xref: /linux/fs/nfs/inode.c (revision b85900e91c8402bedc1db14e6d293e26f25d30d4)
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_obj(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_state_read_once(inode) & 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 		bool updated = false;
653 
654 		now = inode_set_ctime_current(inode);
655 		if (!timespec64_equal(&now, &ctime))
656 			updated = true;
657 
658 		inode_set_mtime_to_ts(inode, attr->ia_mtime);
659 		if (!timespec64_equal(&now, &mtime))
660 			updated = true;
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_atime(struct inode * inode)672 static void nfs_update_atime(struct inode *inode)
673 {
674 	inode_update_time(inode, FS_UPD_ATIME, 0);
675 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ATIME;
676 }
677 
nfs_update_mtime(struct inode * inode)678 static void nfs_update_mtime(struct inode *inode)
679 {
680 	inode_update_time(inode, FS_UPD_CMTIME, 0);
681 	NFS_I(inode)->cache_validity &=
682 		~(NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME);
683 }
684 
nfs_update_delegated_atime(struct inode * inode)685 void nfs_update_delegated_atime(struct inode *inode)
686 {
687 	spin_lock(&inode->i_lock);
688 	if (nfs_have_delegated_atime(inode))
689 		nfs_update_atime(inode);
690 	spin_unlock(&inode->i_lock);
691 }
692 
nfs_update_delegated_mtime_locked(struct inode * inode)693 void nfs_update_delegated_mtime_locked(struct inode *inode)
694 {
695 	if (nfs_have_delegated_mtime(inode) ||
696 	    nfs_have_directory_delegation(inode))
697 		nfs_update_mtime(inode);
698 }
699 
nfs_update_delegated_mtime(struct inode * inode)700 void nfs_update_delegated_mtime(struct inode *inode)
701 {
702 	spin_lock(&inode->i_lock);
703 	nfs_update_delegated_mtime_locked(inode);
704 	spin_unlock(&inode->i_lock);
705 }
706 EXPORT_SYMBOL_GPL(nfs_update_delegated_mtime);
707 
708 #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)
709 
710 int
nfs_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * attr)711 nfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
712 	    struct iattr *attr)
713 {
714 	struct inode *inode = d_inode(dentry);
715 	struct nfs_fattr *fattr;
716 	loff_t oldsize;
717 	int error = 0;
718 	kuid_t task_uid = current_fsuid();
719 	kuid_t owner_uid = inode->i_uid;
720 
721 	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
722 
723 	/* skip mode change if it's just for clearing setuid/setgid */
724 	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
725 		attr->ia_valid &= ~ATTR_MODE;
726 
727 	if (S_ISREG(inode->i_mode))
728 		nfs_file_block_o_direct(NFS_I(inode));
729 
730 	oldsize = i_size_read(inode);
731 	if (attr->ia_valid & ATTR_SIZE) {
732 		BUG_ON(!S_ISREG(inode->i_mode));
733 
734 		error = inode_newsize_ok(inode, attr->ia_size);
735 		if (error)
736 			return error;
737 
738 		if (attr->ia_size == oldsize)
739 			attr->ia_valid &= ~ATTR_SIZE;
740 	}
741 
742 	if (nfs_have_delegated_mtime(inode) && attr->ia_valid & ATTR_MTIME) {
743 		spin_lock(&inode->i_lock);
744 		if (attr->ia_valid & ATTR_MTIME_SET) {
745 			if (uid_eq(task_uid, owner_uid)) {
746 				nfs_set_timestamps_to_ts(inode, attr);
747 				attr->ia_valid &= ~(ATTR_MTIME|ATTR_MTIME_SET|
748 						ATTR_ATIME|ATTR_ATIME_SET);
749 			}
750 		} else {
751 			if (attr->ia_valid & ATTR_MTIME)
752 				nfs_update_mtime(inode);
753 			if (attr->ia_valid & ATTR_ATIME)
754 				nfs_update_atime(inode);
755 			attr->ia_valid &= ~(ATTR_MTIME|ATTR_ATIME);
756 		}
757 		spin_unlock(&inode->i_lock);
758 	} else if (nfs_have_delegated_atime(inode) &&
759 		   attr->ia_valid & ATTR_ATIME &&
760 		   !(attr->ia_valid & ATTR_MTIME)) {
761 		if (!(attr->ia_valid & ATTR_ATIME_SET)) {
762 			nfs_update_delegated_atime(inode);
763 			attr->ia_valid &= ~ATTR_ATIME;
764 		}
765 	}
766 
767 	/* Optimization: if the end result is no change, don't RPC */
768 	if (((attr->ia_valid & NFS_VALID_ATTRS) & ~(ATTR_FILE|ATTR_OPEN)) == 0)
769 		return 0;
770 
771 	trace_nfs_setattr_enter(inode);
772 
773 	/* Write all dirty data */
774 	if (S_ISREG(inode->i_mode))
775 		nfs_sync_inode(inode);
776 
777 	fattr = nfs_alloc_fattr_with_label(NFS_SERVER(inode));
778 	if (fattr == NULL) {
779 		error = -ENOMEM;
780 		goto out;
781 	}
782 
783 	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
784 	if (error == 0) {
785 		if (attr->ia_valid & ATTR_SIZE)
786 			nfs_truncate_last_folio(inode->i_mapping, oldsize,
787 						attr->ia_size);
788 		error = nfs_refresh_inode(inode, fattr);
789 	}
790 	nfs_free_fattr(fattr);
791 out:
792 	trace_nfs_setattr_exit(inode, error);
793 	return error;
794 }
795 EXPORT_SYMBOL_GPL(nfs_setattr);
796 
797 /**
798  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
799  * @inode: inode of the file used
800  * @offset: file offset to start truncating
801  *
802  * This is a copy of the common vmtruncate, but with the locking
803  * corrected to take into account the fact that NFS requires
804  * inode->i_size to be updated under the inode->i_lock.
805  * Note: must be called with inode->i_lock held!
806  */
nfs_vmtruncate(struct inode * inode,loff_t offset)807 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
808 {
809 	int err;
810 
811 	err = inode_newsize_ok(inode, offset);
812 	if (err)
813 		goto out;
814 
815 	trace_nfs_size_truncate(inode, offset);
816 	i_size_write(inode, offset);
817 	/* Optimisation */
818 	if (offset == 0) {
819 		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA;
820 		nfs_ooo_clear(NFS_I(inode));
821 	}
822 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE;
823 
824 	spin_unlock(&inode->i_lock);
825 	truncate_pagecache(inode, offset);
826 	nfs_update_delegated_mtime_locked(inode);
827 	spin_lock(&inode->i_lock);
828 out:
829 	return err;
830 }
831 
832 /**
833  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
834  * @inode: pointer to struct inode
835  * @attr: pointer to struct iattr
836  * @fattr: pointer to struct nfs_fattr
837  *
838  * Note: we do this in the *proc.c in order to ensure that
839  *       it works for things like exclusive creates too.
840  */
nfs_setattr_update_inode(struct inode * inode,struct iattr * attr,struct nfs_fattr * fattr)841 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr,
842 		struct nfs_fattr *fattr)
843 {
844 	/* Barrier: bump the attribute generation count. */
845 	nfs_fattr_set_barrier(fattr);
846 
847 	spin_lock(&inode->i_lock);
848 	NFS_I(inode)->attr_gencount = fattr->gencount;
849 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
850 		if (!nfs_have_delegated_mtime(inode))
851 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
852 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_BLOCKS);
853 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
854 		nfs_vmtruncate(inode, attr->ia_size);
855 	}
856 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
857 		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_CTIME;
858 		if ((attr->ia_valid & ATTR_KILL_SUID) != 0 &&
859 		    inode->i_mode & S_ISUID)
860 			inode->i_mode &= ~S_ISUID;
861 		if (setattr_should_drop_sgid(&nop_mnt_idmap, inode))
862 			inode->i_mode &= ~S_ISGID;
863 		if ((attr->ia_valid & ATTR_MODE) != 0) {
864 			int mode = attr->ia_mode & S_IALLUGO;
865 			mode |= inode->i_mode & ~S_IALLUGO;
866 			inode->i_mode = mode;
867 		}
868 		if ((attr->ia_valid & ATTR_UID) != 0)
869 			inode->i_uid = attr->ia_uid;
870 		if ((attr->ia_valid & ATTR_GID) != 0)
871 			inode->i_gid = attr->ia_gid;
872 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
873 			inode_set_ctime_to_ts(inode, fattr->ctime);
874 		else
875 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
876 					| NFS_INO_INVALID_CTIME);
877 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS
878 				| NFS_INO_INVALID_ACL);
879 	}
880 	if (attr->ia_valid & (ATTR_ATIME_SET|ATTR_ATIME)) {
881 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_ATIME
882 				| NFS_INO_INVALID_CTIME);
883 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
884 			inode_set_atime_to_ts(inode, fattr->atime);
885 		else if (attr->ia_valid & ATTR_ATIME_SET)
886 			inode_set_atime_to_ts(inode, attr->ia_atime);
887 		else
888 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
889 
890 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
891 			inode_set_ctime_to_ts(inode, fattr->ctime);
892 		else
893 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
894 					| NFS_INO_INVALID_CTIME);
895 	}
896 	if (attr->ia_valid & (ATTR_MTIME_SET|ATTR_MTIME)) {
897 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_MTIME
898 				| NFS_INO_INVALID_CTIME);
899 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
900 			inode_set_mtime_to_ts(inode, fattr->mtime);
901 		else if (attr->ia_valid & ATTR_MTIME_SET)
902 			inode_set_mtime_to_ts(inode, attr->ia_mtime);
903 		else
904 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
905 
906 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
907 			inode_set_ctime_to_ts(inode, fattr->ctime);
908 		else
909 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
910 					| NFS_INO_INVALID_CTIME);
911 	}
912 	if (fattr->valid)
913 		nfs_update_inode(inode, fattr);
914 	spin_unlock(&inode->i_lock);
915 }
916 EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
917 
918 /*
919  * Don't request help from readdirplus if the file is being written to,
920  * or if attribute caching is turned off
921  */
nfs_getattr_readdirplus_enable(const struct inode * inode)922 static bool nfs_getattr_readdirplus_enable(const struct inode *inode)
923 {
924 	return nfs_server_capable(inode, NFS_CAP_READDIRPLUS) &&
925 	       !nfs_have_writebacks(inode) && NFS_MAXATTRTIMEO(inode) > 5 * HZ;
926 }
927 
nfs_readdirplus_parent_cache_miss(struct dentry * dentry)928 static void nfs_readdirplus_parent_cache_miss(struct dentry *dentry)
929 {
930 	if (!IS_ROOT(dentry)) {
931 		struct dentry *parent = dget_parent(dentry);
932 		nfs_readdir_record_entry_cache_miss(d_inode(parent));
933 		dput(parent);
934 	}
935 }
936 
nfs_readdirplus_parent_cache_hit(struct dentry * dentry)937 static void nfs_readdirplus_parent_cache_hit(struct dentry *dentry)
938 {
939 	if (!IS_ROOT(dentry)) {
940 		struct dentry *parent = dget_parent(dentry);
941 		nfs_readdir_record_entry_cache_hit(d_inode(parent));
942 		dput(parent);
943 	}
944 }
945 
nfs_get_valid_attrmask(struct inode * inode)946 static u32 nfs_get_valid_attrmask(struct inode *inode)
947 {
948 	u64 fattr_valid = NFS_SERVER(inode)->fattr_valid;
949 	unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
950 	u32 reply_mask = STATX_INO | STATX_TYPE;
951 
952 	if (!(cache_validity & NFS_INO_INVALID_ATIME))
953 		reply_mask |= STATX_ATIME;
954 	if (!(cache_validity & NFS_INO_INVALID_CTIME))
955 		reply_mask |= STATX_CTIME;
956 	if (!(cache_validity & NFS_INO_INVALID_MTIME))
957 		reply_mask |= STATX_MTIME;
958 	if (!(cache_validity & NFS_INO_INVALID_SIZE))
959 		reply_mask |= STATX_SIZE;
960 	if (!(cache_validity & NFS_INO_INVALID_NLINK))
961 		reply_mask |= STATX_NLINK;
962 	if (!(cache_validity & NFS_INO_INVALID_MODE))
963 		reply_mask |= STATX_MODE;
964 	if (!(cache_validity & NFS_INO_INVALID_OTHER))
965 		reply_mask |= STATX_UID | STATX_GID;
966 	if (!(cache_validity & NFS_INO_INVALID_BLOCKS))
967 		reply_mask |= STATX_BLOCKS;
968 	if (!(cache_validity & NFS_INO_INVALID_BTIME) &&
969 	    (fattr_valid & NFS_ATTR_FATTR_BTIME))
970 		reply_mask |= STATX_BTIME;
971 	if (!(cache_validity & NFS_INO_INVALID_CHANGE))
972 		reply_mask |= STATX_CHANGE_COOKIE;
973 	return reply_mask;
974 }
975 
nfs_getattr(struct mnt_idmap * idmap,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)976 int nfs_getattr(struct mnt_idmap *idmap, const struct path *path,
977 		struct kstat *stat, u32 request_mask, unsigned int query_flags)
978 {
979 	struct inode *inode = d_inode(path->dentry);
980 	struct nfs_server *server = NFS_SERVER(inode);
981 	u64 fattr_valid = server->fattr_valid;
982 	unsigned long cache_validity;
983 	int err = 0;
984 	bool force_sync = query_flags & AT_STATX_FORCE_SYNC;
985 	bool do_update = false;
986 	bool readdirplus_enabled = nfs_getattr_readdirplus_enable(inode);
987 
988 	trace_nfs_getattr_enter(inode);
989 
990 	request_mask &= STATX_TYPE | STATX_MODE | STATX_NLINK | STATX_UID |
991 			STATX_GID | STATX_ATIME | STATX_MTIME | STATX_CTIME |
992 			STATX_INO | STATX_SIZE | STATX_BLOCKS | STATX_BTIME |
993 			STATX_CHANGE_COOKIE;
994 
995 	if (!(fattr_valid & NFS_ATTR_FATTR_BTIME))
996 		request_mask &= ~STATX_BTIME;
997 
998 	if ((query_flags & AT_STATX_DONT_SYNC) && !force_sync) {
999 		if (readdirplus_enabled)
1000 			nfs_readdirplus_parent_cache_hit(path->dentry);
1001 		goto out_no_revalidate;
1002 	}
1003 
1004 	/* Flush out writes to the server in order to update c/mtime/version.  */
1005 	if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_CHANGE_COOKIE)) &&
1006 	    S_ISREG(inode->i_mode)) {
1007 		if (nfs_have_delegated_mtime(inode))
1008 			filemap_fdatawrite(inode->i_mapping);
1009 		else
1010 			filemap_write_and_wait(inode->i_mapping);
1011 	}
1012 
1013 	/*
1014 	 * We may force a getattr if the user cares about atime.
1015 	 *
1016 	 * Note that we only have to check the vfsmount flags here:
1017 	 *  - NFS always sets S_NOATIME by so checking it would give a
1018 	 *    bogus result
1019 	 *  - NFS never sets SB_NOATIME or SB_NODIRATIME so there is
1020 	 *    no point in checking those.
1021 	 */
1022 	if ((path->mnt->mnt_flags & MNT_NOATIME) ||
1023 	    ((path->mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
1024 		request_mask &= ~STATX_ATIME;
1025 
1026 	/* Is the user requesting attributes that might need revalidation? */
1027 	if (!(request_mask & (STATX_MODE|STATX_NLINK|STATX_ATIME|STATX_CTIME|
1028 					STATX_MTIME|STATX_UID|STATX_GID|
1029 					STATX_SIZE|STATX_BLOCKS|STATX_BTIME|
1030 					STATX_CHANGE_COOKIE)))
1031 		goto out_no_revalidate;
1032 
1033 	/* Check whether the cached attributes are stale */
1034 	do_update |= force_sync || nfs_attribute_cache_expired(inode);
1035 	cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
1036 	do_update |= cache_validity & NFS_INO_INVALID_CHANGE;
1037 	if (request_mask & STATX_ATIME)
1038 		do_update |= cache_validity & NFS_INO_INVALID_ATIME;
1039 	if (request_mask & STATX_CTIME)
1040 		do_update |= cache_validity & NFS_INO_INVALID_CTIME;
1041 	if (request_mask & STATX_MTIME)
1042 		do_update |= cache_validity & NFS_INO_INVALID_MTIME;
1043 	if (request_mask & STATX_SIZE)
1044 		do_update |= cache_validity & NFS_INO_INVALID_SIZE;
1045 	if (request_mask & STATX_NLINK)
1046 		do_update |= cache_validity & NFS_INO_INVALID_NLINK;
1047 	if (request_mask & STATX_MODE)
1048 		do_update |= cache_validity & NFS_INO_INVALID_MODE;
1049 	if (request_mask & (STATX_UID | STATX_GID))
1050 		do_update |= cache_validity & NFS_INO_INVALID_OTHER;
1051 	if (request_mask & STATX_BLOCKS)
1052 		do_update |= cache_validity & NFS_INO_INVALID_BLOCKS;
1053 	if (request_mask & STATX_BTIME)
1054 		do_update |= cache_validity & NFS_INO_INVALID_BTIME;
1055 
1056 	if (do_update) {
1057 		if (readdirplus_enabled)
1058 			nfs_readdirplus_parent_cache_miss(path->dentry);
1059 		err = __nfs_revalidate_inode(server, inode);
1060 		if (err)
1061 			goto out;
1062 	} else if (readdirplus_enabled)
1063 		nfs_readdirplus_parent_cache_hit(path->dentry);
1064 out_no_revalidate:
1065 	/* Only return attributes that were revalidated. */
1066 	stat->result_mask = nfs_get_valid_attrmask(inode) | request_mask;
1067 
1068 	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
1069 	stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
1070 	stat->change_cookie = inode_peek_iversion_raw(inode);
1071 	stat->attributes_mask |= STATX_ATTR_CHANGE_MONOTONIC;
1072 	if (server->change_attr_type != NFS4_CHANGE_TYPE_IS_UNDEFINED)
1073 		stat->attributes |= STATX_ATTR_CHANGE_MONOTONIC;
1074 	if (S_ISDIR(inode->i_mode))
1075 		stat->blksize = NFS_SERVER(inode)->dtsize;
1076 	stat->btime = NFS_I(inode)->btime;
1077 
1078 	/* Special handling for STATX_DIOALIGN and STATX_DIO_READ_ALIGN
1079 	 * - NFS doesn't have DIO alignment constraints, avoid getting
1080 	 *   these DIO attrs from remote and just respond with most
1081 	 *   accommodating limits (so client will issue supported DIO).
1082 	 * - this is unintuitive, but the most coarse-grained
1083 	 *   dio_offset_align is the most accommodating.
1084 	 */
1085 	if ((request_mask & (STATX_DIOALIGN | STATX_DIO_READ_ALIGN)) &&
1086 	    S_ISREG(inode->i_mode)) {
1087 		stat->result_mask |= STATX_DIOALIGN | STATX_DIO_READ_ALIGN;
1088 		stat->dio_mem_align = 4; /* 4-byte alignment */
1089 		stat->dio_offset_align = PAGE_SIZE;
1090 		stat->dio_read_offset_align = stat->dio_offset_align;
1091 	}
1092 out:
1093 	trace_nfs_getattr_exit(inode, err);
1094 	return err;
1095 }
1096 EXPORT_SYMBOL_GPL(nfs_getattr);
1097 
nfs_init_lock_context(struct nfs_lock_context * l_ctx)1098 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
1099 {
1100 	refcount_set(&l_ctx->count, 1);
1101 	l_ctx->lockowner = current->files;
1102 	INIT_LIST_HEAD(&l_ctx->list);
1103 	atomic_set(&l_ctx->io_count, 0);
1104 }
1105 
__nfs_find_lock_context(struct nfs_open_context * ctx)1106 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
1107 {
1108 	struct nfs_lock_context *pos;
1109 
1110 	list_for_each_entry_rcu(pos, &ctx->lock_context.list, list) {
1111 		if (pos->lockowner != current->files)
1112 			continue;
1113 		if (refcount_inc_not_zero(&pos->count))
1114 			return pos;
1115 	}
1116 	return NULL;
1117 }
1118 
nfs_get_lock_context(struct nfs_open_context * ctx)1119 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
1120 {
1121 	struct nfs_lock_context *res, *new = NULL;
1122 	struct inode *inode = d_inode(ctx->dentry);
1123 
1124 	rcu_read_lock();
1125 	res = __nfs_find_lock_context(ctx);
1126 	rcu_read_unlock();
1127 	if (res == NULL) {
1128 		new = kmalloc_obj(*new, GFP_KERNEL_ACCOUNT);
1129 		if (new == NULL)
1130 			return ERR_PTR(-ENOMEM);
1131 		nfs_init_lock_context(new);
1132 		spin_lock(&inode->i_lock);
1133 		res = __nfs_find_lock_context(ctx);
1134 		if (res == NULL) {
1135 			new->open_context = get_nfs_open_context(ctx);
1136 			if (new->open_context) {
1137 				list_add_tail_rcu(&new->list,
1138 						&ctx->lock_context.list);
1139 				res = new;
1140 				new = NULL;
1141 			} else
1142 				res = ERR_PTR(-EBADF);
1143 		}
1144 		spin_unlock(&inode->i_lock);
1145 		kfree(new);
1146 	}
1147 	return res;
1148 }
1149 EXPORT_SYMBOL_GPL(nfs_get_lock_context);
1150 
nfs_put_lock_context(struct nfs_lock_context * l_ctx)1151 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
1152 {
1153 	struct nfs_open_context *ctx = l_ctx->open_context;
1154 	struct inode *inode = d_inode(ctx->dentry);
1155 
1156 	if (!refcount_dec_and_lock(&l_ctx->count, &inode->i_lock))
1157 		return;
1158 	list_del_rcu(&l_ctx->list);
1159 	spin_unlock(&inode->i_lock);
1160 	put_nfs_open_context(ctx);
1161 	kfree_rcu(l_ctx, rcu_head);
1162 }
1163 EXPORT_SYMBOL_GPL(nfs_put_lock_context);
1164 
1165 /**
1166  * nfs_close_context - Common close_context() routine NFSv2/v3
1167  * @ctx: pointer to context
1168  * @is_sync: is this a synchronous close
1169  *
1170  * Ensure that the attributes are up to date if we're mounted
1171  * with close-to-open semantics and we have cached data that will
1172  * need to be revalidated on open.
1173  */
nfs_close_context(struct nfs_open_context * ctx,int is_sync)1174 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
1175 {
1176 	struct nfs_inode *nfsi;
1177 	struct inode *inode;
1178 
1179 	if (!(ctx->mode & FMODE_WRITE))
1180 		return;
1181 	if (!is_sync)
1182 		return;
1183 	inode = d_inode(ctx->dentry);
1184 	if (nfs_have_read_or_write_delegation(inode))
1185 		return;
1186 	nfsi = NFS_I(inode);
1187 	if (inode->i_mapping->nrpages == 0)
1188 		return;
1189 	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1190 		return;
1191 	if (!list_empty(&nfsi->open_files))
1192 		return;
1193 	if (NFS_SERVER(inode)->flags & NFS_MOUNT_NOCTO)
1194 		return;
1195 	nfs_revalidate_inode(inode,
1196 			     NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_SIZE);
1197 }
1198 EXPORT_SYMBOL_GPL(nfs_close_context);
1199 
alloc_nfs_open_context(struct dentry * dentry,fmode_t f_mode,struct file * filp)1200 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry,
1201 						fmode_t f_mode,
1202 						struct file *filp)
1203 {
1204 	struct nfs_open_context *ctx;
1205 
1206 	ctx = kmalloc_obj(*ctx, GFP_KERNEL_ACCOUNT);
1207 	if (!ctx)
1208 		return ERR_PTR(-ENOMEM);
1209 	nfs_sb_active(dentry->d_sb);
1210 	ctx->dentry = dget(dentry);
1211 	if (filp)
1212 		ctx->cred = get_cred(filp->f_cred);
1213 	else
1214 		ctx->cred = get_current_cred();
1215 	rcu_assign_pointer(ctx->ll_cred, NULL);
1216 	ctx->state = NULL;
1217 	ctx->mode = f_mode;
1218 	ctx->flags = 0;
1219 	ctx->error = 0;
1220 	ctx->flock_owner = (fl_owner_t)filp;
1221 	nfs_init_lock_context(&ctx->lock_context);
1222 	ctx->lock_context.open_context = ctx;
1223 	INIT_LIST_HEAD(&ctx->list);
1224 	ctx->mdsthreshold = NULL;
1225 	nfs_localio_file_init(&ctx->nfl);
1226 
1227 	return ctx;
1228 }
1229 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
1230 
get_nfs_open_context(struct nfs_open_context * ctx)1231 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
1232 {
1233 	if (ctx != NULL && refcount_inc_not_zero(&ctx->lock_context.count))
1234 		return ctx;
1235 	return NULL;
1236 }
1237 EXPORT_SYMBOL_GPL(get_nfs_open_context);
1238 
__put_nfs_open_context(struct nfs_open_context * ctx,int is_sync)1239 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
1240 {
1241 	struct inode *inode = d_inode(ctx->dentry);
1242 	struct super_block *sb = ctx->dentry->d_sb;
1243 
1244 	if (!refcount_dec_and_test(&ctx->lock_context.count))
1245 		return;
1246 	if (!list_empty(&ctx->list)) {
1247 		spin_lock(&inode->i_lock);
1248 		list_del_rcu(&ctx->list);
1249 		spin_unlock(&inode->i_lock);
1250 	}
1251 	if (inode != NULL)
1252 		NFS_PROTO(inode)->close_context(ctx, is_sync);
1253 	put_cred(ctx->cred);
1254 	dput(ctx->dentry);
1255 	nfs_sb_deactive(sb);
1256 	put_rpccred(rcu_dereference_protected(ctx->ll_cred, 1));
1257 	kfree(ctx->mdsthreshold);
1258 	nfs_close_local_fh(&ctx->nfl);
1259 	kfree_rcu(ctx, rcu_head);
1260 }
1261 
put_nfs_open_context(struct nfs_open_context * ctx)1262 void put_nfs_open_context(struct nfs_open_context *ctx)
1263 {
1264 	__put_nfs_open_context(ctx, 0);
1265 }
1266 EXPORT_SYMBOL_GPL(put_nfs_open_context);
1267 
put_nfs_open_context_sync(struct nfs_open_context * ctx)1268 static void put_nfs_open_context_sync(struct nfs_open_context *ctx)
1269 {
1270 	__put_nfs_open_context(ctx, 1);
1271 }
1272 
1273 /*
1274  * Ensure that mmap has a recent RPC credential for use when writing out
1275  * shared pages
1276  */
nfs_inode_attach_open_context(struct nfs_open_context * ctx)1277 void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
1278 {
1279 	struct inode *inode = d_inode(ctx->dentry);
1280 	struct nfs_inode *nfsi = NFS_I(inode);
1281 
1282 	spin_lock(&inode->i_lock);
1283 	if (list_empty(&nfsi->open_files) &&
1284 	    nfs_ooo_test(nfsi))
1285 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA |
1286 						     NFS_INO_REVAL_FORCED);
1287 	list_add_tail_rcu(&ctx->list, &nfsi->open_files);
1288 	spin_unlock(&inode->i_lock);
1289 }
1290 EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
1291 
nfs_file_set_open_context(struct file * filp,struct nfs_open_context * ctx)1292 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
1293 {
1294 	filp->private_data = get_nfs_open_context(ctx);
1295 	set_bit(NFS_CONTEXT_FILE_OPEN, &ctx->flags);
1296 	if (list_empty(&ctx->list))
1297 		nfs_inode_attach_open_context(ctx);
1298 }
1299 EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
1300 
1301 /*
1302  * Given an inode, search for an open context with the desired characteristics
1303  */
nfs_find_open_context(struct inode * inode,const struct cred * cred,fmode_t mode)1304 struct nfs_open_context *nfs_find_open_context(struct inode *inode, const struct cred *cred, fmode_t mode)
1305 {
1306 	struct nfs_inode *nfsi = NFS_I(inode);
1307 	struct nfs_open_context *pos, *ctx = NULL;
1308 
1309 	rcu_read_lock();
1310 	list_for_each_entry_rcu(pos, &nfsi->open_files, list) {
1311 		if (cred != NULL && cred_fscmp(pos->cred, cred) != 0)
1312 			continue;
1313 		if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
1314 			continue;
1315 		if (!test_bit(NFS_CONTEXT_FILE_OPEN, &pos->flags))
1316 			continue;
1317 		ctx = get_nfs_open_context(pos);
1318 		if (ctx)
1319 			break;
1320 	}
1321 	rcu_read_unlock();
1322 	return ctx;
1323 }
1324 
nfs_file_clear_open_context(struct file * filp)1325 void nfs_file_clear_open_context(struct file *filp)
1326 {
1327 	struct nfs_open_context *ctx = nfs_file_open_context(filp);
1328 
1329 	if (ctx) {
1330 		struct inode *inode = d_inode(ctx->dentry);
1331 
1332 		clear_bit(NFS_CONTEXT_FILE_OPEN, &ctx->flags);
1333 		/*
1334 		 * We fatal error on write before. Try to writeback
1335 		 * every page again.
1336 		 */
1337 		if (ctx->error < 0)
1338 			invalidate_inode_pages2(inode->i_mapping);
1339 		filp->private_data = NULL;
1340 		put_nfs_open_context_sync(ctx);
1341 	}
1342 }
1343 
1344 /*
1345  * These allocate and release file read/write context information.
1346  */
nfs_open(struct inode * inode,struct file * filp)1347 int nfs_open(struct inode *inode, struct file *filp)
1348 {
1349 	struct nfs_open_context *ctx;
1350 
1351 	ctx = alloc_nfs_open_context(file_dentry(filp),
1352 				     flags_to_mode(filp->f_flags), filp);
1353 	if (IS_ERR(ctx))
1354 		return PTR_ERR(ctx);
1355 	nfs_file_set_open_context(filp, ctx);
1356 	put_nfs_open_context(ctx);
1357 	nfs_fscache_open_file(inode, filp);
1358 	return 0;
1359 }
1360 
1361 /*
1362  * This function is called whenever some part of NFS notices that
1363  * the cached attributes have to be refreshed.
1364  */
1365 int
__nfs_revalidate_inode(struct nfs_server * server,struct inode * inode)1366 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1367 {
1368 	int		 status = -ESTALE;
1369 	struct nfs_fattr *fattr = NULL;
1370 	struct nfs_inode *nfsi = NFS_I(inode);
1371 
1372 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Lu)\n",
1373 		inode->i_sb->s_id, (unsigned long long)NFS_FILEID(inode));
1374 
1375 	trace_nfs_revalidate_inode_enter(inode);
1376 
1377 	if (is_bad_inode(inode))
1378 		goto out;
1379 	if (NFS_STALE(inode))
1380 		goto out;
1381 
1382 	/* pNFS: Attributes aren't updated until we layoutcommit */
1383 	if (S_ISREG(inode->i_mode)) {
1384 		status = pnfs_sync_inode(inode, false);
1385 		if (status)
1386 			goto out;
1387 	} else if (nfs_have_directory_delegation(inode)) {
1388 		status = 0;
1389 		goto out;
1390 	}
1391 
1392 	status = -ENOMEM;
1393 	fattr = nfs_alloc_fattr_with_label(NFS_SERVER(inode));
1394 	if (fattr == NULL)
1395 		goto out;
1396 
1397 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
1398 
1399 	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr, inode);
1400 	if (status != 0) {
1401 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) getattr failed, error=%d\n",
1402 			 inode->i_sb->s_id,
1403 			 (unsigned long long)NFS_FILEID(inode), status);
1404 		switch (status) {
1405 		case -ETIMEDOUT:
1406 			/* A soft timeout occurred. Use cached information? */
1407 			if (server->flags & NFS_MOUNT_SOFTREVAL)
1408 				status = 0;
1409 			break;
1410 		case -ESTALE:
1411 			if (!S_ISDIR(inode->i_mode))
1412 				nfs_set_inode_stale(inode);
1413 			else
1414 				nfs_zap_caches(inode);
1415 		}
1416 		goto out;
1417 	}
1418 
1419 	status = nfs_refresh_inode(inode, fattr);
1420 	if (status) {
1421 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) refresh failed, error=%d\n",
1422 			 inode->i_sb->s_id,
1423 			 (unsigned long long)NFS_FILEID(inode), status);
1424 		goto out;
1425 	}
1426 
1427 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
1428 		nfs_zap_acl_cache(inode);
1429 
1430 	nfs_setsecurity(inode, fattr);
1431 
1432 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) revalidation complete\n",
1433 		inode->i_sb->s_id,
1434 		(unsigned long long)NFS_FILEID(inode));
1435 
1436 out:
1437 	nfs_free_fattr(fattr);
1438 	trace_nfs_revalidate_inode_exit(inode, status);
1439 	return status;
1440 }
1441 
nfs_attribute_cache_expired(struct inode * inode)1442 int nfs_attribute_cache_expired(struct inode *inode)
1443 {
1444 	if (nfs_have_delegated_attributes(inode))
1445 		return 0;
1446 	return nfs_attribute_timeout(inode);
1447 }
1448 
1449 /**
1450  * nfs_revalidate_inode - Revalidate the inode attributes
1451  * @inode: pointer to inode struct
1452  * @flags: cache flags to check
1453  *
1454  * Updates inode attribute information by retrieving the data from the server.
1455  */
nfs_revalidate_inode(struct inode * inode,unsigned long flags)1456 int nfs_revalidate_inode(struct inode *inode, unsigned long flags)
1457 {
1458 	if (!nfs_check_cache_invalid(inode, flags))
1459 		return NFS_STALE(inode) ? -ESTALE : 0;
1460 	return __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1461 }
1462 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
1463 
nfs_invalidate_mapping(struct inode * inode,struct address_space * mapping)1464 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
1465 {
1466 	int ret;
1467 
1468 	nfs_fscache_invalidate(inode, 0);
1469 	if (mapping->nrpages != 0) {
1470 		if (S_ISREG(inode->i_mode)) {
1471 			ret = nfs_sync_mapping(mapping);
1472 			if (ret < 0)
1473 				return ret;
1474 		}
1475 		ret = invalidate_inode_pages2(mapping);
1476 		if (ret < 0)
1477 			return ret;
1478 	}
1479 	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
1480 
1481 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
1482 			inode->i_sb->s_id,
1483 			(unsigned long long)NFS_FILEID(inode));
1484 	return 0;
1485 }
1486 
1487 /**
1488  * nfs_clear_invalid_mapping - Conditionally clear a mapping
1489  * @mapping: pointer to mapping
1490  *
1491  * If the NFS_INO_INVALID_DATA inode flag is set, clear the mapping.
1492  */
nfs_clear_invalid_mapping(struct address_space * mapping)1493 int nfs_clear_invalid_mapping(struct address_space *mapping)
1494 {
1495 	struct inode *inode = mapping->host;
1496 	struct nfs_inode *nfsi = NFS_I(inode);
1497 	unsigned long *bitlock = &nfsi->flags;
1498 	int ret = 0;
1499 
1500 	/*
1501 	 * We must clear NFS_INO_INVALID_DATA first to ensure that
1502 	 * invalidations that come in while we're shooting down the mappings
1503 	 * are respected. But, that leaves a race window where one revalidator
1504 	 * can clear the flag, and then another checks it before the mapping
1505 	 * gets invalidated. Fix that by serializing access to this part of
1506 	 * the function.
1507 	 *
1508 	 * At the same time, we need to allow other tasks to see whether we
1509 	 * might be in the middle of invalidating the pages, so we only set
1510 	 * the bit lock here if it looks like we're going to be doing that.
1511 	 */
1512 	for (;;) {
1513 		ret = wait_on_bit_action(bitlock, NFS_INO_INVALIDATING,
1514 					 nfs_wait_bit_killable,
1515 					 TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
1516 		if (ret)
1517 			goto out;
1518 		smp_rmb(); /* pairs with smp_wmb() below */
1519 		if (test_bit(NFS_INO_INVALIDATING, bitlock))
1520 			continue;
1521 		/* pairs with nfs_set_cache_invalid()'s smp_store_release() */
1522 		if (!(smp_load_acquire(&nfsi->cache_validity) & NFS_INO_INVALID_DATA))
1523 			goto out;
1524 		/* Slow-path that double-checks with spinlock held */
1525 		spin_lock(&inode->i_lock);
1526 		if (test_bit(NFS_INO_INVALIDATING, bitlock)) {
1527 			spin_unlock(&inode->i_lock);
1528 			continue;
1529 		}
1530 		if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1531 			break;
1532 		spin_unlock(&inode->i_lock);
1533 		goto out;
1534 	}
1535 
1536 	set_bit(NFS_INO_INVALIDATING, bitlock);
1537 	smp_wmb();
1538 	nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
1539 	nfs_ooo_clear(nfsi);
1540 	spin_unlock(&inode->i_lock);
1541 	trace_nfs_invalidate_mapping_enter(inode);
1542 	ret = nfs_invalidate_mapping(inode, mapping);
1543 	trace_nfs_invalidate_mapping_exit(inode, ret);
1544 
1545 	clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
1546 	smp_mb__after_atomic();
1547 	wake_up_bit(bitlock, NFS_INO_INVALIDATING);
1548 out:
1549 	return ret;
1550 }
1551 
nfs_mapping_need_revalidate_inode(struct inode * inode)1552 bool nfs_mapping_need_revalidate_inode(struct inode *inode)
1553 {
1554 	return nfs_check_cache_invalid(inode, NFS_INO_INVALID_CHANGE) ||
1555 		NFS_STALE(inode);
1556 }
1557 
nfs_revalidate_mapping_rcu(struct inode * inode)1558 int nfs_revalidate_mapping_rcu(struct inode *inode)
1559 {
1560 	struct nfs_inode *nfsi = NFS_I(inode);
1561 	unsigned long *bitlock = &nfsi->flags;
1562 	int ret = 0;
1563 
1564 	if (IS_SWAPFILE(inode))
1565 		goto out;
1566 	if (nfs_mapping_need_revalidate_inode(inode)) {
1567 		ret = -ECHILD;
1568 		goto out;
1569 	}
1570 	spin_lock(&inode->i_lock);
1571 	if (test_bit(NFS_INO_INVALIDATING, bitlock) ||
1572 	    (nfsi->cache_validity & NFS_INO_INVALID_DATA))
1573 		ret = -ECHILD;
1574 	spin_unlock(&inode->i_lock);
1575 out:
1576 	return ret;
1577 }
1578 
1579 /**
1580  * nfs_revalidate_mapping - Revalidate the pagecache
1581  * @inode: pointer to host inode
1582  * @mapping: pointer to mapping
1583  */
nfs_revalidate_mapping(struct inode * inode,struct address_space * mapping)1584 int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
1585 {
1586 	/* swapfiles are not supposed to be shared. */
1587 	if (IS_SWAPFILE(inode))
1588 		return 0;
1589 
1590 	if (nfs_mapping_need_revalidate_inode(inode)) {
1591 		int ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1592 		if (ret < 0)
1593 			return ret;
1594 	}
1595 
1596 	return nfs_clear_invalid_mapping(mapping);
1597 }
1598 
nfs_file_has_writers(struct nfs_inode * nfsi)1599 static bool nfs_file_has_writers(struct nfs_inode *nfsi)
1600 {
1601 	struct inode *inode = &nfsi->vfs_inode;
1602 
1603 	if (!S_ISREG(inode->i_mode))
1604 		return false;
1605 	if (list_empty(&nfsi->open_files))
1606 		return false;
1607 	return inode_is_open_for_write(inode);
1608 }
1609 
nfs_file_has_buffered_writers(struct nfs_inode * nfsi)1610 static bool nfs_file_has_buffered_writers(struct nfs_inode *nfsi)
1611 {
1612 	return nfs_file_has_writers(nfsi) && nfs_file_io_is_buffered(nfsi);
1613 }
1614 
nfs_wcc_update_inode(struct inode * inode,struct nfs_fattr * fattr)1615 static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1616 {
1617 	struct timespec64 ts;
1618 
1619 	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
1620 			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
1621 			&& inode_eq_iversion_raw(inode, fattr->pre_change_attr)) {
1622 		inode_set_iversion_raw(inode, fattr->change_attr);
1623 		if (S_ISDIR(inode->i_mode))
1624 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1625 		else if (nfs_server_capable(inode, NFS_CAP_XATTR))
1626 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_XATTR);
1627 	}
1628 	/* If we have atomic WCC data, we may update some attributes */
1629 	ts = inode_get_ctime(inode);
1630 	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
1631 			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
1632 			&& timespec64_equal(&ts, &fattr->pre_ctime)) {
1633 		inode_set_ctime_to_ts(inode, fattr->ctime);
1634 	}
1635 
1636 	ts = inode_get_mtime(inode);
1637 	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
1638 			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
1639 			&& timespec64_equal(&ts, &fattr->pre_mtime)) {
1640 		inode_set_mtime_to_ts(inode, fattr->mtime);
1641 	}
1642 	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
1643 			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
1644 			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
1645 			&& !nfs_have_writebacks(inode)) {
1646 		trace_nfs_size_wcc(inode, fattr->size);
1647 		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
1648 	}
1649 }
1650 
1651 /**
1652  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1653  * @inode: pointer to inode
1654  * @fattr: updated attributes
1655  *
1656  * Verifies the attribute cache. If we have just changed the attributes,
1657  * so that fattr carries weak cache consistency data, then it may
1658  * also update the ctime/mtime/change_attribute.
1659  */
nfs_check_inode_attributes(struct inode * inode,struct nfs_fattr * fattr)1660 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1661 {
1662 	struct nfs_inode *nfsi = NFS_I(inode);
1663 	loff_t cur_size, new_isize;
1664 	unsigned long invalid = 0;
1665 	struct timespec64 ts;
1666 
1667 	if (nfs_have_delegated_attributes(inode))
1668 		return 0;
1669 
1670 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
1671 		/* Only a mounted-on-fileid? Just exit */
1672 		if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
1673 			return 0;
1674 	/* Has the inode gone and changed behind our back? */
1675 	} else if (nfsi->fileid != fattr->fileid) {
1676 		/* Is this perhaps the mounted-on fileid? */
1677 		if ((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) &&
1678 		    nfsi->fileid == fattr->mounted_on_fileid)
1679 			return 0;
1680 		return -ESTALE;
1681 	}
1682 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && inode_wrong_type(inode, fattr->mode))
1683 		return -ESTALE;
1684 
1685 
1686 	if (!nfs_file_has_buffered_writers(nfsi)) {
1687 		/* Verify a few of the more important attributes */
1688 		if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 && !inode_eq_iversion_raw(inode, fattr->change_attr))
1689 			invalid |= NFS_INO_INVALID_CHANGE;
1690 
1691 		ts = inode_get_mtime(inode);
1692 		if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec64_equal(&ts, &fattr->mtime))
1693 			invalid |= NFS_INO_INVALID_MTIME;
1694 
1695 		ts = inode_get_ctime(inode);
1696 		if ((fattr->valid & NFS_ATTR_FATTR_CTIME) && !timespec64_equal(&ts, &fattr->ctime))
1697 			invalid |= NFS_INO_INVALID_CTIME;
1698 
1699 		if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1700 			cur_size = i_size_read(inode);
1701 			new_isize = nfs_size_to_loff_t(fattr->size);
1702 			if (cur_size != new_isize)
1703 				invalid |= NFS_INO_INVALID_SIZE;
1704 		}
1705 	}
1706 
1707 	/* Have any file permissions changed? */
1708 	if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
1709 		invalid |= NFS_INO_INVALID_MODE;
1710 	if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && !uid_eq(inode->i_uid, fattr->uid))
1711 		invalid |= NFS_INO_INVALID_OTHER;
1712 	if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && !gid_eq(inode->i_gid, fattr->gid))
1713 		invalid |= NFS_INO_INVALID_OTHER;
1714 
1715 	/* Has the link count changed? */
1716 	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
1717 		invalid |= NFS_INO_INVALID_NLINK;
1718 
1719 	ts = inode_get_atime(inode);
1720 	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec64_equal(&ts, &fattr->atime))
1721 		invalid |= NFS_INO_INVALID_ATIME;
1722 
1723 	if (invalid != 0)
1724 		nfs_set_cache_invalid(inode, invalid);
1725 
1726 	nfsi->read_cache_jiffies = fattr->time_start;
1727 	return 0;
1728 }
1729 
1730 static atomic_long_t nfs_attr_generation_counter;
1731 
nfs_read_attr_generation_counter(void)1732 static unsigned long nfs_read_attr_generation_counter(void)
1733 {
1734 	return atomic_long_read(&nfs_attr_generation_counter);
1735 }
1736 
nfs_inc_attr_generation_counter(void)1737 unsigned long nfs_inc_attr_generation_counter(void)
1738 {
1739 	return atomic_long_inc_return(&nfs_attr_generation_counter);
1740 }
1741 EXPORT_SYMBOL_GPL(nfs_inc_attr_generation_counter);
1742 
nfs_fattr_init(struct nfs_fattr * fattr)1743 void nfs_fattr_init(struct nfs_fattr *fattr)
1744 {
1745 	fattr->valid = 0;
1746 	fattr->time_start = jiffies;
1747 	fattr->gencount = nfs_inc_attr_generation_counter();
1748 	fattr->owner_name = NULL;
1749 	fattr->group_name = NULL;
1750 	fattr->mdsthreshold = NULL;
1751 }
1752 EXPORT_SYMBOL_GPL(nfs_fattr_init);
1753 
1754 /**
1755  * nfs_fattr_set_barrier
1756  * @fattr: attributes
1757  *
1758  * Used to set a barrier after an attribute was updated. This
1759  * barrier ensures that older attributes from RPC calls that may
1760  * have raced with our update cannot clobber these new values.
1761  * Note that you are still responsible for ensuring that other
1762  * operations which change the attribute on the server do not
1763  * collide.
1764  */
nfs_fattr_set_barrier(struct nfs_fattr * fattr)1765 void nfs_fattr_set_barrier(struct nfs_fattr *fattr)
1766 {
1767 	fattr->gencount = nfs_inc_attr_generation_counter();
1768 }
1769 
nfs_alloc_fattr(void)1770 struct nfs_fattr *nfs_alloc_fattr(void)
1771 {
1772 	struct nfs_fattr *fattr;
1773 
1774 	fattr = kmalloc_obj(*fattr);
1775 	if (fattr != NULL) {
1776 		nfs_fattr_init(fattr);
1777 		fattr->label = NULL;
1778 	}
1779 	return fattr;
1780 }
1781 EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
1782 
nfs_alloc_fattr_with_label(struct nfs_server * server)1783 struct nfs_fattr *nfs_alloc_fattr_with_label(struct nfs_server *server)
1784 {
1785 	struct nfs_fattr *fattr = nfs_alloc_fattr();
1786 
1787 	if (!fattr)
1788 		return NULL;
1789 
1790 	fattr->label = nfs4_label_alloc(server, GFP_KERNEL);
1791 	if (IS_ERR(fattr->label)) {
1792 		kfree(fattr);
1793 		return NULL;
1794 	}
1795 
1796 	return fattr;
1797 }
1798 EXPORT_SYMBOL_GPL(nfs_alloc_fattr_with_label);
1799 
nfs_alloc_fhandle(void)1800 struct nfs_fh *nfs_alloc_fhandle(void)
1801 {
1802 	struct nfs_fh *fh;
1803 
1804 	fh = kmalloc_obj(struct nfs_fh);
1805 	if (fh != NULL)
1806 		fh->size = 0;
1807 	return fh;
1808 }
1809 EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
1810 
1811 #ifdef NFS_DEBUG
1812 /*
1813  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1814  *                             in the same way that wireshark does
1815  *
1816  * @fh: file handle
1817  *
1818  * For debugging only.
1819  */
_nfs_display_fhandle_hash(const struct nfs_fh * fh)1820 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1821 {
1822 	/* wireshark uses 32-bit AUTODIN crc and does a bitwise
1823 	 * not on the result */
1824 	return nfs_fhandle_hash(fh);
1825 }
1826 EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
1827 
1828 /*
1829  * _nfs_display_fhandle - display an NFS file handle on the console
1830  *
1831  * @fh: file handle to display
1832  * @caption: display caption
1833  *
1834  * For debugging only.
1835  */
_nfs_display_fhandle(const struct nfs_fh * fh,const char * caption)1836 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1837 {
1838 	unsigned short i;
1839 
1840 	if (fh == NULL || fh->size == 0) {
1841 		printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1842 		return;
1843 	}
1844 
1845 	printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1846 	       caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1847 	for (i = 0; i < fh->size; i += 16) {
1848 		__be32 *pos = (__be32 *)&fh->data[i];
1849 
1850 		switch ((fh->size - i - 1) >> 2) {
1851 		case 0:
1852 			printk(KERN_DEFAULT " %08x\n",
1853 				be32_to_cpup(pos));
1854 			break;
1855 		case 1:
1856 			printk(KERN_DEFAULT " %08x %08x\n",
1857 				be32_to_cpup(pos), be32_to_cpup(pos + 1));
1858 			break;
1859 		case 2:
1860 			printk(KERN_DEFAULT " %08x %08x %08x\n",
1861 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1862 				be32_to_cpup(pos + 2));
1863 			break;
1864 		default:
1865 			printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1866 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1867 				be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1868 		}
1869 	}
1870 }
1871 EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
1872 #endif
1873 
1874 /**
1875  * nfs_inode_attrs_cmp_generic - compare attributes
1876  * @fattr: attributes
1877  * @inode: pointer to inode
1878  *
1879  * Attempt to divine whether or not an RPC call reply carrying stale
1880  * attributes got scheduled after another call carrying updated ones.
1881  * Note also the check for wraparound of 'attr_gencount'
1882  *
1883  * The function returns '1' if it thinks the attributes in @fattr are
1884  * more recent than the ones cached in @inode. Otherwise it returns
1885  * the value '0'.
1886  */
nfs_inode_attrs_cmp_generic(const struct nfs_fattr * fattr,const struct inode * inode)1887 static int nfs_inode_attrs_cmp_generic(const struct nfs_fattr *fattr,
1888 				       const struct inode *inode)
1889 {
1890 	unsigned long attr_gencount = NFS_I(inode)->attr_gencount;
1891 
1892 	return (long)(fattr->gencount - attr_gencount) > 0 ||
1893 	       (long)(attr_gencount - nfs_read_attr_generation_counter()) > 0;
1894 }
1895 
1896 /**
1897  * nfs_inode_attrs_cmp_monotonic - compare attributes
1898  * @fattr: attributes
1899  * @inode: pointer to inode
1900  *
1901  * Attempt to divine whether or not an RPC call reply carrying stale
1902  * attributes got scheduled after another call carrying updated ones.
1903  *
1904  * We assume that the server observes monotonic semantics for
1905  * the change attribute, so a larger value means that the attributes in
1906  * @fattr are more recent, in which case the function returns the
1907  * value '1'.
1908  * A return value of '0' indicates no measurable change
1909  * A return value of '-1' means that the attributes in @inode are
1910  * more recent.
1911  */
nfs_inode_attrs_cmp_monotonic(const struct nfs_fattr * fattr,const struct inode * inode)1912 static int nfs_inode_attrs_cmp_monotonic(const struct nfs_fattr *fattr,
1913 					 const struct inode *inode)
1914 {
1915 	s64 diff = fattr->change_attr - inode_peek_iversion_raw(inode);
1916 	if (diff > 0)
1917 		return 1;
1918 	return diff == 0 ? 0 : -1;
1919 }
1920 
1921 /**
1922  * nfs_inode_attrs_cmp_strict_monotonic - compare attributes
1923  * @fattr: attributes
1924  * @inode: pointer to inode
1925  *
1926  * Attempt to divine whether or not an RPC call reply carrying stale
1927  * attributes got scheduled after another call carrying updated ones.
1928  *
1929  * We assume that the server observes strictly monotonic semantics for
1930  * the change attribute, so a larger value means that the attributes in
1931  * @fattr are more recent, in which case the function returns the
1932  * value '1'.
1933  * A return value of '-1' means that the attributes in @inode are
1934  * more recent or unchanged.
1935  */
nfs_inode_attrs_cmp_strict_monotonic(const struct nfs_fattr * fattr,const struct inode * inode)1936 static int nfs_inode_attrs_cmp_strict_monotonic(const struct nfs_fattr *fattr,
1937 						const struct inode *inode)
1938 {
1939 	return  nfs_inode_attrs_cmp_monotonic(fattr, inode) > 0 ? 1 : -1;
1940 }
1941 
1942 /**
1943  * nfs_inode_attrs_cmp - compare attributes
1944  * @fattr: attributes
1945  * @inode: pointer to inode
1946  *
1947  * This function returns '1' if it thinks the attributes in @fattr are
1948  * more recent than the ones cached in @inode. It returns '-1' if
1949  * the attributes in @inode are more recent than the ones in @fattr,
1950  * and it returns 0 if not sure.
1951  */
nfs_inode_attrs_cmp(const struct nfs_fattr * fattr,const struct inode * inode)1952 static int nfs_inode_attrs_cmp(const struct nfs_fattr *fattr,
1953 			       const struct inode *inode)
1954 {
1955 	if (nfs_inode_attrs_cmp_generic(fattr, inode) > 0)
1956 		return 1;
1957 	switch (NFS_SERVER(inode)->change_attr_type) {
1958 	case NFS4_CHANGE_TYPE_IS_UNDEFINED:
1959 		break;
1960 	case NFS4_CHANGE_TYPE_IS_TIME_METADATA:
1961 		if (!(fattr->valid & NFS_ATTR_FATTR_CHANGE))
1962 			break;
1963 		return nfs_inode_attrs_cmp_monotonic(fattr, inode);
1964 	default:
1965 		if (!(fattr->valid & NFS_ATTR_FATTR_CHANGE))
1966 			break;
1967 		return nfs_inode_attrs_cmp_strict_monotonic(fattr, inode);
1968 	}
1969 	return 0;
1970 }
1971 
1972 /**
1973  * nfs_inode_finish_partial_attr_update - complete a previous inode update
1974  * @fattr: attributes
1975  * @inode: pointer to inode
1976  *
1977  * Returns '1' if the last attribute update left the inode cached
1978  * attributes in a partially unrevalidated state, and @fattr
1979  * matches the change attribute of that partial update.
1980  * Otherwise returns '0'.
1981  */
nfs_inode_finish_partial_attr_update(const struct nfs_fattr * fattr,const struct inode * inode)1982 static int nfs_inode_finish_partial_attr_update(const struct nfs_fattr *fattr,
1983 						const struct inode *inode)
1984 {
1985 	const unsigned long check_valid =
1986 		NFS_INO_INVALID_ATIME | NFS_INO_INVALID_CTIME |
1987 		NFS_INO_INVALID_MTIME | NFS_INO_INVALID_SIZE |
1988 		NFS_INO_INVALID_BLOCKS | NFS_INO_INVALID_OTHER |
1989 		NFS_INO_INVALID_NLINK | NFS_INO_INVALID_BTIME;
1990 	unsigned long cache_validity = NFS_I(inode)->cache_validity;
1991 	enum nfs4_change_attr_type ctype = NFS_SERVER(inode)->change_attr_type;
1992 
1993 	if (ctype != NFS4_CHANGE_TYPE_IS_UNDEFINED &&
1994 	    !(cache_validity & NFS_INO_INVALID_CHANGE) &&
1995 	    (cache_validity & check_valid) != 0 &&
1996 	    (fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1997 	    nfs_inode_attrs_cmp_monotonic(fattr, inode) == 0)
1998 		return 1;
1999 	return 0;
2000 }
2001 
nfs_ooo_merge(struct nfs_inode * nfsi,u64 start,u64 end)2002 static void nfs_ooo_merge(struct nfs_inode *nfsi,
2003 			  u64 start, u64 end)
2004 {
2005 	int i, cnt;
2006 
2007 	if (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER)
2008 		/* No point merging anything */
2009 		return;
2010 
2011 	if (!nfsi->ooo) {
2012 		nfsi->ooo = kmalloc_obj(*nfsi->ooo, GFP_ATOMIC);
2013 		if (!nfsi->ooo) {
2014 			nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
2015 			return;
2016 		}
2017 		nfsi->ooo->cnt = 0;
2018 	}
2019 
2020 	/* add this range, merging if possible */
2021 	cnt = nfsi->ooo->cnt;
2022 	for (i = 0; i < cnt; i++) {
2023 		if (end == nfsi->ooo->gap[i].start)
2024 			end = nfsi->ooo->gap[i].end;
2025 		else if (start == nfsi->ooo->gap[i].end)
2026 			start = nfsi->ooo->gap[i].start;
2027 		else
2028 			continue;
2029 		/* Remove 'i' from table and loop to insert the new range */
2030 		cnt -= 1;
2031 		nfsi->ooo->gap[i] = nfsi->ooo->gap[cnt];
2032 		i = -1;
2033 	}
2034 	if (start != end) {
2035 		if (cnt >= ARRAY_SIZE(nfsi->ooo->gap)) {
2036 			nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
2037 			kfree(nfsi->ooo);
2038 			nfsi->ooo = NULL;
2039 			return;
2040 		}
2041 		nfsi->ooo->gap[cnt].start = start;
2042 		nfsi->ooo->gap[cnt].end = end;
2043 		cnt += 1;
2044 	}
2045 	nfsi->ooo->cnt = cnt;
2046 }
2047 
nfs_ooo_record(struct nfs_inode * nfsi,struct nfs_fattr * fattr)2048 static void nfs_ooo_record(struct nfs_inode *nfsi,
2049 			   struct nfs_fattr *fattr)
2050 {
2051 	/* This reply was out-of-order, so record in the
2052 	 * pre/post change id, possibly cancelling
2053 	 * gaps created when iversion was jumpped forward.
2054 	 */
2055 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) &&
2056 	    (fattr->valid & NFS_ATTR_FATTR_PRECHANGE))
2057 		nfs_ooo_merge(nfsi,
2058 			      fattr->change_attr,
2059 			      fattr->pre_change_attr);
2060 }
2061 
nfs_refresh_inode_locked(struct inode * inode,struct nfs_fattr * fattr)2062 static int nfs_refresh_inode_locked(struct inode *inode,
2063 				    struct nfs_fattr *fattr)
2064 {
2065 	int attr_cmp = nfs_inode_attrs_cmp(fattr, inode);
2066 	int ret = 0;
2067 
2068 	trace_nfs_refresh_inode_enter(inode);
2069 
2070 	if (attr_cmp > 0 || nfs_inode_finish_partial_attr_update(fattr, inode))
2071 		ret = nfs_update_inode(inode, fattr);
2072 	else {
2073 		nfs_ooo_record(NFS_I(inode), fattr);
2074 
2075 		if (attr_cmp == 0)
2076 			ret = nfs_check_inode_attributes(inode, fattr);
2077 	}
2078 
2079 	trace_nfs_refresh_inode_exit(inode, ret);
2080 	return ret;
2081 }
2082 
2083 /**
2084  * nfs_refresh_inode - try to update the inode attribute cache
2085  * @inode: pointer to inode
2086  * @fattr: updated attributes
2087  *
2088  * Check that an RPC call that returned attributes has not overlapped with
2089  * other recent updates of the inode metadata, then decide whether it is
2090  * safe to do a full update of the inode attributes, or whether just to
2091  * call nfs_check_inode_attributes.
2092  */
nfs_refresh_inode(struct inode * inode,struct nfs_fattr * fattr)2093 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
2094 {
2095 	int status;
2096 
2097 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
2098 		return 0;
2099 	spin_lock(&inode->i_lock);
2100 	status = nfs_refresh_inode_locked(inode, fattr);
2101 	spin_unlock(&inode->i_lock);
2102 
2103 	return status;
2104 }
2105 EXPORT_SYMBOL_GPL(nfs_refresh_inode);
2106 
nfs_post_op_update_inode_locked(struct inode * inode,struct nfs_fattr * fattr,unsigned int invalid)2107 static int nfs_post_op_update_inode_locked(struct inode *inode,
2108 		struct nfs_fattr *fattr, unsigned int invalid)
2109 {
2110 	if (S_ISDIR(inode->i_mode))
2111 		invalid |= NFS_INO_INVALID_DATA;
2112 	nfs_set_cache_invalid(inode, invalid);
2113 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
2114 		return 0;
2115 	return nfs_refresh_inode_locked(inode, fattr);
2116 }
2117 
2118 /**
2119  * nfs_post_op_update_inode - try to update the inode attribute cache
2120  * @inode: pointer to inode
2121  * @fattr: updated attributes
2122  *
2123  * After an operation that has changed the inode metadata, mark the
2124  * attribute cache as being invalid, then try to update it.
2125  *
2126  * NB: if the server didn't return any post op attributes, this
2127  * function will force the retrieval of attributes before the next
2128  * NFS request.  Thus it should be used only for operations that
2129  * are expected to change one or more attributes, to avoid
2130  * unnecessary NFS requests and trips through nfs_update_inode().
2131  */
nfs_post_op_update_inode(struct inode * inode,struct nfs_fattr * fattr)2132 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
2133 {
2134 	int status;
2135 
2136 	spin_lock(&inode->i_lock);
2137 	nfs_fattr_set_barrier(fattr);
2138 	status = nfs_post_op_update_inode_locked(inode, fattr,
2139 			NFS_INO_INVALID_CHANGE
2140 			| NFS_INO_INVALID_CTIME
2141 			| NFS_INO_REVAL_FORCED);
2142 	spin_unlock(&inode->i_lock);
2143 
2144 	return status;
2145 }
2146 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
2147 
2148 /**
2149  * nfs_post_op_update_inode_force_wcc_locked - update the inode attribute cache
2150  * @inode: pointer to inode
2151  * @fattr: updated attributes
2152  *
2153  * After an operation that has changed the inode metadata, mark the
2154  * attribute cache as being invalid, then try to update it. Fake up
2155  * weak cache consistency data, if none exist.
2156  *
2157  * This function is mainly designed to be used by the ->write_done() functions.
2158  */
nfs_post_op_update_inode_force_wcc_locked(struct inode * inode,struct nfs_fattr * fattr)2159 int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr)
2160 {
2161 	int attr_cmp = nfs_inode_attrs_cmp(fattr, inode);
2162 	int status;
2163 
2164 	/* Don't do a WCC update if these attributes are already stale */
2165 	if (attr_cmp < 0)
2166 		return 0;
2167 	if ((fattr->valid & NFS_ATTR_FATTR) == 0 || !attr_cmp) {
2168 		/* Record the pre/post change info before clearing PRECHANGE */
2169 		nfs_ooo_record(NFS_I(inode), fattr);
2170 		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
2171 				| NFS_ATTR_FATTR_PRESIZE
2172 				| NFS_ATTR_FATTR_PREMTIME
2173 				| NFS_ATTR_FATTR_PRECTIME);
2174 		goto out_noforce;
2175 	}
2176 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
2177 			(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
2178 		fattr->pre_change_attr = inode_peek_iversion_raw(inode);
2179 		fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
2180 	}
2181 	if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
2182 			(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
2183 		fattr->pre_ctime = inode_get_ctime(inode);
2184 		fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
2185 	}
2186 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
2187 			(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
2188 		fattr->pre_mtime = inode_get_mtime(inode);
2189 		fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
2190 	}
2191 	if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
2192 			(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
2193 		fattr->pre_size = i_size_read(inode);
2194 		fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
2195 	}
2196 out_noforce:
2197 	status = nfs_post_op_update_inode_locked(inode, fattr,
2198 			NFS_INO_INVALID_CHANGE
2199 			| NFS_INO_INVALID_CTIME
2200 			| NFS_INO_INVALID_MTIME
2201 			| NFS_INO_INVALID_BLOCKS);
2202 	return status;
2203 }
2204 
2205 /**
2206  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
2207  * @inode: pointer to inode
2208  * @fattr: updated attributes
2209  *
2210  * After an operation that has changed the inode metadata, mark the
2211  * attribute cache as being invalid, then try to update it. Fake up
2212  * weak cache consistency data, if none exist.
2213  *
2214  * This function is mainly designed to be used by the ->write_done() functions.
2215  */
nfs_post_op_update_inode_force_wcc(struct inode * inode,struct nfs_fattr * fattr)2216 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
2217 {
2218 	int status;
2219 
2220 	spin_lock(&inode->i_lock);
2221 	nfs_fattr_set_barrier(fattr);
2222 	status = nfs_post_op_update_inode_force_wcc_locked(inode, fattr);
2223 	spin_unlock(&inode->i_lock);
2224 	return status;
2225 }
2226 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
2227 
2228 
2229 /*
2230  * Many nfs protocol calls return the new file attributes after
2231  * an operation.  Here we update the inode to reflect the state
2232  * of the server's inode.
2233  *
2234  * This is a bit tricky because we have to make sure all dirty pages
2235  * have been sent off to the server before calling invalidate_inode_pages.
2236  * To make sure no other process adds more write requests while we try
2237  * our best to flush them, we make them sleep during the attribute refresh.
2238  *
2239  * A very similar scenario holds for the dir cache.
2240  */
nfs_update_inode(struct inode * inode,struct nfs_fattr * fattr)2241 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
2242 {
2243 	struct nfs_server *server = NFS_SERVER(inode);
2244 	struct nfs_inode *nfsi = NFS_I(inode);
2245 	loff_t cur_isize, new_isize;
2246 	u64 fattr_supported = server->fattr_valid;
2247 	unsigned long invalid = 0;
2248 	unsigned long now = jiffies;
2249 	unsigned long save_cache_validity;
2250 	bool have_writers = nfs_file_has_buffered_writers(nfsi);
2251 	bool cache_revalidated = true;
2252 	bool attr_changed = false;
2253 	bool have_delegation;
2254 
2255 	dfprintk(VFS, "NFS: %s(%s/%llu fh_crc=0x%08x ct=%d info=0x%llx)\n",
2256 			__func__, inode->i_sb->s_id, inode->i_ino,
2257 			nfs_display_fhandle_hash(NFS_FH(inode)),
2258 			icount_read(inode), fattr->valid);
2259 
2260 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
2261 		/* Only a mounted-on-fileid? Just exit */
2262 		if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
2263 			return 0;
2264 	/* Has the inode gone and changed behind our back? */
2265 	} else if (nfsi->fileid != fattr->fileid) {
2266 		/* Is this perhaps the mounted-on fileid? */
2267 		if ((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) &&
2268 		    nfsi->fileid == fattr->mounted_on_fileid)
2269 			return 0;
2270 		printk(KERN_ERR "NFS: server %s error: fileid changed\n"
2271 			"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
2272 			NFS_SERVER(inode)->nfs_client->cl_hostname,
2273 			inode->i_sb->s_id, (long long)nfsi->fileid,
2274 			(long long)fattr->fileid);
2275 		goto out_err;
2276 	}
2277 
2278 	/*
2279 	 * Make sure the inode's type hasn't changed.
2280 	 */
2281 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && inode_wrong_type(inode, fattr->mode)) {
2282 		/*
2283 		* Big trouble! The inode has become a different object.
2284 		*/
2285 		printk(KERN_DEBUG "NFS: %s: inode %llu mode changed, %07o to %07o\n",
2286 				__func__, inode->i_ino, inode->i_mode, fattr->mode);
2287 		goto out_err;
2288 	}
2289 
2290 	/* Update the fsid? */
2291 	if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
2292 			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
2293 			!IS_AUTOMOUNT(inode))
2294 		server->fsid = fattr->fsid;
2295 
2296 	/* Save the delegation state before clearing cache_validity */
2297 	have_delegation = nfs_have_delegated_attributes(inode);
2298 
2299 	/*
2300 	 * Update the read time so we don't revalidate too often.
2301 	 */
2302 	nfsi->read_cache_jiffies = fattr->time_start;
2303 
2304 	/* Fix up any delegated attributes in the struct nfs_fattr */
2305 	nfs_fattr_fixup_delegated(inode, fattr);
2306 
2307 	save_cache_validity = nfsi->cache_validity;
2308 	nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
2309 			| NFS_INO_INVALID_ATIME
2310 			| NFS_INO_REVAL_FORCED
2311 			| NFS_INO_INVALID_BLOCKS);
2312 
2313 	/* Do atomic weak cache consistency updates */
2314 	nfs_wcc_update_inode(inode, fattr);
2315 
2316 	if (pnfs_layoutcommit_outstanding(inode)) {
2317 		nfsi->cache_validity |=
2318 			save_cache_validity &
2319 			(NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_CTIME |
2320 			 NFS_INO_INVALID_MTIME | NFS_INO_INVALID_SIZE |
2321 			 NFS_INO_INVALID_BLOCKS);
2322 		cache_revalidated = false;
2323 	}
2324 
2325 	/* More cache consistency checks */
2326 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
2327 		if (!have_writers && nfsi->ooo && nfsi->ooo->cnt == 1 &&
2328 		    nfsi->ooo->gap[0].end == inode_peek_iversion_raw(inode)) {
2329 			/* There is one remaining gap that hasn't been
2330 			 * merged into iversion - do that now.
2331 			 */
2332 			inode_set_iversion_raw(inode, nfsi->ooo->gap[0].start);
2333 			kfree(nfsi->ooo);
2334 			nfsi->ooo = NULL;
2335 		}
2336 		if (!inode_eq_iversion_raw(inode, fattr->change_attr)) {
2337 			/* Could it be a race with writeback? */
2338 			if (!(have_writers || have_delegation)) {
2339 				invalid |= NFS_INO_INVALID_DATA
2340 					| NFS_INO_INVALID_ACCESS
2341 					| NFS_INO_INVALID_ACL
2342 					| NFS_INO_INVALID_XATTR;
2343 				/* Force revalidate of all attributes */
2344 				save_cache_validity |= NFS_INO_INVALID_CTIME
2345 					| NFS_INO_INVALID_MTIME
2346 					| NFS_INO_INVALID_SIZE
2347 					| NFS_INO_INVALID_BLOCKS
2348 					| NFS_INO_INVALID_NLINK
2349 					| NFS_INO_INVALID_MODE
2350 					| NFS_INO_INVALID_OTHER
2351 					| NFS_INO_INVALID_BTIME;
2352 				if (S_ISDIR(inode->i_mode))
2353 					nfs_force_lookup_revalidate(inode);
2354 				attr_changed = true;
2355 				dprintk("NFS: change_attr change on server for file %s/%llu\n",
2356 						inode->i_sb->s_id,
2357 						inode->i_ino);
2358 			} else if (!have_delegation) {
2359 				nfs_ooo_record(nfsi, fattr);
2360 				nfs_ooo_merge(nfsi, inode_peek_iversion_raw(inode),
2361 					      fattr->change_attr);
2362 			}
2363 			inode_set_iversion_raw(inode, fattr->change_attr);
2364 		}
2365 	} else {
2366 		nfsi->cache_validity |=
2367 			save_cache_validity & NFS_INO_INVALID_CHANGE;
2368 		if (!have_delegation ||
2369 		    (nfsi->cache_validity & NFS_INO_INVALID_CHANGE) != 0)
2370 			cache_revalidated = false;
2371 	}
2372 
2373 	if (fattr->valid & NFS_ATTR_FATTR_MTIME)
2374 		inode_set_mtime_to_ts(inode, fattr->mtime);
2375 	else if (fattr_supported & NFS_ATTR_FATTR_MTIME)
2376 		nfsi->cache_validity |=
2377 			save_cache_validity & NFS_INO_INVALID_MTIME;
2378 
2379 	if (fattr->valid & NFS_ATTR_FATTR_CTIME)
2380 		inode_set_ctime_to_ts(inode, fattr->ctime);
2381 	else if (fattr_supported & NFS_ATTR_FATTR_CTIME)
2382 		nfsi->cache_validity |=
2383 			save_cache_validity & NFS_INO_INVALID_CTIME;
2384 
2385 	if (fattr->valid & NFS_ATTR_FATTR_BTIME)
2386 		nfsi->btime = fattr->btime;
2387 	else if (fattr_supported & NFS_ATTR_FATTR_BTIME)
2388 		nfsi->cache_validity |=
2389 			save_cache_validity & NFS_INO_INVALID_BTIME;
2390 
2391 	/* Check if our cached file size is stale */
2392 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
2393 		new_isize = nfs_size_to_loff_t(fattr->size);
2394 		cur_isize = i_size_read(inode);
2395 		if (new_isize != cur_isize && !have_delegation) {
2396 			/* Do we perhaps have any outstanding writes, or has
2397 			 * the file grown beyond our last write? */
2398 			if (!nfs_have_writebacks(inode) || new_isize > cur_isize) {
2399 				trace_nfs_size_update(inode, new_isize);
2400 				i_size_write(inode, new_isize);
2401 				if (!have_writers)
2402 					invalid |= NFS_INO_INVALID_DATA;
2403 			}
2404 		}
2405 		if (new_isize == 0 &&
2406 		    !(fattr->valid & (NFS_ATTR_FATTR_SPACE_USED |
2407 				      NFS_ATTR_FATTR_BLOCKS_USED))) {
2408 			fattr->du.nfs3.used = 0;
2409 			fattr->valid |= NFS_ATTR_FATTR_SPACE_USED;
2410 		}
2411 	} else
2412 		nfsi->cache_validity |=
2413 			save_cache_validity & NFS_INO_INVALID_SIZE;
2414 
2415 	if (fattr->valid & NFS_ATTR_FATTR_ATIME)
2416 		inode_set_atime_to_ts(inode, fattr->atime);
2417 	else if (fattr_supported & NFS_ATTR_FATTR_ATIME)
2418 		nfsi->cache_validity |=
2419 			save_cache_validity & NFS_INO_INVALID_ATIME;
2420 
2421 	if (fattr->valid & NFS_ATTR_FATTR_MODE) {
2422 		if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
2423 			umode_t newmode = inode->i_mode & S_IFMT;
2424 			newmode |= fattr->mode & S_IALLUGO;
2425 			inode->i_mode = newmode;
2426 			invalid |= NFS_INO_INVALID_ACCESS
2427 				| NFS_INO_INVALID_ACL;
2428 		}
2429 	} else if (fattr_supported & NFS_ATTR_FATTR_MODE)
2430 		nfsi->cache_validity |=
2431 			save_cache_validity & NFS_INO_INVALID_MODE;
2432 
2433 	if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
2434 		if (!uid_eq(inode->i_uid, fattr->uid)) {
2435 			invalid |= NFS_INO_INVALID_ACCESS
2436 				| NFS_INO_INVALID_ACL;
2437 			inode->i_uid = fattr->uid;
2438 		}
2439 	} else if (fattr_supported & NFS_ATTR_FATTR_OWNER)
2440 		nfsi->cache_validity |=
2441 			save_cache_validity & NFS_INO_INVALID_OTHER;
2442 
2443 	if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
2444 		if (!gid_eq(inode->i_gid, fattr->gid)) {
2445 			invalid |= NFS_INO_INVALID_ACCESS
2446 				| NFS_INO_INVALID_ACL;
2447 			inode->i_gid = fattr->gid;
2448 		}
2449 	} else if (fattr_supported & NFS_ATTR_FATTR_GROUP)
2450 		nfsi->cache_validity |=
2451 			save_cache_validity & NFS_INO_INVALID_OTHER;
2452 
2453 	if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
2454 		if (inode->i_nlink != fattr->nlink)
2455 			set_nlink(inode, fattr->nlink);
2456 	} else if (fattr_supported & NFS_ATTR_FATTR_NLINK)
2457 		nfsi->cache_validity |=
2458 			save_cache_validity & NFS_INO_INVALID_NLINK;
2459 
2460 	if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
2461 		/*
2462 		 * report the blocks in 512byte units
2463 		 */
2464 		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
2465 	} else if (fattr_supported & NFS_ATTR_FATTR_SPACE_USED)
2466 		nfsi->cache_validity |=
2467 			save_cache_validity & NFS_INO_INVALID_BLOCKS;
2468 
2469 	if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
2470 		inode->i_blocks = fattr->du.nfs2.blocks;
2471 	else if (fattr_supported & NFS_ATTR_FATTR_BLOCKS_USED)
2472 		nfsi->cache_validity |=
2473 			save_cache_validity & NFS_INO_INVALID_BLOCKS;
2474 
2475 	/* Update attrtimeo value if we're out of the unstable period */
2476 	if (attr_changed) {
2477 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
2478 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
2479 		nfsi->attrtimeo_timestamp = now;
2480 		/* Set barrier to be more recent than all outstanding updates */
2481 		nfsi->attr_gencount = nfs_inc_attr_generation_counter();
2482 	} else {
2483 		if (cache_revalidated) {
2484 			if (!time_in_range_open(now, nfsi->attrtimeo_timestamp,
2485 				nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
2486 				nfsi->attrtimeo <<= 1;
2487 				if (nfsi->attrtimeo > NFS_MAXATTRTIMEO(inode))
2488 					nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
2489 			}
2490 			nfsi->attrtimeo_timestamp = now;
2491 		}
2492 		/* Set the barrier to be more recent than this fattr */
2493 		if ((long)(fattr->gencount - nfsi->attr_gencount) > 0)
2494 			nfsi->attr_gencount = fattr->gencount;
2495 	}
2496 
2497 	/* Don't invalidate the data if we were to blame */
2498 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
2499 				|| S_ISLNK(inode->i_mode)))
2500 		invalid &= ~NFS_INO_INVALID_DATA;
2501 	nfs_set_cache_invalid(inode, invalid);
2502 
2503 	return 0;
2504  out_err:
2505 	/*
2506 	 * No need to worry about unhashing the dentry, as the
2507 	 * lookup validation will know that the inode is bad.
2508 	 * (But we fall through to invalidate the caches.)
2509 	 */
2510 	nfs_set_inode_stale_locked(inode);
2511 	return -ESTALE;
2512 }
2513 
nfs_alloc_inode(struct super_block * sb)2514 struct inode *nfs_alloc_inode(struct super_block *sb)
2515 {
2516 	struct nfs_inode *nfsi;
2517 	nfsi = alloc_inode_sb(sb, nfs_inode_cachep, GFP_KERNEL);
2518 	if (!nfsi)
2519 		return NULL;
2520 	nfsi->flags = 0UL;
2521 	nfsi->cache_validity = 0UL;
2522 	nfsi->ooo = NULL;
2523 #if IS_ENABLED(CONFIG_NFS_V4)
2524 	nfsi->nfs4_acl = NULL;
2525 #endif /* CONFIG_NFS_V4 */
2526 #ifdef CONFIG_NFS_V4_2
2527 	nfsi->xattr_cache = NULL;
2528 #endif
2529 	nfs_netfs_inode_init(nfsi);
2530 
2531 	return &nfsi->vfs_inode;
2532 }
2533 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
2534 
nfs_free_inode(struct inode * inode)2535 void nfs_free_inode(struct inode *inode)
2536 {
2537 	kfree(NFS_I(inode)->ooo);
2538 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
2539 }
2540 EXPORT_SYMBOL_GPL(nfs_free_inode);
2541 
nfs4_init_once(struct nfs_inode * nfsi)2542 static inline void nfs4_init_once(struct nfs_inode *nfsi)
2543 {
2544 #if IS_ENABLED(CONFIG_NFS_V4)
2545 	INIT_LIST_HEAD(&nfsi->open_states);
2546 	nfsi->delegation = NULL;
2547 	init_rwsem(&nfsi->rwsem);
2548 	nfsi->layout = NULL;
2549 #endif
2550 }
2551 
init_once(void * foo)2552 static void init_once(void *foo)
2553 {
2554 	struct nfs_inode *nfsi = foo;
2555 
2556 	inode_init_once(&nfsi->vfs_inode);
2557 	INIT_LIST_HEAD(&nfsi->open_files);
2558 	INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
2559 	INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
2560 	nfs4_init_once(nfsi);
2561 }
2562 
nfs_init_inodecache(void)2563 static int __init nfs_init_inodecache(void)
2564 {
2565 	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
2566 					     sizeof(struct nfs_inode),
2567 					     0, (SLAB_RECLAIM_ACCOUNT|
2568 						SLAB_ACCOUNT),
2569 					     init_once);
2570 	if (nfs_inode_cachep == NULL)
2571 		return -ENOMEM;
2572 
2573 	return 0;
2574 }
2575 
nfs_destroy_inodecache(void)2576 static void nfs_destroy_inodecache(void)
2577 {
2578 	/*
2579 	 * Make sure all delayed rcu free inodes are flushed before we
2580 	 * destroy cache.
2581 	 */
2582 	rcu_barrier();
2583 	kmem_cache_destroy(nfs_inode_cachep);
2584 }
2585 
2586 struct workqueue_struct *nfslocaliod_workqueue;
2587 struct workqueue_struct *nfsiod_workqueue;
2588 EXPORT_SYMBOL_GPL(nfsiod_workqueue);
2589 
2590 /*
2591  * Destroy the nfsiod workqueues
2592  */
nfsiod_stop(void)2593 static void nfsiod_stop(void)
2594 {
2595 	struct workqueue_struct *wq;
2596 
2597 	wq = nfsiod_workqueue;
2598 	if (wq != NULL) {
2599 		nfsiod_workqueue = NULL;
2600 		destroy_workqueue(wq);
2601 	}
2602 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
2603 	wq = nfslocaliod_workqueue;
2604 	if (wq != NULL) {
2605 		nfslocaliod_workqueue = NULL;
2606 		destroy_workqueue(wq);
2607 	}
2608 #endif /* CONFIG_NFS_LOCALIO */
2609 }
2610 
2611 /*
2612  * Start the nfsiod workqueues
2613  */
nfsiod_start(void)2614 static int nfsiod_start(void)
2615 {
2616 	dprintk("RPC:       creating workqueue nfsiod\n");
2617 	nfsiod_workqueue = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM | WQ_UNBOUND, 0);
2618 	if (nfsiod_workqueue == NULL)
2619 		return -ENOMEM;
2620 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
2621 	/*
2622 	 * localio writes need to use a normal (non-memreclaim) workqueue.
2623 	 * When we start getting low on space, XFS goes and calls flush_work() on
2624 	 * a non-memreclaim work queue, which causes a priority inversion problem.
2625 	 */
2626 	dprintk("RPC:       creating workqueue nfslocaliod\n");
2627 	nfslocaliod_workqueue = alloc_workqueue("nfslocaliod", WQ_UNBOUND, 0);
2628 	if (unlikely(nfslocaliod_workqueue == NULL)) {
2629 		nfsiod_stop();
2630 		return -ENOMEM;
2631 	}
2632 #endif /* CONFIG_NFS_LOCALIO */
2633 	return 0;
2634 }
2635 
2636 unsigned int nfs_net_id;
2637 EXPORT_SYMBOL_GPL(nfs_net_id);
2638 
nfs_net_init(struct net * net)2639 static int nfs_net_init(struct net *net)
2640 {
2641 	struct nfs_net *nn = net_generic(net, nfs_net_id);
2642 	int err;
2643 
2644 	nfs_clients_init(net);
2645 
2646 	if (!rpc_proc_register(net, &nn->rpcstats)) {
2647 		err = -ENOMEM;
2648 		goto err_proc_rpc;
2649 	}
2650 
2651 	err = nfs_fs_proc_net_init(net);
2652 	if (err)
2653 		goto err_proc_nfs;
2654 
2655 	return 0;
2656 
2657 err_proc_nfs:
2658 	rpc_proc_unregister(net, "nfs");
2659 err_proc_rpc:
2660 	nfs_clients_exit(net);
2661 	return err;
2662 }
2663 
nfs_net_exit(struct net * net)2664 static void nfs_net_exit(struct net *net)
2665 {
2666 	rpc_proc_unregister(net, "nfs");
2667 	nfs_fs_proc_net_exit(net);
2668 	nfs_clients_exit(net);
2669 }
2670 
2671 static struct pernet_operations nfs_net_ops = {
2672 	.init = nfs_net_init,
2673 	.exit = nfs_net_exit,
2674 	.id   = &nfs_net_id,
2675 	.size = sizeof(struct nfs_net),
2676 };
2677 
2678 #ifdef CONFIG_KEYS
2679 static struct key *nfs_keyring;
2680 
nfs_init_keyring(void)2681 static int __init nfs_init_keyring(void)
2682 {
2683 	nfs_keyring = keyring_alloc(".nfs",
2684 			     GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
2685 			     current_cred(),
2686 			     (KEY_POS_ALL & ~KEY_POS_SETATTR) |
2687 			     (KEY_USR_ALL & ~KEY_USR_SETATTR),
2688 			     KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
2689 	return PTR_ERR_OR_ZERO(nfs_keyring);
2690 }
2691 
nfs_exit_keyring(void)2692 static void nfs_exit_keyring(void)
2693 {
2694 	key_put(nfs_keyring);
2695 }
2696 #else
nfs_init_keyring(void)2697 static inline int nfs_init_keyring(void)
2698 {
2699 	return 0;
2700 }
2701 
nfs_exit_keyring(void)2702 static inline void nfs_exit_keyring(void)
2703 {
2704 }
2705 #endif /* CONFIG_KEYS */
2706 
2707 /*
2708  * Initialize NFS
2709  */
init_nfs_fs(void)2710 static int __init init_nfs_fs(void)
2711 {
2712 	int err;
2713 
2714 	err = nfs_init_keyring();
2715 	if (err)
2716 		return err;
2717 
2718 	err = nfs_sysfs_init();
2719 	if (err < 0)
2720 		goto out10;
2721 
2722 	err = register_pernet_subsys(&nfs_net_ops);
2723 	if (err < 0)
2724 		goto out9;
2725 
2726 	err = nfsiod_start();
2727 	if (err)
2728 		goto out7;
2729 
2730 	err = nfs_fs_proc_init();
2731 	if (err)
2732 		goto out6;
2733 
2734 	err = nfs_init_nfspagecache();
2735 	if (err)
2736 		goto out5;
2737 
2738 	err = nfs_init_inodecache();
2739 	if (err)
2740 		goto out4;
2741 
2742 	err = nfs_init_readpagecache();
2743 	if (err)
2744 		goto out3;
2745 
2746 	err = nfs_init_writepagecache();
2747 	if (err)
2748 		goto out2;
2749 
2750 	err = nfs_init_directcache();
2751 	if (err)
2752 		goto out1;
2753 
2754 	err = register_nfs_fs();
2755 	if (err)
2756 		goto out0;
2757 
2758 	return 0;
2759 out0:
2760 	nfs_destroy_directcache();
2761 out1:
2762 	nfs_destroy_writepagecache();
2763 out2:
2764 	nfs_destroy_readpagecache();
2765 out3:
2766 	nfs_destroy_inodecache();
2767 out4:
2768 	nfs_destroy_nfspagecache();
2769 out5:
2770 	nfs_fs_proc_exit();
2771 out6:
2772 	nfsiod_stop();
2773 out7:
2774 	unregister_pernet_subsys(&nfs_net_ops);
2775 out9:
2776 	nfs_sysfs_exit();
2777 out10:
2778 	nfs_exit_keyring();
2779 	return err;
2780 }
2781 
exit_nfs_fs(void)2782 static void __exit exit_nfs_fs(void)
2783 {
2784 	nfs_destroy_directcache();
2785 	nfs_destroy_writepagecache();
2786 	nfs_destroy_readpagecache();
2787 	nfs_destroy_inodecache();
2788 	nfs_destroy_nfspagecache();
2789 	unregister_pernet_subsys(&nfs_net_ops);
2790 	unregister_nfs_fs();
2791 	nfs_fs_proc_exit();
2792 	nfsiod_stop();
2793 	nfs_sysfs_exit();
2794 	nfs_exit_keyring();
2795 }
2796 
2797 /* Not quite true; I just maintain it */
2798 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
2799 MODULE_DESCRIPTION("NFS client support");
2800 MODULE_LICENSE("GPL");
2801 module_param(enable_ino64, bool, 0644);
2802 
2803 module_init(init_nfs_fs)
2804 module_exit(exit_nfs_fs)
2805