scsi: ufs: core: Fix handling of lrbp->cmd

ufshcd_queuecommand() may be called two times in a row for a SCSI command
before it is completed. Hence make the following changes:

 - In the functions that submit a command, do not check the old value of
   lrbp->cmd nor clear lrbp->cmd in error paths.

 - In ufshcd_release_scsi_cmd(), do not clear lrbp->cmd.

See also scsi_send_eh_cmnd().

This commit prevents that the following appears if a command times out:

WARNING: at drivers/ufs/core/ufshcd.c:2965 ufshcd_queuecommand+0x6f8/0x9a8
Call trace:
 ufshcd_queuecommand+0x6f8/0x9a8
 scsi_send_eh_cmnd+0x2c0/0x960
 scsi_eh_test_devices+0x100/0x314
 scsi_eh_ready_devs+0xd90/0x114c
 scsi_error_handler+0x2b4/0xb70
 kthread+0x16c/0x1e0

Fixes: 5a0b0cb9bee7 ("[SCSI] ufs: Add support for sending NOP OUT UPIU")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230524203659.1394307-3-bvanassche@acm.org
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index ff92e53835dfce1cde7739b1aa834d4d088adc68..55c58bfd7f5d4192c856b58f3dafd52139ef27ef 100644 (file)
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -2945,7 +2945,6 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
                (hba->clk_gating.state != CLKS_ON));
 
        lrbp = &hba->lrb[tag];
-       WARN_ON(lrbp->cmd);
        lrbp->cmd = cmd;
        lrbp->task_tag = tag;
        lrbp->lun = ufshcd_scsi_to_upiu_lun(cmd->device->lun);
@@ -2961,7 +2960,6 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 
        err = ufshcd_map_sg(hba, lrbp);
        if (err) {
-               lrbp->cmd = NULL;
                ufshcd_release(hba);
                goto out;
        }
@@ -3180,7 +3178,7 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba,
        down_read(&hba->clk_scaling_lock);
 
        lrbp = &hba->lrb[tag];
-       WARN_ON(lrbp->cmd);
+       lrbp->cmd = NULL;
        err = ufshcd_compose_dev_cmd(hba, lrbp, cmd_type, tag);
        if (unlikely(err))
                goto out;
@@ -5422,7 +5420,6 @@ static void ufshcd_release_scsi_cmd(struct ufs_hba *hba,
        struct scsi_cmnd *cmd = lrbp->cmd;
 
        scsi_dma_unmap(cmd);
-       lrbp->cmd = NULL;       /* Mark the command as completed. */
        ufshcd_release(hba);
        ufshcd_clk_scaling_update_busy(hba);
 }
@@ -7037,7 +7034,6 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba,
        down_read(&hba->clk_scaling_lock);
 
        lrbp = &hba->lrb[tag];
-       WARN_ON(lrbp->cmd);
        lrbp->cmd = NULL;
        lrbp->task_tag = tag;
        lrbp->lun = 0;
@@ -7209,7 +7205,6 @@ int ufshcd_advanced_rpmb_req_handler(struct ufs_hba *hba, struct utp_upiu_req *r
        down_read(&hba->clk_scaling_lock);
 
        lrbp = &hba->lrb[tag];
-       WARN_ON(lrbp->cmd);
        lrbp->cmd = NULL;
        lrbp->task_tag = tag;
        lrbp->lun = UFS_UPIU_RPMB_WLUN;