xref: /linux/fs/nfsd/nfsctl.c (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
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/namei.h>
16 #include <linux/fcntl.h>
17 #include <linux/net.h>
18 #include <linux/in.h>
19 #include <linux/syscalls.h>
20 #include <linux/unistd.h>
21 #include <linux/slab.h>
22 #include <linux/proc_fs.h>
23 #include <linux/seq_file.h>
24 #include <linux/pagemap.h>
25 #include <linux/init.h>
26 #include <linux/inet.h>
27 #include <linux/string.h>
28 #include <linux/smp_lock.h>
29 #include <linux/ctype.h>
30 
31 #include <linux/nfs.h>
32 #include <linux/nfsd_idmap.h>
33 #include <linux/lockd/bind.h>
34 #include <linux/sunrpc/svc.h>
35 #include <linux/sunrpc/svcsock.h>
36 #include <linux/nfsd/nfsd.h>
37 #include <linux/nfsd/cache.h>
38 #include <linux/nfsd/xdr.h>
39 #include <linux/nfsd/syscall.h>
40 #include <linux/lockd/lockd.h>
41 
42 #include <asm/uaccess.h>
43 #include <net/ipv6.h>
44 
45 /*
46  *	We have a single directory with 9 nodes in it.
47  */
48 enum {
49 	NFSD_Root = 1,
50 	NFSD_Svc,
51 	NFSD_Add,
52 	NFSD_Del,
53 	NFSD_Export,
54 	NFSD_Unexport,
55 	NFSD_Getfd,
56 	NFSD_Getfs,
57 	NFSD_List,
58 	NFSD_Fh,
59 	NFSD_FO_UnlockIP,
60 	NFSD_FO_UnlockFS,
61 	NFSD_Threads,
62 	NFSD_Pool_Threads,
63 	NFSD_Versions,
64 	NFSD_Ports,
65 	NFSD_MaxBlkSize,
66 	/*
67 	 * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
68 	 * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
69 	 */
70 #ifdef CONFIG_NFSD_V4
71 	NFSD_Leasetime,
72 	NFSD_RecoveryDir,
73 #endif
74 };
75 
76 /*
77  * write() for these nodes.
78  */
79 static ssize_t write_svc(struct file *file, char *buf, size_t size);
80 static ssize_t write_add(struct file *file, char *buf, size_t size);
81 static ssize_t write_del(struct file *file, char *buf, size_t size);
82 static ssize_t write_export(struct file *file, char *buf, size_t size);
83 static ssize_t write_unexport(struct file *file, char *buf, size_t size);
84 static ssize_t write_getfd(struct file *file, char *buf, size_t size);
85 static ssize_t write_getfs(struct file *file, char *buf, size_t size);
86 static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
87 static ssize_t write_threads(struct file *file, char *buf, size_t size);
88 static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
89 static ssize_t write_versions(struct file *file, char *buf, size_t size);
90 static ssize_t write_ports(struct file *file, char *buf, size_t size);
91 static ssize_t write_maxblksize(struct file *file, char *buf, size_t size);
92 #ifdef CONFIG_NFSD_V4
93 static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
94 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
95 #endif
96 
97 static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size);
98 static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size);
99 
100 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
101 	[NFSD_Svc] = write_svc,
102 	[NFSD_Add] = write_add,
103 	[NFSD_Del] = write_del,
104 	[NFSD_Export] = write_export,
105 	[NFSD_Unexport] = write_unexport,
106 	[NFSD_Getfd] = write_getfd,
107 	[NFSD_Getfs] = write_getfs,
108 	[NFSD_Fh] = write_filehandle,
109 	[NFSD_FO_UnlockIP] = failover_unlock_ip,
110 	[NFSD_FO_UnlockFS] = failover_unlock_fs,
111 	[NFSD_Threads] = write_threads,
112 	[NFSD_Pool_Threads] = write_pool_threads,
113 	[NFSD_Versions] = write_versions,
114 	[NFSD_Ports] = write_ports,
115 	[NFSD_MaxBlkSize] = write_maxblksize,
116 #ifdef CONFIG_NFSD_V4
117 	[NFSD_Leasetime] = write_leasetime,
118 	[NFSD_RecoveryDir] = write_recoverydir,
119 #endif
120 };
121 
122 static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
123 {
124 	ino_t ino =  file->f_path.dentry->d_inode->i_ino;
125 	char *data;
126 	ssize_t rv;
127 
128 	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
129 		return -EINVAL;
130 
131 	data = simple_transaction_get(file, buf, size);
132 	if (IS_ERR(data))
133 		return PTR_ERR(data);
134 
135 	rv =  write_op[ino](file, data, size);
136 	if (rv >= 0) {
137 		simple_transaction_set(file, rv);
138 		rv = size;
139 	}
140 	return rv;
141 }
142 
143 static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
144 {
145 	if (! file->private_data) {
146 		/* An attempt to read a transaction file without writing
147 		 * causes a 0-byte write so that the file can return
148 		 * state information
149 		 */
150 		ssize_t rv = nfsctl_transaction_write(file, buf, 0, pos);
151 		if (rv < 0)
152 			return rv;
153 	}
154 	return simple_transaction_read(file, buf, size, pos);
155 }
156 
157 static const struct file_operations transaction_ops = {
158 	.write		= nfsctl_transaction_write,
159 	.read		= nfsctl_transaction_read,
160 	.release	= simple_transaction_release,
161 };
162 
163 static int exports_open(struct inode *inode, struct file *file)
164 {
165 	return seq_open(file, &nfs_exports_op);
166 }
167 
168 static const struct file_operations exports_operations = {
169 	.open		= exports_open,
170 	.read		= seq_read,
171 	.llseek		= seq_lseek,
172 	.release	= seq_release,
173 	.owner		= THIS_MODULE,
174 };
175 
176 /*----------------------------------------------------------------------------*/
177 /*
178  * payload - write methods
179  * If the method has a response, the response should be put in buf,
180  * and the length returned.  Otherwise return 0 or and -error.
181  */
182 
183 static ssize_t write_svc(struct file *file, char *buf, size_t size)
184 {
185 	struct nfsctl_svc *data;
186 	if (size < sizeof(*data))
187 		return -EINVAL;
188 	data = (struct nfsctl_svc*) buf;
189 	return nfsd_svc(data->svc_port, data->svc_nthreads);
190 }
191 
192 static ssize_t write_add(struct file *file, char *buf, size_t size)
193 {
194 	struct nfsctl_client *data;
195 	if (size < sizeof(*data))
196 		return -EINVAL;
197 	data = (struct nfsctl_client *)buf;
198 	return exp_addclient(data);
199 }
200 
201 static ssize_t write_del(struct file *file, char *buf, size_t size)
202 {
203 	struct nfsctl_client *data;
204 	if (size < sizeof(*data))
205 		return -EINVAL;
206 	data = (struct nfsctl_client *)buf;
207 	return exp_delclient(data);
208 }
209 
210 static ssize_t write_export(struct file *file, char *buf, size_t size)
211 {
212 	struct nfsctl_export *data;
213 	if (size < sizeof(*data))
214 		return -EINVAL;
215 	data = (struct nfsctl_export*)buf;
216 	return exp_export(data);
217 }
218 
219 static ssize_t write_unexport(struct file *file, char *buf, size_t size)
220 {
221 	struct nfsctl_export *data;
222 
223 	if (size < sizeof(*data))
224 		return -EINVAL;
225 	data = (struct nfsctl_export*)buf;
226 	return exp_unexport(data);
227 }
228 
229 static ssize_t write_getfs(struct file *file, char *buf, size_t size)
230 {
231 	struct nfsctl_fsparm *data;
232 	struct sockaddr_in *sin;
233 	struct auth_domain *clp;
234 	int err = 0;
235 	struct knfsd_fh *res;
236 	struct in6_addr in6;
237 
238 	if (size < sizeof(*data))
239 		return -EINVAL;
240 	data = (struct nfsctl_fsparm*)buf;
241 	err = -EPROTONOSUPPORT;
242 	if (data->gd_addr.sa_family != AF_INET)
243 		goto out;
244 	sin = (struct sockaddr_in *)&data->gd_addr;
245 	if (data->gd_maxlen > NFS3_FHSIZE)
246 		data->gd_maxlen = NFS3_FHSIZE;
247 
248 	res = (struct knfsd_fh*)buf;
249 
250 	exp_readlock();
251 
252 	ipv6_addr_set_v4mapped(sin->sin_addr.s_addr, &in6);
253 
254 	clp = auth_unix_lookup(&in6);
255 	if (!clp)
256 		err = -EPERM;
257 	else {
258 		err = exp_rootfh(clp, data->gd_path, res, data->gd_maxlen);
259 		auth_domain_put(clp);
260 	}
261 	exp_readunlock();
262 	if (err == 0)
263 		err = res->fh_size + offsetof(struct knfsd_fh, fh_base);
264  out:
265 	return err;
266 }
267 
268 static ssize_t write_getfd(struct file *file, char *buf, size_t size)
269 {
270 	struct nfsctl_fdparm *data;
271 	struct sockaddr_in *sin;
272 	struct auth_domain *clp;
273 	int err = 0;
274 	struct knfsd_fh fh;
275 	char *res;
276 	struct in6_addr in6;
277 
278 	if (size < sizeof(*data))
279 		return -EINVAL;
280 	data = (struct nfsctl_fdparm*)buf;
281 	err = -EPROTONOSUPPORT;
282 	if (data->gd_addr.sa_family != AF_INET)
283 		goto out;
284 	err = -EINVAL;
285 	if (data->gd_version < 2 || data->gd_version > NFSSVC_MAXVERS)
286 		goto out;
287 
288 	res = buf;
289 	sin = (struct sockaddr_in *)&data->gd_addr;
290 	exp_readlock();
291 
292 	ipv6_addr_set_v4mapped(sin->sin_addr.s_addr, &in6);
293 
294 	clp = auth_unix_lookup(&in6);
295 	if (!clp)
296 		err = -EPERM;
297 	else {
298 		err = exp_rootfh(clp, data->gd_path, &fh, NFS_FHSIZE);
299 		auth_domain_put(clp);
300 	}
301 	exp_readunlock();
302 
303 	if (err == 0) {
304 		memset(res,0, NFS_FHSIZE);
305 		memcpy(res, &fh.fh_base, fh.fh_size);
306 		err = NFS_FHSIZE;
307 	}
308  out:
309 	return err;
310 }
311 
312 static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size)
313 {
314 	struct sockaddr_in sin = {
315 		.sin_family	= AF_INET,
316 	};
317 	int b1, b2, b3, b4;
318 	char c;
319 	char *fo_path;
320 
321 	/* sanity check */
322 	if (size == 0)
323 		return -EINVAL;
324 
325 	if (buf[size-1] != '\n')
326 		return -EINVAL;
327 
328 	fo_path = buf;
329 	if (qword_get(&buf, fo_path, size) < 0)
330 		return -EINVAL;
331 
332 	/* get ipv4 address */
333 	if (sscanf(fo_path, NIPQUAD_FMT "%c", &b1, &b2, &b3, &b4, &c) != 4)
334 		return -EINVAL;
335 	if (b1 > 255 || b2 > 255 || b3 > 255 || b4 > 255)
336 		return -EINVAL;
337 	sin.sin_addr.s_addr = htonl((b1 << 24) | (b2 << 16) | (b3 << 8) | b4);
338 
339 	return nlmsvc_unlock_all_by_ip((struct sockaddr *)&sin);
340 }
341 
342 static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size)
343 {
344 	struct path path;
345 	char *fo_path;
346 	int error;
347 
348 	/* sanity check */
349 	if (size == 0)
350 		return -EINVAL;
351 
352 	if (buf[size-1] != '\n')
353 		return -EINVAL;
354 
355 	fo_path = buf;
356 	if (qword_get(&buf, fo_path, size) < 0)
357 		return -EINVAL;
358 
359 	error = kern_path(fo_path, 0, &path);
360 	if (error)
361 		return error;
362 
363 	error = nlmsvc_unlock_all_by_sb(path.mnt->mnt_sb);
364 
365 	path_put(&path);
366 	return error;
367 }
368 
369 static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
370 {
371 	/* request is:
372 	 *   domain path maxsize
373 	 * response is
374 	 *   filehandle
375 	 *
376 	 * qword quoting is used, so filehandle will be \x....
377 	 */
378 	char *dname, *path;
379 	int uninitialized_var(maxsize);
380 	char *mesg = buf;
381 	int len;
382 	struct auth_domain *dom;
383 	struct knfsd_fh fh;
384 
385 	if (size == 0)
386 		return -EINVAL;
387 
388 	if (buf[size-1] != '\n')
389 		return -EINVAL;
390 	buf[size-1] = 0;
391 
392 	dname = mesg;
393 	len = qword_get(&mesg, dname, size);
394 	if (len <= 0) return -EINVAL;
395 
396 	path = dname+len+1;
397 	len = qword_get(&mesg, path, size);
398 	if (len <= 0) return -EINVAL;
399 
400 	len = get_int(&mesg, &maxsize);
401 	if (len)
402 		return len;
403 
404 	if (maxsize < NFS_FHSIZE)
405 		return -EINVAL;
406 	if (maxsize > NFS3_FHSIZE)
407 		maxsize = NFS3_FHSIZE;
408 
409 	if (qword_get(&mesg, mesg, size)>0)
410 		return -EINVAL;
411 
412 	/* we have all the words, they are in buf.. */
413 	dom = unix_domain_find(dname);
414 	if (!dom)
415 		return -ENOMEM;
416 
417 	len = exp_rootfh(dom, path, &fh,  maxsize);
418 	auth_domain_put(dom);
419 	if (len)
420 		return len;
421 
422 	mesg = buf; len = SIMPLE_TRANSACTION_LIMIT;
423 	qword_addhex(&mesg, &len, (char*)&fh.fh_base, fh.fh_size);
424 	mesg[-1] = '\n';
425 	return mesg - buf;
426 }
427 
428 static ssize_t write_threads(struct file *file, char *buf, size_t size)
429 {
430 	/* if size > 0, look for a number of threads and call nfsd_svc
431 	 * then write out number of threads as reply
432 	 */
433 	char *mesg = buf;
434 	int rv;
435 	if (size > 0) {
436 		int newthreads;
437 		rv = get_int(&mesg, &newthreads);
438 		if (rv)
439 			return rv;
440 		if (newthreads <0)
441 			return -EINVAL;
442 		rv = nfsd_svc(2049, newthreads);
443 		if (rv)
444 			return rv;
445 	}
446 	sprintf(buf, "%d\n", nfsd_nrthreads());
447 	return strlen(buf);
448 }
449 
450 static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
451 {
452 	/* if size > 0, look for an array of number of threads per node
453 	 * and apply them  then write out number of threads per node as reply
454 	 */
455 	char *mesg = buf;
456 	int i;
457 	int rv;
458 	int len;
459 	int npools;
460 	int *nthreads;
461 
462 	mutex_lock(&nfsd_mutex);
463 	npools = nfsd_nrpools();
464 	if (npools == 0) {
465 		/*
466 		 * NFS is shut down.  The admin can start it by
467 		 * writing to the threads file but NOT the pool_threads
468 		 * file, sorry.  Report zero threads.
469 		 */
470 		mutex_unlock(&nfsd_mutex);
471 		strcpy(buf, "0\n");
472 		return strlen(buf);
473 	}
474 
475 	nthreads = kcalloc(npools, sizeof(int), GFP_KERNEL);
476 	rv = -ENOMEM;
477 	if (nthreads == NULL)
478 		goto out_free;
479 
480 	if (size > 0) {
481 		for (i = 0; i < npools; i++) {
482 			rv = get_int(&mesg, &nthreads[i]);
483 			if (rv == -ENOENT)
484 				break;		/* fewer numbers than pools */
485 			if (rv)
486 				goto out_free;	/* syntax error */
487 			rv = -EINVAL;
488 			if (nthreads[i] < 0)
489 				goto out_free;
490 		}
491 		rv = nfsd_set_nrthreads(i, nthreads);
492 		if (rv)
493 			goto out_free;
494 	}
495 
496 	rv = nfsd_get_nrthreads(npools, nthreads);
497 	if (rv)
498 		goto out_free;
499 
500 	mesg = buf;
501 	size = SIMPLE_TRANSACTION_LIMIT;
502 	for (i = 0; i < npools && size > 0; i++) {
503 		snprintf(mesg, size, "%d%c", nthreads[i], (i == npools-1 ? '\n' : ' '));
504 		len = strlen(mesg);
505 		size -= len;
506 		mesg += len;
507 	}
508 
509 	mutex_unlock(&nfsd_mutex);
510 	return (mesg-buf);
511 
512 out_free:
513 	kfree(nthreads);
514 	mutex_unlock(&nfsd_mutex);
515 	return rv;
516 }
517 
518 static ssize_t __write_versions(struct file *file, char *buf, size_t size)
519 {
520 	/*
521 	 * Format:
522 	 *   [-/+]vers [-/+]vers ...
523 	 */
524 	char *mesg = buf;
525 	char *vers, sign;
526 	int len, num;
527 	ssize_t tlen = 0;
528 	char *sep;
529 
530 	if (size>0) {
531 		if (nfsd_serv)
532 			/* Cannot change versions without updating
533 			 * nfsd_serv->sv_xdrsize, and reallocing
534 			 * rq_argp and rq_resp
535 			 */
536 			return -EBUSY;
537 		if (buf[size-1] != '\n')
538 			return -EINVAL;
539 		buf[size-1] = 0;
540 
541 		vers = mesg;
542 		len = qword_get(&mesg, vers, size);
543 		if (len <= 0) return -EINVAL;
544 		do {
545 			sign = *vers;
546 			if (sign == '+' || sign == '-')
547 				num = simple_strtol((vers+1), NULL, 0);
548 			else
549 				num = simple_strtol(vers, NULL, 0);
550 			switch(num) {
551 			case 2:
552 			case 3:
553 			case 4:
554 				nfsd_vers(num, sign == '-' ? NFSD_CLEAR : NFSD_SET);
555 				break;
556 			default:
557 				return -EINVAL;
558 			}
559 			vers += len + 1;
560 			tlen += len;
561 		} while ((len = qword_get(&mesg, vers, size)) > 0);
562 		/* If all get turned off, turn them back on, as
563 		 * having no versions is BAD
564 		 */
565 		nfsd_reset_versions();
566 	}
567 	/* Now write current state into reply buffer */
568 	len = 0;
569 	sep = "";
570 	for (num=2 ; num <= 4 ; num++)
571 		if (nfsd_vers(num, NFSD_AVAIL)) {
572 			len += sprintf(buf+len, "%s%c%d", sep,
573 				       nfsd_vers(num, NFSD_TEST)?'+':'-',
574 				       num);
575 			sep = " ";
576 		}
577 	len += sprintf(buf+len, "\n");
578 	return len;
579 }
580 
581 static ssize_t write_versions(struct file *file, char *buf, size_t size)
582 {
583 	ssize_t rv;
584 
585 	mutex_lock(&nfsd_mutex);
586 	rv = __write_versions(file, buf, size);
587 	mutex_unlock(&nfsd_mutex);
588 	return rv;
589 }
590 
591 static ssize_t __write_ports(struct file *file, char *buf, size_t size)
592 {
593 	if (size == 0) {
594 		int len = 0;
595 
596 		if (nfsd_serv)
597 			len = svc_xprt_names(nfsd_serv, buf, 0);
598 		return len;
599 	}
600 	/* Either a single 'fd' number is written, in which
601 	 * case it must be for a socket of a supported family/protocol,
602 	 * and we use it as an nfsd socket, or
603 	 * A '-' followed by the 'name' of a socket in which case
604 	 * we close the socket.
605 	 */
606 	if (isdigit(buf[0])) {
607 		char *mesg = buf;
608 		int fd;
609 		int err;
610 		err = get_int(&mesg, &fd);
611 		if (err)
612 			return -EINVAL;
613 		if (fd < 0)
614 			return -EINVAL;
615 		err = nfsd_create_serv();
616 		if (!err) {
617 			err = svc_addsock(nfsd_serv, fd, buf);
618 			if (err >= 0) {
619 				err = lockd_up();
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