xref: /openbmc/linux/fs/nfsd/nfsctl.c (revision 22246614)
1 /*
2  * linux/fs/nfsd/nfsctl.c
3  *
4  * Syscall interface to knfsd.
5  *
6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
7  */
8 
9 #include <linux/module.h>
10 
11 #include <linux/linkage.h>
12 #include <linux/time.h>
13 #include <linux/errno.h>
14 #include <linux/fs.h>
15 #include <linux/fcntl.h>
16 #include <linux/net.h>
17 #include <linux/in.h>
18 #include <linux/syscalls.h>
19 #include <linux/unistd.h>
20 #include <linux/slab.h>
21 #include <linux/proc_fs.h>
22 #include <linux/seq_file.h>
23 #include <linux/pagemap.h>
24 #include <linux/init.h>
25 #include <linux/inet.h>
26 #include <linux/string.h>
27 #include <linux/smp_lock.h>
28 #include <linux/ctype.h>
29 
30 #include <linux/nfs.h>
31 #include <linux/nfsd_idmap.h>
32 #include <linux/lockd/bind.h>
33 #include <linux/sunrpc/svc.h>
34 #include <linux/sunrpc/svcsock.h>
35 #include <linux/nfsd/nfsd.h>
36 #include <linux/nfsd/cache.h>
37 #include <linux/nfsd/xdr.h>
38 #include <linux/nfsd/syscall.h>
39 #include <linux/lockd/lockd.h>
40 
41 #include <asm/uaccess.h>
42 #include <net/ipv6.h>
43 
44 /*
45  *	We have a single directory with 9 nodes in it.
46  */
47 enum {
48 	NFSD_Root = 1,
49 	NFSD_Svc,
50 	NFSD_Add,
51 	NFSD_Del,
52 	NFSD_Export,
53 	NFSD_Unexport,
54 	NFSD_Getfd,
55 	NFSD_Getfs,
56 	NFSD_List,
57 	NFSD_Fh,
58 	NFSD_FO_UnlockIP,
59 	NFSD_FO_UnlockFS,
60 	NFSD_Threads,
61 	NFSD_Pool_Threads,
62 	NFSD_Versions,
63 	NFSD_Ports,
64 	NFSD_MaxBlkSize,
65 	/*
66 	 * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
67 	 * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
68 	 */
69 #ifdef CONFIG_NFSD_V4
70 	NFSD_Leasetime,
71 	NFSD_RecoveryDir,
72 #endif
73 };
74 
75 /*
76  * write() for these nodes.
77  */
78 static ssize_t write_svc(struct file *file, char *buf, size_t size);
79 static ssize_t write_add(struct file *file, char *buf, size_t size);
80 static ssize_t write_del(struct file *file, char *buf, size_t size);
81 static ssize_t write_export(struct file *file, char *buf, size_t size);
82 static ssize_t write_unexport(struct file *file, char *buf, size_t size);
83 static ssize_t write_getfd(struct file *file, char *buf, size_t size);
84 static ssize_t write_getfs(struct file *file, char *buf, size_t size);
85 static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
86 static ssize_t write_threads(struct file *file, char *buf, size_t size);
87 static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
88 static ssize_t write_versions(struct file *file, char *buf, size_t size);
89 static ssize_t write_ports(struct file *file, char *buf, size_t size);
90 static ssize_t write_maxblksize(struct file *file, char *buf, size_t size);
91 #ifdef CONFIG_NFSD_V4
92 static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
93 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
94 #endif
95 
96 static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size);
97 static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size);
98 
99 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
100 	[NFSD_Svc] = write_svc,
101 	[NFSD_Add] = write_add,
102 	[NFSD_Del] = write_del,
103 	[NFSD_Export] = write_export,
104 	[NFSD_Unexport] = write_unexport,
105 	[NFSD_Getfd] = write_getfd,
106 	[NFSD_Getfs] = write_getfs,
107 	[NFSD_Fh] = write_filehandle,
108 	[NFSD_FO_UnlockIP] = failover_unlock_ip,
109 	[NFSD_FO_UnlockFS] = failover_unlock_fs,
110 	[NFSD_Threads] = write_threads,
111 	[NFSD_Pool_Threads] = write_pool_threads,
112 	[NFSD_Versions] = write_versions,
113 	[NFSD_Ports] = write_ports,
114 	[NFSD_MaxBlkSize] = write_maxblksize,
115 #ifdef CONFIG_NFSD_V4
116 	[NFSD_Leasetime] = write_leasetime,
117 	[NFSD_RecoveryDir] = write_recoverydir,
118 #endif
119 };
120 
121 static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
122 {
123 	ino_t ino =  file->f_path.dentry->d_inode->i_ino;
124 	char *data;
125 	ssize_t rv;
126 
127 	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
128 		return -EINVAL;
129 
130 	data = simple_transaction_get(file, buf, size);
131 	if (IS_ERR(data))
132 		return PTR_ERR(data);
133 
134 	rv =  write_op[ino](file, data, size);
135 	if (rv >= 0) {
136 		simple_transaction_set(file, rv);
137 		rv = size;
138 	}
139 	return rv;
140 }
141 
142 static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
143 {
144 	if (! file->private_data) {
145 		/* An attempt to read a transaction file without writing
146 		 * causes a 0-byte write so that the file can return
147 		 * state information
148 		 */
149 		ssize_t rv = nfsctl_transaction_write(file, buf, 0, pos);
150 		if (rv < 0)
151 			return rv;
152 	}
153 	return simple_transaction_read(file, buf, size, pos);
154 }
155 
156 static const struct file_operations transaction_ops = {
157 	.write		= nfsctl_transaction_write,
158 	.read		= nfsctl_transaction_read,
159 	.release	= simple_transaction_release,
160 };
161 
162 static int exports_open(struct inode *inode, struct file *file)
163 {
164 	return seq_open(file, &nfs_exports_op);
165 }
166 
167 static const struct file_operations exports_operations = {
168 	.open		= exports_open,
169 	.read		= seq_read,
170 	.llseek		= seq_lseek,
171 	.release	= seq_release,
172 	.owner		= THIS_MODULE,
173 };
174 
175 /*----------------------------------------------------------------------------*/
176 /*
177  * payload - write methods
178  * If the method has a response, the response should be put in buf,
179  * and the length returned.  Otherwise return 0 or and -error.
180  */
181 
182 static ssize_t write_svc(struct file *file, char *buf, size_t size)
183 {
184 	struct nfsctl_svc *data;
185 	if (size < sizeof(*data))
186 		return -EINVAL;
187 	data = (struct nfsctl_svc*) buf;
188 	return nfsd_svc(data->svc_port, data->svc_nthreads);
189 }
190 
191 static ssize_t write_add(struct file *file, char *buf, size_t size)
192 {
193 	struct nfsctl_client *data;
194 	if (size < sizeof(*data))
195 		return -EINVAL;
196 	data = (struct nfsctl_client *)buf;
197 	return exp_addclient(data);
198 }
199 
200 static ssize_t write_del(struct file *file, char *buf, size_t size)
201 {
202 	struct nfsctl_client *data;
203 	if (size < sizeof(*data))
204 		return -EINVAL;
205 	data = (struct nfsctl_client *)buf;
206 	return exp_delclient(data);
207 }
208 
209 static ssize_t write_export(struct file *file, char *buf, size_t size)
210 {
211 	struct nfsctl_export *data;
212 	if (size < sizeof(*data))
213 		return -EINVAL;
214 	data = (struct nfsctl_export*)buf;
215 	return exp_export(data);
216 }
217 
218 static ssize_t write_unexport(struct file *file, char *buf, size_t size)
219 {
220 	struct nfsctl_export *data;
221 
222 	if (size < sizeof(*data))
223 		return -EINVAL;
224 	data = (struct nfsctl_export*)buf;
225 	return exp_unexport(data);
226 }
227 
228 static ssize_t write_getfs(struct file *file, char *buf, size_t size)
229 {
230 	struct nfsctl_fsparm *data;
231 	struct sockaddr_in *sin;
232 	struct auth_domain *clp;
233 	int err = 0;
234 	struct knfsd_fh *res;
235 	struct in6_addr in6;
236 
237 	if (size < sizeof(*data))
238 		return -EINVAL;
239 	data = (struct nfsctl_fsparm*)buf;
240 	err = -EPROTONOSUPPORT;
241 	if (data->gd_addr.sa_family != AF_INET)
242 		goto out;
243 	sin = (struct sockaddr_in *)&data->gd_addr;
244 	if (data->gd_maxlen > NFS3_FHSIZE)
245 		data->gd_maxlen = NFS3_FHSIZE;
246 
247 	res = (struct knfsd_fh*)buf;
248 
249 	exp_readlock();
250 
251 	ipv6_addr_set_v4mapped(sin->sin_addr.s_addr, &in6);
252 
253 	clp = auth_unix_lookup(&in6);
254 	if (!clp)
255 		err = -EPERM;
256 	else {
257 		err = exp_rootfh(clp, data->gd_path, res, data->gd_maxlen);
258 		auth_domain_put(clp);
259 	}
260 	exp_readunlock();
261 	if (err == 0)
262 		err = res->fh_size + offsetof(struct knfsd_fh, fh_base);
263  out:
264 	return err;
265 }
266 
267 static ssize_t write_getfd(struct file *file, char *buf, size_t size)
268 {
269 	struct nfsctl_fdparm *data;
270 	struct sockaddr_in *sin;
271 	struct auth_domain *clp;
272 	int err = 0;
273 	struct knfsd_fh fh;
274 	char *res;
275 	struct in6_addr in6;
276 
277 	if (size < sizeof(*data))
278 		return -EINVAL;
279 	data = (struct nfsctl_fdparm*)buf;
280 	err = -EPROTONOSUPPORT;
281 	if (data->gd_addr.sa_family != AF_INET)
282 		goto out;
283 	err = -EINVAL;
284 	if (data->gd_version < 2 || data->gd_version > NFSSVC_MAXVERS)
285 		goto out;
286 
287 	res = buf;
288 	sin = (struct sockaddr_in *)&data->gd_addr;
289 	exp_readlock();
290 
291 	ipv6_addr_set_v4mapped(sin->sin_addr.s_addr, &in6);
292 
293 	clp = auth_unix_lookup(&in6);
294 	if (!clp)
295 		err = -EPERM;
296 	else {
297 		err = exp_rootfh(clp, data->gd_path, &fh, NFS_FHSIZE);
298 		auth_domain_put(clp);
299 	}
300 	exp_readunlock();
301 
302 	if (err == 0) {
303 		memset(res,0, NFS_FHSIZE);
304 		memcpy(res, &fh.fh_base, fh.fh_size);
305 		err = NFS_FHSIZE;
306 	}
307  out:
308 	return err;
309 }
310 
311 static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size)
312 {
313 	__be32 server_ip;
314 	char *fo_path, c;
315 	int b1, b2, b3, b4;
316 
317 	/* sanity check */
318 	if (size == 0)
319 		return -EINVAL;
320 
321 	if (buf[size-1] != '\n')
322 		return -EINVAL;
323 
324 	fo_path = buf;
325 	if (qword_get(&buf, fo_path, size) < 0)
326 		return -EINVAL;
327 
328 	/* get ipv4 address */
329 	if (sscanf(fo_path, "%u.%u.%u.%u%c", &b1, &b2, &b3, &b4, &c) != 4)
330 		return -EINVAL;
331 	server_ip = htonl((((((b1<<8)|b2)<<8)|b3)<<8)|b4);
332 
333 	return nlmsvc_unlock_all_by_ip(server_ip);
334 }
335 
336 static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size)
337 {
338 	struct nameidata nd;
339 	char *fo_path;
340 	int error;
341 
342 	/* sanity check */
343 	if (size == 0)
344 		return -EINVAL;
345 
346 	if (buf[size-1] != '\n')
347 		return -EINVAL;
348 
349 	fo_path = buf;
350 	if (qword_get(&buf, fo_path, size) < 0)
351 		return -EINVAL;
352 
353 	error = path_lookup(fo_path, 0, &nd);
354 	if (error)
355 		return error;
356 
357 	error = nlmsvc_unlock_all_by_sb(nd.path.mnt->mnt_sb);
358 
359 	path_put(&nd.path);
360 	return error;
361 }
362 
363 static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
364 {
365 	/* request is:
366 	 *   domain path maxsize
367 	 * response is
368 	 *   filehandle
369 	 *
370 	 * qword quoting is used, so filehandle will be \x....
371 	 */
372 	char *dname, *path;
373 	int uninitialized_var(maxsize);
374 	char *mesg = buf;
375 	int len;
376 	struct auth_domain *dom;
377 	struct knfsd_fh fh;
378 
379 	if (size == 0)
380 		return -EINVAL;
381 
382 	if (buf[size-1] != '\n')
383 		return -EINVAL;
384 	buf[size-1] = 0;
385 
386 	dname = mesg;
387 	len = qword_get(&mesg, dname, size);
388 	if (len <= 0) return -EINVAL;
389 
390 	path = dname+len+1;
391 	len = qword_get(&mesg, path, size);
392 	if (len <= 0) return -EINVAL;
393 
394 	len = get_int(&mesg, &maxsize);
395 	if (len)
396 		return len;
397 
398 	if (maxsize < NFS_FHSIZE)
399 		return -EINVAL;
400 	if (maxsize > NFS3_FHSIZE)
401 		maxsize = NFS3_FHSIZE;
402 
403 	if (qword_get(&mesg, mesg, size)>0)
404 		return -EINVAL;
405 
406 	/* we have all the words, they are in buf.. */
407 	dom = unix_domain_find(dname);
408 	if (!dom)
409 		return -ENOMEM;
410 
411 	len = exp_rootfh(dom, path, &fh,  maxsize);
412 	auth_domain_put(dom);
413 	if (len)
414 		return len;
415 
416 	mesg = buf; len = SIMPLE_TRANSACTION_LIMIT;
417 	qword_addhex(&mesg, &len, (char*)&fh.fh_base, fh.fh_size);
418 	mesg[-1] = '\n';
419 	return mesg - buf;
420 }
421 
422 static ssize_t write_threads(struct file *file, char *buf, size_t size)
423 {
424 	/* if size > 0, look for a number of threads and call nfsd_svc
425 	 * then write out number of threads as reply
426 	 */
427 	char *mesg = buf;
428 	int rv;
429 	if (size > 0) {
430 		int newthreads;
431 		rv = get_int(&mesg, &newthreads);
432 		if (rv)
433 			return rv;
434 		if (newthreads <0)
435 			return -EINVAL;
436 		rv = nfsd_svc(2049, newthreads);
437 		if (rv)
438 			return rv;
439 	}
440 	sprintf(buf, "%d\n", nfsd_nrthreads());
441 	return strlen(buf);
442 }
443 
444 static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
445 {
446 	/* if size > 0, look for an array of number of threads per node
447 	 * and apply them  then write out number of threads per node as reply
448 	 */
449 	char *mesg = buf;
450 	int i;
451 	int rv;
452 	int len;
453     	int npools = nfsd_nrpools();
454 	int *nthreads;
455 
456 	if (npools == 0) {
457 		/*
458 		 * NFS is shut down.  The admin can start it by
459 		 * writing to the threads file but NOT the pool_threads
460 		 * file, sorry.  Report zero threads.
461 		 */
462 		strcpy(buf, "0\n");
463 		return strlen(buf);
464 	}
465 
466 	nthreads = kcalloc(npools, sizeof(int), GFP_KERNEL);
467 	if (nthreads == NULL)
468 		return -ENOMEM;
469 
470 	if (size > 0) {
471 		for (i = 0; i < npools; i++) {
472 			rv = get_int(&mesg, &nthreads[i]);
473 			if (rv == -ENOENT)
474 				break;		/* fewer numbers than pools */
475 			if (rv)
476 				goto out_free;	/* syntax error */
477 			rv = -EINVAL;
478 			if (nthreads[i] < 0)
479 				goto out_free;
480 		}
481 		rv = nfsd_set_nrthreads(i, nthreads);
482 		if (rv)
483 			goto out_free;
484 	}
485 
486 	rv = nfsd_get_nrthreads(npools, nthreads);
487 	if (rv)
488 		goto out_free;
489 
490 	mesg = buf;
491 	size = SIMPLE_TRANSACTION_LIMIT;
492 	for (i = 0; i < npools && size > 0; i++) {
493 		snprintf(mesg, size, "%d%c", nthreads[i], (i == npools-1 ? '\n' : ' '));
494 		len = strlen(mesg);
495 		size -= len;
496 		mesg += len;
497 	}
498 
499 	return (mesg-buf);
500 
501 out_free:
502 	kfree(nthreads);
503 	return rv;
504 }
505 
506 static ssize_t write_versions(struct file *file, char *buf, size_t size)
507 {
508 	/*
509 	 * Format:
510 	 *   [-/+]vers [-/+]vers ...
511 	 */
512 	char *mesg = buf;
513 	char *vers, sign;
514 	int len, num;
515 	ssize_t tlen = 0;
516 	char *sep;
517 
518 	if (size>0) {
519 		if (nfsd_serv)
520 			/* Cannot change versions without updating
521 			 * nfsd_serv->sv_xdrsize, and reallocing
522 			 * rq_argp and rq_resp
523 			 */
524 			return -EBUSY;
525 		if (buf[size-1] != '\n')
526 			return -EINVAL;
527 		buf[size-1] = 0;
528 
529 		vers = mesg;
530 		len = qword_get(&mesg, vers, size);
531 		if (len <= 0) return -EINVAL;
532 		do {
533 			sign = *vers;
534 			if (sign == '+' || sign == '-')
535 				num = simple_strtol((vers+1), NULL, 0);
536 			else
537 				num = simple_strtol(vers, NULL, 0);
538 			switch(num) {
539 			case 2:
540 			case 3:
541 			case 4:
542 				nfsd_vers(num, sign == '-' ? NFSD_CLEAR : NFSD_SET);
543 				break;
544 			default:
545 				return -EINVAL;
546 			}
547 			vers += len + 1;
548 			tlen += len;
549 		} while ((len = qword_get(&mesg, vers, size)) > 0);
550 		/* If all get turned off, turn them back on, as
551 		 * having no versions is BAD
552 		 */
553 		nfsd_reset_versions();
554 	}
555 	/* Now write current state into reply buffer */
556 	len = 0;
557 	sep = "";
558 	for (num=2 ; num <= 4 ; num++)
559 		if (nfsd_vers(num, NFSD_AVAIL)) {
560 			len += sprintf(buf+len, "%s%c%d", sep,
561 				       nfsd_vers(num, NFSD_TEST)?'+':'-',
562 				       num);
563 			sep = " ";
564 		}
565 	len += sprintf(buf+len, "\n");
566 	return len;
567 }
568 
569 static ssize_t write_ports(struct file *file, char *buf, size_t size)
570 {
571 	if (size == 0) {
572 		int len = 0;
573 		lock_kernel();
574 		if (nfsd_serv)
575 			len = svc_xprt_names(nfsd_serv, buf, 0);
576 		unlock_kernel();
577 		return len;
578 	}
579 	/* Either a single 'fd' number is written, in which
580 	 * case it must be for a socket of a supported family/protocol,
581 	 * and we use it as an nfsd socket, or
582 	 * A '-' followed by the 'name' of a socket in which case
583 	 * we close the socket.
584 	 */
585 	if (isdigit(buf[0])) {
586 		char *mesg = buf;
587 		int fd;
588 		int err;
589 		err = get_int(&mesg, &fd);
590 		if (err)
591 			return -EINVAL;
592 		if (fd < 0)
593 			return -EINVAL;
594 		err = nfsd_create_serv();
595 		if (!err) {
596 			int proto = 0;
597 			err = svc_addsock(nfsd_serv, fd, buf, &proto);
598 			if (err >= 0) {
599 				err = lockd_up(proto);
600 				if (err < 0)
601 					svc_sock_names(buf+strlen(buf)+1, nfsd_serv, buf);
602 			}
603 			/* Decrease the count, but don't shutdown the
604 			 * the service
605 			 */
606 			lock_kernel();
607 			nfsd_serv->sv_nrthreads--;
608 			unlock_kernel();
609 		}
610 		return err < 0 ? err : 0;
611 	}
612 	if (buf[0] == '-' && isdigit(buf[1])) {
613 		char *toclose = kstrdup(buf+1, GFP_KERNEL);
614 		int len = 0;
615 		if (!toclose)
616 			return -ENOMEM;
617 		lock_kernel();
618 		if (nfsd_serv)
619 			len = svc_sock_names(buf, nfsd_serv, toclose);
620 		unlock_kernel();
621 		if (len >= 0)
622 			lockd_down();
623 		kfree(toclose);
624 		return len;
625 	}
626 	/*
627 	 * Add a transport listener by writing it's transport name
628 	 */
629 	if (isalpha(buf[0])) {
630 		int err;
631 		char transport[16];
632 		int port;
633 		if (sscanf(buf, "%15s %4d", transport, &port) == 2) {
634 			err = nfsd_create_serv();
635 			if (!err) {
636 				err = svc_create_xprt(nfsd_serv,
637 						      transport, port,
638 						      SVC_SOCK_ANONYMOUS);
639 				if (err == -ENOENT)
640 					/* Give a reasonable perror msg for
641 					 * bad transport string */
642 					err = -EPROTONOSUPPORT;
643 			}
644 			return err < 0 ? err : 0;
645 		}
646 	}
647 	/*
648 	 * Remove a transport by writing it's transport name and port number
649 	 */
650 	if (buf[0] == '-' && isalpha(buf[1])) {
651 		struct svc_xprt *xprt;
652 		int err = -EINVAL;
653 		char transport[16];
654 		int port;
655 		if (sscanf(&buf[1], "%15s %4d", transport, &port) == 2) {
656 			if (port == 0)
657 				return -EINVAL;
658 			lock_kernel();
659 			if (nfsd_serv) {
660 				xprt = svc_find_xprt(nfsd_serv, transport,
661 						     AF_UNSPEC, port);
662 				if (xprt) {
663 					svc_close_xprt(xprt);
664 					svc_xprt_put(xprt);
665 					err = 0;
666 				} else
667 					err = -ENOTCONN;
668 			}
669 			unlock_kernel();
670 			return err < 0 ? err : 0;
671 		}
672 	}
673 	return -EINVAL;
674 }
675 
676 int nfsd_max_blksize;
677 
678 static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
679 {
680 	char *mesg = buf;
681 	if (size > 0) {
682 		int bsize;
683 		int rv = get_int(&mesg, &bsize);
684 		if (rv)
685 			return rv;
686 		/* force bsize into allowed range and
687 		 * required alignment.
688 		 */
689 		if (bsize < 1024)
690 			bsize = 1024;
691 		if (bsize > NFSSVC_MAXBLKSIZE)
692 			bsize = NFSSVC_MAXBLKSIZE;
693 		bsize &= ~(1024-1);
694 		lock_kernel();
695 		if (nfsd_serv && nfsd_serv->sv_nrthreads) {
696 			unlock_kernel();
697 			return -EBUSY;
698 		}
699 		nfsd_max_blksize = bsize;
700 		unlock_kernel();
701 	}
702 	return sprintf(buf, "%d\n", nfsd_max_blksize);
703 }
704 
705 #ifdef CONFIG_NFSD_V4
706 extern time_t nfs4_leasetime(void);
707 
708 static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
709 {
710 	/* if size > 10 seconds, call
711 	 * nfs4_reset_lease() then write out the new lease (seconds) as reply
712 	 */
713 	char *mesg = buf;
714 	int rv;
715 
716 	if (size > 0) {
717 		int lease;
718 		rv = get_int(&mesg, &lease);
719 		if (rv)
720 			return rv;
721 		if (lease < 10 || lease > 3600)
722 			return -EINVAL;
723 		nfs4_reset_lease(lease);
724 	}
725 	sprintf(buf, "%ld\n", nfs4_lease_time());
726 	return strlen(buf);
727 }
728 
729 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
730 {
731 	char *mesg = buf;
732 	char *recdir;
733 	int len, status;
734 
735 	if (size == 0 || size > PATH_MAX || buf[size-1] != '\n')
736 		return -EINVAL;
737 	buf[size-1] = 0;
738 
739 	recdir = mesg;
740 	len = qword_get(&mesg, recdir, size);
741 	if (len <= 0)
742 		return -EINVAL;
743 
744 	status = nfs4_reset_recoverydir(recdir);
745 	return strlen(buf);
746 }
747 #endif
748 
749 /*----------------------------------------------------------------------------*/
750 /*
751  *	populating the filesystem.
752  */
753 
754 static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
755 {
756 	static struct tree_descr nfsd_files[] = {
757 		[NFSD_Svc] = {".svc", &transaction_ops, S_IWUSR},
758 		[NFSD_Add] = {".add", &transaction_ops, S_IWUSR},
759 		[NFSD_Del] = {".del", &transaction_ops, S_IWUSR},
760 		[NFSD_Export] = {".export", &transaction_ops, S_IWUSR},
761 		[NFSD_Unexport] = {".unexport", &transaction_ops, S_IWUSR},
762 		[NFSD_Getfd] = {".getfd", &transaction_ops, S_IWUSR|S_IRUSR},
763 		[NFSD_Getfs] = {".getfs", &transaction_ops, S_IWUSR|S_IRUSR},
764 		[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
765 		[NFSD_FO_UnlockIP] = {"unlock_ip",
766 					&transaction_ops, S_IWUSR|S_IRUSR},
767 		[NFSD_FO_UnlockFS] = {"unlock_filesystem",
768 					&transaction_ops, S_IWUSR|S_IRUSR},
769 		[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
770 		[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
771 		[NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
772 		[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
773 		[NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
774 		[NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
775 #ifdef CONFIG_NFSD_V4
776 		[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
777 		[NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
778 #endif
779 		/* last one */ {""}
780 	};
781 	return simple_fill_super(sb, 0x6e667364, nfsd_files);
782 }
783 
784 static int nfsd_get_sb(struct file_system_type *fs_type,
785 	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
786 {
787 	return get_sb_single(fs_type, flags, data, nfsd_fill_super, mnt);
788 }
789 
790 static struct file_system_type nfsd_fs_type = {
791 	.owner		= THIS_MODULE,
792 	.name		= "nfsd",
793 	.get_sb		= nfsd_get_sb,
794 	.kill_sb	= kill_litter_super,
795 };
796 
797 #ifdef CONFIG_PROC_FS
798 static int create_proc_exports_entry(void)
799 {
800 	struct proc_dir_entry *entry;
801 
802 	entry = proc_mkdir("fs/nfs", NULL);
803 	if (!entry)
804 		return -ENOMEM;
805 	entry = proc_create("exports", 0, entry, &exports_operations);
806 	if (!entry)
807 		return -ENOMEM;
808 	return 0;
809 }
810 #else /* CONFIG_PROC_FS */
811 static int create_proc_exports_entry(void)
812 {
813 	return 0;
814 }
815 #endif
816 
817 static int __init init_nfsd(void)
818 {
819 	int retval;
820 	printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@monad.swb.de).\n");
821 
822 	retval = nfs4_state_init(); /* nfs4 locking state */
823 	if (retval)
824 		return retval;
825 	nfsd_stat_init();	/* Statistics */
826 	retval = nfsd_reply_cache_init();
827 	if (retval)
828 		goto out_free_stat;
829 	retval = nfsd_export_init();
830 	if (retval)
831 		goto out_free_cache;
832 	nfsd_lockd_init();	/* lockd->nfsd callbacks */
833 	retval = nfsd_idmap_init();
834 	if (retval)
835 		goto out_free_lockd;
836 	retval = create_proc_exports_entry();
837 	if (retval)
838 		goto out_free_idmap;
839 	retval = register_filesystem(&nfsd_fs_type);
840 	if (retval)
841 		goto out_free_all;
842 	return 0;
843 out_free_all:
844 	remove_proc_entry("fs/nfs/exports", NULL);
845 	remove_proc_entry("fs/nfs", NULL);
846 out_free_idmap:
847 	nfsd_idmap_shutdown();
848 out_free_lockd:
849 	nfsd_lockd_shutdown();
850 	nfsd_export_shutdown();
851 out_free_cache:
852 	nfsd_reply_cache_shutdown();
853 out_free_stat:
854 	nfsd_stat_shutdown();
855 	nfsd4_free_slabs();
856 	return retval;
857 }
858 
859 static void __exit exit_nfsd(void)
860 {
861 	nfsd_export_shutdown();
862 	nfsd_reply_cache_shutdown();
863 	remove_proc_entry("fs/nfs/exports", NULL);
864 	remove_proc_entry("fs/nfs", NULL);
865 	nfsd_stat_shutdown();
866 	nfsd_lockd_shutdown();
867 	nfsd_idmap_shutdown();
868 	nfsd4_free_slabs();
869 	unregister_filesystem(&nfsd_fs_type);
870 }
871 
872 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
873 MODULE_LICENSE("GPL");
874 module_init(init_nfsd)
875 module_exit(exit_nfsd)
876