xref: /linux/fs/nfs/inode.c (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
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@lxorguk.ukuu.org.uk>, while hacking some
9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
10  *
11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
12  *  J.S.Peatfield@damtp.cam.ac.uk
13  *
14  */
15 
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/sched.h>
19 #include <linux/time.h>
20 #include <linux/kernel.h>
21 #include <linux/mm.h>
22 #include <linux/string.h>
23 #include <linux/stat.h>
24 #include <linux/errno.h>
25 #include <linux/unistd.h>
26 #include <linux/sunrpc/clnt.h>
27 #include <linux/sunrpc/stats.h>
28 #include <linux/sunrpc/metrics.h>
29 #include <linux/nfs_fs.h>
30 #include <linux/nfs_mount.h>
31 #include <linux/nfs4_mount.h>
32 #include <linux/lockd/bind.h>
33 #include <linux/seq_file.h>
34 #include <linux/mount.h>
35 #include <linux/nfs_idmap.h>
36 #include <linux/vfs.h>
37 #include <linux/inet.h>
38 #include <linux/nfs_xdr.h>
39 #include <linux/slab.h>
40 #include <linux/compat.h>
41 #include <linux/freezer.h>
42 #include <linux/crc32.h>
43 
44 #include <asm/uaccess.h>
45 
46 #include "nfs4_fs.h"
47 #include "callback.h"
48 #include "delegation.h"
49 #include "iostat.h"
50 #include "internal.h"
51 #include "fscache.h"
52 #include "dns_resolve.h"
53 #include "pnfs.h"
54 #include "netns.h"
55 
56 #define NFSDBG_FACILITY		NFSDBG_VFS
57 
58 #define NFS_64_BIT_INODE_NUMBERS_ENABLED	1
59 
60 /* Default is to see 64-bit inode numbers */
61 static bool enable_ino64 = NFS_64_BIT_INODE_NUMBERS_ENABLED;
62 
63 static void nfs_invalidate_inode(struct inode *);
64 static int nfs_update_inode(struct inode *, struct nfs_fattr *);
65 
66 static struct kmem_cache * nfs_inode_cachep;
67 
68 static inline unsigned long
69 nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
70 {
71 	return nfs_fileid_to_ino_t(fattr->fileid);
72 }
73 
74 /**
75  * nfs_wait_bit_killable - helper for functions that are sleeping on bit locks
76  * @word: long word containing the bit lock
77  */
78 int nfs_wait_bit_killable(void *word)
79 {
80 	if (fatal_signal_pending(current))
81 		return -ERESTARTSYS;
82 	freezable_schedule();
83 	return 0;
84 }
85 
86 /**
87  * nfs_compat_user_ino64 - returns the user-visible inode number
88  * @fileid: 64-bit fileid
89  *
90  * This function returns a 32-bit inode number if the boot parameter
91  * nfs.enable_ino64 is zero.
92  */
93 u64 nfs_compat_user_ino64(u64 fileid)
94 {
95 #ifdef CONFIG_COMPAT
96 	compat_ulong_t ino;
97 #else
98 	unsigned long ino;
99 #endif
100 
101 	if (enable_ino64)
102 		return fileid;
103 	ino = fileid;
104 	if (sizeof(ino) < sizeof(fileid))
105 		ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
106 	return ino;
107 }
108 
109 static void nfs_clear_inode(struct inode *inode)
110 {
111 	/*
112 	 * The following should never happen...
113 	 */
114 	BUG_ON(nfs_have_writebacks(inode));
115 	BUG_ON(!list_empty(&NFS_I(inode)->open_files));
116 	nfs_zap_acl_cache(inode);
117 	nfs_access_zap_cache(inode);
118 	nfs_fscache_release_inode_cookie(inode);
119 }
120 
121 void nfs_evict_inode(struct inode *inode)
122 {
123 	truncate_inode_pages(&inode->i_data, 0);
124 	clear_inode(inode);
125 	nfs_clear_inode(inode);
126 }
127 
128 /**
129  * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
130  */
131 int nfs_sync_mapping(struct address_space *mapping)
132 {
133 	int ret = 0;
134 
135 	if (mapping->nrpages != 0) {
136 		unmap_mapping_range(mapping, 0, 0, 0);
137 		ret = nfs_wb_all(mapping->host);
138 	}
139 	return ret;
140 }
141 
142 /*
143  * Invalidate the local caches
144  */
145 static void nfs_zap_caches_locked(struct inode *inode)
146 {
147 	struct nfs_inode *nfsi = NFS_I(inode);
148 	int mode = inode->i_mode;
149 
150 	nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
151 
152 	nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
153 	nfsi->attrtimeo_timestamp = jiffies;
154 
155 	memset(NFS_COOKIEVERF(inode), 0, sizeof(NFS_COOKIEVERF(inode)));
156 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))
157 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
158 	else
159 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
160 }
161 
162 void nfs_zap_caches(struct inode *inode)
163 {
164 	spin_lock(&inode->i_lock);
165 	nfs_zap_caches_locked(inode);
166 	spin_unlock(&inode->i_lock);
167 }
168 
169 void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
170 {
171 	if (mapping->nrpages != 0) {
172 		spin_lock(&inode->i_lock);
173 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
174 		spin_unlock(&inode->i_lock);
175 	}
176 }
177 
178 void nfs_zap_acl_cache(struct inode *inode)
179 {
180 	void (*clear_acl_cache)(struct inode *);
181 
182 	clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
183 	if (clear_acl_cache != NULL)
184 		clear_acl_cache(inode);
185 	spin_lock(&inode->i_lock);
186 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
187 	spin_unlock(&inode->i_lock);
188 }
189 
190 void nfs_invalidate_atime(struct inode *inode)
191 {
192 	spin_lock(&inode->i_lock);
193 	NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME;
194 	spin_unlock(&inode->i_lock);
195 }
196 
197 /*
198  * Invalidate, but do not unhash, the inode.
199  * NB: must be called with inode->i_lock held!
200  */
201 static void nfs_invalidate_inode(struct inode *inode)
202 {
203 	set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
204 	nfs_zap_caches_locked(inode);
205 }
206 
207 struct nfs_find_desc {
208 	struct nfs_fh		*fh;
209 	struct nfs_fattr	*fattr;
210 };
211 
212 /*
213  * In NFSv3 we can have 64bit inode numbers. In order to support
214  * this, and re-exported directories (also seen in NFSv2)
215  * we are forced to allow 2 different inodes to have the same
216  * i_ino.
217  */
218 static int
219 nfs_find_actor(struct inode *inode, void *opaque)
220 {
221 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
222 	struct nfs_fh		*fh = desc->fh;
223 	struct nfs_fattr	*fattr = desc->fattr;
224 
225 	if (NFS_FILEID(inode) != fattr->fileid)
226 		return 0;
227 	if (nfs_compare_fh(NFS_FH(inode), fh))
228 		return 0;
229 	if (is_bad_inode(inode) || NFS_STALE(inode))
230 		return 0;
231 	return 1;
232 }
233 
234 static int
235 nfs_init_locked(struct inode *inode, void *opaque)
236 {
237 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
238 	struct nfs_fattr	*fattr = desc->fattr;
239 
240 	set_nfs_fileid(inode, fattr->fileid);
241 	nfs_copy_fh(NFS_FH(inode), desc->fh);
242 	return 0;
243 }
244 
245 /*
246  * This is our front-end to iget that looks up inodes by file handle
247  * instead of inode number.
248  */
249 struct inode *
250 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
251 {
252 	struct nfs_find_desc desc = {
253 		.fh	= fh,
254 		.fattr	= fattr
255 	};
256 	struct inode *inode = ERR_PTR(-ENOENT);
257 	unsigned long hash;
258 
259 	nfs_attr_check_mountpoint(sb, fattr);
260 
261 	if (((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0) &&
262 	    !nfs_attr_use_mounted_on_fileid(fattr))
263 		goto out_no_inode;
264 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
265 		goto out_no_inode;
266 
267 	hash = nfs_fattr_to_ino_t(fattr);
268 
269 	inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
270 	if (inode == NULL) {
271 		inode = ERR_PTR(-ENOMEM);
272 		goto out_no_inode;
273 	}
274 
275 	if (inode->i_state & I_NEW) {
276 		struct nfs_inode *nfsi = NFS_I(inode);
277 		unsigned long now = jiffies;
278 
279 		/* We set i_ino for the few things that still rely on it,
280 		 * such as stat(2) */
281 		inode->i_ino = hash;
282 
283 		/* We can't support update_atime(), since the server will reset it */
284 		inode->i_flags |= S_NOATIME|S_NOCMTIME;
285 		inode->i_mode = fattr->mode;
286 		if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
287 				&& nfs_server_capable(inode, NFS_CAP_MODE))
288 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
289 		/* Why so? Because we want revalidate for devices/FIFOs, and
290 		 * that's precisely what we have in nfs_file_inode_operations.
291 		 */
292 		inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
293 		if (S_ISREG(inode->i_mode)) {
294 			inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
295 			inode->i_data.a_ops = &nfs_file_aops;
296 			inode->i_data.backing_dev_info = &NFS_SB(sb)->backing_dev_info;
297 		} else if (S_ISDIR(inode->i_mode)) {
298 			inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
299 			inode->i_fop = &nfs_dir_operations;
300 			inode->i_data.a_ops = &nfs_dir_aops;
301 			/* Deal with crossing mountpoints */
302 			if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
303 					fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
304 				if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
305 					inode->i_op = &nfs_referral_inode_operations;
306 				else
307 					inode->i_op = &nfs_mountpoint_inode_operations;
308 				inode->i_fop = NULL;
309 				inode->i_flags |= S_AUTOMOUNT;
310 			}
311 		} else if (S_ISLNK(inode->i_mode))
312 			inode->i_op = &nfs_symlink_inode_operations;
313 		else
314 			init_special_inode(inode, inode->i_mode, fattr->rdev);
315 
316 		memset(&inode->i_atime, 0, sizeof(inode->i_atime));
317 		memset(&inode->i_mtime, 0, sizeof(inode->i_mtime));
318 		memset(&inode->i_ctime, 0, sizeof(inode->i_ctime));
319 		inode->i_version = 0;
320 		inode->i_size = 0;
321 		clear_nlink(inode);
322 		inode->i_uid = -2;
323 		inode->i_gid = -2;
324 		inode->i_blocks = 0;
325 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
326 		nfsi->write_io = 0;
327 		nfsi->read_io = 0;
328 
329 		nfsi->read_cache_jiffies = fattr->time_start;
330 		nfsi->attr_gencount = fattr->gencount;
331 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
332 			inode->i_atime = fattr->atime;
333 		else if (nfs_server_capable(inode, NFS_CAP_ATIME))
334 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
335 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
336 			inode->i_mtime = fattr->mtime;
337 		else if (nfs_server_capable(inode, NFS_CAP_MTIME))
338 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
339 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
340 			inode->i_ctime = fattr->ctime;
341 		else if (nfs_server_capable(inode, NFS_CAP_CTIME))
342 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
343 		if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
344 			inode->i_version = fattr->change_attr;
345 		else if (nfs_server_capable(inode, NFS_CAP_CHANGE_ATTR))
346 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
347 		if (fattr->valid & NFS_ATTR_FATTR_SIZE)
348 			inode->i_size = nfs_size_to_loff_t(fattr->size);
349 		else
350 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
351 				| NFS_INO_REVAL_PAGECACHE;
352 		if (fattr->valid & NFS_ATTR_FATTR_NLINK)
353 			set_nlink(inode, fattr->nlink);
354 		else if (nfs_server_capable(inode, NFS_CAP_NLINK))
355 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
356 		if (fattr->valid & NFS_ATTR_FATTR_OWNER)
357 			inode->i_uid = fattr->uid;
358 		else if (nfs_server_capable(inode, NFS_CAP_OWNER))
359 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
360 		if (fattr->valid & NFS_ATTR_FATTR_GROUP)
361 			inode->i_gid = fattr->gid;
362 		else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
363 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
364 		if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
365 			inode->i_blocks = fattr->du.nfs2.blocks;
366 		if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
367 			/*
368 			 * report the blocks in 512byte units
369 			 */
370 			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
371 		}
372 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
373 		nfsi->attrtimeo_timestamp = now;
374 		nfsi->access_cache = RB_ROOT;
375 
376 		nfs_fscache_init_inode_cookie(inode);
377 
378 		unlock_new_inode(inode);
379 	} else
380 		nfs_refresh_inode(inode, fattr);
381 	dprintk("NFS: nfs_fhget(%s/%Ld fh_crc=0x%08x ct=%d)\n",
382 		inode->i_sb->s_id,
383 		(long long)NFS_FILEID(inode),
384 		nfs_display_fhandle_hash(fh),
385 		atomic_read(&inode->i_count));
386 
387 out:
388 	return inode;
389 
390 out_no_inode:
391 	dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
392 	goto out;
393 }
394 
395 #define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
396 
397 int
398 nfs_setattr(struct dentry *dentry, struct iattr *attr)
399 {
400 	struct inode *inode = dentry->d_inode;
401 	struct nfs_fattr *fattr;
402 	int error = -ENOMEM;
403 
404 	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
405 
406 	/* skip mode change if it's just for clearing setuid/setgid */
407 	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
408 		attr->ia_valid &= ~ATTR_MODE;
409 
410 	if (attr->ia_valid & ATTR_SIZE) {
411 		if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
412 			attr->ia_valid &= ~ATTR_SIZE;
413 	}
414 
415 	/* Optimization: if the end result is no change, don't RPC */
416 	attr->ia_valid &= NFS_VALID_ATTRS;
417 	if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
418 		return 0;
419 
420 	/* Write all dirty data */
421 	if (S_ISREG(inode->i_mode)) {
422 		nfs_inode_dio_wait(inode);
423 		nfs_wb_all(inode);
424 	}
425 
426 	fattr = nfs_alloc_fattr();
427 	if (fattr == NULL)
428 		goto out;
429 	/*
430 	 * Return any delegations if we're going to change ACLs
431 	 */
432 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
433 		nfs_inode_return_delegation(inode);
434 	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
435 	if (error == 0)
436 		nfs_refresh_inode(inode, fattr);
437 	nfs_free_fattr(fattr);
438 out:
439 	return error;
440 }
441 
442 /**
443  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
444  * @inode: inode of the file used
445  * @offset: file offset to start truncating
446  *
447  * This is a copy of the common vmtruncate, but with the locking
448  * corrected to take into account the fact that NFS requires
449  * inode->i_size to be updated under the inode->i_lock.
450  */
451 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
452 {
453 	loff_t oldsize;
454 	int err;
455 
456 	err = inode_newsize_ok(inode, offset);
457 	if (err)
458 		goto out;
459 
460 	spin_lock(&inode->i_lock);
461 	oldsize = inode->i_size;
462 	i_size_write(inode, offset);
463 	spin_unlock(&inode->i_lock);
464 
465 	truncate_pagecache(inode, oldsize, offset);
466 out:
467 	return err;
468 }
469 
470 /**
471  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
472  * @inode: pointer to struct inode
473  * @attr: pointer to struct iattr
474  *
475  * Note: we do this in the *proc.c in order to ensure that
476  *       it works for things like exclusive creates too.
477  */
478 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
479 {
480 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
481 		spin_lock(&inode->i_lock);
482 		if ((attr->ia_valid & ATTR_MODE) != 0) {
483 			int mode = attr->ia_mode & S_IALLUGO;
484 			mode |= inode->i_mode & ~S_IALLUGO;
485 			inode->i_mode = mode;
486 		}
487 		if ((attr->ia_valid & ATTR_UID) != 0)
488 			inode->i_uid = attr->ia_uid;
489 		if ((attr->ia_valid & ATTR_GID) != 0)
490 			inode->i_gid = attr->ia_gid;
491 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
492 		spin_unlock(&inode->i_lock);
493 	}
494 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
495 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
496 		nfs_vmtruncate(inode, attr->ia_size);
497 	}
498 }
499 
500 int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
501 {
502 	struct inode *inode = dentry->d_inode;
503 	int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
504 	int err;
505 
506 	/* Flush out writes to the server in order to update c/mtime.  */
507 	if (S_ISREG(inode->i_mode)) {
508 		nfs_inode_dio_wait(inode);
509 		err = filemap_write_and_wait(inode->i_mapping);
510 		if (err)
511 			goto out;
512 	}
513 
514 	/*
515 	 * We may force a getattr if the user cares about atime.
516 	 *
517 	 * Note that we only have to check the vfsmount flags here:
518 	 *  - NFS always sets S_NOATIME by so checking it would give a
519 	 *    bogus result
520 	 *  - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
521 	 *    no point in checking those.
522 	 */
523  	if ((mnt->mnt_flags & MNT_NOATIME) ||
524  	    ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
525 		need_atime = 0;
526 
527 	if (need_atime)
528 		err = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
529 	else
530 		err = nfs_revalidate_inode(NFS_SERVER(inode), inode);
531 	if (!err) {
532 		generic_fillattr(inode, stat);
533 		stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
534 	}
535 out:
536 	return err;
537 }
538 
539 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
540 {
541 	atomic_set(&l_ctx->count, 1);
542 	l_ctx->lockowner = current->files;
543 	l_ctx->pid = current->tgid;
544 	INIT_LIST_HEAD(&l_ctx->list);
545 }
546 
547 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
548 {
549 	struct nfs_lock_context *pos;
550 
551 	list_for_each_entry(pos, &ctx->lock_context.list, list) {
552 		if (pos->lockowner != current->files)
553 			continue;
554 		if (pos->pid != current->tgid)
555 			continue;
556 		atomic_inc(&pos->count);
557 		return pos;
558 	}
559 	return NULL;
560 }
561 
562 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
563 {
564 	struct nfs_lock_context *res, *new = NULL;
565 	struct inode *inode = ctx->dentry->d_inode;
566 
567 	spin_lock(&inode->i_lock);
568 	res = __nfs_find_lock_context(ctx);
569 	if (res == NULL) {
570 		spin_unlock(&inode->i_lock);
571 		new = kmalloc(sizeof(*new), GFP_KERNEL);
572 		if (new == NULL)
573 			return NULL;
574 		nfs_init_lock_context(new);
575 		spin_lock(&inode->i_lock);
576 		res = __nfs_find_lock_context(ctx);
577 		if (res == NULL) {
578 			list_add_tail(&new->list, &ctx->lock_context.list);
579 			new->open_context = ctx;
580 			res = new;
581 			new = NULL;
582 		}
583 	}
584 	spin_unlock(&inode->i_lock);
585 	kfree(new);
586 	return res;
587 }
588 
589 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
590 {
591 	struct nfs_open_context *ctx = l_ctx->open_context;
592 	struct inode *inode = ctx->dentry->d_inode;
593 
594 	if (!atomic_dec_and_lock(&l_ctx->count, &inode->i_lock))
595 		return;
596 	list_del(&l_ctx->list);
597 	spin_unlock(&inode->i_lock);
598 	kfree(l_ctx);
599 }
600 
601 /**
602  * nfs_close_context - Common close_context() routine NFSv2/v3
603  * @ctx: pointer to context
604  * @is_sync: is this a synchronous close
605  *
606  * always ensure that the attributes are up to date if we're mounted
607  * with close-to-open semantics
608  */
609 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
610 {
611 	struct inode *inode;
612 	struct nfs_server *server;
613 
614 	if (!(ctx->mode & FMODE_WRITE))
615 		return;
616 	if (!is_sync)
617 		return;
618 	inode = ctx->dentry->d_inode;
619 	if (!list_empty(&NFS_I(inode)->open_files))
620 		return;
621 	server = NFS_SERVER(inode);
622 	if (server->flags & NFS_MOUNT_NOCTO)
623 		return;
624 	nfs_revalidate_inode(server, inode);
625 }
626 
627 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode)
628 {
629 	struct nfs_open_context *ctx;
630 	struct rpc_cred *cred = rpc_lookup_cred();
631 	if (IS_ERR(cred))
632 		return ERR_CAST(cred);
633 
634 	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
635 	if (!ctx) {
636 		put_rpccred(cred);
637 		return ERR_PTR(-ENOMEM);
638 	}
639 	nfs_sb_active(dentry->d_sb);
640 	ctx->dentry = dget(dentry);
641 	ctx->cred = cred;
642 	ctx->state = NULL;
643 	ctx->mode = f_mode;
644 	ctx->flags = 0;
645 	ctx->error = 0;
646 	nfs_init_lock_context(&ctx->lock_context);
647 	ctx->lock_context.open_context = ctx;
648 	INIT_LIST_HEAD(&ctx->list);
649 	ctx->mdsthreshold = NULL;
650 	return ctx;
651 }
652 
653 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
654 {
655 	if (ctx != NULL)
656 		atomic_inc(&ctx->lock_context.count);
657 	return ctx;
658 }
659 
660 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
661 {
662 	struct inode *inode = ctx->dentry->d_inode;
663 	struct super_block *sb = ctx->dentry->d_sb;
664 
665 	if (!list_empty(&ctx->list)) {
666 		if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
667 			return;
668 		list_del(&ctx->list);
669 		spin_unlock(&inode->i_lock);
670 	} else if (!atomic_dec_and_test(&ctx->lock_context.count))
671 		return;
672 	if (inode != NULL)
673 		NFS_PROTO(inode)->close_context(ctx, is_sync);
674 	if (ctx->cred != NULL)
675 		put_rpccred(ctx->cred);
676 	dput(ctx->dentry);
677 	nfs_sb_deactive(sb);
678 	kfree(ctx->mdsthreshold);
679 	kfree(ctx);
680 }
681 
682 void put_nfs_open_context(struct nfs_open_context *ctx)
683 {
684 	__put_nfs_open_context(ctx, 0);
685 }
686 
687 /*
688  * Ensure that mmap has a recent RPC credential for use when writing out
689  * shared pages
690  */
691 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
692 {
693 	struct inode *inode = filp->f_path.dentry->d_inode;
694 	struct nfs_inode *nfsi = NFS_I(inode);
695 
696 	filp->private_data = get_nfs_open_context(ctx);
697 	spin_lock(&inode->i_lock);
698 	list_add(&ctx->list, &nfsi->open_files);
699 	spin_unlock(&inode->i_lock);
700 }
701 
702 /*
703  * Given an inode, search for an open context with the desired characteristics
704  */
705 struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode)
706 {
707 	struct nfs_inode *nfsi = NFS_I(inode);
708 	struct nfs_open_context *pos, *ctx = NULL;
709 
710 	spin_lock(&inode->i_lock);
711 	list_for_each_entry(pos, &nfsi->open_files, list) {
712 		if (cred != NULL && pos->cred != cred)
713 			continue;
714 		if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
715 			continue;
716 		ctx = get_nfs_open_context(pos);
717 		break;
718 	}
719 	spin_unlock(&inode->i_lock);
720 	return ctx;
721 }
722 
723 static void nfs_file_clear_open_context(struct file *filp)
724 {
725 	struct inode *inode = filp->f_path.dentry->d_inode;
726 	struct nfs_open_context *ctx = nfs_file_open_context(filp);
727 
728 	if (ctx) {
729 		filp->private_data = NULL;
730 		spin_lock(&inode->i_lock);
731 		list_move_tail(&ctx->list, &NFS_I(inode)->open_files);
732 		spin_unlock(&inode->i_lock);
733 		__put_nfs_open_context(ctx, filp->f_flags & O_DIRECT ? 0 : 1);
734 	}
735 }
736 
737 /*
738  * These allocate and release file read/write context information.
739  */
740 int nfs_open(struct inode *inode, struct file *filp)
741 {
742 	struct nfs_open_context *ctx;
743 
744 	ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
745 	if (IS_ERR(ctx))
746 		return PTR_ERR(ctx);
747 	nfs_file_set_open_context(filp, ctx);
748 	put_nfs_open_context(ctx);
749 	nfs_fscache_set_inode_cookie(inode, filp);
750 	return 0;
751 }
752 
753 int nfs_release(struct inode *inode, struct file *filp)
754 {
755 	nfs_file_clear_open_context(filp);
756 	return 0;
757 }
758 
759 /*
760  * This function is called whenever some part of NFS notices that
761  * the cached attributes have to be refreshed.
762  */
763 int
764 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
765 {
766 	int		 status = -ESTALE;
767 	struct nfs_fattr *fattr = NULL;
768 	struct nfs_inode *nfsi = NFS_I(inode);
769 
770 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Ld)\n",
771 		inode->i_sb->s_id, (long long)NFS_FILEID(inode));
772 
773 	if (is_bad_inode(inode))
774 		goto out;
775 	if (NFS_STALE(inode))
776 		goto out;
777 
778 	status = -ENOMEM;
779 	fattr = nfs_alloc_fattr();
780 	if (fattr == NULL)
781 		goto out;
782 
783 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
784 	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr);
785 	if (status != 0) {
786 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) getattr failed, error=%d\n",
787 			 inode->i_sb->s_id,
788 			 (long long)NFS_FILEID(inode), status);
789 		if (status == -ESTALE) {
790 			nfs_zap_caches(inode);
791 			if (!S_ISDIR(inode->i_mode))
792 				set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
793 		}
794 		goto out;
795 	}
796 
797 	status = nfs_refresh_inode(inode, fattr);
798 	if (status) {
799 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) refresh failed, error=%d\n",
800 			 inode->i_sb->s_id,
801 			 (long long)NFS_FILEID(inode), status);
802 		goto out;
803 	}
804 
805 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
806 		nfs_zap_acl_cache(inode);
807 
808 	dfprintk(PAGECACHE, "NFS: (%s/%Ld) revalidation complete\n",
809 		inode->i_sb->s_id,
810 		(long long)NFS_FILEID(inode));
811 
812  out:
813 	nfs_free_fattr(fattr);
814 	return status;
815 }
816 
817 int nfs_attribute_timeout(struct inode *inode)
818 {
819 	struct nfs_inode *nfsi = NFS_I(inode);
820 
821 	return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
822 }
823 
824 static int nfs_attribute_cache_expired(struct inode *inode)
825 {
826 	if (nfs_have_delegated_attributes(inode))
827 		return 0;
828 	return nfs_attribute_timeout(inode);
829 }
830 
831 /**
832  * nfs_revalidate_inode - Revalidate the inode attributes
833  * @server - pointer to nfs_server struct
834  * @inode - pointer to inode struct
835  *
836  * Updates inode attribute information by retrieving the data from the server.
837  */
838 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
839 {
840 	if (!(NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATTR)
841 			&& !nfs_attribute_cache_expired(inode))
842 		return NFS_STALE(inode) ? -ESTALE : 0;
843 	return __nfs_revalidate_inode(server, inode);
844 }
845 
846 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
847 {
848 	struct nfs_inode *nfsi = NFS_I(inode);
849 
850 	if (mapping->nrpages != 0) {
851 		int ret = invalidate_inode_pages2(mapping);
852 		if (ret < 0)
853 			return ret;
854 	}
855 	spin_lock(&inode->i_lock);
856 	nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
857 	if (S_ISDIR(inode->i_mode))
858 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
859 	spin_unlock(&inode->i_lock);
860 	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
861 	nfs_fscache_reset_inode_cookie(inode);
862 	dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
863 			inode->i_sb->s_id, (long long)NFS_FILEID(inode));
864 	return 0;
865 }
866 
867 static bool nfs_mapping_need_revalidate_inode(struct inode *inode)
868 {
869 	if (nfs_have_delegated_attributes(inode))
870 		return false;
871 	return (NFS_I(inode)->cache_validity & NFS_INO_REVAL_PAGECACHE)
872 		|| nfs_attribute_timeout(inode)
873 		|| NFS_STALE(inode);
874 }
875 
876 /**
877  * nfs_revalidate_mapping - Revalidate the pagecache
878  * @inode - pointer to host inode
879  * @mapping - pointer to mapping
880  */
881 int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
882 {
883 	struct nfs_inode *nfsi = NFS_I(inode);
884 	int ret = 0;
885 
886 	if (nfs_mapping_need_revalidate_inode(inode)) {
887 		ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
888 		if (ret < 0)
889 			goto out;
890 	}
891 	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
892 		ret = nfs_invalidate_mapping(inode, mapping);
893 out:
894 	return ret;
895 }
896 
897 static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
898 {
899 	struct nfs_inode *nfsi = NFS_I(inode);
900 	unsigned long ret = 0;
901 
902 	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
903 			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
904 			&& inode->i_version == fattr->pre_change_attr) {
905 		inode->i_version = fattr->change_attr;
906 		if (S_ISDIR(inode->i_mode))
907 			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
908 		ret |= NFS_INO_INVALID_ATTR;
909 	}
910 	/* If we have atomic WCC data, we may update some attributes */
911 	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
912 			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
913 			&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
914 		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
915 		ret |= NFS_INO_INVALID_ATTR;
916 	}
917 
918 	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
919 			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
920 			&& timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
921 		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
922 		if (S_ISDIR(inode->i_mode))
923 			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
924 		ret |= NFS_INO_INVALID_ATTR;
925 	}
926 	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
927 			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
928 			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
929 			&& nfsi->npages == 0) {
930 		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
931 		ret |= NFS_INO_INVALID_ATTR;
932 	}
933 	return ret;
934 }
935 
936 /**
937  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
938  * @inode - pointer to inode
939  * @fattr - updated attributes
940  *
941  * Verifies the attribute cache. If we have just changed the attributes,
942  * so that fattr carries weak cache consistency data, then it may
943  * also update the ctime/mtime/change_attribute.
944  */
945 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
946 {
947 	struct nfs_inode *nfsi = NFS_I(inode);
948 	loff_t cur_size, new_isize;
949 	unsigned long invalid = 0;
950 
951 
952 	if (nfs_have_delegated_attributes(inode))
953 		return 0;
954 	/* Has the inode gone and changed behind our back? */
955 	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
956 		return -EIO;
957 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
958 		return -EIO;
959 
960 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
961 			inode->i_version != fattr->change_attr)
962 		invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
963 
964 	/* Verify a few of the more important attributes */
965 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec_equal(&inode->i_mtime, &fattr->mtime))
966 		invalid |= NFS_INO_INVALID_ATTR;
967 
968 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
969 		cur_size = i_size_read(inode);
970 		new_isize = nfs_size_to_loff_t(fattr->size);
971 		if (cur_size != new_isize && nfsi->npages == 0)
972 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
973 	}
974 
975 	/* Have any file permissions changed? */
976 	if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
977 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
978 	if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && inode->i_uid != fattr->uid)
979 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
980 	if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && inode->i_gid != fattr->gid)
981 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
982 
983 	/* Has the link count changed? */
984 	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
985 		invalid |= NFS_INO_INVALID_ATTR;
986 
987 	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec_equal(&inode->i_atime, &fattr->atime))
988 		invalid |= NFS_INO_INVALID_ATIME;
989 
990 	if (invalid != 0)
991 		nfsi->cache_validity |= invalid;
992 
993 	nfsi->read_cache_jiffies = fattr->time_start;
994 	return 0;
995 }
996 
997 static int nfs_ctime_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
998 {
999 	if (!(fattr->valid & NFS_ATTR_FATTR_CTIME))
1000 		return 0;
1001 	return timespec_compare(&fattr->ctime, &inode->i_ctime) > 0;
1002 }
1003 
1004 static int nfs_size_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1005 {
1006 	if (!(fattr->valid & NFS_ATTR_FATTR_SIZE))
1007 		return 0;
1008 	return nfs_size_to_loff_t(fattr->size) > i_size_read(inode);
1009 }
1010 
1011 static atomic_long_t nfs_attr_generation_counter;
1012 
1013 static unsigned long nfs_read_attr_generation_counter(void)
1014 {
1015 	return atomic_long_read(&nfs_attr_generation_counter);
1016 }
1017 
1018 unsigned long nfs_inc_attr_generation_counter(void)
1019 {
1020 	return atomic_long_inc_return(&nfs_attr_generation_counter);
1021 }
1022 
1023 void nfs_fattr_init(struct nfs_fattr *fattr)
1024 {
1025 	fattr->valid = 0;
1026 	fattr->time_start = jiffies;
1027 	fattr->gencount = nfs_inc_attr_generation_counter();
1028 	fattr->owner_name = NULL;
1029 	fattr->group_name = NULL;
1030 }
1031 
1032 struct nfs_fattr *nfs_alloc_fattr(void)
1033 {
1034 	struct nfs_fattr *fattr;
1035 
1036 	fattr = kmalloc(sizeof(*fattr), GFP_NOFS);
1037 	if (fattr != NULL)
1038 		nfs_fattr_init(fattr);
1039 	return fattr;
1040 }
1041 
1042 struct nfs_fh *nfs_alloc_fhandle(void)
1043 {
1044 	struct nfs_fh *fh;
1045 
1046 	fh = kmalloc(sizeof(struct nfs_fh), GFP_NOFS);
1047 	if (fh != NULL)
1048 		fh->size = 0;
1049 	return fh;
1050 }
1051 
1052 #ifdef NFS_DEBUG
1053 /*
1054  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1055  *                             in the same way that wireshark does
1056  *
1057  * @fh: file handle
1058  *
1059  * For debugging only.
1060  */
1061 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1062 {
1063 	/* wireshark uses 32-bit AUTODIN crc and does a bitwise
1064 	 * not on the result */
1065 	return ~crc32(0xFFFFFFFF, &fh->data[0], fh->size);
1066 }
1067 
1068 /*
1069  * _nfs_display_fhandle - display an NFS file handle on the console
1070  *
1071  * @fh: file handle to display
1072  * @caption: display caption
1073  *
1074  * For debugging only.
1075  */
1076 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1077 {
1078 	unsigned short i;
1079 
1080 	if (fh == NULL || fh->size == 0) {
1081 		printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1082 		return;
1083 	}
1084 
1085 	printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1086 	       caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1087 	for (i = 0; i < fh->size; i += 16) {
1088 		__be32 *pos = (__be32 *)&fh->data[i];
1089 
1090 		switch ((fh->size - i - 1) >> 2) {
1091 		case 0:
1092 			printk(KERN_DEFAULT " %08x\n",
1093 				be32_to_cpup(pos));
1094 			break;
1095 		case 1:
1096 			printk(KERN_DEFAULT " %08x %08x\n",
1097 				be32_to_cpup(pos), be32_to_cpup(pos + 1));
1098 			break;
1099 		case 2:
1100 			printk(KERN_DEFAULT " %08x %08x %08x\n",
1101 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1102 				be32_to_cpup(pos + 2));
1103 			break;
1104 		default:
1105 			printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1106 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1107 				be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1108 		}
1109 	}
1110 }
1111 #endif
1112 
1113 /**
1114  * nfs_inode_attrs_need_update - check if the inode attributes need updating
1115  * @inode - pointer to inode
1116  * @fattr - attributes
1117  *
1118  * Attempt to divine whether or not an RPC call reply carrying stale
1119  * attributes got scheduled after another call carrying updated ones.
1120  *
1121  * To do so, the function first assumes that a more recent ctime means
1122  * that the attributes in fattr are newer, however it also attempt to
1123  * catch the case where ctime either didn't change, or went backwards
1124  * (if someone reset the clock on the server) by looking at whether
1125  * or not this RPC call was started after the inode was last updated.
1126  * Note also the check for wraparound of 'attr_gencount'
1127  *
1128  * The function returns 'true' if it thinks the attributes in 'fattr' are
1129  * more recent than the ones cached in the inode.
1130  *
1131  */
1132 static int nfs_inode_attrs_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1133 {
1134 	const struct nfs_inode *nfsi = NFS_I(inode);
1135 
1136 	return ((long)fattr->gencount - (long)nfsi->attr_gencount) > 0 ||
1137 		nfs_ctime_need_update(inode, fattr) ||
1138 		nfs_size_need_update(inode, fattr) ||
1139 		((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
1140 }
1141 
1142 static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1143 {
1144 	if (nfs_inode_attrs_need_update(inode, fattr))
1145 		return nfs_update_inode(inode, fattr);
1146 	return nfs_check_inode_attributes(inode, fattr);
1147 }
1148 
1149 /**
1150  * nfs_refresh_inode - try to update the inode attribute cache
1151  * @inode - pointer to inode
1152  * @fattr - updated attributes
1153  *
1154  * Check that an RPC call that returned attributes has not overlapped with
1155  * other recent updates of the inode metadata, then decide whether it is
1156  * safe to do a full update of the inode attributes, or whether just to
1157  * call nfs_check_inode_attributes.
1158  */
1159 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
1160 {
1161 	int status;
1162 
1163 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1164 		return 0;
1165 	spin_lock(&inode->i_lock);
1166 	status = nfs_refresh_inode_locked(inode, fattr);
1167 	spin_unlock(&inode->i_lock);
1168 
1169 	return status;
1170 }
1171 
1172 static int nfs_post_op_update_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1173 {
1174 	struct nfs_inode *nfsi = NFS_I(inode);
1175 
1176 	nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1177 	if (S_ISDIR(inode->i_mode))
1178 		nfsi->cache_validity |= NFS_INO_INVALID_DATA;
1179 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1180 		return 0;
1181 	return nfs_refresh_inode_locked(inode, fattr);
1182 }
1183 
1184 /**
1185  * nfs_post_op_update_inode - try to update the inode attribute cache
1186  * @inode - pointer to inode
1187  * @fattr - updated attributes
1188  *
1189  * After an operation that has changed the inode metadata, mark the
1190  * attribute cache as being invalid, then try to update it.
1191  *
1192  * NB: if the server didn't return any post op attributes, this
1193  * function will force the retrieval of attributes before the next
1194  * NFS request.  Thus it should be used only for operations that
1195  * are expected to change one or more attributes, to avoid
1196  * unnecessary NFS requests and trips through nfs_update_inode().
1197  */
1198 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1199 {
1200 	int status;
1201 
1202 	spin_lock(&inode->i_lock);
1203 	status = nfs_post_op_update_inode_locked(inode, fattr);
1204 	spin_unlock(&inode->i_lock);
1205 	return status;
1206 }
1207 
1208 /**
1209  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
1210  * @inode - pointer to inode
1211  * @fattr - updated attributes
1212  *
1213  * After an operation that has changed the inode metadata, mark the
1214  * attribute cache as being invalid, then try to update it. Fake up
1215  * weak cache consistency data, if none exist.
1216  *
1217  * This function is mainly designed to be used by the ->write_done() functions.
1218  */
1219 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
1220 {
1221 	int status;
1222 
1223 	spin_lock(&inode->i_lock);
1224 	/* Don't do a WCC update if these attributes are already stale */
1225 	if ((fattr->valid & NFS_ATTR_FATTR) == 0 ||
1226 			!nfs_inode_attrs_need_update(inode, fattr)) {
1227 		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
1228 				| NFS_ATTR_FATTR_PRESIZE
1229 				| NFS_ATTR_FATTR_PREMTIME
1230 				| NFS_ATTR_FATTR_PRECTIME);
1231 		goto out_noforce;
1232 	}
1233 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1234 			(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
1235 		fattr->pre_change_attr = inode->i_version;
1236 		fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
1237 	}
1238 	if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
1239 			(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
1240 		memcpy(&fattr->pre_ctime, &inode->i_ctime, sizeof(fattr->pre_ctime));
1241 		fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
1242 	}
1243 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
1244 			(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
1245 		memcpy(&fattr->pre_mtime, &inode->i_mtime, sizeof(fattr->pre_mtime));
1246 		fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
1247 	}
1248 	if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
1249 			(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
1250 		fattr->pre_size = i_size_read(inode);
1251 		fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
1252 	}
1253 out_noforce:
1254 	status = nfs_post_op_update_inode_locked(inode, fattr);
1255 	spin_unlock(&inode->i_lock);
1256 	return status;
1257 }
1258 
1259 /*
1260  * Many nfs protocol calls return the new file attributes after
1261  * an operation.  Here we update the inode to reflect the state
1262  * of the server's inode.
1263  *
1264  * This is a bit tricky because we have to make sure all dirty pages
1265  * have been sent off to the server before calling invalidate_inode_pages.
1266  * To make sure no other process adds more write requests while we try
1267  * our best to flush them, we make them sleep during the attribute refresh.
1268  *
1269  * A very similar scenario holds for the dir cache.
1270  */
1271 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1272 {
1273 	struct nfs_server *server;
1274 	struct nfs_inode *nfsi = NFS_I(inode);
1275 	loff_t cur_isize, new_isize;
1276 	unsigned long invalid = 0;
1277 	unsigned long now = jiffies;
1278 	unsigned long save_cache_validity;
1279 
1280 	dfprintk(VFS, "NFS: %s(%s/%ld fh_crc=0x%08x ct=%d info=0x%x)\n",
1281 			__func__, inode->i_sb->s_id, inode->i_ino,
1282 			nfs_display_fhandle_hash(NFS_FH(inode)),
1283 			atomic_read(&inode->i_count), fattr->valid);
1284 
1285 	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid) {
1286 		printk(KERN_ERR "NFS: server %s error: fileid changed\n"
1287 			"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
1288 			NFS_SERVER(inode)->nfs_client->cl_hostname,
1289 			inode->i_sb->s_id, (long long)nfsi->fileid,
1290 			(long long)fattr->fileid);
1291 		goto out_err;
1292 	}
1293 
1294 	/*
1295 	 * Make sure the inode's type hasn't changed.
1296 	 */
1297 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
1298 		/*
1299 		* Big trouble! The inode has become a different object.
1300 		*/
1301 		printk(KERN_DEBUG "NFS: %s: inode %ld mode changed, %07o to %07o\n",
1302 				__func__, inode->i_ino, inode->i_mode, fattr->mode);
1303 		goto out_err;
1304 	}
1305 
1306 	server = NFS_SERVER(inode);
1307 	/* Update the fsid? */
1308 	if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
1309 			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
1310 			!IS_AUTOMOUNT(inode))
1311 		server->fsid = fattr->fsid;
1312 
1313 	/*
1314 	 * Update the read time so we don't revalidate too often.
1315 	 */
1316 	nfsi->read_cache_jiffies = fattr->time_start;
1317 
1318 	save_cache_validity = nfsi->cache_validity;
1319 	nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
1320 			| NFS_INO_INVALID_ATIME
1321 			| NFS_INO_REVAL_FORCED
1322 			| NFS_INO_REVAL_PAGECACHE);
1323 
1324 	/* Do atomic weak cache consistency updates */
1325 	invalid |= nfs_wcc_update_inode(inode, fattr);
1326 
1327 	/* More cache consistency checks */
1328 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
1329 		if (inode->i_version != fattr->change_attr) {
1330 			dprintk("NFS: change_attr change on server for file %s/%ld\n",
1331 					inode->i_sb->s_id, inode->i_ino);
1332 			invalid |= NFS_INO_INVALID_ATTR
1333 				| NFS_INO_INVALID_DATA
1334 				| NFS_INO_INVALID_ACCESS
1335 				| NFS_INO_INVALID_ACL
1336 				| NFS_INO_REVAL_PAGECACHE;
1337 			if (S_ISDIR(inode->i_mode))
1338 				nfs_force_lookup_revalidate(inode);
1339 			inode->i_version = fattr->change_attr;
1340 		}
1341 	} else if (server->caps & NFS_CAP_CHANGE_ATTR)
1342 		invalid |= save_cache_validity;
1343 
1344 	if (fattr->valid & NFS_ATTR_FATTR_MTIME) {
1345 		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1346 	} else if (server->caps & NFS_CAP_MTIME)
1347 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1348 				| NFS_INO_REVAL_FORCED);
1349 
1350 	if (fattr->valid & NFS_ATTR_FATTR_CTIME) {
1351 		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1352 	} else if (server->caps & NFS_CAP_CTIME)
1353 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1354 				| NFS_INO_REVAL_FORCED);
1355 
1356 	/* Check if our cached file size is stale */
1357 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1358 		new_isize = nfs_size_to_loff_t(fattr->size);
1359 		cur_isize = i_size_read(inode);
1360 		if (new_isize != cur_isize) {
1361 			/* Do we perhaps have any outstanding writes, or has
1362 			 * the file grown beyond our last write? */
1363 			if ((nfsi->npages == 0 && !test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) ||
1364 			     new_isize > cur_isize) {
1365 				i_size_write(inode, new_isize);
1366 				invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
1367 			}
1368 			dprintk("NFS: isize change on server for file %s/%ld "
1369 					"(%Ld to %Ld)\n",
1370 					inode->i_sb->s_id,
1371 					inode->i_ino,
1372 					(long long)cur_isize,
1373 					(long long)new_isize);
1374 		}
1375 	} else
1376 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1377 				| NFS_INO_REVAL_PAGECACHE
1378 				| NFS_INO_REVAL_FORCED);
1379 
1380 
1381 	if (fattr->valid & NFS_ATTR_FATTR_ATIME)
1382 		memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
1383 	else if (server->caps & NFS_CAP_ATIME)
1384 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATIME
1385 				| NFS_INO_REVAL_FORCED);
1386 
1387 	if (fattr->valid & NFS_ATTR_FATTR_MODE) {
1388 		if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
1389 			umode_t newmode = inode->i_mode & S_IFMT;
1390 			newmode |= fattr->mode & S_IALLUGO;
1391 			inode->i_mode = newmode;
1392 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1393 		}
1394 	} else if (server->caps & NFS_CAP_MODE)
1395 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1396 				| NFS_INO_INVALID_ACCESS
1397 				| NFS_INO_INVALID_ACL
1398 				| NFS_INO_REVAL_FORCED);
1399 
1400 	if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
1401 		if (inode->i_uid != fattr->uid) {
1402 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1403 			inode->i_uid = fattr->uid;
1404 		}
1405 	} else if (server->caps & NFS_CAP_OWNER)
1406 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1407 				| NFS_INO_INVALID_ACCESS
1408 				| NFS_INO_INVALID_ACL
1409 				| NFS_INO_REVAL_FORCED);
1410 
1411 	if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
1412 		if (inode->i_gid != fattr->gid) {
1413 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1414 			inode->i_gid = fattr->gid;
1415 		}
1416 	} else if (server->caps & NFS_CAP_OWNER_GROUP)
1417 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1418 				| NFS_INO_INVALID_ACCESS
1419 				| NFS_INO_INVALID_ACL
1420 				| NFS_INO_REVAL_FORCED);
1421 
1422 	if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
1423 		if (inode->i_nlink != fattr->nlink) {
1424 			invalid |= NFS_INO_INVALID_ATTR;
1425 			if (S_ISDIR(inode->i_mode))
1426 				invalid |= NFS_INO_INVALID_DATA;
1427 			set_nlink(inode, fattr->nlink);
1428 		}
1429 	} else if (server->caps & NFS_CAP_NLINK)
1430 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1431 				| NFS_INO_REVAL_FORCED);
1432 
1433 	if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
1434 		/*
1435 		 * report the blocks in 512byte units
1436 		 */
1437 		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
1438  	}
1439 	if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
1440 		inode->i_blocks = fattr->du.nfs2.blocks;
1441 
1442 	/* Update attrtimeo value if we're out of the unstable period */
1443 	if (invalid & NFS_INO_INVALID_ATTR) {
1444 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
1445 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
1446 		nfsi->attrtimeo_timestamp = now;
1447 		nfsi->attr_gencount = nfs_inc_attr_generation_counter();
1448 	} else {
1449 		if (!time_in_range_open(now, nfsi->attrtimeo_timestamp, nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
1450 			if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
1451 				nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
1452 			nfsi->attrtimeo_timestamp = now;
1453 		}
1454 	}
1455 	invalid &= ~NFS_INO_INVALID_ATTR;
1456 	/* Don't invalidate the data if we were to blame */
1457 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
1458 				|| S_ISLNK(inode->i_mode)))
1459 		invalid &= ~NFS_INO_INVALID_DATA;
1460 	if (!nfs_have_delegation(inode, FMODE_READ) ||
1461 			(save_cache_validity & NFS_INO_REVAL_FORCED))
1462 		nfsi->cache_validity |= invalid;
1463 
1464 	return 0;
1465  out_err:
1466 	/*
1467 	 * No need to worry about unhashing the dentry, as the
1468 	 * lookup validation will know that the inode is bad.
1469 	 * (But we fall through to invalidate the caches.)
1470 	 */
1471 	nfs_invalidate_inode(inode);
1472 	return -ESTALE;
1473 }
1474 
1475 
1476 #ifdef CONFIG_NFS_V4
1477 
1478 /*
1479  * Clean out any remaining NFSv4 state that might be left over due
1480  * to open() calls that passed nfs_atomic_lookup, but failed to call
1481  * nfs_open().
1482  */
1483 void nfs4_evict_inode(struct inode *inode)
1484 {
1485 	truncate_inode_pages(&inode->i_data, 0);
1486 	clear_inode(inode);
1487 	pnfs_return_layout(inode);
1488 	pnfs_destroy_layout(NFS_I(inode));
1489 	/* If we are holding a delegation, return it! */
1490 	nfs_inode_return_delegation_noreclaim(inode);
1491 	/* First call standard NFS clear_inode() code */
1492 	nfs_clear_inode(inode);
1493 }
1494 #endif
1495 
1496 struct inode *nfs_alloc_inode(struct super_block *sb)
1497 {
1498 	struct nfs_inode *nfsi;
1499 	nfsi = (struct nfs_inode *)kmem_cache_alloc(nfs_inode_cachep, GFP_KERNEL);
1500 	if (!nfsi)
1501 		return NULL;
1502 	nfsi->flags = 0UL;
1503 	nfsi->cache_validity = 0UL;
1504 #ifdef CONFIG_NFS_V3_ACL
1505 	nfsi->acl_access = ERR_PTR(-EAGAIN);
1506 	nfsi->acl_default = ERR_PTR(-EAGAIN);
1507 #endif
1508 #ifdef CONFIG_NFS_V4
1509 	nfsi->nfs4_acl = NULL;
1510 #endif /* CONFIG_NFS_V4 */
1511 	return &nfsi->vfs_inode;
1512 }
1513 
1514 static void nfs_i_callback(struct rcu_head *head)
1515 {
1516 	struct inode *inode = container_of(head, struct inode, i_rcu);
1517 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
1518 }
1519 
1520 void nfs_destroy_inode(struct inode *inode)
1521 {
1522 	call_rcu(&inode->i_rcu, nfs_i_callback);
1523 }
1524 
1525 static inline void nfs4_init_once(struct nfs_inode *nfsi)
1526 {
1527 #ifdef CONFIG_NFS_V4
1528 	INIT_LIST_HEAD(&nfsi->open_states);
1529 	nfsi->delegation = NULL;
1530 	nfsi->delegation_state = 0;
1531 	init_rwsem(&nfsi->rwsem);
1532 	nfsi->layout = NULL;
1533 #endif
1534 }
1535 
1536 static void init_once(void *foo)
1537 {
1538 	struct nfs_inode *nfsi = (struct nfs_inode *) foo;
1539 
1540 	inode_init_once(&nfsi->vfs_inode);
1541 	INIT_LIST_HEAD(&nfsi->open_files);
1542 	INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
1543 	INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
1544 	INIT_LIST_HEAD(&nfsi->commit_info.list);
1545 	nfsi->npages = 0;
1546 	nfsi->commit_info.ncommit = 0;
1547 	atomic_set(&nfsi->commit_info.rpcs_out, 0);
1548 	atomic_set(&nfsi->silly_count, 1);
1549 	INIT_HLIST_HEAD(&nfsi->silly_list);
1550 	init_waitqueue_head(&nfsi->waitqueue);
1551 	nfs4_init_once(nfsi);
1552 }
1553 
1554 static int __init nfs_init_inodecache(void)
1555 {
1556 	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
1557 					     sizeof(struct nfs_inode),
1558 					     0, (SLAB_RECLAIM_ACCOUNT|
1559 						SLAB_MEM_SPREAD),
1560 					     init_once);
1561 	if (nfs_inode_cachep == NULL)
1562 		return -ENOMEM;
1563 
1564 	return 0;
1565 }
1566 
1567 static void nfs_destroy_inodecache(void)
1568 {
1569 	kmem_cache_destroy(nfs_inode_cachep);
1570 }
1571 
1572 struct workqueue_struct *nfsiod_workqueue;
1573 
1574 /*
1575  * start up the nfsiod workqueue
1576  */
1577 static int nfsiod_start(void)
1578 {
1579 	struct workqueue_struct *wq;
1580 	dprintk("RPC:       creating workqueue nfsiod\n");
1581 	wq = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM, 0);
1582 	if (wq == NULL)
1583 		return -ENOMEM;
1584 	nfsiod_workqueue = wq;
1585 	return 0;
1586 }
1587 
1588 /*
1589  * Destroy the nfsiod workqueue
1590  */
1591 static void nfsiod_stop(void)
1592 {
1593 	struct workqueue_struct *wq;
1594 
1595 	wq = nfsiod_workqueue;
1596 	if (wq == NULL)
1597 		return;
1598 	nfsiod_workqueue = NULL;
1599 	destroy_workqueue(wq);
1600 }
1601 
1602 int nfs_net_id;
1603 EXPORT_SYMBOL_GPL(nfs_net_id);
1604 
1605 static int nfs_net_init(struct net *net)
1606 {
1607 	nfs_clients_init(net);
1608 	return nfs_dns_resolver_cache_init(net);
1609 }
1610 
1611 static void nfs_net_exit(struct net *net)
1612 {
1613 	nfs_dns_resolver_cache_destroy(net);
1614 	nfs_cleanup_cb_ident_idr(net);
1615 }
1616 
1617 static struct pernet_operations nfs_net_ops = {
1618 	.init = nfs_net_init,
1619 	.exit = nfs_net_exit,
1620 	.id   = &nfs_net_id,
1621 	.size = sizeof(struct nfs_net),
1622 };
1623 
1624 /*
1625  * Initialize NFS
1626  */
1627 static int __init init_nfs_fs(void)
1628 {
1629 	int err;
1630 
1631 	err = nfs_idmap_init();
1632 	if (err < 0)
1633 		goto out10;
1634 
1635 	err = nfs_dns_resolver_init();
1636 	if (err < 0)
1637 		goto out9;
1638 
1639 	err = register_pernet_subsys(&nfs_net_ops);
1640 	if (err < 0)
1641 		goto out8;
1642 
1643 	err = nfs_fscache_register();
1644 	if (err < 0)
1645 		goto out7;
1646 
1647 	err = nfsiod_start();
1648 	if (err)
1649 		goto out6;
1650 
1651 	err = nfs_fs_proc_init();
1652 	if (err)
1653 		goto out5;
1654 
1655 	err = nfs_init_nfspagecache();
1656 	if (err)
1657 		goto out4;
1658 
1659 	err = nfs_init_inodecache();
1660 	if (err)
1661 		goto out3;
1662 
1663 	err = nfs_init_readpagecache();
1664 	if (err)
1665 		goto out2;
1666 
1667 	err = nfs_init_writepagecache();
1668 	if (err)
1669 		goto out1;
1670 
1671 	err = nfs_init_directcache();
1672 	if (err)
1673 		goto out0;
1674 
1675 #ifdef CONFIG_PROC_FS
1676 	rpc_proc_register(&init_net, &nfs_rpcstat);
1677 #endif
1678 	if ((err = register_nfs_fs()) != 0)
1679 		goto out;
1680 	return 0;
1681 out:
1682 #ifdef CONFIG_PROC_FS
1683 	rpc_proc_unregister(&init_net, "nfs");
1684 #endif
1685 	nfs_destroy_directcache();
1686 out0:
1687 	nfs_destroy_writepagecache();
1688 out1:
1689 	nfs_destroy_readpagecache();
1690 out2:
1691 	nfs_destroy_inodecache();
1692 out3:
1693 	nfs_destroy_nfspagecache();
1694 out4:
1695 	nfs_fs_proc_exit();
1696 out5:
1697 	nfsiod_stop();
1698 out6:
1699 	nfs_fscache_unregister();
1700 out7:
1701 	unregister_pernet_subsys(&nfs_net_ops);
1702 out8:
1703 	nfs_dns_resolver_destroy();
1704 out9:
1705 	nfs_idmap_quit();
1706 out10:
1707 	return err;
1708 }
1709 
1710 static void __exit exit_nfs_fs(void)
1711 {
1712 	nfs_destroy_directcache();
1713 	nfs_destroy_writepagecache();
1714 	nfs_destroy_readpagecache();
1715 	nfs_destroy_inodecache();
1716 	nfs_destroy_nfspagecache();
1717 	nfs_fscache_unregister();
1718 	unregister_pernet_subsys(&nfs_net_ops);
1719 	nfs_dns_resolver_destroy();
1720 	nfs_idmap_quit();
1721 #ifdef CONFIG_PROC_FS
1722 	rpc_proc_unregister(&init_net, "nfs");
1723 #endif
1724 	unregister_nfs_fs();
1725 	nfs_fs_proc_exit();
1726 	nfsiod_stop();
1727 }
1728 
1729 /* Not quite true; I just maintain it */
1730 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
1731 MODULE_LICENSE("GPL");
1732 module_param(enable_ino64, bool, 0644);
1733 
1734 module_init(init_nfs_fs)
1735 module_exit(exit_nfs_fs)
1736