[linux-2.6-block.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/sunrpc/types.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/lockd/lockd.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 pid_t			nlmsvc_pid;
int				nlmsvc_grace_period;
unsigned long			nlmsvc_timeout;

static DECLARE_COMPLETION(lockd_start_done);
static DECLARE_WAIT_QUEUE_HEAD(lockd_exit);

/*
 * 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;

/*
 * 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;

static struct ctl_table_header * nlm_sysctl_table;

static unsigned long set_grace_period(void)
{
	unsigned long grace_period;

	/* Note: nlm_timeout should always be nonzero */
	if (nlm_grace_period)
		grace_period = ((nlm_grace_period + nlm_timeout - 1)
				/ nlm_timeout) * nlm_timeout * HZ;
	else
		grace_period = nlm_timeout * 5 * HZ;
	nlmsvc_grace_period = 1;
	return grace_period + jiffies;
}

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

/*
 * This is the lockd kernel thread
 */
static void
lockd(struct svc_rqst *rqstp)
{
	struct svc_serv	*serv = rqstp->rq_server;
	int		err = 0;
	unsigned long grace_period_expire;

	/* Lock module and set up kernel thread */
	/* lockd_up is waiting for us to startup, so will
	 * be holding a reference to this module, so it
	 * is safe to just claim another reference
	 */
	__module_get(THIS_MODULE);
	lock_kernel();

	/*
	 * Let our maker know we're running.
	 */
	nlmsvc_pid = current->pid;
	complete(&lockd_start_done);

	daemonize("lockd");

	/* Process request with signals blocked, but allow SIGKILL.  */
	allow_signal(SIGKILL);

	/* kick rpciod */
	rpciod_up();

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

	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, and we've been sent a
	 * signal, or else another process has taken over our job.
	 */
	while ((nlmsvc_users || !signalled()) && nlmsvc_pid == current->pid) {
		long timeout = MAX_SCHEDULE_TIMEOUT;

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

		/*
		 * 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(serv, rqstp, timeout);
		if (err == -EAGAIN || err == -EINTR)
			continue;
		if (err < 0) {
			printk(KERN_WARNING
			       "lockd: terminating on error %d\n",
			       -err);
			break;
		}

		dprintk("lockd: request from %08x\n",
			(unsigned)ntohl(rqstp->rq_addr.sin_addr.s_addr));

		svc_process(serv, rqstp);

	}

	flush_signals(current);

	/*
	 * Check whether there's a new lockd process before
	 * shutting down the hosts and clearing the slot.
	 */
	if (!nlmsvc_pid || current->pid == nlmsvc_pid) {
		if (nlmsvc_ops)
			nlmsvc_invalidate_all();
		nlm_shutdown_hosts();
		nlmsvc_pid = 0;
	} else
		printk(KERN_DEBUG
			"lockd: new process, skipping host shutdown\n");
	wake_up(&lockd_exit);

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

	/* release rpciod */
	rpciod_down();

	/* Release module */
	unlock_kernel();
	module_put_and_exit(0);
}

/*
 * Bring up the lockd process if it's not already up.
 */
int
lockd_up(void)
{
	static int		warned;
	struct svc_serv *	serv;
	int			error = 0;

	mutex_lock(&nlmsvc_mutex);
	/*
	 * Unconditionally increment the user count ... this is
	 * the number of clients who _want_ a lockd process.
	 */
	nlmsvc_users++; 
	/*
	 * Check whether we're already up and running.
	 */
	if (nlmsvc_pid)
		goto out;

	/*
	 * Sanity check: if there's no pid,
	 * we should be the first user ...
	 */
	if (nlmsvc_users > 1)
		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 = svc_makesock(serv, IPPROTO_UDP, nlm_udpport)) < 0 
#ifdef CONFIG_NFSD_TCP
	 || (error = svc_makesock(serv, IPPROTO_TCP, nlm_tcpport)) < 0
#endif
		) {
		if (warned++ == 0) 
			printk(KERN_WARNING
				"lockd_up: makesock failed, error=%d\n", error);
		goto destroy_and_out;
	} 
	warned = 0;

	/*
	 * Create the kernel thread and wait for it to start.
	 */
	error = svc_create_thread(lockd, serv);
	if (error) {
		printk(KERN_WARNING
			"lockd_up: create thread failed, error=%d\n", error);
		goto destroy_and_out;
	}
	wait_for_completion(&lockd_start_done);

	/*
	 * 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:
	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)
{
	static int warned;

	mutex_lock(&nlmsvc_mutex);
	if (nlmsvc_users) {
		if (--nlmsvc_users)
			goto out;
	} else
		printk(KERN_WARNING "lockd_down: no users! pid=%d\n", nlmsvc_pid);

	if (!nlmsvc_pid) {
		if (warned++ == 0)
			printk(KERN_WARNING "lockd_down: no lockd running.\n"); 
		goto out;
	}
	warned = 0;

	kill_proc(nlmsvc_pid, SIGKILL, 1);
	/*
	 * Wait for the lockd process to exit, but since we're holding
	 * the lockd semaphore, we can't wait around forever ...
	 */
	clear_thread_flag(TIF_SIGPENDING);
	interruptible_sleep_on_timeout(&lockd_exit, HZ);
	if (nlmsvc_pid) {
		printk(KERN_WARNING 
			"lockd_down: lockd failed to exit, clearing pid\n");
		nlmsvc_pid = 0;
	}
	spin_lock_irq(&current->sighand->siglock);
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
out:
	mutex_unlock(&nlmsvc_mutex);
}
EXPORT_SYMBOL(lockd_down);

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

/* Something that isn't CTL_ANY, CTL_NONE or a value that may clash. */
#define CTL_UNNUMBERED		-2

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 = 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 }
};

/*
 * Module (and driverfs) 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);

/*
 * Initialising and terminating the module.
 */

static int __init init_nlm(void)
{
	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root, 0);
	return nlm_sysctl_table ? 0 : -ENOMEM;
}

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

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>
1da177e4 LT	28
	29	#include <linux/sunrpc/types.h>
	30	#include <linux/sunrpc/stats.h>
	31	#include <linux/sunrpc/clnt.h>
	32	#include <linux/sunrpc/svc.h>
	33	#include <linux/sunrpc/svcsock.h>
	34	#include <linux/lockd/lockd.h>
	35	#include <linux/nfs.h>
	36
	37	#define NLMDBG_FACILITY NLMDBG_SVC
	38	#define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
	39	#define ALLOWED_SIGS (sigmask(SIGKILL))
	40
	41	static struct svc_program nlmsvc_program;
	42
	43	struct nlmsvc_binding * nlmsvc_ops;
	44	EXPORT_SYMBOL(nlmsvc_ops);
	45
353ab6e9	46	static DEFINE_MUTEX(nlmsvc_mutex);
1da177e4 LT	47	static unsigned int nlmsvc_users;
	48	static pid_t nlmsvc_pid;
	49	int nlmsvc_grace_period;
	50	unsigned long nlmsvc_timeout;
	51
353ab6e9	52	static DECLARE_COMPLETION(lockd_start_done);
1da177e4 LT	53	static DECLARE_WAIT_QUEUE_HEAD(lockd_exit);
	54
	55	/*
	56	* These can be set at insmod time (useful for NFS as root filesystem),
	57	* and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
	58	*/
	59	static unsigned long nlm_grace_period;
	60	static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
	61	static int nlm_udpport, nlm_tcpport;
	62
	63	/*
	64	* Constants needed for the sysctl interface.
	65	*/
	66	static const unsigned long nlm_grace_period_min = 0;
	67	static const unsigned long nlm_grace_period_max = 240;
	68	static const unsigned long nlm_timeout_min = 3;
	69	static const unsigned long nlm_timeout_max = 20;
	70	static const int nlm_port_min = 0, nlm_port_max = 65535;
	71
	72	static struct ctl_table_header * nlm_sysctl_table;
	73
	74	static unsigned long set_grace_period(void)
	75	{
	76	unsigned long grace_period;
	77
	78	/* Note: nlm_timeout should always be nonzero */
	79	if (nlm_grace_period)
	80	grace_period = ((nlm_grace_period + nlm_timeout - 1)
	81	/ nlm_timeout) * nlm_timeout * HZ;
	82	else
	83	grace_period = nlm_timeout * 5 * HZ;
	84	nlmsvc_grace_period = 1;
	85	return grace_period + jiffies;
	86	}
	87
	88	static inline void clear_grace_period(void)
	89	{
	90	nlmsvc_grace_period = 0;
	91	}
	92
	93	/*
	94	* This is the lockd kernel thread
	95	*/
	96	static void
	97	lockd(struct svc_rqst *rqstp)
	98	{
	99	struct svc_serv *serv = rqstp->rq_server;
	100	int err = 0;
	101	unsigned long grace_period_expire;
	102
	103	/* Lock module and set up kernel thread */
	104	/* lockd_up is waiting for us to startup, so will
	105	* be holding a reference to this module, so it
	106	* is safe to just claim another reference
	107	*/
	108	__module_get(THIS_MODULE);
	109	lock_kernel();
	110
	111	/*
	112	* Let our maker know we're running.
	113	*/
	114	nlmsvc_pid = current->pid;
353ab6e9	115	complete(&lockd_start_done);
1da177e4 LT	116
	117	daemonize("lockd");
	118
	119	/* Process request with signals blocked, but allow SIGKILL. */
	120	allow_signal(SIGKILL);
	121
	122	/* kick rpciod */
	123	rpciod_up();
	124
	125	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
	126
	127	if (!nlm_timeout)
	128	nlm_timeout = LOCKD_DFLT_TIMEO;
	129	nlmsvc_timeout = nlm_timeout * HZ;
	130
	131	grace_period_expire = set_grace_period();
	132
	133	/*
	134	* The main request loop. We don't terminate until the last
	135	* NFS mount or NFS daemon has gone away, and we've been sent a
	136	* signal, or else another process has taken over our job.
	137	*/
	138	while ((nlmsvc_users \|\| !signalled()) && nlmsvc_pid == current->pid) {
	139	long timeout = MAX_SCHEDULE_TIMEOUT;
	140
	141	if (signalled()) {
	142	flush_signals(current);
	143	if (nlmsvc_ops) {
	144	nlmsvc_invalidate_all();
	145	grace_period_expire = set_grace_period();
	146	}
	147	}
	148
	149	/*
	150	* Retry any blocked locks that have been notified by
	151	* the VFS. Don't do this during grace period.
	152	* (Theoretically, there shouldn't even be blocked locks
	153	* during grace period).
	154	*/
	155	if (!nlmsvc_grace_period) {
	156	timeout = nlmsvc_retry_blocked();
	157	} else if (time_before(grace_period_expire, jiffies))
	158	clear_grace_period();
	159
	160	/*
	161	* Find a socket with data available and call its
	162	* recvfrom routine.
	163	*/
	164	err = svc_recv(serv, rqstp, timeout);
	165	if (err == -EAGAIN \|\| err == -EINTR)
	166	continue;
	167	if (err < 0) {
	168	printk(KERN_WARNING
	169	"lockd: terminating on error %d\n",
	170	-err);
	171	break;
	172	}
	173
	174	dprintk("lockd: request from %08x\n",
	175	(unsigned)ntohl(rqstp->rq_addr.sin_addr.s_addr));
	176
	177	svc_process(serv, rqstp);
	178
	179	}
180
2bd61579 TM	181	flush_signals(current);
2bd61579 TM	182
1da177e4 LT	183	/*
	184	* Check whether there's a new lockd process before
	185	* shutting down the hosts and clearing the slot.
	186	*/
	187	if (!nlmsvc_pid \|\| current->pid == nlmsvc_pid) {
	188	if (nlmsvc_ops)
	189	nlmsvc_invalidate_all();
	190	nlm_shutdown_hosts();
	191	nlmsvc_pid = 0;
	192	} else
	193	printk(KERN_DEBUG
	194	"lockd: new process, skipping host shutdown\n");
	195	wake_up(&lockd_exit);
46be925f	196
1da177e4 LT	197	/* Exit the RPC thread */
	198	svc_exit_thread(rqstp);
	199
	200	/* release rpciod */
	201	rpciod_down();
	202
	203	/* Release module */
	204	unlock_kernel();
	205	module_put_and_exit(0);
	206	}
	207
	208	/*
	209	* Bring up the lockd process if it's not already up.
	210	*/
	211	int
	212	lockd_up(void)
	213	{
	214	static int warned;
	215	struct svc_serv * serv;
	216	int error = 0;
	217
353ab6e9	218	mutex_lock(&nlmsvc_mutex);
1da177e4 LT	219	/*
	220	* Unconditionally increment the user count ... this is
	221	* the number of clients who _want_ a lockd process.
	222	*/
	223	nlmsvc_users++;
	224	/*
	225	* Check whether we're already up and running.
	226	*/
	227	if (nlmsvc_pid)
	228	goto out;
	229
	230	/*
	231	* Sanity check: if there's no pid,
	232	* we should be the first user ...
	233	*/
	234	if (nlmsvc_users > 1)
	235	printk(KERN_WARNING
	236	"lockd_up: no pid, %d users??\n", nlmsvc_users);
	237
	238	error = -ENOMEM;
bc591ccf	239	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
1da177e4 LT	240	if (!serv) {
	241	printk(KERN_WARNING "lockd_up: create service failed\n");
	242	goto out;
	243	}
	244
	245	if ((error = svc_makesock(serv, IPPROTO_UDP, nlm_udpport)) < 0
	246	#ifdef CONFIG_NFSD_TCP
	247	\|\| (error = svc_makesock(serv, IPPROTO_TCP, nlm_tcpport)) < 0
	248	#endif
	249	) {
	250	if (warned++ == 0)
	251	printk(KERN_WARNING
	252	"lockd_up: makesock failed, error=%d\n", error);
	253	goto destroy_and_out;
	254	}
	255	warned = 0;
	256
	257	/*
	258	* Create the kernel thread and wait for it to start.
	259	*/
	260	error = svc_create_thread(lockd, serv);
	261	if (error) {
	262	printk(KERN_WARNING
	263	"lockd_up: create thread failed, error=%d\n", error);
	264	goto destroy_and_out;
	265	}
353ab6e9	266	wait_for_completion(&lockd_start_done);
1da177e4 LT	267
	268	/*
	269	* Note: svc_serv structures have an initial use count of 1,
	270	* so we exit through here on both success and failure.
	271	*/
	272	destroy_and_out:
	273	svc_destroy(serv);
	274	out:
353ab6e9	275	mutex_unlock(&nlmsvc_mutex);
1da177e4 LT	276	return error;
	277	}
	278	EXPORT_SYMBOL(lockd_up);
	279
	280	/*
	281	* Decrement the user count and bring down lockd if we're the last.
	282	*/
	283	void
	284	lockd_down(void)
	285	{
	286	static int warned;
	287
353ab6e9	288	mutex_lock(&nlmsvc_mutex);
1da177e4 LT	289	if (nlmsvc_users) {
	290	if (--nlmsvc_users)
	291	goto out;
	292	} else
	293	printk(KERN_WARNING "lockd_down: no users! pid=%d\n", nlmsvc_pid);
	294
	295	if (!nlmsvc_pid) {
	296	if (warned++ == 0)
	297	printk(KERN_WARNING "lockd_down: no lockd running.\n");
	298	goto out;
	299	}
	300	warned = 0;
	301
	302	kill_proc(nlmsvc_pid, SIGKILL, 1);
	303	/*
	304	* Wait for the lockd process to exit, but since we're holding
	305	* the lockd semaphore, we can't wait around forever ...
	306	*/
	307	clear_thread_flag(TIF_SIGPENDING);
	308	interruptible_sleep_on_timeout(&lockd_exit, HZ);
	309	if (nlmsvc_pid) {
	310	printk(KERN_WARNING
	311	"lockd_down: lockd failed to exit, clearing pid\n");
	312	nlmsvc_pid = 0;
	313	}
	314	spin_lock_irq(&current->sighand->siglock);
	315	recalc_sigpending();
	316	spin_unlock_irq(&current->sighand->siglock);
	317	out:
353ab6e9	318	mutex_unlock(&nlmsvc_mutex);
1da177e4 LT	319	}
	320	EXPORT_SYMBOL(lockd_down);
	321
	322	/*
	323	* Sysctl parameters (same as module parameters, different interface).
	324	*/
	325
	326	/* Something that isn't CTL_ANY, CTL_NONE or a value that may clash. */
	327	#define CTL_UNNUMBERED -2
	328
	329	static ctl_table nlm_sysctls[] = {
	330	{
	331	.ctl_name = CTL_UNNUMBERED,
	332	.procname = "nlm_grace_period",
	333	.data = &nlm_grace_period,
7ee91ec1	334	.maxlen = sizeof(unsigned long),
1da177e4 LT	335	.mode = 0644,
	336	.proc_handler = &proc_doulongvec_minmax,
	337	.extra1 = (unsigned long *) &nlm_grace_period_min,
	338	.extra2 = (unsigned long *) &nlm_grace_period_max,
	339	},
	340	{
	341	.ctl_name = CTL_UNNUMBERED,
	342	.procname = "nlm_timeout",
	343	.data = &nlm_timeout,
7ee91ec1	344	.maxlen = sizeof(unsigned long),
1da177e4 LT	345	.mode = 0644,
	346	.proc_handler = &proc_doulongvec_minmax,
	347	.extra1 = (unsigned long *) &nlm_timeout_min,
	348	.extra2 = (unsigned long *) &nlm_timeout_max,
	349	},
	350	{
	351	.ctl_name = CTL_UNNUMBERED,
	352	.procname = "nlm_udpport",
	353	.data = &nlm_udpport,
	354	.maxlen = sizeof(int),
	355	.mode = 0644,
	356	.proc_handler = &proc_dointvec_minmax,
	357	.extra1 = (int *) &nlm_port_min,
	358	.extra2 = (int *) &nlm_port_max,
	359	},
	360	{
	361	.ctl_name = CTL_UNNUMBERED,
	362	.procname = "nlm_tcpport",
	363	.data = &nlm_tcpport,
	364	.maxlen = sizeof(int),
	365	.mode = 0644,
	366	.proc_handler = &proc_dointvec_minmax,
	367	.extra1 = (int *) &nlm_port_min,
	368	.extra2 = (int *) &nlm_port_max,
	369	},
	370	{ .ctl_name = 0 }
	371	};
	372
	373	static ctl_table nlm_sysctl_dir[] = {
	374	{
	375	.ctl_name = CTL_UNNUMBERED,
	376	.procname = "nfs",
	377	.mode = 0555,
	378	.child = nlm_sysctls,
	379	},
	380	{ .ctl_name = 0 }
	381	};
	382
	383	static ctl_table nlm_sysctl_root[] = {
	384	{
	385	.ctl_name = CTL_FS,
	386	.procname = "fs",
	387	.mode = 0555,
	388	.child = nlm_sysctl_dir,
	389	},
	390	{ .ctl_name = 0 }
	391	};
	392
	393	/*
	394	* Module (and driverfs) parameters.
	395	*/
	396
	397	#define param_set_min_max(name, type, which_strtol, min, max) \
	398	static int param_set_##name(const char val, struct kernel_param kp) \
	399	{ \
	400	char *endp; \
	401	__typeof__(type) num = which_strtol(val, &endp, 0); \
	402	if (endp == val \|\| *endp \|\| num < (min) \|\| num > (max)) \
	403	return -EINVAL; \
	404	((int ) kp->arg) = num; \
	405	return 0; \
	406	}
	407
	408	static inline int is_callback(u32 proc)
409	{
410	return proc == NLMPROC_GRANTED
411	\|\| proc == NLMPROC_GRANTED_MSG
412	\|\| proc == NLMPROC_TEST_RES
413	\|\| proc == NLMPROC_LOCK_RES
414	\|\| proc == NLMPROC_CANCEL_RES
415	\|\| proc == NLMPROC_UNLOCK_RES
416	\|\| proc == NLMPROC_NSM_NOTIFY;
417	}
418
419
420	static int lockd_authenticate(struct svc_rqst *rqstp)
421	{
422	rqstp->rq_client = NULL;
423	switch (rqstp->rq_authop->flavour) {
424	case RPC_AUTH_NULL:
425	case RPC_AUTH_UNIX:
426	if (rqstp->rq_proc == 0)
427	return SVC_OK;
428	if (is_callback(rqstp->rq_proc)) {
429	/* Leave it to individual procedures to
430	* call nlmsvc_lookup_host(rqstp)
431	*/
432	return SVC_OK;
433	}
434	return svc_set_client(rqstp);
435	}
436	return SVC_DENIED;
437	}
438
439
440	param_set_min_max(port, int, simple_strtol, 0, 65535)
441	param_set_min_max(grace_period, unsigned long, simple_strtoul,
442	nlm_grace_period_min, nlm_grace_period_max)
443	param_set_min_max(timeout, unsigned long, simple_strtoul,
444	nlm_timeout_min, nlm_timeout_max)
445
446	MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
447	MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
448	MODULE_LICENSE("GPL");
449
450	module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
451	&nlm_grace_period, 0644);
452	module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
453	&nlm_timeout, 0644);
454	module_param_call(nlm_udpport, param_set_port, param_get_int,
455	&nlm_udpport, 0644);
456	module_param_call(nlm_tcpport, param_set_port, param_get_int,
457	&nlm_tcpport, 0644);
458
459	/*
460	* Initialising and terminating the module.
461	*/
462
463	static int __init init_nlm(void)
464	{
465	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root, 0);
466	return nlm_sysctl_table ? 0 : -ENOMEM;
467	}
468
469	static void __exit exit_nlm(void)
470	{
471	/* FIXME: delete all NLM clients */
472	nlm_shutdown_hosts();
473	unregister_sysctl_table(nlm_sysctl_table);
474	}
475
476	module_init(init_nlm);
477	module_exit(exit_nlm);
478
479	/*
480	* Define NLM program and procedures
481	*/
482	static struct svc_version nlmsvc_version1 = {
483	.vs_vers = 1,
484	.vs_nproc = 17,
485	.vs_proc = nlmsvc_procedures,
486	.vs_xdrsize = NLMSVC_XDRSIZE,
487	};
488	static struct svc_version nlmsvc_version3 = {
489	.vs_vers = 3,
490	.vs_nproc = 24,
491	.vs_proc = nlmsvc_procedures,
492	.vs_xdrsize = NLMSVC_XDRSIZE,
493	};
494	#ifdef CONFIG_LOCKD_V4
495	static struct svc_version nlmsvc_version4 = {
496	.vs_vers = 4,
497	.vs_nproc = 24,
498	.vs_proc = nlmsvc_procedures4,
499	.vs_xdrsize = NLMSVC_XDRSIZE,
500	};
501	#endif
502	static struct svc_version * nlmsvc_version[] = {
503	[1] = &nlmsvc_version1,
504	[3] = &nlmsvc_version3,
505	#ifdef CONFIG_LOCKD_V4
506	[4] = &nlmsvc_version4,
507	#endif
508	};
509
510	static struct svc_stat nlmsvc_stats;
511
e8c96f8c	512	#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
1da177e4 LT	513	static struct svc_program nlmsvc_program = {
	514	.pg_prog = NLM_PROGRAM, /* program number */
	515	.pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
	516	.pg_vers = nlmsvc_version, /* version table */
	517	.pg_name = "lockd", /* service name */
	518	.pg_class = "nfsd", /* share authentication with nfsd */
	519	.pg_stats = &nlmsvc_stats, /* stats table */
	520	.pg_authenticate = &lockd_authenticate /* export authentication */
	521	};