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[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / nfsd / export.c
blob4e0578121d9a621f0d36737582140e4573c464db
1 #define MSNFS /* HACK HACK */
2 /*
3 * linux/fs/nfsd/export.c
5 * NFS exporting and validation.
7 * We maintain a list of clients, each of which has a list of
8 * exports. To export an fs to a given client, you first have
9 * to create the client entry with NFSCTL_ADDCLIENT, which
10 * creates a client control block and adds it to the hash
11 * table. Then, you call NFSCTL_EXPORT for each fs.
14 * Copyright (C) 1995, 1996 Olaf Kirch, <okir@monad.swb.de>
17 #include <linux/unistd.h>
18 #include <linux/slab.h>
19 #include <linux/sched.h>
20 #include <linux/stat.h>
21 #include <linux/in.h>
22 #include <linux/seq_file.h>
23 #include <linux/syscalls.h>
24 #include <linux/rwsem.h>
25 #include <linux/dcache.h>
26 #include <linux/namei.h>
27 #include <linux/mount.h>
28 #include <linux/hash.h>
29 #include <linux/module.h>
31 #include <linux/sunrpc/svc.h>
32 #include <linux/nfsd/nfsd.h>
33 #include <linux/nfsd/nfsfh.h>
34 #include <linux/nfsd/syscall.h>
35 #include <linux/lockd/bind.h>
37 #define NFSDDBG_FACILITY NFSDDBG_EXPORT
38 #define NFSD_PARANOIA 1
40 typedef struct auth_domain svc_client;
41 typedef struct svc_export svc_export;
43 static void exp_do_unexport(svc_export *unexp);
44 static int exp_verify_string(char *cp, int max);
47 * We have two caches.
48 * One maps client+vfsmnt+dentry to export options - the export map
49 * The other maps client+filehandle-fragment to export options. - the expkey map
51 * The export options are actually stored in the first map, and the
52 * second map contains a reference to the entry in the first map.
55 #define EXPKEY_HASHBITS 8
56 #define EXPKEY_HASHMAX (1 << EXPKEY_HASHBITS)
57 #define EXPKEY_HASHMASK (EXPKEY_HASHMAX -1)
58 static struct cache_head *expkey_table[EXPKEY_HASHMAX];
60 static void expkey_put(struct kref *ref)
62 struct svc_expkey *key = container_of(ref, struct svc_expkey, h.ref);
64 if (test_bit(CACHE_VALID, &key->h.flags) &&
65 !test_bit(CACHE_NEGATIVE, &key->h.flags)) {
66 dput(key->ek_dentry);
67 mntput(key->ek_mnt);
69 auth_domain_put(key->ek_client);
70 kfree(key);
73 static void expkey_request(struct cache_detail *cd,
74 struct cache_head *h,
75 char **bpp, int *blen)
77 /* client fsidtype \xfsid */
78 struct svc_expkey *ek = container_of(h, struct svc_expkey, h);
79 char type[5];
81 qword_add(bpp, blen, ek->ek_client->name);
82 snprintf(type, 5, "%d", ek->ek_fsidtype);
83 qword_add(bpp, blen, type);
84 qword_addhex(bpp, blen, (char*)ek->ek_fsid, key_len(ek->ek_fsidtype));
85 (*bpp)[-1] = '\n';
88 static struct svc_expkey *svc_expkey_update(struct svc_expkey *new, struct svc_expkey *old);
89 static struct svc_expkey *svc_expkey_lookup(struct svc_expkey *);
90 static struct cache_detail svc_expkey_cache;
92 static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)
94 /* client fsidtype fsid [path] */
95 char *buf;
96 int len;
97 struct auth_domain *dom = NULL;
98 int err;
99 int fsidtype;
100 char *ep;
101 struct svc_expkey key;
102 struct svc_expkey *ek;
104 if (mesg[mlen-1] != '\n')
105 return -EINVAL;
106 mesg[mlen-1] = 0;
108 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
109 err = -ENOMEM;
110 if (!buf) goto out;
112 err = -EINVAL;
113 if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
114 goto out;
116 err = -ENOENT;
117 dom = auth_domain_find(buf);
118 if (!dom)
119 goto out;
120 dprintk("found domain %s\n", buf);
122 err = -EINVAL;
123 if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
124 goto out;
125 fsidtype = simple_strtoul(buf, &ep, 10);
126 if (*ep)
127 goto out;
128 dprintk("found fsidtype %d\n", fsidtype);
129 if (fsidtype > 2)
130 goto out;
131 if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
132 goto out;
133 dprintk("found fsid length %d\n", len);
134 if (len != key_len(fsidtype))
135 goto out;
137 /* OK, we seem to have a valid key */
138 key.h.flags = 0;
139 key.h.expiry_time = get_expiry(&mesg);
140 if (key.h.expiry_time == 0)
141 goto out;
143 key.ek_client = dom;
144 key.ek_fsidtype = fsidtype;
145 memcpy(key.ek_fsid, buf, len);
147 ek = svc_expkey_lookup(&key);
148 err = -ENOMEM;
149 if (!ek)
150 goto out;
152 /* now we want a pathname, or empty meaning NEGATIVE */
153 err = -EINVAL;
154 if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0)
155 goto out;
156 dprintk("Path seems to be <%s>\n", buf);
157 err = 0;
158 if (len == 0) {
159 set_bit(CACHE_NEGATIVE, &key.h.flags);
160 ek = svc_expkey_update(&key, ek);
161 if (ek)
162 cache_put(&ek->h, &svc_expkey_cache);
163 else err = -ENOMEM;
164 } else {
165 struct nameidata nd;
166 err = path_lookup(buf, 0, &nd);
167 if (err)
168 goto out;
170 dprintk("Found the path %s\n", buf);
171 key.ek_mnt = nd.mnt;
172 key.ek_dentry = nd.dentry;
174 ek = svc_expkey_update(&key, ek);
175 if (ek)
176 cache_put(&ek->h, &svc_expkey_cache);
177 else
178 err = -ENOMEM;
179 path_release(&nd);
181 cache_flush();
182 out:
183 if (dom)
184 auth_domain_put(dom);
185 kfree(buf);
186 return err;
189 static int expkey_show(struct seq_file *m,
190 struct cache_detail *cd,
191 struct cache_head *h)
193 struct svc_expkey *ek ;
195 if (h ==NULL) {
196 seq_puts(m, "#domain fsidtype fsid [path]\n");
197 return 0;
199 ek = container_of(h, struct svc_expkey, h);
200 seq_printf(m, "%s %d 0x%08x", ek->ek_client->name,
201 ek->ek_fsidtype, ek->ek_fsid[0]);
202 if (ek->ek_fsidtype != 1)
203 seq_printf(m, "%08x", ek->ek_fsid[1]);
204 if (ek->ek_fsidtype == 2)
205 seq_printf(m, "%08x", ek->ek_fsid[2]);
206 if (test_bit(CACHE_VALID, &h->flags) &&
207 !test_bit(CACHE_NEGATIVE, &h->flags)) {
208 seq_printf(m, " ");
209 seq_path(m, ek->ek_mnt, ek->ek_dentry, "\\ \t\n");
211 seq_printf(m, "\n");
212 return 0;
215 static inline int expkey_match (struct cache_head *a, struct cache_head *b)
217 struct svc_expkey *orig = container_of(a, struct svc_expkey, h);
218 struct svc_expkey *new = container_of(b, struct svc_expkey, h);
220 if (orig->ek_fsidtype != new->ek_fsidtype ||
221 orig->ek_client != new->ek_client ||
222 memcmp(orig->ek_fsid, new->ek_fsid, key_len(orig->ek_fsidtype)) != 0)
223 return 0;
224 return 1;
227 static inline void expkey_init(struct cache_head *cnew,
228 struct cache_head *citem)
230 struct svc_expkey *new = container_of(cnew, struct svc_expkey, h);
231 struct svc_expkey *item = container_of(citem, struct svc_expkey, h);
233 kref_get(&item->ek_client->ref);
234 new->ek_client = item->ek_client;
235 new->ek_fsidtype = item->ek_fsidtype;
236 new->ek_fsid[0] = item->ek_fsid[0];
237 new->ek_fsid[1] = item->ek_fsid[1];
238 new->ek_fsid[2] = item->ek_fsid[2];
241 static inline void expkey_update(struct cache_head *cnew,
242 struct cache_head *citem)
244 struct svc_expkey *new = container_of(cnew, struct svc_expkey, h);
245 struct svc_expkey *item = container_of(citem, struct svc_expkey, h);
247 new->ek_mnt = mntget(item->ek_mnt);
248 new->ek_dentry = dget(item->ek_dentry);
251 static struct cache_head *expkey_alloc(void)
253 struct svc_expkey *i = kmalloc(sizeof(*i), GFP_KERNEL);
254 if (i)
255 return &i->h;
256 else
257 return NULL;
260 static struct cache_detail svc_expkey_cache = {
261 .owner = THIS_MODULE,
262 .hash_size = EXPKEY_HASHMAX,
263 .hash_table = expkey_table,
264 .name = "nfsd.fh",
265 .cache_put = expkey_put,
266 .cache_request = expkey_request,
267 .cache_parse = expkey_parse,
268 .cache_show = expkey_show,
269 .match = expkey_match,
270 .init = expkey_init,
271 .update = expkey_update,
272 .alloc = expkey_alloc,
275 static struct svc_expkey *
276 svc_expkey_lookup(struct svc_expkey *item)
278 struct cache_head *ch;
279 int hash = item->ek_fsidtype;
280 char * cp = (char*)item->ek_fsid;
281 int len = key_len(item->ek_fsidtype);
283 hash ^= hash_mem(cp, len, EXPKEY_HASHBITS);
284 hash ^= hash_ptr(item->ek_client, EXPKEY_HASHBITS);
285 hash &= EXPKEY_HASHMASK;
287 ch = sunrpc_cache_lookup(&svc_expkey_cache, &item->h,
288 hash);
289 if (ch)
290 return container_of(ch, struct svc_expkey, h);
291 else
292 return NULL;
295 static struct svc_expkey *
296 svc_expkey_update(struct svc_expkey *new, struct svc_expkey *old)
298 struct cache_head *ch;
299 int hash = new->ek_fsidtype;
300 char * cp = (char*)new->ek_fsid;
301 int len = key_len(new->ek_fsidtype);
303 hash ^= hash_mem(cp, len, EXPKEY_HASHBITS);
304 hash ^= hash_ptr(new->ek_client, EXPKEY_HASHBITS);
305 hash &= EXPKEY_HASHMASK;
307 ch = sunrpc_cache_update(&svc_expkey_cache, &new->h,
308 &old->h, hash);
309 if (ch)
310 return container_of(ch, struct svc_expkey, h);
311 else
312 return NULL;
316 #define EXPORT_HASHBITS 8
317 #define EXPORT_HASHMAX (1<< EXPORT_HASHBITS)
318 #define EXPORT_HASHMASK (EXPORT_HASHMAX -1)
320 static struct cache_head *export_table[EXPORT_HASHMAX];
322 static void svc_export_put(struct kref *ref)
324 struct svc_export *exp = container_of(ref, struct svc_export, h.ref);
325 dput(exp->ex_dentry);
326 mntput(exp->ex_mnt);
327 auth_domain_put(exp->ex_client);
328 kfree(exp);
331 static void svc_export_request(struct cache_detail *cd,
332 struct cache_head *h,
333 char **bpp, int *blen)
335 /* client path */
336 struct svc_export *exp = container_of(h, struct svc_export, h);
337 char *pth;
339 qword_add(bpp, blen, exp->ex_client->name);
340 pth = d_path(exp->ex_dentry, exp->ex_mnt, *bpp, *blen);
341 if (IS_ERR(pth)) {
342 /* is this correct? */
343 (*bpp)[0] = '\n';
344 return;
346 qword_add(bpp, blen, pth);
347 (*bpp)[-1] = '\n';
350 static struct svc_export *svc_export_update(struct svc_export *new,
351 struct svc_export *old);
352 static struct svc_export *svc_export_lookup(struct svc_export *);
354 static int check_export(struct inode *inode, int flags)
357 /* We currently export only dirs and regular files.
358 * This is what umountd does.
360 if (!S_ISDIR(inode->i_mode) &&
361 !S_ISREG(inode->i_mode))
362 return -ENOTDIR;
364 /* There are two requirements on a filesystem to be exportable.
365 * 1: We must be able to identify the filesystem from a number.
366 * either a device number (so FS_REQUIRES_DEV needed)
367 * or an FSID number (so NFSEXP_FSID needed).
368 * 2: We must be able to find an inode from a filehandle.
369 * This means that s_export_op must be set.
371 if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&
372 !(flags & NFSEXP_FSID)) {
373 dprintk("exp_export: export of non-dev fs without fsid");
374 return -EINVAL;
376 if (!inode->i_sb->s_export_op) {
377 dprintk("exp_export: export of invalid fs type.\n");
378 return -EINVAL;
381 /* Ok, we can export it */;
382 if (!inode->i_sb->s_export_op->find_exported_dentry)
383 inode->i_sb->s_export_op->find_exported_dentry =
384 find_exported_dentry;
385 return 0;
389 static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
391 /* client path expiry [flags anonuid anongid fsid] */
392 char *buf;
393 int len;
394 int err;
395 struct auth_domain *dom = NULL;
396 struct nameidata nd;
397 struct svc_export exp, *expp;
398 int an_int;
400 nd.dentry = NULL;
402 if (mesg[mlen-1] != '\n')
403 return -EINVAL;
404 mesg[mlen-1] = 0;
406 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
407 err = -ENOMEM;
408 if (!buf) goto out;
410 /* client */
411 len = qword_get(&mesg, buf, PAGE_SIZE);
412 err = -EINVAL;
413 if (len <= 0) goto out;
415 err = -ENOENT;
416 dom = auth_domain_find(buf);
417 if (!dom)
418 goto out;
420 /* path */
421 err = -EINVAL;
422 if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
423 goto out;
424 err = path_lookup(buf, 0, &nd);
425 if (err) goto out_no_path;
427 exp.h.flags = 0;
428 exp.ex_client = dom;
429 exp.ex_mnt = nd.mnt;
430 exp.ex_dentry = nd.dentry;
432 /* expiry */
433 err = -EINVAL;
434 exp.h.expiry_time = get_expiry(&mesg);
435 if (exp.h.expiry_time == 0)
436 goto out;
438 /* flags */
439 err = get_int(&mesg, &an_int);
440 if (err == -ENOENT)
441 set_bit(CACHE_NEGATIVE, &exp.h.flags);
442 else {
443 if (err || an_int < 0) goto out;
444 exp.ex_flags= an_int;
446 /* anon uid */
447 err = get_int(&mesg, &an_int);
448 if (err) goto out;
449 exp.ex_anon_uid= an_int;
451 /* anon gid */
452 err = get_int(&mesg, &an_int);
453 if (err) goto out;
454 exp.ex_anon_gid= an_int;
456 /* fsid */
457 err = get_int(&mesg, &an_int);
458 if (err) goto out;
459 exp.ex_fsid = an_int;
461 err = check_export(nd.dentry->d_inode, exp.ex_flags);
462 if (err) goto out;
465 expp = svc_export_lookup(&exp);
466 if (expp)
467 expp = svc_export_update(&exp, expp);
468 else
469 err = -ENOMEM;
470 cache_flush();
471 if (expp == NULL)
472 err = -ENOMEM;
473 else
474 exp_put(expp);
475 out:
476 if (nd.dentry)
477 path_release(&nd);
478 out_no_path:
479 if (dom)
480 auth_domain_put(dom);
481 kfree(buf);
482 return err;
485 static void exp_flags(struct seq_file *m, int flag, int fsid, uid_t anonu, uid_t anong);
487 static int svc_export_show(struct seq_file *m,
488 struct cache_detail *cd,
489 struct cache_head *h)
491 struct svc_export *exp ;
493 if (h ==NULL) {
494 seq_puts(m, "#path domain(flags)\n");
495 return 0;
497 exp = container_of(h, struct svc_export, h);
498 seq_path(m, exp->ex_mnt, exp->ex_dentry, " \t\n\\");
499 seq_putc(m, '\t');
500 seq_escape(m, exp->ex_client->name, " \t\n\\");
501 seq_putc(m, '(');
502 if (test_bit(CACHE_VALID, &h->flags) &&
503 !test_bit(CACHE_NEGATIVE, &h->flags))
504 exp_flags(m, exp->ex_flags, exp->ex_fsid,
505 exp->ex_anon_uid, exp->ex_anon_gid);
506 seq_puts(m, ")\n");
507 return 0;
509 static int svc_export_match(struct cache_head *a, struct cache_head *b)
511 struct svc_export *orig = container_of(a, struct svc_export, h);
512 struct svc_export *new = container_of(b, struct svc_export, h);
513 return orig->ex_client == new->ex_client &&
514 orig->ex_dentry == new->ex_dentry &&
515 orig->ex_mnt == new->ex_mnt;
518 static void svc_export_init(struct cache_head *cnew, struct cache_head *citem)
520 struct svc_export *new = container_of(cnew, struct svc_export, h);
521 struct svc_export *item = container_of(citem, struct svc_export, h);
523 kref_get(&item->ex_client->ref);
524 new->ex_client = item->ex_client;
525 new->ex_dentry = dget(item->ex_dentry);
526 new->ex_mnt = mntget(item->ex_mnt);
529 static void export_update(struct cache_head *cnew, struct cache_head *citem)
531 struct svc_export *new = container_of(cnew, struct svc_export, h);
532 struct svc_export *item = container_of(citem, struct svc_export, h);
534 new->ex_flags = item->ex_flags;
535 new->ex_anon_uid = item->ex_anon_uid;
536 new->ex_anon_gid = item->ex_anon_gid;
537 new->ex_fsid = item->ex_fsid;
540 static struct cache_head *svc_export_alloc(void)
542 struct svc_export *i = kmalloc(sizeof(*i), GFP_KERNEL);
543 if (i)
544 return &i->h;
545 else
546 return NULL;
549 struct cache_detail svc_export_cache = {
550 .owner = THIS_MODULE,
551 .hash_size = EXPORT_HASHMAX,
552 .hash_table = export_table,
553 .name = "nfsd.export",
554 .cache_put = svc_export_put,
555 .cache_request = svc_export_request,
556 .cache_parse = svc_export_parse,
557 .cache_show = svc_export_show,
558 .match = svc_export_match,
559 .init = svc_export_init,
560 .update = export_update,
561 .alloc = svc_export_alloc,
564 static struct svc_export *
565 svc_export_lookup(struct svc_export *exp)
567 struct cache_head *ch;
568 int hash;
569 hash = hash_ptr(exp->ex_client, EXPORT_HASHBITS);
570 hash ^= hash_ptr(exp->ex_dentry, EXPORT_HASHBITS);
571 hash ^= hash_ptr(exp->ex_mnt, EXPORT_HASHBITS);
573 ch = sunrpc_cache_lookup(&svc_export_cache, &exp->h,
574 hash);
575 if (ch)
576 return container_of(ch, struct svc_export, h);
577 else
578 return NULL;
581 static struct svc_export *
582 svc_export_update(struct svc_export *new, struct svc_export *old)
584 struct cache_head *ch;
585 int hash;
586 hash = hash_ptr(old->ex_client, EXPORT_HASHBITS);
587 hash ^= hash_ptr(old->ex_dentry, EXPORT_HASHBITS);
588 hash ^= hash_ptr(old->ex_mnt, EXPORT_HASHBITS);
590 ch = sunrpc_cache_update(&svc_export_cache, &new->h,
591 &old->h,
592 hash);
593 if (ch)
594 return container_of(ch, struct svc_export, h);
595 else
596 return NULL;
600 static struct svc_expkey *
601 exp_find_key(svc_client *clp, int fsid_type, u32 *fsidv, struct cache_req *reqp)
603 struct svc_expkey key, *ek;
604 int err;
606 if (!clp)
607 return NULL;
609 key.ek_client = clp;
610 key.ek_fsidtype = fsid_type;
611 memcpy(key.ek_fsid, fsidv, key_len(fsid_type));
613 ek = svc_expkey_lookup(&key);
614 if (ek != NULL)
615 if ((err = cache_check(&svc_expkey_cache, &ek->h, reqp)))
616 ek = ERR_PTR(err);
617 return ek;
620 static int exp_set_key(svc_client *clp, int fsid_type, u32 *fsidv,
621 struct svc_export *exp)
623 struct svc_expkey key, *ek;
625 key.ek_client = clp;
626 key.ek_fsidtype = fsid_type;
627 memcpy(key.ek_fsid, fsidv, key_len(fsid_type));
628 key.ek_mnt = exp->ex_mnt;
629 key.ek_dentry = exp->ex_dentry;
630 key.h.expiry_time = NEVER;
631 key.h.flags = 0;
633 ek = svc_expkey_lookup(&key);
634 if (ek)
635 ek = svc_expkey_update(&key,ek);
636 if (ek) {
637 cache_put(&ek->h, &svc_expkey_cache);
638 return 0;
640 return -ENOMEM;
644 * Find the client's export entry matching xdev/xino.
646 static inline struct svc_expkey *
647 exp_get_key(svc_client *clp, dev_t dev, ino_t ino)
649 u32 fsidv[3];
651 if (old_valid_dev(dev)) {
652 mk_fsid_v0(fsidv, dev, ino);
653 return exp_find_key(clp, 0, fsidv, NULL);
655 mk_fsid_v3(fsidv, dev, ino);
656 return exp_find_key(clp, 3, fsidv, NULL);
660 * Find the client's export entry matching fsid
662 static inline struct svc_expkey *
663 exp_get_fsid_key(svc_client *clp, int fsid)
665 u32 fsidv[2];
667 mk_fsid_v1(fsidv, fsid);
669 return exp_find_key(clp, 1, fsidv, NULL);
672 svc_export *
673 exp_get_by_name(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry,
674 struct cache_req *reqp)
676 struct svc_export *exp, key;
678 if (!clp)
679 return NULL;
681 key.ex_client = clp;
682 key.ex_mnt = mnt;
683 key.ex_dentry = dentry;
685 exp = svc_export_lookup(&key);
686 if (exp != NULL)
687 switch (cache_check(&svc_export_cache, &exp->h, reqp)) {
688 case 0: break;
689 case -EAGAIN:
690 exp = ERR_PTR(-EAGAIN);
691 break;
692 default:
693 exp = NULL;
696 return exp;
700 * Find the export entry for a given dentry.
702 struct svc_export *
703 exp_parent(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry,
704 struct cache_req *reqp)
706 svc_export *exp;
708 dget(dentry);
709 exp = exp_get_by_name(clp, mnt, dentry, reqp);
711 while (exp == NULL && !IS_ROOT(dentry)) {
712 struct dentry *parent;
714 parent = dget_parent(dentry);
715 dput(dentry);
716 dentry = parent;
717 exp = exp_get_by_name(clp, mnt, dentry, reqp);
719 dput(dentry);
720 return exp;
724 * Hashtable locking. Write locks are placed only by user processes
725 * wanting to modify export information.
726 * Write locking only done in this file. Read locking
727 * needed externally.
730 static DECLARE_RWSEM(hash_sem);
732 void
733 exp_readlock(void)
735 down_read(&hash_sem);
738 static inline void
739 exp_writelock(void)
741 down_write(&hash_sem);
744 void
745 exp_readunlock(void)
747 up_read(&hash_sem);
750 static inline void
751 exp_writeunlock(void)
753 up_write(&hash_sem);
756 static void exp_fsid_unhash(struct svc_export *exp)
758 struct svc_expkey *ek;
760 if ((exp->ex_flags & NFSEXP_FSID) == 0)
761 return;
763 ek = exp_get_fsid_key(exp->ex_client, exp->ex_fsid);
764 if (ek && !IS_ERR(ek)) {
765 ek->h.expiry_time = get_seconds()-1;
766 cache_put(&ek->h, &svc_expkey_cache);
768 svc_expkey_cache.nextcheck = get_seconds();
771 static int exp_fsid_hash(svc_client *clp, struct svc_export *exp)
773 u32 fsid[2];
775 if ((exp->ex_flags & NFSEXP_FSID) == 0)
776 return 0;
778 mk_fsid_v1(fsid, exp->ex_fsid);
779 return exp_set_key(clp, 1, fsid, exp);
782 static int exp_hash(struct auth_domain *clp, struct svc_export *exp)
784 u32 fsid[2];
785 struct inode *inode = exp->ex_dentry->d_inode;
786 dev_t dev = inode->i_sb->s_dev;
788 if (old_valid_dev(dev)) {
789 mk_fsid_v0(fsid, dev, inode->i_ino);
790 return exp_set_key(clp, 0, fsid, exp);
792 mk_fsid_v3(fsid, dev, inode->i_ino);
793 return exp_set_key(clp, 3, fsid, exp);
796 static void exp_unhash(struct svc_export *exp)
798 struct svc_expkey *ek;
799 struct inode *inode = exp->ex_dentry->d_inode;
801 ek = exp_get_key(exp->ex_client, inode->i_sb->s_dev, inode->i_ino);
802 if (ek && !IS_ERR(ek)) {
803 ek->h.expiry_time = get_seconds()-1;
804 cache_put(&ek->h, &svc_expkey_cache);
806 svc_expkey_cache.nextcheck = get_seconds();
810 * Export a file system.
813 exp_export(struct nfsctl_export *nxp)
815 svc_client *clp;
816 struct svc_export *exp = NULL;
817 struct svc_export new;
818 struct svc_expkey *fsid_key = NULL;
819 struct nameidata nd;
820 int err;
822 /* Consistency check */
823 err = -EINVAL;
824 if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) ||
825 !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX))
826 goto out;
828 dprintk("exp_export called for %s:%s (%x/%ld fl %x).\n",
829 nxp->ex_client, nxp->ex_path,
830 (unsigned)nxp->ex_dev, (long)nxp->ex_ino,
831 nxp->ex_flags);
833 /* Try to lock the export table for update */
834 exp_writelock();
836 /* Look up client info */
837 if (!(clp = auth_domain_find(nxp->ex_client)))
838 goto out_unlock;
841 /* Look up the dentry */
842 err = path_lookup(nxp->ex_path, 0, &nd);
843 if (err)
844 goto out_unlock;
845 err = -EINVAL;
847 exp = exp_get_by_name(clp, nd.mnt, nd.dentry, NULL);
849 /* must make sure there won't be an ex_fsid clash */
850 if ((nxp->ex_flags & NFSEXP_FSID) &&
851 (fsid_key = exp_get_fsid_key(clp, nxp->ex_dev)) &&
852 !IS_ERR(fsid_key) &&
853 fsid_key->ek_mnt &&
854 (fsid_key->ek_mnt != nd.mnt || fsid_key->ek_dentry != nd.dentry) )
855 goto finish;
857 if (exp) {
858 /* just a flags/id/fsid update */
860 exp_fsid_unhash(exp);
861 exp->ex_flags = nxp->ex_flags;
862 exp->ex_anon_uid = nxp->ex_anon_uid;
863 exp->ex_anon_gid = nxp->ex_anon_gid;
864 exp->ex_fsid = nxp->ex_dev;
866 err = exp_fsid_hash(clp, exp);
867 goto finish;
870 err = check_export(nd.dentry->d_inode, nxp->ex_flags);
871 if (err) goto finish;
873 err = -ENOMEM;
875 dprintk("nfsd: creating export entry %p for client %p\n", exp, clp);
877 new.h.expiry_time = NEVER;
878 new.h.flags = 0;
879 new.ex_client = clp;
880 new.ex_mnt = nd.mnt;
881 new.ex_dentry = nd.dentry;
882 new.ex_flags = nxp->ex_flags;
883 new.ex_anon_uid = nxp->ex_anon_uid;
884 new.ex_anon_gid = nxp->ex_anon_gid;
885 new.ex_fsid = nxp->ex_dev;
887 exp = svc_export_lookup(&new);
888 if (exp)
889 exp = svc_export_update(&new, exp);
891 if (!exp)
892 goto finish;
894 if (exp_hash(clp, exp) ||
895 exp_fsid_hash(clp, exp)) {
896 /* failed to create at least one index */
897 exp_do_unexport(exp);
898 cache_flush();
899 err = -ENOMEM;
902 finish:
903 if (exp)
904 exp_put(exp);
905 if (fsid_key && !IS_ERR(fsid_key))
906 cache_put(&fsid_key->h, &svc_expkey_cache);
907 if (clp)
908 auth_domain_put(clp);
909 path_release(&nd);
910 out_unlock:
911 exp_writeunlock();
912 out:
913 return err;
917 * Unexport a file system. The export entry has already
918 * been removed from the client's list of exported fs's.
920 static void
921 exp_do_unexport(svc_export *unexp)
923 unexp->h.expiry_time = get_seconds()-1;
924 svc_export_cache.nextcheck = get_seconds();
925 exp_unhash(unexp);
926 exp_fsid_unhash(unexp);
931 * unexport syscall.
934 exp_unexport(struct nfsctl_export *nxp)
936 struct auth_domain *dom;
937 svc_export *exp;
938 struct nameidata nd;
939 int err;
941 /* Consistency check */
942 if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) ||
943 !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX))
944 return -EINVAL;
946 exp_writelock();
948 err = -EINVAL;
949 dom = auth_domain_find(nxp->ex_client);
950 if (!dom) {
951 dprintk("nfsd: unexport couldn't find %s\n", nxp->ex_client);
952 goto out_unlock;
955 err = path_lookup(nxp->ex_path, 0, &nd);
956 if (err)
957 goto out_domain;
959 err = -EINVAL;
960 exp = exp_get_by_name(dom, nd.mnt, nd.dentry, NULL);
961 path_release(&nd);
962 if (!exp)
963 goto out_domain;
965 exp_do_unexport(exp);
966 exp_put(exp);
967 err = 0;
969 out_domain:
970 auth_domain_put(dom);
971 cache_flush();
972 out_unlock:
973 exp_writeunlock();
974 return err;
978 * Obtain the root fh on behalf of a client.
979 * This could be done in user space, but I feel that it adds some safety
980 * since its harder to fool a kernel module than a user space program.
983 exp_rootfh(svc_client *clp, char *path, struct knfsd_fh *f, int maxsize)
985 struct svc_export *exp;
986 struct nameidata nd;
987 struct inode *inode;
988 struct svc_fh fh;
989 int err;
991 err = -EPERM;
992 /* NB: we probably ought to check that it's NUL-terminated */
993 if (path_lookup(path, 0, &nd)) {
994 printk("nfsd: exp_rootfh path not found %s", path);
995 return err;
997 inode = nd.dentry->d_inode;
999 dprintk("nfsd: exp_rootfh(%s [%p] %s:%s/%ld)\n",
1000 path, nd.dentry, clp->name,
1001 inode->i_sb->s_id, inode->i_ino);
1002 exp = exp_parent(clp, nd.mnt, nd.dentry, NULL);
1003 if (!exp) {
1004 dprintk("nfsd: exp_rootfh export not found.\n");
1005 goto out;
1009 * fh must be initialized before calling fh_compose
1011 fh_init(&fh, maxsize);
1012 if (fh_compose(&fh, exp, nd.dentry, NULL))
1013 err = -EINVAL;
1014 else
1015 err = 0;
1016 memcpy(f, &fh.fh_handle, sizeof(struct knfsd_fh));
1017 fh_put(&fh);
1018 exp_put(exp);
1019 out:
1020 path_release(&nd);
1021 return err;
1024 struct svc_export *
1025 exp_find(struct auth_domain *clp, int fsid_type, u32 *fsidv,
1026 struct cache_req *reqp)
1028 struct svc_export *exp;
1029 struct svc_expkey *ek = exp_find_key(clp, fsid_type, fsidv, reqp);
1030 if (!ek || IS_ERR(ek))
1031 return ERR_PTR(PTR_ERR(ek));
1033 exp = exp_get_by_name(clp, ek->ek_mnt, ek->ek_dentry, reqp);
1034 cache_put(&ek->h, &svc_expkey_cache);
1036 if (!exp || IS_ERR(exp))
1037 return ERR_PTR(PTR_ERR(exp));
1038 return exp;
1043 * Called when we need the filehandle for the root of the pseudofs,
1044 * for a given NFSv4 client. The root is defined to be the
1045 * export point with fsid==0
1048 exp_pseudoroot(struct auth_domain *clp, struct svc_fh *fhp,
1049 struct cache_req *creq)
1051 struct svc_expkey *fsid_key;
1052 struct svc_export *exp;
1053 int rv;
1054 u32 fsidv[2];
1056 mk_fsid_v1(fsidv, 0);
1058 fsid_key = exp_find_key(clp, 1, fsidv, creq);
1059 if (IS_ERR(fsid_key) && PTR_ERR(fsid_key) == -EAGAIN)
1060 return nfserr_dropit;
1061 if (!fsid_key || IS_ERR(fsid_key))
1062 return nfserr_perm;
1064 exp = exp_get_by_name(clp, fsid_key->ek_mnt, fsid_key->ek_dentry, creq);
1065 if (exp == NULL)
1066 rv = nfserr_perm;
1067 else if (IS_ERR(exp))
1068 rv = nfserrno(PTR_ERR(exp));
1069 else
1070 rv = fh_compose(fhp, exp,
1071 fsid_key->ek_dentry, NULL);
1072 cache_put(&fsid_key->h, &svc_expkey_cache);
1073 return rv;
1076 /* Iterator */
1078 static void *e_start(struct seq_file *m, loff_t *pos)
1080 loff_t n = *pos;
1081 unsigned hash, export;
1082 struct cache_head *ch;
1084 exp_readlock();
1085 read_lock(&svc_export_cache.hash_lock);
1086 if (!n--)
1087 return (void *)1;
1088 hash = n >> 32;
1089 export = n & ((1LL<<32) - 1);
1092 for (ch=export_table[hash]; ch; ch=ch->next)
1093 if (!export--)
1094 return ch;
1095 n &= ~((1LL<<32) - 1);
1096 do {
1097 hash++;
1098 n += 1LL<<32;
1099 } while(hash < EXPORT_HASHMAX && export_table[hash]==NULL);
1100 if (hash >= EXPORT_HASHMAX)
1101 return NULL;
1102 *pos = n+1;
1103 return export_table[hash];
1106 static void *e_next(struct seq_file *m, void *p, loff_t *pos)
1108 struct cache_head *ch = p;
1109 int hash = (*pos >> 32);
1111 if (p == (void *)1)
1112 hash = 0;
1113 else if (ch->next == NULL) {
1114 hash++;
1115 *pos += 1LL<<32;
1116 } else {
1117 ++*pos;
1118 return ch->next;
1120 *pos &= ~((1LL<<32) - 1);
1121 while (hash < EXPORT_HASHMAX && export_table[hash] == NULL) {
1122 hash++;
1123 *pos += 1LL<<32;
1125 if (hash >= EXPORT_HASHMAX)
1126 return NULL;
1127 ++*pos;
1128 return export_table[hash];
1131 static void e_stop(struct seq_file *m, void *p)
1133 read_unlock(&svc_export_cache.hash_lock);
1134 exp_readunlock();
1137 static struct flags {
1138 int flag;
1139 char *name[2];
1140 } expflags[] = {
1141 { NFSEXP_READONLY, {"ro", "rw"}},
1142 { NFSEXP_INSECURE_PORT, {"insecure", ""}},
1143 { NFSEXP_ROOTSQUASH, {"root_squash", "no_root_squash"}},
1144 { NFSEXP_ALLSQUASH, {"all_squash", ""}},
1145 { NFSEXP_ASYNC, {"async", "sync"}},
1146 { NFSEXP_GATHERED_WRITES, {"wdelay", "no_wdelay"}},
1147 { NFSEXP_NOHIDE, {"nohide", ""}},
1148 { NFSEXP_CROSSMOUNT, {"crossmnt", ""}},
1149 { NFSEXP_NOSUBTREECHECK, {"no_subtree_check", ""}},
1150 { NFSEXP_NOAUTHNLM, {"insecure_locks", ""}},
1151 #ifdef MSNFS
1152 { NFSEXP_MSNFS, {"msnfs", ""}},
1153 #endif
1154 { 0, {"", ""}}
1157 static void exp_flags(struct seq_file *m, int flag, int fsid, uid_t anonu, uid_t anong)
1159 int first = 0;
1160 struct flags *flg;
1162 for (flg = expflags; flg->flag; flg++) {
1163 int state = (flg->flag & flag)?0:1;
1164 if (*flg->name[state])
1165 seq_printf(m, "%s%s", first++?",":"", flg->name[state]);
1167 if (flag & NFSEXP_FSID)
1168 seq_printf(m, "%sfsid=%d", first++?",":"", fsid);
1169 if (anonu != (uid_t)-2 && anonu != (0x10000-2))
1170 seq_printf(m, "%sanonuid=%d", first++?",":"", anonu);
1171 if (anong != (gid_t)-2 && anong != (0x10000-2))
1172 seq_printf(m, "%sanongid=%d", first++?",":"", anong);
1175 static int e_show(struct seq_file *m, void *p)
1177 struct cache_head *cp = p;
1178 struct svc_export *exp = container_of(cp, struct svc_export, h);
1179 svc_client *clp;
1181 if (p == (void *)1) {
1182 seq_puts(m, "# Version 1.1\n");
1183 seq_puts(m, "# Path Client(Flags) # IPs\n");
1184 return 0;
1187 clp = exp->ex_client;
1188 cache_get(&exp->h);
1189 if (cache_check(&svc_export_cache, &exp->h, NULL))
1190 return 0;
1191 cache_put(&exp->h, &svc_export_cache);
1192 return svc_export_show(m, &svc_export_cache, cp);
1195 struct seq_operations nfs_exports_op = {
1196 .start = e_start,
1197 .next = e_next,
1198 .stop = e_stop,
1199 .show = e_show,
1203 * Add or modify a client.
1204 * Change requests may involve the list of host addresses. The list of
1205 * exports and possibly existing uid maps are left untouched.
1208 exp_addclient(struct nfsctl_client *ncp)
1210 struct auth_domain *dom;
1211 int i, err;
1213 /* First, consistency check. */
1214 err = -EINVAL;
1215 if (! exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX))
1216 goto out;
1217 if (ncp->cl_naddr > NFSCLNT_ADDRMAX)
1218 goto out;
1220 /* Lock the hashtable */
1221 exp_writelock();
1223 dom = unix_domain_find(ncp->cl_ident);
1225 err = -ENOMEM;
1226 if (!dom)
1227 goto out_unlock;
1229 /* Insert client into hashtable. */
1230 for (i = 0; i < ncp->cl_naddr; i++)
1231 auth_unix_add_addr(ncp->cl_addrlist[i], dom);
1233 auth_unix_forget_old(dom);
1234 auth_domain_put(dom);
1236 err = 0;
1238 out_unlock:
1239 exp_writeunlock();
1240 out:
1241 return err;
1245 * Delete a client given an identifier.
1248 exp_delclient(struct nfsctl_client *ncp)
1250 int err;
1251 struct auth_domain *dom;
1253 err = -EINVAL;
1254 if (!exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX))
1255 goto out;
1257 /* Lock the hashtable */
1258 exp_writelock();
1260 dom = auth_domain_find(ncp->cl_ident);
1261 /* just make sure that no addresses work
1262 * and that it will expire soon
1264 if (dom) {
1265 err = auth_unix_forget_old(dom);
1266 auth_domain_put(dom);
1269 exp_writeunlock();
1270 out:
1271 return err;
1275 * Verify that string is non-empty and does not exceed max length.
1277 static int
1278 exp_verify_string(char *cp, int max)
1280 int i;
1282 for (i = 0; i < max; i++)
1283 if (!cp[i])
1284 return i;
1285 cp[i] = 0;
1286 printk(KERN_NOTICE "nfsd: couldn't validate string %s\n", cp);
1287 return 0;
1291 * Initialize the exports module.
1293 void
1294 nfsd_export_init(void)
1296 dprintk("nfsd: initializing export module.\n");
1298 cache_register(&svc_export_cache);
1299 cache_register(&svc_expkey_cache);
1304 * Flush exports table - called when last nfsd thread is killed
1306 void
1307 nfsd_export_flush(void)
1309 exp_writelock();
1310 cache_purge(&svc_expkey_cache);
1311 cache_purge(&svc_export_cache);
1312 exp_writeunlock();
1316 * Shutdown the exports module.
1318 void
1319 nfsd_export_shutdown(void)
1322 dprintk("nfsd: shutting down export module.\n");
1324 exp_writelock();
1326 if (cache_unregister(&svc_expkey_cache))
1327 printk(KERN_ERR "nfsd: failed to unregister expkey cache\n");
1328 if (cache_unregister(&svc_export_cache))
1329 printk(KERN_ERR "nfsd: failed to unregister export cache\n");
1330 svcauth_unix_purge();
1332 exp_writeunlock();
1333 dprintk("nfsd: export shutdown complete.\n");