xref: /linux/fs/nfs/inode.c (revision 4d7696f1b05f4aeb586c74868fe3da2731daca4b)
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_release_inode_cookie(inode);
126 }
127 EXPORT_SYMBOL_GPL(nfs_clear_inode);
128 
129 void nfs_evict_inode(struct inode *inode)
130 {
131 	truncate_inode_pages(&inode->i_data, 0);
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 /*
151  * Invalidate the local caches
152  */
153 static void nfs_zap_caches_locked(struct inode *inode)
154 {
155 	struct nfs_inode *nfsi = NFS_I(inode);
156 	int mode = inode->i_mode;
157 
158 	nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
159 
160 	nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
161 	nfsi->attrtimeo_timestamp = jiffies;
162 
163 	memset(NFS_I(inode)->cookieverf, 0, sizeof(NFS_I(inode)->cookieverf));
164 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
165 		nfs_fscache_invalidate(inode);
166 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR
167 					| NFS_INO_INVALID_LABEL
168 					| NFS_INO_INVALID_DATA
169 					| NFS_INO_INVALID_ACCESS
170 					| NFS_INO_INVALID_ACL
171 					| NFS_INO_REVAL_PAGECACHE;
172 	} else
173 		nfsi->cache_validity |= NFS_INO_INVALID_ATTR
174 					| NFS_INO_INVALID_LABEL
175 					| NFS_INO_INVALID_ACCESS
176 					| NFS_INO_INVALID_ACL
177 					| NFS_INO_REVAL_PAGECACHE;
178 }
179 
180 void nfs_zap_caches(struct inode *inode)
181 {
182 	spin_lock(&inode->i_lock);
183 	nfs_zap_caches_locked(inode);
184 	spin_unlock(&inode->i_lock);
185 }
186 
187 void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
188 {
189 	if (mapping->nrpages != 0) {
190 		spin_lock(&inode->i_lock);
191 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
192 		nfs_fscache_invalidate(inode);
193 		spin_unlock(&inode->i_lock);
194 	}
195 }
196 
197 void nfs_zap_acl_cache(struct inode *inode)
198 {
199 	void (*clear_acl_cache)(struct inode *);
200 
201 	clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
202 	if (clear_acl_cache != NULL)
203 		clear_acl_cache(inode);
204 	spin_lock(&inode->i_lock);
205 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
206 	spin_unlock(&inode->i_lock);
207 }
208 EXPORT_SYMBOL_GPL(nfs_zap_acl_cache);
209 
210 void nfs_invalidate_atime(struct inode *inode)
211 {
212 	spin_lock(&inode->i_lock);
213 	NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME;
214 	spin_unlock(&inode->i_lock);
215 }
216 EXPORT_SYMBOL_GPL(nfs_invalidate_atime);
217 
218 /*
219  * Invalidate, but do not unhash, the inode.
220  * NB: must be called with inode->i_lock held!
221  */
222 static void nfs_invalidate_inode(struct inode *inode)
223 {
224 	set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
225 	nfs_zap_caches_locked(inode);
226 }
227 
228 struct nfs_find_desc {
229 	struct nfs_fh		*fh;
230 	struct nfs_fattr	*fattr;
231 };
232 
233 /*
234  * In NFSv3 we can have 64bit inode numbers. In order to support
235  * this, and re-exported directories (also seen in NFSv2)
236  * we are forced to allow 2 different inodes to have the same
237  * i_ino.
238  */
239 static int
240 nfs_find_actor(struct inode *inode, void *opaque)
241 {
242 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
243 	struct nfs_fh		*fh = desc->fh;
244 	struct nfs_fattr	*fattr = desc->fattr;
245 
246 	if (NFS_FILEID(inode) != fattr->fileid)
247 		return 0;
248 	if ((S_IFMT & inode->i_mode) != (S_IFMT & fattr->mode))
249 		return 0;
250 	if (nfs_compare_fh(NFS_FH(inode), fh))
251 		return 0;
252 	if (is_bad_inode(inode) || NFS_STALE(inode))
253 		return 0;
254 	return 1;
255 }
256 
257 static int
258 nfs_init_locked(struct inode *inode, void *opaque)
259 {
260 	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
261 	struct nfs_fattr	*fattr = desc->fattr;
262 
263 	set_nfs_fileid(inode, fattr->fileid);
264 	nfs_copy_fh(NFS_FH(inode), desc->fh);
265 	return 0;
266 }
267 
268 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
269 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
270 					struct nfs4_label *label)
271 {
272 	int error;
273 
274 	if (label == NULL)
275 		return;
276 
277 	if (nfs_server_capable(inode, NFS_CAP_SECURITY_LABEL) == 0)
278 		return;
279 
280 	if (NFS_SERVER(inode)->nfs_client->cl_minorversion < 2)
281 		return;
282 
283 	if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
284 		error = security_inode_notifysecctx(inode, label->label,
285 				label->len);
286 		if (error)
287 			printk(KERN_ERR "%s() %s %d "
288 					"security_inode_notifysecctx() %d\n",
289 					__func__,
290 					(char *)label->label,
291 					label->len, error);
292 	}
293 }
294 
295 struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
296 {
297 	struct nfs4_label *label = NULL;
298 	int minor_version = server->nfs_client->cl_minorversion;
299 
300 	if (minor_version < 2)
301 		return label;
302 
303 	if (!(server->caps & NFS_CAP_SECURITY_LABEL))
304 		return label;
305 
306 	label = kzalloc(sizeof(struct nfs4_label), flags);
307 	if (label == NULL)
308 		return ERR_PTR(-ENOMEM);
309 
310 	label->label = kzalloc(NFS4_MAXLABELLEN, flags);
311 	if (label->label == NULL) {
312 		kfree(label);
313 		return ERR_PTR(-ENOMEM);
314 	}
315 	label->len = NFS4_MAXLABELLEN;
316 
317 	return label;
318 }
319 EXPORT_SYMBOL_GPL(nfs4_label_alloc);
320 #else
321 void inline nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
322 					struct nfs4_label *label)
323 {
324 }
325 #endif
326 EXPORT_SYMBOL_GPL(nfs_setsecurity);
327 
328 /*
329  * This is our front-end to iget that looks up inodes by file handle
330  * instead of inode number.
331  */
332 struct inode *
333 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, struct nfs4_label *label)
334 {
335 	struct nfs_find_desc desc = {
336 		.fh	= fh,
337 		.fattr	= fattr
338 	};
339 	struct inode *inode = ERR_PTR(-ENOENT);
340 	unsigned long hash;
341 
342 	nfs_attr_check_mountpoint(sb, fattr);
343 
344 	if (((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0) &&
345 	    !nfs_attr_use_mounted_on_fileid(fattr))
346 		goto out_no_inode;
347 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
348 		goto out_no_inode;
349 
350 	hash = nfs_fattr_to_ino_t(fattr);
351 
352 	inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
353 	if (inode == NULL) {
354 		inode = ERR_PTR(-ENOMEM);
355 		goto out_no_inode;
356 	}
357 
358 	if (inode->i_state & I_NEW) {
359 		struct nfs_inode *nfsi = NFS_I(inode);
360 		unsigned long now = jiffies;
361 
362 		/* We set i_ino for the few things that still rely on it,
363 		 * such as stat(2) */
364 		inode->i_ino = hash;
365 
366 		/* We can't support update_atime(), since the server will reset it */
367 		inode->i_flags |= S_NOATIME|S_NOCMTIME;
368 		inode->i_mode = fattr->mode;
369 		if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
370 				&& nfs_server_capable(inode, NFS_CAP_MODE))
371 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
372 		/* Why so? Because we want revalidate for devices/FIFOs, and
373 		 * that's precisely what we have in nfs_file_inode_operations.
374 		 */
375 		inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
376 		if (S_ISREG(inode->i_mode)) {
377 			inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
378 			inode->i_data.a_ops = &nfs_file_aops;
379 			inode->i_data.backing_dev_info = &NFS_SB(sb)->backing_dev_info;
380 		} else if (S_ISDIR(inode->i_mode)) {
381 			inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
382 			inode->i_fop = &nfs_dir_operations;
383 			inode->i_data.a_ops = &nfs_dir_aops;
384 			/* Deal with crossing mountpoints */
385 			if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
386 					fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
387 				if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
388 					inode->i_op = &nfs_referral_inode_operations;
389 				else
390 					inode->i_op = &nfs_mountpoint_inode_operations;
391 				inode->i_fop = NULL;
392 				inode->i_flags |= S_AUTOMOUNT;
393 			}
394 		} else if (S_ISLNK(inode->i_mode))
395 			inode->i_op = &nfs_symlink_inode_operations;
396 		else
397 			init_special_inode(inode, inode->i_mode, fattr->rdev);
398 
399 		memset(&inode->i_atime, 0, sizeof(inode->i_atime));
400 		memset(&inode->i_mtime, 0, sizeof(inode->i_mtime));
401 		memset(&inode->i_ctime, 0, sizeof(inode->i_ctime));
402 		inode->i_version = 0;
403 		inode->i_size = 0;
404 		clear_nlink(inode);
405 		inode->i_uid = make_kuid(&init_user_ns, -2);
406 		inode->i_gid = make_kgid(&init_user_ns, -2);
407 		inode->i_blocks = 0;
408 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
409 		nfsi->write_io = 0;
410 		nfsi->read_io = 0;
411 
412 		nfsi->read_cache_jiffies = fattr->time_start;
413 		nfsi->attr_gencount = fattr->gencount;
414 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
415 			inode->i_atime = fattr->atime;
416 		else if (nfs_server_capable(inode, NFS_CAP_ATIME))
417 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
418 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
419 			inode->i_mtime = fattr->mtime;
420 		else if (nfs_server_capable(inode, NFS_CAP_MTIME))
421 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
422 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
423 			inode->i_ctime = fattr->ctime;
424 		else if (nfs_server_capable(inode, NFS_CAP_CTIME))
425 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
426 		if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
427 			inode->i_version = fattr->change_attr;
428 		else if (nfs_server_capable(inode, NFS_CAP_CHANGE_ATTR))
429 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
430 		if (fattr->valid & NFS_ATTR_FATTR_SIZE)
431 			inode->i_size = nfs_size_to_loff_t(fattr->size);
432 		else
433 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
434 				| NFS_INO_REVAL_PAGECACHE;
435 		if (fattr->valid & NFS_ATTR_FATTR_NLINK)
436 			set_nlink(inode, fattr->nlink);
437 		else if (nfs_server_capable(inode, NFS_CAP_NLINK))
438 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
439 		if (fattr->valid & NFS_ATTR_FATTR_OWNER)
440 			inode->i_uid = fattr->uid;
441 		else if (nfs_server_capable(inode, NFS_CAP_OWNER))
442 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
443 		if (fattr->valid & NFS_ATTR_FATTR_GROUP)
444 			inode->i_gid = fattr->gid;
445 		else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
446 			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
447 		if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
448 			inode->i_blocks = fattr->du.nfs2.blocks;
449 		if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
450 			/*
451 			 * report the blocks in 512byte units
452 			 */
453 			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
454 		}
455 
456 		nfs_setsecurity(inode, fattr, label);
457 
458 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
459 		nfsi->attrtimeo_timestamp = now;
460 		nfsi->access_cache = RB_ROOT;
461 
462 		nfs_fscache_init_inode_cookie(inode);
463 
464 		unlock_new_inode(inode);
465 	} else
466 		nfs_refresh_inode(inode, fattr);
467 	dprintk("NFS: nfs_fhget(%s/%Ld fh_crc=0x%08x ct=%d)\n",
468 		inode->i_sb->s_id,
469 		(long long)NFS_FILEID(inode),
470 		nfs_display_fhandle_hash(fh),
471 		atomic_read(&inode->i_count));
472 
473 out:
474 	return inode;
475 
476 out_no_inode:
477 	dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
478 	goto out;
479 }
480 EXPORT_SYMBOL_GPL(nfs_fhget);
481 
482 #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)
483 
484 int
485 nfs_setattr(struct dentry *dentry, struct iattr *attr)
486 {
487 	struct inode *inode = dentry->d_inode;
488 	struct nfs_fattr *fattr;
489 	int error = -ENOMEM;
490 
491 	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
492 
493 	/* skip mode change if it's just for clearing setuid/setgid */
494 	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
495 		attr->ia_valid &= ~ATTR_MODE;
496 
497 	if (attr->ia_valid & ATTR_SIZE) {
498 		if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
499 			attr->ia_valid &= ~ATTR_SIZE;
500 	}
501 
502 	/* Optimization: if the end result is no change, don't RPC */
503 	attr->ia_valid &= NFS_VALID_ATTRS;
504 	if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
505 		return 0;
506 
507 	trace_nfs_setattr_enter(inode);
508 
509 	/* Write all dirty data */
510 	if (S_ISREG(inode->i_mode)) {
511 		nfs_inode_dio_wait(inode);
512 		nfs_wb_all(inode);
513 	}
514 
515 	fattr = nfs_alloc_fattr();
516 	if (fattr == NULL)
517 		goto out;
518 	/*
519 	 * Return any delegations if we're going to change ACLs
520 	 */
521 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
522 		NFS_PROTO(inode)->return_delegation(inode);
523 	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
524 	if (error == 0)
525 		error = nfs_refresh_inode(inode, fattr);
526 	nfs_free_fattr(fattr);
527 out:
528 	trace_nfs_setattr_exit(inode, error);
529 	return error;
530 }
531 EXPORT_SYMBOL_GPL(nfs_setattr);
532 
533 /**
534  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
535  * @inode: inode of the file used
536  * @offset: file offset to start truncating
537  *
538  * This is a copy of the common vmtruncate, but with the locking
539  * corrected to take into account the fact that NFS requires
540  * inode->i_size to be updated under the inode->i_lock.
541  */
542 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
543 {
544 	loff_t oldsize;
545 	int err;
546 
547 	err = inode_newsize_ok(inode, offset);
548 	if (err)
549 		goto out;
550 
551 	spin_lock(&inode->i_lock);
552 	oldsize = inode->i_size;
553 	i_size_write(inode, offset);
554 	spin_unlock(&inode->i_lock);
555 
556 	truncate_pagecache(inode, oldsize, offset);
557 out:
558 	return err;
559 }
560 
561 /**
562  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
563  * @inode: pointer to struct inode
564  * @attr: pointer to struct iattr
565  *
566  * Note: we do this in the *proc.c in order to ensure that
567  *       it works for things like exclusive creates too.
568  */
569 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
570 {
571 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
572 		spin_lock(&inode->i_lock);
573 		if ((attr->ia_valid & ATTR_MODE) != 0) {
574 			int mode = attr->ia_mode & S_IALLUGO;
575 			mode |= inode->i_mode & ~S_IALLUGO;
576 			inode->i_mode = mode;
577 		}
578 		if ((attr->ia_valid & ATTR_UID) != 0)
579 			inode->i_uid = attr->ia_uid;
580 		if ((attr->ia_valid & ATTR_GID) != 0)
581 			inode->i_gid = attr->ia_gid;
582 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
583 		spin_unlock(&inode->i_lock);
584 	}
585 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
586 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
587 		nfs_vmtruncate(inode, attr->ia_size);
588 	}
589 }
590 EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
591 
592 int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
593 {
594 	struct inode *inode = dentry->d_inode;
595 	int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
596 	int err;
597 
598 	trace_nfs_getattr_enter(inode);
599 	/* Flush out writes to the server in order to update c/mtime.  */
600 	if (S_ISREG(inode->i_mode)) {
601 		nfs_inode_dio_wait(inode);
602 		err = filemap_write_and_wait(inode->i_mapping);
603 		if (err)
604 			goto out;
605 	}
606 
607 	/*
608 	 * We may force a getattr if the user cares about atime.
609 	 *
610 	 * Note that we only have to check the vfsmount flags here:
611 	 *  - NFS always sets S_NOATIME by so checking it would give a
612 	 *    bogus result
613 	 *  - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
614 	 *    no point in checking those.
615 	 */
616  	if ((mnt->mnt_flags & MNT_NOATIME) ||
617  	    ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
618 		need_atime = 0;
619 
620 	if (need_atime)
621 		err = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
622 	else
623 		err = nfs_revalidate_inode(NFS_SERVER(inode), inode);
624 	if (!err) {
625 		generic_fillattr(inode, stat);
626 		stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
627 	}
628 out:
629 	trace_nfs_getattr_exit(inode, err);
630 	return err;
631 }
632 EXPORT_SYMBOL_GPL(nfs_getattr);
633 
634 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
635 {
636 	atomic_set(&l_ctx->count, 1);
637 	l_ctx->lockowner.l_owner = current->files;
638 	l_ctx->lockowner.l_pid = current->tgid;
639 	INIT_LIST_HEAD(&l_ctx->list);
640 	nfs_iocounter_init(&l_ctx->io_count);
641 }
642 
643 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
644 {
645 	struct nfs_lock_context *head = &ctx->lock_context;
646 	struct nfs_lock_context *pos = head;
647 
648 	do {
649 		if (pos->lockowner.l_owner != current->files)
650 			continue;
651 		if (pos->lockowner.l_pid != current->tgid)
652 			continue;
653 		atomic_inc(&pos->count);
654 		return pos;
655 	} while ((pos = list_entry(pos->list.next, typeof(*pos), list)) != head);
656 	return NULL;
657 }
658 
659 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
660 {
661 	struct nfs_lock_context *res, *new = NULL;
662 	struct inode *inode = ctx->dentry->d_inode;
663 
664 	spin_lock(&inode->i_lock);
665 	res = __nfs_find_lock_context(ctx);
666 	if (res == NULL) {
667 		spin_unlock(&inode->i_lock);
668 		new = kmalloc(sizeof(*new), GFP_KERNEL);
669 		if (new == NULL)
670 			return ERR_PTR(-ENOMEM);
671 		nfs_init_lock_context(new);
672 		spin_lock(&inode->i_lock);
673 		res = __nfs_find_lock_context(ctx);
674 		if (res == NULL) {
675 			list_add_tail(&new->list, &ctx->lock_context.list);
676 			new->open_context = ctx;
677 			res = new;
678 			new = NULL;
679 		}
680 	}
681 	spin_unlock(&inode->i_lock);
682 	kfree(new);
683 	return res;
684 }
685 
686 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
687 {
688 	struct nfs_open_context *ctx = l_ctx->open_context;
689 	struct inode *inode = ctx->dentry->d_inode;
690 
691 	if (!atomic_dec_and_lock(&l_ctx->count, &inode->i_lock))
692 		return;
693 	list_del(&l_ctx->list);
694 	spin_unlock(&inode->i_lock);
695 	kfree(l_ctx);
696 }
697 
698 /**
699  * nfs_close_context - Common close_context() routine NFSv2/v3
700  * @ctx: pointer to context
701  * @is_sync: is this a synchronous close
702  *
703  * always ensure that the attributes are up to date if we're mounted
704  * with close-to-open semantics
705  */
706 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
707 {
708 	struct inode *inode;
709 	struct nfs_server *server;
710 
711 	if (!(ctx->mode & FMODE_WRITE))
712 		return;
713 	if (!is_sync)
714 		return;
715 	inode = ctx->dentry->d_inode;
716 	if (!list_empty(&NFS_I(inode)->open_files))
717 		return;
718 	server = NFS_SERVER(inode);
719 	if (server->flags & NFS_MOUNT_NOCTO)
720 		return;
721 	nfs_revalidate_inode(server, inode);
722 }
723 EXPORT_SYMBOL_GPL(nfs_close_context);
724 
725 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode)
726 {
727 	struct nfs_open_context *ctx;
728 	struct rpc_cred *cred = rpc_lookup_cred();
729 	if (IS_ERR(cred))
730 		return ERR_CAST(cred);
731 
732 	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
733 	if (!ctx) {
734 		put_rpccred(cred);
735 		return ERR_PTR(-ENOMEM);
736 	}
737 	nfs_sb_active(dentry->d_sb);
738 	ctx->dentry = dget(dentry);
739 	ctx->cred = cred;
740 	ctx->state = NULL;
741 	ctx->mode = f_mode;
742 	ctx->flags = 0;
743 	ctx->error = 0;
744 	nfs_init_lock_context(&ctx->lock_context);
745 	ctx->lock_context.open_context = ctx;
746 	INIT_LIST_HEAD(&ctx->list);
747 	ctx->mdsthreshold = NULL;
748 	return ctx;
749 }
750 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
751 
752 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
753 {
754 	if (ctx != NULL)
755 		atomic_inc(&ctx->lock_context.count);
756 	return ctx;
757 }
758 EXPORT_SYMBOL_GPL(get_nfs_open_context);
759 
760 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
761 {
762 	struct inode *inode = ctx->dentry->d_inode;
763 	struct super_block *sb = ctx->dentry->d_sb;
764 
765 	if (!list_empty(&ctx->list)) {
766 		if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
767 			return;
768 		list_del(&ctx->list);
769 		spin_unlock(&inode->i_lock);
770 	} else if (!atomic_dec_and_test(&ctx->lock_context.count))
771 		return;
772 	if (inode != NULL)
773 		NFS_PROTO(inode)->close_context(ctx, is_sync);
774 	if (ctx->cred != NULL)
775 		put_rpccred(ctx->cred);
776 	dput(ctx->dentry);
777 	nfs_sb_deactive(sb);
778 	kfree(ctx->mdsthreshold);
779 	kfree(ctx);
780 }
781 
782 void put_nfs_open_context(struct nfs_open_context *ctx)
783 {
784 	__put_nfs_open_context(ctx, 0);
785 }
786 EXPORT_SYMBOL_GPL(put_nfs_open_context);
787 
788 /*
789  * Ensure that mmap has a recent RPC credential for use when writing out
790  * shared pages
791  */
792 void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
793 {
794 	struct inode *inode = ctx->dentry->d_inode;
795 	struct nfs_inode *nfsi = NFS_I(inode);
796 
797 	spin_lock(&inode->i_lock);
798 	list_add(&ctx->list, &nfsi->open_files);
799 	spin_unlock(&inode->i_lock);
800 }
801 EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
802 
803 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
804 {
805 	filp->private_data = get_nfs_open_context(ctx);
806 	if (list_empty(&ctx->list))
807 		nfs_inode_attach_open_context(ctx);
808 }
809 EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
810 
811 /*
812  * Given an inode, search for an open context with the desired characteristics
813  */
814 struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode)
815 {
816 	struct nfs_inode *nfsi = NFS_I(inode);
817 	struct nfs_open_context *pos, *ctx = NULL;
818 
819 	spin_lock(&inode->i_lock);
820 	list_for_each_entry(pos, &nfsi->open_files, list) {
821 		if (cred != NULL && pos->cred != cred)
822 			continue;
823 		if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
824 			continue;
825 		ctx = get_nfs_open_context(pos);
826 		break;
827 	}
828 	spin_unlock(&inode->i_lock);
829 	return ctx;
830 }
831 
832 static void nfs_file_clear_open_context(struct file *filp)
833 {
834 	struct nfs_open_context *ctx = nfs_file_open_context(filp);
835 
836 	if (ctx) {
837 		struct inode *inode = ctx->dentry->d_inode;
838 
839 		filp->private_data = NULL;
840 		spin_lock(&inode->i_lock);
841 		list_move_tail(&ctx->list, &NFS_I(inode)->open_files);
842 		spin_unlock(&inode->i_lock);
843 		__put_nfs_open_context(ctx, filp->f_flags & O_DIRECT ? 0 : 1);
844 	}
845 }
846 
847 /*
848  * These allocate and release file read/write context information.
849  */
850 int nfs_open(struct inode *inode, struct file *filp)
851 {
852 	struct nfs_open_context *ctx;
853 
854 	ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
855 	if (IS_ERR(ctx))
856 		return PTR_ERR(ctx);
857 	nfs_file_set_open_context(filp, ctx);
858 	put_nfs_open_context(ctx);
859 	nfs_fscache_set_inode_cookie(inode, filp);
860 	return 0;
861 }
862 
863 int nfs_release(struct inode *inode, struct file *filp)
864 {
865 	nfs_file_clear_open_context(filp);
866 	return 0;
867 }
868 
869 /*
870  * This function is called whenever some part of NFS notices that
871  * the cached attributes have to be refreshed.
872  */
873 int
874 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
875 {
876 	int		 status = -ESTALE;
877 	struct nfs4_label *label = NULL;
878 	struct nfs_fattr *fattr = NULL;
879 	struct nfs_inode *nfsi = NFS_I(inode);
880 
881 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Ld)\n",
882 		inode->i_sb->s_id, (long long)NFS_FILEID(inode));
883 
884 	trace_nfs_revalidate_inode_enter(inode);
885 
886 	if (is_bad_inode(inode))
887 		goto out;
888 	if (NFS_STALE(inode))
889 		goto out;
890 
891 	status = -ENOMEM;
892 	fattr = nfs_alloc_fattr();
893 	if (fattr == NULL)
894 		goto out;
895 
896 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
897 
898 	label = nfs4_label_alloc(NFS_SERVER(inode), GFP_KERNEL);
899 	if (IS_ERR(label)) {
900 		status = PTR_ERR(label);
901 		goto out;
902 	}
903 
904 	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr, label);
905 	if (status != 0) {
906 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) getattr failed, error=%d\n",
907 			 inode->i_sb->s_id,
908 			 (long long)NFS_FILEID(inode), status);
909 		if (status == -ESTALE) {
910 			nfs_zap_caches(inode);
911 			if (!S_ISDIR(inode->i_mode))
912 				set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
913 		}
914 		goto err_out;
915 	}
916 
917 	status = nfs_refresh_inode(inode, fattr);
918 	if (status) {
919 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) refresh failed, error=%d\n",
920 			 inode->i_sb->s_id,
921 			 (long long)NFS_FILEID(inode), status);
922 		goto err_out;
923 	}
924 
925 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
926 		nfs_zap_acl_cache(inode);
927 
928 	dfprintk(PAGECACHE, "NFS: (%s/%Ld) revalidation complete\n",
929 		inode->i_sb->s_id,
930 		(long long)NFS_FILEID(inode));
931 
932 err_out:
933 	nfs4_label_free(label);
934 out:
935 	nfs_free_fattr(fattr);
936 	trace_nfs_revalidate_inode_exit(inode, status);
937 	return status;
938 }
939 
940 int nfs_attribute_timeout(struct inode *inode)
941 {
942 	struct nfs_inode *nfsi = NFS_I(inode);
943 
944 	return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
945 }
946 
947 int nfs_attribute_cache_expired(struct inode *inode)
948 {
949 	if (nfs_have_delegated_attributes(inode))
950 		return 0;
951 	return nfs_attribute_timeout(inode);
952 }
953 
954 /**
955  * nfs_revalidate_inode - Revalidate the inode attributes
956  * @server - pointer to nfs_server struct
957  * @inode - pointer to inode struct
958  *
959  * Updates inode attribute information by retrieving the data from the server.
960  */
961 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
962 {
963 	if (!(NFS_I(inode)->cache_validity &
964 			(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
965 			&& !nfs_attribute_cache_expired(inode))
966 		return NFS_STALE(inode) ? -ESTALE : 0;
967 	return __nfs_revalidate_inode(server, inode);
968 }
969 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
970 
971 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
972 {
973 	struct nfs_inode *nfsi = NFS_I(inode);
974 	int ret;
975 
976 	if (mapping->nrpages != 0) {
977 		if (S_ISREG(inode->i_mode)) {
978 			ret = nfs_sync_mapping(mapping);
979 			if (ret < 0)
980 				return ret;
981 		}
982 		ret = invalidate_inode_pages2(mapping);
983 		if (ret < 0)
984 			return ret;
985 	}
986 	spin_lock(&inode->i_lock);
987 	nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
988 	if (S_ISDIR(inode->i_mode))
989 		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
990 	spin_unlock(&inode->i_lock);
991 	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
992 	nfs_fscache_wait_on_invalidate(inode);
993 
994 	dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
995 			inode->i_sb->s_id, (long long)NFS_FILEID(inode));
996 	return 0;
997 }
998 
999 static bool nfs_mapping_need_revalidate_inode(struct inode *inode)
1000 {
1001 	if (nfs_have_delegated_attributes(inode))
1002 		return false;
1003 	return (NFS_I(inode)->cache_validity & NFS_INO_REVAL_PAGECACHE)
1004 		|| nfs_attribute_timeout(inode)
1005 		|| NFS_STALE(inode);
1006 }
1007 
1008 /**
1009  * nfs_revalidate_mapping - Revalidate the pagecache
1010  * @inode - pointer to host inode
1011  * @mapping - pointer to mapping
1012  */
1013 int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
1014 {
1015 	struct nfs_inode *nfsi = NFS_I(inode);
1016 	int ret = 0;
1017 
1018 	/* swapfiles are not supposed to be shared. */
1019 	if (IS_SWAPFILE(inode))
1020 		goto out;
1021 
1022 	if (nfs_mapping_need_revalidate_inode(inode)) {
1023 		ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1024 		if (ret < 0)
1025 			goto out;
1026 	}
1027 	if (nfsi->cache_validity & NFS_INO_INVALID_DATA) {
1028 		trace_nfs_invalidate_mapping_enter(inode);
1029 		ret = nfs_invalidate_mapping(inode, mapping);
1030 		trace_nfs_invalidate_mapping_exit(inode, ret);
1031 	}
1032 
1033 out:
1034 	return ret;
1035 }
1036 
1037 static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1038 {
1039 	struct nfs_inode *nfsi = NFS_I(inode);
1040 	unsigned long ret = 0;
1041 
1042 	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
1043 			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
1044 			&& inode->i_version == fattr->pre_change_attr) {
1045 		inode->i_version = fattr->change_attr;
1046 		if (S_ISDIR(inode->i_mode))
1047 			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
1048 		ret |= NFS_INO_INVALID_ATTR;
1049 	}
1050 	/* If we have atomic WCC data, we may update some attributes */
1051 	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
1052 			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
1053 			&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
1054 		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1055 		ret |= NFS_INO_INVALID_ATTR;
1056 	}
1057 
1058 	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
1059 			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
1060 			&& timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
1061 		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1062 		if (S_ISDIR(inode->i_mode))
1063 			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
1064 		ret |= NFS_INO_INVALID_ATTR;
1065 	}
1066 	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
1067 			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
1068 			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
1069 			&& nfsi->npages == 0) {
1070 		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
1071 		ret |= NFS_INO_INVALID_ATTR;
1072 	}
1073 
1074 	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1075 		nfs_fscache_invalidate(inode);
1076 
1077 	return ret;
1078 }
1079 
1080 /**
1081  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1082  * @inode - pointer to inode
1083  * @fattr - updated attributes
1084  *
1085  * Verifies the attribute cache. If we have just changed the attributes,
1086  * so that fattr carries weak cache consistency data, then it may
1087  * also update the ctime/mtime/change_attribute.
1088  */
1089 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1090 {
1091 	struct nfs_inode *nfsi = NFS_I(inode);
1092 	loff_t cur_size, new_isize;
1093 	unsigned long invalid = 0;
1094 
1095 
1096 	if (nfs_have_delegated_attributes(inode))
1097 		return 0;
1098 	/* Has the inode gone and changed behind our back? */
1099 	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
1100 		return -EIO;
1101 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
1102 		return -EIO;
1103 
1104 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1105 			inode->i_version != fattr->change_attr)
1106 		invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1107 
1108 	/* Verify a few of the more important attributes */
1109 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec_equal(&inode->i_mtime, &fattr->mtime))
1110 		invalid |= NFS_INO_INVALID_ATTR;
1111 
1112 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1113 		cur_size = i_size_read(inode);
1114 		new_isize = nfs_size_to_loff_t(fattr->size);
1115 		if (cur_size != new_isize && nfsi->npages == 0)
1116 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1117 	}
1118 
1119 	/* Have any file permissions changed? */
1120 	if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
1121 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1122 	if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && !uid_eq(inode->i_uid, fattr->uid))
1123 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1124 	if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && !gid_eq(inode->i_gid, fattr->gid))
1125 		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1126 
1127 	/* Has the link count changed? */
1128 	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
1129 		invalid |= NFS_INO_INVALID_ATTR;
1130 
1131 	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec_equal(&inode->i_atime, &fattr->atime))
1132 		invalid |= NFS_INO_INVALID_ATIME;
1133 
1134 	if (invalid != 0)
1135 		nfsi->cache_validity |= invalid;
1136 
1137 	nfsi->read_cache_jiffies = fattr->time_start;
1138 	return 0;
1139 }
1140 
1141 static int nfs_ctime_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1142 {
1143 	if (!(fattr->valid & NFS_ATTR_FATTR_CTIME))
1144 		return 0;
1145 	return timespec_compare(&fattr->ctime, &inode->i_ctime) > 0;
1146 }
1147 
1148 static int nfs_size_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1149 {
1150 	if (!(fattr->valid & NFS_ATTR_FATTR_SIZE))
1151 		return 0;
1152 	return nfs_size_to_loff_t(fattr->size) > i_size_read(inode);
1153 }
1154 
1155 static atomic_long_t nfs_attr_generation_counter;
1156 
1157 static unsigned long nfs_read_attr_generation_counter(void)
1158 {
1159 	return atomic_long_read(&nfs_attr_generation_counter);
1160 }
1161 
1162 unsigned long nfs_inc_attr_generation_counter(void)
1163 {
1164 	return atomic_long_inc_return(&nfs_attr_generation_counter);
1165 }
1166 
1167 void nfs_fattr_init(struct nfs_fattr *fattr)
1168 {
1169 	fattr->valid = 0;
1170 	fattr->time_start = jiffies;
1171 	fattr->gencount = nfs_inc_attr_generation_counter();
1172 	fattr->owner_name = NULL;
1173 	fattr->group_name = NULL;
1174 }
1175 EXPORT_SYMBOL_GPL(nfs_fattr_init);
1176 
1177 struct nfs_fattr *nfs_alloc_fattr(void)
1178 {
1179 	struct nfs_fattr *fattr;
1180 
1181 	fattr = kmalloc(sizeof(*fattr), GFP_NOFS);
1182 	if (fattr != NULL)
1183 		nfs_fattr_init(fattr);
1184 	return fattr;
1185 }
1186 EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
1187 
1188 struct nfs_fh *nfs_alloc_fhandle(void)
1189 {
1190 	struct nfs_fh *fh;
1191 
1192 	fh = kmalloc(sizeof(struct nfs_fh), GFP_NOFS);
1193 	if (fh != NULL)
1194 		fh->size = 0;
1195 	return fh;
1196 }
1197 EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
1198 
1199 #ifdef NFS_DEBUG
1200 /*
1201  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1202  *                             in the same way that wireshark does
1203  *
1204  * @fh: file handle
1205  *
1206  * For debugging only.
1207  */
1208 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1209 {
1210 	/* wireshark uses 32-bit AUTODIN crc and does a bitwise
1211 	 * not on the result */
1212 	return nfs_fhandle_hash(fh);
1213 }
1214 
1215 /*
1216  * _nfs_display_fhandle - display an NFS file handle on the console
1217  *
1218  * @fh: file handle to display
1219  * @caption: display caption
1220  *
1221  * For debugging only.
1222  */
1223 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1224 {
1225 	unsigned short i;
1226 
1227 	if (fh == NULL || fh->size == 0) {
1228 		printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1229 		return;
1230 	}
1231 
1232 	printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1233 	       caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1234 	for (i = 0; i < fh->size; i += 16) {
1235 		__be32 *pos = (__be32 *)&fh->data[i];
1236 
1237 		switch ((fh->size - i - 1) >> 2) {
1238 		case 0:
1239 			printk(KERN_DEFAULT " %08x\n",
1240 				be32_to_cpup(pos));
1241 			break;
1242 		case 1:
1243 			printk(KERN_DEFAULT " %08x %08x\n",
1244 				be32_to_cpup(pos), be32_to_cpup(pos + 1));
1245 			break;
1246 		case 2:
1247 			printk(KERN_DEFAULT " %08x %08x %08x\n",
1248 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1249 				be32_to_cpup(pos + 2));
1250 			break;
1251 		default:
1252 			printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1253 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1254 				be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1255 		}
1256 	}
1257 }
1258 #endif
1259 
1260 /**
1261  * nfs_inode_attrs_need_update - check if the inode attributes need updating
1262  * @inode - pointer to inode
1263  * @fattr - attributes
1264  *
1265  * Attempt to divine whether or not an RPC call reply carrying stale
1266  * attributes got scheduled after another call carrying updated ones.
1267  *
1268  * To do so, the function first assumes that a more recent ctime means
1269  * that the attributes in fattr are newer, however it also attempt to
1270  * catch the case where ctime either didn't change, or went backwards
1271  * (if someone reset the clock on the server) by looking at whether
1272  * or not this RPC call was started after the inode was last updated.
1273  * Note also the check for wraparound of 'attr_gencount'
1274  *
1275  * The function returns 'true' if it thinks the attributes in 'fattr' are
1276  * more recent than the ones cached in the inode.
1277  *
1278  */
1279 static int nfs_inode_attrs_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1280 {
1281 	const struct nfs_inode *nfsi = NFS_I(inode);
1282 
1283 	return ((long)fattr->gencount - (long)nfsi->attr_gencount) > 0 ||
1284 		nfs_ctime_need_update(inode, fattr) ||
1285 		nfs_size_need_update(inode, fattr) ||
1286 		((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
1287 }
1288 
1289 static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1290 {
1291 	int ret;
1292 
1293 	trace_nfs_refresh_inode_enter(inode);
1294 
1295 	if (nfs_inode_attrs_need_update(inode, fattr))
1296 		ret = nfs_update_inode(inode, fattr);
1297 	else
1298 		ret = nfs_check_inode_attributes(inode, fattr);
1299 
1300 	trace_nfs_refresh_inode_exit(inode, ret);
1301 	return ret;
1302 }
1303 
1304 /**
1305  * nfs_refresh_inode - try to update the inode attribute cache
1306  * @inode - pointer to inode
1307  * @fattr - updated attributes
1308  *
1309  * Check that an RPC call that returned attributes has not overlapped with
1310  * other recent updates of the inode metadata, then decide whether it is
1311  * safe to do a full update of the inode attributes, or whether just to
1312  * call nfs_check_inode_attributes.
1313  */
1314 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
1315 {
1316 	int status;
1317 
1318 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1319 		return 0;
1320 	spin_lock(&inode->i_lock);
1321 	status = nfs_refresh_inode_locked(inode, fattr);
1322 	spin_unlock(&inode->i_lock);
1323 
1324 	return status;
1325 }
1326 EXPORT_SYMBOL_GPL(nfs_refresh_inode);
1327 
1328 static int nfs_post_op_update_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1329 {
1330 	struct nfs_inode *nfsi = NFS_I(inode);
1331 
1332 	nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1333 	if (S_ISDIR(inode->i_mode)) {
1334 		nfsi->cache_validity |= NFS_INO_INVALID_DATA;
1335 		nfs_fscache_invalidate(inode);
1336 	}
1337 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1338 		return 0;
1339 	return nfs_refresh_inode_locked(inode, fattr);
1340 }
1341 
1342 /**
1343  * nfs_post_op_update_inode - try to update the inode attribute cache
1344  * @inode - pointer to inode
1345  * @fattr - updated attributes
1346  *
1347  * After an operation that has changed the inode metadata, mark the
1348  * attribute cache as being invalid, then try to update it.
1349  *
1350  * NB: if the server didn't return any post op attributes, this
1351  * function will force the retrieval of attributes before the next
1352  * NFS request.  Thus it should be used only for operations that
1353  * are expected to change one or more attributes, to avoid
1354  * unnecessary NFS requests and trips through nfs_update_inode().
1355  */
1356 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1357 {
1358 	int status;
1359 
1360 	spin_lock(&inode->i_lock);
1361 	status = nfs_post_op_update_inode_locked(inode, fattr);
1362 	spin_unlock(&inode->i_lock);
1363 
1364 	return status;
1365 }
1366 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
1367 
1368 /**
1369  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
1370  * @inode - pointer to inode
1371  * @fattr - updated attributes
1372  *
1373  * After an operation that has changed the inode metadata, mark the
1374  * attribute cache as being invalid, then try to update it. Fake up
1375  * weak cache consistency data, if none exist.
1376  *
1377  * This function is mainly designed to be used by the ->write_done() functions.
1378  */
1379 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
1380 {
1381 	int status;
1382 
1383 	spin_lock(&inode->i_lock);
1384 	/* Don't do a WCC update if these attributes are already stale */
1385 	if ((fattr->valid & NFS_ATTR_FATTR) == 0 ||
1386 			!nfs_inode_attrs_need_update(inode, fattr)) {
1387 		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
1388 				| NFS_ATTR_FATTR_PRESIZE
1389 				| NFS_ATTR_FATTR_PREMTIME
1390 				| NFS_ATTR_FATTR_PRECTIME);
1391 		goto out_noforce;
1392 	}
1393 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1394 			(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
1395 		fattr->pre_change_attr = inode->i_version;
1396 		fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
1397 	}
1398 	if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
1399 			(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
1400 		memcpy(&fattr->pre_ctime, &inode->i_ctime, sizeof(fattr->pre_ctime));
1401 		fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
1402 	}
1403 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
1404 			(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
1405 		memcpy(&fattr->pre_mtime, &inode->i_mtime, sizeof(fattr->pre_mtime));
1406 		fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
1407 	}
1408 	if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
1409 			(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
1410 		fattr->pre_size = i_size_read(inode);
1411 		fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
1412 	}
1413 out_noforce:
1414 	status = nfs_post_op_update_inode_locked(inode, fattr);
1415 	spin_unlock(&inode->i_lock);
1416 	return status;
1417 }
1418 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
1419 
1420 /*
1421  * Many nfs protocol calls return the new file attributes after
1422  * an operation.  Here we update the inode to reflect the state
1423  * of the server's inode.
1424  *
1425  * This is a bit tricky because we have to make sure all dirty pages
1426  * have been sent off to the server before calling invalidate_inode_pages.
1427  * To make sure no other process adds more write requests while we try
1428  * our best to flush them, we make them sleep during the attribute refresh.
1429  *
1430  * A very similar scenario holds for the dir cache.
1431  */
1432 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1433 {
1434 	struct nfs_server *server;
1435 	struct nfs_inode *nfsi = NFS_I(inode);
1436 	loff_t cur_isize, new_isize;
1437 	unsigned long invalid = 0;
1438 	unsigned long now = jiffies;
1439 	unsigned long save_cache_validity;
1440 
1441 	dfprintk(VFS, "NFS: %s(%s/%ld fh_crc=0x%08x ct=%d info=0x%x)\n",
1442 			__func__, inode->i_sb->s_id, inode->i_ino,
1443 			nfs_display_fhandle_hash(NFS_FH(inode)),
1444 			atomic_read(&inode->i_count), fattr->valid);
1445 
1446 	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid) {
1447 		printk(KERN_ERR "NFS: server %s error: fileid changed\n"
1448 			"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
1449 			NFS_SERVER(inode)->nfs_client->cl_hostname,
1450 			inode->i_sb->s_id, (long long)nfsi->fileid,
1451 			(long long)fattr->fileid);
1452 		goto out_err;
1453 	}
1454 
1455 	/*
1456 	 * Make sure the inode's type hasn't changed.
1457 	 */
1458 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
1459 		/*
1460 		* Big trouble! The inode has become a different object.
1461 		*/
1462 		printk(KERN_DEBUG "NFS: %s: inode %ld mode changed, %07o to %07o\n",
1463 				__func__, inode->i_ino, inode->i_mode, fattr->mode);
1464 		goto out_err;
1465 	}
1466 
1467 	server = NFS_SERVER(inode);
1468 	/* Update the fsid? */
1469 	if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
1470 			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
1471 			!IS_AUTOMOUNT(inode))
1472 		server->fsid = fattr->fsid;
1473 
1474 	/*
1475 	 * Update the read time so we don't revalidate too often.
1476 	 */
1477 	nfsi->read_cache_jiffies = fattr->time_start;
1478 
1479 	save_cache_validity = nfsi->cache_validity;
1480 	nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
1481 			| NFS_INO_INVALID_ATIME
1482 			| NFS_INO_REVAL_FORCED
1483 			| NFS_INO_REVAL_PAGECACHE);
1484 
1485 	/* Do atomic weak cache consistency updates */
1486 	invalid |= nfs_wcc_update_inode(inode, fattr);
1487 
1488 	/* More cache consistency checks */
1489 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
1490 		if (inode->i_version != fattr->change_attr) {
1491 			dprintk("NFS: change_attr change on server for file %s/%ld\n",
1492 					inode->i_sb->s_id, inode->i_ino);
1493 			invalid |= NFS_INO_INVALID_ATTR
1494 				| NFS_INO_INVALID_DATA
1495 				| NFS_INO_INVALID_ACCESS
1496 				| NFS_INO_INVALID_ACL
1497 				| NFS_INO_REVAL_PAGECACHE;
1498 			if (S_ISDIR(inode->i_mode))
1499 				nfs_force_lookup_revalidate(inode);
1500 			inode->i_version = fattr->change_attr;
1501 		}
1502 	} else if (server->caps & NFS_CAP_CHANGE_ATTR)
1503 		invalid |= save_cache_validity;
1504 
1505 	if (fattr->valid & NFS_ATTR_FATTR_MTIME) {
1506 		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1507 	} else if (server->caps & NFS_CAP_MTIME)
1508 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1509 				| NFS_INO_REVAL_FORCED);
1510 
1511 	if (fattr->valid & NFS_ATTR_FATTR_CTIME) {
1512 		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1513 	} else if (server->caps & NFS_CAP_CTIME)
1514 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1515 				| NFS_INO_REVAL_FORCED);
1516 
1517 	/* Check if our cached file size is stale */
1518 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1519 		new_isize = nfs_size_to_loff_t(fattr->size);
1520 		cur_isize = i_size_read(inode);
1521 		if (new_isize != cur_isize) {
1522 			/* Do we perhaps have any outstanding writes, or has
1523 			 * the file grown beyond our last write? */
1524 			if ((nfsi->npages == 0 && !test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) ||
1525 			     new_isize > cur_isize) {
1526 				i_size_write(inode, new_isize);
1527 				invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
1528 			}
1529 			dprintk("NFS: isize change on server for file %s/%ld "
1530 					"(%Ld to %Ld)\n",
1531 					inode->i_sb->s_id,
1532 					inode->i_ino,
1533 					(long long)cur_isize,
1534 					(long long)new_isize);
1535 		}
1536 	} else
1537 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1538 				| NFS_INO_REVAL_PAGECACHE
1539 				| NFS_INO_REVAL_FORCED);
1540 
1541 
1542 	if (fattr->valid & NFS_ATTR_FATTR_ATIME)
1543 		memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
1544 	else if (server->caps & NFS_CAP_ATIME)
1545 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATIME
1546 				| NFS_INO_REVAL_FORCED);
1547 
1548 	if (fattr->valid & NFS_ATTR_FATTR_MODE) {
1549 		if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
1550 			umode_t newmode = inode->i_mode & S_IFMT;
1551 			newmode |= fattr->mode & S_IALLUGO;
1552 			inode->i_mode = newmode;
1553 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1554 		}
1555 	} else if (server->caps & NFS_CAP_MODE)
1556 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1557 				| NFS_INO_INVALID_ACCESS
1558 				| NFS_INO_INVALID_ACL
1559 				| NFS_INO_REVAL_FORCED);
1560 
1561 	if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
1562 		if (!uid_eq(inode->i_uid, fattr->uid)) {
1563 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1564 			inode->i_uid = fattr->uid;
1565 		}
1566 	} else if (server->caps & NFS_CAP_OWNER)
1567 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1568 				| NFS_INO_INVALID_ACCESS
1569 				| NFS_INO_INVALID_ACL
1570 				| NFS_INO_REVAL_FORCED);
1571 
1572 	if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
1573 		if (!gid_eq(inode->i_gid, fattr->gid)) {
1574 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1575 			inode->i_gid = fattr->gid;
1576 		}
1577 	} else if (server->caps & NFS_CAP_OWNER_GROUP)
1578 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1579 				| NFS_INO_INVALID_ACCESS
1580 				| NFS_INO_INVALID_ACL
1581 				| NFS_INO_REVAL_FORCED);
1582 
1583 	if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
1584 		if (inode->i_nlink != fattr->nlink) {
1585 			invalid |= NFS_INO_INVALID_ATTR;
1586 			if (S_ISDIR(inode->i_mode))
1587 				invalid |= NFS_INO_INVALID_DATA;
1588 			set_nlink(inode, fattr->nlink);
1589 		}
1590 	} else if (server->caps & NFS_CAP_NLINK)
1591 		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
1592 				| NFS_INO_REVAL_FORCED);
1593 
1594 	if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
1595 		/*
1596 		 * report the blocks in 512byte units
1597 		 */
1598 		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
1599  	}
1600 	if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
1601 		inode->i_blocks = fattr->du.nfs2.blocks;
1602 
1603 	/* Update attrtimeo value if we're out of the unstable period */
1604 	if (invalid & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL)) {
1605 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
1606 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
1607 		nfsi->attrtimeo_timestamp = now;
1608 		nfsi->attr_gencount = nfs_inc_attr_generation_counter();
1609 	} else {
1610 		if (!time_in_range_open(now, nfsi->attrtimeo_timestamp, nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
1611 			if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
1612 				nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
1613 			nfsi->attrtimeo_timestamp = now;
1614 		}
1615 	}
1616 	invalid &= ~NFS_INO_INVALID_ATTR;
1617 	invalid &= ~NFS_INO_INVALID_LABEL;
1618 	/* Don't invalidate the data if we were to blame */
1619 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
1620 				|| S_ISLNK(inode->i_mode)))
1621 		invalid &= ~NFS_INO_INVALID_DATA;
1622 	if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ) ||
1623 			(save_cache_validity & NFS_INO_REVAL_FORCED))
1624 		nfsi->cache_validity |= invalid;
1625 
1626 	if (invalid & NFS_INO_INVALID_DATA)
1627 		nfs_fscache_invalidate(inode);
1628 
1629 	return 0;
1630  out_err:
1631 	/*
1632 	 * No need to worry about unhashing the dentry, as the
1633 	 * lookup validation will know that the inode is bad.
1634 	 * (But we fall through to invalidate the caches.)
1635 	 */
1636 	nfs_invalidate_inode(inode);
1637 	return -ESTALE;
1638 }
1639 
1640 struct inode *nfs_alloc_inode(struct super_block *sb)
1641 {
1642 	struct nfs_inode *nfsi;
1643 	nfsi = (struct nfs_inode *)kmem_cache_alloc(nfs_inode_cachep, GFP_KERNEL);
1644 	if (!nfsi)
1645 		return NULL;
1646 	nfsi->flags = 0UL;
1647 	nfsi->cache_validity = 0UL;
1648 #ifdef CONFIG_NFS_V3_ACL
1649 	nfsi->acl_access = ERR_PTR(-EAGAIN);
1650 	nfsi->acl_default = ERR_PTR(-EAGAIN);
1651 #endif
1652 #if IS_ENABLED(CONFIG_NFS_V4)
1653 	nfsi->nfs4_acl = NULL;
1654 #endif /* CONFIG_NFS_V4 */
1655 	return &nfsi->vfs_inode;
1656 }
1657 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
1658 
1659 static void nfs_i_callback(struct rcu_head *head)
1660 {
1661 	struct inode *inode = container_of(head, struct inode, i_rcu);
1662 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
1663 }
1664 
1665 void nfs_destroy_inode(struct inode *inode)
1666 {
1667 	call_rcu(&inode->i_rcu, nfs_i_callback);
1668 }
1669 EXPORT_SYMBOL_GPL(nfs_destroy_inode);
1670 
1671 static inline void nfs4_init_once(struct nfs_inode *nfsi)
1672 {
1673 #if IS_ENABLED(CONFIG_NFS_V4)
1674 	INIT_LIST_HEAD(&nfsi->open_states);
1675 	nfsi->delegation = NULL;
1676 	nfsi->delegation_state = 0;
1677 	init_rwsem(&nfsi->rwsem);
1678 	nfsi->layout = NULL;
1679 #endif
1680 }
1681 
1682 static void init_once(void *foo)
1683 {
1684 	struct nfs_inode *nfsi = (struct nfs_inode *) foo;
1685 
1686 	inode_init_once(&nfsi->vfs_inode);
1687 	INIT_LIST_HEAD(&nfsi->open_files);
1688 	INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
1689 	INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
1690 	INIT_LIST_HEAD(&nfsi->commit_info.list);
1691 	nfsi->npages = 0;
1692 	nfsi->commit_info.ncommit = 0;
1693 	atomic_set(&nfsi->commit_info.rpcs_out, 0);
1694 	atomic_set(&nfsi->silly_count, 1);
1695 	INIT_HLIST_HEAD(&nfsi->silly_list);
1696 	init_waitqueue_head(&nfsi->waitqueue);
1697 	nfs4_init_once(nfsi);
1698 }
1699 
1700 static int __init nfs_init_inodecache(void)
1701 {
1702 	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
1703 					     sizeof(struct nfs_inode),
1704 					     0, (SLAB_RECLAIM_ACCOUNT|
1705 						SLAB_MEM_SPREAD),
1706 					     init_once);
1707 	if (nfs_inode_cachep == NULL)
1708 		return -ENOMEM;
1709 
1710 	return 0;
1711 }
1712 
1713 static void nfs_destroy_inodecache(void)
1714 {
1715 	/*
1716 	 * Make sure all delayed rcu free inodes are flushed before we
1717 	 * destroy cache.
1718 	 */
1719 	rcu_barrier();
1720 	kmem_cache_destroy(nfs_inode_cachep);
1721 }
1722 
1723 struct workqueue_struct *nfsiod_workqueue;
1724 EXPORT_SYMBOL_GPL(nfsiod_workqueue);
1725 
1726 /*
1727  * start up the nfsiod workqueue
1728  */
1729 static int nfsiod_start(void)
1730 {
1731 	struct workqueue_struct *wq;
1732 	dprintk("RPC:       creating workqueue nfsiod\n");
1733 	wq = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM, 0);
1734 	if (wq == NULL)
1735 		return -ENOMEM;
1736 	nfsiod_workqueue = wq;
1737 	return 0;
1738 }
1739 
1740 /*
1741  * Destroy the nfsiod workqueue
1742  */
1743 static void nfsiod_stop(void)
1744 {
1745 	struct workqueue_struct *wq;
1746 
1747 	wq = nfsiod_workqueue;
1748 	if (wq == NULL)
1749 		return;
1750 	nfsiod_workqueue = NULL;
1751 	destroy_workqueue(wq);
1752 }
1753 
1754 int nfs_net_id;
1755 EXPORT_SYMBOL_GPL(nfs_net_id);
1756 
1757 static int nfs_net_init(struct net *net)
1758 {
1759 	nfs_clients_init(net);
1760 	return 0;
1761 }
1762 
1763 static void nfs_net_exit(struct net *net)
1764 {
1765 	nfs_cleanup_cb_ident_idr(net);
1766 }
1767 
1768 static struct pernet_operations nfs_net_ops = {
1769 	.init = nfs_net_init,
1770 	.exit = nfs_net_exit,
1771 	.id   = &nfs_net_id,
1772 	.size = sizeof(struct nfs_net),
1773 };
1774 
1775 /*
1776  * Initialize NFS
1777  */
1778 static int __init init_nfs_fs(void)
1779 {
1780 	int err;
1781 
1782 	err = register_pernet_subsys(&nfs_net_ops);
1783 	if (err < 0)
1784 		goto out9;
1785 
1786 	err = nfs_fscache_register();
1787 	if (err < 0)
1788 		goto out8;
1789 
1790 	err = nfsiod_start();
1791 	if (err)
1792 		goto out7;
1793 
1794 	err = nfs_fs_proc_init();
1795 	if (err)
1796 		goto out6;
1797 
1798 	err = nfs_init_nfspagecache();
1799 	if (err)
1800 		goto out5;
1801 
1802 	err = nfs_init_inodecache();
1803 	if (err)
1804 		goto out4;
1805 
1806 	err = nfs_init_readpagecache();
1807 	if (err)
1808 		goto out3;
1809 
1810 	err = nfs_init_writepagecache();
1811 	if (err)
1812 		goto out2;
1813 
1814 	err = nfs_init_directcache();
1815 	if (err)
1816 		goto out1;
1817 
1818 #ifdef CONFIG_PROC_FS
1819 	rpc_proc_register(&init_net, &nfs_rpcstat);
1820 #endif
1821 	if ((err = register_nfs_fs()) != 0)
1822 		goto out0;
1823 
1824 	return 0;
1825 out0:
1826 #ifdef CONFIG_PROC_FS
1827 	rpc_proc_unregister(&init_net, "nfs");
1828 #endif
1829 	nfs_destroy_directcache();
1830 out1:
1831 	nfs_destroy_writepagecache();
1832 out2:
1833 	nfs_destroy_readpagecache();
1834 out3:
1835 	nfs_destroy_inodecache();
1836 out4:
1837 	nfs_destroy_nfspagecache();
1838 out5:
1839 	nfs_fs_proc_exit();
1840 out6:
1841 	nfsiod_stop();
1842 out7:
1843 	nfs_fscache_unregister();
1844 out8:
1845 	unregister_pernet_subsys(&nfs_net_ops);
1846 out9:
1847 	return err;
1848 }
1849 
1850 static void __exit exit_nfs_fs(void)
1851 {
1852 	nfs_destroy_directcache();
1853 	nfs_destroy_writepagecache();
1854 	nfs_destroy_readpagecache();
1855 	nfs_destroy_inodecache();
1856 	nfs_destroy_nfspagecache();
1857 	nfs_fscache_unregister();
1858 	unregister_pernet_subsys(&nfs_net_ops);
1859 #ifdef CONFIG_PROC_FS
1860 	rpc_proc_unregister(&init_net, "nfs");
1861 #endif
1862 	unregister_nfs_fs();
1863 	nfs_fs_proc_exit();
1864 	nfsiod_stop();
1865 }
1866 
1867 /* Not quite true; I just maintain it */
1868 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
1869 MODULE_LICENSE("GPL");
1870 module_param(enable_ino64, bool, 0644);
1871 
1872 module_init(init_nfs_fs)
1873 module_exit(exit_nfs_fs)
1874