xref: /openbmc/linux/fs/nfs/inode.c (revision 82df5b73)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/fs/nfs/inode.c
4  *
5  *  Copyright (C) 1992  Rick Sladkey
6  *
7  *  nfs inode and superblock handling functions
8  *
9  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
10  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
11  *
12  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
13  *  J.S.Peatfield@damtp.cam.ac.uk
14  *
15  */
16 
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/sched/signal.h>
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/seq_file.h>
35 #include <linux/mount.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/uaccess.h>
43 #include <linux/iversion.h>
44 
45 #include "nfs4_fs.h"
46 #include "callback.h"
47 #include "delegation.h"
48 #include "iostat.h"
49 #include "internal.h"
50 #include "fscache.h"
51 #include "pnfs.h"
52 #include "nfs.h"
53 #include "netns.h"
54 #include "sysfs.h"
55 
56 #include "nfstrace.h"
57 
58 #define NFSDBG_FACILITY		NFSDBG_VFS
59 
60 #define NFS_64_BIT_INODE_NUMBERS_ENABLED	1
61 
62 /* Default is to see 64-bit inode numbers */
63 static bool enable_ino64 = NFS_64_BIT_INODE_NUMBERS_ENABLED;
64 
65 static int nfs_update_inode(struct inode *, struct nfs_fattr *);
66 
67 static struct kmem_cache * nfs_inode_cachep;
68 
69 static inline unsigned long
70 nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
71 {
72 	return nfs_fileid_to_ino_t(fattr->fileid);
73 }
74 
75 static int nfs_wait_killable(int mode)
76 {
77 	freezable_schedule_unsafe();
78 	if (signal_pending_state(mode, current))
79 		return -ERESTARTSYS;
80 	return 0;
81 }
82 
83 int nfs_wait_bit_killable(struct wait_bit_key *key, int mode)
84 {
85 	return nfs_wait_killable(mode);
86 }
87 EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
88 
89 /**
90  * nfs_compat_user_ino64 - returns the user-visible inode number
91  * @fileid: 64-bit fileid
92  *
93  * This function returns a 32-bit inode number if the boot parameter
94  * nfs.enable_ino64 is zero.
95  */
96 u64 nfs_compat_user_ino64(u64 fileid)
97 {
98 #ifdef CONFIG_COMPAT
99 	compat_ulong_t ino;
100 #else
101 	unsigned long ino;
102 #endif
103 
104 	if (enable_ino64)
105 		return fileid;
106 	ino = fileid;
107 	if (sizeof(ino) < sizeof(fileid))
108 		ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
109 	return ino;
110 }
111 
112 int nfs_drop_inode(struct inode *inode)
113 {
114 	return NFS_STALE(inode) || generic_drop_inode(inode);
115 }
116 EXPORT_SYMBOL_GPL(nfs_drop_inode);
117 
118 void nfs_clear_inode(struct inode *inode)
119 {
120 	/*
121 	 * The following should never happen...
122 	 */
123 	WARN_ON_ONCE(nfs_have_writebacks(inode));
124 	WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files));
125 	nfs_zap_acl_cache(inode);
126 	nfs_access_zap_cache(inode);
127 	nfs_fscache_clear_inode(inode);
128 }
129 EXPORT_SYMBOL_GPL(nfs_clear_inode);
130 
131 void nfs_evict_inode(struct inode *inode)
132 {
133 	truncate_inode_pages_final(&inode->i_data);
134 	clear_inode(inode);
135 	nfs_clear_inode(inode);
136 }
137 
138 int nfs_sync_inode(struct inode *inode)
139 {
140 	inode_dio_wait(inode);
141 	return nfs_wb_all(inode);
142 }
143 EXPORT_SYMBOL_GPL(nfs_sync_inode);
144 
145 /**
146  * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
147  * @mapping: pointer to struct address_space
148  */
149 int nfs_sync_mapping(struct address_space *mapping)
150 {
151 	int ret = 0;
152 
153 	if (mapping->nrpages != 0) {
154 		unmap_mapping_range(mapping, 0, 0, 0);
155 		ret = nfs_wb_all(mapping->host);
156 	}
157 	return ret;
158 }
159 
160 static int nfs_attribute_timeout(struct inode *inode)
161 {
162 	struct nfs_inode *nfsi = NFS_I(inode);
163 
164 	return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
165 }
166 
167 static bool nfs_check_cache_invalid_delegated(struct inode *inode, unsigned long flags)
168 {
169 	unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
170 
171 	/* Special case for the pagecache or access cache */
172 	if (flags == NFS_INO_REVAL_PAGECACHE &&
173 	    !(cache_validity & NFS_INO_REVAL_FORCED))
174 		return false;
175 	return (cache_validity & flags) != 0;
176 }
177 
178 static bool nfs_check_cache_invalid_not_delegated(struct inode *inode, unsigned long flags)
179 {
180 	unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
181 
182 	if ((cache_validity & flags) != 0)
183 		return true;
184 	if (nfs_attribute_timeout(inode))
185 		return true;
186 	return false;
187 }
188 
189 bool nfs_check_cache_invalid(struct inode *inode, unsigned long flags)
190 {
191 	if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
192 		return nfs_check_cache_invalid_delegated(inode, flags);
193 
194 	return nfs_check_cache_invalid_not_delegated(inode, flags);
195 }
196 
197 static void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
198 {
199 	struct nfs_inode *nfsi = NFS_I(inode);
200 	bool have_delegation = NFS_PROTO(inode)->have_delegation(inode, FMODE_READ);
201 
202 	if (have_delegation) {
203 		if (!(flags & NFS_INO_REVAL_FORCED))
204 			flags &= ~NFS_INO_INVALID_OTHER;
205 		flags &= ~(NFS_INO_INVALID_CHANGE
206 				| NFS_INO_INVALID_SIZE
207 				| NFS_INO_REVAL_PAGECACHE);
208 	}
209 
210 	if (inode->i_mapping->nrpages == 0)
211 		flags &= ~(NFS_INO_INVALID_DATA|NFS_INO_DATA_INVAL_DEFER);
212 	nfsi->cache_validity |= flags;
213 	if (flags & NFS_INO_INVALID_DATA)
214 		nfs_fscache_invalidate(inode);
215 }
216 
217 /*
218  * Invalidate the local caches
219  */
220 static void nfs_zap_caches_locked(struct inode *inode)
221 {
222 	struct nfs_inode *nfsi = NFS_I(inode);
223 	int mode = inode->i_mode;
224 
225 	nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
226 
227 	nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
228 	nfsi->attrtimeo_timestamp = jiffies;
229 
230 	memset(NFS_I(inode)->cookieverf, 0, sizeof(NFS_I(inode)->cookieverf));
231 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
232 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
233 					| NFS_INO_INVALID_DATA
234 					| NFS_INO_INVALID_ACCESS
235 					| NFS_INO_INVALID_ACL
236 					| NFS_INO_REVAL_PAGECACHE);
237 	} else
238 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
239 					| NFS_INO_INVALID_ACCESS
240 					| NFS_INO_INVALID_ACL
241 					| NFS_INO_REVAL_PAGECACHE);
242 	nfs_zap_label_cache_locked(nfsi);
243 }
244 
245 void nfs_zap_caches(struct inode *inode)
246 {
247 	spin_lock(&inode->i_lock);
248 	nfs_zap_caches_locked(inode);
249 	spin_unlock(&inode->i_lock);
250 }
251 
252 void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
253 {
254 	if (mapping->nrpages != 0) {
255 		spin_lock(&inode->i_lock);
256 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
257 		spin_unlock(&inode->i_lock);
258 	}
259 }
260 
261 void nfs_zap_acl_cache(struct inode *inode)
262 {
263 	void (*clear_acl_cache)(struct inode *);
264 
265 	clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
266 	if (clear_acl_cache != NULL)
267 		clear_acl_cache(inode);
268 	spin_lock(&inode->i_lock);
269 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
270 	spin_unlock(&inode->i_lock);
271 }
272 EXPORT_SYMBOL_GPL(nfs_zap_acl_cache);
273 
274 void nfs_invalidate_atime(struct inode *inode)
275 {
276 	spin_lock(&inode->i_lock);
277 	nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
278 	spin_unlock(&inode->i_lock);
279 }
280 EXPORT_SYMBOL_GPL(nfs_invalidate_atime);
281 
282 /*
283  * Invalidate, but do not unhash, the inode.
284  * NB: must be called with inode->i_lock held!
285  */
286 static void nfs_set_inode_stale_locked(struct inode *inode)
287 {
288 	set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
289 	nfs_zap_caches_locked(inode);
290 	trace_nfs_set_inode_stale(inode);
291 }
292 
293 void nfs_set_inode_stale(struct inode *inode)
294 {
295 	spin_lock(&inode->i_lock);
296 	nfs_set_inode_stale_locked(inode);
297 	spin_unlock(&inode->i_lock);
298 }
299 
300 struct nfs_find_desc {
301 	struct nfs_fh		*fh;
302 	struct nfs_fattr	*fattr;
303 };
304 
305 /*
306  * In NFSv3 we can have 64bit inode numbers. In order to support
307  * this, and re-exported directories (also seen in NFSv2)
308  * we are forced to allow 2 different inodes to have the same
309  * i_ino.
310  */
311 static int
312 nfs_find_actor(struct inode *inode, void *opaque)
313 {
314 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
315 	struct nfs_fh		*fh = desc->fh;
316 	struct nfs_fattr	*fattr = desc->fattr;
317 
318 	if (NFS_FILEID(inode) != fattr->fileid)
319 		return 0;
320 	if ((S_IFMT & inode->i_mode) != (S_IFMT & fattr->mode))
321 		return 0;
322 	if (nfs_compare_fh(NFS_FH(inode), fh))
323 		return 0;
324 	if (is_bad_inode(inode) || NFS_STALE(inode))
325 		return 0;
326 	return 1;
327 }
328 
329 static int
330 nfs_init_locked(struct inode *inode, void *opaque)
331 {
332 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
333 	struct nfs_fattr	*fattr = desc->fattr;
334 
335 	set_nfs_fileid(inode, fattr->fileid);
336 	inode->i_mode = fattr->mode;
337 	nfs_copy_fh(NFS_FH(inode), desc->fh);
338 	return 0;
339 }
340 
341 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
342 static void nfs_clear_label_invalid(struct inode *inode)
343 {
344 	spin_lock(&inode->i_lock);
345 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_LABEL;
346 	spin_unlock(&inode->i_lock);
347 }
348 
349 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
350 					struct nfs4_label *label)
351 {
352 	int error;
353 
354 	if (label == NULL)
355 		return;
356 
357 	if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
358 		error = security_inode_notifysecctx(inode, label->label,
359 				label->len);
360 		if (error)
361 			printk(KERN_ERR "%s() %s %d "
362 					"security_inode_notifysecctx() %d\n",
363 					__func__,
364 					(char *)label->label,
365 					label->len, error);
366 		nfs_clear_label_invalid(inode);
367 	}
368 }
369 
370 struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
371 {
372 	struct nfs4_label *label = NULL;
373 	int minor_version = server->nfs_client->cl_minorversion;
374 
375 	if (minor_version < 2)
376 		return label;
377 
378 	if (!(server->caps & NFS_CAP_SECURITY_LABEL))
379 		return label;
380 
381 	label = kzalloc(sizeof(struct nfs4_label), flags);
382 	if (label == NULL)
383 		return ERR_PTR(-ENOMEM);
384 
385 	label->label = kzalloc(NFS4_MAXLABELLEN, flags);
386 	if (label->label == NULL) {
387 		kfree(label);
388 		return ERR_PTR(-ENOMEM);
389 	}
390 	label->len = NFS4_MAXLABELLEN;
391 
392 	return label;
393 }
394 EXPORT_SYMBOL_GPL(nfs4_label_alloc);
395 #else
396 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
397 					struct nfs4_label *label)
398 {
399 }
400 #endif
401 EXPORT_SYMBOL_GPL(nfs_setsecurity);
402 
403 /* Search for inode identified by fh, fileid and i_mode in inode cache. */
404 struct inode *
405 nfs_ilookup(struct super_block *sb, struct nfs_fattr *fattr, struct nfs_fh *fh)
406 {
407 	struct nfs_find_desc desc = {
408 		.fh	= fh,
409 		.fattr	= fattr,
410 	};
411 	struct inode *inode;
412 	unsigned long hash;
413 
414 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID) ||
415 	    !(fattr->valid & NFS_ATTR_FATTR_TYPE))
416 		return NULL;
417 
418 	hash = nfs_fattr_to_ino_t(fattr);
419 	inode = ilookup5(sb, hash, nfs_find_actor, &desc);
420 
421 	dprintk("%s: returning %p\n", __func__, inode);
422 	return inode;
423 }
424 
425 /*
426  * This is our front-end to iget that looks up inodes by file handle
427  * instead of inode number.
428  */
429 struct inode *
430 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, struct nfs4_label *label)
431 {
432 	struct nfs_find_desc desc = {
433 		.fh	= fh,
434 		.fattr	= fattr
435 	};
436 	struct inode *inode = ERR_PTR(-ENOENT);
437 	unsigned long hash;
438 
439 	nfs_attr_check_mountpoint(sb, fattr);
440 
441 	if (nfs_attr_use_mounted_on_fileid(fattr))
442 		fattr->fileid = fattr->mounted_on_fileid;
443 	else if ((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0)
444 		goto out_no_inode;
445 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
446 		goto out_no_inode;
447 
448 	hash = nfs_fattr_to_ino_t(fattr);
449 
450 	inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
451 	if (inode == NULL) {
452 		inode = ERR_PTR(-ENOMEM);
453 		goto out_no_inode;
454 	}
455 
456 	if (inode->i_state & I_NEW) {
457 		struct nfs_inode *nfsi = NFS_I(inode);
458 		unsigned long now = jiffies;
459 
460 		/* We set i_ino for the few things that still rely on it,
461 		 * such as stat(2) */
462 		inode->i_ino = hash;
463 
464 		/* We can't support update_atime(), since the server will reset it */
465 		inode->i_flags |= S_NOATIME|S_NOCMTIME;
466 		inode->i_mode = fattr->mode;
467 		nfsi->cache_validity = 0;
468 		if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
469 				&& nfs_server_capable(inode, NFS_CAP_MODE))
470 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
471 		/* Why so? Because we want revalidate for devices/FIFOs, and
472 		 * that's precisely what we have in nfs_file_inode_operations.
473 		 */
474 		inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
475 		if (S_ISREG(inode->i_mode)) {
476 			inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
477 			inode->i_data.a_ops = &nfs_file_aops;
478 		} else if (S_ISDIR(inode->i_mode)) {
479 			inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
480 			inode->i_fop = &nfs_dir_operations;
481 			inode->i_data.a_ops = &nfs_dir_aops;
482 			/* Deal with crossing mountpoints */
483 			if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
484 					fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
485 				if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
486 					inode->i_op = &nfs_referral_inode_operations;
487 				else
488 					inode->i_op = &nfs_mountpoint_inode_operations;
489 				inode->i_fop = NULL;
490 				inode->i_flags |= S_AUTOMOUNT;
491 			}
492 		} else if (S_ISLNK(inode->i_mode)) {
493 			inode->i_op = &nfs_symlink_inode_operations;
494 			inode_nohighmem(inode);
495 		} else
496 			init_special_inode(inode, inode->i_mode, fattr->rdev);
497 
498 		memset(&inode->i_atime, 0, sizeof(inode->i_atime));
499 		memset(&inode->i_mtime, 0, sizeof(inode->i_mtime));
500 		memset(&inode->i_ctime, 0, sizeof(inode->i_ctime));
501 		inode_set_iversion_raw(inode, 0);
502 		inode->i_size = 0;
503 		clear_nlink(inode);
504 		inode->i_uid = make_kuid(&init_user_ns, -2);
505 		inode->i_gid = make_kgid(&init_user_ns, -2);
506 		inode->i_blocks = 0;
507 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
508 		nfsi->write_io = 0;
509 		nfsi->read_io = 0;
510 
511 		nfsi->read_cache_jiffies = fattr->time_start;
512 		nfsi->attr_gencount = fattr->gencount;
513 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
514 			inode->i_atime = fattr->atime;
515 		else if (nfs_server_capable(inode, NFS_CAP_ATIME))
516 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
517 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
518 			inode->i_mtime = fattr->mtime;
519 		else if (nfs_server_capable(inode, NFS_CAP_MTIME))
520 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
521 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
522 			inode->i_ctime = fattr->ctime;
523 		else if (nfs_server_capable(inode, NFS_CAP_CTIME))
524 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CTIME);
525 		if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
526 			inode_set_iversion_raw(inode, fattr->change_attr);
527 		else
528 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE);
529 		if (fattr->valid & NFS_ATTR_FATTR_SIZE)
530 			inode->i_size = nfs_size_to_loff_t(fattr->size);
531 		else
532 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_SIZE);
533 		if (fattr->valid & NFS_ATTR_FATTR_NLINK)
534 			set_nlink(inode, fattr->nlink);
535 		else if (nfs_server_capable(inode, NFS_CAP_NLINK))
536 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
537 		if (fattr->valid & NFS_ATTR_FATTR_OWNER)
538 			inode->i_uid = fattr->uid;
539 		else if (nfs_server_capable(inode, NFS_CAP_OWNER))
540 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
541 		if (fattr->valid & NFS_ATTR_FATTR_GROUP)
542 			inode->i_gid = fattr->gid;
543 		else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
544 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
545 		if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
546 			inode->i_blocks = fattr->du.nfs2.blocks;
547 		if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
548 			/*
549 			 * report the blocks in 512byte units
550 			 */
551 			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
552 		}
553 
554 		if (nfsi->cache_validity != 0)
555 			nfsi->cache_validity |= NFS_INO_REVAL_FORCED;
556 
557 		nfs_setsecurity(inode, fattr, label);
558 
559 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
560 		nfsi->attrtimeo_timestamp = now;
561 		nfsi->access_cache = RB_ROOT;
562 
563 		nfs_fscache_init_inode(inode);
564 
565 		unlock_new_inode(inode);
566 	} else {
567 		int err = nfs_refresh_inode(inode, fattr);
568 		if (err < 0) {
569 			iput(inode);
570 			inode = ERR_PTR(err);
571 			goto out_no_inode;
572 		}
573 	}
574 	dprintk("NFS: nfs_fhget(%s/%Lu fh_crc=0x%08x ct=%d)\n",
575 		inode->i_sb->s_id,
576 		(unsigned long long)NFS_FILEID(inode),
577 		nfs_display_fhandle_hash(fh),
578 		atomic_read(&inode->i_count));
579 
580 out:
581 	return inode;
582 
583 out_no_inode:
584 	dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
585 	goto out;
586 }
587 EXPORT_SYMBOL_GPL(nfs_fhget);
588 
589 #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)
590 
591 int
592 nfs_setattr(struct dentry *dentry, struct iattr *attr)
593 {
594 	struct inode *inode = d_inode(dentry);
595 	struct nfs_fattr *fattr;
596 	int error = 0;
597 
598 	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
599 
600 	/* skip mode change if it's just for clearing setuid/setgid */
601 	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
602 		attr->ia_valid &= ~ATTR_MODE;
603 
604 	if (attr->ia_valid & ATTR_SIZE) {
605 		BUG_ON(!S_ISREG(inode->i_mode));
606 
607 		error = inode_newsize_ok(inode, attr->ia_size);
608 		if (error)
609 			return error;
610 
611 		if (attr->ia_size == i_size_read(inode))
612 			attr->ia_valid &= ~ATTR_SIZE;
613 	}
614 
615 	/* Optimization: if the end result is no change, don't RPC */
616 	attr->ia_valid &= NFS_VALID_ATTRS;
617 	if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
618 		return 0;
619 
620 	trace_nfs_setattr_enter(inode);
621 
622 	/* Write all dirty data */
623 	if (S_ISREG(inode->i_mode))
624 		nfs_sync_inode(inode);
625 
626 	fattr = nfs_alloc_fattr();
627 	if (fattr == NULL) {
628 		error = -ENOMEM;
629 		goto out;
630 	}
631 
632 	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
633 	if (error == 0)
634 		error = nfs_refresh_inode(inode, fattr);
635 	nfs_free_fattr(fattr);
636 out:
637 	trace_nfs_setattr_exit(inode, error);
638 	return error;
639 }
640 EXPORT_SYMBOL_GPL(nfs_setattr);
641 
642 /**
643  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
644  * @inode: inode of the file used
645  * @offset: file offset to start truncating
646  *
647  * This is a copy of the common vmtruncate, but with the locking
648  * corrected to take into account the fact that NFS requires
649  * inode->i_size to be updated under the inode->i_lock.
650  * Note: must be called with inode->i_lock held!
651  */
652 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
653 {
654 	int err;
655 
656 	err = inode_newsize_ok(inode, offset);
657 	if (err)
658 		goto out;
659 
660 	i_size_write(inode, offset);
661 	/* Optimisation */
662 	if (offset == 0)
663 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_DATA |
664 				NFS_INO_DATA_INVAL_DEFER);
665 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE;
666 
667 	spin_unlock(&inode->i_lock);
668 	truncate_pagecache(inode, offset);
669 	spin_lock(&inode->i_lock);
670 out:
671 	return err;
672 }
673 
674 /**
675  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
676  * @inode: pointer to struct inode
677  * @attr: pointer to struct iattr
678  * @fattr: pointer to struct nfs_fattr
679  *
680  * Note: we do this in the *proc.c in order to ensure that
681  *       it works for things like exclusive creates too.
682  */
683 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr,
684 		struct nfs_fattr *fattr)
685 {
686 	/* Barrier: bump the attribute generation count. */
687 	nfs_fattr_set_barrier(fattr);
688 
689 	spin_lock(&inode->i_lock);
690 	NFS_I(inode)->attr_gencount = fattr->gencount;
691 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
692 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
693 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
694 		nfs_vmtruncate(inode, attr->ia_size);
695 	}
696 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
697 		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_CTIME;
698 		if ((attr->ia_valid & ATTR_MODE) != 0) {
699 			int mode = attr->ia_mode & S_IALLUGO;
700 			mode |= inode->i_mode & ~S_IALLUGO;
701 			inode->i_mode = mode;
702 		}
703 		if ((attr->ia_valid & ATTR_UID) != 0)
704 			inode->i_uid = attr->ia_uid;
705 		if ((attr->ia_valid & ATTR_GID) != 0)
706 			inode->i_gid = attr->ia_gid;
707 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
708 			inode->i_ctime = fattr->ctime;
709 		else
710 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
711 					| NFS_INO_INVALID_CTIME);
712 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS
713 				| NFS_INO_INVALID_ACL);
714 	}
715 	if (attr->ia_valid & (ATTR_ATIME_SET|ATTR_ATIME)) {
716 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_ATIME
717 				| NFS_INO_INVALID_CTIME);
718 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
719 			inode->i_atime = fattr->atime;
720 		else if (attr->ia_valid & ATTR_ATIME_SET)
721 			inode->i_atime = attr->ia_atime;
722 		else
723 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
724 
725 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
726 			inode->i_ctime = fattr->ctime;
727 		else
728 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
729 					| NFS_INO_INVALID_CTIME);
730 	}
731 	if (attr->ia_valid & (ATTR_MTIME_SET|ATTR_MTIME)) {
732 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_MTIME
733 				| NFS_INO_INVALID_CTIME);
734 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
735 			inode->i_mtime = fattr->mtime;
736 		else if (attr->ia_valid & ATTR_MTIME_SET)
737 			inode->i_mtime = attr->ia_mtime;
738 		else
739 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
740 
741 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
742 			inode->i_ctime = fattr->ctime;
743 		else
744 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
745 					| NFS_INO_INVALID_CTIME);
746 	}
747 	if (fattr->valid)
748 		nfs_update_inode(inode, fattr);
749 	spin_unlock(&inode->i_lock);
750 }
751 EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
752 
753 static void nfs_readdirplus_parent_cache_miss(struct dentry *dentry)
754 {
755 	struct dentry *parent;
756 
757 	if (!nfs_server_capable(d_inode(dentry), NFS_CAP_READDIRPLUS))
758 		return;
759 	parent = dget_parent(dentry);
760 	nfs_force_use_readdirplus(d_inode(parent));
761 	dput(parent);
762 }
763 
764 static void nfs_readdirplus_parent_cache_hit(struct dentry *dentry)
765 {
766 	struct dentry *parent;
767 
768 	if (!nfs_server_capable(d_inode(dentry), NFS_CAP_READDIRPLUS))
769 		return;
770 	parent = dget_parent(dentry);
771 	nfs_advise_use_readdirplus(d_inode(parent));
772 	dput(parent);
773 }
774 
775 static bool nfs_need_revalidate_inode(struct inode *inode)
776 {
777 	if (NFS_I(inode)->cache_validity &
778 			(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
779 		return true;
780 	if (nfs_attribute_cache_expired(inode))
781 		return true;
782 	return false;
783 }
784 
785 int nfs_getattr(const struct path *path, struct kstat *stat,
786 		u32 request_mask, unsigned int query_flags)
787 {
788 	struct inode *inode = d_inode(path->dentry);
789 	struct nfs_server *server = NFS_SERVER(inode);
790 	unsigned long cache_validity;
791 	int err = 0;
792 	bool force_sync = query_flags & AT_STATX_FORCE_SYNC;
793 	bool do_update = false;
794 
795 	trace_nfs_getattr_enter(inode);
796 
797 	if ((query_flags & AT_STATX_DONT_SYNC) && !force_sync)
798 		goto out_no_update;
799 
800 	/* Flush out writes to the server in order to update c/mtime.  */
801 	if ((request_mask & (STATX_CTIME|STATX_MTIME)) &&
802 			S_ISREG(inode->i_mode)) {
803 		err = filemap_write_and_wait(inode->i_mapping);
804 		if (err)
805 			goto out;
806 	}
807 
808 	/*
809 	 * We may force a getattr if the user cares about atime.
810 	 *
811 	 * Note that we only have to check the vfsmount flags here:
812 	 *  - NFS always sets S_NOATIME by so checking it would give a
813 	 *    bogus result
814 	 *  - NFS never sets SB_NOATIME or SB_NODIRATIME so there is
815 	 *    no point in checking those.
816 	 */
817 	if ((path->mnt->mnt_flags & MNT_NOATIME) ||
818 	    ((path->mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
819 		request_mask &= ~STATX_ATIME;
820 
821 	/* Is the user requesting attributes that might need revalidation? */
822 	if (!(request_mask & (STATX_MODE|STATX_NLINK|STATX_ATIME|STATX_CTIME|
823 					STATX_MTIME|STATX_UID|STATX_GID|
824 					STATX_SIZE|STATX_BLOCKS)))
825 		goto out_no_revalidate;
826 
827 	/* Check whether the cached attributes are stale */
828 	do_update |= force_sync || nfs_attribute_cache_expired(inode);
829 	cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
830 	do_update |= cache_validity &
831 		(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL);
832 	if (request_mask & STATX_ATIME)
833 		do_update |= cache_validity & NFS_INO_INVALID_ATIME;
834 	if (request_mask & (STATX_CTIME|STATX_MTIME))
835 		do_update |= cache_validity & NFS_INO_REVAL_PAGECACHE;
836 	if (request_mask & STATX_BLOCKS)
837 		do_update |= cache_validity & NFS_INO_INVALID_BLOCKS;
838 	if (do_update) {
839 		/* Update the attribute cache */
840 		if (!(server->flags & NFS_MOUNT_NOAC))
841 			nfs_readdirplus_parent_cache_miss(path->dentry);
842 		else
843 			nfs_readdirplus_parent_cache_hit(path->dentry);
844 		err = __nfs_revalidate_inode(server, inode);
845 		if (err)
846 			goto out;
847 	} else
848 		nfs_readdirplus_parent_cache_hit(path->dentry);
849 out_no_revalidate:
850 	/* Only return attributes that were revalidated. */
851 	stat->result_mask &= request_mask;
852 out_no_update:
853 	generic_fillattr(inode, stat);
854 	stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
855 	if (S_ISDIR(inode->i_mode))
856 		stat->blksize = NFS_SERVER(inode)->dtsize;
857 out:
858 	trace_nfs_getattr_exit(inode, err);
859 	return err;
860 }
861 EXPORT_SYMBOL_GPL(nfs_getattr);
862 
863 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
864 {
865 	refcount_set(&l_ctx->count, 1);
866 	l_ctx->lockowner = current->files;
867 	INIT_LIST_HEAD(&l_ctx->list);
868 	atomic_set(&l_ctx->io_count, 0);
869 }
870 
871 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
872 {
873 	struct nfs_lock_context *pos;
874 
875 	list_for_each_entry_rcu(pos, &ctx->lock_context.list, list) {
876 		if (pos->lockowner != current->files)
877 			continue;
878 		if (refcount_inc_not_zero(&pos->count))
879 			return pos;
880 	}
881 	return NULL;
882 }
883 
884 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
885 {
886 	struct nfs_lock_context *res, *new = NULL;
887 	struct inode *inode = d_inode(ctx->dentry);
888 
889 	rcu_read_lock();
890 	res = __nfs_find_lock_context(ctx);
891 	rcu_read_unlock();
892 	if (res == NULL) {
893 		new = kmalloc(sizeof(*new), GFP_KERNEL);
894 		if (new == NULL)
895 			return ERR_PTR(-ENOMEM);
896 		nfs_init_lock_context(new);
897 		spin_lock(&inode->i_lock);
898 		res = __nfs_find_lock_context(ctx);
899 		if (res == NULL) {
900 			new->open_context = get_nfs_open_context(ctx);
901 			if (new->open_context) {
902 				list_add_tail_rcu(&new->list,
903 						&ctx->lock_context.list);
904 				res = new;
905 				new = NULL;
906 			} else
907 				res = ERR_PTR(-EBADF);
908 		}
909 		spin_unlock(&inode->i_lock);
910 		kfree(new);
911 	}
912 	return res;
913 }
914 EXPORT_SYMBOL_GPL(nfs_get_lock_context);
915 
916 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
917 {
918 	struct nfs_open_context *ctx = l_ctx->open_context;
919 	struct inode *inode = d_inode(ctx->dentry);
920 
921 	if (!refcount_dec_and_lock(&l_ctx->count, &inode->i_lock))
922 		return;
923 	list_del_rcu(&l_ctx->list);
924 	spin_unlock(&inode->i_lock);
925 	put_nfs_open_context(ctx);
926 	kfree_rcu(l_ctx, rcu_head);
927 }
928 EXPORT_SYMBOL_GPL(nfs_put_lock_context);
929 
930 /**
931  * nfs_close_context - Common close_context() routine NFSv2/v3
932  * @ctx: pointer to context
933  * @is_sync: is this a synchronous close
934  *
935  * Ensure that the attributes are up to date if we're mounted
936  * with close-to-open semantics and we have cached data that will
937  * need to be revalidated on open.
938  */
939 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
940 {
941 	struct nfs_inode *nfsi;
942 	struct inode *inode;
943 	struct nfs_server *server;
944 
945 	if (!(ctx->mode & FMODE_WRITE))
946 		return;
947 	if (!is_sync)
948 		return;
949 	inode = d_inode(ctx->dentry);
950 	if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
951 		return;
952 	nfsi = NFS_I(inode);
953 	if (inode->i_mapping->nrpages == 0)
954 		return;
955 	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
956 		return;
957 	if (!list_empty(&nfsi->open_files))
958 		return;
959 	server = NFS_SERVER(inode);
960 	if (server->flags & NFS_MOUNT_NOCTO)
961 		return;
962 	nfs_revalidate_inode(server, inode);
963 }
964 EXPORT_SYMBOL_GPL(nfs_close_context);
965 
966 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry,
967 						fmode_t f_mode,
968 						struct file *filp)
969 {
970 	struct nfs_open_context *ctx;
971 
972 	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
973 	if (!ctx)
974 		return ERR_PTR(-ENOMEM);
975 	nfs_sb_active(dentry->d_sb);
976 	ctx->dentry = dget(dentry);
977 	if (filp)
978 		ctx->cred = get_cred(filp->f_cred);
979 	else
980 		ctx->cred = get_current_cred();
981 	ctx->ll_cred = NULL;
982 	ctx->state = NULL;
983 	ctx->mode = f_mode;
984 	ctx->flags = 0;
985 	ctx->error = 0;
986 	ctx->flock_owner = (fl_owner_t)filp;
987 	nfs_init_lock_context(&ctx->lock_context);
988 	ctx->lock_context.open_context = ctx;
989 	INIT_LIST_HEAD(&ctx->list);
990 	ctx->mdsthreshold = NULL;
991 	return ctx;
992 }
993 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
994 
995 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
996 {
997 	if (ctx != NULL && refcount_inc_not_zero(&ctx->lock_context.count))
998 		return ctx;
999 	return NULL;
1000 }
1001 EXPORT_SYMBOL_GPL(get_nfs_open_context);
1002 
1003 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
1004 {
1005 	struct inode *inode = d_inode(ctx->dentry);
1006 	struct super_block *sb = ctx->dentry->d_sb;
1007 
1008 	if (!refcount_dec_and_test(&ctx->lock_context.count))
1009 		return;
1010 	if (!list_empty(&ctx->list)) {
1011 		spin_lock(&inode->i_lock);
1012 		list_del_rcu(&ctx->list);
1013 		spin_unlock(&inode->i_lock);
1014 	}
1015 	if (inode != NULL)
1016 		NFS_PROTO(inode)->close_context(ctx, is_sync);
1017 	put_cred(ctx->cred);
1018 	dput(ctx->dentry);
1019 	nfs_sb_deactive(sb);
1020 	put_rpccred(ctx->ll_cred);
1021 	kfree(ctx->mdsthreshold);
1022 	kfree_rcu(ctx, rcu_head);
1023 }
1024 
1025 void put_nfs_open_context(struct nfs_open_context *ctx)
1026 {
1027 	__put_nfs_open_context(ctx, 0);
1028 }
1029 EXPORT_SYMBOL_GPL(put_nfs_open_context);
1030 
1031 static void put_nfs_open_context_sync(struct nfs_open_context *ctx)
1032 {
1033 	__put_nfs_open_context(ctx, 1);
1034 }
1035 
1036 /*
1037  * Ensure that mmap has a recent RPC credential for use when writing out
1038  * shared pages
1039  */
1040 void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
1041 {
1042 	struct inode *inode = d_inode(ctx->dentry);
1043 	struct nfs_inode *nfsi = NFS_I(inode);
1044 
1045 	spin_lock(&inode->i_lock);
1046 	if (list_empty(&nfsi->open_files) &&
1047 	    (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER))
1048 		nfsi->cache_validity |= NFS_INO_INVALID_DATA |
1049 			NFS_INO_REVAL_FORCED;
1050 	list_add_tail_rcu(&ctx->list, &nfsi->open_files);
1051 	spin_unlock(&inode->i_lock);
1052 }
1053 EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
1054 
1055 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
1056 {
1057 	filp->private_data = get_nfs_open_context(ctx);
1058 	if (list_empty(&ctx->list))
1059 		nfs_inode_attach_open_context(ctx);
1060 }
1061 EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
1062 
1063 /*
1064  * Given an inode, search for an open context with the desired characteristics
1065  */
1066 struct nfs_open_context *nfs_find_open_context(struct inode *inode, const struct cred *cred, fmode_t mode)
1067 {
1068 	struct nfs_inode *nfsi = NFS_I(inode);
1069 	struct nfs_open_context *pos, *ctx = NULL;
1070 
1071 	rcu_read_lock();
1072 	list_for_each_entry_rcu(pos, &nfsi->open_files, list) {
1073 		if (cred != NULL && cred_fscmp(pos->cred, cred) != 0)
1074 			continue;
1075 		if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
1076 			continue;
1077 		ctx = get_nfs_open_context(pos);
1078 		if (ctx)
1079 			break;
1080 	}
1081 	rcu_read_unlock();
1082 	return ctx;
1083 }
1084 
1085 void nfs_file_clear_open_context(struct file *filp)
1086 {
1087 	struct nfs_open_context *ctx = nfs_file_open_context(filp);
1088 
1089 	if (ctx) {
1090 		struct inode *inode = d_inode(ctx->dentry);
1091 
1092 		/*
1093 		 * We fatal error on write before. Try to writeback
1094 		 * every page again.
1095 		 */
1096 		if (ctx->error < 0)
1097 			invalidate_inode_pages2(inode->i_mapping);
1098 		filp->private_data = NULL;
1099 		put_nfs_open_context_sync(ctx);
1100 	}
1101 }
1102 
1103 /*
1104  * These allocate and release file read/write context information.
1105  */
1106 int nfs_open(struct inode *inode, struct file *filp)
1107 {
1108 	struct nfs_open_context *ctx;
1109 
1110 	ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode, filp);
1111 	if (IS_ERR(ctx))
1112 		return PTR_ERR(ctx);
1113 	nfs_file_set_open_context(filp, ctx);
1114 	put_nfs_open_context(ctx);
1115 	nfs_fscache_open_file(inode, filp);
1116 	return 0;
1117 }
1118 EXPORT_SYMBOL_GPL(nfs_open);
1119 
1120 /*
1121  * This function is called whenever some part of NFS notices that
1122  * the cached attributes have to be refreshed.
1123  */
1124 int
1125 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1126 {
1127 	int		 status = -ESTALE;
1128 	struct nfs4_label *label = NULL;
1129 	struct nfs_fattr *fattr = NULL;
1130 	struct nfs_inode *nfsi = NFS_I(inode);
1131 
1132 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Lu)\n",
1133 		inode->i_sb->s_id, (unsigned long long)NFS_FILEID(inode));
1134 
1135 	trace_nfs_revalidate_inode_enter(inode);
1136 
1137 	if (is_bad_inode(inode))
1138 		goto out;
1139 	if (NFS_STALE(inode))
1140 		goto out;
1141 
1142 	/* pNFS: Attributes aren't updated until we layoutcommit */
1143 	if (S_ISREG(inode->i_mode)) {
1144 		status = pnfs_sync_inode(inode, false);
1145 		if (status)
1146 			goto out;
1147 	}
1148 
1149 	status = -ENOMEM;
1150 	fattr = nfs_alloc_fattr();
1151 	if (fattr == NULL)
1152 		goto out;
1153 
1154 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
1155 
1156 	label = nfs4_label_alloc(NFS_SERVER(inode), GFP_KERNEL);
1157 	if (IS_ERR(label)) {
1158 		status = PTR_ERR(label);
1159 		goto out;
1160 	}
1161 
1162 	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr,
1163 			label, inode);
1164 	if (status != 0) {
1165 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) getattr failed, error=%d\n",
1166 			 inode->i_sb->s_id,
1167 			 (unsigned long long)NFS_FILEID(inode), status);
1168 		switch (status) {
1169 		case -ETIMEDOUT:
1170 			/* A soft timeout occurred. Use cached information? */
1171 			if (server->flags & NFS_MOUNT_SOFTREVAL)
1172 				status = 0;
1173 			break;
1174 		case -ESTALE:
1175 			if (!S_ISDIR(inode->i_mode))
1176 				nfs_set_inode_stale(inode);
1177 			else
1178 				nfs_zap_caches(inode);
1179 		}
1180 		goto err_out;
1181 	}
1182 
1183 	status = nfs_refresh_inode(inode, fattr);
1184 	if (status) {
1185 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) refresh failed, error=%d\n",
1186 			 inode->i_sb->s_id,
1187 			 (unsigned long long)NFS_FILEID(inode), status);
1188 		goto err_out;
1189 	}
1190 
1191 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
1192 		nfs_zap_acl_cache(inode);
1193 
1194 	nfs_setsecurity(inode, fattr, label);
1195 
1196 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) revalidation complete\n",
1197 		inode->i_sb->s_id,
1198 		(unsigned long long)NFS_FILEID(inode));
1199 
1200 err_out:
1201 	nfs4_label_free(label);
1202 out:
1203 	nfs_free_fattr(fattr);
1204 	trace_nfs_revalidate_inode_exit(inode, status);
1205 	return status;
1206 }
1207 
1208 int nfs_attribute_cache_expired(struct inode *inode)
1209 {
1210 	if (nfs_have_delegated_attributes(inode))
1211 		return 0;
1212 	return nfs_attribute_timeout(inode);
1213 }
1214 
1215 /**
1216  * nfs_revalidate_inode - Revalidate the inode attributes
1217  * @server: pointer to nfs_server struct
1218  * @inode: pointer to inode struct
1219  *
1220  * Updates inode attribute information by retrieving the data from the server.
1221  */
1222 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1223 {
1224 	if (!nfs_need_revalidate_inode(inode))
1225 		return NFS_STALE(inode) ? -ESTALE : 0;
1226 	return __nfs_revalidate_inode(server, inode);
1227 }
1228 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
1229 
1230 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
1231 {
1232 	struct nfs_inode *nfsi = NFS_I(inode);
1233 	int ret;
1234 
1235 	if (mapping->nrpages != 0) {
1236 		if (S_ISREG(inode->i_mode)) {
1237 			ret = nfs_sync_mapping(mapping);
1238 			if (ret < 0)
1239 				return ret;
1240 		}
1241 		ret = invalidate_inode_pages2(mapping);
1242 		if (ret < 0)
1243 			return ret;
1244 	}
1245 	if (S_ISDIR(inode->i_mode)) {
1246 		spin_lock(&inode->i_lock);
1247 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
1248 		spin_unlock(&inode->i_lock);
1249 	}
1250 	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
1251 	nfs_fscache_wait_on_invalidate(inode);
1252 
1253 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
1254 			inode->i_sb->s_id,
1255 			(unsigned long long)NFS_FILEID(inode));
1256 	return 0;
1257 }
1258 
1259 bool nfs_mapping_need_revalidate_inode(struct inode *inode)
1260 {
1261 	return nfs_check_cache_invalid(inode, NFS_INO_REVAL_PAGECACHE) ||
1262 		NFS_STALE(inode);
1263 }
1264 
1265 int nfs_revalidate_mapping_rcu(struct inode *inode)
1266 {
1267 	struct nfs_inode *nfsi = NFS_I(inode);
1268 	unsigned long *bitlock = &nfsi->flags;
1269 	int ret = 0;
1270 
1271 	if (IS_SWAPFILE(inode))
1272 		goto out;
1273 	if (nfs_mapping_need_revalidate_inode(inode)) {
1274 		ret = -ECHILD;
1275 		goto out;
1276 	}
1277 	spin_lock(&inode->i_lock);
1278 	if (test_bit(NFS_INO_INVALIDATING, bitlock) ||
1279 	    (nfsi->cache_validity & NFS_INO_INVALID_DATA))
1280 		ret = -ECHILD;
1281 	spin_unlock(&inode->i_lock);
1282 out:
1283 	return ret;
1284 }
1285 
1286 /**
1287  * nfs_revalidate_mapping - Revalidate the pagecache
1288  * @inode: pointer to host inode
1289  * @mapping: pointer to mapping
1290  */
1291 int nfs_revalidate_mapping(struct inode *inode,
1292 		struct address_space *mapping)
1293 {
1294 	struct nfs_inode *nfsi = NFS_I(inode);
1295 	unsigned long *bitlock = &nfsi->flags;
1296 	int ret = 0;
1297 
1298 	/* swapfiles are not supposed to be shared. */
1299 	if (IS_SWAPFILE(inode))
1300 		goto out;
1301 
1302 	if (nfs_mapping_need_revalidate_inode(inode)) {
1303 		ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1304 		if (ret < 0)
1305 			goto out;
1306 	}
1307 
1308 	/*
1309 	 * We must clear NFS_INO_INVALID_DATA first to ensure that
1310 	 * invalidations that come in while we're shooting down the mappings
1311 	 * are respected. But, that leaves a race window where one revalidator
1312 	 * can clear the flag, and then another checks it before the mapping
1313 	 * gets invalidated. Fix that by serializing access to this part of
1314 	 * the function.
1315 	 *
1316 	 * At the same time, we need to allow other tasks to see whether we
1317 	 * might be in the middle of invalidating the pages, so we only set
1318 	 * the bit lock here if it looks like we're going to be doing that.
1319 	 */
1320 	for (;;) {
1321 		ret = wait_on_bit_action(bitlock, NFS_INO_INVALIDATING,
1322 					 nfs_wait_bit_killable, TASK_KILLABLE);
1323 		if (ret)
1324 			goto out;
1325 		spin_lock(&inode->i_lock);
1326 		if (test_bit(NFS_INO_INVALIDATING, bitlock)) {
1327 			spin_unlock(&inode->i_lock);
1328 			continue;
1329 		}
1330 		if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1331 			break;
1332 		spin_unlock(&inode->i_lock);
1333 		goto out;
1334 	}
1335 
1336 	set_bit(NFS_INO_INVALIDATING, bitlock);
1337 	smp_wmb();
1338 	nfsi->cache_validity &= ~(NFS_INO_INVALID_DATA|
1339 			NFS_INO_DATA_INVAL_DEFER);
1340 	spin_unlock(&inode->i_lock);
1341 	trace_nfs_invalidate_mapping_enter(inode);
1342 	ret = nfs_invalidate_mapping(inode, mapping);
1343 	trace_nfs_invalidate_mapping_exit(inode, ret);
1344 
1345 	clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
1346 	smp_mb__after_atomic();
1347 	wake_up_bit(bitlock, NFS_INO_INVALIDATING);
1348 out:
1349 	return ret;
1350 }
1351 
1352 static bool nfs_file_has_writers(struct nfs_inode *nfsi)
1353 {
1354 	struct inode *inode = &nfsi->vfs_inode;
1355 
1356 	if (!S_ISREG(inode->i_mode))
1357 		return false;
1358 	if (list_empty(&nfsi->open_files))
1359 		return false;
1360 	return inode_is_open_for_write(inode);
1361 }
1362 
1363 static bool nfs_file_has_buffered_writers(struct nfs_inode *nfsi)
1364 {
1365 	return nfs_file_has_writers(nfsi) && nfs_file_io_is_buffered(nfsi);
1366 }
1367 
1368 static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1369 {
1370 	struct timespec64 ts;
1371 
1372 	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
1373 			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
1374 			&& inode_eq_iversion_raw(inode, fattr->pre_change_attr)) {
1375 		inode_set_iversion_raw(inode, fattr->change_attr);
1376 		if (S_ISDIR(inode->i_mode))
1377 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1378 	}
1379 	/* If we have atomic WCC data, we may update some attributes */
1380 	ts = inode->i_ctime;
1381 	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
1382 			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
1383 			&& timespec64_equal(&ts, &fattr->pre_ctime)) {
1384 		inode->i_ctime = fattr->ctime;
1385 	}
1386 
1387 	ts = inode->i_mtime;
1388 	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
1389 			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
1390 			&& timespec64_equal(&ts, &fattr->pre_mtime)) {
1391 		inode->i_mtime = fattr->mtime;
1392 		if (S_ISDIR(inode->i_mode))
1393 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1394 	}
1395 	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
1396 			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
1397 			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
1398 			&& !nfs_have_writebacks(inode)) {
1399 		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
1400 	}
1401 }
1402 
1403 /**
1404  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1405  * @inode: pointer to inode
1406  * @fattr: updated attributes
1407  *
1408  * Verifies the attribute cache. If we have just changed the attributes,
1409  * so that fattr carries weak cache consistency data, then it may
1410  * also update the ctime/mtime/change_attribute.
1411  */
1412 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1413 {
1414 	struct nfs_inode *nfsi = NFS_I(inode);
1415 	loff_t cur_size, new_isize;
1416 	unsigned long invalid = 0;
1417 	struct timespec64 ts;
1418 
1419 	if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
1420 		return 0;
1421 
1422 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
1423 		/* Only a mounted-on-fileid? Just exit */
1424 		if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
1425 			return 0;
1426 	/* Has the inode gone and changed behind our back? */
1427 	} else if (nfsi->fileid != fattr->fileid) {
1428 		/* Is this perhaps the mounted-on fileid? */
1429 		if ((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) &&
1430 		    nfsi->fileid == fattr->mounted_on_fileid)
1431 			return 0;
1432 		return -ESTALE;
1433 	}
1434 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
1435 		return -ESTALE;
1436 
1437 
1438 	if (!nfs_file_has_buffered_writers(nfsi)) {
1439 		/* Verify a few of the more important attributes */
1440 		if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 && !inode_eq_iversion_raw(inode, fattr->change_attr))
1441 			invalid |= NFS_INO_INVALID_CHANGE
1442 				| NFS_INO_REVAL_PAGECACHE;
1443 
1444 		ts = inode->i_mtime;
1445 		if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec64_equal(&ts, &fattr->mtime))
1446 			invalid |= NFS_INO_INVALID_MTIME;
1447 
1448 		ts = inode->i_ctime;
1449 		if ((fattr->valid & NFS_ATTR_FATTR_CTIME) && !timespec64_equal(&ts, &fattr->ctime))
1450 			invalid |= NFS_INO_INVALID_CTIME;
1451 
1452 		if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1453 			cur_size = i_size_read(inode);
1454 			new_isize = nfs_size_to_loff_t(fattr->size);
1455 			if (cur_size != new_isize)
1456 				invalid |= NFS_INO_INVALID_SIZE
1457 					| NFS_INO_REVAL_PAGECACHE;
1458 		}
1459 	}
1460 
1461 	/* Have any file permissions changed? */
1462 	if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
1463 		invalid |= NFS_INO_INVALID_ACCESS
1464 			| NFS_INO_INVALID_ACL
1465 			| NFS_INO_INVALID_OTHER;
1466 	if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && !uid_eq(inode->i_uid, fattr->uid))
1467 		invalid |= NFS_INO_INVALID_ACCESS
1468 			| NFS_INO_INVALID_ACL
1469 			| NFS_INO_INVALID_OTHER;
1470 	if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && !gid_eq(inode->i_gid, fattr->gid))
1471 		invalid |= NFS_INO_INVALID_ACCESS
1472 			| NFS_INO_INVALID_ACL
1473 			| NFS_INO_INVALID_OTHER;
1474 
1475 	/* Has the link count changed? */
1476 	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
1477 		invalid |= NFS_INO_INVALID_OTHER;
1478 
1479 	ts = inode->i_atime;
1480 	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec64_equal(&ts, &fattr->atime))
1481 		invalid |= NFS_INO_INVALID_ATIME;
1482 
1483 	if (invalid != 0)
1484 		nfs_set_cache_invalid(inode, invalid);
1485 
1486 	nfsi->read_cache_jiffies = fattr->time_start;
1487 	return 0;
1488 }
1489 
1490 static atomic_long_t nfs_attr_generation_counter;
1491 
1492 static unsigned long nfs_read_attr_generation_counter(void)
1493 {
1494 	return atomic_long_read(&nfs_attr_generation_counter);
1495 }
1496 
1497 unsigned long nfs_inc_attr_generation_counter(void)
1498 {
1499 	return atomic_long_inc_return(&nfs_attr_generation_counter);
1500 }
1501 EXPORT_SYMBOL_GPL(nfs_inc_attr_generation_counter);
1502 
1503 void nfs_fattr_init(struct nfs_fattr *fattr)
1504 {
1505 	fattr->valid = 0;
1506 	fattr->time_start = jiffies;
1507 	fattr->gencount = nfs_inc_attr_generation_counter();
1508 	fattr->owner_name = NULL;
1509 	fattr->group_name = NULL;
1510 }
1511 EXPORT_SYMBOL_GPL(nfs_fattr_init);
1512 
1513 /**
1514  * nfs_fattr_set_barrier
1515  * @fattr: attributes
1516  *
1517  * Used to set a barrier after an attribute was updated. This
1518  * barrier ensures that older attributes from RPC calls that may
1519  * have raced with our update cannot clobber these new values.
1520  * Note that you are still responsible for ensuring that other
1521  * operations which change the attribute on the server do not
1522  * collide.
1523  */
1524 void nfs_fattr_set_barrier(struct nfs_fattr *fattr)
1525 {
1526 	fattr->gencount = nfs_inc_attr_generation_counter();
1527 }
1528 
1529 struct nfs_fattr *nfs_alloc_fattr(void)
1530 {
1531 	struct nfs_fattr *fattr;
1532 
1533 	fattr = kmalloc(sizeof(*fattr), GFP_NOFS);
1534 	if (fattr != NULL)
1535 		nfs_fattr_init(fattr);
1536 	return fattr;
1537 }
1538 EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
1539 
1540 struct nfs_fh *nfs_alloc_fhandle(void)
1541 {
1542 	struct nfs_fh *fh;
1543 
1544 	fh = kmalloc(sizeof(struct nfs_fh), GFP_NOFS);
1545 	if (fh != NULL)
1546 		fh->size = 0;
1547 	return fh;
1548 }
1549 EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
1550 
1551 #ifdef NFS_DEBUG
1552 /*
1553  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1554  *                             in the same way that wireshark does
1555  *
1556  * @fh: file handle
1557  *
1558  * For debugging only.
1559  */
1560 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1561 {
1562 	/* wireshark uses 32-bit AUTODIN crc and does a bitwise
1563 	 * not on the result */
1564 	return nfs_fhandle_hash(fh);
1565 }
1566 EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
1567 
1568 /*
1569  * _nfs_display_fhandle - display an NFS file handle on the console
1570  *
1571  * @fh: file handle to display
1572  * @caption: display caption
1573  *
1574  * For debugging only.
1575  */
1576 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1577 {
1578 	unsigned short i;
1579 
1580 	if (fh == NULL || fh->size == 0) {
1581 		printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1582 		return;
1583 	}
1584 
1585 	printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1586 	       caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1587 	for (i = 0; i < fh->size; i += 16) {
1588 		__be32 *pos = (__be32 *)&fh->data[i];
1589 
1590 		switch ((fh->size - i - 1) >> 2) {
1591 		case 0:
1592 			printk(KERN_DEFAULT " %08x\n",
1593 				be32_to_cpup(pos));
1594 			break;
1595 		case 1:
1596 			printk(KERN_DEFAULT " %08x %08x\n",
1597 				be32_to_cpup(pos), be32_to_cpup(pos + 1));
1598 			break;
1599 		case 2:
1600 			printk(KERN_DEFAULT " %08x %08x %08x\n",
1601 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1602 				be32_to_cpup(pos + 2));
1603 			break;
1604 		default:
1605 			printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1606 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1607 				be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1608 		}
1609 	}
1610 }
1611 EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
1612 #endif
1613 
1614 /**
1615  * nfs_inode_attrs_need_update - check if the inode attributes need updating
1616  * @inode: pointer to inode
1617  * @fattr: attributes
1618  *
1619  * Attempt to divine whether or not an RPC call reply carrying stale
1620  * attributes got scheduled after another call carrying updated ones.
1621  *
1622  * To do so, the function first assumes that a more recent ctime means
1623  * that the attributes in fattr are newer, however it also attempt to
1624  * catch the case where ctime either didn't change, or went backwards
1625  * (if someone reset the clock on the server) by looking at whether
1626  * or not this RPC call was started after the inode was last updated.
1627  * Note also the check for wraparound of 'attr_gencount'
1628  *
1629  * The function returns 'true' if it thinks the attributes in 'fattr' are
1630  * more recent than the ones cached in the inode.
1631  *
1632  */
1633 static int nfs_inode_attrs_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1634 {
1635 	const struct nfs_inode *nfsi = NFS_I(inode);
1636 
1637 	return ((long)fattr->gencount - (long)nfsi->attr_gencount) > 0 ||
1638 		((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
1639 }
1640 
1641 static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1642 {
1643 	int ret;
1644 
1645 	trace_nfs_refresh_inode_enter(inode);
1646 
1647 	if (nfs_inode_attrs_need_update(inode, fattr))
1648 		ret = nfs_update_inode(inode, fattr);
1649 	else
1650 		ret = nfs_check_inode_attributes(inode, fattr);
1651 
1652 	trace_nfs_refresh_inode_exit(inode, ret);
1653 	return ret;
1654 }
1655 
1656 /**
1657  * nfs_refresh_inode - try to update the inode attribute cache
1658  * @inode: pointer to inode
1659  * @fattr: updated attributes
1660  *
1661  * Check that an RPC call that returned attributes has not overlapped with
1662  * other recent updates of the inode metadata, then decide whether it is
1663  * safe to do a full update of the inode attributes, or whether just to
1664  * call nfs_check_inode_attributes.
1665  */
1666 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
1667 {
1668 	int status;
1669 
1670 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1671 		return 0;
1672 	spin_lock(&inode->i_lock);
1673 	status = nfs_refresh_inode_locked(inode, fattr);
1674 	spin_unlock(&inode->i_lock);
1675 
1676 	return status;
1677 }
1678 EXPORT_SYMBOL_GPL(nfs_refresh_inode);
1679 
1680 static int nfs_post_op_update_inode_locked(struct inode *inode,
1681 		struct nfs_fattr *fattr, unsigned int invalid)
1682 {
1683 	if (S_ISDIR(inode->i_mode))
1684 		invalid |= NFS_INO_INVALID_DATA;
1685 	nfs_set_cache_invalid(inode, invalid);
1686 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1687 		return 0;
1688 	return nfs_refresh_inode_locked(inode, fattr);
1689 }
1690 
1691 /**
1692  * nfs_post_op_update_inode - try to update the inode attribute cache
1693  * @inode: pointer to inode
1694  * @fattr: updated attributes
1695  *
1696  * After an operation that has changed the inode metadata, mark the
1697  * attribute cache as being invalid, then try to update it.
1698  *
1699  * NB: if the server didn't return any post op attributes, this
1700  * function will force the retrieval of attributes before the next
1701  * NFS request.  Thus it should be used only for operations that
1702  * are expected to change one or more attributes, to avoid
1703  * unnecessary NFS requests and trips through nfs_update_inode().
1704  */
1705 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1706 {
1707 	int status;
1708 
1709 	spin_lock(&inode->i_lock);
1710 	nfs_fattr_set_barrier(fattr);
1711 	status = nfs_post_op_update_inode_locked(inode, fattr,
1712 			NFS_INO_INVALID_CHANGE
1713 			| NFS_INO_INVALID_CTIME
1714 			| NFS_INO_REVAL_FORCED);
1715 	spin_unlock(&inode->i_lock);
1716 
1717 	return status;
1718 }
1719 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
1720 
1721 /**
1722  * nfs_post_op_update_inode_force_wcc_locked - update the inode attribute cache
1723  * @inode: pointer to inode
1724  * @fattr: updated attributes
1725  *
1726  * After an operation that has changed the inode metadata, mark the
1727  * attribute cache as being invalid, then try to update it. Fake up
1728  * weak cache consistency data, if none exist.
1729  *
1730  * This function is mainly designed to be used by the ->write_done() functions.
1731  */
1732 int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr)
1733 {
1734 	int status;
1735 
1736 	/* Don't do a WCC update if these attributes are already stale */
1737 	if ((fattr->valid & NFS_ATTR_FATTR) == 0 ||
1738 			!nfs_inode_attrs_need_update(inode, fattr)) {
1739 		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
1740 				| NFS_ATTR_FATTR_PRESIZE
1741 				| NFS_ATTR_FATTR_PREMTIME
1742 				| NFS_ATTR_FATTR_PRECTIME);
1743 		goto out_noforce;
1744 	}
1745 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1746 			(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
1747 		fattr->pre_change_attr = inode_peek_iversion_raw(inode);
1748 		fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
1749 	}
1750 	if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
1751 			(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
1752 		fattr->pre_ctime = inode->i_ctime;
1753 		fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
1754 	}
1755 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
1756 			(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
1757 		fattr->pre_mtime = inode->i_mtime;
1758 		fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
1759 	}
1760 	if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
1761 			(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
1762 		fattr->pre_size = i_size_read(inode);
1763 		fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
1764 	}
1765 out_noforce:
1766 	status = nfs_post_op_update_inode_locked(inode, fattr,
1767 			NFS_INO_INVALID_CHANGE
1768 			| NFS_INO_INVALID_CTIME
1769 			| NFS_INO_INVALID_MTIME
1770 			| NFS_INO_INVALID_BLOCKS);
1771 	return status;
1772 }
1773 
1774 /**
1775  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
1776  * @inode: pointer to inode
1777  * @fattr: updated attributes
1778  *
1779  * After an operation that has changed the inode metadata, mark the
1780  * attribute cache as being invalid, then try to update it. Fake up
1781  * weak cache consistency data, if none exist.
1782  *
1783  * This function is mainly designed to be used by the ->write_done() functions.
1784  */
1785 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
1786 {
1787 	int status;
1788 
1789 	spin_lock(&inode->i_lock);
1790 	nfs_fattr_set_barrier(fattr);
1791 	status = nfs_post_op_update_inode_force_wcc_locked(inode, fattr);
1792 	spin_unlock(&inode->i_lock);
1793 	return status;
1794 }
1795 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
1796 
1797 
1798 /*
1799  * Many nfs protocol calls return the new file attributes after
1800  * an operation.  Here we update the inode to reflect the state
1801  * of the server's inode.
1802  *
1803  * This is a bit tricky because we have to make sure all dirty pages
1804  * have been sent off to the server before calling invalidate_inode_pages.
1805  * To make sure no other process adds more write requests while we try
1806  * our best to flush them, we make them sleep during the attribute refresh.
1807  *
1808  * A very similar scenario holds for the dir cache.
1809  */
1810 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1811 {
1812 	struct nfs_server *server;
1813 	struct nfs_inode *nfsi = NFS_I(inode);
1814 	loff_t cur_isize, new_isize;
1815 	unsigned long invalid = 0;
1816 	unsigned long now = jiffies;
1817 	unsigned long save_cache_validity;
1818 	bool have_writers = nfs_file_has_buffered_writers(nfsi);
1819 	bool cache_revalidated = true;
1820 	bool attr_changed = false;
1821 	bool have_delegation;
1822 
1823 	dfprintk(VFS, "NFS: %s(%s/%lu fh_crc=0x%08x ct=%d info=0x%x)\n",
1824 			__func__, inode->i_sb->s_id, inode->i_ino,
1825 			nfs_display_fhandle_hash(NFS_FH(inode)),
1826 			atomic_read(&inode->i_count), fattr->valid);
1827 
1828 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
1829 		/* Only a mounted-on-fileid? Just exit */
1830 		if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
1831 			return 0;
1832 	/* Has the inode gone and changed behind our back? */
1833 	} else if (nfsi->fileid != fattr->fileid) {
1834 		/* Is this perhaps the mounted-on fileid? */
1835 		if ((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) &&
1836 		    nfsi->fileid == fattr->mounted_on_fileid)
1837 			return 0;
1838 		printk(KERN_ERR "NFS: server %s error: fileid changed\n"
1839 			"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
1840 			NFS_SERVER(inode)->nfs_client->cl_hostname,
1841 			inode->i_sb->s_id, (long long)nfsi->fileid,
1842 			(long long)fattr->fileid);
1843 		goto out_err;
1844 	}
1845 
1846 	/*
1847 	 * Make sure the inode's type hasn't changed.
1848 	 */
1849 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
1850 		/*
1851 		* Big trouble! The inode has become a different object.
1852 		*/
1853 		printk(KERN_DEBUG "NFS: %s: inode %lu mode changed, %07o to %07o\n",
1854 				__func__, inode->i_ino, inode->i_mode, fattr->mode);
1855 		goto out_err;
1856 	}
1857 
1858 	server = NFS_SERVER(inode);
1859 	/* Update the fsid? */
1860 	if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
1861 			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
1862 			!IS_AUTOMOUNT(inode))
1863 		server->fsid = fattr->fsid;
1864 
1865 	/* Save the delegation state before clearing cache_validity */
1866 	have_delegation = nfs_have_delegated_attributes(inode);
1867 
1868 	/*
1869 	 * Update the read time so we don't revalidate too often.
1870 	 */
1871 	nfsi->read_cache_jiffies = fattr->time_start;
1872 
1873 	save_cache_validity = nfsi->cache_validity;
1874 	nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
1875 			| NFS_INO_INVALID_ATIME
1876 			| NFS_INO_REVAL_FORCED
1877 			| NFS_INO_REVAL_PAGECACHE
1878 			| NFS_INO_INVALID_BLOCKS);
1879 
1880 	/* Do atomic weak cache consistency updates */
1881 	nfs_wcc_update_inode(inode, fattr);
1882 
1883 	if (pnfs_layoutcommit_outstanding(inode)) {
1884 		nfsi->cache_validity |= save_cache_validity & NFS_INO_INVALID_ATTR;
1885 		cache_revalidated = false;
1886 	}
1887 
1888 	/* More cache consistency checks */
1889 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
1890 		if (!inode_eq_iversion_raw(inode, fattr->change_attr)) {
1891 			/* Could it be a race with writeback? */
1892 			if (!(have_writers || have_delegation)) {
1893 				invalid |= NFS_INO_INVALID_DATA
1894 					| NFS_INO_INVALID_ACCESS
1895 					| NFS_INO_INVALID_ACL;
1896 				/* Force revalidate of all attributes */
1897 				save_cache_validity |= NFS_INO_INVALID_CTIME
1898 					| NFS_INO_INVALID_MTIME
1899 					| NFS_INO_INVALID_SIZE
1900 					| NFS_INO_INVALID_OTHER;
1901 				if (S_ISDIR(inode->i_mode))
1902 					nfs_force_lookup_revalidate(inode);
1903 				dprintk("NFS: change_attr change on server for file %s/%ld\n",
1904 						inode->i_sb->s_id,
1905 						inode->i_ino);
1906 			} else if (!have_delegation)
1907 				nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
1908 			inode_set_iversion_raw(inode, fattr->change_attr);
1909 			attr_changed = true;
1910 		}
1911 	} else {
1912 		nfsi->cache_validity |= save_cache_validity &
1913 				(NFS_INO_INVALID_CHANGE
1914 				| NFS_INO_REVAL_PAGECACHE
1915 				| NFS_INO_REVAL_FORCED);
1916 		cache_revalidated = false;
1917 	}
1918 
1919 	if (fattr->valid & NFS_ATTR_FATTR_MTIME) {
1920 		inode->i_mtime = fattr->mtime;
1921 	} else if (server->caps & NFS_CAP_MTIME) {
1922 		nfsi->cache_validity |= save_cache_validity &
1923 				(NFS_INO_INVALID_MTIME
1924 				| NFS_INO_REVAL_FORCED);
1925 		cache_revalidated = false;
1926 	}
1927 
1928 	if (fattr->valid & NFS_ATTR_FATTR_CTIME) {
1929 		inode->i_ctime = fattr->ctime;
1930 	} else if (server->caps & NFS_CAP_CTIME) {
1931 		nfsi->cache_validity |= save_cache_validity &
1932 				(NFS_INO_INVALID_CTIME
1933 				| NFS_INO_REVAL_FORCED);
1934 		cache_revalidated = false;
1935 	}
1936 
1937 	/* Check if our cached file size is stale */
1938 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1939 		new_isize = nfs_size_to_loff_t(fattr->size);
1940 		cur_isize = i_size_read(inode);
1941 		if (new_isize != cur_isize && !have_delegation) {
1942 			/* Do we perhaps have any outstanding writes, or has
1943 			 * the file grown beyond our last write? */
1944 			if (!nfs_have_writebacks(inode) || new_isize > cur_isize) {
1945 				i_size_write(inode, new_isize);
1946 				if (!have_writers)
1947 					invalid |= NFS_INO_INVALID_DATA;
1948 				attr_changed = true;
1949 			}
1950 			dprintk("NFS: isize change on server for file %s/%ld "
1951 					"(%Ld to %Ld)\n",
1952 					inode->i_sb->s_id,
1953 					inode->i_ino,
1954 					(long long)cur_isize,
1955 					(long long)new_isize);
1956 		}
1957 	} else {
1958 		nfsi->cache_validity |= save_cache_validity &
1959 				(NFS_INO_INVALID_SIZE
1960 				| NFS_INO_REVAL_PAGECACHE
1961 				| NFS_INO_REVAL_FORCED);
1962 		cache_revalidated = false;
1963 	}
1964 
1965 
1966 	if (fattr->valid & NFS_ATTR_FATTR_ATIME)
1967 		inode->i_atime = fattr->atime;
1968 	else if (server->caps & NFS_CAP_ATIME) {
1969 		nfsi->cache_validity |= save_cache_validity &
1970 				(NFS_INO_INVALID_ATIME
1971 				| NFS_INO_REVAL_FORCED);
1972 		cache_revalidated = false;
1973 	}
1974 
1975 	if (fattr->valid & NFS_ATTR_FATTR_MODE) {
1976 		if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
1977 			umode_t newmode = inode->i_mode & S_IFMT;
1978 			newmode |= fattr->mode & S_IALLUGO;
1979 			inode->i_mode = newmode;
1980 			invalid |= NFS_INO_INVALID_ACCESS
1981 				| NFS_INO_INVALID_ACL;
1982 			attr_changed = true;
1983 		}
1984 	} else if (server->caps & NFS_CAP_MODE) {
1985 		nfsi->cache_validity |= save_cache_validity &
1986 				(NFS_INO_INVALID_OTHER
1987 				| NFS_INO_REVAL_FORCED);
1988 		cache_revalidated = false;
1989 	}
1990 
1991 	if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
1992 		if (!uid_eq(inode->i_uid, fattr->uid)) {
1993 			invalid |= NFS_INO_INVALID_ACCESS
1994 				| NFS_INO_INVALID_ACL;
1995 			inode->i_uid = fattr->uid;
1996 			attr_changed = true;
1997 		}
1998 	} else if (server->caps & NFS_CAP_OWNER) {
1999 		nfsi->cache_validity |= save_cache_validity &
2000 				(NFS_INO_INVALID_OTHER
2001 				| NFS_INO_REVAL_FORCED);
2002 		cache_revalidated = false;
2003 	}
2004 
2005 	if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
2006 		if (!gid_eq(inode->i_gid, fattr->gid)) {
2007 			invalid |= NFS_INO_INVALID_ACCESS
2008 				| NFS_INO_INVALID_ACL;
2009 			inode->i_gid = fattr->gid;
2010 			attr_changed = true;
2011 		}
2012 	} else if (server->caps & NFS_CAP_OWNER_GROUP) {
2013 		nfsi->cache_validity |= save_cache_validity &
2014 				(NFS_INO_INVALID_OTHER
2015 				| NFS_INO_REVAL_FORCED);
2016 		cache_revalidated = false;
2017 	}
2018 
2019 	if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
2020 		if (inode->i_nlink != fattr->nlink) {
2021 			if (S_ISDIR(inode->i_mode))
2022 				invalid |= NFS_INO_INVALID_DATA;
2023 			set_nlink(inode, fattr->nlink);
2024 			attr_changed = true;
2025 		}
2026 	} else if (server->caps & NFS_CAP_NLINK) {
2027 		nfsi->cache_validity |= save_cache_validity &
2028 				(NFS_INO_INVALID_OTHER
2029 				| NFS_INO_REVAL_FORCED);
2030 		cache_revalidated = false;
2031 	}
2032 
2033 	if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
2034 		/*
2035 		 * report the blocks in 512byte units
2036 		 */
2037 		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
2038 	} else if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
2039 		inode->i_blocks = fattr->du.nfs2.blocks;
2040 	else {
2041 		nfsi->cache_validity |= save_cache_validity &
2042 				(NFS_INO_INVALID_BLOCKS
2043 				| NFS_INO_REVAL_FORCED);
2044 		cache_revalidated = false;
2045 	}
2046 
2047 	/* Update attrtimeo value if we're out of the unstable period */
2048 	if (attr_changed) {
2049 		invalid &= ~NFS_INO_INVALID_ATTR;
2050 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
2051 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
2052 		nfsi->attrtimeo_timestamp = now;
2053 		/* Set barrier to be more recent than all outstanding updates */
2054 		nfsi->attr_gencount = nfs_inc_attr_generation_counter();
2055 	} else {
2056 		if (cache_revalidated) {
2057 			if (!time_in_range_open(now, nfsi->attrtimeo_timestamp,
2058 				nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
2059 				nfsi->attrtimeo <<= 1;
2060 				if (nfsi->attrtimeo > NFS_MAXATTRTIMEO(inode))
2061 					nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
2062 			}
2063 			nfsi->attrtimeo_timestamp = now;
2064 		}
2065 		/* Set the barrier to be more recent than this fattr */
2066 		if ((long)fattr->gencount - (long)nfsi->attr_gencount > 0)
2067 			nfsi->attr_gencount = fattr->gencount;
2068 	}
2069 
2070 	/* Don't invalidate the data if we were to blame */
2071 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
2072 				|| S_ISLNK(inode->i_mode)))
2073 		invalid &= ~NFS_INO_INVALID_DATA;
2074 	nfs_set_cache_invalid(inode, invalid);
2075 
2076 	return 0;
2077  out_err:
2078 	/*
2079 	 * No need to worry about unhashing the dentry, as the
2080 	 * lookup validation will know that the inode is bad.
2081 	 * (But we fall through to invalidate the caches.)
2082 	 */
2083 	nfs_set_inode_stale_locked(inode);
2084 	return -ESTALE;
2085 }
2086 
2087 struct inode *nfs_alloc_inode(struct super_block *sb)
2088 {
2089 	struct nfs_inode *nfsi;
2090 	nfsi = kmem_cache_alloc(nfs_inode_cachep, GFP_KERNEL);
2091 	if (!nfsi)
2092 		return NULL;
2093 	nfsi->flags = 0UL;
2094 	nfsi->cache_validity = 0UL;
2095 #if IS_ENABLED(CONFIG_NFS_V4)
2096 	nfsi->nfs4_acl = NULL;
2097 #endif /* CONFIG_NFS_V4 */
2098 	return &nfsi->vfs_inode;
2099 }
2100 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
2101 
2102 void nfs_free_inode(struct inode *inode)
2103 {
2104 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
2105 }
2106 EXPORT_SYMBOL_GPL(nfs_free_inode);
2107 
2108 static inline void nfs4_init_once(struct nfs_inode *nfsi)
2109 {
2110 #if IS_ENABLED(CONFIG_NFS_V4)
2111 	INIT_LIST_HEAD(&nfsi->open_states);
2112 	nfsi->delegation = NULL;
2113 	init_rwsem(&nfsi->rwsem);
2114 	nfsi->layout = NULL;
2115 #endif
2116 }
2117 
2118 static void init_once(void *foo)
2119 {
2120 	struct nfs_inode *nfsi = (struct nfs_inode *) foo;
2121 
2122 	inode_init_once(&nfsi->vfs_inode);
2123 	INIT_LIST_HEAD(&nfsi->open_files);
2124 	INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
2125 	INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
2126 	INIT_LIST_HEAD(&nfsi->commit_info.list);
2127 	atomic_long_set(&nfsi->nrequests, 0);
2128 	atomic_long_set(&nfsi->commit_info.ncommit, 0);
2129 	atomic_set(&nfsi->commit_info.rpcs_out, 0);
2130 	init_rwsem(&nfsi->rmdir_sem);
2131 	mutex_init(&nfsi->commit_mutex);
2132 	nfs4_init_once(nfsi);
2133 	nfsi->cache_change_attribute = 0;
2134 }
2135 
2136 static int __init nfs_init_inodecache(void)
2137 {
2138 	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
2139 					     sizeof(struct nfs_inode),
2140 					     0, (SLAB_RECLAIM_ACCOUNT|
2141 						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
2142 					     init_once);
2143 	if (nfs_inode_cachep == NULL)
2144 		return -ENOMEM;
2145 
2146 	return 0;
2147 }
2148 
2149 static void nfs_destroy_inodecache(void)
2150 {
2151 	/*
2152 	 * Make sure all delayed rcu free inodes are flushed before we
2153 	 * destroy cache.
2154 	 */
2155 	rcu_barrier();
2156 	kmem_cache_destroy(nfs_inode_cachep);
2157 }
2158 
2159 struct workqueue_struct *nfsiod_workqueue;
2160 EXPORT_SYMBOL_GPL(nfsiod_workqueue);
2161 
2162 /*
2163  * start up the nfsiod workqueue
2164  */
2165 static int nfsiod_start(void)
2166 {
2167 	struct workqueue_struct *wq;
2168 	dprintk("RPC:       creating workqueue nfsiod\n");
2169 	wq = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM, 0);
2170 	if (wq == NULL)
2171 		return -ENOMEM;
2172 	nfsiod_workqueue = wq;
2173 	return 0;
2174 }
2175 
2176 /*
2177  * Destroy the nfsiod workqueue
2178  */
2179 static void nfsiod_stop(void)
2180 {
2181 	struct workqueue_struct *wq;
2182 
2183 	wq = nfsiod_workqueue;
2184 	if (wq == NULL)
2185 		return;
2186 	nfsiod_workqueue = NULL;
2187 	destroy_workqueue(wq);
2188 }
2189 
2190 unsigned int nfs_net_id;
2191 EXPORT_SYMBOL_GPL(nfs_net_id);
2192 
2193 static int nfs_net_init(struct net *net)
2194 {
2195 	nfs_clients_init(net);
2196 	return nfs_fs_proc_net_init(net);
2197 }
2198 
2199 static void nfs_net_exit(struct net *net)
2200 {
2201 	nfs_fs_proc_net_exit(net);
2202 	nfs_clients_exit(net);
2203 }
2204 
2205 static struct pernet_operations nfs_net_ops = {
2206 	.init = nfs_net_init,
2207 	.exit = nfs_net_exit,
2208 	.id   = &nfs_net_id,
2209 	.size = sizeof(struct nfs_net),
2210 };
2211 
2212 /*
2213  * Initialize NFS
2214  */
2215 static int __init init_nfs_fs(void)
2216 {
2217 	int err;
2218 
2219 	err = nfs_sysfs_init();
2220 	if (err < 0)
2221 		goto out10;
2222 
2223 	err = register_pernet_subsys(&nfs_net_ops);
2224 	if (err < 0)
2225 		goto out9;
2226 
2227 	err = nfs_fscache_register();
2228 	if (err < 0)
2229 		goto out8;
2230 
2231 	err = nfsiod_start();
2232 	if (err)
2233 		goto out7;
2234 
2235 	err = nfs_fs_proc_init();
2236 	if (err)
2237 		goto out6;
2238 
2239 	err = nfs_init_nfspagecache();
2240 	if (err)
2241 		goto out5;
2242 
2243 	err = nfs_init_inodecache();
2244 	if (err)
2245 		goto out4;
2246 
2247 	err = nfs_init_readpagecache();
2248 	if (err)
2249 		goto out3;
2250 
2251 	err = nfs_init_writepagecache();
2252 	if (err)
2253 		goto out2;
2254 
2255 	err = nfs_init_directcache();
2256 	if (err)
2257 		goto out1;
2258 
2259 	rpc_proc_register(&init_net, &nfs_rpcstat);
2260 
2261 	err = register_nfs_fs();
2262 	if (err)
2263 		goto out0;
2264 
2265 	return 0;
2266 out0:
2267 	rpc_proc_unregister(&init_net, "nfs");
2268 	nfs_destroy_directcache();
2269 out1:
2270 	nfs_destroy_writepagecache();
2271 out2:
2272 	nfs_destroy_readpagecache();
2273 out3:
2274 	nfs_destroy_inodecache();
2275 out4:
2276 	nfs_destroy_nfspagecache();
2277 out5:
2278 	nfs_fs_proc_exit();
2279 out6:
2280 	nfsiod_stop();
2281 out7:
2282 	nfs_fscache_unregister();
2283 out8:
2284 	unregister_pernet_subsys(&nfs_net_ops);
2285 out9:
2286 	nfs_sysfs_exit();
2287 out10:
2288 	return err;
2289 }
2290 
2291 static void __exit exit_nfs_fs(void)
2292 {
2293 	nfs_destroy_directcache();
2294 	nfs_destroy_writepagecache();
2295 	nfs_destroy_readpagecache();
2296 	nfs_destroy_inodecache();
2297 	nfs_destroy_nfspagecache();
2298 	nfs_fscache_unregister();
2299 	unregister_pernet_subsys(&nfs_net_ops);
2300 	rpc_proc_unregister(&init_net, "nfs");
2301 	unregister_nfs_fs();
2302 	nfs_fs_proc_exit();
2303 	nfsiod_stop();
2304 	nfs_sysfs_exit();
2305 }
2306 
2307 /* Not quite true; I just maintain it */
2308 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
2309 MODULE_LICENSE("GPL");
2310 module_param(enable_ino64, bool, 0644);
2311 
2312 module_init(init_nfs_fs)
2313 module_exit(exit_nfs_fs)
2314