iscsi/iser-target: Convert to command priv_size usage

This command converts iscsi/isert-target to use allocations based on
iscsit_transport->priv_size within iscsit_allocate_cmd(), instead of
using an embedded isert_cmd->iscsi_cmd.

This includes removing iscsit_transport->alloc_cmd() usage, along
with updating isert-target code to use iscsit_priv_cmd().

Also, remove left-over iscsit_transport->release_cmd() usage for
direct calls to iscsit_release_cmd(), and drop the now unused
lio_cmd_cache and isert_cmd_cache.

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>

2 files changed, 41 insertions, 75 deletions

diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index c42748b3b257..027a818f287b 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -39,7 +39,6 @@ static DEFINE_MUTEX(device_list_mutex);
 static LIST_HEAD(device_list);
 static struct workqueue_struct *isert_rx_wq;
 static struct workqueue_struct *isert_comp_wq;
-static struct kmem_cache *isert_cmd_cache;
 
 static void
 isert_qp_event_callback(struct ib_event *e, void *context)
@@ -876,43 +875,30 @@ isert_rx_login_req(struct iser_rx_desc *rx_desc, int rx_buflen,
         schedule_delayed_work(&conn->login_work, 0);
 }
 
-static void
-isert_release_cmd(struct iscsi_cmd *cmd)
-{
-        struct isert_cmd *isert_cmd = container_of(cmd, struct isert_cmd,
-                                                   iscsi_cmd);
-
-        pr_debug("Entering isert_release_cmd %p >>>>>>>>>>>>>>>.\n", isert_cmd);
-
-        kfree(cmd->buf_ptr);
-        kfree(cmd->tmr_req);
-
-        kmem_cache_free(isert_cmd_cache, isert_cmd);
-}
-
 static struct iscsi_cmd
-*isert_alloc_cmd(struct iscsi_conn *conn, gfp_t gfp)
+*isert_allocate_cmd(struct iscsi_conn *conn, gfp_t gfp)
 {
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct isert_cmd *isert_cmd;
+        struct iscsi_cmd *cmd;
 
-        isert_cmd = kmem_cache_zalloc(isert_cmd_cache, gfp);
-        if (!isert_cmd) {
-                pr_err("Unable to allocate isert_cmd\n");
+        cmd = iscsit_allocate_cmd(conn, gfp);
+        if (!cmd) {
+                pr_err("Unable to allocate iscsi_cmd + isert_cmd\n");
                 return NULL;
         }
+        isert_cmd = iscsit_priv_cmd(cmd);
         isert_cmd->conn = isert_conn;
-        isert_cmd->iscsi_cmd.release_cmd = &isert_release_cmd;
+        isert_cmd->iscsi_cmd = cmd;
 
-        return &isert_cmd->iscsi_cmd;
+        return cmd;
 }
 
 static int
 isert_handle_scsi_cmd(struct isert_conn *isert_conn,
-                      struct isert_cmd *isert_cmd, struct iser_rx_desc *rx_desc,
-                      unsigned char *buf)
+                      struct isert_cmd *isert_cmd, struct iscsi_cmd *cmd,
+                      struct iser_rx_desc *rx_desc, unsigned char *buf)
 {
-        struct iscsi_cmd *cmd = &isert_cmd->iscsi_cmd;
         struct iscsi_conn *conn = isert_conn->conn;
         struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
         struct scatterlist *sg;
@@ -1019,9 +1005,9 @@ isert_handle_iscsi_dataout(struct isert_conn *isert_conn,
 
 static int
 isert_handle_nop_out(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
-                     struct iser_rx_desc *rx_desc, unsigned char *buf)
+                     struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
+                     unsigned char *buf)
 {
-        struct iscsi_cmd *cmd = &isert_cmd->iscsi_cmd;
         struct iscsi_conn *conn = isert_conn->conn;
         struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
         int rc;
@@ -1038,9 +1024,9 @@ isert_handle_nop_out(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
 
 static int
 isert_handle_text_cmd(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
-                      struct iser_rx_desc *rx_desc, struct iscsi_text *hdr)
+                      struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
+                      struct iscsi_text *hdr)
 {
-        struct iscsi_cmd *cmd = &isert_cmd->iscsi_cmd;
         struct iscsi_conn *conn = isert_conn->conn;
         u32 payload_length = ntoh24(hdr->dlength);
         int rc;
@@ -1085,26 +1071,26 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
 
         switch (opcode) {
         case ISCSI_OP_SCSI_CMD:
-                cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
+                cmd = isert_allocate_cmd(conn, GFP_KERNEL);
                 if (!cmd)
                         break;
 
-                isert_cmd = container_of(cmd, struct isert_cmd, iscsi_cmd);
+                isert_cmd = iscsit_priv_cmd(cmd);
                 isert_cmd->read_stag = read_stag;
                 isert_cmd->read_va = read_va;
                 isert_cmd->write_stag = write_stag;
                 isert_cmd->write_va = write_va;
 
-                ret = isert_handle_scsi_cmd(isert_conn, isert_cmd,
+                ret = isert_handle_scsi_cmd(isert_conn, isert_cmd, cmd,
                                         rx_desc, (unsigned char *)hdr);
                 break;
         case ISCSI_OP_NOOP_OUT:
-                cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
+                cmd = isert_allocate_cmd(conn, GFP_KERNEL);
                 if (!cmd)
                         break;
 
-                isert_cmd = container_of(cmd, struct isert_cmd, iscsi_cmd);
-                ret = isert_handle_nop_out(isert_conn, isert_cmd,
+                isert_cmd = iscsit_priv_cmd(cmd);
+                ret = isert_handle_nop_out(isert_conn, isert_cmd, cmd,
                                            rx_desc, (unsigned char *)hdr);
                 break;
         case ISCSI_OP_SCSI_DATA_OUT:
@@ -1112,7 +1098,7 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
                                                 (unsigned char *)hdr);
                 break;
         case ISCSI_OP_SCSI_TMFUNC:
-                cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
+                cmd = isert_allocate_cmd(conn, GFP_KERNEL);
                 if (!cmd)
                         break;
 
@@ -1120,7 +1106,7 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
                                                 (unsigned char *)hdr);
                 break;
         case ISCSI_OP_LOGOUT:
-                cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
+                cmd = isert_allocate_cmd(conn, GFP_KERNEL);
                 if (!cmd)
                         break;
 
@@ -1131,12 +1117,12 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
                                                     HZ);
                 break;
         case ISCSI_OP_TEXT:
-                cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
+                cmd = isert_allocate_cmd(conn, GFP_KERNEL);
                 if (!cmd)
                         break;
 
-                isert_cmd = container_of(cmd, struct isert_cmd, iscsi_cmd);
-                ret = isert_handle_text_cmd(isert_conn, isert_cmd,
+                isert_cmd = iscsit_priv_cmd(cmd);
+                ret = isert_handle_text_cmd(isert_conn, isert_cmd, cmd,
                                             rx_desc, (struct iscsi_text *)hdr);
                 break;
         default:
@@ -1264,7 +1250,7 @@ isert_unmap_cmd(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn)
 static void
 isert_put_cmd(struct isert_cmd *isert_cmd)
 {
-        struct iscsi_cmd *cmd = &isert_cmd->iscsi_cmd;
+        struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
         struct isert_conn *isert_conn = isert_cmd->conn;
         struct iscsi_conn *conn = isert_conn->conn;
 
@@ -1315,7 +1301,7 @@ isert_put_cmd(struct isert_cmd *isert_cmd)
                  * Fall-through
                  */
         default:
-                isert_release_cmd(cmd);
+                iscsit_release_cmd(cmd);
                 break;
         }
 }
@@ -1351,7 +1337,7 @@ isert_completion_rdma_read(struct iser_tx_desc *tx_desc,
                            struct isert_cmd *isert_cmd)
 {
         struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
-        struct iscsi_cmd *cmd = &isert_cmd->iscsi_cmd;
+        struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
         struct se_cmd *se_cmd = &cmd->se_cmd;
         struct ib_device *ib_dev = isert_cmd->conn->conn_cm_id->device;
 
@@ -1387,7 +1373,7 @@ isert_do_control_comp(struct work_struct *work)
                         struct isert_cmd, comp_work);
         struct isert_conn *isert_conn = isert_cmd->conn;
         struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
-        struct iscsi_cmd *cmd = &isert_cmd->iscsi_cmd;
+        struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
 
         switch (cmd->i_state) {
         case ISTATE_SEND_TASKMGTRSP:
@@ -1433,7 +1419,7 @@ isert_response_completion(struct iser_tx_desc *tx_desc,
                           struct isert_conn *isert_conn,
                           struct ib_device *ib_dev)
 {
-        struct iscsi_cmd *cmd = &isert_cmd->iscsi_cmd;
+        struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
 
         if (cmd->i_state == ISTATE_SEND_TASKMGTRSP ||
             cmd->i_state == ISTATE_SEND_LOGOUTRSP ||
@@ -1625,8 +1611,7 @@ isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
 static int
 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
 {
-        struct isert_cmd *isert_cmd = container_of(cmd,
-                                        struct isert_cmd, iscsi_cmd);
+        struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
         struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)
@@ -1675,8 +1660,7 @@ static int
 isert_put_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
                 bool nopout_response)
 {
-        struct isert_cmd *isert_cmd = container_of(cmd,
-                                struct isert_cmd, iscsi_cmd);
+        struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
 
@@ -1695,8 +1679,7 @@ isert_put_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
 static int
 isert_put_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
 {
-        struct isert_cmd *isert_cmd = container_of(cmd,
-                                struct isert_cmd, iscsi_cmd);
+        struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
 
@@ -1714,8 +1697,7 @@ isert_put_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
 static int
 isert_put_tm_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
 {
-        struct isert_cmd *isert_cmd = container_of(cmd,
-                                struct isert_cmd, iscsi_cmd);
+        struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
 
@@ -1733,8 +1715,7 @@ isert_put_tm_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
 static int
 isert_put_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
 {
-        struct isert_cmd *isert_cmd = container_of(cmd,
-                                struct isert_cmd, iscsi_cmd);
+        struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
         struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
@@ -1766,8 +1747,7 @@ isert_put_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
 static int
 isert_put_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
 {
-        struct isert_cmd *isert_cmd = container_of(cmd,
-                                struct isert_cmd, iscsi_cmd);
+        struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
         struct iscsi_text_rsp *hdr =
@@ -1809,7 +1789,7 @@ isert_build_rdma_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
                     struct ib_sge *ib_sge, struct ib_send_wr *send_wr,
                     u32 data_left, u32 offset)
 {
-        struct iscsi_cmd *cmd = &isert_cmd->iscsi_cmd;
+        struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
         struct scatterlist *sg_start, *tmp_sg;
         struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
         u32 sg_off, page_off;
@@ -1854,8 +1834,7 @@ static int
 isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
 {
         struct se_cmd *se_cmd = &cmd->se_cmd;
-        struct isert_cmd *isert_cmd = container_of(cmd,
-                                        struct isert_cmd, iscsi_cmd);
+        struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
         struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct ib_send_wr *wr_failed, *send_wr;
@@ -1958,8 +1937,7 @@ static int
 isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
 {
         struct se_cmd *se_cmd = &cmd->se_cmd;
-        struct isert_cmd *isert_cmd = container_of(cmd,
-                                        struct isert_cmd, iscsi_cmd);
+        struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
         struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
         struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
         struct ib_send_wr *wr_failed, *send_wr;
@@ -2405,12 +2383,12 @@ static void isert_free_conn(struct iscsi_conn *conn)
 static struct iscsit_transport iser_target_transport = {
         .name                   = "IB/iSER",
         .transport_type         = ISCSI_INFINIBAND,
+        .priv_size              = sizeof(struct isert_cmd),
         .owner                  = THIS_MODULE,
         .iscsit_setup_np        = isert_setup_np,
         .iscsit_accept_np       = isert_accept_np,
         .iscsit_free_np         = isert_free_np,
         .iscsit_free_conn       = isert_free_conn,
-        .iscsit_alloc_cmd       = isert_alloc_cmd,
         .iscsit_get_login_rx    = isert_get_login_rx,
         .iscsit_put_login_tx    = isert_put_login_tx,
         .iscsit_immediate_queue = isert_immediate_queue,
@@ -2437,21 +2415,10 @@ static int __init isert_init(void)
                 goto destroy_rx_wq;
         }
 
-        isert_cmd_cache = kmem_cache_create("isert_cmd_cache",
-                        sizeof(struct isert_cmd), __alignof__(struct isert_cmd),
-                        0, NULL);
-        if (!isert_cmd_cache) {
-                pr_err("Unable to create isert_cmd_cache\n");
-                ret = -ENOMEM;
-                goto destroy_tx_cq;
-        }
-
         iscsit_register_transport(&iser_target_transport);
         pr_debug("iSER_TARGET[0] - Loaded iser_target_transport\n");
         return 0;
 
-destroy_tx_cq:
-        destroy_workqueue(isert_comp_wq);
 destroy_rx_wq:
         destroy_workqueue(isert_rx_wq);
         return ret;
@@ -2459,7 +2426,6 @@ destroy_rx_wq:
 
 static void __exit isert_exit(void)
 {
-        kmem_cache_destroy(isert_cmd_cache);
         destroy_workqueue(isert_comp_wq);
         destroy_workqueue(isert_rx_wq);
         iscsit_unregister_transport(&iser_target_transport);
diff --git a/drivers/infiniband/ulp/isert/ib_isert.h b/drivers/infiniband/ulp/isert/ib_isert.h
index 191117b5b508..0d45945201cb 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.h
+++ b/drivers/infiniband/ulp/isert/ib_isert.h
@@ -67,7 +67,7 @@ struct isert_cmd {
         u32                     write_va_off;
         u32                     rdma_wr_num;
         struct isert_conn       *conn;
-        struct iscsi_cmd        iscsi_cmd;
+        struct iscsi_cmd        *iscsi_cmd;
         struct ib_sge           *ib_sge;
         struct iser_tx_desc     tx_desc;
         struct isert_rdma_wr    rdma_wr;