NFS: Introduce nfs4_validate_mount_options
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / nfs / super.c
1 /*
2 * linux/fs/nfs/super.c
3 *
4 * Copyright (C) 1992 Rick Sladkey
5 *
6 * nfs superblock handling functions
7 *
8 * Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some
9 * experimental NFS changes. Modularisation taken straight from SYS5 fs.
10 *
11 * Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
12 * J.S.Peatfield@damtp.cam.ac.uk
13 *
14 * Split from inode.c by David Howells <dhowells@redhat.com>
15 *
16 * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
17 * particular server are held in the same superblock
18 * - NFS superblocks can have several effective roots to the dentry tree
19 * - directory type roots are spliced into the tree when a path from one root reaches the root
20 * of another (see nfs_lookup())
21 */
22
23 #include <linux/module.h>
24 #include <linux/init.h>
25
26 #include <linux/time.h>
27 #include <linux/kernel.h>
28 #include <linux/mm.h>
29 #include <linux/string.h>
30 #include <linux/stat.h>
31 #include <linux/errno.h>
32 #include <linux/unistd.h>
33 #include <linux/sunrpc/clnt.h>
34 #include <linux/sunrpc/stats.h>
35 #include <linux/sunrpc/metrics.h>
36 #include <linux/nfs_fs.h>
37 #include <linux/nfs_mount.h>
38 #include <linux/nfs4_mount.h>
39 #include <linux/lockd/bind.h>
40 #include <linux/smp_lock.h>
41 #include <linux/seq_file.h>
42 #include <linux/mount.h>
43 #include <linux/nfs_idmap.h>
44 #include <linux/vfs.h>
45 #include <linux/inet.h>
46 #include <linux/nfs_xdr.h>
47 #include <linux/magic.h>
48
49 #include <asm/system.h>
50 #include <asm/uaccess.h>
51
52 #include "nfs4_fs.h"
53 #include "callback.h"
54 #include "delegation.h"
55 #include "iostat.h"
56 #include "internal.h"
57
58 #define NFSDBG_FACILITY NFSDBG_VFS
59
60 static void nfs_umount_begin(struct vfsmount *, int);
61 static int nfs_statfs(struct dentry *, struct kstatfs *);
62 static int nfs_show_options(struct seq_file *, struct vfsmount *);
63 static int nfs_show_stats(struct seq_file *, struct vfsmount *);
64 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
65 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
66 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
67 static void nfs_kill_super(struct super_block *);
68
69 static struct file_system_type nfs_fs_type = {
70 .owner = THIS_MODULE,
71 .name = "nfs",
72 .get_sb = nfs_get_sb,
73 .kill_sb = nfs_kill_super,
74 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
75 };
76
77 struct file_system_type nfs_xdev_fs_type = {
78 .owner = THIS_MODULE,
79 .name = "nfs",
80 .get_sb = nfs_xdev_get_sb,
81 .kill_sb = nfs_kill_super,
82 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
83 };
84
85 static const struct super_operations nfs_sops = {
86 .alloc_inode = nfs_alloc_inode,
87 .destroy_inode = nfs_destroy_inode,
88 .write_inode = nfs_write_inode,
89 .statfs = nfs_statfs,
90 .clear_inode = nfs_clear_inode,
91 .umount_begin = nfs_umount_begin,
92 .show_options = nfs_show_options,
93 .show_stats = nfs_show_stats,
94 };
95
96 #ifdef CONFIG_NFS_V4
97 static int nfs4_get_sb(struct file_system_type *fs_type,
98 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
99 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
100 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
101 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
102 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
103 static void nfs4_kill_super(struct super_block *sb);
104
105 static struct file_system_type nfs4_fs_type = {
106 .owner = THIS_MODULE,
107 .name = "nfs4",
108 .get_sb = nfs4_get_sb,
109 .kill_sb = nfs4_kill_super,
110 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
111 };
112
113 struct file_system_type nfs4_xdev_fs_type = {
114 .owner = THIS_MODULE,
115 .name = "nfs4",
116 .get_sb = nfs4_xdev_get_sb,
117 .kill_sb = nfs4_kill_super,
118 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
119 };
120
121 struct file_system_type nfs4_referral_fs_type = {
122 .owner = THIS_MODULE,
123 .name = "nfs4",
124 .get_sb = nfs4_referral_get_sb,
125 .kill_sb = nfs4_kill_super,
126 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
127 };
128
129 static const struct super_operations nfs4_sops = {
130 .alloc_inode = nfs_alloc_inode,
131 .destroy_inode = nfs_destroy_inode,
132 .write_inode = nfs_write_inode,
133 .statfs = nfs_statfs,
134 .clear_inode = nfs4_clear_inode,
135 .umount_begin = nfs_umount_begin,
136 .show_options = nfs_show_options,
137 .show_stats = nfs_show_stats,
138 };
139 #endif
140
141 static struct shrinker *acl_shrinker;
142
143 /*
144 * Register the NFS filesystems
145 */
146 int __init register_nfs_fs(void)
147 {
148 int ret;
149
150 ret = register_filesystem(&nfs_fs_type);
151 if (ret < 0)
152 goto error_0;
153
154 ret = nfs_register_sysctl();
155 if (ret < 0)
156 goto error_1;
157 #ifdef CONFIG_NFS_V4
158 ret = register_filesystem(&nfs4_fs_type);
159 if (ret < 0)
160 goto error_2;
161 #endif
162 acl_shrinker = set_shrinker(DEFAULT_SEEKS, nfs_access_cache_shrinker);
163 return 0;
164
165 #ifdef CONFIG_NFS_V4
166 error_2:
167 nfs_unregister_sysctl();
168 #endif
169 error_1:
170 unregister_filesystem(&nfs_fs_type);
171 error_0:
172 return ret;
173 }
174
175 /*
176 * Unregister the NFS filesystems
177 */
178 void __exit unregister_nfs_fs(void)
179 {
180 if (acl_shrinker != NULL)
181 remove_shrinker(acl_shrinker);
182 #ifdef CONFIG_NFS_V4
183 unregister_filesystem(&nfs4_fs_type);
184 nfs_unregister_sysctl();
185 #endif
186 unregister_filesystem(&nfs_fs_type);
187 }
188
189 /*
190 * Deliver file system statistics to userspace
191 */
192 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
193 {
194 struct nfs_server *server = NFS_SB(dentry->d_sb);
195 unsigned char blockbits;
196 unsigned long blockres;
197 struct nfs_fh *fh = NFS_FH(dentry->d_inode);
198 struct nfs_fattr fattr;
199 struct nfs_fsstat res = {
200 .fattr = &fattr,
201 };
202 int error;
203
204 lock_kernel();
205
206 error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
207 if (error < 0)
208 goto out_err;
209 buf->f_type = NFS_SUPER_MAGIC;
210
211 /*
212 * Current versions of glibc do not correctly handle the
213 * case where f_frsize != f_bsize. Eventually we want to
214 * report the value of wtmult in this field.
215 */
216 buf->f_frsize = dentry->d_sb->s_blocksize;
217
218 /*
219 * On most *nix systems, f_blocks, f_bfree, and f_bavail
220 * are reported in units of f_frsize. Linux hasn't had
221 * an f_frsize field in its statfs struct until recently,
222 * thus historically Linux's sys_statfs reports these
223 * fields in units of f_bsize.
224 */
225 buf->f_bsize = dentry->d_sb->s_blocksize;
226 blockbits = dentry->d_sb->s_blocksize_bits;
227 blockres = (1 << blockbits) - 1;
228 buf->f_blocks = (res.tbytes + blockres) >> blockbits;
229 buf->f_bfree = (res.fbytes + blockres) >> blockbits;
230 buf->f_bavail = (res.abytes + blockres) >> blockbits;
231
232 buf->f_files = res.tfiles;
233 buf->f_ffree = res.afiles;
234
235 buf->f_namelen = server->namelen;
236
237 unlock_kernel();
238 return 0;
239
240 out_err:
241 dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
242 unlock_kernel();
243 return error;
244 }
245
246 /*
247 * Map the security flavour number to a name
248 */
249 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
250 {
251 static const struct {
252 rpc_authflavor_t flavour;
253 const char *str;
254 } sec_flavours[] = {
255 { RPC_AUTH_NULL, "null" },
256 { RPC_AUTH_UNIX, "sys" },
257 { RPC_AUTH_GSS_KRB5, "krb5" },
258 { RPC_AUTH_GSS_KRB5I, "krb5i" },
259 { RPC_AUTH_GSS_KRB5P, "krb5p" },
260 { RPC_AUTH_GSS_LKEY, "lkey" },
261 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
262 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
263 { RPC_AUTH_GSS_SPKM, "spkm" },
264 { RPC_AUTH_GSS_SPKMI, "spkmi" },
265 { RPC_AUTH_GSS_SPKMP, "spkmp" },
266 { UINT_MAX, "unknown" }
267 };
268 int i;
269
270 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
271 if (sec_flavours[i].flavour == flavour)
272 break;
273 }
274 return sec_flavours[i].str;
275 }
276
277 /*
278 * Describe the mount options in force on this server representation
279 */
280 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults)
281 {
282 static const struct proc_nfs_info {
283 int flag;
284 const char *str;
285 const char *nostr;
286 } nfs_info[] = {
287 { NFS_MOUNT_SOFT, ",soft", ",hard" },
288 { NFS_MOUNT_INTR, ",intr", "" },
289 { NFS_MOUNT_NOCTO, ",nocto", "" },
290 { NFS_MOUNT_NOAC, ",noac", "" },
291 { NFS_MOUNT_NONLM, ",nolock", "" },
292 { NFS_MOUNT_NOACL, ",noacl", "" },
293 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
294 { 0, NULL, NULL }
295 };
296 const struct proc_nfs_info *nfs_infop;
297 struct nfs_client *clp = nfss->nfs_client;
298 char buf[12];
299 const char *proto;
300
301 seq_printf(m, ",vers=%d", clp->rpc_ops->version);
302 seq_printf(m, ",rsize=%d", nfss->rsize);
303 seq_printf(m, ",wsize=%d", nfss->wsize);
304 if (nfss->acregmin != 3*HZ || showdefaults)
305 seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
306 if (nfss->acregmax != 60*HZ || showdefaults)
307 seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
308 if (nfss->acdirmin != 30*HZ || showdefaults)
309 seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
310 if (nfss->acdirmax != 60*HZ || showdefaults)
311 seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ);
312 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
313 if (nfss->flags & nfs_infop->flag)
314 seq_puts(m, nfs_infop->str);
315 else
316 seq_puts(m, nfs_infop->nostr);
317 }
318 switch (nfss->client->cl_xprt->prot) {
319 case IPPROTO_TCP:
320 proto = "tcp";
321 break;
322 case IPPROTO_UDP:
323 proto = "udp";
324 break;
325 default:
326 snprintf(buf, sizeof(buf), "%u", nfss->client->cl_xprt->prot);
327 proto = buf;
328 }
329 seq_printf(m, ",proto=%s", proto);
330 seq_printf(m, ",timeo=%lu", 10U * clp->retrans_timeo / HZ);
331 seq_printf(m, ",retrans=%u", clp->retrans_count);
332 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
333 }
334
335 /*
336 * Describe the mount options on this VFS mountpoint
337 */
338 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
339 {
340 struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
341
342 nfs_show_mount_options(m, nfss, 0);
343
344 seq_puts(m, ",addr=");
345 seq_escape(m, nfss->nfs_client->cl_hostname, " \t\n\\");
346
347 return 0;
348 }
349
350 /*
351 * Present statistical information for this VFS mountpoint
352 */
353 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
354 {
355 int i, cpu;
356 struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
357 struct rpc_auth *auth = nfss->client->cl_auth;
358 struct nfs_iostats totals = { };
359
360 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
361
362 /*
363 * Display all mount option settings
364 */
365 seq_printf(m, "\n\topts:\t");
366 seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
367 seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
368 seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
369 seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
370 nfs_show_mount_options(m, nfss, 1);
371
372 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
373
374 seq_printf(m, "\n\tcaps:\t");
375 seq_printf(m, "caps=0x%x", nfss->caps);
376 seq_printf(m, ",wtmult=%d", nfss->wtmult);
377 seq_printf(m, ",dtsize=%d", nfss->dtsize);
378 seq_printf(m, ",bsize=%d", nfss->bsize);
379 seq_printf(m, ",namelen=%d", nfss->namelen);
380
381 #ifdef CONFIG_NFS_V4
382 if (nfss->nfs_client->cl_nfsversion == 4) {
383 seq_printf(m, "\n\tnfsv4:\t");
384 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
385 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
386 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
387 }
388 #endif
389
390 /*
391 * Display security flavor in effect for this mount
392 */
393 seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor);
394 if (auth->au_flavor)
395 seq_printf(m, ",pseudoflavor=%d", auth->au_flavor);
396
397 /*
398 * Display superblock I/O counters
399 */
400 for_each_possible_cpu(cpu) {
401 struct nfs_iostats *stats;
402
403 preempt_disable();
404 stats = per_cpu_ptr(nfss->io_stats, cpu);
405
406 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
407 totals.events[i] += stats->events[i];
408 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
409 totals.bytes[i] += stats->bytes[i];
410
411 preempt_enable();
412 }
413
414 seq_printf(m, "\n\tevents:\t");
415 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
416 seq_printf(m, "%lu ", totals.events[i]);
417 seq_printf(m, "\n\tbytes:\t");
418 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
419 seq_printf(m, "%Lu ", totals.bytes[i]);
420 seq_printf(m, "\n");
421
422 rpc_print_iostats(m, nfss->client);
423
424 return 0;
425 }
426
427 /*
428 * Begin unmount by attempting to remove all automounted mountpoints we added
429 * in response to xdev traversals and referrals
430 */
431 static void nfs_umount_begin(struct vfsmount *vfsmnt, int flags)
432 {
433 struct nfs_server *server = NFS_SB(vfsmnt->mnt_sb);
434 struct rpc_clnt *rpc;
435
436 shrink_submounts(vfsmnt, &nfs_automount_list);
437
438 if (!(flags & MNT_FORCE))
439 return;
440 /* -EIO all pending I/O */
441 rpc = server->client_acl;
442 if (!IS_ERR(rpc))
443 rpc_killall_tasks(rpc);
444 rpc = server->client;
445 if (!IS_ERR(rpc))
446 rpc_killall_tasks(rpc);
447 }
448
449 /*
450 * Sanity-check a server address provided by the mount command
451 */
452 static int nfs_verify_server_address(struct sockaddr *addr)
453 {
454 switch (addr->sa_family) {
455 case AF_INET: {
456 struct sockaddr_in *sa = (struct sockaddr_in *) addr;
457 if (sa->sin_addr.s_addr != INADDR_ANY)
458 return 1;
459 break;
460 }
461 }
462
463 return 0;
464 }
465
466 /*
467 * Validate the NFS2/NFS3 mount data
468 * - fills in the mount root filehandle
469 */
470 static int nfs_validate_mount_data(struct nfs_mount_data *data,
471 struct nfs_fh *mntfh)
472 {
473 if (data == NULL)
474 goto out_no_data;
475
476 switch (data->version) {
477 case 1:
478 data->namlen = 0;
479 case 2:
480 data->bsize = 0;
481 case 3:
482 if (data->flags & NFS_MOUNT_VER3)
483 goto out_no_v3;
484 data->root.size = NFS2_FHSIZE;
485 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
486 case 4:
487 if (data->flags & NFS_MOUNT_SECFLAVOUR)
488 goto out_no_sec;
489 case 5:
490 memset(data->context, 0, sizeof(data->context));
491 case 6:
492 if (data->flags & NFS_MOUNT_VER3)
493 mntfh->size = data->root.size;
494 else
495 mntfh->size = NFS2_FHSIZE;
496
497 if (mntfh->size > sizeof(mntfh->data))
498 goto out_invalid_fh;
499
500 memcpy(mntfh->data, data->root.data, mntfh->size);
501 if (mntfh->size < sizeof(mntfh->data))
502 memset(mntfh->data + mntfh->size, 0,
503 sizeof(mntfh->data) - mntfh->size);
504 break;
505 default:
506 goto out_bad_version;
507 }
508
509 if (!(data->flags & NFS_MOUNT_SECFLAVOUR))
510 data->pseudoflavor = RPC_AUTH_UNIX;
511
512 #ifndef CONFIG_NFS_V3
513 if (data->flags & NFS_MOUNT_VER3)
514 goto out_v3_not_compiled;
515 #endif /* !CONFIG_NFS_V3 */
516
517 if (!nfs_verify_server_address((struct sockaddr *) &data->addr))
518 goto out_no_address;
519
520 return 0;
521
522 out_no_data:
523 dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
524 return -EINVAL;
525
526 out_no_v3:
527 dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
528 data->version);
529 return -EINVAL;
530
531 out_no_sec:
532 dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
533 return -EINVAL;
534
535 out_bad_version:
536 dfprintk(MOUNT, "NFS: bad nfs_mount_data version %d\n",
537 data->version);
538 return -EINVAL;
539
540 #ifndef CONFIG_NFS_V3
541 out_v3_not_compiled:
542 dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
543 return -EPROTONOSUPPORT;
544 #endif /* !CONFIG_NFS_V3 */
545
546 out_no_address:
547 dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
548 return -EINVAL;
549
550 out_invalid_fh:
551 dfprintk(MOUNT, "NFS: invalid root filehandle\n");
552 return -EINVAL;
553 }
554
555 /*
556 * Initialise the common bits of the superblock
557 */
558 static inline void nfs_initialise_sb(struct super_block *sb)
559 {
560 struct nfs_server *server = NFS_SB(sb);
561
562 sb->s_magic = NFS_SUPER_MAGIC;
563
564 /* We probably want something more informative here */
565 snprintf(sb->s_id, sizeof(sb->s_id),
566 "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
567
568 if (sb->s_blocksize == 0)
569 sb->s_blocksize = nfs_block_bits(server->wsize,
570 &sb->s_blocksize_bits);
571
572 if (server->flags & NFS_MOUNT_NOAC)
573 sb->s_flags |= MS_SYNCHRONOUS;
574
575 nfs_super_set_maxbytes(sb, server->maxfilesize);
576 }
577
578 /*
579 * Finish setting up an NFS2/3 superblock
580 */
581 static void nfs_fill_super(struct super_block *sb, struct nfs_mount_data *data)
582 {
583 struct nfs_server *server = NFS_SB(sb);
584
585 sb->s_blocksize_bits = 0;
586 sb->s_blocksize = 0;
587 if (data->bsize)
588 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
589
590 if (server->flags & NFS_MOUNT_VER3) {
591 /* The VFS shouldn't apply the umask to mode bits. We will do
592 * so ourselves when necessary.
593 */
594 sb->s_flags |= MS_POSIXACL;
595 sb->s_time_gran = 1;
596 }
597
598 sb->s_op = &nfs_sops;
599 nfs_initialise_sb(sb);
600 }
601
602 /*
603 * Finish setting up a cloned NFS2/3 superblock
604 */
605 static void nfs_clone_super(struct super_block *sb,
606 const struct super_block *old_sb)
607 {
608 struct nfs_server *server = NFS_SB(sb);
609
610 sb->s_blocksize_bits = old_sb->s_blocksize_bits;
611 sb->s_blocksize = old_sb->s_blocksize;
612 sb->s_maxbytes = old_sb->s_maxbytes;
613
614 if (server->flags & NFS_MOUNT_VER3) {
615 /* The VFS shouldn't apply the umask to mode bits. We will do
616 * so ourselves when necessary.
617 */
618 sb->s_flags |= MS_POSIXACL;
619 sb->s_time_gran = 1;
620 }
621
622 sb->s_op = old_sb->s_op;
623 nfs_initialise_sb(sb);
624 }
625
626 static int nfs_set_super(struct super_block *s, void *_server)
627 {
628 struct nfs_server *server = _server;
629 int ret;
630
631 s->s_fs_info = server;
632 ret = set_anon_super(s, server);
633 if (ret == 0)
634 server->s_dev = s->s_dev;
635 return ret;
636 }
637
638 static int nfs_compare_super(struct super_block *sb, void *data)
639 {
640 struct nfs_server *server = data, *old = NFS_SB(sb);
641
642 if (old->nfs_client != server->nfs_client)
643 return 0;
644 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
645 return 0;
646 return 1;
647 }
648
649 static int nfs_get_sb(struct file_system_type *fs_type,
650 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
651 {
652 struct nfs_server *server = NULL;
653 struct super_block *s;
654 struct nfs_fh mntfh;
655 struct nfs_mount_data *data = raw_data;
656 struct dentry *mntroot;
657 int error;
658
659 /* Validate the mount data */
660 error = nfs_validate_mount_data(data, &mntfh);
661 if (error < 0)
662 goto out;
663
664 /* Get a volume representation */
665 server = nfs_create_server(data, &mntfh);
666 if (IS_ERR(server)) {
667 error = PTR_ERR(server);
668 goto out;
669 }
670
671 /* Get a superblock - note that we may end up sharing one that already exists */
672 s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
673 if (IS_ERR(s)) {
674 error = PTR_ERR(s);
675 goto out_err_nosb;
676 }
677
678 if (s->s_fs_info != server) {
679 nfs_free_server(server);
680 server = NULL;
681 }
682
683 if (!s->s_root) {
684 /* initial superblock/root creation */
685 s->s_flags = flags;
686 nfs_fill_super(s, data);
687 }
688
689 mntroot = nfs_get_root(s, &mntfh);
690 if (IS_ERR(mntroot)) {
691 error = PTR_ERR(mntroot);
692 goto error_splat_super;
693 }
694
695 s->s_flags |= MS_ACTIVE;
696 mnt->mnt_sb = s;
697 mnt->mnt_root = mntroot;
698 error = 0;
699
700 out:
701 return error;
702
703 out_err_nosb:
704 nfs_free_server(server);
705 goto out;
706
707 error_splat_super:
708 up_write(&s->s_umount);
709 deactivate_super(s);
710 goto out;
711 }
712
713 /*
714 * Destroy an NFS2/3 superblock
715 */
716 static void nfs_kill_super(struct super_block *s)
717 {
718 struct nfs_server *server = NFS_SB(s);
719
720 kill_anon_super(s);
721 nfs_free_server(server);
722 }
723
724 /*
725 * Clone an NFS2/3 server record on xdev traversal (FSID-change)
726 */
727 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
728 const char *dev_name, void *raw_data,
729 struct vfsmount *mnt)
730 {
731 struct nfs_clone_mount *data = raw_data;
732 struct super_block *s;
733 struct nfs_server *server;
734 struct dentry *mntroot;
735 int error;
736
737 dprintk("--> nfs_xdev_get_sb()\n");
738
739 /* create a new volume representation */
740 server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
741 if (IS_ERR(server)) {
742 error = PTR_ERR(server);
743 goto out_err_noserver;
744 }
745
746 /* Get a superblock - note that we may end up sharing one that already exists */
747 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
748 if (IS_ERR(s)) {
749 error = PTR_ERR(s);
750 goto out_err_nosb;
751 }
752
753 if (s->s_fs_info != server) {
754 nfs_free_server(server);
755 server = NULL;
756 }
757
758 if (!s->s_root) {
759 /* initial superblock/root creation */
760 s->s_flags = flags;
761 nfs_clone_super(s, data->sb);
762 }
763
764 mntroot = nfs_get_root(s, data->fh);
765 if (IS_ERR(mntroot)) {
766 error = PTR_ERR(mntroot);
767 goto error_splat_super;
768 }
769
770 s->s_flags |= MS_ACTIVE;
771 mnt->mnt_sb = s;
772 mnt->mnt_root = mntroot;
773
774 dprintk("<-- nfs_xdev_get_sb() = 0\n");
775 return 0;
776
777 out_err_nosb:
778 nfs_free_server(server);
779 out_err_noserver:
780 dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
781 return error;
782
783 error_splat_super:
784 up_write(&s->s_umount);
785 deactivate_super(s);
786 dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
787 return error;
788 }
789
790 #ifdef CONFIG_NFS_V4
791
792 /*
793 * Finish setting up a cloned NFS4 superblock
794 */
795 static void nfs4_clone_super(struct super_block *sb,
796 const struct super_block *old_sb)
797 {
798 sb->s_blocksize_bits = old_sb->s_blocksize_bits;
799 sb->s_blocksize = old_sb->s_blocksize;
800 sb->s_maxbytes = old_sb->s_maxbytes;
801 sb->s_time_gran = 1;
802 sb->s_op = old_sb->s_op;
803 nfs_initialise_sb(sb);
804 }
805
806 /*
807 * Set up an NFS4 superblock
808 */
809 static void nfs4_fill_super(struct super_block *sb)
810 {
811 sb->s_time_gran = 1;
812 sb->s_op = &nfs4_sops;
813 nfs_initialise_sb(sb);
814 }
815
816 /*
817 * Validate NFSv4 mount options
818 */
819 static int nfs4_validate_mount_data(struct nfs4_mount_data **options,
820 const char *dev_name,
821 struct sockaddr_in *addr,
822 rpc_authflavor_t *authflavour,
823 char **hostname,
824 char **mntpath,
825 char **ip_addr)
826 {
827 struct nfs4_mount_data *data = *options;
828 char *c;
829
830 if (data == NULL)
831 goto out_no_data;
832
833 switch (data->version) {
834 case 1:
835 if (data->host_addrlen != sizeof(*addr))
836 goto out_no_address;
837 if (copy_from_user(addr, data->host_addr, sizeof(*addr)))
838 return -EFAULT;
839 if (addr->sin_port == 0)
840 addr->sin_port = htons(NFS_PORT);
841 if (!nfs_verify_server_address((struct sockaddr *) addr))
842 goto out_no_address;
843
844 switch (data->auth_flavourlen) {
845 case 0:
846 *authflavour = RPC_AUTH_UNIX;
847 break;
848 case 1:
849 if (copy_from_user(authflavour, data->auth_flavours,
850 sizeof(*authflavour)))
851 return -EFAULT;
852 break;
853 default:
854 goto out_inval_auth;
855 }
856
857 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
858 if (IS_ERR(c))
859 return PTR_ERR(c);
860 *hostname = c;
861
862 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
863 if (IS_ERR(c))
864 return PTR_ERR(c);
865 *mntpath = c;
866 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *mntpath);
867
868 c = strndup_user(data->client_addr.data, 16);
869 if (IS_ERR(c))
870 return PTR_ERR(c);
871 *ip_addr = c;
872
873 break;
874 default:
875 goto out_bad_version;
876 }
877
878 return 0;
879
880 out_no_data:
881 dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
882 return -EINVAL;
883
884 out_inval_auth:
885 dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
886 data->auth_flavourlen);
887 return -EINVAL;
888
889 out_no_address:
890 dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
891 return -EINVAL;
892
893 out_bad_version:
894 dfprintk(MOUNT, "NFS4: bad nfs_mount_data version %d\n",
895 data->version);
896 return -EINVAL;
897 }
898
899 /*
900 * Get the superblock for an NFS4 mountpoint
901 */
902 static int nfs4_get_sb(struct file_system_type *fs_type,
903 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
904 {
905 struct nfs4_mount_data *data = raw_data;
906 struct super_block *s;
907 struct nfs_server *server;
908 struct sockaddr_in addr;
909 rpc_authflavor_t authflavour;
910 struct nfs_fh mntfh;
911 struct dentry *mntroot;
912 char *mntpath = NULL, *hostname = NULL, *ip_addr = NULL;
913 int error;
914
915 /* Validate the mount data */
916 error = nfs4_validate_mount_data(&data, dev_name, &addr, &authflavour,
917 &hostname, &mntpath, &ip_addr);
918 if (error < 0)
919 goto out;
920
921 /* Get a volume representation */
922 server = nfs4_create_server(data, hostname, &addr, mntpath, ip_addr,
923 authflavour, &mntfh);
924 if (IS_ERR(server)) {
925 error = PTR_ERR(server);
926 goto out;
927 }
928
929 /* Get a superblock - note that we may end up sharing one that already exists */
930 s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
931 if (IS_ERR(s)) {
932 error = PTR_ERR(s);
933 goto out_free;
934 }
935
936 if (s->s_fs_info != server) {
937 nfs_free_server(server);
938 server = NULL;
939 }
940
941 if (!s->s_root) {
942 /* initial superblock/root creation */
943 s->s_flags = flags;
944 nfs4_fill_super(s);
945 }
946
947 mntroot = nfs4_get_root(s, &mntfh);
948 if (IS_ERR(mntroot)) {
949 error = PTR_ERR(mntroot);
950 goto error_splat_super;
951 }
952
953 s->s_flags |= MS_ACTIVE;
954 mnt->mnt_sb = s;
955 mnt->mnt_root = mntroot;
956 error = 0;
957
958 out:
959 kfree(ip_addr);
960 kfree(mntpath);
961 kfree(hostname);
962 return error;
963
964 out_free:
965 nfs_free_server(server);
966 goto out;
967
968 error_splat_super:
969 up_write(&s->s_umount);
970 deactivate_super(s);
971 goto out;
972 }
973
974 static void nfs4_kill_super(struct super_block *sb)
975 {
976 struct nfs_server *server = NFS_SB(sb);
977
978 nfs_return_all_delegations(sb);
979 kill_anon_super(sb);
980
981 nfs4_renewd_prepare_shutdown(server);
982 nfs_free_server(server);
983 }
984
985 /*
986 * Clone an NFS4 server record on xdev traversal (FSID-change)
987 */
988 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
989 const char *dev_name, void *raw_data,
990 struct vfsmount *mnt)
991 {
992 struct nfs_clone_mount *data = raw_data;
993 struct super_block *s;
994 struct nfs_server *server;
995 struct dentry *mntroot;
996 int error;
997
998 dprintk("--> nfs4_xdev_get_sb()\n");
999
1000 /* create a new volume representation */
1001 server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1002 if (IS_ERR(server)) {
1003 error = PTR_ERR(server);
1004 goto out_err_noserver;
1005 }
1006
1007 /* Get a superblock - note that we may end up sharing one that already exists */
1008 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
1009 if (IS_ERR(s)) {
1010 error = PTR_ERR(s);
1011 goto out_err_nosb;
1012 }
1013
1014 if (s->s_fs_info != server) {
1015 nfs_free_server(server);
1016 server = NULL;
1017 }
1018
1019 if (!s->s_root) {
1020 /* initial superblock/root creation */
1021 s->s_flags = flags;
1022 nfs4_clone_super(s, data->sb);
1023 }
1024
1025 mntroot = nfs4_get_root(s, data->fh);
1026 if (IS_ERR(mntroot)) {
1027 error = PTR_ERR(mntroot);
1028 goto error_splat_super;
1029 }
1030
1031 s->s_flags |= MS_ACTIVE;
1032 mnt->mnt_sb = s;
1033 mnt->mnt_root = mntroot;
1034
1035 dprintk("<-- nfs4_xdev_get_sb() = 0\n");
1036 return 0;
1037
1038 out_err_nosb:
1039 nfs_free_server(server);
1040 out_err_noserver:
1041 dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
1042 return error;
1043
1044 error_splat_super:
1045 up_write(&s->s_umount);
1046 deactivate_super(s);
1047 dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
1048 return error;
1049 }
1050
1051 /*
1052 * Create an NFS4 server record on referral traversal
1053 */
1054 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
1055 const char *dev_name, void *raw_data,
1056 struct vfsmount *mnt)
1057 {
1058 struct nfs_clone_mount *data = raw_data;
1059 struct super_block *s;
1060 struct nfs_server *server;
1061 struct dentry *mntroot;
1062 struct nfs_fh mntfh;
1063 int error;
1064
1065 dprintk("--> nfs4_referral_get_sb()\n");
1066
1067 /* create a new volume representation */
1068 server = nfs4_create_referral_server(data, &mntfh);
1069 if (IS_ERR(server)) {
1070 error = PTR_ERR(server);
1071 goto out_err_noserver;
1072 }
1073
1074 /* Get a superblock - note that we may end up sharing one that already exists */
1075 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
1076 if (IS_ERR(s)) {
1077 error = PTR_ERR(s);
1078 goto out_err_nosb;
1079 }
1080
1081 if (s->s_fs_info != server) {
1082 nfs_free_server(server);
1083 server = NULL;
1084 }
1085
1086 if (!s->s_root) {
1087 /* initial superblock/root creation */
1088 s->s_flags = flags;
1089 nfs4_fill_super(s);
1090 }
1091
1092 mntroot = nfs4_get_root(s, &mntfh);
1093 if (IS_ERR(mntroot)) {
1094 error = PTR_ERR(mntroot);
1095 goto error_splat_super;
1096 }
1097
1098 s->s_flags |= MS_ACTIVE;
1099 mnt->mnt_sb = s;
1100 mnt->mnt_root = mntroot;
1101
1102 dprintk("<-- nfs4_referral_get_sb() = 0\n");
1103 return 0;
1104
1105 out_err_nosb:
1106 nfs_free_server(server);
1107 out_err_noserver:
1108 dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
1109 return error;
1110
1111 error_splat_super:
1112 up_write(&s->s_umount);
1113 deactivate_super(s);
1114 dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
1115 return error;
1116 }
1117
1118 #endif /* CONFIG_NFS_V4 */