scsi: target: tcmu: Use priv pointer in se_cmd

We initialize and clean up the se_cmd's priv pointer under cmd_ring_lock to
point to the corresponding tcmu_cmd.

In the patch that implements tmr_notify callback in tcmu we will use the
priv pointer.

Link: https://lore.kernel.org/r/20200726153510.13077-4-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index 366878b..b06b18d 100644 (file)
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -541,6 +541,8 @@ tcmu_get_block_page(struct tcmu_dev *udev, uint32_t dbi)
 
 static inline void tcmu_free_cmd(struct tcmu_cmd *tcmu_cmd)
 {
+       if (tcmu_cmd->se_cmd)
+               tcmu_cmd->se_cmd->priv = NULL;
        kfree(tcmu_cmd->dbi);
        kmem_cache_free(tcmu_cmd_cache, tcmu_cmd);
 }
@@ -1109,10 +1111,11 @@ tcmu_queue_cmd(struct se_cmd *se_cmd)
                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 
        mutex_lock(&udev->cmdr_lock);
+       se_cmd->priv = tcmu_cmd;
        ret = queue_cmd_ring(tcmu_cmd, &scsi_ret);
-       mutex_unlock(&udev->cmdr_lock);
        if (ret < 0)
                tcmu_free_cmd(tcmu_cmd);
+       mutex_unlock(&udev->cmdr_lock);
        return scsi_ret;
 }
 
@@ -1179,7 +1182,6 @@ done:
                target_complete_cmd(cmd->se_cmd, entry->rsp.scsi_status);
 
 out:
-       cmd->se_cmd = NULL;
        tcmu_cmd_free_data(cmd, cmd->dbi_cnt);
        tcmu_free_cmd(cmd);
 }
@@ -1285,6 +1287,7 @@ static void tcmu_check_expired_ring_cmd(struct tcmu_cmd *cmd)
        set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags);
        list_del_init(&cmd->queue_entry);
        se_cmd = cmd->se_cmd;
+       se_cmd->priv = NULL;
        cmd->se_cmd = NULL;
 
        pr_debug("Timing out inflight cmd %u on dev %s.\n",