RE: [PATCH 2/7] scsi: ufs: find out sense data over scsi status values

[Seungwon Jeon <tgih.jun@samsung.com>]

On Tue, July 30, 2013, Santosh Y wrote:
> On Fri, Jul 26, 2013 at 7:16 PM, Seungwon Jeon <tgih.jun@samsung.com> wrote:
> > Except for 'GOOD' and 'CHECK CONDITION', other status value
> > in Response UPIU may or may contain sense data. If a non-zero
> > value is in the Data Segment Length field, it means that UPIU
> > has Sense Data in the Data Segment area.
> >
> > Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> > ---
> >  drivers/scsi/ufs/ufs.h    |    1 +
> >  drivers/scsi/ufs/ufshcd.c |   27 +++++++++++++++++++--------
> >  2 files changed, 20 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
> > index 139bc06..737c31b 100644
> > --- a/drivers/scsi/ufs/ufs.h
> > +++ b/drivers/scsi/ufs/ufs.h
> > @@ -114,6 +114,7 @@ enum {
> >         MASK_SCSI_STATUS        = 0xFF,
> >         MASK_TASK_RESPONSE      = 0xFF00,
> >         MASK_RSP_UPIU_RESULT    = 0xFFFF,
> > +       MASK_RSP_UPIU_DATA_SEG_LEN      = 0xFFFF,
> >  };
> >
> >  /* Task management service response */
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> > index 4cf3a2d..688ae0e 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -218,6 +218,20 @@ ufshcd_get_rsp_upiu_result(struct utp_upiu_rsp *ucd_rsp_ptr)
> >         return be32_to_cpu(ucd_rsp_ptr->header.dword_1) & MASK_RSP_UPIU_RESULT;
> >  }
> >
> > +/*
> > + * ufshcd_get_rsp_upiu_data_seg_len - Get the data segment length
> > + *                             from response UPIU
> > + * @ucd_rsp_ptr: pointer to response UPIU
> > + *
> > + * Return the data segment length.
> > + */
> > +static inline int
> > +ufshcd_get_rsp_upiu_data_seg_len(struct utp_upiu_rsp *ucd_rsp_ptr)
> > +{
> > +       return be32_to_cpu(ucd_rsp_ptr->header.dword_2) &
> > +               MASK_RSP_UPIU_DATA_SEG_LEN;
> > +}
> > +
> >  /**
> >   * ufshcd_config_int_aggr - Configure interrupt aggregation values.
> >   *             Currently there is no use case where we want to configure
> > @@ -298,7 +312,8 @@ void ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag)
> >  static inline void ufshcd_copy_sense_data(struct ufshcd_lrb *lrbp)
> >  {
> >         int len;
> > -       if (lrbp->sense_buffer) {
> > +       if (lrbp->sense_buffer &&
> > +           !ufshcd_get_rsp_upiu_data_seg_len(lrbp->ucd_rsp_ptr)) {
> >                 len = be16_to_cpu(lrbp->ucd_rsp_ptr->sense_data_len);
> >                 memcpy(lrbp->sense_buffer,
> >                         lrbp->ucd_rsp_ptr->sense_data,
> 
> Also please change the SCSI_SENSE_BUFFERSIZE to 18-bytes as per the
> spec, *in case* if wrong 'data segment length' is returned, there
> won't be a need to memcpy extra bytes ;-).
> 
> #define UFS_SENSE_BUFFERSIZE 18
> memcpy(lrbp->sense_buffer,
> 			lrbp->ucd_rsp_ptr->sense_data,
> 			min_t(int, len, UFS_SENSE_BUFFERSIZE));
Ok. I'll check.
But considering the extension with spec. revision, it's not bad to be kept.
Current: [#define SCSI_SENSE_BUFFERSIZE   96]

Thanks,
Seungwon Jeon

> 
> 
> > @@ -1156,21 +1171,17 @@ ufshcd_scsi_cmd_status(struct ufshcd_lrb *lrbp, int scsi_status)
> >                           SAM_STAT_CHECK_CONDITION;
> >                 ufshcd_copy_sense_data(lrbp);
> >                 break;
> > -       case SAM_STAT_BUSY:
> > -               result |= SAM_STAT_BUSY;
> > -               break;
> >         case SAM_STAT_TASK_SET_FULL:
> > -
> >                 /*
> >                  * If a LUN reports SAM_STAT_TASK_SET_FULL, then the LUN queue
> >                  * depth needs to be adjusted to the exact number of
> >                  * outstanding commands the LUN can handle at any given time.
> >                  */
> >                 ufshcd_adjust_lun_qdepth(lrbp->cmd);
> > -               result |= SAM_STAT_TASK_SET_FULL;
> > -               break;
> > +       case SAM_STAT_BUSY:
> >         case SAM_STAT_TASK_ABORTED:
> > -               result |= SAM_STAT_TASK_ABORTED;
> > +               result |= scsi_status;
> > +               ufshcd_copy_sense_data(lrbp);
> >                 break;
> >         default:
> >                 result |= DID_ERROR << 16;
> > --
> > 1.7.0.4
> >
> >
> 
> 
> 
> --
> ~Santosh
> --
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