scsi: ufs: skip request abort task when previous aborts failed

On certain error conditions request abort task itself might fail
when aborting a request. In such case, subsequent request aborts
should skip issuing the abort task as it is expected to fail as well,
and device reset handler will be called next.

Change-Id: I28c111c58e8c7fd54b836c6933d5fc56682c28b9
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>

drivers/scsi/ufs/ufshcd.c

@@ -2391,6 +2391,7 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 	lrbp->lun = ufshcd_scsi_to_upiu_lun(cmd->device->lun);
 	lrbp->intr_cmd = !ufshcd_is_intr_aggr_allowed(hba) ? true : false;
 	lrbp->command_type = UTP_CMD_TYPE_SCSI;
+	lrbp->req_abort_skip = false;
 
 	/* form UPIU before issuing the command */
 	ufshcd_compose_upiu(hba, lrbp);
@@ -5578,6 +5579,17 @@ out:
 	return err;
 }
 
+static void ufshcd_set_req_abort_skip(struct ufs_hba *hba, unsigned long bitmap)
+{
+	struct ufshcd_lrb *lrbp;
+	int tag;
+
+	for_each_set_bit(tag, &bitmap, hba->nutrs) {
+		lrbp = &hba->lrb[tag];
+		lrbp->req_abort_skip = true;
+	}
+}
+
 /**
  * ufshcd_abort - abort a specific command
  * @cmd: SCSI command pointer
@@ -5620,11 +5632,15 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 		return ufshcd_eh_host_reset_handler(cmd);
 
 	ufshcd_hold_all(hba);
-	/* If command is already aborted/completed, return SUCCESS */
-	if (!(test_bit(tag, &hba->outstanding_reqs)))
-		goto out;
-
 	reg = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
+	/* If command is already aborted/completed, return SUCCESS */
+	if (!(test_bit(tag, &hba->outstanding_reqs))) {
+		dev_err(hba->dev,
+			"%s: cmd already completed, outstanding=0x%lx, doorbell=0x%x\n",
+			__func__, hba->outstanding_reqs, reg);
+		goto out;
+	}
+
 	if (!(reg & (1 << tag))) {
 		dev_err(hba->dev,
 		"%s: cmd was completed, but without a notifying intr, tag = %d",
@@ -5638,6 +5654,13 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 	ufshcd_print_pwr_info(hba);
 	ufshcd_print_trs(hba, 1 << tag, true);
 
+
+	/* Skip task abort in case previous aborts failed and report failure */
+	if (lrbp->req_abort_skip) {
+		err = -EIO;
+		goto out;
+	}
+
 	for (poll_cnt = 100; poll_cnt; poll_cnt--) {
 		err = ufshcd_issue_tm_cmd(hba, lrbp->lun, lrbp->task_tag,
 				UFS_QUERY_TASK, &resp);
@@ -5711,6 +5734,7 @@ out:
 		err = SUCCESS;
 	} else {
 		dev_err(hba->dev, "%s: failed with err %d\n", __func__, err);
+		ufshcd_set_req_abort_skip(hba, hba->outstanding_reqs);
 		err = FAILED;
 	}
 

include/linux/scsi/ufs/ufshcd.h

@@ -184,6 +184,7 @@ struct ufs_pm_lvl_states {
  * @lun: LUN of the command
  * @intr_cmd: Interrupt command (doesn't participate in interrupt aggregation)
  * @issue_time_stamp: time stamp for debug purposes
+ * @req_abort_skip: skip request abort task flag
  */
 struct ufshcd_lrb {
 	struct utp_transfer_req_desc *utr_descriptor_ptr;
@@ -206,6 +207,8 @@ struct ufshcd_lrb {
 	u8 lun; /* UPIU LUN id field is only 8-bit wide */
 	bool intr_cmd;
 	ktime_t issue_time_stamp;
+
+	bool req_abort_skip;
 };
 
 /**