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authorChristoph Hellwig <hch@lst.de>2021-06-16 15:46:58 +0200
committerJens Axboe <axboe@kernel.dk>2021-06-16 08:53:58 -0600
commitb7fb14d3ac63117e0e8beabe75f4ea52051fbe3a (patch)
treec41a62265a9e8fb40e8d3572a984c5ad8d313b7c /drivers/ide/ide-tape.c
parentb90257bfddbd01f3686d99c256ae6dd24a6a1deb (diff)
downloadlinux-b7fb14d3ac63117e0e8beabe75f4ea52051fbe3a.tar.gz
ide: remove the legacy ide driver
The legay ide driver has been replace with libata starting in 2003 and has
been scheduled for removal for a while.  Finally kill it off so that we
can start cleaning up various bits of cruft it forced on the block layer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/ide/ide-tape.c')
-rw-r--r--drivers/ide/ide-tape.c2083
1 files changed, 0 insertions, 2083 deletions
diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
deleted file mode 100644
index fa05e7e7d609..000000000000
--- a/drivers/ide/ide-tape.c
+++ /dev/null
@@ -1,2083 +0,0 @@
-/*
- * IDE ATAPI streaming tape driver.
- *
- * Copyright (C) 1995-1999  Gadi Oxman <gadio@netvision.net.il>
- * Copyright (C) 2003-2005  Bartlomiej Zolnierkiewicz
- *
- * This driver was constructed as a student project in the software laboratory
- * of the faculty of electrical engineering in the Technion - Israel's
- * Institute Of Technology, with the guide of Avner Lottem and Dr. Ilana David.
- *
- * It is hereby placed under the terms of the GNU general public license.
- * (See linux/COPYING).
- *
- * For a historical changelog see
- * Documentation/ide/ChangeLog.ide-tape.1995-2002
- */
-
-#define DRV_NAME "ide-tape"
-
-#define IDETAPE_VERSION "1.20"
-
-#include <linux/compat.h>
-#include <linux/module.h>
-#include <linux/types.h>
-#include <linux/string.h>
-#include <linux/kernel.h>
-#include <linux/delay.h>
-#include <linux/timer.h>
-#include <linux/mm.h>
-#include <linux/interrupt.h>
-#include <linux/jiffies.h>
-#include <linux/major.h>
-#include <linux/errno.h>
-#include <linux/genhd.h>
-#include <linux/seq_file.h>
-#include <linux/slab.h>
-#include <linux/pci.h>
-#include <linux/ide.h>
-#include <linux/completion.h>
-#include <linux/bitops.h>
-#include <linux/mutex.h>
-#include <scsi/scsi.h>
-
-#include <asm/byteorder.h>
-#include <linux/uaccess.h>
-#include <linux/io.h>
-#include <asm/unaligned.h>
-#include <linux/mtio.h>
-
-/* define to see debug info */
-#undef IDETAPE_DEBUG_LOG
-
-#ifdef IDETAPE_DEBUG_LOG
-#define ide_debug_log(lvl, fmt, args...) __ide_debug_log(lvl, fmt, ## args)
-#else
-#define ide_debug_log(lvl, fmt, args...) do {} while (0)
-#endif
-
-/**************************** Tunable parameters *****************************/
-/*
- * After each failed packet command we issue a request sense command and retry
- * the packet command IDETAPE_MAX_PC_RETRIES times.
- *
- * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
- */
-#define IDETAPE_MAX_PC_RETRIES		3
-
-/*
- * The following parameter is used to select the point in the internal tape fifo
- * in which we will start to refill the buffer. Decreasing the following
- * parameter will improve the system's latency and interactive response, while
- * using a high value might improve system throughput.
- */
-#define IDETAPE_FIFO_THRESHOLD		2
-
-/*
- * DSC polling parameters.
- *
- * Polling for DSC (a single bit in the status register) is a very important
- * function in ide-tape. There are two cases in which we poll for DSC:
- *
- * 1. Before a read/write packet command, to ensure that we can transfer data
- * from/to the tape's data buffers, without causing an actual media access.
- * In case the tape is not ready yet, we take out our request from the device
- * request queue, so that ide.c could service requests from the other device
- * on the same interface in the meantime.
- *
- * 2. After the successful initialization of a "media access packet command",
- * which is a command that can take a long time to complete (the interval can
- * range from several seconds to even an hour). Again, we postpone our request
- * in the middle to free the bus for the other device. The polling frequency
- * here should be lower than the read/write frequency since those media access
- * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST
- * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD
- * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min).
- *
- * We also set a timeout for the timer, in case something goes wrong. The
- * timeout should be longer then the maximum execution time of a tape operation.
- */
-
-/* DSC timings. */
-#define IDETAPE_DSC_RW_MIN		5*HZ/100	/* 50 msec */
-#define IDETAPE_DSC_RW_MAX		40*HZ/100	/* 400 msec */
-#define IDETAPE_DSC_RW_TIMEOUT		2*60*HZ		/* 2 minutes */
-#define IDETAPE_DSC_MA_FAST		2*HZ		/* 2 seconds */
-#define IDETAPE_DSC_MA_THRESHOLD	5*60*HZ		/* 5 minutes */
-#define IDETAPE_DSC_MA_SLOW		30*HZ		/* 30 seconds */
-#define IDETAPE_DSC_MA_TIMEOUT		2*60*60*HZ	/* 2 hours */
-
-/*************************** End of tunable parameters ***********************/
-
-/* tape directions */
-enum {
-	IDETAPE_DIR_NONE  = (1 << 0),
-	IDETAPE_DIR_READ  = (1 << 1),
-	IDETAPE_DIR_WRITE = (1 << 2),
-};
-
-/* Tape door status */
-#define DOOR_UNLOCKED			0
-#define DOOR_LOCKED			1
-#define DOOR_EXPLICITLY_LOCKED		2
-
-/* Some defines for the SPACE command */
-#define IDETAPE_SPACE_OVER_FILEMARK	1
-#define IDETAPE_SPACE_TO_EOD		3
-
-/* Some defines for the LOAD UNLOAD command */
-#define IDETAPE_LU_LOAD_MASK		1
-#define IDETAPE_LU_RETENSION_MASK	2
-#define IDETAPE_LU_EOT_MASK		4
-
-/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
-#define IDETAPE_BLOCK_DESCRIPTOR	0
-#define IDETAPE_CAPABILITIES_PAGE	0x2a
-
-/*
- * Most of our global data which we need to save even as we leave the driver due
- * to an interrupt or a timer event is stored in the struct defined below.
- */
-typedef struct ide_tape_obj {
-	ide_drive_t		*drive;
-	struct ide_driver	*driver;
-	struct gendisk		*disk;
-	struct device		dev;
-
-	/* used by REQ_IDETAPE_{READ,WRITE} requests */
-	struct ide_atapi_pc queued_pc;
-
-	/*
-	 * DSC polling variables.
-	 *
-	 * While polling for DSC we use postponed_rq to postpone the current
-	 * request so that ide.c will be able to service pending requests on the
-	 * other device. Note that at most we will have only one DSC (usually
-	 * data transfer) request in the device request queue.
-	 */
-	bool postponed_rq;
-
-	/* The time in which we started polling for DSC */
-	unsigned long dsc_polling_start;
-	/* Timer used to poll for dsc */
-	struct timer_list dsc_timer;
-	/* Read/Write dsc polling frequency */
-	unsigned long best_dsc_rw_freq;
-	unsigned long dsc_poll_freq;
-	unsigned long dsc_timeout;
-
-	/* Read position information */
-	u8 partition;
-	/* Current block */
-	unsigned int first_frame;
-
-	/* Last error information */
-	u8 sense_key, asc, ascq;
-
-	/* Character device operation */
-	unsigned int minor;
-	/* device name */
-	char name[4];
-	/* Current character device data transfer direction */
-	u8 chrdev_dir;
-
-	/* tape block size, usually 512 or 1024 bytes */
-	unsigned short blk_size;
-	int user_bs_factor;
-
-	/* Copy of the tape's Capabilities and Mechanical Page */
-	u8 caps[20];
-
-	/*
-	 * Active data transfer request parameters.
-	 *
-	 * At most, there is only one ide-tape originated data transfer request
-	 * in the device request queue. This allows ide.c to easily service
-	 * requests from the other device when we postpone our active request.
-	 */
-
-	/* Data buffer size chosen based on the tape's recommendation */
-	int buffer_size;
-	/* Staging buffer of buffer_size bytes */
-	void *buf;
-	/* The read/write cursor */
-	void *cur;
-	/* The number of valid bytes in buf */
-	size_t valid;
-
-	/* Measures average tape speed */
-	unsigned long avg_time;
-	int avg_size;
-	int avg_speed;
-
-	/* the door is currently locked */
-	int door_locked;
-	/* the tape hardware is write protected */
-	char drv_write_prot;
-	/* the tape is write protected (hardware or opened as read-only) */
-	char write_prot;
-} idetape_tape_t;
-
-static DEFINE_MUTEX(ide_tape_mutex);
-static DEFINE_MUTEX(idetape_ref_mutex);
-
-static DEFINE_MUTEX(idetape_chrdev_mutex);
-
-static struct class *idetape_sysfs_class;
-
-static void ide_tape_release(struct device *);
-
-static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
-
-static struct ide_tape_obj *ide_tape_get(struct gendisk *disk, bool cdev,
-					 unsigned int i)
-{
-	struct ide_tape_obj *tape = NULL;
-
-	mutex_lock(&idetape_ref_mutex);
-
-	if (cdev)
-		tape = idetape_devs[i];
-	else
-		tape = ide_drv_g(disk, ide_tape_obj);
-
-	if (tape) {
-		if (ide_device_get(tape->drive))
-			tape = NULL;
-		else
-			get_device(&tape->dev);
-	}
-
-	mutex_unlock(&idetape_ref_mutex);
-	return tape;
-}
-
-static void ide_tape_put(struct ide_tape_obj *tape)
-{
-	ide_drive_t *drive = tape->drive;
-
-	mutex_lock(&idetape_ref_mutex);
-	put_device(&tape->dev);
-	ide_device_put(drive);
-	mutex_unlock(&idetape_ref_mutex);
-}
-
-/*
- * called on each failed packet command retry to analyze the request sense. We
- * currently do not utilize this information.
- */
-static void idetape_analyze_error(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct ide_atapi_pc *pc = drive->failed_pc;
-	struct request *rq = drive->hwif->rq;
-	u8 *sense = bio_data(rq->bio);
-
-	tape->sense_key = sense[2] & 0xF;
-	tape->asc       = sense[12];
-	tape->ascq      = sense[13];
-
-	ide_debug_log(IDE_DBG_FUNC,
-		      "cmd: 0x%x, sense key = %x, asc = %x, ascq = %x",
-		      rq->cmd[0], tape->sense_key, tape->asc, tape->ascq);
-
-	/* correct remaining bytes to transfer */
-	if (pc->flags & PC_FLAG_DMA_ERROR)
-		scsi_req(rq)->resid_len = tape->blk_size * get_unaligned_be32(&sense[3]);
-
-	/*
-	 * If error was the result of a zero-length read or write command,
-	 * with sense key=5, asc=0x22, ascq=0, let it slide.  Some drives
-	 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
-	 */
-	if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
-	    /* length == 0 */
-	    && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
-		if (tape->sense_key == 5) {
-			/* don't report an error, everything's ok */
-			pc->error = 0;
-			/* don't retry read/write */
-			pc->flags |= PC_FLAG_ABORT;
-		}
-	}
-	if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
-		pc->error = IDE_DRV_ERROR_FILEMARK;
-		pc->flags |= PC_FLAG_ABORT;
-	}
-	if (pc->c[0] == WRITE_6) {
-		if ((sense[2] & 0x40) || (tape->sense_key == 0xd
-		     && tape->asc == 0x0 && tape->ascq == 0x2)) {
-			pc->error = IDE_DRV_ERROR_EOD;
-			pc->flags |= PC_FLAG_ABORT;
-		}
-	}
-	if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
-		if (tape->sense_key == 8) {
-			pc->error = IDE_DRV_ERROR_EOD;
-			pc->flags |= PC_FLAG_ABORT;
-		}
-		if (!(pc->flags & PC_FLAG_ABORT) &&
-		    (blk_rq_bytes(rq) - scsi_req(rq)->resid_len))
-			pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
-	}
-}
-
-static void ide_tape_handle_dsc(ide_drive_t *);
-
-static int ide_tape_callback(ide_drive_t *drive, int dsc)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct ide_atapi_pc *pc = drive->pc;
-	struct request *rq = drive->hwif->rq;
-	int uptodate = pc->error ? 0 : 1;
-	int err = uptodate ? 0 : IDE_DRV_ERROR_GENERAL;
-
-	ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, dsc: %d, err: %d", rq->cmd[0],
-		      dsc, err);
-
-	if (dsc)
-		ide_tape_handle_dsc(drive);
-
-	if (drive->failed_pc == pc)
-		drive->failed_pc = NULL;
-
-	if (pc->c[0] == REQUEST_SENSE) {
-		if (uptodate)
-			idetape_analyze_error(drive);
-		else
-			printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
-					"itself - Aborting request!\n");
-	} else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
-		unsigned int blocks =
-			(blk_rq_bytes(rq) - scsi_req(rq)->resid_len) / tape->blk_size;
-
-		tape->avg_size += blocks * tape->blk_size;
-
-		if (time_after_eq(jiffies, tape->avg_time + HZ)) {
-			tape->avg_speed = tape->avg_size * HZ /
-				(jiffies - tape->avg_time) / 1024;
-			tape->avg_size = 0;
-			tape->avg_time = jiffies;
-		}
-
-		tape->first_frame += blocks;
-
-		if (pc->error) {
-			uptodate = 0;
-			err = pc->error;
-		}
-	}
-	scsi_req(rq)->result = err;
-
-	return uptodate;
-}
-
-/*
- * Postpone the current request so that ide.c will be able to service requests
- * from another device on the same port while we are polling for DSC.
- */
-static void ide_tape_stall_queue(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-
-	ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, dsc_poll_freq: %lu",
-		      drive->hwif->rq->cmd[0], tape->dsc_poll_freq);
-
-	tape->postponed_rq = true;
-
-	ide_stall_queue(drive, tape->dsc_poll_freq);
-}
-
-static void ide_tape_handle_dsc(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-
-	/* Media access command */
-	tape->dsc_polling_start = jiffies;
-	tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
-	tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
-	/* Allow ide.c to handle other requests */
-	ide_tape_stall_queue(drive);
-}
-
-/*
- * Packet Command Interface
- *
- * The current Packet Command is available in drive->pc, and will not change
- * until we finish handling it. Each packet command is associated with a
- * callback function that will be called when the command is finished.
- *
- * The handling will be done in three stages:
- *
- * 1. ide_tape_issue_pc will send the packet command to the drive, and will set
- * the interrupt handler to ide_pc_intr.
- *
- * 2. On each interrupt, ide_pc_intr will be called. This step will be
- * repeated until the device signals us that no more interrupts will be issued.
- *
- * 3. ATAPI Tape media access commands have immediate status with a delayed
- * process. In case of a successful initiation of a media access packet command,
- * the DSC bit will be set when the actual execution of the command is finished.
- * Since the tape drive will not issue an interrupt, we have to poll for this
- * event. In this case, we define the request as "low priority request" by
- * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
- * exit the driver.
- *
- * ide.c will then give higher priority to requests which originate from the
- * other device, until will change rq_status to RQ_ACTIVE.
- *
- * 4. When the packet command is finished, it will be checked for errors.
- *
- * 5. In case an error was found, we queue a request sense packet command in
- * front of the request queue and retry the operation up to
- * IDETAPE_MAX_PC_RETRIES times.
- *
- * 6. In case no error was found, or we decided to give up and not to retry
- * again, the callback function will be called and then we will handle the next
- * request.
- */
-
-static ide_startstop_t ide_tape_issue_pc(ide_drive_t *drive,
-					 struct ide_cmd *cmd,
-					 struct ide_atapi_pc *pc)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct request *rq = drive->hwif->rq;
-
-	if (drive->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
-		drive->failed_pc = pc;
-
-	/* Set the current packet command */
-	drive->pc = pc;
-
-	if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
-		(pc->flags & PC_FLAG_ABORT)) {
-
-		/*
-		 * We will "abort" retrying a packet command in case legitimate
-		 * error code was received (crossing a filemark, or end of the
-		 * media, for example).
-		 */
-		if (!(pc->flags & PC_FLAG_ABORT)) {
-			if (!(pc->c[0] == TEST_UNIT_READY &&
-			      tape->sense_key == 2 && tape->asc == 4 &&
-			     (tape->ascq == 1 || tape->ascq == 8))) {
-				printk(KERN_ERR "ide-tape: %s: I/O error, "
-						"pc = %2x, key = %2x, "
-						"asc = %2x, ascq = %2x\n",
-						tape->name, pc->c[0],
-						tape->sense_key, tape->asc,
-						tape->ascq);
-			}
-			/* Giving up */
-			pc->error = IDE_DRV_ERROR_GENERAL;
-		}
-
-		drive->failed_pc = NULL;
-		drive->pc_callback(drive, 0);
-		ide_complete_rq(drive, BLK_STS_IOERR, blk_rq_bytes(rq));
-		return ide_stopped;
-	}
-	ide_debug_log(IDE_DBG_SENSE, "retry #%d, cmd: 0x%02x", pc->retries,
-		      pc->c[0]);
-
-	pc->retries++;
-
-	return ide_issue_pc(drive, cmd);
-}
-
-/* A mode sense command is used to "sense" tape parameters. */
-static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
-{
-	ide_init_pc(pc);
-	pc->c[0] = MODE_SENSE;
-	if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
-		/* DBD = 1 - Don't return block descriptors */
-		pc->c[1] = 8;
-	pc->c[2] = page_code;
-	/*
-	 * Changed pc->c[3] to 0 (255 will at best return unused info).
-	 *
-	 * For SCSI this byte is defined as subpage instead of high byte
-	 * of length and some IDE drives seem to interpret it this way
-	 * and return an error when 255 is used.
-	 */
-	pc->c[3] = 0;
-	/* We will just discard data in that case */
-	pc->c[4] = 255;
-	if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
-		pc->req_xfer = 12;
-	else if (page_code == IDETAPE_CAPABILITIES_PAGE)
-		pc->req_xfer = 24;
-	else
-		pc->req_xfer = 50;
-}
-
-static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
-{
-	ide_hwif_t *hwif = drive->hwif;
-	idetape_tape_t *tape = drive->driver_data;
-	struct ide_atapi_pc *pc = drive->pc;
-	u8 stat;
-
-	stat = hwif->tp_ops->read_status(hwif);
-
-	if (stat & ATA_DSC) {
-		if (stat & ATA_ERR) {
-			/* Error detected */
-			if (pc->c[0] != TEST_UNIT_READY)
-				printk(KERN_ERR "ide-tape: %s: I/O error, ",
-						tape->name);
-			/* Retry operation */
-			ide_retry_pc(drive);
-			return ide_stopped;
-		}
-		pc->error = 0;
-	} else {
-		pc->error = IDE_DRV_ERROR_GENERAL;
-		drive->failed_pc = NULL;
-	}
-	drive->pc_callback(drive, 0);
-	return ide_stopped;
-}
-
-static void ide_tape_create_rw_cmd(idetape_tape_t *tape,
-				   struct ide_atapi_pc *pc, struct request *rq,
-				   u8 opcode)
-{
-	unsigned int length = blk_rq_sectors(rq) / (tape->blk_size >> 9);
-
-	ide_init_pc(pc);
-	put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
-	pc->c[1] = 1;
-
-	if (blk_rq_bytes(rq) == tape->buffer_size)
-		pc->flags |= PC_FLAG_DMA_OK;
-
-	if (opcode == READ_6)
-		pc->c[0] = READ_6;
-	else if (opcode == WRITE_6) {
-		pc->c[0] = WRITE_6;
-		pc->flags |= PC_FLAG_WRITING;
-	}
-
-	memcpy(scsi_req(rq)->cmd, pc->c, 12);
-}
-
-static ide_startstop_t idetape_do_request(ide_drive_t *drive,
-					  struct request *rq, sector_t block)
-{
-	ide_hwif_t *hwif = drive->hwif;
-	idetape_tape_t *tape = drive->driver_data;
-	struct ide_atapi_pc *pc = NULL;
-	struct ide_cmd cmd;
-	struct scsi_request *req = scsi_req(rq);
-	u8 stat;
-
-	ide_debug_log(IDE_DBG_RQ, "cmd: 0x%x, sector: %llu, nr_sectors: %u",
-		      req->cmd[0], (unsigned long long)blk_rq_pos(rq),
-		      blk_rq_sectors(rq));
-
-	BUG_ON(!blk_rq_is_private(rq));
-	BUG_ON(ide_req(rq)->type != ATA_PRIV_MISC &&
-	       ide_req(rq)->type != ATA_PRIV_SENSE);
-
-	/* Retry a failed packet command */
-	if (drive->failed_pc && drive->pc->c[0] == REQUEST_SENSE) {
-		pc = drive->failed_pc;
-		goto out;
-	}
-
-	/*
-	 * If the tape is still busy, postpone our request and service
-	 * the other device meanwhile.
-	 */
-	stat = hwif->tp_ops->read_status(hwif);
-
-	if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 &&
-	    (req->cmd[13] & REQ_IDETAPE_PC2) == 0)
-		drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
-
-	if (drive->dev_flags & IDE_DFLAG_POST_RESET) {
-		drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
-		drive->dev_flags &= ~IDE_DFLAG_POST_RESET;
-	}
-
-	if (!(drive->atapi_flags & IDE_AFLAG_IGNORE_DSC) &&
-	    !(stat & ATA_DSC)) {
-		if (!tape->postponed_rq) {
-			tape->dsc_polling_start = jiffies;
-			tape->dsc_poll_freq = tape->best_dsc_rw_freq;
-			tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
-		} else if (time_after(jiffies, tape->dsc_timeout)) {
-			printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
-				tape->name);
-			if (req->cmd[13] & REQ_IDETAPE_PC2) {
-				idetape_media_access_finished(drive);
-				return ide_stopped;
-			} else {
-				return ide_do_reset(drive);
-			}
-		} else if (time_after(jiffies,
-					tape->dsc_polling_start +
-					IDETAPE_DSC_MA_THRESHOLD))
-			tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
-		ide_tape_stall_queue(drive);
-		return ide_stopped;
-	} else {
-		drive->atapi_flags &= ~IDE_AFLAG_IGNORE_DSC;
-		tape->postponed_rq = false;
-	}
-
-	if (req->cmd[13] & REQ_IDETAPE_READ) {
-		pc = &tape->queued_pc;
-		ide_tape_create_rw_cmd(tape, pc, rq, READ_6);
-		goto out;
-	}
-	if (req->cmd[13] & REQ_IDETAPE_WRITE) {
-		pc = &tape->queued_pc;
-		ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6);
-		goto out;
-	}
-	if (req->cmd[13] & REQ_IDETAPE_PC1) {
-		pc = (struct ide_atapi_pc *)ide_req(rq)->special;
-		req->cmd[13] &= ~(REQ_IDETAPE_PC1);
-		req->cmd[13] |= REQ_IDETAPE_PC2;
-		goto out;
-	}
-	if (req->cmd[13] & REQ_IDETAPE_PC2) {
-		idetape_media_access_finished(drive);
-		return ide_stopped;
-	}
-	BUG();
-
-out:
-	/* prepare sense request for this command */
-	ide_prep_sense(drive, rq);
-
-	memset(&cmd, 0, sizeof(cmd));
-
-	if (rq_data_dir(rq))
-		cmd.tf_flags |= IDE_TFLAG_WRITE;
-
-	cmd.rq = rq;
-
-	ide_init_sg_cmd(&cmd, blk_rq_bytes(rq));
-	ide_map_sg(drive, &cmd);
-
-	return ide_tape_issue_pc(drive, &cmd, pc);
-}
-
-/*
- * Write a filemark if write_filemark=1. Flush the device buffers without
- * writing a filemark otherwise.
- */
-static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
-		struct ide_atapi_pc *pc, int write_filemark)
-{
-	ide_init_pc(pc);
-	pc->c[0] = WRITE_FILEMARKS;
-	pc->c[4] = write_filemark;
-	pc->flags |= PC_FLAG_WAIT_FOR_DSC;
-}
-
-static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct gendisk *disk = tape->disk;
-	int load_attempted = 0;
-
-	/* Wait for the tape to become ready */
-	set_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT), &drive->atapi_flags);
-	timeout += jiffies;
-	while (time_before(jiffies, timeout)) {
-		if (ide_do_test_unit_ready(drive, disk) == 0)
-			return 0;
-		if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
-		    || (tape->asc == 0x3A)) {
-			/* no media */
-			if (load_attempted)
-				return -ENOMEDIUM;
-			ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
-			load_attempted = 1;
-		/* not about to be ready */
-		} else if (!(tape->sense_key == 2 && tape->asc == 4 &&
-			     (tape->ascq == 1 || tape->ascq == 8)))
-			return -EIO;
-		msleep(100);
-	}
-	return -EIO;
-}
-
-static int idetape_flush_tape_buffers(ide_drive_t *drive)
-{
-	struct ide_tape_obj *tape = drive->driver_data;
-	struct ide_atapi_pc pc;
-	int rc;
-
-	idetape_create_write_filemark_cmd(drive, &pc, 0);
-	rc = ide_queue_pc_tail(drive, tape->disk, &pc, NULL, 0);
-	if (rc)
-		return rc;
-	idetape_wait_ready(drive, 60 * 5 * HZ);
-	return 0;
-}
-
-static int ide_tape_read_position(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct ide_atapi_pc pc;
-	u8 buf[20];
-
-	ide_debug_log(IDE_DBG_FUNC, "enter");
-
-	/* prep cmd */
-	ide_init_pc(&pc);
-	pc.c[0] = READ_POSITION;
-	pc.req_xfer = 20;
-
-	if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer))
-		return -1;
-
-	if (!pc.error) {
-		ide_debug_log(IDE_DBG_FUNC, "BOP - %s",
-				(buf[0] & 0x80) ? "Yes" : "No");
-		ide_debug_log(IDE_DBG_FUNC, "EOP - %s",
-				(buf[0] & 0x40) ? "Yes" : "No");
-
-		if (buf[0] & 0x4) {
-			printk(KERN_INFO "ide-tape: Block location is unknown"
-					 "to the tape\n");
-			clear_bit(ilog2(IDE_AFLAG_ADDRESS_VALID),
-				  &drive->atapi_flags);
-			return -1;
-		} else {
-			ide_debug_log(IDE_DBG_FUNC, "Block Location: %u",
-				      be32_to_cpup((__be32 *)&buf[4]));
-
-			tape->partition = buf[1];
-			tape->first_frame = be32_to_cpup((__be32 *)&buf[4]);
-			set_bit(ilog2(IDE_AFLAG_ADDRESS_VALID),
-				&drive->atapi_flags);
-		}
-	}
-
-	return tape->first_frame;
-}
-
-static void idetape_create_locate_cmd(ide_drive_t *drive,
-		struct ide_atapi_pc *pc,
-		unsigned int block, u8 partition, int skip)
-{
-	ide_init_pc(pc);
-	pc->c[0] = POSITION_TO_ELEMENT;
-	pc->c[1] = 2;
-	put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
-	pc->c[8] = partition;
-	pc->flags |= PC_FLAG_WAIT_FOR_DSC;
-}
-
-static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-
-	if (tape->chrdev_dir != IDETAPE_DIR_READ)
-		return;
-
-	clear_bit(ilog2(IDE_AFLAG_FILEMARK), &drive->atapi_flags);
-	tape->valid = 0;
-	if (tape->buf != NULL) {
-		kfree(tape->buf);
-		tape->buf = NULL;
-	}
-
-	tape->chrdev_dir = IDETAPE_DIR_NONE;
-}
-
-/*
- * Position the tape to the requested block using the LOCATE packet command.
- * A READ POSITION command is then issued to check where we are positioned. Like
- * all higher level operations, we queue the commands at the tail of the request
- * queue and wait for their completion.
- */
-static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
-		u8 partition, int skip)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct gendisk *disk = tape->disk;
-	int ret;
-	struct ide_atapi_pc pc;
-
-	if (tape->chrdev_dir == IDETAPE_DIR_READ)
-		__ide_tape_discard_merge_buffer(drive);
-	idetape_wait_ready(drive, 60 * 5 * HZ);
-	idetape_create_locate_cmd(drive, &pc, block, partition, skip);
-	ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
-	if (ret)
-		return ret;
-
-	ret = ide_tape_read_position(drive);
-	if (ret < 0)
-		return ret;
-	return 0;
-}
-
-static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
-					  int restore_position)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	int seek, position;
-
-	__ide_tape_discard_merge_buffer(drive);
-	if (restore_position) {
-		position = ide_tape_read_position(drive);
-		seek = position > 0 ? position : 0;
-		if (idetape_position_tape(drive, seek, 0, 0)) {
-			printk(KERN_INFO "ide-tape: %s: position_tape failed in"
-					 " %s\n", tape->name, __func__);
-			return;
-		}
-	}
-}
-
-/*
- * Generate a read/write request for the block device interface and wait for it
- * to be serviced.
- */
-static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int size)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct request *rq;
-	int ret;
-
-	ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, size: %d", cmd, size);
-
-	BUG_ON(cmd != REQ_IDETAPE_READ && cmd != REQ_IDETAPE_WRITE);
-	BUG_ON(size < 0 || size % tape->blk_size);
-
-	rq = blk_get_request(drive->queue, REQ_OP_DRV_IN, 0);
-	ide_req(rq)->type = ATA_PRIV_MISC;
-	scsi_req(rq)->cmd[13] = cmd;
-	rq->rq_disk = tape->disk;
-	rq->__sector = tape->first_frame;
-
-	if (size) {
-		ret = blk_rq_map_kern(drive->queue, rq, tape->buf, size,
-				      GFP_NOIO);
-		if (ret)
-			goto out_put;
-	}
-
-	blk_execute_rq(tape->disk, rq, 0);
-
-	/* calculate the number of transferred bytes and update buffer state */
-	size -= scsi_req(rq)->resid_len;
-	tape->cur = tape->buf;
-	if (cmd == REQ_IDETAPE_READ)
-		tape->valid = size;
-	else
-		tape->valid = 0;
-
-	ret = size;
-	if (scsi_req(rq)->result == IDE_DRV_ERROR_GENERAL)
-		ret = -EIO;
-out_put:
-	blk_put_request(rq);
-	return ret;
-}
-
-static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
-{
-	ide_init_pc(pc);
-	pc->c[0] = INQUIRY;
-	pc->c[4] = 254;
-	pc->req_xfer = 254;
-}
-
-static void idetape_create_rewind_cmd(ide_drive_t *drive,
-		struct ide_atapi_pc *pc)
-{
-	ide_init_pc(pc);
-	pc->c[0] = REZERO_UNIT;
-	pc->flags |= PC_FLAG_WAIT_FOR_DSC;
-}
-
-static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
-{
-	ide_init_pc(pc);
-	pc->c[0] = ERASE;
-	pc->c[1] = 1;
-	pc->flags |= PC_FLAG_WAIT_FOR_DSC;
-}
-
-static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
-{
-	ide_init_pc(pc);
-	pc->c[0] = SPACE;
-	put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
-	pc->c[1] = cmd;
-	pc->flags |= PC_FLAG_WAIT_FOR_DSC;
-}
-
-static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-
-	if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
-		printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
-				" but we are not writing.\n");
-		return;
-	}
-	if (tape->buf) {
-		size_t aligned = roundup(tape->valid, tape->blk_size);
-
-		memset(tape->cur, 0, aligned - tape->valid);
-		idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, aligned);
-		kfree(tape->buf);
-		tape->buf = NULL;
-	}
-	tape->chrdev_dir = IDETAPE_DIR_NONE;
-}
-
-static int idetape_init_rw(ide_drive_t *drive, int dir)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	int rc;
-
-	BUG_ON(dir != IDETAPE_DIR_READ && dir != IDETAPE_DIR_WRITE);
-
-	if (tape->chrdev_dir == dir)
-		return 0;
-
-	if (tape->chrdev_dir == IDETAPE_DIR_READ)
-		ide_tape_discard_merge_buffer(drive, 1);
-	else if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
-		ide_tape_flush_merge_buffer(drive);
-		idetape_flush_tape_buffers(drive);
-	}
-
-	if (tape->buf || tape->valid) {
-		printk(KERN_ERR "ide-tape: valid should be 0 now\n");
-		tape->valid = 0;
-	}
-
-	tape->buf = kmalloc(tape->buffer_size, GFP_KERNEL);
-	if (!tape->buf)
-		return -ENOMEM;
-	tape->chrdev_dir = dir;
-	tape->cur = tape->buf;
-
-	/*
-	 * Issue a 0 rw command to ensure that DSC handshake is
-	 * switched from completion mode to buffer available mode.  No
-	 * point in issuing this if DSC overlap isn't supported, some
-	 * drives (Seagate STT3401A) will return an error.
-	 */
-	if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) {
-		int cmd = dir == IDETAPE_DIR_READ ? REQ_IDETAPE_READ
-						  : REQ_IDETAPE_WRITE;
-
-		rc = idetape_queue_rw_tail(drive, cmd, 0);
-		if (rc < 0) {
-			kfree(tape->buf);
-			tape->buf = NULL;
-			tape->chrdev_dir = IDETAPE_DIR_NONE;
-			return rc;
-		}
-	}
-
-	return 0;
-}
-
-static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
-{
-	idetape_tape_t *tape = drive->driver_data;
-
-	memset(tape->buf, 0, tape->buffer_size);
-
-	while (bcount) {
-		unsigned int count = min(tape->buffer_size, bcount);
-
-		idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, count);
-		bcount -= count;
-	}
-}
-
-/*
- * Rewinds the tape to the Beginning Of the current Partition (BOP). We
- * currently support only one partition.
- */
-static int idetape_rewind_tape(ide_drive_t *drive)
-{
-	struct ide_tape_obj *tape = drive->driver_data;
-	struct gendisk *disk = tape->disk;
-	struct ide_atapi_pc pc;
-	int ret;
-
-	ide_debug_log(IDE_DBG_FUNC, "enter");
-
-	idetape_create_rewind_cmd(drive, &pc);
-	ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
-	if (ret)
-		return ret;
-
-	ret = ide_tape_read_position(drive);
-	if (ret < 0)
-		return ret;
-	return 0;
-}
-
-/* mtio.h compatible commands should be issued to the chrdev interface. */
-static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
-				unsigned long arg)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	void __user *argp = (void __user *)arg;
-
-	struct idetape_config {
-		int dsc_rw_frequency;
-		int dsc_media_access_frequency;
-		int nr_stages;
-	} config;
-
-	ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%04x", cmd);
-
-	switch (cmd) {
-	case 0x0340:
-		if (copy_from_user(&config, argp, sizeof(config)))
-			return -EFAULT;
-		tape->best_dsc_rw_freq = config.dsc_rw_frequency;
-		break;
-	case 0x0350:
-		memset(&config, 0, sizeof(config));
-		config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
-		config.nr_stages = 1;
-		if (copy_to_user(argp, &config, sizeof(config)))
-			return -EFAULT;
-		break;
-	default:
-		return -EIO;
-	}
-	return 0;
-}
-
-static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
-					int mt_count)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct gendisk *disk = tape->disk;
-	struct ide_atapi_pc pc;
-	int retval, count = 0;
-	int sprev = !!(tape->caps[4] & 0x20);
-
-
-	ide_debug_log(IDE_DBG_FUNC, "mt_op: %d, mt_count: %d", mt_op, mt_count);
-
-	if (mt_count == 0)
-		return 0;
-	if (MTBSF == mt_op || MTBSFM == mt_op) {
-		if (!sprev)
-			return -EIO;
-		mt_count = -mt_count;
-	}
-
-	if (tape->chrdev_dir == IDETAPE_DIR_READ) {
-		tape->valid = 0;
-		if (test_and_clear_bit(ilog2(IDE_AFLAG_FILEMARK),
-				       &drive->atapi_flags))
-			++count;
-		ide_tape_discard_merge_buffer(drive, 0);
-	}
-
-	switch (mt_op) {
-	case MTFSF:
-	case MTBSF:
-		idetape_create_space_cmd(&pc, mt_count - count,
-					 IDETAPE_SPACE_OVER_FILEMARK);
-		return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
-	case MTFSFM:
-	case MTBSFM:
-		if (!sprev)
-			return -EIO;
-		retval = idetape_space_over_filemarks(drive, MTFSF,
-						      mt_count - count);
-		if (retval)
-			return retval;
-		count = (MTBSFM == mt_op ? 1 : -1);
-		return idetape_space_over_filemarks(drive, MTFSF, count);
-	default:
-		printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
-				mt_op);
-		return -EIO;
-	}
-}
-
-/*
- * Our character device read / write functions.
- *
- * The tape is optimized to maximize throughput when it is transferring an
- * integral number of the "continuous transfer limit", which is a parameter of
- * the specific tape (26kB on my particular tape, 32kB for Onstream).
- *
- * As of version 1.3 of the driver, the character device provides an abstract
- * continuous view of the media - any mix of block sizes (even 1 byte) on the
- * same backup/restore procedure is supported. The driver will internally
- * convert the requests to the recommended transfer unit, so that an unmatch
- * between the user's block size to the recommended size will only result in a
- * (slightly) increased driver overhead, but will no longer hit performance.
- * This is not applicable to Onstream.
- */
-static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
-				   size_t count, loff_t *ppos)
-{
-	struct ide_tape_obj *tape = file->private_data;
-	ide_drive_t *drive = tape->drive;
-	size_t done = 0;
-	ssize_t ret = 0;
-	int rc;
-
-	ide_debug_log(IDE_DBG_FUNC, "count %zd", count);
-
-	if (tape->chrdev_dir != IDETAPE_DIR_READ) {
-		if (test_bit(ilog2(IDE_AFLAG_DETECT_BS), &drive->atapi_flags))
-			if (count > tape->blk_size &&
-			    (count % tape->blk_size) == 0)
-				tape->user_bs_factor = count / tape->blk_size;
-	}
-
-	rc = idetape_init_rw(drive, IDETAPE_DIR_READ);
-	if (rc < 0)
-		return rc;
-
-	while (done < count) {
-		size_t todo;
-
-		/* refill if staging buffer is empty */
-		if (!tape->valid) {
-			/* If we are at a filemark, nothing more to read */
-			if (test_bit(ilog2(IDE_AFLAG_FILEMARK),
-				     &drive->atapi_flags))
-				break;
-			/* read */
-			if (idetape_queue_rw_tail(drive, REQ_IDETAPE_READ,
-						  tape->buffer_size) <= 0)
-				break;
-		}
-
-		/* copy out */
-		todo = min_t(size_t, count - done, tape->valid);
-		if (copy_to_user(buf + done, tape->cur, todo))
-			ret = -EFAULT;
-
-		tape->cur += todo;
-		tape->valid -= todo;
-		done += todo;
-	}
-
-	if (!done && test_bit(ilog2(IDE_AFLAG_FILEMARK), &drive->atapi_flags)) {
-		idetape_space_over_filemarks(drive, MTFSF, 1);
-		return 0;
-	}
-
-	return ret ? ret : done;
-}
-
-static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
-				     size_t count, loff_t *ppos)
-{
-	struct ide_tape_obj *tape = file->private_data;
-	ide_drive_t *drive = tape->drive;
-	size_t done = 0;
-	ssize_t ret = 0;
-	int rc;
-
-	/* The drive is write protected. */
-	if (tape->write_prot)
-		return -EACCES;
-
-	ide_debug_log(IDE_DBG_FUNC, "count %zd", count);
-
-	/* Initialize write operation */
-	rc = idetape_init_rw(drive, IDETAPE_DIR_WRITE);
-	if (rc < 0)
-		return rc;
-
-	while (done < count) {
-		size_t todo;
-
-		/* flush if staging buffer is full */
-		if (tape->valid == tape->buffer_size &&
-		    idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
-					  tape->buffer_size) <= 0)
-			return rc;
-
-		/* copy in */
-		todo = min_t(size_t, count - done,
-			     tape->buffer_size - tape->valid);
-		if (copy_from_user(tape->cur, buf + done, todo))
-			ret = -EFAULT;
-
-		tape->cur += todo;
-		tape->valid += todo;
-		done += todo;
-	}
-
-	return ret ? ret : done;
-}
-
-static int idetape_write_filemark(ide_drive_t *drive)
-{
-	struct ide_tape_obj *tape = drive->driver_data;
-	struct ide_atapi_pc pc;
-
-	/* Write a filemark */
-	idetape_create_write_filemark_cmd(drive, &pc, 1);
-	if (ide_queue_pc_tail(drive, tape->disk, &pc, NULL, 0)) {
-		printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
-		return -EIO;
-	}
-	return 0;
-}
-
-/*
- * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
- * requested.
- *
- * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
- * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
- * usually not supported.
- *
- * The following commands are currently not supported:
- *
- * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
- * MT_ST_WRITE_THRESHOLD.
- */
-static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct gendisk *disk = tape->disk;
-	struct ide_atapi_pc pc;
-	int i, retval;
-
-	ide_debug_log(IDE_DBG_FUNC, "MTIOCTOP ioctl: mt_op: %d, mt_count: %d",
-		      mt_op, mt_count);
-
-	switch (mt_op) {
-	case MTFSF:
-	case MTFSFM:
-	case MTBSF:
-	case MTBSFM:
-		if (!mt_count)
-			return 0;
-		return idetape_space_over_filemarks(drive, mt_op, mt_count);
-	default:
-		break;
-	}
-
-	switch (mt_op) {
-	case MTWEOF:
-		if (tape->write_prot)
-			return -EACCES;
-		ide_tape_discard_merge_buffer(drive, 1);
-		for (i = 0; i < mt_count; i++) {
-			retval = idetape_write_filemark(drive);
-			if (retval)
-				return retval;
-		}
-		return 0;
-	case MTREW:
-		ide_tape_discard_merge_buffer(drive, 0);
-		if (idetape_rewind_tape(drive))
-			return -EIO;
-		return 0;
-	case MTLOAD:
-		ide_tape_discard_merge_buffer(drive, 0);
-		return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
-	case MTUNLOAD:
-	case MTOFFL:
-		/*
-		 * If door is locked, attempt to unlock before
-		 * attempting to eject.
-		 */
-		if (tape->door_locked) {
-			if (!ide_set_media_lock(drive, disk, 0))
-				tape->door_locked = DOOR_UNLOCKED;
-		}
-		ide_tape_discard_merge_buffer(drive, 0);
-		retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK);
-		if (!retval)
-			clear_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT),
-				  &drive->atapi_flags);
-		return retval;
-	case MTNOP:
-		ide_tape_discard_merge_buffer(drive, 0);
-		return idetape_flush_tape_buffers(drive);
-	case MTRETEN:
-		ide_tape_discard_merge_buffer(drive, 0);
-		return ide_do_start_stop(drive, disk,
-			IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
-	case MTEOM:
-		idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
-		return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
-	case MTERASE:
-		(void)idetape_rewind_tape(drive);
-		idetape_create_erase_cmd(&pc);
-		return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
-	case MTSETBLK:
-		if (mt_count) {
-			if (mt_count < tape->blk_size ||
-			    mt_count % tape->blk_size)
-				return -EIO;
-			tape->user_bs_factor = mt_count / tape->blk_size;
-			clear_bit(ilog2(IDE_AFLAG_DETECT_BS),
-				  &drive->atapi_flags);
-		} else
-			set_bit(ilog2(IDE_AFLAG_DETECT_BS),
-				&drive->atapi_flags);
-		return 0;
-	case MTSEEK:
-		ide_tape_discard_merge_buffer(drive, 0);
-		return idetape_position_tape(drive,
-			mt_count * tape->user_bs_factor, tape->partition, 0);
-	case MTSETPART:
-		ide_tape_discard_merge_buffer(drive, 0);
-		return idetape_position_tape(drive, 0, mt_count, 0);
-	case MTFSR:
-	case MTBSR:
-	case MTLOCK:
-		retval = ide_set_media_lock(drive, disk, 1);
-		if (retval)
-			return retval;
-		tape->door_locked = DOOR_EXPLICITLY_LOCKED;
-		return 0;
-	case MTUNLOCK:
-		retval = ide_set_media_lock(drive, disk, 0);
-		if (retval)
-			return retval;
-		tape->door_locked = DOOR_UNLOCKED;
-		return 0;
-	default:
-		printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
-				mt_op);
-		return -EIO;
-	}
-}
-
-/*
- * Our character device ioctls. General mtio.h magnetic io commands are
- * supported here, and not in the corresponding block interface. Our own
- * ide-tape ioctls are supported on both interfaces.
- */
-static long do_idetape_chrdev_ioctl(struct file *file,
-				unsigned int cmd, unsigned long arg)
-{
-	struct ide_tape_obj *tape = file->private_data;
-	ide_drive_t *drive = tape->drive;
-	struct mtop mtop;
-	struct mtget mtget;
-	struct mtpos mtpos;
-	int block_offset = 0, position = tape->first_frame;
-	void __user *argp = (void __user *)arg;
-
-	ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x", cmd);
-
-	if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
-		ide_tape_flush_merge_buffer(drive);
-		idetape_flush_tape_buffers(drive);
-	}
-	if (cmd == MTIOCGET || cmd == MTIOCPOS) {
-		block_offset = tape->valid /
-			(tape->blk_size * tape->user_bs_factor);
-		position = ide_tape_read_position(drive);
-		if (position < 0)
-			return -EIO;
-	}
-	switch (cmd) {
-	case MTIOCTOP:
-		if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
-			return -EFAULT;
-		return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
-	case MTIOCGET:
-		memset(&mtget, 0, sizeof(struct mtget));
-		mtget.mt_type = MT_ISSCSI2;
-		mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
-		mtget.mt_dsreg =
-			((tape->blk_size * tape->user_bs_factor)
-			 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
-
-		if (tape->drv_write_prot)
-			mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
-
-		return put_user_mtget(argp, &mtget);
-	case MTIOCPOS:
-		mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
-		return put_user_mtpos(argp, &mtpos);
-	default:
-		if (tape->chrdev_dir == IDETAPE_DIR_READ)
-			ide_tape_discard_merge_buffer(drive, 1);
-		return idetape_blkdev_ioctl(drive, cmd, arg);
-	}
-}
-
-static long idetape_chrdev_ioctl(struct file *file,
-				unsigned int cmd, unsigned long arg)
-{
-	long ret;
-	mutex_lock(&ide_tape_mutex);
-	ret = do_idetape_chrdev_ioctl(file, cmd, arg);
-	mutex_unlock(&ide_tape_mutex);
-	return ret;
-}
-
-static long idetape_chrdev_compat_ioctl(struct file *file,
-				unsigned int cmd, unsigned long arg)
-{
-	long ret;
-
-	if (cmd == MTIOCPOS32)
-		cmd = MTIOCPOS;
-	else if (cmd == MTIOCGET32)
-		cmd = MTIOCGET;
-
-	mutex_lock(&ide_tape_mutex);
-	ret = do_idetape_chrdev_ioctl(file, cmd, arg);
-	mutex_unlock(&ide_tape_mutex);
-	return ret;
-}
-
-/*
- * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
- * block size with the reported value.
- */
-static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct ide_atapi_pc pc;
-	u8 buf[12];
-
-	idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
-	if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer)) {
-		printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
-		if (tape->blk_size == 0) {
-			printk(KERN_WARNING "ide-tape: Cannot deal with zero "
-					    "block size, assuming 32k\n");
-			tape->blk_size = 32768;
-		}
-		return;
-	}
-	tape->blk_size = (buf[4 + 5] << 16) +
-				(buf[4 + 6] << 8)  +
-				 buf[4 + 7];
-	tape->drv_write_prot = (buf[2] & 0x80) >> 7;
-
-	ide_debug_log(IDE_DBG_FUNC, "blk_size: %d, write_prot: %d",
-		      tape->blk_size, tape->drv_write_prot);
-}
-
-static int idetape_chrdev_open(struct inode *inode, struct file *filp)
-{
-	unsigned int minor = iminor(inode), i = minor & ~0xc0;
-	ide_drive_t *drive;
-	idetape_tape_t *tape;
-	int retval;
-
-	if (i >= MAX_HWIFS * MAX_DRIVES)
-		return -ENXIO;
-
-	mutex_lock(&idetape_chrdev_mutex);
-
-	tape = ide_tape_get(NULL, true, i);
-	if (!tape) {
-		mutex_unlock(&idetape_chrdev_mutex);
-		return -ENXIO;
-	}
-
-	drive = tape->drive;
-	filp->private_data = tape;
-
-	ide_debug_log(IDE_DBG_FUNC, "enter");
-
-	/*
-	 * We really want to do nonseekable_open(inode, filp); here, but some
-	 * versions of tar incorrectly call lseek on tapes and bail out if that
-	 * fails.  So we disallow pread() and pwrite(), but permit lseeks.
-	 */
-	filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
-
-
-	if (test_and_set_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags)) {
-		retval = -EBUSY;
-		goto out_put_tape;
-	}
-
-	retval = idetape_wait_ready(drive, 60 * HZ);
-	if (retval) {
-		clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
-		printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
-		goto out_put_tape;
-	}
-
-	ide_tape_read_position(drive);
-	if (!test_bit(ilog2(IDE_AFLAG_ADDRESS_VALID), &drive->atapi_flags))
-		(void)idetape_rewind_tape(drive);
-
-	/* Read block size and write protect status from drive. */
-	ide_tape_get_bsize_from_bdesc(drive);
-
-	/* Set write protect flag if device is opened as read-only. */
-	if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
-		tape->write_prot = 1;
-	else
-		tape->write_prot = tape->drv_write_prot;
-
-	/* Make sure drive isn't write protected if user wants to write. */
-	if (tape->write_prot) {
-		if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
-		    (filp->f_flags & O_ACCMODE) == O_RDWR) {
-			clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
-			retval = -EROFS;
-			goto out_put_tape;
-		}
-	}
-
-	/* Lock the tape drive door so user can't eject. */
-	if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
-		if (!ide_set_media_lock(drive, tape->disk, 1)) {
-			if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
-				tape->door_locked = DOOR_LOCKED;
-		}
-	}
-	mutex_unlock(&idetape_chrdev_mutex);
-
-	return 0;
-
-out_put_tape:
-	ide_tape_put(tape);
-
-	mutex_unlock(&idetape_chrdev_mutex);
-
-	return retval;
-}
-
-static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
-{
-	idetape_tape_t *tape = drive->driver_data;
-
-	ide_tape_flush_merge_buffer(drive);
-	tape->buf = kmalloc(tape->buffer_size, GFP_KERNEL);
-	if (tape->buf != NULL) {
-		idetape_pad_zeros(drive, tape->blk_size *
-				(tape->user_bs_factor - 1));
-		kfree(tape->buf);
-		tape->buf = NULL;
-	}
-	idetape_write_filemark(drive);
-	idetape_flush_tape_buffers(drive);
-	idetape_flush_tape_buffers(drive);
-}
-
-static int idetape_chrdev_release(struct inode *inode, struct file *filp)
-{
-	struct ide_tape_obj *tape = filp->private_data;
-	ide_drive_t *drive = tape->drive;
-	unsigned int minor = iminor(inode);
-
-	mutex_lock(&idetape_chrdev_mutex);
-
-	tape = drive->driver_data;
-
-	ide_debug_log(IDE_DBG_FUNC, "enter");
-
-	if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
-		idetape_write_release(drive, minor);
-	if (tape->chrdev_dir == IDETAPE_DIR_READ) {
-		if (minor < 128)
-			ide_tape_discard_merge_buffer(drive, 1);
-	}
-
-	if (minor < 128 && test_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT),
-				    &drive->atapi_flags))
-		(void) idetape_rewind_tape(drive);
-
-	if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
-		if (tape->door_locked == DOOR_LOCKED) {
-			if (!ide_set_media_lock(drive, tape->disk, 0))
-				tape->door_locked = DOOR_UNLOCKED;
-		}
-	}
-	clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
-	ide_tape_put(tape);
-
-	mutex_unlock(&idetape_chrdev_mutex);
-
-	return 0;
-}
-
-static void idetape_get_inquiry_results(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct ide_atapi_pc pc;
-	u8 pc_buf[256];
-	char fw_rev[4], vendor_id[8], product_id[16];
-
-	idetape_create_inquiry_cmd(&pc);
-	if (ide_queue_pc_tail(drive, tape->disk, &pc, pc_buf, pc.req_xfer)) {
-		printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
-				tape->name);
-		return;
-	}
-	memcpy(vendor_id, &pc_buf[8], 8);
-	memcpy(product_id, &pc_buf[16], 16);
-	memcpy(fw_rev, &pc_buf[32], 4);
-
-	ide_fixstring(vendor_id, 8, 0);
-	ide_fixstring(product_id, 16, 0);
-	ide_fixstring(fw_rev, 4, 0);
-
-	printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n",
-			drive->name, tape->name, vendor_id, product_id, fw_rev);
-}
-
-/*
- * Ask the tape about its various parameters. In particular, we will adjust our
- * data transfer buffer	size to the recommended value as returned by the tape.
- */
-static void idetape_get_mode_sense_results(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-	struct ide_atapi_pc pc;
-	u8 buf[24], *caps;
-	u8 speed, max_speed;
-
-	idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
-	if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer)) {
-		printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
-				" some default values\n");
-		tape->blk_size = 512;
-		put_unaligned(52,   (u16 *)&tape->caps[12]);
-		put_unaligned(540,  (u16 *)&tape->caps[14]);
-		put_unaligned(6*52, (u16 *)&tape->caps[16]);
-		return;
-	}
-	caps = buf + 4 + buf[3];
-
-	/* convert to host order and save for later use */
-	speed = be16_to_cpup((__be16 *)&caps[14]);
-	max_speed = be16_to_cpup((__be16 *)&caps[8]);
-
-	*(u16 *)&caps[8] = max_speed;
-	*(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]);
-	*(u16 *)&caps[14] = speed;
-	*(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]);
-
-	if (!speed) {
-		printk(KERN_INFO "ide-tape: %s: invalid tape speed "
-				"(assuming 650KB/sec)\n", drive->name);
-		*(u16 *)&caps[14] = 650;
-	}
-	if (!max_speed) {
-		printk(KERN_INFO "ide-tape: %s: invalid max_speed "
-				"(assuming 650KB/sec)\n", drive->name);
-		*(u16 *)&caps[8] = 650;
-	}
-
-	memcpy(&tape->caps, caps, 20);
-
-	/* device lacks locking support according to capabilities page */
-	if ((caps[6] & 1) == 0)
-		drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING;
-
-	if (caps[7] & 0x02)
-		tape->blk_size = 512;
-	else if (caps[7] & 0x04)
-		tape->blk_size = 1024;
-}
-
-#ifdef CONFIG_IDE_PROC_FS
-#define ide_tape_devset_get(name, field) \
-static int get_##name(ide_drive_t *drive) \
-{ \
-	idetape_tape_t *tape = drive->driver_data; \
-	return tape->field; \
-}
-
-#define ide_tape_devset_set(name, field) \
-static int set_##name(ide_drive_t *drive, int arg) \
-{ \
-	idetape_tape_t *tape = drive->driver_data; \
-	tape->field = arg; \
-	return 0; \
-}
-
-#define ide_tape_devset_rw_field(_name, _field) \
-ide_tape_devset_get(_name, _field) \
-ide_tape_devset_set(_name, _field) \
-IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name)
-
-#define ide_tape_devset_r_field(_name, _field) \
-ide_tape_devset_get(_name, _field) \
-IDE_DEVSET(_name, 0, get_##_name, NULL)
-
-static int mulf_tdsc(ide_drive_t *drive)	{ return 1000; }
-static int divf_tdsc(ide_drive_t *drive)	{ return   HZ; }
-static int divf_buffer(ide_drive_t *drive)	{ return    2; }
-static int divf_buffer_size(ide_drive_t *drive)	{ return 1024; }
-
-ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP);
-
-ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq);
-
-ide_tape_devset_r_field(avg_speed, avg_speed);
-ide_tape_devset_r_field(speed, caps[14]);
-ide_tape_devset_r_field(buffer, caps[16]);
-ide_tape_devset_r_field(buffer_size, buffer_size);
-
-static const struct ide_proc_devset idetape_settings[] = {
-	__IDE_PROC_DEVSET(avg_speed,	0, 0xffff, NULL, NULL),
-	__IDE_PROC_DEVSET(buffer,	0, 0xffff, NULL, divf_buffer),
-	__IDE_PROC_DEVSET(buffer_size,	0, 0xffff, NULL, divf_buffer_size),
-	__IDE_PROC_DEVSET(dsc_overlap,	0,      1, NULL, NULL),
-	__IDE_PROC_DEVSET(speed,	0, 0xffff, NULL, NULL),
-	__IDE_PROC_DEVSET(tdsc,		IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX,
-					mulf_tdsc, divf_tdsc),
-	{ NULL },
-};
-#endif
-
-/*
- * The function below is called to:
- *
- * 1. Initialize our various state variables.
- * 2. Ask the tape for its capabilities.
- * 3. Allocate a buffer which will be used for data transfer. The buffer size
- * is chosen based on the recommendation which we received in step 2.
- *
- * Note that at this point ide.c already assigned us an irq, so that we can
- * queue requests here and wait for their completion.
- */
-static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
-{
-	unsigned long t;
-	int speed;
-	u16 *ctl = (u16 *)&tape->caps[12];
-
-	ide_debug_log(IDE_DBG_FUNC, "minor: %d", minor);
-
-	drive->pc_callback = ide_tape_callback;
-
-	drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP;
-
-	if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
-		printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
-				 tape->name);
-		drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
-	}
-
-	/* Seagate Travan drives do not support DSC overlap. */
-	if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401"))
-		drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
-
-	tape->minor = minor;
-	tape->name[0] = 'h';
-	tape->name[1] = 't';
-	tape->name[2] = '0' + minor;
-	tape->chrdev_dir = IDETAPE_DIR_NONE;
-
-	idetape_get_inquiry_results(drive);
-	idetape_get_mode_sense_results(drive);
-	ide_tape_get_bsize_from_bdesc(drive);
-	tape->user_bs_factor = 1;
-	tape->buffer_size = *ctl * tape->blk_size;
-	while (tape->buffer_size > 0xffff) {
-		printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
-		*ctl /= 2;
-		tape->buffer_size = *ctl * tape->blk_size;
-	}
-
-	/* select the "best" DSC read/write polling freq */
-	speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
-
-	t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
-
-	/*
-	 * Ensure that the number we got makes sense; limit it within
-	 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
-	 */
-	tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
-					 IDETAPE_DSC_RW_MAX);
-	printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
-		"%ums tDSC%s\n",
-		drive->name, tape->name, *(u16 *)&tape->caps[14],
-		(*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
-		tape->buffer_size / 1024,
-		jiffies_to_msecs(tape->best_dsc_rw_freq),
-		(drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");
-
-	ide_proc_register_driver(drive, tape->driver);
-}
-
-static void ide_tape_remove(ide_drive_t *drive)
-{
-	idetape_tape_t *tape = drive->driver_data;
-
-	ide_proc_unregister_driver(drive, tape->driver);
-	device_del(&tape->dev);
-
-	mutex_lock(&idetape_ref_mutex);
-	put_device(&tape->dev);
-	mutex_unlock(&idetape_ref_mutex);
-}
-
-static void ide_tape_release(struct device *dev)
-{
-	struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj);
-	ide_drive_t *drive = tape->drive;
-	struct gendisk *g = tape->disk;
-
-	BUG_ON(tape->valid);
-
-	drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
-	drive->driver_data = NULL;
-	device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
-	device_destroy(idetape_sysfs_class,
-			MKDEV(IDETAPE_MAJOR, tape->minor + 128));
-	idetape_devs[tape->minor] = NULL;
-	g->private_data = NULL;
-	put_disk(g);
-	kfree(tape);
-}
-
-#ifdef CONFIG_IDE_PROC_FS
-static int idetape_name_proc_show(struct seq_file *m, void *v)
-{
-	ide_drive_t	*drive = (ide_drive_t *) m->private;
-	idetape_tape_t	*tape = drive->driver_data;
-
-	seq_printf(m, "%s\n", tape->name);
-	return 0;
-}
-
-static ide_proc_entry_t idetape_proc[] = {
-	{ "capacity",	S_IFREG|S_IRUGO,	ide_capacity_proc_show	},
-	{ "name",	S_IFREG|S_IRUGO,	idetape_name_proc_show	},
-	{}
-};
-
-static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive)
-{
-	return idetape_proc;
-}
-
-static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive)
-{
-	return idetape_settings;
-}
-#endif
-
-static int ide_tape_probe(ide_drive_t *);
-
-static struct ide_driver idetape_driver = {
-	.gen_driver = {
-		.owner		= THIS_MODULE,
-		.name		= "ide-tape",
-		.bus		= &ide_bus_type,
-	},
-	.probe			= ide_tape_probe,
-	.remove			= ide_tape_remove,
-	.version		= IDETAPE_VERSION,
-	.do_request		= idetape_do_request,
-#ifdef CONFIG_IDE_PROC_FS
-	.proc_entries		= ide_tape_proc_entries,
-	.proc_devsets		= ide_tape_proc_devsets,
-#endif
-};
-
-/* Our character device supporting functions, passed to register_chrdev. */
-static const struct file_operations idetape_fops = {
-	.owner		= THIS_MODULE,
-	.read		= idetape_chrdev_read,
-	.write		= idetape_chrdev_write,
-	.unlocked_ioctl	= idetape_chrdev_ioctl,
-	.compat_ioctl	= IS_ENABLED(CONFIG_COMPAT) ?
-			  idetape_chrdev_compat_ioctl : NULL,
-	.open		= idetape_chrdev_open,
-	.release	= idetape_chrdev_release,
-	.llseek		= noop_llseek,
-};
-
-static int idetape_open(struct block_device *bdev, fmode_t mode)
-{
-	struct ide_tape_obj *tape;
-
-	mutex_lock(&ide_tape_mutex);
-	tape = ide_tape_get(bdev->bd_disk, false, 0);
-	mutex_unlock(&ide_tape_mutex);
-
-	if (!tape)
-		return -ENXIO;
-
-	return 0;
-}
-
-static void idetape_release(struct gendisk *disk, fmode_t mode)
-{
-	struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj);
-
-	mutex_lock(&ide_tape_mutex);
-	ide_tape_put(tape);
-	mutex_unlock(&ide_tape_mutex);
-}
-
-static int idetape_ioctl(struct block_device *bdev, fmode_t mode,
-			unsigned int cmd, unsigned long arg)
-{
-	struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj);
-	ide_drive_t *drive = tape->drive;
-	int err;
-
-	mutex_lock(&ide_tape_mutex);
-	err = generic_ide_ioctl(drive, bdev, cmd, arg);
-	if (err == -EINVAL)
-		err = idetape_blkdev_ioctl(drive, cmd, arg);
-	mutex_unlock(&ide_tape_mutex);
-
-	return err;
-}
-
-static int idetape_compat_ioctl(struct block_device *bdev, fmode_t mode,
-				unsigned int cmd, unsigned long arg)
-{
-        if (cmd == 0x0340 || cmd == 0x350)
-		arg = (unsigned long)compat_ptr(arg);
-
-	return idetape_ioctl(bdev, mode, cmd, arg);
-}
-
-static const struct block_device_operations idetape_block_ops = {
-	.owner		= THIS_MODULE,
-	.open		= idetape_open,
-	.release	= idetape_release,
-	.ioctl		= idetape_ioctl,
-	.compat_ioctl	= IS_ENABLED(CONFIG_COMPAT) ?
-				idetape_compat_ioctl : NULL,
-};
-
-static int ide_tape_probe(ide_drive_t *drive)
-{
-	idetape_tape_t *tape;
-	struct gendisk *g;
-	int minor;
-
-	ide_debug_log(IDE_DBG_FUNC, "enter");
-
-	if (!strstr(DRV_NAME, drive->driver_req))
-		goto failed;
-
-	if (drive->media != ide_tape)
-		goto failed;
-
-	if ((drive->dev_flags & IDE_DFLAG_ID_READ) &&
-	    ide_check_atapi_device(drive, DRV_NAME) == 0) {
-		printk(KERN_ERR "ide-tape: %s: not supported by this version of"
-				" the driver\n", drive->name);
-		goto failed;
-	}
-	tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
-	if (tape == NULL) {
-		printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
-				drive->name);
-		goto failed;
-	}
-
-	g = alloc_disk(1 << PARTN_BITS);
-	if (!g)
-		goto out_free_tape;
-
-	ide_init_disk(g, drive);
-
-	tape->dev.parent = &drive->gendev;
-	tape->dev.release = ide_tape_release;
-	dev_set_name(&tape->dev, "%s", dev_name(&drive->gendev));
-
-	if (device_register(&tape->dev))
-		goto out_free_disk;
-
-	tape->drive = drive;
-	tape->driver = &idetape_driver;
-	tape->disk = g;
-
-	g->private_data = &tape->driver;
-
-	drive->driver_data = tape;
-
-	mutex_lock(&idetape_ref_mutex);
-	for (minor = 0; idetape_devs[minor]; minor++)
-		;
-	idetape_devs[minor] = tape;
-	mutex_unlock(&idetape_ref_mutex);
-
-	idetape_setup(drive, tape, minor);
-
-	device_create(idetape_sysfs_class, &drive->gendev,
-		      MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name);
-	device_create(idetape_sysfs_class, &drive->gendev,
-		      MKDEV(IDETAPE_MAJOR, minor + 128), NULL,
-		      "n%s", tape->name);
-
-	g->fops = &idetape_block_ops;
-
-	return 0;
-
-out_free_disk:
-	put_disk(g);
-out_free_tape:
-	kfree(tape);
-failed:
-	return -ENODEV;
-}
-
-static void __exit idetape_exit(void)
-{
-	driver_unregister(&idetape_driver.gen_driver);
-	class_destroy(idetape_sysfs_class);
-	unregister_chrdev(IDETAPE_MAJOR, "ht");
-}
-
-static int __init idetape_init(void)
-{
-	int error = 1;
-	idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
-	if (IS_ERR(idetape_sysfs_class)) {
-		idetape_sysfs_class = NULL;
-		printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
-		error = -EBUSY;
-		goto out;
-	}
-
-	if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
-		printk(KERN_ERR "ide-tape: Failed to register chrdev"
-				" interface\n");
-		error = -EBUSY;
-		goto out_free_class;
-	}
-
-	error = driver_register(&idetape_driver.gen_driver);
-	if (error)
-		goto out_free_chrdev;
-
-	return 0;
-
-out_free_chrdev:
-	unregister_chrdev(IDETAPE_MAJOR, "ht");
-out_free_class:
-	class_destroy(idetape_sysfs_class);
-out:
-	return error;
-}
-
-MODULE_ALIAS("ide:*m-tape*");
-module_init(idetape_init);
-module_exit(idetape_exit);
-MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
-MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
-MODULE_LICENSE("GPL");