scsi: ufs: Minor adjustments to error handling

In error handling prepare stage, after SCSI requests are blocked, do a
down/up_write(clk_scaling_lock) to clean up the queuecommand() path.
Meanwhile, stop eeh_work in case it disturbs error recovery. Moreover,
reset ufshcd_state at the entrance of ufshcd_probe_hba(), since it may be
called multiple times during error recovery.

Link: https://lore.kernel.org/r/1614145010-36079-2-git-send-email-cang@codeaurora.org
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 7716175..607fdfa 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4987,6 +4987,7 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
                         * UFS device needs urgent BKOPs.
                         */
                        if (!hba->pm_op_in_progress &&
+                           !ufshcd_eh_in_progress(hba) &&
                            ufshcd_is_exception_event(lrbp->ucd_rsp_ptr) &&
                            schedule_work(&hba->eeh_work)) {
                                /*
@@ -5784,13 +5785,20 @@ static void ufshcd_err_handling_prepare(struct ufs_hba *hba)
                        ufshcd_suspend_clkscaling(hba);
                ufshcd_clk_scaling_allow(hba, false);
        }
+       ufshcd_scsi_block_requests(hba);
+       /* Drain ufshcd_queuecommand() */
+       down_write(&hba->clk_scaling_lock);
+       up_write(&hba->clk_scaling_lock);
+       cancel_work_sync(&hba->eeh_work);
 }
 
 static void ufshcd_err_handling_unprepare(struct ufs_hba *hba)
 {
+       ufshcd_scsi_unblock_requests(hba);
        ufshcd_release(hba);
        if (ufshcd_is_clkscaling_supported(hba))
                ufshcd_clk_scaling_suspend(hba, false);
+       ufshcd_clear_ua_wluns(hba);
        pm_runtime_put(hba->dev);
 }
 
@@ -5882,8 +5890,8 @@ static void ufshcd_err_handler(struct work_struct *work)
        spin_unlock_irqrestore(hba->host->host_lock, flags);
        ufshcd_err_handling_prepare(hba);
        spin_lock_irqsave(hba->host->host_lock, flags);
-       ufshcd_scsi_block_requests(hba);
-       hba->ufshcd_state = UFSHCD_STATE_RESET;
+       if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
+               hba->ufshcd_state = UFSHCD_STATE_RESET;
 
        /* Complete requests that have door-bell cleared by h/w */
        ufshcd_complete_requests(hba);
@@ -6042,12 +6050,8 @@ skip_err_handling:
        }
        ufshcd_clear_eh_in_progress(hba);
        spin_unlock_irqrestore(hba->host->host_lock, flags);
-       ufshcd_scsi_unblock_requests(hba);
        ufshcd_err_handling_unprepare(hba);
        up(&hba->host_sem);
-
-       if (!err && needs_reset)
-               ufshcd_clear_ua_wluns(hba);
 }
 
 /**
@@ -7858,6 +7862,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool async)
        unsigned long flags;
        ktime_t start = ktime_get();
 
+       hba->ufshcd_state = UFSHCD_STATE_RESET;
+
        ret = ufshcd_link_startup(hba);
        if (ret)
                goto out;