xref: /linux/fs/nfs/inode.c (revision 988b0c541ed8b1c633c4d4df7169010635942e18)
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/vfs.h>
36 #include <linux/inet.h>
37 #include <linux/nfs_xdr.h>
38 #include <linux/slab.h>
39 #include <linux/compat.h>
40 #include <linux/freezer.h>
41 
42 #include <asm/uaccess.h>
43 
44 #include "nfs4_fs.h"
45 #include "callback.h"
46 #include "delegation.h"
47 #include "iostat.h"
48 #include "internal.h"
49 #include "fscache.h"
50 #include "pnfs.h"
51 #include "nfs.h"
52 #include "netns.h"
53 
54 #include "nfstrace.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_unsafe();
83 	return 0;
84 }
85 EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
86 
87 /**
88  * nfs_compat_user_ino64 - returns the user-visible inode number
89  * @fileid: 64-bit fileid
90  *
91  * This function returns a 32-bit inode number if the boot parameter
92  * nfs.enable_ino64 is zero.
93  */
94 u64 nfs_compat_user_ino64(u64 fileid)
95 {
96 #ifdef CONFIG_COMPAT
97 	compat_ulong_t ino;
98 #else
99 	unsigned long ino;
100 #endif
101 
102 	if (enable_ino64)
103 		return fileid;
104 	ino = fileid;
105 	if (sizeof(ino) < sizeof(fileid))
106 		ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
107 	return ino;
108 }
109 
110 int nfs_drop_inode(struct inode *inode)
111 {
112 	return NFS_STALE(inode) || generic_drop_inode(inode);
113 }
114 EXPORT_SYMBOL_GPL(nfs_drop_inode);
115 
116 void nfs_clear_inode(struct inode *inode)
117 {
118 	/*
119 	 * The following should never happen...
120 	 */
121 	WARN_ON_ONCE(nfs_have_writebacks(inode));
122 	WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files));
123 	nfs_zap_acl_cache(inode);
124 	nfs_access_zap_cache(inode);
125 	nfs_fscache_clear_inode(inode);
126 }
127 EXPORT_SYMBOL_GPL(nfs_clear_inode);
128 
129 void nfs_evict_inode(struct inode *inode)
130 {
131 	truncate_inode_pages_final(&inode->i_data);
132 	clear_inode(inode);
133 	nfs_clear_inode(inode);
134 }
135 
136 /**
137  * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
138  */
139 int nfs_sync_mapping(struct address_space *mapping)
140 {
141 	int ret = 0;
142 
143 	if (mapping->nrpages != 0) {
144 		unmap_mapping_range(mapping, 0, 0, 0);
145 		ret = nfs_wb_all(mapping->host);
146 	}
147 	return ret;
148 }
149 
150 static void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
151 {
152 	struct nfs_inode *nfsi = NFS_I(inode);
153 
154 	if (inode->i_mapping->nrpages == 0)
155 		flags &= ~NFS_INO_INVALID_DATA;
156 	nfsi->cache_validity |= flags;
157 	if (flags & NFS_INO_INVALID_DATA)
158 		nfs_fscache_invalidate(inode);
159 }
160 
161 /*
162  * Invalidate the local caches
163  */
164 static void nfs_zap_caches_locked(struct inode *inode)
165 {
166 	struct nfs_inode *nfsi = NFS_I(inode);
167 	int mode = inode->i_mode;
168 
169 	nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
170 
171 	nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
172 	nfsi->attrtimeo_timestamp = jiffies;
173 
174 	memset(NFS_I(inode)->cookieverf, 0, sizeof(NFS_I(inode)->cookieverf));
175 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
176 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
177 					| NFS_INO_INVALID_DATA
178 					| NFS_INO_INVALID_ACCESS
179 					| NFS_INO_INVALID_ACL
180 					| NFS_INO_REVAL_PAGECACHE);
181 	} else
182 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
183 					| NFS_INO_INVALID_ACCESS
184 					| NFS_INO_INVALID_ACL
185 					| NFS_INO_REVAL_PAGECACHE);
186 	nfs_zap_label_cache_locked(nfsi);
187 }
188 
189 void nfs_zap_caches(struct inode *inode)
190 {
191 	spin_lock(&inode->i_lock);
192 	nfs_zap_caches_locked(inode);
193 	spin_unlock(&inode->i_lock);
194 }
195 
196 void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
197 {
198 	if (mapping->nrpages != 0) {
199 		spin_lock(&inode->i_lock);
200 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
201 		spin_unlock(&inode->i_lock);
202 	}
203 }
204 
205 void nfs_zap_acl_cache(struct inode *inode)
206 {
207 	void (*clear_acl_cache)(struct inode *);
208 
209 	clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
210 	if (clear_acl_cache != NULL)
211 		clear_acl_cache(inode);
212 	spin_lock(&inode->i_lock);
213 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
214 	spin_unlock(&inode->i_lock);
215 }
216 EXPORT_SYMBOL_GPL(nfs_zap_acl_cache);
217 
218 void nfs_invalidate_atime(struct inode *inode)
219 {
220 	spin_lock(&inode->i_lock);
221 	nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
222 	spin_unlock(&inode->i_lock);
223 }
224 EXPORT_SYMBOL_GPL(nfs_invalidate_atime);
225 
226 /*
227  * Invalidate, but do not unhash, the inode.
228  * NB: must be called with inode->i_lock held!
229  */
230 static void nfs_invalidate_inode(struct inode *inode)
231 {
232 	set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
233 	nfs_zap_caches_locked(inode);
234 }
235 
236 struct nfs_find_desc {
237 	struct nfs_fh		*fh;
238 	struct nfs_fattr	*fattr;
239 };
240 
241 /*
242  * In NFSv3 we can have 64bit inode numbers. In order to support
243  * this, and re-exported directories (also seen in NFSv2)
244  * we are forced to allow 2 different inodes to have the same
245  * i_ino.
246  */
247 static int
248 nfs_find_actor(struct inode *inode, void *opaque)
249 {
250 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
251 	struct nfs_fh		*fh = desc->fh;
252 	struct nfs_fattr	*fattr = desc->fattr;
253 
254 	if (NFS_FILEID(inode) != fattr->fileid)
255 		return 0;
256 	if ((S_IFMT & inode->i_mode) != (S_IFMT & fattr->mode))
257 		return 0;
258 	if (nfs_compare_fh(NFS_FH(inode), fh))
259 		return 0;
260 	if (is_bad_inode(inode) || NFS_STALE(inode))
261 		return 0;
262 	return 1;
263 }
264 
265 static int
266 nfs_init_locked(struct inode *inode, void *opaque)
267 {
268 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
269 	struct nfs_fattr	*fattr = desc->fattr;
270 
271 	set_nfs_fileid(inode, fattr->fileid);
272 	nfs_copy_fh(NFS_FH(inode), desc->fh);
273 	return 0;
274 }
275 
276 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
277 static void nfs_clear_label_invalid(struct inode *inode)
278 {
279 	spin_lock(&inode->i_lock);
280 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_LABEL;
281 	spin_unlock(&inode->i_lock);
282 }
283 
284 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
285 					struct nfs4_label *label)
286 {
287 	int error;
288 
289 	if (label == NULL)
290 		return;
291 
292 	if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
293 		error = security_inode_notifysecctx(inode, label->label,
294 				label->len);
295 		if (error)
296 			printk(KERN_ERR "%s() %s %d "
297 					"security_inode_notifysecctx() %d\n",
298 					__func__,
299 					(char *)label->label,
300 					label->len, error);
301 		nfs_clear_label_invalid(inode);
302 	}
303 }
304 
305 struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
306 {
307 	struct nfs4_label *label = NULL;
308 	int minor_version = server->nfs_client->cl_minorversion;
309 
310 	if (minor_version < 2)
311 		return label;
312 
313 	if (!(server->caps & NFS_CAP_SECURITY_LABEL))
314 		return label;
315 
316 	label = kzalloc(sizeof(struct nfs4_label), flags);
317 	if (label == NULL)
318 		return ERR_PTR(-ENOMEM);
319 
320 	label->label = kzalloc(NFS4_MAXLABELLEN, flags);
321 	if (label->label == NULL) {
322 		kfree(label);
323 		return ERR_PTR(-ENOMEM);
324 	}
325 	label->len = NFS4_MAXLABELLEN;
326 
327 	return label;
328 }
329 EXPORT_SYMBOL_GPL(nfs4_label_alloc);
330 #else
331 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
332 					struct nfs4_label *label)
333 {
334 }
335 #endif
336 EXPORT_SYMBOL_GPL(nfs_setsecurity);
337 
338 /*
339  * This is our front-end to iget that looks up inodes by file handle
340  * instead of inode number.
341  */
342 struct inode *
343 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, struct nfs4_label *label)
344 {
345 	struct nfs_find_desc desc = {
346 		.fh	= fh,
347 		.fattr	= fattr
348 	};
349 	struct inode *inode = ERR_PTR(-ENOENT);
350 	unsigned long hash;
351 
352 	nfs_attr_check_mountpoint(sb, fattr);
353 
354 	if (((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0) &&
355 	    !nfs_attr_use_mounted_on_fileid(fattr))
356 		goto out_no_inode;
357 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
358 		goto out_no_inode;
359 
360 	hash = nfs_fattr_to_ino_t(fattr);
361 
362 	inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
363 	if (inode == NULL) {
364 		inode = ERR_PTR(-ENOMEM);
365 		goto out_no_inode;
366 	}
367 
368 	if (inode->i_state & I_NEW) {
369 		struct nfs_inode *nfsi = NFS_I(inode);
370 		unsigned long now = jiffies;
371 
372 		/* We set i_ino for the few things that still rely on it,
373 		 * such as stat(2) */
374 		inode->i_ino = hash;
375 
376 		/* We can't support update_atime(), since the server will reset it */
377 		inode->i_flags |= S_NOATIME|S_NOCMTIME;
378 		inode->i_mode = fattr->mode;
379 		if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
380 				&& nfs_server_capable(inode, NFS_CAP_MODE))
381 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
382 		/* Why so? Because we want revalidate for devices/FIFOs, and
383 		 * that's precisely what we have in nfs_file_inode_operations.
384 		 */
385 		inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
386 		if (S_ISREG(inode->i_mode)) {
387 			inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
388 			inode->i_data.a_ops = &nfs_file_aops;
389 			inode->i_data.backing_dev_info = &NFS_SB(sb)->backing_dev_info;
390 		} else if (S_ISDIR(inode->i_mode)) {
391 			inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
392 			inode->i_fop = &nfs_dir_operations;
393 			inode->i_data.a_ops = &nfs_dir_aops;
394 			/* Deal with crossing mountpoints */
395 			if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
396 					fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
397 				if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
398 					inode->i_op = &nfs_referral_inode_operations;
399 				else
400 					inode->i_op = &nfs_mountpoint_inode_operations;
401 				inode->i_fop = NULL;
402 				inode->i_flags |= S_AUTOMOUNT;
403 			}
404 		} else if (S_ISLNK(inode->i_mode))
405 			inode->i_op = &nfs_symlink_inode_operations;
406 		else
407 			init_special_inode(inode, inode->i_mode, fattr->rdev);
408 
409 		memset(&inode->i_atime, 0, sizeof(inode->i_atime));
410 		memset(&inode->i_mtime, 0, sizeof(inode->i_mtime));
411 		memset(&inode->i_ctime, 0, sizeof(inode->i_ctime));
412 		inode->i_version = 0;
413 		inode->i_size = 0;
414 		clear_nlink(inode);
415 		inode->i_uid = make_kuid(&init_user_ns, -2);
416 		inode->i_gid = make_kgid(&init_user_ns, -2);
417 		inode->i_blocks = 0;
418 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
419 		nfsi->write_io = 0;
420 		nfsi->read_io = 0;
421 
422 		nfsi->read_cache_jiffies = fattr->time_start;
423 		nfsi->attr_gencount = fattr->gencount;
424 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
425 			inode->i_atime = fattr->atime;
426 		else if (nfs_server_capable(inode, NFS_CAP_ATIME))
427 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
428 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
429 			inode->i_mtime = fattr->mtime;
430 		else if (nfs_server_capable(inode, NFS_CAP_MTIME))
431 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
432 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
433 			inode->i_ctime = fattr->ctime;
434 		else if (nfs_server_capable(inode, NFS_CAP_CTIME))
435 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
436 		if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
437 			inode->i_version = fattr->change_attr;
438 		else if (nfs_server_capable(inode, NFS_CAP_CHANGE_ATTR))
439 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
440 		if (fattr->valid & NFS_ATTR_FATTR_SIZE)
441 			inode->i_size = nfs_size_to_loff_t(fattr->size);
442 		else
443 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
444 				| NFS_INO_REVAL_PAGECACHE);
445 		if (fattr->valid & NFS_ATTR_FATTR_NLINK)
446 			set_nlink(inode, fattr->nlink);
447 		else if (nfs_server_capable(inode, NFS_CAP_NLINK))
448 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
449 		if (fattr->valid & NFS_ATTR_FATTR_OWNER)
450 			inode->i_uid = fattr->uid;
451 		else if (nfs_server_capable(inode, NFS_CAP_OWNER))
452 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
453 		if (fattr->valid & NFS_ATTR_FATTR_GROUP)
454 			inode->i_gid = fattr->gid;
455 		else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
456 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
457 		if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
458 			inode->i_blocks = fattr->du.nfs2.blocks;
459 		if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
460 			/*
461 			 * report the blocks in 512byte units
462 			 */
463 			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
464 		}
465 
466 		nfs_setsecurity(inode, fattr, label);
467 
468 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
469 		nfsi->attrtimeo_timestamp = now;
470 		nfsi->access_cache = RB_ROOT;
471 
472 		nfs_fscache_init_inode(inode);
473 
474 		unlock_new_inode(inode);
475 	} else
476 		nfs_refresh_inode(inode, fattr);
477 	dprintk("NFS: nfs_fhget(%s/%Lu fh_crc=0x%08x ct=%d)\n",
478 		inode->i_sb->s_id,
479 		(unsigned long long)NFS_FILEID(inode),
480 		nfs_display_fhandle_hash(fh),
481 		atomic_read(&inode->i_count));
482 
483 out:
484 	return inode;
485 
486 out_no_inode:
487 	dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
488 	goto out;
489 }
490 EXPORT_SYMBOL_GPL(nfs_fhget);
491 
492 #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)
493 
494 int
495 nfs_setattr(struct dentry *dentry, struct iattr *attr)
496 {
497 	struct inode *inode = dentry->d_inode;
498 	struct nfs_fattr *fattr;
499 	int error = -ENOMEM;
500 
501 	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
502 
503 	/* skip mode change if it's just for clearing setuid/setgid */
504 	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
505 		attr->ia_valid &= ~ATTR_MODE;
506 
507 	if (attr->ia_valid & ATTR_SIZE) {
508 		if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
509 			attr->ia_valid &= ~ATTR_SIZE;
510 	}
511 
512 	/* Optimization: if the end result is no change, don't RPC */
513 	attr->ia_valid &= NFS_VALID_ATTRS;
514 	if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
515 		return 0;
516 
517 	trace_nfs_setattr_enter(inode);
518 
519 	/* Write all dirty data */
520 	if (S_ISREG(inode->i_mode)) {
521 		nfs_inode_dio_wait(inode);
522 		nfs_wb_all(inode);
523 	}
524 
525 	fattr = nfs_alloc_fattr();
526 	if (fattr == NULL)
527 		goto out;
528 	/*
529 	 * Return any delegations if we're going to change ACLs
530 	 */
531 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
532 		NFS_PROTO(inode)->return_delegation(inode);
533 	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
534 	if (error == 0)
535 		error = nfs_refresh_inode(inode, fattr);
536 	nfs_free_fattr(fattr);
537 out:
538 	trace_nfs_setattr_exit(inode, error);
539 	return error;
540 }
541 EXPORT_SYMBOL_GPL(nfs_setattr);
542 
543 /**
544  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
545  * @inode: inode of the file used
546  * @offset: file offset to start truncating
547  *
548  * This is a copy of the common vmtruncate, but with the locking
549  * corrected to take into account the fact that NFS requires
550  * inode->i_size to be updated under the inode->i_lock.
551  */
552 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
553 {
554 	int err;
555 
556 	err = inode_newsize_ok(inode, offset);
557 	if (err)
558 		goto out;
559 
560 	spin_lock(&inode->i_lock);
561 	i_size_write(inode, offset);
562 	/* Optimisation */
563 	if (offset == 0)
564 		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA;
565 	spin_unlock(&inode->i_lock);
566 
567 	truncate_pagecache(inode, offset);
568 out:
569 	return err;
570 }
571 
572 /**
573  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
574  * @inode: pointer to struct inode
575  * @attr: pointer to struct iattr
576  *
577  * Note: we do this in the *proc.c in order to ensure that
578  *       it works for things like exclusive creates too.
579  */
580 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
581 {
582 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
583 		spin_lock(&inode->i_lock);
584 		if ((attr->ia_valid & ATTR_MODE) != 0) {
585 			int mode = attr->ia_mode & S_IALLUGO;
586 			mode |= inode->i_mode & ~S_IALLUGO;
587 			inode->i_mode = mode;
588 		}
589 		if ((attr->ia_valid & ATTR_UID) != 0)
590 			inode->i_uid = attr->ia_uid;
591 		if ((attr->ia_valid & ATTR_GID) != 0)
592 			inode->i_gid = attr->ia_gid;
593 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS
594 				| NFS_INO_INVALID_ACL);
595 		spin_unlock(&inode->i_lock);
596 	}
597 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
598 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
599 		nfs_vmtruncate(inode, attr->ia_size);
600 	}
601 }
602 EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
603 
604 static void nfs_request_parent_use_readdirplus(struct dentry *dentry)
605 {
606 	struct dentry *parent;
607 
608 	parent = dget_parent(dentry);
609 	nfs_force_use_readdirplus(parent->d_inode);
610 	dput(parent);
611 }
612 
613 static bool nfs_need_revalidate_inode(struct inode *inode)
614 {
615 	if (NFS_I(inode)->cache_validity &
616 			(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
617 		return true;
618 	if (nfs_attribute_cache_expired(inode))
619 		return true;
620 	return false;
621 }
622 
623 int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
624 {
625 	struct inode *inode = dentry->d_inode;
626 	int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
627 	int err;
628 
629 	trace_nfs_getattr_enter(inode);
630 	/* Flush out writes to the server in order to update c/mtime.  */
631 	if (S_ISREG(inode->i_mode)) {
632 		nfs_inode_dio_wait(inode);
633 		err = filemap_write_and_wait(inode->i_mapping);
634 		if (err)
635 			goto out;
636 	}
637 
638 	/*
639 	 * We may force a getattr if the user cares about atime.
640 	 *
641 	 * Note that we only have to check the vfsmount flags here:
642 	 *  - NFS always sets S_NOATIME by so checking it would give a
643 	 *    bogus result
644 	 *  - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
645 	 *    no point in checking those.
646 	 */
647  	if ((mnt->mnt_flags & MNT_NOATIME) ||
648  	    ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
649 		need_atime = 0;
650 
651 	if (need_atime || nfs_need_revalidate_inode(inode)) {
652 		struct nfs_server *server = NFS_SERVER(inode);
653 
654 		if (server->caps & NFS_CAP_READDIRPLUS)
655 			nfs_request_parent_use_readdirplus(dentry);
656 		err = __nfs_revalidate_inode(server, inode);
657 	}
658 	if (!err) {
659 		generic_fillattr(inode, stat);
660 		stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
661 	}
662 out:
663 	trace_nfs_getattr_exit(inode, err);
664 	return err;
665 }
666 EXPORT_SYMBOL_GPL(nfs_getattr);
667 
668 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
669 {
670 	atomic_set(&l_ctx->count, 1);
671 	l_ctx->lockowner.l_owner = current->files;
672 	l_ctx->lockowner.l_pid = current->tgid;
673 	INIT_LIST_HEAD(&l_ctx->list);
674 	nfs_iocounter_init(&l_ctx->io_count);
675 }
676 
677 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
678 {
679 	struct nfs_lock_context *head = &ctx->lock_context;
680 	struct nfs_lock_context *pos = head;
681 
682 	do {
683 		if (pos->lockowner.l_owner != current->files)
684 			continue;
685 		if (pos->lockowner.l_pid != current->tgid)
686 			continue;
687 		atomic_inc(&pos->count);
688 		return pos;
689 	} while ((pos = list_entry(pos->list.next, typeof(*pos), list)) != head);
690 	return NULL;
691 }
692 
693 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
694 {
695 	struct nfs_lock_context *res, *new = NULL;
696 	struct inode *inode = ctx->dentry->d_inode;
697 
698 	spin_lock(&inode->i_lock);
699 	res = __nfs_find_lock_context(ctx);
700 	if (res == NULL) {
701 		spin_unlock(&inode->i_lock);
702 		new = kmalloc(sizeof(*new), GFP_KERNEL);
703 		if (new == NULL)
704 			return ERR_PTR(-ENOMEM);
705 		nfs_init_lock_context(new);
706 		spin_lock(&inode->i_lock);
707 		res = __nfs_find_lock_context(ctx);
708 		if (res == NULL) {
709 			list_add_tail(&new->list, &ctx->lock_context.list);
710 			new->open_context = ctx;
711 			res = new;
712 			new = NULL;
713 		}
714 	}
715 	spin_unlock(&inode->i_lock);
716 	kfree(new);
717 	return res;
718 }
719 
720 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
721 {
722 	struct nfs_open_context *ctx = l_ctx->open_context;
723 	struct inode *inode = ctx->dentry->d_inode;
724 
725 	if (!atomic_dec_and_lock(&l_ctx->count, &inode->i_lock))
726 		return;
727 	list_del(&l_ctx->list);
728 	spin_unlock(&inode->i_lock);
729 	kfree(l_ctx);
730 }
731 
732 /**
733  * nfs_close_context - Common close_context() routine NFSv2/v3
734  * @ctx: pointer to context
735  * @is_sync: is this a synchronous close
736  *
737  * always ensure that the attributes are up to date if we're mounted
738  * with close-to-open semantics
739  */
740 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
741 {
742 	struct inode *inode;
743 	struct nfs_server *server;
744 
745 	if (!(ctx->mode & FMODE_WRITE))
746 		return;
747 	if (!is_sync)
748 		return;
749 	inode = ctx->dentry->d_inode;
750 	if (!list_empty(&NFS_I(inode)->open_files))
751 		return;
752 	server = NFS_SERVER(inode);
753 	if (server->flags & NFS_MOUNT_NOCTO)
754 		return;
755 	nfs_revalidate_inode(server, inode);
756 }
757 EXPORT_SYMBOL_GPL(nfs_close_context);
758 
759 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode)
760 {
761 	struct nfs_open_context *ctx;
762 	struct rpc_cred *cred = rpc_lookup_cred();
763 	if (IS_ERR(cred))
764 		return ERR_CAST(cred);
765 
766 	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
767 	if (!ctx) {
768 		put_rpccred(cred);
769 		return ERR_PTR(-ENOMEM);
770 	}
771 	nfs_sb_active(dentry->d_sb);
772 	ctx->dentry = dget(dentry);
773 	ctx->cred = cred;
774 	ctx->state = NULL;
775 	ctx->mode = f_mode;
776 	ctx->flags = 0;
777 	ctx->error = 0;
778 	nfs_init_lock_context(&ctx->lock_context);
779 	ctx->lock_context.open_context = ctx;
780 	INIT_LIST_HEAD(&ctx->list);
781 	ctx->mdsthreshold = NULL;
782 	return ctx;
783 }
784 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
785 
786 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
787 {
788 	if (ctx != NULL)
789 		atomic_inc(&ctx->lock_context.count);
790 	return ctx;
791 }
792 EXPORT_SYMBOL_GPL(get_nfs_open_context);
793 
794 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
795 {
796 	struct inode *inode = ctx->dentry->d_inode;
797 	struct super_block *sb = ctx->dentry->d_sb;
798 
799 	if (!list_empty(&ctx->list)) {
800 		if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
801 			return;
802 		list_del(&ctx->list);
803 		spin_unlock(&inode->i_lock);
804 	} else if (!atomic_dec_and_test(&ctx->lock_context.count))
805 		return;
806 	if (inode != NULL)
807 		NFS_PROTO(inode)->close_context(ctx, is_sync);
808 	if (ctx->cred != NULL)
809 		put_rpccred(ctx->cred);
810 	dput(ctx->dentry);
811 	nfs_sb_deactive(sb);
812 	kfree(ctx->mdsthreshold);
813 	kfree(ctx);
814 }
815 
816 void put_nfs_open_context(struct nfs_open_context *ctx)
817 {
818 	__put_nfs_open_context(ctx, 0);
819 }
820 EXPORT_SYMBOL_GPL(put_nfs_open_context);
821 
822 /*
823  * Ensure that mmap has a recent RPC credential for use when writing out
824  * shared pages
825  */
826 void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
827 {
828 	struct inode *inode = ctx->dentry->d_inode;
829 	struct nfs_inode *nfsi = NFS_I(inode);
830 
831 	spin_lock(&inode->i_lock);
832 	list_add(&ctx->list, &nfsi->open_files);
833 	spin_unlock(&inode->i_lock);
834 }
835 EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
836 
837 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
838 {
839 	filp->private_data = get_nfs_open_context(ctx);
840 	if (list_empty(&ctx->list))
841 		nfs_inode_attach_open_context(ctx);
842 }
843 EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
844 
845 /*
846  * Given an inode, search for an open context with the desired characteristics
847  */
848 struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode)
849 {
850 	struct nfs_inode *nfsi = NFS_I(inode);
851 	struct nfs_open_context *pos, *ctx = NULL;
852 
853 	spin_lock(&inode->i_lock);
854 	list_for_each_entry(pos, &nfsi->open_files, list) {
855 		if (cred != NULL && pos->cred != cred)
856 			continue;
857 		if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
858 			continue;
859 		ctx = get_nfs_open_context(pos);
860 		break;
861 	}
862 	spin_unlock(&inode->i_lock);
863 	return ctx;
864 }
865 
866 static void nfs_file_clear_open_context(struct file *filp)
867 {
868 	struct nfs_open_context *ctx = nfs_file_open_context(filp);
869 
870 	if (ctx) {
871 		struct inode *inode = ctx->dentry->d_inode;
872 
873 		filp->private_data = NULL;
874 		spin_lock(&inode->i_lock);
875 		list_move_tail(&ctx->list, &NFS_I(inode)->open_files);
876 		spin_unlock(&inode->i_lock);
877 		__put_nfs_open_context(ctx, filp->f_flags & O_DIRECT ? 0 : 1);
878 	}
879 }
880 
881 /*
882  * These allocate and release file read/write context information.
883  */
884 int nfs_open(struct inode *inode, struct file *filp)
885 {
886 	struct nfs_open_context *ctx;
887 
888 	ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
889 	if (IS_ERR(ctx))
890 		return PTR_ERR(ctx);
891 	nfs_file_set_open_context(filp, ctx);
892 	put_nfs_open_context(ctx);
893 	nfs_fscache_open_file(inode, filp);
894 	return 0;
895 }
896 
897 int nfs_release(struct inode *inode, struct file *filp)
898 {
899 	nfs_file_clear_open_context(filp);
900 	return 0;
901 }
902 
903 /*
904  * This function is called whenever some part of NFS notices that
905  * the cached attributes have to be refreshed.
906  */
907 int
908 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
909 {
910 	int		 status = -ESTALE;
911 	struct nfs4_label *label = NULL;
912 	struct nfs_fattr *fattr = NULL;
913 	struct nfs_inode *nfsi = NFS_I(inode);
914 
915 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Lu)\n",
916 		inode->i_sb->s_id, (unsigned long long)NFS_FILEID(inode));
917 
918 	trace_nfs_revalidate_inode_enter(inode);
919 
920 	if (is_bad_inode(inode))
921 		goto out;
922 	if (NFS_STALE(inode))
923 		goto out;
924 
925 	status = -ENOMEM;
926 	fattr = nfs_alloc_fattr();
927 	if (fattr == NULL)
928 		goto out;
929 
930 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
931 
932 	label = nfs4_label_alloc(NFS_SERVER(inode), GFP_KERNEL);
933 	if (IS_ERR(label)) {
934 		status = PTR_ERR(label);
935 		goto out;
936 	}
937 
938 	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr, label);
939 	if (status != 0) {
940 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) getattr failed, error=%d\n",
941 			 inode->i_sb->s_id,
942 			 (unsigned long long)NFS_FILEID(inode), status);
943 		if (status == -ESTALE) {
944 			nfs_zap_caches(inode);
945 			if (!S_ISDIR(inode->i_mode))
946 				set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
947 		}
948 		goto err_out;
949 	}
950 
951 	status = nfs_refresh_inode(inode, fattr);
952 	if (status) {
953 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) refresh failed, error=%d\n",
954 			 inode->i_sb->s_id,
955 			 (unsigned long long)NFS_FILEID(inode), status);
956 		goto err_out;
957 	}
958 
959 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
960 		nfs_zap_acl_cache(inode);
961 
962 	nfs_setsecurity(inode, fattr, label);
963 
964 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) revalidation complete\n",
965 		inode->i_sb->s_id,
966 		(unsigned long long)NFS_FILEID(inode));
967 
968 err_out:
969 	nfs4_label_free(label);
970 out:
971 	nfs_free_fattr(fattr);
972 	trace_nfs_revalidate_inode_exit(inode, status);
973 	return status;
974 }
975 
976 int nfs_attribute_timeout(struct inode *inode)
977 {
978 	struct nfs_inode *nfsi = NFS_I(inode);
979 
980 	return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
981 }
982 
983 int nfs_attribute_cache_expired(struct inode *inode)
984 {
985 	if (nfs_have_delegated_attributes(inode))
986 		return 0;
987 	return nfs_attribute_timeout(inode);
988 }
989 
990 /**
991  * nfs_revalidate_inode - Revalidate the inode attributes
992  * @server - pointer to nfs_server struct
993  * @inode - pointer to inode struct
994  *
995  * Updates inode attribute information by retrieving the data from the server.
996  */
997 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
998 {
999 	if (!nfs_need_revalidate_inode(inode))
1000 		return NFS_STALE(inode) ? -ESTALE : 0;
1001 	return __nfs_revalidate_inode(server, inode);
1002 }
1003 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
1004 
1005 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
1006 {
1007 	struct nfs_inode *nfsi = NFS_I(inode);
1008 	int ret;
1009 
1010 	if (mapping->nrpages != 0) {
1011 		if (S_ISREG(inode->i_mode)) {
1012 			ret = nfs_sync_mapping(mapping);
1013 			if (ret < 0)
1014 				return ret;
1015 		}
1016 		ret = invalidate_inode_pages2(mapping);
1017 		if (ret < 0)
1018 			return ret;
1019 	}
1020 	if (S_ISDIR(inode->i_mode)) {
1021 		spin_lock(&inode->i_lock);
1022 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
1023 		spin_unlock(&inode->i_lock);
1024 	}
1025 	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
1026 	nfs_fscache_wait_on_invalidate(inode);
1027 
1028 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
1029 			inode->i_sb->s_id,
1030 			(unsigned long long)NFS_FILEID(inode));
1031 	return 0;
1032 }
1033 
1034 static bool nfs_mapping_need_revalidate_inode(struct inode *inode)
1035 {
1036 	if (nfs_have_delegated_attributes(inode))
1037 		return false;
1038 	return (NFS_I(inode)->cache_validity & NFS_INO_REVAL_PAGECACHE)
1039 		|| nfs_attribute_timeout(inode)
1040 		|| NFS_STALE(inode);
1041 }
1042 
1043 /**
1044  * nfs_revalidate_mapping - Revalidate the pagecache
1045  * @inode - pointer to host inode
1046  * @mapping - pointer to mapping
1047  */
1048 int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
1049 {
1050 	struct nfs_inode *nfsi = NFS_I(inode);
1051 	unsigned long *bitlock = &nfsi->flags;
1052 	int ret = 0;
1053 
1054 	/* swapfiles are not supposed to be shared. */
1055 	if (IS_SWAPFILE(inode))
1056 		goto out;
1057 
1058 	if (nfs_mapping_need_revalidate_inode(inode)) {
1059 		ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1060 		if (ret < 0)
1061 			goto out;
1062 	}
1063 
1064 	/*
1065 	 * We must clear NFS_INO_INVALID_DATA first to ensure that
1066 	 * invalidations that come in while we're shooting down the mappings
1067 	 * are respected. But, that leaves a race window where one revalidator
1068 	 * can clear the flag, and then another checks it before the mapping
1069 	 * gets invalidated. Fix that by serializing access to this part of
1070 	 * the function.
1071 	 *
1072 	 * At the same time, we need to allow other tasks to see whether we
1073 	 * might be in the middle of invalidating the pages, so we only set
1074 	 * the bit lock here if it looks like we're going to be doing that.
1075 	 */
1076 	for (;;) {
1077 		ret = wait_on_bit(bitlock, NFS_INO_INVALIDATING,
1078 				  nfs_wait_bit_killable, TASK_KILLABLE);
1079 		if (ret)
1080 			goto out;
1081 		spin_lock(&inode->i_lock);
1082 		if (test_bit(NFS_INO_INVALIDATING, bitlock)) {
1083 			spin_unlock(&inode->i_lock);
1084 			continue;
1085 		}
1086 		if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1087 			break;
1088 		spin_unlock(&inode->i_lock);
1089 		goto out;
1090 	}
1091 
1092 	set_bit(NFS_INO_INVALIDATING, bitlock);
1093 	smp_wmb();
1094 	nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
1095 	spin_unlock(&inode->i_lock);
1096 	trace_nfs_invalidate_mapping_enter(inode);
1097 	ret = nfs_invalidate_mapping(inode, mapping);
1098 	trace_nfs_invalidate_mapping_exit(inode, ret);
1099 
1100 	clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
1101 	smp_mb__after_atomic();
1102 	wake_up_bit(bitlock, NFS_INO_INVALIDATING);
1103 out:
1104 	return ret;
1105 }
1106 
1107 static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1108 {
1109 	struct nfs_inode *nfsi = NFS_I(inode);
1110 	unsigned long ret = 0;
1111 
1112 	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
1113 			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
1114 			&& inode->i_version == fattr->pre_change_attr) {
1115 		inode->i_version = fattr->change_attr;
1116 		if (S_ISDIR(inode->i_mode))
1117 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1118 		ret |= NFS_INO_INVALID_ATTR;
1119 	}
1120 	/* If we have atomic WCC data, we may update some attributes */
1121 	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
1122 			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
1123 			&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
1124 		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1125 		ret |= NFS_INO_INVALID_ATTR;
1126 	}
1127 
1128 	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
1129 			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
1130 			&& timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
1131 		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1132 		if (S_ISDIR(inode->i_mode))
1133 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1134 		ret |= NFS_INO_INVALID_ATTR;
1135 	}
1136 	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
1137 			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
1138 			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
1139 			&& nfsi->npages == 0) {
1140 		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
1141 		ret |= NFS_INO_INVALID_ATTR;
1142 	}
1143 
1144 	return ret;
1145 }
1146 
1147 /**
1148  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1149  * @inode - pointer to inode
1150  * @fattr - updated attributes
1151  *
1152  * Verifies the attribute cache. If we have just changed the attributes,
1153  * so that fattr carries weak cache consistency data, then it may
1154  * also update the ctime/mtime/change_attribute.
1155  */
1156 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1157 {
1158 	struct nfs_inode *nfsi = NFS_I(inode);
1159 	loff_t cur_size, new_isize;
1160 	unsigned long invalid = 0;
1161 
1162 
1163 	if (nfs_have_delegated_attributes(inode))
1164 		return 0;
1165 	/* Has the inode gone and changed behind our back? */
1166 	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
1167 		return -EIO;
1168 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
1169 		return -EIO;
1170 
1171 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1172 			inode->i_version != fattr->change_attr)
1173 		invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1174 
1175 	/* Verify a few of the more important attributes */
1176 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec_equal(&inode->i_mtime, &fattr->mtime))
1177 		invalid |= NFS_INO_INVALID_ATTR;
1178 
1179 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1180 		cur_size = i_size_read(inode);
1181 		new_isize = nfs_size_to_loff_t(fattr->size);
1182 		if (cur_size != new_isize && nfsi->npages == 0)
1183 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1184 	}
1185 
1186 	/* Have any file permissions changed? */
1187 	if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
1188 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1189 	if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && !uid_eq(inode->i_uid, fattr->uid))
1190 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1191 	if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && !gid_eq(inode->i_gid, fattr->gid))
1192 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1193 
1194 	/* Has the link count changed? */
1195 	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
1196 		invalid |= NFS_INO_INVALID_ATTR;
1197 
1198 	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec_equal(&inode->i_atime, &fattr->atime))
1199 		invalid |= NFS_INO_INVALID_ATIME;
1200 
1201 	if (invalid != 0)
1202 		nfs_set_cache_invalid(inode, invalid);
1203 
1204 	nfsi->read_cache_jiffies = fattr->time_start;
1205 	return 0;
1206 }
1207 
1208 static int nfs_ctime_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1209 {
1210 	if (!(fattr->valid & NFS_ATTR_FATTR_CTIME))
1211 		return 0;
1212 	return timespec_compare(&fattr->ctime, &inode->i_ctime) > 0;
1213 }
1214 
1215 static int nfs_size_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1216 {
1217 	if (!(fattr->valid & NFS_ATTR_FATTR_SIZE))
1218 		return 0;
1219 	return nfs_size_to_loff_t(fattr->size) > i_size_read(inode);
1220 }
1221 
1222 static atomic_long_t nfs_attr_generation_counter;
1223 
1224 static unsigned long nfs_read_attr_generation_counter(void)
1225 {
1226 	return atomic_long_read(&nfs_attr_generation_counter);
1227 }
1228 
1229 unsigned long nfs_inc_attr_generation_counter(void)
1230 {
1231 	return atomic_long_inc_return(&nfs_attr_generation_counter);
1232 }
1233 
1234 void nfs_fattr_init(struct nfs_fattr *fattr)
1235 {
1236 	fattr->valid = 0;
1237 	fattr->time_start = jiffies;
1238 	fattr->gencount = nfs_inc_attr_generation_counter();
1239 	fattr->owner_name = NULL;
1240 	fattr->group_name = NULL;
1241 }
1242 EXPORT_SYMBOL_GPL(nfs_fattr_init);
1243 
1244 struct nfs_fattr *nfs_alloc_fattr(void)
1245 {
1246 	struct nfs_fattr *fattr;
1247 
1248 	fattr = kmalloc(sizeof(*fattr), GFP_NOFS);
1249 	if (fattr != NULL)
1250 		nfs_fattr_init(fattr);
1251 	return fattr;
1252 }
1253 EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
1254 
1255 struct nfs_fh *nfs_alloc_fhandle(void)
1256 {
1257 	struct nfs_fh *fh;
1258 
1259 	fh = kmalloc(sizeof(struct nfs_fh), GFP_NOFS);
1260 	if (fh != NULL)
1261 		fh->size = 0;
1262 	return fh;
1263 }
1264 EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
1265 
1266 #ifdef NFS_DEBUG
1267 /*
1268  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1269  *                             in the same way that wireshark does
1270  *
1271  * @fh: file handle
1272  *
1273  * For debugging only.
1274  */
1275 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1276 {
1277 	/* wireshark uses 32-bit AUTODIN crc and does a bitwise
1278 	 * not on the result */
1279 	return nfs_fhandle_hash(fh);
1280 }
1281 EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
1282 
1283 /*
1284  * _nfs_display_fhandle - display an NFS file handle on the console
1285  *
1286  * @fh: file handle to display
1287  * @caption: display caption
1288  *
1289  * For debugging only.
1290  */
1291 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1292 {
1293 	unsigned short i;
1294 
1295 	if (fh == NULL || fh->size == 0) {
1296 		printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1297 		return;
1298 	}
1299 
1300 	printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1301 	       caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1302 	for (i = 0; i < fh->size; i += 16) {
1303 		__be32 *pos = (__be32 *)&fh->data[i];
1304 
1305 		switch ((fh->size - i - 1) >> 2) {
1306 		case 0:
1307 			printk(KERN_DEFAULT " %08x\n",
1308 				be32_to_cpup(pos));
1309 			break;
1310 		case 1:
1311 			printk(KERN_DEFAULT " %08x %08x\n",
1312 				be32_to_cpup(pos), be32_to_cpup(pos + 1));
1313 			break;
1314 		case 2:
1315 			printk(KERN_DEFAULT " %08x %08x %08x\n",
1316 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1317 				be32_to_cpup(pos + 2));
1318 			break;
1319 		default:
1320 			printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1321 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1322 				be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1323 		}
1324 	}
1325 }
1326 EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
1327 #endif
1328 
1329 /**
1330  * nfs_inode_attrs_need_update - check if the inode attributes need updating
1331  * @inode - pointer to inode
1332  * @fattr - attributes
1333  *
1334  * Attempt to divine whether or not an RPC call reply carrying stale
1335  * attributes got scheduled after another call carrying updated ones.
1336  *
1337  * To do so, the function first assumes that a more recent ctime means
1338  * that the attributes in fattr are newer, however it also attempt to
1339  * catch the case where ctime either didn't change, or went backwards
1340  * (if someone reset the clock on the server) by looking at whether
1341  * or not this RPC call was started after the inode was last updated.
1342  * Note also the check for wraparound of 'attr_gencount'
1343  *
1344  * The function returns 'true' if it thinks the attributes in 'fattr' are
1345  * more recent than the ones cached in the inode.
1346  *
1347  */
1348 static int nfs_inode_attrs_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1349 {
1350 	const struct nfs_inode *nfsi = NFS_I(inode);
1351 
1352 	return ((long)fattr->gencount - (long)nfsi->attr_gencount) > 0 ||
1353 		nfs_ctime_need_update(inode, fattr) ||
1354 		nfs_size_need_update(inode, fattr) ||
1355 		((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
1356 }
1357 
1358 /*
1359  * Don't trust the change_attribute, mtime, ctime or size if
1360  * a pnfs LAYOUTCOMMIT is outstanding
1361  */
1362 static void nfs_inode_attrs_handle_layoutcommit(struct inode *inode,
1363 		struct nfs_fattr *fattr)
1364 {
1365 	if (pnfs_layoutcommit_outstanding(inode))
1366 		fattr->valid &= ~(NFS_ATTR_FATTR_CHANGE |
1367 				NFS_ATTR_FATTR_MTIME |
1368 				NFS_ATTR_FATTR_CTIME |
1369 				NFS_ATTR_FATTR_SIZE);
1370 }
1371 
1372 static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1373 {
1374 	int ret;
1375 
1376 	trace_nfs_refresh_inode_enter(inode);
1377 
1378 	nfs_inode_attrs_handle_layoutcommit(inode, fattr);
1379 
1380 	if (nfs_inode_attrs_need_update(inode, fattr))
1381 		ret = nfs_update_inode(inode, fattr);
1382 	else
1383 		ret = nfs_check_inode_attributes(inode, fattr);
1384 
1385 	trace_nfs_refresh_inode_exit(inode, ret);
1386 	return ret;
1387 }
1388 
1389 /**
1390  * nfs_refresh_inode - try to update the inode attribute cache
1391  * @inode - pointer to inode
1392  * @fattr - updated attributes
1393  *
1394  * Check that an RPC call that returned attributes has not overlapped with
1395  * other recent updates of the inode metadata, then decide whether it is
1396  * safe to do a full update of the inode attributes, or whether just to
1397  * call nfs_check_inode_attributes.
1398  */
1399 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
1400 {
1401 	int status;
1402 
1403 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1404 		return 0;
1405 	spin_lock(&inode->i_lock);
1406 	status = nfs_refresh_inode_locked(inode, fattr);
1407 	spin_unlock(&inode->i_lock);
1408 
1409 	return status;
1410 }
1411 EXPORT_SYMBOL_GPL(nfs_refresh_inode);
1412 
1413 static int nfs_post_op_update_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1414 {
1415 	unsigned long invalid = NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1416 
1417 	if (S_ISDIR(inode->i_mode))
1418 		invalid |= NFS_INO_INVALID_DATA;
1419 	nfs_set_cache_invalid(inode, invalid);
1420 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1421 		return 0;
1422 	return nfs_refresh_inode_locked(inode, fattr);
1423 }
1424 
1425 /**
1426  * nfs_post_op_update_inode - try to update the inode attribute cache
1427  * @inode - pointer to inode
1428  * @fattr - updated attributes
1429  *
1430  * After an operation that has changed the inode metadata, mark the
1431  * attribute cache as being invalid, then try to update it.
1432  *
1433  * NB: if the server didn't return any post op attributes, this
1434  * function will force the retrieval of attributes before the next
1435  * NFS request.  Thus it should be used only for operations that
1436  * are expected to change one or more attributes, to avoid
1437  * unnecessary NFS requests and trips through nfs_update_inode().
1438  */
1439 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1440 {
1441 	int status;
1442 
1443 	spin_lock(&inode->i_lock);
1444 	status = nfs_post_op_update_inode_locked(inode, fattr);
1445 	spin_unlock(&inode->i_lock);
1446 
1447 	return status;
1448 }
1449 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
1450 
1451 /**
1452  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
1453  * @inode - pointer to inode
1454  * @fattr - updated attributes
1455  *
1456  * After an operation that has changed the inode metadata, mark the
1457  * attribute cache as being invalid, then try to update it. Fake up
1458  * weak cache consistency data, if none exist.
1459  *
1460  * This function is mainly designed to be used by the ->write_done() functions.
1461  */
1462 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
1463 {
1464 	int status;
1465 
1466 	spin_lock(&inode->i_lock);
1467 	/* Don't do a WCC update if these attributes are already stale */
1468 	if ((fattr->valid & NFS_ATTR_FATTR) == 0 ||
1469 			!nfs_inode_attrs_need_update(inode, fattr)) {
1470 		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
1471 				| NFS_ATTR_FATTR_PRESIZE
1472 				| NFS_ATTR_FATTR_PREMTIME
1473 				| NFS_ATTR_FATTR_PRECTIME);
1474 		goto out_noforce;
1475 	}
1476 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1477 			(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
1478 		fattr->pre_change_attr = inode->i_version;
1479 		fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
1480 	}
1481 	if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
1482 			(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
1483 		memcpy(&fattr->pre_ctime, &inode->i_ctime, sizeof(fattr->pre_ctime));
1484 		fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
1485 	}
1486 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
1487 			(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
1488 		memcpy(&fattr->pre_mtime, &inode->i_mtime, sizeof(fattr->pre_mtime));
1489 		fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
1490 	}
1491 	if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
1492 			(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
1493 		fattr->pre_size = i_size_read(inode);
1494 		fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
1495 	}
1496 out_noforce:
1497 	status = nfs_post_op_update_inode_locked(inode, fattr);
1498 	spin_unlock(&inode->i_lock);
1499 	return status;
1500 }
1501 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
1502 
1503 /*
1504  * Many nfs protocol calls return the new file attributes after
1505  * an operation.  Here we update the inode to reflect the state
1506  * of the server's inode.
1507  *
1508  * This is a bit tricky because we have to make sure all dirty pages
1509  * have been sent off to the server before calling invalidate_inode_pages.
1510  * To make sure no other process adds more write requests while we try
1511  * our best to flush them, we make them sleep during the attribute refresh.
1512  *
1513  * A very similar scenario holds for the dir cache.
1514  */
1515 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1516 {
1517 	struct nfs_server *server;
1518 	struct nfs_inode *nfsi = NFS_I(inode);
1519 	loff_t cur_isize, new_isize;
1520 	unsigned long invalid = 0;
1521 	unsigned long now = jiffies;
1522 	unsigned long save_cache_validity;
1523 
1524 	dfprintk(VFS, "NFS: %s(%s/%lu fh_crc=0x%08x ct=%d info=0x%x)\n",
1525 			__func__, inode->i_sb->s_id, inode->i_ino,
1526 			nfs_display_fhandle_hash(NFS_FH(inode)),
1527 			atomic_read(&inode->i_count), fattr->valid);
1528 
1529 	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid) {
1530 		printk(KERN_ERR "NFS: server %s error: fileid changed\n"
1531 			"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
1532 			NFS_SERVER(inode)->nfs_client->cl_hostname,
1533 			inode->i_sb->s_id, (long long)nfsi->fileid,
1534 			(long long)fattr->fileid);
1535 		goto out_err;
1536 	}
1537 
1538 	/*
1539 	 * Make sure the inode's type hasn't changed.
1540 	 */
1541 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
1542 		/*
1543 		* Big trouble! The inode has become a different object.
1544 		*/
1545 		printk(KERN_DEBUG "NFS: %s: inode %lu mode changed, %07o to %07o\n",
1546 				__func__, inode->i_ino, inode->i_mode, fattr->mode);
1547 		goto out_err;
1548 	}
1549 
1550 	server = NFS_SERVER(inode);
1551 	/* Update the fsid? */
1552 	if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
1553 			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
1554 			!IS_AUTOMOUNT(inode))
1555 		server->fsid = fattr->fsid;
1556 
1557 	/*
1558 	 * Update the read time so we don't revalidate too often.
1559 	 */
1560 	nfsi->read_cache_jiffies = fattr->time_start;
1561 
1562 	save_cache_validity = nfsi->cache_validity;
1563 	nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
1564 			| NFS_INO_INVALID_ATIME
1565 			| NFS_INO_REVAL_FORCED
1566 			| NFS_INO_REVAL_PAGECACHE);
1567 
1568 	/* Do atomic weak cache consistency updates */
1569 	invalid |= nfs_wcc_update_inode(inode, fattr);
1570 
1571 	/* More cache consistency checks */
1572 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
1573 		if (inode->i_version != fattr->change_attr) {
1574 			dprintk("NFS: change_attr change on server for file %s/%ld\n",
1575 					inode->i_sb->s_id, inode->i_ino);
1576 			invalid |= NFS_INO_INVALID_ATTR
1577 				| NFS_INO_INVALID_DATA
1578 				| NFS_INO_INVALID_ACCESS
1579 				| NFS_INO_INVALID_ACL
1580 				| NFS_INO_REVAL_PAGECACHE;
1581 			if (S_ISDIR(inode->i_mode))
1582 				nfs_force_lookup_revalidate(inode);
1583 			inode->i_version = fattr->change_attr;
1584 		}
1585 	} else if (server->caps & NFS_CAP_CHANGE_ATTR)
1586 		nfsi->cache_validity |= save_cache_validity;
1587 
1588 	if (fattr->valid & NFS_ATTR_FATTR_MTIME) {
1589 		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1590 	} else if (server->caps & NFS_CAP_MTIME)
1591 		nfsi->cache_validity |= save_cache_validity &
1592 				(NFS_INO_INVALID_ATTR
1593 				| NFS_INO_REVAL_FORCED);
1594 
1595 	if (fattr->valid & NFS_ATTR_FATTR_CTIME) {
1596 		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1597 	} else if (server->caps & NFS_CAP_CTIME)
1598 		nfsi->cache_validity |= save_cache_validity &
1599 				(NFS_INO_INVALID_ATTR
1600 				| NFS_INO_REVAL_FORCED);
1601 
1602 	/* Check if our cached file size is stale */
1603 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1604 		new_isize = nfs_size_to_loff_t(fattr->size);
1605 		cur_isize = i_size_read(inode);
1606 		if (new_isize != cur_isize) {
1607 			/* Do we perhaps have any outstanding writes, or has
1608 			 * the file grown beyond our last write? */
1609 			if ((nfsi->npages == 0) || new_isize > cur_isize) {
1610 				i_size_write(inode, new_isize);
1611 				invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
1612 				invalid &= ~NFS_INO_REVAL_PAGECACHE;
1613 			}
1614 			dprintk("NFS: isize change on server for file %s/%ld "
1615 					"(%Ld to %Ld)\n",
1616 					inode->i_sb->s_id,
1617 					inode->i_ino,
1618 					(long long)cur_isize,
1619 					(long long)new_isize);
1620 		}
1621 	} else
1622 		nfsi->cache_validity |= save_cache_validity &
1623 				(NFS_INO_INVALID_ATTR
1624 				| NFS_INO_REVAL_PAGECACHE
1625 				| NFS_INO_REVAL_FORCED);
1626 
1627 
1628 	if (fattr->valid & NFS_ATTR_FATTR_ATIME)
1629 		memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
1630 	else if (server->caps & NFS_CAP_ATIME)
1631 		nfsi->cache_validity |= save_cache_validity &
1632 				(NFS_INO_INVALID_ATIME
1633 				| NFS_INO_REVAL_FORCED);
1634 
1635 	if (fattr->valid & NFS_ATTR_FATTR_MODE) {
1636 		if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
1637 			umode_t newmode = inode->i_mode & S_IFMT;
1638 			newmode |= fattr->mode & S_IALLUGO;
1639 			inode->i_mode = newmode;
1640 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1641 		}
1642 	} else if (server->caps & NFS_CAP_MODE)
1643 		nfsi->cache_validity |= save_cache_validity &
1644 				(NFS_INO_INVALID_ATTR
1645 				| NFS_INO_INVALID_ACCESS
1646 				| NFS_INO_INVALID_ACL
1647 				| NFS_INO_REVAL_FORCED);
1648 
1649 	if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
1650 		if (!uid_eq(inode->i_uid, fattr->uid)) {
1651 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1652 			inode->i_uid = fattr->uid;
1653 		}
1654 	} else if (server->caps & NFS_CAP_OWNER)
1655 		nfsi->cache_validity |= save_cache_validity &
1656 				(NFS_INO_INVALID_ATTR
1657 				| NFS_INO_INVALID_ACCESS
1658 				| NFS_INO_INVALID_ACL
1659 				| NFS_INO_REVAL_FORCED);
1660 
1661 	if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
1662 		if (!gid_eq(inode->i_gid, fattr->gid)) {
1663 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1664 			inode->i_gid = fattr->gid;
1665 		}
1666 	} else if (server->caps & NFS_CAP_OWNER_GROUP)
1667 		nfsi->cache_validity |= save_cache_validity &
1668 				(NFS_INO_INVALID_ATTR
1669 				| NFS_INO_INVALID_ACCESS
1670 				| NFS_INO_INVALID_ACL
1671 				| NFS_INO_REVAL_FORCED);
1672 
1673 	if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
1674 		if (inode->i_nlink != fattr->nlink) {
1675 			invalid |= NFS_INO_INVALID_ATTR;
1676 			if (S_ISDIR(inode->i_mode))
1677 				invalid |= NFS_INO_INVALID_DATA;
1678 			set_nlink(inode, fattr->nlink);
1679 		}
1680 	} else if (server->caps & NFS_CAP_NLINK)
1681 		nfsi->cache_validity |= save_cache_validity &
1682 				(NFS_INO_INVALID_ATTR
1683 				| NFS_INO_REVAL_FORCED);
1684 
1685 	if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
1686 		/*
1687 		 * report the blocks in 512byte units
1688 		 */
1689 		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
1690  	}
1691 	if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
1692 		inode->i_blocks = fattr->du.nfs2.blocks;
1693 
1694 	/* Update attrtimeo value if we're out of the unstable period */
1695 	if (invalid & NFS_INO_INVALID_ATTR) {
1696 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
1697 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
1698 		nfsi->attrtimeo_timestamp = now;
1699 		nfsi->attr_gencount = nfs_inc_attr_generation_counter();
1700 	} else {
1701 		if (!time_in_range_open(now, nfsi->attrtimeo_timestamp, nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
1702 			if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
1703 				nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
1704 			nfsi->attrtimeo_timestamp = now;
1705 		}
1706 	}
1707 	invalid &= ~NFS_INO_INVALID_ATTR;
1708 	/* Don't invalidate the data if we were to blame */
1709 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
1710 				|| S_ISLNK(inode->i_mode)))
1711 		invalid &= ~NFS_INO_INVALID_DATA;
1712 	if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ) ||
1713 			(save_cache_validity & NFS_INO_REVAL_FORCED))
1714 		nfs_set_cache_invalid(inode, invalid);
1715 
1716 	return 0;
1717  out_err:
1718 	/*
1719 	 * No need to worry about unhashing the dentry, as the
1720 	 * lookup validation will know that the inode is bad.
1721 	 * (But we fall through to invalidate the caches.)
1722 	 */
1723 	nfs_invalidate_inode(inode);
1724 	return -ESTALE;
1725 }
1726 
1727 struct inode *nfs_alloc_inode(struct super_block *sb)
1728 {
1729 	struct nfs_inode *nfsi;
1730 	nfsi = (struct nfs_inode *)kmem_cache_alloc(nfs_inode_cachep, GFP_KERNEL);
1731 	if (!nfsi)
1732 		return NULL;
1733 	nfsi->flags = 0UL;
1734 	nfsi->cache_validity = 0UL;
1735 #if IS_ENABLED(CONFIG_NFS_V4)
1736 	nfsi->nfs4_acl = NULL;
1737 #endif /* CONFIG_NFS_V4 */
1738 	return &nfsi->vfs_inode;
1739 }
1740 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
1741 
1742 static void nfs_i_callback(struct rcu_head *head)
1743 {
1744 	struct inode *inode = container_of(head, struct inode, i_rcu);
1745 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
1746 }
1747 
1748 void nfs_destroy_inode(struct inode *inode)
1749 {
1750 	call_rcu(&inode->i_rcu, nfs_i_callback);
1751 }
1752 EXPORT_SYMBOL_GPL(nfs_destroy_inode);
1753 
1754 static inline void nfs4_init_once(struct nfs_inode *nfsi)
1755 {
1756 #if IS_ENABLED(CONFIG_NFS_V4)
1757 	INIT_LIST_HEAD(&nfsi->open_states);
1758 	nfsi->delegation = NULL;
1759 	nfsi->delegation_state = 0;
1760 	init_rwsem(&nfsi->rwsem);
1761 	nfsi->layout = NULL;
1762 #endif
1763 }
1764 
1765 static void init_once(void *foo)
1766 {
1767 	struct nfs_inode *nfsi = (struct nfs_inode *) foo;
1768 
1769 	inode_init_once(&nfsi->vfs_inode);
1770 	INIT_LIST_HEAD(&nfsi->open_files);
1771 	INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
1772 	INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
1773 	INIT_LIST_HEAD(&nfsi->commit_info.list);
1774 	nfsi->npages = 0;
1775 	nfsi->commit_info.ncommit = 0;
1776 	atomic_set(&nfsi->commit_info.rpcs_out, 0);
1777 	atomic_set(&nfsi->silly_count, 1);
1778 	INIT_HLIST_HEAD(&nfsi->silly_list);
1779 	init_waitqueue_head(&nfsi->waitqueue);
1780 	nfs4_init_once(nfsi);
1781 }
1782 
1783 static int __init nfs_init_inodecache(void)
1784 {
1785 	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
1786 					     sizeof(struct nfs_inode),
1787 					     0, (SLAB_RECLAIM_ACCOUNT|
1788 						SLAB_MEM_SPREAD),
1789 					     init_once);
1790 	if (nfs_inode_cachep == NULL)
1791 		return -ENOMEM;
1792 
1793 	return 0;
1794 }
1795 
1796 static void nfs_destroy_inodecache(void)
1797 {
1798 	/*
1799 	 * Make sure all delayed rcu free inodes are flushed before we
1800 	 * destroy cache.
1801 	 */
1802 	rcu_barrier();
1803 	kmem_cache_destroy(nfs_inode_cachep);
1804 }
1805 
1806 struct workqueue_struct *nfsiod_workqueue;
1807 EXPORT_SYMBOL_GPL(nfsiod_workqueue);
1808 
1809 /*
1810  * start up the nfsiod workqueue
1811  */
1812 static int nfsiod_start(void)
1813 {
1814 	struct workqueue_struct *wq;
1815 	dprintk("RPC:       creating workqueue nfsiod\n");
1816 	wq = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM, 0);
1817 	if (wq == NULL)
1818 		return -ENOMEM;
1819 	nfsiod_workqueue = wq;
1820 	return 0;
1821 }
1822 
1823 /*
1824  * Destroy the nfsiod workqueue
1825  */
1826 static void nfsiod_stop(void)
1827 {
1828 	struct workqueue_struct *wq;
1829 
1830 	wq = nfsiod_workqueue;
1831 	if (wq == NULL)
1832 		return;
1833 	nfsiod_workqueue = NULL;
1834 	destroy_workqueue(wq);
1835 }
1836 
1837 int nfs_net_id;
1838 EXPORT_SYMBOL_GPL(nfs_net_id);
1839 
1840 static int nfs_net_init(struct net *net)
1841 {
1842 	nfs_clients_init(net);
1843 	return 0;
1844 }
1845 
1846 static void nfs_net_exit(struct net *net)
1847 {
1848 	nfs_cleanup_cb_ident_idr(net);
1849 }
1850 
1851 static struct pernet_operations nfs_net_ops = {
1852 	.init = nfs_net_init,
1853 	.exit = nfs_net_exit,
1854 	.id   = &nfs_net_id,
1855 	.size = sizeof(struct nfs_net),
1856 };
1857 
1858 /*
1859  * Initialize NFS
1860  */
1861 static int __init init_nfs_fs(void)
1862 {
1863 	int err;
1864 
1865 	err = register_pernet_subsys(&nfs_net_ops);
1866 	if (err < 0)
1867 		goto out9;
1868 
1869 	err = nfs_fscache_register();
1870 	if (err < 0)
1871 		goto out8;
1872 
1873 	err = nfsiod_start();
1874 	if (err)
1875 		goto out7;
1876 
1877 	err = nfs_fs_proc_init();
1878 	if (err)
1879 		goto out6;
1880 
1881 	err = nfs_init_nfspagecache();
1882 	if (err)
1883 		goto out5;
1884 
1885 	err = nfs_init_inodecache();
1886 	if (err)
1887 		goto out4;
1888 
1889 	err = nfs_init_readpagecache();
1890 	if (err)
1891 		goto out3;
1892 
1893 	err = nfs_init_writepagecache();
1894 	if (err)
1895 		goto out2;
1896 
1897 	err = nfs_init_directcache();
1898 	if (err)
1899 		goto out1;
1900 
1901 #ifdef CONFIG_PROC_FS
1902 	rpc_proc_register(&init_net, &nfs_rpcstat);
1903 #endif
1904 	if ((err = register_nfs_fs()) != 0)
1905 		goto out0;
1906 
1907 	return 0;
1908 out0:
1909 #ifdef CONFIG_PROC_FS
1910 	rpc_proc_unregister(&init_net, "nfs");
1911 #endif
1912 	nfs_destroy_directcache();
1913 out1:
1914 	nfs_destroy_writepagecache();
1915 out2:
1916 	nfs_destroy_readpagecache();
1917 out3:
1918 	nfs_destroy_inodecache();
1919 out4:
1920 	nfs_destroy_nfspagecache();
1921 out5:
1922 	nfs_fs_proc_exit();
1923 out6:
1924 	nfsiod_stop();
1925 out7:
1926 	nfs_fscache_unregister();
1927 out8:
1928 	unregister_pernet_subsys(&nfs_net_ops);
1929 out9:
1930 	return err;
1931 }
1932 
1933 static void __exit exit_nfs_fs(void)
1934 {
1935 	nfs_destroy_directcache();
1936 	nfs_destroy_writepagecache();
1937 	nfs_destroy_readpagecache();
1938 	nfs_destroy_inodecache();
1939 	nfs_destroy_nfspagecache();
1940 	nfs_fscache_unregister();
1941 	unregister_pernet_subsys(&nfs_net_ops);
1942 #ifdef CONFIG_PROC_FS
1943 	rpc_proc_unregister(&init_net, "nfs");
1944 #endif
1945 	unregister_nfs_fs();
1946 	nfs_fs_proc_exit();
1947 	nfsiod_stop();
1948 }
1949 
1950 /* Not quite true; I just maintain it */
1951 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
1952 MODULE_LICENSE("GPL");
1953 module_param(enable_ino64, bool, 0644);
1954 
1955 module_init(init_nfs_fs)
1956 module_exit(exit_nfs_fs)
1957