1545 строки
39 KiB
C
1545 строки
39 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* gendisk handling
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*
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* Portions Copyright (C) 2020 Christoph Hellwig
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*/
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#include <linux/module.h>
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#include <linux/ctype.h>
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#include <linux/fs.h>
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#include <linux/kdev_t.h>
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#include <linux/kernel.h>
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#include <linux/blkdev.h>
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#include <linux/backing-dev.h>
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#include <linux/init.h>
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#include <linux/spinlock.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/slab.h>
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#include <linux/kmod.h>
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#include <linux/major.h>
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#include <linux/mutex.h>
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#include <linux/idr.h>
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#include <linux/log2.h>
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#include <linux/pm_runtime.h>
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#include <linux/badblocks.h>
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#include <linux/part_stat.h>
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#include "blk-throttle.h"
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#include "blk.h"
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#include "blk-mq-sched.h"
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#include "blk-rq-qos.h"
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#include "blk-cgroup.h"
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static struct kobject *block_depr;
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/*
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* Unique, monotonically increasing sequential number associated with block
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* devices instances (i.e. incremented each time a device is attached).
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* Associating uevents with block devices in userspace is difficult and racy:
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* the uevent netlink socket is lossy, and on slow and overloaded systems has
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* a very high latency.
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* Block devices do not have exclusive owners in userspace, any process can set
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* one up (e.g. loop devices). Moreover, device names can be reused (e.g. loop0
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* can be reused again and again).
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* A userspace process setting up a block device and watching for its events
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* cannot thus reliably tell whether an event relates to the device it just set
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* up or another earlier instance with the same name.
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* This sequential number allows userspace processes to solve this problem, and
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* uniquely associate an uevent to the lifetime to a device.
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*/
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static atomic64_t diskseq;
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/* for extended dynamic devt allocation, currently only one major is used */
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#define NR_EXT_DEVT (1 << MINORBITS)
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static DEFINE_IDA(ext_devt_ida);
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void set_capacity(struct gendisk *disk, sector_t sectors)
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{
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bdev_set_nr_sectors(disk->part0, sectors);
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}
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EXPORT_SYMBOL(set_capacity);
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/*
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* Set disk capacity and notify if the size is not currently zero and will not
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* be set to zero. Returns true if a uevent was sent, otherwise false.
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*/
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bool set_capacity_and_notify(struct gendisk *disk, sector_t size)
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{
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sector_t capacity = get_capacity(disk);
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char *envp[] = { "RESIZE=1", NULL };
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set_capacity(disk, size);
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/*
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* Only print a message and send a uevent if the gendisk is user visible
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* and alive. This avoids spamming the log and udev when setting the
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* initial capacity during probing.
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*/
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if (size == capacity ||
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!disk_live(disk) ||
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(disk->flags & GENHD_FL_HIDDEN))
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return false;
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pr_info("%s: detected capacity change from %lld to %lld\n",
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disk->disk_name, capacity, size);
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/*
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* Historically we did not send a uevent for changes to/from an empty
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* device.
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*/
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if (!capacity || !size)
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return false;
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kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp);
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return true;
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}
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EXPORT_SYMBOL_GPL(set_capacity_and_notify);
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static void part_stat_read_all(struct block_device *part,
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struct disk_stats *stat)
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{
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int cpu;
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memset(stat, 0, sizeof(struct disk_stats));
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for_each_possible_cpu(cpu) {
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struct disk_stats *ptr = per_cpu_ptr(part->bd_stats, cpu);
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int group;
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for (group = 0; group < NR_STAT_GROUPS; group++) {
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stat->nsecs[group] += ptr->nsecs[group];
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stat->sectors[group] += ptr->sectors[group];
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stat->ios[group] += ptr->ios[group];
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stat->merges[group] += ptr->merges[group];
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}
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stat->io_ticks += ptr->io_ticks;
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}
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}
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static unsigned int part_in_flight(struct block_device *part)
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{
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unsigned int inflight = 0;
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int cpu;
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for_each_possible_cpu(cpu) {
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inflight += part_stat_local_read_cpu(part, in_flight[0], cpu) +
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part_stat_local_read_cpu(part, in_flight[1], cpu);
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}
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if ((int)inflight < 0)
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inflight = 0;
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return inflight;
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}
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static void part_in_flight_rw(struct block_device *part,
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unsigned int inflight[2])
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{
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int cpu;
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inflight[0] = 0;
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inflight[1] = 0;
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for_each_possible_cpu(cpu) {
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inflight[0] += part_stat_local_read_cpu(part, in_flight[0], cpu);
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inflight[1] += part_stat_local_read_cpu(part, in_flight[1], cpu);
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}
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if ((int)inflight[0] < 0)
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inflight[0] = 0;
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if ((int)inflight[1] < 0)
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inflight[1] = 0;
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}
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/*
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* Can be deleted altogether. Later.
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*
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*/
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#define BLKDEV_MAJOR_HASH_SIZE 255
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static struct blk_major_name {
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struct blk_major_name *next;
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int major;
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char name[16];
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#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD
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void (*probe)(dev_t devt);
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#endif
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} *major_names[BLKDEV_MAJOR_HASH_SIZE];
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static DEFINE_MUTEX(major_names_lock);
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static DEFINE_SPINLOCK(major_names_spinlock);
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/* index in the above - for now: assume no multimajor ranges */
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static inline int major_to_index(unsigned major)
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{
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return major % BLKDEV_MAJOR_HASH_SIZE;
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}
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#ifdef CONFIG_PROC_FS
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void blkdev_show(struct seq_file *seqf, off_t offset)
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{
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struct blk_major_name *dp;
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spin_lock(&major_names_spinlock);
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for (dp = major_names[major_to_index(offset)]; dp; dp = dp->next)
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if (dp->major == offset)
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seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
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spin_unlock(&major_names_spinlock);
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}
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#endif /* CONFIG_PROC_FS */
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/**
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* __register_blkdev - register a new block device
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*
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* @major: the requested major device number [1..BLKDEV_MAJOR_MAX-1]. If
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* @major = 0, try to allocate any unused major number.
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* @name: the name of the new block device as a zero terminated string
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* @probe: pre-devtmpfs / pre-udev callback used to create disks when their
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* pre-created device node is accessed. When a probe call uses
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* add_disk() and it fails the driver must cleanup resources. This
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* interface may soon be removed.
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*
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* The @name must be unique within the system.
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*
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* The return value depends on the @major input parameter:
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*
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* - if a major device number was requested in range [1..BLKDEV_MAJOR_MAX-1]
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* then the function returns zero on success, or a negative error code
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* - if any unused major number was requested with @major = 0 parameter
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* then the return value is the allocated major number in range
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* [1..BLKDEV_MAJOR_MAX-1] or a negative error code otherwise
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*
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* See Documentation/admin-guide/devices.txt for the list of allocated
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* major numbers.
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*
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* Use register_blkdev instead for any new code.
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*/
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int __register_blkdev(unsigned int major, const char *name,
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void (*probe)(dev_t devt))
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{
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struct blk_major_name **n, *p;
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int index, ret = 0;
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mutex_lock(&major_names_lock);
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/* temporary */
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if (major == 0) {
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for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
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if (major_names[index] == NULL)
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break;
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}
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if (index == 0) {
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printk("%s: failed to get major for %s\n",
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__func__, name);
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ret = -EBUSY;
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goto out;
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}
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major = index;
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ret = major;
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}
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if (major >= BLKDEV_MAJOR_MAX) {
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pr_err("%s: major requested (%u) is greater than the maximum (%u) for %s\n",
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__func__, major, BLKDEV_MAJOR_MAX-1, name);
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ret = -EINVAL;
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goto out;
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}
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p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
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if (p == NULL) {
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ret = -ENOMEM;
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goto out;
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}
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p->major = major;
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#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD
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p->probe = probe;
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#endif
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strscpy(p->name, name, sizeof(p->name));
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p->next = NULL;
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index = major_to_index(major);
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spin_lock(&major_names_spinlock);
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for (n = &major_names[index]; *n; n = &(*n)->next) {
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if ((*n)->major == major)
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break;
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}
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if (!*n)
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*n = p;
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else
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ret = -EBUSY;
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spin_unlock(&major_names_spinlock);
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if (ret < 0) {
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printk("register_blkdev: cannot get major %u for %s\n",
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major, name);
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kfree(p);
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}
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out:
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mutex_unlock(&major_names_lock);
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return ret;
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}
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EXPORT_SYMBOL(__register_blkdev);
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void unregister_blkdev(unsigned int major, const char *name)
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{
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struct blk_major_name **n;
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struct blk_major_name *p = NULL;
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int index = major_to_index(major);
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mutex_lock(&major_names_lock);
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spin_lock(&major_names_spinlock);
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for (n = &major_names[index]; *n; n = &(*n)->next)
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if ((*n)->major == major)
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break;
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if (!*n || strcmp((*n)->name, name)) {
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WARN_ON(1);
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} else {
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p = *n;
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*n = p->next;
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}
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spin_unlock(&major_names_spinlock);
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mutex_unlock(&major_names_lock);
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kfree(p);
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}
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EXPORT_SYMBOL(unregister_blkdev);
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int blk_alloc_ext_minor(void)
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{
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int idx;
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idx = ida_alloc_range(&ext_devt_ida, 0, NR_EXT_DEVT - 1, GFP_KERNEL);
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if (idx == -ENOSPC)
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return -EBUSY;
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return idx;
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}
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void blk_free_ext_minor(unsigned int minor)
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{
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ida_free(&ext_devt_ida, minor);
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}
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static char *bdevt_str(dev_t devt, char *buf)
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{
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if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
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char tbuf[BDEVT_SIZE];
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snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
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snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
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} else
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snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
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return buf;
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}
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void disk_uevent(struct gendisk *disk, enum kobject_action action)
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{
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struct block_device *part;
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unsigned long idx;
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rcu_read_lock();
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xa_for_each(&disk->part_tbl, idx, part) {
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if (bdev_is_partition(part) && !bdev_nr_sectors(part))
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continue;
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if (!kobject_get_unless_zero(&part->bd_device.kobj))
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continue;
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rcu_read_unlock();
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kobject_uevent(bdev_kobj(part), action);
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put_device(&part->bd_device);
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rcu_read_lock();
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}
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rcu_read_unlock();
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}
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EXPORT_SYMBOL_GPL(disk_uevent);
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int disk_scan_partitions(struct gendisk *disk, fmode_t mode)
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{
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struct block_device *bdev;
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int ret = 0;
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if (disk->flags & (GENHD_FL_NO_PART | GENHD_FL_HIDDEN))
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return -EINVAL;
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if (test_bit(GD_SUPPRESS_PART_SCAN, &disk->state))
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return -EINVAL;
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if (disk->open_partitions)
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return -EBUSY;
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/*
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* If the device is opened exclusively by current thread already, it's
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* safe to scan partitons, otherwise, use bd_prepare_to_claim() to
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* synchronize with other exclusive openers and other partition
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* scanners.
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*/
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if (!(mode & FMODE_EXCL)) {
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ret = bd_prepare_to_claim(disk->part0, disk_scan_partitions,
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NULL);
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if (ret)
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return ret;
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}
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set_bit(GD_NEED_PART_SCAN, &disk->state);
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bdev = blkdev_get_by_dev(disk_devt(disk), mode & ~FMODE_EXCL, NULL,
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NULL);
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if (IS_ERR(bdev))
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ret = PTR_ERR(bdev);
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else
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blkdev_put(bdev, mode & ~FMODE_EXCL);
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/*
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* If blkdev_get_by_dev() failed early, GD_NEED_PART_SCAN is still set,
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* and this will cause that re-assemble partitioned raid device will
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* creat partition for underlying disk.
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*/
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clear_bit(GD_NEED_PART_SCAN, &disk->state);
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if (!(mode & FMODE_EXCL))
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bd_abort_claiming(disk->part0, disk_scan_partitions);
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return ret;
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}
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/**
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* device_add_disk - add disk information to kernel list
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* @parent: parent device for the disk
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* @disk: per-device partitioning information
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* @groups: Additional per-device sysfs groups
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*
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* This function registers the partitioning information in @disk
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* with the kernel.
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*/
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int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
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const struct attribute_group **groups)
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{
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struct device *ddev = disk_to_dev(disk);
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int ret;
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/* Only makes sense for bio-based to set ->poll_bio */
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if (queue_is_mq(disk->queue) && disk->fops->poll_bio)
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return -EINVAL;
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/*
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* The disk queue should now be all set with enough information about
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* the device for the elevator code to pick an adequate default
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* elevator if one is needed, that is, for devices requesting queue
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* registration.
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*/
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elevator_init_mq(disk->queue);
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/* Mark bdev as having a submit_bio, if needed */
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disk->part0->bd_has_submit_bio = disk->fops->submit_bio != NULL;
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/*
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* If the driver provides an explicit major number it also must provide
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* the number of minors numbers supported, and those will be used to
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* setup the gendisk.
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* Otherwise just allocate the device numbers for both the whole device
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* and all partitions from the extended dev_t space.
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*/
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ret = -EINVAL;
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if (disk->major) {
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if (WARN_ON(!disk->minors))
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goto out_exit_elevator;
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if (disk->minors > DISK_MAX_PARTS) {
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pr_err("block: can't allocate more than %d partitions\n",
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DISK_MAX_PARTS);
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disk->minors = DISK_MAX_PARTS;
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}
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if (disk->first_minor + disk->minors > MINORMASK + 1)
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goto out_exit_elevator;
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} else {
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if (WARN_ON(disk->minors))
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goto out_exit_elevator;
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ret = blk_alloc_ext_minor();
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if (ret < 0)
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goto out_exit_elevator;
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disk->major = BLOCK_EXT_MAJOR;
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disk->first_minor = ret;
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}
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/* delay uevents, until we scanned partition table */
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dev_set_uevent_suppress(ddev, 1);
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ddev->parent = parent;
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ddev->groups = groups;
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dev_set_name(ddev, "%s", disk->disk_name);
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if (!(disk->flags & GENHD_FL_HIDDEN))
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ddev->devt = MKDEV(disk->major, disk->first_minor);
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ret = device_add(ddev);
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if (ret)
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goto out_free_ext_minor;
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ret = disk_alloc_events(disk);
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if (ret)
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goto out_device_del;
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ret = sysfs_create_link(block_depr, &ddev->kobj,
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kobject_name(&ddev->kobj));
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if (ret)
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goto out_device_del;
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/*
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* avoid probable deadlock caused by allocating memory with
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* GFP_KERNEL in runtime_resume callback of its all ancestor
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* devices
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*/
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pm_runtime_set_memalloc_noio(ddev, true);
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disk->part0->bd_holder_dir =
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kobject_create_and_add("holders", &ddev->kobj);
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if (!disk->part0->bd_holder_dir) {
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ret = -ENOMEM;
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goto out_del_block_link;
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}
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disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
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if (!disk->slave_dir) {
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ret = -ENOMEM;
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goto out_put_holder_dir;
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}
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ret = blk_register_queue(disk);
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if (ret)
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goto out_put_slave_dir;
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if (!(disk->flags & GENHD_FL_HIDDEN)) {
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ret = bdi_register(disk->bdi, "%u:%u",
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disk->major, disk->first_minor);
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if (ret)
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goto out_unregister_queue;
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bdi_set_owner(disk->bdi, ddev);
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ret = sysfs_create_link(&ddev->kobj,
|
|
&disk->bdi->dev->kobj, "bdi");
|
|
if (ret)
|
|
goto out_unregister_bdi;
|
|
|
|
/* Make sure the first partition scan will be proceed */
|
|
if (get_capacity(disk) && !(disk->flags & GENHD_FL_NO_PART) &&
|
|
!test_bit(GD_SUPPRESS_PART_SCAN, &disk->state))
|
|
set_bit(GD_NEED_PART_SCAN, &disk->state);
|
|
|
|
bdev_add(disk->part0, ddev->devt);
|
|
if (get_capacity(disk))
|
|
disk_scan_partitions(disk, FMODE_READ);
|
|
|
|
/*
|
|
* Announce the disk and partitions after all partitions are
|
|
* created. (for hidden disks uevents remain suppressed forever)
|
|
*/
|
|
dev_set_uevent_suppress(ddev, 0);
|
|
disk_uevent(disk, KOBJ_ADD);
|
|
} else {
|
|
/*
|
|
* Even if the block_device for a hidden gendisk is not
|
|
* registered, it needs to have a valid bd_dev so that the
|
|
* freeing of the dynamic major works.
|
|
*/
|
|
disk->part0->bd_dev = MKDEV(disk->major, disk->first_minor);
|
|
}
|
|
|
|
disk_update_readahead(disk);
|
|
disk_add_events(disk);
|
|
set_bit(GD_ADDED, &disk->state);
|
|
return 0;
|
|
|
|
out_unregister_bdi:
|
|
if (!(disk->flags & GENHD_FL_HIDDEN))
|
|
bdi_unregister(disk->bdi);
|
|
out_unregister_queue:
|
|
blk_unregister_queue(disk);
|
|
rq_qos_exit(disk->queue);
|
|
out_put_slave_dir:
|
|
kobject_put(disk->slave_dir);
|
|
disk->slave_dir = NULL;
|
|
out_put_holder_dir:
|
|
kobject_put(disk->part0->bd_holder_dir);
|
|
out_del_block_link:
|
|
sysfs_remove_link(block_depr, dev_name(ddev));
|
|
out_device_del:
|
|
device_del(ddev);
|
|
out_free_ext_minor:
|
|
if (disk->major == BLOCK_EXT_MAJOR)
|
|
blk_free_ext_minor(disk->first_minor);
|
|
out_exit_elevator:
|
|
if (disk->queue->elevator)
|
|
elevator_exit(disk->queue);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(device_add_disk);
|
|
|
|
static void blk_report_disk_dead(struct gendisk *disk)
|
|
{
|
|
struct block_device *bdev;
|
|
unsigned long idx;
|
|
|
|
rcu_read_lock();
|
|
xa_for_each(&disk->part_tbl, idx, bdev) {
|
|
if (!kobject_get_unless_zero(&bdev->bd_device.kobj))
|
|
continue;
|
|
rcu_read_unlock();
|
|
|
|
mutex_lock(&bdev->bd_holder_lock);
|
|
if (bdev->bd_holder_ops && bdev->bd_holder_ops->mark_dead)
|
|
bdev->bd_holder_ops->mark_dead(bdev);
|
|
mutex_unlock(&bdev->bd_holder_lock);
|
|
|
|
put_device(&bdev->bd_device);
|
|
rcu_read_lock();
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* blk_mark_disk_dead - mark a disk as dead
|
|
* @disk: disk to mark as dead
|
|
*
|
|
* Mark as disk as dead (e.g. surprise removed) and don't accept any new I/O
|
|
* to this disk.
|
|
*/
|
|
void blk_mark_disk_dead(struct gendisk *disk)
|
|
{
|
|
/*
|
|
* Fail any new I/O.
|
|
*/
|
|
if (test_and_set_bit(GD_DEAD, &disk->state))
|
|
return;
|
|
|
|
if (test_bit(GD_OWNS_QUEUE, &disk->state))
|
|
blk_queue_flag_set(QUEUE_FLAG_DYING, disk->queue);
|
|
|
|
/*
|
|
* Stop buffered writers from dirtying pages that can't be written out.
|
|
*/
|
|
set_capacity(disk, 0);
|
|
|
|
/*
|
|
* Prevent new I/O from crossing bio_queue_enter().
|
|
*/
|
|
blk_queue_start_drain(disk->queue);
|
|
|
|
blk_report_disk_dead(disk);
|
|
}
|
|
EXPORT_SYMBOL_GPL(blk_mark_disk_dead);
|
|
|
|
/**
|
|
* del_gendisk - remove the gendisk
|
|
* @disk: the struct gendisk to remove
|
|
*
|
|
* Removes the gendisk and all its associated resources. This deletes the
|
|
* partitions associated with the gendisk, and unregisters the associated
|
|
* request_queue.
|
|
*
|
|
* This is the counter to the respective __device_add_disk() call.
|
|
*
|
|
* The final removal of the struct gendisk happens when its refcount reaches 0
|
|
* with put_disk(), which should be called after del_gendisk(), if
|
|
* __device_add_disk() was used.
|
|
*
|
|
* Drivers exist which depend on the release of the gendisk to be synchronous,
|
|
* it should not be deferred.
|
|
*
|
|
* Context: can sleep
|
|
*/
|
|
void del_gendisk(struct gendisk *disk)
|
|
{
|
|
struct request_queue *q = disk->queue;
|
|
struct block_device *part;
|
|
unsigned long idx;
|
|
|
|
might_sleep();
|
|
|
|
if (WARN_ON_ONCE(!disk_live(disk) && !(disk->flags & GENHD_FL_HIDDEN)))
|
|
return;
|
|
|
|
disk_del_events(disk);
|
|
|
|
/*
|
|
* Prevent new openers by unlinked the bdev inode, and write out
|
|
* dirty data before marking the disk dead and stopping all I/O.
|
|
*/
|
|
mutex_lock(&disk->open_mutex);
|
|
xa_for_each(&disk->part_tbl, idx, part) {
|
|
remove_inode_hash(part->bd_inode);
|
|
fsync_bdev(part);
|
|
__invalidate_device(part, true);
|
|
}
|
|
mutex_unlock(&disk->open_mutex);
|
|
|
|
blk_mark_disk_dead(disk);
|
|
|
|
/*
|
|
* Drop all partitions now that the disk is marked dead.
|
|
*/
|
|
mutex_lock(&disk->open_mutex);
|
|
xa_for_each_start(&disk->part_tbl, idx, part, 1)
|
|
drop_partition(part);
|
|
mutex_unlock(&disk->open_mutex);
|
|
|
|
if (!(disk->flags & GENHD_FL_HIDDEN)) {
|
|
sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
|
|
|
|
/*
|
|
* Unregister bdi before releasing device numbers (as they can
|
|
* get reused and we'd get clashes in sysfs).
|
|
*/
|
|
bdi_unregister(disk->bdi);
|
|
}
|
|
|
|
blk_unregister_queue(disk);
|
|
|
|
kobject_put(disk->part0->bd_holder_dir);
|
|
kobject_put(disk->slave_dir);
|
|
disk->slave_dir = NULL;
|
|
|
|
part_stat_set_all(disk->part0, 0);
|
|
disk->part0->bd_stamp = 0;
|
|
sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
|
|
pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
|
|
device_del(disk_to_dev(disk));
|
|
|
|
blk_mq_freeze_queue_wait(q);
|
|
|
|
blk_throtl_cancel_bios(disk);
|
|
|
|
blk_sync_queue(q);
|
|
blk_flush_integrity();
|
|
|
|
if (queue_is_mq(q))
|
|
blk_mq_cancel_work_sync(q);
|
|
|
|
blk_mq_quiesce_queue(q);
|
|
if (q->elevator) {
|
|
mutex_lock(&q->sysfs_lock);
|
|
elevator_exit(q);
|
|
mutex_unlock(&q->sysfs_lock);
|
|
}
|
|
rq_qos_exit(q);
|
|
blk_mq_unquiesce_queue(q);
|
|
|
|
/*
|
|
* If the disk does not own the queue, allow using passthrough requests
|
|
* again. Else leave the queue frozen to fail all I/O.
|
|
*/
|
|
if (!test_bit(GD_OWNS_QUEUE, &disk->state)) {
|
|
blk_queue_flag_clear(QUEUE_FLAG_INIT_DONE, q);
|
|
__blk_mq_unfreeze_queue(q, true);
|
|
} else {
|
|
if (queue_is_mq(q))
|
|
blk_mq_exit_queue(q);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(del_gendisk);
|
|
|
|
/**
|
|
* invalidate_disk - invalidate the disk
|
|
* @disk: the struct gendisk to invalidate
|
|
*
|
|
* A helper to invalidates the disk. It will clean the disk's associated
|
|
* buffer/page caches and reset its internal states so that the disk
|
|
* can be reused by the drivers.
|
|
*
|
|
* Context: can sleep
|
|
*/
|
|
void invalidate_disk(struct gendisk *disk)
|
|
{
|
|
struct block_device *bdev = disk->part0;
|
|
|
|
invalidate_bdev(bdev);
|
|
bdev->bd_inode->i_mapping->wb_err = 0;
|
|
set_capacity(disk, 0);
|
|
}
|
|
EXPORT_SYMBOL(invalidate_disk);
|
|
|
|
/* sysfs access to bad-blocks list. */
|
|
static ssize_t disk_badblocks_show(struct device *dev,
|
|
struct device_attribute *attr,
|
|
char *page)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
if (!disk->bb)
|
|
return sprintf(page, "\n");
|
|
|
|
return badblocks_show(disk->bb, page, 0);
|
|
}
|
|
|
|
static ssize_t disk_badblocks_store(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *page, size_t len)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
if (!disk->bb)
|
|
return -ENXIO;
|
|
|
|
return badblocks_store(disk->bb, page, len, 0);
|
|
}
|
|
|
|
#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD
|
|
void blk_request_module(dev_t devt)
|
|
{
|
|
unsigned int major = MAJOR(devt);
|
|
struct blk_major_name **n;
|
|
|
|
mutex_lock(&major_names_lock);
|
|
for (n = &major_names[major_to_index(major)]; *n; n = &(*n)->next) {
|
|
if ((*n)->major == major && (*n)->probe) {
|
|
(*n)->probe(devt);
|
|
mutex_unlock(&major_names_lock);
|
|
return;
|
|
}
|
|
}
|
|
mutex_unlock(&major_names_lock);
|
|
|
|
if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
|
|
/* Make old-style 2.4 aliases work */
|
|
request_module("block-major-%d", MAJOR(devt));
|
|
}
|
|
#endif /* CONFIG_BLOCK_LEGACY_AUTOLOAD */
|
|
|
|
/*
|
|
* print a full list of all partitions - intended for places where the root
|
|
* filesystem can't be mounted and thus to give the victim some idea of what
|
|
* went wrong
|
|
*/
|
|
void __init printk_all_partitions(void)
|
|
{
|
|
struct class_dev_iter iter;
|
|
struct device *dev;
|
|
|
|
class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
|
|
while ((dev = class_dev_iter_next(&iter))) {
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
struct block_device *part;
|
|
char devt_buf[BDEVT_SIZE];
|
|
unsigned long idx;
|
|
|
|
/*
|
|
* Don't show empty devices or things that have been
|
|
* suppressed
|
|
*/
|
|
if (get_capacity(disk) == 0 || (disk->flags & GENHD_FL_HIDDEN))
|
|
continue;
|
|
|
|
/*
|
|
* Note, unlike /proc/partitions, I am showing the numbers in
|
|
* hex - the same format as the root= option takes.
|
|
*/
|
|
rcu_read_lock();
|
|
xa_for_each(&disk->part_tbl, idx, part) {
|
|
if (!bdev_nr_sectors(part))
|
|
continue;
|
|
printk("%s%s %10llu %pg %s",
|
|
bdev_is_partition(part) ? " " : "",
|
|
bdevt_str(part->bd_dev, devt_buf),
|
|
bdev_nr_sectors(part) >> 1, part,
|
|
part->bd_meta_info ?
|
|
part->bd_meta_info->uuid : "");
|
|
if (bdev_is_partition(part))
|
|
printk("\n");
|
|
else if (dev->parent && dev->parent->driver)
|
|
printk(" driver: %s\n",
|
|
dev->parent->driver->name);
|
|
else
|
|
printk(" (driver?)\n");
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
class_dev_iter_exit(&iter);
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
/* iterator */
|
|
static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
|
|
{
|
|
loff_t skip = *pos;
|
|
struct class_dev_iter *iter;
|
|
struct device *dev;
|
|
|
|
iter = kmalloc(sizeof(*iter), GFP_KERNEL);
|
|
if (!iter)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
seqf->private = iter;
|
|
class_dev_iter_init(iter, &block_class, NULL, &disk_type);
|
|
do {
|
|
dev = class_dev_iter_next(iter);
|
|
if (!dev)
|
|
return NULL;
|
|
} while (skip--);
|
|
|
|
return dev_to_disk(dev);
|
|
}
|
|
|
|
static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
|
|
{
|
|
struct device *dev;
|
|
|
|
(*pos)++;
|
|
dev = class_dev_iter_next(seqf->private);
|
|
if (dev)
|
|
return dev_to_disk(dev);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void disk_seqf_stop(struct seq_file *seqf, void *v)
|
|
{
|
|
struct class_dev_iter *iter = seqf->private;
|
|
|
|
/* stop is called even after start failed :-( */
|
|
if (iter) {
|
|
class_dev_iter_exit(iter);
|
|
kfree(iter);
|
|
seqf->private = NULL;
|
|
}
|
|
}
|
|
|
|
static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
|
|
{
|
|
void *p;
|
|
|
|
p = disk_seqf_start(seqf, pos);
|
|
if (!IS_ERR_OR_NULL(p) && !*pos)
|
|
seq_puts(seqf, "major minor #blocks name\n\n");
|
|
return p;
|
|
}
|
|
|
|
static int show_partition(struct seq_file *seqf, void *v)
|
|
{
|
|
struct gendisk *sgp = v;
|
|
struct block_device *part;
|
|
unsigned long idx;
|
|
|
|
if (!get_capacity(sgp) || (sgp->flags & GENHD_FL_HIDDEN))
|
|
return 0;
|
|
|
|
rcu_read_lock();
|
|
xa_for_each(&sgp->part_tbl, idx, part) {
|
|
if (!bdev_nr_sectors(part))
|
|
continue;
|
|
seq_printf(seqf, "%4d %7d %10llu %pg\n",
|
|
MAJOR(part->bd_dev), MINOR(part->bd_dev),
|
|
bdev_nr_sectors(part) >> 1, part);
|
|
}
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations partitions_op = {
|
|
.start = show_partition_start,
|
|
.next = disk_seqf_next,
|
|
.stop = disk_seqf_stop,
|
|
.show = show_partition
|
|
};
|
|
#endif
|
|
|
|
static int __init genhd_device_init(void)
|
|
{
|
|
int error;
|
|
|
|
error = class_register(&block_class);
|
|
if (unlikely(error))
|
|
return error;
|
|
blk_dev_init();
|
|
|
|
register_blkdev(BLOCK_EXT_MAJOR, "blkext");
|
|
|
|
/* create top-level block dir */
|
|
block_depr = kobject_create_and_add("block", NULL);
|
|
return 0;
|
|
}
|
|
|
|
subsys_initcall(genhd_device_init);
|
|
|
|
static ssize_t disk_range_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return sprintf(buf, "%d\n", disk->minors);
|
|
}
|
|
|
|
static ssize_t disk_ext_range_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return sprintf(buf, "%d\n",
|
|
(disk->flags & GENHD_FL_NO_PART) ? 1 : DISK_MAX_PARTS);
|
|
}
|
|
|
|
static ssize_t disk_removable_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return sprintf(buf, "%d\n",
|
|
(disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
|
|
}
|
|
|
|
static ssize_t disk_hidden_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return sprintf(buf, "%d\n",
|
|
(disk->flags & GENHD_FL_HIDDEN ? 1 : 0));
|
|
}
|
|
|
|
static ssize_t disk_ro_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
|
|
}
|
|
|
|
ssize_t part_size_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
return sprintf(buf, "%llu\n", bdev_nr_sectors(dev_to_bdev(dev)));
|
|
}
|
|
|
|
ssize_t part_stat_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct block_device *bdev = dev_to_bdev(dev);
|
|
struct request_queue *q = bdev_get_queue(bdev);
|
|
struct disk_stats stat;
|
|
unsigned int inflight;
|
|
|
|
if (queue_is_mq(q))
|
|
inflight = blk_mq_in_flight(q, bdev);
|
|
else
|
|
inflight = part_in_flight(bdev);
|
|
|
|
if (inflight) {
|
|
part_stat_lock();
|
|
update_io_ticks(bdev, jiffies, true);
|
|
part_stat_unlock();
|
|
}
|
|
part_stat_read_all(bdev, &stat);
|
|
return sprintf(buf,
|
|
"%8lu %8lu %8llu %8u "
|
|
"%8lu %8lu %8llu %8u "
|
|
"%8u %8u %8u "
|
|
"%8lu %8lu %8llu %8u "
|
|
"%8lu %8u"
|
|
"\n",
|
|
stat.ios[STAT_READ],
|
|
stat.merges[STAT_READ],
|
|
(unsigned long long)stat.sectors[STAT_READ],
|
|
(unsigned int)div_u64(stat.nsecs[STAT_READ], NSEC_PER_MSEC),
|
|
stat.ios[STAT_WRITE],
|
|
stat.merges[STAT_WRITE],
|
|
(unsigned long long)stat.sectors[STAT_WRITE],
|
|
(unsigned int)div_u64(stat.nsecs[STAT_WRITE], NSEC_PER_MSEC),
|
|
inflight,
|
|
jiffies_to_msecs(stat.io_ticks),
|
|
(unsigned int)div_u64(stat.nsecs[STAT_READ] +
|
|
stat.nsecs[STAT_WRITE] +
|
|
stat.nsecs[STAT_DISCARD] +
|
|
stat.nsecs[STAT_FLUSH],
|
|
NSEC_PER_MSEC),
|
|
stat.ios[STAT_DISCARD],
|
|
stat.merges[STAT_DISCARD],
|
|
(unsigned long long)stat.sectors[STAT_DISCARD],
|
|
(unsigned int)div_u64(stat.nsecs[STAT_DISCARD], NSEC_PER_MSEC),
|
|
stat.ios[STAT_FLUSH],
|
|
(unsigned int)div_u64(stat.nsecs[STAT_FLUSH], NSEC_PER_MSEC));
|
|
}
|
|
|
|
ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct block_device *bdev = dev_to_bdev(dev);
|
|
struct request_queue *q = bdev_get_queue(bdev);
|
|
unsigned int inflight[2];
|
|
|
|
if (queue_is_mq(q))
|
|
blk_mq_in_flight_rw(q, bdev, inflight);
|
|
else
|
|
part_in_flight_rw(bdev, inflight);
|
|
|
|
return sprintf(buf, "%8u %8u\n", inflight[0], inflight[1]);
|
|
}
|
|
|
|
static ssize_t disk_capability_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
dev_warn_once(dev, "the capability attribute has been deprecated.\n");
|
|
return sprintf(buf, "0\n");
|
|
}
|
|
|
|
static ssize_t disk_alignment_offset_show(struct device *dev,
|
|
struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return sprintf(buf, "%d\n", bdev_alignment_offset(disk->part0));
|
|
}
|
|
|
|
static ssize_t disk_discard_alignment_show(struct device *dev,
|
|
struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return sprintf(buf, "%d\n", bdev_alignment_offset(disk->part0));
|
|
}
|
|
|
|
static ssize_t diskseq_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return sprintf(buf, "%llu\n", disk->diskseq);
|
|
}
|
|
|
|
static DEVICE_ATTR(range, 0444, disk_range_show, NULL);
|
|
static DEVICE_ATTR(ext_range, 0444, disk_ext_range_show, NULL);
|
|
static DEVICE_ATTR(removable, 0444, disk_removable_show, NULL);
|
|
static DEVICE_ATTR(hidden, 0444, disk_hidden_show, NULL);
|
|
static DEVICE_ATTR(ro, 0444, disk_ro_show, NULL);
|
|
static DEVICE_ATTR(size, 0444, part_size_show, NULL);
|
|
static DEVICE_ATTR(alignment_offset, 0444, disk_alignment_offset_show, NULL);
|
|
static DEVICE_ATTR(discard_alignment, 0444, disk_discard_alignment_show, NULL);
|
|
static DEVICE_ATTR(capability, 0444, disk_capability_show, NULL);
|
|
static DEVICE_ATTR(stat, 0444, part_stat_show, NULL);
|
|
static DEVICE_ATTR(inflight, 0444, part_inflight_show, NULL);
|
|
static DEVICE_ATTR(badblocks, 0644, disk_badblocks_show, disk_badblocks_store);
|
|
static DEVICE_ATTR(diskseq, 0444, diskseq_show, NULL);
|
|
|
|
#ifdef CONFIG_FAIL_MAKE_REQUEST
|
|
ssize_t part_fail_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
return sprintf(buf, "%d\n", dev_to_bdev(dev)->bd_make_it_fail);
|
|
}
|
|
|
|
ssize_t part_fail_store(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
int i;
|
|
|
|
if (count > 0 && sscanf(buf, "%d", &i) > 0)
|
|
dev_to_bdev(dev)->bd_make_it_fail = i;
|
|
|
|
return count;
|
|
}
|
|
|
|
static struct device_attribute dev_attr_fail =
|
|
__ATTR(make-it-fail, 0644, part_fail_show, part_fail_store);
|
|
#endif /* CONFIG_FAIL_MAKE_REQUEST */
|
|
|
|
#ifdef CONFIG_FAIL_IO_TIMEOUT
|
|
static struct device_attribute dev_attr_fail_timeout =
|
|
__ATTR(io-timeout-fail, 0644, part_timeout_show, part_timeout_store);
|
|
#endif
|
|
|
|
static struct attribute *disk_attrs[] = {
|
|
&dev_attr_range.attr,
|
|
&dev_attr_ext_range.attr,
|
|
&dev_attr_removable.attr,
|
|
&dev_attr_hidden.attr,
|
|
&dev_attr_ro.attr,
|
|
&dev_attr_size.attr,
|
|
&dev_attr_alignment_offset.attr,
|
|
&dev_attr_discard_alignment.attr,
|
|
&dev_attr_capability.attr,
|
|
&dev_attr_stat.attr,
|
|
&dev_attr_inflight.attr,
|
|
&dev_attr_badblocks.attr,
|
|
&dev_attr_events.attr,
|
|
&dev_attr_events_async.attr,
|
|
&dev_attr_events_poll_msecs.attr,
|
|
&dev_attr_diskseq.attr,
|
|
#ifdef CONFIG_FAIL_MAKE_REQUEST
|
|
&dev_attr_fail.attr,
|
|
#endif
|
|
#ifdef CONFIG_FAIL_IO_TIMEOUT
|
|
&dev_attr_fail_timeout.attr,
|
|
#endif
|
|
NULL
|
|
};
|
|
|
|
static umode_t disk_visible(struct kobject *kobj, struct attribute *a, int n)
|
|
{
|
|
struct device *dev = container_of(kobj, typeof(*dev), kobj);
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
if (a == &dev_attr_badblocks.attr && !disk->bb)
|
|
return 0;
|
|
return a->mode;
|
|
}
|
|
|
|
static struct attribute_group disk_attr_group = {
|
|
.attrs = disk_attrs,
|
|
.is_visible = disk_visible,
|
|
};
|
|
|
|
static const struct attribute_group *disk_attr_groups[] = {
|
|
&disk_attr_group,
|
|
#ifdef CONFIG_BLK_DEV_IO_TRACE
|
|
&blk_trace_attr_group,
|
|
#endif
|
|
#ifdef CONFIG_BLK_DEV_INTEGRITY
|
|
&blk_integrity_attr_group,
|
|
#endif
|
|
NULL
|
|
};
|
|
|
|
/**
|
|
* disk_release - releases all allocated resources of the gendisk
|
|
* @dev: the device representing this disk
|
|
*
|
|
* This function releases all allocated resources of the gendisk.
|
|
*
|
|
* Drivers which used __device_add_disk() have a gendisk with a request_queue
|
|
* assigned. Since the request_queue sits on top of the gendisk for these
|
|
* drivers we also call blk_put_queue() for them, and we expect the
|
|
* request_queue refcount to reach 0 at this point, and so the request_queue
|
|
* will also be freed prior to the disk.
|
|
*
|
|
* Context: can sleep
|
|
*/
|
|
static void disk_release(struct device *dev)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
might_sleep();
|
|
WARN_ON_ONCE(disk_live(disk));
|
|
|
|
/*
|
|
* To undo the all initialization from blk_mq_init_allocated_queue in
|
|
* case of a probe failure where add_disk is never called we have to
|
|
* call blk_mq_exit_queue here. We can't do this for the more common
|
|
* teardown case (yet) as the tagset can be gone by the time the disk
|
|
* is released once it was added.
|
|
*/
|
|
if (queue_is_mq(disk->queue) &&
|
|
test_bit(GD_OWNS_QUEUE, &disk->state) &&
|
|
!test_bit(GD_ADDED, &disk->state))
|
|
blk_mq_exit_queue(disk->queue);
|
|
|
|
blkcg_exit_disk(disk);
|
|
|
|
bioset_exit(&disk->bio_split);
|
|
|
|
disk_release_events(disk);
|
|
kfree(disk->random);
|
|
disk_free_zone_bitmaps(disk);
|
|
xa_destroy(&disk->part_tbl);
|
|
|
|
disk->queue->disk = NULL;
|
|
blk_put_queue(disk->queue);
|
|
|
|
if (test_bit(GD_ADDED, &disk->state) && disk->fops->free_disk)
|
|
disk->fops->free_disk(disk);
|
|
|
|
iput(disk->part0->bd_inode); /* frees the disk */
|
|
}
|
|
|
|
static int block_uevent(const struct device *dev, struct kobj_uevent_env *env)
|
|
{
|
|
const struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
return add_uevent_var(env, "DISKSEQ=%llu", disk->diskseq);
|
|
}
|
|
|
|
struct class block_class = {
|
|
.name = "block",
|
|
.dev_uevent = block_uevent,
|
|
};
|
|
|
|
static char *block_devnode(const struct device *dev, umode_t *mode,
|
|
kuid_t *uid, kgid_t *gid)
|
|
{
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
if (disk->fops->devnode)
|
|
return disk->fops->devnode(disk, mode);
|
|
return NULL;
|
|
}
|
|
|
|
const struct device_type disk_type = {
|
|
.name = "disk",
|
|
.groups = disk_attr_groups,
|
|
.release = disk_release,
|
|
.devnode = block_devnode,
|
|
};
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
/*
|
|
* aggregate disk stat collector. Uses the same stats that the sysfs
|
|
* entries do, above, but makes them available through one seq_file.
|
|
*
|
|
* The output looks suspiciously like /proc/partitions with a bunch of
|
|
* extra fields.
|
|
*/
|
|
static int diskstats_show(struct seq_file *seqf, void *v)
|
|
{
|
|
struct gendisk *gp = v;
|
|
struct block_device *hd;
|
|
unsigned int inflight;
|
|
struct disk_stats stat;
|
|
unsigned long idx;
|
|
|
|
/*
|
|
if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
|
|
seq_puts(seqf, "major minor name"
|
|
" rio rmerge rsect ruse wio wmerge "
|
|
"wsect wuse running use aveq"
|
|
"\n\n");
|
|
*/
|
|
|
|
rcu_read_lock();
|
|
xa_for_each(&gp->part_tbl, idx, hd) {
|
|
if (bdev_is_partition(hd) && !bdev_nr_sectors(hd))
|
|
continue;
|
|
if (queue_is_mq(gp->queue))
|
|
inflight = blk_mq_in_flight(gp->queue, hd);
|
|
else
|
|
inflight = part_in_flight(hd);
|
|
|
|
if (inflight) {
|
|
part_stat_lock();
|
|
update_io_ticks(hd, jiffies, true);
|
|
part_stat_unlock();
|
|
}
|
|
part_stat_read_all(hd, &stat);
|
|
seq_printf(seqf, "%4d %7d %pg "
|
|
"%lu %lu %lu %u "
|
|
"%lu %lu %lu %u "
|
|
"%u %u %u "
|
|
"%lu %lu %lu %u "
|
|
"%lu %u"
|
|
"\n",
|
|
MAJOR(hd->bd_dev), MINOR(hd->bd_dev), hd,
|
|
stat.ios[STAT_READ],
|
|
stat.merges[STAT_READ],
|
|
stat.sectors[STAT_READ],
|
|
(unsigned int)div_u64(stat.nsecs[STAT_READ],
|
|
NSEC_PER_MSEC),
|
|
stat.ios[STAT_WRITE],
|
|
stat.merges[STAT_WRITE],
|
|
stat.sectors[STAT_WRITE],
|
|
(unsigned int)div_u64(stat.nsecs[STAT_WRITE],
|
|
NSEC_PER_MSEC),
|
|
inflight,
|
|
jiffies_to_msecs(stat.io_ticks),
|
|
(unsigned int)div_u64(stat.nsecs[STAT_READ] +
|
|
stat.nsecs[STAT_WRITE] +
|
|
stat.nsecs[STAT_DISCARD] +
|
|
stat.nsecs[STAT_FLUSH],
|
|
NSEC_PER_MSEC),
|
|
stat.ios[STAT_DISCARD],
|
|
stat.merges[STAT_DISCARD],
|
|
stat.sectors[STAT_DISCARD],
|
|
(unsigned int)div_u64(stat.nsecs[STAT_DISCARD],
|
|
NSEC_PER_MSEC),
|
|
stat.ios[STAT_FLUSH],
|
|
(unsigned int)div_u64(stat.nsecs[STAT_FLUSH],
|
|
NSEC_PER_MSEC)
|
|
);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations diskstats_op = {
|
|
.start = disk_seqf_start,
|
|
.next = disk_seqf_next,
|
|
.stop = disk_seqf_stop,
|
|
.show = diskstats_show
|
|
};
|
|
|
|
static int __init proc_genhd_init(void)
|
|
{
|
|
proc_create_seq("diskstats", 0, NULL, &diskstats_op);
|
|
proc_create_seq("partitions", 0, NULL, &partitions_op);
|
|
return 0;
|
|
}
|
|
module_init(proc_genhd_init);
|
|
#endif /* CONFIG_PROC_FS */
|
|
|
|
dev_t part_devt(struct gendisk *disk, u8 partno)
|
|
{
|
|
struct block_device *part;
|
|
dev_t devt = 0;
|
|
|
|
rcu_read_lock();
|
|
part = xa_load(&disk->part_tbl, partno);
|
|
if (part)
|
|
devt = part->bd_dev;
|
|
rcu_read_unlock();
|
|
|
|
return devt;
|
|
}
|
|
|
|
dev_t blk_lookup_devt(const char *name, int partno)
|
|
{
|
|
dev_t devt = MKDEV(0, 0);
|
|
struct class_dev_iter iter;
|
|
struct device *dev;
|
|
|
|
class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
|
|
while ((dev = class_dev_iter_next(&iter))) {
|
|
struct gendisk *disk = dev_to_disk(dev);
|
|
|
|
if (strcmp(dev_name(dev), name))
|
|
continue;
|
|
|
|
if (partno < disk->minors) {
|
|
/* We need to return the right devno, even
|
|
* if the partition doesn't exist yet.
|
|
*/
|
|
devt = MKDEV(MAJOR(dev->devt),
|
|
MINOR(dev->devt) + partno);
|
|
} else {
|
|
devt = part_devt(disk, partno);
|
|
if (devt)
|
|
break;
|
|
}
|
|
}
|
|
class_dev_iter_exit(&iter);
|
|
return devt;
|
|
}
|
|
|
|
struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
|
|
struct lock_class_key *lkclass)
|
|
{
|
|
struct gendisk *disk;
|
|
|
|
disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
|
|
if (!disk)
|
|
return NULL;
|
|
|
|
if (bioset_init(&disk->bio_split, BIO_POOL_SIZE, 0, 0))
|
|
goto out_free_disk;
|
|
|
|
disk->bdi = bdi_alloc(node_id);
|
|
if (!disk->bdi)
|
|
goto out_free_bioset;
|
|
|
|
/* bdev_alloc() might need the queue, set before the first call */
|
|
disk->queue = q;
|
|
|
|
disk->part0 = bdev_alloc(disk, 0);
|
|
if (!disk->part0)
|
|
goto out_free_bdi;
|
|
|
|
disk->node_id = node_id;
|
|
mutex_init(&disk->open_mutex);
|
|
xa_init(&disk->part_tbl);
|
|
if (xa_insert(&disk->part_tbl, 0, disk->part0, GFP_KERNEL))
|
|
goto out_destroy_part_tbl;
|
|
|
|
if (blkcg_init_disk(disk))
|
|
goto out_erase_part0;
|
|
|
|
rand_initialize_disk(disk);
|
|
disk_to_dev(disk)->class = &block_class;
|
|
disk_to_dev(disk)->type = &disk_type;
|
|
device_initialize(disk_to_dev(disk));
|
|
inc_diskseq(disk);
|
|
q->disk = disk;
|
|
lockdep_init_map(&disk->lockdep_map, "(bio completion)", lkclass, 0);
|
|
#ifdef CONFIG_BLOCK_HOLDER_DEPRECATED
|
|
INIT_LIST_HEAD(&disk->slave_bdevs);
|
|
#endif
|
|
return disk;
|
|
|
|
out_erase_part0:
|
|
xa_erase(&disk->part_tbl, 0);
|
|
out_destroy_part_tbl:
|
|
xa_destroy(&disk->part_tbl);
|
|
disk->part0->bd_disk = NULL;
|
|
iput(disk->part0->bd_inode);
|
|
out_free_bdi:
|
|
bdi_put(disk->bdi);
|
|
out_free_bioset:
|
|
bioset_exit(&disk->bio_split);
|
|
out_free_disk:
|
|
kfree(disk);
|
|
return NULL;
|
|
}
|
|
|
|
struct gendisk *__blk_alloc_disk(int node, struct lock_class_key *lkclass)
|
|
{
|
|
struct request_queue *q;
|
|
struct gendisk *disk;
|
|
|
|
q = blk_alloc_queue(node);
|
|
if (!q)
|
|
return NULL;
|
|
|
|
disk = __alloc_disk_node(q, node, lkclass);
|
|
if (!disk) {
|
|
blk_put_queue(q);
|
|
return NULL;
|
|
}
|
|
set_bit(GD_OWNS_QUEUE, &disk->state);
|
|
return disk;
|
|
}
|
|
EXPORT_SYMBOL(__blk_alloc_disk);
|
|
|
|
/**
|
|
* put_disk - decrements the gendisk refcount
|
|
* @disk: the struct gendisk to decrement the refcount for
|
|
*
|
|
* This decrements the refcount for the struct gendisk. When this reaches 0
|
|
* we'll have disk_release() called.
|
|
*
|
|
* Note: for blk-mq disk put_disk must be called before freeing the tag_set
|
|
* when handling probe errors (that is before add_disk() is called).
|
|
*
|
|
* Context: Any context, but the last reference must not be dropped from
|
|
* atomic context.
|
|
*/
|
|
void put_disk(struct gendisk *disk)
|
|
{
|
|
if (disk)
|
|
put_device(disk_to_dev(disk));
|
|
}
|
|
EXPORT_SYMBOL(put_disk);
|
|
|
|
static void set_disk_ro_uevent(struct gendisk *gd, int ro)
|
|
{
|
|
char event[] = "DISK_RO=1";
|
|
char *envp[] = { event, NULL };
|
|
|
|
if (!ro)
|
|
event[8] = '0';
|
|
kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
|
|
}
|
|
|
|
/**
|
|
* set_disk_ro - set a gendisk read-only
|
|
* @disk: gendisk to operate on
|
|
* @read_only: %true to set the disk read-only, %false set the disk read/write
|
|
*
|
|
* This function is used to indicate whether a given disk device should have its
|
|
* read-only flag set. set_disk_ro() is typically used by device drivers to
|
|
* indicate whether the underlying physical device is write-protected.
|
|
*/
|
|
void set_disk_ro(struct gendisk *disk, bool read_only)
|
|
{
|
|
if (read_only) {
|
|
if (test_and_set_bit(GD_READ_ONLY, &disk->state))
|
|
return;
|
|
} else {
|
|
if (!test_and_clear_bit(GD_READ_ONLY, &disk->state))
|
|
return;
|
|
}
|
|
set_disk_ro_uevent(disk, read_only);
|
|
}
|
|
EXPORT_SYMBOL(set_disk_ro);
|
|
|
|
void inc_diskseq(struct gendisk *disk)
|
|
{
|
|
disk->diskseq = atomic64_inc_return(&diskseq);
|
|
}
|