// SPDX-License-Identifier: GPL-2.0
/*
* gendisk handling
*
* Portions Copyright (C) 2020 Christoph Hellwig
*/
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/fs.h>
#include <linux/kdev_t.h>
#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/major.h>
#include <linux/mutex.h>
#include <linux/idr.h>
#include <linux/log2.h>
#include <linux/pm_runtime.h>
#include <linux/badblocks.h>
#include <linux/part_stat.h>
#include <linux/blktrace_api.h>
#include "blk-throttle.h"
#include "blk.h"
#include "blk-mq-sched.h"
#include "blk-rq-qos.h"
#include "blk-cgroup.h"
static struct kobject *block_depr;
/*
* Unique, monotonically increasing sequential number associated with block
* devices instances (i.e. incremented each time a device is attached).
* Associating uevents with block devices in userspace is difficult and racy:
* the uevent netlink socket is lossy, and on slow and overloaded systems has
* a very high latency.
* Block devices do not have exclusive owners in userspace, any process can set
* one up (e.g. loop devices). Moreover, device names can be reused (e.g. loop0
* can be reused again and again).
* A userspace process setting up a block device and watching for its events
* cannot thus reliably tell whether an event relates to the device it just set
* up or another earlier instance with the same name.
* This sequential number allows userspace processes to solve this problem, and
* uniquely associate an uevent to the lifetime to a device.
*/
static atomic64_t diskseq;
/* for extended dynamic devt allocation, currently only one major is used */
#define NR_EXT_DEVT (1 << MINORBITS)
static DEFINE_IDA(ext_devt_ida);
void set_capacity(struct gendisk *disk, sector_t sectors)
{
bdev_set_nr_sectors(disk->part0, sectors);
}
EXPORT_SYMBO