[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / nfsd / nfssvc.c

/*
 * linux/fs/nfsd/nfssvc.c
 *
 * Central processing for nfsd.
 *
 * Authors:	Olaf Kirch (okir@monad.swb.de)
 *
 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/module.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <linux/errno.h>
#include <linux/nfs.h>
#include <linux/in.h>
#include <linux/uio.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/freezer.h>
#include <linux/fs_struct.h>

#include <linux/sunrpc/types.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/cache.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/stats.h>
#include <linux/nfsd/cache.h>
#include <linux/nfsd/syscall.h>
#include <linux/lockd/bind.h>
#include <linux/nfsacl.h>

#define NFSDDBG_FACILITY	NFSDDBG_SVC

/* these signals will be delivered to an nfsd thread 
 * when handling a request
 */
#define ALLOWED_SIGS	(sigmask(SIGKILL))
/* these signals will be delivered to an nfsd thread
 * when not handling a request. i.e. when waiting
 */
#define SHUTDOWN_SIGS	(sigmask(SIGKILL) | sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT))
/* if the last thread dies with SIGHUP, then the exports table is
 * left unchanged ( like 2.4-{0-9} ).  Any other signal will clear
 * the exports table (like 2.2).
 */
#define	SIG_NOCLEAN	SIGHUP

extern struct svc_program	nfsd_program;
static void			nfsd(struct svc_rqst *rqstp);
struct timeval			nfssvc_boot;
       struct svc_serv 		*nfsd_serv;
static atomic_t			nfsd_busy;
static unsigned long		nfsd_last_call;
static DEFINE_SPINLOCK(nfsd_call_lock);

#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
static struct svc_stat	nfsd_acl_svcstats;
static struct svc_version *	nfsd_acl_version[] = {
	[2] = &nfsd_acl_version2,
	[3] = &nfsd_acl_version3,
};

#define NFSD_ACL_MINVERS            2
#define NFSD_ACL_NRVERS		ARRAY_SIZE(nfsd_acl_version)
static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];

static struct svc_program	nfsd_acl_program = {
	.pg_prog		= NFS_ACL_PROGRAM,
	.pg_nvers		= NFSD_ACL_NRVERS,
	.pg_vers		= nfsd_acl_versions,
	.pg_name		= "nfsacl",
	.pg_class		= "nfsd",
	.pg_stats		= &nfsd_acl_svcstats,
	.pg_authenticate	= &svc_set_client,
};

static struct svc_stat	nfsd_acl_svcstats = {
	.program	= &nfsd_acl_program,
};
#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */

static struct svc_version *	nfsd_version[] = {
	[2] = &nfsd_version2,
#if defined(CONFIG_NFSD_V3)
	[3] = &nfsd_version3,
#endif
#if defined(CONFIG_NFSD_V4)
	[4] = &nfsd_version4,
#endif
};

#define NFSD_MINVERS    	2
#define NFSD_NRVERS		ARRAY_SIZE(nfsd_version)
static struct svc_version *nfsd_versions[NFSD_NRVERS];

struct svc_program		nfsd_program = {
#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
	.pg_next		= &nfsd_acl_program,
#endif
	.pg_prog		= NFS_PROGRAM,		/* program number */
	.pg_nvers		= NFSD_NRVERS,		/* nr of entries in nfsd_version */
	.pg_vers		= nfsd_versions,	/* version table */
	.pg_name		= "nfsd",		/* program name */
	.pg_class		= "nfsd",		/* authentication class */
	.pg_stats		= &nfsd_svcstats,	/* version table */
	.pg_authenticate	= &svc_set_client,	/* export authentication */

};

int nfsd_vers(int vers, enum vers_op change)
{
	if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
		return -1;
	switch(change) {
	case NFSD_SET:
		nfsd_versions[vers] = nfsd_version[vers];
#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
		if (vers < NFSD_ACL_NRVERS)
			nfsd_acl_versions[vers] = nfsd_acl_version[vers];
#endif
		break;
	case NFSD_CLEAR:
		nfsd_versions[vers] = NULL;
#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
		if (vers < NFSD_ACL_NRVERS)
			nfsd_acl_versions[vers] = NULL;
#endif
		break;
	case NFSD_TEST:
		return nfsd_versions[vers] != NULL;
	case NFSD_AVAIL:
		return nfsd_version[vers] != NULL;
	}
	return 0;
}
/*
 * Maximum number of nfsd processes
 */
#define	NFSD_MAXSERVS		8192

int nfsd_nrthreads(void)
{
	if (nfsd_serv == NULL)
		return 0;
	else
		return nfsd_serv->sv_nrthreads;
}

static int killsig;	/* signal that was used to kill last nfsd */
static void nfsd_last_thread(struct svc_serv *serv)
{
	/* When last nfsd thread exits we need to do some clean-up */
	struct svc_sock *svsk;
	list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
		lockd_down();
	nfsd_serv = NULL;
	nfsd_racache_shutdown();
	nfs4_state_shutdown();

	printk(KERN_WARNING "nfsd: last server has exited\n");
	if (killsig != SIG_NOCLEAN) {
		printk(KERN_WARNING "nfsd: unexporting all filesystems\n");
		nfsd_export_flush();
	}
}

void nfsd_reset_versions(void)
{
	int found_one = 0;
	int i;

	for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
		if (nfsd_program.pg_vers[i])
			found_one = 1;
	}

	if (!found_one) {
		for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
			nfsd_program.pg_vers[i] = nfsd_version[i];
#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
		for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
			nfsd_acl_program.pg_vers[i] =
				nfsd_acl_version[i];
#endif
	}
}

int nfsd_create_serv(void)
{
	int err = 0;
	lock_kernel();
	if (nfsd_serv) {
		svc_get(nfsd_serv);
		unlock_kernel();
		return 0;
	}
	if (nfsd_max_blksize == 0) {
		/* choose a suitable default */
		struct sysinfo i;
		si_meminfo(&i);
		/* Aim for 1/4096 of memory per thread
		 * This gives 1MB on 4Gig machines
		 * But only uses 32K on 128M machines.
		 * Bottom out at 8K on 32M and smaller.
		 * Of course, this is only a default.
		 */
		nfsd_max_blksize = NFSSVC_MAXBLKSIZE;
		i.totalram <<= PAGE_SHIFT - 12;
		while (nfsd_max_blksize > i.totalram &&
		       nfsd_max_blksize >= 8*1024*2)
			nfsd_max_blksize /= 2;
	}

	atomic_set(&nfsd_busy, 0);
	nfsd_serv = svc_create_pooled(&nfsd_program,
				      nfsd_max_blksize,
				      nfsd_last_thread,
				      nfsd, SIG_NOCLEAN, THIS_MODULE);
	if (nfsd_serv == NULL)
		err = -ENOMEM;
	unlock_kernel();
	do_gettimeofday(&nfssvc_boot);		/* record boot time */
	return err;
}

static int nfsd_init_socks(int port)
{
	int error;
	if (!list_empty(&nfsd_serv->sv_permsocks))
		return 0;

	error = lockd_up(IPPROTO_UDP);
	if (error >= 0) {
		error = svc_makesock(nfsd_serv, IPPROTO_UDP, port,
					SVC_SOCK_DEFAULTS);
		if (error < 0)
			lockd_down();
	}
	if (error < 0)
		return error;

#ifdef CONFIG_NFSD_TCP
	error = lockd_up(IPPROTO_TCP);
	if (error >= 0) {
		error = svc_makesock(nfsd_serv, IPPROTO_TCP, port,
					SVC_SOCK_DEFAULTS);
		if (error < 0)
			lockd_down();
	}
	if (error < 0)
		return error;
#endif
	return 0;
}

int nfsd_nrpools(void)
{
	if (nfsd_serv == NULL)
		return 0;
	else
		return nfsd_serv->sv_nrpools;
}

int nfsd_get_nrthreads(int n, int *nthreads)
{
	int i = 0;

	if (nfsd_serv != NULL) {
		for (i = 0; i < nfsd_serv->sv_nrpools && i < n; i++)
			nthreads[i] = nfsd_serv->sv_pools[i].sp_nrthreads;
	}

	return 0;
}

int nfsd_set_nrthreads(int n, int *nthreads)
{
	int i = 0;
	int tot = 0;
	int err = 0;

	if (nfsd_serv == NULL || n <= 0)
		return 0;

	if (n > nfsd_serv->sv_nrpools)
		n = nfsd_serv->sv_nrpools;

	/* enforce a global maximum number of threads */
	tot = 0;
	for (i = 0; i < n; i++) {
		if (nthreads[i] > NFSD_MAXSERVS)
			nthreads[i] = NFSD_MAXSERVS;
		tot += nthreads[i];
	}
	if (tot > NFSD_MAXSERVS) {
		/* total too large: scale down requested numbers */
		for (i = 0; i < n && tot > 0; i++) {
		    	int new = nthreads[i] * NFSD_MAXSERVS / tot;
			tot -= (nthreads[i] - new);
			nthreads[i] = new;
		}
		for (i = 0; i < n && tot > 0; i++) {
			nthreads[i]--;
			tot--;
		}
	}

	/*
	 * There must always be a thread in pool 0; the admin
	 * can't shut down NFS completely using pool_threads.
	 */
	if (nthreads[0] == 0)
		nthreads[0] = 1;

	/* apply the new numbers */
	lock_kernel();
	svc_get(nfsd_serv);
	for (i = 0; i < n; i++) {
		err = svc_set_num_threads(nfsd_serv, &nfsd_serv->sv_pools[i],
				    	  nthreads[i]);
		if (err)
			break;
	}
	svc_destroy(nfsd_serv);
	unlock_kernel();

	return err;
}

int
nfsd_svc(unsigned short port, int nrservs)
{
	int	error;
	
	lock_kernel();
	dprintk("nfsd: creating service\n");
	error = -EINVAL;
	if (nrservs <= 0)
		nrservs = 0;
	if (nrservs > NFSD_MAXSERVS)
		nrservs = NFSD_MAXSERVS;
	
	/* Readahead param cache - will no-op if it already exists */
	error =	nfsd_racache_init(2*nrservs);
	if (error<0)
		goto out;
	nfs4_state_start();

	nfsd_reset_versions();

	error = nfsd_create_serv();

	if (error)
		goto out;
	error = nfsd_init_socks(port);
	if (error)
		goto failure;

	error = svc_set_num_threads(nfsd_serv, NULL, nrservs);
 failure:
	svc_destroy(nfsd_serv);		/* Release server */
 out:
	unlock_kernel();
	return error;
}

static inline void
update_thread_usage(int busy_threads)
{
	unsigned long prev_call;
	unsigned long diff;
	int decile;

	spin_lock(&nfsd_call_lock);
	prev_call = nfsd_last_call;
	nfsd_last_call = jiffies;
	decile = busy_threads*10/nfsdstats.th_cnt;
	if (decile>0 && decile <= 10) {
		diff = nfsd_last_call - prev_call;
		if ( (nfsdstats.th_usage[decile-1] += diff) >= NFSD_USAGE_WRAP)
			nfsdstats.th_usage[decile-1] -= NFSD_USAGE_WRAP;
		if (decile == 10)
			nfsdstats.th_fullcnt++;
	}
	spin_unlock(&nfsd_call_lock);
}

/*
 * This is the NFS server kernel thread
 */
static void
nfsd(struct svc_rqst *rqstp)
{
	struct fs_struct *fsp;
	int		err;
	sigset_t shutdown_mask, allowed_mask;

	/* Lock module and set up kernel thread */
	lock_kernel();
	daemonize("nfsd");

	/* After daemonize() this kernel thread shares current->fs
	 * with the init process. We need to create files with a
	 * umask of 0 instead of init's umask. */
	fsp = copy_fs_struct(current->fs);
	if (!fsp) {
		printk("Unable to start nfsd thread: out of memory\n");
		goto out;
	}
	exit_fs(current);
	current->fs = fsp;
	current->fs->umask = 0;

	siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS);
	siginitsetinv(&allowed_mask, ALLOWED_SIGS);

	nfsdstats.th_cnt++;

	rqstp->rq_task = current;

	unlock_kernel();

	/*
	 * We want less throttling in balance_dirty_pages() so that nfs to
	 * localhost doesn't cause nfsd to lock up due to all the client's
	 * dirty pages.
	 */
	current->flags |= PF_LESS_THROTTLE;
	set_freezable();

	/*
	 * The main request loop
	 */
	for (;;) {
		/* Block all but the shutdown signals */
		sigprocmask(SIG_SETMASK, &shutdown_mask, NULL);

		/*
		 * Find a socket with data available and call its
		 * recvfrom routine.
		 */
		while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
			;
		if (err < 0)
			break;
		update_thread_usage(atomic_read(&nfsd_busy));
		atomic_inc(&nfsd_busy);

		/* Lock the export hash tables for reading. */
		exp_readlock();

		/* Process request with signals blocked.  */
		sigprocmask(SIG_SETMASK, &allowed_mask, NULL);

		svc_process(rqstp);

		/* Unlock export hash tables */
		exp_readunlock();
		update_thread_usage(atomic_read(&nfsd_busy));
		atomic_dec(&nfsd_busy);
	}

	if (err != -EINTR) {
		printk(KERN_WARNING "nfsd: terminating on error %d\n", -err);
	} else {
		unsigned int	signo;

		for (signo = 1; signo <= _NSIG; signo++)
			if (sigismember(&current->pending.signal, signo) &&
			    !sigismember(&current->blocked, signo))
				break;
		killsig = signo;
	}
	/* Clear signals before calling svc_exit_thread() */
	flush_signals(current);

	lock_kernel();

	nfsdstats.th_cnt --;

out:
	/* Release the thread */
	svc_exit_thread(rqstp);

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

static __be32 map_new_errors(u32 vers, __be32 nfserr)
{
	if (nfserr == nfserr_jukebox && vers == 2)
		return nfserr_dropit;
	if (nfserr == nfserr_wrongsec && vers < 4)
		return nfserr_acces;
	return nfserr;
}

int
nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
{
	struct svc_procedure	*proc;
	kxdrproc_t		xdr;
	__be32			nfserr;
	__be32			*nfserrp;

	dprintk("nfsd_dispatch: vers %d proc %d\n",
				rqstp->rq_vers, rqstp->rq_proc);
	proc = rqstp->rq_procinfo;

	/* Check whether we have this call in the cache. */
	switch (nfsd_cache_lookup(rqstp, proc->pc_cachetype)) {
	case RC_INTR:
	case RC_DROPIT:
		return 0;
	case RC_REPLY:
		return 1;
	case RC_DOIT:;
		/* do it */
	}

	/* Decode arguments */
	xdr = proc->pc_decode;
	if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base,
			rqstp->rq_argp)) {
		dprintk("nfsd: failed to decode arguments!\n");
		nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
		*statp = rpc_garbage_args;
		return 1;
	}

	/* need to grab the location to store the status, as
	 * nfsv4 does some encoding while processing 
	 */
	nfserrp = rqstp->rq_res.head[0].iov_base
		+ rqstp->rq_res.head[0].iov_len;
	rqstp->rq_res.head[0].iov_len += sizeof(__be32);

	/* Now call the procedure handler, and encode NFS status. */
	nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
	nfserr = map_new_errors(rqstp->rq_vers, nfserr);
	if (nfserr == nfserr_dropit) {
		dprintk("nfsd: Dropping request; may be revisited later\n");
		nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
		return 0;
	}

	if (rqstp->rq_proc != 0)
		*nfserrp++ = nfserr;

	/* Encode result.
	 * For NFSv2, additional info is never returned in case of an error.
	 */
	if (!(nfserr && rqstp->rq_vers == 2)) {
		xdr = proc->pc_encode;
		if (xdr && !xdr(rqstp, nfserrp,
				rqstp->rq_resp)) {
			/* Failed to encode result. Release cache entry */
			dprintk("nfsd: failed to encode result!\n");
			nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
			*statp = rpc_system_err;
			return 1;
		}
	}

	/* Store reply in cache. */
	nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1);
	return 1;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/nfsd/nfssvc.c
	3	*
	4	* Central processing for nfsd.
	5	*
	6	* Authors: Olaf Kirch (okir@monad.swb.de)
	7	*
	8	* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
	9	*/
	10
1da177e4	11	#include <linux/module.h>
e8edc6e0	12	#include <linux/sched.h>
1da177e4 LT	13	#include <linux/time.h>
	14	#include <linux/errno.h>
	15	#include <linux/nfs.h>
	16	#include <linux/in.h>
	17	#include <linux/uio.h>
	18	#include <linux/unistd.h>
	19	#include <linux/slab.h>
	20	#include <linux/smp.h>
	21	#include <linux/smp_lock.h>
83144186	22	#include <linux/freezer.h>
1da177e4 LT	23	#include <linux/fs_struct.h>
	24
	25	#include <linux/sunrpc/types.h>
	26	#include <linux/sunrpc/stats.h>
	27	#include <linux/sunrpc/svc.h>
	28	#include <linux/sunrpc/svcsock.h>
	29	#include <linux/sunrpc/cache.h>
	30	#include <linux/nfsd/nfsd.h>
	31	#include <linux/nfsd/stats.h>
	32	#include <linux/nfsd/cache.h>
70c3b76c	33	#include <linux/nfsd/syscall.h>
1da177e4	34	#include <linux/lockd/bind.h>
a257cdd0	35	#include <linux/nfsacl.h>
1da177e4 LT	36
	37	#define NFSDDBG_FACILITY NFSDDBG_SVC
	38
	39	/* these signals will be delivered to an nfsd thread
	40	* when handling a request
	41	*/
	42	#define ALLOWED_SIGS (sigmask(SIGKILL))
	43	/* these signals will be delivered to an nfsd thread
	44	* when not handling a request. i.e. when waiting
	45	*/
	46	#define SHUTDOWN_SIGS (sigmask(SIGKILL) \| sigmask(SIGHUP) \| sigmask(SIGINT) \| sigmask(SIGQUIT))
	47	/* if the last thread dies with SIGHUP, then the exports table is
	48	* left unchanged ( like 2.4-{0-9} ). Any other signal will clear
	49	* the exports table (like 2.2).
	50	*/
	51	#define SIG_NOCLEAN SIGHUP
	52
	53	extern struct svc_program nfsd_program;
	54	static void nfsd(struct svc_rqst *rqstp);
	55	struct timeval nfssvc_boot;
70c3b76c	56	struct svc_serv *nfsd_serv;
1da177e4 LT	57	static atomic_t nfsd_busy;
	58	static unsigned long nfsd_last_call;
	59	static DEFINE_SPINLOCK(nfsd_call_lock);
	60
3fb803a9 AG	61	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
	62	static struct svc_stat nfsd_acl_svcstats;
	63	static struct svc_version * nfsd_acl_version[] = {
	64	[2] = &nfsd_acl_version2,
	65	[3] = &nfsd_acl_version3,
	66	};
	67
	68	#define NFSD_ACL_MINVERS 2
e8c96f8c	69	#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
3fb803a9 AG	70	static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];
	71
	72	static struct svc_program nfsd_acl_program = {
	73	.pg_prog = NFS_ACL_PROGRAM,
	74	.pg_nvers = NFSD_ACL_NRVERS,
	75	.pg_vers = nfsd_acl_versions,
1a8eff6d	76	.pg_name = "nfsacl",
3fb803a9 AG	77	.pg_class = "nfsd",
	78	.pg_stats = &nfsd_acl_svcstats,
	79	.pg_authenticate = &svc_set_client,
	80	};
	81
	82	static struct svc_stat nfsd_acl_svcstats = {
	83	.program = &nfsd_acl_program,
	84	};
	85	#endif /* defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL) */
	86
70c3b76c N	87	static struct svc_version * nfsd_version[] = {
	88	[2] = &nfsd_version2,
	89	#if defined(CONFIG_NFSD_V3)
	90	[3] = &nfsd_version3,
	91	#endif
	92	#if defined(CONFIG_NFSD_V4)
	93	[4] = &nfsd_version4,
	94	#endif
	95	};
	96
	97	#define NFSD_MINVERS 2
e8c96f8c	98	#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
70c3b76c N	99	static struct svc_version *nfsd_versions[NFSD_NRVERS];
	100
	101	struct svc_program nfsd_program = {
3fb803a9 AG	102	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
	103	.pg_next = &nfsd_acl_program,
	104	#endif
70c3b76c N	105	.pg_prog = NFS_PROGRAM, /* program number */
	106	.pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
	107	.pg_vers = nfsd_versions, /* version table */
	108	.pg_name = "nfsd", /* program name */
	109	.pg_class = "nfsd", /* authentication class */
	110	.pg_stats = &nfsd_svcstats, /* version table */
	111	.pg_authenticate = &svc_set_client, /* export authentication */
	112
	113	};
	114
6658d3a7 N	115	int nfsd_vers(int vers, enum vers_op change)
	116	{
	117	if (vers < NFSD_MINVERS \|\| vers >= NFSD_NRVERS)
	118	return -1;
	119	switch(change) {
	120	case NFSD_SET:
	121	nfsd_versions[vers] = nfsd_version[vers];
6658d3a7 N	122	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
6658d3a7 N	123	if (vers < NFSD_ACL_NRVERS)
1a8eff6d	124	nfsd_acl_versions[vers] = nfsd_acl_version[vers];
6658d3a7	125	#endif
1a8eff6d	126	break;
6658d3a7 N	127	case NFSD_CLEAR:
	128	nfsd_versions[vers] = NULL;
	129	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
	130	if (vers < NFSD_ACL_NRVERS)
1a8eff6d	131	nfsd_acl_versions[vers] = NULL;
6658d3a7 N	132	#endif
	133	break;
	134	case NFSD_TEST:
	135	return nfsd_versions[vers] != NULL;
	136	case NFSD_AVAIL:
	137	return nfsd_version[vers] != NULL;
	138	}
	139	return 0;
	140	}
1da177e4 LT	141	/*
	142	* Maximum number of nfsd processes
	143	*/
	144	#define NFSD_MAXSERVS 8192
	145
	146	int nfsd_nrthreads(void)
	147	{
	148	if (nfsd_serv == NULL)
	149	return 0;
	150	else
	151	return nfsd_serv->sv_nrthreads;
	152	}
	153
bc591ccf N	154	static int killsig; /* signal that was used to kill last nfsd */
	155	static void nfsd_last_thread(struct svc_serv *serv)
	156	{
	157	/* When last nfsd thread exits we need to do some clean-up */
24e36663 N	158	struct svc_sock *svsk;
	159	list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
	160	lockd_down();
bc591ccf N	161	nfsd_serv = NULL;
	162	nfsd_racache_shutdown();
	163	nfs4_state_shutdown();
	164
	165	printk(KERN_WARNING "nfsd: last server has exited\n");
	166	if (killsig != SIG_NOCLEAN) {
	167	printk(KERN_WARNING "nfsd: unexporting all filesystems\n");
	168	nfsd_export_flush();
	169	}
	170	}
6658d3a7 N	171
	172	void nfsd_reset_versions(void)
	173	{
	174	int found_one = 0;
	175	int i;
	176
	177	for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
	178	if (nfsd_program.pg_vers[i])
	179	found_one = 1;
	180	}
	181
	182	if (!found_one) {
	183	for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
	184	nfsd_program.pg_vers[i] = nfsd_version[i];
	185	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
	186	for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
	187	nfsd_acl_program.pg_vers[i] =
	188	nfsd_acl_version[i];
	189	#endif
	190	}
	191	}
	192
b41b66d6	193	int nfsd_create_serv(void)
02a375f0 N	194	{
	195	int err = 0;
	196	lock_kernel();
	197	if (nfsd_serv) {
9a24ab57	198	svc_get(nfsd_serv);
02a375f0 N	199	unlock_kernel();
	200	return 0;
	201	}
596bbe53 N	202	if (nfsd_max_blksize == 0) {
	203	/* choose a suitable default */
	204	struct sysinfo i;
	205	si_meminfo(&i);
	206	/* Aim for 1/4096 of memory per thread
	207	* This gives 1MB on 4Gig machines
	208	* But only uses 32K on 128M machines.
	209	* Bottom out at 8K on 32M and smaller.
	210	* Of course, this is only a default.
	211	*/
	212	nfsd_max_blksize = NFSSVC_MAXBLKSIZE;
44c55600	213	i.totalram <<= PAGE_SHIFT - 12;
596bbe53 N	214	while (nfsd_max_blksize > i.totalram &&
	215	nfsd_max_blksize >= 810242)
	216	nfsd_max_blksize /= 2;
	217	}
02a375f0 N	218
02a375f0 N	219	atomic_set(&nfsd_busy, 0);
596bbe53	220	nfsd_serv = svc_create_pooled(&nfsd_program,
c6b0a9f8	221	nfsd_max_blksize,
eec09661 GB	222	nfsd_last_thread,
eec09661 GB	223	nfsd, SIG_NOCLEAN, THIS_MODULE);
02a375f0 N	224	if (nfsd_serv == NULL)
02a375f0 N	225	err = -ENOMEM;
02a375f0 N	226	unlock_kernel();
	227	do_gettimeofday(&nfssvc_boot); /* record boot time */
	228	return err;
	229	}
	230
	231	static int nfsd_init_socks(int port)
	232	{
	233	int error;
	234	if (!list_empty(&nfsd_serv->sv_permsocks))
	235	return 0;
	236
02a375f0	237	error = lockd_up(IPPROTO_UDP);
4a3ae42d	238	if (error >= 0) {
482fb94e CL	239	error = svc_makesock(nfsd_serv, IPPROTO_UDP, port,
482fb94e CL	240	SVC_SOCK_DEFAULTS);
4a3ae42d N	241	if (error < 0)
	242	lockd_down();
	243	}
02a375f0 N	244	if (error < 0)
	245	return error;
	246
	247	#ifdef CONFIG_NFSD_TCP
02a375f0	248	error = lockd_up(IPPROTO_TCP);
4a3ae42d	249	if (error >= 0) {
482fb94e CL	250	error = svc_makesock(nfsd_serv, IPPROTO_TCP, port,
482fb94e CL	251	SVC_SOCK_DEFAULTS);
4a3ae42d N	252	if (error < 0)
	253	lockd_down();
	254	}
02a375f0 N	255	if (error < 0)
	256	return error;
	257	#endif
	258	return 0;
	259	}
	260
eed2965a GB	261	int nfsd_nrpools(void)
	262	{
	263	if (nfsd_serv == NULL)
	264	return 0;
	265	else
	266	return nfsd_serv->sv_nrpools;
	267	}
	268
	269	int nfsd_get_nrthreads(int n, int *nthreads)
	270	{
	271	int i = 0;
	272
	273	if (nfsd_serv != NULL) {
	274	for (i = 0; i < nfsd_serv->sv_nrpools && i < n; i++)
	275	nthreads[i] = nfsd_serv->sv_pools[i].sp_nrthreads;
	276	}
	277
	278	return 0;
	279	}
	280
	281	int nfsd_set_nrthreads(int n, int *nthreads)
	282	{
	283	int i = 0;
	284	int tot = 0;
	285	int err = 0;
	286
	287	if (nfsd_serv == NULL \|\| n <= 0)
	288	return 0;
	289
	290	if (n > nfsd_serv->sv_nrpools)
	291	n = nfsd_serv->sv_nrpools;
	292
	293	/* enforce a global maximum number of threads */
	294	tot = 0;
	295	for (i = 0; i < n; i++) {
	296	if (nthreads[i] > NFSD_MAXSERVS)
	297	nthreads[i] = NFSD_MAXSERVS;
	298	tot += nthreads[i];
	299	}
	300	if (tot > NFSD_MAXSERVS) {
	301	/* total too large: scale down requested numbers */
	302	for (i = 0; i < n && tot > 0; i++) {
	303	int new = nthreads[i] * NFSD_MAXSERVS / tot;
	304	tot -= (nthreads[i] - new);
	305	nthreads[i] = new;
	306	}
	307	for (i = 0; i < n && tot > 0; i++) {
	308	nthreads[i]--;
	309	tot--;
	310	}
	311	}
	312
	313	/*
	314	* There must always be a thread in pool 0; the admin
	315	* can't shut down NFS completely using pool_threads.
	316	*/
	317	if (nthreads[0] == 0)
	318	nthreads[0] = 1;
	319
	320	/* apply the new numbers */
	321	lock_kernel();
	322	svc_get(nfsd_serv);
	323	for (i = 0; i < n; i++) {
	324	err = svc_set_num_threads(nfsd_serv, &nfsd_serv->sv_pools[i],
325	nthreads[i]);
326	if (err)
327	break;
328	}
329	svc_destroy(nfsd_serv);
330	unlock_kernel();
331
332	return err;
333	}
334
1da177e4 LT	335	int
	336	nfsd_svc(unsigned short port, int nrservs)
	337	{
	338	int error;
1da177e4 LT	339
1da177e4 LT	340	lock_kernel();
6658d3a7	341	dprintk("nfsd: creating service\n");
1da177e4 LT	342	error = -EINVAL;
	343	if (nrservs <= 0)
	344	nrservs = 0;
	345	if (nrservs > NFSD_MAXSERVS)
	346	nrservs = NFSD_MAXSERVS;
	347
	348	/* Readahead param cache - will no-op if it already exists */
	349	error = nfsd_racache_init(2*nrservs);
	350	if (error<0)
	351	goto out;
e8ff2a84	352	nfs4_state_start();
02a375f0 N	353
	354	nfsd_reset_versions();
	355
	356	error = nfsd_create_serv();
	357
	358	if (error)
	359	goto out;
	360	error = nfsd_init_socks(port);
	361	if (error)
	362	goto failure;
	363
eec09661	364	error = svc_set_num_threads(nfsd_serv, NULL, nrservs);
1da177e4	365	failure:
1da177e4	366	svc_destroy(nfsd_serv); /* Release server */
1da177e4 LT	367	out:
	368	unlock_kernel();
	369	return error;
	370	}
	371
	372	static inline void
	373	update_thread_usage(int busy_threads)
	374	{
	375	unsigned long prev_call;
	376	unsigned long diff;
	377	int decile;
	378
	379	spin_lock(&nfsd_call_lock);
	380	prev_call = nfsd_last_call;
	381	nfsd_last_call = jiffies;
	382	decile = busy_threads*10/nfsdstats.th_cnt;
	383	if (decile>0 && decile <= 10) {
	384	diff = nfsd_last_call - prev_call;
	385	if ( (nfsdstats.th_usage[decile-1] += diff) >= NFSD_USAGE_WRAP)
	386	nfsdstats.th_usage[decile-1] -= NFSD_USAGE_WRAP;
	387	if (decile == 10)
	388	nfsdstats.th_fullcnt++;
	389	}
	390	spin_unlock(&nfsd_call_lock);
	391	}
	392
	393	/*
	394	* This is the NFS server kernel thread
	395	*/
	396	static void
	397	nfsd(struct svc_rqst *rqstp)
	398	{
1da177e4 LT	399	struct fs_struct *fsp;
1da177e4 LT	400	int err;
1da177e4 LT	401	sigset_t shutdown_mask, allowed_mask;
	402
	403	/* Lock module and set up kernel thread */
	404	lock_kernel();
	405	daemonize("nfsd");
	406
	407	/* After daemonize() this kernel thread shares current->fs
	408	* with the init process. We need to create files with a
	409	* umask of 0 instead of init's umask. */
	410	fsp = copy_fs_struct(current->fs);
	411	if (!fsp) {
	412	printk("Unable to start nfsd thread: out of memory\n");
	413	goto out;
	414	}
	415	exit_fs(current);
	416	current->fs = fsp;
	417	current->fs->umask = 0;
	418
	419	siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS);
	420	siginitsetinv(&allowed_mask, ALLOWED_SIGS);
	421
	422	nfsdstats.th_cnt++;
	423
eec09661	424	rqstp->rq_task = current;
1da177e4 LT	425
	426	unlock_kernel();
	427
	428	/*
	429	* We want less throttling in balance_dirty_pages() so that nfs to
	430	* localhost doesn't cause nfsd to lock up due to all the client's
	431	* dirty pages.
	432	*/
	433	current->flags \|= PF_LESS_THROTTLE;
83144186	434	set_freezable();
1da177e4 LT	435
	436	/*
	437	* The main request loop
	438	*/
	439	for (;;) {
	440	/* Block all but the shutdown signals */
	441	sigprocmask(SIG_SETMASK, &shutdown_mask, NULL);
	442
	443	/*
	444	* Find a socket with data available and call its
	445	* recvfrom routine.
	446	*/
6fb2b47f	447	while ((err = svc_recv(rqstp, 6060HZ)) == -EAGAIN)
1da177e4 LT	448	;
	449	if (err < 0)
	450	break;
	451	update_thread_usage(atomic_read(&nfsd_busy));
	452	atomic_inc(&nfsd_busy);
	453
	454	/* Lock the export hash tables for reading. */
	455	exp_readlock();
	456
	457	/* Process request with signals blocked. */
	458	sigprocmask(SIG_SETMASK, &allowed_mask, NULL);
	459
6fb2b47f	460	svc_process(rqstp);
1da177e4 LT	461
	462	/* Unlock export hash tables */
	463	exp_readunlock();
	464	update_thread_usage(atomic_read(&nfsd_busy));
	465	atomic_dec(&nfsd_busy);
	466	}
	467
	468	if (err != -EINTR) {
	469	printk(KERN_WARNING "nfsd: terminating on error %d\n", -err);
	470	} else {
	471	unsigned int signo;
	472
	473	for (signo = 1; signo <= _NSIG; signo++)
	474	if (sigismember(&current->pending.signal, signo) &&
	475	!sigismember(&current->blocked, signo))
	476	break;
bc591ccf	477	killsig = signo;
1da177e4	478	}
24e36663	479	/* Clear signals before calling svc_exit_thread() */
9e416052	480	flush_signals(current);
1da177e4 LT	481
	482	lock_kernel();
	483
1da177e4 LT	484	nfsdstats.th_cnt --;
	485
	486	out:
	487	/* Release the thread */
	488	svc_exit_thread(rqstp);
	489
	490	/* Release module */
c4f92dba	491	unlock_kernel();
1da177e4 LT	492	module_put_and_exit(0);
	493	}
	494
32c1eb0c AA	495	static __be32 map_new_errors(u32 vers, __be32 nfserr)
	496	{
	497	if (nfserr == nfserr_jukebox && vers == 2)
	498	return nfserr_dropit;
	499	if (nfserr == nfserr_wrongsec && vers < 4)
	500	return nfserr_acces;
	501	return nfserr;
	502	}
	503
1da177e4	504	int
c7afef1f	505	nfsd_dispatch(struct svc_rqst rqstp, __be32 statp)
1da177e4 LT	506	{
	507	struct svc_procedure *proc;
	508	kxdrproc_t xdr;
ad451d38 AV	509	__be32 nfserr;
ad451d38 AV	510	__be32 *nfserrp;
1da177e4 LT	511
	512	dprintk("nfsd_dispatch: vers %d proc %d\n",
	513	rqstp->rq_vers, rqstp->rq_proc);
	514	proc = rqstp->rq_procinfo;
	515
	516	/* Check whether we have this call in the cache. */
	517	switch (nfsd_cache_lookup(rqstp, proc->pc_cachetype)) {
	518	case RC_INTR:
	519	case RC_DROPIT:
	520	return 0;
	521	case RC_REPLY:
	522	return 1;
	523	case RC_DOIT:;
	524	/* do it */
	525	}
	526
	527	/* Decode arguments */
	528	xdr = proc->pc_decode;
ad451d38	529	if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base,
1da177e4 LT	530	rqstp->rq_argp)) {
	531	dprintk("nfsd: failed to decode arguments!\n");
	532	nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
	533	*statp = rpc_garbage_args;
	534	return 1;
	535	}
	536
	537	/* need to grab the location to store the status, as
	538	* nfsv4 does some encoding while processing
	539	*/
	540	nfserrp = rqstp->rq_res.head[0].iov_base
	541	+ rqstp->rq_res.head[0].iov_len;
ad451d38	542	rqstp->rq_res.head[0].iov_len += sizeof(__be32);
1da177e4 LT	543
	544	/* Now call the procedure handler, and encode NFS status. */
	545	nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
32c1eb0c	546	nfserr = map_new_errors(rqstp->rq_vers, nfserr);
1da177e4	547	if (nfserr == nfserr_dropit) {
45457e09	548	dprintk("nfsd: Dropping request; may be revisited later\n");
1da177e4 LT	549	nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
	550	return 0;
	551	}
	552
	553	if (rqstp->rq_proc != 0)
	554	*nfserrp++ = nfserr;
	555
	556	/* Encode result.
	557	* For NFSv2, additional info is never returned in case of an error.
	558	*/
	559	if (!(nfserr && rqstp->rq_vers == 2)) {
	560	xdr = proc->pc_encode;
	561	if (xdr && !xdr(rqstp, nfserrp,
	562	rqstp->rq_resp)) {
	563	/* Failed to encode result. Release cache entry */
	564	dprintk("nfsd: failed to encode result!\n");
	565	nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
	566	*statp = rpc_system_err;
	567	return 1;
	568	}
	569	}
	570
	571	/* Store reply in cache. */
	572	nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1);
	573	return 1;
	574	}