[deliverable/linux.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/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_GPL(nlmsvc_ops);

static DEFINE_MUTEX(nlmsvc_mutex);
static unsigned int		nlmsvc_users;
static struct task_struct	*nlmsvc_task;
static struct svc_rqst		*nlmsvc_rqst;
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;

/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
static unsigned int		nlm_max_connections = 1024;

/*
 * 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;
}

static struct lock_manager lockd_manager = {
};

static void grace_ender(struct work_struct *not_used)
{
	locks_end_grace(&lockd_manager);
}

static DECLARE_DELAYED_WORK(grace_period_end, grace_ender);

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

	locks_start_grace(&lockd_manager);
	cancel_delayed_work_sync(&grace_period_end);
	schedule_delayed_work(&grace_period_end, grace_period);
}

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

	/* 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;

	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]);

		/* update sv_maxconn if it has changed */
		rqstp->rq_server->sv_maxconn = nlm_max_connections;

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

		timeout = nlmsvc_retry_blocked();

		/*
		 * 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);
	cancel_delayed_work_sync(&grace_period_end);
	locks_end_grace(&lockd_manager);
	if (nlmsvc_ops)
		nlmsvc_invalidate_all();
	nlm_shutdown_hosts();
	unlock_kernel();
	return 0;
}

static int create_lockd_listener(struct svc_serv *serv, char *name,
				 unsigned short port)
{
	struct svc_xprt *xprt;

	xprt = svc_find_xprt(serv, name, 0, 0);
	if (xprt == NULL)
		return svc_create_xprt(serv, name, PF_INET,
					port, SVC_SOCK_DEFAULTS);

	svc_xprt_put(xprt);
	return 0;
}

/*
 * Ensure there are active UDP and TCP listeners for lockd.
 *
 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
 * local services (such as rpc.statd) still require UDP, and
 * some NFS servers do not yet support NLM over TCP.
 *
 * Returns zero if all listeners are available; otherwise a
 * negative errno value is returned.
 */
static int make_socks(struct svc_serv *serv)
{
	static int warned;
	int err;

	err = create_lockd_listener(serv, "udp", nlm_udpport);
	if (err < 0)
		goto out_err;

	err = create_lockd_listener(serv, "tcp", nlm_tcpport);
	if (err < 0)
		goto out_err;

	warned = 0;
	return 0;

out_err:
	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(void)
{
	struct svc_serv *serv;
	int		error = 0;

	mutex_lock(&nlmsvc_mutex);
	/*
	 * Check whether we're already up and running.
	 */
	if (nlmsvc_rqst)
		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;
	}

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

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

	svc_sock_update_bufs(serv);
	serv->sv_maxconn = nlm_max_connections;

	nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, serv->sv_name);
	if (IS_ERR(nlmsvc_task)) {
		error = PTR_ERR(nlmsvc_task);
		svc_exit_thread(nlmsvc_rqst);
		nlmsvc_task = NULL;
		nlmsvc_rqst = NULL;
		printk(KERN_WARNING
			"lockd_up: kthread_run failed, error=%d\n", error);
		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_GPL(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);
	svc_exit_thread(nlmsvc_rqst);
	nlmsvc_task = NULL;
	nlmsvc_rqst = NULL;
out:
	mutex_unlock(&nlmsvc_mutex);
}
EXPORT_SYMBOL_GPL(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);
module_param(nlm_max_connections, uint, 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 LT	37	#include <linux/lockd/lockd.h>
	38	#include <linux/nfs.h>
	39
	40	#define NLMDBG_FACILITY NLMDBG_SVC
	41	#define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
	42	#define ALLOWED_SIGS (sigmask(SIGKILL))
	43
	44	static struct svc_program nlmsvc_program;
	45
	46	struct nlmsvc_binding * nlmsvc_ops;
2de59872	47	EXPORT_SYMBOL_GPL(nlmsvc_ops);
1da177e4	48
353ab6e9	49	static DEFINE_MUTEX(nlmsvc_mutex);
1da177e4	50	static unsigned int nlmsvc_users;
d751a7cd	51	static struct task_struct *nlmsvc_task;
abd1ec4e	52	static struct svc_rqst *nlmsvc_rqst;
1da177e4 LT	53	unsigned long nlmsvc_timeout;
1da177e4 LT	54
1da177e4 LT	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
c72a476b JL	63	/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
	64	static unsigned int nlm_max_connections = 1024;
	65
1da177e4 LT	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
af558e33 BF	88	static struct lock_manager lockd_manager = {
af558e33 BF	89	};
9a8db97e	90
c8ab5f2a	91	static void grace_ender(struct work_struct *not_used)
9a8db97e	92	{
af558e33	93	locks_end_grace(&lockd_manager);
1da177e4 LT	94	}
1da177e4 LT	95
c8ab5f2a BF	96	static DECLARE_DELAYED_WORK(grace_period_end, grace_ender);
	97
	98	static void set_grace_period(void)
1da177e4	99	{
af558e33	100	unsigned long grace_period = get_lockd_grace_period();
c8ab5f2a	101
af558e33	102	locks_start_grace(&lockd_manager);
c8ab5f2a BF	103	cancel_delayed_work_sync(&grace_period_end);
c8ab5f2a BF	104	schedule_delayed_work(&grace_period_end, grace_period);
1da177e4 LT	105	}
	106
	107	/*
	108	* This is the lockd kernel thread
	109	*/
d751a7cd JL	110	static int
d751a7cd JL	111	lockd(void *vrqstp)
1da177e4	112	{
f97c650d	113	int err = 0, preverr = 0;
d751a7cd	114	struct svc_rqst *rqstp = vrqstp;
1da177e4	115
d751a7cd	116	/* try_to_freeze() is called from svc_recv() */
83144186	117	set_freezable();
1da177e4	118
d751a7cd	119	/* Allow SIGKILL to tell lockd to drop all of its locks */
1da177e4 LT	120	allow_signal(SIGKILL);
1da177e4 LT	121
1da177e4 LT	122	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
1da177e4 LT	123
d751a7cd JL	124	/*
	125	* FIXME: it would be nice if lockd didn't spend its entire life
	126	* running under the BKL. At the very least, it would be good to
	127	* have someone clarify what it's intended to protect here. I've
	128	* seen some handwavy posts about posix locking needing to be
	129	* done under the BKL, but it's far from clear.
	130	*/
	131	lock_kernel();
	132
1da177e4 LT	133	if (!nlm_timeout)
	134	nlm_timeout = LOCKD_DFLT_TIMEO;
	135	nlmsvc_timeout = nlm_timeout * HZ;
	136
c8ab5f2a	137	set_grace_period();
1da177e4 LT	138
	139	/*
	140	* The main request loop. We don't terminate until the last
d751a7cd	141	* NFS mount or NFS daemon has gone away.
1da177e4	142	*/
d751a7cd	143	while (!kthread_should_stop()) {
1da177e4	144	long timeout = MAX_SCHEDULE_TIMEOUT;
5216a8e7	145	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1da177e4	146
c72a476b JL	147	/* update sv_maxconn if it has changed */
	148	rqstp->rq_server->sv_maxconn = nlm_max_connections;
	149
1da177e4 LT	150	if (signalled()) {
	151	flush_signals(current);
	152	if (nlmsvc_ops) {
	153	nlmsvc_invalidate_all();
c8ab5f2a	154	set_grace_period();
1da177e4	155	}
d751a7cd	156	continue;
1da177e4 LT	157	}
1da177e4 LT	158
8fafa900 BF	159	timeout = nlmsvc_retry_blocked();
8fafa900 BF	160
1da177e4 LT	161	/*
	162	* Find a socket with data available and call its
	163	* recvfrom routine.
	164	*/
6fb2b47f	165	err = svc_recv(rqstp, timeout);
f97c650d JL	166	if (err == -EAGAIN \|\| err == -EINTR) {
f97c650d JL	167	preverr = err;
1da177e4	168	continue;
f97c650d	169	}
1da177e4	170	if (err < 0) {
f97c650d JL	171	if (err != preverr) {
	172	printk(KERN_WARNING "%s: unexpected error "
	173	"from svc_recv (%d)\n", __func__, err);
	174	preverr = err;
	175	}
	176	schedule_timeout_interruptible(HZ);
	177	continue;
1da177e4	178	}
f97c650d	179	preverr = err;
1da177e4	180
ad06e4bd CL	181	dprintk("lockd: request from %s\n",
ad06e4bd CL	182	svc_print_addr(rqstp, buf, sizeof(buf)));
1da177e4	183
6fb2b47f	184	svc_process(rqstp);
1da177e4	185	}
2bd61579	186	flush_signals(current);
c8ab5f2a	187	cancel_delayed_work_sync(&grace_period_end);
2c5e7615	188	locks_end_grace(&lockd_manager);
d751a7cd JL	189	if (nlmsvc_ops)
	190	nlmsvc_invalidate_all();
	191	nlm_shutdown_hosts();
d751a7cd	192	unlock_kernel();
d751a7cd	193	return 0;
1da177e4 LT	194	}
1da177e4 LT	195
d3fe5ea7 CL	196	static int create_lockd_listener(struct svc_serv serv, char name,
	197	unsigned short port)
	198	{
	199	struct svc_xprt *xprt;
	200
	201	xprt = svc_find_xprt(serv, name, 0, 0);
	202	if (xprt == NULL)
26298caa	203	return svc_create_xprt(serv, name, PF_INET,
9652ada3	204	port, SVC_SOCK_DEFAULTS);
d3fe5ea7 CL	205
	206	svc_xprt_put(xprt);
	207	return 0;
	208	}
	209
482fb94e	210	/*
8c3916f4 CL	211	* Ensure there are active UDP and TCP listeners for lockd.
	212	*
	213	* Even if we have only TCP NFS mounts and/or TCP NFSDs, some
	214	* local services (such as rpc.statd) still require UDP, and
	215	* some NFS servers do not yet support NLM over TCP.
	216	*
	217	* Returns zero if all listeners are available; otherwise a
	218	* negative errno value is returned.
482fb94e	219	*/
8c3916f4	220	static int make_socks(struct svc_serv *serv)
24e36663	221	{
482fb94e	222	static int warned;
0dba7c2a	223	int err;
482fb94e	224
d3fe5ea7	225	err = create_lockd_listener(serv, "udp", nlm_udpport);
0dba7c2a CL	226	if (err < 0)
	227	goto out_err;
	228
	229	err = create_lockd_listener(serv, "tcp", nlm_tcpport);
	230	if (err < 0)
	231	goto out_err;
	232
	233	warned = 0;
	234	return 0;
	235
	236	out_err:
	237	if (warned++ == 0)
7dcf91ec	238	printk(KERN_WARNING
0dba7c2a	239	"lockd_up: makesock failed, error=%d\n", err);
24e36663 N	240	return err;
	241	}
	242
1da177e4 LT	243	/*
	244	* Bring up the lockd process if it's not already up.
	245	*/
26a41409	246	int lockd_up(void)
1da177e4	247	{
d751a7cd	248	struct svc_serv *serv;
d751a7cd	249	int error = 0;
1da177e4	250
353ab6e9	251	mutex_lock(&nlmsvc_mutex);
1da177e4 LT	252	/*
	253	* Check whether we're already up and running.
	254	*/
8c3916f4	255	if (nlmsvc_rqst)
1da177e4 LT	256	goto out;
	257
	258	/*
	259	* Sanity check: if there's no pid,
	260	* we should be the first user ...
	261	*/
4a3ae42d	262	if (nlmsvc_users)
1da177e4 LT	263	printk(KERN_WARNING
	264	"lockd_up: no pid, %d users??\n", nlmsvc_users);
	265
	266	error = -ENOMEM;
49a9072f	267	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
1da177e4 LT	268	if (!serv) {
	269	printk(KERN_WARNING "lockd_up: create service failed\n");
	270	goto out;
	271	}
	272
8c3916f4 CL	273	error = make_socks(serv);
8c3916f4 CL	274	if (error < 0)
1da177e4	275	goto destroy_and_out;
1da177e4 LT	276
	277	/*
	278	* Create the kernel thread and wait for it to start.
	279	*/
abd1ec4e JL	280	nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0]);
	281	if (IS_ERR(nlmsvc_rqst)) {
	282	error = PTR_ERR(nlmsvc_rqst);
	283	nlmsvc_rqst = NULL;
d751a7cd JL	284	printk(KERN_WARNING
	285	"lockd_up: svc_rqst allocation failed, error=%d\n",
	286	error);
	287	goto destroy_and_out;
	288	}
	289
	290	svc_sock_update_bufs(serv);
c72a476b	291	serv->sv_maxconn = nlm_max_connections;
d751a7cd	292
abd1ec4e	293	nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, serv->sv_name);
d751a7cd JL	294	if (IS_ERR(nlmsvc_task)) {
d751a7cd JL	295	error = PTR_ERR(nlmsvc_task);
abd1ec4e	296	svc_exit_thread(nlmsvc_rqst);
d751a7cd	297	nlmsvc_task = NULL;
abd1ec4e	298	nlmsvc_rqst = NULL;
1da177e4	299	printk(KERN_WARNING
d751a7cd	300	"lockd_up: kthread_run failed, error=%d\n", error);
1da177e4 LT	301	goto destroy_and_out;
1da177e4 LT	302	}
1da177e4 LT	303
	304	/*
	305	* Note: svc_serv structures have an initial use count of 1,
	306	* so we exit through here on both success and failure.
	307	*/
	308	destroy_and_out:
	309	svc_destroy(serv);
	310	out:
4a3ae42d N	311	if (!error)
4a3ae42d N	312	nlmsvc_users++;
353ab6e9	313	mutex_unlock(&nlmsvc_mutex);
1da177e4 LT	314	return error;
1da177e4 LT	315	}
2de59872	316	EXPORT_SYMBOL_GPL(lockd_up);
1da177e4 LT	317
	318	/*
	319	* Decrement the user count and bring down lockd if we're the last.
	320	*/
	321	void
	322	lockd_down(void)
	323	{
353ab6e9	324	mutex_lock(&nlmsvc_mutex);
1da177e4 LT	325	if (nlmsvc_users) {
	326	if (--nlmsvc_users)
	327	goto out;
d751a7cd JL	328	} else {
	329	printk(KERN_ERR "lockd_down: no users! task=%p\n",
	330	nlmsvc_task);
	331	BUG();
1da177e4	332	}
1da177e4	333
d751a7cd JL	334	if (!nlmsvc_task) {
	335	printk(KERN_ERR "lockd_down: no lockd running.\n");
	336	BUG();
1da177e4	337	}
d751a7cd	338	kthread_stop(nlmsvc_task);
abd1ec4e JL	339	svc_exit_thread(nlmsvc_rqst);
	340	nlmsvc_task = NULL;
	341	nlmsvc_rqst = NULL;
1da177e4	342	out:
353ab6e9	343	mutex_unlock(&nlmsvc_mutex);
1da177e4	344	}
2de59872	345	EXPORT_SYMBOL_GPL(lockd_down);
1da177e4	346
90d5b180 CL	347	#ifdef CONFIG_SYSCTL
90d5b180 CL	348
1da177e4 LT	349	/*
	350	* Sysctl parameters (same as module parameters, different interface).
	351	*/
	352
1da177e4 LT	353	static ctl_table nlm_sysctls[] = {
	354	{
	355	.ctl_name = CTL_UNNUMBERED,
	356	.procname = "nlm_grace_period",
	357	.data = &nlm_grace_period,
7ee91ec1	358	.maxlen = sizeof(unsigned long),
1da177e4 LT	359	.mode = 0644,
	360	.proc_handler = &proc_doulongvec_minmax,
	361	.extra1 = (unsigned long *) &nlm_grace_period_min,
	362	.extra2 = (unsigned long *) &nlm_grace_period_max,
	363	},
	364	{
	365	.ctl_name = CTL_UNNUMBERED,
	366	.procname = "nlm_timeout",
	367	.data = &nlm_timeout,
7ee91ec1	368	.maxlen = sizeof(unsigned long),
1da177e4 LT	369	.mode = 0644,
	370	.proc_handler = &proc_doulongvec_minmax,
	371	.extra1 = (unsigned long *) &nlm_timeout_min,
	372	.extra2 = (unsigned long *) &nlm_timeout_max,
	373	},
	374	{
	375	.ctl_name = CTL_UNNUMBERED,
	376	.procname = "nlm_udpport",
	377	.data = &nlm_udpport,
	378	.maxlen = sizeof(int),
	379	.mode = 0644,
	380	.proc_handler = &proc_dointvec_minmax,
	381	.extra1 = (int *) &nlm_port_min,
	382	.extra2 = (int *) &nlm_port_max,
	383	},
	384	{
	385	.ctl_name = CTL_UNNUMBERED,
	386	.procname = "nlm_tcpport",
	387	.data = &nlm_tcpport,
	388	.maxlen = sizeof(int),
	389	.mode = 0644,
	390	.proc_handler = &proc_dointvec_minmax,
	391	.extra1 = (int *) &nlm_port_min,
	392	.extra2 = (int *) &nlm_port_max,
	393	},
abd1f500 OK	394	{
	395	.ctl_name = CTL_UNNUMBERED,
	396	.procname = "nsm_use_hostnames",
	397	.data = &nsm_use_hostnames,
	398	.maxlen = sizeof(int),
	399	.mode = 0644,
	400	.proc_handler = &proc_dointvec,
	401	},
460f5cac OK	402	{
	403	.ctl_name = CTL_UNNUMBERED,
	404	.procname = "nsm_local_state",
	405	.data = &nsm_local_state,
	406	.maxlen = sizeof(int),
	407	.mode = 0644,
	408	.proc_handler = &proc_dointvec,
	409	},
1da177e4 LT	410	{ .ctl_name = 0 }
	411	};
	412
	413	static ctl_table nlm_sysctl_dir[] = {
	414	{
	415	.ctl_name = CTL_UNNUMBERED,
	416	.procname = "nfs",
	417	.mode = 0555,
	418	.child = nlm_sysctls,
	419	},
	420	{ .ctl_name = 0 }
	421	};
	422
	423	static ctl_table nlm_sysctl_root[] = {
	424	{
	425	.ctl_name = CTL_FS,
	426	.procname = "fs",
	427	.mode = 0555,
	428	.child = nlm_sysctl_dir,
	429	},
	430	{ .ctl_name = 0 }
	431	};
	432
90d5b180 CL	433	#endif /* CONFIG_SYSCTL */
90d5b180 CL	434
1da177e4	435	/*
405ae7d3	436	* Module (and sysfs) parameters.
1da177e4 LT	437	*/
	438
	439	#define param_set_min_max(name, type, which_strtol, min, max) \
	440	static int param_set_##name(const char val, struct kernel_param kp) \
	441	{ \
	442	char *endp; \
	443	__typeof__(type) num = which_strtol(val, &endp, 0); \
	444	if (endp == val \|\| *endp \|\| num < (min) \|\| num > (max)) \
	445	return -EINVAL; \
	446	((int ) kp->arg) = num; \
	447	return 0; \
	448	}
	449
	450	static inline int is_callback(u32 proc)
	451	{
	452	return proc == NLMPROC_GRANTED
	453	\|\| proc == NLMPROC_GRANTED_MSG
	454	\|\| proc == NLMPROC_TEST_RES
	455	\|\| proc == NLMPROC_LOCK_RES
	456	\|\| proc == NLMPROC_CANCEL_RES
	457	\|\| proc == NLMPROC_UNLOCK_RES
	458	\|\| proc == NLMPROC_NSM_NOTIFY;
	459	}
	460
	461
	462	static int lockd_authenticate(struct svc_rqst *rqstp)
	463	{
	464	rqstp->rq_client = NULL;
	465	switch (rqstp->rq_authop->flavour) {
	466	case RPC_AUTH_NULL:
	467	case RPC_AUTH_UNIX:
	468	if (rqstp->rq_proc == 0)
	469	return SVC_OK;
	470	if (is_callback(rqstp->rq_proc)) {
	471	/* Leave it to individual procedures to
	472	* call nlmsvc_lookup_host(rqstp)
	473	*/
	474	return SVC_OK;
	475	}
	476	return svc_set_client(rqstp);
	477	}
	478	return SVC_DENIED;
	479	}
	480
	481
	482	param_set_min_max(port, int, simple_strtol, 0, 65535)
	483	param_set_min_max(grace_period, unsigned long, simple_strtoul,
	484	nlm_grace_period_min, nlm_grace_period_max)
	485	param_set_min_max(timeout, unsigned long, simple_strtoul,
	486	nlm_timeout_min, nlm_timeout_max)
	487
	488	MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
	489	MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
	490	MODULE_LICENSE("GPL");
	491
	492	module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
	493	&nlm_grace_period, 0644);
	494	module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
	495	&nlm_timeout, 0644);
	496	module_param_call(nlm_udpport, param_set_port, param_get_int,
	497	&nlm_udpport, 0644);
	498	module_param_call(nlm_tcpport, param_set_port, param_get_int,
	499	&nlm_tcpport, 0644);
abd1f500	500	module_param(nsm_use_hostnames, bool, 0644);
c72a476b	501	module_param(nlm_max_connections, uint, 0644);
1da177e4 LT	502
	503	/*
	504	* Initialising and terminating the module.
	505	*/
	506
	507	static int __init init_nlm(void)
	508	{
90d5b180	509	#ifdef CONFIG_SYSCTL
0b4d4147	510	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
1da177e4	511	return nlm_sysctl_table ? 0 : -ENOMEM;
90d5b180 CL	512	#else
	513	return 0;
	514	#endif
1da177e4 LT	515	}
	516
	517	static void __exit exit_nlm(void)
	518	{
	519	/* FIXME: delete all NLM clients */
	520	nlm_shutdown_hosts();
90d5b180	521	#ifdef CONFIG_SYSCTL
1da177e4	522	unregister_sysctl_table(nlm_sysctl_table);
90d5b180	523	#endif
1da177e4 LT	524	}
	525
	526	module_init(init_nlm);
	527	module_exit(exit_nlm);
	528
	529	/*
	530	* Define NLM program and procedures
	531	*/
	532	static struct svc_version nlmsvc_version1 = {
	533	.vs_vers = 1,
	534	.vs_nproc = 17,
	535	.vs_proc = nlmsvc_procedures,
	536	.vs_xdrsize = NLMSVC_XDRSIZE,
	537	};
	538	static struct svc_version nlmsvc_version3 = {
	539	.vs_vers = 3,
	540	.vs_nproc = 24,
	541	.vs_proc = nlmsvc_procedures,
	542	.vs_xdrsize = NLMSVC_XDRSIZE,
	543	};
	544	#ifdef CONFIG_LOCKD_V4
	545	static struct svc_version nlmsvc_version4 = {
	546	.vs_vers = 4,
	547	.vs_nproc = 24,
	548	.vs_proc = nlmsvc_procedures4,
	549	.vs_xdrsize = NLMSVC_XDRSIZE,
	550	};
	551	#endif
	552	static struct svc_version * nlmsvc_version[] = {
	553	[1] = &nlmsvc_version1,
	554	[3] = &nlmsvc_version3,
	555	#ifdef CONFIG_LOCKD_V4
	556	[4] = &nlmsvc_version4,
	557	#endif
	558	};
	559
	560	static struct svc_stat nlmsvc_stats;
	561
e8c96f8c	562	#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
1da177e4 LT	563	static struct svc_program nlmsvc_program = {
	564	.pg_prog = NLM_PROGRAM, /* program number */
	565	.pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
	566	.pg_vers = nlmsvc_version, /* version table */
	567	.pg_name = "lockd", /* service name */
	568	.pg_class = "nfsd", /* share authentication with nfsd */
	569	.pg_stats = &nlmsvc_stats, /* stats table */
	570	.pg_authenticate = &lockd_authenticate /* export authentication */
	571	};