Contributors: 36
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Linus Torvalds (pre-git) |
364 |
34.31% |
30 |
37.04% |
| Stephen Hemminger |
220 |
20.74% |
3 |
3.70% |
| D Scott Phillips |
114 |
10.74% |
1 |
1.23% |
| Kay Sievers |
60 |
5.66% |
2 |
2.47% |
| Greg Kroah-Hartman |
59 |
5.56% |
9 |
11.11% |
| Denis V. Lunev |
38 |
3.58% |
1 |
1.23% |
| Matthias Kaehlcke |
25 |
2.36% |
1 |
1.23% |
| Jakob Koschel |
23 |
2.17% |
1 |
1.23% |
| Vladimir Zapolskiy |
19 |
1.79% |
1 |
1.23% |
| Dae S. Kim |
17 |
1.60% |
1 |
1.23% |
| Thadeu Lima de Souza Cascardo |
13 |
1.23% |
2 |
2.47% |
| Pavel Emelyanov |
12 |
1.13% |
1 |
1.23% |
| Elad Wexler |
12 |
1.13% |
1 |
1.23% |
| Andrew Morton |
11 |
1.04% |
2 |
2.47% |
| Sudip Mukherjee |
11 |
1.04% |
1 |
1.23% |
| Al Viro |
6 |
0.57% |
3 |
3.70% |
| Maksim Krasnyanskiy |
6 |
0.57% |
1 |
1.23% |
| Samu Onkalo |
6 |
0.57% |
1 |
1.23% |
| Robert Love |
6 |
0.57% |
1 |
1.23% |
| Takashi Iwai |
5 |
0.47% |
1 |
1.23% |
| Arnd Bergmann |
5 |
0.47% |
1 |
1.23% |
| Art Haas |
4 |
0.38% |
1 |
1.23% |
| Chris Wright |
4 |
0.38% |
1 |
1.23% |
| Akinobu Mita |
3 |
0.28% |
1 |
1.23% |
| Avi Kivity |
3 |
0.28% |
1 |
1.23% |
| Christoph Hellwig |
2 |
0.19% |
1 |
1.23% |
| Rafael J. Wysocki |
2 |
0.19% |
1 |
1.23% |
| Arjan van de Ven |
2 |
0.19% |
2 |
2.47% |
| Mikael Pettersson |
2 |
0.19% |
1 |
1.23% |
| Varsha Rao |
1 |
0.09% |
1 |
1.23% |
| James Morris |
1 |
0.09% |
1 |
1.23% |
| Neil Horman |
1 |
0.09% |
1 |
1.23% |
| Tom Van Braeckel |
1 |
0.09% |
1 |
1.23% |
| Tal Shorer |
1 |
0.09% |
1 |
1.23% |
| Sangmoon Kim |
1 |
0.09% |
1 |
1.23% |
| Linus Torvalds |
1 |
0.09% |
1 |
1.23% |
| Total |
1061 |
|
81 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* linux/drivers/char/misc.c
*
* Generic misc open routine by Johan Myreen
*
* Based on code from Linus
*
* Teemu Rantanen's Microsoft Busmouse support and Derrick Cole's
* changes incorporated into 0.97pl4
* by Peter Cervasio (pete%q106fm.uucp@wupost.wustl.edu) (08SEP92)
* See busmouse.c for particulars.
*
* Made things a lot mode modular - easy to compile in just one or two
* of the misc drivers, as they are now completely independent. Linus.
*
* Support for loadable modules. 8-Sep-95 Philip Blundell <pjb27@cam.ac.uk>
*
* Fixed a failing symbol register to free the device registration
* Alan Cox <alan@lxorguk.ukuu.org.uk> 21-Jan-96
*
* Dynamic minors and /proc/mice by Alessandro Rubini. 26-Mar-96
*
* Renamed to misc and miscdevice to be more accurate. Alan Cox 26-Mar-96
*
* Handling of mouse minor numbers for kerneld:
* Idea by Jacques Gelinas <jack@solucorp.qc.ca>,
* adapted by Bjorn Ekwall <bj0rn@blox.se>
* corrected by Alan Cox <alan@lxorguk.ukuu.org.uk>
*
* Changes for kmod (from kerneld):
* Cyrus Durgin <cider@speakeasy.org>
*
* Added devfs support. Richard Gooch <rgooch@atnf.csiro.au> 10-Jan-1998
*/
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/mutex.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/tty.h>
#include <linux/kmod.h>
#include <linux/gfp.h>
/*
* Head entry for the doubly linked miscdevice list
*/
static LIST_HEAD(misc_list);
static DEFINE_MUTEX(misc_mtx);
/*
* Assigned numbers, used for dynamic minors
*/
#define DYNAMIC_MINORS 128 /* like dynamic majors */
static DEFINE_IDA(misc_minors_ida);
static int misc_minor_alloc(void)
{
int ret;
ret = ida_alloc_max(&misc_minors_ida, DYNAMIC_MINORS - 1, GFP_KERNEL);
if (ret >= 0) {
ret = DYNAMIC_MINORS - ret - 1;
} else {
ret = ida_alloc_range(&misc_minors_ida, MISC_DYNAMIC_MINOR + 1,
MINORMASK, GFP_KERNEL);
}
return ret;
}
static void misc_minor_free(int minor)
{
if (minor < DYNAMIC_MINORS)
ida_free(&misc_minors_ida, DYNAMIC_MINORS - minor - 1);
else if (minor > MISC_DYNAMIC_MINOR)
ida_free(&misc_minors_ida, minor);
}
#ifdef CONFIG_PROC_FS
static void *misc_seq_start(struct seq_file *seq, loff_t *pos)
{
mutex_lock(&misc_mtx);
return seq_list_start(&misc_list, *pos);
}
static void *misc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
return seq_list_next(v, &misc_list, pos);
}
static void misc_seq_stop(struct seq_file *seq, void *v)
{
mutex_unlock(&misc_mtx);
}
static int misc_seq_show(struct seq_file *seq, void *v)
{
const struct miscdevice *p = list_entry(v, struct miscdevice, list);
seq_printf(seq, "%3i %s\n", p->minor, p->name ? p->name : "");
return 0;
}
static const struct seq_operations misc_seq_ops = {
.start = misc_seq_start,
.next = misc_seq_next,
.stop = misc_seq_stop,
.show = misc_seq_show,
};
#endif
static int misc_open(struct inode *inode, struct file *file)
{
int minor = iminor(inode);
struct miscdevice *c = NULL, *iter;
int err = -ENODEV;
const struct file_operations *new_fops = NULL;
mutex_lock(&misc_mtx);
list_for_each_entry(iter, &misc_list, list) {
if (iter->minor != minor)
continue;
c = iter;
new_fops = fops_get(iter->fops);
break;
}
if (!new_fops) {
mutex_unlock(&misc_mtx);
request_module("char-major-%d-%d", MISC_MAJOR, minor);
mutex_lock(&misc_mtx);
list_for_each_entry(iter, &misc_list, list) {
if (iter->minor != minor)
continue;
c = iter;
new_fops = fops_get(iter->fops);
break;
}
if (!new_fops)
goto fail;
}
/*
* Place the miscdevice in the file's
* private_data so it can be used by the
* file operations, including f_op->open below
*/
file->private_data = c;
err = 0;
replace_fops(file, new_fops);
if (file->f_op->open)
err = file->f_op->open(inode, file);
fail:
mutex_unlock(&misc_mtx);
return err;
}
static struct class *misc_class;
static const struct file_operations misc_fops = {
.owner = THIS_MODULE,
.open = misc_open,
.llseek = noop_llseek,
};
/**
* misc_register - register a miscellaneous device
* @misc: device structure
*
* Register a miscellaneous device with the kernel. If the minor
* number is set to %MISC_DYNAMIC_MINOR a minor number is assigned
* and placed in the minor field of the structure. For other cases
* the minor number requested is used.
*
* The structure passed is linked into the kernel and may not be
* destroyed until it has been unregistered. By default, an open()
* syscall to the device sets file->private_data to point to the
* structure. Drivers don't need open in fops for this.
*
* A zero is returned on success and a negative errno code for
* failure.
*/
int misc_register(struct miscdevice *misc)
{
dev_t dev;
int err = 0;
bool is_dynamic = (misc->minor == MISC_DYNAMIC_MINOR);
INIT_LIST_HEAD(&misc->list);
mutex_lock(&misc_mtx);
if (is_dynamic) {
int i = misc_minor_alloc();
if (i < 0) {
err = -EBUSY;
goto out;
}
misc->minor = i;
} else {
struct miscdevice *c;
list_for_each_entry(c, &misc_list, list) {
if (c->minor == misc->minor) {
err = -EBUSY;
goto out;
}
}
}
dev = MKDEV(MISC_MAJOR, misc->minor);
misc->this_device =
device_create_with_groups(misc_class, misc->parent, dev,
misc, misc->groups, "%s", misc->name);
if (IS_ERR(misc->this_device)) {
if (is_dynamic) {
misc_minor_free(misc->minor);
misc->minor = MISC_DYNAMIC_MINOR;
}
err = PTR_ERR(misc->this_device);
goto out;
}
/*
* Add it to the front, so that later devices can "override"
* earlier defaults
*/
list_add(&misc->list, &misc_list);
out:
mutex_unlock(&misc_mtx);
return err;
}
EXPORT_SYMBOL(misc_register);
/**
* misc_deregister - unregister a miscellaneous device
* @misc: device to unregister
*
* Unregister a miscellaneous device that was previously
* successfully registered with misc_register().
*/
void misc_deregister(struct miscdevice *misc)
{
if (WARN_ON(list_empty(&misc->list)))
return;
mutex_lock(&misc_mtx);
list_del(&misc->list);
device_destroy(misc_class, MKDEV(MISC_MAJOR, misc->minor));
misc_minor_free(misc->minor);
mutex_unlock(&misc_mtx);
}
EXPORT_SYMBOL(misc_deregister);
static char *misc_devnode(const struct device *dev, umode_t *mode)
{
const struct miscdevice *c = dev_get_drvdata(dev);
if (mode && c->mode)
*mode = c->mode;
if (c->nodename)
return kstrdup(c->nodename, GFP_KERNEL);
return NULL;
}
static int __init misc_init(void)
{
int err;
struct proc_dir_entry *ret;
ret = proc_create_seq("misc", 0, NULL, &misc_seq_ops);
misc_class = class_create(THIS_MODULE, "misc");
err = PTR_ERR(misc_class);
if (IS_ERR(misc_class))
goto fail_remove;
err = -EIO;
if (register_chrdev(MISC_MAJOR, "misc", &misc_fops))
goto fail_printk;
misc_class->devnode = misc_devnode;
return 0;
fail_printk:
pr_err("unable to get major %d for misc devices\n", MISC_MAJOR);
class_destroy(misc_class);
fail_remove:
if (ret)
remove_proc_entry("misc", NULL);
return err;
}
subsys_initcall(misc_init);