_PAYLOAD_SIZE;
                 isert_dbg("login_buf: Using rx_dma: 0x%llx, rx_buflen: %d\n",
@@ -1613,7 +1613,7 @@ isert_rcv_completion(struct iser_rx_desc *desc,
                  hdr->opcode, hdr->itt, hdr->flags,
                  (int)(xfer_len - ISER_HEADERS_LEN));
 
-        if ((char *)desc == isert_conn->login_req_buf) {
+        if (desc == isert_conn->login_req_buf) {
                 isert_conn->login_req_len = xfer_len - ISER_HEADERS_LEN;
                 if (isert_conn->conn) {
                         struct iscsi_login *login = isert_conn->conn->conn_login;
diff --git a/drivers/infiniband/ulp/isert/ib_isert.h b/drivers/infiniband/ulp/isert/ib_isert.h
index 2ef2d6cdbe52..6c2c5fa85d2f 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.h
+++ b/drivers/infiniband/ulp/isert/ib_isert.h
@@ -182,8 +182,7 @@ struct isert_conn {
         u32                     initiator_depth;
         bool                    pi_support;
         u32                     max_sge;
-        char                    *login_buf;
-        char                    *login_req_buf;
+        struct iser_rx_desc     *login_req_buf;
         char                    *login_rsp_buf;
         u64                     login_req_dma;
         int                     login_req_len;