cregit-Linux how code gets into the kernel

Release 4.11 drivers/scsi/sr.c

Directory: drivers/scsi
/*
 *  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);
}


Contributors
PersonTokensPropCommitsCommitProp
James Bottomley27100.00%2100.00%


Total27100.00%2100.00%






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;
}


Contributors
PersonTokensPropCommitsCommitProp
Aaron Lu3579.55%150.00%


Alan Stern920.45%150.00%


Total44100.00%2100.00%



/*
 * 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;
}


Contributors
PersonTokensPropCommitsCommitProp
James Bottomley8089.89%342.86%


Arjan van de Ven44.49%114.29%


Greg Kroah-Hartman33.37%228.57%


Aaron Lu22.25%114.29%


Total89100.00%7100.00%






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);
}


Contributors
PersonTokensPropCommitsCommitProp
James Bottomley4187.23%466.67%


Arjan van de Ven48.51%116.67%


Greg Kroah-Hartman24.26%116.67%


Total47100.00%6100.00%






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;
	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Tejun Heo194100.00%1100.00%


Total194100.00%1100.00%



/*
 * 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;
}


Contributors
PersonTokensPropCommitsCommitProp
Kay Sievers14548.82%214.29%


Tejun Heo7525.25%321.43%


Linus Torvalds (pre-git)4414.81%321.43%


James Bottomley186.06%17.14%


Christoph Hellwig82.69%214.29%


Al Viro51.68%17.14%


Adrian Bunk10.34%17.14%


Hannes Reinecke10.34%17.14%


Total297100.00%14100.00%



/*
 * 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;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)20165.05%628.57%


Mike Anderson4414.24%14.76%


Al Viro216.80%523.81%


Jens Axboe113.56%14.76%


Linus Torvalds92.91%29.52%


Christoph Hellwig82.59%29.52%


Hannes Reinecke61.94%14.76%


Tejun Heo30.97%14.76%


James Bottomley30.97%14.76%


Boaz Harrosh30.97%14.76%


Total309100.00%21100.00%






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;
	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;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)33650.00%722.58%


James Bottomley8813.10%412.90%


Alan Stern558.18%13.23%


Linus Torvalds558.18%412.90%


Boaz Harrosh395.80%13.23%


Christoph Hellwig314.61%516.13%


Hannes Reinecke263.87%13.23%


Tejun Heo131.93%13.23%


Al Viro101.49%412.90%


Andrew Morton81.19%13.23%


Peter Osterlund81.19%13.23%


Jeff Garzik30.45%13.23%


Total672100.00%31100.00%






static int sr_block_open(struct block_device *bdev, fmode_t mode)
{
	struct scsi_cd *cd;
	int ret = -ENXIO;

	mutex_lock(&sr_mutex);
	cd = scsi_cd_get(bdev->bd_disk);
	if (cd) {
		ret = cdrom_open(&cd->cdi, bdev, mode);
		if (ret)
			scsi_cd_put(cd);
	}
	mutex_unlock(&sr_mutex);
	return ret;
}


Contributors
PersonTokensPropCommitsCommitProp
Al Viro3747.44%233.33%


Arnd Bergmann2126.92%233.33%


James Bottomley1924.36%116.67%


Christoph Hellwig11.28%116.67%


Total78100.00%6100.00%






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);
}


Contributors
PersonTokensPropCommitsCommitProp
Al Viro3160.78%450.00%


Arnd Bergmann1223.53%225.00%


James Bottomley611.76%112.50%


Christoph Hellwig23.92%112.50%


Total51100.00%8100.00%






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;

	/*
         * 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 out;
	}

	ret = cdrom_ioctl(&cd->cdi, bdev, mode, cmd, arg);
	if (ret != -ENOSYS)
		goto out;

	ret = scsi_ioctl(sdev, cmd, argp);

out:
	mutex_unlock(&sr_mutex);
	return ret;
}


Contributors
PersonTokensPropCommitsCommitProp
Christoph Hellwig6137.20%327.27%


Al Viro4728.66%436.36%


Douglas Gilbert2817.07%19.09%


Arnd Bergmann2716.46%218.18%


Tejun Heo10.61%19.09%


Total164100.00%11100.00%






static unsigned int sr_block_check_events(struct gendisk *disk,
					  unsigned int clearing)
{
	struct scsi_cd *cd = scsi_cd(disk);

	if (atomic_read(&cd->device->disk_events_disable_depth))
		return 0;

	return cdrom_check_events(&cd->cdi, clearing);
}


Contributors
PersonTokensPropCommitsCommitProp
Al Viro2548.08%233.33%


Aaron Lu1630.77%233.33%


Tejun Heo917.31%116.67%


Christoph Hellwig23.85%116.67%


Total52100.00%6100.00%






static int sr_block_revalidate_disk(struct gendisk *disk)
{
	struct scsi_cd *cd = scsi_cd(disk);
	struct scsi_sense_hdr sshdr;

	/* 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:
	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Tejun Heo5892.06%150.00%


Aaron Lu57.94%150.00%


Total63100.00%2100.00%




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;	
}


Contributors
PersonTokensPropCommitsCommitProp
Christoph Hellwig3355.00%342.86%


Linus Torvalds (pre-git)2338.33%228.57%


Doug Ledford23.33%114.29%


Al Viro23.33%114.29%


Total60100.00%7100.00%






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);

}


Contributors
PersonTokensPropCommitsCommitProp
Christoph Hellwig3081.08%233.33%


Linus Torvalds (pre-git)410.81%233.33%


Al Viro38.11%233.33%


Total37100.00%6100.00%






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;