xref: /linux/fs/nfs/inode.c (revision 070a542f08acb7e8cf197287f5c44658c715d2d1)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/fs/nfs/inode.c
4  *
5  *  Copyright (C) 1992  Rick Sladkey
6  *
7  *  nfs inode and superblock handling functions
8  *
9  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
10  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
11  *
12  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
13  *  J.S.Peatfield@damtp.cam.ac.uk
14  *
15  */
16 
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/sched/signal.h>
20 #include <linux/time.h>
21 #include <linux/kernel.h>
22 #include <linux/mm.h>
23 #include <linux/string.h>
24 #include <linux/stat.h>
25 #include <linux/errno.h>
26 #include <linux/unistd.h>
27 #include <linux/sunrpc/clnt.h>
28 #include <linux/sunrpc/stats.h>
29 #include <linux/sunrpc/metrics.h>
30 #include <linux/nfs_fs.h>
31 #include <linux/nfs_mount.h>
32 #include <linux/nfs4_mount.h>
33 #include <linux/lockd/bind.h>
34 #include <linux/seq_file.h>
35 #include <linux/mount.h>
36 #include <linux/vfs.h>
37 #include <linux/inet.h>
38 #include <linux/nfs_xdr.h>
39 #include <linux/slab.h>
40 #include <linux/compat.h>
41 #include <linux/freezer.h>
42 #include <linux/uaccess.h>
43 #include <linux/iversion.h>
44 
45 #include "nfs4_fs.h"
46 #include "callback.h"
47 #include "delegation.h"
48 #include "iostat.h"
49 #include "internal.h"
50 #include "fscache.h"
51 #include "pnfs.h"
52 #include "nfs.h"
53 #include "netns.h"
54 #include "sysfs.h"
55 
56 #include "nfstrace.h"
57 
58 #define NFSDBG_FACILITY		NFSDBG_VFS
59 
60 #define NFS_64_BIT_INODE_NUMBERS_ENABLED	1
61 
62 /* Default is to see 64-bit inode numbers */
63 static bool enable_ino64 = NFS_64_BIT_INODE_NUMBERS_ENABLED;
64 
65 static int nfs_update_inode(struct inode *, struct nfs_fattr *);
66 
67 static struct kmem_cache * nfs_inode_cachep;
68 
69 static inline unsigned long
nfs_fattr_to_ino_t(struct nfs_fattr * fattr)70 nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
71 {
72 	return nfs_fileid_to_ino_t(fattr->fileid);
73 }
74 
nfs_wait_bit_killable(struct wait_bit_key * key,int mode)75 int nfs_wait_bit_killable(struct wait_bit_key *key, int mode)
76 {
77 	if (unlikely(nfs_current_task_exiting()))
78 		return -EINTR;
79 	schedule();
80 	if (signal_pending_state(mode, current))
81 		return -ERESTARTSYS;
82 	return 0;
83 }
84 EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
85 
86 /**
87  * nfs_compat_user_ino64 - returns the user-visible inode number
88  * @fileid: 64-bit fileid
89  *
90  * This function returns a 32-bit inode number if the boot parameter
91  * nfs.enable_ino64 is zero.
92  */
nfs_compat_user_ino64(u64 fileid)93 u64 nfs_compat_user_ino64(u64 fileid)
94 {
95 #ifdef CONFIG_COMPAT
96 	compat_ulong_t ino;
97 #else
98 	unsigned long ino;
99 #endif
100 
101 	if (enable_ino64)
102 		return fileid;
103 	ino = fileid;
104 	if (sizeof(ino) < sizeof(fileid))
105 		ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
106 	return ino;
107 }
108 
nfs_drop_inode(struct inode * inode)109 int nfs_drop_inode(struct inode *inode)
110 {
111 	return NFS_STALE(inode) || inode_generic_drop(inode);
112 }
113 EXPORT_SYMBOL_GPL(nfs_drop_inode);
114 
nfs_clear_inode(struct inode * inode)115 void nfs_clear_inode(struct inode *inode)
116 {
117 	/*
118 	 * The following should never happen...
119 	 */
120 	WARN_ON_ONCE(nfs_have_writebacks(inode));
121 	WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files));
122 	nfs_zap_acl_cache(inode);
123 	nfs_access_zap_cache(inode);
124 	nfs_fscache_clear_inode(inode);
125 }
126 EXPORT_SYMBOL_GPL(nfs_clear_inode);
127 
nfs_evict_inode(struct inode * inode)128 void nfs_evict_inode(struct inode *inode)
129 {
130 	truncate_inode_pages_final(&inode->i_data);
131 	clear_inode(inode);
132 	nfs_clear_inode(inode);
133 }
134 
nfs_sync_inode(struct inode * inode)135 int nfs_sync_inode(struct inode *inode)
136 {
137 	inode_dio_wait(inode);
138 	return nfs_wb_all(inode);
139 }
140 EXPORT_SYMBOL_GPL(nfs_sync_inode);
141 
142 /**
143  * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
144  * @mapping: pointer to struct address_space
145  */
nfs_sync_mapping(struct address_space * mapping)146 int nfs_sync_mapping(struct address_space *mapping)
147 {
148 	int ret = 0;
149 
150 	if (mapping->nrpages != 0) {
151 		unmap_mapping_range(mapping, 0, 0, 0);
152 		ret = nfs_wb_all(mapping->host);
153 	}
154 	return ret;
155 }
156 
nfs_attribute_timeout(struct inode * inode)157 static int nfs_attribute_timeout(struct inode *inode)
158 {
159 	struct nfs_inode *nfsi = NFS_I(inode);
160 
161 	return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
162 }
163 
nfs_check_cache_flags_invalid(struct inode * inode,unsigned long flags)164 static bool nfs_check_cache_flags_invalid(struct inode *inode,
165 					  unsigned long flags)
166 {
167 	unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
168 
169 	return (cache_validity & flags) != 0;
170 }
171 
nfs_check_cache_invalid(struct inode * inode,unsigned long flags)172 bool nfs_check_cache_invalid(struct inode *inode, unsigned long flags)
173 {
174 	if (nfs_check_cache_flags_invalid(inode, flags))
175 		return true;
176 	return nfs_attribute_cache_expired(inode);
177 }
178 EXPORT_SYMBOL_GPL(nfs_check_cache_invalid);
179 
180 #ifdef CONFIG_NFS_V4_2
nfs_has_xattr_cache(const struct nfs_inode * nfsi)181 static bool nfs_has_xattr_cache(const struct nfs_inode *nfsi)
182 {
183 	return nfsi->xattr_cache != NULL;
184 }
185 #else
nfs_has_xattr_cache(const struct nfs_inode * nfsi)186 static bool nfs_has_xattr_cache(const struct nfs_inode *nfsi)
187 {
188 	return false;
189 }
190 #endif
191 
nfs_set_cache_invalid(struct inode * inode,unsigned long flags)192 void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
193 {
194 	struct nfs_inode *nfsi = NFS_I(inode);
195 
196 	if (nfs_have_delegated_attributes(inode)) {
197 		if (!(flags & NFS_INO_REVAL_FORCED))
198 			flags &= ~(NFS_INO_INVALID_MODE |
199 				   NFS_INO_INVALID_OTHER |
200 				   NFS_INO_INVALID_BTIME |
201 				   NFS_INO_INVALID_XATTR);
202 		flags &= ~(NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_SIZE);
203 	}
204 
205 	if (!nfs_has_xattr_cache(nfsi))
206 		flags &= ~NFS_INO_INVALID_XATTR;
207 	if (flags & NFS_INO_INVALID_DATA)
208 		nfs_fscache_invalidate(inode, 0);
209 	flags &= ~NFS_INO_REVAL_FORCED;
210 
211 	flags |= nfsi->cache_validity;
212 	if (inode->i_mapping->nrpages == 0)
213 		flags &= ~NFS_INO_INVALID_DATA;
214 
215 	/* pairs with nfs_clear_invalid_mapping()'s smp_load_acquire() */
216 	smp_store_release(&nfsi->cache_validity, flags);
217 
218 	if (inode->i_mapping->nrpages == 0 ||
219 	    nfsi->cache_validity & NFS_INO_INVALID_DATA) {
220 		nfs_ooo_clear(nfsi);
221 	}
222 	trace_nfs_set_cache_invalid(inode, 0);
223 }
224 EXPORT_SYMBOL_GPL(nfs_set_cache_invalid);
225 
226 /*
227  * Invalidate the local caches
228  */
nfs_zap_caches_locked(struct inode * inode)229 static void nfs_zap_caches_locked(struct inode *inode)
230 {
231 	struct nfs_inode *nfsi = NFS_I(inode);
232 	int mode = inode->i_mode;
233 
234 	nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
235 
236 	nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
237 	nfsi->attrtimeo_timestamp = jiffies;
238 
239 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))
240 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR |
241 						     NFS_INO_INVALID_DATA |
242 						     NFS_INO_INVALID_ACCESS |
243 						     NFS_INO_INVALID_ACL |
244 						     NFS_INO_INVALID_XATTR);
245 	else
246 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR |
247 						     NFS_INO_INVALID_ACCESS |
248 						     NFS_INO_INVALID_ACL |
249 						     NFS_INO_INVALID_XATTR);
250 	nfs_zap_label_cache_locked(nfsi);
251 }
252 
nfs_zap_caches(struct inode * inode)253 void nfs_zap_caches(struct inode *inode)
254 {
255 	spin_lock(&inode->i_lock);
256 	nfs_zap_caches_locked(inode);
257 	spin_unlock(&inode->i_lock);
258 }
259 
nfs_zap_mapping(struct inode * inode,struct address_space * mapping)260 void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
261 {
262 	if (mapping->nrpages != 0) {
263 		spin_lock(&inode->i_lock);
264 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
265 		spin_unlock(&inode->i_lock);
266 	}
267 }
268 
nfs_zap_acl_cache(struct inode * inode)269 void nfs_zap_acl_cache(struct inode *inode)
270 {
271 	void (*clear_acl_cache)(struct inode *);
272 
273 	clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
274 	if (clear_acl_cache != NULL)
275 		clear_acl_cache(inode);
276 	spin_lock(&inode->i_lock);
277 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
278 	spin_unlock(&inode->i_lock);
279 }
280 EXPORT_SYMBOL_GPL(nfs_zap_acl_cache);
281 
nfs_invalidate_atime(struct inode * inode)282 void nfs_invalidate_atime(struct inode *inode)
283 {
284 	if (nfs_have_delegated_atime(inode))
285 		return;
286 	spin_lock(&inode->i_lock);
287 	nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
288 	spin_unlock(&inode->i_lock);
289 }
290 EXPORT_SYMBOL_GPL(nfs_invalidate_atime);
291 
292 /*
293  * Invalidate, but do not unhash, the inode.
294  * NB: must be called with inode->i_lock held!
295  */
nfs_set_inode_stale_locked(struct inode * inode)296 static void nfs_set_inode_stale_locked(struct inode *inode)
297 {
298 	set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
299 	nfs_zap_caches_locked(inode);
300 	trace_nfs_set_inode_stale(inode);
301 }
302 
nfs_set_inode_stale(struct inode * inode)303 void nfs_set_inode_stale(struct inode *inode)
304 {
305 	spin_lock(&inode->i_lock);
306 	nfs_set_inode_stale_locked(inode);
307 	spin_unlock(&inode->i_lock);
308 }
309 
310 struct nfs_find_desc {
311 	struct nfs_fh		*fh;
312 	struct nfs_fattr	*fattr;
313 };
314 
315 /*
316  * In NFSv3 we can have 64bit inode numbers. In order to support
317  * this, and re-exported directories (also seen in NFSv2)
318  * we are forced to allow 2 different inodes to have the same
319  * i_ino.
320  */
321 static int
nfs_find_actor(struct inode * inode,void * opaque)322 nfs_find_actor(struct inode *inode, void *opaque)
323 {
324 	struct nfs_find_desc	*desc = opaque;
325 	struct nfs_fh		*fh = desc->fh;
326 	struct nfs_fattr	*fattr = desc->fattr;
327 
328 	if (NFS_FILEID(inode) != fattr->fileid)
329 		return 0;
330 	if (inode_wrong_type(inode, fattr->mode))
331 		return 0;
332 	if (nfs_compare_fh(NFS_FH(inode), fh))
333 		return 0;
334 	if (is_bad_inode(inode) || NFS_STALE(inode))
335 		return 0;
336 	return 1;
337 }
338 
339 static int
nfs_init_locked(struct inode * inode,void * opaque)340 nfs_init_locked(struct inode *inode, void *opaque)
341 {
342 	struct nfs_find_desc	*desc = opaque;
343 	struct nfs_fattr	*fattr = desc->fattr;
344 
345 	set_nfs_fileid(inode, fattr->fileid);
346 	inode->i_mode = fattr->mode;
347 	nfs_copy_fh(NFS_FH(inode), desc->fh);
348 	return 0;
349 }
350 
351 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
nfs_clear_label_invalid(struct inode * inode)352 static void nfs_clear_label_invalid(struct inode *inode)
353 {
354 	spin_lock(&inode->i_lock);
355 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_LABEL;
356 	spin_unlock(&inode->i_lock);
357 }
358 
nfs_setsecurity(struct inode * inode,struct nfs_fattr * fattr)359 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr)
360 {
361 	int error;
362 
363 	if (fattr->label == NULL)
364 		return;
365 
366 	if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
367 		error = security_inode_notifysecctx(inode, fattr->label->label,
368 				fattr->label->len);
369 		if (error)
370 			printk(KERN_ERR "%s() %s %d "
371 					"security_inode_notifysecctx() %d\n",
372 					__func__,
373 					(char *)fattr->label->label,
374 					fattr->label->len, error);
375 		nfs_clear_label_invalid(inode);
376 	}
377 }
378 
nfs4_label_alloc(struct nfs_server * server,gfp_t flags)379 struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
380 {
381 	struct nfs4_label *label;
382 
383 	if (!(server->caps & NFS_CAP_SECURITY_LABEL))
384 		return NULL;
385 
386 	label = kzalloc(sizeof(struct nfs4_label), flags);
387 	if (label == NULL)
388 		return ERR_PTR(-ENOMEM);
389 
390 	label->label = kzalloc(NFS4_MAXLABELLEN, flags);
391 	if (label->label == NULL) {
392 		kfree(label);
393 		return ERR_PTR(-ENOMEM);
394 	}
395 	label->len = NFS4_MAXLABELLEN;
396 
397 	return label;
398 }
399 EXPORT_SYMBOL_GPL(nfs4_label_alloc);
400 #else
nfs_setsecurity(struct inode * inode,struct nfs_fattr * fattr)401 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr)
402 {
403 }
404 #endif
405 EXPORT_SYMBOL_GPL(nfs_setsecurity);
406 
407 /* Search for inode identified by fh, fileid and i_mode in inode cache. */
408 struct inode *
nfs_ilookup(struct super_block * sb,struct nfs_fattr * fattr,struct nfs_fh * fh)409 nfs_ilookup(struct super_block *sb, struct nfs_fattr *fattr, struct nfs_fh *fh)
410 {
411 	struct nfs_find_desc desc = {
412 		.fh	= fh,
413 		.fattr	= fattr,
414 	};
415 	struct inode *inode;
416 	unsigned long hash;
417 
418 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID) ||
419 	    !(fattr->valid & NFS_ATTR_FATTR_TYPE))
420 		return NULL;
421 
422 	hash = nfs_fattr_to_ino_t(fattr);
423 	inode = ilookup5(sb, hash, nfs_find_actor, &desc);
424 
425 	dprintk("%s: returning %p\n", __func__, inode);
426 	return inode;
427 }
428 
nfs_inode_init_regular(struct nfs_inode * nfsi)429 static void nfs_inode_init_regular(struct nfs_inode *nfsi)
430 {
431 	atomic_long_set(&nfsi->nrequests, 0);
432 	atomic_long_set(&nfsi->redirtied_pages, 0);
433 	INIT_LIST_HEAD(&nfsi->commit_info.list);
434 	atomic_long_set(&nfsi->commit_info.ncommit, 0);
435 	atomic_set(&nfsi->commit_info.rpcs_out, 0);
436 	mutex_init(&nfsi->commit_mutex);
437 }
438 
nfs_inode_init_dir(struct nfs_inode * nfsi)439 static void nfs_inode_init_dir(struct nfs_inode *nfsi)
440 {
441 	nfsi->cache_change_attribute = 0;
442 	memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
443 	init_rwsem(&nfsi->rmdir_sem);
444 }
445 
446 /*
447  * This is our front-end to iget that looks up inodes by file handle
448  * instead of inode number.
449  */
450 struct inode *
nfs_fhget(struct super_block * sb,struct nfs_fh * fh,struct nfs_fattr * fattr)451 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
452 {
453 	struct nfs_find_desc desc = {
454 		.fh	= fh,
455 		.fattr	= fattr
456 	};
457 	struct inode *inode = ERR_PTR(-ENOENT);
458 	u64 fattr_supported = NFS_SB(sb)->fattr_valid;
459 	unsigned long hash;
460 
461 	nfs_attr_check_mountpoint(sb, fattr);
462 
463 	if (nfs_attr_use_mounted_on_fileid(fattr))
464 		fattr->fileid = fattr->mounted_on_fileid;
465 	else if ((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0)
466 		goto out_no_inode;
467 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
468 		goto out_no_inode;
469 
470 	hash = nfs_fattr_to_ino_t(fattr);
471 
472 	inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
473 	if (inode == NULL) {
474 		inode = ERR_PTR(-ENOMEM);
475 		goto out_no_inode;
476 	}
477 
478 	if (inode->i_state & I_NEW) {
479 		struct nfs_inode *nfsi = NFS_I(inode);
480 		unsigned long now = jiffies;
481 
482 		/* We set i_ino for the few things that still rely on it,
483 		 * such as stat(2) */
484 		inode->i_ino = hash;
485 
486 		/* We can't support update_atime(), since the server will reset it */
487 		inode->i_flags |= S_NOATIME|S_NOCMTIME;
488 		inode->i_mode = fattr->mode;
489 		nfsi->cache_validity = 0;
490 		if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
491 				&& (fattr_supported & NFS_ATTR_FATTR_MODE))
492 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MODE);
493 		/* Why so? Because we want revalidate for devices/FIFOs, and
494 		 * that's precisely what we have in nfs_file_inode_operations.
495 		 */
496 		inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
497 		if (S_ISREG(inode->i_mode)) {
498 			inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
499 			inode->i_data.a_ops = &nfs_file_aops;
500 			nfs_inode_init_regular(nfsi);
501 			mapping_set_large_folios(inode->i_mapping);
502 		} else if (S_ISDIR(inode->i_mode)) {
503 			inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
504 			inode->i_fop = &nfs_dir_operations;
505 			inode->i_data.a_ops = &nfs_dir_aops;
506 			nfs_inode_init_dir(nfsi);
507 			/* Deal with crossing mountpoints */
508 			if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
509 					fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
510 				if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
511 					inode->i_op = &nfs_referral_inode_operations;
512 				else
513 					inode->i_op = &nfs_mountpoint_inode_operations;
514 				inode->i_fop = NULL;
515 				inode->i_flags |= S_AUTOMOUNT;
516 			}
517 		} else if (S_ISLNK(inode->i_mode)) {
518 			inode->i_op = &nfs_symlink_inode_operations;
519 			inode_nohighmem(inode);
520 		} else
521 			init_special_inode(inode, inode->i_mode, fattr->rdev);
522 
523 		inode_set_atime(inode, 0, 0);
524 		inode_set_mtime(inode, 0, 0);
525 		inode_set_ctime(inode, 0, 0);
526 		memset(&nfsi->btime, 0, sizeof(nfsi->btime));
527 		inode_set_iversion_raw(inode, 0);
528 		inode->i_size = 0;
529 		clear_nlink(inode);
530 		inode->i_uid = make_kuid(&init_user_ns, -2);
531 		inode->i_gid = make_kgid(&init_user_ns, -2);
532 		inode->i_blocks = 0;
533 		nfsi->write_io = 0;
534 		nfsi->read_io = 0;
535 
536 		nfsi->read_cache_jiffies = fattr->time_start;
537 		nfsi->attr_gencount = fattr->gencount;
538 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
539 			inode_set_atime_to_ts(inode, fattr->atime);
540 		else if (fattr_supported & NFS_ATTR_FATTR_ATIME)
541 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
542 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
543 			inode_set_mtime_to_ts(inode, fattr->mtime);
544 		else if (fattr_supported & NFS_ATTR_FATTR_MTIME)
545 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
546 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
547 			inode_set_ctime_to_ts(inode, fattr->ctime);
548 		else if (fattr_supported & NFS_ATTR_FATTR_CTIME)
549 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CTIME);
550 		if (fattr->valid & NFS_ATTR_FATTR_BTIME)
551 			nfsi->btime = fattr->btime;
552 		else if (fattr_supported & NFS_ATTR_FATTR_BTIME)
553 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_BTIME);
554 		if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
555 			inode_set_iversion_raw(inode, fattr->change_attr);
556 		else
557 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE);
558 		if (fattr->valid & NFS_ATTR_FATTR_SIZE)
559 			inode->i_size = nfs_size_to_loff_t(fattr->size);
560 		else
561 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_SIZE);
562 		if (fattr->valid & NFS_ATTR_FATTR_NLINK)
563 			set_nlink(inode, fattr->nlink);
564 		else if (fattr_supported & NFS_ATTR_FATTR_NLINK)
565 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_NLINK);
566 		else
567 			set_nlink(inode, 1);
568 		if (fattr->valid & NFS_ATTR_FATTR_OWNER)
569 			inode->i_uid = fattr->uid;
570 		else if (fattr_supported & NFS_ATTR_FATTR_OWNER)
571 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
572 		if (fattr->valid & NFS_ATTR_FATTR_GROUP)
573 			inode->i_gid = fattr->gid;
574 		else if (fattr_supported & NFS_ATTR_FATTR_GROUP)
575 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
576 		if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
577 			inode->i_blocks = fattr->du.nfs2.blocks;
578 		else if (fattr_supported & NFS_ATTR_FATTR_BLOCKS_USED &&
579 			 fattr->size != 0)
580 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_BLOCKS);
581 		if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
582 			/*
583 			 * report the blocks in 512byte units
584 			 */
585 			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
586 		} else if (fattr_supported & NFS_ATTR_FATTR_SPACE_USED &&
587 			   fattr->size != 0)
588 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_BLOCKS);
589 
590 		nfs_setsecurity(inode, fattr);
591 
592 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
593 		nfsi->attrtimeo_timestamp = now;
594 		nfsi->access_cache = RB_ROOT;
595 
596 		nfs_fscache_init_inode(inode);
597 
598 		unlock_new_inode(inode);
599 	} else {
600 		int err = nfs_refresh_inode(inode, fattr);
601 		if (err < 0) {
602 			iput(inode);
603 			inode = ERR_PTR(err);
604 			goto out_no_inode;
605 		}
606 	}
607 	dprintk("NFS: nfs_fhget(%s/%Lu fh_crc=0x%08x ct=%d)\n",
608 		inode->i_sb->s_id,
609 		(unsigned long long)NFS_FILEID(inode),
610 		nfs_display_fhandle_hash(fh),
611 		icount_read(inode));
612 
613 out:
614 	return inode;
615 
616 out_no_inode:
617 	dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
618 	goto out;
619 }
620 EXPORT_SYMBOL_GPL(nfs_fhget);
621 
622 static void
nfs_fattr_fixup_delegated(struct inode * inode,struct nfs_fattr * fattr)623 nfs_fattr_fixup_delegated(struct inode *inode, struct nfs_fattr *fattr)
624 {
625 	unsigned long cache_validity = NFS_I(inode)->cache_validity;
626 
627 	if (nfs_have_delegated_mtime(inode)) {
628 		if (!(cache_validity & NFS_INO_INVALID_CTIME))
629 			fattr->valid &= ~(NFS_ATTR_FATTR_PRECTIME |
630 					  NFS_ATTR_FATTR_CTIME);
631 
632 		if (!(cache_validity & NFS_INO_INVALID_MTIME))
633 			fattr->valid &= ~(NFS_ATTR_FATTR_PREMTIME |
634 					  NFS_ATTR_FATTR_MTIME);
635 
636 		if (!(cache_validity & NFS_INO_INVALID_ATIME))
637 			fattr->valid &= ~NFS_ATTR_FATTR_ATIME;
638 	} else if (nfs_have_delegated_atime(inode)) {
639 		if (!(cache_validity & NFS_INO_INVALID_ATIME))
640 			fattr->valid &= ~NFS_ATTR_FATTR_ATIME;
641 	}
642 }
643 
nfs_set_timestamps_to_ts(struct inode * inode,struct iattr * attr)644 static void nfs_set_timestamps_to_ts(struct inode *inode, struct iattr *attr)
645 {
646 	unsigned int cache_flags = 0;
647 
648 	if (attr->ia_valid & ATTR_MTIME_SET) {
649 		struct timespec64 ctime = inode_get_ctime(inode);
650 		struct timespec64 mtime = inode_get_mtime(inode);
651 		struct timespec64 now;
652 		int updated = 0;
653 
654 		now = inode_set_ctime_current(inode);
655 		if (!timespec64_equal(&now, &ctime))
656 			updated |= S_CTIME;
657 
658 		inode_set_mtime_to_ts(inode, attr->ia_mtime);
659 		if (!timespec64_equal(&now, &mtime))
660 			updated |= S_MTIME;
661 
662 		inode_maybe_inc_iversion(inode, updated);
663 		cache_flags |= NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME;
664 	}
665 	if (attr->ia_valid & ATTR_ATIME_SET) {
666 		inode_set_atime_to_ts(inode, attr->ia_atime);
667 		cache_flags |= NFS_INO_INVALID_ATIME;
668 	}
669 	NFS_I(inode)->cache_validity &= ~cache_flags;
670 }
671 
nfs_update_timestamps(struct inode * inode,unsigned int ia_valid)672 static void nfs_update_timestamps(struct inode *inode, unsigned int ia_valid)
673 {
674 	enum file_time_flags time_flags = 0;
675 	unsigned int cache_flags = 0;
676 
677 	if (ia_valid & ATTR_MTIME) {
678 		time_flags |= S_MTIME | S_CTIME;
679 		cache_flags |= NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME;
680 	}
681 	if (ia_valid & ATTR_ATIME) {
682 		time_flags |= S_ATIME;
683 		cache_flags |= NFS_INO_INVALID_ATIME;
684 	}
685 	inode_update_timestamps(inode, time_flags);
686 	NFS_I(inode)->cache_validity &= ~cache_flags;
687 }
688 
nfs_update_delegated_atime(struct inode * inode)689 void nfs_update_delegated_atime(struct inode *inode)
690 {
691 	spin_lock(&inode->i_lock);
692 	if (nfs_have_delegated_atime(inode))
693 		nfs_update_timestamps(inode, ATTR_ATIME);
694 	spin_unlock(&inode->i_lock);
695 }
696 
nfs_update_delegated_mtime_locked(struct inode * inode)697 void nfs_update_delegated_mtime_locked(struct inode *inode)
698 {
699 	if (nfs_have_delegated_mtime(inode))
700 		nfs_update_timestamps(inode, ATTR_MTIME);
701 }
702 
nfs_update_delegated_mtime(struct inode * inode)703 void nfs_update_delegated_mtime(struct inode *inode)
704 {
705 	spin_lock(&inode->i_lock);
706 	nfs_update_delegated_mtime_locked(inode);
707 	spin_unlock(&inode->i_lock);
708 }
709 EXPORT_SYMBOL_GPL(nfs_update_delegated_mtime);
710 
711 #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)
712 
713 int
nfs_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * attr)714 nfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
715 	    struct iattr *attr)
716 {
717 	struct inode *inode = d_inode(dentry);
718 	struct nfs_fattr *fattr;
719 	loff_t oldsize = i_size_read(inode);
720 	int error = 0;
721 
722 	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
723 
724 	/* skip mode change if it's just for clearing setuid/setgid */
725 	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
726 		attr->ia_valid &= ~ATTR_MODE;
727 
728 	if (attr->ia_valid & ATTR_SIZE) {
729 		BUG_ON(!S_ISREG(inode->i_mode));
730 
731 		error = inode_newsize_ok(inode, attr->ia_size);
732 		if (error)
733 			return error;
734 
735 		if (attr->ia_size == oldsize)
736 			attr->ia_valid &= ~ATTR_SIZE;
737 	}
738 
739 	if (nfs_have_delegated_mtime(inode) && attr->ia_valid & ATTR_MTIME) {
740 		spin_lock(&inode->i_lock);
741 		if (attr->ia_valid & ATTR_MTIME_SET) {
742 			nfs_set_timestamps_to_ts(inode, attr);
743 			attr->ia_valid &= ~(ATTR_MTIME|ATTR_MTIME_SET|
744 						ATTR_ATIME|ATTR_ATIME_SET);
745 		} else {
746 			nfs_update_timestamps(inode, attr->ia_valid);
747 			attr->ia_valid &= ~(ATTR_MTIME|ATTR_ATIME);
748 		}
749 		spin_unlock(&inode->i_lock);
750 	} else if (nfs_have_delegated_atime(inode) &&
751 		   attr->ia_valid & ATTR_ATIME &&
752 		   !(attr->ia_valid & ATTR_MTIME)) {
753 		if (attr->ia_valid & ATTR_ATIME_SET) {
754 			spin_lock(&inode->i_lock);
755 			nfs_set_timestamps_to_ts(inode, attr);
756 			spin_unlock(&inode->i_lock);
757 			attr->ia_valid &= ~(ATTR_ATIME|ATTR_ATIME_SET);
758 		} else {
759 			nfs_update_delegated_atime(inode);
760 			attr->ia_valid &= ~ATTR_ATIME;
761 		}
762 	}
763 
764 	/* Optimization: if the end result is no change, don't RPC */
765 	if (((attr->ia_valid & NFS_VALID_ATTRS) & ~(ATTR_FILE|ATTR_OPEN)) == 0)
766 		return 0;
767 
768 	trace_nfs_setattr_enter(inode);
769 
770 	/* Write all dirty data */
771 	if (S_ISREG(inode->i_mode)) {
772 		nfs_file_block_o_direct(NFS_I(inode));
773 		nfs_sync_inode(inode);
774 	}
775 
776 	fattr = nfs_alloc_fattr_with_label(NFS_SERVER(inode));
777 	if (fattr == NULL) {
778 		error = -ENOMEM;
779 		goto out;
780 	}
781 
782 	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
783 	if (error == 0) {
784 		if (attr->ia_valid & ATTR_SIZE)
785 			nfs_truncate_last_folio(inode->i_mapping, oldsize,
786 						attr->ia_size);
787 		error = nfs_refresh_inode(inode, fattr);
788 	}
789 	nfs_free_fattr(fattr);
790 out:
791 	trace_nfs_setattr_exit(inode, error);
792 	return error;
793 }
794 EXPORT_SYMBOL_GPL(nfs_setattr);
795 
796 /**
797  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
798  * @inode: inode of the file used
799  * @offset: file offset to start truncating
800  *
801  * This is a copy of the common vmtruncate, but with the locking
802  * corrected to take into account the fact that NFS requires
803  * inode->i_size to be updated under the inode->i_lock.
804  * Note: must be called with inode->i_lock held!
805  */
nfs_vmtruncate(struct inode * inode,loff_t offset)806 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
807 {
808 	int err;
809 
810 	err = inode_newsize_ok(inode, offset);
811 	if (err)
812 		goto out;
813 
814 	trace_nfs_size_truncate(inode, offset);
815 	i_size_write(inode, offset);
816 	/* Optimisation */
817 	if (offset == 0) {
818 		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA;
819 		nfs_ooo_clear(NFS_I(inode));
820 	}
821 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE;
822 
823 	spin_unlock(&inode->i_lock);
824 	truncate_pagecache(inode, offset);
825 	nfs_update_delegated_mtime_locked(inode);
826 	spin_lock(&inode->i_lock);
827 out:
828 	return err;
829 }
830 
831 /**
832  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
833  * @inode: pointer to struct inode
834  * @attr: pointer to struct iattr
835  * @fattr: pointer to struct nfs_fattr
836  *
837  * Note: we do this in the *proc.c in order to ensure that
838  *       it works for things like exclusive creates too.
839  */
nfs_setattr_update_inode(struct inode * inode,struct iattr * attr,struct nfs_fattr * fattr)840 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr,
841 		struct nfs_fattr *fattr)
842 {
843 	/* Barrier: bump the attribute generation count. */
844 	nfs_fattr_set_barrier(fattr);
845 
846 	spin_lock(&inode->i_lock);
847 	NFS_I(inode)->attr_gencount = fattr->gencount;
848 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
849 		if (!nfs_have_delegated_mtime(inode))
850 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
851 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_BLOCKS);
852 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
853 		nfs_vmtruncate(inode, attr->ia_size);
854 	}
855 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
856 		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_CTIME;
857 		if ((attr->ia_valid & ATTR_KILL_SUID) != 0 &&
858 		    inode->i_mode & S_ISUID)
859 			inode->i_mode &= ~S_ISUID;
860 		if (setattr_should_drop_sgid(&nop_mnt_idmap, inode))
861 			inode->i_mode &= ~S_ISGID;
862 		if ((attr->ia_valid & ATTR_MODE) != 0) {
863 			int mode = attr->ia_mode & S_IALLUGO;
864 			mode |= inode->i_mode & ~S_IALLUGO;
865 			inode->i_mode = mode;
866 		}
867 		if ((attr->ia_valid & ATTR_UID) != 0)
868 			inode->i_uid = attr->ia_uid;
869 		if ((attr->ia_valid & ATTR_GID) != 0)
870 			inode->i_gid = attr->ia_gid;
871 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
872 			inode_set_ctime_to_ts(inode, fattr->ctime);
873 		else
874 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
875 					| NFS_INO_INVALID_CTIME);
876 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS
877 				| NFS_INO_INVALID_ACL);
878 	}
879 	if (attr->ia_valid & (ATTR_ATIME_SET|ATTR_ATIME)) {
880 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_ATIME
881 				| NFS_INO_INVALID_CTIME);
882 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
883 			inode_set_atime_to_ts(inode, fattr->atime);
884 		else if (attr->ia_valid & ATTR_ATIME_SET)
885 			inode_set_atime_to_ts(inode, attr->ia_atime);
886 		else
887 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
888 
889 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
890 			inode_set_ctime_to_ts(inode, fattr->ctime);
891 		else
892 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
893 					| NFS_INO_INVALID_CTIME);
894 	}
895 	if (attr->ia_valid & (ATTR_MTIME_SET|ATTR_MTIME)) {
896 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_MTIME
897 				| NFS_INO_INVALID_CTIME);
898 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
899 			inode_set_mtime_to_ts(inode, fattr->mtime);
900 		else if (attr->ia_valid & ATTR_MTIME_SET)
901 			inode_set_mtime_to_ts(inode, attr->ia_mtime);
902 		else
903 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
904 
905 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
906 			inode_set_ctime_to_ts(inode, fattr->ctime);
907 		else
908 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
909 					| NFS_INO_INVALID_CTIME);
910 	}
911 	if (fattr->valid)
912 		nfs_update_inode(inode, fattr);
913 	spin_unlock(&inode->i_lock);
914 }
915 EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
916 
917 /*
918  * Don't request help from readdirplus if the file is being written to,
919  * or if attribute caching is turned off
920  */
nfs_getattr_readdirplus_enable(const struct inode * inode)921 static bool nfs_getattr_readdirplus_enable(const struct inode *inode)
922 {
923 	return nfs_server_capable(inode, NFS_CAP_READDIRPLUS) &&
924 	       !nfs_have_writebacks(inode) && NFS_MAXATTRTIMEO(inode) > 5 * HZ;
925 }
926 
nfs_readdirplus_parent_cache_miss(struct dentry * dentry)927 static void nfs_readdirplus_parent_cache_miss(struct dentry *dentry)
928 {
929 	if (!IS_ROOT(dentry)) {
930 		struct dentry *parent = dget_parent(dentry);
931 		nfs_readdir_record_entry_cache_miss(d_inode(parent));
932 		dput(parent);
933 	}
934 }
935 
nfs_readdirplus_parent_cache_hit(struct dentry * dentry)936 static void nfs_readdirplus_parent_cache_hit(struct dentry *dentry)
937 {
938 	if (!IS_ROOT(dentry)) {
939 		struct dentry *parent = dget_parent(dentry);
940 		nfs_readdir_record_entry_cache_hit(d_inode(parent));
941 		dput(parent);
942 	}
943 }
944 
nfs_get_valid_attrmask(struct inode * inode)945 static u32 nfs_get_valid_attrmask(struct inode *inode)
946 {
947 	u64 fattr_valid = NFS_SERVER(inode)->fattr_valid;
948 	unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
949 	u32 reply_mask = STATX_INO | STATX_TYPE;
950 
951 	if (!(cache_validity & NFS_INO_INVALID_ATIME))
952 		reply_mask |= STATX_ATIME;
953 	if (!(cache_validity & NFS_INO_INVALID_CTIME))
954 		reply_mask |= STATX_CTIME;
955 	if (!(cache_validity & NFS_INO_INVALID_MTIME))
956 		reply_mask |= STATX_MTIME;
957 	if (!(cache_validity & NFS_INO_INVALID_SIZE))
958 		reply_mask |= STATX_SIZE;
959 	if (!(cache_validity & NFS_INO_INVALID_NLINK))
960 		reply_mask |= STATX_NLINK;
961 	if (!(cache_validity & NFS_INO_INVALID_MODE))
962 		reply_mask |= STATX_MODE;
963 	if (!(cache_validity & NFS_INO_INVALID_OTHER))
964 		reply_mask |= STATX_UID | STATX_GID;
965 	if (!(cache_validity & NFS_INO_INVALID_BLOCKS))
966 		reply_mask |= STATX_BLOCKS;
967 	if (!(cache_validity & NFS_INO_INVALID_BTIME) &&
968 	    (fattr_valid & NFS_ATTR_FATTR_BTIME))
969 		reply_mask |= STATX_BTIME;
970 	if (!(cache_validity & NFS_INO_INVALID_CHANGE))
971 		reply_mask |= STATX_CHANGE_COOKIE;
972 	return reply_mask;
973 }
974 
nfs_getattr(struct mnt_idmap * idmap,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)975 int nfs_getattr(struct mnt_idmap *idmap, const struct path *path,
976 		struct kstat *stat, u32 request_mask, unsigned int query_flags)
977 {
978 	struct inode *inode = d_inode(path->dentry);
979 	struct nfs_server *server = NFS_SERVER(inode);
980 	u64 fattr_valid = server->fattr_valid;
981 	unsigned long cache_validity;
982 	int err = 0;
983 	bool force_sync = query_flags & AT_STATX_FORCE_SYNC;
984 	bool do_update = false;
985 	bool readdirplus_enabled = nfs_getattr_readdirplus_enable(inode);
986 
987 	trace_nfs_getattr_enter(inode);
988 
989 	request_mask &= STATX_TYPE | STATX_MODE | STATX_NLINK | STATX_UID |
990 			STATX_GID | STATX_ATIME | STATX_MTIME | STATX_CTIME |
991 			STATX_INO | STATX_SIZE | STATX_BLOCKS | STATX_BTIME |
992 			STATX_CHANGE_COOKIE;
993 
994 	if (!(fattr_valid & NFS_ATTR_FATTR_BTIME))
995 		request_mask &= ~STATX_BTIME;
996 
997 	if ((query_flags & AT_STATX_DONT_SYNC) && !force_sync) {
998 		if (readdirplus_enabled)
999 			nfs_readdirplus_parent_cache_hit(path->dentry);
1000 		goto out_no_revalidate;
1001 	}
1002 
1003 	/* Flush out writes to the server in order to update c/mtime/version.  */
1004 	if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_CHANGE_COOKIE)) &&
1005 	    S_ISREG(inode->i_mode)) {
1006 		if (nfs_have_delegated_mtime(inode))
1007 			filemap_fdatawrite(inode->i_mapping);
1008 		else
1009 			filemap_write_and_wait(inode->i_mapping);
1010 	}
1011 
1012 	/*
1013 	 * We may force a getattr if the user cares about atime.
1014 	 *
1015 	 * Note that we only have to check the vfsmount flags here:
1016 	 *  - NFS always sets S_NOATIME by so checking it would give a
1017 	 *    bogus result
1018 	 *  - NFS never sets SB_NOATIME or SB_NODIRATIME so there is
1019 	 *    no point in checking those.
1020 	 */
1021 	if ((path->mnt->mnt_flags & MNT_NOATIME) ||
1022 	    ((path->mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
1023 		request_mask &= ~STATX_ATIME;
1024 
1025 	/* Is the user requesting attributes that might need revalidation? */
1026 	if (!(request_mask & (STATX_MODE|STATX_NLINK|STATX_ATIME|STATX_CTIME|
1027 					STATX_MTIME|STATX_UID|STATX_GID|
1028 					STATX_SIZE|STATX_BLOCKS|STATX_BTIME|
1029 					STATX_CHANGE_COOKIE)))
1030 		goto out_no_revalidate;
1031 
1032 	/* Check whether the cached attributes are stale */
1033 	do_update |= force_sync || nfs_attribute_cache_expired(inode);
1034 	cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
1035 	do_update |= cache_validity & NFS_INO_INVALID_CHANGE;
1036 	if (request_mask & STATX_ATIME)
1037 		do_update |= cache_validity & NFS_INO_INVALID_ATIME;
1038 	if (request_mask & STATX_CTIME)
1039 		do_update |= cache_validity & NFS_INO_INVALID_CTIME;
1040 	if (request_mask & STATX_MTIME)
1041 		do_update |= cache_validity & NFS_INO_INVALID_MTIME;
1042 	if (request_mask & STATX_SIZE)
1043 		do_update |= cache_validity & NFS_INO_INVALID_SIZE;
1044 	if (request_mask & STATX_NLINK)
1045 		do_update |= cache_validity & NFS_INO_INVALID_NLINK;
1046 	if (request_mask & STATX_MODE)
1047 		do_update |= cache_validity & NFS_INO_INVALID_MODE;
1048 	if (request_mask & (STATX_UID | STATX_GID))
1049 		do_update |= cache_validity & NFS_INO_INVALID_OTHER;
1050 	if (request_mask & STATX_BLOCKS)
1051 		do_update |= cache_validity & NFS_INO_INVALID_BLOCKS;
1052 	if (request_mask & STATX_BTIME)
1053 		do_update |= cache_validity & NFS_INO_INVALID_BTIME;
1054 
1055 	if (do_update) {
1056 		if (readdirplus_enabled)
1057 			nfs_readdirplus_parent_cache_miss(path->dentry);
1058 		err = __nfs_revalidate_inode(server, inode);
1059 		if (err)
1060 			goto out;
1061 	} else if (readdirplus_enabled)
1062 		nfs_readdirplus_parent_cache_hit(path->dentry);
1063 out_no_revalidate:
1064 	/* Only return attributes that were revalidated. */
1065 	stat->result_mask = nfs_get_valid_attrmask(inode) | request_mask;
1066 
1067 	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
1068 	stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
1069 	stat->change_cookie = inode_peek_iversion_raw(inode);
1070 	stat->attributes_mask |= STATX_ATTR_CHANGE_MONOTONIC;
1071 	if (server->change_attr_type != NFS4_CHANGE_TYPE_IS_UNDEFINED)
1072 		stat->attributes |= STATX_ATTR_CHANGE_MONOTONIC;
1073 	if (S_ISDIR(inode->i_mode))
1074 		stat->blksize = NFS_SERVER(inode)->dtsize;
1075 	stat->btime = NFS_I(inode)->btime;
1076 
1077 	/* Special handling for STATX_DIOALIGN and STATX_DIO_READ_ALIGN
1078 	 * - NFS doesn't have DIO alignment constraints, avoid getting
1079 	 *   these DIO attrs from remote and just respond with most
1080 	 *   accommodating limits (so client will issue supported DIO).
1081 	 * - this is unintuitive, but the most coarse-grained
1082 	 *   dio_offset_align is the most accommodating.
1083 	 */
1084 	if ((request_mask & (STATX_DIOALIGN | STATX_DIO_READ_ALIGN)) &&
1085 	    S_ISREG(inode->i_mode)) {
1086 		stat->result_mask |= STATX_DIOALIGN | STATX_DIO_READ_ALIGN;
1087 		stat->dio_mem_align = 4; /* 4-byte alignment */
1088 		stat->dio_offset_align = PAGE_SIZE;
1089 		stat->dio_read_offset_align = stat->dio_offset_align;
1090 	}
1091 out:
1092 	trace_nfs_getattr_exit(inode, err);
1093 	return err;
1094 }
1095 EXPORT_SYMBOL_GPL(nfs_getattr);
1096 
nfs_init_lock_context(struct nfs_lock_context * l_ctx)1097 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
1098 {
1099 	refcount_set(&l_ctx->count, 1);
1100 	l_ctx->lockowner = current->files;
1101 	INIT_LIST_HEAD(&l_ctx->list);
1102 	atomic_set(&l_ctx->io_count, 0);
1103 }
1104 
__nfs_find_lock_context(struct nfs_open_context * ctx)1105 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
1106 {
1107 	struct nfs_lock_context *pos;
1108 
1109 	list_for_each_entry_rcu(pos, &ctx->lock_context.list, list) {
1110 		if (pos->lockowner != current->files)
1111 			continue;
1112 		if (refcount_inc_not_zero(&pos->count))
1113 			return pos;
1114 	}
1115 	return NULL;
1116 }
1117 
nfs_get_lock_context(struct nfs_open_context * ctx)1118 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
1119 {
1120 	struct nfs_lock_context *res, *new = NULL;
1121 	struct inode *inode = d_inode(ctx->dentry);
1122 
1123 	rcu_read_lock();
1124 	res = __nfs_find_lock_context(ctx);
1125 	rcu_read_unlock();
1126 	if (res == NULL) {
1127 		new = kmalloc(sizeof(*new), GFP_KERNEL_ACCOUNT);
1128 		if (new == NULL)
1129 			return ERR_PTR(-ENOMEM);
1130 		nfs_init_lock_context(new);
1131 		spin_lock(&inode->i_lock);
1132 		res = __nfs_find_lock_context(ctx);
1133 		if (res == NULL) {
1134 			new->open_context = get_nfs_open_context(ctx);
1135 			if (new->open_context) {
1136 				list_add_tail_rcu(&new->list,
1137 						&ctx->lock_context.list);
1138 				res = new;
1139 				new = NULL;
1140 			} else
1141 				res = ERR_PTR(-EBADF);
1142 		}
1143 		spin_unlock(&inode->i_lock);
1144 		kfree(new);
1145 	}
1146 	return res;
1147 }
1148 EXPORT_SYMBOL_GPL(nfs_get_lock_context);
1149 
nfs_put_lock_context(struct nfs_lock_context * l_ctx)1150 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
1151 {
1152 	struct nfs_open_context *ctx = l_ctx->open_context;
1153 	struct inode *inode = d_inode(ctx->dentry);
1154 
1155 	if (!refcount_dec_and_lock(&l_ctx->count, &inode->i_lock))
1156 		return;
1157 	list_del_rcu(&l_ctx->list);
1158 	spin_unlock(&inode->i_lock);
1159 	put_nfs_open_context(ctx);
1160 	kfree_rcu(l_ctx, rcu_head);
1161 }
1162 EXPORT_SYMBOL_GPL(nfs_put_lock_context);
1163 
1164 /**
1165  * nfs_close_context - Common close_context() routine NFSv2/v3
1166  * @ctx: pointer to context
1167  * @is_sync: is this a synchronous close
1168  *
1169  * Ensure that the attributes are up to date if we're mounted
1170  * with close-to-open semantics and we have cached data that will
1171  * need to be revalidated on open.
1172  */
nfs_close_context(struct nfs_open_context * ctx,int is_sync)1173 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
1174 {
1175 	struct nfs_inode *nfsi;
1176 	struct inode *inode;
1177 
1178 	if (!(ctx->mode & FMODE_WRITE))
1179 		return;
1180 	if (!is_sync)
1181 		return;
1182 	inode = d_inode(ctx->dentry);
1183 	if (nfs_have_read_or_write_delegation(inode))
1184 		return;
1185 	nfsi = NFS_I(inode);
1186 	if (inode->i_mapping->nrpages == 0)
1187 		return;
1188 	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1189 		return;
1190 	if (!list_empty(&nfsi->open_files))
1191 		return;
1192 	if (NFS_SERVER(inode)->flags & NFS_MOUNT_NOCTO)
1193 		return;
1194 	nfs_revalidate_inode(inode,
1195 			     NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_SIZE);
1196 }
1197 EXPORT_SYMBOL_GPL(nfs_close_context);
1198 
alloc_nfs_open_context(struct dentry * dentry,fmode_t f_mode,struct file * filp)1199 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry,
1200 						fmode_t f_mode,
1201 						struct file *filp)
1202 {
1203 	struct nfs_open_context *ctx;
1204 
1205 	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL_ACCOUNT);
1206 	if (!ctx)
1207 		return ERR_PTR(-ENOMEM);
1208 	nfs_sb_active(dentry->d_sb);
1209 	ctx->dentry = dget(dentry);
1210 	if (filp)
1211 		ctx->cred = get_cred(filp->f_cred);
1212 	else
1213 		ctx->cred = get_current_cred();
1214 	rcu_assign_pointer(ctx->ll_cred, NULL);
1215 	ctx->state = NULL;
1216 	ctx->mode = f_mode;
1217 	ctx->flags = 0;
1218 	ctx->error = 0;
1219 	ctx->flock_owner = (fl_owner_t)filp;
1220 	nfs_init_lock_context(&ctx->lock_context);
1221 	ctx->lock_context.open_context = ctx;
1222 	INIT_LIST_HEAD(&ctx->list);
1223 	ctx->mdsthreshold = NULL;
1224 	nfs_localio_file_init(&ctx->nfl);
1225 
1226 	return ctx;
1227 }
1228 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
1229 
get_nfs_open_context(struct nfs_open_context * ctx)1230 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
1231 {
1232 	if (ctx != NULL && refcount_inc_not_zero(&ctx->lock_context.count))
1233 		return ctx;
1234 	return NULL;
1235 }
1236 EXPORT_SYMBOL_GPL(get_nfs_open_context);
1237 
__put_nfs_open_context(struct nfs_open_context * ctx,int is_sync)1238 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
1239 {
1240 	struct inode *inode = d_inode(ctx->dentry);
1241 	struct super_block *sb = ctx->dentry->d_sb;
1242 
1243 	if (!refcount_dec_and_test(&ctx->lock_context.count))
1244 		return;
1245 	if (!list_empty(&ctx->list)) {
1246 		spin_lock(&inode->i_lock);
1247 		list_del_rcu(&ctx->list);
1248 		spin_unlock(&inode->i_lock);
1249 	}
1250 	if (inode != NULL)
1251 		NFS_PROTO(inode)->close_context(ctx, is_sync);
1252 	put_cred(ctx->cred);
1253 	dput(ctx->dentry);
1254 	nfs_sb_deactive(sb);
1255 	put_rpccred(rcu_dereference_protected(ctx->ll_cred, 1));
1256 	kfree(ctx->mdsthreshold);
1257 	nfs_close_local_fh(&ctx->nfl);
1258 	kfree_rcu(ctx, rcu_head);
1259 }
1260 
put_nfs_open_context(struct nfs_open_context * ctx)1261 void put_nfs_open_context(struct nfs_open_context *ctx)
1262 {
1263 	__put_nfs_open_context(ctx, 0);
1264 }
1265 EXPORT_SYMBOL_GPL(put_nfs_open_context);
1266 
put_nfs_open_context_sync(struct nfs_open_context * ctx)1267 static void put_nfs_open_context_sync(struct nfs_open_context *ctx)
1268 {
1269 	__put_nfs_open_context(ctx, 1);
1270 }
1271 
1272 /*
1273  * Ensure that mmap has a recent RPC credential for use when writing out
1274  * shared pages
1275  */
nfs_inode_attach_open_context(struct nfs_open_context * ctx)1276 void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
1277 {
1278 	struct inode *inode = d_inode(ctx->dentry);
1279 	struct nfs_inode *nfsi = NFS_I(inode);
1280 
1281 	spin_lock(&inode->i_lock);
1282 	if (list_empty(&nfsi->open_files) &&
1283 	    nfs_ooo_test(nfsi))
1284 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA |
1285 						     NFS_INO_REVAL_FORCED);
1286 	list_add_tail_rcu(&ctx->list, &nfsi->open_files);
1287 	spin_unlock(&inode->i_lock);
1288 }
1289 EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
1290 
nfs_file_set_open_context(struct file * filp,struct nfs_open_context * ctx)1291 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
1292 {
1293 	filp->private_data = get_nfs_open_context(ctx);
1294 	set_bit(NFS_CONTEXT_FILE_OPEN, &ctx->flags);
1295 	if (list_empty(&ctx->list))
1296 		nfs_inode_attach_open_context(ctx);
1297 }
1298 EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
1299 
1300 /*
1301  * Given an inode, search for an open context with the desired characteristics
1302  */
nfs_find_open_context(struct inode * inode,const struct cred * cred,fmode_t mode)1303 struct nfs_open_context *nfs_find_open_context(struct inode *inode, const struct cred *cred, fmode_t mode)
1304 {
1305 	struct nfs_inode *nfsi = NFS_I(inode);
1306 	struct nfs_open_context *pos, *ctx = NULL;
1307 
1308 	rcu_read_lock();
1309 	list_for_each_entry_rcu(pos, &nfsi->open_files, list) {
1310 		if (cred != NULL && cred_fscmp(pos->cred, cred) != 0)
1311 			continue;
1312 		if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
1313 			continue;
1314 		if (!test_bit(NFS_CONTEXT_FILE_OPEN, &pos->flags))
1315 			continue;
1316 		ctx = get_nfs_open_context(pos);
1317 		if (ctx)
1318 			break;
1319 	}
1320 	rcu_read_unlock();
1321 	return ctx;
1322 }
1323 
nfs_file_clear_open_context(struct file * filp)1324 void nfs_file_clear_open_context(struct file *filp)
1325 {
1326 	struct nfs_open_context *ctx = nfs_file_open_context(filp);
1327 
1328 	if (ctx) {
1329 		struct inode *inode = d_inode(ctx->dentry);
1330 
1331 		clear_bit(NFS_CONTEXT_FILE_OPEN, &ctx->flags);
1332 		/*
1333 		 * We fatal error on write before. Try to writeback
1334 		 * every page again.
1335 		 */
1336 		if (ctx->error < 0)
1337 			invalidate_inode_pages2(inode->i_mapping);
1338 		filp->private_data = NULL;
1339 		put_nfs_open_context_sync(ctx);
1340 	}
1341 }
1342 
1343 /*
1344  * These allocate and release file read/write context information.
1345  */
nfs_open(struct inode * inode,struct file * filp)1346 int nfs_open(struct inode *inode, struct file *filp)
1347 {
1348 	struct nfs_open_context *ctx;
1349 
1350 	ctx = alloc_nfs_open_context(file_dentry(filp),
1351 				     flags_to_mode(filp->f_flags), filp);
1352 	if (IS_ERR(ctx))
1353 		return PTR_ERR(ctx);
1354 	nfs_file_set_open_context(filp, ctx);
1355 	put_nfs_open_context(ctx);
1356 	nfs_fscache_open_file(inode, filp);
1357 	return 0;
1358 }
1359 
1360 /*
1361  * This function is called whenever some part of NFS notices that
1362  * the cached attributes have to be refreshed.
1363  */
1364 int
__nfs_revalidate_inode(struct nfs_server * server,struct inode * inode)1365 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1366 {
1367 	int		 status = -ESTALE;
1368 	struct nfs_fattr *fattr = NULL;
1369 	struct nfs_inode *nfsi = NFS_I(inode);
1370 
1371 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Lu)\n",
1372 		inode->i_sb->s_id, (unsigned long long)NFS_FILEID(inode));
1373 
1374 	trace_nfs_revalidate_inode_enter(inode);
1375 
1376 	if (is_bad_inode(inode))
1377 		goto out;
1378 	if (NFS_STALE(inode))
1379 		goto out;
1380 
1381 	/* pNFS: Attributes aren't updated until we layoutcommit */
1382 	if (S_ISREG(inode->i_mode)) {
1383 		status = pnfs_sync_inode(inode, false);
1384 		if (status)
1385 			goto out;
1386 	}
1387 
1388 	status = -ENOMEM;
1389 	fattr = nfs_alloc_fattr_with_label(NFS_SERVER(inode));
1390 	if (fattr == NULL)
1391 		goto out;
1392 
1393 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
1394 
1395 	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr, inode);
1396 	if (status != 0) {
1397 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) getattr failed, error=%d\n",
1398 			 inode->i_sb->s_id,
1399 			 (unsigned long long)NFS_FILEID(inode), status);
1400 		switch (status) {
1401 		case -ETIMEDOUT:
1402 			/* A soft timeout occurred. Use cached information? */
1403 			if (server->flags & NFS_MOUNT_SOFTREVAL)
1404 				status = 0;
1405 			break;
1406 		case -ESTALE:
1407 			if (!S_ISDIR(inode->i_mode))
1408 				nfs_set_inode_stale(inode);
1409 			else
1410 				nfs_zap_caches(inode);
1411 		}
1412 		goto out;
1413 	}
1414 
1415 	status = nfs_refresh_inode(inode, fattr);
1416 	if (status) {
1417 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) refresh failed, error=%d\n",
1418 			 inode->i_sb->s_id,
1419 			 (unsigned long long)NFS_FILEID(inode), status);
1420 		goto out;
1421 	}
1422 
1423 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
1424 		nfs_zap_acl_cache(inode);
1425 
1426 	nfs_setsecurity(inode, fattr);
1427 
1428 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) revalidation complete\n",
1429 		inode->i_sb->s_id,
1430 		(unsigned long long)NFS_FILEID(inode));
1431 
1432 out:
1433 	nfs_free_fattr(fattr);
1434 	trace_nfs_revalidate_inode_exit(inode, status);
1435 	return status;
1436 }
1437 
nfs_attribute_cache_expired(struct inode * inode)1438 int nfs_attribute_cache_expired(struct inode *inode)
1439 {
1440 	if (nfs_have_delegated_attributes(inode))
1441 		return 0;
1442 	return nfs_attribute_timeout(inode);
1443 }
1444 
1445 /**
1446  * nfs_revalidate_inode - Revalidate the inode attributes
1447  * @inode: pointer to inode struct
1448  * @flags: cache flags to check
1449  *
1450  * Updates inode attribute information by retrieving the data from the server.
1451  */
nfs_revalidate_inode(struct inode * inode,unsigned long flags)1452 int nfs_revalidate_inode(struct inode *inode, unsigned long flags)
1453 {
1454 	if (!nfs_check_cache_invalid(inode, flags))
1455 		return NFS_STALE(inode) ? -ESTALE : 0;
1456 	return __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1457 }
1458 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
1459 
nfs_invalidate_mapping(struct inode * inode,struct address_space * mapping)1460 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
1461 {
1462 	int ret;
1463 
1464 	nfs_fscache_invalidate(inode, 0);
1465 	if (mapping->nrpages != 0) {
1466 		if (S_ISREG(inode->i_mode)) {
1467 			ret = nfs_sync_mapping(mapping);
1468 			if (ret < 0)
1469 				return ret;
1470 		}
1471 		ret = invalidate_inode_pages2(mapping);
1472 		if (ret < 0)
1473 			return ret;
1474 	}
1475 	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
1476 
1477 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
1478 			inode->i_sb->s_id,
1479 			(unsigned long long)NFS_FILEID(inode));
1480 	return 0;
1481 }
1482 
1483 /**
1484  * nfs_clear_invalid_mapping - Conditionally clear a mapping
1485  * @mapping: pointer to mapping
1486  *
1487  * If the NFS_INO_INVALID_DATA inode flag is set, clear the mapping.
1488  */
nfs_clear_invalid_mapping(struct address_space * mapping)1489 int nfs_clear_invalid_mapping(struct address_space *mapping)
1490 {
1491 	struct inode *inode = mapping->host;
1492 	struct nfs_inode *nfsi = NFS_I(inode);
1493 	unsigned long *bitlock = &nfsi->flags;
1494 	int ret = 0;
1495 
1496 	/*
1497 	 * We must clear NFS_INO_INVALID_DATA first to ensure that
1498 	 * invalidations that come in while we're shooting down the mappings
1499 	 * are respected. But, that leaves a race window where one revalidator
1500 	 * can clear the flag, and then another checks it before the mapping
1501 	 * gets invalidated. Fix that by serializing access to this part of
1502 	 * the function.
1503 	 *
1504 	 * At the same time, we need to allow other tasks to see whether we
1505 	 * might be in the middle of invalidating the pages, so we only set
1506 	 * the bit lock here if it looks like we're going to be doing that.
1507 	 */
1508 	for (;;) {
1509 		ret = wait_on_bit_action(bitlock, NFS_INO_INVALIDATING,
1510 					 nfs_wait_bit_killable,
1511 					 TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
1512 		if (ret)
1513 			goto out;
1514 		smp_rmb(); /* pairs with smp_wmb() below */
1515 		if (test_bit(NFS_INO_INVALIDATING, bitlock))
1516 			continue;
1517 		/* pairs with nfs_set_cache_invalid()'s smp_store_release() */
1518 		if (!(smp_load_acquire(&nfsi->cache_validity) & NFS_INO_INVALID_DATA))
1519 			goto out;
1520 		/* Slow-path that double-checks with spinlock held */
1521 		spin_lock(&inode->i_lock);
1522 		if (test_bit(NFS_INO_INVALIDATING, bitlock)) {
1523 			spin_unlock(&inode->i_lock);
1524 			continue;
1525 		}
1526 		if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1527 			break;
1528 		spin_unlock(&inode->i_lock);
1529 		goto out;
1530 	}
1531 
1532 	set_bit(NFS_INO_INVALIDATING, bitlock);
1533 	smp_wmb();
1534 	nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
1535 	nfs_ooo_clear(nfsi);
1536 	spin_unlock(&inode->i_lock);
1537 	trace_nfs_invalidate_mapping_enter(inode);
1538 	ret = nfs_invalidate_mapping(inode, mapping);
1539 	trace_nfs_invalidate_mapping_exit(inode, ret);
1540 
1541 	clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
1542 	smp_mb__after_atomic();
1543 	wake_up_bit(bitlock, NFS_INO_INVALIDATING);
1544 out:
1545 	return ret;
1546 }
1547 
nfs_mapping_need_revalidate_inode(struct inode * inode)1548 bool nfs_mapping_need_revalidate_inode(struct inode *inode)
1549 {
1550 	return nfs_check_cache_invalid(inode, NFS_INO_INVALID_CHANGE) ||
1551 		NFS_STALE(inode);
1552 }
1553 
nfs_revalidate_mapping_rcu(struct inode * inode)1554 int nfs_revalidate_mapping_rcu(struct inode *inode)
1555 {
1556 	struct nfs_inode *nfsi = NFS_I(inode);
1557 	unsigned long *bitlock = &nfsi->flags;
1558 	int ret = 0;
1559 
1560 	if (IS_SWAPFILE(inode))
1561 		goto out;
1562 	if (nfs_mapping_need_revalidate_inode(inode)) {
1563 		ret = -ECHILD;
1564 		goto out;
1565 	}
1566 	spin_lock(&inode->i_lock);
1567 	if (test_bit(NFS_INO_INVALIDATING, bitlock) ||
1568 	    (nfsi->cache_validity & NFS_INO_INVALID_DATA))
1569 		ret = -ECHILD;
1570 	spin_unlock(&inode->i_lock);
1571 out:
1572 	return ret;
1573 }
1574 
1575 /**
1576  * nfs_revalidate_mapping - Revalidate the pagecache
1577  * @inode: pointer to host inode
1578  * @mapping: pointer to mapping
1579  */
nfs_revalidate_mapping(struct inode * inode,struct address_space * mapping)1580 int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
1581 {
1582 	/* swapfiles are not supposed to be shared. */
1583 	if (IS_SWAPFILE(inode))
1584 		return 0;
1585 
1586 	if (nfs_mapping_need_revalidate_inode(inode)) {
1587 		int ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1588 		if (ret < 0)
1589 			return ret;
1590 	}
1591 
1592 	return nfs_clear_invalid_mapping(mapping);
1593 }
1594 
nfs_file_has_writers(struct nfs_inode * nfsi)1595 static bool nfs_file_has_writers(struct nfs_inode *nfsi)
1596 {
1597 	struct inode *inode = &nfsi->vfs_inode;
1598 
1599 	if (!S_ISREG(inode->i_mode))
1600 		return false;
1601 	if (list_empty(&nfsi->open_files))
1602 		return false;
1603 	return inode_is_open_for_write(inode);
1604 }
1605 
nfs_file_has_buffered_writers(struct nfs_inode * nfsi)1606 static bool nfs_file_has_buffered_writers(struct nfs_inode *nfsi)
1607 {
1608 	return nfs_file_has_writers(nfsi) && nfs_file_io_is_buffered(nfsi);
1609 }
1610 
nfs_wcc_update_inode(struct inode * inode,struct nfs_fattr * fattr)1611 static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1612 {
1613 	struct timespec64 ts;
1614 
1615 	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
1616 			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
1617 			&& inode_eq_iversion_raw(inode, fattr->pre_change_attr)) {
1618 		inode_set_iversion_raw(inode, fattr->change_attr);
1619 		if (S_ISDIR(inode->i_mode))
1620 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1621 		else if (nfs_server_capable(inode, NFS_CAP_XATTR))
1622 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_XATTR);
1623 	}
1624 	/* If we have atomic WCC data, we may update some attributes */
1625 	ts = inode_get_ctime(inode);
1626 	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
1627 			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
1628 			&& timespec64_equal(&ts, &fattr->pre_ctime)) {
1629 		inode_set_ctime_to_ts(inode, fattr->ctime);
1630 	}
1631 
1632 	ts = inode_get_mtime(inode);
1633 	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
1634 			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
1635 			&& timespec64_equal(&ts, &fattr->pre_mtime)) {
1636 		inode_set_mtime_to_ts(inode, fattr->mtime);
1637 	}
1638 	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
1639 			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
1640 			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
1641 			&& !nfs_have_writebacks(inode)) {
1642 		trace_nfs_size_wcc(inode, fattr->size);
1643 		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
1644 	}
1645 }
1646 
1647 /**
1648  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1649  * @inode: pointer to inode
1650  * @fattr: updated attributes
1651  *
1652  * Verifies the attribute cache. If we have just changed the attributes,
1653  * so that fattr carries weak cache consistency data, then it may
1654  * also update the ctime/mtime/change_attribute.
1655  */
nfs_check_inode_attributes(struct inode * inode,struct nfs_fattr * fattr)1656 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1657 {
1658 	struct nfs_inode *nfsi = NFS_I(inode);
1659 	loff_t cur_size, new_isize;
1660 	unsigned long invalid = 0;
1661 	struct timespec64 ts;
1662 
1663 	if (nfs_have_delegated_attributes(inode))
1664 		return 0;
1665 
1666 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
1667 		/* Only a mounted-on-fileid? Just exit */
1668 		if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
1669 			return 0;
1670 	/* Has the inode gone and changed behind our back? */
1671 	} else if (nfsi->fileid != fattr->fileid) {
1672 		/* Is this perhaps the mounted-on fileid? */
1673 		if ((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) &&
1674 		    nfsi->fileid == fattr->mounted_on_fileid)
1675 			return 0;
1676 		return -ESTALE;
1677 	}
1678 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && inode_wrong_type(inode, fattr->mode))
1679 		return -ESTALE;
1680 
1681 
1682 	if (!nfs_file_has_buffered_writers(nfsi)) {
1683 		/* Verify a few of the more important attributes */
1684 		if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 && !inode_eq_iversion_raw(inode, fattr->change_attr))
1685 			invalid |= NFS_INO_INVALID_CHANGE;
1686 
1687 		ts = inode_get_mtime(inode);
1688 		if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec64_equal(&ts, &fattr->mtime))
1689 			invalid |= NFS_INO_INVALID_MTIME;
1690 
1691 		ts = inode_get_ctime(inode);
1692 		if ((fattr->valid & NFS_ATTR_FATTR_CTIME) && !timespec64_equal(&ts, &fattr->ctime))
1693 			invalid |= NFS_INO_INVALID_CTIME;
1694 
1695 		if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1696 			cur_size = i_size_read(inode);
1697 			new_isize = nfs_size_to_loff_t(fattr->size);
1698 			if (cur_size != new_isize)
1699 				invalid |= NFS_INO_INVALID_SIZE;
1700 		}
1701 	}
1702 
1703 	/* Have any file permissions changed? */
1704 	if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
1705 		invalid |= NFS_INO_INVALID_MODE;
1706 	if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && !uid_eq(inode->i_uid, fattr->uid))
1707 		invalid |= NFS_INO_INVALID_OTHER;
1708 	if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && !gid_eq(inode->i_gid, fattr->gid))
1709 		invalid |= NFS_INO_INVALID_OTHER;
1710 
1711 	/* Has the link count changed? */
1712 	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
1713 		invalid |= NFS_INO_INVALID_NLINK;
1714 
1715 	ts = inode_get_atime(inode);
1716 	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec64_equal(&ts, &fattr->atime))
1717 		invalid |= NFS_INO_INVALID_ATIME;
1718 
1719 	if (invalid != 0)
1720 		nfs_set_cache_invalid(inode, invalid);
1721 
1722 	nfsi->read_cache_jiffies = fattr->time_start;
1723 	return 0;
1724 }
1725 
1726 static atomic_long_t nfs_attr_generation_counter;
1727 
nfs_read_attr_generation_counter(void)1728 static unsigned long nfs_read_attr_generation_counter(void)
1729 {
1730 	return atomic_long_read(&nfs_attr_generation_counter);
1731 }
1732 
nfs_inc_attr_generation_counter(void)1733 unsigned long nfs_inc_attr_generation_counter(void)
1734 {
1735 	return atomic_long_inc_return(&nfs_attr_generation_counter);
1736 }
1737 EXPORT_SYMBOL_GPL(nfs_inc_attr_generation_counter);
1738 
nfs_fattr_init(struct nfs_fattr * fattr)1739 void nfs_fattr_init(struct nfs_fattr *fattr)
1740 {
1741 	fattr->valid = 0;
1742 	fattr->time_start = jiffies;
1743 	fattr->gencount = nfs_inc_attr_generation_counter();
1744 	fattr->owner_name = NULL;
1745 	fattr->group_name = NULL;
1746 	fattr->mdsthreshold = NULL;
1747 }
1748 EXPORT_SYMBOL_GPL(nfs_fattr_init);
1749 
1750 /**
1751  * nfs_fattr_set_barrier
1752  * @fattr: attributes
1753  *
1754  * Used to set a barrier after an attribute was updated. This
1755  * barrier ensures that older attributes from RPC calls that may
1756  * have raced with our update cannot clobber these new values.
1757  * Note that you are still responsible for ensuring that other
1758  * operations which change the attribute on the server do not
1759  * collide.
1760  */
nfs_fattr_set_barrier(struct nfs_fattr * fattr)1761 void nfs_fattr_set_barrier(struct nfs_fattr *fattr)
1762 {
1763 	fattr->gencount = nfs_inc_attr_generation_counter();
1764 }
1765 
nfs_alloc_fattr(void)1766 struct nfs_fattr *nfs_alloc_fattr(void)
1767 {
1768 	struct nfs_fattr *fattr;
1769 
1770 	fattr = kmalloc(sizeof(*fattr), GFP_KERNEL);
1771 	if (fattr != NULL) {
1772 		nfs_fattr_init(fattr);
1773 		fattr->label = NULL;
1774 	}
1775 	return fattr;
1776 }
1777 EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
1778 
nfs_alloc_fattr_with_label(struct nfs_server * server)1779 struct nfs_fattr *nfs_alloc_fattr_with_label(struct nfs_server *server)
1780 {
1781 	struct nfs_fattr *fattr = nfs_alloc_fattr();
1782 
1783 	if (!fattr)
1784 		return NULL;
1785 
1786 	fattr->label = nfs4_label_alloc(server, GFP_KERNEL);
1787 	if (IS_ERR(fattr->label)) {
1788 		kfree(fattr);
1789 		return NULL;
1790 	}
1791 
1792 	return fattr;
1793 }
1794 EXPORT_SYMBOL_GPL(nfs_alloc_fattr_with_label);
1795 
nfs_alloc_fhandle(void)1796 struct nfs_fh *nfs_alloc_fhandle(void)
1797 {
1798 	struct nfs_fh *fh;
1799 
1800 	fh = kmalloc(sizeof(struct nfs_fh), GFP_KERNEL);
1801 	if (fh != NULL)
1802 		fh->size = 0;
1803 	return fh;
1804 }
1805 EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
1806 
1807 #ifdef NFS_DEBUG
1808 /*
1809  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1810  *                             in the same way that wireshark does
1811  *
1812  * @fh: file handle
1813  *
1814  * For debugging only.
1815  */
_nfs_display_fhandle_hash(const struct nfs_fh * fh)1816 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1817 {
1818 	/* wireshark uses 32-bit AUTODIN crc and does a bitwise
1819 	 * not on the result */
1820 	return nfs_fhandle_hash(fh);
1821 }
1822 EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
1823 
1824 /*
1825  * _nfs_display_fhandle - display an NFS file handle on the console
1826  *
1827  * @fh: file handle to display
1828  * @caption: display caption
1829  *
1830  * For debugging only.
1831  */
_nfs_display_fhandle(const struct nfs_fh * fh,const char * caption)1832 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1833 {
1834 	unsigned short i;
1835 
1836 	if (fh == NULL || fh->size == 0) {
1837 		printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1838 		return;
1839 	}
1840 
1841 	printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1842 	       caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1843 	for (i = 0; i < fh->size; i += 16) {
1844 		__be32 *pos = (__be32 *)&fh->data[i];
1845 
1846 		switch ((fh->size - i - 1) >> 2) {
1847 		case 0:
1848 			printk(KERN_DEFAULT " %08x\n",
1849 				be32_to_cpup(pos));
1850 			break;
1851 		case 1:
1852 			printk(KERN_DEFAULT " %08x %08x\n",
1853 				be32_to_cpup(pos), be32_to_cpup(pos + 1));
1854 			break;
1855 		case 2:
1856 			printk(KERN_DEFAULT " %08x %08x %08x\n",
1857 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1858 				be32_to_cpup(pos + 2));
1859 			break;
1860 		default:
1861 			printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1862 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1863 				be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1864 		}
1865 	}
1866 }
1867 EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
1868 #endif
1869 
1870 /**
1871  * nfs_inode_attrs_cmp_generic - compare attributes
1872  * @fattr: attributes
1873  * @inode: pointer to inode
1874  *
1875  * Attempt to divine whether or not an RPC call reply carrying stale
1876  * attributes got scheduled after another call carrying updated ones.
1877  * Note also the check for wraparound of 'attr_gencount'
1878  *
1879  * The function returns '1' if it thinks the attributes in @fattr are
1880  * more recent than the ones cached in @inode. Otherwise it returns
1881  * the value '0'.
1882  */
nfs_inode_attrs_cmp_generic(const struct nfs_fattr * fattr,const struct inode * inode)1883 static int nfs_inode_attrs_cmp_generic(const struct nfs_fattr *fattr,
1884 				       const struct inode *inode)
1885 {
1886 	unsigned long attr_gencount = NFS_I(inode)->attr_gencount;
1887 
1888 	return (long)(fattr->gencount - attr_gencount) > 0 ||
1889 	       (long)(attr_gencount - nfs_read_attr_generation_counter()) > 0;
1890 }
1891 
1892 /**
1893  * nfs_inode_attrs_cmp_monotonic - compare attributes
1894  * @fattr: attributes
1895  * @inode: pointer to inode
1896  *
1897  * Attempt to divine whether or not an RPC call reply carrying stale
1898  * attributes got scheduled after another call carrying updated ones.
1899  *
1900  * We assume that the server observes monotonic semantics for
1901  * the change attribute, so a larger value means that the attributes in
1902  * @fattr are more recent, in which case the function returns the
1903  * value '1'.
1904  * A return value of '0' indicates no measurable change
1905  * A return value of '-1' means that the attributes in @inode are
1906  * more recent.
1907  */
nfs_inode_attrs_cmp_monotonic(const struct nfs_fattr * fattr,const struct inode * inode)1908 static int nfs_inode_attrs_cmp_monotonic(const struct nfs_fattr *fattr,
1909 					 const struct inode *inode)
1910 {
1911 	s64 diff = fattr->change_attr - inode_peek_iversion_raw(inode);
1912 	if (diff > 0)
1913 		return 1;
1914 	return diff == 0 ? 0 : -1;
1915 }
1916 
1917 /**
1918  * nfs_inode_attrs_cmp_strict_monotonic - compare attributes
1919  * @fattr: attributes
1920  * @inode: pointer to inode
1921  *
1922  * Attempt to divine whether or not an RPC call reply carrying stale
1923  * attributes got scheduled after another call carrying updated ones.
1924  *
1925  * We assume that the server observes strictly monotonic semantics for
1926  * the change attribute, so a larger value means that the attributes in
1927  * @fattr are more recent, in which case the function returns the
1928  * value '1'.
1929  * A return value of '-1' means that the attributes in @inode are
1930  * more recent or unchanged.
1931  */
nfs_inode_attrs_cmp_strict_monotonic(const struct nfs_fattr * fattr,const struct inode * inode)1932 static int nfs_inode_attrs_cmp_strict_monotonic(const struct nfs_fattr *fattr,
1933 						const struct inode *inode)
1934 {
1935 	return  nfs_inode_attrs_cmp_monotonic(fattr, inode) > 0 ? 1 : -1;
1936 }
1937 
1938 /**
1939  * nfs_inode_attrs_cmp - compare attributes
1940  * @fattr: attributes
1941  * @inode: pointer to inode
1942  *
1943  * This function returns '1' if it thinks the attributes in @fattr are
1944  * more recent than the ones cached in @inode. It returns '-1' if
1945  * the attributes in @inode are more recent than the ones in @fattr,
1946  * and it returns 0 if not sure.
1947  */
nfs_inode_attrs_cmp(const struct nfs_fattr * fattr,const struct inode * inode)1948 static int nfs_inode_attrs_cmp(const struct nfs_fattr *fattr,
1949 			       const struct inode *inode)
1950 {
1951 	if (nfs_inode_attrs_cmp_generic(fattr, inode) > 0)
1952 		return 1;
1953 	switch (NFS_SERVER(inode)->change_attr_type) {
1954 	case NFS4_CHANGE_TYPE_IS_UNDEFINED:
1955 		break;
1956 	case NFS4_CHANGE_TYPE_IS_TIME_METADATA:
1957 		if (!(fattr->valid & NFS_ATTR_FATTR_CHANGE))
1958 			break;
1959 		return nfs_inode_attrs_cmp_monotonic(fattr, inode);
1960 	default:
1961 		if (!(fattr->valid & NFS_ATTR_FATTR_CHANGE))
1962 			break;
1963 		return nfs_inode_attrs_cmp_strict_monotonic(fattr, inode);
1964 	}
1965 	return 0;
1966 }
1967 
1968 /**
1969  * nfs_inode_finish_partial_attr_update - complete a previous inode update
1970  * @fattr: attributes
1971  * @inode: pointer to inode
1972  *
1973  * Returns '1' if the last attribute update left the inode cached
1974  * attributes in a partially unrevalidated state, and @fattr
1975  * matches the change attribute of that partial update.
1976  * Otherwise returns '0'.
1977  */
nfs_inode_finish_partial_attr_update(const struct nfs_fattr * fattr,const struct inode * inode)1978 static int nfs_inode_finish_partial_attr_update(const struct nfs_fattr *fattr,
1979 						const struct inode *inode)
1980 {
1981 	const unsigned long check_valid =
1982 		NFS_INO_INVALID_ATIME | NFS_INO_INVALID_CTIME |
1983 		NFS_INO_INVALID_MTIME | NFS_INO_INVALID_SIZE |
1984 		NFS_INO_INVALID_BLOCKS | NFS_INO_INVALID_OTHER |
1985 		NFS_INO_INVALID_NLINK | NFS_INO_INVALID_BTIME;
1986 	unsigned long cache_validity = NFS_I(inode)->cache_validity;
1987 	enum nfs4_change_attr_type ctype = NFS_SERVER(inode)->change_attr_type;
1988 
1989 	if (ctype != NFS4_CHANGE_TYPE_IS_UNDEFINED &&
1990 	    !(cache_validity & NFS_INO_INVALID_CHANGE) &&
1991 	    (cache_validity & check_valid) != 0 &&
1992 	    (fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1993 	    nfs_inode_attrs_cmp_monotonic(fattr, inode) == 0)
1994 		return 1;
1995 	return 0;
1996 }
1997 
nfs_ooo_merge(struct nfs_inode * nfsi,u64 start,u64 end)1998 static void nfs_ooo_merge(struct nfs_inode *nfsi,
1999 			  u64 start, u64 end)
2000 {
2001 	int i, cnt;
2002 
2003 	if (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER)
2004 		/* No point merging anything */
2005 		return;
2006 
2007 	if (!nfsi->ooo) {
2008 		nfsi->ooo = kmalloc(sizeof(*nfsi->ooo), GFP_ATOMIC);
2009 		if (!nfsi->ooo) {
2010 			nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
2011 			return;
2012 		}
2013 		nfsi->ooo->cnt = 0;
2014 	}
2015 
2016 	/* add this range, merging if possible */
2017 	cnt = nfsi->ooo->cnt;
2018 	for (i = 0; i < cnt; i++) {
2019 		if (end == nfsi->ooo->gap[i].start)
2020 			end = nfsi->ooo->gap[i].end;
2021 		else if (start == nfsi->ooo->gap[i].end)
2022 			start = nfsi->ooo->gap[i].start;
2023 		else
2024 			continue;
2025 		/* Remove 'i' from table and loop to insert the new range */
2026 		cnt -= 1;
2027 		nfsi->ooo->gap[i] = nfsi->ooo->gap[cnt];
2028 		i = -1;
2029 	}
2030 	if (start != end) {
2031 		if (cnt >= ARRAY_SIZE(nfsi->ooo->gap)) {
2032 			nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
2033 			kfree(nfsi->ooo);
2034 			nfsi->ooo = NULL;
2035 			return;
2036 		}
2037 		nfsi->ooo->gap[cnt].start = start;
2038 		nfsi->ooo->gap[cnt].end = end;
2039 		cnt += 1;
2040 	}
2041 	nfsi->ooo->cnt = cnt;
2042 }
2043 
nfs_ooo_record(struct nfs_inode * nfsi,struct nfs_fattr * fattr)2044 static void nfs_ooo_record(struct nfs_inode *nfsi,
2045 			   struct nfs_fattr *fattr)
2046 {
2047 	/* This reply was out-of-order, so record in the
2048 	 * pre/post change id, possibly cancelling
2049 	 * gaps created when iversion was jumpped forward.
2050 	 */
2051 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) &&
2052 	    (fattr->valid & NFS_ATTR_FATTR_PRECHANGE))
2053 		nfs_ooo_merge(nfsi,
2054 			      fattr->change_attr,
2055 			      fattr->pre_change_attr);
2056 }
2057 
nfs_refresh_inode_locked(struct inode * inode,struct nfs_fattr * fattr)2058 static int nfs_refresh_inode_locked(struct inode *inode,
2059 				    struct nfs_fattr *fattr)
2060 {
2061 	int attr_cmp = nfs_inode_attrs_cmp(fattr, inode);
2062 	int ret = 0;
2063 
2064 	trace_nfs_refresh_inode_enter(inode);
2065 
2066 	if (attr_cmp > 0 || nfs_inode_finish_partial_attr_update(fattr, inode))
2067 		ret = nfs_update_inode(inode, fattr);
2068 	else {
2069 		nfs_ooo_record(NFS_I(inode), fattr);
2070 
2071 		if (attr_cmp == 0)
2072 			ret = nfs_check_inode_attributes(inode, fattr);
2073 	}
2074 
2075 	trace_nfs_refresh_inode_exit(inode, ret);
2076 	return ret;
2077 }
2078 
2079 /**
2080  * nfs_refresh_inode - try to update the inode attribute cache
2081  * @inode: pointer to inode
2082  * @fattr: updated attributes
2083  *
2084  * Check that an RPC call that returned attributes has not overlapped with
2085  * other recent updates of the inode metadata, then decide whether it is
2086  * safe to do a full update of the inode attributes, or whether just to
2087  * call nfs_check_inode_attributes.
2088  */
nfs_refresh_inode(struct inode * inode,struct nfs_fattr * fattr)2089 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
2090 {
2091 	int status;
2092 
2093 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
2094 		return 0;
2095 	spin_lock(&inode->i_lock);
2096 	status = nfs_refresh_inode_locked(inode, fattr);
2097 	spin_unlock(&inode->i_lock);
2098 
2099 	return status;
2100 }
2101 EXPORT_SYMBOL_GPL(nfs_refresh_inode);
2102 
nfs_post_op_update_inode_locked(struct inode * inode,struct nfs_fattr * fattr,unsigned int invalid)2103 static int nfs_post_op_update_inode_locked(struct inode *inode,
2104 		struct nfs_fattr *fattr, unsigned int invalid)
2105 {
2106 	if (S_ISDIR(inode->i_mode))
2107 		invalid |= NFS_INO_INVALID_DATA;
2108 	nfs_set_cache_invalid(inode, invalid);
2109 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
2110 		return 0;
2111 	return nfs_refresh_inode_locked(inode, fattr);
2112 }
2113 
2114 /**
2115  * nfs_post_op_update_inode - try to update the inode attribute cache
2116  * @inode: pointer to inode
2117  * @fattr: updated attributes
2118  *
2119  * After an operation that has changed the inode metadata, mark the
2120  * attribute cache as being invalid, then try to update it.
2121  *
2122  * NB: if the server didn't return any post op attributes, this
2123  * function will force the retrieval of attributes before the next
2124  * NFS request.  Thus it should be used only for operations that
2125  * are expected to change one or more attributes, to avoid
2126  * unnecessary NFS requests and trips through nfs_update_inode().
2127  */
nfs_post_op_update_inode(struct inode * inode,struct nfs_fattr * fattr)2128 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
2129 {
2130 	int status;
2131 
2132 	spin_lock(&inode->i_lock);
2133 	nfs_fattr_set_barrier(fattr);
2134 	status = nfs_post_op_update_inode_locked(inode, fattr,
2135 			NFS_INO_INVALID_CHANGE
2136 			| NFS_INO_INVALID_CTIME
2137 			| NFS_INO_REVAL_FORCED);
2138 	spin_unlock(&inode->i_lock);
2139 
2140 	return status;
2141 }
2142 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
2143 
2144 /**
2145  * nfs_post_op_update_inode_force_wcc_locked - update the inode attribute cache
2146  * @inode: pointer to inode
2147  * @fattr: updated attributes
2148  *
2149  * After an operation that has changed the inode metadata, mark the
2150  * attribute cache as being invalid, then try to update it. Fake up
2151  * weak cache consistency data, if none exist.
2152  *
2153  * This function is mainly designed to be used by the ->write_done() functions.
2154  */
nfs_post_op_update_inode_force_wcc_locked(struct inode * inode,struct nfs_fattr * fattr)2155 int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr)
2156 {
2157 	int attr_cmp = nfs_inode_attrs_cmp(fattr, inode);
2158 	int status;
2159 
2160 	/* Don't do a WCC update if these attributes are already stale */
2161 	if (attr_cmp < 0)
2162 		return 0;
2163 	if ((fattr->valid & NFS_ATTR_FATTR) == 0 || !attr_cmp) {
2164 		/* Record the pre/post change info before clearing PRECHANGE */
2165 		nfs_ooo_record(NFS_I(inode), fattr);
2166 		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
2167 				| NFS_ATTR_FATTR_PRESIZE
2168 				| NFS_ATTR_FATTR_PREMTIME
2169 				| NFS_ATTR_FATTR_PRECTIME);
2170 		goto out_noforce;
2171 	}
2172 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
2173 			(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
2174 		fattr->pre_change_attr = inode_peek_iversion_raw(inode);
2175 		fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
2176 	}
2177 	if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
2178 			(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
2179 		fattr->pre_ctime = inode_get_ctime(inode);
2180 		fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
2181 	}
2182 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
2183 			(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
2184 		fattr->pre_mtime = inode_get_mtime(inode);
2185 		fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
2186 	}
2187 	if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
2188 			(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
2189 		fattr->pre_size = i_size_read(inode);
2190 		fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
2191 	}
2192 out_noforce:
2193 	status = nfs_post_op_update_inode_locked(inode, fattr,
2194 			NFS_INO_INVALID_CHANGE
2195 			| NFS_INO_INVALID_CTIME
2196 			| NFS_INO_INVALID_MTIME
2197 			| NFS_INO_INVALID_BLOCKS);
2198 	return status;
2199 }
2200 
2201 /**
2202  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
2203  * @inode: pointer to inode
2204  * @fattr: updated attributes
2205  *
2206  * After an operation that has changed the inode metadata, mark the
2207  * attribute cache as being invalid, then try to update it. Fake up
2208  * weak cache consistency data, if none exist.
2209  *
2210  * This function is mainly designed to be used by the ->write_done() functions.
2211  */
nfs_post_op_update_inode_force_wcc(struct inode * inode,struct nfs_fattr * fattr)2212 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
2213 {
2214 	int status;
2215 
2216 	spin_lock(&inode->i_lock);
2217 	nfs_fattr_set_barrier(fattr);
2218 	status = nfs_post_op_update_inode_force_wcc_locked(inode, fattr);
2219 	spin_unlock(&inode->i_lock);
2220 	return status;
2221 }
2222 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
2223 
2224 
2225 /*
2226  * Many nfs protocol calls return the new file attributes after
2227  * an operation.  Here we update the inode to reflect the state
2228  * of the server's inode.
2229  *
2230  * This is a bit tricky because we have to make sure all dirty pages
2231  * have been sent off to the server before calling invalidate_inode_pages.
2232  * To make sure no other process adds more write requests while we try
2233  * our best to flush them, we make them sleep during the attribute refresh.
2234  *
2235  * A very similar scenario holds for the dir cache.
2236  */
nfs_update_inode(struct inode * inode,struct nfs_fattr * fattr)2237 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
2238 {
2239 	struct nfs_server *server = NFS_SERVER(inode);
2240 	struct nfs_inode *nfsi = NFS_I(inode);
2241 	loff_t cur_isize, new_isize;
2242 	u64 fattr_supported = server->fattr_valid;
2243 	unsigned long invalid = 0;
2244 	unsigned long now = jiffies;
2245 	unsigned long save_cache_validity;
2246 	bool have_writers = nfs_file_has_buffered_writers(nfsi);
2247 	bool cache_revalidated = true;
2248 	bool attr_changed = false;
2249 	bool have_delegation;
2250 
2251 	dfprintk(VFS, "NFS: %s(%s/%lu fh_crc=0x%08x ct=%d info=0x%llx)\n",
2252 			__func__, inode->i_sb->s_id, inode->i_ino,
2253 			nfs_display_fhandle_hash(NFS_FH(inode)),
2254 			icount_read(inode), fattr->valid);
2255 
2256 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
2257 		/* Only a mounted-on-fileid? Just exit */
2258 		if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
2259 			return 0;
2260 	/* Has the inode gone and changed behind our back? */
2261 	} else if (nfsi->fileid != fattr->fileid) {
2262 		/* Is this perhaps the mounted-on fileid? */
2263 		if ((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) &&
2264 		    nfsi->fileid == fattr->mounted_on_fileid)
2265 			return 0;
2266 		printk(KERN_ERR "NFS: server %s error: fileid changed\n"
2267 			"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
2268 			NFS_SERVER(inode)->nfs_client->cl_hostname,
2269 			inode->i_sb->s_id, (long long)nfsi->fileid,
2270 			(long long)fattr->fileid);
2271 		goto out_err;
2272 	}
2273 
2274 	/*
2275 	 * Make sure the inode's type hasn't changed.
2276 	 */
2277 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && inode_wrong_type(inode, fattr->mode)) {
2278 		/*
2279 		* Big trouble! The inode has become a different object.
2280 		*/
2281 		printk(KERN_DEBUG "NFS: %s: inode %lu mode changed, %07o to %07o\n",
2282 				__func__, inode->i_ino, inode->i_mode, fattr->mode);
2283 		goto out_err;
2284 	}
2285 
2286 	/* Update the fsid? */
2287 	if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
2288 			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
2289 			!IS_AUTOMOUNT(inode))
2290 		server->fsid = fattr->fsid;
2291 
2292 	/* Save the delegation state before clearing cache_validity */
2293 	have_delegation = nfs_have_delegated_attributes(inode);
2294 
2295 	/*
2296 	 * Update the read time so we don't revalidate too often.
2297 	 */
2298 	nfsi->read_cache_jiffies = fattr->time_start;
2299 
2300 	/* Fix up any delegated attributes in the struct nfs_fattr */
2301 	nfs_fattr_fixup_delegated(inode, fattr);
2302 
2303 	save_cache_validity = nfsi->cache_validity;
2304 	nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
2305 			| NFS_INO_INVALID_ATIME
2306 			| NFS_INO_REVAL_FORCED
2307 			| NFS_INO_INVALID_BLOCKS);
2308 
2309 	/* Do atomic weak cache consistency updates */
2310 	nfs_wcc_update_inode(inode, fattr);
2311 
2312 	if (pnfs_layoutcommit_outstanding(inode)) {
2313 		nfsi->cache_validity |=
2314 			save_cache_validity &
2315 			(NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_CTIME |
2316 			 NFS_INO_INVALID_MTIME | NFS_INO_INVALID_SIZE |
2317 			 NFS_INO_INVALID_BLOCKS);
2318 		cache_revalidated = false;
2319 	}
2320 
2321 	/* More cache consistency checks */
2322 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
2323 		if (!have_writers && nfsi->ooo && nfsi->ooo->cnt == 1 &&
2324 		    nfsi->ooo->gap[0].end == inode_peek_iversion_raw(inode)) {
2325 			/* There is one remaining gap that hasn't been
2326 			 * merged into iversion - do that now.
2327 			 */
2328 			inode_set_iversion_raw(inode, nfsi->ooo->gap[0].start);
2329 			kfree(nfsi->ooo);
2330 			nfsi->ooo = NULL;
2331 		}
2332 		if (!inode_eq_iversion_raw(inode, fattr->change_attr)) {
2333 			/* Could it be a race with writeback? */
2334 			if (!(have_writers || have_delegation)) {
2335 				invalid |= NFS_INO_INVALID_DATA
2336 					| NFS_INO_INVALID_ACCESS
2337 					| NFS_INO_INVALID_ACL
2338 					| NFS_INO_INVALID_XATTR;
2339 				/* Force revalidate of all attributes */
2340 				save_cache_validity |= NFS_INO_INVALID_CTIME
2341 					| NFS_INO_INVALID_MTIME
2342 					| NFS_INO_INVALID_SIZE
2343 					| NFS_INO_INVALID_BLOCKS
2344 					| NFS_INO_INVALID_NLINK
2345 					| NFS_INO_INVALID_MODE
2346 					| NFS_INO_INVALID_OTHER
2347 					| NFS_INO_INVALID_BTIME;
2348 				if (S_ISDIR(inode->i_mode))
2349 					nfs_force_lookup_revalidate(inode);
2350 				attr_changed = true;
2351 				dprintk("NFS: change_attr change on server for file %s/%ld\n",
2352 						inode->i_sb->s_id,
2353 						inode->i_ino);
2354 			} else if (!have_delegation) {
2355 				nfs_ooo_record(nfsi, fattr);
2356 				nfs_ooo_merge(nfsi, inode_peek_iversion_raw(inode),
2357 					      fattr->change_attr);
2358 			}
2359 			inode_set_iversion_raw(inode, fattr->change_attr);
2360 		}
2361 	} else {
2362 		nfsi->cache_validity |=
2363 			save_cache_validity & NFS_INO_INVALID_CHANGE;
2364 		if (!have_delegation ||
2365 		    (nfsi->cache_validity & NFS_INO_INVALID_CHANGE) != 0)
2366 			cache_revalidated = false;
2367 	}
2368 
2369 	if (fattr->valid & NFS_ATTR_FATTR_MTIME)
2370 		inode_set_mtime_to_ts(inode, fattr->mtime);
2371 	else if (fattr_supported & NFS_ATTR_FATTR_MTIME)
2372 		nfsi->cache_validity |=
2373 			save_cache_validity & NFS_INO_INVALID_MTIME;
2374 
2375 	if (fattr->valid & NFS_ATTR_FATTR_CTIME)
2376 		inode_set_ctime_to_ts(inode, fattr->ctime);
2377 	else if (fattr_supported & NFS_ATTR_FATTR_CTIME)
2378 		nfsi->cache_validity |=
2379 			save_cache_validity & NFS_INO_INVALID_CTIME;
2380 
2381 	if (fattr->valid & NFS_ATTR_FATTR_BTIME)
2382 		nfsi->btime = fattr->btime;
2383 	else if (fattr_supported & NFS_ATTR_FATTR_BTIME)
2384 		nfsi->cache_validity |=
2385 			save_cache_validity & NFS_INO_INVALID_BTIME;
2386 
2387 	/* Check if our cached file size is stale */
2388 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
2389 		new_isize = nfs_size_to_loff_t(fattr->size);
2390 		cur_isize = i_size_read(inode);
2391 		if (new_isize != cur_isize && !have_delegation) {
2392 			/* Do we perhaps have any outstanding writes, or has
2393 			 * the file grown beyond our last write? */
2394 			if (!nfs_have_writebacks(inode) || new_isize > cur_isize) {
2395 				trace_nfs_size_update(inode, new_isize);
2396 				i_size_write(inode, new_isize);
2397 				if (!have_writers)
2398 					invalid |= NFS_INO_INVALID_DATA;
2399 			}
2400 		}
2401 		if (new_isize == 0 &&
2402 		    !(fattr->valid & (NFS_ATTR_FATTR_SPACE_USED |
2403 				      NFS_ATTR_FATTR_BLOCKS_USED))) {
2404 			fattr->du.nfs3.used = 0;
2405 			fattr->valid |= NFS_ATTR_FATTR_SPACE_USED;
2406 		}
2407 	} else
2408 		nfsi->cache_validity |=
2409 			save_cache_validity & NFS_INO_INVALID_SIZE;
2410 
2411 	if (fattr->valid & NFS_ATTR_FATTR_ATIME)
2412 		inode_set_atime_to_ts(inode, fattr->atime);
2413 	else if (fattr_supported & NFS_ATTR_FATTR_ATIME)
2414 		nfsi->cache_validity |=
2415 			save_cache_validity & NFS_INO_INVALID_ATIME;
2416 
2417 	if (fattr->valid & NFS_ATTR_FATTR_MODE) {
2418 		if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
2419 			umode_t newmode = inode->i_mode & S_IFMT;
2420 			newmode |= fattr->mode & S_IALLUGO;
2421 			inode->i_mode = newmode;
2422 			invalid |= NFS_INO_INVALID_ACCESS
2423 				| NFS_INO_INVALID_ACL;
2424 		}
2425 	} else if (fattr_supported & NFS_ATTR_FATTR_MODE)
2426 		nfsi->cache_validity |=
2427 			save_cache_validity & NFS_INO_INVALID_MODE;
2428 
2429 	if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
2430 		if (!uid_eq(inode->i_uid, fattr->uid)) {
2431 			invalid |= NFS_INO_INVALID_ACCESS
2432 				| NFS_INO_INVALID_ACL;
2433 			inode->i_uid = fattr->uid;
2434 		}
2435 	} else if (fattr_supported & NFS_ATTR_FATTR_OWNER)
2436 		nfsi->cache_validity |=
2437 			save_cache_validity & NFS_INO_INVALID_OTHER;
2438 
2439 	if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
2440 		if (!gid_eq(inode->i_gid, fattr->gid)) {
2441 			invalid |= NFS_INO_INVALID_ACCESS
2442 				| NFS_INO_INVALID_ACL;
2443 			inode->i_gid = fattr->gid;
2444 		}
2445 	} else if (fattr_supported & NFS_ATTR_FATTR_GROUP)
2446 		nfsi->cache_validity |=
2447 			save_cache_validity & NFS_INO_INVALID_OTHER;
2448 
2449 	if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
2450 		if (inode->i_nlink != fattr->nlink)
2451 			set_nlink(inode, fattr->nlink);
2452 	} else if (fattr_supported & NFS_ATTR_FATTR_NLINK)
2453 		nfsi->cache_validity |=
2454 			save_cache_validity & NFS_INO_INVALID_NLINK;
2455 
2456 	if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
2457 		/*
2458 		 * report the blocks in 512byte units
2459 		 */
2460 		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
2461 	} else if (fattr_supported & NFS_ATTR_FATTR_SPACE_USED)
2462 		nfsi->cache_validity |=
2463 			save_cache_validity & NFS_INO_INVALID_BLOCKS;
2464 
2465 	if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
2466 		inode->i_blocks = fattr->du.nfs2.blocks;
2467 	else if (fattr_supported & NFS_ATTR_FATTR_BLOCKS_USED)
2468 		nfsi->cache_validity |=
2469 			save_cache_validity & NFS_INO_INVALID_BLOCKS;
2470 
2471 	/* Update attrtimeo value if we're out of the unstable period */
2472 	if (attr_changed) {
2473 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
2474 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
2475 		nfsi->attrtimeo_timestamp = now;
2476 		/* Set barrier to be more recent than all outstanding updates */
2477 		nfsi->attr_gencount = nfs_inc_attr_generation_counter();
2478 	} else {
2479 		if (cache_revalidated) {
2480 			if (!time_in_range_open(now, nfsi->attrtimeo_timestamp,
2481 				nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
2482 				nfsi->attrtimeo <<= 1;
2483 				if (nfsi->attrtimeo > NFS_MAXATTRTIMEO(inode))
2484 					nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
2485 			}
2486 			nfsi->attrtimeo_timestamp = now;
2487 		}
2488 		/* Set the barrier to be more recent than this fattr */
2489 		if ((long)(fattr->gencount - nfsi->attr_gencount) > 0)
2490 			nfsi->attr_gencount = fattr->gencount;
2491 	}
2492 
2493 	/* Don't invalidate the data if we were to blame */
2494 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
2495 				|| S_ISLNK(inode->i_mode)))
2496 		invalid &= ~NFS_INO_INVALID_DATA;
2497 	nfs_set_cache_invalid(inode, invalid);
2498 
2499 	return 0;
2500  out_err:
2501 	/*
2502 	 * No need to worry about unhashing the dentry, as the
2503 	 * lookup validation will know that the inode is bad.
2504 	 * (But we fall through to invalidate the caches.)
2505 	 */
2506 	nfs_set_inode_stale_locked(inode);
2507 	return -ESTALE;
2508 }
2509 
nfs_alloc_inode(struct super_block * sb)2510 struct inode *nfs_alloc_inode(struct super_block *sb)
2511 {
2512 	struct nfs_inode *nfsi;
2513 	nfsi = alloc_inode_sb(sb, nfs_inode_cachep, GFP_KERNEL);
2514 	if (!nfsi)
2515 		return NULL;
2516 	nfsi->flags = 0UL;
2517 	nfsi->cache_validity = 0UL;
2518 	nfsi->ooo = NULL;
2519 #if IS_ENABLED(CONFIG_NFS_V4)
2520 	nfsi->nfs4_acl = NULL;
2521 #endif /* CONFIG_NFS_V4 */
2522 #ifdef CONFIG_NFS_V4_2
2523 	nfsi->xattr_cache = NULL;
2524 #endif
2525 	nfs_netfs_inode_init(nfsi);
2526 
2527 	return &nfsi->vfs_inode;
2528 }
2529 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
2530 
nfs_free_inode(struct inode * inode)2531 void nfs_free_inode(struct inode *inode)
2532 {
2533 	kfree(NFS_I(inode)->ooo);
2534 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
2535 }
2536 EXPORT_SYMBOL_GPL(nfs_free_inode);
2537 
nfs4_init_once(struct nfs_inode * nfsi)2538 static inline void nfs4_init_once(struct nfs_inode *nfsi)
2539 {
2540 #if IS_ENABLED(CONFIG_NFS_V4)
2541 	INIT_LIST_HEAD(&nfsi->open_states);
2542 	nfsi->delegation = NULL;
2543 	init_rwsem(&nfsi->rwsem);
2544 	nfsi->layout = NULL;
2545 #endif
2546 }
2547 
init_once(void * foo)2548 static void init_once(void *foo)
2549 {
2550 	struct nfs_inode *nfsi = foo;
2551 
2552 	inode_init_once(&nfsi->vfs_inode);
2553 	INIT_LIST_HEAD(&nfsi->open_files);
2554 	INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
2555 	INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
2556 	nfs4_init_once(nfsi);
2557 }
2558 
nfs_init_inodecache(void)2559 static int __init nfs_init_inodecache(void)
2560 {
2561 	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
2562 					     sizeof(struct nfs_inode),
2563 					     0, (SLAB_RECLAIM_ACCOUNT|
2564 						SLAB_ACCOUNT),
2565 					     init_once);
2566 	if (nfs_inode_cachep == NULL)
2567 		return -ENOMEM;
2568 
2569 	return 0;
2570 }
2571 
nfs_destroy_inodecache(void)2572 static void nfs_destroy_inodecache(void)
2573 {
2574 	/*
2575 	 * Make sure all delayed rcu free inodes are flushed before we
2576 	 * destroy cache.
2577 	 */
2578 	rcu_barrier();
2579 	kmem_cache_destroy(nfs_inode_cachep);
2580 }
2581 
2582 struct workqueue_struct *nfslocaliod_workqueue;
2583 struct workqueue_struct *nfsiod_workqueue;
2584 EXPORT_SYMBOL_GPL(nfsiod_workqueue);
2585 
2586 /*
2587  * Destroy the nfsiod workqueues
2588  */
nfsiod_stop(void)2589 static void nfsiod_stop(void)
2590 {
2591 	struct workqueue_struct *wq;
2592 
2593 	wq = nfsiod_workqueue;
2594 	if (wq != NULL) {
2595 		nfsiod_workqueue = NULL;
2596 		destroy_workqueue(wq);
2597 	}
2598 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
2599 	wq = nfslocaliod_workqueue;
2600 	if (wq != NULL) {
2601 		nfslocaliod_workqueue = NULL;
2602 		destroy_workqueue(wq);
2603 	}
2604 #endif /* CONFIG_NFS_LOCALIO */
2605 }
2606 
2607 /*
2608  * Start the nfsiod workqueues
2609  */
nfsiod_start(void)2610 static int nfsiod_start(void)
2611 {
2612 	dprintk("RPC:       creating workqueue nfsiod\n");
2613 	nfsiod_workqueue = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM | WQ_UNBOUND, 0);
2614 	if (nfsiod_workqueue == NULL)
2615 		return -ENOMEM;
2616 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
2617 	/*
2618 	 * localio writes need to use a normal (non-memreclaim) workqueue.
2619 	 * When we start getting low on space, XFS goes and calls flush_work() on
2620 	 * a non-memreclaim work queue, which causes a priority inversion problem.
2621 	 */
2622 	dprintk("RPC:       creating workqueue nfslocaliod\n");
2623 	nfslocaliod_workqueue = alloc_workqueue("nfslocaliod", WQ_UNBOUND, 0);
2624 	if (unlikely(nfslocaliod_workqueue == NULL)) {
2625 		nfsiod_stop();
2626 		return -ENOMEM;
2627 	}
2628 #endif /* CONFIG_NFS_LOCALIO */
2629 	return 0;
2630 }
2631 
2632 unsigned int nfs_net_id;
2633 EXPORT_SYMBOL_GPL(nfs_net_id);
2634 
nfs_net_init(struct net * net)2635 static int nfs_net_init(struct net *net)
2636 {
2637 	struct nfs_net *nn = net_generic(net, nfs_net_id);
2638 	int err;
2639 
2640 	nfs_clients_init(net);
2641 
2642 	if (!rpc_proc_register(net, &nn->rpcstats)) {
2643 		err = -ENOMEM;
2644 		goto err_proc_rpc;
2645 	}
2646 
2647 	err = nfs_fs_proc_net_init(net);
2648 	if (err)
2649 		goto err_proc_nfs;
2650 
2651 	return 0;
2652 
2653 err_proc_nfs:
2654 	rpc_proc_unregister(net, "nfs");
2655 err_proc_rpc:
2656 	nfs_clients_exit(net);
2657 	return err;
2658 }
2659 
nfs_net_exit(struct net * net)2660 static void nfs_net_exit(struct net *net)
2661 {
2662 	rpc_proc_unregister(net, "nfs");
2663 	nfs_fs_proc_net_exit(net);
2664 	nfs_clients_exit(net);
2665 }
2666 
2667 static struct pernet_operations nfs_net_ops = {
2668 	.init = nfs_net_init,
2669 	.exit = nfs_net_exit,
2670 	.id   = &nfs_net_id,
2671 	.size = sizeof(struct nfs_net),
2672 };
2673 
2674 #ifdef CONFIG_KEYS
2675 static struct key *nfs_keyring;
2676 
nfs_init_keyring(void)2677 static int __init nfs_init_keyring(void)
2678 {
2679 	nfs_keyring = keyring_alloc(".nfs",
2680 			     GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
2681 			     current_cred(),
2682 			     (KEY_POS_ALL & ~KEY_POS_SETATTR) |
2683 			     (KEY_USR_ALL & ~KEY_USR_SETATTR),
2684 			     KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
2685 	return PTR_ERR_OR_ZERO(nfs_keyring);
2686 }
2687 
nfs_exit_keyring(void)2688 static void nfs_exit_keyring(void)
2689 {
2690 	key_put(nfs_keyring);
2691 }
2692 #else
nfs_init_keyring(void)2693 static inline int nfs_init_keyring(void)
2694 {
2695 	return 0;
2696 }
2697 
nfs_exit_keyring(void)2698 static inline void nfs_exit_keyring(void)
2699 {
2700 }
2701 #endif /* CONFIG_KEYS */
2702 
2703 /*
2704  * Initialize NFS
2705  */
init_nfs_fs(void)2706 static int __init init_nfs_fs(void)
2707 {
2708 	int err;
2709 
2710 	err = nfs_init_keyring();
2711 	if (err)
2712 		return err;
2713 
2714 	err = nfs_sysfs_init();
2715 	if (err < 0)
2716 		goto out10;
2717 
2718 	err = register_pernet_subsys(&nfs_net_ops);
2719 	if (err < 0)
2720 		goto out9;
2721 
2722 	err = nfsiod_start();
2723 	if (err)
2724 		goto out7;
2725 
2726 	err = nfs_fs_proc_init();
2727 	if (err)
2728 		goto out6;
2729 
2730 	err = nfs_init_nfspagecache();
2731 	if (err)
2732 		goto out5;
2733 
2734 	err = nfs_init_inodecache();
2735 	if (err)
2736 		goto out4;
2737 
2738 	err = nfs_init_readpagecache();
2739 	if (err)
2740 		goto out3;
2741 
2742 	err = nfs_init_writepagecache();
2743 	if (err)
2744 		goto out2;
2745 
2746 	err = nfs_init_directcache();
2747 	if (err)
2748 		goto out1;
2749 
2750 	err = register_nfs_fs();
2751 	if (err)
2752 		goto out0;
2753 
2754 	return 0;
2755 out0:
2756 	nfs_destroy_directcache();
2757 out1:
2758 	nfs_destroy_writepagecache();
2759 out2:
2760 	nfs_destroy_readpagecache();
2761 out3:
2762 	nfs_destroy_inodecache();
2763 out4:
2764 	nfs_destroy_nfspagecache();
2765 out5:
2766 	nfs_fs_proc_exit();
2767 out6:
2768 	nfsiod_stop();
2769 out7:
2770 	unregister_pernet_subsys(&nfs_net_ops);
2771 out9:
2772 	nfs_sysfs_exit();
2773 out10:
2774 	nfs_exit_keyring();
2775 	return err;
2776 }
2777 
exit_nfs_fs(void)2778 static void __exit exit_nfs_fs(void)
2779 {
2780 	nfs_destroy_directcache();
2781 	nfs_destroy_writepagecache();
2782 	nfs_destroy_readpagecache();
2783 	nfs_destroy_inodecache();
2784 	nfs_destroy_nfspagecache();
2785 	unregister_pernet_subsys(&nfs_net_ops);
2786 	unregister_nfs_fs();
2787 	nfs_fs_proc_exit();
2788 	nfsiod_stop();
2789 	nfs_sysfs_exit();
2790 	nfs_exit_keyring();
2791 }
2792 
2793 /* Not quite true; I just maintain it */
2794 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
2795 MODULE_DESCRIPTION("NFS client support");
2796 MODULE_LICENSE("GPL");
2797 module_param(enable_ino64, bool, 0644);
2798 
2799 module_init(init_nfs_fs)
2800 module_exit(exit_nfs_fs)
2801