/*
 *  net/9p/util.c
 *
 *  This file contains some helper functions
 *
 *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
 *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to:
 *  Free Software Foundation
 *  51 Franklin Street, Fifth Floor
 *  Boston, MA  02111-1301  USA
 *
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/parser.h>
#include <linux/idr.h>
#include <linux/slab.h>
#include <net/9p/9p.h>

/**
 * struct p9_idpool - per-connection accounting for tag idpool
 * @lock: protects the pool
 * @pool: idr to allocate tag id from
 *
 */

struct p9_idpool {
	spinlock_t lock;
	struct idr pool;
};

/**
 * p9_idpool_create - create a new per-connection id pool
 *
 */

struct p9_idpool *p9_idpool_create(void)
{
	struct p9_idpool *p;

	p = kmalloc(sizeof(struct p9_idpool), GFP_KERNEL);
	if (!p)
		return ERR_PTR(-ENOMEM);

	spin_lock_init(&p->lock);
	idr_init(&p->pool);

	return p;
}
EXPORT_SYMBOL(p9_idpool_create);

/**
 * p9_idpool_destroy - create a new per-connection id pool
 * @p: idpool to destroy
 */

void p9_idpool_destroy(struct p9_idpool *p)
{
	idr_destroy(&p->pool);
	kfree(p);
}
EXPORT_SYMBOL(p9_idpool_destroy);

/**
 * p9_idpool_get - allocate numeric id from pool
 * @p: pool to allocate from
 *
 * Bugs: This seems to be an awful generic function, should it be in idr.c with
 *            the lock included in struct idr?
 */

int p9_idpool_get(struct p9_idpool *p)
{
	int i;
	unsigned long flags;

	idr_preload(GFP_NOFS);
	spin_lock_irqsave(&p->lock, flags);

	/* no need to store exactly p, we just need something non-null */
	i = idr_alloc(&p->pool, p, 0, 0, GFP_NOWAIT);

	spin_unlock_irqrestore(&p->lock, flags);
	idr_preload_end();
	if (i < 0)
		return -1;

	p9_debug(P9_DEBUG_MUX, " id %d pool %p\n", i, p);
	return i;
}
EXPORT_SYMBOL(p9_idpool_get);

/**
 * p9_idpool_put - release numeric id from pool
 * @id: numeric id which is being released
 * @p: pool to release id into
 *
 * Bugs: This seems to be an awful generic function, should it be in idr.c with
 *            the lock included in struct idr?
 */

void p9_idpool_put(int id, struct p9_idpool *p)
{
	unsigned long flags;

	p9_debug(P9_DEBUG_MUX, " id %d pool %p\n", id, p);

	spin_lock_irqsave(&p->lock, flags);
	idr_remove(&p->pool, id);
	spin_unlock_irqrestore(&p->lock, flags);
}
EXPORT_SYMBOL(p9_idpool_put);

/**
 * p9_idpool_check - check if the specified id is available
 * @id: id to check
 * @p: pool to check
 */

int p9_idpool_check(int id, struct p9_idpool *p)
{
	return idr_find(&p->pool, id) != NULL;
}
EXPORT_SYMBOL(p9_idpool_check);

ion value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-28 15:09:23 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-28 15:09:23 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=53cd1ad1a68fd10f677445e04ed63aa9ce39b36b'>53cd1ad1a68fd10f677445e04ed63aa9ce39b36b</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=53cd1ad1a68fd10f677445e04ed63aa9ce39b36b'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=53cd1ad1a68fd10f677445e04ed63aa9ce39b36b'>c3401d2cbce4615b9a4e1d2bc060e8a310321eaa</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=d56a5ca366e785f463b4782f65daac883612a2b2'>d56a5ca366e785f463b4782f65daac883612a2b2</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?id=53cd1ad1a68fd10f677445e04ed63aa9ce39b36b&amp;id2=d56a5ca366e785f463b4782f65daac883612a2b2'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=e13fe92bb58cf9b8f709ec18267ffc9e6ffeb016'>e13fe92bb58cf9b8f709ec18267ffc9e6ffeb016</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?id=53cd1ad1a68fd10f677445e04ed63aa9ce39b36b&amp;id2=e13fe92bb58cf9b8f709ec18267ffc9e6ffeb016'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux</div><div class='commit-msg'>Pull i2c fixes from Wolfram Sang:
 "Two I2C driver bugfixes.

  The 'VLLS mode support' patch should have been entitled 'reconfigure
  pinctrl after suspend' to make the bugfix more clear. Sorry, I missed
  that, yet didn't want to rebase"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: imx-lpi2c: add VLLS mode support
  i2c: i2c-cadence: Initialize configuration before probing devices
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=53cd1ad1a68fd10f677445e04ed63aa9ce39b36b'>Diffstat</a></div><table summary='diffstat' class='diffstat'>