/*
* Slow path for ioc release in put_io_context(). Performs double-lock
* dancing to unlink all icq's and then frees ioc.
*/
static void ioc_release_fn(struct work_struct *work)
{
struct io_context *ioc = container_of(work, struct io_context,
release_work);
struct request_queue *last_q = NULL;
spin_lock_irq(&ioc->lock);
while (!hlist_empty(&ioc->icq_list)) {
struct io_cq *icq = hlist_entry(ioc->icq_list.first,
struct io_cq, ioc_node);
struct request_queue *this_q = icq->q;
if (this_q != last_q) {
/*
* Need to switch to @this_q. Once we release
* @ioc->lock, it can go away along with @cic.
* Hold on to it.
*/
__blk_get_queue(this_q);
/*
* blk_put_queue() might sleep thanks to kobject
* idiocy. Always release both locks, put and
* restart.
*/
if (last_q) {
spin_unlock(last_q->queue_lock);
spin_unlock_irq(&ioc->lock);
blk_put_queue(last_q);
} else {
spin_unlock_irq(&ioc->lock);
}
last_q = this_q;
spin_lock_irq(this_q->queue_lock);
spin_lock(&ioc->lock);
continue;
}
ioc_exit_icq(icq);
}
if (last_q) {
spin_unlock(last_q->queue_lock);
spin_unlock_irq(&ioc->lock);
blk_put_queue(last_q);
} else {
spin_unlock_irq(&ioc->lock);
}
kmem_cache_free(iocontext_cachep, ioc);
}
static void free_dev(struct mapped_device *md)
{
free_minor(md->disk->first_minor);
mempool_destroy(md->tio_pool);
mempool_destroy(md->io_pool);
del_gendisk(md->disk);
put_disk(md->disk);
blk_put_queue(md->queue);
kfree(md);
}
static void free_dev(struct mapped_device *md)
{
unsigned int minor = md->disk->first_minor;
if (md->suspended_bdev) {
thaw_bdev(md->suspended_bdev, NULL);
bdput(md->suspended_bdev);
}
mempool_destroy(md->tio_pool);
mempool_destroy(md->io_pool);
del_gendisk(md->disk);
free_minor(minor);
put_disk(md->disk);
blk_put_queue(md->queue);
kfree(md);
}
int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
unsigned int cmd, void __user *arg)
{
int err;
if (!q || blk_get_queue(q))
return -ENXIO;
switch (cmd) {
/*
* new sgv3 interface
*/
case SG_GET_VERSION_NUM:
err = sg_get_version(arg);
break;
case SCSI_IOCTL_GET_IDLUN:
err = scsi_get_idlun(q, arg);
break;
case SCSI_IOCTL_GET_BUS_NUMBER:
err = scsi_get_bus(q, arg);
break;
case SG_SET_TIMEOUT:
err = sg_set_timeout(q, arg);
break;
case SG_GET_TIMEOUT:
err = sg_get_timeout(q);
break;
case SG_GET_RESERVED_SIZE:
err = sg_get_reserved_size(q, arg);
break;
case SG_SET_RESERVED_SIZE:
err = sg_set_reserved_size(q, arg);
break;
case SG_EMULATED_HOST:
err = sg_emulated_host(q, arg);
break;
case SG_IO: {
struct sg_io_hdr hdr;
err = -EFAULT;
if (copy_from_user(&hdr, arg, sizeof(hdr)))
break;
err = sg_io(q, bd_disk, &hdr, mode);
if (err == -EFAULT)
break;
if (copy_to_user(arg, &hdr, sizeof(hdr)))
err = -EFAULT;
break;
}
case CDROM_SEND_PACKET: {
struct cdrom_generic_command cgc;
struct sg_io_hdr hdr;
err = -EFAULT;
if (copy_from_user(&cgc, arg, sizeof(cgc)))
break;
cgc.timeout = clock_t_to_jiffies(cgc.timeout);
memset(&hdr, 0, sizeof(hdr));
hdr.interface_id = 'S';
hdr.cmd_len = sizeof(cgc.cmd);
hdr.dxfer_len = cgc.buflen;
err = 0;
switch (cgc.data_direction) {
case CGC_DATA_UNKNOWN:
hdr.dxfer_direction = SG_DXFER_UNKNOWN;
break;
case CGC_DATA_WRITE:
hdr.dxfer_direction = SG_DXFER_TO_DEV;
break;
case CGC_DATA_READ:
hdr.dxfer_direction = SG_DXFER_FROM_DEV;
break;
case CGC_DATA_NONE:
hdr.dxfer_direction = SG_DXFER_NONE;
break;
default:
err = -EINVAL;
}
if (err)
break;
hdr.dxferp = cgc.buffer;
hdr.sbp = cgc.sense;
if (hdr.sbp)
hdr.mx_sb_len = sizeof(struct request_sense);
hdr.timeout = jiffies_to_msecs(cgc.timeout);
hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
hdr.cmd_len = sizeof(cgc.cmd);
err = sg_io(q, bd_disk, &hdr, mode);
if (err == -EFAULT)
break;
if (hdr.status)
err = -EIO;
cgc.stat = err;
cgc.buflen = hdr.resid;
if (copy_to_user(arg, &cgc, sizeof(cgc)))
err = -EFAULT;
break;
}
/*
* old junk scsi send command ioctl
*/
case SCSI_IOCTL_SEND_COMMAND:
printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
err = -EINVAL;
if (!arg)
break;
err = sg_scsi_ioctl(q, bd_disk, mode, arg);
break;
case CDROMCLOSETRAY:
err = blk_send_start_stop(q, bd_disk, 0x03);
break;
case CDROMEJECT:
err = blk_send_start_stop(q, bd_disk, 0x02);
break;
default:
err = -ENOTTY;
}
blk_put_queue(q);
return err;
}
/*
* Allocate and initialise a blank device with a given minor.
*/
static struct mapped_device *alloc_dev(unsigned int minor, int persistent)
{
int r;
struct mapped_device *md = kmalloc(sizeof(*md), GFP_KERNEL);
if (!md) {
DMWARN("unable to allocate device, out of memory.");
return NULL;
}
/* get a minor number for the dev */
r = persistent ? specific_minor(minor) : next_free_minor(&minor);
if (r < 0)
goto bad1;
memset(md, 0, sizeof(*md));
init_rwsem(&md->lock);
rwlock_init(&md->map_lock);
atomic_set(&md->holders, 1);
md->queue = blk_alloc_queue(GFP_KERNEL);
if (!md->queue)
goto bad1;
md->queue->queuedata = md;
md->queue->backing_dev_info.congested_fn = dm_any_congested;
md->queue->backing_dev_info.congested_data = md;
blk_queue_make_request(md->queue, dm_request);
md->queue->unplug_fn = dm_unplug_all;
md->io_pool = mempool_create(MIN_IOS, mempool_alloc_slab,
mempool_free_slab, _io_cache);
if (!md->io_pool)
goto bad2;
md->tio_pool = mempool_create(MIN_IOS, mempool_alloc_slab,
mempool_free_slab, _tio_cache);
if (!md->tio_pool)
goto bad3;
md->disk = alloc_disk(1);
if (!md->disk)
goto bad4;
md->disk->major = _major;
md->disk->first_minor = minor;
md->disk->fops = &dm_blk_dops;
md->disk->queue = md->queue;
md->disk->private_data = md;
sprintf(md->disk->disk_name, "dm-%d", minor);
add_disk(md->disk);
atomic_set(&md->pending, 0);
init_waitqueue_head(&md->wait);
init_waitqueue_head(&md->eventq);
return md;
bad4:
mempool_destroy(md->tio_pool);
bad3:
mempool_destroy(md->io_pool);
bad2:
blk_put_queue(md->queue);
free_minor(minor);
bad1:
kfree(md);
return NULL;
}
int scsi_cmd_ioctl(struct file *file, struct gendisk *bd_disk, unsigned int cmd, void __user *arg)
{
request_queue_t *q;
struct request *rq;
int close = 0, err;
q = bd_disk->queue;
if (!q)
return -ENXIO;
if (blk_get_queue(q))
return -ENXIO;
switch (cmd) {
/*
* new sgv3 interface
*/
case SG_GET_VERSION_NUM:
err = sg_get_version(arg);
break;
case SCSI_IOCTL_GET_IDLUN:
err = scsi_get_idlun(q, arg);
break;
case SCSI_IOCTL_GET_BUS_NUMBER:
err = scsi_get_bus(q, arg);
break;
case SG_SET_TIMEOUT:
err = sg_set_timeout(q, arg);
break;
case SG_GET_TIMEOUT:
err = sg_get_timeout(q);
break;
case SG_GET_RESERVED_SIZE:
err = sg_get_reserved_size(q, arg);
break;
case SG_SET_RESERVED_SIZE:
err = sg_set_reserved_size(q, arg);
break;
case SG_EMULATED_HOST:
err = sg_emulated_host(q, arg);
break;
case SG_IO: {
struct sg_io_hdr hdr;
err = -EFAULT;
if (copy_from_user(&hdr, arg, sizeof(hdr)))
break;
err = sg_io(file, q, bd_disk, &hdr);
if (err == -EFAULT)
break;
if (copy_to_user(arg, &hdr, sizeof(hdr)))
err = -EFAULT;
break;
}
case CDROM_SEND_PACKET: {
struct cdrom_generic_command cgc;
struct sg_io_hdr hdr;
err = -EFAULT;
if (copy_from_user(&cgc, arg, sizeof(cgc)))
break;
cgc.timeout = clock_t_to_jiffies(cgc.timeout);
memset(&hdr, 0, sizeof(hdr));
hdr.interface_id = 'S';
hdr.cmd_len = sizeof(cgc.cmd);
hdr.dxfer_len = cgc.buflen;
err = 0;
switch (cgc.data_direction) {
case CGC_DATA_UNKNOWN:
hdr.dxfer_direction = SG_DXFER_UNKNOWN;
break;
case CGC_DATA_WRITE:
hdr.dxfer_direction = SG_DXFER_TO_DEV;
break;
case CGC_DATA_READ:
hdr.dxfer_direction = SG_DXFER_FROM_DEV;
break;
case CGC_DATA_NONE:
hdr.dxfer_direction = SG_DXFER_NONE;
break;
default:
err = -EINVAL;
}
if (err)
break;
hdr.dxferp = cgc.buffer;
hdr.sbp = cgc.sense;
if (hdr.sbp)
hdr.mx_sb_len = sizeof(struct request_sense);
hdr.timeout = cgc.timeout;
hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
hdr.cmd_len = sizeof(cgc.cmd);
err = sg_io(file, q, bd_disk, &hdr);
if (err == -EFAULT)
break;
if (hdr.status)
err = -EIO;
cgc.stat = err;
cgc.buflen = hdr.resid;
if (copy_to_user(arg, &cgc, sizeof(cgc)))
err = -EFAULT;
break;
}
/*
* old junk scsi send command ioctl
*/
case SCSI_IOCTL_SEND_COMMAND:
err = -EINVAL;
if (!arg)
break;
err = sg_scsi_ioctl(file, q, bd_disk, arg);
break;
case CDROMCLOSETRAY:
close = 1;
case CDROMEJECT:
rq = blk_get_request(q, WRITE, __GFP_WAIT);
rq->flags |= REQ_BLOCK_PC;
rq->data = NULL;
rq->data_len = 0;
rq->timeout = BLK_DEFAULT_TIMEOUT;
memset(rq->cmd, 0, sizeof(rq->cmd));
rq->cmd[0] = GPCMD_START_STOP_UNIT;
rq->cmd[4] = 0x02 + (close != 0);
rq->cmd_len = 6;
err = blk_execute_rq(q, bd_disk, rq);
blk_put_request(rq);
break;
default:
err = -ENOTTY;
}
blk_put_queue(q);
return err;
}
