xref: /linux/fs/nfs/inode.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  *  linux/fs/nfs/inode.c
3  *
4  *  Copyright (C) 1992  Rick Sladkey
5  *
6  *  nfs inode and 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  */
15 
16 #include <linux/config.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 
20 #include <linux/time.h>
21 #include <linux/kernel.h>
22 #include <linux/mm.h>
23 #include <linux/string.h>
24 #include <linux/stat.h>
25 #include <linux/errno.h>
26 #include <linux/unistd.h>
27 #include <linux/sunrpc/clnt.h>
28 #include <linux/sunrpc/stats.h>
29 #include <linux/sunrpc/metrics.h>
30 #include <linux/nfs_fs.h>
31 #include <linux/nfs_mount.h>
32 #include <linux/nfs4_mount.h>
33 #include <linux/lockd/bind.h>
34 #include <linux/smp_lock.h>
35 #include <linux/seq_file.h>
36 #include <linux/mount.h>
37 #include <linux/nfs_idmap.h>
38 #include <linux/vfs.h>
39 
40 #include <asm/system.h>
41 #include <asm/uaccess.h>
42 
43 #include "nfs4_fs.h"
44 #include "callback.h"
45 #include "delegation.h"
46 #include "iostat.h"
47 
48 #define NFSDBG_FACILITY		NFSDBG_VFS
49 #define NFS_PARANOIA 1
50 
51 /* Maximum number of readahead requests
52  * FIXME: this should really be a sysctl so that users may tune it to suit
53  *        their needs. People that do NFS over a slow network, might for
54  *        instance want to reduce it to something closer to 1 for improved
55  *        interactive response.
56  */
57 #define NFS_MAX_READAHEAD	(RPC_DEF_SLOT_TABLE - 1)
58 
59 static void nfs_invalidate_inode(struct inode *);
60 static int nfs_update_inode(struct inode *, struct nfs_fattr *);
61 
62 static struct inode *nfs_alloc_inode(struct super_block *sb);
63 static void nfs_destroy_inode(struct inode *);
64 static int nfs_write_inode(struct inode *,int);
65 static void nfs_delete_inode(struct inode *);
66 static void nfs_clear_inode(struct inode *);
67 static void nfs_umount_begin(struct super_block *);
68 static int  nfs_statfs(struct super_block *, struct kstatfs *);
69 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
70 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
71 static void nfs_zap_acl_cache(struct inode *);
72 
73 static struct rpc_program	nfs_program;
74 
75 static struct super_operations nfs_sops = {
76 	.alloc_inode	= nfs_alloc_inode,
77 	.destroy_inode	= nfs_destroy_inode,
78 	.write_inode	= nfs_write_inode,
79 	.delete_inode	= nfs_delete_inode,
80 	.statfs		= nfs_statfs,
81 	.clear_inode	= nfs_clear_inode,
82 	.umount_begin	= nfs_umount_begin,
83 	.show_options	= nfs_show_options,
84 	.show_stats	= nfs_show_stats,
85 };
86 
87 /*
88  * RPC cruft for NFS
89  */
90 static struct rpc_stat		nfs_rpcstat = {
91 	.program		= &nfs_program
92 };
93 static struct rpc_version *	nfs_version[] = {
94 	NULL,
95 	NULL,
96 	&nfs_version2,
97 #if defined(CONFIG_NFS_V3)
98 	&nfs_version3,
99 #elif defined(CONFIG_NFS_V4)
100 	NULL,
101 #endif
102 #if defined(CONFIG_NFS_V4)
103 	&nfs_version4,
104 #endif
105 };
106 
107 static struct rpc_program	nfs_program = {
108 	.name			= "nfs",
109 	.number			= NFS_PROGRAM,
110 	.nrvers			= ARRAY_SIZE(nfs_version),
111 	.version		= nfs_version,
112 	.stats			= &nfs_rpcstat,
113 	.pipe_dir_name		= "/nfs",
114 };
115 
116 #ifdef CONFIG_NFS_V3_ACL
117 static struct rpc_stat		nfsacl_rpcstat = { &nfsacl_program };
118 static struct rpc_version *	nfsacl_version[] = {
119 	[3]			= &nfsacl_version3,
120 };
121 
122 struct rpc_program		nfsacl_program = {
123 	.name =			"nfsacl",
124 	.number =		NFS_ACL_PROGRAM,
125 	.nrvers =		ARRAY_SIZE(nfsacl_version),
126 	.version =		nfsacl_version,
127 	.stats =		&nfsacl_rpcstat,
128 };
129 #endif  /* CONFIG_NFS_V3_ACL */
130 
131 static inline unsigned long
132 nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
133 {
134 	return nfs_fileid_to_ino_t(fattr->fileid);
135 }
136 
137 static int
138 nfs_write_inode(struct inode *inode, int sync)
139 {
140 	int flags = sync ? FLUSH_SYNC : 0;
141 	int ret;
142 
143 	ret = nfs_commit_inode(inode, flags);
144 	if (ret < 0)
145 		return ret;
146 	return 0;
147 }
148 
149 static void
150 nfs_delete_inode(struct inode * inode)
151 {
152 	dprintk("NFS: delete_inode(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
153 
154 	truncate_inode_pages(&inode->i_data, 0);
155 
156 	nfs_wb_all(inode);
157 	/*
158 	 * The following should never happen...
159 	 */
160 	if (nfs_have_writebacks(inode)) {
161 		printk(KERN_ERR "nfs_delete_inode: inode %ld has pending RPC requests\n", inode->i_ino);
162 	}
163 
164 	clear_inode(inode);
165 }
166 
167 static void
168 nfs_clear_inode(struct inode *inode)
169 {
170 	struct nfs_inode *nfsi = NFS_I(inode);
171 	struct rpc_cred *cred;
172 
173 	nfs_wb_all(inode);
174 	BUG_ON (!list_empty(&nfsi->open_files));
175 	nfs_zap_acl_cache(inode);
176 	cred = nfsi->cache_access.cred;
177 	if (cred)
178 		put_rpccred(cred);
179 	BUG_ON(atomic_read(&nfsi->data_updates) != 0);
180 }
181 
182 void
183 nfs_umount_begin(struct super_block *sb)
184 {
185 	struct rpc_clnt	*rpc = NFS_SB(sb)->client;
186 
187 	/* -EIO all pending I/O */
188 	if (!IS_ERR(rpc))
189 		rpc_killall_tasks(rpc);
190 	rpc = NFS_SB(sb)->client_acl;
191 	if (!IS_ERR(rpc))
192 		rpc_killall_tasks(rpc);
193 }
194 
195 
196 static inline unsigned long
197 nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
198 {
199 	/* make sure blocksize is a power of two */
200 	if ((bsize & (bsize - 1)) || nrbitsp) {
201 		unsigned char	nrbits;
202 
203 		for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
204 			;
205 		bsize = 1 << nrbits;
206 		if (nrbitsp)
207 			*nrbitsp = nrbits;
208 	}
209 
210 	return bsize;
211 }
212 
213 /*
214  * Calculate the number of 512byte blocks used.
215  */
216 static inline unsigned long
217 nfs_calc_block_size(u64 tsize)
218 {
219 	loff_t used = (tsize + 511) >> 9;
220 	return (used > ULONG_MAX) ? ULONG_MAX : used;
221 }
222 
223 /*
224  * Compute and set NFS server blocksize
225  */
226 static inline unsigned long
227 nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
228 {
229 	if (bsize < NFS_MIN_FILE_IO_SIZE)
230 		bsize = NFS_DEF_FILE_IO_SIZE;
231 	else if (bsize >= NFS_MAX_FILE_IO_SIZE)
232 		bsize = NFS_MAX_FILE_IO_SIZE;
233 
234 	return nfs_block_bits(bsize, nrbitsp);
235 }
236 
237 /*
238  * Obtain the root inode of the file system.
239  */
240 static struct inode *
241 nfs_get_root(struct super_block *sb, struct nfs_fh *rootfh, struct nfs_fsinfo *fsinfo)
242 {
243 	struct nfs_server	*server = NFS_SB(sb);
244 	int			error;
245 
246 	error = server->rpc_ops->getroot(server, rootfh, fsinfo);
247 	if (error < 0) {
248 		dprintk("nfs_get_root: getattr error = %d\n", -error);
249 		return ERR_PTR(error);
250 	}
251 
252 	return nfs_fhget(sb, rootfh, fsinfo->fattr);
253 }
254 
255 /*
256  * Do NFS version-independent mount processing, and sanity checking
257  */
258 static int
259 nfs_sb_init(struct super_block *sb, rpc_authflavor_t authflavor)
260 {
261 	struct nfs_server	*server;
262 	struct inode		*root_inode;
263 	struct nfs_fattr	fattr;
264 	struct nfs_fsinfo	fsinfo = {
265 					.fattr = &fattr,
266 				};
267 	struct nfs_pathconf pathinfo = {
268 			.fattr = &fattr,
269 	};
270 	int no_root_error = 0;
271 	unsigned long max_rpc_payload;
272 
273 	/* We probably want something more informative here */
274 	snprintf(sb->s_id, sizeof(sb->s_id), "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
275 
276 	server = NFS_SB(sb);
277 
278 	sb->s_magic      = NFS_SUPER_MAGIC;
279 
280 	server->io_stats = nfs_alloc_iostats();
281 	if (server->io_stats == NULL)
282 		return -ENOMEM;
283 
284 	root_inode = nfs_get_root(sb, &server->fh, &fsinfo);
285 	/* Did getting the root inode fail? */
286 	if (IS_ERR(root_inode)) {
287 		no_root_error = PTR_ERR(root_inode);
288 		goto out_no_root;
289 	}
290 	sb->s_root = d_alloc_root(root_inode);
291 	if (!sb->s_root) {
292 		no_root_error = -ENOMEM;
293 		goto out_no_root;
294 	}
295 	sb->s_root->d_op = server->rpc_ops->dentry_ops;
296 
297 	/* mount time stamp, in seconds */
298 	server->mount_time = jiffies;
299 
300 	/* Get some general file system info */
301 	if (server->namelen == 0 &&
302 	    server->rpc_ops->pathconf(server, &server->fh, &pathinfo) >= 0)
303 		server->namelen = pathinfo.max_namelen;
304 	/* Work out a lot of parameters */
305 	if (server->rsize == 0)
306 		server->rsize = nfs_block_size(fsinfo.rtpref, NULL);
307 	if (server->wsize == 0)
308 		server->wsize = nfs_block_size(fsinfo.wtpref, NULL);
309 
310 	if (fsinfo.rtmax >= 512 && server->rsize > fsinfo.rtmax)
311 		server->rsize = nfs_block_size(fsinfo.rtmax, NULL);
312 	if (fsinfo.wtmax >= 512 && server->wsize > fsinfo.wtmax)
313 		server->wsize = nfs_block_size(fsinfo.wtmax, NULL);
314 
315 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
316 	if (server->rsize > max_rpc_payload)
317 		server->rsize = max_rpc_payload;
318 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
319 		server->rsize = NFS_MAX_FILE_IO_SIZE;
320 	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
321 
322 	if (server->wsize > max_rpc_payload)
323 		server->wsize = max_rpc_payload;
324 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
325 		server->wsize = NFS_MAX_FILE_IO_SIZE;
326 	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
327 
328 	if (sb->s_blocksize == 0)
329 		sb->s_blocksize = nfs_block_bits(server->wsize,
330 							 &sb->s_blocksize_bits);
331 	server->wtmult = nfs_block_bits(fsinfo.wtmult, NULL);
332 
333 	server->dtsize = nfs_block_size(fsinfo.dtpref, NULL);
334 	if (server->dtsize > PAGE_CACHE_SIZE)
335 		server->dtsize = PAGE_CACHE_SIZE;
336 	if (server->dtsize > server->rsize)
337 		server->dtsize = server->rsize;
338 
339 	if (server->flags & NFS_MOUNT_NOAC) {
340 		server->acregmin = server->acregmax = 0;
341 		server->acdirmin = server->acdirmax = 0;
342 		sb->s_flags |= MS_SYNCHRONOUS;
343 	}
344 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
345 
346 	sb->s_maxbytes = fsinfo.maxfilesize;
347 	if (sb->s_maxbytes > MAX_LFS_FILESIZE)
348 		sb->s_maxbytes = MAX_LFS_FILESIZE;
349 
350 	server->client->cl_intr = (server->flags & NFS_MOUNT_INTR) ? 1 : 0;
351 	server->client->cl_softrtry = (server->flags & NFS_MOUNT_SOFT) ? 1 : 0;
352 
353 	/* We're airborne Set socket buffersize */
354 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
355 	return 0;
356 	/* Yargs. It didn't work out. */
357 out_no_root:
358 	dprintk("nfs_sb_init: get root inode failed: errno %d\n", -no_root_error);
359 	if (!IS_ERR(root_inode))
360 		iput(root_inode);
361 	return no_root_error;
362 }
363 
364 static void nfs_init_timeout_values(struct rpc_timeout *to, int proto, unsigned int timeo, unsigned int retrans)
365 {
366 	to->to_initval = timeo * HZ / 10;
367 	to->to_retries = retrans;
368 	if (!to->to_retries)
369 		to->to_retries = 2;
370 
371 	switch (proto) {
372 	case IPPROTO_TCP:
373 		if (!to->to_initval)
374 			to->to_initval = 60 * HZ;
375 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
376 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
377 		to->to_increment = to->to_initval;
378 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
379 		to->to_exponential = 0;
380 		break;
381 	case IPPROTO_UDP:
382 	default:
383 		if (!to->to_initval)
384 			to->to_initval = 11 * HZ / 10;
385 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
386 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
387 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
388 		to->to_exponential = 1;
389 		break;
390 	}
391 }
392 
393 /*
394  * Create an RPC client handle.
395  */
396 static struct rpc_clnt *
397 nfs_create_client(struct nfs_server *server, const struct nfs_mount_data *data)
398 {
399 	struct rpc_timeout	timeparms;
400 	struct rpc_xprt		*xprt = NULL;
401 	struct rpc_clnt		*clnt = NULL;
402 	int			proto = (data->flags & NFS_MOUNT_TCP) ? IPPROTO_TCP : IPPROTO_UDP;
403 
404 	nfs_init_timeout_values(&timeparms, proto, data->timeo, data->retrans);
405 
406 	server->retrans_timeo = timeparms.to_initval;
407 	server->retrans_count = timeparms.to_retries;
408 
409 	/* create transport and client */
410 	xprt = xprt_create_proto(proto, &server->addr, &timeparms);
411 	if (IS_ERR(xprt)) {
412 		dprintk("%s: cannot create RPC transport. Error = %ld\n",
413 				__FUNCTION__, PTR_ERR(xprt));
414 		return (struct rpc_clnt *)xprt;
415 	}
416 	clnt = rpc_create_client(xprt, server->hostname, &nfs_program,
417 				 server->rpc_ops->version, data->pseudoflavor);
418 	if (IS_ERR(clnt)) {
419 		dprintk("%s: cannot create RPC client. Error = %ld\n",
420 				__FUNCTION__, PTR_ERR(xprt));
421 		goto out_fail;
422 	}
423 
424 	clnt->cl_intr     = 1;
425 	clnt->cl_softrtry = 1;
426 
427 	return clnt;
428 
429 out_fail:
430 	return clnt;
431 }
432 
433 /*
434  * The way this works is that the mount process passes a structure
435  * in the data argument which contains the server's IP address
436  * and the root file handle obtained from the server's mount
437  * daemon. We stash these away in the private superblock fields.
438  */
439 static int
440 nfs_fill_super(struct super_block *sb, struct nfs_mount_data *data, int silent)
441 {
442 	struct nfs_server	*server;
443 	rpc_authflavor_t	authflavor;
444 
445 	server           = NFS_SB(sb);
446 	sb->s_blocksize_bits = 0;
447 	sb->s_blocksize = 0;
448 	if (data->bsize)
449 		sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
450 	if (data->rsize)
451 		server->rsize = nfs_block_size(data->rsize, NULL);
452 	if (data->wsize)
453 		server->wsize = nfs_block_size(data->wsize, NULL);
454 	server->flags    = data->flags & NFS_MOUNT_FLAGMASK;
455 
456 	server->acregmin = data->acregmin*HZ;
457 	server->acregmax = data->acregmax*HZ;
458 	server->acdirmin = data->acdirmin*HZ;
459 	server->acdirmax = data->acdirmax*HZ;
460 
461 	/* Start lockd here, before we might error out */
462 	if (!(server->flags & NFS_MOUNT_NONLM))
463 		lockd_up();
464 
465 	server->namelen  = data->namlen;
466 	server->hostname = kmalloc(strlen(data->hostname) + 1, GFP_KERNEL);
467 	if (!server->hostname)
468 		return -ENOMEM;
469 	strcpy(server->hostname, data->hostname);
470 
471 	/* Check NFS protocol revision and initialize RPC op vector
472 	 * and file handle pool. */
473 #ifdef CONFIG_NFS_V3
474 	if (server->flags & NFS_MOUNT_VER3) {
475 		server->rpc_ops = &nfs_v3_clientops;
476 		server->caps |= NFS_CAP_READDIRPLUS;
477 	} else {
478 		server->rpc_ops = &nfs_v2_clientops;
479 	}
480 #else
481 	server->rpc_ops = &nfs_v2_clientops;
482 #endif
483 
484 	/* Fill in pseudoflavor for mount version < 5 */
485 	if (!(data->flags & NFS_MOUNT_SECFLAVOUR))
486 		data->pseudoflavor = RPC_AUTH_UNIX;
487 	authflavor = data->pseudoflavor;	/* save for sb_init() */
488 	/* XXX maybe we want to add a server->pseudoflavor field */
489 
490 	/* Create RPC client handles */
491 	server->client = nfs_create_client(server, data);
492 	if (IS_ERR(server->client))
493 		return PTR_ERR(server->client);
494 	/* RFC 2623, sec 2.3.2 */
495 	if (authflavor != RPC_AUTH_UNIX) {
496 		struct rpc_auth *auth;
497 
498 		server->client_sys = rpc_clone_client(server->client);
499 		if (IS_ERR(server->client_sys))
500 			return PTR_ERR(server->client_sys);
501 		auth = rpcauth_create(RPC_AUTH_UNIX, server->client_sys);
502 		if (IS_ERR(auth))
503 			return PTR_ERR(auth);
504 	} else {
505 		atomic_inc(&server->client->cl_count);
506 		server->client_sys = server->client;
507 	}
508 	if (server->flags & NFS_MOUNT_VER3) {
509 #ifdef CONFIG_NFS_V3_ACL
510 		if (!(server->flags & NFS_MOUNT_NOACL)) {
511 			server->client_acl = rpc_bind_new_program(server->client, &nfsacl_program, 3);
512 			/* No errors! Assume that Sun nfsacls are supported */
513 			if (!IS_ERR(server->client_acl))
514 				server->caps |= NFS_CAP_ACLS;
515 		}
516 #else
517 		server->flags &= ~NFS_MOUNT_NOACL;
518 #endif /* CONFIG_NFS_V3_ACL */
519 		/*
520 		 * The VFS shouldn't apply the umask to mode bits. We will
521 		 * do so ourselves when necessary.
522 		 */
523 		sb->s_flags |= MS_POSIXACL;
524 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
525 			server->namelen = NFS3_MAXNAMLEN;
526 		sb->s_time_gran = 1;
527 	} else {
528 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
529 			server->namelen = NFS2_MAXNAMLEN;
530 	}
531 
532 	sb->s_op = &nfs_sops;
533 	return nfs_sb_init(sb, authflavor);
534 }
535 
536 static int
537 nfs_statfs(struct super_block *sb, struct kstatfs *buf)
538 {
539 	struct nfs_server *server = NFS_SB(sb);
540 	unsigned char blockbits;
541 	unsigned long blockres;
542 	struct nfs_fh *rootfh = NFS_FH(sb->s_root->d_inode);
543 	struct nfs_fattr fattr;
544 	struct nfs_fsstat res = {
545 			.fattr = &fattr,
546 	};
547 	int error;
548 
549 	lock_kernel();
550 
551 	error = server->rpc_ops->statfs(server, rootfh, &res);
552 	buf->f_type = NFS_SUPER_MAGIC;
553 	if (error < 0)
554 		goto out_err;
555 
556 	/*
557 	 * Current versions of glibc do not correctly handle the
558 	 * case where f_frsize != f_bsize.  Eventually we want to
559 	 * report the value of wtmult in this field.
560 	 */
561 	buf->f_frsize = sb->s_blocksize;
562 
563 	/*
564 	 * On most *nix systems, f_blocks, f_bfree, and f_bavail
565 	 * are reported in units of f_frsize.  Linux hasn't had
566 	 * an f_frsize field in its statfs struct until recently,
567 	 * thus historically Linux's sys_statfs reports these
568 	 * fields in units of f_bsize.
569 	 */
570 	buf->f_bsize = sb->s_blocksize;
571 	blockbits = sb->s_blocksize_bits;
572 	blockres = (1 << blockbits) - 1;
573 	buf->f_blocks = (res.tbytes + blockres) >> blockbits;
574 	buf->f_bfree = (res.fbytes + blockres) >> blockbits;
575 	buf->f_bavail = (res.abytes + blockres) >> blockbits;
576 
577 	buf->f_files = res.tfiles;
578 	buf->f_ffree = res.afiles;
579 
580 	buf->f_namelen = server->namelen;
581  out:
582 	unlock_kernel();
583 	return 0;
584 
585  out_err:
586 	dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
587 	buf->f_bsize = buf->f_blocks = buf->f_bfree = buf->f_bavail = -1;
588 	goto out;
589 
590 }
591 
592 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults)
593 {
594 	static struct proc_nfs_info {
595 		int flag;
596 		char *str;
597 		char *nostr;
598 	} nfs_info[] = {
599 		{ NFS_MOUNT_SOFT, ",soft", ",hard" },
600 		{ NFS_MOUNT_INTR, ",intr", "" },
601 		{ NFS_MOUNT_NOCTO, ",nocto", "" },
602 		{ NFS_MOUNT_NOAC, ",noac", "" },
603 		{ NFS_MOUNT_NONLM, ",nolock", "" },
604 		{ NFS_MOUNT_NOACL, ",noacl", "" },
605 		{ 0, NULL, NULL }
606 	};
607 	struct proc_nfs_info *nfs_infop;
608 	char buf[12];
609 	char *proto;
610 
611 	seq_printf(m, ",vers=%d", nfss->rpc_ops->version);
612 	seq_printf(m, ",rsize=%d", nfss->rsize);
613 	seq_printf(m, ",wsize=%d", nfss->wsize);
614 	if (nfss->acregmin != 3*HZ || showdefaults)
615 		seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
616 	if (nfss->acregmax != 60*HZ || showdefaults)
617 		seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
618 	if (nfss->acdirmin != 30*HZ || showdefaults)
619 		seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
620 	if (nfss->acdirmax != 60*HZ || showdefaults)
621 		seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ);
622 	for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
623 		if (nfss->flags & nfs_infop->flag)
624 			seq_puts(m, nfs_infop->str);
625 		else
626 			seq_puts(m, nfs_infop->nostr);
627 	}
628 	switch (nfss->client->cl_xprt->prot) {
629 		case IPPROTO_TCP:
630 			proto = "tcp";
631 			break;
632 		case IPPROTO_UDP:
633 			proto = "udp";
634 			break;
635 		default:
636 			snprintf(buf, sizeof(buf), "%u", nfss->client->cl_xprt->prot);
637 			proto = buf;
638 	}
639 	seq_printf(m, ",proto=%s", proto);
640 	seq_printf(m, ",timeo=%lu", 10U * nfss->retrans_timeo / HZ);
641 	seq_printf(m, ",retrans=%u", nfss->retrans_count);
642 }
643 
644 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
645 {
646 	struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
647 
648 	nfs_show_mount_options(m, nfss, 0);
649 
650 	seq_puts(m, ",addr=");
651 	seq_escape(m, nfss->hostname, " \t\n\\");
652 
653 	return 0;
654 }
655 
656 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
657 {
658 	int i, cpu;
659 	struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
660 	struct rpc_auth *auth = nfss->client->cl_auth;
661 	struct nfs_iostats totals = { };
662 
663 	seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
664 
665 	/*
666 	 * Display all mount option settings
667 	 */
668 	seq_printf(m, "\n\topts:\t");
669 	seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
670 	seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
671 	seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
672 	seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
673 	nfs_show_mount_options(m, nfss, 1);
674 
675 	seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
676 
677 	seq_printf(m, "\n\tcaps:\t");
678 	seq_printf(m, "caps=0x%x", nfss->caps);
679 	seq_printf(m, ",wtmult=%d", nfss->wtmult);
680 	seq_printf(m, ",dtsize=%d", nfss->dtsize);
681 	seq_printf(m, ",bsize=%d", nfss->bsize);
682 	seq_printf(m, ",namelen=%d", nfss->namelen);
683 
684 #ifdef CONFIG_NFS_V4
685 	if (nfss->rpc_ops->version == 4) {
686 		seq_printf(m, "\n\tnfsv4:\t");
687 		seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
688 		seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
689 		seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
690 	}
691 #endif
692 
693 	/*
694 	 * Display security flavor in effect for this mount
695 	 */
696 	seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor);
697 	if (auth->au_flavor)
698 		seq_printf(m, ",pseudoflavor=%d", auth->au_flavor);
699 
700 	/*
701 	 * Display superblock I/O counters
702 	 */
703 	for_each_possible_cpu(cpu) {
704 		struct nfs_iostats *stats;
705 
706 		preempt_disable();
707 		stats = per_cpu_ptr(nfss->io_stats, cpu);
708 
709 		for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
710 			totals.events[i] += stats->events[i];
711 		for (i = 0; i < __NFSIOS_BYTESMAX; i++)
712 			totals.bytes[i] += stats->bytes[i];
713 
714 		preempt_enable();
715 	}
716 
717 	seq_printf(m, "\n\tevents:\t");
718 	for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
719 		seq_printf(m, "%lu ", totals.events[i]);
720 	seq_printf(m, "\n\tbytes:\t");
721 	for (i = 0; i < __NFSIOS_BYTESMAX; i++)
722 		seq_printf(m, "%Lu ", totals.bytes[i]);
723 	seq_printf(m, "\n");
724 
725 	rpc_print_iostats(m, nfss->client);
726 
727 	return 0;
728 }
729 
730 /**
731  * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
732  */
733 int nfs_sync_mapping(struct address_space *mapping)
734 {
735 	int ret;
736 
737 	if (mapping->nrpages == 0)
738 		return 0;
739 	unmap_mapping_range(mapping, 0, 0, 0);
740 	ret = filemap_write_and_wait(mapping);
741 	if (ret != 0)
742 		goto out;
743 	ret = nfs_wb_all(mapping->host);
744 out:
745 	return ret;
746 }
747 
748 /*
749  * Invalidate the local caches
750  */
751 static void nfs_zap_caches_locked(struct inode *inode)
752 {
753 	struct nfs_inode *nfsi = NFS_I(inode);
754 	int mode = inode->i_mode;
755 
756 	nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
757 
758 	NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode);
759 	NFS_ATTRTIMEO_UPDATE(inode) = jiffies;
760 
761 	memset(NFS_COOKIEVERF(inode), 0, sizeof(NFS_COOKIEVERF(inode)));
762 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))
763 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
764 	else
765 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
766 }
767 
768 void nfs_zap_caches(struct inode *inode)
769 {
770 	spin_lock(&inode->i_lock);
771 	nfs_zap_caches_locked(inode);
772 	spin_unlock(&inode->i_lock);
773 }
774 
775 static void nfs_zap_acl_cache(struct inode *inode)
776 {
777 	void (*clear_acl_cache)(struct inode *);
778 
779 	clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
780 	if (clear_acl_cache != NULL)
781 		clear_acl_cache(inode);
782 	spin_lock(&inode->i_lock);
783 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
784 	spin_unlock(&inode->i_lock);
785 }
786 
787 /*
788  * Invalidate, but do not unhash, the inode.
789  * NB: must be called with inode->i_lock held!
790  */
791 static void nfs_invalidate_inode(struct inode *inode)
792 {
793 	set_bit(NFS_INO_STALE, &NFS_FLAGS(inode));
794 	nfs_zap_caches_locked(inode);
795 }
796 
797 struct nfs_find_desc {
798 	struct nfs_fh		*fh;
799 	struct nfs_fattr	*fattr;
800 };
801 
802 /*
803  * In NFSv3 we can have 64bit inode numbers. In order to support
804  * this, and re-exported directories (also seen in NFSv2)
805  * we are forced to allow 2 different inodes to have the same
806  * i_ino.
807  */
808 static int
809 nfs_find_actor(struct inode *inode, void *opaque)
810 {
811 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
812 	struct nfs_fh		*fh = desc->fh;
813 	struct nfs_fattr	*fattr = desc->fattr;
814 
815 	if (NFS_FILEID(inode) != fattr->fileid)
816 		return 0;
817 	if (nfs_compare_fh(NFS_FH(inode), fh))
818 		return 0;
819 	if (is_bad_inode(inode) || NFS_STALE(inode))
820 		return 0;
821 	return 1;
822 }
823 
824 static int
825 nfs_init_locked(struct inode *inode, void *opaque)
826 {
827 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
828 	struct nfs_fattr	*fattr = desc->fattr;
829 
830 	NFS_FILEID(inode) = fattr->fileid;
831 	nfs_copy_fh(NFS_FH(inode), desc->fh);
832 	return 0;
833 }
834 
835 /* Don't use READDIRPLUS on directories that we believe are too large */
836 #define NFS_LIMIT_READDIRPLUS (8*PAGE_SIZE)
837 
838 /*
839  * This is our front-end to iget that looks up inodes by file handle
840  * instead of inode number.
841  */
842 struct inode *
843 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
844 {
845 	struct nfs_find_desc desc = {
846 		.fh	= fh,
847 		.fattr	= fattr
848 	};
849 	struct inode *inode = ERR_PTR(-ENOENT);
850 	unsigned long hash;
851 
852 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
853 		goto out_no_inode;
854 
855 	if (!fattr->nlink) {
856 		printk("NFS: Buggy server - nlink == 0!\n");
857 		goto out_no_inode;
858 	}
859 
860 	hash = nfs_fattr_to_ino_t(fattr);
861 
862 	inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
863 	if (inode == NULL) {
864 		inode = ERR_PTR(-ENOMEM);
865 		goto out_no_inode;
866 	}
867 
868 	if (inode->i_state & I_NEW) {
869 		struct nfs_inode *nfsi = NFS_I(inode);
870 
871 		/* We set i_ino for the few things that still rely on it,
872 		 * such as stat(2) */
873 		inode->i_ino = hash;
874 
875 		/* We can't support update_atime(), since the server will reset it */
876 		inode->i_flags |= S_NOATIME|S_NOCMTIME;
877 		inode->i_mode = fattr->mode;
878 		/* Why so? Because we want revalidate for devices/FIFOs, and
879 		 * that's precisely what we have in nfs_file_inode_operations.
880 		 */
881 		inode->i_op = NFS_SB(sb)->rpc_ops->file_inode_ops;
882 		if (S_ISREG(inode->i_mode)) {
883 			inode->i_fop = &nfs_file_operations;
884 			inode->i_data.a_ops = &nfs_file_aops;
885 			inode->i_data.backing_dev_info = &NFS_SB(sb)->backing_dev_info;
886 		} else if (S_ISDIR(inode->i_mode)) {
887 			inode->i_op = NFS_SB(sb)->rpc_ops->dir_inode_ops;
888 			inode->i_fop = &nfs_dir_operations;
889 			if (nfs_server_capable(inode, NFS_CAP_READDIRPLUS)
890 			    && fattr->size <= NFS_LIMIT_READDIRPLUS)
891 				set_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
892 		} else if (S_ISLNK(inode->i_mode))
893 			inode->i_op = &nfs_symlink_inode_operations;
894 		else
895 			init_special_inode(inode, inode->i_mode, fattr->rdev);
896 
897 		nfsi->read_cache_jiffies = fattr->time_start;
898 		nfsi->last_updated = jiffies;
899 		inode->i_atime = fattr->atime;
900 		inode->i_mtime = fattr->mtime;
901 		inode->i_ctime = fattr->ctime;
902 		if (fattr->valid & NFS_ATTR_FATTR_V4)
903 			nfsi->change_attr = fattr->change_attr;
904 		inode->i_size = nfs_size_to_loff_t(fattr->size);
905 		inode->i_nlink = fattr->nlink;
906 		inode->i_uid = fattr->uid;
907 		inode->i_gid = fattr->gid;
908 		if (fattr->valid & (NFS_ATTR_FATTR_V3 | NFS_ATTR_FATTR_V4)) {
909 			/*
910 			 * report the blocks in 512byte units
911 			 */
912 			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
913 			inode->i_blksize = inode->i_sb->s_blocksize;
914 		} else {
915 			inode->i_blocks = fattr->du.nfs2.blocks;
916 			inode->i_blksize = fattr->du.nfs2.blocksize;
917 		}
918 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
919 		nfsi->attrtimeo_timestamp = jiffies;
920 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
921 		nfsi->cache_access.cred = NULL;
922 
923 		unlock_new_inode(inode);
924 	} else
925 		nfs_refresh_inode(inode, fattr);
926 	dprintk("NFS: nfs_fhget(%s/%Ld ct=%d)\n",
927 		inode->i_sb->s_id,
928 		(long long)NFS_FILEID(inode),
929 		atomic_read(&inode->i_count));
930 
931 out:
932 	return inode;
933 
934 out_no_inode:
935 	dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
936 	goto out;
937 }
938 
939 #define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET)
940 
941 int
942 nfs_setattr(struct dentry *dentry, struct iattr *attr)
943 {
944 	struct inode *inode = dentry->d_inode;
945 	struct nfs_fattr fattr;
946 	int error;
947 
948 	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
949 
950 	if (attr->ia_valid & ATTR_SIZE) {
951 		if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
952 			attr->ia_valid &= ~ATTR_SIZE;
953 	}
954 
955 	/* Optimization: if the end result is no change, don't RPC */
956 	attr->ia_valid &= NFS_VALID_ATTRS;
957 	if (attr->ia_valid == 0)
958 		return 0;
959 
960 	lock_kernel();
961 	nfs_begin_data_update(inode);
962 	/* Write all dirty data */
963 	filemap_write_and_wait(inode->i_mapping);
964 	nfs_wb_all(inode);
965 	/*
966 	 * Return any delegations if we're going to change ACLs
967 	 */
968 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
969 		nfs_inode_return_delegation(inode);
970 	error = NFS_PROTO(inode)->setattr(dentry, &fattr, attr);
971 	if (error == 0)
972 		nfs_refresh_inode(inode, &fattr);
973 	nfs_end_data_update(inode);
974 	unlock_kernel();
975 	return error;
976 }
977 
978 /**
979  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
980  * @inode: pointer to struct inode
981  * @attr: pointer to struct iattr
982  *
983  * Note: we do this in the *proc.c in order to ensure that
984  *       it works for things like exclusive creates too.
985  */
986 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
987 {
988 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
989 		if ((attr->ia_valid & ATTR_MODE) != 0) {
990 			int mode = attr->ia_mode & S_IALLUGO;
991 			mode |= inode->i_mode & ~S_IALLUGO;
992 			inode->i_mode = mode;
993 		}
994 		if ((attr->ia_valid & ATTR_UID) != 0)
995 			inode->i_uid = attr->ia_uid;
996 		if ((attr->ia_valid & ATTR_GID) != 0)
997 			inode->i_gid = attr->ia_gid;
998 		spin_lock(&inode->i_lock);
999 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1000 		spin_unlock(&inode->i_lock);
1001 	}
1002 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
1003 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
1004 		inode->i_size = attr->ia_size;
1005 		vmtruncate(inode, attr->ia_size);
1006 	}
1007 }
1008 
1009 static int nfs_wait_schedule(void *word)
1010 {
1011 	if (signal_pending(current))
1012 		return -ERESTARTSYS;
1013 	schedule();
1014 	return 0;
1015 }
1016 
1017 /*
1018  * Wait for the inode to get unlocked.
1019  */
1020 static int nfs_wait_on_inode(struct inode *inode)
1021 {
1022 	struct rpc_clnt	*clnt = NFS_CLIENT(inode);
1023 	struct nfs_inode *nfsi = NFS_I(inode);
1024 	sigset_t oldmask;
1025 	int error;
1026 
1027 	rpc_clnt_sigmask(clnt, &oldmask);
1028 	error = wait_on_bit_lock(&nfsi->flags, NFS_INO_REVALIDATING,
1029 					nfs_wait_schedule, TASK_INTERRUPTIBLE);
1030 	rpc_clnt_sigunmask(clnt, &oldmask);
1031 
1032 	return error;
1033 }
1034 
1035 static void nfs_wake_up_inode(struct inode *inode)
1036 {
1037 	struct nfs_inode *nfsi = NFS_I(inode);
1038 
1039 	clear_bit(NFS_INO_REVALIDATING, &nfsi->flags);
1040 	smp_mb__after_clear_bit();
1041 	wake_up_bit(&nfsi->flags, NFS_INO_REVALIDATING);
1042 }
1043 
1044 int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1045 {
1046 	struct inode *inode = dentry->d_inode;
1047 	int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
1048 	int err;
1049 
1050 	/* Flush out writes to the server in order to update c/mtime */
1051 	nfs_sync_inode_wait(inode, 0, 0, FLUSH_NOCOMMIT);
1052 
1053 	/*
1054 	 * We may force a getattr if the user cares about atime.
1055 	 *
1056 	 * Note that we only have to check the vfsmount flags here:
1057 	 *  - NFS always sets S_NOATIME by so checking it would give a
1058 	 *    bogus result
1059 	 *  - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
1060 	 *    no point in checking those.
1061 	 */
1062  	if ((mnt->mnt_flags & MNT_NOATIME) ||
1063  	    ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
1064 		need_atime = 0;
1065 
1066 	if (need_atime)
1067 		err = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1068 	else
1069 		err = nfs_revalidate_inode(NFS_SERVER(inode), inode);
1070 	if (!err)
1071 		generic_fillattr(inode, stat);
1072 	return err;
1073 }
1074 
1075 static struct nfs_open_context *alloc_nfs_open_context(struct vfsmount *mnt, struct dentry *dentry, struct rpc_cred *cred)
1076 {
1077 	struct nfs_open_context *ctx;
1078 
1079 	ctx = (struct nfs_open_context *)kmalloc(sizeof(*ctx), GFP_KERNEL);
1080 	if (ctx != NULL) {
1081 		atomic_set(&ctx->count, 1);
1082 		ctx->dentry = dget(dentry);
1083 		ctx->vfsmnt = mntget(mnt);
1084 		ctx->cred = get_rpccred(cred);
1085 		ctx->state = NULL;
1086 		ctx->lockowner = current->files;
1087 		ctx->error = 0;
1088 		ctx->dir_cookie = 0;
1089 	}
1090 	return ctx;
1091 }
1092 
1093 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
1094 {
1095 	if (ctx != NULL)
1096 		atomic_inc(&ctx->count);
1097 	return ctx;
1098 }
1099 
1100 void put_nfs_open_context(struct nfs_open_context *ctx)
1101 {
1102 	if (atomic_dec_and_test(&ctx->count)) {
1103 		if (!list_empty(&ctx->list)) {
1104 			struct inode *inode = ctx->dentry->d_inode;
1105 			spin_lock(&inode->i_lock);
1106 			list_del(&ctx->list);
1107 			spin_unlock(&inode->i_lock);
1108 		}
1109 		if (ctx->state != NULL)
1110 			nfs4_close_state(ctx->state, ctx->mode);
1111 		if (ctx->cred != NULL)
1112 			put_rpccred(ctx->cred);
1113 		dput(ctx->dentry);
1114 		mntput(ctx->vfsmnt);
1115 		kfree(ctx);
1116 	}
1117 }
1118 
1119 /*
1120  * Ensure that mmap has a recent RPC credential for use when writing out
1121  * shared pages
1122  */
1123 static void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
1124 {
1125 	struct inode *inode = filp->f_dentry->d_inode;
1126 	struct nfs_inode *nfsi = NFS_I(inode);
1127 
1128 	filp->private_data = get_nfs_open_context(ctx);
1129 	spin_lock(&inode->i_lock);
1130 	list_add(&ctx->list, &nfsi->open_files);
1131 	spin_unlock(&inode->i_lock);
1132 }
1133 
1134 /*
1135  * Given an inode, search for an open context with the desired characteristics
1136  */
1137 struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, int mode)
1138 {
1139 	struct nfs_inode *nfsi = NFS_I(inode);
1140 	struct nfs_open_context *pos, *ctx = NULL;
1141 
1142 	spin_lock(&inode->i_lock);
1143 	list_for_each_entry(pos, &nfsi->open_files, list) {
1144 		if (cred != NULL && pos->cred != cred)
1145 			continue;
1146 		if ((pos->mode & mode) == mode) {
1147 			ctx = get_nfs_open_context(pos);
1148 			break;
1149 		}
1150 	}
1151 	spin_unlock(&inode->i_lock);
1152 	return ctx;
1153 }
1154 
1155 static void nfs_file_clear_open_context(struct file *filp)
1156 {
1157 	struct inode *inode = filp->f_dentry->d_inode;
1158 	struct nfs_open_context *ctx = (struct nfs_open_context *)filp->private_data;
1159 
1160 	if (ctx) {
1161 		filp->private_data = NULL;
1162 		spin_lock(&inode->i_lock);
1163 		list_move_tail(&ctx->list, &NFS_I(inode)->open_files);
1164 		spin_unlock(&inode->i_lock);
1165 		put_nfs_open_context(ctx);
1166 	}
1167 }
1168 
1169 /*
1170  * These allocate and release file read/write context information.
1171  */
1172 int nfs_open(struct inode *inode, struct file *filp)
1173 {
1174 	struct nfs_open_context *ctx;
1175 	struct rpc_cred *cred;
1176 
1177 	cred = rpcauth_lookupcred(NFS_CLIENT(inode)->cl_auth, 0);
1178 	if (IS_ERR(cred))
1179 		return PTR_ERR(cred);
1180 	ctx = alloc_nfs_open_context(filp->f_vfsmnt, filp->f_dentry, cred);
1181 	put_rpccred(cred);
1182 	if (ctx == NULL)
1183 		return -ENOMEM;
1184 	ctx->mode = filp->f_mode;
1185 	nfs_file_set_open_context(filp, ctx);
1186 	put_nfs_open_context(ctx);
1187 	return 0;
1188 }
1189 
1190 int nfs_release(struct inode *inode, struct file *filp)
1191 {
1192 	nfs_file_clear_open_context(filp);
1193 	return 0;
1194 }
1195 
1196 /*
1197  * This function is called whenever some part of NFS notices that
1198  * the cached attributes have to be refreshed.
1199  */
1200 int
1201 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1202 {
1203 	int		 status = -ESTALE;
1204 	struct nfs_fattr fattr;
1205 	struct nfs_inode *nfsi = NFS_I(inode);
1206 
1207 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Ld)\n",
1208 		inode->i_sb->s_id, (long long)NFS_FILEID(inode));
1209 
1210 	lock_kernel();
1211 	if (!inode || is_bad_inode(inode))
1212  		goto out_nowait;
1213 	if (NFS_STALE(inode))
1214  		goto out_nowait;
1215 
1216 	status = nfs_wait_on_inode(inode);
1217 	if (status < 0)
1218 		goto out;
1219 	if (NFS_STALE(inode)) {
1220 		status = -ESTALE;
1221 		/* Do we trust the cached ESTALE? */
1222 		if (NFS_ATTRTIMEO(inode) != 0) {
1223 			if (nfsi->cache_validity & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ATIME)) {
1224 				/* no */
1225 			} else
1226 				goto out;
1227 		}
1228 	}
1229 
1230 	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), &fattr);
1231 	if (status != 0) {
1232 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) getattr failed, error=%d\n",
1233 			 inode->i_sb->s_id,
1234 			 (long long)NFS_FILEID(inode), status);
1235 		if (status == -ESTALE) {
1236 			nfs_zap_caches(inode);
1237 			if (!S_ISDIR(inode->i_mode))
1238 				set_bit(NFS_INO_STALE, &NFS_FLAGS(inode));
1239 		}
1240 		goto out;
1241 	}
1242 
1243 	spin_lock(&inode->i_lock);
1244 	status = nfs_update_inode(inode, &fattr);
1245 	if (status) {
1246 		spin_unlock(&inode->i_lock);
1247 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) refresh failed, error=%d\n",
1248 			 inode->i_sb->s_id,
1249 			 (long long)NFS_FILEID(inode), status);
1250 		goto out;
1251 	}
1252 	spin_unlock(&inode->i_lock);
1253 
1254 	nfs_revalidate_mapping(inode, inode->i_mapping);
1255 
1256 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
1257 		nfs_zap_acl_cache(inode);
1258 
1259 	dfprintk(PAGECACHE, "NFS: (%s/%Ld) revalidation complete\n",
1260 		inode->i_sb->s_id,
1261 		(long long)NFS_FILEID(inode));
1262 
1263  out:
1264 	nfs_wake_up_inode(inode);
1265 
1266  out_nowait:
1267 	unlock_kernel();
1268 	return status;
1269 }
1270 
1271 int nfs_attribute_timeout(struct inode *inode)
1272 {
1273 	struct nfs_inode *nfsi = NFS_I(inode);
1274 
1275 	if (nfs_have_delegation(inode, FMODE_READ))
1276 		return 0;
1277 	return time_after(jiffies, nfsi->read_cache_jiffies+nfsi->attrtimeo);
1278 }
1279 
1280 /**
1281  * nfs_revalidate_inode - Revalidate the inode attributes
1282  * @server - pointer to nfs_server struct
1283  * @inode - pointer to inode struct
1284  *
1285  * Updates inode attribute information by retrieving the data from the server.
1286  */
1287 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1288 {
1289 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
1290 	if (!(NFS_I(inode)->cache_validity & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA))
1291 			&& !nfs_attribute_timeout(inode))
1292 		return NFS_STALE(inode) ? -ESTALE : 0;
1293 	return __nfs_revalidate_inode(server, inode);
1294 }
1295 
1296 /**
1297  * nfs_revalidate_mapping - Revalidate the pagecache
1298  * @inode - pointer to host inode
1299  * @mapping - pointer to mapping
1300  */
1301 void nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
1302 {
1303 	struct nfs_inode *nfsi = NFS_I(inode);
1304 
1305 	if (nfsi->cache_validity & NFS_INO_INVALID_DATA) {
1306 		nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
1307 		if (S_ISREG(inode->i_mode))
1308 			nfs_sync_mapping(mapping);
1309 		invalidate_inode_pages2(mapping);
1310 
1311 		spin_lock(&inode->i_lock);
1312 		nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
1313 		if (S_ISDIR(inode->i_mode)) {
1314 			memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
1315 			/* This ensures we revalidate child dentries */
1316 			nfsi->cache_change_attribute = jiffies;
1317 		}
1318 		spin_unlock(&inode->i_lock);
1319 
1320 		dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
1321 				inode->i_sb->s_id,
1322 				(long long)NFS_FILEID(inode));
1323 	}
1324 }
1325 
1326 /**
1327  * nfs_begin_data_update
1328  * @inode - pointer to inode
1329  * Declare that a set of operations will update file data on the server
1330  */
1331 void nfs_begin_data_update(struct inode *inode)
1332 {
1333 	atomic_inc(&NFS_I(inode)->data_updates);
1334 }
1335 
1336 /**
1337  * nfs_end_data_update
1338  * @inode - pointer to inode
1339  * Declare end of the operations that will update file data
1340  * This will mark the inode as immediately needing revalidation
1341  * of its attribute cache.
1342  */
1343 void nfs_end_data_update(struct inode *inode)
1344 {
1345 	struct nfs_inode *nfsi = NFS_I(inode);
1346 
1347 	if (!nfs_have_delegation(inode, FMODE_READ)) {
1348 		/* Directories and symlinks: invalidate page cache */
1349 		if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) {
1350 			spin_lock(&inode->i_lock);
1351 			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
1352 			spin_unlock(&inode->i_lock);
1353 		}
1354 	}
1355 	nfsi->cache_change_attribute = jiffies;
1356 	atomic_dec(&nfsi->data_updates);
1357 }
1358 
1359 static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1360 {
1361 	struct nfs_inode *nfsi = NFS_I(inode);
1362 
1363 	if ((fattr->valid & NFS_ATTR_PRE_CHANGE) != 0
1364 			&& nfsi->change_attr == fattr->pre_change_attr) {
1365 		nfsi->change_attr = fattr->change_attr;
1366 		nfsi->cache_change_attribute = jiffies;
1367 	}
1368 
1369 	/* If we have atomic WCC data, we may update some attributes */
1370 	if ((fattr->valid & NFS_ATTR_WCC) != 0) {
1371 		if (timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
1372 			memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1373 			nfsi->cache_change_attribute = jiffies;
1374 		}
1375 		if (timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
1376 			memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1377 			nfsi->cache_change_attribute = jiffies;
1378 		}
1379 		if (inode->i_size == fattr->pre_size && nfsi->npages == 0) {
1380 			inode->i_size = fattr->size;
1381 			nfsi->cache_change_attribute = jiffies;
1382 		}
1383 	}
1384 }
1385 
1386 /**
1387  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1388  * @inode - pointer to inode
1389  * @fattr - updated attributes
1390  *
1391  * Verifies the attribute cache. If we have just changed the attributes,
1392  * so that fattr carries weak cache consistency data, then it may
1393  * also update the ctime/mtime/change_attribute.
1394  */
1395 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1396 {
1397 	struct nfs_inode *nfsi = NFS_I(inode);
1398 	loff_t cur_size, new_isize;
1399 	int data_unstable;
1400 
1401 
1402 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1403 		return 0;
1404 
1405 	/* Has the inode gone and changed behind our back? */
1406 	if (nfsi->fileid != fattr->fileid
1407 			|| (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
1408 		return -EIO;
1409 	}
1410 
1411 	/* Are we in the process of updating data on the server? */
1412 	data_unstable = nfs_caches_unstable(inode);
1413 
1414 	/* Do atomic weak cache consistency updates */
1415 	nfs_wcc_update_inode(inode, fattr);
1416 
1417 	if ((fattr->valid & NFS_ATTR_FATTR_V4) != 0) {
1418 		if (nfsi->change_attr == fattr->change_attr)
1419 			goto out;
1420 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
1421 		if (!data_unstable)
1422 			nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE;
1423 	}
1424 
1425 	/* Verify a few of the more important attributes */
1426 	if (!timespec_equal(&inode->i_mtime, &fattr->mtime)) {
1427 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
1428 		if (!data_unstable)
1429 			nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE;
1430 	}
1431 
1432 	cur_size = i_size_read(inode);
1433  	new_isize = nfs_size_to_loff_t(fattr->size);
1434 	if (cur_size != new_isize && nfsi->npages == 0)
1435 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1436 
1437 	/* Have any file permissions changed? */
1438 	if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)
1439 			|| inode->i_uid != fattr->uid
1440 			|| inode->i_gid != fattr->gid)
1441 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1442 
1443 	/* Has the link count changed? */
1444 	if (inode->i_nlink != fattr->nlink)
1445 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
1446 
1447 out:
1448 	if (!timespec_equal(&inode->i_atime, &fattr->atime))
1449 		nfsi->cache_validity |= NFS_INO_INVALID_ATIME;
1450 
1451 	nfsi->read_cache_jiffies = fattr->time_start;
1452 	return 0;
1453 }
1454 
1455 /**
1456  * nfs_refresh_inode - try to update the inode attribute cache
1457  * @inode - pointer to inode
1458  * @fattr - updated attributes
1459  *
1460  * Check that an RPC call that returned attributes has not overlapped with
1461  * other recent updates of the inode metadata, then decide whether it is
1462  * safe to do a full update of the inode attributes, or whether just to
1463  * call nfs_check_inode_attributes.
1464  */
1465 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
1466 {
1467 	struct nfs_inode *nfsi = NFS_I(inode);
1468 	int status;
1469 
1470 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1471 		return 0;
1472 	spin_lock(&inode->i_lock);
1473 	nfsi->cache_validity &= ~NFS_INO_REVAL_PAGECACHE;
1474 	if (time_after(fattr->time_start, nfsi->last_updated))
1475 		status = nfs_update_inode(inode, fattr);
1476 	else
1477 		status = nfs_check_inode_attributes(inode, fattr);
1478 
1479 	spin_unlock(&inode->i_lock);
1480 	return status;
1481 }
1482 
1483 /**
1484  * nfs_post_op_update_inode - try to update the inode attribute cache
1485  * @inode - pointer to inode
1486  * @fattr - updated attributes
1487  *
1488  * After an operation that has changed the inode metadata, mark the
1489  * attribute cache as being invalid, then try to update it.
1490  */
1491 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1492 {
1493 	struct nfs_inode *nfsi = NFS_I(inode);
1494 	int status = 0;
1495 
1496 	spin_lock(&inode->i_lock);
1497 	if (unlikely((fattr->valid & NFS_ATTR_FATTR) == 0)) {
1498 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS;
1499 		goto out;
1500 	}
1501 	status = nfs_update_inode(inode, fattr);
1502 out:
1503 	spin_unlock(&inode->i_lock);
1504 	return status;
1505 }
1506 
1507 /*
1508  * Many nfs protocol calls return the new file attributes after
1509  * an operation.  Here we update the inode to reflect the state
1510  * of the server's inode.
1511  *
1512  * This is a bit tricky because we have to make sure all dirty pages
1513  * have been sent off to the server before calling invalidate_inode_pages.
1514  * To make sure no other process adds more write requests while we try
1515  * our best to flush them, we make them sleep during the attribute refresh.
1516  *
1517  * A very similar scenario holds for the dir cache.
1518  */
1519 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1520 {
1521 	struct nfs_inode *nfsi = NFS_I(inode);
1522 	loff_t cur_isize, new_isize;
1523 	unsigned int	invalid = 0;
1524 	int data_stable;
1525 
1526 	dfprintk(VFS, "NFS: %s(%s/%ld ct=%d info=0x%x)\n",
1527 			__FUNCTION__, inode->i_sb->s_id, inode->i_ino,
1528 			atomic_read(&inode->i_count), fattr->valid);
1529 
1530 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1531 		return 0;
1532 
1533 	if (nfsi->fileid != fattr->fileid)
1534 		goto out_fileid;
1535 
1536 	/*
1537 	 * Make sure the inode's type hasn't changed.
1538 	 */
1539 	if ((inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
1540 		goto out_changed;
1541 
1542 	/*
1543 	 * Update the read time so we don't revalidate too often.
1544 	 */
1545 	nfsi->read_cache_jiffies = fattr->time_start;
1546 	nfsi->last_updated = jiffies;
1547 
1548 	/* Are we racing with known updates of the metadata on the server? */
1549 	data_stable = nfs_verify_change_attribute(inode, fattr->time_start);
1550 	if (data_stable)
1551 		nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME);
1552 
1553 	/* Do atomic weak cache consistency updates */
1554 	nfs_wcc_update_inode(inode, fattr);
1555 
1556 	/* Check if our cached file size is stale */
1557  	new_isize = nfs_size_to_loff_t(fattr->size);
1558 	cur_isize = i_size_read(inode);
1559 	if (new_isize != cur_isize) {
1560 		/* Do we perhaps have any outstanding writes? */
1561 		if (nfsi->npages == 0) {
1562 			/* No, but did we race with nfs_end_data_update()? */
1563 			if (data_stable) {
1564 				inode->i_size = new_isize;
1565 				invalid |= NFS_INO_INVALID_DATA;
1566 			}
1567 			invalid |= NFS_INO_INVALID_ATTR;
1568 		} else if (new_isize > cur_isize) {
1569 			inode->i_size = new_isize;
1570 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
1571 		}
1572 		nfsi->cache_change_attribute = jiffies;
1573 		dprintk("NFS: isize change on server for file %s/%ld\n",
1574 				inode->i_sb->s_id, inode->i_ino);
1575 	}
1576 
1577 	/* Check if the mtime agrees */
1578 	if (!timespec_equal(&inode->i_mtime, &fattr->mtime)) {
1579 		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1580 		dprintk("NFS: mtime change on server for file %s/%ld\n",
1581 				inode->i_sb->s_id, inode->i_ino);
1582 		invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
1583 		nfsi->cache_change_attribute = jiffies;
1584 	}
1585 
1586 	/* If ctime has changed we should definitely clear access+acl caches */
1587 	if (!timespec_equal(&inode->i_ctime, &fattr->ctime)) {
1588 		invalid |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1589 		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1590 		nfsi->cache_change_attribute = jiffies;
1591 	}
1592 	memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
1593 
1594 	if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO) ||
1595 	    inode->i_uid != fattr->uid ||
1596 	    inode->i_gid != fattr->gid)
1597 		invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1598 
1599 	inode->i_mode = fattr->mode;
1600 	inode->i_nlink = fattr->nlink;
1601 	inode->i_uid = fattr->uid;
1602 	inode->i_gid = fattr->gid;
1603 
1604 	if (fattr->valid & (NFS_ATTR_FATTR_V3 | NFS_ATTR_FATTR_V4)) {
1605 		/*
1606 		 * report the blocks in 512byte units
1607 		 */
1608 		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
1609 		inode->i_blksize = inode->i_sb->s_blocksize;
1610  	} else {
1611  		inode->i_blocks = fattr->du.nfs2.blocks;
1612  		inode->i_blksize = fattr->du.nfs2.blocksize;
1613  	}
1614 
1615 	if ((fattr->valid & NFS_ATTR_FATTR_V4)) {
1616 		if (nfsi->change_attr != fattr->change_attr) {
1617 			dprintk("NFS: change_attr change on server for file %s/%ld\n",
1618 					inode->i_sb->s_id, inode->i_ino);
1619 			nfsi->change_attr = fattr->change_attr;
1620 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1621 			nfsi->cache_change_attribute = jiffies;
1622 		} else
1623 			invalid &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA);
1624 	}
1625 
1626 	/* Update attrtimeo value if we're out of the unstable period */
1627 	if (invalid & NFS_INO_INVALID_ATTR) {
1628 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
1629 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
1630 		nfsi->attrtimeo_timestamp = jiffies;
1631 	} else if (time_after(jiffies, nfsi->attrtimeo_timestamp+nfsi->attrtimeo)) {
1632 		if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
1633 			nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
1634 		nfsi->attrtimeo_timestamp = jiffies;
1635 	}
1636 	/* Don't invalidate the data if we were to blame */
1637 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
1638 				|| S_ISLNK(inode->i_mode)))
1639 		invalid &= ~NFS_INO_INVALID_DATA;
1640 	if (data_stable)
1641 		invalid &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME|NFS_INO_REVAL_PAGECACHE);
1642 	if (!nfs_have_delegation(inode, FMODE_READ))
1643 		nfsi->cache_validity |= invalid;
1644 
1645 	return 0;
1646  out_changed:
1647 	/*
1648 	 * Big trouble! The inode has become a different object.
1649 	 */
1650 #ifdef NFS_PARANOIA
1651 	printk(KERN_DEBUG "%s: inode %ld mode changed, %07o to %07o\n",
1652 			__FUNCTION__, inode->i_ino, inode->i_mode, fattr->mode);
1653 #endif
1654  out_err:
1655 	/*
1656 	 * No need to worry about unhashing the dentry, as the
1657 	 * lookup validation will know that the inode is bad.
1658 	 * (But we fall through to invalidate the caches.)
1659 	 */
1660 	nfs_invalidate_inode(inode);
1661 	return -ESTALE;
1662 
1663  out_fileid:
1664 	printk(KERN_ERR "NFS: server %s error: fileid changed\n"
1665 		"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
1666 		NFS_SERVER(inode)->hostname, inode->i_sb->s_id,
1667 		(long long)nfsi->fileid, (long long)fattr->fileid);
1668 	goto out_err;
1669 }
1670 
1671 /*
1672  * File system information
1673  */
1674 
1675 static int nfs_set_super(struct super_block *s, void *data)
1676 {
1677 	s->s_fs_info = data;
1678 	return set_anon_super(s, data);
1679 }
1680 
1681 static int nfs_compare_super(struct super_block *sb, void *data)
1682 {
1683 	struct nfs_server *server = data;
1684 	struct nfs_server *old = NFS_SB(sb);
1685 
1686 	if (old->addr.sin_addr.s_addr != server->addr.sin_addr.s_addr)
1687 		return 0;
1688 	if (old->addr.sin_port != server->addr.sin_port)
1689 		return 0;
1690 	return !nfs_compare_fh(&old->fh, &server->fh);
1691 }
1692 
1693 static struct super_block *nfs_get_sb(struct file_system_type *fs_type,
1694 	int flags, const char *dev_name, void *raw_data)
1695 {
1696 	int error;
1697 	struct nfs_server *server = NULL;
1698 	struct super_block *s;
1699 	struct nfs_fh *root;
1700 	struct nfs_mount_data *data = raw_data;
1701 
1702 	s = ERR_PTR(-EINVAL);
1703 	if (data == NULL) {
1704 		dprintk("%s: missing data argument\n", __FUNCTION__);
1705 		goto out_err;
1706 	}
1707 	if (data->version <= 0 || data->version > NFS_MOUNT_VERSION) {
1708 		dprintk("%s: bad mount version\n", __FUNCTION__);
1709 		goto out_err;
1710 	}
1711 	switch (data->version) {
1712 		case 1:
1713 			data->namlen = 0;
1714 		case 2:
1715 			data->bsize  = 0;
1716 		case 3:
1717 			if (data->flags & NFS_MOUNT_VER3) {
1718 				dprintk("%s: mount structure version %d does not support NFSv3\n",
1719 						__FUNCTION__,
1720 						data->version);
1721 				goto out_err;
1722 			}
1723 			data->root.size = NFS2_FHSIZE;
1724 			memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1725 		case 4:
1726 			if (data->flags & NFS_MOUNT_SECFLAVOUR) {
1727 				dprintk("%s: mount structure version %d does not support strong security\n",
1728 						__FUNCTION__,
1729 						data->version);
1730 				goto out_err;
1731 			}
1732 		case 5:
1733 			memset(data->context, 0, sizeof(data->context));
1734 	}
1735 #ifndef CONFIG_NFS_V3
1736 	/* If NFSv3 is not compiled in, return -EPROTONOSUPPORT */
1737 	s = ERR_PTR(-EPROTONOSUPPORT);
1738 	if (data->flags & NFS_MOUNT_VER3) {
1739 		dprintk("%s: NFSv3 not compiled into kernel\n", __FUNCTION__);
1740 		goto out_err;
1741 	}
1742 #endif /* CONFIG_NFS_V3 */
1743 
1744 	s = ERR_PTR(-ENOMEM);
1745 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
1746 	if (!server)
1747 		goto out_err;
1748 	/* Zero out the NFS state stuff */
1749 	init_nfsv4_state(server);
1750 	server->client = server->client_sys = server->client_acl = ERR_PTR(-EINVAL);
1751 
1752 	root = &server->fh;
1753 	if (data->flags & NFS_MOUNT_VER3)
1754 		root->size = data->root.size;
1755 	else
1756 		root->size = NFS2_FHSIZE;
1757 	s = ERR_PTR(-EINVAL);
1758 	if (root->size > sizeof(root->data)) {
1759 		dprintk("%s: invalid root filehandle\n", __FUNCTION__);
1760 		goto out_err;
1761 	}
1762 	memcpy(root->data, data->root.data, root->size);
1763 
1764 	/* We now require that the mount process passes the remote address */
1765 	memcpy(&server->addr, &data->addr, sizeof(server->addr));
1766 	if (server->addr.sin_addr.s_addr == INADDR_ANY) {
1767 		dprintk("%s: mount program didn't pass remote address!\n",
1768 				__FUNCTION__);
1769 		goto out_err;
1770 	}
1771 
1772 	/* Fire up rpciod if not yet running */
1773 	s = ERR_PTR(rpciod_up());
1774 	if (IS_ERR(s)) {
1775 		dprintk("%s: couldn't start rpciod! Error = %ld\n",
1776 				__FUNCTION__, PTR_ERR(s));
1777 		goto out_err;
1778 	}
1779 
1780 	s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
1781 	if (IS_ERR(s) || s->s_root)
1782 		goto out_rpciod_down;
1783 
1784 	s->s_flags = flags;
1785 
1786 	error = nfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0);
1787 	if (error) {
1788 		up_write(&s->s_umount);
1789 		deactivate_super(s);
1790 		return ERR_PTR(error);
1791 	}
1792 	s->s_flags |= MS_ACTIVE;
1793 	return s;
1794 out_rpciod_down:
1795 	rpciod_down();
1796 out_err:
1797 	kfree(server);
1798 	return s;
1799 }
1800 
1801 static void nfs_kill_super(struct super_block *s)
1802 {
1803 	struct nfs_server *server = NFS_SB(s);
1804 
1805 	kill_anon_super(s);
1806 
1807 	if (!IS_ERR(server->client))
1808 		rpc_shutdown_client(server->client);
1809 	if (!IS_ERR(server->client_sys))
1810 		rpc_shutdown_client(server->client_sys);
1811 	if (!IS_ERR(server->client_acl))
1812 		rpc_shutdown_client(server->client_acl);
1813 
1814 	if (!(server->flags & NFS_MOUNT_NONLM))
1815 		lockd_down();	/* release rpc.lockd */
1816 
1817 	rpciod_down();		/* release rpciod */
1818 
1819 	nfs_free_iostats(server->io_stats);
1820 	kfree(server->hostname);
1821 	kfree(server);
1822 }
1823 
1824 static struct file_system_type nfs_fs_type = {
1825 	.owner		= THIS_MODULE,
1826 	.name		= "nfs",
1827 	.get_sb		= nfs_get_sb,
1828 	.kill_sb	= nfs_kill_super,
1829 	.fs_flags	= FS_ODD_RENAME|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
1830 };
1831 
1832 #ifdef CONFIG_NFS_V4
1833 
1834 static void nfs4_clear_inode(struct inode *);
1835 
1836 
1837 static struct super_operations nfs4_sops = {
1838 	.alloc_inode	= nfs_alloc_inode,
1839 	.destroy_inode	= nfs_destroy_inode,
1840 	.write_inode	= nfs_write_inode,
1841 	.delete_inode	= nfs_delete_inode,
1842 	.statfs		= nfs_statfs,
1843 	.clear_inode	= nfs4_clear_inode,
1844 	.umount_begin	= nfs_umount_begin,
1845 	.show_options	= nfs_show_options,
1846 	.show_stats	= nfs_show_stats,
1847 };
1848 
1849 /*
1850  * Clean out any remaining NFSv4 state that might be left over due
1851  * to open() calls that passed nfs_atomic_lookup, but failed to call
1852  * nfs_open().
1853  */
1854 static void nfs4_clear_inode(struct inode *inode)
1855 {
1856 	struct nfs_inode *nfsi = NFS_I(inode);
1857 
1858 	/* If we are holding a delegation, return it! */
1859 	nfs_inode_return_delegation(inode);
1860 	/* First call standard NFS clear_inode() code */
1861 	nfs_clear_inode(inode);
1862 	/* Now clear out any remaining state */
1863 	while (!list_empty(&nfsi->open_states)) {
1864 		struct nfs4_state *state;
1865 
1866 		state = list_entry(nfsi->open_states.next,
1867 				struct nfs4_state,
1868 				inode_states);
1869 		dprintk("%s(%s/%Ld): found unclaimed NFSv4 state %p\n",
1870 				__FUNCTION__,
1871 				inode->i_sb->s_id,
1872 				(long long)NFS_FILEID(inode),
1873 				state);
1874 		BUG_ON(atomic_read(&state->count) != 1);
1875 		nfs4_close_state(state, state->state);
1876 	}
1877 }
1878 
1879 
1880 static int nfs4_fill_super(struct super_block *sb, struct nfs4_mount_data *data, int silent)
1881 {
1882 	struct nfs_server *server;
1883 	struct nfs4_client *clp = NULL;
1884 	struct rpc_xprt *xprt = NULL;
1885 	struct rpc_clnt *clnt = NULL;
1886 	struct rpc_timeout timeparms;
1887 	rpc_authflavor_t authflavour;
1888 	int err = -EIO;
1889 
1890 	sb->s_blocksize_bits = 0;
1891 	sb->s_blocksize = 0;
1892 	server = NFS_SB(sb);
1893 	if (data->rsize != 0)
1894 		server->rsize = nfs_block_size(data->rsize, NULL);
1895 	if (data->wsize != 0)
1896 		server->wsize = nfs_block_size(data->wsize, NULL);
1897 	server->flags = data->flags & NFS_MOUNT_FLAGMASK;
1898 	server->caps = NFS_CAP_ATOMIC_OPEN;
1899 
1900 	server->acregmin = data->acregmin*HZ;
1901 	server->acregmax = data->acregmax*HZ;
1902 	server->acdirmin = data->acdirmin*HZ;
1903 	server->acdirmax = data->acdirmax*HZ;
1904 
1905 	server->rpc_ops = &nfs_v4_clientops;
1906 
1907 	nfs_init_timeout_values(&timeparms, data->proto, data->timeo, data->retrans);
1908 
1909 	server->retrans_timeo = timeparms.to_initval;
1910 	server->retrans_count = timeparms.to_retries;
1911 
1912 	clp = nfs4_get_client(&server->addr.sin_addr);
1913 	if (!clp) {
1914 		dprintk("%s: failed to create NFS4 client.\n", __FUNCTION__);
1915 		return -EIO;
1916 	}
1917 
1918 	/* Now create transport and client */
1919 	authflavour = RPC_AUTH_UNIX;
1920 	if (data->auth_flavourlen != 0) {
1921 		if (data->auth_flavourlen != 1) {
1922 			dprintk("%s: Invalid number of RPC auth flavours %d.\n",
1923 					__FUNCTION__, data->auth_flavourlen);
1924 			err = -EINVAL;
1925 			goto out_fail;
1926 		}
1927 		if (copy_from_user(&authflavour, data->auth_flavours, sizeof(authflavour))) {
1928 			err = -EFAULT;
1929 			goto out_fail;
1930 		}
1931 	}
1932 
1933 	down_write(&clp->cl_sem);
1934 	if (IS_ERR(clp->cl_rpcclient)) {
1935 		xprt = xprt_create_proto(data->proto, &server->addr, &timeparms);
1936 		if (IS_ERR(xprt)) {
1937 			up_write(&clp->cl_sem);
1938 			err = PTR_ERR(xprt);
1939 			dprintk("%s: cannot create RPC transport. Error = %d\n",
1940 					__FUNCTION__, err);
1941 			goto out_fail;
1942 		}
1943 		clnt = rpc_create_client(xprt, server->hostname, &nfs_program,
1944 				server->rpc_ops->version, authflavour);
1945 		if (IS_ERR(clnt)) {
1946 			up_write(&clp->cl_sem);
1947 			err = PTR_ERR(clnt);
1948 			dprintk("%s: cannot create RPC client. Error = %d\n",
1949 					__FUNCTION__, err);
1950 			goto out_fail;
1951 		}
1952 		clnt->cl_intr     = 1;
1953 		clnt->cl_softrtry = 1;
1954 		clp->cl_rpcclient = clnt;
1955 		memcpy(clp->cl_ipaddr, server->ip_addr, sizeof(clp->cl_ipaddr));
1956 		nfs_idmap_new(clp);
1957 	}
1958 	list_add_tail(&server->nfs4_siblings, &clp->cl_superblocks);
1959 	clnt = rpc_clone_client(clp->cl_rpcclient);
1960 	if (!IS_ERR(clnt))
1961 			server->nfs4_state = clp;
1962 	up_write(&clp->cl_sem);
1963 	clp = NULL;
1964 
1965 	if (IS_ERR(clnt)) {
1966 		err = PTR_ERR(clnt);
1967 		dprintk("%s: cannot create RPC client. Error = %d\n",
1968 				__FUNCTION__, err);
1969 		return err;
1970 	}
1971 
1972 	server->client    = clnt;
1973 
1974 	if (server->nfs4_state->cl_idmap == NULL) {
1975 		dprintk("%s: failed to create idmapper.\n", __FUNCTION__);
1976 		return -ENOMEM;
1977 	}
1978 
1979 	if (clnt->cl_auth->au_flavor != authflavour) {
1980 		struct rpc_auth *auth;
1981 
1982 		auth = rpcauth_create(authflavour, clnt);
1983 		if (IS_ERR(auth)) {
1984 			dprintk("%s: couldn't create credcache!\n", __FUNCTION__);
1985 			return PTR_ERR(auth);
1986 		}
1987 	}
1988 
1989 	sb->s_time_gran = 1;
1990 
1991 	sb->s_op = &nfs4_sops;
1992 	err = nfs_sb_init(sb, authflavour);
1993 	if (err == 0)
1994 		return 0;
1995 out_fail:
1996 	if (clp)
1997 		nfs4_put_client(clp);
1998 	return err;
1999 }
2000 
2001 static int nfs4_compare_super(struct super_block *sb, void *data)
2002 {
2003 	struct nfs_server *server = data;
2004 	struct nfs_server *old = NFS_SB(sb);
2005 
2006 	if (strcmp(server->hostname, old->hostname) != 0)
2007 		return 0;
2008 	if (strcmp(server->mnt_path, old->mnt_path) != 0)
2009 		return 0;
2010 	return 1;
2011 }
2012 
2013 static void *
2014 nfs_copy_user_string(char *dst, struct nfs_string *src, int maxlen)
2015 {
2016 	void *p = NULL;
2017 
2018 	if (!src->len)
2019 		return ERR_PTR(-EINVAL);
2020 	if (src->len < maxlen)
2021 		maxlen = src->len;
2022 	if (dst == NULL) {
2023 		p = dst = kmalloc(maxlen + 1, GFP_KERNEL);
2024 		if (p == NULL)
2025 			return ERR_PTR(-ENOMEM);
2026 	}
2027 	if (copy_from_user(dst, src->data, maxlen)) {
2028 		kfree(p);
2029 		return ERR_PTR(-EFAULT);
2030 	}
2031 	dst[maxlen] = '\0';
2032 	return dst;
2033 }
2034 
2035 static struct super_block *nfs4_get_sb(struct file_system_type *fs_type,
2036 	int flags, const char *dev_name, void *raw_data)
2037 {
2038 	int error;
2039 	struct nfs_server *server;
2040 	struct super_block *s;
2041 	struct nfs4_mount_data *data = raw_data;
2042 	void *p;
2043 
2044 	if (data == NULL) {
2045 		dprintk("%s: missing data argument\n", __FUNCTION__);
2046 		return ERR_PTR(-EINVAL);
2047 	}
2048 	if (data->version <= 0 || data->version > NFS4_MOUNT_VERSION) {
2049 		dprintk("%s: bad mount version\n", __FUNCTION__);
2050 		return ERR_PTR(-EINVAL);
2051 	}
2052 
2053 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
2054 	if (!server)
2055 		return ERR_PTR(-ENOMEM);
2056 	/* Zero out the NFS state stuff */
2057 	init_nfsv4_state(server);
2058 	server->client = server->client_sys = server->client_acl = ERR_PTR(-EINVAL);
2059 
2060 	p = nfs_copy_user_string(NULL, &data->hostname, 256);
2061 	if (IS_ERR(p))
2062 		goto out_err;
2063 	server->hostname = p;
2064 
2065 	p = nfs_copy_user_string(NULL, &data->mnt_path, 1024);
2066 	if (IS_ERR(p))
2067 		goto out_err;
2068 	server->mnt_path = p;
2069 
2070 	p = nfs_copy_user_string(server->ip_addr, &data->client_addr,
2071 			sizeof(server->ip_addr) - 1);
2072 	if (IS_ERR(p))
2073 		goto out_err;
2074 
2075 	/* We now require that the mount process passes the remote address */
2076 	if (data->host_addrlen != sizeof(server->addr)) {
2077 		s = ERR_PTR(-EINVAL);
2078 		goto out_free;
2079 	}
2080 	if (copy_from_user(&server->addr, data->host_addr, sizeof(server->addr))) {
2081 		s = ERR_PTR(-EFAULT);
2082 		goto out_free;
2083 	}
2084 	if (server->addr.sin_family != AF_INET ||
2085 	    server->addr.sin_addr.s_addr == INADDR_ANY) {
2086 		dprintk("%s: mount program didn't pass remote IP address!\n",
2087 				__FUNCTION__);
2088 		s = ERR_PTR(-EINVAL);
2089 		goto out_free;
2090 	}
2091 
2092 	/* Fire up rpciod if not yet running */
2093 	s = ERR_PTR(rpciod_up());
2094 	if (IS_ERR(s)) {
2095 		dprintk("%s: couldn't start rpciod! Error = %ld\n",
2096 				__FUNCTION__, PTR_ERR(s));
2097 		goto out_free;
2098 	}
2099 
2100 	s = sget(fs_type, nfs4_compare_super, nfs_set_super, server);
2101 
2102 	if (IS_ERR(s) || s->s_root)
2103 		goto out_free;
2104 
2105 	s->s_flags = flags;
2106 
2107 	error = nfs4_fill_super(s, data, flags & MS_SILENT ? 1 : 0);
2108 	if (error) {
2109 		up_write(&s->s_umount);
2110 		deactivate_super(s);
2111 		return ERR_PTR(error);
2112 	}
2113 	s->s_flags |= MS_ACTIVE;
2114 	return s;
2115 out_err:
2116 	s = (struct super_block *)p;
2117 out_free:
2118 	kfree(server->mnt_path);
2119 	kfree(server->hostname);
2120 	kfree(server);
2121 	return s;
2122 }
2123 
2124 static void nfs4_kill_super(struct super_block *sb)
2125 {
2126 	struct nfs_server *server = NFS_SB(sb);
2127 
2128 	nfs_return_all_delegations(sb);
2129 	kill_anon_super(sb);
2130 
2131 	nfs4_renewd_prepare_shutdown(server);
2132 
2133 	if (server->client != NULL && !IS_ERR(server->client))
2134 		rpc_shutdown_client(server->client);
2135 
2136 	destroy_nfsv4_state(server);
2137 
2138 	rpciod_down();
2139 
2140 	nfs_free_iostats(server->io_stats);
2141 	kfree(server->hostname);
2142 	kfree(server);
2143 }
2144 
2145 static struct file_system_type nfs4_fs_type = {
2146 	.owner		= THIS_MODULE,
2147 	.name		= "nfs4",
2148 	.get_sb		= nfs4_get_sb,
2149 	.kill_sb	= nfs4_kill_super,
2150 	.fs_flags	= FS_ODD_RENAME|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
2151 };
2152 
2153 static const int nfs_set_port_min = 0;
2154 static const int nfs_set_port_max = 65535;
2155 static int param_set_port(const char *val, struct kernel_param *kp)
2156 {
2157 	char *endp;
2158 	int num = simple_strtol(val, &endp, 0);
2159 	if (endp == val || *endp || num < nfs_set_port_min || num > nfs_set_port_max)
2160 		return -EINVAL;
2161 	*((int *)kp->arg) = num;
2162 	return 0;
2163 }
2164 
2165 module_param_call(callback_tcpport, param_set_port, param_get_int,
2166 		 &nfs_callback_set_tcpport, 0644);
2167 
2168 static int param_set_idmap_timeout(const char *val, struct kernel_param *kp)
2169 {
2170 	char *endp;
2171 	int num = simple_strtol(val, &endp, 0);
2172 	int jif = num * HZ;
2173 	if (endp == val || *endp || num < 0 || jif < num)
2174 		return -EINVAL;
2175 	*((int *)kp->arg) = jif;
2176 	return 0;
2177 }
2178 
2179 module_param_call(idmap_cache_timeout, param_set_idmap_timeout, param_get_int,
2180 		 &nfs_idmap_cache_timeout, 0644);
2181 
2182 #define nfs4_init_once(nfsi) \
2183 	do { \
2184 		INIT_LIST_HEAD(&(nfsi)->open_states); \
2185 		nfsi->delegation = NULL; \
2186 		nfsi->delegation_state = 0; \
2187 		init_rwsem(&nfsi->rwsem); \
2188 	} while(0)
2189 
2190 static inline int register_nfs4fs(void)
2191 {
2192 	int ret;
2193 
2194 	ret = nfs_register_sysctl();
2195 	if (ret != 0)
2196 		return ret;
2197 	ret = register_filesystem(&nfs4_fs_type);
2198 	if (ret != 0)
2199 		nfs_unregister_sysctl();
2200 	return ret;
2201 }
2202 
2203 static inline void unregister_nfs4fs(void)
2204 {
2205 	unregister_filesystem(&nfs4_fs_type);
2206 	nfs_unregister_sysctl();
2207 }
2208 #else
2209 #define nfs4_init_once(nfsi) \
2210 	do { } while (0)
2211 #define register_nfs4fs() (0)
2212 #define unregister_nfs4fs()
2213 #endif
2214 
2215 extern int nfs_init_nfspagecache(void);
2216 extern void nfs_destroy_nfspagecache(void);
2217 extern int nfs_init_readpagecache(void);
2218 extern void nfs_destroy_readpagecache(void);
2219 extern int nfs_init_writepagecache(void);
2220 extern void nfs_destroy_writepagecache(void);
2221 #ifdef CONFIG_NFS_DIRECTIO
2222 extern int nfs_init_directcache(void);
2223 extern void nfs_destroy_directcache(void);
2224 #endif
2225 
2226 static kmem_cache_t * nfs_inode_cachep;
2227 
2228 static struct inode *nfs_alloc_inode(struct super_block *sb)
2229 {
2230 	struct nfs_inode *nfsi;
2231 	nfsi = (struct nfs_inode *)kmem_cache_alloc(nfs_inode_cachep, SLAB_KERNEL);
2232 	if (!nfsi)
2233 		return NULL;
2234 	nfsi->flags = 0UL;
2235 	nfsi->cache_validity = 0UL;
2236 	nfsi->cache_change_attribute = jiffies;
2237 #ifdef CONFIG_NFS_V3_ACL
2238 	nfsi->acl_access = ERR_PTR(-EAGAIN);
2239 	nfsi->acl_default = ERR_PTR(-EAGAIN);
2240 #endif
2241 #ifdef CONFIG_NFS_V4
2242 	nfsi->nfs4_acl = NULL;
2243 #endif /* CONFIG_NFS_V4 */
2244 	return &nfsi->vfs_inode;
2245 }
2246 
2247 static void nfs_destroy_inode(struct inode *inode)
2248 {
2249 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
2250 }
2251 
2252 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
2253 {
2254 	struct nfs_inode *nfsi = (struct nfs_inode *) foo;
2255 
2256 	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
2257 	    SLAB_CTOR_CONSTRUCTOR) {
2258 		inode_init_once(&nfsi->vfs_inode);
2259 		spin_lock_init(&nfsi->req_lock);
2260 		INIT_LIST_HEAD(&nfsi->dirty);
2261 		INIT_LIST_HEAD(&nfsi->commit);
2262 		INIT_LIST_HEAD(&nfsi->open_files);
2263 		INIT_RADIX_TREE(&nfsi->nfs_page_tree, GFP_ATOMIC);
2264 		atomic_set(&nfsi->data_updates, 0);
2265 		nfsi->ndirty = 0;
2266 		nfsi->ncommit = 0;
2267 		nfsi->npages = 0;
2268 		nfs4_init_once(nfsi);
2269 	}
2270 }
2271 
2272 static int nfs_init_inodecache(void)
2273 {
2274 	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
2275 					     sizeof(struct nfs_inode),
2276 					     0, (SLAB_RECLAIM_ACCOUNT|
2277 						SLAB_MEM_SPREAD),
2278 					     init_once, NULL);
2279 	if (nfs_inode_cachep == NULL)
2280 		return -ENOMEM;
2281 
2282 	return 0;
2283 }
2284 
2285 static void nfs_destroy_inodecache(void)
2286 {
2287 	if (kmem_cache_destroy(nfs_inode_cachep))
2288 		printk(KERN_INFO "nfs_inode_cache: not all structures were freed\n");
2289 }
2290 
2291 /*
2292  * Initialize NFS
2293  */
2294 static int __init init_nfs_fs(void)
2295 {
2296 	int err;
2297 
2298 	err = nfs_init_nfspagecache();
2299 	if (err)
2300 		goto out4;
2301 
2302 	err = nfs_init_inodecache();
2303 	if (err)
2304 		goto out3;
2305 
2306 	err = nfs_init_readpagecache();
2307 	if (err)
2308 		goto out2;
2309 
2310 	err = nfs_init_writepagecache();
2311 	if (err)
2312 		goto out1;
2313 
2314 #ifdef CONFIG_NFS_DIRECTIO
2315 	err = nfs_init_directcache();
2316 	if (err)
2317 		goto out0;
2318 #endif
2319 
2320 #ifdef CONFIG_PROC_FS
2321 	rpc_proc_register(&nfs_rpcstat);
2322 #endif
2323         err = register_filesystem(&nfs_fs_type);
2324 	if (err)
2325 		goto out;
2326 	if ((err = register_nfs4fs()) != 0)
2327 		goto out;
2328 	return 0;
2329 out:
2330 #ifdef CONFIG_PROC_FS
2331 	rpc_proc_unregister("nfs");
2332 #endif
2333 #ifdef CONFIG_NFS_DIRECTIO
2334 	nfs_destroy_directcache();
2335 out0:
2336 #endif
2337 	nfs_destroy_writepagecache();
2338 out1:
2339 	nfs_destroy_readpagecache();
2340 out2:
2341 	nfs_destroy_inodecache();
2342 out3:
2343 	nfs_destroy_nfspagecache();
2344 out4:
2345 	return err;
2346 }
2347 
2348 static void __exit exit_nfs_fs(void)
2349 {
2350 #ifdef CONFIG_NFS_DIRECTIO
2351 	nfs_destroy_directcache();
2352 #endif
2353 	nfs_destroy_writepagecache();
2354 	nfs_destroy_readpagecache();
2355 	nfs_destroy_inodecache();
2356 	nfs_destroy_nfspagecache();
2357 #ifdef CONFIG_PROC_FS
2358 	rpc_proc_unregister("nfs");
2359 #endif
2360 	unregister_filesystem(&nfs_fs_type);
2361 	unregister_nfs4fs();
2362 }
2363 
2364 /* Not quite true; I just maintain it */
2365 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
2366 MODULE_LICENSE("GPL");
2367 
2368 module_init(init_nfs_fs)
2369 module_exit(exit_nfs_fs)
2370