diff options
| author | Christoph Hellwig <hch@lst.de> | 2020-10-29 15:58:33 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-11-16 08:14:30 -0700 |
| commit | 8410d38c255200f71b67ddb37021c36273e7e78c (patch) | |
| tree | baaa2c9770abd1b548fa14e4ad1259b4dfd1a96c /drivers/block/loop.c | |
| parent | 7cc178a6b994b7c994f1811c4b9fedc015ee0c9e (diff) | |
| download | linux-8410d38c255200f71b67ddb37021c36273e7e78c.tar.gz | |
loop: use __register_blkdev to allocate devices on demand
Use the simpler mechanism attached to major_name to allocate a brd device
when a currently unregistered minor is accessed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block/loop.c')
| -rw-r--r-- | drivers/block/loop.c | 30 |
1 files changed, 8 insertions, 22 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 027f5724fe2c46..22e59410b971f7 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -2235,24 +2235,18 @@ out: return ret; } -static struct kobject *loop_probe(dev_t dev, int *part, void *data) +static void loop_probe(dev_t dev) { + int idx = MINOR(dev) >> part_shift; struct loop_device *lo; - struct kobject *kobj; - int err; + + if (max_loop && idx >= max_loop) + return; mutex_lock(&loop_ctl_mutex); - err = loop_lookup(&lo, MINOR(dev) >> part_shift); - if (err < 0) - err = loop_add(&lo, MINOR(dev) >> part_shift); - if (err < 0) - kobj = NULL; - else - kobj = get_disk_and_module(lo->lo_disk); + if (loop_lookup(&lo, idx) < 0) + loop_add(&lo, idx); mutex_unlock(&loop_ctl_mutex); - - *part = 0; - return kobj; } static long loop_control_ioctl(struct file *file, unsigned int cmd, @@ -2372,14 +2366,11 @@ static int __init loop_init(void) goto err_out; - if (register_blkdev(LOOP_MAJOR, "loop")) { + if (__register_blkdev(LOOP_MAJOR, "loop", loop_probe)) { err = -EIO; goto misc_out; } - blk_register_region(MKDEV(LOOP_MAJOR, 0), range, - THIS_MODULE, loop_probe, NULL, NULL); - /* pre-create number of devices given by config or max_loop */ mutex_lock(&loop_ctl_mutex); for (i = 0; i < nr; i++) @@ -2405,16 +2396,11 @@ static int loop_exit_cb(int id, void *ptr, void *data) static void __exit loop_exit(void) { - unsigned long range; - - range = max_loop ? max_loop << part_shift : 1UL << MINORBITS; - mutex_lock(&loop_ctl_mutex); idr_for_each(&loop_index_idr, &loop_exit_cb, NULL); idr_destroy(&loop_index_idr); - blk_unregister_region(MKDEV(LOOP_MAJOR, 0), range); unregister_blkdev(LOOP_MAJOR, "loop"); misc_deregister(&loop_misc); |