Re: [RFC PATCH v1 4/4] ufs: mcq: Added ufshcd_mcq_abort()

Stanley Chu
2023-03-09T03:10:39Z

Hi Bao,

On Wed, Mar 8, 2023 at 12:10 PM Bao D. Nguyen <quic_nguyenb@quicinc.com> wrote:
>
> 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
>

It seems that ufshcd_abort_all() also needs an error handling flow for MCQ.

Thanks,
Stanley