kernel-ark/drivers/scsi/sr.c
Linus Torvalds 7b3d9545f9 Revert "scsi: revert "[SCSI] Get rid of scsi_cmnd->done""
This reverts commit ac40532ef0, which gets
us back the original cleanup of 6f5391c283.

It turns out that the bug that was triggered by that commit was
apparently not actually triggered by that commit at all, and just the
testing conditions had changed enough to make it appear to be due to it.

The real problem seems to have been found by Peter Osterlund:

  "pktcdvd sets it [block device size] when opening the /dev/pktcdvd
   device, but when the drive is later opened as /dev/scd0, there is
   nothing that sets it back.  (Btw, 40944 is possible if the disk is a
   CDRW that was formatted with "cdrwtool -m 10236".)

   The problem is that pktcdvd opens the cd device in non-blocking mode
   when pktsetup is run, and doesn't close it again until pktsetup -d is
   run.  The effect is that if you meanwhile open the cd device,
   blkdev.c:do_open() doesn't call bd_set_size() because
   bdev->bd_openers is non-zero."

In particular, to repeat the bug (regardless of whether commit
6f5391c283 is applied or not):

  " 1. Start with an empty drive.
    2. pktsetup 0 /dev/scd0
    3. Insert a CD containing an isofs filesystem.
    4. mount /dev/pktcdvd/0 /mnt/tmp
    5. umount /mnt/tmp
    6. Press the eject button.
    7. Insert a DVD containing a non-writable filesystem.
    8. mount /dev/scd0 /mnt/tmp
    9. find /mnt/tmp -type f -print0 | xargs -0 sha1sum >/dev/null
    10. If the DVD contains data beyond the physical size of a CD, you
        get I/O errors in the terminal, and dmesg reports lots of
        "attempt to access beyond end of device" errors."

which in turn is because the nested open after the media change won't
cause the size to be set properly (because the original open still holds
the block device, and we only do the bd_set_size() when we don't have
other people holding the device open).

The proper fix for that is probably to just do something like

	bdev->bd_inode->i_size = (loff_t)get_capacity(disk)<<9;

in fs/block_dev.c:do_open() even for the cases where we're not the
original opener (but *not* call bd_set_size(), since that will also
change the block size of the device).

Cc: Peter Osterlund <petero2@telia.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-06 10:17:12 -08:00

916 lines
23 KiB
C

/*
* 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 <asm/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 MAX_RETRIES 3
#define SR_TIMEOUT (30 * HZ)
#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 int sr_probe(struct device *);
static int sr_remove(struct device *);
static int sr_done(struct scsi_cmnd *);
static struct scsi_driver sr_template = {
.owner = THIS_MODULE,
.gendrv = {
.name = "sr",
.probe = sr_probe,
.remove = sr_remove,
},
.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 int sr_media_change(struct cdrom_device_info *, int);
static int sr_packet(struct cdrom_device_info *, struct packet_command *);
static struct cdrom_device_ops sr_dops = {
.open = sr_open,
.release = sr_release,
.drive_status = sr_drive_status,
.media_changed = sr_media_change,
.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);
}
/*
* 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))
goto out_put;
goto out;
out_put:
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);
}
/*
* This function checks to see if the media has been changed in the
* CDROM drive. It is possible that we have already sensed a change,
* or the drive may have sensed one and not yet reported it. We must
* be ready for either case. This function always reports the current
* value of the changed bit. If flag is 0, then the changed bit is reset.
* This function could be done as an ioctl, but we would need to have
* an inode for that to work, and we do not always have one.
*/
static int sr_media_change(struct cdrom_device_info *cdi, int slot)
{
struct scsi_cd *cd = cdi->handle;
int retval;
if (CDSL_CURRENT != slot) {
/* no changer support */
return -EINVAL;
}
retval = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES);
if (retval) {
/* Unable to test, unit probably not ready. This usually
* means there is no disc in the drive. Mark as changed,
* and we will figure it out later once the drive is
* available again. */
cd->device->changed = 1;
return 1; /* This will force a flush, if called from
* check_disk_change */
};
retval = cd->device->changed;
cd->device->changed = 0;
/* If the disk changed, the capacity will now be different,
* so we force a re-read of this information */
if (retval) {
/* check multisession offset etc */
sr_cd_check(cdi);
get_sectorsize(cd);
}
return retval;
}
/*
* 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 = SCpnt->request_bufflen;
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
printk("sr.c 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 - SCpnt->request->sector) << 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:
/*
* An error occured, but it recovered. Inform the
* user, but make sure that it's not treated as a
* hard error.
*/
scsi_print_sense("sr", SCpnt);
SCpnt->result = 0;
SCpnt->sense_buffer[0] = 0x0;
good_bytes = this_count;
break;
default:
break;
}
}
return good_bytes;
}
static int sr_prep_fn(struct request_queue *q, struct request *rq)
{
int block=0, this_count, s_size, timeout = SR_TIMEOUT;
struct scsi_cd *cd;
struct scsi_cmnd *SCpnt;
struct scsi_device *sdp = q->queuedata;
int ret;
if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
ret = scsi_setup_blk_pc_cmnd(sdp, rq);
goto out;
} else if (rq->cmd_type != REQ_TYPE_FS) {
ret = BLKPREP_KILL;
goto out;
}
ret = scsi_setup_fs_cmnd(sdp, rq);
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, printk("Doing sr request, dev = %s, block = %d\n",
cd->disk->disk_name, block));
if (!cd->device || !scsi_device_online(cd->device)) {
SCSI_LOG_HLQUEUE(2, printk("Finishing %ld sectors\n",
rq->nr_sectors));
SCSI_LOG_HLQUEUE(2, printk("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
printk("sr: 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;
}
if (rq_data_dir(rq) == WRITE) {
if (!cd->device->writeable)
goto out;
SCpnt->cmnd[0] = WRITE_10;
SCpnt->sc_data_direction = DMA_TO_DEVICE;
cd->cdi.media_written = 1;
} else if (rq_data_dir(rq) == READ) {
SCpnt->cmnd[0] = READ_10;
SCpnt->sc_data_direction = DMA_FROM_DEVICE;
} else {
blk_dump_rq_flags(rq, "Unknown sr command");
goto out;
}
{
struct scatterlist *sg = SCpnt->request_buffer;
int i, size = 0;
for (i = 0; i < SCpnt->use_sg; i++)
size += sg[i].length;
if (size != SCpnt->request_bufflen && SCpnt->use_sg) {
scmd_printk(KERN_ERR, SCpnt,
"mismatch count %d, bytes %d\n",
size, SCpnt->request_bufflen);
if (SCpnt->request_bufflen > size)
SCpnt->request_bufflen = size;
}
}
/*
* request doesn't start on hw block boundary, add scatter pads
*/
if (((unsigned int)rq->sector % (s_size >> 9)) ||
(SCpnt->request_bufflen % s_size)) {
scmd_printk(KERN_NOTICE, SCpnt, "unaligned transfer\n");
goto out;
}
this_count = (SCpnt->request_bufflen >> 9) / (s_size >> 9);
SCSI_LOG_HLQUEUE(2, printk("%s : %s %d/%ld 512 byte blocks.\n",
cd->cdi.name,
(rq_data_dir(rq) == WRITE) ?
"writing" : "reading",
this_count, rq->nr_sectors));
SCpnt->cmnd[1] = 0;
block = (unsigned int)rq->sector / (s_size >> 9);
if (this_count > 0xffff) {
this_count = 0xffff;
SCpnt->request_bufflen = 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;
SCpnt->timeout_per_command = timeout;
/*
* This indicates that the command is ready from our end to be
* queued.
*/
ret = BLKPREP_OK;
out:
return scsi_prep_return(q, rq, ret);
}
static int sr_block_open(struct inode *inode, struct file *file)
{
struct gendisk *disk = inode->i_bdev->bd_disk;
struct scsi_cd *cd;
int ret = 0;
if(!(cd = scsi_cd_get(disk)))
return -ENXIO;
if((ret = cdrom_open(&cd->cdi, inode, file)) != 0)
scsi_cd_put(cd);
return ret;
}
static int sr_block_release(struct inode *inode, struct file *file)
{
int ret;
struct scsi_cd *cd = scsi_cd(inode->i_bdev->bd_disk);
ret = cdrom_release(&cd->cdi, file);
if(ret)
return ret;
scsi_cd_put(cd);
return 0;
}
static int sr_block_ioctl(struct inode *inode, struct file *file, unsigned cmd,
unsigned long arg)
{
struct scsi_cd *cd = scsi_cd(inode->i_bdev->bd_disk);
struct scsi_device *sdev = cd->device;
void __user *argp = (void __user *)arg;
int ret;
/*
* 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:
return scsi_ioctl(sdev, cmd, argp);
}
ret = cdrom_ioctl(file, &cd->cdi, inode, cmd, arg);
if (ret != -ENOSYS)
return ret;
/*
* ENODEV means that we didn't recognise the ioctl, or that we
* cannot execute it in the current device state. In either
* case fall through to scsi_ioctl, which will return ENDOEV again
* if it doesn't recognise the ioctl
*/
ret = scsi_nonblockable_ioctl(sdev, cmd, argp, NULL);
if (ret != -ENODEV)
return ret;
return scsi_ioctl(sdev, cmd, argp);
}
static int sr_block_media_changed(struct gendisk *disk)
{
struct scsi_cd *cd = scsi_cd(disk);
return cdrom_media_changed(&cd->cdi);
}
static struct block_device_operations sr_bdops =
{
.owner = THIS_MODULE,
.open = sr_block_open,
.release = sr_block_release,
.ioctl = sr_block_ioctl,
.media_changed = sr_block_media_changed,
/*
* No compat_ioctl for now because sr_block_ioctl never
* seems to pass arbitary 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;
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;
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->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);
blk_queue_prep_rq(sdev->request_queue, sr_prep_fn);
sr_vendor_init(cd);
disk->driverfs_dev = &sdev->sdev_gendev;
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_put;
dev_set_drvdata(dev, cd);
disk->flags |= GENHD_FL_REMOVABLE;
add_disk(disk);
sdev_printk(KERN_DEBUG, sdev,
"Attached scsi CD-ROM %s\n", cd->cdi.name);
return 0;
fail_put:
put_disk(disk);
fail_free:
kfree(cd);
fail:
return error;
}
static void get_sectorsize(struct scsi_cd *cd)
{
unsigned char cmd[10];
unsigned char *buffer;
int the_result, retries = 3;
int sector_size;
struct request_queue *queue;
buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
if (!buffer)
goto Enomem;
do {
cmd[0] = READ_CAPACITY;
memset((void *) &cmd[1], 0, 9);
memset(buffer, 0, 8);
/* Do the command and wait.. */
the_result = scsi_execute_req(cd->device, cmd, DMA_FROM_DEVICE,
buffer, 8, NULL, SR_TIMEOUT,
MAX_RETRIES);
retries--;
} while (the_result && retries);
if (the_result) {
cd->capacity = 0x1fffff;
sector_size = 2048; /* A guess, just in case */
} else {
#if 0
if (cdrom_get_last_written(&cd->cdi,
&cd->capacity))
#endif
cd->capacity = 1 + ((buffer[0] << 24) |
(buffer[1] << 16) |
(buffer[2] << 8) |
buffer[3]);
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:
printk("%s: unsupported sector size %d.\n",
cd->cdi.name, 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_hardsect_size(queue, sector_size);
out:
kfree(buffer);
return;
Enomem:
cd->capacity = 0x1fffff;
cd->device->sector_size = 2048; /* A guess, just in case */
goto out;
}
static void get_capabilities(struct scsi_cd *cd)
{
unsigned char *buffer;
struct scsi_mode_data data;
unsigned char cmd[MAX_COMMAND_SIZE];
struct scsi_sense_hdr sshdr;
unsigned int the_result;
int retries, rc, n;
static const char *loadmech[] =
{
"caddy",
"tray",
"pop-up",
"",
"changer",
"cartridge changer",
"",
""
};
/* allocate transfer buffer */
buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
if (!buffer) {
printk(KERN_ERR "sr: out of memory.\n");
return;
}
/* issue TEST_UNIT_READY until the initial startup UNIT_ATTENTION
* conditions are gone, or a timeout happens
*/
retries = 0;
do {
memset((void *)cmd, 0, MAX_COMMAND_SIZE);
cmd[0] = TEST_UNIT_READY;
the_result = scsi_execute_req (cd->device, cmd, DMA_NONE, NULL,
0, &sshdr, SR_TIMEOUT,
MAX_RETRIES);
retries++;
} while (retries < 5 &&
(!scsi_status_is_good(the_result) ||
(scsi_sense_valid(&sshdr) &&
sshdr.sense_key == UNIT_ATTENTION)));
/* ask for mode page 0x2a */
rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, 128,
SR_TIMEOUT, 3, &data, NULL);
if (!scsi_status_is_good(rc)) {
/* 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);
printk("%s: scsi-1 drive\n", cd->cdi.name);
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 */
printk("%s: scsi3-mmc drive: %dx/%dx %s%s%s%s%s%s\n", cd->cdi.name,
((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->device->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)
{
if (cgc->timeout <= 0)
cgc->timeout = IOCTL_TIMEOUT;
sr_do_ioctl(cdi->handle, 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(disk->first_minor, 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);
del_gendisk(cd->disk);
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");