--- linux/drivers/scsi/libata-core.c.ori	2005-09-02 17:59:15.000000000 +0800
+++ pio1/drivers/scsi/libata-core.c	2005-09-02 18:37:26.000000000 +0800
@@ -2461,9 +2461,12 @@
  *
  *	LOCKING:
  *	None.  (executing in kernel thread context)
+ *
+ *	RETURNS:
+ *	Zero if qc completed, non-zero otherwise.
  */
 
-static void ata_pio_complete (struct ata_port *ap)
+static int ata_pio_complete (struct ata_port *ap)
 {
 	struct ata_queued_cmd *qc;
 	u8 drv_stat;
@@ -2482,14 +2485,14 @@
 		if (drv_stat & (ATA_BUSY | ATA_DRQ)) {
 			ap->pio_task_state = PIO_ST_LAST_POLL;
 			ap->pio_task_timeout = jiffies + ATA_TMOUT_PIO;
-			return;
+			return 1; /* qc not completed */
 		}
 	}
 
 	drv_stat = ata_wait_idle(ap);
 	if (!ata_ok(drv_stat)) {
 		ap->pio_task_state = PIO_ST_ERR;
-		return;
+		return 1; /* qc not completed */
 	}
 
 	qc = ata_qc_from_tag(ap, ap->active_tag);
@@ -2498,6 +2501,7 @@
 	ap->pio_task_state = PIO_ST_IDLE;
 
 	ata_poll_qc_complete(qc, drv_stat);
+	return 0; /* qc completed */
 }
 
 
@@ -2813,9 +2817,12 @@
  *
  *	LOCKING:
  *	None.  (executing in kernel thread context)
+ *
+ *	RETURNS:
+ *	Zero if qc completed, non-zero otherwise.
  */
 
-static void ata_pio_block(struct ata_port *ap)
+static int ata_pio_block(struct ata_port *ap)
 {
 	struct ata_queued_cmd *qc;
 	u8 status;
@@ -2835,7 +2842,7 @@
 		if (status & ATA_BUSY) {
 			ap->pio_task_state = PIO_ST_POLL;
 			ap->pio_task_timeout = jiffies + ATA_TMOUT_PIO;
-			return;
+			return 1; /* qc not completed */
 		}
 	}
 
@@ -2848,7 +2855,7 @@
 			ap->pio_task_state = PIO_ST_IDLE;
 
 			ata_poll_qc_complete(qc, status);
-			return;
+			return 0; /* qc completed */
 		}
 
 		atapi_pio_bytes(qc);
@@ -2856,11 +2863,13 @@
 		/* handle BSY=0, DRQ=0 as error */
 		if ((status & ATA_DRQ) == 0) {
 			ap->pio_task_state = PIO_ST_ERR;
-			return;
+			return 1; /* qc not completed */
 		}
 
 		ata_pio_sector(qc);
 	}
+
+	return 1; /* qc not completed */
 }
 
 static void ata_pio_error(struct ata_port *ap)