/*

   * ATAPI CD-ROM driver.

   *

   * Copyright (C) 1994-1996   Scott Snyder <snyder@fnald0.fnal.gov>
   * Copyright (C) 1996-1998   Erik Andersen <andersee@debian.org>
   * Copyright (C) 1998-2000   Jens Axboe <axboe@suse.de>

   * Copyright (C) 2005, 2007-2009  Bartlomiej Zolnierkiewicz

   *
   * May be copied or modified under the terms of the GNU General Public
   * License.  See linux/COPYING for more information.
   *

   * See Documentation/cdrom/ide-cd for usage information.
   *
   * Suggestions are welcome. Patches that work are more welcome though. ;-)

   *
   * Documentation:
   *	Mt. Fuji (SFF8090 version 4) and ATAPI (SFF-8020i rev 2.6) standards.

   *

   * For historical changelog please see:
   *	Documentation/ide/ChangeLog.ide-cd.1994-2004
   */

  #define DRV_NAME "ide-cd"
  #define PFX DRV_NAME ": "

  #define IDECD_VERSION "5.00"

  #include <linux/module.h>
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/delay.h>
  #include <linux/timer.h>

  #include <linux/seq_file.h>

  #include <linux/slab.h>
  #include <linux/interrupt.h>
  #include <linux/errno.h>
  #include <linux/cdrom.h>
  #include <linux/ide.h>
  #include <linux/completion.h>

  #include <linux/mutex.h>

  #include <linux/bcd.h>

  /* For SCSI -> ATAPI command conversion */
  #include <scsi/scsi.h>

  #include <linux/io.h>

  #include <asm/byteorder.h>

  #include <linux/uaccess.h>

  #include <asm/unaligned.h>
  
  #include "ide-cd.h"

  static DEFINE_MUTEX(ide_cd_mutex);

  static DEFINE_MUTEX(idecd_ref_mutex);

  static void ide_cd_release(struct device *);

  static struct cdrom_info *ide_cd_get(struct gendisk *disk)
  {
  	struct cdrom_info *cd = NULL;

  	mutex_lock(&idecd_ref_mutex);

  	cd = ide_drv_g(disk, cdrom_info);

  	if (cd) {

  		if (ide_device_get(cd->drive))

  			cd = NULL;

  		else

  			get_device(&cd->dev);

  	}

  	mutex_unlock(&idecd_ref_mutex);

  	return cd;
  }

  static void ide_cd_put(struct cdrom_info *cd)
  {

  	ide_drive_t *drive = cd->drive;

  	mutex_lock(&idecd_ref_mutex);

  	put_device(&cd->dev);

  	ide_device_put(drive);

  	mutex_unlock(&idecd_ref_mutex);

  }

  /*

   * Generic packet command support and error handling routines.
   */

  /* Mark that we've seen a media change and invalidate our internal buffers. */

  static void cdrom_saw_media_change(ide_drive_t *drive)

  {

  	drive->dev_flags |= IDE_DFLAG_MEDIA_CHANGED;

  	drive->atapi_flags &= ~IDE_AFLAG_TOC_VALID;

  }

  static int cdrom_log_sense(ide_drive_t *drive, struct request *rq)

  {

  	struct request_sense *sense = &drive->sense_data;

  	int log = 0;

  	if (!sense || !rq || (rq->cmd_flags & REQ_QUIET))

  		return 0;

  	ide_debug_log(IDE_DBG_SENSE, "sense_key: 0x%x", sense->sense_key);

  	switch (sense->sense_key) {

  	case NO_SENSE:
  	case RECOVERED_ERROR:
  		break;
  	case NOT_READY:
  		/*

  		 * don't care about tray state messages for e.g. capacity
  		 * commands or in-progress or becoming ready

  		 */
  		if (sense->asc == 0x3a || sense->asc == 0x04)

  			break;

  		log = 1;
  		break;
  	case ILLEGAL_REQUEST:
  		/*

  		 * don't log START_STOP unit with LoEj set, since we cannot
  		 * reliably check if drive can auto-close

  		 */
  		if (rq->cmd[0] == GPCMD_START_STOP_UNIT && sense->asc == 0x24)

  			break;

  		log = 1;
  		break;
  	case UNIT_ATTENTION:
  		/*

  		 * Make good and sure we've seen this potential media change.
  		 * Some drives (i.e. Creative) fail to present the correct sense
  		 * key in the error register.

  		 */
  		cdrom_saw_media_change(drive);
  		break;
  	default:
  		log = 1;
  		break;

  	}
  	return log;
  }

  static void cdrom_analyze_sense_data(ide_drive_t *drive,

  				     struct request *failed_command)

  {

  	struct request_sense *sense = &drive->sense_data;
  	struct cdrom_info *info = drive->driver_data;

  	unsigned long sector;
  	unsigned long bio_sectors;

  	ide_debug_log(IDE_DBG_SENSE, "error_code: 0x%x, sense_key: 0x%x",
  				     sense->error_code, sense->sense_key);

  
  	if (failed_command)

  		ide_debug_log(IDE_DBG_SENSE, "failed cmd: 0x%x",
  					     failed_command->cmd[0]);

  	if (!cdrom_log_sense(drive, failed_command))

  		return;
  
  	/*

  	 * If a read toc is executed for a CD-R or CD-RW medium where the first
  	 * toc has not been recorded yet, it will fail with 05/24/00 (which is a
  	 * confusing error)

  	 */
  	if (failed_command && failed_command->cmd[0] == GPCMD_READ_TOC_PMA_ATIP)
  		if (sense->sense_key == 0x05 && sense->asc == 0x24)
  			return;

  	/* current error */
  	if (sense->error_code == 0x70) {

  		switch (sense->sense_key) {

  		case MEDIUM_ERROR:
  		case VOLUME_OVERFLOW:
  		case ILLEGAL_REQUEST:
  			if (!sense->valid)
  				break;
  			if (failed_command == NULL ||

  			    failed_command->cmd_type != REQ_TYPE_FS)

  				break;
  			sector = (sense->information[0] << 24) |
  				 (sense->information[1] << 16) |
  				 (sense->information[2] <<  8) |
  				 (sense->information[3]);

  			if (queue_logical_block_size(drive->queue) == 2048)

  				/* device sector size is 2K */
  				sector <<= 2;

  
  			bio_sectors = max(bio_sectors(failed_command->bio), 4U);

  			sector &= ~(bio_sectors - 1);

  			/*
  			 * The SCSI specification allows for the value
  			 * returned by READ CAPACITY to be up to 75 2K
  			 * sectors past the last readable block.
  			 * Therefore, if we hit a medium error within the
  			 * last 75 2K sectors, we decrease the saved size
  			 * value.
  			 */

  			if (sector < get_capacity(info->disk) &&

  			    drive->probed_capacity - sector < 4 * 75)

  				set_capacity(info->disk, sector);

  		}
  	}

  	ide_cd_log_error(drive->name, failed_command, sense);

  }

  static void ide_cd_complete_failed_rq(ide_drive_t *drive, struct request *rq)
  {
  	/*

  	 * For REQ_TYPE_SENSE, "rq->special" points to the original

  	 * failed request.  Also, the sense data should be read
  	 * directly from rq which might be different from the original
  	 * sense buffer if it got copied during mapping.

  	 */

  	struct request *failed = (struct request *)rq->special;

  	void *sense = bio_data(rq->bio);

  
  	if (failed) {
  		if (failed->sense) {

  			/*
  			 * Sense is always read into drive->sense_data.
  			 * Copy back if the failed request has its
  			 * sense pointer set.
  			 */
  			memcpy(failed->sense, sense, 18);

  			failed->sense_len = rq->sense_len;
  		}

  		cdrom_analyze_sense_data(drive, failed);

  
  		if (ide_end_rq(drive, failed, -EIO, blk_rq_bytes(failed)))
  			BUG();
  	} else

  		cdrom_analyze_sense_data(drive, NULL);

  }

  /*

   * Allow the drive 5 seconds to recover; some devices will return NOT_READY
   * while flushing data from cache.
   *
   * returns: 0 failed (write timeout expired)
   *	    1 success
   */
  static int ide_cd_breathe(ide_drive_t *drive, struct request *rq)
  {
  
  	struct cdrom_info *info = drive->driver_data;
  
  	if (!rq->errors)
  		info->write_timeout = jiffies +	ATAPI_WAIT_WRITE_BUSY;
  
  	rq->errors = 1;
  
  	if (time_after(jiffies, info->write_timeout))
  		return 0;
  	else {

  		/*

  		 * take a breather

  		 */

  		blk_delay_queue(drive->queue, 1);

  		return 1;
  	}
  }
  
  /**

   * Returns:
   * 0: if the request should be continued.

   * 1: if the request will be going through error recovery.
   * 2: if the request should be ended.

   */

  static int cdrom_decode_status(ide_drive_t *drive, u8 stat)

  {

  	ide_hwif_t *hwif = drive->hwif;

  	struct request *rq = hwif->rq;

  	int err, sense_key, do_end_request = 0;

  	/* get the IDE error register */

  	err = ide_read_error(drive);

  	sense_key = err >> 4;

  	ide_debug_log(IDE_DBG_RQ, "cmd: 0x%x, rq->cmd_type: 0x%x, err: 0x%x, "
  				  "stat 0x%x",
  				  rq->cmd[0], rq->cmd_type, err, stat);

  	if (rq->cmd_type == REQ_TYPE_SENSE) {

  		/*
  		 * We got an error trying to get sense info from the drive
  		 * (probably while trying to recover from a former error).
  		 * Just give up.
  		 */

  		rq->cmd_flags |= REQ_FAILED;

  		return 2;

  	}

  	/* if we have an error, pass CHECK_CONDITION as the SCSI status byte */

  	if (rq->cmd_type == REQ_TYPE_BLOCK_PC && !rq->errors)

  		rq->errors = SAM_STAT_CHECK_CONDITION;

  	if (blk_noretry_request(rq))
  		do_end_request = 1;

  	switch (sense_key) {
  	case NOT_READY:

  		if (rq->cmd_type == REQ_TYPE_FS && rq_data_dir(rq) == WRITE) {

  			if (ide_cd_breathe(drive, rq))
  				return 1;
  		} else {

  			cdrom_saw_media_change(drive);

  			if (rq->cmd_type == REQ_TYPE_FS &&

  			    !(rq->cmd_flags & REQ_QUIET))

  				printk(KERN_ERR PFX "%s: tray open
  ",
  					drive->name);

  		}

  		do_end_request = 1;
  		break;
  	case UNIT_ATTENTION:
  		cdrom_saw_media_change(drive);

  		if (rq->cmd_type != REQ_TYPE_FS)

  			return 0;

  		/*

  		 * Arrange to retry the request but be sure to give up if we've
  		 * retried too many times.

  		 */

  		if (++rq->errors > ERROR_MAX)
  			do_end_request = 1;
  		break;
  	case ILLEGAL_REQUEST:

  		/*

  		 * Don't print error message for this condition -- SFF8090i
  		 * indicates that 5/24/00 is the correct response to a request
  		 * to close the tray if the drive doesn't have that capability.
  		 *
  		 * cdrom_log_sense() knows this!

  		 */

  		if (rq->cmd[0] == GPCMD_START_STOP_UNIT)
  			break;
  		/* fall-through */
  	case DATA_PROTECT:
  		/*
  		 * No point in retrying after an illegal request or data
  		 * protect error.
  		 */

  		if (!(rq->cmd_flags & REQ_QUIET))

  			ide_dump_status(drive, "command error", stat);
  		do_end_request = 1;
  		break;
  	case MEDIUM_ERROR:
  		/*
  		 * No point in re-trying a zillion times on a bad sector.
  		 * If we got here the error is not correctable.
  		 */

  		if (!(rq->cmd_flags & REQ_QUIET))

  			ide_dump_status(drive, "media error "
  					"(bad sector)", stat);
  		do_end_request = 1;
  		break;
  	case BLANK_CHECK:
  		/* disk appears blank? */

  		if (!(rq->cmd_flags & REQ_QUIET))

  			ide_dump_status(drive, "media error (blank)",
  					stat);
  		do_end_request = 1;
  		break;
  	default:

  		if (rq->cmd_type != REQ_TYPE_FS)

  			break;
  		if (err & ~ATA_ABORTED) {
  			/* go to the default handler for other errors */
  			ide_error(drive, "cdrom_decode_status", stat);
  			return 1;
  		} else if (++rq->errors > ERROR_MAX)
  			/* we've racked up too many retries, abort */
  			do_end_request = 1;

  	}

  	if (rq->cmd_type != REQ_TYPE_FS) {

  		rq->cmd_flags |= REQ_FAILED;
  		do_end_request = 1;
  	}
  
  	/*
  	 * End a request through request sense analysis when we have sense data.
  	 * We need this in order to perform end of media processing.
  	 */
  	if (do_end_request)
  		goto end_request;
  
  	/* if we got a CHECK_CONDITION status, queue a request sense command */
  	if (stat & ATA_ERR)

  		return ide_queue_sense_rq(drive, NULL) ? 2 : 1;

  	return 1;

  end_request:

  	if (stat & ATA_ERR) {

  		hwif->rq = NULL;

  		return ide_queue_sense_rq(drive, rq) ? 2 : 1;

  	} else

  		return 2;

  }

  static void ide_cd_request_sense_fixup(ide_drive_t *drive, struct ide_cmd *cmd)

  {

  	struct request *rq = cmd->rq;

  	ide_debug_log(IDE_DBG_FUNC, "rq->cmd[0]: 0x%x", rq->cmd[0]);

  	/*
  	 * Some of the trailing request sense fields are optional,
  	 * and some drives don't send them.  Sigh.
  	 */
  	if (rq->cmd[0] == GPCMD_REQUEST_SENSE &&

  	    cmd->nleft > 0 && cmd->nleft <= 5)
  		cmd->nleft = 0;

  }

  int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,
  		    int write, void *buffer, unsigned *bufflen,
  		    struct request_sense *sense, int timeout,
  		    unsigned int cmd_flags)

  {

  	struct cdrom_info *info = drive->driver_data;
  	struct request_sense local_sense;

  	int retries = 10;

  	unsigned int flags = 0;

  	if (!sense)
  		sense = &local_sense;

  	ide_debug_log(IDE_DBG_PC, "cmd[0]: 0x%x, write: 0x%x, timeout: %d, "
  				  "cmd_flags: 0x%x",
  				  cmd[0], write, timeout, cmd_flags);

  	/* start of retry loop */

  	do {

  		struct request *rq;

  		int error;

  		rq = blk_get_request(drive->queue, write, __GFP_WAIT);
  
  		memcpy(rq->cmd, cmd, BLK_MAX_CDB);
  		rq->cmd_type = REQ_TYPE_ATA_PC;
  		rq->sense = sense;
  		rq->cmd_flags |= cmd_flags;
  		rq->timeout = timeout;
  		if (buffer) {

  			error = blk_rq_map_kern(drive->queue, rq, buffer,
  						*bufflen, GFP_NOIO);
  			if (error) {
  				blk_put_request(rq);
  				return error;
  			}

  		}
  
  		error = blk_execute_rq(drive->queue, info->disk, rq, 0);
  
  		if (buffer)

  			*bufflen = rq->resid_len;

  
  		flags = rq->cmd_flags;
  		blk_put_request(rq);

  		/*
  		 * FIXME: we should probably abort/retry or something in case of
  		 * failure.
  		 */

  		if (flags & REQ_FAILED) {

  			/*
  			 * The request failed.  Retry if it was due to a unit
  			 * attention status (usually means media was changed).
  			 */

  			struct request_sense *reqbuf = sense;

  
  			if (reqbuf->sense_key == UNIT_ATTENTION)
  				cdrom_saw_media_change(drive);
  			else if (reqbuf->sense_key == NOT_READY &&
  				 reqbuf->asc == 4 && reqbuf->ascq != 4) {

  				/*
  				 * The drive is in the process of loading
  				 * a disk.  Retry, but wait a little to give
  				 * the drive time to complete the load.
  				 */

  				ssleep(2);
  			} else {

  				/* otherwise, don't retry */

  				retries = 0;
  			}
  			--retries;
  		}

  		/* end of retry loop */

  	} while ((flags & REQ_FAILED) && retries >= 0);

  	/* return an error if the command failed */

  	return (flags & REQ_FAILED) ? -EIO : 0;

  }

  /*
   * returns true if rq has been completed
   */
  static bool ide_cd_error_cmd(ide_drive_t *drive, struct ide_cmd *cmd)

  {
  	unsigned int nr_bytes = cmd->nbytes - cmd->nleft;
  
  	if (cmd->tf_flags & IDE_TFLAG_WRITE)
  		nr_bytes -= cmd->last_xfer_len;

  	if (nr_bytes > 0) {

  		ide_complete_rq(drive, 0, nr_bytes);

  		return true;
  	}
  
  	return false;

  }

  static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
  {

  	ide_hwif_t *hwif = drive->hwif;

  	struct ide_cmd *cmd = &hwif->cmd;

  	struct request *rq = hwif->rq;

  	ide_expiry_t *expiry = NULL;

  	int dma_error = 0, dma, thislen, uptodate = 0;

  	int write = (rq_data_dir(rq) == WRITE) ? 1 : 0, rc = 0;

  	int sense = (rq->cmd_type == REQ_TYPE_SENSE);

  	unsigned int timeout;

  	u16 len;

  	u8 ireason, stat;

  	ide_debug_log(IDE_DBG_PC, "cmd: 0x%x, write: 0x%x", rq->cmd[0], write);

  	/* check for errors */

  	dma = drive->dma;

  	if (dma) {

  		drive->dma = 0;

  		drive->waiting_for_dma = 0;

  		dma_error = hwif->dma_ops->dma_end(drive);

  		ide_dma_unmap_sg(drive, cmd);

  		if (dma_error) {

  			printk(KERN_ERR PFX "%s: DMA %s error
  ", drive->name,

  					write ? "write" : "read");

  			ide_dma_off(drive);
  		}

  	}

  	/* check status */
  	stat = hwif->tp_ops->read_status(hwif);
  
  	if (!OK_STAT(stat, 0, BAD_R_STAT)) {
  		rc = cdrom_decode_status(drive, stat);
  		if (rc) {
  			if (rc == 2)
  				goto out_end;
  			return ide_stopped;
  		}

  	}

  	/* using dma, transfer is complete now */

  	if (dma) {

  		if (dma_error)

  			return ide_error(drive, "dma error", stat);

  		uptodate = 1;

  		goto out_end;

  	}

  	ide_read_bcount_and_ireason(drive, &len, &ireason);

  	thislen = (rq->cmd_type == REQ_TYPE_FS) ? len : cmd->nleft;

  	if (thislen > len)
  		thislen = len;

  	ide_debug_log(IDE_DBG_PC, "DRQ: stat: 0x%x, thislen: %d",
  				  stat, thislen);

  	/* If DRQ is clear, the command has completed. */

  	if ((stat & ATA_DRQ) == 0) {

  		if (rq->cmd_type == REQ_TYPE_FS) {

  			/*
  			 * If we're not done reading/writing, complain.
  			 * Otherwise, complete the command normally.
  			 */
  			uptodate = 1;

  			if (cmd->nleft > 0) {

  				printk(KERN_ERR PFX "%s: %s: data underrun "

  					"(%u bytes)
  ", drive->name, __func__,
  					cmd->nleft);

  				if (!write)
  					rq->cmd_flags |= REQ_FAILED;
  				uptodate = 0;
  			}

  		} else if (rq->cmd_type != REQ_TYPE_BLOCK_PC) {

  			ide_cd_request_sense_fixup(drive, cmd);

  			uptodate = cmd->nleft ? 0 : 1;

  
  			/*
  			 * suck out the remaining bytes from the drive in an
  			 * attempt to complete the data xfer. (see BZ#13399)
  			 */
  			if (!(stat & ATA_ERR) && !uptodate && thislen) {
  				ide_pio_bytes(drive, cmd, write, thislen);
  				uptodate = cmd->nleft ? 0 : 1;
  			}
  
  			if (!uptodate)

  				rq->cmd_flags |= REQ_FAILED;

  		}

  		goto out_end;

  	}

  	rc = ide_check_ireason(drive, rq, len, ireason, write);

  	if (rc)
  		goto out_end;

  	cmd->last_xfer_len = 0;

  	ide_debug_log(IDE_DBG_PC, "data transfer, rq->cmd_type: 0x%x, "
  				  "ireason: 0x%x",
  				  rq->cmd_type, ireason);

  	/* transfer data */

  	while (thislen > 0) {

  		int blen = min_t(int, thislen, cmd->nleft);

  		if (cmd->nleft == 0)

  			break;

  		ide_pio_bytes(drive, cmd, write, blen);
  		cmd->last_xfer_len += blen;

  
  		thislen -= blen;
  		len -= blen;

  		if (sense && write == 0)

  			rq->sense_len += blen;

  	}

  	/* pad, if necessary */

  	if (len > 0) {

  		if (rq->cmd_type != REQ_TYPE_FS || write == 0)

  			ide_pad_transfer(drive, write, len);
  		else {
  			printk(KERN_ERR PFX "%s: confused, missing data
  ",
  				drive->name);
  			blk_dump_rq_flags(rq, "cdrom_newpc_intr");
  		}
  	}

  	if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {

  		timeout = rq->timeout;

  	} else {
  		timeout = ATAPI_WAIT_PC;

  		if (rq->cmd_type != REQ_TYPE_FS)

  			expiry = ide_cd_expiry;

  	}

  	hwif->expiry = expiry;
  	ide_set_handler(drive, cdrom_newpc_intr, timeout);

  	return ide_started;

  out_end:

  	if (rq->cmd_type == REQ_TYPE_BLOCK_PC && rc == 0) {

  		rq->resid_len = 0;

  		blk_end_request_all(rq, 0);

  		hwif->rq = NULL;

  	} else {

  		if (sense && uptodate)
  			ide_cd_complete_failed_rq(drive, rq);

  		if (rq->cmd_type == REQ_TYPE_FS) {

  			if (cmd->nleft == 0)

  				uptodate = 1;
  		} else {
  			if (uptodate <= 0 && rq->errors == 0)
  				rq->errors = -EIO;
  		}

  		if (uptodate == 0 && rq->bio)

  			if (ide_cd_error_cmd(drive, cmd))
  				return ide_stopped;

  		/* make sure it's fully ended */

  		if (rq->cmd_type != REQ_TYPE_FS) {

  			rq->resid_len -= cmd->nbytes - cmd->nleft;

  			if (uptodate == 0 && (cmd->tf_flags & IDE_TFLAG_WRITE))

  				rq->resid_len += cmd->last_xfer_len;

  		}

  		ide_complete_rq(drive, uptodate ? 0 : -EIO, blk_rq_bytes(rq));

  		if (sense && rc == 2)
  			ide_error(drive, "request sense failure", stat);

  	}
  	return ide_stopped;

  }

  static ide_startstop_t cdrom_start_rw(ide_drive_t *drive, struct request *rq)

  {

  	struct cdrom_info *cd = drive->driver_data;

  	struct request_queue *q = drive->queue;

  	int write = rq_data_dir(rq) == WRITE;
  	unsigned short sectors_per_frame =

  		queue_logical_block_size(q) >> SECTOR_BITS;

  	ide_debug_log(IDE_DBG_RQ, "rq->cmd[0]: 0x%x, rq->cmd_flags: 0x%x, "

  				  "secs_per_frame: %u",

  				  rq->cmd[0], rq->cmd_flags, sectors_per_frame);

  	if (write) {

  		/* disk has become write protected */

  		if (get_disk_ro(cd->disk))

  			return ide_stopped;

  	} else {
  		/*
  		 * We may be retrying this request after an error.  Fix up any
  		 * weirdness which might be present in the request packet.
  		 */

  		q->prep_rq_fn(q, rq);

  	}

  	/* fs requests *must* be hardware frame aligned */

  	if ((blk_rq_sectors(rq) & (sectors_per_frame - 1)) ||
  	    (blk_rq_pos(rq) & (sectors_per_frame - 1)))

  		return ide_stopped;
  
  	/* use DMA, if possible */
  	drive->dma = !!(drive->dev_flags & IDE_DFLAG_USING_DMA);

  	if (write)
  		cd->devinfo.media_written = 1;

  	rq->timeout = ATAPI_WAIT_PC;

  	return ide_started;

  }

  static void cdrom_do_block_pc(ide_drive_t *drive, struct request *rq)

  {

  	ide_debug_log(IDE_DBG_PC, "rq->cmd[0]: 0x%x, rq->cmd_type: 0x%x",
  				  rq->cmd[0], rq->cmd_type);

  	if (rq->cmd_type == REQ_TYPE_BLOCK_PC)

  		rq->cmd_flags |= REQ_QUIET;
  	else
  		rq->cmd_flags &= ~REQ_FAILED;

  	drive->dma = 0;

  	/* sg request */

  	if (rq->bio) {

  		struct request_queue *q = drive->queue;

  		char *buf = bio_data(rq->bio);

  		unsigned int alignment;

  		drive->dma = !!(drive->dev_flags & IDE_DFLAG_USING_DMA);

  
  		/*
  		 * check if dma is safe

  		 *
  		 * NOTE! The "len" and "addr" checks should possibly have
  		 * separate masks.

  		 */

  		alignment = queue_dma_alignment(q) | q->dma_pad_mask;

  		if ((unsigned long)buf & alignment

  		    || blk_rq_bytes(rq) & q->dma_pad_mask

  		    || object_is_on_stack(buf))

  			drive->dma = 0;

  	}

  }

  static ide_startstop_t ide_cd_do_request(ide_drive_t *drive, struct request *rq,

  					sector_t block)

  {

  	struct ide_cmd cmd;

  	int uptodate = 0;
  	unsigned int nsectors;

  	ide_debug_log(IDE_DBG_RQ, "cmd: 0x%x, block: %llu",
  				  rq->cmd[0], (unsigned long long)block);
  
  	if (drive->debug_mask & IDE_DBG_RQ)
  		blk_dump_rq_flags(rq, "ide_cd_do_request");

  	switch (rq->cmd_type) {
  	case REQ_TYPE_FS:

  		if (cdrom_start_rw(drive, rq) == ide_stopped)

  			goto out_end;

  		break;
  	case REQ_TYPE_SENSE:
  	case REQ_TYPE_BLOCK_PC:
  	case REQ_TYPE_ATA_PC:

  		if (!rq->timeout)
  			rq->timeout = ATAPI_WAIT_PC;

  		cdrom_do_block_pc(drive, rq);

  		break;
  	case REQ_TYPE_SPECIAL:

  		/* right now this can only be a reset... */

  		uptodate = 1;
  		goto out_end;

  	default:

  		BUG();

  	}

  	/* 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;

  	if (rq->cmd_type == REQ_TYPE_FS || blk_rq_bytes(rq)) {

  		ide_init_sg_cmd(&cmd, blk_rq_bytes(rq));

  		ide_map_sg(drive, &cmd);
  	}

  	return ide_issue_pc(drive, &cmd);

  out_end:

  	nsectors = blk_rq_sectors(rq);

  
  	if (nsectors == 0)
  		nsectors = 1;
  
  	ide_complete_rq(drive, uptodate ? 0 : -EIO, nsectors << 9);

  	return ide_stopped;

  }

  /*

   * Ioctl handling.
   *

   * Routines which queue packet commands take as a final argument a pointer to a
   * request_sense struct. If execution of the command results in an error with a
   * CHECK CONDITION status, this structure will be filled with the results of the
   * subsequent request sense command. The pointer can also be NULL, in which case
   * no sense information is returned.

   */

  static void msf_from_bcd(struct atapi_msf *msf)

  {

  	msf->minute = bcd2bin(msf->minute);
  	msf->second = bcd2bin(msf->second);
  	msf->frame  = bcd2bin(msf->frame);

  }

  int cdrom_check_status(ide_drive_t *drive, struct request_sense *sense)

  {

  	struct cdrom_info *info = drive->driver_data;
  	struct cdrom_device_info *cdi = &info->devinfo;

  	unsigned char cmd[BLK_MAX_CDB];

  	ide_debug_log(IDE_DBG_FUNC, "enter");

  	memset(cmd, 0, BLK_MAX_CDB);
  	cmd[0] = GPCMD_TEST_UNIT_READY;

  	/*

  	 * Sanyo 3 CD changer uses byte 7 of TEST_UNIT_READY to switch CDs
  	 * instead of supporting the LOAD_UNLOAD opcode.

  	 */

  	cmd[7] = cdi->sanyo_slot % 3;

  	return ide_cd_queue_pc(drive, cmd, 0, NULL, NULL, sense, 0, REQ_QUIET);

  }

  static int cdrom_read_capacity(ide_drive_t *drive, unsigned long *capacity,
  			       unsigned long *sectors_per_frame,
  			       struct request_sense *sense)
  {
  	struct {

  		__be32 lba;
  		__be32 blocklen;

  	} capbuf;
  
  	int stat;

  	unsigned char cmd[BLK_MAX_CDB];
  	unsigned len = sizeof(capbuf);

  	u32 blocklen;

  	ide_debug_log(IDE_DBG_FUNC, "enter");

  	memset(cmd, 0, BLK_MAX_CDB);
  	cmd[0] = GPCMD_READ_CDVD_CAPACITY;

  	stat = ide_cd_queue_pc(drive, cmd, 0, &capbuf, &len, sense, 0,
  			       REQ_QUIET);

  	if (stat)
  		return stat;
  
  	/*

  	 * Sanity check the given block size, in so far as making
  	 * sure the sectors_per_frame we give to the caller won't
  	 * end up being bogus.

  	 */

  	blocklen = be32_to_cpu(capbuf.blocklen);

  	blocklen = (blocklen >> SECTOR_BITS) << SECTOR_BITS;

  	switch (blocklen) {
  	case 512:
  	case 1024:
  	case 2048:
  	case 4096:

  		break;
  	default:

  		printk_once(KERN_ERR PFX "%s: weird block size %u; "
  				"setting default block size to 2048
  ",

  				drive->name, blocklen);

  		blocklen = 2048;

  		break;

  	}

  	*capacity = 1 + be32_to_cpu(capbuf.lba);

  	*sectors_per_frame = blocklen >> SECTOR_BITS;

  	ide_debug_log(IDE_DBG_PROBE, "cap: %lu, sectors_per_frame: %lu",
  				     *capacity, *sectors_per_frame);

  	return 0;

  }
  
  static int cdrom_read_tocentry(ide_drive_t *drive, int trackno, int msf_flag,
  				int format, char *buf, int buflen,
  				struct request_sense *sense)
  {

  	unsigned char cmd[BLK_MAX_CDB];

  	ide_debug_log(IDE_DBG_FUNC, "enter");

  	memset(cmd, 0, BLK_MAX_CDB);

  	cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
  	cmd[6] = trackno;
  	cmd[7] = (buflen >> 8);
  	cmd[8] = (buflen & 0xff);
  	cmd[9] = (format << 6);

  
  	if (msf_flag)

  		cmd[1] = 2;

  	return ide_cd_queue_pc(drive, cmd, 0, buf, &buflen, sense, 0, REQ_QUIET);

  }

  /* Try to read the entire TOC for the disk into our internal buffer. */

  int ide_cd_read_toc(ide_drive_t *drive, struct request_sense *sense)

  {
  	int stat, ntracks, i;
  	struct cdrom_info *info = drive->driver_data;
  	struct cdrom_device_info *cdi = &info->devinfo;
  	struct atapi_toc *toc = info->toc;
  	struct {
  		struct atapi_toc_header hdr;
  		struct atapi_toc_entry  ent;
  	} ms_tmp;
  	long last_written;
  	unsigned long sectors_per_frame = SECTORS_PER_FRAME;

  	ide_debug_log(IDE_DBG_FUNC, "enter");

  	if (toc == NULL) {

  		/* try to allocate space */

  		toc = kmalloc(sizeof(struct atapi_toc), GFP_KERNEL);

  		if (toc == NULL) {

  			printk(KERN_ERR PFX "%s: No cdrom TOC buffer!
  ",

  					drive->name);

  			return -ENOMEM;
  		}

  		info->toc = toc;

  	}

  	/*
  	 * Check to see if the existing data is still valid. If it is,
  	 * just return.
  	 */

  	(void) cdrom_check_status(drive, sense);

  	if (drive->atapi_flags & IDE_AFLAG_TOC_VALID)

  		return 0;

  	/* try to get the total cdrom capacity and sector size */

  	stat = cdrom_read_capacity(drive, &toc->capacity, &sectors_per_frame,
  				   sense);
  	if (stat)
  		toc->capacity = 0x1fffff;
  
  	set_capacity(info->disk, toc->capacity * sectors_per_frame);

  	/* save a private copy of the TOC capacity for error handling */

  	drive->probed_capacity = toc->capacity * sectors_per_frame;

  	blk_queue_logical_block_size(drive->queue,
  				     sectors_per_frame << SECTOR_BITS);

  	/* first read just the header, so we know how long the TOC is */

  	stat = cdrom_read_tocentry(drive, 0, 1, 0, (char *) &toc->hdr,
  				    sizeof(struct atapi_toc_header), sense);

  	if (stat)
  		return stat;

  	if (drive->atapi_flags & IDE_AFLAG_TOCTRACKS_AS_BCD) {

  		toc->hdr.first_track = bcd2bin(toc->hdr.first_track);
  		toc->hdr.last_track  = bcd2bin(toc->hdr.last_track);

  	}

  
  	ntracks = toc->hdr.last_track - toc->hdr.first_track + 1;
  	if (ntracks <= 0)
  		return -EIO;
  	if (ntracks > MAX_TRACKS)
  		ntracks = MAX_TRACKS;

  	/* now read the whole schmeer */

  	stat = cdrom_read_tocentry(drive, toc->hdr.first_track, 1, 0,
  				  (char *)&toc->hdr,
  				   sizeof(struct atapi_toc_header) +
  				   (ntracks + 1) *
  				   sizeof(struct atapi_toc_entry), sense);
  
  	if (stat && toc->hdr.first_track > 1) {

  		/*
  		 * Cds with CDI tracks only don't have any TOC entries, despite
  		 * of this the returned values are
  		 * first_track == last_track = number of CDI tracks + 1,
  		 * so that this case is indistinguishable from the same layout
  		 * plus an additional audio track. If we get an error for the
  		 * regular case, we assume a CDI without additional audio
  		 * tracks. In this case the readable TOC is empty (CDI tracks
  		 * are not included) and only holds the Leadout entry.
  		 *
  		 * Heiko Eißfeldt.
  		 */

  		ntracks = 0;
  		stat = cdrom_read_tocentry(drive, CDROM_LEADOUT, 1, 0,
  					   (char *)&toc->hdr,
  					   sizeof(struct atapi_toc_header) +
  					   (ntracks + 1) *
  					   sizeof(struct atapi_toc_entry),
  					   sense);

  		if (stat)

  			return stat;

  		if (drive->atapi_flags & IDE_AFLAG_TOCTRACKS_AS_BCD) {

  			toc->hdr.first_track = (u8)bin2bcd(CDROM_LEADOUT);
  			toc->hdr.last_track = (u8)bin2bcd(CDROM_LEADOUT);

  		} else {

  			toc->hdr.first_track = CDROM_LEADOUT;
  			toc->hdr.last_track = CDROM_LEADOUT;
  		}
  	}
  
  	if (stat)
  		return stat;

  	toc->hdr.toc_length = be16_to_cpu(toc->hdr.toc_length);

  	if (drive->atapi_flags & IDE_AFLAG_TOCTRACKS_AS_BCD) {

  		toc->hdr.first_track = bcd2bin(toc->hdr.first_track);
  		toc->hdr.last_track  = bcd2bin(toc->hdr.last_track);

  	}

  	for (i = 0; i <= ntracks; i++) {

  		if (drive->atapi_flags & IDE_AFLAG_TOCADDR_AS_BCD) {
  			if (drive->atapi_flags & IDE_AFLAG_TOCTRACKS_AS_BCD)

  				toc->ent[i].track = bcd2bin(toc->ent[i].track);

  			msf_from_bcd(&toc->ent[i].addr.msf);
  		}

  		toc->ent[i].addr.lba = msf_to_lba(toc->ent[i].addr.msf.minute,
  						  toc->ent[i].addr.msf.second,
  						  toc->ent[i].addr.msf.frame);

  	}

  	if (toc->hdr.first_track != CDROM_LEADOUT) {

  		/* read the multisession information */

  		stat = cdrom_read_tocentry(drive, 0, 0, 1, (char *)&ms_tmp,
  					   sizeof(ms_tmp), sense);

  		if (stat)
  			return stat;

  
  		toc->last_session_lba = be32_to_cpu(ms_tmp.ent.addr.lba);
  	} else {

  		ms_tmp.hdr.last_track = CDROM_LEADOUT;
  		ms_tmp.hdr.first_track = ms_tmp.hdr.last_track;

  		toc->last_session_lba = msf_to_lba(0, 2, 0); /* 0m 2s 0f */
  	}

  	if (drive->atapi_flags & IDE_AFLAG_TOCADDR_AS_BCD) {

  		/* re-read multisession information using MSF format */

  		stat = cdrom_read_tocentry(drive, 0, 1, 1, (char *)&ms_tmp,
  					   sizeof(ms_tmp), sense);
  		if (stat)
  			return stat;

  		msf_from_bcd(&ms_tmp.ent.addr.msf);

  		toc->last_session_lba = msf_to_lba(ms_tmp.ent.addr.msf.minute,

  						   ms_tmp.ent.addr.msf.second,

  						   ms_tmp.ent.addr.msf.frame);
  	}

  
  	toc->xa_flag = (ms_tmp.hdr.first_track != ms_tmp.hdr.last_track);

  	/* now try to get the total cdrom capacity */

  	stat = cdrom_get_last_written(cdi, &last_written);
  	if (!stat && (last_written > toc->capacity)) {
  		toc->capacity = last_written;
  		set_capacity(info->disk, toc->capacity * sectors_per_frame);

  		drive->probed_capacity = toc->capacity * sectors_per_frame;

  	}
  
  	/* Remember that we've read this stuff. */

  	drive->atapi_flags |= IDE_AFLAG_TOC_VALID;

  
  	return 0;
  }

  int ide_cdrom_get_capabilities(ide_drive_t *drive, u8 *buf)

  {
  	struct cdrom_info *info = drive->driver_data;
  	struct cdrom_device_info *cdi = &info->devinfo;
  	struct packet_command cgc;

  	int stat, attempts = 3, size = ATAPI_CAPABILITIES_PAGE_SIZE;

  	ide_debug_log(IDE_DBG_FUNC, "enter");

  	if ((drive->atapi_flags & IDE_AFLAG_FULL_CAPS_PAGE) == 0)

  		size -= ATAPI_CAPABILITIES_PAGE_PAD_SIZE;

  	init_cdrom_command(&cgc, buf, size, CGC_DATA_UNKNOWN);

  	do {
  		/* we seem to get stat=0x01,err=0x00 the first time (??) */

  		stat = cdrom_mode_sense(cdi, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
  		if (!stat)
  			break;
  	} while (--attempts);
  	return stat;
  }

  void ide_cdrom_update_speed(ide_drive_t *drive, u8 *buf)

  {

  	struct cdrom_info *cd = drive->driver_data;

  	u16 curspeed, maxspeed;

  	ide_debug_log(IDE_DBG_FUNC, "enter");

  	if (drive->atapi_flags & IDE_AFLAG_LE_SPEED_FIELDS) {

  		curspeed = le16_to_cpup((__le16 *)&buf[8 + 14]);
  		maxspeed = le16_to_cpup((__le16 *)&buf[8 + 8]);

  	} else {

  		curspeed = be16_to_cpup((__be16 *)&buf[8 + 14]);
  		maxspeed = be16_to_cpup((__be16 *)&buf[8 + 8]);

  	}

  	ide_debug_log(IDE_DBG_PROBE, "curspeed: %u, maxspeed: %u",
  				     curspeed, maxspeed);

  	cd->current_speed = DIV_ROUND_CLOSEST(curspeed, 176);
  	cd->max_speed = DIV_ROUND_CLOSEST(maxspeed, 176);

  }

  #define IDE_CD_CAPABILITIES \
  	(CDC_CLOSE_TRAY | CDC_OPEN_TRAY | CDC_LOCK | CDC_SELECT_SPEED | \
  	 CDC_SELECT_DISC | CDC_MULTI_SESSION | CDC_MCN | CDC_MEDIA_CHANGED | \
  	 CDC_PLAY_AUDIO | CDC_RESET | CDC_DRIVE_STATUS | CDC_CD_R | \
  	 CDC_CD_RW | CDC_DVD | CDC_DVD_R | CDC_DVD_RAM | CDC_GENERIC_PACKET | \
  	 CDC_MO_DRIVE | CDC_MRW | CDC_MRW_W | CDC_RAM)

  static struct cdrom_device_ops ide_cdrom_dops = {
  	.open			= ide_cdrom_open_real,
  	.release		= ide_cdrom_release_real,
  	.drive_status		= ide_cdrom_drive_status,

  	.check_events		= ide_cdrom_check_events_real,

  	.tray_move		= ide_cdrom_tray_move,
  	.lock_door		= ide_cdrom_lock_door,
  	.select_speed		= ide_cdrom_select_speed,
  	.get_last_session	= ide_cdrom_get_last_session,
  	.get_mcn		= ide_cdrom_get_mcn,
  	.reset			= ide_cdrom_reset,
  	.audio_ioctl		= ide_cdrom_audio_ioctl,

  	.capability		= IDE_CD_CAPABILITIES,

  	.generic_packet		= ide_cdrom_packet,
  };

  static int ide_cdrom_register(ide_drive_t *drive, int nslots)

  {
  	struct cdrom_info *info = drive->driver_data;
  	struct cdrom_device_info *devinfo = &info->devinfo;

  	ide_debug_log(IDE_DBG_PROBE, "nslots: %d", nslots);

  	devinfo->ops = &ide_cdrom_dops;

  	devinfo->speed = info->current_speed;

  	devinfo->capacity = nslots;

  	devinfo->handle = drive;

  	strcpy(devinfo->name, drive->name);

  	if (drive->atapi_flags & IDE_AFLAG_NO_SPEED_SELECT)

  		devinfo->mask |= CDC_SELECT_SPEED;

  	devinfo->disk = info->disk;
  	return register_cdrom(devinfo);
  }

  static int ide_cdrom_probe_capabilities(ide_drive_t *drive)

  {

  	struct cdrom_info *cd = drive->driver_data;
  	struct cdrom_device_info *cdi = &cd->devinfo;

  	u8 buf[ATAPI_CAPABILITIES_PAGE_SIZE];
  	mechtype_t mechtype;

  	int nslots = 1;

  	ide_debug_log(IDE_DBG_PROBE, "media: 0x%x, atapi_flags: 0x%lx",
  				     drive->media, drive->atapi_flags);

  	cdi->mask = (CDC_CD_R | CDC_CD_RW | CDC_DVD | CDC_DVD_R |
  		     CDC_DVD_RAM | CDC_SELECT_DISC | CDC_PLAY_AUDIO |
  		     CDC_MO_DRIVE | CDC_RAM);

  	if (drive->media == ide_optical) {

  		cdi->mask &= ~(CDC_MO_DRIVE | CDC_RAM);

  		printk(KERN_ERR PFX "%s: ATAPI magneto-optical drive
  ",

  				drive->name);

  		return nslots;
  	}

  	if (drive->atapi_flags & IDE_AFLAG_PRE_ATAPI12) {
  		drive->atapi_flags &= ~IDE_AFLAG_NO_EJECT;

  		cdi->mask &= ~CDC_PLAY_AUDIO;

  		return nslots;
  	}
  
  	/*

  	 * We have to cheat a little here. the packet will eventually be queued
  	 * with ide_cdrom_packet(), which extracts the drive from cdi->handle.
  	 * Since this device hasn't been registered with the Uniform layer yet,
  	 * it can't do this. Same goes for cdi->ops.

  	 */

  	cdi->handle = drive;

  	cdi->ops = &ide_cdrom_dops;

  	if (ide_cdrom_get_capabilities(drive, buf))