/* * 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_SYSCTLstatic struct ctl_table_header * nlm_sysctl_table;#endifstatic 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 intlockd(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. */voidlockd_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_V4static struct svc_version	nlmsvc_version4 = {		.vs_vers	= 4,		.vs_nproc	= 24,		.vs_proc	= nlmsvc_procedures4,		.vs_xdrsize	= NLMSVC_XDRSIZE,};#endifstatic 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 */};