tcm_loop: kill tcm_loop_allocate_core_cmd

This function makes little sense as a separate abstraction as it's deeply
interwinded with the control flow of its only caller.  Merged it into
tcm_loop_queuecommand after factoring out a helper to convert the task
attribute representation.

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

diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c
index 7cfbcb00b3c308369e1523e011885c5978f42bd3..b1edc517f4e3bb0e7bdac148dcbfd4355d9ff038 100644 (file)
--- a/drivers/target/loopback/tcm_loop.c
+++ b/drivers/target/loopback/tcm_loop.c
@@ -48,81 +48,6 @@ static struct kmem_cache *tcm_loop_cmd_cache;
 
 static int tcm_loop_hba_no_cnt;
 
-/*
- * Allocate a tcm_loop cmd descriptor from target_core_mod code
- *
- * Can be called from interrupt context in tcm_loop_queuecommand() below
- */
-static struct se_cmd *tcm_loop_allocate_core_cmd(
-       struct tcm_loop_hba *tl_hba,
-       struct se_portal_group *se_tpg,
-       struct scsi_cmnd *sc)
-{
-       struct se_cmd *se_cmd;
-       struct se_session *se_sess;
-       struct tcm_loop_nexus *tl_nexus = tl_hba->tl_nexus;
-       struct tcm_loop_cmd *tl_cmd;
-       int sam_task_attr;
-
-       if (!tl_nexus) {
-               scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
-                               " does not exist\n");
-               set_host_byte(sc, DID_ERROR);
-               return NULL;
-       }
-       se_sess = tl_nexus->se_sess;
-
-       tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
-       if (!tl_cmd) {
-               pr_err("Unable to allocate struct tcm_loop_cmd\n");
-               set_host_byte(sc, DID_ERROR);
-               return NULL;
-       }
-       se_cmd = &tl_cmd->tl_se_cmd;
-       /*
-        * Save the pointer to struct scsi_cmnd *sc
-        */
-       tl_cmd->sc = sc;
-       /*
-        * Locate the SAM Task Attr from struct scsi_cmnd *
-        */
-       if (sc->device->tagged_supported) {
-               switch (sc->tag) {
-               case HEAD_OF_QUEUE_TAG:
-                       sam_task_attr = MSG_HEAD_TAG;
-                       break;
-               case ORDERED_QUEUE_TAG:
-                       sam_task_attr = MSG_ORDERED_TAG;
-                       break;
-               default:
-                       sam_task_attr = MSG_SIMPLE_TAG;
-                       break;
-               }
-       } else
-               sam_task_attr = MSG_SIMPLE_TAG;
-
-       /*
-        * Initialize struct se_cmd descriptor from target_core_mod infrastructure
-        */
-       transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
-                       scsi_bufflen(sc), sc->sc_data_direction, sam_task_attr,
-                       &tl_cmd->tl_sense_buf[0]);
-
-       if (scsi_bidi_cmnd(sc))
-               se_cmd->se_cmd_flags |= SCF_BIDI;
-
-       /*
-        * Locate the struct se_lun pointer and attach it to struct se_cmd
-        */
-       if (transport_lookup_cmd_lun(se_cmd, tl_cmd->sc->device->lun) < 0) {
-               kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
-               set_host_byte(sc, DID_NO_CONNECT);
-               return NULL;
-       }
-
-       return se_cmd;
-}
-
 /*
  * Called by struct target_core_fabric_ops->new_cmd_map()
  *
@@ -262,6 +187,25 @@ static int tcm_loop_change_queue_depth(
        return sdev->queue_depth;
 }
 
+/*
+ * Locate the SAM Task Attr from struct scsi_cmnd *
+ */
+static int tcm_loop_sam_attr(struct scsi_cmnd *sc)
+{
+       if (sc->device->tagged_supported) {
+               switch (sc->tag) {
+               case HEAD_OF_QUEUE_TAG:
+                       return MSG_HEAD_TAG;
+               case ORDERED_QUEUE_TAG:
+                       return MSG_ORDERED_TAG;
+               default:
+                       break;
+               }
+       }
+
+       return MSG_SIMPLE_TAG;
+}
+
 /*
  * Main entry point from struct scsi_host_template for incoming SCSI CDB+Data
  * from Linux/SCSI subsystem for SCSI low level device drivers (LLDs)
@@ -274,6 +218,10 @@ static int tcm_loop_queuecommand(
        struct se_portal_group *se_tpg;
        struct tcm_loop_hba *tl_hba;
        struct tcm_loop_tpg *tl_tpg;
+       struct se_session *se_sess;
+       struct tcm_loop_nexus *tl_nexus;
+       struct tcm_loop_cmd *tl_cmd;
+
 
        pr_debug("tcm_loop_queuecommand() %d:%d:%d:%d got CDB: 0x%02x"
                " scsi_buf_len: %u\n", sc->device->host->host_no,
@@ -290,24 +238,47 @@ static int tcm_loop_queuecommand(
         */
        if (!tl_tpg->tl_hba) {
                set_host_byte(sc, DID_NO_CONNECT);
-               sc->scsi_done(sc);
-               return 0;
+               goto out_done;
        }
        se_tpg = &tl_tpg->tl_se_tpg;
-       /*
-        * Determine the SAM Task Attribute and allocate tl_cmd and
-        * tl_cmd->tl_se_cmd from TCM infrastructure
-        */
-       se_cmd = tcm_loop_allocate_core_cmd(tl_hba, se_tpg, sc);
-       if (!se_cmd) {
-               sc->scsi_done(sc);
-               return 0;
+
+       tl_nexus = tl_hba->tl_nexus;
+       if (!tl_nexus) {
+               scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
+                               " does not exist\n");
+               set_host_byte(sc, DID_ERROR);
+               goto out_done;
        }
-       /*
-        * Queue up the newly allocated to be processed in TCM thread context.
-       */
+       se_sess = tl_nexus->se_sess;
+
+       tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
+       if (!tl_cmd) {
+               pr_err("Unable to allocate struct tcm_loop_cmd\n");
+               set_host_byte(sc, DID_ERROR);
+               goto out_done;
+       }
+       se_cmd = &tl_cmd->tl_se_cmd;
+       tl_cmd->sc = sc;
+
+       transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
+                       scsi_bufflen(sc), sc->sc_data_direction,
+                       tcm_loop_sam_attr(sc), &tl_cmd->tl_sense_buf[0]);
+
+       if (scsi_bidi_cmnd(sc))
+               se_cmd->se_cmd_flags |= SCF_BIDI;
+
+       if (transport_lookup_cmd_lun(se_cmd, tl_cmd->sc->device->lun) < 0) {
+               kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
+               set_host_byte(sc, DID_NO_CONNECT);
+               goto out_done;
+       }
+
        transport_generic_handle_cdb_map(se_cmd);
        return 0;
+
+out_done:
+       sc->scsi_done(sc);
+       return 0;
 }
 
 /*