Re: [PATCH v1 1/2] scsi: ufs: Abort tasks before clear them from doorbell

Can Guo
2020-08-31T01:20:44Z

Hi Bean,

On 2020-08-31 02:11, Bean Huo wrote:
> Hi Can
> This patch conflicts and be not in line with this series patches : h
> ttps://patchwork.kernel.org/cover/11709279/, which has been applied
> into 5.9/scsi-fixes. But they are not apppiled in the 5.9/scsi-queue.
>
> Maybe you should rebase your patch from scsi-fixes branch. or do you
> have another better option?
>
> Thanks,
> Bean
>

I am pushing this change due to LINERSET handling needs it and LINERESET
handling is added based on my previous changes to err_handler, which are
picked by 5.10/scsi-queue. So the two are applied for 5.10/scsi-queue
only.
Any conflicts you see on 5.10/scsi-queue?

Thanks,

Can Guo.

> On Mon, 2020-08-24 at 19:07 -0700, Can Guo wrote:
>> To recovery non-fatal errors, no full reset is required, err_handler
>> only
>> clears those pending TRs/TMRs so that scsi layer can re-issue them.
>> In
>> current err_handler, TRs are directly cleared from UFS host's
>> doorbell but
>> not aborted from device side. However, according to the UFSHCI JEDEC
>> spec,
>> the host software shall use UTP Transfer Request List CLear Register
>> to
>> clear a task from UFS host's doorbell only when a UTP Transfer
>> Request is
>> expected to not be completed, e.g. when the host software receives a
>> “FUNCTION COMPLETE” Task Management response which means a Transfer
>> Request
>> was aborted. To follow the UFSHCI JEDEC spec, in err_handler, aborts
>> one TR
>> before clearing it from doorbell.
>>
>> Signed-off-by: Can Guo <cang@codeaurora.org>
>> ---
>> drivers/scsi/ufs/ufshcd.c | 143 ++++++++++++++++++++++++++--------
>> ------------
>> 1 file changed, 81 insertions(+), 62 deletions(-)
>>
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index b8441ad..000895f 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -235,6 +235,7 @@ 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 int ufshcd_wb_buf_flush_enable(struct ufs_hba *hba);
>> static int ufshcd_wb_buf_flush_disable(struct ufs_hba *hba);
>> static int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable);
>> @@ -5657,8 +5658,8 @@ static void ufshcd_err_handler(struct
>> work_struct *work)
>> {
>> struct ufs_hba *hba;
>> unsigned long flags;
>> - u32 err_xfer = 0;
>> - u32 err_tm = 0;
>> + bool err_xfer = false;
>> + bool err_tm = false;
>> int err = 0;
>> int tag;
>> bool needs_reset = false;
>> @@ -5734,7 +5735,7 @@ static void ufshcd_err_handler(struct
>> work_struct *work)
>> spin_unlock_irqrestore(hba->host->host_lock, flags);
>> /* Clear pending transfer requests */
>> for_each_set_bit(tag, &hba->outstanding_reqs, hba->nutrs) {
>> - if (ufshcd_clear_cmd(hba, tag)) {
>> + if (ufshcd_try_to_abort_task(hba, tag)) {
>> err_xfer = true;
>> goto lock_skip_pending_xfer_clear;
>> }
>> @@ -6486,7 +6487,7 @@ static void ufshcd_set_req_abort_skip(struct
>> ufs_hba *hba, unsigned long bitmap)
>> }
>>
>> /**
>> - * ufshcd_abort - abort a specific command
>> + * ufshcd_try_to_abort_task - abort a specific task
>> * @cmd: SCSI command pointer
>> *
>> * Abort the pending command in device by sending UFS_ABORT_TASK
>> task management
>> @@ -6495,6 +6496,80 @@ static void ufshcd_set_req_abort_skip(struct
>> ufs_hba *hba, unsigned long bitmap)
>> * issued. To avoid that, first issue UFS_QUERY_TASK to check if the
>> command is
>> * really issued and then try to abort it.
>> *
>> + * Returns zero on success, non-zero on failure
>> + */
>> +static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag)
>> +{
>> + struct ufshcd_lrb *lrbp = &hba->lrb[tag];
>> + int err = 0;
>> + int poll_cnt;
>> + u8 resp = 0xF;
>> + u32 reg;
>> +
>> + for (poll_cnt = 100; poll_cnt; poll_cnt--) {
>> + err = ufshcd_issue_tm_cmd(hba, lrbp->lun, lrbp-
>> >task_tag,
>> + UFS_QUERY_TASK, &resp);
>> + if (!err && resp ==
>> UPIU_TASK_MANAGEMENT_FUNC_SUCCEEDED) {
>> + /* cmd pending in the device */
>> + dev_err(hba->dev, "%s: cmd pending in the
>> device. tag = %d\n",
>> + __func__, tag);
>> + break;
>> + } else if (!err && resp ==
>> UPIU_TASK_MANAGEMENT_FUNC_COMPL) {
>> + /*
>> + * cmd not pending in the device, check if it
>> is
>> + * in transition.
>> + */
>> + dev_err(hba->dev, "%s: cmd at tag %d not
>> pending in the device.\n",
>> + __func__, tag);
>> + reg = ufshcd_readl(hba,
>> REG_UTP_TRANSFER_REQ_DOOR_BELL);
>> + if (reg & (1 << tag)) {
>> + /* sleep for max. 200us to stabilize */
>> + usleep_range(100, 200);
>> + continue;
>> + }
>> + /* command completed already */
>> + dev_err(hba->dev, "%s: cmd at tag %d
>> successfully cleared from DB.\n",
>> + __func__, tag);
>> + goto out;
>> + } else {
>> + dev_err(hba->dev,
>> + "%s: no response from device. tag = %d,
>> err %d\n",
>> + __func__, tag, err);
>> + if (!err)
>> + err = resp; /* service response error
>> */
>> + goto out;
>> + }
>> + }
>> +
>> + if (!poll_cnt) {
>> + err = -EBUSY;
>> + goto out;
>> + }
>> +
>> + err = ufshcd_issue_tm_cmd(hba, lrbp->lun, lrbp->task_tag,
>> + UFS_ABORT_TASK, &resp);
>> + if (err || resp != UPIU_TASK_MANAGEMENT_FUNC_COMPL) {
>> + if (!err) {
>> + err = resp; /* service response error */
>> + dev_err(hba->dev, "%s: issued. tag = %d, err
>> %d\n",
>> + __func__, tag, err);
>> + }
>> + goto out;
>> + }
>> +
>> + err = ufshcd_clear_cmd(hba, tag);
>> + if (err)
>> + dev_err(hba->dev, "%s: Failed clearing cmd at tag %d,
>> err %d\n",
>> + __func__, tag, err);
>> +
>> +out:
>> + return err;
>> +}
>> +
>> +/**
>> + * ufshcd_abort - scsi host template eh_abort_handler callback
>> + * @cmd: SCSI command pointer
>> + *
>> * Returns SUCCESS/FAILED
>> */
>> static int ufshcd_abort(struct scsi_cmnd *cmd)
>> @@ -6504,8 +6579,6 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
>> unsigned long flags;
>> unsigned int tag;
>> int err = 0;
>> - int poll_cnt;
>> - u8 resp = 0xF;
>> struct ufshcd_lrb *lrbp;
>> u32 reg;
>>
>> @@ -6574,63 +6647,9 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
>> 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);
>> - if (!err && resp ==
>> UPIU_TASK_MANAGEMENT_FUNC_SUCCEEDED) {
>> - /* cmd pending in the device */
>> - dev_err(hba->dev, "%s: cmd pending in the
>> device. tag = %d\n",
>> - __func__, tag);
>> - break;
>> - } else if (!err && resp ==
>> UPIU_TASK_MANAGEMENT_FUNC_COMPL) {
>> - /*
>> - * cmd not pending in the device, check if it
>> is
>> - * in transition.
>> - */
>> - dev_err(hba->dev, "%s: cmd at tag %d not
>> pending in the device.\n",
>> - __func__, tag);
>> - reg = ufshcd_readl(hba,
>> REG_UTP_TRANSFER_REQ_DOOR_BELL);
>> - if (reg & (1 << tag)) {
>> - /* sleep for max. 200us to stabilize */
>> - usleep_range(100, 200);
>> - continue;
>> - }
>> - /* command completed already */
>> - dev_err(hba->dev, "%s: cmd at tag %d
>> successfully cleared from DB.\n",
>> - __func__, tag);
>> - goto out;
>> - } else {
>> - dev_err(hba->dev,
>> - "%s: no response from device. tag = %d,
>> err %d\n",
>> - __func__, tag, err);
>> - if (!err)
>> - err = resp; /* service response error
>> */
>> - goto out;
>> - }
>> - }
>> -
>> - if (!poll_cnt) {
>> - err = -EBUSY;
>> - goto out;
>> - }
>> -
>> - err = ufshcd_issue_tm_cmd(hba, lrbp->lun, lrbp->task_tag,
>> - UFS_ABORT_TASK, &resp);
>> - if (err || resp != UPIU_TASK_MANAGEMENT_FUNC_COMPL) {
>> - if (!err) {
>> - err = resp; /* service response error */
>> - dev_err(hba->dev, "%s: issued. tag = %d, err
>> %d\n",
>> - __func__, tag, err);
>> - }
>> - goto out;
>> - }
>> -
>> - err = ufshcd_clear_cmd(hba, tag);
>> - if (err) {
>> - dev_err(hba->dev, "%s: Failed clearing cmd at tag %d,
>> err %d\n",
>> - __func__, tag, err);
>> + err = ufshcd_try_to_abort_task(hba, tag);
>> + if (err)
>> goto out;
>> - }
>>
>> spin_lock_irqsave(host->host_lock, flags);
>> __ufshcd_transfer_req_compl(hba, (1UL << tag));