[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;

/*
 * If the kernel has IPv6 support available, always listen for
 * both AF_INET and AF_INET6 requests.
 */
#if (defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)) && \
	defined(CONFIG_SUNRPC_REGISTER_V4)
static const sa_family_t	nlmsvc_family = AF_INET6;
#else	/* (CONFIG_IPV6 || CONFIG_IPV6_MODULE) && CONFIG_SUNRPC_REGISTER_V4 */
static const sa_family_t	nlmsvc_family = AF_INET;
#endif	/* (CONFIG_IPV6 || CONFIG_IPV6_MODULE) && CONFIG_SUNRPC_REGISTER_V4 */

/*
 * 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, 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, nlmsvc_family, 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
b064ec03 CL	55	/*
	56	* If the kernel has IPv6 support available, always listen for
	57	* both AF_INET and AF_INET6 requests.
	58	*/
	59	#if (defined(CONFIG_IPV6) \|\| defined(CONFIG_IPV6_MODULE)) && \
	60	defined(CONFIG_SUNRPC_REGISTER_V4)
	61	static const sa_family_t nlmsvc_family = AF_INET6;
	62	#else /* (CONFIG_IPV6 \|\| CONFIG_IPV6_MODULE) && CONFIG_SUNRPC_REGISTER_V4 */
	63	static const sa_family_t nlmsvc_family = AF_INET;
	64	#endif /* (CONFIG_IPV6 \|\| CONFIG_IPV6_MODULE) && CONFIG_SUNRPC_REGISTER_V4 */
	65
1da177e4 LT	66	/*
	67	* These can be set at insmod time (useful for NFS as root filesystem),
	68	* and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
	69	*/
	70	static unsigned long nlm_grace_period;
	71	static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
	72	static int nlm_udpport, nlm_tcpport;
	73
c72a476b JL	74	/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
	75	static unsigned int nlm_max_connections = 1024;
	76
1da177e4 LT	77	/*
	78	* Constants needed for the sysctl interface.
	79	*/
	80	static const unsigned long nlm_grace_period_min = 0;
	81	static const unsigned long nlm_grace_period_max = 240;
	82	static const unsigned long nlm_timeout_min = 3;
	83	static const unsigned long nlm_timeout_max = 20;
	84	static const int nlm_port_min = 0, nlm_port_max = 65535;
	85
90d5b180	86	#ifdef CONFIG_SYSCTL
1da177e4	87	static struct ctl_table_header * nlm_sysctl_table;
90d5b180	88	#endif
1da177e4	89
9a8db97e	90	static unsigned long get_lockd_grace_period(void)
1da177e4	91	{
1da177e4 LT	92	/* Note: nlm_timeout should always be nonzero */
1da177e4 LT	93	if (nlm_grace_period)
9a8db97e	94	return roundup(nlm_grace_period, nlm_timeout) * HZ;
1da177e4	95	else
9a8db97e ME	96	return nlm_timeout * 5 * HZ;
	97	}
	98
af558e33 BF	99	static struct lock_manager lockd_manager = {
af558e33 BF	100	};
9a8db97e	101
c8ab5f2a	102	static void grace_ender(struct work_struct *not_used)
9a8db97e	103	{
af558e33	104	locks_end_grace(&lockd_manager);
1da177e4 LT	105	}
1da177e4 LT	106
c8ab5f2a BF	107	static DECLARE_DELAYED_WORK(grace_period_end, grace_ender);
	108
	109	static void set_grace_period(void)
1da177e4	110	{
af558e33	111	unsigned long grace_period = get_lockd_grace_period();
c8ab5f2a	112
af558e33	113	locks_start_grace(&lockd_manager);
c8ab5f2a BF	114	cancel_delayed_work_sync(&grace_period_end);
c8ab5f2a BF	115	schedule_delayed_work(&grace_period_end, grace_period);
1da177e4 LT	116	}
	117
	118	/*
	119	* This is the lockd kernel thread
	120	*/
d751a7cd JL	121	static int
d751a7cd JL	122	lockd(void *vrqstp)
1da177e4	123	{
f97c650d	124	int err = 0, preverr = 0;
d751a7cd	125	struct svc_rqst *rqstp = vrqstp;
1da177e4	126
d751a7cd	127	/* try_to_freeze() is called from svc_recv() */
83144186	128	set_freezable();
1da177e4	129
d751a7cd	130	/* Allow SIGKILL to tell lockd to drop all of its locks */
1da177e4 LT	131	allow_signal(SIGKILL);
1da177e4 LT	132
1da177e4 LT	133	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
1da177e4 LT	134
d751a7cd JL	135	/*
	136	* FIXME: it would be nice if lockd didn't spend its entire life
	137	* running under the BKL. At the very least, it would be good to
	138	* have someone clarify what it's intended to protect here. I've
	139	* seen some handwavy posts about posix locking needing to be
	140	* done under the BKL, but it's far from clear.
	141	*/
	142	lock_kernel();
	143
1da177e4 LT	144	if (!nlm_timeout)
	145	nlm_timeout = LOCKD_DFLT_TIMEO;
	146	nlmsvc_timeout = nlm_timeout * HZ;
	147
c8ab5f2a	148	set_grace_period();
1da177e4 LT	149
	150	/*
	151	* The main request loop. We don't terminate until the last
d751a7cd	152	* NFS mount or NFS daemon has gone away.
1da177e4	153	*/
d751a7cd	154	while (!kthread_should_stop()) {
1da177e4	155	long timeout = MAX_SCHEDULE_TIMEOUT;
5216a8e7	156	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1da177e4	157
c72a476b JL	158	/* update sv_maxconn if it has changed */
	159	rqstp->rq_server->sv_maxconn = nlm_max_connections;
	160
1da177e4 LT	161	if (signalled()) {
	162	flush_signals(current);
	163	if (nlmsvc_ops) {
	164	nlmsvc_invalidate_all();
c8ab5f2a	165	set_grace_period();
1da177e4	166	}
d751a7cd	167	continue;
1da177e4 LT	168	}
1da177e4 LT	169
8fafa900 BF	170	timeout = nlmsvc_retry_blocked();
8fafa900 BF	171
1da177e4 LT	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	196	}
2bd61579	197	flush_signals(current);
c8ab5f2a	198	cancel_delayed_work_sync(&grace_period_end);
2c5e7615	199	locks_end_grace(&lockd_manager);
d751a7cd JL	200	if (nlmsvc_ops)
	201	nlmsvc_invalidate_all();
	202	nlm_shutdown_hosts();
d751a7cd	203	unlock_kernel();
d751a7cd	204	return 0;
1da177e4 LT	205	}
1da177e4 LT	206
d3fe5ea7 CL	207	static int create_lockd_listener(struct svc_serv serv, char name,
	208	unsigned short port)
	209	{
	210	struct svc_xprt *xprt;
	211
	212	xprt = svc_find_xprt(serv, name, 0, 0);
	213	if (xprt == NULL)
	214	return svc_create_xprt(serv, name, port, SVC_SOCK_DEFAULTS);
	215
	216	svc_xprt_put(xprt);
	217	return 0;
	218	}
	219
482fb94e	220	/*
8c3916f4 CL	221	* Ensure there are active UDP and TCP listeners for lockd.
	222	*
	223	* Even if we have only TCP NFS mounts and/or TCP NFSDs, some
	224	* local services (such as rpc.statd) still require UDP, and
	225	* some NFS servers do not yet support NLM over TCP.
	226	*
	227	* Returns zero if all listeners are available; otherwise a
	228	* negative errno value is returned.
482fb94e	229	*/
8c3916f4	230	static int make_socks(struct svc_serv *serv)
24e36663	231	{
482fb94e	232	static int warned;
0dba7c2a	233	int err;
482fb94e	234
d3fe5ea7	235	err = create_lockd_listener(serv, "udp", nlm_udpport);
0dba7c2a CL	236	if (err < 0)
	237	goto out_err;
	238
	239	err = create_lockd_listener(serv, "tcp", nlm_tcpport);
	240	if (err < 0)
	241	goto out_err;
	242
	243	warned = 0;
	244	return 0;
	245
	246	out_err:
	247	if (warned++ == 0)
7dcf91ec	248	printk(KERN_WARNING
0dba7c2a	249	"lockd_up: makesock failed, error=%d\n", err);
24e36663 N	250	return err;
	251	}
	252
1da177e4 LT	253	/*
	254	* Bring up the lockd process if it's not already up.
	255	*/
26a41409	256	int lockd_up(void)
1da177e4	257	{
d751a7cd	258	struct svc_serv *serv;
d751a7cd	259	int error = 0;
1da177e4	260
353ab6e9	261	mutex_lock(&nlmsvc_mutex);
1da177e4 LT	262	/*
	263	* Check whether we're already up and running.
	264	*/
8c3916f4	265	if (nlmsvc_rqst)
1da177e4 LT	266	goto out;
	267
	268	/*
	269	* Sanity check: if there's no pid,
	270	* we should be the first user ...
	271	*/
4a3ae42d	272	if (nlmsvc_users)
1da177e4 LT	273	printk(KERN_WARNING
	274	"lockd_up: no pid, %d users??\n", nlmsvc_users);
	275
	276	error = -ENOMEM;
b064ec03	277	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, nlmsvc_family, NULL);
1da177e4 LT	278	if (!serv) {
	279	printk(KERN_WARNING "lockd_up: create service failed\n");
	280	goto out;
	281	}
	282
8c3916f4 CL	283	error = make_socks(serv);
8c3916f4 CL	284	if (error < 0)
1da177e4	285	goto destroy_and_out;
1da177e4 LT	286
	287	/*
	288	* Create the kernel thread and wait for it to start.
	289	*/
abd1ec4e JL	290	nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0]);
	291	if (IS_ERR(nlmsvc_rqst)) {
	292	error = PTR_ERR(nlmsvc_rqst);
	293	nlmsvc_rqst = NULL;
d751a7cd JL	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);
c72a476b	301	serv->sv_maxconn = nlm_max_connections;
d751a7cd	302
abd1ec4e	303	nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, serv->sv_name);
d751a7cd JL	304	if (IS_ERR(nlmsvc_task)) {
d751a7cd JL	305	error = PTR_ERR(nlmsvc_task);
abd1ec4e	306	svc_exit_thread(nlmsvc_rqst);
d751a7cd	307	nlmsvc_task = NULL;
abd1ec4e	308	nlmsvc_rqst = NULL;
1da177e4	309	printk(KERN_WARNING
d751a7cd	310	"lockd_up: kthread_run failed, error=%d\n", error);
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;
1da177e4 LT	325	}
2de59872	326	EXPORT_SYMBOL_GPL(lockd_up);
1da177e4 LT	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);
abd1ec4e JL	349	svc_exit_thread(nlmsvc_rqst);
	350	nlmsvc_task = NULL;
	351	nlmsvc_rqst = NULL;
1da177e4	352	out:
353ab6e9	353	mutex_unlock(&nlmsvc_mutex);
1da177e4	354	}
2de59872	355	EXPORT_SYMBOL_GPL(lockd_down);
1da177e4	356
90d5b180 CL	357	#ifdef CONFIG_SYSCTL
90d5b180 CL	358
1da177e4 LT	359	/*
	360	* Sysctl parameters (same as module parameters, different interface).
	361	*/
	362
1da177e4 LT	363	static ctl_table nlm_sysctls[] = {
	364	{
	365	.ctl_name = CTL_UNNUMBERED,
	366	.procname = "nlm_grace_period",
	367	.data = &nlm_grace_period,
7ee91ec1	368	.maxlen = sizeof(unsigned long),
1da177e4 LT	369	.mode = 0644,
	370	.proc_handler = &proc_doulongvec_minmax,
	371	.extra1 = (unsigned long *) &nlm_grace_period_min,
	372	.extra2 = (unsigned long *) &nlm_grace_period_max,
	373	},
	374	{
	375	.ctl_name = CTL_UNNUMBERED,
	376	.procname = "nlm_timeout",
	377	.data = &nlm_timeout,
7ee91ec1	378	.maxlen = sizeof(unsigned long),
1da177e4 LT	379	.mode = 0644,
	380	.proc_handler = &proc_doulongvec_minmax,
	381	.extra1 = (unsigned long *) &nlm_timeout_min,
	382	.extra2 = (unsigned long *) &nlm_timeout_max,
	383	},
	384	{
	385	.ctl_name = CTL_UNNUMBERED,
	386	.procname = "nlm_udpport",
	387	.data = &nlm_udpport,
	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	},
	394	{
	395	.ctl_name = CTL_UNNUMBERED,
	396	.procname = "nlm_tcpport",
	397	.data = &nlm_tcpport,
	398	.maxlen = sizeof(int),
	399	.mode = 0644,
	400	.proc_handler = &proc_dointvec_minmax,
	401	.extra1 = (int *) &nlm_port_min,
	402	.extra2 = (int *) &nlm_port_max,
	403	},
abd1f500 OK	404	{
	405	.ctl_name = CTL_UNNUMBERED,
	406	.procname = "nsm_use_hostnames",
	407	.data = &nsm_use_hostnames,
	408	.maxlen = sizeof(int),
	409	.mode = 0644,
	410	.proc_handler = &proc_dointvec,
	411	},
460f5cac OK	412	{
	413	.ctl_name = CTL_UNNUMBERED,
	414	.procname = "nsm_local_state",
	415	.data = &nsm_local_state,
	416	.maxlen = sizeof(int),
	417	.mode = 0644,
	418	.proc_handler = &proc_dointvec,
	419	},
1da177e4 LT	420	{ .ctl_name = 0 }
	421	};
	422
	423	static ctl_table nlm_sysctl_dir[] = {
	424	{
	425	.ctl_name = CTL_UNNUMBERED,
	426	.procname = "nfs",
	427	.mode = 0555,
	428	.child = nlm_sysctls,
	429	},
	430	{ .ctl_name = 0 }
	431	};
	432
	433	static ctl_table nlm_sysctl_root[] = {
	434	{
	435	.ctl_name = CTL_FS,
	436	.procname = "fs",
	437	.mode = 0555,
	438	.child = nlm_sysctl_dir,
	439	},
	440	{ .ctl_name = 0 }
	441	};
	442
90d5b180 CL	443	#endif /* CONFIG_SYSCTL */
90d5b180 CL	444
1da177e4	445	/*
405ae7d3	446	* Module (and sysfs) parameters.
1da177e4 LT	447	*/
	448
	449	#define param_set_min_max(name, type, which_strtol, min, max) \
	450	static int param_set_##name(const char val, struct kernel_param kp) \
	451	{ \
	452	char *endp; \
	453	__typeof__(type) num = which_strtol(val, &endp, 0); \
	454	if (endp == val \|\| *endp \|\| num < (min) \|\| num > (max)) \
	455	return -EINVAL; \
	456	((int ) kp->arg) = num; \
	457	return 0; \
	458	}
	459
	460	static inline int is_callback(u32 proc)
	461	{
	462	return proc == NLMPROC_GRANTED
	463	\|\| proc == NLMPROC_GRANTED_MSG
	464	\|\| proc == NLMPROC_TEST_RES
	465	\|\| proc == NLMPROC_LOCK_RES
	466	\|\| proc == NLMPROC_CANCEL_RES
	467	\|\| proc == NLMPROC_UNLOCK_RES
	468	\|\| proc == NLMPROC_NSM_NOTIFY;
	469	}
	470
	471
	472	static int lockd_authenticate(struct svc_rqst *rqstp)
	473	{
	474	rqstp->rq_client = NULL;
	475	switch (rqstp->rq_authop->flavour) {
	476	case RPC_AUTH_NULL:
	477	case RPC_AUTH_UNIX:
	478	if (rqstp->rq_proc == 0)
	479	return SVC_OK;
	480	if (is_callback(rqstp->rq_proc)) {
	481	/* Leave it to individual procedures to
	482	* call nlmsvc_lookup_host(rqstp)
	483	*/
	484	return SVC_OK;
	485	}
	486	return svc_set_client(rqstp);
	487	}
	488	return SVC_DENIED;
	489	}
	490
	491
	492	param_set_min_max(port, int, simple_strtol, 0, 65535)
	493	param_set_min_max(grace_period, unsigned long, simple_strtoul,
	494	nlm_grace_period_min, nlm_grace_period_max)
	495	param_set_min_max(timeout, unsigned long, simple_strtoul,
	496	nlm_timeout_min, nlm_timeout_max)
	497
	498	MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
	499	MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
	500	MODULE_LICENSE("GPL");
	501
	502	module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
	503	&nlm_grace_period, 0644);
	504	module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
	505	&nlm_timeout, 0644);
	506	module_param_call(nlm_udpport, param_set_port, param_get_int,
	507	&nlm_udpport, 0644);
	508	module_param_call(nlm_tcpport, param_set_port, param_get_int,
	509	&nlm_tcpport, 0644);
abd1f500	510	module_param(nsm_use_hostnames, bool, 0644);
c72a476b	511	module_param(nlm_max_connections, uint, 0644);
1da177e4 LT	512
	513	/*
	514	* Initialising and terminating the module.
	515	*/
	516
	517	static int __init init_nlm(void)
	518	{
90d5b180	519	#ifdef CONFIG_SYSCTL
0b4d4147	520	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
1da177e4	521	return nlm_sysctl_table ? 0 : -ENOMEM;
90d5b180 CL	522	#else
	523	return 0;
	524	#endif
1da177e4 LT	525	}
	526
	527	static void __exit exit_nlm(void)
	528	{
	529	/* FIXME: delete all NLM clients */
	530	nlm_shutdown_hosts();
90d5b180	531	#ifdef CONFIG_SYSCTL
1da177e4	532	unregister_sysctl_table(nlm_sysctl_table);
90d5b180	533	#endif
1da177e4 LT	534	}
	535
	536	module_init(init_nlm);
	537	module_exit(exit_nlm);
	538
	539	/*
	540	* Define NLM program and procedures
	541	*/
	542	static struct svc_version nlmsvc_version1 = {
	543	.vs_vers = 1,
	544	.vs_nproc = 17,
	545	.vs_proc = nlmsvc_procedures,
	546	.vs_xdrsize = NLMSVC_XDRSIZE,
	547	};
	548	static struct svc_version nlmsvc_version3 = {
	549	.vs_vers = 3,
	550	.vs_nproc = 24,
	551	.vs_proc = nlmsvc_procedures,
	552	.vs_xdrsize = NLMSVC_XDRSIZE,
	553	};
	554	#ifdef CONFIG_LOCKD_V4
	555	static struct svc_version nlmsvc_version4 = {
	556	.vs_vers = 4,
	557	.vs_nproc = 24,
	558	.vs_proc = nlmsvc_procedures4,
	559	.vs_xdrsize = NLMSVC_XDRSIZE,
	560	};
	561	#endif
	562	static struct svc_version * nlmsvc_version[] = {
	563	[1] = &nlmsvc_version1,
	564	[3] = &nlmsvc_version3,
	565	#ifdef CONFIG_LOCKD_V4
	566	[4] = &nlmsvc_version4,
	567	#endif
	568	};
	569
	570	static struct svc_stat nlmsvc_stats;
	571
e8c96f8c	572	#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
1da177e4 LT	573	static struct svc_program nlmsvc_program = {
	574	.pg_prog = NLM_PROGRAM, /* program number */
	575	.pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
	576	.pg_vers = nlmsvc_version, /* version table */
	577	.pg_name = "lockd", /* service name */
	578	.pg_class = "nfsd", /* share authentication with nfsd */
	579	.pg_stats = &nlmsvc_stats, /* stats table */
	580	.pg_authenticate = &lockd_authenticate /* export authentication */
	581	};