xref: /openbmc/linux/fs/nfsd/nfsctl.c (revision 545e4006)
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 	struct sockaddr_in sin = {
314 		.sin_family	= AF_INET,
315 	};
316 	int b1, b2, b3, b4;
317 	char c;
318 	char *fo_path;
319 
320 	/* sanity check */
321 	if (size == 0)
322 		return -EINVAL;
323 
324 	if (buf[size-1] != '\n')
325 		return -EINVAL;
326 
327 	fo_path = buf;
328 	if (qword_get(&buf, fo_path, size) < 0)
329 		return -EINVAL;
330 
331 	/* get ipv4 address */
332 	if (sscanf(fo_path, NIPQUAD_FMT "%c", &b1, &b2, &b3, &b4, &c) != 4)
333 		return -EINVAL;
334 	if (b1 > 255 || b2 > 255 || b3 > 255 || b4 > 255)
335 		return -EINVAL;
336 	sin.sin_addr.s_addr = htonl((b1 << 24) | (b2 << 16) | (b3 << 8) | b4);
337 
338 	return nlmsvc_unlock_all_by_ip((struct sockaddr *)&sin);
339 }
340 
341 static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size)
342 {
343 	struct nameidata nd;
344 	char *fo_path;
345 	int error;
346 
347 	/* sanity check */
348 	if (size == 0)
349 		return -EINVAL;
350 
351 	if (buf[size-1] != '\n')
352 		return -EINVAL;
353 
354 	fo_path = buf;
355 	if (qword_get(&buf, fo_path, size) < 0)
356 		return -EINVAL;
357 
358 	error = path_lookup(fo_path, 0, &nd);
359 	if (error)
360 		return error;
361 
362 	error = nlmsvc_unlock_all_by_sb(nd.path.mnt->mnt_sb);
363 
364 	path_put(&nd.path);
365 	return error;
366 }
367 
368 static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
369 {
370 	/* request is:
371 	 *   domain path maxsize
372 	 * response is
373 	 *   filehandle
374 	 *
375 	 * qword quoting is used, so filehandle will be \x....
376 	 */
377 	char *dname, *path;
378 	int uninitialized_var(maxsize);
379 	char *mesg = buf;
380 	int len;
381 	struct auth_domain *dom;
382 	struct knfsd_fh fh;
383 
384 	if (size == 0)
385 		return -EINVAL;
386 
387 	if (buf[size-1] != '\n')
388 		return -EINVAL;
389 	buf[size-1] = 0;
390 
391 	dname = mesg;
392 	len = qword_get(&mesg, dname, size);
393 	if (len <= 0) return -EINVAL;
394 
395 	path = dname+len+1;
396 	len = qword_get(&mesg, path, size);
397 	if (len <= 0) return -EINVAL;
398 
399 	len = get_int(&mesg, &maxsize);
400 	if (len)
401 		return len;
402 
403 	if (maxsize < NFS_FHSIZE)
404 		return -EINVAL;
405 	if (maxsize > NFS3_FHSIZE)
406 		maxsize = NFS3_FHSIZE;
407 
408 	if (qword_get(&mesg, mesg, size)>0)
409 		return -EINVAL;
410 
411 	/* we have all the words, they are in buf.. */
412 	dom = unix_domain_find(dname);
413 	if (!dom)
414 		return -ENOMEM;
415 
416 	len = exp_rootfh(dom, path, &fh,  maxsize);
417 	auth_domain_put(dom);
418 	if (len)
419 		return len;
420 
421 	mesg = buf; len = SIMPLE_TRANSACTION_LIMIT;
422 	qword_addhex(&mesg, &len, (char*)&fh.fh_base, fh.fh_size);
423 	mesg[-1] = '\n';
424 	return mesg - buf;
425 }
426 
427 static ssize_t write_threads(struct file *file, char *buf, size_t size)
428 {
429 	/* if size > 0, look for a number of threads and call nfsd_svc
430 	 * then write out number of threads as reply
431 	 */
432 	char *mesg = buf;
433 	int rv;
434 	if (size > 0) {
435 		int newthreads;
436 		rv = get_int(&mesg, &newthreads);
437 		if (rv)
438 			return rv;
439 		if (newthreads <0)
440 			return -EINVAL;
441 		rv = nfsd_svc(2049, newthreads);
442 		if (rv)
443 			return rv;
444 	}
445 	sprintf(buf, "%d\n", nfsd_nrthreads());
446 	return strlen(buf);
447 }
448 
449 static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
450 {
451 	/* if size > 0, look for an array of number of threads per node
452 	 * and apply them  then write out number of threads per node as reply
453 	 */
454 	char *mesg = buf;
455 	int i;
456 	int rv;
457 	int len;
458 	int npools;
459 	int *nthreads;
460 
461 	mutex_lock(&nfsd_mutex);
462 	npools = nfsd_nrpools();
463 	if (npools == 0) {
464 		/*
465 		 * NFS is shut down.  The admin can start it by
466 		 * writing to the threads file but NOT the pool_threads
467 		 * file, sorry.  Report zero threads.
468 		 */
469 		mutex_unlock(&nfsd_mutex);
470 		strcpy(buf, "0\n");
471 		return strlen(buf);
472 	}
473 
474 	nthreads = kcalloc(npools, sizeof(int), GFP_KERNEL);
475 	rv = -ENOMEM;
476 	if (nthreads == NULL)
477 		goto out_free;
478 
479 	if (size > 0) {
480 		for (i = 0; i < npools; i++) {
481 			rv = get_int(&mesg, &nthreads[i]);
482 			if (rv == -ENOENT)
483 				break;		/* fewer numbers than pools */
484 			if (rv)
485 				goto out_free;	/* syntax error */
486 			rv = -EINVAL;
487 			if (nthreads[i] < 0)
488 				goto out_free;
489 		}
490 		rv = nfsd_set_nrthreads(i, nthreads);
491 		if (rv)
492 			goto out_free;
493 	}
494 
495 	rv = nfsd_get_nrthreads(npools, nthreads);
496 	if (rv)
497 		goto out_free;
498 
499 	mesg = buf;
500 	size = SIMPLE_TRANSACTION_LIMIT;
501 	for (i = 0; i < npools && size > 0; i++) {
502 		snprintf(mesg, size, "%d%c", nthreads[i], (i == npools-1 ? '\n' : ' '));
503 		len = strlen(mesg);
504 		size -= len;
505 		mesg += len;
506 	}
507 
508 	mutex_unlock(&nfsd_mutex);
509 	return (mesg-buf);
510 
511 out_free:
512 	kfree(nthreads);
513 	mutex_unlock(&nfsd_mutex);
514 	return rv;
515 }
516 
517 static ssize_t __write_versions(struct file *file, char *buf, size_t size)
518 {
519 	/*
520 	 * Format:
521 	 *   [-/+]vers [-/+]vers ...
522 	 */
523 	char *mesg = buf;
524 	char *vers, sign;
525 	int len, num;
526 	ssize_t tlen = 0;
527 	char *sep;
528 
529 	if (size>0) {
530 		if (nfsd_serv)
531 			/* Cannot change versions without updating
532 			 * nfsd_serv->sv_xdrsize, and reallocing
533 			 * rq_argp and rq_resp
534 			 */
535 			return -EBUSY;
536 		if (buf[size-1] != '\n')
537 			return -EINVAL;
538 		buf[size-1] = 0;
539 
540 		vers = mesg;
541 		len = qword_get(&mesg, vers, size);
542 		if (len <= 0) return -EINVAL;
543 		do {
544 			sign = *vers;
545 			if (sign == '+' || sign == '-')
546 				num = simple_strtol((vers+1), NULL, 0);
547 			else
548 				num = simple_strtol(vers, NULL, 0);
549 			switch(num) {
550 			case 2:
551 			case 3:
552 			case 4:
553 				nfsd_vers(num, sign == '-' ? NFSD_CLEAR : NFSD_SET);
554 				break;
555 			default:
556 				return -EINVAL;
557 			}
558 			vers += len + 1;
559 			tlen += len;
560 		} while ((len = qword_get(&mesg, vers, size)) > 0);
561 		/* If all get turned off, turn them back on, as
562 		 * having no versions is BAD
563 		 */
564 		nfsd_reset_versions();
565 	}
566 	/* Now write current state into reply buffer */
567 	len = 0;
568 	sep = "";
569 	for (num=2 ; num <= 4 ; num++)
570 		if (nfsd_vers(num, NFSD_AVAIL)) {
571 			len += sprintf(buf+len, "%s%c%d", sep,
572 				       nfsd_vers(num, NFSD_TEST)?'+':'-',
573 				       num);
574 			sep = " ";
575 		}
576 	len += sprintf(buf+len, "\n");
577 	return len;
578 }
579 
580 static ssize_t write_versions(struct file *file, char *buf, size_t size)
581 {
582 	ssize_t rv;
583 
584 	mutex_lock(&nfsd_mutex);
585 	rv = __write_versions(file, buf, size);
586 	mutex_unlock(&nfsd_mutex);
587 	return rv;
588 }
589 
590 static ssize_t __write_ports(struct file *file, char *buf, size_t size)
591 {
592 	if (size == 0) {
593 		int len = 0;
594 
595 		if (nfsd_serv)
596 			len = svc_xprt_names(nfsd_serv, buf, 0);
597 		return len;
598 	}
599 	/* Either a single 'fd' number is written, in which
600 	 * case it must be for a socket of a supported family/protocol,
601 	 * and we use it as an nfsd socket, or
602 	 * A '-' followed by the 'name' of a socket in which case
603 	 * we close the socket.
604 	 */
605 	if (isdigit(buf[0])) {
606 		char *mesg = buf;
607 		int fd;
608 		int err;
609 		err = get_int(&mesg, &fd);
610 		if (err)
611 			return -EINVAL;
612 		if (fd < 0)
613 			return -EINVAL;
614 		err = nfsd_create_serv();
615 		if (!err) {
616 			int proto = 0;
617 			err = svc_addsock(nfsd_serv, fd, buf, &proto);
618 			if (err >= 0) {
619 				err = lockd_up(proto);
620 				if (err < 0)
621 					svc_sock_names(buf+strlen(buf)+1, nfsd_serv, buf);
622 			}
623 			/* Decrease the count, but don't shutdown the
624 			 * the service
625 			 */
626 			nfsd_serv->sv_nrthreads--;
627 		}
628 		return err < 0 ? err : 0;
629 	}
630 	if (buf[0] == '-' && isdigit(buf[1])) {
631 		char *toclose = kstrdup(buf+1, GFP_KERNEL);
632 		int len = 0;
633 		if (!toclose)
634 			return -ENOMEM;
635 		if (nfsd_serv)
636 			len = svc_sock_names(buf, nfsd_serv, toclose);
637 		if (len >= 0)
638 			lockd_down();
639 		kfree(toclose);
640 		return len;
641 	}
642 	/*
643 	 * Add a transport listener by writing it's transport name
644 	 */
645 	if (isalpha(buf[0])) {
646 		int err;
647 		char transport[16];
648 		int port;
649 		if (sscanf(buf, "%15s %4d", transport, &port) == 2) {
650 			err = nfsd_create_serv();
651 			if (!err) {
652 				err = svc_create_xprt(nfsd_serv,
653 						      transport, port,
654 						      SVC_SOCK_ANONYMOUS);
655 				if (err == -ENOENT)
656 					/* Give a reasonable perror msg for
657 					 * bad transport string */
658 					err = -EPROTONOSUPPORT;
659 			}
660 			return err < 0 ? err : 0;
661 		}
662 	}
663 	/*
664 	 * Remove a transport by writing it's transport name and port number
665 	 */
666 	if (buf[0] == '-' && isalpha(buf[1])) {
667 		struct svc_xprt *xprt;
668 		int err = -EINVAL;
669 		char transport[16];
670 		int port;
671 		if (sscanf(&buf[1], "%15s %4d", transport, &port) == 2) {
672 			if (port == 0)
673 				return -EINVAL;
674 			if (nfsd_serv) {
675 				xprt = svc_find_xprt(nfsd_serv, transport,
676 						     AF_UNSPEC, port);
677 				if (xprt) {
678 					svc_close_xprt(xprt);
679 					svc_xprt_put(xprt);
680 					err = 0;
681 				} else
682 					err = -ENOTCONN;
683 			}
684 			return err < 0 ? err : 0;
685 		}
686 	}
687 	return -EINVAL;
688 }
689 
690 static ssize_t write_ports(struct file *file, char *buf, size_t size)
691 {
692 	ssize_t rv;
693 
694 	mutex_lock(&nfsd_mutex);
695 	rv = __write_ports(file, buf, size);
696 	mutex_unlock(&nfsd_mutex);
697 	return rv;
698 }
699 
700 
701 int nfsd_max_blksize;
702 
703 static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
704 {
705 	char *mesg = buf;
706 	if (size > 0) {
707 		int bsize;
708 		int rv = get_int(&mesg, &bsize);
709 		if (rv)
710 			return rv;
711 		/* force bsize into allowed range and
712 		 * required alignment.
713 		 */
714 		if (bsize < 1024)
715 			bsize = 1024;
716 		if (bsize > NFSSVC_MAXBLKSIZE)
717 			bsize = NFSSVC_MAXBLKSIZE;
718 		bsize &= ~(1024-1);
719 		mutex_lock(&nfsd_mutex);
720 		if (nfsd_serv && nfsd_serv->sv_nrthreads) {
721 			mutex_unlock(&nfsd_mutex);
722 			return -EBUSY;
723 		}
724 		nfsd_max_blksize = bsize;
725 		mutex_unlock(&nfsd_mutex);
726 	}
727 	return sprintf(buf, "%d\n", nfsd_max_blksize);
728 }
729 
730 #ifdef CONFIG_NFSD_V4
731 extern time_t nfs4_leasetime(void);
732 
733 static ssize_t __write_leasetime(struct file *file, char *buf, size_t size)
734 {
735 	/* if size > 10 seconds, call
736 	 * nfs4_reset_lease() then write out the new lease (seconds) as reply
737 	 */
738 	char *mesg = buf;
739 	int rv, lease;
740 
741 	if (size > 0) {
742 		if (nfsd_serv)
743 			return -EBUSY;
744 		rv = get_int(&mesg, &lease);
745 		if (rv)
746 			return rv;
747 		if (lease < 10 || lease > 3600)
748 			return -EINVAL;
749 		nfs4_reset_lease(lease);
750 	}
751 	sprintf(buf, "%ld\n", nfs4_lease_time());
752 	return strlen(buf);
753 }
754 
755 static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
756 {
757 	ssize_t rv;
758 
759 	mutex_lock(&nfsd_mutex);
760 	rv = __write_leasetime(file, buf, size);
761 	mutex_unlock(&nfsd_mutex);
762 	return rv;
763 }
764 
765 extern char *nfs4_recoverydir(void);
766 
767 static ssize_t __write_recoverydir(struct file *file, char *buf, size_t size)
768 {
769 	char *mesg = buf;
770 	char *recdir;
771 	int len, status;
772 
773 	if (size > 0) {
774 		if (nfsd_serv)
775 			return -EBUSY;
776 		if (size > PATH_MAX || buf[size-1] != '\n')
777 			return -EINVAL;
778 		buf[size-1] = 0;
779 
780 		recdir = mesg;
781 		len = qword_get(&mesg, recdir, size);
782 		if (len <= 0)
783 			return -EINVAL;
784 
785 		status = nfs4_reset_recoverydir(recdir);
786 	}
787 	sprintf(buf, "%s\n", nfs4_recoverydir());
788 	return strlen(buf);
789 }
790 
791 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
792 {
793 	ssize_t rv;
794 
795 	mutex_lock(&nfsd_mutex);
796 	rv = __write_recoverydir(file, buf, size);
797 	mutex_unlock(&nfsd_mutex);
798 	return rv;
799 }
800 
801 #endif
802 
803 /*----------------------------------------------------------------------------*/
804 /*
805  *	populating the filesystem.
806  */
807 
808 static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
809 {
810 	static struct tree_descr nfsd_files[] = {
811 		[NFSD_Svc] = {".svc", &transaction_ops, S_IWUSR},
812 		[NFSD_Add] = {".add", &transaction_ops, S_IWUSR},
813 		[NFSD_Del] = {".del", &transaction_ops, S_IWUSR},
814 		[NFSD_Export] = {".export", &transaction_ops, S_IWUSR},
815 		[NFSD_Unexport] = {".unexport", &transaction_ops, S_IWUSR},
816 		[NFSD_Getfd] = {".getfd", &transaction_ops, S_IWUSR|S_IRUSR},
817 		[NFSD_Getfs] = {".getfs", &transaction_ops, S_IWUSR|S_IRUSR},
818 		[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
819 		[NFSD_FO_UnlockIP] = {"unlock_ip",
820 					&transaction_ops, S_IWUSR|S_IRUSR},
821 		[NFSD_FO_UnlockFS] = {"unlock_filesystem",
822 					&transaction_ops, S_IWUSR|S_IRUSR},
823 		[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
824 		[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
825 		[NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
826 		[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
827 		[NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
828 		[NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
829 #ifdef CONFIG_NFSD_V4
830 		[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
831 		[NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
832 #endif
833 		/* last one */ {""}
834 	};
835 	return simple_fill_super(sb, 0x6e667364, nfsd_files);
836 }
837 
838 static int nfsd_get_sb(struct file_system_type *fs_type,
839 	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
840 {
841 	return get_sb_single(fs_type, flags, data, nfsd_fill_super, mnt);
842 }
843 
844 static struct file_system_type nfsd_fs_type = {
845 	.owner		= THIS_MODULE,
846 	.name		= "nfsd",
847 	.get_sb		= nfsd_get_sb,
848 	.kill_sb	= kill_litter_super,
849 };
850 
851 #ifdef CONFIG_PROC_FS
852 static int create_proc_exports_entry(void)
853 {
854 	struct proc_dir_entry *entry;
855 
856 	entry = proc_mkdir("fs/nfs", NULL);
857 	if (!entry)
858 		return -ENOMEM;
859 	entry = proc_create("exports", 0, entry, &exports_operations);
860 	if (!entry)
861 		return -ENOMEM;
862 	return 0;
863 }
864 #else /* CONFIG_PROC_FS */
865 static int create_proc_exports_entry(void)
866 {
867 	return 0;
868 }
869 #endif
870 
871 static int __init init_nfsd(void)
872 {
873 	int retval;
874 	printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@monad.swb.de).\n");
875 
876 	retval = nfs4_state_init(); /* nfs4 locking state */
877 	if (retval)
878 		return retval;
879 	nfsd_stat_init();	/* Statistics */
880 	retval = nfsd_reply_cache_init();
881 	if (retval)
882 		goto out_free_stat;
883 	retval = nfsd_export_init();
884 	if (retval)
885 		goto out_free_cache;
886 	nfsd_lockd_init();	/* lockd->nfsd callbacks */
887 	retval = nfsd_idmap_init();
888 	if (retval)
889 		goto out_free_lockd;
890 	retval = create_proc_exports_entry();
891 	if (retval)
892 		goto out_free_idmap;
893 	retval = register_filesystem(&nfsd_fs_type);
894 	if (retval)
895 		goto out_free_all;
896 	return 0;
897 out_free_all:
898 	remove_proc_entry("fs/nfs/exports", NULL);
899 	remove_proc_entry("fs/nfs", NULL);
900 out_free_idmap:
901 	nfsd_idmap_shutdown();
902 out_free_lockd:
903 	nfsd_lockd_shutdown();
904 	nfsd_export_shutdown();
905 out_free_cache:
906 	nfsd_reply_cache_shutdown();
907 out_free_stat:
908 	nfsd_stat_shutdown();
909 	nfsd4_free_slabs();
910 	return retval;
911 }
912 
913 static void __exit exit_nfsd(void)
914 {
915 	nfsd_export_shutdown();
916 	nfsd_reply_cache_shutdown();
917 	remove_proc_entry("fs/nfs/exports", NULL);
918 	remove_proc_entry("fs/nfs", NULL);
919 	nfsd_stat_shutdown();
920 	nfsd_lockd_shutdown();
921 	nfsd_idmap_shutdown();
922 	nfsd4_free_slabs();
923 	unregister_filesystem(&nfsd_fs_type);
924 }
925 
926 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
927 MODULE_LICENSE("GPL");
928 module_init(init_nfsd)
929 module_exit(exit_nfsd)
930