scsi: ufs: ufshpb: Rewind the read timeout on every read

The purpose of the "cold"-timer is not to hang-on to active regions with no
reads.  Therefore the read timeout should be rewound on every read, and not
just when the region is activated.

Link: https://lore.kernel.org/r/20210808090024.21721-2-avri.altman@wdc.com
Fixes: 13c044e9 (scsi: ufs: ufshpb: Add "cold" regions timer)
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ufs/ufshpb.c

@@ -178,9 +178,19 @@ static void ufshpb_iterate_rgn(struct ufshpb_lu *hpb, int rgn_idx, int srgn_idx,
 		set_bit_len = cnt;
 
 	spin_lock_irqsave(&hpb->rgn_state_lock, flags);
-	if (set_dirty && rgn->rgn_state != HPB_RGN_INACTIVE &&
-	    srgn->srgn_state == HPB_SRGN_VALID)
-		bitmap_set(srgn->mctx->ppn_dirty, srgn_offset, set_bit_len);
+	if (rgn->rgn_state != HPB_RGN_INACTIVE) {
+		if (set_dirty) {
+			if (srgn->srgn_state == HPB_SRGN_VALID)
+				bitmap_set(srgn->mctx->ppn_dirty, srgn_offset,
+					   set_bit_len);
+		} else if (hpb->is_hcm) {
+			 /* rewind the read timer for lru regions */
+			rgn->read_timeout = ktime_add_ms(ktime_get(),
+					rgn->hpb->params.read_timeout_ms);
+			rgn->read_timeout_expiries =
+				rgn->hpb->params.read_timeout_expiries;
+		}
+	}
 	spin_unlock_irqrestore(&hpb->rgn_state_lock, flags);
 
 	if (hpb->is_hcm && prev_srgn != srgn) {