static int max_part;
static int part_shift;
-static struct workqueue_struct *loop_wq;
-
static int transfer_xor(struct loop_device *lo, int cmd,
struct page *raw_page, unsigned raw_off,
struct page *loop_page, unsigned loop_off,
size = get_loop_size(lo, file);
if ((loff_t)(sector_t)size != size)
goto out_putf;
+ error = -ENOMEM;
+ lo->wq = alloc_workqueue("kloopd%d",
+ WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, 16,
+ lo->lo_number);
+ if (!lo->wq)
+ goto out_putf;
error = 0;
* <dev>/do something like mkfs/losetup -d <dev> causing the losetup -d
* command to fail with EBUSY.
*/
- if (lo->lo_refcnt > 1) {
+ if (atomic_read(&lo->lo_refcnt) > 1) {
lo->lo_flags |= LO_FLAGS_AUTOCLEAR;
mutex_unlock(&lo->lo_ctl_mutex);
return 0;
if (filp == NULL)
return -EINVAL;
+ /* freeze request queue during the transition */
+ blk_mq_freeze_queue(lo->lo_queue);
+
spin_lock_irq(&lo->lo_lock);
lo->lo_state = Lo_rundown;
lo->lo_backing_file = NULL;
lo->lo_state = Lo_unbound;
/* This is safe: open() is still holding a reference. */
module_put(THIS_MODULE);
+ blk_mq_unfreeze_queue(lo->lo_queue);
+
if (lo->lo_flags & LO_FLAGS_PARTSCAN && bdev)
ioctl_by_bdev(bdev, BLKRRPART, 0);
lo->lo_flags = 0;
if (!part_shift)
lo->lo_disk->flags |= GENHD_FL_NO_PART_SCAN;
+ destroy_workqueue(lo->wq);
+ lo->wq = NULL;
mutex_unlock(&lo->lo_ctl_mutex);
/*
* Need not hold lo_ctl_mutex to fput backing file.
goto out;
}
- mutex_lock(&lo->lo_ctl_mutex);
- lo->lo_refcnt++;
- mutex_unlock(&lo->lo_ctl_mutex);
+ atomic_inc(&lo->lo_refcnt);
out:
mutex_unlock(&loop_index_mutex);
return err;
struct loop_device *lo = disk->private_data;
int err;
- mutex_lock(&lo->lo_ctl_mutex);
-
- if (--lo->lo_refcnt)
- goto out;
+ if (atomic_dec_return(&lo->lo_refcnt))
+ return;
+ mutex_lock(&lo->lo_ctl_mutex);
if (lo->lo_flags & LO_FLAGS_AUTOCLEAR) {
/*
* In autoclear mode, stop the loop thread
const struct blk_mq_queue_data *bd)
{
struct loop_cmd *cmd = blk_mq_rq_to_pdu(bd->rq);
+ struct loop_device *lo = cmd->rq->q->queuedata;
blk_mq_start_request(bd->rq);
+ if (lo->lo_state != Lo_bound)
+ return -EIO;
+
if (cmd->rq->cmd_flags & REQ_WRITE) {
struct loop_device *lo = cmd->rq->q->queuedata;
bool need_sched = true;
spin_unlock_irq(&lo->lo_lock);
if (need_sched)
- queue_work(loop_wq, &lo->write_work);
+ queue_work(lo->wq, &lo->write_work);
} else {
- queue_work(loop_wq, &cmd->read_work);
+ queue_work(lo->wq, &cmd->read_work);
}
return BLK_MQ_RQ_QUEUE_OK;
struct loop_device *lo = cmd->rq->q->queuedata;
int ret = -EIO;
- if (lo->lo_state != Lo_bound)
- goto failed;
-
if (write && (lo->lo_flags & LO_FLAGS_READ_ONLY))
goto failed;
disk->flags |= GENHD_FL_NO_PART_SCAN;
disk->flags |= GENHD_FL_EXT_DEVT;
mutex_init(&lo->lo_ctl_mutex);
+ atomic_set(&lo->lo_refcnt, 0);
lo->lo_number = i;
spin_lock_init(&lo->lo_lock);
disk->major = LOOP_MAJOR;
mutex_unlock(&lo->lo_ctl_mutex);
break;
}
- if (lo->lo_refcnt > 0) {
+ if (atomic_read(&lo->lo_refcnt) > 0) {
ret = -EBUSY;
mutex_unlock(&lo->lo_ctl_mutex);
break;
goto misc_out;
}
- loop_wq = alloc_workqueue("kloopd",
- WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, 0);
- if (!loop_wq) {
- err = -ENOMEM;
- goto misc_out;
- }
-
blk_register_region(MKDEV(LOOP_MAJOR, 0), range,
THIS_MODULE, loop_probe, NULL, NULL);
blk_unregister_region(MKDEV(LOOP_MAJOR, 0), range);
unregister_blkdev(LOOP_MAJOR, "loop");
- destroy_workqueue(loop_wq);
-
misc_deregister(&loop_misc);
}