/*
 * Copyright 2014  Google, Inc.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include "internal.h"

static DEFINE_MUTEX(pmsg_lock);

static ssize_t write_pmsg(struct file *file, const char __user *buf,
			  size_t count, loff_t *ppos)
{
	u64 id;
	int ret;

	if (!count)
		return 0;

	/* check outside lock, page in any data. write_buf_user also checks */
	if (!access_ok(VERIFY_READ, buf, count))
		return -EFAULT;

	mutex_lock(&pmsg_lock);
	ret = psinfo->write_buf_user(PSTORE_TYPE_PMSG, 0, &id, 0, buf, 0, count,
				     psinfo);
	mutex_unlock(&pmsg_lock);
	return ret ? ret : count;
}

static const struct file_operations pmsg_fops = {
	.owner		= THIS_MODULE,
	.llseek		= noop_llseek,
	.write		= write_pmsg,
};

static struct class *pmsg_class;
static int pmsg_major;
#define PMSG_NAME "pmsg"
#undef pr_fmt
#define pr_fmt(fmt) PMSG_NAME ": " fmt

static char *pmsg_devnode(struct device *dev, umode_t *mode)
{
	if (mode)
		*mode = 0220;
	return NULL;
}

void pstore_register_pmsg(void)
{
	struct device *pmsg_device;

	pmsg_major = register_chrdev(0, PMSG_NAME, &pmsg_fops);
	if (pmsg_major < 0) {
		pr_err("register_chrdev failed\n");
		goto err;
	}

	pmsg_class = class_create(THIS_MODULE, PMSG_NAME);
	if (IS_ERR(pmsg_class)) {
		pr_err("device class file already in use\n");
		goto err_class;
	}
	pmsg_class->devnode = pmsg_devnode;

	pmsg_device = device_create(pmsg_class, NULL, MKDEV(pmsg_major, 0),
					NULL, "%s%d", PMSG_NAME, 0);
	if (IS_ERR(pmsg_device)) {
		pr_err("failed to create device\n");
		goto err_device;
	}
	return;

err_device:
	class_destroy(pmsg_class);
err_class:
	unregister_chrdev(pmsg_major, PMSG_NAME);
err:
	return;
}

void pstore_unregister_pmsg(void)
{
	device_destroy(pmsg_class, MKDEV(pmsg_major, 0));
	class_destroy(pmsg_class);
	unregister_chrdev(pmsg_major, PMSG_NAME);
}
value='9a9a7a572709487acb0d2de83b375e8fbb4f9d91'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/log/?h=nds-private-remove&amp;id=9a9a7a572709487acb0d2de83b375e8fbb4f9d91'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/net?h=nds-private-remove&amp;id=9a9a7a572709487acb0d2de83b375e8fbb4f9d91'>net</a>/<a href='/cgit.cgi/linux/net-next.git/log/net/l2tp?h=nds-private-remove&amp;id=9a9a7a572709487acb0d2de83b375e8fbb4f9d91'>l2tp</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/net/l2tp?h=nds-private-remove&amp;id=9a9a7a572709487acb0d2de83b375e8fbb4f9d91&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
<tr><td><span title='2017-02-07 13:07:47 -0500'>2017-02-07</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net/l2tp?h=nds-private-remove&amp;id=0dec879f636f11b0ffda1cb5fd96a1754c59ead3'>net: use dst_confirm_neigh for UDP, RAW, ICMP, L2TP</a></td><td>Julian Anastasov</td><td>1</td><td><span class='deletions'>-1</span>/<span class='insertions'>+2</span></td></tr>