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OpenCloudOS-Kernel/drivers/scsi/sr.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* 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/blk-pm.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 blk_status_t 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 blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
{
int block = 0, this_count, s_size;
struct scsi_cd *cd;
struct request *rq = SCpnt->request;
blk_status_t ret;
ret = scsi_init_io(SCpnt);
if (ret != BLK_STS_OK)
goto out;
cd = scsi_cd(rq->rq_disk);
/* from here on until we're complete, any goto out
* is used for a killable error condition */
ret = BLK_STS_IOERR;
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 = BLK_STS_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;
disk->event_flags = DISK_EVENT_FLAG_POLL | DISK_EVENT_FLAG_UEVENT;
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");
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