From:   "Bao D. Nguyen" <quic_nguyenb@quicinc.com>
To:     <quic_asutoshd@quicinc.com>, <quic_cang@quicinc.com>,
        <bvanassche@acm.org>, <mani@kernel.org>,
        <stanley.chu@mediatek.com>, <adrian.hunter@intel.com>,
        <beanhuo@micron.com>, <avri.altman@wdc.com>,
        <martin.petersen@oracle.com>
CC:     <linux-scsi@vger.kernel.org>,
        "Bao D. Nguyen" <quic_nguyenb@quicinc.com>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        Arthur Simchaev <Arthur.Simchaev@wdc.com>,
        open list <linux-kernel@vger.kernel.org>
Subject: [RFC PATCH v1 4/4] ufs: mcq: Added ufshcd_mcq_abort()
Date:   Tue, 7 Mar 2023 20:01:44 -0800
Message-ID: <c7fcbb70f0e74d225c1a09f107ba1058270739be.1678247309.git.quic_nguyenb@quicinc.com>
In-Reply-To: <cover.1678247309.git.quic_nguyenb@quicinc.com>
References: <cover.1678247309.git.quic_nguyenb@quicinc.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

Add ufshcd_mcq_abort() to support ufs abort in mcq mode.

Signed-off-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>
---
 drivers/ufs/core/ufs-mcq.c     | 76 ++++++++++++++++++++++++++++++++++++++++++
 drivers/ufs/core/ufshcd-priv.h |  5 ++-
 drivers/ufs/core/ufshcd.c      | 11 ++++--
 3 files changed, 88 insertions(+), 4 deletions(-)

diff --git a/drivers/ufs/core/ufs-mcq.c b/drivers/ufs/core/ufs-mcq.c
index e27d8eb..6c65cd5 100644
--- a/drivers/ufs/core/ufs-mcq.c
+++ b/drivers/ufs/core/ufs-mcq.c
@@ -646,3 +646,79 @@ static bool ufshcd_mcq_cqe_search(struct ufs_hba *hba,
 	spin_unlock(&hwq->cq_lock);
 	return ret;
 }
+
+/**
+ * ufshcd_mcq_abort - Abort the command in MCQ.
+ * @cmd - The command to be aborted.
+ *
+ * Returns SUCCESS or FAILED error codes
+ */
+int ufshcd_mcq_abort(struct scsi_cmnd *cmd)
+{
+	struct Scsi_Host *host = cmd->device->host;
+	struct ufs_hba *hba = shost_priv(host);
+	int tag = scsi_cmd_to_rq(cmd)->tag;
+	struct ufshcd_lrb *lrbp = &hba->lrb[tag];
+	struct ufs_hw_queue *hwq;
+	int err = FAILED;
+
+	if (!lrbp->cmd) {
+		dev_err(hba->dev,
+			"%s: skip abort. cmd at tag %d already completed.\n",
+			__func__, tag);
+		goto out;
+	}
+
+	/* Skip task abort in case previous aborts failed and report failure */
+	if (lrbp->req_abort_skip) {
+		dev_err(hba->dev, "%s: skip abort. tag %d failed earlier\n",
+			__func__, tag);
+		goto out;
+	}
+
+	hwq = ufshcd_mcq_req_to_hwq(hba, scsi_cmd_to_rq(cmd));
+
+	if (ufshcd_mcq_sqe_search(hba, hwq, tag)) {
+		/*
+		 * Failure. The command should not be "stuck" in SQ for
+		 * a long time which resulted in command being aborted.
+		 */
+		dev_err(hba->dev, "%s: cmd found in sq. hwq=%d, tag=%d\n",
+				__func__, hwq->id, tag);
+		/* Set the Command Type to 0xF per the spec */
+		ufshcd_mcq_nullify_cmd(hba, hwq);
+		goto out;
+	}
+
+	if (ufshcd_mcq_cqe_search(hba, hwq, tag)) {
+		dev_err(hba->dev, "%s: cmd found in cq. hwq=%d, tag=%d\n",
+				__func__, hwq->id, tag);
+		/*
+		 * The command should not be 'stuck' in the CQ for such a long time.
+		 * Is interrupt missing? Process the CQEs here. If the interrupt is
+		 * invoked at a later time, the CQ will be empty because the CQEs
+		 * are already processed here.
+		 */
+		ufshcd_mcq_poll_cqe_lock(hba, hwq);
+		err = SUCCESS;
+		goto out;
+	}
+
+	/*
+	 * The command is not in the Submission Queue, and it is not
+	 * in the Completion Queue either. Query the device to see if
+	 * the command is being processed in the device.
+	 */
+	if (ufshcd_try_to_abort_task(hba, tag)) {
+		dev_err(hba->dev, "%s: device abort failed %d\n", __func__, err);
+		lrbp->req_abort_skip = true;
+		goto out;
+	}
+
+	err = SUCCESS;
+	if (lrbp->cmd)
+		ufshcd_release_scsi_cmd(hba, lrbp);
+
+out:
+	return err;
+}
diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index 0527926..d883c03 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -77,7 +77,10 @@ unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 				       struct ufs_hw_queue *hwq);
 
 int ufshcd_mcq_sq_cleanup(struct ufs_hba *hba, int task_tag, int *result);
-
+int ufshcd_mcq_abort(struct scsi_cmnd *cmd);
+int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag);
+void ufshcd_release_scsi_cmd(struct ufs_hba *hba,
+				struct ufshcd_lrb *lrbp);
 #define UFSHCD_MCQ_IO_QUEUE_OFFSET	1
 #define SD_ASCII_STD true
 #define SD_RAW false
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 408c16c..e06399e 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -302,7 +302,6 @@ static int ufshcd_setup_hba_vreg(struct ufs_hba *hba, bool on);
 static int ufshcd_setup_vreg(struct ufs_hba *hba, bool on);
 static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
 					 struct ufs_vreg *vreg);
-static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag);
 static void ufshcd_wb_toggle_buf_flush_during_h8(struct ufs_hba *hba,
 						 bool enable);
 static void ufshcd_hba_vreg_set_lpm(struct ufs_hba *hba);
@@ -5414,7 +5413,7 @@ static irqreturn_t ufshcd_uic_cmd_compl(struct ufs_hba *hba, u32 intr_status)
 }
 
 /* Release the resources allocated for processing a SCSI command. */
-static void ufshcd_release_scsi_cmd(struct ufs_hba *hba,
+void ufshcd_release_scsi_cmd(struct ufs_hba *hba,
 				    struct ufshcd_lrb *lrbp)
 {
 	struct scsi_cmnd *cmd = lrbp->cmd;
@@ -7340,7 +7339,7 @@ static void ufshcd_set_req_abort_skip(struct ufs_hba *hba, unsigned long bitmap)
  *
  * Returns zero on success, non-zero on failure
  */
-static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag)
+int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag)
 {
 	struct ufshcd_lrb *lrbp = &hba->lrb[tag];
 	int err = 0;
@@ -7500,6 +7499,12 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 		goto release;
 	}
 
+	if (is_mcq_enabled(hba)) {
+		/* MCQ mode. Branch off to handle abort for mcq mode */
+		err = ufshcd_mcq_abort(cmd);
+		goto release;
+	}
+
 	/* Skip task abort in case previous aborts failed and report failure */
 	if (lrbp->req_abort_skip) {
 		dev_err(hba->dev, "%s: skipping abort\n", __func__);
-- 
2.7.4