[GitHub/mt8127/android_kernel_alcatel_ttab.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/config.h>
#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/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 DECLARE_MUTEX(nlmsvc_sema);
static unsigned int		nlmsvc_users;
static pid_t			nlmsvc_pid;
int				nlmsvc_grace_period;
unsigned long			nlmsvc_timeout;

static DECLARE_MUTEX_LOCKED(lockd_start);
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;
	up(&lockd_start);

	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);

	}

	/*
	 * 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;

	down(&nlmsvc_sema);
	/*
	 * 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);
	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;
	}
	down(&lockd_start);

	/*
	 * 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:
	up(&nlmsvc_sema);
	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;

	down(&nlmsvc_sema);
	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:
	up(&nlmsvc_sema);
}
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(int),
		.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(int),
		.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	(sizeof(nlmsvc_version)/sizeof(nlmsvc_version[0]))
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
	15	#include <linux/config.h>
	16	#include <linux/module.h>
	17	#include <linux/init.h>
	18	#include <linux/sysctl.h>
	19	#include <linux/moduleparam.h>
	20
	21	#include <linux/sched.h>
	22	#include <linux/errno.h>
	23	#include <linux/in.h>
	24	#include <linux/uio.h>
	25	#include <linux/slab.h>
	26	#include <linux/smp.h>
	27	#include <linux/smp_lock.h>
	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
	46	static DECLARE_MUTEX(nlmsvc_sema);
	47	static unsigned int nlmsvc_users;
	48	static pid_t nlmsvc_pid;
	49	int nlmsvc_grace_period;
	50	unsigned long nlmsvc_timeout;
	51
	52	static DECLARE_MUTEX_LOCKED(lockd_start);
	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;
115	up(&lockd_start);
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
181	/*
182	* Check whether there's a new lockd process before
183	* shutting down the hosts and clearing the slot.
184	*/
185	if (!nlmsvc_pid \|\| current->pid == nlmsvc_pid) {
186	if (nlmsvc_ops)
187	nlmsvc_invalidate_all();
188	nlm_shutdown_hosts();
189	nlmsvc_pid = 0;
190	} else
191	printk(KERN_DEBUG
192	"lockd: new process, skipping host shutdown\n");
193	wake_up(&lockd_exit);
194
195	/* Exit the RPC thread */
196	svc_exit_thread(rqstp);
197
198	/* release rpciod */
199	rpciod_down();
200
201	/* Release module */
202	unlock_kernel();
203	module_put_and_exit(0);
204	}
205
206	/*
207	* Bring up the lockd process if it's not already up.
208	*/
209	int
210	lockd_up(void)
211	{
212	static int warned;
213	struct svc_serv * serv;
214	int error = 0;
215
216	down(&nlmsvc_sema);
217	/*
218	* Unconditionally increment the user count ... this is
219	* the number of clients who _want_ a lockd process.
220	*/
221	nlmsvc_users++;
222	/*
223	* Check whether we're already up and running.
224	*/
225	if (nlmsvc_pid)
226	goto out;
227
228	/*
229	* Sanity check: if there's no pid,
230	* we should be the first user ...
231	*/
232	if (nlmsvc_users > 1)
233	printk(KERN_WARNING
234	"lockd_up: no pid, %d users??\n", nlmsvc_users);
235
236	error = -ENOMEM;
237	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE);
238	if (!serv) {
239	printk(KERN_WARNING "lockd_up: create service failed\n");
240	goto out;
241	}
242
243	if ((error = svc_makesock(serv, IPPROTO_UDP, nlm_udpport)) < 0
244	#ifdef CONFIG_NFSD_TCP
245	\|\| (error = svc_makesock(serv, IPPROTO_TCP, nlm_tcpport)) < 0
246	#endif
247	) {
248	if (warned++ == 0)
249	printk(KERN_WARNING
250	"lockd_up: makesock failed, error=%d\n", error);
251	goto destroy_and_out;
252	}
253	warned = 0;
254
255	/*
256	* Create the kernel thread and wait for it to start.
257	*/
258	error = svc_create_thread(lockd, serv);
259	if (error) {
260	printk(KERN_WARNING
261	"lockd_up: create thread failed, error=%d\n", error);
262	goto destroy_and_out;
263	}
264	down(&lockd_start);
265
266	/*
267	* Note: svc_serv structures have an initial use count of 1,
268	* so we exit through here on both success and failure.
269	*/
270	destroy_and_out:
271	svc_destroy(serv);
272	out:
273	up(&nlmsvc_sema);
274	return error;
275	}
276	EXPORT_SYMBOL(lockd_up);
277
278	/*
279	* Decrement the user count and bring down lockd if we're the last.
280	*/
281	void
282	lockd_down(void)
283	{
284	static int warned;
285
286	down(&nlmsvc_sema);
287	if (nlmsvc_users) {
288	if (--nlmsvc_users)
289	goto out;
290	} else
291	printk(KERN_WARNING "lockd_down: no users! pid=%d\n", nlmsvc_pid);
292
293	if (!nlmsvc_pid) {
294	if (warned++ == 0)
295	printk(KERN_WARNING "lockd_down: no lockd running.\n");
296	goto out;
297	}
298	warned = 0;
299
300	kill_proc(nlmsvc_pid, SIGKILL, 1);
301	/*
302	* Wait for the lockd process to exit, but since we're holding
303	* the lockd semaphore, we can't wait around forever ...
304	*/
305	clear_thread_flag(TIF_SIGPENDING);
306	interruptible_sleep_on_timeout(&lockd_exit, HZ);
307	if (nlmsvc_pid) {
308	printk(KERN_WARNING
309	"lockd_down: lockd failed to exit, clearing pid\n");
310	nlmsvc_pid = 0;
311	}
312	spin_lock_irq(&current->sighand->siglock);
313	recalc_sigpending();
314	spin_unlock_irq(&current->sighand->siglock);
315	out:
316	up(&nlmsvc_sema);
317	}
318	EXPORT_SYMBOL(lockd_down);
319
320	/*
321	* Sysctl parameters (same as module parameters, different interface).
322	*/
323
324	/* Something that isn't CTL_ANY, CTL_NONE or a value that may clash. */
325	#define CTL_UNNUMBERED -2
326
327	static ctl_table nlm_sysctls[] = {
328	{
329	.ctl_name = CTL_UNNUMBERED,
330	.procname = "nlm_grace_period",
331	.data = &nlm_grace_period,
332	.maxlen = sizeof(int),
333	.mode = 0644,
334	.proc_handler = &proc_doulongvec_minmax,
335	.extra1 = (unsigned long *) &nlm_grace_period_min,
336	.extra2 = (unsigned long *) &nlm_grace_period_max,
337	},
338	{
339	.ctl_name = CTL_UNNUMBERED,
340	.procname = "nlm_timeout",
341	.data = &nlm_timeout,
342	.maxlen = sizeof(int),
343	.mode = 0644,
344	.proc_handler = &proc_doulongvec_minmax,
345	.extra1 = (unsigned long *) &nlm_timeout_min,
346	.extra2 = (unsigned long *) &nlm_timeout_max,
347	},
348	{
349	.ctl_name = CTL_UNNUMBERED,
350	.procname = "nlm_udpport",
351	.data = &nlm_udpport,
352	.maxlen = sizeof(int),
353	.mode = 0644,
354	.proc_handler = &proc_dointvec_minmax,
355	.extra1 = (int *) &nlm_port_min,
356	.extra2 = (int *) &nlm_port_max,
357	},
358	{
359	.ctl_name = CTL_UNNUMBERED,
360	.procname = "nlm_tcpport",
361	.data = &nlm_tcpport,
362	.maxlen = sizeof(int),
363	.mode = 0644,
364	.proc_handler = &proc_dointvec_minmax,
365	.extra1 = (int *) &nlm_port_min,
366	.extra2 = (int *) &nlm_port_max,
367	},
368	{ .ctl_name = 0 }
369	};
370
371	static ctl_table nlm_sysctl_dir[] = {
372	{
373	.ctl_name = CTL_UNNUMBERED,
374	.procname = "nfs",
375	.mode = 0555,
376	.child = nlm_sysctls,
377	},
378	{ .ctl_name = 0 }
379	};
380
381	static ctl_table nlm_sysctl_root[] = {
382	{
383	.ctl_name = CTL_FS,
384	.procname = "fs",
385	.mode = 0555,
386	.child = nlm_sysctl_dir,
387	},
388	{ .ctl_name = 0 }
389	};
390
391	/*
392	* Module (and driverfs) parameters.
393	*/
394
395	#define param_set_min_max(name, type, which_strtol, min, max) \
396	static int param_set_##name(const char val, struct kernel_param kp) \
397	{ \
398	char *endp; \
399	__typeof__(type) num = which_strtol(val, &endp, 0); \
400	if (endp == val \|\| *endp \|\| num < (min) \|\| num > (max)) \
401	return -EINVAL; \
402	((int ) kp->arg) = num; \
403	return 0; \
404	}
405
406	static inline int is_callback(u32 proc)
407	{
408	return proc == NLMPROC_GRANTED
409	\|\| proc == NLMPROC_GRANTED_MSG
410	\|\| proc == NLMPROC_TEST_RES
411	\|\| proc == NLMPROC_LOCK_RES
412	\|\| proc == NLMPROC_CANCEL_RES
413	\|\| proc == NLMPROC_UNLOCK_RES
414	\|\| proc == NLMPROC_NSM_NOTIFY;
415	}
416
417
418	static int lockd_authenticate(struct svc_rqst *rqstp)
419	{
420	rqstp->rq_client = NULL;
421	switch (rqstp->rq_authop->flavour) {
422	case RPC_AUTH_NULL:
423	case RPC_AUTH_UNIX:
424	if (rqstp->rq_proc == 0)
425	return SVC_OK;
426	if (is_callback(rqstp->rq_proc)) {
427	/* Leave it to individual procedures to
428	* call nlmsvc_lookup_host(rqstp)
429	*/
430	return SVC_OK;
431	}
432	return svc_set_client(rqstp);
433	}
434	return SVC_DENIED;
435	}
436
437
438	param_set_min_max(port, int, simple_strtol, 0, 65535)
439	param_set_min_max(grace_period, unsigned long, simple_strtoul,
440	nlm_grace_period_min, nlm_grace_period_max)
441	param_set_min_max(timeout, unsigned long, simple_strtoul,
442	nlm_timeout_min, nlm_timeout_max)
443
444	MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
445	MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
446	MODULE_LICENSE("GPL");
447
448	module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
449	&nlm_grace_period, 0644);
450	module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
451	&nlm_timeout, 0644);
452	module_param_call(nlm_udpport, param_set_port, param_get_int,
453	&nlm_udpport, 0644);
454	module_param_call(nlm_tcpport, param_set_port, param_get_int,
455	&nlm_tcpport, 0644);
456
457	/*
458	* Initialising and terminating the module.
459	*/
460
461	static int __init init_nlm(void)
462	{
463	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root, 0);
464	return nlm_sysctl_table ? 0 : -ENOMEM;
465	}
466
467	static void __exit exit_nlm(void)
468	{
469	/* FIXME: delete all NLM clients */
470	nlm_shutdown_hosts();
471	unregister_sysctl_table(nlm_sysctl_table);
472	}
473
474	module_init(init_nlm);
475	module_exit(exit_nlm);
476
477	/*
478	* Define NLM program and procedures
479	*/
480	static struct svc_version nlmsvc_version1 = {
481	.vs_vers = 1,
482	.vs_nproc = 17,
483	.vs_proc = nlmsvc_procedures,
484	.vs_xdrsize = NLMSVC_XDRSIZE,
485	};
486	static struct svc_version nlmsvc_version3 = {
487	.vs_vers = 3,
488	.vs_nproc = 24,
489	.vs_proc = nlmsvc_procedures,
490	.vs_xdrsize = NLMSVC_XDRSIZE,
491	};
492	#ifdef CONFIG_LOCKD_V4
493	static struct svc_version nlmsvc_version4 = {
494	.vs_vers = 4,
495	.vs_nproc = 24,
496	.vs_proc = nlmsvc_procedures4,
497	.vs_xdrsize = NLMSVC_XDRSIZE,
498	};
499	#endif
500	static struct svc_version * nlmsvc_version[] = {
501	[1] = &nlmsvc_version1,
502	[3] = &nlmsvc_version3,
503	#ifdef CONFIG_LOCKD_V4
504	[4] = &nlmsvc_version4,
505	#endif
506	};
507
508	static struct svc_stat nlmsvc_stats;
509
510	#define NLM_NRVERS (sizeof(nlmsvc_version)/sizeof(nlmsvc_version[0]))
511	static struct svc_program nlmsvc_program = {
512	.pg_prog = NLM_PROGRAM, /* program number */
513	.pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
514	.pg_vers = nlmsvc_version, /* version table */
515	.pg_name = "lockd", /* service name */
516	.pg_class = "nfsd", /* share authentication with nfsd */
517	.pg_stats = &nlmsvc_stats, /* stats table */
518	.pg_authenticate = &lockd_authenticate /* export authentication */
519	};