ide: add ide_pc_intr() helper

* ide-tape.c: add 'drive' argument to idetape_update_buffers().

* Add generic ide_pc_intr() helper to ide-atapi.c and then
  convert ide-{floppy,tape,scsi} device drivers to use it.

* ide-tape.c: remove no longer needed DBG_PC_INTR.

There should be no functional changes caused by this patch
(unless the debugging is explicitely compiled in).

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
index 70aef97..0f3602a 100644
--- a/drivers/ide/ide-floppy.c
+++ b/drivers/ide/ide-floppy.c
@@ -388,132 +388,10 @@
 static ide_startstop_t idefloppy_pc_intr(ide_drive_t *drive)
 {
 	idefloppy_floppy_t *floppy = drive->driver_data;
-	ide_hwif_t *hwif = drive->hwif;
-	struct ide_atapi_pc *pc = floppy->pc;
-	struct request *rq = pc->rq;
-	xfer_func_t *xferfunc;
-	unsigned int temp;
-	int dma_error = 0;
-	u16 bcount;
-	u8 stat, ireason;
 
-	debug_log("Enter %s - interrupt handler\n", __func__);
-
-	/* Clear the interrupt */
-	stat = ide_read_status(drive);
-
-	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
-		dma_error = hwif->dma_ops->dma_end(drive);
-		if (dma_error) {
-			printk(KERN_ERR "%s: DMA %s error\n", drive->name,
-					rq_data_dir(rq) ? "write" : "read");
-			pc->flags |= PC_FLAG_DMA_ERROR;
-		} else {
-			pc->xferred = pc->req_xfer;
-			idefloppy_update_buffers(drive, pc);
-		}
-		debug_log("%s: DMA finished\n", drive->name);
-	}
-
-	/* No more interrupts */
-	if ((stat & DRQ_STAT) == 0) {
-		debug_log("Packet command completed, %d bytes transferred\n",
-				pc->xferred);
-		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
-
-		local_irq_enable_in_hardirq();
-
-		if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
-			/* Error detected */
-			debug_log("%s: I/O error\n", drive->name);
-			rq->errors++;
-			if (pc->c[0] == GPCMD_REQUEST_SENSE) {
-				printk(KERN_ERR "%s: I/O error in request sense"
-						" command\n", drive->name);
-				return ide_do_reset(drive);
-			}
-
-			debug_log("[cmd %x]: check condition\n", pc->c[0]);
-
-			/* Retry operation */
-			idefloppy_retry_pc(drive);
-			/* queued, but not started */
-			return ide_stopped;
-		}
-		pc->error = 0;
-		/* Command finished - Call the callback function */
-		pc->callback(drive);
-		return ide_stopped;
-	}
-
-	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
-		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
-		printk(KERN_ERR "%s: The device wants to issue more interrupts "
-				"in DMA mode\n", drive->name);
-		ide_dma_off(drive);
-		return ide_do_reset(drive);
-	}
-
-	/* Get the number of bytes to transfer */
-	bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) |
-		  hwif->INB(hwif->io_ports.lbam_addr);
-	/* on this interrupt */
-	ireason = hwif->INB(hwif->io_ports.nsect_addr);
-
-	if (ireason & CD) {
-		printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
-		return ide_do_reset(drive);
-	}
-	if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
-		/* Hopefully, we will never get here */
-		printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
-				"to %s!\n", drive->name,
-				(ireason & IO) ? "Write" : "Read",
-				(ireason & IO) ? "Read" : "Write");
-		return ide_do_reset(drive);
-	}
-	if (!(pc->flags & PC_FLAG_WRITING)) {
-		/* Reading - Check that we have enough space */
-		temp = pc->xferred + bcount;
-		if (temp > pc->req_xfer) {
-			if (temp > pc->buf_size) {
-				printk(KERN_ERR "%s: The device wants to send "
-						"us more data than expected - "
-						"discarding data\n",
-						drive->name);
-				ide_pad_transfer(drive, 0, bcount);
-
-				ide_set_handler(drive,
-						&idefloppy_pc_intr,
-						IDEFLOPPY_WAIT_CMD,
-						NULL);
-				return ide_started;
-			}
-			debug_log("The device wants to send us more data than "
-				  "expected - allowing transfer\n");
-		}
-	}
-	if (pc->flags & PC_FLAG_WRITING)
-		xferfunc = hwif->output_data;
-	else
-		xferfunc = hwif->input_data;
-
-	if (pc->buf)
-		xferfunc(drive, NULL, pc->cur_pos, bcount);
-	else
-		ide_floppy_io_buffers(drive, pc, bcount,
-				      !!(pc->flags & PC_FLAG_WRITING));
-
-	/* Update the current position */
-	pc->xferred += bcount;
-	pc->cur_pos += bcount;
-
-	debug_log("[cmd %x] transferred %d bytes on that intr.\n",
-		  pc->c[0], bcount);
-
-	/* And set the interrupt handler again */
-	ide_set_handler(drive, &idefloppy_pc_intr, IDEFLOPPY_WAIT_CMD, NULL);
-	return ide_started;
+	return ide_pc_intr(drive, floppy->pc, idefloppy_pc_intr,
+			   IDEFLOPPY_WAIT_CMD, NULL, idefloppy_update_buffers,
+			   idefloppy_retry_pc, NULL, ide_floppy_io_buffers);
 }
 
 /*