ide: add ide_pad_transfer() helper

* Add ide_pad_transfer() helper (which uses ->{in,out}put_data methods
  internally so the transfer is also padded to drive+host requirements)
  and use it instead of ide_atapi_{write_zeros,discard_data}().

* Remove no longer needed ide_atapi_{write_zeros,discard_data}().

Cc: Borislav Petkov <petkovbb@gmail.com>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide-floppy.c

@@ -262,10 +262,7 @@ static void ide_floppy_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
 	if (bcount) {
 		printk(KERN_ERR "%s: leftover data in %s, bcount == %d\n",
 				drive->name, __func__, bcount);
-		if (direction)
-			ide_atapi_write_zeros(drive, bcount);
-		else
-			ide_atapi_discard_data(drive, bcount);
+		ide_pad_transfer(drive, direction, bcount);
 	}
 }
 
@@ -491,7 +488,7 @@ static ide_startstop_t idefloppy_pc_intr(ide_drive_t *drive)
 				printk(KERN_ERR "ide-floppy: The floppy wants "
 					"to send us more data than expected "
 					"- discarding data\n");
-				ide_atapi_discard_data(drive, bcount);
+				ide_pad_transfer(drive, 0, bcount);
 
 				ide_set_handler(drive,
 						&idefloppy_pc_intr,

drivers/ide/ide-io.c

@@ -1642,3 +1642,18 @@ void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma)
 }
 
 EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load);
+
+void ide_pad_transfer(ide_drive_t *drive, int write, int len)
+{
+	ide_hwif_t *hwif = drive->hwif;
+	u8 buf[4] = { 0 };
+
+	while (len > 0) {
+		if (write)
+			hwif->output_data(drive, NULL, buf, min(4, len));
+		else
+			hwif->input_data(drive, NULL, buf, min(4, len));
+		len -= 4;
+	}
+}
+EXPORT_SYMBOL_GPL(ide_pad_transfer);

drivers/ide/ide-tape.c

@@ -395,7 +395,7 @@ static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
 		if (bh == NULL) {
 			printk(KERN_ERR "ide-tape: bh == NULL in "
 				"idetape_input_buffers\n");
-			ide_atapi_discard_data(drive, bcount);
+			ide_pad_transfer(drive, 0, bcount);
 			return;
 		}
 		count = min(
@@ -871,7 +871,7 @@ static ide_startstop_t idetape_pc_intr(ide_drive_t *drive)
 				printk(KERN_ERR "ide-tape: The tape wants to "
 					"send us more data than expected "
 					"- discarding data\n");
-				ide_atapi_discard_data(drive, bcount);
+				ide_pad_transfer(drive, 0, bcount);
 				ide_set_handler(drive, &idetape_pc_intr,
 						IDETAPE_WAIT_CMD, NULL);
 				return ide_started;

drivers/scsi/ide-scsi.c

@@ -164,7 +164,7 @@ static void idescsi_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
 
 	if (bcount) {
 		printk (KERN_ERR "ide-scsi: scatter gather table too small, discarding data\n");
-		ide_atapi_discard_data(drive, bcount);
+		ide_pad_transfer(drive, 0, bcount);
 	}
 }
 
@@ -201,7 +201,7 @@ static void idescsi_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
 
 	if (bcount) {
 		printk (KERN_ERR "ide-scsi: scatter gather table too small, padding with zeros\n");
-		ide_atapi_write_zeros(drive, bcount);
+		ide_pad_transfer(drive, 1, bcount);
 	}
 }
 
@@ -438,7 +438,7 @@ static ide_startstop_t idescsi_pc_intr (ide_drive_t *drive)
 				}
 				pc->xferred += temp;
 				pc->cur_pos += temp;
-				ide_atapi_discard_data(drive, bcount - temp);
+				ide_pad_transfer(drive, 0, bcount - temp);
 				ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
 				return ide_started;
 			}

include/linux/ide.h

@@ -827,6 +827,8 @@ void ide_execute_command(ide_drive_t *, u8, ide_handler_t *, unsigned int,
 
 void ide_execute_pkt_cmd(ide_drive_t *);
 
+void ide_pad_transfer(ide_drive_t *, int, int);
+
 ide_startstop_t __ide_error(ide_drive_t *, struct request *, u8, u8);
 
 ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, byte stat);
@@ -1359,27 +1361,4 @@ static inline u8 ide_read_error(ide_drive_t *drive)
 
 	return hwif->INB(hwif->io_ports.error_addr);
 }
-
-/*
- * Too bad. The drive wants to send us data which we are not ready to accept.
- * Just throw it away.
- */
-static inline void ide_atapi_discard_data(ide_drive_t *drive, unsigned bcount)
-{
-	ide_hwif_t *hwif = drive->hwif;
-
-	/* FIXME: use ->input_data */
-	while (bcount--)
-		(void)hwif->INB(hwif->io_ports.data_addr);
-}
-
-static inline void ide_atapi_write_zeros(ide_drive_t *drive, unsigned bcount)
-{
-	ide_hwif_t *hwif = drive->hwif;
-
-	/* FIXME: use ->output_data */
-	while (bcount--)
-		hwif->OUTB(0, hwif->io_ports.data_addr);
-}
-
 #endif /* _IDE_H */