Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1058 insertions, 0 deletions

diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
new file mode 100644
index 000000000..fdbd5c691
--- /dev/null
+++ b/drivers/scsi/sr.c
@@ -0,0 +1,1058 @@
+/*
+ *  sr.c Copyright (C) 1992 David Giller
+ *           Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
+ *
+ *  adapted from:
+ *      sd.c Copyright (C) 1992 Drew Eckhardt
+ *      Linux scsi disk driver by
+ *              Drew Eckhardt <drew@colorado.edu>
+ *
+ *	Modified by Eric Youngdale ericy@andante.org to
+ *	add scatter-gather, multiple outstanding request, and other
+ *	enhancements.
+ *
+ *      Modified by Eric Youngdale eric@andante.org to support loadable
+ *      low-level scsi drivers.
+ *
+ *      Modified by Thomas Quinot thomas@melchior.cuivre.fdn.fr to
+ *      provide auto-eject.
+ *
+ *      Modified by Gerd Knorr <kraxel@cs.tu-berlin.de> to support the
+ *      generic cdrom interface
+ *
+ *      Modified by Jens Axboe <axboe@suse.de> - Uniform sr_packet()
+ *      interface, capabilities probe additions, ioctl cleanups, etc.
+ *
+ *	Modified by Richard Gooch <rgooch@atnf.csiro.au> to support devfs
+ *
+ *	Modified by Jens Axboe <axboe@suse.de> - support DVD-RAM
+ *	transparently and lose the GHOST hack
+ *
+ *	Modified by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *	check resource allocation in sr_init and some cleanups
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/bio.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/cdrom.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/uaccess.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_driver.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_ioctl.h>	/* For the door lock/unlock commands */
+
+#include "scsi_logging.h"
+#include "sr.h"
+
+
+MODULE_DESCRIPTION("SCSI cdrom (sr) driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_CDROM_MAJOR);
+MODULE_ALIAS_SCSI_DEVICE(TYPE_ROM);
+MODULE_ALIAS_SCSI_DEVICE(TYPE_WORM);
+
+#define SR_DISKS	256
+
+#define SR_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_MRW|CDC_MRW_W|CDC_RAM)
+
+static DEFINE_MUTEX(sr_mutex);
+static int sr_probe(struct device *);
+static int sr_remove(struct device *);
+static int sr_init_command(struct scsi_cmnd *SCpnt);
+static int sr_done(struct scsi_cmnd *);
+static int sr_runtime_suspend(struct device *dev);
+
+static const struct dev_pm_ops sr_pm_ops = {
+	.runtime_suspend	= sr_runtime_suspend,
+};
+
+static struct scsi_driver sr_template = {
+	.gendrv = {
+		.name   	= "sr",
+		.owner		= THIS_MODULE,
+		.probe		= sr_probe,
+		.remove		= sr_remove,
+		.pm		= &sr_pm_ops,
+	},
+	.init_command		= sr_init_command,
+	.done			= sr_done,
+};
+
+static unsigned long sr_index_bits[SR_DISKS / BITS_PER_LONG];
+static DEFINE_SPINLOCK(sr_index_lock);
+
+/* This semaphore is used to mediate the 0->1 reference get in the
+ * face of object destruction (i.e. we can't allow a get on an
+ * object after last put) */
+static DEFINE_MUTEX(sr_ref_mutex);
+
+static int sr_open(struct cdrom_device_info *, int);
+static void sr_release(struct cdrom_device_info *);
+
+static void get_sectorsize(struct scsi_cd *);
+static void get_capabilities(struct scsi_cd *);
+
+static unsigned int sr_check_events(struct cdrom_device_info *cdi,
+				    unsigned int clearing, int slot);
+static int sr_packet(struct cdrom_device_info *, struct packet_command *);
+
+static const struct cdrom_device_ops sr_dops = {
+	.open			= sr_open,
+	.release	 	= sr_release,
+	.drive_status	 	= sr_drive_status,
+	.check_events		= sr_check_events,
+	.tray_move		= sr_tray_move,
+	.lock_door		= sr_lock_door,
+	.select_speed		= sr_select_speed,
+	.get_last_session	= sr_get_last_session,
+	.get_mcn		= sr_get_mcn,
+	.reset			= sr_reset,
+	.audio_ioctl		= sr_audio_ioctl,
+	.capability		= SR_CAPABILITIES,
+	.generic_packet		= sr_packet,
+};
+
+static void sr_kref_release(struct kref *kref);
+
+static inline struct scsi_cd *scsi_cd(struct gendisk *disk)
+{
+	return container_of(disk->private_data, struct scsi_cd, driver);
+}
+
+static int sr_runtime_suspend(struct device *dev)
+{
+	struct scsi_cd *cd = dev_get_drvdata(dev);
+
+	if (!cd)	/* E.g.: runtime suspend following sr_remove() */
+		return 0;
+
+	if (cd->media_present)
+		return -EBUSY;
+	else
+		return 0;
+}
+
+/*
+ * The get and put routines for the struct scsi_cd.  Note this entity
+ * has a scsi_device pointer and owns a reference to this.
+ */
+static inline struct scsi_cd *scsi_cd_get(struct gendisk *disk)
+{
+	struct scsi_cd *cd = NULL;
+
+	mutex_lock(&sr_ref_mutex);
+	if (disk->private_data == NULL)
+		goto out;
+	cd = scsi_cd(disk);
+	kref_get(&cd->kref);
+	if (scsi_device_get(cd->device)) {
+		kref_put(&cd->kref, sr_kref_release);
+		cd = NULL;
+	}
+ out:
+	mutex_unlock(&sr_ref_mutex);
+	return cd;
+}
+
+static void scsi_cd_put(struct scsi_cd *cd)
+{
+	struct scsi_device *sdev = cd->device;
+
+	mutex_lock(&sr_ref_mutex);
+	kref_put(&cd->kref, sr_kref_release);
+	scsi_device_put(sdev);
+	mutex_unlock(&sr_ref_mutex);
+}
+
+static unsigned int sr_get_events(struct scsi_device *sdev)
+{
+	u8 buf[8];
+	u8 cmd[] = { GET_EVENT_STATUS_NOTIFICATION,
+		     1,			/* polled */
+		     0, 0,		/* reserved */
+		     1 << 4,		/* notification class: media */
+		     0, 0,		/* reserved */
+		     0, sizeof(buf),	/* allocation length */
+		     0,			/* control */
+	};
+	struct event_header *eh = (void *)buf;
+	struct media_event_desc *med = (void *)(buf + 4);
+	struct scsi_sense_hdr sshdr;
+	int result;
+
+	result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, sizeof(buf),
+				  &sshdr, SR_TIMEOUT, MAX_RETRIES, NULL);
+	if (scsi_sense_valid(&sshdr) && sshdr.sense_key == UNIT_ATTENTION)
+		return DISK_EVENT_MEDIA_CHANGE;
+
+	if (result || be16_to_cpu(eh->data_len) < sizeof(*med))
+		return 0;
+
+	if (eh->nea || eh->notification_class != 0x4)
+		return 0;
+
+	if (med->media_event_code == 1)
+		return DISK_EVENT_EJECT_REQUEST;
+	else if (med->media_event_code == 2)
+		return DISK_EVENT_MEDIA_CHANGE;
+	else if (med->media_event_code == 3)
+		return DISK_EVENT_MEDIA_CHANGE;
+	return 0;
+}
+
+/*
+ * This function checks to see if the media has been changed or eject
+ * button has been pressed.  It is possible that we have already
+ * sensed a change, or the drive may have sensed one and not yet
+ * reported it.  The past events are accumulated in sdev->changed and
+ * returned together with the current state.
+ */
+static unsigned int sr_check_events(struct cdrom_device_info *cdi,
+				    unsigned int clearing, int slot)
+{
+	struct scsi_cd *cd = cdi->handle;
+	bool last_present;
+	struct scsi_sense_hdr sshdr;
+	unsigned int events;
+	int ret;
+
+	/* no changer support */
+	if (CDSL_CURRENT != slot)
+		return 0;
+
+	events = sr_get_events(cd->device);
+	cd->get_event_changed |= events & DISK_EVENT_MEDIA_CHANGE;
+
+	/*
+	 * If earlier GET_EVENT_STATUS_NOTIFICATION and TUR did not agree
+	 * for several times in a row.  We rely on TUR only for this likely
+	 * broken device, to prevent generating incorrect media changed
+	 * events for every open().
+	 */
+	if (cd->ignore_get_event) {
+		events &= ~DISK_EVENT_MEDIA_CHANGE;
+		goto do_tur;
+	}
+
+	/*
+	 * GET_EVENT_STATUS_NOTIFICATION is enough unless MEDIA_CHANGE
+	 * is being cleared.  Note that there are devices which hang
+	 * if asked to execute TUR repeatedly.
+	 */
+	if (cd->device->changed) {
+		events |= DISK_EVENT_MEDIA_CHANGE;
+		cd->device->changed = 0;
+		cd->tur_changed = true;
+	}
+
+	if (!(clearing & DISK_EVENT_MEDIA_CHANGE))
+		return events;
+do_tur:
+	/* let's see whether the media is there with TUR */
+	last_present = cd->media_present;
+	ret = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
+
+	/*
+	 * Media is considered to be present if TUR succeeds or fails with
+	 * sense data indicating something other than media-not-present
+	 * (ASC 0x3a).
+	 */
+	cd->media_present = scsi_status_is_good(ret) ||
+		(scsi_sense_valid(&sshdr) && sshdr.asc != 0x3a);
+
+	if (last_present != cd->media_present)
+		cd->device->changed = 1;
+
+	if (cd->device->changed) {
+		events |= DISK_EVENT_MEDIA_CHANGE;
+		cd->device->changed = 0;
+		cd->tur_changed = true;
+	}
+
+	if (cd->ignore_get_event)
+		return events;
+
+	/* check whether GET_EVENT is reporting spurious MEDIA_CHANGE */
+	if (!cd->tur_changed) {
+		if (cd->get_event_changed) {
+			if (cd->tur_mismatch++ > 8) {
+				sr_printk(KERN_WARNING, cd,
+					  "GET_EVENT and TUR disagree continuously, suppress GET_EVENT events\n");
+				cd->ignore_get_event = true;
+			}
+		} else {
+			cd->tur_mismatch = 0;
+		}
+	}
+	cd->tur_changed = false;
+	cd->get_event_changed = false;
+
+	return events;
+}
+
+/*
+ * sr_done is the interrupt routine for the device driver.
+ *
+ * It will be notified on the end of a SCSI read / write, and will take one
+ * of several actions based on success or failure.
+ */
+static int sr_done(struct scsi_cmnd *SCpnt)
+{
+	int result = SCpnt->result;
+	int this_count = scsi_bufflen(SCpnt);
+	int good_bytes = (result == 0 ? this_count : 0);
+	int block_sectors = 0;
+	long error_sector;
+	struct scsi_cd *cd = scsi_cd(SCpnt->request->rq_disk);
+
+#ifdef DEBUG
+	scmd_printk(KERN_INFO, SCpnt, "done: %x\n", result);
+#endif
+
+	/*
+	 * Handle MEDIUM ERRORs or VOLUME OVERFLOWs that indicate partial
+	 * success.  Since this is a relatively rare error condition, no
+	 * care is taken to avoid unnecessary additional work such as
+	 * memcpy's that could be avoided.
+	 */
+	if (driver_byte(result) != 0 &&		/* An error occurred */
+	    (SCpnt->sense_buffer[0] & 0x7f) == 0x70) { /* Sense current */
+		switch (SCpnt->sense_buffer[2]) {
+		case MEDIUM_ERROR:
+		case VOLUME_OVERFLOW:
+		case ILLEGAL_REQUEST:
+			if (!(SCpnt->sense_buffer[0] & 0x90))
+				break;
+			error_sector = (SCpnt->sense_buffer[3] << 24) |
+				(SCpnt->sense_buffer[4] << 16) |
+				(SCpnt->sense_buffer[5] << 8) |
+				SCpnt->sense_buffer[6];
+			if (SCpnt->request->bio != NULL)
+				block_sectors =
+					bio_sectors(SCpnt->request->bio);
+			if (block_sectors < 4)
+				block_sectors = 4;
+			if (cd->device->sector_size == 2048)
+				error_sector <<= 2;
+			error_sector &= ~(block_sectors - 1);
+			good_bytes = (error_sector -
+				      blk_rq_pos(SCpnt->request)) << 9;
+			if (good_bytes < 0 || good_bytes >= this_count)
+				good_bytes = 0;
+			/*
+			 * 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 (error_sector < get_capacity(cd->disk) &&
+			    cd->capacity - error_sector < 4 * 75)
+				set_capacity(cd->disk, error_sector);
+			break;
+
+		case RECOVERED_ERROR:
+			good_bytes = this_count;
+			break;
+
+		default:
+			break;
+		}
+	}
+
+	return good_bytes;
+}
+
+static int sr_init_command(struct scsi_cmnd *SCpnt)
+{
+	int block = 0, this_count, s_size;
+	struct scsi_cd *cd;
+	struct request *rq = SCpnt->request;
+	int ret;
+
+	ret = scsi_init_io(SCpnt);
+	if (ret != BLKPREP_OK)
+		goto out;
+	WARN_ON_ONCE(SCpnt != rq->special);
+	cd = scsi_cd(rq->rq_disk);
+
+	/* from here on until we're complete, any goto out
+	 * is used for a killable error condition */
+	ret = BLKPREP_KILL;
+
+	SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
+		"Doing sr request, block = %d\n", block));
+
+	if (!cd->device || !scsi_device_online(cd->device)) {
+		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
+			"Finishing %u sectors\n", blk_rq_sectors(rq)));
+		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
+			"Retry with 0x%p\n", SCpnt));
+		goto out;
+	}
+
+	if (cd->device->changed) {
+		/*
+		 * quietly refuse to do anything to a changed disc until the
+		 * changed bit has been reset
+		 */
+		goto out;
+	}
+
+	/*
+	 * we do lazy blocksize switching (when reading XA sectors,
+	 * see CDROMREADMODE2 ioctl) 
+	 */
+	s_size = cd->device->sector_size;
+	if (s_size > 2048) {
+		if (!in_interrupt())
+			sr_set_blocklength(cd, 2048);
+		else
+			scmd_printk(KERN_INFO, SCpnt,
+				    "can't switch blocksize: in interrupt\n");
+	}
+
+	if (s_size != 512 && s_size != 1024 && s_size != 2048) {
+		scmd_printk(KERN_ERR, SCpnt, "bad sector size %d\n", s_size);
+		goto out;
+	}
+
+	switch (req_op(rq)) {
+	case REQ_OP_WRITE:
+		if (!cd->writeable)
+			goto out;
+		SCpnt->cmnd[0] = WRITE_10;
+		cd->cdi.media_written = 1;
+		break;
+	case REQ_OP_READ:
+		SCpnt->cmnd[0] = READ_10;
+		break;
+	default:
+		blk_dump_rq_flags(rq, "Unknown sr command");
+		goto out;
+	}
+
+	{
+		struct scatterlist *sg;
+		int i, size = 0, sg_count = scsi_sg_count(SCpnt);
+
+		scsi_for_each_sg(SCpnt, sg, sg_count, i)
+			size += sg->length;
+
+		if (size != scsi_bufflen(SCpnt)) {
+			scmd_printk(KERN_ERR, SCpnt,
+				"mismatch count %d, bytes %d\n",
+				size, scsi_bufflen(SCpnt));
+			if (scsi_bufflen(SCpnt) > size)
+				SCpnt->sdb.length = size;
+		}
+	}
+
+	/*
+	 * request doesn't start on hw block boundary, add scatter pads
+	 */
+	if (((unsigned int)blk_rq_pos(rq) % (s_size >> 9)) ||
+	    (scsi_bufflen(SCpnt) % s_size)) {
+		scmd_printk(KERN_NOTICE, SCpnt, "unaligned transfer\n");
+		goto out;
+	}
+
+	this_count = (scsi_bufflen(SCpnt) >> 9) / (s_size >> 9);
+
+
+	SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
+					"%s %d/%u 512 byte blocks.\n",
+					(rq_data_dir(rq) == WRITE) ?
+					"writing" : "reading",
+					this_count, blk_rq_sectors(rq)));
+
+	SCpnt->cmnd[1] = 0;
+	block = (unsigned int)blk_rq_pos(rq) / (s_size >> 9);
+
+	if (this_count > 0xffff) {
+		this_count = 0xffff;
+		SCpnt->sdb.length = this_count * s_size;
+	}
+
+	SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
+	SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
+	SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
+	SCpnt->cmnd[5] = (unsigned char) block & 0xff;
+	SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
+	SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
+	SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
+
+	/*
+	 * We shouldn't disconnect in the middle of a sector, so with a dumb
+	 * host adapter, it's safe to assume that we can at least transfer
+	 * this many bytes between each connect / disconnect.
+	 */
+	SCpnt->transfersize = cd->device->sector_size;
+	SCpnt->underflow = this_count << 9;
+	SCpnt->allowed = MAX_RETRIES;
+
+	/*
+	 * This indicates that the command is ready from our end to be
+	 * queued.
+	 */
+	ret = BLKPREP_OK;
+ out:
+	return ret;
+}
+
+static int sr_block_open(struct block_device *bdev, fmode_t mode)
+{
+	struct scsi_cd *cd;
+	struct scsi_device *sdev;
+	int ret = -ENXIO;
+
+	cd = scsi_cd_get(bdev->bd_disk);
+	if (!cd)
+		goto out;
+
+	sdev = cd->device;
+	scsi_autopm_get_device(sdev);
+	check_disk_change(bdev);
+
+	mutex_lock(&sr_mutex);
+	ret = cdrom_open(&cd->cdi, bdev, mode);
+	mutex_unlock(&sr_mutex);
+
+	scsi_autopm_put_device(sdev);
+	if (ret)
+		scsi_cd_put(cd);
+
+out:
+	return ret;
+}
+
+static void sr_block_release(struct gendisk *disk, fmode_t mode)
+{
+	struct scsi_cd *cd = scsi_cd(disk);
+	mutex_lock(&sr_mutex);
+	cdrom_release(&cd->cdi, mode);
+	scsi_cd_put(cd);
+	mutex_unlock(&sr_mutex);
+}
+
+static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
+			  unsigned long arg)
+{
+	struct scsi_cd *cd = scsi_cd(bdev->bd_disk);
+	struct scsi_device *sdev = cd->device;
+	void __user *argp = (void __user *)arg;
+	int ret;
+
+	mutex_lock(&sr_mutex);
+
+	ret = scsi_ioctl_block_when_processing_errors(sdev, cmd,
+			(mode & FMODE_NDELAY) != 0);
+	if (ret)
+		goto out;
+
+	scsi_autopm_get_device(sdev);
+
+	/*
+	 * Send SCSI addressing ioctls directly to mid level, send other
+	 * ioctls to cdrom/block level.
+	 */
+	switch (cmd) {
+	case SCSI_IOCTL_GET_IDLUN:
+	case SCSI_IOCTL_GET_BUS_NUMBER:
+		ret = scsi_ioctl(sdev, cmd, argp);
+		goto put;
+	}
+
+	ret = cdrom_ioctl(&cd->cdi, bdev, mode, cmd, arg);
+	if (ret != -ENOSYS)
+		goto put;
+
+	ret = scsi_ioctl(sdev, cmd, argp);
+
+put:
+	scsi_autopm_put_device(sdev);
+
+out:
+	mutex_unlock(&sr_mutex);
+	return ret;
+}
+
+static unsigned int sr_block_check_events(struct gendisk *disk,
+					  unsigned int clearing)
+{
+	unsigned int ret = 0;
+	struct scsi_cd *cd;
+
+	cd = scsi_cd_get(disk);
+	if (!cd)
+		return 0;
+
+	if (!atomic_read(&cd->device->disk_events_disable_depth))
+		ret = cdrom_check_events(&cd->cdi, clearing);
+
+	scsi_cd_put(cd);
+	return ret;
+}
+
+static int sr_block_revalidate_disk(struct gendisk *disk)
+{
+	struct scsi_sense_hdr sshdr;
+	struct scsi_cd *cd;
+
+	cd = scsi_cd_get(disk);
+	if (!cd)
+		return -ENXIO;
+
+	/* if the unit is not ready, nothing more to do */
+	if (scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr))
+		goto out;
+
+	sr_cd_check(&cd->cdi);
+	get_sectorsize(cd);
+out:
+	scsi_cd_put(cd);
+	return 0;
+}
+
+static const struct block_device_operations sr_bdops =
+{
+	.owner		= THIS_MODULE,
+	.open		= sr_block_open,
+	.release	= sr_block_release,
+	.ioctl		= sr_block_ioctl,
+	.check_events	= sr_block_check_events,
+	.revalidate_disk = sr_block_revalidate_disk,
+	/* 
+	 * No compat_ioctl for now because sr_block_ioctl never
+	 * seems to pass arbitrary ioctls down to host drivers.
+	 */
+};
+
+static int sr_open(struct cdrom_device_info *cdi, int purpose)
+{
+	struct scsi_cd *cd = cdi->handle;
+	struct scsi_device *sdev = cd->device;
+	int retval;
+
+	/*
+	 * If the device is in error recovery, wait until it is done.
+	 * If the device is offline, then disallow any access to it.
+	 */
+	retval = -ENXIO;
+	if (!scsi_block_when_processing_errors(sdev))
+		goto error_out;
+
+	return 0;
+
+error_out:
+	return retval;	
+}
+
+static void sr_release(struct cdrom_device_info *cdi)
+{
+	struct scsi_cd *cd = cdi->handle;
+
+	if (cd->device->sector_size > 2048)
+		sr_set_blocklength(cd, 2048);
+
+}
+
+static int sr_probe(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct gendisk *disk;
+	struct scsi_cd *cd;
+	int minor, error;
+
+	scsi_autopm_get_device(sdev);
+	error = -ENODEV;
+	if (sdev->type != TYPE_ROM && sdev->type != TYPE_WORM)
+		goto fail;
+
+	error = -ENOMEM;
+	cd = kzalloc(sizeof(*cd), GFP_KERNEL);
+	if (!cd)
+		goto fail;
+
+	kref_init(&cd->kref);
+
+	disk = alloc_disk(1);
+	if (!disk)
+		goto fail_free;
+
+	spin_lock(&sr_index_lock);
+	minor = find_first_zero_bit(sr_index_bits, SR_DISKS);
+	if (minor == SR_DISKS) {
+		spin_unlock(&sr_index_lock);
+		error = -EBUSY;
+		goto fail_put;
+	}
+	__set_bit(minor, sr_index_bits);
+	spin_unlock(&sr_index_lock);
+
+	disk->major = SCSI_CDROM_MAJOR;
+	disk->first_minor = minor;
+	sprintf(disk->disk_name, "sr%d", minor);
+	disk->fops = &sr_bdops;
+	disk->flags = GENHD_FL_CD | GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE;
+	disk->events = DISK_EVENT_MEDIA_CHANGE | DISK_EVENT_EJECT_REQUEST;
+
+	blk_queue_rq_timeout(sdev->request_queue, SR_TIMEOUT);
+
+	cd->device = sdev;
+	cd->disk = disk;
+	cd->driver = &sr_template;
+	cd->disk = disk;
+	cd->capacity = 0x1fffff;
+	cd->device->changed = 1;	/* force recheck CD type */
+	cd->media_present = 1;
+	cd->use = 1;
+	cd->readcd_known = 0;
+	cd->readcd_cdda = 0;
+
+	cd->cdi.ops = &sr_dops;
+	cd->cdi.handle = cd;
+	cd->cdi.mask = 0;
+	cd->cdi.capacity = 1;
+	sprintf(cd->cdi.name, "sr%d", minor);
+
+	sdev->sector_size = 2048;	/* A guess, just in case */
+
+	/* FIXME: need to handle a get_capabilities failure properly ?? */
+	get_capabilities(cd);
+	sr_vendor_init(cd);
+
+	set_capacity(disk, cd->capacity);
+	disk->private_data = &cd->driver;
+	disk->queue = sdev->request_queue;
+	cd->cdi.disk = disk;
+
+	if (register_cdrom(&cd->cdi))
+		goto fail_minor;
+
+	/*
+	 * Initialize block layer runtime PM stuffs before the
+	 * periodic event checking request gets started in add_disk.
+	 */
+	blk_pm_runtime_init(sdev->request_queue, dev);
+
+	dev_set_drvdata(dev, cd);
+	disk->flags |= GENHD_FL_REMOVABLE;
+	device_add_disk(&sdev->sdev_gendev, disk, NULL);
+
+	sdev_printk(KERN_DEBUG, sdev,
+		    "Attached scsi CD-ROM %s\n", cd->cdi.name);
+	scsi_autopm_put_device(cd->device);
+
+	return 0;
+
+fail_minor:
+	spin_lock(&sr_index_lock);
+	clear_bit(minor, sr_index_bits);
+	spin_unlock(&sr_index_lock);
+fail_put:
+	put_disk(disk);
+fail_free:
+	kfree(cd);
+fail:
+	scsi_autopm_put_device(sdev);
+	return error;
+}
+
+
+static void get_sectorsize(struct scsi_cd *cd)
+{
+	unsigned char cmd[10];
+	unsigned char buffer[8];
+	int the_result, retries = 3;
+	int sector_size;
+	struct request_queue *queue;
+
+	do {
+		cmd[0] = READ_CAPACITY;
+		memset((void *) &cmd[1], 0, 9);
+		memset(buffer, 0, sizeof(buffer));
+
+		/* Do the command and wait.. */
+		the_result = scsi_execute_req(cd->device, cmd, DMA_FROM_DEVICE,
+					      buffer, sizeof(buffer), NULL,
+					      SR_TIMEOUT, MAX_RETRIES, NULL);
+
+		retries--;
+
+	} while (the_result && retries);
+
+
+	if (the_result) {
+		cd->capacity = 0x1fffff;
+		sector_size = 2048;	/* A guess, just in case */
+	} else {
+		long last_written;
+
+		cd->capacity = 1 + ((buffer[0] << 24) | (buffer[1] << 16) |
+				    (buffer[2] << 8) | buffer[3]);
+		/*
+		 * READ_CAPACITY doesn't return the correct size on
+		 * certain UDF media.  If last_written is larger, use
+		 * it instead.
+		 *
+		 * http://bugzilla.kernel.org/show_bug.cgi?id=9668
+		 */
+		if (!cdrom_get_last_written(&cd->cdi, &last_written))
+			cd->capacity = max_t(long, cd->capacity, last_written);
+
+		sector_size = (buffer[4] << 24) |
+		    (buffer[5] << 16) | (buffer[6] << 8) | buffer[7];
+		switch (sector_size) {
+			/*
+			 * HP 4020i CD-Recorder reports 2340 byte sectors
+			 * Philips CD-Writers report 2352 byte sectors
+			 *
+			 * Use 2k sectors for them..
+			 */
+		case 0:
+		case 2340:
+		case 2352:
+			sector_size = 2048;
+			/* fall through */
+		case 2048:
+			cd->capacity *= 4;
+			/* fall through */
+		case 512:
+			break;
+		default:
+			sr_printk(KERN_INFO, cd,
+				  "unsupported sector size %d.", sector_size);
+			cd->capacity = 0;
+		}
+
+		cd->device->sector_size = sector_size;
+
+		/*
+		 * Add this so that we have the ability to correctly gauge
+		 * what the device is capable of.
+		 */
+		set_capacity(cd->disk, cd->capacity);
+	}
+
+	queue = cd->device->request_queue;
+	blk_queue_logical_block_size(queue, sector_size);
+
+	return;
+}
+
+static void get_capabilities(struct scsi_cd *cd)
+{
+	unsigned char *buffer;
+	struct scsi_mode_data data;
+	struct scsi_sense_hdr sshdr;
+	unsigned int ms_len = 128;
+	int rc, n;
+
+	static const char *loadmech[] =
+	{
+		"caddy",
+		"tray",
+		"pop-up",
+		"",
+		"changer",
+		"cartridge changer",
+		"",
+		""
+	};
+
+
+	/* allocate transfer buffer */
+	buffer = kmalloc(512, GFP_KERNEL);
+	if (!buffer) {
+		sr_printk(KERN_ERR, cd, "out of memory.\n");
+		return;
+	}
+
+	/* eat unit attentions */
+	scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
+
+	/* ask for mode page 0x2a */
+	rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, ms_len,
+			     SR_TIMEOUT, 3, &data, NULL);
+
+	if (!scsi_status_is_good(rc) || data.length > ms_len ||
+	    data.header_length + data.block_descriptor_length > data.length) {
+		/* failed, drive doesn't have capabilities mode page */
+		cd->cdi.speed = 1;
+		cd->cdi.mask |= (CDC_CD_R | CDC_CD_RW | CDC_DVD_R |
+				 CDC_DVD | CDC_DVD_RAM |
+				 CDC_SELECT_DISC | CDC_SELECT_SPEED |
+				 CDC_MRW | CDC_MRW_W | CDC_RAM);
+		kfree(buffer);
+		sr_printk(KERN_INFO, cd, "scsi-1 drive");
+		return;
+	}
+
+	n = data.header_length + data.block_descriptor_length;
+	cd->cdi.speed = ((buffer[n + 8] << 8) + buffer[n + 9]) / 176;
+	cd->readcd_known = 1;
+	cd->readcd_cdda = buffer[n + 5] & 0x01;
+	/* print some capability bits */
+	sr_printk(KERN_INFO, cd,
+		  "scsi3-mmc drive: %dx/%dx %s%s%s%s%s%s\n",
+		  ((buffer[n + 14] << 8) + buffer[n + 15]) / 176,
+		  cd->cdi.speed,
+		  buffer[n + 3] & 0x01 ? "writer " : "", /* CD Writer */
+		  buffer[n + 3] & 0x20 ? "dvd-ram " : "",
+		  buffer[n + 2] & 0x02 ? "cd/rw " : "", /* can read rewriteable */
+		  buffer[n + 4] & 0x20 ? "xa/form2 " : "",	/* can read xa/from2 */
+		  buffer[n + 5] & 0x01 ? "cdda " : "", /* can read audio data */
+		  loadmech[buffer[n + 6] >> 5]);
+	if ((buffer[n + 6] >> 5) == 0)
+		/* caddy drives can't close tray... */
+		cd->cdi.mask |= CDC_CLOSE_TRAY;
+	if ((buffer[n + 2] & 0x8) == 0)
+		/* not a DVD drive */
+		cd->cdi.mask |= CDC_DVD;
+	if ((buffer[n + 3] & 0x20) == 0)
+		/* can't write DVD-RAM media */
+		cd->cdi.mask |= CDC_DVD_RAM;
+	if ((buffer[n + 3] & 0x10) == 0)
+		/* can't write DVD-R media */
+		cd->cdi.mask |= CDC_DVD_R;
+	if ((buffer[n + 3] & 0x2) == 0)
+		/* can't write CD-RW media */
+		cd->cdi.mask |= CDC_CD_RW;
+	if ((buffer[n + 3] & 0x1) == 0)
+		/* can't write CD-R media */
+		cd->cdi.mask |= CDC_CD_R;
+	if ((buffer[n + 6] & 0x8) == 0)
+		/* can't eject */
+		cd->cdi.mask |= CDC_OPEN_TRAY;
+
+	if ((buffer[n + 6] >> 5) == mechtype_individual_changer ||
+	    (buffer[n + 6] >> 5) == mechtype_cartridge_changer)
+		cd->cdi.capacity =
+		    cdrom_number_of_slots(&cd->cdi);
+	if (cd->cdi.capacity <= 1)
+		/* not a changer */
+		cd->cdi.mask |= CDC_SELECT_DISC;
+	/*else    I don't think it can close its tray
+		cd->cdi.mask |= CDC_CLOSE_TRAY; */
+
+	/*
+	 * if DVD-RAM, MRW-W or CD-RW, we are randomly writable
+	 */
+	if ((cd->cdi.mask & (CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) !=
+			(CDC_DVD_RAM | CDC_MRW_W | CDC_RAM | CDC_CD_RW)) {
+		cd->writeable = 1;
+	}
+
+	kfree(buffer);
+}
+
+/*
+ * sr_packet() is the entry point for the generic commands generated
+ * by the Uniform CD-ROM layer.
+ */
+static int sr_packet(struct cdrom_device_info *cdi,
+		struct packet_command *cgc)
+{
+	struct scsi_cd *cd = cdi->handle;
+	struct scsi_device *sdev = cd->device;
+
+	if (cgc->cmd[0] == GPCMD_READ_DISC_INFO && sdev->no_read_disc_info)
+		return -EDRIVE_CANT_DO_THIS;
+
+	if (cgc->timeout <= 0)
+		cgc->timeout = IOCTL_TIMEOUT;
+
+	sr_do_ioctl(cd, cgc);
+
+	return cgc->stat;
+}
+
+/**
+ *	sr_kref_release - Called to free the scsi_cd structure
+ *	@kref: pointer to embedded kref
+ *
+ *	sr_ref_mutex must be held entering this routine.  Because it is
+ *	called on last put, you should always use the scsi_cd_get()
+ *	scsi_cd_put() helpers which manipulate the semaphore directly
+ *	and never do a direct kref_put().
+ **/
+static void sr_kref_release(struct kref *kref)
+{
+	struct scsi_cd *cd = container_of(kref, struct scsi_cd, kref);
+	struct gendisk *disk = cd->disk;
+
+	spin_lock(&sr_index_lock);
+	clear_bit(MINOR(disk_devt(disk)), sr_index_bits);
+	spin_unlock(&sr_index_lock);
+
+	unregister_cdrom(&cd->cdi);
+
+	disk->private_data = NULL;
+
+	put_disk(disk);
+
+	kfree(cd);
+}
+
+static int sr_remove(struct device *dev)
+{
+	struct scsi_cd *cd = dev_get_drvdata(dev);
+
+	scsi_autopm_get_device(cd->device);
+
+	del_gendisk(cd->disk);
+	dev_set_drvdata(dev, NULL);
+
+	mutex_lock(&sr_ref_mutex);
+	kref_put(&cd->kref, sr_kref_release);
+	mutex_unlock(&sr_ref_mutex);
+
+	return 0;
+}
+
+static int __init init_sr(void)
+{
+	int rc;
+
+	rc = register_blkdev(SCSI_CDROM_MAJOR, "sr");
+	if (rc)
+		return rc;
+	rc = scsi_register_driver(&sr_template.gendrv);
+	if (rc)
+		unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
+
+	return rc;
+}
+
+static void __exit exit_sr(void)
+{
+	scsi_unregister_driver(&sr_template.gendrv);
+	unregister_blkdev(SCSI_CDROM_MAJOR, "sr");
+}
+
+module_init(init_sr);
+module_exit(exit_sr);
+MODULE_LICENSE("GPL");