xref: /linux/include/linux/nfs_fs.h (revision b85900e91c8402bedc1db14e6d293e26f25d30d4)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  linux/include/linux/nfs_fs.h
4  *
5  *  Copyright (C) 1992  Rick Sladkey
6  *
7  *  OS-specific nfs filesystem definitions and declarations
8  */
9 #ifndef _LINUX_NFS_FS_H
10 #define _LINUX_NFS_FS_H
11 
12 #include <uapi/linux/nfs_fs.h>
13 
14 
15 /*
16  * Enable dprintk() debugging support for nfs client.
17  */
18 #ifdef CONFIG_NFS_DEBUG
19 # define NFS_DEBUG
20 #endif
21 
22 #include <linux/in.h>
23 #include <linux/mm.h>
24 #include <linux/pagemap.h>
25 #include <linux/rbtree.h>
26 #include <linux/refcount.h>
27 #include <linux/rwsem.h>
28 #include <linux/wait.h>
29 
30 #include <linux/sunrpc/debug.h>
31 #include <linux/sunrpc/auth.h>
32 #include <linux/sunrpc/clnt.h>
33 
34 #ifdef CONFIG_NFS_FSCACHE
35 #include <linux/netfs.h>
36 #endif
37 
38 #include <linux/nfs.h>
39 #include <linux/nfs2.h>
40 #include <linux/nfs3.h>
41 #include <linux/nfs4.h>
42 #include <linux/nfs_xdr.h>
43 #include <linux/nfs_fs_sb.h>
44 
45 #include <linux/mempool.h>
46 
47 /*
48  * These are the default for number of transports to different server IPs
49  */
50 #define NFS_MAX_TRANSPORTS 16
51 
52 /*
53  * Size of the NFS directory verifier
54  */
55 #define NFS_DIR_VERIFIER_SIZE		2
56 
57 /*
58  * NFSv3/v4 Access mode cache entry
59  */
60 struct nfs_access_entry {
61 	struct rb_node		rb_node;
62 	struct list_head	lru;
63 	kuid_t			fsuid;
64 	kgid_t			fsgid;
65 	struct group_info	*group_info;
66 	u64			timestamp;
67 	__u32			mask;
68 	struct rcu_head		rcu_head;
69 };
70 
71 struct nfs_lock_context {
72 	refcount_t count;
73 	struct list_head list;
74 	struct nfs_open_context *open_context;
75 	fl_owner_t lockowner;
76 	atomic_t io_count;
77 	struct rcu_head	rcu_head;
78 };
79 
80 struct nfs_file_localio {
81 	struct nfsd_file __rcu *ro_file;
82 	struct nfsd_file __rcu *rw_file;
83 	struct list_head list;
84 	void __rcu *nfs_uuid; /* opaque pointer to 'nfs_uuid_t' */
85 };
86 
nfs_localio_file_init(struct nfs_file_localio * nfl)87 static inline void nfs_localio_file_init(struct nfs_file_localio *nfl)
88 {
89 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
90 	nfl->ro_file = NULL;
91 	nfl->rw_file = NULL;
92 	INIT_LIST_HEAD(&nfl->list);
93 	nfl->nfs_uuid = NULL;
94 #endif
95 }
96 
97 struct nfs4_state;
98 struct nfs_open_context {
99 	struct nfs_lock_context lock_context;
100 	fl_owner_t flock_owner;
101 	struct dentry *dentry;
102 	const struct cred *cred;
103 	struct rpc_cred __rcu *ll_cred;	/* low-level cred - use to check for expiry */
104 	struct nfs4_state *state;
105 	fmode_t mode;
106 
107 	int error;
108 	unsigned long flags;
109 #define NFS_CONTEXT_BAD			(2)
110 #define NFS_CONTEXT_UNLOCK	(3)
111 #define NFS_CONTEXT_FILE_OPEN		(4)
112 #define NFS_CONTEXT_WRITE_SYNC		(5)
113 
114 	struct nfs4_threshold	*mdsthreshold;
115 	struct list_head list;
116 	struct rcu_head	rcu_head;
117 	struct nfs_file_localio nfl;
118 };
119 
120 struct nfs_open_dir_context {
121 	struct list_head list;
122 	atomic_t cache_hits;
123 	atomic_t cache_misses;
124 	unsigned long attr_gencount;
125 	__be32	verf[NFS_DIR_VERIFIER_SIZE];
126 	__u64 dir_cookie;
127 	__u64 last_cookie;
128 	pgoff_t page_index;
129 	unsigned int dtsize;
130 	bool force_clear;
131 	bool eof;
132 	struct rcu_head rcu_head;
133 };
134 
135 /*
136  * NFSv4 delegation
137  */
138 struct nfs_delegation;
139 
140 struct posix_acl;
141 
142 struct nfs4_xattr_cache;
143 
144 /*
145  * nfs fs inode data in memory
146  */
147 struct nfs_inode {
148 	/*
149 	 * The 64bit 'inode number'
150 	 */
151 	__u64 fileid;
152 
153 	/*
154 	 * NFS file handle
155 	 */
156 	struct nfs_fh		fh;
157 
158 	/*
159 	 * Various flags
160 	 */
161 	unsigned long		flags;			/* atomic bit ops */
162 	unsigned long		cache_validity;		/* bit mask */
163 
164 	/*
165 	 * NFS Attributes not included in struct inode
166 	 */
167 
168 	struct timespec64	btime;
169 
170 	/*
171 	 * read_cache_jiffies is when we started read-caching this inode.
172 	 * attrtimeo is for how long the cached information is assumed
173 	 * to be valid. A successful attribute revalidation doubles
174 	 * attrtimeo (up to acregmax/acdirmax), a failure resets it to
175 	 * acregmin/acdirmin.
176 	 *
177 	 * We need to revalidate the cached attrs for this inode if
178 	 *
179 	 *	jiffies - read_cache_jiffies >= attrtimeo
180 	 *
181 	 * Please note the comparison is greater than or equal
182 	 * so that zero timeout values can be specified.
183 	 */
184 	unsigned long		read_cache_jiffies;
185 	unsigned long		attrtimeo;
186 	unsigned long		attrtimeo_timestamp;
187 
188 	unsigned long		attr_gencount;
189 
190 	struct rb_root		access_cache;
191 	struct list_head	access_cache_entry_lru;
192 	struct list_head	access_cache_inode_lru;
193 
194 	union {
195 		/* Directory */
196 		struct {
197 			/* "Generation counter" for the attribute cache.
198 			 * This is bumped whenever we update the metadata
199 			 * on the server.
200 			 */
201 			unsigned long	cache_change_attribute;
202 			/*
203 			 * This is the cookie verifier used for NFSv3 readdir
204 			 * operations
205 			 */
206 			__be32		cookieverf[NFS_DIR_VERIFIER_SIZE];
207 			/* Readers: in-flight sillydelete RPC calls */
208 			/* Writers: rmdir */
209 			struct rw_semaphore	rmdir_sem;
210 		};
211 		/* Regular file */
212 		struct {
213 			atomic_long_t	nrequests;
214 			atomic_long_t	redirtied_pages;
215 			struct nfs_mds_commit_info commit_info;
216 			struct mutex	commit_mutex;
217 		};
218 	};
219 
220 	/* Open contexts for shared mmap writes */
221 	struct list_head	open_files;
222 
223 	/* Keep track of out-of-order replies.
224 	 * The ooo array contains start/end pairs of
225 	 * numbers from the changeid sequence when
226 	 * the inode's iversion has been updated.
227 	 * It also contains end/start pair (i.e. reverse order)
228 	 * of sections of the changeid sequence that have
229 	 * been seen in replies from the server.
230 	 * Normally these should match and when both
231 	 * A:B and B:A are found in ooo, they are both removed.
232 	 * And if a reply with A:B causes an iversion update
233 	 * of A:B, then neither are added.
234 	 * When a reply has pre_change that doesn't match
235 	 * iversion, then the changeid pair and any consequent
236 	 * change in iversion ARE added.  Later replies
237 	 * might fill in the gaps, or possibly a gap is caused
238 	 * by a change from another client.
239 	 * When a file or directory is opened, if the ooo table
240 	 * is not empty, then we assume the gaps were due to
241 	 * another client and we invalidate the cached data.
242 	 *
243 	 * We can only track a limited number of concurrent gaps.
244 	 * Currently that limit is 16.
245 	 * We allocate the table on demand.  If there is insufficient
246 	 * memory, then we probably cannot cache the file anyway
247 	 * so there is no loss.
248 	 */
249 	struct {
250 		int cnt;
251 		struct {
252 			u64 start, end;
253 		} gap[16];
254 	} *ooo;
255 
256 #if IS_ENABLED(CONFIG_NFS_V4)
257 	struct nfs4_cached_acl	*nfs4_acl;
258         /* NFSv4 state */
259 	struct list_head	open_states;
260 	struct nfs_delegation __rcu *delegation;
261 	struct rw_semaphore	rwsem;
262 
263 	/* pNFS layout information */
264 	struct pnfs_layout_hdr *layout;
265 #endif /* CONFIG_NFS_V4*/
266 	/* how many bytes have been written/read and how many bytes queued up */
267 	__u64 write_io;
268 	__u64 read_io;
269 #ifdef CONFIG_NFS_V4_2
270 	struct nfs4_xattr_cache *xattr_cache;
271 #endif
272 	union {
273 		struct inode		vfs_inode;
274 #ifdef CONFIG_NFS_FSCACHE
275 		struct netfs_inode	netfs; /* netfs context and VFS inode */
276 #endif
277 	};
278 };
279 
280 struct nfs4_copy_state {
281 	struct list_head	copies;
282 	struct list_head	src_copies;
283 	nfs4_stateid		stateid;
284 	struct completion	completion;
285 	uint64_t		count;
286 	struct nfs_writeverf	verf;
287 	int			error;
288 	int			flags;
289 	struct nfs4_state	*parent_src_state;
290 	struct nfs4_state	*parent_dst_state;
291 };
292 
293 /*
294  * Access bit flags
295  */
296 #define NFS_ACCESS_READ        0x0001
297 #define NFS_ACCESS_LOOKUP      0x0002
298 #define NFS_ACCESS_MODIFY      0x0004
299 #define NFS_ACCESS_EXTEND      0x0008
300 #define NFS_ACCESS_DELETE      0x0010
301 #define NFS_ACCESS_EXECUTE     0x0020
302 #define NFS_ACCESS_XAREAD      0x0040
303 #define NFS_ACCESS_XAWRITE     0x0080
304 #define NFS_ACCESS_XALIST      0x0100
305 
306 /*
307  * Cache validity bit flags
308  */
309 #define NFS_INO_INVALID_DATA	BIT(1)		/* cached data is invalid */
310 #define NFS_INO_INVALID_ATIME	BIT(2)		/* cached atime is invalid */
311 #define NFS_INO_INVALID_ACCESS	BIT(3)		/* cached access cred invalid */
312 #define NFS_INO_INVALID_ACL	BIT(4)		/* cached acls are invalid */
313 #define NFS_INO_REVAL_FORCED	BIT(6)		/* force revalidation ignoring a delegation */
314 #define NFS_INO_INVALID_LABEL	BIT(7)		/* cached label is invalid */
315 #define NFS_INO_INVALID_CHANGE	BIT(8)		/* cached change is invalid */
316 #define NFS_INO_INVALID_CTIME	BIT(9)		/* cached ctime is invalid */
317 #define NFS_INO_INVALID_MTIME	BIT(10)		/* cached mtime is invalid */
318 #define NFS_INO_INVALID_SIZE	BIT(11)		/* cached size is invalid */
319 #define NFS_INO_INVALID_OTHER	BIT(12)		/* other attrs are invalid */
320 #define NFS_INO_DATA_INVAL_DEFER	\
321 				BIT(13)		/* Deferred cache invalidation */
322 #define NFS_INO_INVALID_BLOCKS	BIT(14)         /* cached blocks are invalid */
323 #define NFS_INO_INVALID_XATTR	BIT(15)		/* xattrs are invalid */
324 #define NFS_INO_INVALID_NLINK	BIT(16)		/* cached nlinks is invalid */
325 #define NFS_INO_INVALID_MODE	BIT(17)		/* cached mode is invalid */
326 #define NFS_INO_INVALID_BTIME	BIT(18)		/* cached btime is invalid */
327 
328 #define NFS_INO_INVALID_ATTR	(NFS_INO_INVALID_CHANGE \
329 		| NFS_INO_INVALID_CTIME \
330 		| NFS_INO_INVALID_MTIME \
331 		| NFS_INO_INVALID_BTIME \
332 		| NFS_INO_INVALID_SIZE \
333 		| NFS_INO_INVALID_NLINK \
334 		| NFS_INO_INVALID_MODE \
335 		| NFS_INO_INVALID_OTHER)	/* inode metadata is invalid */
336 
337 /*
338  * Bit offsets in flags field
339  */
340 #define NFS_INO_STALE		(1)		/* possible stale inode */
341 #define NFS_INO_ACL_LRU_SET	(2)		/* Inode is on the LRU list */
342 #define NFS_INO_INVALIDATING	(3)		/* inode is being invalidated */
343 #define NFS_INO_PRESERVE_UNLINKED (4)		/* preserve file if removed while open */
344 #define NFS_INO_LAYOUTCOMMIT	(9)		/* layoutcommit required */
345 #define NFS_INO_LAYOUTCOMMITTING (10)		/* layoutcommit inflight */
346 #define NFS_INO_LAYOUTSTATS	(11)		/* layoutstats inflight */
347 #define NFS_INO_ODIRECT		(12)		/* I/O setting is O_DIRECT */
348 #define NFS_INO_REQ_DIR_DELEG	(13)		/* Request a directory delegation */
349 
NFS_I(const struct inode * inode)350 static inline struct nfs_inode *NFS_I(const struct inode *inode)
351 {
352 	return container_of(inode, struct nfs_inode, vfs_inode);
353 }
354 
NFS_SB(const struct super_block * s)355 static inline struct nfs_server *NFS_SB(const struct super_block *s)
356 {
357 	return (struct nfs_server *)(s->s_fs_info);
358 }
359 
NFS_FH(const struct inode * inode)360 static inline struct nfs_fh *NFS_FH(const struct inode *inode)
361 {
362 	return &NFS_I(inode)->fh;
363 }
364 
NFS_SERVER(const struct inode * inode)365 static inline struct nfs_server *NFS_SERVER(const struct inode *inode)
366 {
367 	return NFS_SB(inode->i_sb);
368 }
369 
NFS_CLIENT(const struct inode * inode)370 static inline struct rpc_clnt *NFS_CLIENT(const struct inode *inode)
371 {
372 	return NFS_SERVER(inode)->client;
373 }
374 
NFS_PROTO(const struct inode * inode)375 static inline const struct nfs_rpc_ops *NFS_PROTO(const struct inode *inode)
376 {
377 	return NFS_SERVER(inode)->nfs_client->rpc_ops;
378 }
379 
NFS_MINATTRTIMEO(const struct inode * inode)380 static inline unsigned NFS_MINATTRTIMEO(const struct inode *inode)
381 {
382 	struct nfs_server *nfss = NFS_SERVER(inode);
383 	return S_ISDIR(inode->i_mode) ? nfss->acdirmin : nfss->acregmin;
384 }
385 
NFS_MAXATTRTIMEO(const struct inode * inode)386 static inline unsigned NFS_MAXATTRTIMEO(const struct inode *inode)
387 {
388 	struct nfs_server *nfss = NFS_SERVER(inode);
389 	return S_ISDIR(inode->i_mode) ? nfss->acdirmax : nfss->acregmax;
390 }
391 
NFS_STALE(const struct inode * inode)392 static inline int NFS_STALE(const struct inode *inode)
393 {
394 	return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
395 }
396 
NFS_FILEID(const struct inode * inode)397 static inline __u64 NFS_FILEID(const struct inode *inode)
398 {
399 	return NFS_I(inode)->fileid;
400 }
401 
set_nfs_fileid(struct inode * inode,__u64 fileid)402 static inline void set_nfs_fileid(struct inode *inode, __u64 fileid)
403 {
404 	NFS_I(inode)->fileid = fileid;
405 }
406 
nfs_mark_for_revalidate(struct inode * inode)407 static inline void nfs_mark_for_revalidate(struct inode *inode)
408 {
409 	struct nfs_inode *nfsi = NFS_I(inode);
410 
411 	spin_lock(&inode->i_lock);
412 	nfsi->cache_validity |= NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL |
413 				NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_CTIME |
414 				NFS_INO_INVALID_SIZE;
415 	if (S_ISDIR(inode->i_mode))
416 		nfsi->cache_validity |= NFS_INO_INVALID_DATA;
417 	spin_unlock(&inode->i_lock);
418 }
419 
nfs_server_capable(const struct inode * inode,int cap)420 static inline int nfs_server_capable(const struct inode *inode, int cap)
421 {
422 	return NFS_SERVER(inode)->caps & cap;
423 }
424 
425 /**
426  * nfs_save_change_attribute - Returns the inode attribute change cookie
427  * @dir - pointer to parent directory inode
428  * The "cache change attribute" is updated when we need to revalidate
429  * our dentry cache after a directory was seen to change on the server.
430  */
nfs_save_change_attribute(struct inode * dir)431 static inline unsigned long nfs_save_change_attribute(struct inode *dir)
432 {
433 	return NFS_I(dir)->cache_change_attribute;
434 }
435 
436 /*
437  * linux/fs/nfs/inode.c
438  */
439 extern int nfs_sync_mapping(struct address_space *mapping);
440 extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
441 extern void nfs_zap_caches(struct inode *);
442 extern void nfs_set_inode_stale(struct inode *inode);
443 extern void nfs_invalidate_atime(struct inode *);
444 extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
445 				struct nfs_fattr *);
446 struct inode *nfs_ilookup(struct super_block *sb, struct nfs_fattr *, struct nfs_fh *);
447 extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
448 extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
449 extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
450 extern int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr);
451 extern int nfs_getattr(struct mnt_idmap *, const struct path *,
452 		       struct kstat *, u32, unsigned int);
453 extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *, const struct cred *);
454 extern void nfs_access_set_mask(struct nfs_access_entry *, u32);
455 extern int nfs_permission(struct mnt_idmap *, struct inode *, int);
456 extern int nfs_open(struct inode *, struct file *);
457 extern int nfs_attribute_cache_expired(struct inode *inode);
458 extern int nfs_revalidate_inode(struct inode *inode, unsigned long flags);
459 extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
460 extern int nfs_clear_invalid_mapping(struct address_space *mapping);
461 extern bool nfs_mapping_need_revalidate_inode(struct inode *inode);
462 extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
463 extern int nfs_revalidate_mapping_rcu(struct inode *inode);
464 extern int nfs_setattr(struct mnt_idmap *, struct dentry *, struct iattr *);
465 extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr, struct nfs_fattr *);
466 extern void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr);
467 extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
468 extern void put_nfs_open_context(struct nfs_open_context *ctx);
469 extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, const struct cred *cred, fmode_t mode);
470 extern struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode, struct file *filp);
471 extern void nfs_inode_attach_open_context(struct nfs_open_context *ctx);
472 extern void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx);
473 extern void nfs_file_clear_open_context(struct file *flip);
474 extern struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx);
475 extern void nfs_put_lock_context(struct nfs_lock_context *l_ctx);
476 extern u64 nfs_compat_user_ino64(u64 fileid);
477 extern void nfs_fattr_init(struct nfs_fattr *fattr);
478 extern void nfs_fattr_set_barrier(struct nfs_fattr *fattr);
479 extern unsigned long nfs_inc_attr_generation_counter(void);
480 
481 extern struct nfs_fattr *nfs_alloc_fattr(void);
482 extern struct nfs_fattr *nfs_alloc_fattr_with_label(struct nfs_server *server);
483 
nfs4_label_free(struct nfs4_label * label)484 static inline void nfs4_label_free(struct nfs4_label *label)
485 {
486 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
487 	if (label) {
488 		kfree(label->label);
489 		kfree(label);
490 	}
491 #endif
492 }
493 
nfs_free_fattr(const struct nfs_fattr * fattr)494 static inline void nfs_free_fattr(const struct nfs_fattr *fattr)
495 {
496 	if (fattr)
497 		nfs4_label_free(fattr->label);
498 	kfree(fattr);
499 }
500 
501 extern struct nfs_fh *nfs_alloc_fhandle(void);
502 
nfs_free_fhandle(const struct nfs_fh * fh)503 static inline void nfs_free_fhandle(const struct nfs_fh *fh)
504 {
505 	kfree(fh);
506 }
507 
508 #ifdef NFS_DEBUG
509 extern u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh);
nfs_display_fhandle_hash(const struct nfs_fh * fh)510 static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
511 {
512 	return _nfs_display_fhandle_hash(fh);
513 }
514 extern void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption);
515 #define nfs_display_fhandle(fh, caption)			\
516 	do {							\
517 		if (unlikely(nfs_debug & NFSDBG_FACILITY))	\
518 			_nfs_display_fhandle(fh, caption);	\
519 	} while (0)
520 #else
nfs_display_fhandle_hash(const struct nfs_fh * fh)521 static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
522 {
523 	return 0;
524 }
nfs_display_fhandle(const struct nfs_fh * fh,const char * caption)525 static inline void nfs_display_fhandle(const struct nfs_fh *fh,
526 				       const char *caption)
527 {
528 }
529 #endif
530 
531 /*
532  * linux/fs/nfs/nfsroot.c
533  */
534 extern int  nfs_root_data(char **root_device, char **root_data); /*__init*/
535 /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
536 extern __be32 root_nfs_parse_addr(char *name); /*__init*/
537 
538 /*
539  * linux/fs/nfs/file.c
540  */
541 extern const struct file_operations nfs_file_operations;
542 #if IS_ENABLED(CONFIG_NFS_V4)
543 extern const struct file_operations nfs4_file_operations;
544 #endif /* CONFIG_NFS_V4 */
545 extern const struct address_space_operations nfs_file_aops;
546 extern const struct address_space_operations nfs_dir_aops;
547 
nfs_file_open_context(struct file * filp)548 static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
549 {
550 	return filp->private_data;
551 }
552 
nfs_file_cred(struct file * file)553 static inline const struct cred *nfs_file_cred(struct file *file)
554 {
555 	if (file != NULL) {
556 		struct nfs_open_context *ctx =
557 			nfs_file_open_context(file);
558 		if (ctx)
559 			return ctx->cred;
560 	}
561 	return NULL;
562 }
563 
564 /*
565  * linux/fs/nfs/direct.c
566  */
567 int nfs_swap_rw(struct kiocb *iocb, struct iov_iter *iter);
568 ssize_t nfs_file_direct_read(struct kiocb *iocb,
569 			     struct iov_iter *iter, bool swap);
570 ssize_t nfs_file_direct_write(struct kiocb *iocb,
571 			      struct iov_iter *iter, bool swap);
572 
573 /*
574  * linux/fs/nfs/dir.c
575  */
576 extern const struct file_operations nfs_dir_operations;
577 extern const struct dentry_operations nfs_dentry_operations;
578 
579 extern void nfs_force_lookup_revalidate(struct inode *dir);
580 extern void nfs_set_verifier(struct dentry * dentry, unsigned long verf);
581 #if IS_ENABLED(CONFIG_NFS_V4)
582 extern void nfs_clear_verifier_delegated(struct inode *inode);
583 #endif /* IS_ENABLED(CONFIG_NFS_V4) */
584 extern struct dentry *nfs_add_or_obtain(struct dentry *dentry,
585 			struct nfs_fh *fh, struct nfs_fattr *fattr);
586 extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh,
587 			struct nfs_fattr *fattr);
588 extern int nfs_may_open(struct inode *inode, const struct cred *cred, int openflags);
589 extern void nfs_access_zap_cache(struct inode *inode);
590 extern int nfs_access_get_cached(struct inode *inode, const struct cred *cred,
591 				 u32 *mask, bool may_block);
592 extern int nfs_atomic_open_v23(struct inode *dir, struct dentry *dentry,
593 			       struct file *file, unsigned int open_flags,
594 			       umode_t mode);
595 
596 /*
597  * linux/fs/nfs/symlink.c
598  */
599 extern const struct inode_operations nfs_symlink_inode_operations;
600 
601 /*
602  * linux/fs/nfs/sysctl.c
603  */
604 #ifdef CONFIG_SYSCTL
605 extern int nfs_register_sysctl(void);
606 extern void nfs_unregister_sysctl(void);
607 #else
608 #define nfs_register_sysctl() 0
609 #define nfs_unregister_sysctl() do { } while(0)
610 #endif
611 
612 /*
613  * linux/fs/nfs/namespace.c
614  */
615 extern const struct inode_operations nfs_mountpoint_inode_operations;
616 extern const struct inode_operations nfs_referral_inode_operations;
617 extern int nfs_mountpoint_expiry_timeout;
618 extern void nfs_release_automount_timer(void);
619 
620 /*
621  * linux/fs/nfs/unlink.c
622  */
623 extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
624 
625 /*
626  * linux/fs/nfs/write.c
627  */
628 extern int  nfs_congestion_kb;
629 extern int  nfs_writepages(struct address_space *, struct writeback_control *);
630 extern int  nfs_flush_incompatible(struct file *file, struct folio *folio);
631 extern int  nfs_update_folio(struct file *file, struct folio *folio,
632 			     unsigned int offset, unsigned int count);
633 
634 /*
635  * Try to write back everything synchronously (but check the
636  * return value!)
637  */
638 extern int nfs_sync_inode(struct inode *inode);
639 extern int nfs_wb_all(struct inode *inode);
640 extern int nfs_wb_folio(struct inode *inode, struct folio *folio);
641 extern int nfs_wb_folio_reclaim(struct inode *inode, struct folio *folio);
642 int nfs_wb_folio_cancel(struct inode *inode, struct folio *folio);
643 extern int  nfs_commit_inode(struct inode *, int);
644 extern struct nfs_commit_data *nfs_commitdata_alloc(void);
645 extern void nfs_commit_free(struct nfs_commit_data *data);
646 void nfs_commit_begin(struct nfs_mds_commit_info *cinfo);
647 bool nfs_commit_end(struct nfs_mds_commit_info *cinfo);
648 
nfs_have_writebacks(const struct inode * inode)649 static inline bool nfs_have_writebacks(const struct inode *inode)
650 {
651 	if (S_ISREG(inode->i_mode))
652 		return atomic_long_read(&NFS_I(inode)->nrequests) != 0;
653 	return false;
654 }
655 
656 /*
657  * linux/fs/nfs/read.c
658  */
659 int  nfs_read_folio(struct file *, struct folio *);
660 void nfs_readahead(struct readahead_control *);
661 
662 /*
663  * inline functions
664  */
665 
nfs_size_to_loff_t(__u64 size)666 static inline loff_t nfs_size_to_loff_t(__u64 size)
667 {
668 	return min_t(u64, size, OFFSET_MAX);
669 }
670 
671 static inline ino_t
nfs_fileid_to_ino_t(u64 fileid)672 nfs_fileid_to_ino_t(u64 fileid)
673 {
674 	ino_t ino = (ino_t) fileid;
675 	if (sizeof(ino_t) < sizeof(u64))
676 		ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
677 	return ino;
678 }
679 
nfs_ooo_clear(struct nfs_inode * nfsi)680 static inline void nfs_ooo_clear(struct nfs_inode *nfsi)
681 {
682 	nfsi->cache_validity &= ~NFS_INO_DATA_INVAL_DEFER;
683 	kfree(nfsi->ooo);
684 	nfsi->ooo = NULL;
685 }
686 
nfs_ooo_test(struct nfs_inode * nfsi)687 static inline bool nfs_ooo_test(struct nfs_inode *nfsi)
688 {
689 	return (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER) ||
690 		(nfsi->ooo && nfsi->ooo->cnt > 0);
691 
692 }
693 
694 #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
695 
696 /* We need to block new opens while a file is being unlinked.
697  * If it is opened *before* we decide to unlink, we will silly-rename
698  * instead. If it is opened *after*, then we need to create or will fail.
699  * If we allow the two to race, we could end up with a file that is open
700  * but deleted on the server resulting in ESTALE.
701  * So use ->d_fsdata to record when the unlink is happening
702  * and block dentry revalidation while it is set.
703  */
704 #define NFS_FSDATA_BLOCKED ((void*)1)
705 
706 # undef ifdebug
707 # ifdef NFS_DEBUG
708 #  define ifdebug(fac)		if (unlikely(nfs_debug & NFSDBG_##fac))
709 #  define NFS_IFDEBUG(x)	x
710 # else
711 #  define ifdebug(fac)		if (0)
712 #  define NFS_IFDEBUG(x)
713 # endif
714 #endif
715