tx493[89]ide: Fix length for __ide_flush_dcache_range

This fixes data corruption on PIO mode.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: stable <stable@kernel.org>
Cc: sshtylyov@ru.mvista.com
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/tx4938ide.c

@@ -181,7 +181,7 @@ static void tx4938ide_input_data_swap(ide_drive_t *drive, struct request *rq,
 
 	while (count--)
 		*ptr++ = cpu_to_le16(__raw_readw((void __iomem *)port));
-	__ide_flush_dcache_range((unsigned long)buf, count * 2);
+	__ide_flush_dcache_range((unsigned long)buf, roundup(len, 2));
 }
 
 static void tx4938ide_output_data_swap(ide_drive_t *drive, struct request *rq,
@@ -195,7 +195,7 @@ static void tx4938ide_output_data_swap(ide_drive_t *drive, struct request *rq,
 		__raw_writew(le16_to_cpu(*ptr), (void __iomem *)port);
 		ptr++;
 	}
-	__ide_flush_dcache_range((unsigned long)buf, count * 2);
+	__ide_flush_dcache_range((unsigned long)buf, roundup(len, 2));
 }
 
 static const struct ide_tp_ops tx4938ide_tp_ops = {

drivers/ide/tx4939ide.c

@@ -564,7 +564,7 @@ static void tx4939ide_input_data_swap(ide_drive_t *drive, struct request *rq,
 
 	while (count--)
 		*ptr++ = cpu_to_le16(__raw_readw((void __iomem *)port));
-	__ide_flush_dcache_range((unsigned long)buf, count * 2);
+	__ide_flush_dcache_range((unsigned long)buf, roundup(len, 2));
 }
 
 static void tx4939ide_output_data_swap(ide_drive_t *drive, struct request *rq,
@@ -578,7 +578,7 @@ static void tx4939ide_output_data_swap(ide_drive_t *drive, struct request *rq,
 		__raw_writew(le16_to_cpu(*ptr), (void __iomem *)port);
 		ptr++;
 	}
-	__ide_flush_dcache_range((unsigned long)buf, count * 2);
+	__ide_flush_dcache_range((unsigned long)buf, roundup(len, 2));
 }
 
 static const struct ide_tp_ops tx4939ide_tp_ops = {