xref: /linux/fs/nfs/inode.c (revision 1cc41c88ef00de0f3216c5f4b9cfab47de1c49d3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/fs/nfs/inode.c
4  *
5  *  Copyright (C) 1992  Rick Sladkey
6  *
7  *  nfs inode and superblock handling functions
8  *
9  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
10  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
11  *
12  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
13  *  J.S.Peatfield@damtp.cam.ac.uk
14  *
15  */
16 
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/sched/signal.h>
20 #include <linux/time.h>
21 #include <linux/kernel.h>
22 #include <linux/mm.h>
23 #include <linux/string.h>
24 #include <linux/stat.h>
25 #include <linux/errno.h>
26 #include <linux/unistd.h>
27 #include <linux/sunrpc/clnt.h>
28 #include <linux/sunrpc/stats.h>
29 #include <linux/sunrpc/metrics.h>
30 #include <linux/nfs_fs.h>
31 #include <linux/nfs_mount.h>
32 #include <linux/nfs4_mount.h>
33 #include <linux/lockd/bind.h>
34 #include <linux/seq_file.h>
35 #include <linux/mount.h>
36 #include <linux/vfs.h>
37 #include <linux/inet.h>
38 #include <linux/nfs_xdr.h>
39 #include <linux/slab.h>
40 #include <linux/compat.h>
41 #include <linux/freezer.h>
42 #include <linux/uaccess.h>
43 #include <linux/iversion.h>
44 
45 #include "nfs4_fs.h"
46 #include "callback.h"
47 #include "delegation.h"
48 #include "iostat.h"
49 #include "internal.h"
50 #include "fscache.h"
51 #include "pnfs.h"
52 #include "nfs.h"
53 #include "netns.h"
54 #include "sysfs.h"
55 
56 #include "nfstrace.h"
57 
58 #define NFSDBG_FACILITY		NFSDBG_VFS
59 
60 #define NFS_64_BIT_INODE_NUMBERS_ENABLED	1
61 
62 /* Default is to see 64-bit inode numbers */
63 static bool enable_ino64 = NFS_64_BIT_INODE_NUMBERS_ENABLED;
64 
65 static int nfs_update_inode(struct inode *, struct nfs_fattr *);
66 
67 static struct kmem_cache * nfs_inode_cachep;
68 
69 static inline unsigned long
nfs_fattr_to_ino_t(struct nfs_fattr * fattr)70 nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
71 {
72 	return nfs_fileid_to_ino_t(fattr->fileid);
73 }
74 
nfs_wait_bit_killable(struct wait_bit_key * key,int mode)75 int nfs_wait_bit_killable(struct wait_bit_key *key, int mode)
76 {
77 	if (unlikely(nfs_current_task_exiting()))
78 		return -EINTR;
79 	schedule();
80 	if (signal_pending_state(mode, current))
81 		return -ERESTARTSYS;
82 	return 0;
83 }
84 EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
85 
86 /**
87  * nfs_compat_user_ino64 - returns the user-visible inode number
88  * @fileid: 64-bit fileid
89  *
90  * This function returns a 32-bit inode number if the boot parameter
91  * nfs.enable_ino64 is zero.
92  */
nfs_compat_user_ino64(u64 fileid)93 u64 nfs_compat_user_ino64(u64 fileid)
94 {
95 #ifdef CONFIG_COMPAT
96 	compat_ulong_t ino;
97 #else
98 	unsigned long ino;
99 #endif
100 
101 	if (enable_ino64)
102 		return fileid;
103 	ino = fileid;
104 	if (sizeof(ino) < sizeof(fileid))
105 		ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
106 	return ino;
107 }
108 
nfs_drop_inode(struct inode * inode)109 int nfs_drop_inode(struct inode *inode)
110 {
111 	return NFS_STALE(inode) || inode_generic_drop(inode);
112 }
113 EXPORT_SYMBOL_GPL(nfs_drop_inode);
114 
nfs_clear_inode(struct inode * inode)115 void nfs_clear_inode(struct inode *inode)
116 {
117 	/*
118 	 * The following should never happen...
119 	 */
120 	WARN_ON_ONCE(nfs_have_writebacks(inode));
121 	WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files));
122 	nfs_zap_acl_cache(inode);
123 	nfs_access_zap_cache(inode);
124 	nfs_fscache_clear_inode(inode);
125 }
126 EXPORT_SYMBOL_GPL(nfs_clear_inode);
127 
nfs_evict_inode(struct inode * inode)128 void nfs_evict_inode(struct inode *inode)
129 {
130 	truncate_inode_pages_final(&inode->i_data);
131 	clear_inode(inode);
132 	nfs_clear_inode(inode);
133 }
134 
nfs_sync_inode(struct inode * inode)135 int nfs_sync_inode(struct inode *inode)
136 {
137 	inode_dio_wait(inode);
138 	return nfs_wb_all(inode);
139 }
140 EXPORT_SYMBOL_GPL(nfs_sync_inode);
141 
142 /**
143  * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
144  * @mapping: pointer to struct address_space
145  */
nfs_sync_mapping(struct address_space * mapping)146 int nfs_sync_mapping(struct address_space *mapping)
147 {
148 	int ret = 0;
149 
150 	if (mapping->nrpages != 0) {
151 		unmap_mapping_range(mapping, 0, 0, 0);
152 		ret = nfs_wb_all(mapping->host);
153 	}
154 	return ret;
155 }
156 
nfs_attribute_timeout(struct inode * inode)157 static int nfs_attribute_timeout(struct inode *inode)
158 {
159 	struct nfs_inode *nfsi = NFS_I(inode);
160 
161 	return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
162 }
163 
nfs_check_cache_flags_invalid(struct inode * inode,unsigned long flags)164 static bool nfs_check_cache_flags_invalid(struct inode *inode,
165 					  unsigned long flags)
166 {
167 	unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
168 
169 	return (cache_validity & flags) != 0;
170 }
171 
nfs_check_cache_invalid(struct inode * inode,unsigned long flags)172 bool nfs_check_cache_invalid(struct inode *inode, unsigned long flags)
173 {
174 	if (nfs_check_cache_flags_invalid(inode, flags))
175 		return true;
176 	return nfs_attribute_cache_expired(inode);
177 }
178 EXPORT_SYMBOL_GPL(nfs_check_cache_invalid);
179 
180 #ifdef CONFIG_NFS_V4_2
nfs_has_xattr_cache(const struct nfs_inode * nfsi)181 static bool nfs_has_xattr_cache(const struct nfs_inode *nfsi)
182 {
183 	return nfsi->xattr_cache != NULL;
184 }
185 #else
nfs_has_xattr_cache(const struct nfs_inode * nfsi)186 static bool nfs_has_xattr_cache(const struct nfs_inode *nfsi)
187 {
188 	return false;
189 }
190 #endif
191 
nfs_set_cache_invalid(struct inode * inode,unsigned long flags)192 void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
193 {
194 	struct nfs_inode *nfsi = NFS_I(inode);
195 
196 	if (nfs_have_delegated_attributes(inode)) {
197 		if (!(flags & NFS_INO_REVAL_FORCED))
198 			flags &= ~(NFS_INO_INVALID_MODE |
199 				   NFS_INO_INVALID_OTHER |
200 				   NFS_INO_INVALID_BTIME |
201 				   NFS_INO_INVALID_XATTR);
202 		flags &= ~(NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_SIZE);
203 	}
204 
205 	if (!nfs_has_xattr_cache(nfsi))
206 		flags &= ~NFS_INO_INVALID_XATTR;
207 	if (flags & NFS_INO_INVALID_DATA)
208 		nfs_fscache_invalidate(inode, 0);
209 	flags &= ~NFS_INO_REVAL_FORCED;
210 
211 	flags |= nfsi->cache_validity;
212 	if (inode->i_mapping->nrpages == 0)
213 		flags &= ~NFS_INO_INVALID_DATA;
214 
215 	/* pairs with nfs_clear_invalid_mapping()'s smp_load_acquire() */
216 	smp_store_release(&nfsi->cache_validity, flags);
217 
218 	if (inode->i_mapping->nrpages == 0 ||
219 	    nfsi->cache_validity & NFS_INO_INVALID_DATA) {
220 		nfs_ooo_clear(nfsi);
221 	}
222 	trace_nfs_set_cache_invalid(inode, 0);
223 }
224 EXPORT_SYMBOL_GPL(nfs_set_cache_invalid);
225 
226 /*
227  * Invalidate the local caches
228  */
nfs_zap_caches_locked(struct inode * inode)229 static void nfs_zap_caches_locked(struct inode *inode)
230 {
231 	struct nfs_inode *nfsi = NFS_I(inode);
232 	int mode = inode->i_mode;
233 
234 	nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
235 
236 	nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
237 	nfsi->attrtimeo_timestamp = jiffies;
238 
239 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))
240 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR |
241 						     NFS_INO_INVALID_DATA |
242 						     NFS_INO_INVALID_ACCESS |
243 						     NFS_INO_INVALID_ACL |
244 						     NFS_INO_INVALID_XATTR);
245 	else
246 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR |
247 						     NFS_INO_INVALID_ACCESS |
248 						     NFS_INO_INVALID_ACL |
249 						     NFS_INO_INVALID_XATTR);
250 	nfs_zap_label_cache_locked(nfsi);
251 }
252 
nfs_zap_caches(struct inode * inode)253 void nfs_zap_caches(struct inode *inode)
254 {
255 	spin_lock(&inode->i_lock);
256 	nfs_zap_caches_locked(inode);
257 	spin_unlock(&inode->i_lock);
258 }
259 
nfs_zap_mapping(struct inode * inode,struct address_space * mapping)260 void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
261 {
262 	if (mapping->nrpages != 0) {
263 		spin_lock(&inode->i_lock);
264 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
265 		spin_unlock(&inode->i_lock);
266 	}
267 }
268 
nfs_zap_acl_cache(struct inode * inode)269 void nfs_zap_acl_cache(struct inode *inode)
270 {
271 	void (*clear_acl_cache)(struct inode *);
272 
273 	clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
274 	if (clear_acl_cache != NULL)
275 		clear_acl_cache(inode);
276 	spin_lock(&inode->i_lock);
277 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
278 	spin_unlock(&inode->i_lock);
279 }
280 EXPORT_SYMBOL_GPL(nfs_zap_acl_cache);
281 
nfs_invalidate_atime(struct inode * inode)282 void nfs_invalidate_atime(struct inode *inode)
283 {
284 	if (nfs_have_delegated_atime(inode))
285 		return;
286 	spin_lock(&inode->i_lock);
287 	nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
288 	spin_unlock(&inode->i_lock);
289 }
290 EXPORT_SYMBOL_GPL(nfs_invalidate_atime);
291 
292 /*
293  * Invalidate, but do not unhash, the inode.
294  * NB: must be called with inode->i_lock held!
295  */
nfs_set_inode_stale_locked(struct inode * inode)296 static void nfs_set_inode_stale_locked(struct inode *inode)
297 {
298 	set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
299 	nfs_zap_caches_locked(inode);
300 	trace_nfs_set_inode_stale(inode);
301 }
302 
nfs_set_inode_stale(struct inode * inode)303 void nfs_set_inode_stale(struct inode *inode)
304 {
305 	spin_lock(&inode->i_lock);
306 	nfs_set_inode_stale_locked(inode);
307 	spin_unlock(&inode->i_lock);
308 }
309 
310 struct nfs_find_desc {
311 	struct nfs_fh		*fh;
312 	struct nfs_fattr	*fattr;
313 };
314 
315 /*
316  * In NFSv3 we can have 64bit inode numbers. In order to support
317  * this, and re-exported directories (also seen in NFSv2)
318  * we are forced to allow 2 different inodes to have the same
319  * i_ino.
320  */
321 static int
nfs_find_actor(struct inode * inode,void * opaque)322 nfs_find_actor(struct inode *inode, void *opaque)
323 {
324 	struct nfs_find_desc	*desc = opaque;
325 	struct nfs_fh		*fh = desc->fh;
326 	struct nfs_fattr	*fattr = desc->fattr;
327 
328 	if (NFS_FILEID(inode) != fattr->fileid)
329 		return 0;
330 	if (inode_wrong_type(inode, fattr->mode))
331 		return 0;
332 	if (nfs_compare_fh(NFS_FH(inode), fh))
333 		return 0;
334 	if (is_bad_inode(inode) || NFS_STALE(inode))
335 		return 0;
336 	return 1;
337 }
338 
339 static int
nfs_init_locked(struct inode * inode,void * opaque)340 nfs_init_locked(struct inode *inode, void *opaque)
341 {
342 	struct nfs_find_desc	*desc = opaque;
343 	struct nfs_fattr	*fattr = desc->fattr;
344 
345 	set_nfs_fileid(inode, fattr->fileid);
346 	inode->i_mode = fattr->mode;
347 	nfs_copy_fh(NFS_FH(inode), desc->fh);
348 	return 0;
349 }
350 
351 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
nfs_clear_label_invalid(struct inode * inode)352 static void nfs_clear_label_invalid(struct inode *inode)
353 {
354 	spin_lock(&inode->i_lock);
355 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_LABEL;
356 	spin_unlock(&inode->i_lock);
357 }
358 
nfs_setsecurity(struct inode * inode,struct nfs_fattr * fattr)359 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr)
360 {
361 	int error;
362 
363 	if (fattr->label == NULL)
364 		return;
365 
366 	if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
367 		error = security_inode_notifysecctx(inode, fattr->label->label,
368 				fattr->label->len);
369 		if (error)
370 			printk(KERN_ERR "%s() %s %d "
371 					"security_inode_notifysecctx() %d\n",
372 					__func__,
373 					(char *)fattr->label->label,
374 					fattr->label->len, error);
375 		nfs_clear_label_invalid(inode);
376 	}
377 }
378 
nfs4_label_alloc(struct nfs_server * server,gfp_t flags)379 struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
380 {
381 	struct nfs4_label *label;
382 
383 	if (!(server->caps & NFS_CAP_SECURITY_LABEL))
384 		return NULL;
385 
386 	label = kzalloc(sizeof(struct nfs4_label), flags);
387 	if (label == NULL)
388 		return ERR_PTR(-ENOMEM);
389 
390 	label->label = kzalloc(NFS4_MAXLABELLEN, flags);
391 	if (label->label == NULL) {
392 		kfree(label);
393 		return ERR_PTR(-ENOMEM);
394 	}
395 	label->len = NFS4_MAXLABELLEN;
396 
397 	return label;
398 }
399 EXPORT_SYMBOL_GPL(nfs4_label_alloc);
400 #else
nfs_setsecurity(struct inode * inode,struct nfs_fattr * fattr)401 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr)
402 {
403 }
404 #endif
405 EXPORT_SYMBOL_GPL(nfs_setsecurity);
406 
407 /* Search for inode identified by fh, fileid and i_mode in inode cache. */
408 struct inode *
nfs_ilookup(struct super_block * sb,struct nfs_fattr * fattr,struct nfs_fh * fh)409 nfs_ilookup(struct super_block *sb, struct nfs_fattr *fattr, struct nfs_fh *fh)
410 {
411 	struct nfs_find_desc desc = {
412 		.fh	= fh,
413 		.fattr	= fattr,
414 	};
415 	struct inode *inode;
416 	unsigned long hash;
417 
418 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID) ||
419 	    !(fattr->valid & NFS_ATTR_FATTR_TYPE))
420 		return NULL;
421 
422 	hash = nfs_fattr_to_ino_t(fattr);
423 	inode = ilookup5(sb, hash, nfs_find_actor, &desc);
424 
425 	dprintk("%s: returning %p\n", __func__, inode);
426 	return inode;
427 }
428 
nfs_inode_init_regular(struct nfs_inode * nfsi)429 static void nfs_inode_init_regular(struct nfs_inode *nfsi)
430 {
431 	atomic_long_set(&nfsi->nrequests, 0);
432 	atomic_long_set(&nfsi->redirtied_pages, 0);
433 	INIT_LIST_HEAD(&nfsi->commit_info.list);
434 	atomic_long_set(&nfsi->commit_info.ncommit, 0);
435 	atomic_set(&nfsi->commit_info.rpcs_out, 0);
436 	mutex_init(&nfsi->commit_mutex);
437 }
438 
nfs_inode_init_dir(struct nfs_inode * nfsi)439 static void nfs_inode_init_dir(struct nfs_inode *nfsi)
440 {
441 	nfsi->cache_change_attribute = 0;
442 	memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
443 	init_rwsem(&nfsi->rmdir_sem);
444 }
445 
446 /*
447  * This is our front-end to iget that looks up inodes by file handle
448  * instead of inode number.
449  */
450 struct inode *
nfs_fhget(struct super_block * sb,struct nfs_fh * fh,struct nfs_fattr * fattr)451 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
452 {
453 	struct nfs_find_desc desc = {
454 		.fh	= fh,
455 		.fattr	= fattr
456 	};
457 	struct inode *inode = ERR_PTR(-ENOENT);
458 	u64 fattr_supported = NFS_SB(sb)->fattr_valid;
459 	unsigned long hash;
460 
461 	nfs_attr_check_mountpoint(sb, fattr);
462 
463 	if (nfs_attr_use_mounted_on_fileid(fattr))
464 		fattr->fileid = fattr->mounted_on_fileid;
465 	else if ((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0)
466 		goto out_no_inode;
467 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
468 		goto out_no_inode;
469 
470 	hash = nfs_fattr_to_ino_t(fattr);
471 
472 	inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
473 	if (inode == NULL) {
474 		inode = ERR_PTR(-ENOMEM);
475 		goto out_no_inode;
476 	}
477 
478 	if (inode->i_state & I_NEW) {
479 		struct nfs_inode *nfsi = NFS_I(inode);
480 		unsigned long now = jiffies;
481 
482 		/* We set i_ino for the few things that still rely on it,
483 		 * such as stat(2) */
484 		inode->i_ino = hash;
485 
486 		/* We can't support update_atime(), since the server will reset it */
487 		inode->i_flags |= S_NOATIME|S_NOCMTIME;
488 		inode->i_mode = fattr->mode;
489 		nfsi->cache_validity = 0;
490 		if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
491 				&& (fattr_supported & NFS_ATTR_FATTR_MODE))
492 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MODE);
493 		/* Why so? Because we want revalidate for devices/FIFOs, and
494 		 * that's precisely what we have in nfs_file_inode_operations.
495 		 */
496 		inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
497 		if (S_ISREG(inode->i_mode)) {
498 			inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
499 			inode->i_data.a_ops = &nfs_file_aops;
500 			nfs_inode_init_regular(nfsi);
501 			mapping_set_large_folios(inode->i_mapping);
502 		} else if (S_ISDIR(inode->i_mode)) {
503 			inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
504 			inode->i_fop = &nfs_dir_operations;
505 			inode->i_data.a_ops = &nfs_dir_aops;
506 			nfs_inode_init_dir(nfsi);
507 			/* Deal with crossing mountpoints */
508 			if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
509 					fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
510 				if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
511 					inode->i_op = &nfs_referral_inode_operations;
512 				else
513 					inode->i_op = &nfs_mountpoint_inode_operations;
514 				inode->i_fop = NULL;
515 				inode->i_flags |= S_AUTOMOUNT;
516 			}
517 		} else if (S_ISLNK(inode->i_mode)) {
518 			inode->i_op = &nfs_symlink_inode_operations;
519 			inode_nohighmem(inode);
520 		} else
521 			init_special_inode(inode, inode->i_mode, fattr->rdev);
522 
523 		inode_set_atime(inode, 0, 0);
524 		inode_set_mtime(inode, 0, 0);
525 		inode_set_ctime(inode, 0, 0);
526 		memset(&nfsi->btime, 0, sizeof(nfsi->btime));
527 		inode_set_iversion_raw(inode, 0);
528 		inode->i_size = 0;
529 		clear_nlink(inode);
530 		inode->i_uid = make_kuid(&init_user_ns, -2);
531 		inode->i_gid = make_kgid(&init_user_ns, -2);
532 		inode->i_blocks = 0;
533 		nfsi->write_io = 0;
534 		nfsi->read_io = 0;
535 
536 		nfsi->read_cache_jiffies = fattr->time_start;
537 		nfsi->attr_gencount = fattr->gencount;
538 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
539 			inode_set_atime_to_ts(inode, fattr->atime);
540 		else if (fattr_supported & NFS_ATTR_FATTR_ATIME)
541 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
542 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
543 			inode_set_mtime_to_ts(inode, fattr->mtime);
544 		else if (fattr_supported & NFS_ATTR_FATTR_MTIME)
545 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
546 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
547 			inode_set_ctime_to_ts(inode, fattr->ctime);
548 		else if (fattr_supported & NFS_ATTR_FATTR_CTIME)
549 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CTIME);
550 		if (fattr->valid & NFS_ATTR_FATTR_BTIME)
551 			nfsi->btime = fattr->btime;
552 		else if (fattr_supported & NFS_ATTR_FATTR_BTIME)
553 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_BTIME);
554 		if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
555 			inode_set_iversion_raw(inode, fattr->change_attr);
556 		else
557 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE);
558 		if (fattr->valid & NFS_ATTR_FATTR_SIZE)
559 			inode->i_size = nfs_size_to_loff_t(fattr->size);
560 		else
561 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_SIZE);
562 		if (fattr->valid & NFS_ATTR_FATTR_NLINK)
563 			set_nlink(inode, fattr->nlink);
564 		else if (fattr_supported & NFS_ATTR_FATTR_NLINK)
565 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_NLINK);
566 		else
567 			set_nlink(inode, 1);
568 		if (fattr->valid & NFS_ATTR_FATTR_OWNER)
569 			inode->i_uid = fattr->uid;
570 		else if (fattr_supported & NFS_ATTR_FATTR_OWNER)
571 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
572 		if (fattr->valid & NFS_ATTR_FATTR_GROUP)
573 			inode->i_gid = fattr->gid;
574 		else if (fattr_supported & NFS_ATTR_FATTR_GROUP)
575 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
576 		if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
577 			inode->i_blocks = fattr->du.nfs2.blocks;
578 		else if (fattr_supported & NFS_ATTR_FATTR_BLOCKS_USED &&
579 			 fattr->size != 0)
580 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_BLOCKS);
581 		if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
582 			/*
583 			 * report the blocks in 512byte units
584 			 */
585 			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
586 		} else if (fattr_supported & NFS_ATTR_FATTR_SPACE_USED &&
587 			   fattr->size != 0)
588 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_BLOCKS);
589 
590 		nfs_setsecurity(inode, fattr);
591 
592 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
593 		nfsi->attrtimeo_timestamp = now;
594 		nfsi->access_cache = RB_ROOT;
595 
596 		nfs_fscache_init_inode(inode);
597 
598 		unlock_new_inode(inode);
599 	} else {
600 		int err = nfs_refresh_inode(inode, fattr);
601 		if (err < 0) {
602 			iput(inode);
603 			inode = ERR_PTR(err);
604 			goto out_no_inode;
605 		}
606 	}
607 	dprintk("NFS: nfs_fhget(%s/%Lu fh_crc=0x%08x ct=%d)\n",
608 		inode->i_sb->s_id,
609 		(unsigned long long)NFS_FILEID(inode),
610 		nfs_display_fhandle_hash(fh),
611 		icount_read(inode));
612 
613 out:
614 	return inode;
615 
616 out_no_inode:
617 	dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
618 	goto out;
619 }
620 EXPORT_SYMBOL_GPL(nfs_fhget);
621 
622 static void
nfs_fattr_fixup_delegated(struct inode * inode,struct nfs_fattr * fattr)623 nfs_fattr_fixup_delegated(struct inode *inode, struct nfs_fattr *fattr)
624 {
625 	unsigned long cache_validity = NFS_I(inode)->cache_validity;
626 
627 	if (nfs_have_delegated_mtime(inode)) {
628 		if (!(cache_validity & NFS_INO_INVALID_CTIME))
629 			fattr->valid &= ~(NFS_ATTR_FATTR_PRECTIME |
630 					  NFS_ATTR_FATTR_CTIME);
631 
632 		if (!(cache_validity & NFS_INO_INVALID_MTIME))
633 			fattr->valid &= ~(NFS_ATTR_FATTR_PREMTIME |
634 					  NFS_ATTR_FATTR_MTIME);
635 
636 		if (!(cache_validity & NFS_INO_INVALID_ATIME))
637 			fattr->valid &= ~NFS_ATTR_FATTR_ATIME;
638 	} else if (nfs_have_delegated_atime(inode)) {
639 		if (!(cache_validity & NFS_INO_INVALID_ATIME))
640 			fattr->valid &= ~NFS_ATTR_FATTR_ATIME;
641 	}
642 }
643 
nfs_set_timestamps_to_ts(struct inode * inode,struct iattr * attr)644 static void nfs_set_timestamps_to_ts(struct inode *inode, struct iattr *attr)
645 {
646 	unsigned int cache_flags = 0;
647 
648 	if (attr->ia_valid & ATTR_MTIME_SET) {
649 		struct timespec64 ctime = inode_get_ctime(inode);
650 		struct timespec64 mtime = inode_get_mtime(inode);
651 		struct timespec64 now;
652 		int updated = 0;
653 
654 		now = inode_set_ctime_current(inode);
655 		if (!timespec64_equal(&now, &ctime))
656 			updated |= S_CTIME;
657 
658 		inode_set_mtime_to_ts(inode, attr->ia_mtime);
659 		if (!timespec64_equal(&now, &mtime))
660 			updated |= S_MTIME;
661 
662 		inode_maybe_inc_iversion(inode, updated);
663 		cache_flags |= NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME;
664 	}
665 	if (attr->ia_valid & ATTR_ATIME_SET) {
666 		inode_set_atime_to_ts(inode, attr->ia_atime);
667 		cache_flags |= NFS_INO_INVALID_ATIME;
668 	}
669 	NFS_I(inode)->cache_validity &= ~cache_flags;
670 }
671 
nfs_update_timestamps(struct inode * inode,unsigned int ia_valid)672 static void nfs_update_timestamps(struct inode *inode, unsigned int ia_valid)
673 {
674 	enum file_time_flags time_flags = 0;
675 	unsigned int cache_flags = 0;
676 
677 	if (ia_valid & ATTR_MTIME) {
678 		time_flags |= S_MTIME | S_CTIME;
679 		cache_flags |= NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME;
680 	}
681 	if (ia_valid & ATTR_ATIME) {
682 		time_flags |= S_ATIME;
683 		cache_flags |= NFS_INO_INVALID_ATIME;
684 	}
685 	inode_update_timestamps(inode, time_flags);
686 	NFS_I(inode)->cache_validity &= ~cache_flags;
687 }
688 
nfs_update_delegated_atime(struct inode * inode)689 void nfs_update_delegated_atime(struct inode *inode)
690 {
691 	spin_lock(&inode->i_lock);
692 	if (nfs_have_delegated_atime(inode))
693 		nfs_update_timestamps(inode, ATTR_ATIME);
694 	spin_unlock(&inode->i_lock);
695 }
696 
nfs_update_delegated_mtime_locked(struct inode * inode)697 void nfs_update_delegated_mtime_locked(struct inode *inode)
698 {
699 	if (nfs_have_delegated_mtime(inode))
700 		nfs_update_timestamps(inode, ATTR_MTIME);
701 }
702 
nfs_update_delegated_mtime(struct inode * inode)703 void nfs_update_delegated_mtime(struct inode *inode)
704 {
705 	spin_lock(&inode->i_lock);
706 	nfs_update_delegated_mtime_locked(inode);
707 	spin_unlock(&inode->i_lock);
708 }
709 EXPORT_SYMBOL_GPL(nfs_update_delegated_mtime);
710 
711 #define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
712 
713 int
nfs_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * attr)714 nfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
715 	    struct iattr *attr)
716 {
717 	struct inode *inode = d_inode(dentry);
718 	struct nfs_fattr *fattr;
719 	loff_t oldsize = i_size_read(inode);
720 	int error = 0;
721 	kuid_t task_uid = current_fsuid();
722 	kuid_t owner_uid = inode->i_uid;
723 
724 	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
725 
726 	/* skip mode change if it's just for clearing setuid/setgid */
727 	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
728 		attr->ia_valid &= ~ATTR_MODE;
729 
730 	if (attr->ia_valid & ATTR_SIZE) {
731 		BUG_ON(!S_ISREG(inode->i_mode));
732 
733 		error = inode_newsize_ok(inode, attr->ia_size);
734 		if (error)
735 			return error;
736 
737 		if (attr->ia_size == oldsize)
738 			attr->ia_valid &= ~ATTR_SIZE;
739 	}
740 
741 	if (nfs_have_delegated_mtime(inode) && attr->ia_valid & ATTR_MTIME) {
742 		spin_lock(&inode->i_lock);
743 		if (attr->ia_valid & ATTR_MTIME_SET) {
744 			if (uid_eq(task_uid, owner_uid)) {
745 				nfs_set_timestamps_to_ts(inode, attr);
746 				attr->ia_valid &= ~(ATTR_MTIME|ATTR_MTIME_SET|
747 						ATTR_ATIME|ATTR_ATIME_SET);
748 			}
749 		} else {
750 			nfs_update_timestamps(inode, attr->ia_valid);
751 			attr->ia_valid &= ~(ATTR_MTIME|ATTR_ATIME);
752 		}
753 		spin_unlock(&inode->i_lock);
754 	} else if (nfs_have_delegated_atime(inode) &&
755 		   attr->ia_valid & ATTR_ATIME &&
756 		   !(attr->ia_valid & ATTR_MTIME)) {
757 		if (attr->ia_valid & ATTR_ATIME_SET) {
758 			if (uid_eq(task_uid, owner_uid)) {
759 				spin_lock(&inode->i_lock);
760 				nfs_set_timestamps_to_ts(inode, attr);
761 				spin_unlock(&inode->i_lock);
762 				attr->ia_valid &= ~(ATTR_ATIME|ATTR_ATIME_SET);
763 			}
764 		} else {
765 			nfs_update_delegated_atime(inode);
766 			attr->ia_valid &= ~ATTR_ATIME;
767 		}
768 	}
769 
770 	/* Optimization: if the end result is no change, don't RPC */
771 	if (((attr->ia_valid & NFS_VALID_ATTRS) & ~(ATTR_FILE|ATTR_OPEN)) == 0)
772 		return 0;
773 
774 	trace_nfs_setattr_enter(inode);
775 
776 	/* Write all dirty data */
777 	if (S_ISREG(inode->i_mode)) {
778 		nfs_file_block_o_direct(NFS_I(inode));
779 		nfs_sync_inode(inode);
780 	}
781 
782 	fattr = nfs_alloc_fattr_with_label(NFS_SERVER(inode));
783 	if (fattr == NULL) {
784 		error = -ENOMEM;
785 		goto out;
786 	}
787 
788 	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
789 	if (error == 0) {
790 		if (attr->ia_valid & ATTR_SIZE)
791 			nfs_truncate_last_folio(inode->i_mapping, oldsize,
792 						attr->ia_size);
793 		error = nfs_refresh_inode(inode, fattr);
794 	}
795 	nfs_free_fattr(fattr);
796 out:
797 	trace_nfs_setattr_exit(inode, error);
798 	return error;
799 }
800 EXPORT_SYMBOL_GPL(nfs_setattr);
801 
802 /**
803  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
804  * @inode: inode of the file used
805  * @offset: file offset to start truncating
806  *
807  * This is a copy of the common vmtruncate, but with the locking
808  * corrected to take into account the fact that NFS requires
809  * inode->i_size to be updated under the inode->i_lock.
810  * Note: must be called with inode->i_lock held!
811  */
nfs_vmtruncate(struct inode * inode,loff_t offset)812 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
813 {
814 	int err;
815 
816 	err = inode_newsize_ok(inode, offset);
817 	if (err)
818 		goto out;
819 
820 	trace_nfs_size_truncate(inode, offset);
821 	i_size_write(inode, offset);
822 	/* Optimisation */
823 	if (offset == 0) {
824 		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA;
825 		nfs_ooo_clear(NFS_I(inode));
826 	}
827 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE;
828 
829 	spin_unlock(&inode->i_lock);
830 	truncate_pagecache(inode, offset);
831 	nfs_update_delegated_mtime_locked(inode);
832 	spin_lock(&inode->i_lock);
833 out:
834 	return err;
835 }
836 
837 /**
838  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
839  * @inode: pointer to struct inode
840  * @attr: pointer to struct iattr
841  * @fattr: pointer to struct nfs_fattr
842  *
843  * Note: we do this in the *proc.c in order to ensure that
844  *       it works for things like exclusive creates too.
845  */
nfs_setattr_update_inode(struct inode * inode,struct iattr * attr,struct nfs_fattr * fattr)846 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr,
847 		struct nfs_fattr *fattr)
848 {
849 	/* Barrier: bump the attribute generation count. */
850 	nfs_fattr_set_barrier(fattr);
851 
852 	spin_lock(&inode->i_lock);
853 	NFS_I(inode)->attr_gencount = fattr->gencount;
854 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
855 		if (!nfs_have_delegated_mtime(inode))
856 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
857 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_BLOCKS);
858 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
859 		nfs_vmtruncate(inode, attr->ia_size);
860 	}
861 	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
862 		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_CTIME;
863 		if ((attr->ia_valid & ATTR_KILL_SUID) != 0 &&
864 		    inode->i_mode & S_ISUID)
865 			inode->i_mode &= ~S_ISUID;
866 		if (setattr_should_drop_sgid(&nop_mnt_idmap, inode))
867 			inode->i_mode &= ~S_ISGID;
868 		if ((attr->ia_valid & ATTR_MODE) != 0) {
869 			int mode = attr->ia_mode & S_IALLUGO;
870 			mode |= inode->i_mode & ~S_IALLUGO;
871 			inode->i_mode = mode;
872 		}
873 		if ((attr->ia_valid & ATTR_UID) != 0)
874 			inode->i_uid = attr->ia_uid;
875 		if ((attr->ia_valid & ATTR_GID) != 0)
876 			inode->i_gid = attr->ia_gid;
877 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
878 			inode_set_ctime_to_ts(inode, fattr->ctime);
879 		else
880 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
881 					| NFS_INO_INVALID_CTIME);
882 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS
883 				| NFS_INO_INVALID_ACL);
884 	}
885 	if (attr->ia_valid & (ATTR_ATIME_SET|ATTR_ATIME)) {
886 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_ATIME
887 				| NFS_INO_INVALID_CTIME);
888 		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
889 			inode_set_atime_to_ts(inode, fattr->atime);
890 		else if (attr->ia_valid & ATTR_ATIME_SET)
891 			inode_set_atime_to_ts(inode, attr->ia_atime);
892 		else
893 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
894 
895 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
896 			inode_set_ctime_to_ts(inode, fattr->ctime);
897 		else
898 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
899 					| NFS_INO_INVALID_CTIME);
900 	}
901 	if (attr->ia_valid & (ATTR_MTIME_SET|ATTR_MTIME)) {
902 		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_MTIME
903 				| NFS_INO_INVALID_CTIME);
904 		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
905 			inode_set_mtime_to_ts(inode, fattr->mtime);
906 		else if (attr->ia_valid & ATTR_MTIME_SET)
907 			inode_set_mtime_to_ts(inode, attr->ia_mtime);
908 		else
909 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_MTIME);
910 
911 		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
912 			inode_set_ctime_to_ts(inode, fattr->ctime);
913 		else
914 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE
915 					| NFS_INO_INVALID_CTIME);
916 	}
917 	if (fattr->valid)
918 		nfs_update_inode(inode, fattr);
919 	spin_unlock(&inode->i_lock);
920 }
921 EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
922 
923 /*
924  * Don't request help from readdirplus if the file is being written to,
925  * or if attribute caching is turned off
926  */
nfs_getattr_readdirplus_enable(const struct inode * inode)927 static bool nfs_getattr_readdirplus_enable(const struct inode *inode)
928 {
929 	return nfs_server_capable(inode, NFS_CAP_READDIRPLUS) &&
930 	       !nfs_have_writebacks(inode) && NFS_MAXATTRTIMEO(inode) > 5 * HZ;
931 }
932 
nfs_readdirplus_parent_cache_miss(struct dentry * dentry)933 static void nfs_readdirplus_parent_cache_miss(struct dentry *dentry)
934 {
935 	if (!IS_ROOT(dentry)) {
936 		struct dentry *parent = dget_parent(dentry);
937 		nfs_readdir_record_entry_cache_miss(d_inode(parent));
938 		dput(parent);
939 	}
940 }
941 
nfs_readdirplus_parent_cache_hit(struct dentry * dentry)942 static void nfs_readdirplus_parent_cache_hit(struct dentry *dentry)
943 {
944 	if (!IS_ROOT(dentry)) {
945 		struct dentry *parent = dget_parent(dentry);
946 		nfs_readdir_record_entry_cache_hit(d_inode(parent));
947 		dput(parent);
948 	}
949 }
950 
nfs_get_valid_attrmask(struct inode * inode)951 static u32 nfs_get_valid_attrmask(struct inode *inode)
952 {
953 	u64 fattr_valid = NFS_SERVER(inode)->fattr_valid;
954 	unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
955 	u32 reply_mask = STATX_INO | STATX_TYPE;
956 
957 	if (!(cache_validity & NFS_INO_INVALID_ATIME))
958 		reply_mask |= STATX_ATIME;
959 	if (!(cache_validity & NFS_INO_INVALID_CTIME))
960 		reply_mask |= STATX_CTIME;
961 	if (!(cache_validity & NFS_INO_INVALID_MTIME))
962 		reply_mask |= STATX_MTIME;
963 	if (!(cache_validity & NFS_INO_INVALID_SIZE))
964 		reply_mask |= STATX_SIZE;
965 	if (!(cache_validity & NFS_INO_INVALID_NLINK))
966 		reply_mask |= STATX_NLINK;
967 	if (!(cache_validity & NFS_INO_INVALID_MODE))
968 		reply_mask |= STATX_MODE;
969 	if (!(cache_validity & NFS_INO_INVALID_OTHER))
970 		reply_mask |= STATX_UID | STATX_GID;
971 	if (!(cache_validity & NFS_INO_INVALID_BLOCKS))
972 		reply_mask |= STATX_BLOCKS;
973 	if (!(cache_validity & NFS_INO_INVALID_BTIME) &&
974 	    (fattr_valid & NFS_ATTR_FATTR_BTIME))
975 		reply_mask |= STATX_BTIME;
976 	if (!(cache_validity & NFS_INO_INVALID_CHANGE))
977 		reply_mask |= STATX_CHANGE_COOKIE;
978 	return reply_mask;
979 }
980 
nfs_getattr(struct mnt_idmap * idmap,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)981 int nfs_getattr(struct mnt_idmap *idmap, const struct path *path,
982 		struct kstat *stat, u32 request_mask, unsigned int query_flags)
983 {
984 	struct inode *inode = d_inode(path->dentry);
985 	struct nfs_server *server = NFS_SERVER(inode);
986 	u64 fattr_valid = server->fattr_valid;
987 	unsigned long cache_validity;
988 	int err = 0;
989 	bool force_sync = query_flags & AT_STATX_FORCE_SYNC;
990 	bool do_update = false;
991 	bool readdirplus_enabled = nfs_getattr_readdirplus_enable(inode);
992 
993 	trace_nfs_getattr_enter(inode);
994 
995 	request_mask &= STATX_TYPE | STATX_MODE | STATX_NLINK | STATX_UID |
996 			STATX_GID | STATX_ATIME | STATX_MTIME | STATX_CTIME |
997 			STATX_INO | STATX_SIZE | STATX_BLOCKS | STATX_BTIME |
998 			STATX_CHANGE_COOKIE;
999 
1000 	if (!(fattr_valid & NFS_ATTR_FATTR_BTIME))
1001 		request_mask &= ~STATX_BTIME;
1002 
1003 	if ((query_flags & AT_STATX_DONT_SYNC) && !force_sync) {
1004 		if (readdirplus_enabled)
1005 			nfs_readdirplus_parent_cache_hit(path->dentry);
1006 		goto out_no_revalidate;
1007 	}
1008 
1009 	/* Flush out writes to the server in order to update c/mtime/version.  */
1010 	if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_CHANGE_COOKIE)) &&
1011 	    S_ISREG(inode->i_mode)) {
1012 		if (nfs_have_delegated_mtime(inode))
1013 			filemap_fdatawrite(inode->i_mapping);
1014 		else
1015 			filemap_write_and_wait(inode->i_mapping);
1016 	}
1017 
1018 	/*
1019 	 * We may force a getattr if the user cares about atime.
1020 	 *
1021 	 * Note that we only have to check the vfsmount flags here:
1022 	 *  - NFS always sets S_NOATIME by so checking it would give a
1023 	 *    bogus result
1024 	 *  - NFS never sets SB_NOATIME or SB_NODIRATIME so there is
1025 	 *    no point in checking those.
1026 	 */
1027 	if ((path->mnt->mnt_flags & MNT_NOATIME) ||
1028 	    ((path->mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
1029 		request_mask &= ~STATX_ATIME;
1030 
1031 	/* Is the user requesting attributes that might need revalidation? */
1032 	if (!(request_mask & (STATX_MODE|STATX_NLINK|STATX_ATIME|STATX_CTIME|
1033 					STATX_MTIME|STATX_UID|STATX_GID|
1034 					STATX_SIZE|STATX_BLOCKS|STATX_BTIME|
1035 					STATX_CHANGE_COOKIE)))
1036 		goto out_no_revalidate;
1037 
1038 	/* Check whether the cached attributes are stale */
1039 	do_update |= force_sync || nfs_attribute_cache_expired(inode);
1040 	cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
1041 	do_update |= cache_validity & NFS_INO_INVALID_CHANGE;
1042 	if (request_mask & STATX_ATIME)
1043 		do_update |= cache_validity & NFS_INO_INVALID_ATIME;
1044 	if (request_mask & STATX_CTIME)
1045 		do_update |= cache_validity & NFS_INO_INVALID_CTIME;
1046 	if (request_mask & STATX_MTIME)
1047 		do_update |= cache_validity & NFS_INO_INVALID_MTIME;
1048 	if (request_mask & STATX_SIZE)
1049 		do_update |= cache_validity & NFS_INO_INVALID_SIZE;
1050 	if (request_mask & STATX_NLINK)
1051 		do_update |= cache_validity & NFS_INO_INVALID_NLINK;
1052 	if (request_mask & STATX_MODE)
1053 		do_update |= cache_validity & NFS_INO_INVALID_MODE;
1054 	if (request_mask & (STATX_UID | STATX_GID))
1055 		do_update |= cache_validity & NFS_INO_INVALID_OTHER;
1056 	if (request_mask & STATX_BLOCKS)
1057 		do_update |= cache_validity & NFS_INO_INVALID_BLOCKS;
1058 	if (request_mask & STATX_BTIME)
1059 		do_update |= cache_validity & NFS_INO_INVALID_BTIME;
1060 
1061 	if (do_update) {
1062 		if (readdirplus_enabled)
1063 			nfs_readdirplus_parent_cache_miss(path->dentry);
1064 		err = __nfs_revalidate_inode(server, inode);
1065 		if (err)
1066 			goto out;
1067 	} else if (readdirplus_enabled)
1068 		nfs_readdirplus_parent_cache_hit(path->dentry);
1069 out_no_revalidate:
1070 	/* Only return attributes that were revalidated. */
1071 	stat->result_mask = nfs_get_valid_attrmask(inode) | request_mask;
1072 
1073 	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
1074 	stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
1075 	stat->change_cookie = inode_peek_iversion_raw(inode);
1076 	stat->attributes_mask |= STATX_ATTR_CHANGE_MONOTONIC;
1077 	if (server->change_attr_type != NFS4_CHANGE_TYPE_IS_UNDEFINED)
1078 		stat->attributes |= STATX_ATTR_CHANGE_MONOTONIC;
1079 	if (S_ISDIR(inode->i_mode))
1080 		stat->blksize = NFS_SERVER(inode)->dtsize;
1081 	stat->btime = NFS_I(inode)->btime;
1082 
1083 	/* Special handling for STATX_DIOALIGN and STATX_DIO_READ_ALIGN
1084 	 * - NFS doesn't have DIO alignment constraints, avoid getting
1085 	 *   these DIO attrs from remote and just respond with most
1086 	 *   accommodating limits (so client will issue supported DIO).
1087 	 * - this is unintuitive, but the most coarse-grained
1088 	 *   dio_offset_align is the most accommodating.
1089 	 */
1090 	if ((request_mask & (STATX_DIOALIGN | STATX_DIO_READ_ALIGN)) &&
1091 	    S_ISREG(inode->i_mode)) {
1092 		stat->result_mask |= STATX_DIOALIGN | STATX_DIO_READ_ALIGN;
1093 		stat->dio_mem_align = 4; /* 4-byte alignment */
1094 		stat->dio_offset_align = PAGE_SIZE;
1095 		stat->dio_read_offset_align = stat->dio_offset_align;
1096 	}
1097 out:
1098 	trace_nfs_getattr_exit(inode, err);
1099 	return err;
1100 }
1101 EXPORT_SYMBOL_GPL(nfs_getattr);
1102 
nfs_init_lock_context(struct nfs_lock_context * l_ctx)1103 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
1104 {
1105 	refcount_set(&l_ctx->count, 1);
1106 	l_ctx->lockowner = current->files;
1107 	INIT_LIST_HEAD(&l_ctx->list);
1108 	atomic_set(&l_ctx->io_count, 0);
1109 }
1110 
__nfs_find_lock_context(struct nfs_open_context * ctx)1111 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
1112 {
1113 	struct nfs_lock_context *pos;
1114 
1115 	list_for_each_entry_rcu(pos, &ctx->lock_context.list, list) {
1116 		if (pos->lockowner != current->files)
1117 			continue;
1118 		if (refcount_inc_not_zero(&pos->count))
1119 			return pos;
1120 	}
1121 	return NULL;
1122 }
1123 
nfs_get_lock_context(struct nfs_open_context * ctx)1124 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
1125 {
1126 	struct nfs_lock_context *res, *new = NULL;
1127 	struct inode *inode = d_inode(ctx->dentry);
1128 
1129 	rcu_read_lock();
1130 	res = __nfs_find_lock_context(ctx);
1131 	rcu_read_unlock();
1132 	if (res == NULL) {
1133 		new = kmalloc(sizeof(*new), GFP_KERNEL_ACCOUNT);
1134 		if (new == NULL)
1135 			return ERR_PTR(-ENOMEM);
1136 		nfs_init_lock_context(new);
1137 		spin_lock(&inode->i_lock);
1138 		res = __nfs_find_lock_context(ctx);
1139 		if (res == NULL) {
1140 			new->open_context = get_nfs_open_context(ctx);
1141 			if (new->open_context) {
1142 				list_add_tail_rcu(&new->list,
1143 						&ctx->lock_context.list);
1144 				res = new;
1145 				new = NULL;
1146 			} else
1147 				res = ERR_PTR(-EBADF);
1148 		}
1149 		spin_unlock(&inode->i_lock);
1150 		kfree(new);
1151 	}
1152 	return res;
1153 }
1154 EXPORT_SYMBOL_GPL(nfs_get_lock_context);
1155 
nfs_put_lock_context(struct nfs_lock_context * l_ctx)1156 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
1157 {
1158 	struct nfs_open_context *ctx = l_ctx->open_context;
1159 	struct inode *inode = d_inode(ctx->dentry);
1160 
1161 	if (!refcount_dec_and_lock(&l_ctx->count, &inode->i_lock))
1162 		return;
1163 	list_del_rcu(&l_ctx->list);
1164 	spin_unlock(&inode->i_lock);
1165 	put_nfs_open_context(ctx);
1166 	kfree_rcu(l_ctx, rcu_head);
1167 }
1168 EXPORT_SYMBOL_GPL(nfs_put_lock_context);
1169 
1170 /**
1171  * nfs_close_context - Common close_context() routine NFSv2/v3
1172  * @ctx: pointer to context
1173  * @is_sync: is this a synchronous close
1174  *
1175  * Ensure that the attributes are up to date if we're mounted
1176  * with close-to-open semantics and we have cached data that will
1177  * need to be revalidated on open.
1178  */
nfs_close_context(struct nfs_open_context * ctx,int is_sync)1179 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
1180 {
1181 	struct nfs_inode *nfsi;
1182 	struct inode *inode;
1183 
1184 	if (!(ctx->mode & FMODE_WRITE))
1185 		return;
1186 	if (!is_sync)
1187 		return;
1188 	inode = d_inode(ctx->dentry);
1189 	if (nfs_have_read_or_write_delegation(inode))
1190 		return;
1191 	nfsi = NFS_I(inode);
1192 	if (inode->i_mapping->nrpages == 0)
1193 		return;
1194 	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1195 		return;
1196 	if (!list_empty(&nfsi->open_files))
1197 		return;
1198 	if (NFS_SERVER(inode)->flags & NFS_MOUNT_NOCTO)
1199 		return;
1200 	nfs_revalidate_inode(inode,
1201 			     NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_SIZE);
1202 }
1203 EXPORT_SYMBOL_GPL(nfs_close_context);
1204 
alloc_nfs_open_context(struct dentry * dentry,fmode_t f_mode,struct file * filp)1205 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry,
1206 						fmode_t f_mode,
1207 						struct file *filp)
1208 {
1209 	struct nfs_open_context *ctx;
1210 
1211 	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL_ACCOUNT);
1212 	if (!ctx)
1213 		return ERR_PTR(-ENOMEM);
1214 	nfs_sb_active(dentry->d_sb);
1215 	ctx->dentry = dget(dentry);
1216 	if (filp)
1217 		ctx->cred = get_cred(filp->f_cred);
1218 	else
1219 		ctx->cred = get_current_cred();
1220 	rcu_assign_pointer(ctx->ll_cred, NULL);
1221 	ctx->state = NULL;
1222 	ctx->mode = f_mode;
1223 	ctx->flags = 0;
1224 	ctx->error = 0;
1225 	ctx->flock_owner = (fl_owner_t)filp;
1226 	nfs_init_lock_context(&ctx->lock_context);
1227 	ctx->lock_context.open_context = ctx;
1228 	INIT_LIST_HEAD(&ctx->list);
1229 	ctx->mdsthreshold = NULL;
1230 	nfs_localio_file_init(&ctx->nfl);
1231 
1232 	return ctx;
1233 }
1234 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
1235 
get_nfs_open_context(struct nfs_open_context * ctx)1236 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
1237 {
1238 	if (ctx != NULL && refcount_inc_not_zero(&ctx->lock_context.count))
1239 		return ctx;
1240 	return NULL;
1241 }
1242 EXPORT_SYMBOL_GPL(get_nfs_open_context);
1243 
__put_nfs_open_context(struct nfs_open_context * ctx,int is_sync)1244 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
1245 {
1246 	struct inode *inode = d_inode(ctx->dentry);
1247 	struct super_block *sb = ctx->dentry->d_sb;
1248 
1249 	if (!refcount_dec_and_test(&ctx->lock_context.count))
1250 		return;
1251 	if (!list_empty(&ctx->list)) {
1252 		spin_lock(&inode->i_lock);
1253 		list_del_rcu(&ctx->list);
1254 		spin_unlock(&inode->i_lock);
1255 	}
1256 	if (inode != NULL)
1257 		NFS_PROTO(inode)->close_context(ctx, is_sync);
1258 	put_cred(ctx->cred);
1259 	dput(ctx->dentry);
1260 	nfs_sb_deactive(sb);
1261 	put_rpccred(rcu_dereference_protected(ctx->ll_cred, 1));
1262 	kfree(ctx->mdsthreshold);
1263 	nfs_close_local_fh(&ctx->nfl);
1264 	kfree_rcu(ctx, rcu_head);
1265 }
1266 
put_nfs_open_context(struct nfs_open_context * ctx)1267 void put_nfs_open_context(struct nfs_open_context *ctx)
1268 {
1269 	__put_nfs_open_context(ctx, 0);
1270 }
1271 EXPORT_SYMBOL_GPL(put_nfs_open_context);
1272 
put_nfs_open_context_sync(struct nfs_open_context * ctx)1273 static void put_nfs_open_context_sync(struct nfs_open_context *ctx)
1274 {
1275 	__put_nfs_open_context(ctx, 1);
1276 }
1277 
1278 /*
1279  * Ensure that mmap has a recent RPC credential for use when writing out
1280  * shared pages
1281  */
nfs_inode_attach_open_context(struct nfs_open_context * ctx)1282 void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
1283 {
1284 	struct inode *inode = d_inode(ctx->dentry);
1285 	struct nfs_inode *nfsi = NFS_I(inode);
1286 
1287 	spin_lock(&inode->i_lock);
1288 	if (list_empty(&nfsi->open_files) &&
1289 	    nfs_ooo_test(nfsi))
1290 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA |
1291 						     NFS_INO_REVAL_FORCED);
1292 	list_add_tail_rcu(&ctx->list, &nfsi->open_files);
1293 	spin_unlock(&inode->i_lock);
1294 }
1295 EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
1296 
nfs_file_set_open_context(struct file * filp,struct nfs_open_context * ctx)1297 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
1298 {
1299 	filp->private_data = get_nfs_open_context(ctx);
1300 	set_bit(NFS_CONTEXT_FILE_OPEN, &ctx->flags);
1301 	if (list_empty(&ctx->list))
1302 		nfs_inode_attach_open_context(ctx);
1303 }
1304 EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
1305 
1306 /*
1307  * Given an inode, search for an open context with the desired characteristics
1308  */
nfs_find_open_context(struct inode * inode,const struct cred * cred,fmode_t mode)1309 struct nfs_open_context *nfs_find_open_context(struct inode *inode, const struct cred *cred, fmode_t mode)
1310 {
1311 	struct nfs_inode *nfsi = NFS_I(inode);
1312 	struct nfs_open_context *pos, *ctx = NULL;
1313 
1314 	rcu_read_lock();
1315 	list_for_each_entry_rcu(pos, &nfsi->open_files, list) {
1316 		if (cred != NULL && cred_fscmp(pos->cred, cred) != 0)
1317 			continue;
1318 		if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
1319 			continue;
1320 		if (!test_bit(NFS_CONTEXT_FILE_OPEN, &pos->flags))
1321 			continue;
1322 		ctx = get_nfs_open_context(pos);
1323 		if (ctx)
1324 			break;
1325 	}
1326 	rcu_read_unlock();
1327 	return ctx;
1328 }
1329 
nfs_file_clear_open_context(struct file * filp)1330 void nfs_file_clear_open_context(struct file *filp)
1331 {
1332 	struct nfs_open_context *ctx = nfs_file_open_context(filp);
1333 
1334 	if (ctx) {
1335 		struct inode *inode = d_inode(ctx->dentry);
1336 
1337 		clear_bit(NFS_CONTEXT_FILE_OPEN, &ctx->flags);
1338 		/*
1339 		 * We fatal error on write before. Try to writeback
1340 		 * every page again.
1341 		 */
1342 		if (ctx->error < 0)
1343 			invalidate_inode_pages2(inode->i_mapping);
1344 		filp->private_data = NULL;
1345 		put_nfs_open_context_sync(ctx);
1346 	}
1347 }
1348 
1349 /*
1350  * These allocate and release file read/write context information.
1351  */
nfs_open(struct inode * inode,struct file * filp)1352 int nfs_open(struct inode *inode, struct file *filp)
1353 {
1354 	struct nfs_open_context *ctx;
1355 
1356 	ctx = alloc_nfs_open_context(file_dentry(filp),
1357 				     flags_to_mode(filp->f_flags), filp);
1358 	if (IS_ERR(ctx))
1359 		return PTR_ERR(ctx);
1360 	nfs_file_set_open_context(filp, ctx);
1361 	put_nfs_open_context(ctx);
1362 	nfs_fscache_open_file(inode, filp);
1363 	return 0;
1364 }
1365 
1366 /*
1367  * This function is called whenever some part of NFS notices that
1368  * the cached attributes have to be refreshed.
1369  */
1370 int
__nfs_revalidate_inode(struct nfs_server * server,struct inode * inode)1371 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1372 {
1373 	int		 status = -ESTALE;
1374 	struct nfs_fattr *fattr = NULL;
1375 	struct nfs_inode *nfsi = NFS_I(inode);
1376 
1377 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Lu)\n",
1378 		inode->i_sb->s_id, (unsigned long long)NFS_FILEID(inode));
1379 
1380 	trace_nfs_revalidate_inode_enter(inode);
1381 
1382 	if (is_bad_inode(inode))
1383 		goto out;
1384 	if (NFS_STALE(inode))
1385 		goto out;
1386 
1387 	/* pNFS: Attributes aren't updated until we layoutcommit */
1388 	if (S_ISREG(inode->i_mode)) {
1389 		status = pnfs_sync_inode(inode, false);
1390 		if (status)
1391 			goto out;
1392 	}
1393 
1394 	status = -ENOMEM;
1395 	fattr = nfs_alloc_fattr_with_label(NFS_SERVER(inode));
1396 	if (fattr == NULL)
1397 		goto out;
1398 
1399 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
1400 
1401 	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr, inode);
1402 	if (status != 0) {
1403 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) getattr failed, error=%d\n",
1404 			 inode->i_sb->s_id,
1405 			 (unsigned long long)NFS_FILEID(inode), status);
1406 		switch (status) {
1407 		case -ETIMEDOUT:
1408 			/* A soft timeout occurred. Use cached information? */
1409 			if (server->flags & NFS_MOUNT_SOFTREVAL)
1410 				status = 0;
1411 			break;
1412 		case -ESTALE:
1413 			if (!S_ISDIR(inode->i_mode))
1414 				nfs_set_inode_stale(inode);
1415 			else
1416 				nfs_zap_caches(inode);
1417 		}
1418 		goto out;
1419 	}
1420 
1421 	status = nfs_refresh_inode(inode, fattr);
1422 	if (status) {
1423 		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) refresh failed, error=%d\n",
1424 			 inode->i_sb->s_id,
1425 			 (unsigned long long)NFS_FILEID(inode), status);
1426 		goto out;
1427 	}
1428 
1429 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
1430 		nfs_zap_acl_cache(inode);
1431 
1432 	nfs_setsecurity(inode, fattr);
1433 
1434 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) revalidation complete\n",
1435 		inode->i_sb->s_id,
1436 		(unsigned long long)NFS_FILEID(inode));
1437 
1438 out:
1439 	nfs_free_fattr(fattr);
1440 	trace_nfs_revalidate_inode_exit(inode, status);
1441 	return status;
1442 }
1443 
nfs_attribute_cache_expired(struct inode * inode)1444 int nfs_attribute_cache_expired(struct inode *inode)
1445 {
1446 	if (nfs_have_delegated_attributes(inode))
1447 		return 0;
1448 	return nfs_attribute_timeout(inode);
1449 }
1450 
1451 /**
1452  * nfs_revalidate_inode - Revalidate the inode attributes
1453  * @inode: pointer to inode struct
1454  * @flags: cache flags to check
1455  *
1456  * Updates inode attribute information by retrieving the data from the server.
1457  */
nfs_revalidate_inode(struct inode * inode,unsigned long flags)1458 int nfs_revalidate_inode(struct inode *inode, unsigned long flags)
1459 {
1460 	if (!nfs_check_cache_invalid(inode, flags))
1461 		return NFS_STALE(inode) ? -ESTALE : 0;
1462 	return __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1463 }
1464 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
1465 
nfs_invalidate_mapping(struct inode * inode,struct address_space * mapping)1466 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
1467 {
1468 	int ret;
1469 
1470 	nfs_fscache_invalidate(inode, 0);
1471 	if (mapping->nrpages != 0) {
1472 		if (S_ISREG(inode->i_mode)) {
1473 			ret = nfs_sync_mapping(mapping);
1474 			if (ret < 0)
1475 				return ret;
1476 		}
1477 		ret = invalidate_inode_pages2(mapping);
1478 		if (ret < 0)
1479 			return ret;
1480 	}
1481 	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
1482 
1483 	dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
1484 			inode->i_sb->s_id,
1485 			(unsigned long long)NFS_FILEID(inode));
1486 	return 0;
1487 }
1488 
1489 /**
1490  * nfs_clear_invalid_mapping - Conditionally clear a mapping
1491  * @mapping: pointer to mapping
1492  *
1493  * If the NFS_INO_INVALID_DATA inode flag is set, clear the mapping.
1494  */
nfs_clear_invalid_mapping(struct address_space * mapping)1495 int nfs_clear_invalid_mapping(struct address_space *mapping)
1496 {
1497 	struct inode *inode = mapping->host;
1498 	struct nfs_inode *nfsi = NFS_I(inode);
1499 	unsigned long *bitlock = &nfsi->flags;
1500 	int ret = 0;
1501 
1502 	/*
1503 	 * We must clear NFS_INO_INVALID_DATA first to ensure that
1504 	 * invalidations that come in while we're shooting down the mappings
1505 	 * are respected. But, that leaves a race window where one revalidator
1506 	 * can clear the flag, and then another checks it before the mapping
1507 	 * gets invalidated. Fix that by serializing access to this part of
1508 	 * the function.
1509 	 *
1510 	 * At the same time, we need to allow other tasks to see whether we
1511 	 * might be in the middle of invalidating the pages, so we only set
1512 	 * the bit lock here if it looks like we're going to be doing that.
1513 	 */
1514 	for (;;) {
1515 		ret = wait_on_bit_action(bitlock, NFS_INO_INVALIDATING,
1516 					 nfs_wait_bit_killable,
1517 					 TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
1518 		if (ret)
1519 			goto out;
1520 		smp_rmb(); /* pairs with smp_wmb() below */
1521 		if (test_bit(NFS_INO_INVALIDATING, bitlock))
1522 			continue;
1523 		/* pairs with nfs_set_cache_invalid()'s smp_store_release() */
1524 		if (!(smp_load_acquire(&nfsi->cache_validity) & NFS_INO_INVALID_DATA))
1525 			goto out;
1526 		/* Slow-path that double-checks with spinlock held */
1527 		spin_lock(&inode->i_lock);
1528 		if (test_bit(NFS_INO_INVALIDATING, bitlock)) {
1529 			spin_unlock(&inode->i_lock);
1530 			continue;
1531 		}
1532 		if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1533 			break;
1534 		spin_unlock(&inode->i_lock);
1535 		goto out;
1536 	}
1537 
1538 	set_bit(NFS_INO_INVALIDATING, bitlock);
1539 	smp_wmb();
1540 	nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
1541 	nfs_ooo_clear(nfsi);
1542 	spin_unlock(&inode->i_lock);
1543 	trace_nfs_invalidate_mapping_enter(inode);
1544 	ret = nfs_invalidate_mapping(inode, mapping);
1545 	trace_nfs_invalidate_mapping_exit(inode, ret);
1546 
1547 	clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
1548 	smp_mb__after_atomic();
1549 	wake_up_bit(bitlock, NFS_INO_INVALIDATING);
1550 out:
1551 	return ret;
1552 }
1553 
nfs_mapping_need_revalidate_inode(struct inode * inode)1554 bool nfs_mapping_need_revalidate_inode(struct inode *inode)
1555 {
1556 	return nfs_check_cache_invalid(inode, NFS_INO_INVALID_CHANGE) ||
1557 		NFS_STALE(inode);
1558 }
1559 
nfs_revalidate_mapping_rcu(struct inode * inode)1560 int nfs_revalidate_mapping_rcu(struct inode *inode)
1561 {
1562 	struct nfs_inode *nfsi = NFS_I(inode);
1563 	unsigned long *bitlock = &nfsi->flags;
1564 	int ret = 0;
1565 
1566 	if (IS_SWAPFILE(inode))
1567 		goto out;
1568 	if (nfs_mapping_need_revalidate_inode(inode)) {
1569 		ret = -ECHILD;
1570 		goto out;
1571 	}
1572 	spin_lock(&inode->i_lock);
1573 	if (test_bit(NFS_INO_INVALIDATING, bitlock) ||
1574 	    (nfsi->cache_validity & NFS_INO_INVALID_DATA))
1575 		ret = -ECHILD;
1576 	spin_unlock(&inode->i_lock);
1577 out:
1578 	return ret;
1579 }
1580 
1581 /**
1582  * nfs_revalidate_mapping - Revalidate the pagecache
1583  * @inode: pointer to host inode
1584  * @mapping: pointer to mapping
1585  */
nfs_revalidate_mapping(struct inode * inode,struct address_space * mapping)1586 int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
1587 {
1588 	/* swapfiles are not supposed to be shared. */
1589 	if (IS_SWAPFILE(inode))
1590 		return 0;
1591 
1592 	if (nfs_mapping_need_revalidate_inode(inode)) {
1593 		int ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1594 		if (ret < 0)
1595 			return ret;
1596 	}
1597 
1598 	return nfs_clear_invalid_mapping(mapping);
1599 }
1600 
nfs_file_has_writers(struct nfs_inode * nfsi)1601 static bool nfs_file_has_writers(struct nfs_inode *nfsi)
1602 {
1603 	struct inode *inode = &nfsi->vfs_inode;
1604 
1605 	if (!S_ISREG(inode->i_mode))
1606 		return false;
1607 	if (list_empty(&nfsi->open_files))
1608 		return false;
1609 	return inode_is_open_for_write(inode);
1610 }
1611 
nfs_file_has_buffered_writers(struct nfs_inode * nfsi)1612 static bool nfs_file_has_buffered_writers(struct nfs_inode *nfsi)
1613 {
1614 	return nfs_file_has_writers(nfsi) && nfs_file_io_is_buffered(nfsi);
1615 }
1616 
nfs_wcc_update_inode(struct inode * inode,struct nfs_fattr * fattr)1617 static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1618 {
1619 	struct timespec64 ts;
1620 
1621 	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
1622 			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
1623 			&& inode_eq_iversion_raw(inode, fattr->pre_change_attr)) {
1624 		inode_set_iversion_raw(inode, fattr->change_attr);
1625 		if (S_ISDIR(inode->i_mode))
1626 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1627 		else if (nfs_server_capable(inode, NFS_CAP_XATTR))
1628 			nfs_set_cache_invalid(inode, NFS_INO_INVALID_XATTR);
1629 	}
1630 	/* If we have atomic WCC data, we may update some attributes */
1631 	ts = inode_get_ctime(inode);
1632 	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
1633 			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
1634 			&& timespec64_equal(&ts, &fattr->pre_ctime)) {
1635 		inode_set_ctime_to_ts(inode, fattr->ctime);
1636 	}
1637 
1638 	ts = inode_get_mtime(inode);
1639 	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
1640 			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
1641 			&& timespec64_equal(&ts, &fattr->pre_mtime)) {
1642 		inode_set_mtime_to_ts(inode, fattr->mtime);
1643 	}
1644 	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
1645 			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
1646 			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
1647 			&& !nfs_have_writebacks(inode)) {
1648 		trace_nfs_size_wcc(inode, fattr->size);
1649 		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
1650 	}
1651 }
1652 
1653 /**
1654  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1655  * @inode: pointer to inode
1656  * @fattr: updated attributes
1657  *
1658  * Verifies the attribute cache. If we have just changed the attributes,
1659  * so that fattr carries weak cache consistency data, then it may
1660  * also update the ctime/mtime/change_attribute.
1661  */
nfs_check_inode_attributes(struct inode * inode,struct nfs_fattr * fattr)1662 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1663 {
1664 	struct nfs_inode *nfsi = NFS_I(inode);
1665 	loff_t cur_size, new_isize;
1666 	unsigned long invalid = 0;
1667 	struct timespec64 ts;
1668 
1669 	if (nfs_have_delegated_attributes(inode))
1670 		return 0;
1671 
1672 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
1673 		/* Only a mounted-on-fileid? Just exit */
1674 		if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
1675 			return 0;
1676 	/* Has the inode gone and changed behind our back? */
1677 	} else if (nfsi->fileid != fattr->fileid) {
1678 		/* Is this perhaps the mounted-on fileid? */
1679 		if ((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) &&
1680 		    nfsi->fileid == fattr->mounted_on_fileid)
1681 			return 0;
1682 		return -ESTALE;
1683 	}
1684 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && inode_wrong_type(inode, fattr->mode))
1685 		return -ESTALE;
1686 
1687 
1688 	if (!nfs_file_has_buffered_writers(nfsi)) {
1689 		/* Verify a few of the more important attributes */
1690 		if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 && !inode_eq_iversion_raw(inode, fattr->change_attr))
1691 			invalid |= NFS_INO_INVALID_CHANGE;
1692 
1693 		ts = inode_get_mtime(inode);
1694 		if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec64_equal(&ts, &fattr->mtime))
1695 			invalid |= NFS_INO_INVALID_MTIME;
1696 
1697 		ts = inode_get_ctime(inode);
1698 		if ((fattr->valid & NFS_ATTR_FATTR_CTIME) && !timespec64_equal(&ts, &fattr->ctime))
1699 			invalid |= NFS_INO_INVALID_CTIME;
1700 
1701 		if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1702 			cur_size = i_size_read(inode);
1703 			new_isize = nfs_size_to_loff_t(fattr->size);
1704 			if (cur_size != new_isize)
1705 				invalid |= NFS_INO_INVALID_SIZE;
1706 		}
1707 	}
1708 
1709 	/* Have any file permissions changed? */
1710 	if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
1711 		invalid |= NFS_INO_INVALID_MODE;
1712 	if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && !uid_eq(inode->i_uid, fattr->uid))
1713 		invalid |= NFS_INO_INVALID_OTHER;
1714 	if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && !gid_eq(inode->i_gid, fattr->gid))
1715 		invalid |= NFS_INO_INVALID_OTHER;
1716 
1717 	/* Has the link count changed? */
1718 	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
1719 		invalid |= NFS_INO_INVALID_NLINK;
1720 
1721 	ts = inode_get_atime(inode);
1722 	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec64_equal(&ts, &fattr->atime))
1723 		invalid |= NFS_INO_INVALID_ATIME;
1724 
1725 	if (invalid != 0)
1726 		nfs_set_cache_invalid(inode, invalid);
1727 
1728 	nfsi->read_cache_jiffies = fattr->time_start;
1729 	return 0;
1730 }
1731 
1732 static atomic_long_t nfs_attr_generation_counter;
1733 
nfs_read_attr_generation_counter(void)1734 static unsigned long nfs_read_attr_generation_counter(void)
1735 {
1736 	return atomic_long_read(&nfs_attr_generation_counter);
1737 }
1738 
nfs_inc_attr_generation_counter(void)1739 unsigned long nfs_inc_attr_generation_counter(void)
1740 {
1741 	return atomic_long_inc_return(&nfs_attr_generation_counter);
1742 }
1743 EXPORT_SYMBOL_GPL(nfs_inc_attr_generation_counter);
1744 
nfs_fattr_init(struct nfs_fattr * fattr)1745 void nfs_fattr_init(struct nfs_fattr *fattr)
1746 {
1747 	fattr->valid = 0;
1748 	fattr->time_start = jiffies;
1749 	fattr->gencount = nfs_inc_attr_generation_counter();
1750 	fattr->owner_name = NULL;
1751 	fattr->group_name = NULL;
1752 	fattr->mdsthreshold = NULL;
1753 }
1754 EXPORT_SYMBOL_GPL(nfs_fattr_init);
1755 
1756 /**
1757  * nfs_fattr_set_barrier
1758  * @fattr: attributes
1759  *
1760  * Used to set a barrier after an attribute was updated. This
1761  * barrier ensures that older attributes from RPC calls that may
1762  * have raced with our update cannot clobber these new values.
1763  * Note that you are still responsible for ensuring that other
1764  * operations which change the attribute on the server do not
1765  * collide.
1766  */
nfs_fattr_set_barrier(struct nfs_fattr * fattr)1767 void nfs_fattr_set_barrier(struct nfs_fattr *fattr)
1768 {
1769 	fattr->gencount = nfs_inc_attr_generation_counter();
1770 }
1771 
nfs_alloc_fattr(void)1772 struct nfs_fattr *nfs_alloc_fattr(void)
1773 {
1774 	struct nfs_fattr *fattr;
1775 
1776 	fattr = kmalloc(sizeof(*fattr), GFP_KERNEL);
1777 	if (fattr != NULL) {
1778 		nfs_fattr_init(fattr);
1779 		fattr->label = NULL;
1780 	}
1781 	return fattr;
1782 }
1783 EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
1784 
nfs_alloc_fattr_with_label(struct nfs_server * server)1785 struct nfs_fattr *nfs_alloc_fattr_with_label(struct nfs_server *server)
1786 {
1787 	struct nfs_fattr *fattr = nfs_alloc_fattr();
1788 
1789 	if (!fattr)
1790 		return NULL;
1791 
1792 	fattr->label = nfs4_label_alloc(server, GFP_KERNEL);
1793 	if (IS_ERR(fattr->label)) {
1794 		kfree(fattr);
1795 		return NULL;
1796 	}
1797 
1798 	return fattr;
1799 }
1800 EXPORT_SYMBOL_GPL(nfs_alloc_fattr_with_label);
1801 
nfs_alloc_fhandle(void)1802 struct nfs_fh *nfs_alloc_fhandle(void)
1803 {
1804 	struct nfs_fh *fh;
1805 
1806 	fh = kmalloc(sizeof(struct nfs_fh), GFP_KERNEL);
1807 	if (fh != NULL)
1808 		fh->size = 0;
1809 	return fh;
1810 }
1811 EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
1812 
1813 #ifdef NFS_DEBUG
1814 /*
1815  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1816  *                             in the same way that wireshark does
1817  *
1818  * @fh: file handle
1819  *
1820  * For debugging only.
1821  */
_nfs_display_fhandle_hash(const struct nfs_fh * fh)1822 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1823 {
1824 	/* wireshark uses 32-bit AUTODIN crc and does a bitwise
1825 	 * not on the result */
1826 	return nfs_fhandle_hash(fh);
1827 }
1828 EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
1829 
1830 /*
1831  * _nfs_display_fhandle - display an NFS file handle on the console
1832  *
1833  * @fh: file handle to display
1834  * @caption: display caption
1835  *
1836  * For debugging only.
1837  */
_nfs_display_fhandle(const struct nfs_fh * fh,const char * caption)1838 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1839 {
1840 	unsigned short i;
1841 
1842 	if (fh == NULL || fh->size == 0) {
1843 		printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1844 		return;
1845 	}
1846 
1847 	printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1848 	       caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1849 	for (i = 0; i < fh->size; i += 16) {
1850 		__be32 *pos = (__be32 *)&fh->data[i];
1851 
1852 		switch ((fh->size - i - 1) >> 2) {
1853 		case 0:
1854 			printk(KERN_DEFAULT " %08x\n",
1855 				be32_to_cpup(pos));
1856 			break;
1857 		case 1:
1858 			printk(KERN_DEFAULT " %08x %08x\n",
1859 				be32_to_cpup(pos), be32_to_cpup(pos + 1));
1860 			break;
1861 		case 2:
1862 			printk(KERN_DEFAULT " %08x %08x %08x\n",
1863 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1864 				be32_to_cpup(pos + 2));
1865 			break;
1866 		default:
1867 			printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1868 				be32_to_cpup(pos), be32_to_cpup(pos + 1),
1869 				be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1870 		}
1871 	}
1872 }
1873 EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
1874 #endif
1875 
1876 /**
1877  * nfs_inode_attrs_cmp_generic - compare attributes
1878  * @fattr: attributes
1879  * @inode: pointer to inode
1880  *
1881  * Attempt to divine whether or not an RPC call reply carrying stale
1882  * attributes got scheduled after another call carrying updated ones.
1883  * Note also the check for wraparound of 'attr_gencount'
1884  *
1885  * The function returns '1' if it thinks the attributes in @fattr are
1886  * more recent than the ones cached in @inode. Otherwise it returns
1887  * the value '0'.
1888  */
nfs_inode_attrs_cmp_generic(const struct nfs_fattr * fattr,const struct inode * inode)1889 static int nfs_inode_attrs_cmp_generic(const struct nfs_fattr *fattr,
1890 				       const struct inode *inode)
1891 {
1892 	unsigned long attr_gencount = NFS_I(inode)->attr_gencount;
1893 
1894 	return (long)(fattr->gencount - attr_gencount) > 0 ||
1895 	       (long)(attr_gencount - nfs_read_attr_generation_counter()) > 0;
1896 }
1897 
1898 /**
1899  * nfs_inode_attrs_cmp_monotonic - compare attributes
1900  * @fattr: attributes
1901  * @inode: pointer to inode
1902  *
1903  * Attempt to divine whether or not an RPC call reply carrying stale
1904  * attributes got scheduled after another call carrying updated ones.
1905  *
1906  * We assume that the server observes monotonic semantics for
1907  * the change attribute, so a larger value means that the attributes in
1908  * @fattr are more recent, in which case the function returns the
1909  * value '1'.
1910  * A return value of '0' indicates no measurable change
1911  * A return value of '-1' means that the attributes in @inode are
1912  * more recent.
1913  */
nfs_inode_attrs_cmp_monotonic(const struct nfs_fattr * fattr,const struct inode * inode)1914 static int nfs_inode_attrs_cmp_monotonic(const struct nfs_fattr *fattr,
1915 					 const struct inode *inode)
1916 {
1917 	s64 diff = fattr->change_attr - inode_peek_iversion_raw(inode);
1918 	if (diff > 0)
1919 		return 1;
1920 	return diff == 0 ? 0 : -1;
1921 }
1922 
1923 /**
1924  * nfs_inode_attrs_cmp_strict_monotonic - compare attributes
1925  * @fattr: attributes
1926  * @inode: pointer to inode
1927  *
1928  * Attempt to divine whether or not an RPC call reply carrying stale
1929  * attributes got scheduled after another call carrying updated ones.
1930  *
1931  * We assume that the server observes strictly monotonic semantics for
1932  * the change attribute, so a larger value means that the attributes in
1933  * @fattr are more recent, in which case the function returns the
1934  * value '1'.
1935  * A return value of '-1' means that the attributes in @inode are
1936  * more recent or unchanged.
1937  */
nfs_inode_attrs_cmp_strict_monotonic(const struct nfs_fattr * fattr,const struct inode * inode)1938 static int nfs_inode_attrs_cmp_strict_monotonic(const struct nfs_fattr *fattr,
1939 						const struct inode *inode)
1940 {
1941 	return  nfs_inode_attrs_cmp_monotonic(fattr, inode) > 0 ? 1 : -1;
1942 }
1943 
1944 /**
1945  * nfs_inode_attrs_cmp - compare attributes
1946  * @fattr: attributes
1947  * @inode: pointer to inode
1948  *
1949  * This function returns '1' if it thinks the attributes in @fattr are
1950  * more recent than the ones cached in @inode. It returns '-1' if
1951  * the attributes in @inode are more recent than the ones in @fattr,
1952  * and it returns 0 if not sure.
1953  */
nfs_inode_attrs_cmp(const struct nfs_fattr * fattr,const struct inode * inode)1954 static int nfs_inode_attrs_cmp(const struct nfs_fattr *fattr,
1955 			       const struct inode *inode)
1956 {
1957 	if (nfs_inode_attrs_cmp_generic(fattr, inode) > 0)
1958 		return 1;
1959 	switch (NFS_SERVER(inode)->change_attr_type) {
1960 	case NFS4_CHANGE_TYPE_IS_UNDEFINED:
1961 		break;
1962 	case NFS4_CHANGE_TYPE_IS_TIME_METADATA:
1963 		if (!(fattr->valid & NFS_ATTR_FATTR_CHANGE))
1964 			break;
1965 		return nfs_inode_attrs_cmp_monotonic(fattr, inode);
1966 	default:
1967 		if (!(fattr->valid & NFS_ATTR_FATTR_CHANGE))
1968 			break;
1969 		return nfs_inode_attrs_cmp_strict_monotonic(fattr, inode);
1970 	}
1971 	return 0;
1972 }
1973 
1974 /**
1975  * nfs_inode_finish_partial_attr_update - complete a previous inode update
1976  * @fattr: attributes
1977  * @inode: pointer to inode
1978  *
1979  * Returns '1' if the last attribute update left the inode cached
1980  * attributes in a partially unrevalidated state, and @fattr
1981  * matches the change attribute of that partial update.
1982  * Otherwise returns '0'.
1983  */
nfs_inode_finish_partial_attr_update(const struct nfs_fattr * fattr,const struct inode * inode)1984 static int nfs_inode_finish_partial_attr_update(const struct nfs_fattr *fattr,
1985 						const struct inode *inode)
1986 {
1987 	const unsigned long check_valid =
1988 		NFS_INO_INVALID_ATIME | NFS_INO_INVALID_CTIME |
1989 		NFS_INO_INVALID_MTIME | NFS_INO_INVALID_SIZE |
1990 		NFS_INO_INVALID_BLOCKS | NFS_INO_INVALID_OTHER |
1991 		NFS_INO_INVALID_NLINK | NFS_INO_INVALID_BTIME;
1992 	unsigned long cache_validity = NFS_I(inode)->cache_validity;
1993 	enum nfs4_change_attr_type ctype = NFS_SERVER(inode)->change_attr_type;
1994 
1995 	if (ctype != NFS4_CHANGE_TYPE_IS_UNDEFINED &&
1996 	    !(cache_validity & NFS_INO_INVALID_CHANGE) &&
1997 	    (cache_validity & check_valid) != 0 &&
1998 	    (fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1999 	    nfs_inode_attrs_cmp_monotonic(fattr, inode) == 0)
2000 		return 1;
2001 	return 0;
2002 }
2003 
nfs_ooo_merge(struct nfs_inode * nfsi,u64 start,u64 end)2004 static void nfs_ooo_merge(struct nfs_inode *nfsi,
2005 			  u64 start, u64 end)
2006 {
2007 	int i, cnt;
2008 
2009 	if (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER)
2010 		/* No point merging anything */
2011 		return;
2012 
2013 	if (!nfsi->ooo) {
2014 		nfsi->ooo = kmalloc(sizeof(*nfsi->ooo), GFP_ATOMIC);
2015 		if (!nfsi->ooo) {
2016 			nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
2017 			return;
2018 		}
2019 		nfsi->ooo->cnt = 0;
2020 	}
2021 
2022 	/* add this range, merging if possible */
2023 	cnt = nfsi->ooo->cnt;
2024 	for (i = 0; i < cnt; i++) {
2025 		if (end == nfsi->ooo->gap[i].start)
2026 			end = nfsi->ooo->gap[i].end;
2027 		else if (start == nfsi->ooo->gap[i].end)
2028 			start = nfsi->ooo->gap[i].start;
2029 		else
2030 			continue;
2031 		/* Remove 'i' from table and loop to insert the new range */
2032 		cnt -= 1;
2033 		nfsi->ooo->gap[i] = nfsi->ooo->gap[cnt];
2034 		i = -1;
2035 	}
2036 	if (start != end) {
2037 		if (cnt >= ARRAY_SIZE(nfsi->ooo->gap)) {
2038 			nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
2039 			kfree(nfsi->ooo);
2040 			nfsi->ooo = NULL;
2041 			return;
2042 		}
2043 		nfsi->ooo->gap[cnt].start = start;
2044 		nfsi->ooo->gap[cnt].end = end;
2045 		cnt += 1;
2046 	}
2047 	nfsi->ooo->cnt = cnt;
2048 }
2049 
nfs_ooo_record(struct nfs_inode * nfsi,struct nfs_fattr * fattr)2050 static void nfs_ooo_record(struct nfs_inode *nfsi,
2051 			   struct nfs_fattr *fattr)
2052 {
2053 	/* This reply was out-of-order, so record in the
2054 	 * pre/post change id, possibly cancelling
2055 	 * gaps created when iversion was jumpped forward.
2056 	 */
2057 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) &&
2058 	    (fattr->valid & NFS_ATTR_FATTR_PRECHANGE))
2059 		nfs_ooo_merge(nfsi,
2060 			      fattr->change_attr,
2061 			      fattr->pre_change_attr);
2062 }
2063 
nfs_refresh_inode_locked(struct inode * inode,struct nfs_fattr * fattr)2064 static int nfs_refresh_inode_locked(struct inode *inode,
2065 				    struct nfs_fattr *fattr)
2066 {
2067 	int attr_cmp = nfs_inode_attrs_cmp(fattr, inode);
2068 	int ret = 0;
2069 
2070 	trace_nfs_refresh_inode_enter(inode);
2071 
2072 	if (attr_cmp > 0 || nfs_inode_finish_partial_attr_update(fattr, inode))
2073 		ret = nfs_update_inode(inode, fattr);
2074 	else {
2075 		nfs_ooo_record(NFS_I(inode), fattr);
2076 
2077 		if (attr_cmp == 0)
2078 			ret = nfs_check_inode_attributes(inode, fattr);
2079 	}
2080 
2081 	trace_nfs_refresh_inode_exit(inode, ret);
2082 	return ret;
2083 }
2084 
2085 /**
2086  * nfs_refresh_inode - try to update the inode attribute cache
2087  * @inode: pointer to inode
2088  * @fattr: updated attributes
2089  *
2090  * Check that an RPC call that returned attributes has not overlapped with
2091  * other recent updates of the inode metadata, then decide whether it is
2092  * safe to do a full update of the inode attributes, or whether just to
2093  * call nfs_check_inode_attributes.
2094  */
nfs_refresh_inode(struct inode * inode,struct nfs_fattr * fattr)2095 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
2096 {
2097 	int status;
2098 
2099 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
2100 		return 0;
2101 	spin_lock(&inode->i_lock);
2102 	status = nfs_refresh_inode_locked(inode, fattr);
2103 	spin_unlock(&inode->i_lock);
2104 
2105 	return status;
2106 }
2107 EXPORT_SYMBOL_GPL(nfs_refresh_inode);
2108 
nfs_post_op_update_inode_locked(struct inode * inode,struct nfs_fattr * fattr,unsigned int invalid)2109 static int nfs_post_op_update_inode_locked(struct inode *inode,
2110 		struct nfs_fattr *fattr, unsigned int invalid)
2111 {
2112 	if (S_ISDIR(inode->i_mode))
2113 		invalid |= NFS_INO_INVALID_DATA;
2114 	nfs_set_cache_invalid(inode, invalid);
2115 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
2116 		return 0;
2117 	return nfs_refresh_inode_locked(inode, fattr);
2118 }
2119 
2120 /**
2121  * nfs_post_op_update_inode - try to update the inode attribute cache
2122  * @inode: pointer to inode
2123  * @fattr: updated attributes
2124  *
2125  * After an operation that has changed the inode metadata, mark the
2126  * attribute cache as being invalid, then try to update it.
2127  *
2128  * NB: if the server didn't return any post op attributes, this
2129  * function will force the retrieval of attributes before the next
2130  * NFS request.  Thus it should be used only for operations that
2131  * are expected to change one or more attributes, to avoid
2132  * unnecessary NFS requests and trips through nfs_update_inode().
2133  */
nfs_post_op_update_inode(struct inode * inode,struct nfs_fattr * fattr)2134 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
2135 {
2136 	int status;
2137 
2138 	spin_lock(&inode->i_lock);
2139 	nfs_fattr_set_barrier(fattr);
2140 	status = nfs_post_op_update_inode_locked(inode, fattr,
2141 			NFS_INO_INVALID_CHANGE
2142 			| NFS_INO_INVALID_CTIME
2143 			| NFS_INO_REVAL_FORCED);
2144 	spin_unlock(&inode->i_lock);
2145 
2146 	return status;
2147 }
2148 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
2149 
2150 /**
2151  * nfs_post_op_update_inode_force_wcc_locked - update the inode attribute cache
2152  * @inode: pointer to inode
2153  * @fattr: updated attributes
2154  *
2155  * After an operation that has changed the inode metadata, mark the
2156  * attribute cache as being invalid, then try to update it. Fake up
2157  * weak cache consistency data, if none exist.
2158  *
2159  * This function is mainly designed to be used by the ->write_done() functions.
2160  */
nfs_post_op_update_inode_force_wcc_locked(struct inode * inode,struct nfs_fattr * fattr)2161 int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr)
2162 {
2163 	int attr_cmp = nfs_inode_attrs_cmp(fattr, inode);
2164 	int status;
2165 
2166 	/* Don't do a WCC update if these attributes are already stale */
2167 	if (attr_cmp < 0)
2168 		return 0;
2169 	if ((fattr->valid & NFS_ATTR_FATTR) == 0 || !attr_cmp) {
2170 		/* Record the pre/post change info before clearing PRECHANGE */
2171 		nfs_ooo_record(NFS_I(inode), fattr);
2172 		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
2173 				| NFS_ATTR_FATTR_PRESIZE
2174 				| NFS_ATTR_FATTR_PREMTIME
2175 				| NFS_ATTR_FATTR_PRECTIME);
2176 		goto out_noforce;
2177 	}
2178 	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
2179 			(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
2180 		fattr->pre_change_attr = inode_peek_iversion_raw(inode);
2181 		fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
2182 	}
2183 	if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
2184 			(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
2185 		fattr->pre_ctime = inode_get_ctime(inode);
2186 		fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
2187 	}
2188 	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
2189 			(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
2190 		fattr->pre_mtime = inode_get_mtime(inode);
2191 		fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
2192 	}
2193 	if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
2194 			(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
2195 		fattr->pre_size = i_size_read(inode);
2196 		fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
2197 	}
2198 out_noforce:
2199 	status = nfs_post_op_update_inode_locked(inode, fattr,
2200 			NFS_INO_INVALID_CHANGE
2201 			| NFS_INO_INVALID_CTIME
2202 			| NFS_INO_INVALID_MTIME
2203 			| NFS_INO_INVALID_BLOCKS);
2204 	return status;
2205 }
2206 
2207 /**
2208  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
2209  * @inode: pointer to inode
2210  * @fattr: updated attributes
2211  *
2212  * After an operation that has changed the inode metadata, mark the
2213  * attribute cache as being invalid, then try to update it. Fake up
2214  * weak cache consistency data, if none exist.
2215  *
2216  * This function is mainly designed to be used by the ->write_done() functions.
2217  */
nfs_post_op_update_inode_force_wcc(struct inode * inode,struct nfs_fattr * fattr)2218 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
2219 {
2220 	int status;
2221 
2222 	spin_lock(&inode->i_lock);
2223 	nfs_fattr_set_barrier(fattr);
2224 	status = nfs_post_op_update_inode_force_wcc_locked(inode, fattr);
2225 	spin_unlock(&inode->i_lock);
2226 	return status;
2227 }
2228 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
2229 
2230 
2231 /*
2232  * Many nfs protocol calls return the new file attributes after
2233  * an operation.  Here we update the inode to reflect the state
2234  * of the server's inode.
2235  *
2236  * This is a bit tricky because we have to make sure all dirty pages
2237  * have been sent off to the server before calling invalidate_inode_pages.
2238  * To make sure no other process adds more write requests while we try
2239  * our best to flush them, we make them sleep during the attribute refresh.
2240  *
2241  * A very similar scenario holds for the dir cache.
2242  */
nfs_update_inode(struct inode * inode,struct nfs_fattr * fattr)2243 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
2244 {
2245 	struct nfs_server *server = NFS_SERVER(inode);
2246 	struct nfs_inode *nfsi = NFS_I(inode);
2247 	loff_t cur_isize, new_isize;
2248 	u64 fattr_supported = server->fattr_valid;
2249 	unsigned long invalid = 0;
2250 	unsigned long now = jiffies;
2251 	unsigned long save_cache_validity;
2252 	bool have_writers = nfs_file_has_buffered_writers(nfsi);
2253 	bool cache_revalidated = true;
2254 	bool attr_changed = false;
2255 	bool have_delegation;
2256 
2257 	dfprintk(VFS, "NFS: %s(%s/%lu fh_crc=0x%08x ct=%d info=0x%llx)\n",
2258 			__func__, inode->i_sb->s_id, inode->i_ino,
2259 			nfs_display_fhandle_hash(NFS_FH(inode)),
2260 			icount_read(inode), fattr->valid);
2261 
2262 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
2263 		/* Only a mounted-on-fileid? Just exit */
2264 		if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
2265 			return 0;
2266 	/* Has the inode gone and changed behind our back? */
2267 	} else if (nfsi->fileid != fattr->fileid) {
2268 		/* Is this perhaps the mounted-on fileid? */
2269 		if ((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) &&
2270 		    nfsi->fileid == fattr->mounted_on_fileid)
2271 			return 0;
2272 		printk(KERN_ERR "NFS: server %s error: fileid changed\n"
2273 			"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
2274 			NFS_SERVER(inode)->nfs_client->cl_hostname,
2275 			inode->i_sb->s_id, (long long)nfsi->fileid,
2276 			(long long)fattr->fileid);
2277 		goto out_err;
2278 	}
2279 
2280 	/*
2281 	 * Make sure the inode's type hasn't changed.
2282 	 */
2283 	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && inode_wrong_type(inode, fattr->mode)) {
2284 		/*
2285 		* Big trouble! The inode has become a different object.
2286 		*/
2287 		printk(KERN_DEBUG "NFS: %s: inode %lu mode changed, %07o to %07o\n",
2288 				__func__, inode->i_ino, inode->i_mode, fattr->mode);
2289 		goto out_err;
2290 	}
2291 
2292 	/* Update the fsid? */
2293 	if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
2294 			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
2295 			!IS_AUTOMOUNT(inode))
2296 		server->fsid = fattr->fsid;
2297 
2298 	/* Save the delegation state before clearing cache_validity */
2299 	have_delegation = nfs_have_delegated_attributes(inode);
2300 
2301 	/*
2302 	 * Update the read time so we don't revalidate too often.
2303 	 */
2304 	nfsi->read_cache_jiffies = fattr->time_start;
2305 
2306 	/* Fix up any delegated attributes in the struct nfs_fattr */
2307 	nfs_fattr_fixup_delegated(inode, fattr);
2308 
2309 	save_cache_validity = nfsi->cache_validity;
2310 	nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
2311 			| NFS_INO_INVALID_ATIME
2312 			| NFS_INO_REVAL_FORCED
2313 			| NFS_INO_INVALID_BLOCKS);
2314 
2315 	/* Do atomic weak cache consistency updates */
2316 	nfs_wcc_update_inode(inode, fattr);
2317 
2318 	if (pnfs_layoutcommit_outstanding(inode)) {
2319 		nfsi->cache_validity |=
2320 			save_cache_validity &
2321 			(NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_CTIME |
2322 			 NFS_INO_INVALID_MTIME | NFS_INO_INVALID_SIZE |
2323 			 NFS_INO_INVALID_BLOCKS);
2324 		cache_revalidated = false;
2325 	}
2326 
2327 	/* More cache consistency checks */
2328 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
2329 		if (!have_writers && nfsi->ooo && nfsi->ooo->cnt == 1 &&
2330 		    nfsi->ooo->gap[0].end == inode_peek_iversion_raw(inode)) {
2331 			/* There is one remaining gap that hasn't been
2332 			 * merged into iversion - do that now.
2333 			 */
2334 			inode_set_iversion_raw(inode, nfsi->ooo->gap[0].start);
2335 			kfree(nfsi->ooo);
2336 			nfsi->ooo = NULL;
2337 		}
2338 		if (!inode_eq_iversion_raw(inode, fattr->change_attr)) {
2339 			/* Could it be a race with writeback? */
2340 			if (!(have_writers || have_delegation)) {
2341 				invalid |= NFS_INO_INVALID_DATA
2342 					| NFS_INO_INVALID_ACCESS
2343 					| NFS_INO_INVALID_ACL
2344 					| NFS_INO_INVALID_XATTR;
2345 				/* Force revalidate of all attributes */
2346 				save_cache_validity |= NFS_INO_INVALID_CTIME
2347 					| NFS_INO_INVALID_MTIME
2348 					| NFS_INO_INVALID_SIZE
2349 					| NFS_INO_INVALID_BLOCKS
2350 					| NFS_INO_INVALID_NLINK
2351 					| NFS_INO_INVALID_MODE
2352 					| NFS_INO_INVALID_OTHER
2353 					| NFS_INO_INVALID_BTIME;
2354 				if (S_ISDIR(inode->i_mode))
2355 					nfs_force_lookup_revalidate(inode);
2356 				attr_changed = true;
2357 				dprintk("NFS: change_attr change on server for file %s/%ld\n",
2358 						inode->i_sb->s_id,
2359 						inode->i_ino);
2360 			} else if (!have_delegation) {
2361 				nfs_ooo_record(nfsi, fattr);
2362 				nfs_ooo_merge(nfsi, inode_peek_iversion_raw(inode),
2363 					      fattr->change_attr);
2364 			}
2365 			inode_set_iversion_raw(inode, fattr->change_attr);
2366 		}
2367 	} else {
2368 		nfsi->cache_validity |=
2369 			save_cache_validity & NFS_INO_INVALID_CHANGE;
2370 		if (!have_delegation ||
2371 		    (nfsi->cache_validity & NFS_INO_INVALID_CHANGE) != 0)
2372 			cache_revalidated = false;
2373 	}
2374 
2375 	if (fattr->valid & NFS_ATTR_FATTR_MTIME)
2376 		inode_set_mtime_to_ts(inode, fattr->mtime);
2377 	else if (fattr_supported & NFS_ATTR_FATTR_MTIME)
2378 		nfsi->cache_validity |=
2379 			save_cache_validity & NFS_INO_INVALID_MTIME;
2380 
2381 	if (fattr->valid & NFS_ATTR_FATTR_CTIME)
2382 		inode_set_ctime_to_ts(inode, fattr->ctime);
2383 	else if (fattr_supported & NFS_ATTR_FATTR_CTIME)
2384 		nfsi->cache_validity |=
2385 			save_cache_validity & NFS_INO_INVALID_CTIME;
2386 
2387 	if (fattr->valid & NFS_ATTR_FATTR_BTIME)
2388 		nfsi->btime = fattr->btime;
2389 	else if (fattr_supported & NFS_ATTR_FATTR_BTIME)
2390 		nfsi->cache_validity |=
2391 			save_cache_validity & NFS_INO_INVALID_BTIME;
2392 
2393 	/* Check if our cached file size is stale */
2394 	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
2395 		new_isize = nfs_size_to_loff_t(fattr->size);
2396 		cur_isize = i_size_read(inode);
2397 		if (new_isize != cur_isize && !have_delegation) {
2398 			/* Do we perhaps have any outstanding writes, or has
2399 			 * the file grown beyond our last write? */
2400 			if (!nfs_have_writebacks(inode) || new_isize > cur_isize) {
2401 				trace_nfs_size_update(inode, new_isize);
2402 				i_size_write(inode, new_isize);
2403 				if (!have_writers)
2404 					invalid |= NFS_INO_INVALID_DATA;
2405 			}
2406 		}
2407 		if (new_isize == 0 &&
2408 		    !(fattr->valid & (NFS_ATTR_FATTR_SPACE_USED |
2409 				      NFS_ATTR_FATTR_BLOCKS_USED))) {
2410 			fattr->du.nfs3.used = 0;
2411 			fattr->valid |= NFS_ATTR_FATTR_SPACE_USED;
2412 		}
2413 	} else
2414 		nfsi->cache_validity |=
2415 			save_cache_validity & NFS_INO_INVALID_SIZE;
2416 
2417 	if (fattr->valid & NFS_ATTR_FATTR_ATIME)
2418 		inode_set_atime_to_ts(inode, fattr->atime);
2419 	else if (fattr_supported & NFS_ATTR_FATTR_ATIME)
2420 		nfsi->cache_validity |=
2421 			save_cache_validity & NFS_INO_INVALID_ATIME;
2422 
2423 	if (fattr->valid & NFS_ATTR_FATTR_MODE) {
2424 		if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
2425 			umode_t newmode = inode->i_mode & S_IFMT;
2426 			newmode |= fattr->mode & S_IALLUGO;
2427 			inode->i_mode = newmode;
2428 			invalid |= NFS_INO_INVALID_ACCESS
2429 				| NFS_INO_INVALID_ACL;
2430 		}
2431 	} else if (fattr_supported & NFS_ATTR_FATTR_MODE)
2432 		nfsi->cache_validity |=
2433 			save_cache_validity & NFS_INO_INVALID_MODE;
2434 
2435 	if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
2436 		if (!uid_eq(inode->i_uid, fattr->uid)) {
2437 			invalid |= NFS_INO_INVALID_ACCESS
2438 				| NFS_INO_INVALID_ACL;
2439 			inode->i_uid = fattr->uid;
2440 		}
2441 	} else if (fattr_supported & NFS_ATTR_FATTR_OWNER)
2442 		nfsi->cache_validity |=
2443 			save_cache_validity & NFS_INO_INVALID_OTHER;
2444 
2445 	if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
2446 		if (!gid_eq(inode->i_gid, fattr->gid)) {
2447 			invalid |= NFS_INO_INVALID_ACCESS
2448 				| NFS_INO_INVALID_ACL;
2449 			inode->i_gid = fattr->gid;
2450 		}
2451 	} else if (fattr_supported & NFS_ATTR_FATTR_GROUP)
2452 		nfsi->cache_validity |=
2453 			save_cache_validity & NFS_INO_INVALID_OTHER;
2454 
2455 	if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
2456 		if (inode->i_nlink != fattr->nlink)
2457 			set_nlink(inode, fattr->nlink);
2458 	} else if (fattr_supported & NFS_ATTR_FATTR_NLINK)
2459 		nfsi->cache_validity |=
2460 			save_cache_validity & NFS_INO_INVALID_NLINK;
2461 
2462 	if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
2463 		/*
2464 		 * report the blocks in 512byte units
2465 		 */
2466 		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
2467 	} else if (fattr_supported & NFS_ATTR_FATTR_SPACE_USED)
2468 		nfsi->cache_validity |=
2469 			save_cache_validity & NFS_INO_INVALID_BLOCKS;
2470 
2471 	if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
2472 		inode->i_blocks = fattr->du.nfs2.blocks;
2473 	else if (fattr_supported & NFS_ATTR_FATTR_BLOCKS_USED)
2474 		nfsi->cache_validity |=
2475 			save_cache_validity & NFS_INO_INVALID_BLOCKS;
2476 
2477 	/* Update attrtimeo value if we're out of the unstable period */
2478 	if (attr_changed) {
2479 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
2480 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
2481 		nfsi->attrtimeo_timestamp = now;
2482 		/* Set barrier to be more recent than all outstanding updates */
2483 		nfsi->attr_gencount = nfs_inc_attr_generation_counter();
2484 	} else {
2485 		if (cache_revalidated) {
2486 			if (!time_in_range_open(now, nfsi->attrtimeo_timestamp,
2487 				nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
2488 				nfsi->attrtimeo <<= 1;
2489 				if (nfsi->attrtimeo > NFS_MAXATTRTIMEO(inode))
2490 					nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
2491 			}
2492 			nfsi->attrtimeo_timestamp = now;
2493 		}
2494 		/* Set the barrier to be more recent than this fattr */
2495 		if ((long)(fattr->gencount - nfsi->attr_gencount) > 0)
2496 			nfsi->attr_gencount = fattr->gencount;
2497 	}
2498 
2499 	/* Don't invalidate the data if we were to blame */
2500 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
2501 				|| S_ISLNK(inode->i_mode)))
2502 		invalid &= ~NFS_INO_INVALID_DATA;
2503 	nfs_set_cache_invalid(inode, invalid);
2504 
2505 	return 0;
2506  out_err:
2507 	/*
2508 	 * No need to worry about unhashing the dentry, as the
2509 	 * lookup validation will know that the inode is bad.
2510 	 * (But we fall through to invalidate the caches.)
2511 	 */
2512 	nfs_set_inode_stale_locked(inode);
2513 	return -ESTALE;
2514 }
2515 
nfs_alloc_inode(struct super_block * sb)2516 struct inode *nfs_alloc_inode(struct super_block *sb)
2517 {
2518 	struct nfs_inode *nfsi;
2519 	nfsi = alloc_inode_sb(sb, nfs_inode_cachep, GFP_KERNEL);
2520 	if (!nfsi)
2521 		return NULL;
2522 	nfsi->flags = 0UL;
2523 	nfsi->cache_validity = 0UL;
2524 	nfsi->ooo = NULL;
2525 #if IS_ENABLED(CONFIG_NFS_V4)
2526 	nfsi->nfs4_acl = NULL;
2527 #endif /* CONFIG_NFS_V4 */
2528 #ifdef CONFIG_NFS_V4_2
2529 	nfsi->xattr_cache = NULL;
2530 #endif
2531 	nfs_netfs_inode_init(nfsi);
2532 
2533 	return &nfsi->vfs_inode;
2534 }
2535 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
2536 
nfs_free_inode(struct inode * inode)2537 void nfs_free_inode(struct inode *inode)
2538 {
2539 	kfree(NFS_I(inode)->ooo);
2540 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
2541 }
2542 EXPORT_SYMBOL_GPL(nfs_free_inode);
2543 
nfs4_init_once(struct nfs_inode * nfsi)2544 static inline void nfs4_init_once(struct nfs_inode *nfsi)
2545 {
2546 #if IS_ENABLED(CONFIG_NFS_V4)
2547 	INIT_LIST_HEAD(&nfsi->open_states);
2548 	nfsi->delegation = NULL;
2549 	init_rwsem(&nfsi->rwsem);
2550 	nfsi->layout = NULL;
2551 #endif
2552 }
2553 
init_once(void * foo)2554 static void init_once(void *foo)
2555 {
2556 	struct nfs_inode *nfsi = foo;
2557 
2558 	inode_init_once(&nfsi->vfs_inode);
2559 	INIT_LIST_HEAD(&nfsi->open_files);
2560 	INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
2561 	INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
2562 	nfs4_init_once(nfsi);
2563 }
2564 
nfs_init_inodecache(void)2565 static int __init nfs_init_inodecache(void)
2566 {
2567 	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
2568 					     sizeof(struct nfs_inode),
2569 					     0, (SLAB_RECLAIM_ACCOUNT|
2570 						SLAB_ACCOUNT),
2571 					     init_once);
2572 	if (nfs_inode_cachep == NULL)
2573 		return -ENOMEM;
2574 
2575 	return 0;
2576 }
2577 
nfs_destroy_inodecache(void)2578 static void nfs_destroy_inodecache(void)
2579 {
2580 	/*
2581 	 * Make sure all delayed rcu free inodes are flushed before we
2582 	 * destroy cache.
2583 	 */
2584 	rcu_barrier();
2585 	kmem_cache_destroy(nfs_inode_cachep);
2586 }
2587 
2588 struct workqueue_struct *nfslocaliod_workqueue;
2589 struct workqueue_struct *nfsiod_workqueue;
2590 EXPORT_SYMBOL_GPL(nfsiod_workqueue);
2591 
2592 /*
2593  * Destroy the nfsiod workqueues
2594  */
nfsiod_stop(void)2595 static void nfsiod_stop(void)
2596 {
2597 	struct workqueue_struct *wq;
2598 
2599 	wq = nfsiod_workqueue;
2600 	if (wq != NULL) {
2601 		nfsiod_workqueue = NULL;
2602 		destroy_workqueue(wq);
2603 	}
2604 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
2605 	wq = nfslocaliod_workqueue;
2606 	if (wq != NULL) {
2607 		nfslocaliod_workqueue = NULL;
2608 		destroy_workqueue(wq);
2609 	}
2610 #endif /* CONFIG_NFS_LOCALIO */
2611 }
2612 
2613 /*
2614  * Start the nfsiod workqueues
2615  */
nfsiod_start(void)2616 static int nfsiod_start(void)
2617 {
2618 	dprintk("RPC:       creating workqueue nfsiod\n");
2619 	nfsiod_workqueue = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM | WQ_UNBOUND, 0);
2620 	if (nfsiod_workqueue == NULL)
2621 		return -ENOMEM;
2622 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
2623 	/*
2624 	 * localio writes need to use a normal (non-memreclaim) workqueue.
2625 	 * When we start getting low on space, XFS goes and calls flush_work() on
2626 	 * a non-memreclaim work queue, which causes a priority inversion problem.
2627 	 */
2628 	dprintk("RPC:       creating workqueue nfslocaliod\n");
2629 	nfslocaliod_workqueue = alloc_workqueue("nfslocaliod", WQ_UNBOUND, 0);
2630 	if (unlikely(nfslocaliod_workqueue == NULL)) {
2631 		nfsiod_stop();
2632 		return -ENOMEM;
2633 	}
2634 #endif /* CONFIG_NFS_LOCALIO */
2635 	return 0;
2636 }
2637 
2638 unsigned int nfs_net_id;
2639 EXPORT_SYMBOL_GPL(nfs_net_id);
2640 
nfs_net_init(struct net * net)2641 static int nfs_net_init(struct net *net)
2642 {
2643 	struct nfs_net *nn = net_generic(net, nfs_net_id);
2644 	int err;
2645 
2646 	nfs_clients_init(net);
2647 
2648 	if (!rpc_proc_register(net, &nn->rpcstats)) {
2649 		err = -ENOMEM;
2650 		goto err_proc_rpc;
2651 	}
2652 
2653 	err = nfs_fs_proc_net_init(net);
2654 	if (err)
2655 		goto err_proc_nfs;
2656 
2657 	return 0;
2658 
2659 err_proc_nfs:
2660 	rpc_proc_unregister(net, "nfs");
2661 err_proc_rpc:
2662 	nfs_clients_exit(net);
2663 	return err;
2664 }
2665 
nfs_net_exit(struct net * net)2666 static void nfs_net_exit(struct net *net)
2667 {
2668 	rpc_proc_unregister(net, "nfs");
2669 	nfs_fs_proc_net_exit(net);
2670 	nfs_clients_exit(net);
2671 }
2672 
2673 static struct pernet_operations nfs_net_ops = {
2674 	.init = nfs_net_init,
2675 	.exit = nfs_net_exit,
2676 	.id   = &nfs_net_id,
2677 	.size = sizeof(struct nfs_net),
2678 };
2679 
2680 #ifdef CONFIG_KEYS
2681 static struct key *nfs_keyring;
2682 
nfs_init_keyring(void)2683 static int __init nfs_init_keyring(void)
2684 {
2685 	nfs_keyring = keyring_alloc(".nfs",
2686 			     GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
2687 			     current_cred(),
2688 			     (KEY_POS_ALL & ~KEY_POS_SETATTR) |
2689 			     (KEY_USR_ALL & ~KEY_USR_SETATTR),
2690 			     KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
2691 	return PTR_ERR_OR_ZERO(nfs_keyring);
2692 }
2693 
nfs_exit_keyring(void)2694 static void nfs_exit_keyring(void)
2695 {
2696 	key_put(nfs_keyring);
2697 }
2698 #else
nfs_init_keyring(void)2699 static inline int nfs_init_keyring(void)
2700 {
2701 	return 0;
2702 }
2703 
nfs_exit_keyring(void)2704 static inline void nfs_exit_keyring(void)
2705 {
2706 }
2707 #endif /* CONFIG_KEYS */
2708 
2709 /*
2710  * Initialize NFS
2711  */
init_nfs_fs(void)2712 static int __init init_nfs_fs(void)
2713 {
2714 	int err;
2715 
2716 	err = nfs_init_keyring();
2717 	if (err)
2718 		return err;
2719 
2720 	err = nfs_sysfs_init();
2721 	if (err < 0)
2722 		goto out10;
2723 
2724 	err = register_pernet_subsys(&nfs_net_ops);
2725 	if (err < 0)
2726 		goto out9;
2727 
2728 	err = nfsiod_start();
2729 	if (err)
2730 		goto out7;
2731 
2732 	err = nfs_fs_proc_init();
2733 	if (err)
2734 		goto out6;
2735 
2736 	err = nfs_init_nfspagecache();
2737 	if (err)
2738 		goto out5;
2739 
2740 	err = nfs_init_inodecache();
2741 	if (err)
2742 		goto out4;
2743 
2744 	err = nfs_init_readpagecache();
2745 	if (err)
2746 		goto out3;
2747 
2748 	err = nfs_init_writepagecache();
2749 	if (err)
2750 		goto out2;
2751 
2752 	err = nfs_init_directcache();
2753 	if (err)
2754 		goto out1;
2755 
2756 	err = register_nfs_fs();
2757 	if (err)
2758 		goto out0;
2759 
2760 	return 0;
2761 out0:
2762 	nfs_destroy_directcache();
2763 out1:
2764 	nfs_destroy_writepagecache();
2765 out2:
2766 	nfs_destroy_readpagecache();
2767 out3:
2768 	nfs_destroy_inodecache();
2769 out4:
2770 	nfs_destroy_nfspagecache();
2771 out5:
2772 	nfs_fs_proc_exit();
2773 out6:
2774 	nfsiod_stop();
2775 out7:
2776 	unregister_pernet_subsys(&nfs_net_ops);
2777 out9:
2778 	nfs_sysfs_exit();
2779 out10:
2780 	nfs_exit_keyring();
2781 	return err;
2782 }
2783 
exit_nfs_fs(void)2784 static void __exit exit_nfs_fs(void)
2785 {
2786 	nfs_destroy_directcache();
2787 	nfs_destroy_writepagecache();
2788 	nfs_destroy_readpagecache();
2789 	nfs_destroy_inodecache();
2790 	nfs_destroy_nfspagecache();
2791 	unregister_pernet_subsys(&nfs_net_ops);
2792 	unregister_nfs_fs();
2793 	nfs_fs_proc_exit();
2794 	nfsiod_stop();
2795 	nfs_sysfs_exit();
2796 	nfs_exit_keyring();
2797 }
2798 
2799 /* Not quite true; I just maintain it */
2800 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
2801 MODULE_DESCRIPTION("NFS client support");
2802 MODULE_LICENSE("GPL");
2803 module_param(enable_ino64, bool, 0644);
2804 
2805 module_init(init_nfs_fs)
2806 module_exit(exit_nfs_fs)
2807