xref: /openbmc/linux/fs/nfs/super.c (revision b34081f1)
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@lxorguk.ukuu.org.uk>, 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/addr.h>
35 #include <linux/sunrpc/stats.h>
36 #include <linux/sunrpc/metrics.h>
37 #include <linux/sunrpc/xprtsock.h>
38 #include <linux/sunrpc/xprtrdma.h>
39 #include <linux/nfs_fs.h>
40 #include <linux/nfs_mount.h>
41 #include <linux/nfs4_mount.h>
42 #include <linux/lockd/bind.h>
43 #include <linux/seq_file.h>
44 #include <linux/mount.h>
45 #include <linux/namei.h>
46 #include <linux/nfs_idmap.h>
47 #include <linux/vfs.h>
48 #include <linux/inet.h>
49 #include <linux/in6.h>
50 #include <linux/slab.h>
51 #include <net/ipv6.h>
52 #include <linux/netdevice.h>
53 #include <linux/nfs_xdr.h>
54 #include <linux/magic.h>
55 #include <linux/parser.h>
56 #include <linux/nsproxy.h>
57 #include <linux/rcupdate.h>
58 
59 #include <asm/uaccess.h>
60 
61 #include "nfs4_fs.h"
62 #include "callback.h"
63 #include "delegation.h"
64 #include "iostat.h"
65 #include "internal.h"
66 #include "fscache.h"
67 #include "nfs4session.h"
68 #include "pnfs.h"
69 #include "nfs.h"
70 
71 #define NFSDBG_FACILITY		NFSDBG_VFS
72 #define NFS_TEXT_DATA		1
73 
74 #if IS_ENABLED(CONFIG_NFS_V3)
75 #define NFS_DEFAULT_VERSION 3
76 #else
77 #define NFS_DEFAULT_VERSION 2
78 #endif
79 
80 enum {
81 	/* Mount options that take no arguments */
82 	Opt_soft, Opt_hard,
83 	Opt_posix, Opt_noposix,
84 	Opt_cto, Opt_nocto,
85 	Opt_ac, Opt_noac,
86 	Opt_lock, Opt_nolock,
87 	Opt_udp, Opt_tcp, Opt_rdma,
88 	Opt_acl, Opt_noacl,
89 	Opt_rdirplus, Opt_nordirplus,
90 	Opt_sharecache, Opt_nosharecache,
91 	Opt_resvport, Opt_noresvport,
92 	Opt_fscache, Opt_nofscache,
93 	Opt_migration, Opt_nomigration,
94 
95 	/* Mount options that take integer arguments */
96 	Opt_port,
97 	Opt_rsize, Opt_wsize, Opt_bsize,
98 	Opt_timeo, Opt_retrans,
99 	Opt_acregmin, Opt_acregmax,
100 	Opt_acdirmin, Opt_acdirmax,
101 	Opt_actimeo,
102 	Opt_namelen,
103 	Opt_mountport,
104 	Opt_mountvers,
105 	Opt_minorversion,
106 
107 	/* Mount options that take string arguments */
108 	Opt_nfsvers,
109 	Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
110 	Opt_addr, Opt_mountaddr, Opt_clientaddr,
111 	Opt_lookupcache,
112 	Opt_fscache_uniq,
113 	Opt_local_lock,
114 
115 	/* Special mount options */
116 	Opt_userspace, Opt_deprecated, Opt_sloppy,
117 
118 	Opt_err
119 };
120 
121 static const match_table_t nfs_mount_option_tokens = {
122 	{ Opt_userspace, "bg" },
123 	{ Opt_userspace, "fg" },
124 	{ Opt_userspace, "retry=%s" },
125 
126 	{ Opt_sloppy, "sloppy" },
127 
128 	{ Opt_soft, "soft" },
129 	{ Opt_hard, "hard" },
130 	{ Opt_deprecated, "intr" },
131 	{ Opt_deprecated, "nointr" },
132 	{ Opt_posix, "posix" },
133 	{ Opt_noposix, "noposix" },
134 	{ Opt_cto, "cto" },
135 	{ Opt_nocto, "nocto" },
136 	{ Opt_ac, "ac" },
137 	{ Opt_noac, "noac" },
138 	{ Opt_lock, "lock" },
139 	{ Opt_nolock, "nolock" },
140 	{ Opt_udp, "udp" },
141 	{ Opt_tcp, "tcp" },
142 	{ Opt_rdma, "rdma" },
143 	{ Opt_acl, "acl" },
144 	{ Opt_noacl, "noacl" },
145 	{ Opt_rdirplus, "rdirplus" },
146 	{ Opt_nordirplus, "nordirplus" },
147 	{ Opt_sharecache, "sharecache" },
148 	{ Opt_nosharecache, "nosharecache" },
149 	{ Opt_resvport, "resvport" },
150 	{ Opt_noresvport, "noresvport" },
151 	{ Opt_fscache, "fsc" },
152 	{ Opt_nofscache, "nofsc" },
153 	{ Opt_migration, "migration" },
154 	{ Opt_nomigration, "nomigration" },
155 
156 	{ Opt_port, "port=%s" },
157 	{ Opt_rsize, "rsize=%s" },
158 	{ Opt_wsize, "wsize=%s" },
159 	{ Opt_bsize, "bsize=%s" },
160 	{ Opt_timeo, "timeo=%s" },
161 	{ Opt_retrans, "retrans=%s" },
162 	{ Opt_acregmin, "acregmin=%s" },
163 	{ Opt_acregmax, "acregmax=%s" },
164 	{ Opt_acdirmin, "acdirmin=%s" },
165 	{ Opt_acdirmax, "acdirmax=%s" },
166 	{ Opt_actimeo, "actimeo=%s" },
167 	{ Opt_namelen, "namlen=%s" },
168 	{ Opt_mountport, "mountport=%s" },
169 	{ Opt_mountvers, "mountvers=%s" },
170 	{ Opt_minorversion, "minorversion=%s" },
171 
172 	{ Opt_nfsvers, "nfsvers=%s" },
173 	{ Opt_nfsvers, "vers=%s" },
174 
175 	{ Opt_sec, "sec=%s" },
176 	{ Opt_proto, "proto=%s" },
177 	{ Opt_mountproto, "mountproto=%s" },
178 	{ Opt_addr, "addr=%s" },
179 	{ Opt_clientaddr, "clientaddr=%s" },
180 	{ Opt_mounthost, "mounthost=%s" },
181 	{ Opt_mountaddr, "mountaddr=%s" },
182 
183 	{ Opt_lookupcache, "lookupcache=%s" },
184 	{ Opt_fscache_uniq, "fsc=%s" },
185 	{ Opt_local_lock, "local_lock=%s" },
186 
187 	/* The following needs to be listed after all other options */
188 	{ Opt_nfsvers, "v%s" },
189 
190 	{ Opt_err, NULL }
191 };
192 
193 enum {
194 	Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
195 
196 	Opt_xprt_err
197 };
198 
199 static const match_table_t nfs_xprt_protocol_tokens = {
200 	{ Opt_xprt_udp, "udp" },
201 	{ Opt_xprt_udp6, "udp6" },
202 	{ Opt_xprt_tcp, "tcp" },
203 	{ Opt_xprt_tcp6, "tcp6" },
204 	{ Opt_xprt_rdma, "rdma" },
205 
206 	{ Opt_xprt_err, NULL }
207 };
208 
209 enum {
210 	Opt_sec_none, Opt_sec_sys,
211 	Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
212 	Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
213 	Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
214 
215 	Opt_sec_err
216 };
217 
218 static const match_table_t nfs_secflavor_tokens = {
219 	{ Opt_sec_none, "none" },
220 	{ Opt_sec_none, "null" },
221 	{ Opt_sec_sys, "sys" },
222 
223 	{ Opt_sec_krb5, "krb5" },
224 	{ Opt_sec_krb5i, "krb5i" },
225 	{ Opt_sec_krb5p, "krb5p" },
226 
227 	{ Opt_sec_lkey, "lkey" },
228 	{ Opt_sec_lkeyi, "lkeyi" },
229 	{ Opt_sec_lkeyp, "lkeyp" },
230 
231 	{ Opt_sec_spkm, "spkm3" },
232 	{ Opt_sec_spkmi, "spkm3i" },
233 	{ Opt_sec_spkmp, "spkm3p" },
234 
235 	{ Opt_sec_err, NULL }
236 };
237 
238 enum {
239 	Opt_lookupcache_all, Opt_lookupcache_positive,
240 	Opt_lookupcache_none,
241 
242 	Opt_lookupcache_err
243 };
244 
245 static match_table_t nfs_lookupcache_tokens = {
246 	{ Opt_lookupcache_all, "all" },
247 	{ Opt_lookupcache_positive, "pos" },
248 	{ Opt_lookupcache_positive, "positive" },
249 	{ Opt_lookupcache_none, "none" },
250 
251 	{ Opt_lookupcache_err, NULL }
252 };
253 
254 enum {
255 	Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
256 	Opt_local_lock_none,
257 
258 	Opt_local_lock_err
259 };
260 
261 static match_table_t nfs_local_lock_tokens = {
262 	{ Opt_local_lock_all, "all" },
263 	{ Opt_local_lock_flock, "flock" },
264 	{ Opt_local_lock_posix, "posix" },
265 	{ Opt_local_lock_none, "none" },
266 
267 	{ Opt_local_lock_err, NULL }
268 };
269 
270 enum {
271 	Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
272 	Opt_vers_4_1, Opt_vers_4_2,
273 
274 	Opt_vers_err
275 };
276 
277 static match_table_t nfs_vers_tokens = {
278 	{ Opt_vers_2, "2" },
279 	{ Opt_vers_3, "3" },
280 	{ Opt_vers_4, "4" },
281 	{ Opt_vers_4_0, "4.0" },
282 	{ Opt_vers_4_1, "4.1" },
283 	{ Opt_vers_4_2, "4.2" },
284 
285 	{ Opt_vers_err, NULL }
286 };
287 
288 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
289 		int flags, const char *dev_name, void *raw_data);
290 
291 struct file_system_type nfs_fs_type = {
292 	.owner		= THIS_MODULE,
293 	.name		= "nfs",
294 	.mount		= nfs_fs_mount,
295 	.kill_sb	= nfs_kill_super,
296 	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
297 };
298 MODULE_ALIAS_FS("nfs");
299 EXPORT_SYMBOL_GPL(nfs_fs_type);
300 
301 struct file_system_type nfs_xdev_fs_type = {
302 	.owner		= THIS_MODULE,
303 	.name		= "nfs",
304 	.mount		= nfs_xdev_mount,
305 	.kill_sb	= nfs_kill_super,
306 	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
307 };
308 
309 const struct super_operations nfs_sops = {
310 	.alloc_inode	= nfs_alloc_inode,
311 	.destroy_inode	= nfs_destroy_inode,
312 	.write_inode	= nfs_write_inode,
313 	.drop_inode	= nfs_drop_inode,
314 	.put_super	= nfs_put_super,
315 	.statfs		= nfs_statfs,
316 	.evict_inode	= nfs_evict_inode,
317 	.umount_begin	= nfs_umount_begin,
318 	.show_options	= nfs_show_options,
319 	.show_devname	= nfs_show_devname,
320 	.show_path	= nfs_show_path,
321 	.show_stats	= nfs_show_stats,
322 	.remount_fs	= nfs_remount,
323 };
324 EXPORT_SYMBOL_GPL(nfs_sops);
325 
326 #if IS_ENABLED(CONFIG_NFS_V4)
327 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
328 static int nfs4_validate_mount_data(void *options,
329 	struct nfs_parsed_mount_data *args, const char *dev_name);
330 
331 struct file_system_type nfs4_fs_type = {
332 	.owner		= THIS_MODULE,
333 	.name		= "nfs4",
334 	.mount		= nfs_fs_mount,
335 	.kill_sb	= nfs_kill_super,
336 	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
337 };
338 MODULE_ALIAS_FS("nfs4");
339 MODULE_ALIAS("nfs4");
340 EXPORT_SYMBOL_GPL(nfs4_fs_type);
341 
342 static int __init register_nfs4_fs(void)
343 {
344 	return register_filesystem(&nfs4_fs_type);
345 }
346 
347 static void unregister_nfs4_fs(void)
348 {
349 	unregister_filesystem(&nfs4_fs_type);
350 }
351 #else
352 static int __init register_nfs4_fs(void)
353 {
354 	return 0;
355 }
356 
357 static void unregister_nfs4_fs(void)
358 {
359 }
360 #endif
361 
362 static struct shrinker acl_shrinker = {
363 	.shrink		= nfs_access_cache_shrinker,
364 	.seeks		= DEFAULT_SEEKS,
365 };
366 
367 /*
368  * Register the NFS filesystems
369  */
370 int __init register_nfs_fs(void)
371 {
372 	int ret;
373 
374         ret = register_filesystem(&nfs_fs_type);
375 	if (ret < 0)
376 		goto error_0;
377 
378 	ret = register_nfs4_fs();
379 	if (ret < 0)
380 		goto error_1;
381 
382 	ret = nfs_register_sysctl();
383 	if (ret < 0)
384 		goto error_2;
385 	register_shrinker(&acl_shrinker);
386 	return 0;
387 
388 error_2:
389 	unregister_nfs4_fs();
390 error_1:
391 	unregister_filesystem(&nfs_fs_type);
392 error_0:
393 	return ret;
394 }
395 
396 /*
397  * Unregister the NFS filesystems
398  */
399 void __exit unregister_nfs_fs(void)
400 {
401 	unregister_shrinker(&acl_shrinker);
402 	nfs_unregister_sysctl();
403 	unregister_nfs4_fs();
404 	unregister_filesystem(&nfs_fs_type);
405 }
406 
407 void nfs_sb_active(struct super_block *sb)
408 {
409 	struct nfs_server *server = NFS_SB(sb);
410 
411 	if (atomic_inc_return(&server->active) == 1)
412 		atomic_inc(&sb->s_active);
413 }
414 EXPORT_SYMBOL_GPL(nfs_sb_active);
415 
416 void nfs_sb_deactive(struct super_block *sb)
417 {
418 	struct nfs_server *server = NFS_SB(sb);
419 
420 	if (atomic_dec_and_test(&server->active))
421 		deactivate_super(sb);
422 }
423 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
424 
425 /*
426  * Deliver file system statistics to userspace
427  */
428 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
429 {
430 	struct nfs_server *server = NFS_SB(dentry->d_sb);
431 	unsigned char blockbits;
432 	unsigned long blockres;
433 	struct nfs_fh *fh = NFS_FH(dentry->d_inode);
434 	struct nfs_fsstat res;
435 	int error = -ENOMEM;
436 
437 	res.fattr = nfs_alloc_fattr();
438 	if (res.fattr == NULL)
439 		goto out_err;
440 
441 	error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
442 	if (unlikely(error == -ESTALE)) {
443 		struct dentry *pd_dentry;
444 
445 		pd_dentry = dget_parent(dentry);
446 		if (pd_dentry != NULL) {
447 			nfs_zap_caches(pd_dentry->d_inode);
448 			dput(pd_dentry);
449 		}
450 	}
451 	nfs_free_fattr(res.fattr);
452 	if (error < 0)
453 		goto out_err;
454 
455 	buf->f_type = NFS_SUPER_MAGIC;
456 
457 	/*
458 	 * Current versions of glibc do not correctly handle the
459 	 * case where f_frsize != f_bsize.  Eventually we want to
460 	 * report the value of wtmult in this field.
461 	 */
462 	buf->f_frsize = dentry->d_sb->s_blocksize;
463 
464 	/*
465 	 * On most *nix systems, f_blocks, f_bfree, and f_bavail
466 	 * are reported in units of f_frsize.  Linux hasn't had
467 	 * an f_frsize field in its statfs struct until recently,
468 	 * thus historically Linux's sys_statfs reports these
469 	 * fields in units of f_bsize.
470 	 */
471 	buf->f_bsize = dentry->d_sb->s_blocksize;
472 	blockbits = dentry->d_sb->s_blocksize_bits;
473 	blockres = (1 << blockbits) - 1;
474 	buf->f_blocks = (res.tbytes + blockres) >> blockbits;
475 	buf->f_bfree = (res.fbytes + blockres) >> blockbits;
476 	buf->f_bavail = (res.abytes + blockres) >> blockbits;
477 
478 	buf->f_files = res.tfiles;
479 	buf->f_ffree = res.afiles;
480 
481 	buf->f_namelen = server->namelen;
482 
483 	return 0;
484 
485  out_err:
486 	dprintk("%s: statfs error = %d\n", __func__, -error);
487 	return error;
488 }
489 EXPORT_SYMBOL_GPL(nfs_statfs);
490 
491 /*
492  * Map the security flavour number to a name
493  */
494 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
495 {
496 	static const struct {
497 		rpc_authflavor_t flavour;
498 		const char *str;
499 	} sec_flavours[] = {
500 		{ RPC_AUTH_NULL, "null" },
501 		{ RPC_AUTH_UNIX, "sys" },
502 		{ RPC_AUTH_GSS_KRB5, "krb5" },
503 		{ RPC_AUTH_GSS_KRB5I, "krb5i" },
504 		{ RPC_AUTH_GSS_KRB5P, "krb5p" },
505 		{ RPC_AUTH_GSS_LKEY, "lkey" },
506 		{ RPC_AUTH_GSS_LKEYI, "lkeyi" },
507 		{ RPC_AUTH_GSS_LKEYP, "lkeyp" },
508 		{ RPC_AUTH_GSS_SPKM, "spkm" },
509 		{ RPC_AUTH_GSS_SPKMI, "spkmi" },
510 		{ RPC_AUTH_GSS_SPKMP, "spkmp" },
511 		{ UINT_MAX, "unknown" }
512 	};
513 	int i;
514 
515 	for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
516 		if (sec_flavours[i].flavour == flavour)
517 			break;
518 	}
519 	return sec_flavours[i].str;
520 }
521 
522 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
523 				  int showdefaults)
524 {
525 	struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
526 
527 	seq_printf(m, ",mountproto=");
528 	switch (sap->sa_family) {
529 	case AF_INET:
530 		switch (nfss->mountd_protocol) {
531 		case IPPROTO_UDP:
532 			seq_printf(m, RPCBIND_NETID_UDP);
533 			break;
534 		case IPPROTO_TCP:
535 			seq_printf(m, RPCBIND_NETID_TCP);
536 			break;
537 		default:
538 			if (showdefaults)
539 				seq_printf(m, "auto");
540 		}
541 		break;
542 	case AF_INET6:
543 		switch (nfss->mountd_protocol) {
544 		case IPPROTO_UDP:
545 			seq_printf(m, RPCBIND_NETID_UDP6);
546 			break;
547 		case IPPROTO_TCP:
548 			seq_printf(m, RPCBIND_NETID_TCP6);
549 			break;
550 		default:
551 			if (showdefaults)
552 				seq_printf(m, "auto");
553 		}
554 		break;
555 	default:
556 		if (showdefaults)
557 			seq_printf(m, "auto");
558 	}
559 }
560 
561 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
562 				    int showdefaults)
563 {
564 	struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
565 
566 	if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
567 		return;
568 
569 	switch (sap->sa_family) {
570 	case AF_INET: {
571 		struct sockaddr_in *sin = (struct sockaddr_in *)sap;
572 		seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
573 		break;
574 	}
575 	case AF_INET6: {
576 		struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
577 		seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
578 		break;
579 	}
580 	default:
581 		if (showdefaults)
582 			seq_printf(m, ",mountaddr=unspecified");
583 	}
584 
585 	if (nfss->mountd_version || showdefaults)
586 		seq_printf(m, ",mountvers=%u", nfss->mountd_version);
587 	if ((nfss->mountd_port &&
588 		nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
589 		showdefaults)
590 		seq_printf(m, ",mountport=%u", nfss->mountd_port);
591 
592 	nfs_show_mountd_netid(m, nfss, showdefaults);
593 }
594 
595 #if IS_ENABLED(CONFIG_NFS_V4)
596 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
597 				    int showdefaults)
598 {
599 	struct nfs_client *clp = nfss->nfs_client;
600 
601 	seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
602 }
603 #else
604 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
605 				    int showdefaults)
606 {
607 }
608 #endif
609 
610 static void nfs_show_nfs_version(struct seq_file *m,
611 		unsigned int version,
612 		unsigned int minorversion)
613 {
614 	seq_printf(m, ",vers=%u", version);
615 	if (version == 4)
616 		seq_printf(m, ".%u", minorversion);
617 }
618 
619 /*
620  * Describe the mount options in force on this server representation
621  */
622 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
623 				   int showdefaults)
624 {
625 	static const struct proc_nfs_info {
626 		int flag;
627 		const char *str;
628 		const char *nostr;
629 	} nfs_info[] = {
630 		{ NFS_MOUNT_SOFT, ",soft", ",hard" },
631 		{ NFS_MOUNT_POSIX, ",posix", "" },
632 		{ NFS_MOUNT_NOCTO, ",nocto", "" },
633 		{ NFS_MOUNT_NOAC, ",noac", "" },
634 		{ NFS_MOUNT_NONLM, ",nolock", "" },
635 		{ NFS_MOUNT_NOACL, ",noacl", "" },
636 		{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
637 		{ NFS_MOUNT_UNSHARED, ",nosharecache", "" },
638 		{ NFS_MOUNT_NORESVPORT, ",noresvport", "" },
639 		{ 0, NULL, NULL }
640 	};
641 	const struct proc_nfs_info *nfs_infop;
642 	struct nfs_client *clp = nfss->nfs_client;
643 	u32 version = clp->rpc_ops->version;
644 	int local_flock, local_fcntl;
645 
646 	nfs_show_nfs_version(m, version, clp->cl_minorversion);
647 	seq_printf(m, ",rsize=%u", nfss->rsize);
648 	seq_printf(m, ",wsize=%u", nfss->wsize);
649 	if (nfss->bsize != 0)
650 		seq_printf(m, ",bsize=%u", nfss->bsize);
651 	seq_printf(m, ",namlen=%u", nfss->namelen);
652 	if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
653 		seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
654 	if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
655 		seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
656 	if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
657 		seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
658 	if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
659 		seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
660 	for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
661 		if (nfss->flags & nfs_infop->flag)
662 			seq_puts(m, nfs_infop->str);
663 		else
664 			seq_puts(m, nfs_infop->nostr);
665 	}
666 	rcu_read_lock();
667 	seq_printf(m, ",proto=%s",
668 		   rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
669 	rcu_read_unlock();
670 	if (version == 4) {
671 		if (nfss->port != NFS_PORT)
672 			seq_printf(m, ",port=%u", nfss->port);
673 	} else
674 		if (nfss->port)
675 			seq_printf(m, ",port=%u", nfss->port);
676 
677 	seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
678 	seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
679 	seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
680 
681 	if (version != 4)
682 		nfs_show_mountd_options(m, nfss, showdefaults);
683 	else
684 		nfs_show_nfsv4_options(m, nfss, showdefaults);
685 
686 	if (nfss->options & NFS_OPTION_FSCACHE)
687 		seq_printf(m, ",fsc");
688 
689 	if (nfss->options & NFS_OPTION_MIGRATION)
690 		seq_printf(m, ",migration");
691 
692 	if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
693 		if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
694 			seq_printf(m, ",lookupcache=none");
695 		else
696 			seq_printf(m, ",lookupcache=pos");
697 	}
698 
699 	local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
700 	local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
701 
702 	if (!local_flock && !local_fcntl)
703 		seq_printf(m, ",local_lock=none");
704 	else if (local_flock && local_fcntl)
705 		seq_printf(m, ",local_lock=all");
706 	else if (local_flock)
707 		seq_printf(m, ",local_lock=flock");
708 	else
709 		seq_printf(m, ",local_lock=posix");
710 }
711 
712 /*
713  * Describe the mount options on this VFS mountpoint
714  */
715 int nfs_show_options(struct seq_file *m, struct dentry *root)
716 {
717 	struct nfs_server *nfss = NFS_SB(root->d_sb);
718 
719 	nfs_show_mount_options(m, nfss, 0);
720 
721 	rcu_read_lock();
722 	seq_printf(m, ",addr=%s",
723 			rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
724 							RPC_DISPLAY_ADDR));
725 	rcu_read_unlock();
726 
727 	return 0;
728 }
729 EXPORT_SYMBOL_GPL(nfs_show_options);
730 
731 #if IS_ENABLED(CONFIG_NFS_V4)
732 #ifdef CONFIG_NFS_V4_1
733 static void show_sessions(struct seq_file *m, struct nfs_server *server)
734 {
735 	if (nfs4_has_session(server->nfs_client))
736 		seq_printf(m, ",sessions");
737 }
738 #else
739 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
740 #endif
741 #endif
742 
743 #ifdef CONFIG_NFS_V4_1
744 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
745 {
746 	seq_printf(m, ",pnfs=");
747 	if (server->pnfs_curr_ld)
748 		seq_printf(m, "%s", server->pnfs_curr_ld->name);
749 	else
750 		seq_printf(m, "not configured");
751 }
752 
753 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
754 {
755 	if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
756 		struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
757 		seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
758 			   "date='%llu,%u'",
759 			   impl_id->name, impl_id->domain,
760 			   impl_id->date.seconds, impl_id->date.nseconds);
761 	}
762 }
763 #else
764 #if IS_ENABLED(CONFIG_NFS_V4)
765 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
766 {
767 }
768 #endif
769 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
770 {
771 }
772 #endif
773 
774 int nfs_show_devname(struct seq_file *m, struct dentry *root)
775 {
776 	char *page = (char *) __get_free_page(GFP_KERNEL);
777 	char *devname, *dummy;
778 	int err = 0;
779 	if (!page)
780 		return -ENOMEM;
781 	devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
782 	if (IS_ERR(devname))
783 		err = PTR_ERR(devname);
784 	else
785 		seq_escape(m, devname, " \t\n\\");
786 	free_page((unsigned long)page);
787 	return err;
788 }
789 EXPORT_SYMBOL_GPL(nfs_show_devname);
790 
791 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
792 {
793 	seq_puts(m, "/");
794 	return 0;
795 }
796 EXPORT_SYMBOL_GPL(nfs_show_path);
797 
798 /*
799  * Present statistical information for this VFS mountpoint
800  */
801 int nfs_show_stats(struct seq_file *m, struct dentry *root)
802 {
803 	int i, cpu;
804 	struct nfs_server *nfss = NFS_SB(root->d_sb);
805 	struct rpc_auth *auth = nfss->client->cl_auth;
806 	struct nfs_iostats totals = { };
807 
808 	seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
809 
810 	/*
811 	 * Display all mount option settings
812 	 */
813 	seq_printf(m, "\n\topts:\t");
814 	seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
815 	seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
816 	seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
817 	seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
818 	nfs_show_mount_options(m, nfss, 1);
819 
820 	seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
821 
822 	show_implementation_id(m, nfss);
823 
824 	seq_printf(m, "\n\tcaps:\t");
825 	seq_printf(m, "caps=0x%x", nfss->caps);
826 	seq_printf(m, ",wtmult=%u", nfss->wtmult);
827 	seq_printf(m, ",dtsize=%u", nfss->dtsize);
828 	seq_printf(m, ",bsize=%u", nfss->bsize);
829 	seq_printf(m, ",namlen=%u", nfss->namelen);
830 
831 #if IS_ENABLED(CONFIG_NFS_V4)
832 	if (nfss->nfs_client->rpc_ops->version == 4) {
833 		seq_printf(m, "\n\tnfsv4:\t");
834 		seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
835 		seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
836 		seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
837 		seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
838 		show_sessions(m, nfss);
839 		show_pnfs(m, nfss);
840 	}
841 #endif
842 
843 	/*
844 	 * Display security flavor in effect for this mount
845 	 */
846 	seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
847 	if (auth->au_flavor)
848 		seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
849 
850 	/*
851 	 * Display superblock I/O counters
852 	 */
853 	for_each_possible_cpu(cpu) {
854 		struct nfs_iostats *stats;
855 
856 		preempt_disable();
857 		stats = per_cpu_ptr(nfss->io_stats, cpu);
858 
859 		for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
860 			totals.events[i] += stats->events[i];
861 		for (i = 0; i < __NFSIOS_BYTESMAX; i++)
862 			totals.bytes[i] += stats->bytes[i];
863 #ifdef CONFIG_NFS_FSCACHE
864 		for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
865 			totals.fscache[i] += stats->fscache[i];
866 #endif
867 
868 		preempt_enable();
869 	}
870 
871 	seq_printf(m, "\n\tevents:\t");
872 	for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
873 		seq_printf(m, "%lu ", totals.events[i]);
874 	seq_printf(m, "\n\tbytes:\t");
875 	for (i = 0; i < __NFSIOS_BYTESMAX; i++)
876 		seq_printf(m, "%Lu ", totals.bytes[i]);
877 #ifdef CONFIG_NFS_FSCACHE
878 	if (nfss->options & NFS_OPTION_FSCACHE) {
879 		seq_printf(m, "\n\tfsc:\t");
880 		for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
881 			seq_printf(m, "%Lu ", totals.bytes[i]);
882 	}
883 #endif
884 	seq_printf(m, "\n");
885 
886 	rpc_print_iostats(m, nfss->client);
887 
888 	return 0;
889 }
890 EXPORT_SYMBOL_GPL(nfs_show_stats);
891 
892 /*
893  * Begin unmount by attempting to remove all automounted mountpoints we added
894  * in response to xdev traversals and referrals
895  */
896 void nfs_umount_begin(struct super_block *sb)
897 {
898 	struct nfs_server *server;
899 	struct rpc_clnt *rpc;
900 
901 	server = NFS_SB(sb);
902 	/* -EIO all pending I/O */
903 	rpc = server->client_acl;
904 	if (!IS_ERR(rpc))
905 		rpc_killall_tasks(rpc);
906 	rpc = server->client;
907 	if (!IS_ERR(rpc))
908 		rpc_killall_tasks(rpc);
909 }
910 EXPORT_SYMBOL_GPL(nfs_umount_begin);
911 
912 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
913 {
914 	struct nfs_parsed_mount_data *data;
915 
916 	data = kzalloc(sizeof(*data), GFP_KERNEL);
917 	if (data) {
918 		data->acregmin		= NFS_DEF_ACREGMIN;
919 		data->acregmax		= NFS_DEF_ACREGMAX;
920 		data->acdirmin		= NFS_DEF_ACDIRMIN;
921 		data->acdirmax		= NFS_DEF_ACDIRMAX;
922 		data->mount_server.port	= NFS_UNSPEC_PORT;
923 		data->nfs_server.port	= NFS_UNSPEC_PORT;
924 		data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
925 		data->auth_flavors[0]	= RPC_AUTH_MAXFLAVOR;
926 		data->auth_flavor_len	= 0;
927 		data->minorversion	= 0;
928 		data->need_mount	= true;
929 		data->net		= current->nsproxy->net_ns;
930 		security_init_mnt_opts(&data->lsm_opts);
931 	}
932 	return data;
933 }
934 
935 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
936 {
937 	if (data) {
938 		kfree(data->client_address);
939 		kfree(data->mount_server.hostname);
940 		kfree(data->nfs_server.export_path);
941 		kfree(data->nfs_server.hostname);
942 		kfree(data->fscache_uniq);
943 		security_free_mnt_opts(&data->lsm_opts);
944 		kfree(data);
945 	}
946 }
947 
948 /*
949  * Sanity-check a server address provided by the mount command.
950  *
951  * Address family must be initialized, and address must not be
952  * the ANY address for that family.
953  */
954 static int nfs_verify_server_address(struct sockaddr *addr)
955 {
956 	switch (addr->sa_family) {
957 	case AF_INET: {
958 		struct sockaddr_in *sa = (struct sockaddr_in *)addr;
959 		return sa->sin_addr.s_addr != htonl(INADDR_ANY);
960 	}
961 	case AF_INET6: {
962 		struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
963 		return !ipv6_addr_any(sa);
964 	}
965 	}
966 
967 	dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
968 	return 0;
969 }
970 
971 /*
972  * Select between a default port value and a user-specified port value.
973  * If a zero value is set, then autobind will be used.
974  */
975 static void nfs_set_port(struct sockaddr *sap, int *port,
976 				 const unsigned short default_port)
977 {
978 	if (*port == NFS_UNSPEC_PORT)
979 		*port = default_port;
980 
981 	rpc_set_port(sap, *port);
982 }
983 
984 /*
985  * Sanity check the NFS transport protocol.
986  *
987  */
988 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
989 {
990 	switch (mnt->nfs_server.protocol) {
991 	case XPRT_TRANSPORT_UDP:
992 	case XPRT_TRANSPORT_TCP:
993 	case XPRT_TRANSPORT_RDMA:
994 		break;
995 	default:
996 		mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
997 	}
998 }
999 
1000 /*
1001  * For text based NFSv2/v3 mounts, the mount protocol transport default
1002  * settings should depend upon the specified NFS transport.
1003  */
1004 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1005 {
1006 	nfs_validate_transport_protocol(mnt);
1007 
1008 	if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1009 	    mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1010 			return;
1011 	switch (mnt->nfs_server.protocol) {
1012 	case XPRT_TRANSPORT_UDP:
1013 		mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1014 		break;
1015 	case XPRT_TRANSPORT_TCP:
1016 	case XPRT_TRANSPORT_RDMA:
1017 		mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1018 	}
1019 }
1020 
1021 static void nfs_set_auth_parsed_mount_data(struct nfs_parsed_mount_data *data,
1022 		rpc_authflavor_t pseudoflavor)
1023 {
1024 	data->auth_flavors[0] = pseudoflavor;
1025 	data->auth_flavor_len = 1;
1026 }
1027 
1028 /*
1029  * Parse the value of the 'sec=' option.
1030  */
1031 static int nfs_parse_security_flavors(char *value,
1032 				      struct nfs_parsed_mount_data *mnt)
1033 {
1034 	substring_t args[MAX_OPT_ARGS];
1035 	rpc_authflavor_t pseudoflavor;
1036 
1037 	dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1038 
1039 	switch (match_token(value, nfs_secflavor_tokens, args)) {
1040 	case Opt_sec_none:
1041 		pseudoflavor = RPC_AUTH_NULL;
1042 		break;
1043 	case Opt_sec_sys:
1044 		pseudoflavor = RPC_AUTH_UNIX;
1045 		break;
1046 	case Opt_sec_krb5:
1047 		pseudoflavor = RPC_AUTH_GSS_KRB5;
1048 		break;
1049 	case Opt_sec_krb5i:
1050 		pseudoflavor = RPC_AUTH_GSS_KRB5I;
1051 		break;
1052 	case Opt_sec_krb5p:
1053 		pseudoflavor = RPC_AUTH_GSS_KRB5P;
1054 		break;
1055 	case Opt_sec_lkey:
1056 		pseudoflavor = RPC_AUTH_GSS_LKEY;
1057 		break;
1058 	case Opt_sec_lkeyi:
1059 		pseudoflavor = RPC_AUTH_GSS_LKEYI;
1060 		break;
1061 	case Opt_sec_lkeyp:
1062 		pseudoflavor = RPC_AUTH_GSS_LKEYP;
1063 		break;
1064 	case Opt_sec_spkm:
1065 		pseudoflavor = RPC_AUTH_GSS_SPKM;
1066 		break;
1067 	case Opt_sec_spkmi:
1068 		pseudoflavor = RPC_AUTH_GSS_SPKMI;
1069 		break;
1070 	case Opt_sec_spkmp:
1071 		pseudoflavor = RPC_AUTH_GSS_SPKMP;
1072 		break;
1073 	default:
1074 		return 0;
1075 	}
1076 
1077 	mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1078 	nfs_set_auth_parsed_mount_data(mnt, pseudoflavor);
1079 	return 1;
1080 }
1081 
1082 static int nfs_parse_version_string(char *string,
1083 		struct nfs_parsed_mount_data *mnt,
1084 		substring_t *args)
1085 {
1086 	mnt->flags &= ~NFS_MOUNT_VER3;
1087 	switch (match_token(string, nfs_vers_tokens, args)) {
1088 	case Opt_vers_2:
1089 		mnt->version = 2;
1090 		break;
1091 	case Opt_vers_3:
1092 		mnt->flags |= NFS_MOUNT_VER3;
1093 		mnt->version = 3;
1094 		break;
1095 	case Opt_vers_4:
1096 		/* Backward compatibility option. In future,
1097 		 * the mount program should always supply
1098 		 * a NFSv4 minor version number.
1099 		 */
1100 		mnt->version = 4;
1101 		break;
1102 	case Opt_vers_4_0:
1103 		mnt->version = 4;
1104 		mnt->minorversion = 0;
1105 		break;
1106 	case Opt_vers_4_1:
1107 		mnt->version = 4;
1108 		mnt->minorversion = 1;
1109 		break;
1110 	case Opt_vers_4_2:
1111 		mnt->version = 4;
1112 		mnt->minorversion = 2;
1113 		break;
1114 	default:
1115 		return 0;
1116 	}
1117 	return 1;
1118 }
1119 
1120 static int nfs_get_option_str(substring_t args[], char **option)
1121 {
1122 	kfree(*option);
1123 	*option = match_strdup(args);
1124 	return !*option;
1125 }
1126 
1127 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1128 {
1129 	int rc;
1130 	char *string;
1131 
1132 	string = match_strdup(args);
1133 	if (string == NULL)
1134 		return -ENOMEM;
1135 	rc = kstrtoul(string, 10, option);
1136 	kfree(string);
1137 
1138 	return rc;
1139 }
1140 
1141 /*
1142  * Error-check and convert a string of mount options from user space into
1143  * a data structure.  The whole mount string is processed; bad options are
1144  * skipped as they are encountered.  If there were no errors, return 1;
1145  * otherwise return 0 (zero).
1146  */
1147 static int nfs_parse_mount_options(char *raw,
1148 				   struct nfs_parsed_mount_data *mnt)
1149 {
1150 	char *p, *string, *secdata;
1151 	int rc, sloppy = 0, invalid_option = 0;
1152 	unsigned short protofamily = AF_UNSPEC;
1153 	unsigned short mountfamily = AF_UNSPEC;
1154 
1155 	if (!raw) {
1156 		dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1157 		return 1;
1158 	}
1159 	dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1160 
1161 	secdata = alloc_secdata();
1162 	if (!secdata)
1163 		goto out_nomem;
1164 
1165 	rc = security_sb_copy_data(raw, secdata);
1166 	if (rc)
1167 		goto out_security_failure;
1168 
1169 	rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1170 	if (rc)
1171 		goto out_security_failure;
1172 
1173 	free_secdata(secdata);
1174 
1175 	while ((p = strsep(&raw, ",")) != NULL) {
1176 		substring_t args[MAX_OPT_ARGS];
1177 		unsigned long option;
1178 		int token;
1179 
1180 		if (!*p)
1181 			continue;
1182 
1183 		dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1184 
1185 		token = match_token(p, nfs_mount_option_tokens, args);
1186 		switch (token) {
1187 
1188 		/*
1189 		 * boolean options:  foo/nofoo
1190 		 */
1191 		case Opt_soft:
1192 			mnt->flags |= NFS_MOUNT_SOFT;
1193 			break;
1194 		case Opt_hard:
1195 			mnt->flags &= ~NFS_MOUNT_SOFT;
1196 			break;
1197 		case Opt_posix:
1198 			mnt->flags |= NFS_MOUNT_POSIX;
1199 			break;
1200 		case Opt_noposix:
1201 			mnt->flags &= ~NFS_MOUNT_POSIX;
1202 			break;
1203 		case Opt_cto:
1204 			mnt->flags &= ~NFS_MOUNT_NOCTO;
1205 			break;
1206 		case Opt_nocto:
1207 			mnt->flags |= NFS_MOUNT_NOCTO;
1208 			break;
1209 		case Opt_ac:
1210 			mnt->flags &= ~NFS_MOUNT_NOAC;
1211 			break;
1212 		case Opt_noac:
1213 			mnt->flags |= NFS_MOUNT_NOAC;
1214 			break;
1215 		case Opt_lock:
1216 			mnt->flags &= ~NFS_MOUNT_NONLM;
1217 			mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1218 					NFS_MOUNT_LOCAL_FCNTL);
1219 			break;
1220 		case Opt_nolock:
1221 			mnt->flags |= NFS_MOUNT_NONLM;
1222 			mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1223 				       NFS_MOUNT_LOCAL_FCNTL);
1224 			break;
1225 		case Opt_udp:
1226 			mnt->flags &= ~NFS_MOUNT_TCP;
1227 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1228 			break;
1229 		case Opt_tcp:
1230 			mnt->flags |= NFS_MOUNT_TCP;
1231 			mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1232 			break;
1233 		case Opt_rdma:
1234 			mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1235 			mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1236 			xprt_load_transport(p);
1237 			break;
1238 		case Opt_acl:
1239 			mnt->flags &= ~NFS_MOUNT_NOACL;
1240 			break;
1241 		case Opt_noacl:
1242 			mnt->flags |= NFS_MOUNT_NOACL;
1243 			break;
1244 		case Opt_rdirplus:
1245 			mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1246 			break;
1247 		case Opt_nordirplus:
1248 			mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1249 			break;
1250 		case Opt_sharecache:
1251 			mnt->flags &= ~NFS_MOUNT_UNSHARED;
1252 			break;
1253 		case Opt_nosharecache:
1254 			mnt->flags |= NFS_MOUNT_UNSHARED;
1255 			break;
1256 		case Opt_resvport:
1257 			mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1258 			break;
1259 		case Opt_noresvport:
1260 			mnt->flags |= NFS_MOUNT_NORESVPORT;
1261 			break;
1262 		case Opt_fscache:
1263 			mnt->options |= NFS_OPTION_FSCACHE;
1264 			kfree(mnt->fscache_uniq);
1265 			mnt->fscache_uniq = NULL;
1266 			break;
1267 		case Opt_nofscache:
1268 			mnt->options &= ~NFS_OPTION_FSCACHE;
1269 			kfree(mnt->fscache_uniq);
1270 			mnt->fscache_uniq = NULL;
1271 			break;
1272 		case Opt_migration:
1273 			mnt->options |= NFS_OPTION_MIGRATION;
1274 			break;
1275 		case Opt_nomigration:
1276 			mnt->options &= NFS_OPTION_MIGRATION;
1277 			break;
1278 
1279 		/*
1280 		 * options that take numeric values
1281 		 */
1282 		case Opt_port:
1283 			if (nfs_get_option_ul(args, &option) ||
1284 			    option > USHRT_MAX)
1285 				goto out_invalid_value;
1286 			mnt->nfs_server.port = option;
1287 			break;
1288 		case Opt_rsize:
1289 			if (nfs_get_option_ul(args, &option))
1290 				goto out_invalid_value;
1291 			mnt->rsize = option;
1292 			break;
1293 		case Opt_wsize:
1294 			if (nfs_get_option_ul(args, &option))
1295 				goto out_invalid_value;
1296 			mnt->wsize = option;
1297 			break;
1298 		case Opt_bsize:
1299 			if (nfs_get_option_ul(args, &option))
1300 				goto out_invalid_value;
1301 			mnt->bsize = option;
1302 			break;
1303 		case Opt_timeo:
1304 			if (nfs_get_option_ul(args, &option) || option == 0)
1305 				goto out_invalid_value;
1306 			mnt->timeo = option;
1307 			break;
1308 		case Opt_retrans:
1309 			if (nfs_get_option_ul(args, &option) || option == 0)
1310 				goto out_invalid_value;
1311 			mnt->retrans = option;
1312 			break;
1313 		case Opt_acregmin:
1314 			if (nfs_get_option_ul(args, &option))
1315 				goto out_invalid_value;
1316 			mnt->acregmin = option;
1317 			break;
1318 		case Opt_acregmax:
1319 			if (nfs_get_option_ul(args, &option))
1320 				goto out_invalid_value;
1321 			mnt->acregmax = option;
1322 			break;
1323 		case Opt_acdirmin:
1324 			if (nfs_get_option_ul(args, &option))
1325 				goto out_invalid_value;
1326 			mnt->acdirmin = option;
1327 			break;
1328 		case Opt_acdirmax:
1329 			if (nfs_get_option_ul(args, &option))
1330 				goto out_invalid_value;
1331 			mnt->acdirmax = option;
1332 			break;
1333 		case Opt_actimeo:
1334 			if (nfs_get_option_ul(args, &option))
1335 				goto out_invalid_value;
1336 			mnt->acregmin = mnt->acregmax =
1337 			mnt->acdirmin = mnt->acdirmax = option;
1338 			break;
1339 		case Opt_namelen:
1340 			if (nfs_get_option_ul(args, &option))
1341 				goto out_invalid_value;
1342 			mnt->namlen = option;
1343 			break;
1344 		case Opt_mountport:
1345 			if (nfs_get_option_ul(args, &option) ||
1346 			    option > USHRT_MAX)
1347 				goto out_invalid_value;
1348 			mnt->mount_server.port = option;
1349 			break;
1350 		case Opt_mountvers:
1351 			if (nfs_get_option_ul(args, &option) ||
1352 			    option < NFS_MNT_VERSION ||
1353 			    option > NFS_MNT3_VERSION)
1354 				goto out_invalid_value;
1355 			mnt->mount_server.version = option;
1356 			break;
1357 		case Opt_minorversion:
1358 			if (nfs_get_option_ul(args, &option))
1359 				goto out_invalid_value;
1360 			if (option > NFS4_MAX_MINOR_VERSION)
1361 				goto out_invalid_value;
1362 			mnt->minorversion = option;
1363 			break;
1364 
1365 		/*
1366 		 * options that take text values
1367 		 */
1368 		case Opt_nfsvers:
1369 			string = match_strdup(args);
1370 			if (string == NULL)
1371 				goto out_nomem;
1372 			rc = nfs_parse_version_string(string, mnt, args);
1373 			kfree(string);
1374 			if (!rc)
1375 				goto out_invalid_value;
1376 			break;
1377 		case Opt_sec:
1378 			string = match_strdup(args);
1379 			if (string == NULL)
1380 				goto out_nomem;
1381 			rc = nfs_parse_security_flavors(string, mnt);
1382 			kfree(string);
1383 			if (!rc) {
1384 				dfprintk(MOUNT, "NFS:   unrecognized "
1385 						"security flavor\n");
1386 				return 0;
1387 			}
1388 			break;
1389 		case Opt_proto:
1390 			string = match_strdup(args);
1391 			if (string == NULL)
1392 				goto out_nomem;
1393 			token = match_token(string,
1394 					    nfs_xprt_protocol_tokens, args);
1395 
1396 			protofamily = AF_INET;
1397 			switch (token) {
1398 			case Opt_xprt_udp6:
1399 				protofamily = AF_INET6;
1400 			case Opt_xprt_udp:
1401 				mnt->flags &= ~NFS_MOUNT_TCP;
1402 				mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1403 				break;
1404 			case Opt_xprt_tcp6:
1405 				protofamily = AF_INET6;
1406 			case Opt_xprt_tcp:
1407 				mnt->flags |= NFS_MOUNT_TCP;
1408 				mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1409 				break;
1410 			case Opt_xprt_rdma:
1411 				/* vector side protocols to TCP */
1412 				mnt->flags |= NFS_MOUNT_TCP;
1413 				mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1414 				xprt_load_transport(string);
1415 				break;
1416 			default:
1417 				dfprintk(MOUNT, "NFS:   unrecognized "
1418 						"transport protocol\n");
1419 				kfree(string);
1420 				return 0;
1421 			}
1422 			kfree(string);
1423 			break;
1424 		case Opt_mountproto:
1425 			string = match_strdup(args);
1426 			if (string == NULL)
1427 				goto out_nomem;
1428 			token = match_token(string,
1429 					    nfs_xprt_protocol_tokens, args);
1430 			kfree(string);
1431 
1432 			mountfamily = AF_INET;
1433 			switch (token) {
1434 			case Opt_xprt_udp6:
1435 				mountfamily = AF_INET6;
1436 			case Opt_xprt_udp:
1437 				mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1438 				break;
1439 			case Opt_xprt_tcp6:
1440 				mountfamily = AF_INET6;
1441 			case Opt_xprt_tcp:
1442 				mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1443 				break;
1444 			case Opt_xprt_rdma: /* not used for side protocols */
1445 			default:
1446 				dfprintk(MOUNT, "NFS:   unrecognized "
1447 						"transport protocol\n");
1448 				return 0;
1449 			}
1450 			break;
1451 		case Opt_addr:
1452 			string = match_strdup(args);
1453 			if (string == NULL)
1454 				goto out_nomem;
1455 			mnt->nfs_server.addrlen =
1456 				rpc_pton(mnt->net, string, strlen(string),
1457 					(struct sockaddr *)
1458 					&mnt->nfs_server.address,
1459 					sizeof(mnt->nfs_server.address));
1460 			kfree(string);
1461 			if (mnt->nfs_server.addrlen == 0)
1462 				goto out_invalid_address;
1463 			break;
1464 		case Opt_clientaddr:
1465 			if (nfs_get_option_str(args, &mnt->client_address))
1466 				goto out_nomem;
1467 			break;
1468 		case Opt_mounthost:
1469 			if (nfs_get_option_str(args,
1470 					       &mnt->mount_server.hostname))
1471 				goto out_nomem;
1472 			break;
1473 		case Opt_mountaddr:
1474 			string = match_strdup(args);
1475 			if (string == NULL)
1476 				goto out_nomem;
1477 			mnt->mount_server.addrlen =
1478 				rpc_pton(mnt->net, string, strlen(string),
1479 					(struct sockaddr *)
1480 					&mnt->mount_server.address,
1481 					sizeof(mnt->mount_server.address));
1482 			kfree(string);
1483 			if (mnt->mount_server.addrlen == 0)
1484 				goto out_invalid_address;
1485 			break;
1486 		case Opt_lookupcache:
1487 			string = match_strdup(args);
1488 			if (string == NULL)
1489 				goto out_nomem;
1490 			token = match_token(string,
1491 					nfs_lookupcache_tokens, args);
1492 			kfree(string);
1493 			switch (token) {
1494 				case Opt_lookupcache_all:
1495 					mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1496 					break;
1497 				case Opt_lookupcache_positive:
1498 					mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1499 					mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1500 					break;
1501 				case Opt_lookupcache_none:
1502 					mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1503 					break;
1504 				default:
1505 					dfprintk(MOUNT, "NFS:   invalid "
1506 							"lookupcache argument\n");
1507 					return 0;
1508 			};
1509 			break;
1510 		case Opt_fscache_uniq:
1511 			if (nfs_get_option_str(args, &mnt->fscache_uniq))
1512 				goto out_nomem;
1513 			mnt->options |= NFS_OPTION_FSCACHE;
1514 			break;
1515 		case Opt_local_lock:
1516 			string = match_strdup(args);
1517 			if (string == NULL)
1518 				goto out_nomem;
1519 			token = match_token(string, nfs_local_lock_tokens,
1520 					args);
1521 			kfree(string);
1522 			switch (token) {
1523 			case Opt_local_lock_all:
1524 				mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1525 					       NFS_MOUNT_LOCAL_FCNTL);
1526 				break;
1527 			case Opt_local_lock_flock:
1528 				mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1529 				break;
1530 			case Opt_local_lock_posix:
1531 				mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1532 				break;
1533 			case Opt_local_lock_none:
1534 				mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1535 						NFS_MOUNT_LOCAL_FCNTL);
1536 				break;
1537 			default:
1538 				dfprintk(MOUNT, "NFS:	invalid	"
1539 						"local_lock argument\n");
1540 				return 0;
1541 			};
1542 			break;
1543 
1544 		/*
1545 		 * Special options
1546 		 */
1547 		case Opt_sloppy:
1548 			sloppy = 1;
1549 			dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1550 			break;
1551 		case Opt_userspace:
1552 		case Opt_deprecated:
1553 			dfprintk(MOUNT, "NFS:   ignoring mount option "
1554 					"'%s'\n", p);
1555 			break;
1556 
1557 		default:
1558 			invalid_option = 1;
1559 			dfprintk(MOUNT, "NFS:   unrecognized mount option "
1560 					"'%s'\n", p);
1561 		}
1562 	}
1563 
1564 	if (!sloppy && invalid_option)
1565 		return 0;
1566 
1567 	if (mnt->minorversion && mnt->version != 4)
1568 		goto out_minorversion_mismatch;
1569 
1570 	if (mnt->options & NFS_OPTION_MIGRATION &&
1571 	    mnt->version != 4 && mnt->minorversion != 0)
1572 		goto out_migration_misuse;
1573 
1574 	/*
1575 	 * verify that any proto=/mountproto= options match the address
1576 	 * families in the addr=/mountaddr= options.
1577 	 */
1578 	if (protofamily != AF_UNSPEC &&
1579 	    protofamily != mnt->nfs_server.address.ss_family)
1580 		goto out_proto_mismatch;
1581 
1582 	if (mountfamily != AF_UNSPEC) {
1583 		if (mnt->mount_server.addrlen) {
1584 			if (mountfamily != mnt->mount_server.address.ss_family)
1585 				goto out_mountproto_mismatch;
1586 		} else {
1587 			if (mountfamily != mnt->nfs_server.address.ss_family)
1588 				goto out_mountproto_mismatch;
1589 		}
1590 	}
1591 
1592 	return 1;
1593 
1594 out_mountproto_mismatch:
1595 	printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1596 			 "option\n");
1597 	return 0;
1598 out_proto_mismatch:
1599 	printk(KERN_INFO "NFS: server address does not match proto= option\n");
1600 	return 0;
1601 out_invalid_address:
1602 	printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1603 	return 0;
1604 out_invalid_value:
1605 	printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1606 	return 0;
1607 out_minorversion_mismatch:
1608 	printk(KERN_INFO "NFS: mount option vers=%u does not support "
1609 			 "minorversion=%u\n", mnt->version, mnt->minorversion);
1610 	return 0;
1611 out_migration_misuse:
1612 	printk(KERN_INFO
1613 		"NFS: 'migration' not supported for this NFS version\n");
1614 	return 0;
1615 out_nomem:
1616 	printk(KERN_INFO "NFS: not enough memory to parse option\n");
1617 	return 0;
1618 out_security_failure:
1619 	free_secdata(secdata);
1620 	printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1621 	return 0;
1622 }
1623 
1624 /*
1625  * Ensure that the specified authtype in args->auth_flavors[0] is supported by
1626  * the server. Returns 0 if it's ok, and -EACCES if not.
1627  */
1628 static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
1629 			rpc_authflavor_t *server_authlist, unsigned int count)
1630 {
1631 	unsigned int i;
1632 
1633 	/*
1634 	 * If the sec= mount option is used, the specified flavor or AUTH_NULL
1635 	 * must be in the list returned by the server.
1636 	 *
1637 	 * AUTH_NULL has a special meaning when it's in the server list - it
1638 	 * means that the server will ignore the rpc creds, so any flavor
1639 	 * can be used.
1640 	 */
1641 	for (i = 0; i < count; i++) {
1642 		if (args->auth_flavors[0] == server_authlist[i] ||
1643 		    server_authlist[i] == RPC_AUTH_NULL)
1644 			goto out;
1645 	}
1646 
1647 	dfprintk(MOUNT, "NFS: auth flavor %u not supported by server\n",
1648 		args->auth_flavors[0]);
1649 	return -EACCES;
1650 
1651 out:
1652 	dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
1653 	return 0;
1654 }
1655 
1656 /*
1657  * Use the remote server's MOUNT service to request the NFS file handle
1658  * corresponding to the provided path.
1659  */
1660 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1661 			     struct nfs_fh *root_fh,
1662 			     rpc_authflavor_t *server_authlist,
1663 			     unsigned int *server_authlist_len)
1664 {
1665 	struct nfs_mount_request request = {
1666 		.sap		= (struct sockaddr *)
1667 						&args->mount_server.address,
1668 		.dirpath	= args->nfs_server.export_path,
1669 		.protocol	= args->mount_server.protocol,
1670 		.fh		= root_fh,
1671 		.noresvport	= args->flags & NFS_MOUNT_NORESVPORT,
1672 		.auth_flav_len	= server_authlist_len,
1673 		.auth_flavs	= server_authlist,
1674 		.net		= args->net,
1675 	};
1676 	int status;
1677 
1678 	if (args->mount_server.version == 0) {
1679 		switch (args->version) {
1680 			default:
1681 				args->mount_server.version = NFS_MNT3_VERSION;
1682 				break;
1683 			case 2:
1684 				args->mount_server.version = NFS_MNT_VERSION;
1685 		}
1686 	}
1687 	request.version = args->mount_server.version;
1688 
1689 	if (args->mount_server.hostname)
1690 		request.hostname = args->mount_server.hostname;
1691 	else
1692 		request.hostname = args->nfs_server.hostname;
1693 
1694 	/*
1695 	 * Construct the mount server's address.
1696 	 */
1697 	if (args->mount_server.address.ss_family == AF_UNSPEC) {
1698 		memcpy(request.sap, &args->nfs_server.address,
1699 		       args->nfs_server.addrlen);
1700 		args->mount_server.addrlen = args->nfs_server.addrlen;
1701 	}
1702 	request.salen = args->mount_server.addrlen;
1703 	nfs_set_port(request.sap, &args->mount_server.port, 0);
1704 
1705 	/*
1706 	 * Now ask the mount server to map our export path
1707 	 * to a file handle.
1708 	 */
1709 	status = nfs_mount(&request);
1710 	if (status != 0) {
1711 		dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1712 				request.hostname, status);
1713 		return status;
1714 	}
1715 
1716 	return 0;
1717 }
1718 
1719 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1720 					struct nfs_subversion *nfs_mod)
1721 {
1722 	int status;
1723 	unsigned int i;
1724 	bool tried_auth_unix = false;
1725 	bool auth_null_in_list = false;
1726 	struct nfs_server *server = ERR_PTR(-EACCES);
1727 	struct nfs_parsed_mount_data *args = mount_info->parsed;
1728 	rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1729 	unsigned int authlist_len = ARRAY_SIZE(authlist);
1730 
1731 	status = nfs_request_mount(args, mount_info->mntfh, authlist,
1732 					&authlist_len);
1733 	if (status)
1734 		return ERR_PTR(status);
1735 
1736 	/*
1737 	 * Was a sec= authflavor specified in the options? First, verify
1738 	 * whether the server supports it, and then just try to use it if so.
1739 	 */
1740 	if (args->auth_flavor_len > 0) {
1741 		status = nfs_verify_authflavor(args, authlist, authlist_len);
1742 		dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
1743 		if (status)
1744 			return ERR_PTR(status);
1745 		return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1746 	}
1747 
1748 	/*
1749 	 * No sec= option was provided. RFC 2623, section 2.7 suggests we
1750 	 * SHOULD prefer the flavor listed first. However, some servers list
1751 	 * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1752 	 */
1753 	for (i = 0; i < authlist_len; ++i) {
1754 		rpc_authflavor_t flavor;
1755 		struct rpcsec_gss_info info;
1756 
1757 		flavor = authlist[i];
1758 		switch (flavor) {
1759 		case RPC_AUTH_UNIX:
1760 			tried_auth_unix = true;
1761 			break;
1762 		case RPC_AUTH_NULL:
1763 			auth_null_in_list = true;
1764 			continue;
1765 		default:
1766 			if (rpcauth_get_gssinfo(flavor, &info) != 0)
1767 				continue;
1768 			/* Fallthrough */
1769 		}
1770 		dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1771 		nfs_set_auth_parsed_mount_data(args, flavor);
1772 		server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1773 		if (!IS_ERR(server))
1774 			return server;
1775 	}
1776 
1777 	/*
1778 	 * Nothing we tried so far worked. At this point, give up if we've
1779 	 * already tried AUTH_UNIX or if the server's list doesn't contain
1780 	 * AUTH_NULL
1781 	 */
1782 	if (tried_auth_unix || !auth_null_in_list)
1783 		return server;
1784 
1785 	/* Last chance! Try AUTH_UNIX */
1786 	dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1787 	nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
1788 	return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1789 }
1790 
1791 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1792 			     struct nfs_mount_info *mount_info,
1793 			     struct nfs_subversion *nfs_mod)
1794 {
1795 	struct nfs_server *server;
1796 
1797 	if (mount_info->parsed->need_mount)
1798 		server = nfs_try_mount_request(mount_info, nfs_mod);
1799 	else
1800 		server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1801 
1802 	if (IS_ERR(server))
1803 		return ERR_CAST(server);
1804 
1805 	return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1806 }
1807 EXPORT_SYMBOL_GPL(nfs_try_mount);
1808 
1809 /*
1810  * Split "dev_name" into "hostname:export_path".
1811  *
1812  * The leftmost colon demarks the split between the server's hostname
1813  * and the export path.  If the hostname starts with a left square
1814  * bracket, then it may contain colons.
1815  *
1816  * Note: caller frees hostname and export path, even on error.
1817  */
1818 static int nfs_parse_devname(const char *dev_name,
1819 			     char **hostname, size_t maxnamlen,
1820 			     char **export_path, size_t maxpathlen)
1821 {
1822 	size_t len;
1823 	char *end;
1824 
1825 	/* Is the host name protected with square brakcets? */
1826 	if (*dev_name == '[') {
1827 		end = strchr(++dev_name, ']');
1828 		if (end == NULL || end[1] != ':')
1829 			goto out_bad_devname;
1830 
1831 		len = end - dev_name;
1832 		end++;
1833 	} else {
1834 		char *comma;
1835 
1836 		end = strchr(dev_name, ':');
1837 		if (end == NULL)
1838 			goto out_bad_devname;
1839 		len = end - dev_name;
1840 
1841 		/* kill possible hostname list: not supported */
1842 		comma = strchr(dev_name, ',');
1843 		if (comma != NULL && comma < end)
1844 			*comma = 0;
1845 	}
1846 
1847 	if (len > maxnamlen)
1848 		goto out_hostname;
1849 
1850 	/* N.B. caller will free nfs_server.hostname in all cases */
1851 	*hostname = kstrndup(dev_name, len, GFP_KERNEL);
1852 	if (*hostname == NULL)
1853 		goto out_nomem;
1854 	len = strlen(++end);
1855 	if (len > maxpathlen)
1856 		goto out_path;
1857 	*export_path = kstrndup(end, len, GFP_KERNEL);
1858 	if (!*export_path)
1859 		goto out_nomem;
1860 
1861 	dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1862 	return 0;
1863 
1864 out_bad_devname:
1865 	dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1866 	return -EINVAL;
1867 
1868 out_nomem:
1869 	dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1870 	return -ENOMEM;
1871 
1872 out_hostname:
1873 	dfprintk(MOUNT, "NFS: server hostname too long\n");
1874 	return -ENAMETOOLONG;
1875 
1876 out_path:
1877 	dfprintk(MOUNT, "NFS: export pathname too long\n");
1878 	return -ENAMETOOLONG;
1879 }
1880 
1881 /*
1882  * Validate the NFS2/NFS3 mount data
1883  * - fills in the mount root filehandle
1884  *
1885  * For option strings, user space handles the following behaviors:
1886  *
1887  * + DNS: mapping server host name to IP address ("addr=" option)
1888  *
1889  * + failure mode: how to behave if a mount request can't be handled
1890  *   immediately ("fg/bg" option)
1891  *
1892  * + retry: how often to retry a mount request ("retry=" option)
1893  *
1894  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1895  *   mountproto=tcp after mountproto=udp, and so on
1896  */
1897 static int nfs23_validate_mount_data(void *options,
1898 				     struct nfs_parsed_mount_data *args,
1899 				     struct nfs_fh *mntfh,
1900 				     const char *dev_name)
1901 {
1902 	struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1903 	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1904 	int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1905 
1906 	if (data == NULL)
1907 		goto out_no_data;
1908 
1909 	args->version = NFS_DEFAULT_VERSION;
1910 	switch (data->version) {
1911 	case 1:
1912 		data->namlen = 0;
1913 	case 2:
1914 		data->bsize = 0;
1915 	case 3:
1916 		if (data->flags & NFS_MOUNT_VER3)
1917 			goto out_no_v3;
1918 		data->root.size = NFS2_FHSIZE;
1919 		memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1920 		/* Turn off security negotiation */
1921 		extra_flags |= NFS_MOUNT_SECFLAVOUR;
1922 	case 4:
1923 		if (data->flags & NFS_MOUNT_SECFLAVOUR)
1924 			goto out_no_sec;
1925 	case 5:
1926 		memset(data->context, 0, sizeof(data->context));
1927 	case 6:
1928 		if (data->flags & NFS_MOUNT_VER3) {
1929 			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1930 				goto out_invalid_fh;
1931 			mntfh->size = data->root.size;
1932 			args->version = 3;
1933 		} else {
1934 			mntfh->size = NFS2_FHSIZE;
1935 			args->version = 2;
1936 		}
1937 
1938 
1939 		memcpy(mntfh->data, data->root.data, mntfh->size);
1940 		if (mntfh->size < sizeof(mntfh->data))
1941 			memset(mntfh->data + mntfh->size, 0,
1942 			       sizeof(mntfh->data) - mntfh->size);
1943 
1944 		/*
1945 		 * Translate to nfs_parsed_mount_data, which nfs_fill_super
1946 		 * can deal with.
1947 		 */
1948 		args->flags		= data->flags & NFS_MOUNT_FLAGMASK;
1949 		args->flags		|= extra_flags;
1950 		args->rsize		= data->rsize;
1951 		args->wsize		= data->wsize;
1952 		args->timeo		= data->timeo;
1953 		args->retrans		= data->retrans;
1954 		args->acregmin		= data->acregmin;
1955 		args->acregmax		= data->acregmax;
1956 		args->acdirmin		= data->acdirmin;
1957 		args->acdirmax		= data->acdirmax;
1958 		args->need_mount	= false;
1959 
1960 		memcpy(sap, &data->addr, sizeof(data->addr));
1961 		args->nfs_server.addrlen = sizeof(data->addr);
1962 		args->nfs_server.port = ntohs(data->addr.sin_port);
1963 		if (!nfs_verify_server_address(sap))
1964 			goto out_no_address;
1965 
1966 		if (!(data->flags & NFS_MOUNT_TCP))
1967 			args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1968 		/* N.B. caller will free nfs_server.hostname in all cases */
1969 		args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1970 		args->namlen		= data->namlen;
1971 		args->bsize		= data->bsize;
1972 
1973 		if (data->flags & NFS_MOUNT_SECFLAVOUR)
1974 			nfs_set_auth_parsed_mount_data(args, data->pseudoflavor);
1975 		else
1976 			nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
1977 		if (!args->nfs_server.hostname)
1978 			goto out_nomem;
1979 
1980 		if (!(data->flags & NFS_MOUNT_NONLM))
1981 			args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1982 					 NFS_MOUNT_LOCAL_FCNTL);
1983 		else
1984 			args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1985 					NFS_MOUNT_LOCAL_FCNTL);
1986 		/*
1987 		 * The legacy version 6 binary mount data from userspace has a
1988 		 * field used only to transport selinux information into the
1989 		 * the kernel.  To continue to support that functionality we
1990 		 * have a touch of selinux knowledge here in the NFS code. The
1991 		 * userspace code converted context=blah to just blah so we are
1992 		 * converting back to the full string selinux understands.
1993 		 */
1994 		if (data->context[0]){
1995 #ifdef CONFIG_SECURITY_SELINUX
1996 			int rc;
1997 			char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1998 			if (!opts_str)
1999 				return -ENOMEM;
2000 			strcpy(opts_str, "context=");
2001 			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2002 			strcat(opts_str, &data->context[0]);
2003 			rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2004 			kfree(opts_str);
2005 			if (rc)
2006 				return rc;
2007 #else
2008 			return -EINVAL;
2009 #endif
2010 		}
2011 
2012 		break;
2013 	default:
2014 		return NFS_TEXT_DATA;
2015 	}
2016 
2017 #if !IS_ENABLED(CONFIG_NFS_V3)
2018 	if (args->version == 3)
2019 		goto out_v3_not_compiled;
2020 #endif /* !CONFIG_NFS_V3 */
2021 
2022 	return 0;
2023 
2024 out_no_data:
2025 	dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2026 	return -EINVAL;
2027 
2028 out_no_v3:
2029 	dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2030 		 data->version);
2031 	return -EINVAL;
2032 
2033 out_no_sec:
2034 	dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2035 	return -EINVAL;
2036 
2037 #if !IS_ENABLED(CONFIG_NFS_V3)
2038 out_v3_not_compiled:
2039 	dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
2040 	return -EPROTONOSUPPORT;
2041 #endif /* !CONFIG_NFS_V3 */
2042 
2043 out_nomem:
2044 	dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2045 	return -ENOMEM;
2046 
2047 out_no_address:
2048 	dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2049 	return -EINVAL;
2050 
2051 out_invalid_fh:
2052 	dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2053 	return -EINVAL;
2054 }
2055 
2056 #if IS_ENABLED(CONFIG_NFS_V4)
2057 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2058 				   void *options,
2059 				   struct nfs_parsed_mount_data *args,
2060 				   struct nfs_fh *mntfh,
2061 				   const char *dev_name)
2062 {
2063 	if (fs_type == &nfs_fs_type)
2064 		return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2065 	return nfs4_validate_mount_data(options, args, dev_name);
2066 }
2067 #else
2068 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2069 				   void *options,
2070 				   struct nfs_parsed_mount_data *args,
2071 				   struct nfs_fh *mntfh,
2072 				   const char *dev_name)
2073 {
2074 	return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2075 }
2076 #endif
2077 
2078 static int nfs_validate_text_mount_data(void *options,
2079 					struct nfs_parsed_mount_data *args,
2080 					const char *dev_name)
2081 {
2082 	int port = 0;
2083 	int max_namelen = PAGE_SIZE;
2084 	int max_pathlen = NFS_MAXPATHLEN;
2085 	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2086 
2087 	if (nfs_parse_mount_options((char *)options, args) == 0)
2088 		return -EINVAL;
2089 
2090 	if (!nfs_verify_server_address(sap))
2091 		goto out_no_address;
2092 
2093 	if (args->version == 4) {
2094 #if IS_ENABLED(CONFIG_NFS_V4)
2095 		port = NFS_PORT;
2096 		max_namelen = NFS4_MAXNAMLEN;
2097 		max_pathlen = NFS4_MAXPATHLEN;
2098 		nfs_validate_transport_protocol(args);
2099 		if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2100 			goto out_invalid_transport_udp;
2101 		nfs4_validate_mount_flags(args);
2102 #else
2103 		goto out_v4_not_compiled;
2104 #endif /* CONFIG_NFS_V4 */
2105 	} else
2106 		nfs_set_mount_transport_protocol(args);
2107 
2108 	nfs_set_port(sap, &args->nfs_server.port, port);
2109 
2110 	if (args->auth_flavor_len > 1)
2111 		goto out_bad_auth;
2112 
2113 	return nfs_parse_devname(dev_name,
2114 				   &args->nfs_server.hostname,
2115 				   max_namelen,
2116 				   &args->nfs_server.export_path,
2117 				   max_pathlen);
2118 
2119 #if !IS_ENABLED(CONFIG_NFS_V4)
2120 out_v4_not_compiled:
2121 	dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2122 	return -EPROTONOSUPPORT;
2123 #else
2124 out_invalid_transport_udp:
2125 	dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2126 	return -EINVAL;
2127 #endif /* !CONFIG_NFS_V4 */
2128 
2129 out_no_address:
2130 	dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2131 	return -EINVAL;
2132 
2133 out_bad_auth:
2134 	dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2135 	return -EINVAL;
2136 }
2137 
2138 static int
2139 nfs_compare_remount_data(struct nfs_server *nfss,
2140 			 struct nfs_parsed_mount_data *data)
2141 {
2142 	if (data->flags != nfss->flags ||
2143 	    data->rsize != nfss->rsize ||
2144 	    data->wsize != nfss->wsize ||
2145 	    data->retrans != nfss->client->cl_timeout->to_retries ||
2146 	    data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2147 	    data->acregmin != nfss->acregmin / HZ ||
2148 	    data->acregmax != nfss->acregmax / HZ ||
2149 	    data->acdirmin != nfss->acdirmin / HZ ||
2150 	    data->acdirmax != nfss->acdirmax / HZ ||
2151 	    data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2152 	    data->nfs_server.port != nfss->port ||
2153 	    data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2154 	    !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2155 			  (struct sockaddr *)&nfss->nfs_client->cl_addr))
2156 		return -EINVAL;
2157 
2158 	return 0;
2159 }
2160 
2161 int
2162 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2163 {
2164 	int error;
2165 	struct nfs_server *nfss = sb->s_fs_info;
2166 	struct nfs_parsed_mount_data *data;
2167 	struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2168 	struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2169 	u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2170 
2171 	/*
2172 	 * Userspace mount programs that send binary options generally send
2173 	 * them populated with default values. We have no way to know which
2174 	 * ones were explicitly specified. Fall back to legacy behavior and
2175 	 * just return success.
2176 	 */
2177 	if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2178 	    (nfsvers <= 3 && (!options || (options->version >= 1 &&
2179 					   options->version <= 6))))
2180 		return 0;
2181 
2182 	data = kzalloc(sizeof(*data), GFP_KERNEL);
2183 	if (data == NULL)
2184 		return -ENOMEM;
2185 
2186 	/* fill out struct with values from existing mount */
2187 	data->flags = nfss->flags;
2188 	data->rsize = nfss->rsize;
2189 	data->wsize = nfss->wsize;
2190 	data->retrans = nfss->client->cl_timeout->to_retries;
2191 	nfs_set_auth_parsed_mount_data(data, nfss->client->cl_auth->au_flavor);
2192 	data->acregmin = nfss->acregmin / HZ;
2193 	data->acregmax = nfss->acregmax / HZ;
2194 	data->acdirmin = nfss->acdirmin / HZ;
2195 	data->acdirmax = nfss->acdirmax / HZ;
2196 	data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2197 	data->nfs_server.port = nfss->port;
2198 	data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2199 	memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2200 		data->nfs_server.addrlen);
2201 
2202 	/* overwrite those values with any that were specified */
2203 	error = nfs_parse_mount_options((char *)options, data);
2204 	if (error < 0)
2205 		goto out;
2206 
2207 	/*
2208 	 * noac is a special case. It implies -o sync, but that's not
2209 	 * necessarily reflected in the mtab options. do_remount_sb
2210 	 * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2211 	 * remount options, so we have to explicitly reset it.
2212 	 */
2213 	if (data->flags & NFS_MOUNT_NOAC)
2214 		*flags |= MS_SYNCHRONOUS;
2215 
2216 	/* compare new mount options with old ones */
2217 	error = nfs_compare_remount_data(nfss, data);
2218 out:
2219 	kfree(data);
2220 	return error;
2221 }
2222 EXPORT_SYMBOL_GPL(nfs_remount);
2223 
2224 /*
2225  * Initialise the common bits of the superblock
2226  */
2227 inline void nfs_initialise_sb(struct super_block *sb)
2228 {
2229 	struct nfs_server *server = NFS_SB(sb);
2230 
2231 	sb->s_magic = NFS_SUPER_MAGIC;
2232 
2233 	/* We probably want something more informative here */
2234 	snprintf(sb->s_id, sizeof(sb->s_id),
2235 		 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2236 
2237 	if (sb->s_blocksize == 0)
2238 		sb->s_blocksize = nfs_block_bits(server->wsize,
2239 						 &sb->s_blocksize_bits);
2240 
2241 	sb->s_bdi = &server->backing_dev_info;
2242 
2243 	nfs_super_set_maxbytes(sb, server->maxfilesize);
2244 }
2245 
2246 /*
2247  * Finish setting up an NFS2/3 superblock
2248  */
2249 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2250 {
2251 	struct nfs_parsed_mount_data *data = mount_info->parsed;
2252 	struct nfs_server *server = NFS_SB(sb);
2253 
2254 	sb->s_blocksize_bits = 0;
2255 	sb->s_blocksize = 0;
2256 	sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2257 	sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2258 	if (data && data->bsize)
2259 		sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2260 
2261 	if (server->nfs_client->rpc_ops->version != 2) {
2262 		/* The VFS shouldn't apply the umask to mode bits. We will do
2263 		 * so ourselves when necessary.
2264 		 */
2265 		sb->s_flags |= MS_POSIXACL;
2266 		sb->s_time_gran = 1;
2267 	}
2268 
2269  	nfs_initialise_sb(sb);
2270 }
2271 EXPORT_SYMBOL_GPL(nfs_fill_super);
2272 
2273 /*
2274  * Finish setting up a cloned NFS2/3/4 superblock
2275  */
2276 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2277 {
2278 	const struct super_block *old_sb = mount_info->cloned->sb;
2279 	struct nfs_server *server = NFS_SB(sb);
2280 
2281 	sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2282 	sb->s_blocksize = old_sb->s_blocksize;
2283 	sb->s_maxbytes = old_sb->s_maxbytes;
2284 	sb->s_xattr = old_sb->s_xattr;
2285 	sb->s_op = old_sb->s_op;
2286 	sb->s_time_gran = 1;
2287 
2288 	if (server->nfs_client->rpc_ops->version != 2) {
2289 		/* The VFS shouldn't apply the umask to mode bits. We will do
2290 		 * so ourselves when necessary.
2291 		 */
2292 		sb->s_flags |= MS_POSIXACL;
2293 	}
2294 
2295  	nfs_initialise_sb(sb);
2296 }
2297 
2298 #define NFS_MOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2299 		| NFS_MOUNT_SECURE \
2300 		| NFS_MOUNT_TCP \
2301 		| NFS_MOUNT_VER3 \
2302 		| NFS_MOUNT_KERBEROS \
2303 		| NFS_MOUNT_NONLM \
2304 		| NFS_MOUNT_BROKEN_SUID \
2305 		| NFS_MOUNT_STRICTLOCK \
2306 		| NFS_MOUNT_UNSHARED \
2307 		| NFS_MOUNT_NORESVPORT \
2308 		| NFS_MOUNT_LEGACY_INTERFACE)
2309 
2310 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2311 {
2312 	const struct nfs_server *a = s->s_fs_info;
2313 	const struct rpc_clnt *clnt_a = a->client;
2314 	const struct rpc_clnt *clnt_b = b->client;
2315 
2316 	if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2317 		goto Ebusy;
2318 	if (a->nfs_client != b->nfs_client)
2319 		goto Ebusy;
2320 	if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2321 		goto Ebusy;
2322 	if (a->wsize != b->wsize)
2323 		goto Ebusy;
2324 	if (a->rsize != b->rsize)
2325 		goto Ebusy;
2326 	if (a->acregmin != b->acregmin)
2327 		goto Ebusy;
2328 	if (a->acregmax != b->acregmax)
2329 		goto Ebusy;
2330 	if (a->acdirmin != b->acdirmin)
2331 		goto Ebusy;
2332 	if (a->acdirmax != b->acdirmax)
2333 		goto Ebusy;
2334 	if (b->flags & NFS_MOUNT_SECFLAVOUR &&
2335 	   clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2336 		goto Ebusy;
2337 	return 1;
2338 Ebusy:
2339 	return 0;
2340 }
2341 
2342 struct nfs_sb_mountdata {
2343 	struct nfs_server *server;
2344 	int mntflags;
2345 };
2346 
2347 static int nfs_set_super(struct super_block *s, void *data)
2348 {
2349 	struct nfs_sb_mountdata *sb_mntdata = data;
2350 	struct nfs_server *server = sb_mntdata->server;
2351 	int ret;
2352 
2353 	s->s_flags = sb_mntdata->mntflags;
2354 	s->s_fs_info = server;
2355 	s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2356 	ret = set_anon_super(s, server);
2357 	if (ret == 0)
2358 		server->s_dev = s->s_dev;
2359 	return ret;
2360 }
2361 
2362 static int nfs_compare_super_address(struct nfs_server *server1,
2363 				     struct nfs_server *server2)
2364 {
2365 	struct sockaddr *sap1, *sap2;
2366 
2367 	sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2368 	sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2369 
2370 	if (sap1->sa_family != sap2->sa_family)
2371 		return 0;
2372 
2373 	switch (sap1->sa_family) {
2374 	case AF_INET: {
2375 		struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2376 		struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2377 		if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2378 			return 0;
2379 		if (sin1->sin_port != sin2->sin_port)
2380 			return 0;
2381 		break;
2382 	}
2383 	case AF_INET6: {
2384 		struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2385 		struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2386 		if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2387 			return 0;
2388 		if (sin1->sin6_port != sin2->sin6_port)
2389 			return 0;
2390 		break;
2391 	}
2392 	default:
2393 		return 0;
2394 	}
2395 
2396 	return 1;
2397 }
2398 
2399 static int nfs_compare_super(struct super_block *sb, void *data)
2400 {
2401 	struct nfs_sb_mountdata *sb_mntdata = data;
2402 	struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2403 	int mntflags = sb_mntdata->mntflags;
2404 
2405 	if (!nfs_compare_super_address(old, server))
2406 		return 0;
2407 	/* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2408 	if (old->flags & NFS_MOUNT_UNSHARED)
2409 		return 0;
2410 	if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2411 		return 0;
2412 	return nfs_compare_mount_options(sb, server, mntflags);
2413 }
2414 
2415 #ifdef CONFIG_NFS_FSCACHE
2416 static void nfs_get_cache_cookie(struct super_block *sb,
2417 				 struct nfs_parsed_mount_data *parsed,
2418 				 struct nfs_clone_mount *cloned)
2419 {
2420 	struct nfs_server *nfss = NFS_SB(sb);
2421 	char *uniq = NULL;
2422 	int ulen = 0;
2423 
2424 	nfss->fscache_key = NULL;
2425 	nfss->fscache = NULL;
2426 
2427 	if (parsed) {
2428 		if (!(parsed->options & NFS_OPTION_FSCACHE))
2429 			return;
2430 		if (parsed->fscache_uniq) {
2431 			uniq = parsed->fscache_uniq;
2432 			ulen = strlen(parsed->fscache_uniq);
2433 		}
2434 	} else if (cloned) {
2435 		struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2436 		if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2437 			return;
2438 		if (mnt_s->fscache_key) {
2439 			uniq = mnt_s->fscache_key->key.uniquifier;
2440 			ulen = mnt_s->fscache_key->key.uniq_len;
2441 		};
2442 	} else
2443 		return;
2444 
2445 	nfs_fscache_get_super_cookie(sb, uniq, ulen);
2446 }
2447 #else
2448 static void nfs_get_cache_cookie(struct super_block *sb,
2449 				 struct nfs_parsed_mount_data *parsed,
2450 				 struct nfs_clone_mount *cloned)
2451 {
2452 }
2453 #endif
2454 
2455 static int nfs_bdi_register(struct nfs_server *server)
2456 {
2457 	return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2458 }
2459 
2460 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2461 			struct nfs_mount_info *mount_info)
2462 {
2463 	int error;
2464 	unsigned long kflags = 0, kflags_out = 0;
2465 	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2466 		kflags |= SECURITY_LSM_NATIVE_LABELS;
2467 
2468 	error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2469 						kflags, &kflags_out);
2470 	if (error)
2471 		goto err;
2472 
2473 	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2474 		!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2475 		NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2476 err:
2477 	return error;
2478 }
2479 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2480 
2481 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2482 			  struct nfs_mount_info *mount_info)
2483 {
2484 	/* clone any lsm security options from the parent to the new sb */
2485 	if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2486 		return -ESTALE;
2487 	return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2488 }
2489 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2490 
2491 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2492 				   int flags, const char *dev_name,
2493 				   struct nfs_mount_info *mount_info,
2494 				   struct nfs_subversion *nfs_mod)
2495 {
2496 	struct super_block *s;
2497 	struct dentry *mntroot = ERR_PTR(-ENOMEM);
2498 	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2499 	struct nfs_sb_mountdata sb_mntdata = {
2500 		.mntflags = flags,
2501 		.server = server,
2502 	};
2503 	int error;
2504 
2505 	if (server->flags & NFS_MOUNT_UNSHARED)
2506 		compare_super = NULL;
2507 
2508 	/* -o noac implies -o sync */
2509 	if (server->flags & NFS_MOUNT_NOAC)
2510 		sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2511 
2512 	if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2513 		if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
2514 			sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2515 
2516 	/* Get a superblock - note that we may end up sharing one that already exists */
2517 	s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2518 	if (IS_ERR(s)) {
2519 		mntroot = ERR_CAST(s);
2520 		goto out_err_nosb;
2521 	}
2522 
2523 	if (s->s_fs_info != server) {
2524 		nfs_free_server(server);
2525 		server = NULL;
2526 	} else {
2527 		error = nfs_bdi_register(server);
2528 		if (error) {
2529 			mntroot = ERR_PTR(error);
2530 			goto error_splat_bdi;
2531 		}
2532 	}
2533 
2534 	if (!s->s_root) {
2535 		/* initial superblock/root creation */
2536 		mount_info->fill_super(s, mount_info);
2537 		nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2538 	}
2539 
2540 	mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2541 	if (IS_ERR(mntroot))
2542 		goto error_splat_super;
2543 
2544 	error = mount_info->set_security(s, mntroot, mount_info);
2545 	if (error)
2546 		goto error_splat_root;
2547 
2548 	s->s_flags |= MS_ACTIVE;
2549 
2550 out:
2551 	return mntroot;
2552 
2553 out_err_nosb:
2554 	nfs_free_server(server);
2555 	goto out;
2556 
2557 error_splat_root:
2558 	dput(mntroot);
2559 	mntroot = ERR_PTR(error);
2560 error_splat_super:
2561 	if (server && !s->s_root)
2562 		bdi_unregister(&server->backing_dev_info);
2563 error_splat_bdi:
2564 	deactivate_locked_super(s);
2565 	goto out;
2566 }
2567 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2568 
2569 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2570 	int flags, const char *dev_name, void *raw_data)
2571 {
2572 	struct nfs_mount_info mount_info = {
2573 		.fill_super = nfs_fill_super,
2574 		.set_security = nfs_set_sb_security,
2575 	};
2576 	struct dentry *mntroot = ERR_PTR(-ENOMEM);
2577 	struct nfs_subversion *nfs_mod;
2578 	int error;
2579 
2580 	mount_info.parsed = nfs_alloc_parsed_mount_data();
2581 	mount_info.mntfh = nfs_alloc_fhandle();
2582 	if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2583 		goto out;
2584 
2585 	/* Validate the mount data */
2586 	error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2587 	if (error == NFS_TEXT_DATA)
2588 		error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2589 	if (error < 0) {
2590 		mntroot = ERR_PTR(error);
2591 		goto out;
2592 	}
2593 
2594 	nfs_mod = get_nfs_version(mount_info.parsed->version);
2595 	if (IS_ERR(nfs_mod)) {
2596 		mntroot = ERR_CAST(nfs_mod);
2597 		goto out;
2598 	}
2599 
2600 	mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2601 
2602 	put_nfs_version(nfs_mod);
2603 out:
2604 	nfs_free_parsed_mount_data(mount_info.parsed);
2605 	nfs_free_fhandle(mount_info.mntfh);
2606 	return mntroot;
2607 }
2608 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2609 
2610 /*
2611  * Ensure that we unregister the bdi before kill_anon_super
2612  * releases the device name
2613  */
2614 void nfs_put_super(struct super_block *s)
2615 {
2616 	struct nfs_server *server = NFS_SB(s);
2617 
2618 	bdi_unregister(&server->backing_dev_info);
2619 }
2620 EXPORT_SYMBOL_GPL(nfs_put_super);
2621 
2622 /*
2623  * Destroy an NFS2/3 superblock
2624  */
2625 void nfs_kill_super(struct super_block *s)
2626 {
2627 	struct nfs_server *server = NFS_SB(s);
2628 
2629 	kill_anon_super(s);
2630 	nfs_fscache_release_super_cookie(s);
2631 	nfs_free_server(server);
2632 }
2633 EXPORT_SYMBOL_GPL(nfs_kill_super);
2634 
2635 /*
2636  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2637  */
2638 static struct dentry *
2639 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2640 		const char *dev_name, void *raw_data)
2641 {
2642 	struct nfs_clone_mount *data = raw_data;
2643 	struct nfs_mount_info mount_info = {
2644 		.fill_super = nfs_clone_super,
2645 		.set_security = nfs_clone_sb_security,
2646 		.cloned = data,
2647 	};
2648 	struct nfs_server *server;
2649 	struct dentry *mntroot = ERR_PTR(-ENOMEM);
2650 	struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2651 
2652 	dprintk("--> nfs_xdev_mount()\n");
2653 
2654 	mount_info.mntfh = mount_info.cloned->fh;
2655 
2656 	/* create a new volume representation */
2657 	server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2658 
2659 	if (IS_ERR(server))
2660 		mntroot = ERR_CAST(server);
2661 	else
2662 		mntroot = nfs_fs_mount_common(server, flags,
2663 				dev_name, &mount_info, nfs_mod);
2664 
2665 	dprintk("<-- nfs_xdev_mount() = %ld\n",
2666 			IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2667 	return mntroot;
2668 }
2669 
2670 #if IS_ENABLED(CONFIG_NFS_V4)
2671 
2672 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2673 {
2674 	args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2675 			 NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2676 }
2677 
2678 /*
2679  * Validate NFSv4 mount options
2680  */
2681 static int nfs4_validate_mount_data(void *options,
2682 				    struct nfs_parsed_mount_data *args,
2683 				    const char *dev_name)
2684 {
2685 	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2686 	struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2687 	char *c;
2688 
2689 	if (data == NULL)
2690 		goto out_no_data;
2691 
2692 	args->version = 4;
2693 
2694 	switch (data->version) {
2695 	case 1:
2696 		if (data->host_addrlen > sizeof(args->nfs_server.address))
2697 			goto out_no_address;
2698 		if (data->host_addrlen == 0)
2699 			goto out_no_address;
2700 		args->nfs_server.addrlen = data->host_addrlen;
2701 		if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2702 			return -EFAULT;
2703 		if (!nfs_verify_server_address(sap))
2704 			goto out_no_address;
2705 		args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2706 
2707 		if (data->auth_flavourlen) {
2708 			rpc_authflavor_t pseudoflavor;
2709 			if (data->auth_flavourlen > 1)
2710 				goto out_inval_auth;
2711 			if (copy_from_user(&pseudoflavor,
2712 					   data->auth_flavours,
2713 					   sizeof(pseudoflavor)))
2714 				return -EFAULT;
2715 			nfs_set_auth_parsed_mount_data(args, pseudoflavor);
2716 		} else
2717 			nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
2718 
2719 		c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2720 		if (IS_ERR(c))
2721 			return PTR_ERR(c);
2722 		args->nfs_server.hostname = c;
2723 
2724 		c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2725 		if (IS_ERR(c))
2726 			return PTR_ERR(c);
2727 		args->nfs_server.export_path = c;
2728 		dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2729 
2730 		c = strndup_user(data->client_addr.data, 16);
2731 		if (IS_ERR(c))
2732 			return PTR_ERR(c);
2733 		args->client_address = c;
2734 
2735 		/*
2736 		 * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2737 		 * can deal with.
2738 		 */
2739 
2740 		args->flags	= data->flags & NFS4_MOUNT_FLAGMASK;
2741 		args->rsize	= data->rsize;
2742 		args->wsize	= data->wsize;
2743 		args->timeo	= data->timeo;
2744 		args->retrans	= data->retrans;
2745 		args->acregmin	= data->acregmin;
2746 		args->acregmax	= data->acregmax;
2747 		args->acdirmin	= data->acdirmin;
2748 		args->acdirmax	= data->acdirmax;
2749 		args->nfs_server.protocol = data->proto;
2750 		nfs_validate_transport_protocol(args);
2751 		if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2752 			goto out_invalid_transport_udp;
2753 
2754 		break;
2755 	default:
2756 		return NFS_TEXT_DATA;
2757 	}
2758 
2759 	return 0;
2760 
2761 out_no_data:
2762 	dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2763 	return -EINVAL;
2764 
2765 out_inval_auth:
2766 	dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2767 		 data->auth_flavourlen);
2768 	return -EINVAL;
2769 
2770 out_no_address:
2771 	dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2772 	return -EINVAL;
2773 
2774 out_invalid_transport_udp:
2775 	dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2776 	return -EINVAL;
2777 }
2778 
2779 /*
2780  * NFS v4 module parameters need to stay in the
2781  * NFS client for backwards compatibility
2782  */
2783 unsigned int nfs_callback_set_tcpport;
2784 unsigned short nfs_callback_tcpport;
2785 /* Default cache timeout is 10 minutes */
2786 unsigned int nfs_idmap_cache_timeout = 600;
2787 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2788 bool nfs4_disable_idmapping = true;
2789 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2790 unsigned short send_implementation_id = 1;
2791 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2792 bool recover_lost_locks = false;
2793 
2794 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2795 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2796 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2797 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2798 EXPORT_SYMBOL_GPL(max_session_slots);
2799 EXPORT_SYMBOL_GPL(send_implementation_id);
2800 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2801 EXPORT_SYMBOL_GPL(recover_lost_locks);
2802 
2803 #define NFS_CALLBACK_MAXPORTNR (65535U)
2804 
2805 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2806 {
2807 	unsigned long num;
2808 	int ret;
2809 
2810 	if (!val)
2811 		return -EINVAL;
2812 	ret = kstrtoul(val, 0, &num);
2813 	if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2814 		return -EINVAL;
2815 	*((unsigned int *)kp->arg) = num;
2816 	return 0;
2817 }
2818 static struct kernel_param_ops param_ops_portnr = {
2819 	.set = param_set_portnr,
2820 	.get = param_get_uint,
2821 };
2822 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2823 
2824 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2825 module_param(nfs_idmap_cache_timeout, int, 0644);
2826 module_param(nfs4_disable_idmapping, bool, 0644);
2827 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2828 			NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2829 MODULE_PARM_DESC(nfs4_disable_idmapping,
2830 		"Turn off NFSv4 idmapping when using 'sec=sys'");
2831 module_param(max_session_slots, ushort, 0644);
2832 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2833 		"requests the client will negotiate");
2834 module_param(send_implementation_id, ushort, 0644);
2835 MODULE_PARM_DESC(send_implementation_id,
2836 		"Send implementation ID with NFSv4.1 exchange_id");
2837 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2838 
2839 module_param(recover_lost_locks, bool, 0644);
2840 MODULE_PARM_DESC(recover_lost_locks,
2841 		 "If the server reports that a lock might be lost, "
2842 		 "try to recover it risking data corruption.");
2843 
2844 
2845 #endif /* CONFIG_NFS_V4 */
2846