/*
 * Common code for control of lockd and nfsv4 grace periods.
 *
 * Transplanted from lockd code
 */

#include <linux/module.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <linux/fs.h>

static unsigned int grace_net_id;
static DEFINE_SPINLOCK(grace_lock);

/**
 * locks_start_grace
 * @net: net namespace that this lock manager belongs to
 * @lm: who this grace period is for
 *
 * A grace period is a period during which locks should not be given
 * out.  Currently grace periods are only enforced by the two lock
 * managers (lockd and nfsd), using the locks_in_grace() function to
 * check when they are in a grace period.
 *
 * This function is called to start a grace period.
 */
void
locks_start_grace(struct net *net, struct lock_manager *lm)
{
	struct list_head *grace_list = net_generic(net, grace_net_id);

	spin_lock(&grace_lock);
	list_add(&lm->list, grace_list);
	spin_unlock(&grace_lock);
}
EXPORT_SYMBOL_GPL(locks_start_grace);

/**
 * locks_end_grace
 * @net: net namespace that this lock manager belongs to
 * @lm: who this grace period is for
 *
 * Call this function to state that the given lock manager is ready to
 * resume regular locking.  The grace period will not end until all lock
 * managers that called locks_start_grace() also call locks_end_grace().
 * Note that callers count on it being safe to call this more than once,
 * and the second call should be a no-op.
 */
void
locks_end_grace(struct lock_manager *lm)
{
	spin_lock(&grace_lock);
	list_del_init(&lm->list);
	spin_unlock(&grace_lock);
}
EXPORT_SYMBOL_GPL(locks_end_grace);

/**
 * locks_in_grace
 *
 * Lock managers call this function to determine when it is OK for them
 * to answer ordinary lock requests, and when they should accept only
 * lock reclaims.
 */
int
__state_in_grace(struct net *net, bool open)
{
	struct list_head *grace_list = net_generic(net, grace_net_id);
	struct lock_manager *lm;

	if (!open)
		return !list_empty(grace_list);

	list_for_each_entry(lm, grace_list, list) {
		if (lm->block_opens)
			return true;
	}
	return false;
}

int locks_in_grace(struct net *net)
{
	return __state_in_grace(net, 0);
}
EXPORT_SYMBOL_GPL(locks_in_grace);

int opens_in_grace(struct net *net)
{
	return __state_in_grace(net, 1);
}
EXPORT_SYMBOL_GPL(opens_in_grace);

static int __net_init
grace_init_net(struct net *net)
{
	struct list_head *grace_list = net_generic(net, grace_net_id);

	INIT_LIST_HEAD(grace_list);
	return 0;
}

static void __net_exit
grace_exit_net(struct net *net)
{
	struct list_head *grace_list = net_generic(net, grace_net_id);

	BUG_ON(!list_empty(grace_list));
}

static struct pernet_operations grace_net_ops = {
	.init = grace_init_net,
	.exit = grace_exit_net,
	.id   = &grace_net_id,
	.size = sizeof(struct list_head),
};

static int __init
init_grace(void)
{
	return register_pernet_subsys(&grace_net_ops);
}

static void __exit
exit_grace(void)
{
	unregister_pernet_subsys(&grace_net_ops);
}

MODULE_AUTHOR("Jeff Layton <jlayton@primarydata.com>");
MODULE_LICENSE("GPL");
module_init(init_grace)
module_exit(exit_grace)
8505e95a1863'>dt-bindings</a>/<a href='/cgit.cgi/linux/net-next.git/log/include/dt-bindings/pinctrl?id=aa8863e5d49417094b9457a0d53e8505e95a1863'>pinctrl</a>/<a href='/cgit.cgi/linux/net-next.git/log/include/dt-bindings/pinctrl/stm32f429-pinfunc.h?id=aa8863e5d49417094b9457a0d53e8505e95a1863'>stm32f429-pinfunc.h</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/include/dt-bindings/pinctrl/stm32f429-pinfunc.h?id=aa8863e5d49417094b9457a0d53e8505e95a1863&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
t.git/commit/net/ipv6?h=nds-private-remove&amp;id=97e219b7c1f75b14b29abe28ad53e8709e8d15e5'>gro_cells: move to net/core/gro_cells.c</a></td><td>Eric Dumazet</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+1</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
We have many gro cells users, so lets move the code to avoid
duplication.

This creates a CONFIG_GRO_CELLS option.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-07 16:29:30 -0500'>2017-02-07</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/net/ipv6?h=nds-private-remove&amp;id=3efa70d78f218e4c9276b0bac0545e5184c1c47b'>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</a></td><td>David S. Miller