static int zram_remove(struct zram *zram)
{
struct block_device *bdev = zram->disk->part0;
+ bool claimed;
mutex_lock(&bdev->bd_disk->open_mutex);
- if (bdev->bd_openers || zram->claim) {
+ if (bdev->bd_openers) {
mutex_unlock(&bdev->bd_disk->open_mutex);
return -EBUSY;
}
- zram->claim = true;
+ claimed = zram->claim;
+ if (!claimed)
+ zram->claim = true;
mutex_unlock(&bdev->bd_disk->open_mutex);
zram_debugfs_unregister(zram);
- /* Make sure all the pending I/O are finished */
- fsync_bdev(bdev);
- zram_reset_device(zram);
+ if (claimed) {
+ /*
+ * If we were claimed by reset_store(), del_gendisk() will
+ * wait until reset_store() is done, so nothing need to do.
+ */
+ ;
+ } else {
+ /* Make sure all the pending I/O are finished */
+ fsync_bdev(bdev);
+ zram_reset_device(zram);
+ }
pr_info("Removed device: %s\n", zram->disk->disk_name);
del_gendisk(zram->disk);
+
+ /* del_gendisk drains pending reset_store */
+ WARN_ON_ONCE(claimed && zram->claim);
+
blk_cleanup_disk(zram->disk);
kfree(zram);
return 0;
static int zram_remove_cb(int id, void *ptr, void *data)
{
- zram_remove(ptr);
+ WARN_ON_ONCE(zram_remove(ptr));
return 0;
}