[net-next-2.6.git] / fs / lockd / svc.c

/*
 * linux/fs/lockd/svc.c
 *
 * This is the central lockd service.
 *
 * FIXME: Separate the lockd NFS server functionality from the lockd NFS
 * 	  client functionality. Oh why didn't Sun create two separate
 *	  services in the first place?
 *
 * Authors:	Olaf Kirch (okir@monad.swb.de)
 *
 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/sysctl.h>
#include <linux/moduleparam.h>

#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/in.h>
#include <linux/uio.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/mutex.h>
#include <linux/kthread.h>
#include <linux/freezer.h>

#include <linux/sunrpc/types.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/svcsock.h>
#include <net/ip.h>
#include <linux/lockd/lockd.h>
#include <linux/lockd/sm_inter.h>
#include <linux/nfs.h>

#define NLMDBG_FACILITY		NLMDBG_SVC
#define LOCKD_BUFSIZE		(1024 + NLMSVC_XDRSIZE)
#define ALLOWED_SIGS		(sigmask(SIGKILL))

static struct svc_program	nlmsvc_program;

struct nlmsvc_binding *		nlmsvc_ops;
EXPORT_SYMBOL(nlmsvc_ops);

static DEFINE_MUTEX(nlmsvc_mutex);
static unsigned int		nlmsvc_users;
static struct task_struct	*nlmsvc_task;
static struct svc_serv		*nlmsvc_serv;
int				nlmsvc_grace_period;
unsigned long			nlmsvc_timeout;

/*
 * These can be set at insmod time (useful for NFS as root filesystem),
 * and also changed through the sysctl interface.  -- Jamie Lokier, Aug 2003
 */
static unsigned long		nlm_grace_period;
static unsigned long		nlm_timeout = LOCKD_DFLT_TIMEO;
static int			nlm_udpport, nlm_tcpport;
int				nsm_use_hostnames = 0;

/*
 * Constants needed for the sysctl interface.
 */
static const unsigned long	nlm_grace_period_min = 0;
static const unsigned long	nlm_grace_period_max = 240;
static const unsigned long	nlm_timeout_min = 3;
static const unsigned long	nlm_timeout_max = 20;
static const int		nlm_port_min = 0, nlm_port_max = 65535;

#ifdef CONFIG_SYSCTL
static struct ctl_table_header * nlm_sysctl_table;
#endif

static unsigned long get_lockd_grace_period(void)
{
	/* Note: nlm_timeout should always be nonzero */
	if (nlm_grace_period)
		return roundup(nlm_grace_period, nlm_timeout) * HZ;
	else
		return nlm_timeout * 5 * HZ;
}

unsigned long get_nfs_grace_period(void)
{
	unsigned long lockdgrace = get_lockd_grace_period();
	unsigned long nfsdgrace = 0;

	if (nlmsvc_ops)
		nfsdgrace = nlmsvc_ops->get_grace_period();

	return max(lockdgrace, nfsdgrace);
}
EXPORT_SYMBOL(get_nfs_grace_period);

static unsigned long set_grace_period(void)
{
	nlmsvc_grace_period = 1;
	return get_nfs_grace_period() + jiffies;
}

static inline void clear_grace_period(void)
{
	nlmsvc_grace_period = 0;
}

/*
 * This is the lockd kernel thread
 */
static int
lockd(void *vrqstp)
{
	int		err = 0, preverr = 0;
	struct svc_rqst *rqstp = vrqstp;
	unsigned long grace_period_expire;

	/* try_to_freeze() is called from svc_recv() */
	set_freezable();

	/* Allow SIGKILL to tell lockd to drop all of its locks */
	allow_signal(SIGKILL);

	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");

	/*
	 * FIXME: it would be nice if lockd didn't spend its entire life
	 * running under the BKL. At the very least, it would be good to
	 * have someone clarify what it's intended to protect here. I've
	 * seen some handwavy posts about posix locking needing to be
	 * done under the BKL, but it's far from clear.
	 */
	lock_kernel();

	if (!nlm_timeout)
		nlm_timeout = LOCKD_DFLT_TIMEO;
	nlmsvc_timeout = nlm_timeout * HZ;

	grace_period_expire = set_grace_period();

	/*
	 * The main request loop. We don't terminate until the last
	 * NFS mount or NFS daemon has gone away.
	 */
	while (!kthread_should_stop()) {
		long timeout = MAX_SCHEDULE_TIMEOUT;
		RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);

		if (signalled()) {
			flush_signals(current);
			if (nlmsvc_ops) {
				nlmsvc_invalidate_all();
				grace_period_expire = set_grace_period();
			}
			continue;
		}

		/*
		 * Retry any blocked locks that have been notified by
		 * the VFS. Don't do this during grace period.
		 * (Theoretically, there shouldn't even be blocked locks
		 * during grace period).
		 */
		if (!nlmsvc_grace_period) {
			timeout = nlmsvc_retry_blocked();
		} else if (time_before(grace_period_expire, jiffies))
			clear_grace_period();

		/*
		 * Find a socket with data available and call its
		 * recvfrom routine.
		 */
		err = svc_recv(rqstp, timeout);
		if (err == -EAGAIN || err == -EINTR) {
			preverr = err;
			continue;
		}
		if (err < 0) {
			if (err != preverr) {
				printk(KERN_WARNING "%s: unexpected error "
					"from svc_recv (%d)\n", __func__, err);
				preverr = err;
			}
			schedule_timeout_interruptible(HZ);
			continue;
		}
		preverr = err;

		dprintk("lockd: request from %s\n",
				svc_print_addr(rqstp, buf, sizeof(buf)));

		svc_process(rqstp);
	}

	flush_signals(current);
	if (nlmsvc_ops)
		nlmsvc_invalidate_all();
	nlm_shutdown_hosts();

	unlock_kernel();

	nlmsvc_task = NULL;
	nlmsvc_serv = NULL;

	/* Exit the RPC thread */
	svc_exit_thread(rqstp);

	return 0;
}

/*
 * Make any sockets that are needed but not present.
 * If nlm_udpport or nlm_tcpport were set as module
 * options, make those sockets unconditionally
 */
static int make_socks(struct svc_serv *serv, int proto)
{
	static int warned;
	struct svc_xprt *xprt;
	int err = 0;

	if (proto == IPPROTO_UDP || nlm_udpport) {
		xprt = svc_find_xprt(serv, "udp", 0, 0);
		if (!xprt)
			err = svc_create_xprt(serv, "udp", nlm_udpport,
					      SVC_SOCK_DEFAULTS);
		else
			svc_xprt_put(xprt);
	}
	if (err >= 0 && (proto == IPPROTO_TCP || nlm_tcpport)) {
		xprt = svc_find_xprt(serv, "tcp", 0, 0);
		if (!xprt)
			err = svc_create_xprt(serv, "tcp", nlm_tcpport,
					      SVC_SOCK_DEFAULTS);
		else
			svc_xprt_put(xprt);
	}
	if (err >= 0) {
		warned = 0;
		err = 0;
	} else if (warned++ == 0)
		printk(KERN_WARNING
		       "lockd_up: makesock failed, error=%d\n", err);
	return err;
}

/*
 * Bring up the lockd process if it's not already up.
 */
int
lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */
{
	struct svc_serv *serv;
	struct svc_rqst *rqstp;
	int		error = 0;

	mutex_lock(&nlmsvc_mutex);
	/*
	 * Check whether we're already up and running.
	 */
	if (nlmsvc_serv) {
		if (proto)
			error = make_socks(nlmsvc_serv, proto);
		goto out;
	}

	/*
	 * Sanity check: if there's no pid,
	 * we should be the first user ...
	 */
	if (nlmsvc_users)
		printk(KERN_WARNING
			"lockd_up: no pid, %d users??\n", nlmsvc_users);

	error = -ENOMEM;
	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
	if (!serv) {
		printk(KERN_WARNING "lockd_up: create service failed\n");
		goto out;
	}

	if ((error = make_socks(serv, proto)) < 0)
		goto destroy_and_out;

	/*
	 * Create the kernel thread and wait for it to start.
	 */
	rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]);
	if (IS_ERR(rqstp)) {
		error = PTR_ERR(rqstp);
		printk(KERN_WARNING
			"lockd_up: svc_rqst allocation failed, error=%d\n",
			error);
		goto destroy_and_out;
	}

	svc_sock_update_bufs(serv);
	nlmsvc_serv = rqstp->rq_server;

	nlmsvc_task = kthread_run(lockd, rqstp, serv->sv_name);
	if (IS_ERR(nlmsvc_task)) {
		error = PTR_ERR(nlmsvc_task);
		nlmsvc_task = NULL;
		nlmsvc_serv = NULL;
		printk(KERN_WARNING
			"lockd_up: kthread_run failed, error=%d\n", error);
		svc_exit_thread(rqstp);
		goto destroy_and_out;
	}

	/*
	 * Note: svc_serv structures have an initial use count of 1,
	 * so we exit through here on both success and failure.
	 */
destroy_and_out:
	svc_destroy(serv);
out:
	if (!error)
		nlmsvc_users++;
	mutex_unlock(&nlmsvc_mutex);
	return error;
}
EXPORT_SYMBOL(lockd_up);

/*
 * Decrement the user count and bring down lockd if we're the last.
 */
void
lockd_down(void)
{
	mutex_lock(&nlmsvc_mutex);
	if (nlmsvc_users) {
		if (--nlmsvc_users)
			goto out;
	} else {
		printk(KERN_ERR "lockd_down: no users! task=%p\n",
			nlmsvc_task);
		BUG();
	}

	if (!nlmsvc_task) {
		printk(KERN_ERR "lockd_down: no lockd running.\n");
		BUG();
	}
	kthread_stop(nlmsvc_task);
out:
	mutex_unlock(&nlmsvc_mutex);
}
EXPORT_SYMBOL(lockd_down);

#ifdef CONFIG_SYSCTL

/*
 * Sysctl parameters (same as module parameters, different interface).
 */

static ctl_table nlm_sysctls[] = {
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nlm_grace_period",
		.data		= &nlm_grace_period,
		.maxlen		= sizeof(unsigned long),
		.mode		= 0644,
		.proc_handler	= &proc_doulongvec_minmax,
		.extra1		= (unsigned long *) &nlm_grace_period_min,
		.extra2		= (unsigned long *) &nlm_grace_period_max,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nlm_timeout",
		.data		= &nlm_timeout,
		.maxlen		= sizeof(unsigned long),
		.mode		= 0644,
		.proc_handler	= &proc_doulongvec_minmax,
		.extra1		= (unsigned long *) &nlm_timeout_min,
		.extra2		= (unsigned long *) &nlm_timeout_max,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nlm_udpport",
		.data		= &nlm_udpport,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.extra1		= (int *) &nlm_port_min,
		.extra2		= (int *) &nlm_port_max,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nlm_tcpport",
		.data		= &nlm_tcpport,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_minmax,
		.extra1		= (int *) &nlm_port_min,
		.extra2		= (int *) &nlm_port_max,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nsm_use_hostnames",
		.data		= &nsm_use_hostnames,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nsm_local_state",
		.data		= &nsm_local_state,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
	{ .ctl_name = 0 }
};

static ctl_table nlm_sysctl_dir[] = {
	{
		.ctl_name	= CTL_UNNUMBERED,
		.procname	= "nfs",
		.mode		= 0555,
		.child		= nlm_sysctls,
	},
	{ .ctl_name = 0 }
};

static ctl_table nlm_sysctl_root[] = {
	{
		.ctl_name	= CTL_FS,
		.procname	= "fs",
		.mode		= 0555,
		.child		= nlm_sysctl_dir,
	},
	{ .ctl_name = 0 }
};

#endif	/* CONFIG_SYSCTL */

/*
 * Module (and sysfs) parameters.
 */

#define param_set_min_max(name, type, which_strtol, min, max)		\
static int param_set_##name(const char *val, struct kernel_param *kp)	\
{									\
	char *endp;							\
	__typeof__(type) num = which_strtol(val, &endp, 0);		\
	if (endp == val || *endp || num < (min) || num > (max))		\
		return -EINVAL;						\
	*((int *) kp->arg) = num;					\
	return 0;							\
}

static inline int is_callback(u32 proc)
{
	return proc == NLMPROC_GRANTED
		|| proc == NLMPROC_GRANTED_MSG
		|| proc == NLMPROC_TEST_RES
		|| proc == NLMPROC_LOCK_RES
		|| proc == NLMPROC_CANCEL_RES
		|| proc == NLMPROC_UNLOCK_RES
		|| proc == NLMPROC_NSM_NOTIFY;
}


static int lockd_authenticate(struct svc_rqst *rqstp)
{
	rqstp->rq_client = NULL;
	switch (rqstp->rq_authop->flavour) {
		case RPC_AUTH_NULL:
		case RPC_AUTH_UNIX:
			if (rqstp->rq_proc == 0)
				return SVC_OK;
			if (is_callback(rqstp->rq_proc)) {
				/* Leave it to individual procedures to
				 * call nlmsvc_lookup_host(rqstp)
				 */
				return SVC_OK;
			}
			return svc_set_client(rqstp);
	}
	return SVC_DENIED;
}


param_set_min_max(port, int, simple_strtol, 0, 65535)
param_set_min_max(grace_period, unsigned long, simple_strtoul,
		  nlm_grace_period_min, nlm_grace_period_max)
param_set_min_max(timeout, unsigned long, simple_strtoul,
		  nlm_timeout_min, nlm_timeout_max)

MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
MODULE_LICENSE("GPL");

module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
		  &nlm_grace_period, 0644);
module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
		  &nlm_timeout, 0644);
module_param_call(nlm_udpport, param_set_port, param_get_int,
		  &nlm_udpport, 0644);
module_param_call(nlm_tcpport, param_set_port, param_get_int,
		  &nlm_tcpport, 0644);
module_param(nsm_use_hostnames, bool, 0644);

/*
 * Initialising and terminating the module.
 */

static int __init init_nlm(void)
{
#ifdef CONFIG_SYSCTL
	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
	return nlm_sysctl_table ? 0 : -ENOMEM;
#else
	return 0;
#endif
}

static void __exit exit_nlm(void)
{
	/* FIXME: delete all NLM clients */
	nlm_shutdown_hosts();
#ifdef CONFIG_SYSCTL
	unregister_sysctl_table(nlm_sysctl_table);
#endif
}

module_init(init_nlm);
module_exit(exit_nlm);

/*
 * Define NLM program and procedures
 */
static struct svc_version	nlmsvc_version1 = {
		.vs_vers	= 1,
		.vs_nproc	= 17,
		.vs_proc	= nlmsvc_procedures,
		.vs_xdrsize	= NLMSVC_XDRSIZE,
};
static struct svc_version	nlmsvc_version3 = {
		.vs_vers	= 3,
		.vs_nproc	= 24,
		.vs_proc	= nlmsvc_procedures,
		.vs_xdrsize	= NLMSVC_XDRSIZE,
};
#ifdef CONFIG_LOCKD_V4
static struct svc_version	nlmsvc_version4 = {
		.vs_vers	= 4,
		.vs_nproc	= 24,
		.vs_proc	= nlmsvc_procedures4,
		.vs_xdrsize	= NLMSVC_XDRSIZE,
};
#endif
static struct svc_version *	nlmsvc_version[] = {
	[1] = &nlmsvc_version1,
	[3] = &nlmsvc_version3,
#ifdef CONFIG_LOCKD_V4
	[4] = &nlmsvc_version4,
#endif
};

static struct svc_stat		nlmsvc_stats;

#define NLM_NRVERS	ARRAY_SIZE(nlmsvc_version)
static struct svc_program	nlmsvc_program = {
	.pg_prog		= NLM_PROGRAM,		/* program number */
	.pg_nvers		= NLM_NRVERS,		/* number of entries in nlmsvc_version */
	.pg_vers		= nlmsvc_version,	/* version table */
	.pg_name		= "lockd",		/* service name */
	.pg_class		= "nfsd",		/* share authentication with nfsd */
	.pg_stats		= &nlmsvc_stats,	/* stats table */
	.pg_authenticate = &lockd_authenticate	/* export authentication */
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/lockd/svc.c
	3	*
	4	* This is the central lockd service.
	5	*
	6	* FIXME: Separate the lockd NFS server functionality from the lockd NFS
	7	* client functionality. Oh why didn't Sun create two separate
	8	* services in the first place?
	9	*
	10	* Authors: Olaf Kirch (okir@monad.swb.de)
	11	*
	12	* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
	13	*/
	14
1da177e4 LT	15	#include <linux/module.h>
	16	#include <linux/init.h>
	17	#include <linux/sysctl.h>
	18	#include <linux/moduleparam.h>
	19
	20	#include <linux/sched.h>
	21	#include <linux/errno.h>
	22	#include <linux/in.h>
	23	#include <linux/uio.h>
	24	#include <linux/slab.h>
	25	#include <linux/smp.h>
	26	#include <linux/smp_lock.h>
353ab6e9	27	#include <linux/mutex.h>
d751a7cd	28	#include <linux/kthread.h>
83144186	29	#include <linux/freezer.h>
1da177e4 LT	30
	31	#include <linux/sunrpc/types.h>
	32	#include <linux/sunrpc/stats.h>
	33	#include <linux/sunrpc/clnt.h>
	34	#include <linux/sunrpc/svc.h>
	35	#include <linux/sunrpc/svcsock.h>
24e36663	36	#include <net/ip.h>
1da177e4	37	#include <linux/lockd/lockd.h>
460f5cac	38	#include <linux/lockd/sm_inter.h>
1da177e4 LT	39	#include <linux/nfs.h>
	40
	41	#define NLMDBG_FACILITY NLMDBG_SVC
	42	#define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
	43	#define ALLOWED_SIGS (sigmask(SIGKILL))
	44
	45	static struct svc_program nlmsvc_program;
	46
	47	struct nlmsvc_binding * nlmsvc_ops;
	48	EXPORT_SYMBOL(nlmsvc_ops);
	49
353ab6e9	50	static DEFINE_MUTEX(nlmsvc_mutex);
1da177e4	51	static unsigned int nlmsvc_users;
d751a7cd	52	static struct task_struct *nlmsvc_task;
24e36663	53	static struct svc_serv *nlmsvc_serv;
1da177e4 LT	54	int nlmsvc_grace_period;
	55	unsigned long nlmsvc_timeout;
	56
1da177e4 LT	57	/*
	58	* These can be set at insmod time (useful for NFS as root filesystem),
	59	* and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
	60	*/
	61	static unsigned long nlm_grace_period;
	62	static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
	63	static int nlm_udpport, nlm_tcpport;
abd1f500	64	int nsm_use_hostnames = 0;
1da177e4 LT	65
	66	/*
	67	* Constants needed for the sysctl interface.
	68	*/
	69	static const unsigned long nlm_grace_period_min = 0;
	70	static const unsigned long nlm_grace_period_max = 240;
	71	static const unsigned long nlm_timeout_min = 3;
	72	static const unsigned long nlm_timeout_max = 20;
	73	static const int nlm_port_min = 0, nlm_port_max = 65535;
	74
90d5b180	75	#ifdef CONFIG_SYSCTL
1da177e4	76	static struct ctl_table_header * nlm_sysctl_table;
90d5b180	77	#endif
1da177e4	78
9a8db97e	79	static unsigned long get_lockd_grace_period(void)
1da177e4	80	{
1da177e4 LT	81	/* Note: nlm_timeout should always be nonzero */
1da177e4 LT	82	if (nlm_grace_period)
9a8db97e	83	return roundup(nlm_grace_period, nlm_timeout) * HZ;
1da177e4	84	else
9a8db97e ME	85	return nlm_timeout * 5 * HZ;
	86	}
	87
	88	unsigned long get_nfs_grace_period(void)
	89	{
	90	unsigned long lockdgrace = get_lockd_grace_period();
	91	unsigned long nfsdgrace = 0;
	92
	93	if (nlmsvc_ops)
	94	nfsdgrace = nlmsvc_ops->get_grace_period();
	95
	96	return max(lockdgrace, nfsdgrace);
	97	}
	98	EXPORT_SYMBOL(get_nfs_grace_period);
	99
	100	static unsigned long set_grace_period(void)
	101	{
1da177e4	102	nlmsvc_grace_period = 1;
9a8db97e	103	return get_nfs_grace_period() + jiffies;
1da177e4 LT	104	}
	105
	106	static inline void clear_grace_period(void)
	107	{
	108	nlmsvc_grace_period = 0;
	109	}
	110
	111	/*
	112	* This is the lockd kernel thread
	113	*/
d751a7cd JL	114	static int
d751a7cd JL	115	lockd(void *vrqstp)
1da177e4	116	{
f97c650d	117	int err = 0, preverr = 0;
d751a7cd	118	struct svc_rqst *rqstp = vrqstp;
1da177e4 LT	119	unsigned long grace_period_expire;
1da177e4 LT	120
d751a7cd	121	/* try_to_freeze() is called from svc_recv() */
83144186	122	set_freezable();
1da177e4	123
d751a7cd	124	/* Allow SIGKILL to tell lockd to drop all of its locks */
1da177e4 LT	125	allow_signal(SIGKILL);
1da177e4 LT	126
1da177e4 LT	127	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
1da177e4 LT	128
d751a7cd JL	129	/*
	130	* FIXME: it would be nice if lockd didn't spend its entire life
	131	* running under the BKL. At the very least, it would be good to
	132	* have someone clarify what it's intended to protect here. I've
	133	* seen some handwavy posts about posix locking needing to be
	134	* done under the BKL, but it's far from clear.
	135	*/
	136	lock_kernel();
	137
1da177e4 LT	138	if (!nlm_timeout)
	139	nlm_timeout = LOCKD_DFLT_TIMEO;
	140	nlmsvc_timeout = nlm_timeout * HZ;
	141
	142	grace_period_expire = set_grace_period();
	143
	144	/*
	145	* The main request loop. We don't terminate until the last
d751a7cd	146	* NFS mount or NFS daemon has gone away.
1da177e4	147	*/
d751a7cd	148	while (!kthread_should_stop()) {
1da177e4	149	long timeout = MAX_SCHEDULE_TIMEOUT;
5216a8e7	150	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1da177e4 LT	151
	152	if (signalled()) {
	153	flush_signals(current);
	154	if (nlmsvc_ops) {
	155	nlmsvc_invalidate_all();
	156	grace_period_expire = set_grace_period();
	157	}
d751a7cd	158	continue;
1da177e4 LT	159	}
	160
	161	/*
	162	* Retry any blocked locks that have been notified by
	163	* the VFS. Don't do this during grace period.
	164	* (Theoretically, there shouldn't even be blocked locks
	165	* during grace period).
	166	*/
	167	if (!nlmsvc_grace_period) {
	168	timeout = nlmsvc_retry_blocked();
	169	} else if (time_before(grace_period_expire, jiffies))
	170	clear_grace_period();
	171
	172	/*
	173	* Find a socket with data available and call its
	174	* recvfrom routine.
	175	*/
6fb2b47f	176	err = svc_recv(rqstp, timeout);
f97c650d JL	177	if (err == -EAGAIN \|\| err == -EINTR) {
f97c650d JL	178	preverr = err;
1da177e4	179	continue;
f97c650d	180	}
1da177e4	181	if (err < 0) {
f97c650d JL	182	if (err != preverr) {
	183	printk(KERN_WARNING "%s: unexpected error "
	184	"from svc_recv (%d)\n", __func__, err);
	185	preverr = err;
	186	}
	187	schedule_timeout_interruptible(HZ);
	188	continue;
1da177e4	189	}
f97c650d	190	preverr = err;
1da177e4	191
ad06e4bd CL	192	dprintk("lockd: request from %s\n",
ad06e4bd CL	193	svc_print_addr(rqstp, buf, sizeof(buf)));
1da177e4	194
6fb2b47f	195	svc_process(rqstp);
1da177e4 LT	196	}
1da177e4 LT	197
2bd61579	198	flush_signals(current);
d751a7cd JL	199	if (nlmsvc_ops)
	200	nlmsvc_invalidate_all();
	201	nlm_shutdown_hosts();
2bd61579	202
d751a7cd JL	203	unlock_kernel();
	204
	205	nlmsvc_task = NULL;
	206	nlmsvc_serv = NULL;
46be925f	207
1da177e4 LT	208	/* Exit the RPC thread */
	209	svc_exit_thread(rqstp);
	210
d751a7cd	211	return 0;
1da177e4 LT	212	}
1da177e4 LT	213
482fb94e CL	214	/*
	215	* Make any sockets that are needed but not present.
	216	* If nlm_udpport or nlm_tcpport were set as module
	217	* options, make those sockets unconditionally
	218	*/
24e36663 N	219	static int make_socks(struct svc_serv *serv, int proto)
24e36663 N	220	{
482fb94e	221	static int warned;
a217813f	222	struct svc_xprt *xprt;
24e36663	223	int err = 0;
482fb94e	224
a217813f TT	225	if (proto == IPPROTO_UDP \|\| nlm_udpport) {
	226	xprt = svc_find_xprt(serv, "udp", 0, 0);
	227	if (!xprt)
d7c9f1ed TT	228	err = svc_create_xprt(serv, "udp", nlm_udpport,
d7c9f1ed TT	229	SVC_SOCK_DEFAULTS);
a217813f TT	230	else
	231	svc_xprt_put(xprt);
	232	}
	233	if (err >= 0 && (proto == IPPROTO_TCP \|\| nlm_tcpport)) {
	234	xprt = svc_find_xprt(serv, "tcp", 0, 0);
	235	if (!xprt)
d7c9f1ed TT	236	err = svc_create_xprt(serv, "tcp", nlm_tcpport,
d7c9f1ed TT	237	SVC_SOCK_DEFAULTS);
a217813f TT	238	else
	239	svc_xprt_put(xprt);
	240	}
482fb94e	241	if (err >= 0) {
7dcf91ec	242	warned = 0;
482fb94e CL	243	err = 0;
482fb94e CL	244	} else if (warned++ == 0)
7dcf91ec N	245	printk(KERN_WARNING
7dcf91ec N	246	"lockd_up: makesock failed, error=%d\n", err);
24e36663 N	247	return err;
	248	}
	249
1da177e4 LT	250	/*
	251	* Bring up the lockd process if it's not already up.
	252	*/
	253	int
24e36663	254	lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */
1da177e4	255	{
d751a7cd JL	256	struct svc_serv *serv;
	257	struct svc_rqst *rqstp;
	258	int error = 0;
1da177e4	259
353ab6e9	260	mutex_lock(&nlmsvc_mutex);
1da177e4 LT	261	/*
	262	* Check whether we're already up and running.
	263	*/
d751a7cd	264	if (nlmsvc_serv) {
4a3ae42d N	265	if (proto)
4a3ae42d N	266	error = make_socks(nlmsvc_serv, proto);
1da177e4	267	goto out;
24e36663	268	}
1da177e4 LT	269
	270	/*
	271	* Sanity check: if there's no pid,
	272	* we should be the first user ...
	273	*/
4a3ae42d	274	if (nlmsvc_users)
1da177e4 LT	275	printk(KERN_WARNING
	276	"lockd_up: no pid, %d users??\n", nlmsvc_users);
	277
	278	error = -ENOMEM;
bc591ccf	279	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
1da177e4 LT	280	if (!serv) {
	281	printk(KERN_WARNING "lockd_up: create service failed\n");
	282	goto out;
	283	}
	284
7dcf91ec	285	if ((error = make_socks(serv, proto)) < 0)
1da177e4	286	goto destroy_and_out;
1da177e4 LT	287
	288	/*
	289	* Create the kernel thread and wait for it to start.
	290	*/
d751a7cd JL	291	rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]);
	292	if (IS_ERR(rqstp)) {
	293	error = PTR_ERR(rqstp);
	294	printk(KERN_WARNING
	295	"lockd_up: svc_rqst allocation failed, error=%d\n",
	296	error);
	297	goto destroy_and_out;
	298	}
	299
	300	svc_sock_update_bufs(serv);
	301	nlmsvc_serv = rqstp->rq_server;
	302
	303	nlmsvc_task = kthread_run(lockd, rqstp, serv->sv_name);
	304	if (IS_ERR(nlmsvc_task)) {
	305	error = PTR_ERR(nlmsvc_task);
	306	nlmsvc_task = NULL;
	307	nlmsvc_serv = NULL;
1da177e4	308	printk(KERN_WARNING
d751a7cd JL	309	"lockd_up: kthread_run failed, error=%d\n", error);
d751a7cd JL	310	svc_exit_thread(rqstp);
1da177e4 LT	311	goto destroy_and_out;
1da177e4 LT	312	}
1da177e4 LT	313
	314	/*
	315	* Note: svc_serv structures have an initial use count of 1,
	316	* so we exit through here on both success and failure.
	317	*/
	318	destroy_and_out:
	319	svc_destroy(serv);
	320	out:
4a3ae42d N	321	if (!error)
4a3ae42d N	322	nlmsvc_users++;
353ab6e9	323	mutex_unlock(&nlmsvc_mutex);
1da177e4 LT	324	return error;
	325	}
	326	EXPORT_SYMBOL(lockd_up);
	327
	328	/*
	329	* Decrement the user count and bring down lockd if we're the last.
	330	*/
	331	void
	332	lockd_down(void)
	333	{
353ab6e9	334	mutex_lock(&nlmsvc_mutex);
1da177e4 LT	335	if (nlmsvc_users) {
	336	if (--nlmsvc_users)
	337	goto out;
d751a7cd JL	338	} else {
	339	printk(KERN_ERR "lockd_down: no users! task=%p\n",
	340	nlmsvc_task);
	341	BUG();
1da177e4	342	}
1da177e4	343
d751a7cd JL	344	if (!nlmsvc_task) {
	345	printk(KERN_ERR "lockd_down: no lockd running.\n");
	346	BUG();
1da177e4	347	}
d751a7cd	348	kthread_stop(nlmsvc_task);
1da177e4	349	out:
353ab6e9	350	mutex_unlock(&nlmsvc_mutex);
1da177e4 LT	351	}
	352	EXPORT_SYMBOL(lockd_down);
	353
90d5b180 CL	354	#ifdef CONFIG_SYSCTL
90d5b180 CL	355
1da177e4 LT	356	/*
	357	* Sysctl parameters (same as module parameters, different interface).
	358	*/
	359
1da177e4 LT	360	static ctl_table nlm_sysctls[] = {
	361	{
	362	.ctl_name = CTL_UNNUMBERED,
	363	.procname = "nlm_grace_period",
	364	.data = &nlm_grace_period,
7ee91ec1	365	.maxlen = sizeof(unsigned long),
1da177e4 LT	366	.mode = 0644,
	367	.proc_handler = &proc_doulongvec_minmax,
	368	.extra1 = (unsigned long *) &nlm_grace_period_min,
	369	.extra2 = (unsigned long *) &nlm_grace_period_max,
	370	},
	371	{
	372	.ctl_name = CTL_UNNUMBERED,
	373	.procname = "nlm_timeout",
	374	.data = &nlm_timeout,
7ee91ec1	375	.maxlen = sizeof(unsigned long),
1da177e4 LT	376	.mode = 0644,
	377	.proc_handler = &proc_doulongvec_minmax,
	378	.extra1 = (unsigned long *) &nlm_timeout_min,
	379	.extra2 = (unsigned long *) &nlm_timeout_max,
	380	},
	381	{
	382	.ctl_name = CTL_UNNUMBERED,
	383	.procname = "nlm_udpport",
	384	.data = &nlm_udpport,
	385	.maxlen = sizeof(int),
	386	.mode = 0644,
	387	.proc_handler = &proc_dointvec_minmax,
	388	.extra1 = (int *) &nlm_port_min,
	389	.extra2 = (int *) &nlm_port_max,
	390	},
	391	{
	392	.ctl_name = CTL_UNNUMBERED,
	393	.procname = "nlm_tcpport",
	394	.data = &nlm_tcpport,
	395	.maxlen = sizeof(int),
	396	.mode = 0644,
	397	.proc_handler = &proc_dointvec_minmax,
	398	.extra1 = (int *) &nlm_port_min,
	399	.extra2 = (int *) &nlm_port_max,
	400	},
abd1f500 OK	401	{
	402	.ctl_name = CTL_UNNUMBERED,
	403	.procname = "nsm_use_hostnames",
	404	.data = &nsm_use_hostnames,
	405	.maxlen = sizeof(int),
	406	.mode = 0644,
	407	.proc_handler = &proc_dointvec,
	408	},
460f5cac OK	409	{
	410	.ctl_name = CTL_UNNUMBERED,
	411	.procname = "nsm_local_state",
	412	.data = &nsm_local_state,
	413	.maxlen = sizeof(int),
	414	.mode = 0644,
	415	.proc_handler = &proc_dointvec,
	416	},
1da177e4 LT	417	{ .ctl_name = 0 }
	418	};
	419
	420	static ctl_table nlm_sysctl_dir[] = {
	421	{
	422	.ctl_name = CTL_UNNUMBERED,
	423	.procname = "nfs",
	424	.mode = 0555,
	425	.child = nlm_sysctls,
	426	},
	427	{ .ctl_name = 0 }
	428	};
	429
	430	static ctl_table nlm_sysctl_root[] = {
	431	{
	432	.ctl_name = CTL_FS,
	433	.procname = "fs",
	434	.mode = 0555,
	435	.child = nlm_sysctl_dir,
	436	},
	437	{ .ctl_name = 0 }
	438	};
	439
90d5b180 CL	440	#endif /* CONFIG_SYSCTL */
90d5b180 CL	441
1da177e4	442	/*
405ae7d3	443	* Module (and sysfs) parameters.
1da177e4 LT	444	*/
	445
	446	#define param_set_min_max(name, type, which_strtol, min, max) \
	447	static int param_set_##name(const char val, struct kernel_param kp) \
	448	{ \
	449	char *endp; \
	450	__typeof__(type) num = which_strtol(val, &endp, 0); \
	451	if (endp == val \|\| *endp \|\| num < (min) \|\| num > (max)) \
	452	return -EINVAL; \
	453	((int ) kp->arg) = num; \
	454	return 0; \
	455	}
	456
	457	static inline int is_callback(u32 proc)
	458	{
	459	return proc == NLMPROC_GRANTED
	460	\|\| proc == NLMPROC_GRANTED_MSG
	461	\|\| proc == NLMPROC_TEST_RES
	462	\|\| proc == NLMPROC_LOCK_RES
	463	\|\| proc == NLMPROC_CANCEL_RES
	464	\|\| proc == NLMPROC_UNLOCK_RES
	465	\|\| proc == NLMPROC_NSM_NOTIFY;
	466	}
	467
	468
	469	static int lockd_authenticate(struct svc_rqst *rqstp)
	470	{
	471	rqstp->rq_client = NULL;
	472	switch (rqstp->rq_authop->flavour) {
	473	case RPC_AUTH_NULL:
	474	case RPC_AUTH_UNIX:
	475	if (rqstp->rq_proc == 0)
	476	return SVC_OK;
	477	if (is_callback(rqstp->rq_proc)) {
	478	/* Leave it to individual procedures to
	479	* call nlmsvc_lookup_host(rqstp)
	480	*/
	481	return SVC_OK;
	482	}
	483	return svc_set_client(rqstp);
	484	}
	485	return SVC_DENIED;
	486	}
	487
	488
	489	param_set_min_max(port, int, simple_strtol, 0, 65535)
	490	param_set_min_max(grace_period, unsigned long, simple_strtoul,
	491	nlm_grace_period_min, nlm_grace_period_max)
	492	param_set_min_max(timeout, unsigned long, simple_strtoul,
	493	nlm_timeout_min, nlm_timeout_max)
	494
	495	MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
	496	MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
	497	MODULE_LICENSE("GPL");
	498
	499	module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
	500	&nlm_grace_period, 0644);
	501	module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
	502	&nlm_timeout, 0644);
	503	module_param_call(nlm_udpport, param_set_port, param_get_int,
	504	&nlm_udpport, 0644);
	505	module_param_call(nlm_tcpport, param_set_port, param_get_int,
	506	&nlm_tcpport, 0644);
abd1f500	507	module_param(nsm_use_hostnames, bool, 0644);
1da177e4 LT	508
	509	/*
	510	* Initialising and terminating the module.
	511	*/
	512
	513	static int __init init_nlm(void)
	514	{
90d5b180	515	#ifdef CONFIG_SYSCTL
0b4d4147	516	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
1da177e4	517	return nlm_sysctl_table ? 0 : -ENOMEM;
90d5b180 CL	518	#else
	519	return 0;
	520	#endif
1da177e4 LT	521	}
	522
	523	static void __exit exit_nlm(void)
	524	{
	525	/* FIXME: delete all NLM clients */
	526	nlm_shutdown_hosts();
90d5b180	527	#ifdef CONFIG_SYSCTL
1da177e4	528	unregister_sysctl_table(nlm_sysctl_table);
90d5b180	529	#endif
1da177e4 LT	530	}
	531
	532	module_init(init_nlm);
	533	module_exit(exit_nlm);
	534
	535	/*
	536	* Define NLM program and procedures
	537	*/
	538	static struct svc_version nlmsvc_version1 = {
	539	.vs_vers = 1,
	540	.vs_nproc = 17,
	541	.vs_proc = nlmsvc_procedures,
	542	.vs_xdrsize = NLMSVC_XDRSIZE,
	543	};
	544	static struct svc_version nlmsvc_version3 = {
	545	.vs_vers = 3,
	546	.vs_nproc = 24,
	547	.vs_proc = nlmsvc_procedures,
	548	.vs_xdrsize = NLMSVC_XDRSIZE,
	549	};
	550	#ifdef CONFIG_LOCKD_V4
	551	static struct svc_version nlmsvc_version4 = {
	552	.vs_vers = 4,
	553	.vs_nproc = 24,
	554	.vs_proc = nlmsvc_procedures4,
	555	.vs_xdrsize = NLMSVC_XDRSIZE,
	556	};
	557	#endif
	558	static struct svc_version * nlmsvc_version[] = {
	559	[1] = &nlmsvc_version1,
	560	[3] = &nlmsvc_version3,
	561	#ifdef CONFIG_LOCKD_V4
	562	[4] = &nlmsvc_version4,
	563	#endif
	564	};
	565
	566	static struct svc_stat nlmsvc_stats;
	567
e8c96f8c	568	#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
1da177e4 LT	569	static struct svc_program nlmsvc_program = {
	570	.pg_prog = NLM_PROGRAM, /* program number */
	571	.pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
	572	.pg_vers = nlmsvc_version, /* version table */
	573	.pg_name = "lockd", /* service name */
	574	.pg_class = "nfsd", /* share authentication with nfsd */
	575	.pg_stats = &nlmsvc_stats, /* stats table */
	576	.pg_authenticate = &lockd_authenticate /* export authentication */
	577	};