blob: ca20d3cc260908b485f7d3bf4279ad3d718d97c4 [file] [log] [blame]
David Howellsf7b422b2006-06-09 09:34:33 -04001/*
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 *
David Howells54ceac42006-08-22 20:06:13 -040016 * - 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())
David Howellsf7b422b2006-06-09 09:34:33 -040021 */
22
David Howellsf7b422b2006-06-09 09:34:33 -040023#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>
Adrian Bunkb5d5dfb2007-02-12 00:53:40 -080047#include <linux/magic.h>
David Howellsf7b422b2006-06-09 09:34:33 -040048
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
David Howellsf7b422b2006-06-09 09:34:33 -040060static void nfs_umount_begin(struct vfsmount *, int);
Trond Myklebust816724e2006-06-24 08:41:41 -040061static int nfs_statfs(struct dentry *, struct kstatfs *);
David Howellsf7b422b2006-06-09 09:34:33 -040062static int nfs_show_options(struct seq_file *, struct vfsmount *);
63static int nfs_show_stats(struct seq_file *, struct vfsmount *);
Trond Myklebust816724e2006-06-24 08:41:41 -040064static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
David Howells54ceac42006-08-22 20:06:13 -040065static int nfs_xdev_get_sb(struct file_system_type *fs_type,
Trond Myklebust816724e2006-06-24 08:41:41 -040066 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
David Howellsf7b422b2006-06-09 09:34:33 -040067static void nfs_kill_super(struct super_block *);
68
69static 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,
Mark Fasheh349457c2006-09-08 14:22:21 -070074 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
David Howellsf7b422b2006-06-09 09:34:33 -040075};
76
David Howells54ceac42006-08-22 20:06:13 -040077struct file_system_type nfs_xdev_fs_type = {
David Howellsf7b422b2006-06-09 09:34:33 -040078 .owner = THIS_MODULE,
79 .name = "nfs",
David Howells54ceac42006-08-22 20:06:13 -040080 .get_sb = nfs_xdev_get_sb,
David Howellsf7b422b2006-06-09 09:34:33 -040081 .kill_sb = nfs_kill_super,
Mark Fasheh349457c2006-09-08 14:22:21 -070082 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
David Howellsf7b422b2006-06-09 09:34:33 -040083};
84
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -080085static const struct super_operations nfs_sops = {
David Howellsf7b422b2006-06-09 09:34:33 -040086 .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
Trond Myklebust816724e2006-06-24 08:41:41 -040097static int nfs4_get_sb(struct file_system_type *fs_type,
98 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
David Howells54ceac42006-08-22 20:06:13 -040099static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
100 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
101static int nfs4_referral_get_sb(struct file_system_type *fs_type,
102 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
David Howellsf7b422b2006-06-09 09:34:33 -0400103static void nfs4_kill_super(struct super_block *sb);
104
105static 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,
Mark Fasheh349457c2006-09-08 14:22:21 -0700110 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
David Howellsf7b422b2006-06-09 09:34:33 -0400111};
112
David Howells54ceac42006-08-22 20:06:13 -0400113struct file_system_type nfs4_xdev_fs_type = {
David Howellsf7b422b2006-06-09 09:34:33 -0400114 .owner = THIS_MODULE,
115 .name = "nfs4",
David Howells54ceac42006-08-22 20:06:13 -0400116 .get_sb = nfs4_xdev_get_sb,
David Howellsf7b422b2006-06-09 09:34:33 -0400117 .kill_sb = nfs4_kill_super,
Mark Fasheh349457c2006-09-08 14:22:21 -0700118 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
David Howellsf7b422b2006-06-09 09:34:33 -0400119};
120
David Howells54ceac42006-08-22 20:06:13 -0400121struct file_system_type nfs4_referral_fs_type = {
David Howellsf7b422b2006-06-09 09:34:33 -0400122 .owner = THIS_MODULE,
123 .name = "nfs4",
David Howells54ceac42006-08-22 20:06:13 -0400124 .get_sb = nfs4_referral_get_sb,
David Howellsf7b422b2006-06-09 09:34:33 -0400125 .kill_sb = nfs4_kill_super,
Mark Fasheh349457c2006-09-08 14:22:21 -0700126 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
David Howellsf7b422b2006-06-09 09:34:33 -0400127};
128
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800129static const struct super_operations nfs4_sops = {
David Howellsf7b422b2006-06-09 09:34:33 -0400130 .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
Trond Myklebust979df722006-07-25 11:28:19 -0400141static struct shrinker *acl_shrinker;
142
David Howellsf7b422b2006-06-09 09:34:33 -0400143/*
144 * Register the NFS filesystems
145 */
146int __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
David Howellsf7b422b2006-06-09 09:34:33 -0400154 ret = nfs_register_sysctl();
155 if (ret < 0)
156 goto error_1;
Peter Zijlstra89a09142007-03-16 13:38:26 -0800157#ifdef CONFIG_NFS_V4
David Howellsf7b422b2006-06-09 09:34:33 -0400158 ret = register_filesystem(&nfs4_fs_type);
159 if (ret < 0)
160 goto error_2;
161#endif
Trond Myklebust979df722006-07-25 11:28:19 -0400162 acl_shrinker = set_shrinker(DEFAULT_SEEKS, nfs_access_cache_shrinker);
David Howellsf7b422b2006-06-09 09:34:33 -0400163 return 0;
164
165#ifdef CONFIG_NFS_V4
166error_2:
167 nfs_unregister_sysctl();
Peter Zijlstra89a09142007-03-16 13:38:26 -0800168#endif
David Howellsf7b422b2006-06-09 09:34:33 -0400169error_1:
170 unregister_filesystem(&nfs_fs_type);
David Howellsf7b422b2006-06-09 09:34:33 -0400171error_0:
172 return ret;
173}
174
175/*
176 * Unregister the NFS filesystems
177 */
178void __exit unregister_nfs_fs(void)
179{
Trond Myklebust979df722006-07-25 11:28:19 -0400180 if (acl_shrinker != NULL)
181 remove_shrinker(acl_shrinker);
David Howellsf7b422b2006-06-09 09:34:33 -0400182#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 */
Trond Myklebust816724e2006-06-24 08:41:41 -0400192static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
David Howellsf7b422b2006-06-09 09:34:33 -0400193{
David Howells0c7d90c2006-08-22 20:06:10 -0400194 struct nfs_server *server = NFS_SB(dentry->d_sb);
David Howellsf7b422b2006-06-09 09:34:33 -0400195 unsigned char blockbits;
196 unsigned long blockres;
David Howells0c7d90c2006-08-22 20:06:10 -0400197 struct nfs_fh *fh = NFS_FH(dentry->d_inode);
David Howellsf7b422b2006-06-09 09:34:33 -0400198 struct nfs_fattr fattr;
199 struct nfs_fsstat res = {
200 .fattr = &fattr,
201 };
202 int error;
203
204 lock_kernel();
205
David Howells8fa5c002006-08-22 20:06:12 -0400206 error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
David Howellsf7b422b2006-06-09 09:34:33 -0400207 if (error < 0)
208 goto out_err;
Amnon Aaronsohn1a0ba9a2007-04-09 22:05:26 -0700209 buf->f_type = NFS_SUPER_MAGIC;
David Howellsf7b422b2006-06-09 09:34:33 -0400210
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 */
David Howells0c7d90c2006-08-22 20:06:10 -0400216 buf->f_frsize = dentry->d_sb->s_blocksize;
David Howellsf7b422b2006-06-09 09:34:33 -0400217
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 */
David Howells0c7d90c2006-08-22 20:06:10 -0400225 buf->f_bsize = dentry->d_sb->s_blocksize;
226 blockbits = dentry->d_sb->s_blocksize_bits;
David Howellsf7b422b2006-06-09 09:34:33 -0400227 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;
Amnon Aaronsohn1a0ba9a2007-04-09 22:05:26 -0700236
David Howellsf7b422b2006-06-09 09:34:33 -0400237 unlock_kernel();
238 return 0;
239
240 out_err:
241 dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
Amnon Aaronsohn1a0ba9a2007-04-09 22:05:26 -0700242 unlock_kernel();
243 return error;
David Howellsf7b422b2006-06-09 09:34:33 -0400244}
245
David Howells7d4e2742006-08-22 20:06:07 -0400246/*
247 * Map the security flavour number to a name
248 */
Trond Myklebust81039f12006-06-09 09:34:34 -0400249static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
250{
David Howells7d4e2742006-08-22 20:06:07 -0400251 static const struct {
Trond Myklebust81039f12006-06-09 09:34:34 -0400252 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 { -1, "unknown" }
267 };
268 int i;
269
270 for (i=0; sec_flavours[i].flavour != -1; i++) {
271 if (sec_flavours[i].flavour == flavour)
272 break;
273 }
274 return sec_flavours[i].str;
275}
276
David Howellsf7b422b2006-06-09 09:34:33 -0400277/*
278 * Describe the mount options in force on this server representation
279 */
280static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults)
281{
David Howells509de812006-08-22 20:06:11 -0400282 static const struct proc_nfs_info {
David Howellsf7b422b2006-06-09 09:34:33 -0400283 int flag;
David Howells509de812006-08-22 20:06:11 -0400284 const char *str;
285 const char *nostr;
David Howellsf7b422b2006-06-09 09:34:33 -0400286 } 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", "" },
Steve Dickson74dd34e2007-04-14 17:01:15 -0400293 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
David Howellsf7b422b2006-06-09 09:34:33 -0400294 { 0, NULL, NULL }
295 };
David Howells509de812006-08-22 20:06:11 -0400296 const struct proc_nfs_info *nfs_infop;
David Howells8fa5c002006-08-22 20:06:12 -0400297 struct nfs_client *clp = nfss->nfs_client;
David Howellsf7b422b2006-06-09 09:34:33 -0400298 char buf[12];
David Howells509de812006-08-22 20:06:11 -0400299 const char *proto;
David Howellsf7b422b2006-06-09 09:34:33 -0400300
David Howells8fa5c002006-08-22 20:06:12 -0400301 seq_printf(m, ",vers=%d", clp->rpc_ops->version);
David Howellsf7b422b2006-06-09 09:34:33 -0400302 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);
David Howells5006a762006-08-22 20:06:12 -0400330 seq_printf(m, ",timeo=%lu", 10U * clp->retrans_timeo / HZ);
331 seq_printf(m, ",retrans=%u", clp->retrans_count);
Trond Myklebust81039f12006-06-09 09:34:34 -0400332 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
David Howellsf7b422b2006-06-09 09:34:33 -0400333}
334
335/*
336 * Describe the mount options on this VFS mountpoint
337 */
338static 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=");
David Howells54ceac42006-08-22 20:06:13 -0400345 seq_escape(m, nfss->nfs_client->cl_hostname, " \t\n\\");
David Howellsf7b422b2006-06-09 09:34:33 -0400346
347 return 0;
348}
349
350/*
351 * Present statistical information for this VFS mountpoint
352 */
353static 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
David Howells8fa5c002006-08-22 20:06:12 -0400382 if (nfss->nfs_client->cl_nfsversion == 4) {
David Howellsf7b422b2006-06-09 09:34:33 -0400383 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
David Howells54ceac42006-08-22 20:06:13 -0400429 * in response to xdev traversals and referrals
David Howellsf7b422b2006-06-09 09:34:33 -0400430 */
431static void nfs_umount_begin(struct vfsmount *vfsmnt, int flags)
432{
David Howellsf7b422b2006-06-09 09:34:33 -0400433 shrink_submounts(vfsmnt, &nfs_automount_list);
David Howellsf7b422b2006-06-09 09:34:33 -0400434}
435
436/*
David Howells54ceac42006-08-22 20:06:13 -0400437 * Validate the NFS2/NFS3 mount data
438 * - fills in the mount root filehandle
David Howellsf7b422b2006-06-09 09:34:33 -0400439 */
David Howells54ceac42006-08-22 20:06:13 -0400440static int nfs_validate_mount_data(struct nfs_mount_data *data,
441 struct nfs_fh *mntfh)
David Howellsf7b422b2006-06-09 09:34:33 -0400442{
David Howellsf7b422b2006-06-09 09:34:33 -0400443 if (data == NULL) {
444 dprintk("%s: missing data argument\n", __FUNCTION__);
David Howells54ceac42006-08-22 20:06:13 -0400445 return -EINVAL;
David Howellsf7b422b2006-06-09 09:34:33 -0400446 }
David Howells54ceac42006-08-22 20:06:13 -0400447
David Howellsf7b422b2006-06-09 09:34:33 -0400448 if (data->version <= 0 || data->version > NFS_MOUNT_VERSION) {
449 dprintk("%s: bad mount version\n", __FUNCTION__);
David Howells54ceac42006-08-22 20:06:13 -0400450 return -EINVAL;
David Howellsf7b422b2006-06-09 09:34:33 -0400451 }
David Howells54ceac42006-08-22 20:06:13 -0400452
David Howellsf7b422b2006-06-09 09:34:33 -0400453 switch (data->version) {
454 case 1:
455 data->namlen = 0;
456 case 2:
457 data->bsize = 0;
458 case 3:
459 if (data->flags & NFS_MOUNT_VER3) {
460 dprintk("%s: mount structure version %d does not support NFSv3\n",
461 __FUNCTION__,
462 data->version);
David Howells54ceac42006-08-22 20:06:13 -0400463 return -EINVAL;
David Howellsf7b422b2006-06-09 09:34:33 -0400464 }
465 data->root.size = NFS2_FHSIZE;
466 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
467 case 4:
468 if (data->flags & NFS_MOUNT_SECFLAVOUR) {
469 dprintk("%s: mount structure version %d does not support strong security\n",
470 __FUNCTION__,
471 data->version);
David Howells54ceac42006-08-22 20:06:13 -0400472 return -EINVAL;
David Howellsf7b422b2006-06-09 09:34:33 -0400473 }
474 case 5:
475 memset(data->context, 0, sizeof(data->context));
476 }
David Howells54ceac42006-08-22 20:06:13 -0400477
Trond Myklebust36b15c52006-08-22 20:06:14 -0400478 /* Set the pseudoflavor */
479 if (!(data->flags & NFS_MOUNT_SECFLAVOUR))
480 data->pseudoflavor = RPC_AUTH_UNIX;
481
David Howellsf7b422b2006-06-09 09:34:33 -0400482#ifndef CONFIG_NFS_V3
483 /* If NFSv3 is not compiled in, return -EPROTONOSUPPORT */
David Howellsf7b422b2006-06-09 09:34:33 -0400484 if (data->flags & NFS_MOUNT_VER3) {
485 dprintk("%s: NFSv3 not compiled into kernel\n", __FUNCTION__);
David Howells54ceac42006-08-22 20:06:13 -0400486 return -EPROTONOSUPPORT;
David Howellsf7b422b2006-06-09 09:34:33 -0400487 }
488#endif /* CONFIG_NFS_V3 */
489
David Howellsf7b422b2006-06-09 09:34:33 -0400490 /* We now require that the mount process passes the remote address */
David Howells54ceac42006-08-22 20:06:13 -0400491 if (data->addr.sin_addr.s_addr == INADDR_ANY) {
David Howellsf7b422b2006-06-09 09:34:33 -0400492 dprintk("%s: mount program didn't pass remote address!\n",
David Howells54ceac42006-08-22 20:06:13 -0400493 __FUNCTION__);
494 return -EINVAL;
David Howellsf7b422b2006-06-09 09:34:33 -0400495 }
496
David Howells54ceac42006-08-22 20:06:13 -0400497 /* Prepare the root filehandle */
498 if (data->flags & NFS_MOUNT_VER3)
499 mntfh->size = data->root.size;
500 else
501 mntfh->size = NFS2_FHSIZE;
502
503 if (mntfh->size > sizeof(mntfh->data)) {
504 dprintk("%s: invalid root filehandle\n", __FUNCTION__);
505 return -EINVAL;
506 }
507
508 memcpy(mntfh->data, data->root.data, mntfh->size);
509 if (mntfh->size < sizeof(mntfh->data))
510 memset(mntfh->data + mntfh->size, 0,
511 sizeof(mntfh->data) - mntfh->size);
512
513 return 0;
514}
515
516/*
517 * Initialise the common bits of the superblock
518 */
519static inline void nfs_initialise_sb(struct super_block *sb)
520{
521 struct nfs_server *server = NFS_SB(sb);
522
523 sb->s_magic = NFS_SUPER_MAGIC;
524
525 /* We probably want something more informative here */
526 snprintf(sb->s_id, sizeof(sb->s_id),
527 "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
528
529 if (sb->s_blocksize == 0)
530 sb->s_blocksize = nfs_block_bits(server->wsize,
531 &sb->s_blocksize_bits);
532
533 if (server->flags & NFS_MOUNT_NOAC)
534 sb->s_flags |= MS_SYNCHRONOUS;
535
536 nfs_super_set_maxbytes(sb, server->maxfilesize);
537}
538
539/*
540 * Finish setting up an NFS2/3 superblock
541 */
542static void nfs_fill_super(struct super_block *sb, struct nfs_mount_data *data)
543{
544 struct nfs_server *server = NFS_SB(sb);
545
546 sb->s_blocksize_bits = 0;
547 sb->s_blocksize = 0;
548 if (data->bsize)
549 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
550
551 if (server->flags & NFS_MOUNT_VER3) {
552 /* The VFS shouldn't apply the umask to mode bits. We will do
553 * so ourselves when necessary.
554 */
555 sb->s_flags |= MS_POSIXACL;
556 sb->s_time_gran = 1;
557 }
558
559 sb->s_op = &nfs_sops;
560 nfs_initialise_sb(sb);
561}
562
563/*
564 * Finish setting up a cloned NFS2/3 superblock
565 */
566static void nfs_clone_super(struct super_block *sb,
567 const struct super_block *old_sb)
568{
569 struct nfs_server *server = NFS_SB(sb);
570
571 sb->s_blocksize_bits = old_sb->s_blocksize_bits;
572 sb->s_blocksize = old_sb->s_blocksize;
573 sb->s_maxbytes = old_sb->s_maxbytes;
574
575 if (server->flags & NFS_MOUNT_VER3) {
576 /* The VFS shouldn't apply the umask to mode bits. We will do
577 * so ourselves when necessary.
578 */
579 sb->s_flags |= MS_POSIXACL;
580 sb->s_time_gran = 1;
581 }
582
583 sb->s_op = old_sb->s_op;
584 nfs_initialise_sb(sb);
585}
586
587static int nfs_set_super(struct super_block *s, void *_server)
588{
589 struct nfs_server *server = _server;
590 int ret;
591
592 s->s_fs_info = server;
593 ret = set_anon_super(s, server);
594 if (ret == 0)
595 server->s_dev = s->s_dev;
596 return ret;
597}
598
599static int nfs_compare_super(struct super_block *sb, void *data)
600{
601 struct nfs_server *server = data, *old = NFS_SB(sb);
602
603 if (old->nfs_client != server->nfs_client)
604 return 0;
605 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
606 return 0;
607 return 1;
608}
609
610static int nfs_get_sb(struct file_system_type *fs_type,
611 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
612{
613 struct nfs_server *server = NULL;
614 struct super_block *s;
615 struct nfs_fh mntfh;
616 struct nfs_mount_data *data = raw_data;
617 struct dentry *mntroot;
618 int error;
619
620 /* Validate the mount data */
621 error = nfs_validate_mount_data(data, &mntfh);
622 if (error < 0)
623 return error;
624
625 /* Get a volume representation */
626 server = nfs_create_server(data, &mntfh);
627 if (IS_ERR(server)) {
628 error = PTR_ERR(server);
629 goto out_err_noserver;
630 }
631
632 /* Get a superblock - note that we may end up sharing one that already exists */
David Howellsf7b422b2006-06-09 09:34:33 -0400633 s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
Trond Myklebust816724e2006-06-24 08:41:41 -0400634 if (IS_ERR(s)) {
635 error = PTR_ERR(s);
David Howells54ceac42006-08-22 20:06:13 -0400636 goto out_err_nosb;
Trond Myklebust816724e2006-06-24 08:41:41 -0400637 }
638
David Howells54ceac42006-08-22 20:06:13 -0400639 if (s->s_fs_info != server) {
640 nfs_free_server(server);
641 server = NULL;
David Howellsf7b422b2006-06-09 09:34:33 -0400642 }
David Howells54ceac42006-08-22 20:06:13 -0400643
644 if (!s->s_root) {
645 /* initial superblock/root creation */
646 s->s_flags = flags;
647 nfs_fill_super(s, data);
648 }
649
650 mntroot = nfs_get_root(s, &mntfh);
651 if (IS_ERR(mntroot)) {
652 error = PTR_ERR(mntroot);
653 goto error_splat_super;
654 }
655
David Howellsf7b422b2006-06-09 09:34:33 -0400656 s->s_flags |= MS_ACTIVE;
David Howells54ceac42006-08-22 20:06:13 -0400657 mnt->mnt_sb = s;
658 mnt->mnt_root = mntroot;
659 return 0;
Trond Myklebust816724e2006-06-24 08:41:41 -0400660
David Howells54ceac42006-08-22 20:06:13 -0400661out_err_nosb:
662 nfs_free_server(server);
Trond Myklebust816724e2006-06-24 08:41:41 -0400663out_err_noserver:
664 return error;
David Howells54ceac42006-08-22 20:06:13 -0400665
666error_splat_super:
667 up_write(&s->s_umount);
668 deactivate_super(s);
669 return error;
David Howellsf7b422b2006-06-09 09:34:33 -0400670}
671
David Howells54ceac42006-08-22 20:06:13 -0400672/*
673 * Destroy an NFS2/3 superblock
674 */
David Howellsf7b422b2006-06-09 09:34:33 -0400675static void nfs_kill_super(struct super_block *s)
676{
677 struct nfs_server *server = NFS_SB(s);
678
679 kill_anon_super(s);
David Howells54ceac42006-08-22 20:06:13 -0400680 nfs_free_server(server);
David Howellsf7b422b2006-06-09 09:34:33 -0400681}
682
David Howells54ceac42006-08-22 20:06:13 -0400683/*
684 * Clone an NFS2/3 server record on xdev traversal (FSID-change)
685 */
686static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
687 const char *dev_name, void *raw_data,
688 struct vfsmount *mnt)
David Howellsf7b422b2006-06-09 09:34:33 -0400689{
690 struct nfs_clone_mount *data = raw_data;
David Howells54ceac42006-08-22 20:06:13 -0400691 struct super_block *s;
692 struct nfs_server *server;
693 struct dentry *mntroot;
694 int error;
695
696 dprintk("--> nfs_xdev_get_sb()\n");
697
698 /* create a new volume representation */
699 server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
700 if (IS_ERR(server)) {
701 error = PTR_ERR(server);
702 goto out_err_noserver;
703 }
704
705 /* Get a superblock - note that we may end up sharing one that already exists */
706 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
707 if (IS_ERR(s)) {
708 error = PTR_ERR(s);
709 goto out_err_nosb;
710 }
711
712 if (s->s_fs_info != server) {
713 nfs_free_server(server);
714 server = NULL;
715 }
716
717 if (!s->s_root) {
718 /* initial superblock/root creation */
719 s->s_flags = flags;
720 nfs_clone_super(s, data->sb);
721 }
722
723 mntroot = nfs_get_root(s, data->fh);
724 if (IS_ERR(mntroot)) {
725 error = PTR_ERR(mntroot);
726 goto error_splat_super;
727 }
728
729 s->s_flags |= MS_ACTIVE;
730 mnt->mnt_sb = s;
731 mnt->mnt_root = mntroot;
732
733 dprintk("<-- nfs_xdev_get_sb() = 0\n");
734 return 0;
735
736out_err_nosb:
737 nfs_free_server(server);
738out_err_noserver:
739 dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
740 return error;
741
742error_splat_super:
743 up_write(&s->s_umount);
744 deactivate_super(s);
745 dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
746 return error;
David Howellsf7b422b2006-06-09 09:34:33 -0400747}
748
749#ifdef CONFIG_NFS_V4
David Howells54ceac42006-08-22 20:06:13 -0400750
751/*
752 * Finish setting up a cloned NFS4 superblock
753 */
754static void nfs4_clone_super(struct super_block *sb,
755 const struct super_block *old_sb)
David Howellsf7b422b2006-06-09 09:34:33 -0400756{
David Howells54ceac42006-08-22 20:06:13 -0400757 sb->s_blocksize_bits = old_sb->s_blocksize_bits;
758 sb->s_blocksize = old_sb->s_blocksize;
759 sb->s_maxbytes = old_sb->s_maxbytes;
760 sb->s_time_gran = 1;
761 sb->s_op = old_sb->s_op;
762 nfs_initialise_sb(sb);
David Howellsf7b422b2006-06-09 09:34:33 -0400763}
764
765/*
766 * Set up an NFS4 superblock
767 */
David Howells54ceac42006-08-22 20:06:13 -0400768static void nfs4_fill_super(struct super_block *sb)
David Howellsf7b422b2006-06-09 09:34:33 -0400769{
David Howellsf7b422b2006-06-09 09:34:33 -0400770 sb->s_time_gran = 1;
David Howellsf7b422b2006-06-09 09:34:33 -0400771 sb->s_op = &nfs4_sops;
David Howells54ceac42006-08-22 20:06:13 -0400772 nfs_initialise_sb(sb);
David Howellsf7b422b2006-06-09 09:34:33 -0400773}
774
David Howells54ceac42006-08-22 20:06:13 -0400775static void *nfs_copy_user_string(char *dst, struct nfs_string *src, int maxlen)
David Howellsf7b422b2006-06-09 09:34:33 -0400776{
777 void *p = NULL;
778
779 if (!src->len)
780 return ERR_PTR(-EINVAL);
781 if (src->len < maxlen)
782 maxlen = src->len;
783 if (dst == NULL) {
784 p = dst = kmalloc(maxlen + 1, GFP_KERNEL);
785 if (p == NULL)
786 return ERR_PTR(-ENOMEM);
787 }
788 if (copy_from_user(dst, src->data, maxlen)) {
789 kfree(p);
790 return ERR_PTR(-EFAULT);
791 }
792 dst[maxlen] = '\0';
793 return dst;
794}
795
David Howells54ceac42006-08-22 20:06:13 -0400796/*
797 * Get the superblock for an NFS4 mountpoint
798 */
Trond Myklebust816724e2006-06-24 08:41:41 -0400799static int nfs4_get_sb(struct file_system_type *fs_type,
800 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
David Howellsf7b422b2006-06-09 09:34:33 -0400801{
David Howellsf7b422b2006-06-09 09:34:33 -0400802 struct nfs4_mount_data *data = raw_data;
David Howells54ceac42006-08-22 20:06:13 -0400803 struct super_block *s;
804 struct nfs_server *server;
805 struct sockaddr_in addr;
806 rpc_authflavor_t authflavour;
807 struct nfs_fh mntfh;
808 struct dentry *mntroot;
809 char *mntpath = NULL, *hostname = NULL, ip_addr[16];
David Howellsf7b422b2006-06-09 09:34:33 -0400810 void *p;
David Howells54ceac42006-08-22 20:06:13 -0400811 int error;
David Howellsf7b422b2006-06-09 09:34:33 -0400812
813 if (data == NULL) {
814 dprintk("%s: missing data argument\n", __FUNCTION__);
Trond Myklebust816724e2006-06-24 08:41:41 -0400815 return -EINVAL;
David Howellsf7b422b2006-06-09 09:34:33 -0400816 }
817 if (data->version <= 0 || data->version > NFS4_MOUNT_VERSION) {
818 dprintk("%s: bad mount version\n", __FUNCTION__);
Trond Myklebust816724e2006-06-24 08:41:41 -0400819 return -EINVAL;
David Howellsf7b422b2006-06-09 09:34:33 -0400820 }
821
David Howells54ceac42006-08-22 20:06:13 -0400822 /* We now require that the mount process passes the remote address */
823 if (data->host_addrlen != sizeof(addr))
824 return -EINVAL;
825
826 if (copy_from_user(&addr, data->host_addr, sizeof(addr)))
827 return -EFAULT;
828
829 if (addr.sin_family != AF_INET ||
830 addr.sin_addr.s_addr == INADDR_ANY
831 ) {
832 dprintk("%s: mount program didn't pass remote IP address!\n",
833 __FUNCTION__);
834 return -EINVAL;
835 }
Trond Myklebust51b6ded2006-09-15 16:31:56 -0400836 /* RFC3530: The default port for NFS is 2049 */
837 if (addr.sin_port == 0)
Trond Myklebust575b5c72006-10-19 23:28:37 -0700838 addr.sin_port = htons(NFS_PORT);
David Howells54ceac42006-08-22 20:06:13 -0400839
840 /* Grab the authentication type */
841 authflavour = RPC_AUTH_UNIX;
842 if (data->auth_flavourlen != 0) {
843 if (data->auth_flavourlen != 1) {
844 dprintk("%s: Invalid number of RPC auth flavours %d.\n",
845 __FUNCTION__, data->auth_flavourlen);
846 error = -EINVAL;
847 goto out_err_noserver;
848 }
849
850 if (copy_from_user(&authflavour, data->auth_flavours,
851 sizeof(authflavour))) {
852 error = -EFAULT;
853 goto out_err_noserver;
854 }
855 }
David Howellsf7b422b2006-06-09 09:34:33 -0400856
857 p = nfs_copy_user_string(NULL, &data->hostname, 256);
858 if (IS_ERR(p))
859 goto out_err;
David Howells54ceac42006-08-22 20:06:13 -0400860 hostname = p;
David Howellsf7b422b2006-06-09 09:34:33 -0400861
862 p = nfs_copy_user_string(NULL, &data->mnt_path, 1024);
863 if (IS_ERR(p))
864 goto out_err;
David Howells54ceac42006-08-22 20:06:13 -0400865 mntpath = p;
David Howellsf7b422b2006-06-09 09:34:33 -0400866
David Howells54ceac42006-08-22 20:06:13 -0400867 dprintk("MNTPATH: %s\n", mntpath);
868
869 p = nfs_copy_user_string(ip_addr, &data->client_addr,
870 sizeof(ip_addr) - 1);
David Howellsf7b422b2006-06-09 09:34:33 -0400871 if (IS_ERR(p))
872 goto out_err;
873
David Howells54ceac42006-08-22 20:06:13 -0400874 /* Get a volume representation */
875 server = nfs4_create_server(data, hostname, &addr, mntpath, ip_addr,
876 authflavour, &mntfh);
877 if (IS_ERR(server)) {
878 error = PTR_ERR(server);
879 goto out_err_noserver;
David Howellsf7b422b2006-06-09 09:34:33 -0400880 }
881
David Howells54ceac42006-08-22 20:06:13 -0400882 /* Get a superblock - note that we may end up sharing one that already exists */
883 s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
Trond Myklebust816724e2006-06-24 08:41:41 -0400884 if (IS_ERR(s)) {
885 error = PTR_ERR(s);
David Howellsf7b422b2006-06-09 09:34:33 -0400886 goto out_free;
Trond Myklebust816724e2006-06-24 08:41:41 -0400887 }
888
Trond Myklebust5dd31772006-08-24 01:03:05 -0400889 if (s->s_fs_info != server) {
890 nfs_free_server(server);
891 server = NULL;
892 }
893
David Howells54ceac42006-08-22 20:06:13 -0400894 if (!s->s_root) {
895 /* initial superblock/root creation */
896 s->s_flags = flags;
David Howells54ceac42006-08-22 20:06:13 -0400897 nfs4_fill_super(s);
Trond Myklebust816724e2006-06-24 08:41:41 -0400898 }
David Howellsf7b422b2006-06-09 09:34:33 -0400899
David Howells54ceac42006-08-22 20:06:13 -0400900 mntroot = nfs4_get_root(s, &mntfh);
901 if (IS_ERR(mntroot)) {
902 error = PTR_ERR(mntroot);
903 goto error_splat_super;
David Howellsf7b422b2006-06-09 09:34:33 -0400904 }
David Howells54ceac42006-08-22 20:06:13 -0400905
David Howellsf7b422b2006-06-09 09:34:33 -0400906 s->s_flags |= MS_ACTIVE;
David Howells54ceac42006-08-22 20:06:13 -0400907 mnt->mnt_sb = s;
908 mnt->mnt_root = mntroot;
909 kfree(mntpath);
910 kfree(hostname);
911 return 0;
912
David Howellsf7b422b2006-06-09 09:34:33 -0400913out_err:
Trond Myklebust816724e2006-06-24 08:41:41 -0400914 error = PTR_ERR(p);
David Howells54ceac42006-08-22 20:06:13 -0400915 goto out_err_noserver;
916
David Howellsf7b422b2006-06-09 09:34:33 -0400917out_free:
David Howells54ceac42006-08-22 20:06:13 -0400918 nfs_free_server(server);
919out_err_noserver:
920 kfree(mntpath);
921 kfree(hostname);
Trond Myklebust816724e2006-06-24 08:41:41 -0400922 return error;
David Howells54ceac42006-08-22 20:06:13 -0400923
924error_splat_super:
925 up_write(&s->s_umount);
926 deactivate_super(s);
927 goto out_err_noserver;
David Howellsf7b422b2006-06-09 09:34:33 -0400928}
929
930static void nfs4_kill_super(struct super_block *sb)
931{
932 struct nfs_server *server = NFS_SB(sb);
933
934 nfs_return_all_delegations(sb);
935 kill_anon_super(sb);
936
937 nfs4_renewd_prepare_shutdown(server);
David Howells54ceac42006-08-22 20:06:13 -0400938 nfs_free_server(server);
David Howellsf7b422b2006-06-09 09:34:33 -0400939}
940
941/*
David Howells54ceac42006-08-22 20:06:13 -0400942 * Clone an NFS4 server record on xdev traversal (FSID-change)
David Howellsf7b422b2006-06-09 09:34:33 -0400943 */
David Howells54ceac42006-08-22 20:06:13 -0400944static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
945 const char *dev_name, void *raw_data,
946 struct vfsmount *mnt)
David Howellsf7b422b2006-06-09 09:34:33 -0400947{
948 struct nfs_clone_mount *data = raw_data;
David Howells54ceac42006-08-22 20:06:13 -0400949 struct super_block *s;
950 struct nfs_server *server;
951 struct dentry *mntroot;
952 int error;
953
954 dprintk("--> nfs4_xdev_get_sb()\n");
955
956 /* create a new volume representation */
957 server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
958 if (IS_ERR(server)) {
959 error = PTR_ERR(server);
960 goto out_err_noserver;
961 }
962
963 /* Get a superblock - note that we may end up sharing one that already exists */
964 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
965 if (IS_ERR(s)) {
966 error = PTR_ERR(s);
967 goto out_err_nosb;
968 }
969
970 if (s->s_fs_info != server) {
971 nfs_free_server(server);
972 server = NULL;
973 }
974
975 if (!s->s_root) {
976 /* initial superblock/root creation */
977 s->s_flags = flags;
978 nfs4_clone_super(s, data->sb);
979 }
980
981 mntroot = nfs4_get_root(s, data->fh);
982 if (IS_ERR(mntroot)) {
983 error = PTR_ERR(mntroot);
984 goto error_splat_super;
985 }
986
987 s->s_flags |= MS_ACTIVE;
988 mnt->mnt_sb = s;
989 mnt->mnt_root = mntroot;
990
991 dprintk("<-- nfs4_xdev_get_sb() = 0\n");
992 return 0;
993
994out_err_nosb:
995 nfs_free_server(server);
996out_err_noserver:
997 dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
998 return error;
999
1000error_splat_super:
1001 up_write(&s->s_umount);
1002 deactivate_super(s);
1003 dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
1004 return error;
David Howellsf7b422b2006-06-09 09:34:33 -04001005}
1006
David Howells54ceac42006-08-22 20:06:13 -04001007/*
1008 * Create an NFS4 server record on referral traversal
1009 */
1010static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
1011 const char *dev_name, void *raw_data,
1012 struct vfsmount *mnt)
David Howellsf7b422b2006-06-09 09:34:33 -04001013{
1014 struct nfs_clone_mount *data = raw_data;
David Howells54ceac42006-08-22 20:06:13 -04001015 struct super_block *s;
1016 struct nfs_server *server;
1017 struct dentry *mntroot;
1018 struct nfs_fh mntfh;
1019 int error;
1020
1021 dprintk("--> nfs4_referral_get_sb()\n");
1022
1023 /* create a new volume representation */
1024 server = nfs4_create_referral_server(data, &mntfh);
1025 if (IS_ERR(server)) {
1026 error = PTR_ERR(server);
1027 goto out_err_noserver;
1028 }
1029
1030 /* Get a superblock - note that we may end up sharing one that already exists */
1031 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
1032 if (IS_ERR(s)) {
1033 error = PTR_ERR(s);
1034 goto out_err_nosb;
1035 }
1036
1037 if (s->s_fs_info != server) {
1038 nfs_free_server(server);
1039 server = NULL;
1040 }
1041
1042 if (!s->s_root) {
1043 /* initial superblock/root creation */
1044 s->s_flags = flags;
1045 nfs4_fill_super(s);
1046 }
1047
Trond Myklebustf2d0d852007-02-02 14:46:09 -08001048 mntroot = nfs4_get_root(s, &mntfh);
David Howells54ceac42006-08-22 20:06:13 -04001049 if (IS_ERR(mntroot)) {
1050 error = PTR_ERR(mntroot);
1051 goto error_splat_super;
1052 }
1053
1054 s->s_flags |= MS_ACTIVE;
1055 mnt->mnt_sb = s;
1056 mnt->mnt_root = mntroot;
1057
1058 dprintk("<-- nfs4_referral_get_sb() = 0\n");
1059 return 0;
1060
1061out_err_nosb:
1062 nfs_free_server(server);
1063out_err_noserver:
1064 dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
1065 return error;
1066
1067error_splat_super:
1068 up_write(&s->s_umount);
1069 deactivate_super(s);
1070 dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
1071 return error;
David Howellsf7b422b2006-06-09 09:34:33 -04001072}
1073
David Howells54ceac42006-08-22 20:06:13 -04001074#endif /* CONFIG_NFS_V4 */