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Subject: RE: RE: RE: RE: [PATCH v22 2/4] scsi: ufs: L2P map management for
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Date:   Tue, 23 Feb 2021 17:55:43 +0900
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Precedence: bulk

> > > > +/*
> > > > + * This function will parse recommended active subregion information in
> > > > sense
> > > > + * data field of response UPIU with SAM_STAT_GOOD state.
> > > > + */
> > > > +void ufshpb_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
> > > > +{
> > > > +       struct ufshpb_lu *hpb;
> > > > +       struct scsi_device *sdev;
> > > > +       struct utp_hpb_rsp *rsp_field = &lrbp->ucd_rsp_ptr->hr;
> > > > +       int data_seg_len;
> > > > +       bool found = false;
> > > > +
> > > > +       __shost_for_each_device(sdev, hba->host) {
> > > > +               hpb = ufshpb_get_hpb_data(sdev);
> > > > +
> > > > +               if (!hpb)
> > > > +                       continue;
> > > > +
> > > > +               if (rsp_field->lun == hpb->lun) {
> > > > +                       found = true;
> > > > +                       break;
> > > This piece of code looks awkward, although it is probably working.
> > > Why not just having a reference to the hpb luns, e.g. something like:
> > > struct ufshpb_lu *hpb_luns[8] in struct ufs_hba.
> > > Less elegant - but much more effective than iterating the scsi host on every
> > completion interrupt.
> > 
> > How about checking (cmd->lun == rsp->lun) before the iteration?
> > Major case will be have same lun. And, it is hard to add struct ufshpb_lu
> > *hpb_luns[128]
> > in struct ufs_hba, because LUN can be upto 127.
> Oh - yes, 8 is for write booster.
> OK.  Whatever you think.

Then, I want to keep this code with adding code that checking same LUN for
fast path.
  
> However, I think there can be up to 32 regular luns,
> meaning UFS_UPIU_MAX_UNIT_NUM_ID need to be fixed as well.

OK, it can be fixed another patch.

Thanks,
Daejun