[linux.git] / fs / nfsd / nfssvc.c

/*
 * linux/fs/nfsd/nfssvc.c
 *
 * Central processing for nfsd.
 *
 * Authors:	Olaf Kirch ([email protected])
 *
 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <[email protected]>
 */

#include <linux/module.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/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;
	error = nfs4_state_start();
	if (error<0)
		goto out;

	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;

	/*
	 * 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);
}

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);
	if (nfserr == nfserr_jukebox && rqstp->rq_vers == 2)
		nfserr = nfserr_dropit;
	if (nfserr == nfserr_dropit) {
		dprintk("nfsd: Dropping request due to malloc failure!\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 ([email protected])
	7	*
	8	* Copyright (C) 1995, 1996, 1997 Olaf Kirch <[email protected]>
	9	*/
	10
1da177e4 LT	11	#include <linux/module.h>
	12
	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>
	22	#include <linux/fs_struct.h>
	23
	24	#include <linux/sunrpc/types.h>
	25	#include <linux/sunrpc/stats.h>
	26	#include <linux/sunrpc/svc.h>
	27	#include <linux/sunrpc/svcsock.h>
	28	#include <linux/sunrpc/cache.h>
	29	#include <linux/nfsd/nfsd.h>
	30	#include <linux/nfsd/stats.h>
	31	#include <linux/nfsd/cache.h>
70c3b76c	32	#include <linux/nfsd/syscall.h>
1da177e4	33	#include <linux/lockd/bind.h>
a257cdd0	34	#include <linux/nfsacl.h>
1da177e4 LT	35
	36	#define NFSDDBG_FACILITY NFSDDBG_SVC
	37
	38	/* these signals will be delivered to an nfsd thread
	39	* when handling a request
	40	*/
	41	#define ALLOWED_SIGS (sigmask(SIGKILL))
	42	/* these signals will be delivered to an nfsd thread
	43	* when not handling a request. i.e. when waiting
	44	*/
	45	#define SHUTDOWN_SIGS (sigmask(SIGKILL) \| sigmask(SIGHUP) \| sigmask(SIGINT) \| sigmask(SIGQUIT))
	46	/* if the last thread dies with SIGHUP, then the exports table is
	47	* left unchanged ( like 2.4-{0-9} ). Any other signal will clear
	48	* the exports table (like 2.2).
	49	*/
	50	#define SIG_NOCLEAN SIGHUP
	51
	52	extern struct svc_program nfsd_program;
	53	static void nfsd(struct svc_rqst *rqstp);
	54	struct timeval nfssvc_boot;
70c3b76c	55	struct svc_serv *nfsd_serv;
1da177e4 LT	56	static atomic_t nfsd_busy;
	57	static unsigned long nfsd_last_call;
	58	static DEFINE_SPINLOCK(nfsd_call_lock);
	59
3fb803a9 AG	60	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
	61	static struct svc_stat nfsd_acl_svcstats;
	62	static struct svc_version * nfsd_acl_version[] = {
	63	[2] = &nfsd_acl_version2,
	64	[3] = &nfsd_acl_version3,
	65	};
	66
	67	#define NFSD_ACL_MINVERS 2
e8c96f8c	68	#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
3fb803a9 AG	69	static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];
	70
	71	static struct svc_program nfsd_acl_program = {
	72	.pg_prog = NFS_ACL_PROGRAM,
	73	.pg_nvers = NFSD_ACL_NRVERS,
	74	.pg_vers = nfsd_acl_versions,
1a8eff6d	75	.pg_name = "nfsacl",
3fb803a9 AG	76	.pg_class = "nfsd",
	77	.pg_stats = &nfsd_acl_svcstats,
	78	.pg_authenticate = &svc_set_client,
	79	};
	80
	81	static struct svc_stat nfsd_acl_svcstats = {
	82	.program = &nfsd_acl_program,
	83	};
	84	#endif /* defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL) */
	85
70c3b76c N	86	static struct svc_version * nfsd_version[] = {
	87	[2] = &nfsd_version2,
	88	#if defined(CONFIG_NFSD_V3)
	89	[3] = &nfsd_version3,
	90	#endif
	91	#if defined(CONFIG_NFSD_V4)
	92	[4] = &nfsd_version4,
	93	#endif
	94	};
	95
	96	#define NFSD_MINVERS 2
e8c96f8c	97	#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
70c3b76c N	98	static struct svc_version *nfsd_versions[NFSD_NRVERS];
	99
	100	struct svc_program nfsd_program = {
3fb803a9 AG	101	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
	102	.pg_next = &nfsd_acl_program,
	103	#endif
70c3b76c N	104	.pg_prog = NFS_PROGRAM, /* program number */
	105	.pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
	106	.pg_vers = nfsd_versions, /* version table */
	107	.pg_name = "nfsd", /* program name */
	108	.pg_class = "nfsd", /* authentication class */
	109	.pg_stats = &nfsd_svcstats, /* version table */
	110	.pg_authenticate = &svc_set_client, /* export authentication */
	111
	112	};
	113
6658d3a7 N	114	int nfsd_vers(int vers, enum vers_op change)
	115	{
	116	if (vers < NFSD_MINVERS \|\| vers >= NFSD_NRVERS)
	117	return -1;
	118	switch(change) {
	119	case NFSD_SET:
	120	nfsd_versions[vers] = nfsd_version[vers];
6658d3a7 N	121	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
6658d3a7 N	122	if (vers < NFSD_ACL_NRVERS)
1a8eff6d	123	nfsd_acl_versions[vers] = nfsd_acl_version[vers];
6658d3a7	124	#endif
1a8eff6d	125	break;
6658d3a7 N	126	case NFSD_CLEAR:
	127	nfsd_versions[vers] = NULL;
	128	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
	129	if (vers < NFSD_ACL_NRVERS)
1a8eff6d	130	nfsd_acl_versions[vers] = NULL;
6658d3a7 N	131	#endif
	132	break;
	133	case NFSD_TEST:
	134	return nfsd_versions[vers] != NULL;
	135	case NFSD_AVAIL:
	136	return nfsd_version[vers] != NULL;
	137	}
	138	return 0;
	139	}
1da177e4 LT	140	/*
	141	* Maximum number of nfsd processes
	142	*/
	143	#define NFSD_MAXSERVS 8192
	144
	145	int nfsd_nrthreads(void)
	146	{
	147	if (nfsd_serv == NULL)
	148	return 0;
	149	else
	150	return nfsd_serv->sv_nrthreads;
	151	}
	152
bc591ccf N	153	static int killsig; /* signal that was used to kill last nfsd */
	154	static void nfsd_last_thread(struct svc_serv *serv)
	155	{
	156	/* When last nfsd thread exits we need to do some clean-up */
24e36663 N	157	struct svc_sock *svsk;
	158	list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
	159	lockd_down();
bc591ccf N	160	nfsd_serv = NULL;
	161	nfsd_racache_shutdown();
	162	nfs4_state_shutdown();
	163
	164	printk(KERN_WARNING "nfsd: last server has exited\n");
	165	if (killsig != SIG_NOCLEAN) {
	166	printk(KERN_WARNING "nfsd: unexporting all filesystems\n");
	167	nfsd_export_flush();
	168	}
	169	}
6658d3a7 N	170
	171	void nfsd_reset_versions(void)
	172	{
	173	int found_one = 0;
	174	int i;
	175
	176	for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
	177	if (nfsd_program.pg_vers[i])
	178	found_one = 1;
	179	}
	180
	181	if (!found_one) {
	182	for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
	183	nfsd_program.pg_vers[i] = nfsd_version[i];
	184	#if defined(CONFIG_NFSD_V2_ACL) \|\| defined(CONFIG_NFSD_V3_ACL)
	185	for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
	186	nfsd_acl_program.pg_vers[i] =
	187	nfsd_acl_version[i];
	188	#endif
	189	}
	190	}
	191
b41b66d6	192	int nfsd_create_serv(void)
02a375f0 N	193	{
	194	int err = 0;
	195	lock_kernel();
	196	if (nfsd_serv) {
9a24ab57	197	svc_get(nfsd_serv);
02a375f0 N	198	unlock_kernel();
	199	return 0;
	200	}
596bbe53 N	201	if (nfsd_max_blksize == 0) {
	202	/* choose a suitable default */
	203	struct sysinfo i;
	204	si_meminfo(&i);
	205	/* Aim for 1/4096 of memory per thread
	206	* This gives 1MB on 4Gig machines
	207	* But only uses 32K on 128M machines.
	208	* Bottom out at 8K on 32M and smaller.
	209	* Of course, this is only a default.
	210	*/
	211	nfsd_max_blksize = NFSSVC_MAXBLKSIZE;
44c55600	212	i.totalram <<= PAGE_SHIFT - 12;
596bbe53 N	213	while (nfsd_max_blksize > i.totalram &&
	214	nfsd_max_blksize >= 810242)
	215	nfsd_max_blksize /= 2;
	216	}
02a375f0 N	217
02a375f0 N	218	atomic_set(&nfsd_busy, 0);
596bbe53	219	nfsd_serv = svc_create_pooled(&nfsd_program,
c6b0a9f8	220	nfsd_max_blksize,
eec09661 GB	221	nfsd_last_thread,
eec09661 GB	222	nfsd, SIG_NOCLEAN, THIS_MODULE);
02a375f0 N	223	if (nfsd_serv == NULL)
02a375f0 N	224	err = -ENOMEM;
02a375f0 N	225	unlock_kernel();
	226	do_gettimeofday(&nfssvc_boot); /* record boot time */
	227	return err;
	228	}
	229
	230	static int nfsd_init_socks(int port)
	231	{
	232	int error;
	233	if (!list_empty(&nfsd_serv->sv_permsocks))
	234	return 0;
	235
02a375f0	236	error = lockd_up(IPPROTO_UDP);
4a3ae42d	237	if (error >= 0) {
482fb94e CL	238	error = svc_makesock(nfsd_serv, IPPROTO_UDP, port,
482fb94e CL	239	SVC_SOCK_DEFAULTS);
4a3ae42d N	240	if (error < 0)
	241	lockd_down();
	242	}
02a375f0 N	243	if (error < 0)
	244	return error;
	245
	246	#ifdef CONFIG_NFSD_TCP
02a375f0	247	error = lockd_up(IPPROTO_TCP);
4a3ae42d	248	if (error >= 0) {
482fb94e CL	249	error = svc_makesock(nfsd_serv, IPPROTO_TCP, port,
482fb94e CL	250	SVC_SOCK_DEFAULTS);
4a3ae42d N	251	if (error < 0)
	252	lockd_down();
	253	}
02a375f0 N	254	if (error < 0)
	255	return error;
	256	#endif
	257	return 0;
	258	}
	259
eed2965a GB	260	int nfsd_nrpools(void)
	261	{
	262	if (nfsd_serv == NULL)
	263	return 0;
	264	else
	265	return nfsd_serv->sv_nrpools;
	266	}
	267
	268	int nfsd_get_nrthreads(int n, int *nthreads)
	269	{
	270	int i = 0;
	271
	272	if (nfsd_serv != NULL) {
	273	for (i = 0; i < nfsd_serv->sv_nrpools && i < n; i++)
	274	nthreads[i] = nfsd_serv->sv_pools[i].sp_nrthreads;
	275	}
	276
	277	return 0;
	278	}
	279
	280	int nfsd_set_nrthreads(int n, int *nthreads)
	281	{
	282	int i = 0;
	283	int tot = 0;
	284	int err = 0;
	285
	286	if (nfsd_serv == NULL \|\| n <= 0)
	287	return 0;
	288
	289	if (n > nfsd_serv->sv_nrpools)
	290	n = nfsd_serv->sv_nrpools;
	291
	292	/* enforce a global maximum number of threads */
	293	tot = 0;
	294	for (i = 0; i < n; i++) {
	295	if (nthreads[i] > NFSD_MAXSERVS)
	296	nthreads[i] = NFSD_MAXSERVS;
	297	tot += nthreads[i];
	298	}
	299	if (tot > NFSD_MAXSERVS) {
	300	/* total too large: scale down requested numbers */
	301	for (i = 0; i < n && tot > 0; i++) {
	302	int new = nthreads[i] * NFSD_MAXSERVS / tot;
	303	tot -= (nthreads[i] - new);
	304	nthreads[i] = new;
	305	}
	306	for (i = 0; i < n && tot > 0; i++) {
	307	nthreads[i]--;
	308	tot--;
	309	}
	310	}
	311
	312	/*
	313	* There must always be a thread in pool 0; the admin
	314	* can't shut down NFS completely using pool_threads.
	315	*/
	316	if (nthreads[0] == 0)
	317	nthreads[0] = 1;
	318
	319	/* apply the new numbers */
	320	lock_kernel();
	321	svc_get(nfsd_serv);
	322	for (i = 0; i < n; i++) {
	323	err = svc_set_num_threads(nfsd_serv, &nfsd_serv->sv_pools[i],
324	nthreads[i]);
325	if (err)
326	break;
327	}
328	svc_destroy(nfsd_serv);
329	unlock_kernel();
330
331	return err;
332	}
333
1da177e4 LT	334	int
	335	nfsd_svc(unsigned short port, int nrservs)
	336	{
	337	int error;
1da177e4 LT	338
1da177e4 LT	339	lock_kernel();
6658d3a7	340	dprintk("nfsd: creating service\n");
1da177e4 LT	341	error = -EINVAL;
	342	if (nrservs <= 0)
	343	nrservs = 0;
	344	if (nrservs > NFSD_MAXSERVS)
	345	nrservs = NFSD_MAXSERVS;
	346
	347	/* Readahead param cache - will no-op if it already exists */
	348	error = nfsd_racache_init(2*nrservs);
	349	if (error<0)
	350	goto out;
76a3550e	351	error = nfs4_state_start();
1da177e4 LT	352	if (error<0)
1da177e4 LT	353	goto out;
02a375f0 N	354
	355	nfsd_reset_versions();
	356
	357	error = nfsd_create_serv();
	358
	359	if (error)
	360	goto out;
	361	error = nfsd_init_socks(port);
	362	if (error)
	363	goto failure;
	364
eec09661	365	error = svc_set_num_threads(nfsd_serv, NULL, nrservs);
1da177e4	366	failure:
1da177e4	367	svc_destroy(nfsd_serv); /* Release server */
1da177e4 LT	368	out:
	369	unlock_kernel();
	370	return error;
	371	}
	372
	373	static inline void
	374	update_thread_usage(int busy_threads)
	375	{
	376	unsigned long prev_call;
	377	unsigned long diff;
	378	int decile;
	379
	380	spin_lock(&nfsd_call_lock);
	381	prev_call = nfsd_last_call;
	382	nfsd_last_call = jiffies;
	383	decile = busy_threads*10/nfsdstats.th_cnt;
	384	if (decile>0 && decile <= 10) {
	385	diff = nfsd_last_call - prev_call;
	386	if ( (nfsdstats.th_usage[decile-1] += diff) >= NFSD_USAGE_WRAP)
	387	nfsdstats.th_usage[decile-1] -= NFSD_USAGE_WRAP;
	388	if (decile == 10)
	389	nfsdstats.th_fullcnt++;
	390	}
	391	spin_unlock(&nfsd_call_lock);
	392	}
	393
	394	/*
	395	* This is the NFS server kernel thread
	396	*/
	397	static void
	398	nfsd(struct svc_rqst *rqstp)
	399	{
1da177e4 LT	400	struct fs_struct *fsp;
1da177e4 LT	401	int err;
1da177e4 LT	402	sigset_t shutdown_mask, allowed_mask;
	403
	404	/* Lock module and set up kernel thread */
	405	lock_kernel();
	406	daemonize("nfsd");
	407
	408	/* After daemonize() this kernel thread shares current->fs
	409	* with the init process. We need to create files with a
	410	* umask of 0 instead of init's umask. */
	411	fsp = copy_fs_struct(current->fs);
	412	if (!fsp) {
	413	printk("Unable to start nfsd thread: out of memory\n");
	414	goto out;
	415	}
	416	exit_fs(current);
	417	current->fs = fsp;
	418	current->fs->umask = 0;
	419
	420	siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS);
	421	siginitsetinv(&allowed_mask, ALLOWED_SIGS);
	422
	423	nfsdstats.th_cnt++;
	424
eec09661	425	rqstp->rq_task = current;
1da177e4 LT	426
	427	unlock_kernel();
	428
	429	/*
	430	* We want less throttling in balance_dirty_pages() so that nfs to
	431	* localhost doesn't cause nfsd to lock up due to all the client's
	432	* dirty pages.
	433	*/
	434	current->flags \|= PF_LESS_THROTTLE;
	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
	495	int
c7afef1f	496	nfsd_dispatch(struct svc_rqst rqstp, __be32 statp)
1da177e4 LT	497	{
	498	struct svc_procedure *proc;
	499	kxdrproc_t xdr;
ad451d38 AV	500	__be32 nfserr;
ad451d38 AV	501	__be32 *nfserrp;
1da177e4 LT	502
	503	dprintk("nfsd_dispatch: vers %d proc %d\n",
	504	rqstp->rq_vers, rqstp->rq_proc);
	505	proc = rqstp->rq_procinfo;
	506
	507	/* Check whether we have this call in the cache. */
	508	switch (nfsd_cache_lookup(rqstp, proc->pc_cachetype)) {
	509	case RC_INTR:
	510	case RC_DROPIT:
	511	return 0;
	512	case RC_REPLY:
	513	return 1;
	514	case RC_DOIT:;
	515	/* do it */
	516	}
	517
	518	/* Decode arguments */
	519	xdr = proc->pc_decode;
ad451d38	520	if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base,
1da177e4 LT	521	rqstp->rq_argp)) {
	522	dprintk("nfsd: failed to decode arguments!\n");
	523	nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
	524	*statp = rpc_garbage_args;
	525	return 1;
	526	}
	527
	528	/* need to grab the location to store the status, as
	529	* nfsv4 does some encoding while processing
	530	*/
	531	nfserrp = rqstp->rq_res.head[0].iov_base
	532	+ rqstp->rq_res.head[0].iov_len;
ad451d38	533	rqstp->rq_res.head[0].iov_len += sizeof(__be32);
1da177e4 LT	534
	535	/* Now call the procedure handler, and encode NFS status. */
	536	nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
	537	if (nfserr == nfserr_jukebox && rqstp->rq_vers == 2)
	538	nfserr = nfserr_dropit;
	539	if (nfserr == nfserr_dropit) {
	540	dprintk("nfsd: Dropping request due to malloc failure!\n");
	541	nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
	542	return 0;
	543	}
	544
	545	if (rqstp->rq_proc != 0)
	546	*nfserrp++ = nfserr;
	547
	548	/* Encode result.
	549	* For NFSv2, additional info is never returned in case of an error.
	550	*/
	551	if (!(nfserr && rqstp->rq_vers == 2)) {
	552	xdr = proc->pc_encode;
	553	if (xdr && !xdr(rqstp, nfserrp,
	554	rqstp->rq_resp)) {
	555	/* Failed to encode result. Release cache entry */
	556	dprintk("nfsd: failed to encode result!\n");
	557	nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
	558	*statp = rpc_system_err;
	559	return 1;
	560	}
	561	}
	562
	563	/* Store reply in cache. */
	564	nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1);
	565	return 1;
	566	}