xref: /openbmc/linux/include/linux/nfs_fs.h (revision 61f4d204)
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 nfs4_state;
81 struct nfs_open_context {
82 	struct nfs_lock_context lock_context;
83 	fl_owner_t flock_owner;
84 	struct dentry *dentry;
85 	const struct cred *cred;
86 	struct rpc_cred __rcu *ll_cred;	/* low-level cred - use to check for expiry */
87 	struct nfs4_state *state;
88 	fmode_t mode;
89 
90 	unsigned long flags;
91 #define NFS_CONTEXT_BAD			(2)
92 #define NFS_CONTEXT_UNLOCK	(3)
93 #define NFS_CONTEXT_FILE_OPEN		(4)
94 	int error;
95 
96 	struct list_head list;
97 	struct nfs4_threshold	*mdsthreshold;
98 	struct rcu_head	rcu_head;
99 };
100 
101 struct nfs_open_dir_context {
102 	struct list_head list;
103 	atomic_t cache_hits;
104 	atomic_t cache_misses;
105 	unsigned long attr_gencount;
106 	__be32	verf[NFS_DIR_VERIFIER_SIZE];
107 	__u64 dir_cookie;
108 	__u64 last_cookie;
109 	pgoff_t page_index;
110 	unsigned int dtsize;
111 	bool force_clear;
112 	bool eof;
113 	struct rcu_head rcu_head;
114 };
115 
116 /*
117  * NFSv4 delegation
118  */
119 struct nfs_delegation;
120 
121 struct posix_acl;
122 
123 struct nfs4_xattr_cache;
124 
125 /*
126  * nfs fs inode data in memory
127  */
128 struct nfs_inode {
129 	/*
130 	 * The 64bit 'inode number'
131 	 */
132 	__u64 fileid;
133 
134 	/*
135 	 * NFS file handle
136 	 */
137 	struct nfs_fh		fh;
138 
139 	/*
140 	 * Various flags
141 	 */
142 	unsigned long		flags;			/* atomic bit ops */
143 	unsigned long		cache_validity;		/* bit mask */
144 
145 	/*
146 	 * read_cache_jiffies is when we started read-caching this inode.
147 	 * attrtimeo is for how long the cached information is assumed
148 	 * to be valid. A successful attribute revalidation doubles
149 	 * attrtimeo (up to acregmax/acdirmax), a failure resets it to
150 	 * acregmin/acdirmin.
151 	 *
152 	 * We need to revalidate the cached attrs for this inode if
153 	 *
154 	 *	jiffies - read_cache_jiffies >= attrtimeo
155 	 *
156 	 * Please note the comparison is greater than or equal
157 	 * so that zero timeout values can be specified.
158 	 */
159 	unsigned long		read_cache_jiffies;
160 	unsigned long		attrtimeo;
161 	unsigned long		attrtimeo_timestamp;
162 
163 	unsigned long		attr_gencount;
164 
165 	struct rb_root		access_cache;
166 	struct list_head	access_cache_entry_lru;
167 	struct list_head	access_cache_inode_lru;
168 
169 	union {
170 		/* Directory */
171 		struct {
172 			/* "Generation counter" for the attribute cache.
173 			 * This is bumped whenever we update the metadata
174 			 * on the server.
175 			 */
176 			unsigned long	cache_change_attribute;
177 			/*
178 			 * This is the cookie verifier used for NFSv3 readdir
179 			 * operations
180 			 */
181 			__be32		cookieverf[NFS_DIR_VERIFIER_SIZE];
182 			/* Readers: in-flight sillydelete RPC calls */
183 			/* Writers: rmdir */
184 			struct rw_semaphore	rmdir_sem;
185 		};
186 		/* Regular file */
187 		struct {
188 			atomic_long_t	nrequests;
189 			atomic_long_t	redirtied_pages;
190 			struct nfs_mds_commit_info commit_info;
191 			struct mutex	commit_mutex;
192 		};
193 	};
194 
195 	/* Open contexts for shared mmap writes */
196 	struct list_head	open_files;
197 
198 	/* Keep track of out-of-order replies.
199 	 * The ooo array contains start/end pairs of
200 	 * numbers from the changeid sequence when
201 	 * the inode's iversion has been updated.
202 	 * It also contains end/start pair (i.e. reverse order)
203 	 * of sections of the changeid sequence that have
204 	 * been seen in replies from the server.
205 	 * Normally these should match and when both
206 	 * A:B and B:A are found in ooo, they are both removed.
207 	 * And if a reply with A:B causes an iversion update
208 	 * of A:B, then neither are added.
209 	 * When a reply has pre_change that doesn't match
210 	 * iversion, then the changeid pair and any consequent
211 	 * change in iversion ARE added.  Later replies
212 	 * might fill in the gaps, or possibly a gap is caused
213 	 * by a change from another client.
214 	 * When a file or directory is opened, if the ooo table
215 	 * is not empty, then we assume the gaps were due to
216 	 * another client and we invalidate the cached data.
217 	 *
218 	 * We can only track a limited number of concurrent gaps.
219 	 * Currently that limit is 16.
220 	 * We allocate the table on demand.  If there is insufficient
221 	 * memory, then we probably cannot cache the file anyway
222 	 * so there is no loss.
223 	 */
224 	struct {
225 		int cnt;
226 		struct {
227 			u64 start, end;
228 		} gap[16];
229 	} *ooo;
230 
231 #if IS_ENABLED(CONFIG_NFS_V4)
232 	struct nfs4_cached_acl	*nfs4_acl;
233         /* NFSv4 state */
234 	struct list_head	open_states;
235 	struct nfs_delegation __rcu *delegation;
236 	struct rw_semaphore	rwsem;
237 
238 	/* pNFS layout information */
239 	struct pnfs_layout_hdr *layout;
240 #endif /* CONFIG_NFS_V4*/
241 	/* how many bytes have been written/read and how many bytes queued up */
242 	__u64 write_io;
243 	__u64 read_io;
244 #ifdef CONFIG_NFS_V4_2
245 	struct nfs4_xattr_cache *xattr_cache;
246 #endif
247 	union {
248 		struct inode		vfs_inode;
249 #ifdef CONFIG_NFS_FSCACHE
250 		struct netfs_inode	netfs; /* netfs context and VFS inode */
251 #endif
252 	};
253 };
254 
255 struct nfs4_copy_state {
256 	struct list_head	copies;
257 	struct list_head	src_copies;
258 	nfs4_stateid		stateid;
259 	struct completion	completion;
260 	uint64_t		count;
261 	struct nfs_writeverf	verf;
262 	int			error;
263 	int			flags;
264 	struct nfs4_state	*parent_src_state;
265 	struct nfs4_state	*parent_dst_state;
266 };
267 
268 /*
269  * Access bit flags
270  */
271 #define NFS_ACCESS_READ        0x0001
272 #define NFS_ACCESS_LOOKUP      0x0002
273 #define NFS_ACCESS_MODIFY      0x0004
274 #define NFS_ACCESS_EXTEND      0x0008
275 #define NFS_ACCESS_DELETE      0x0010
276 #define NFS_ACCESS_EXECUTE     0x0020
277 #define NFS_ACCESS_XAREAD      0x0040
278 #define NFS_ACCESS_XAWRITE     0x0080
279 #define NFS_ACCESS_XALIST      0x0100
280 
281 /*
282  * Cache validity bit flags
283  */
284 #define NFS_INO_INVALID_DATA	BIT(1)		/* cached data is invalid */
285 #define NFS_INO_INVALID_ATIME	BIT(2)		/* cached atime is invalid */
286 #define NFS_INO_INVALID_ACCESS	BIT(3)		/* cached access cred invalid */
287 #define NFS_INO_INVALID_ACL	BIT(4)		/* cached acls are invalid */
288 #define NFS_INO_REVAL_FORCED	BIT(6)		/* force revalidation ignoring a delegation */
289 #define NFS_INO_INVALID_LABEL	BIT(7)		/* cached label is invalid */
290 #define NFS_INO_INVALID_CHANGE	BIT(8)		/* cached change is invalid */
291 #define NFS_INO_INVALID_CTIME	BIT(9)		/* cached ctime is invalid */
292 #define NFS_INO_INVALID_MTIME	BIT(10)		/* cached mtime is invalid */
293 #define NFS_INO_INVALID_SIZE	BIT(11)		/* cached size is invalid */
294 #define NFS_INO_INVALID_OTHER	BIT(12)		/* other attrs are invalid */
295 #define NFS_INO_DATA_INVAL_DEFER	\
296 				BIT(13)		/* Deferred cache invalidation */
297 #define NFS_INO_INVALID_BLOCKS	BIT(14)         /* cached blocks are invalid */
298 #define NFS_INO_INVALID_XATTR	BIT(15)		/* xattrs are invalid */
299 #define NFS_INO_INVALID_NLINK	BIT(16)		/* cached nlinks is invalid */
300 #define NFS_INO_INVALID_MODE	BIT(17)		/* cached mode is invalid */
301 
302 #define NFS_INO_INVALID_ATTR	(NFS_INO_INVALID_CHANGE \
303 		| NFS_INO_INVALID_CTIME \
304 		| NFS_INO_INVALID_MTIME \
305 		| NFS_INO_INVALID_SIZE \
306 		| NFS_INO_INVALID_NLINK \
307 		| NFS_INO_INVALID_MODE \
308 		| NFS_INO_INVALID_OTHER)	/* inode metadata is invalid */
309 
310 /*
311  * Bit offsets in flags field
312  */
313 #define NFS_INO_STALE		(1)		/* possible stale inode */
314 #define NFS_INO_ACL_LRU_SET	(2)		/* Inode is on the LRU list */
315 #define NFS_INO_INVALIDATING	(3)		/* inode is being invalidated */
316 #define NFS_INO_PRESERVE_UNLINKED (4)		/* preserve file if removed while open */
317 #define NFS_INO_LAYOUTCOMMIT	(9)		/* layoutcommit required */
318 #define NFS_INO_LAYOUTCOMMITTING (10)		/* layoutcommit inflight */
319 #define NFS_INO_LAYOUTSTATS	(11)		/* layoutstats inflight */
320 #define NFS_INO_ODIRECT		(12)		/* I/O setting is O_DIRECT */
321 
322 static inline struct nfs_inode *NFS_I(const struct inode *inode)
323 {
324 	return container_of(inode, struct nfs_inode, vfs_inode);
325 }
326 
327 static inline struct nfs_server *NFS_SB(const struct super_block *s)
328 {
329 	return (struct nfs_server *)(s->s_fs_info);
330 }
331 
332 static inline struct nfs_fh *NFS_FH(const struct inode *inode)
333 {
334 	return &NFS_I(inode)->fh;
335 }
336 
337 static inline struct nfs_server *NFS_SERVER(const struct inode *inode)
338 {
339 	return NFS_SB(inode->i_sb);
340 }
341 
342 static inline struct rpc_clnt *NFS_CLIENT(const struct inode *inode)
343 {
344 	return NFS_SERVER(inode)->client;
345 }
346 
347 static inline const struct nfs_rpc_ops *NFS_PROTO(const struct inode *inode)
348 {
349 	return NFS_SERVER(inode)->nfs_client->rpc_ops;
350 }
351 
352 static inline unsigned NFS_MINATTRTIMEO(const struct inode *inode)
353 {
354 	struct nfs_server *nfss = NFS_SERVER(inode);
355 	return S_ISDIR(inode->i_mode) ? nfss->acdirmin : nfss->acregmin;
356 }
357 
358 static inline unsigned NFS_MAXATTRTIMEO(const struct inode *inode)
359 {
360 	struct nfs_server *nfss = NFS_SERVER(inode);
361 	return S_ISDIR(inode->i_mode) ? nfss->acdirmax : nfss->acregmax;
362 }
363 
364 static inline int NFS_STALE(const struct inode *inode)
365 {
366 	return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
367 }
368 
369 static inline __u64 NFS_FILEID(const struct inode *inode)
370 {
371 	return NFS_I(inode)->fileid;
372 }
373 
374 static inline void set_nfs_fileid(struct inode *inode, __u64 fileid)
375 {
376 	NFS_I(inode)->fileid = fileid;
377 }
378 
379 static inline void nfs_mark_for_revalidate(struct inode *inode)
380 {
381 	struct nfs_inode *nfsi = NFS_I(inode);
382 
383 	spin_lock(&inode->i_lock);
384 	nfsi->cache_validity |= NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL |
385 				NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_CTIME |
386 				NFS_INO_INVALID_SIZE;
387 	if (S_ISDIR(inode->i_mode))
388 		nfsi->cache_validity |= NFS_INO_INVALID_DATA;
389 	spin_unlock(&inode->i_lock);
390 }
391 
392 static inline int nfs_server_capable(const struct inode *inode, int cap)
393 {
394 	return NFS_SERVER(inode)->caps & cap;
395 }
396 
397 /**
398  * nfs_save_change_attribute - Returns the inode attribute change cookie
399  * @dir - pointer to parent directory inode
400  * The "cache change attribute" is updated when we need to revalidate
401  * our dentry cache after a directory was seen to change on the server.
402  */
403 static inline unsigned long nfs_save_change_attribute(struct inode *dir)
404 {
405 	return NFS_I(dir)->cache_change_attribute;
406 }
407 
408 /*
409  * linux/fs/nfs/inode.c
410  */
411 extern int nfs_sync_mapping(struct address_space *mapping);
412 extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
413 extern void nfs_zap_caches(struct inode *);
414 extern void nfs_set_inode_stale(struct inode *inode);
415 extern void nfs_invalidate_atime(struct inode *);
416 extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
417 				struct nfs_fattr *);
418 struct inode *nfs_ilookup(struct super_block *sb, struct nfs_fattr *, struct nfs_fh *);
419 extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
420 extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
421 extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
422 extern int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr);
423 extern int nfs_getattr(struct mnt_idmap *, const struct path *,
424 		       struct kstat *, u32, unsigned int);
425 extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *, const struct cred *);
426 extern void nfs_access_set_mask(struct nfs_access_entry *, u32);
427 extern int nfs_permission(struct mnt_idmap *, struct inode *, int);
428 extern int nfs_open(struct inode *, struct file *);
429 extern int nfs_attribute_cache_expired(struct inode *inode);
430 extern int nfs_revalidate_inode(struct inode *inode, unsigned long flags);
431 extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
432 extern int nfs_clear_invalid_mapping(struct address_space *mapping);
433 extern bool nfs_mapping_need_revalidate_inode(struct inode *inode);
434 extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
435 extern int nfs_revalidate_mapping_rcu(struct inode *inode);
436 extern int nfs_setattr(struct mnt_idmap *, struct dentry *, struct iattr *);
437 extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr, struct nfs_fattr *);
438 extern void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr);
439 extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
440 extern void put_nfs_open_context(struct nfs_open_context *ctx);
441 extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, const struct cred *cred, fmode_t mode);
442 extern struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode, struct file *filp);
443 extern void nfs_inode_attach_open_context(struct nfs_open_context *ctx);
444 extern void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx);
445 extern void nfs_file_clear_open_context(struct file *flip);
446 extern struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx);
447 extern void nfs_put_lock_context(struct nfs_lock_context *l_ctx);
448 extern u64 nfs_compat_user_ino64(u64 fileid);
449 extern void nfs_fattr_init(struct nfs_fattr *fattr);
450 extern void nfs_fattr_set_barrier(struct nfs_fattr *fattr);
451 extern unsigned long nfs_inc_attr_generation_counter(void);
452 
453 extern struct nfs_fattr *nfs_alloc_fattr(void);
454 extern struct nfs_fattr *nfs_alloc_fattr_with_label(struct nfs_server *server);
455 
456 static inline void nfs4_label_free(struct nfs4_label *label)
457 {
458 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
459 	if (label) {
460 		kfree(label->label);
461 		kfree(label);
462 	}
463 #endif
464 }
465 
466 static inline void nfs_free_fattr(const struct nfs_fattr *fattr)
467 {
468 	if (fattr)
469 		nfs4_label_free(fattr->label);
470 	kfree(fattr);
471 }
472 
473 extern struct nfs_fh *nfs_alloc_fhandle(void);
474 
475 static inline void nfs_free_fhandle(const struct nfs_fh *fh)
476 {
477 	kfree(fh);
478 }
479 
480 #ifdef NFS_DEBUG
481 extern u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh);
482 static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
483 {
484 	return _nfs_display_fhandle_hash(fh);
485 }
486 extern void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption);
487 #define nfs_display_fhandle(fh, caption)			\
488 	do {							\
489 		if (unlikely(nfs_debug & NFSDBG_FACILITY))	\
490 			_nfs_display_fhandle(fh, caption);	\
491 	} while (0)
492 #else
493 static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
494 {
495 	return 0;
496 }
497 static inline void nfs_display_fhandle(const struct nfs_fh *fh,
498 				       const char *caption)
499 {
500 }
501 #endif
502 
503 /*
504  * linux/fs/nfs/nfsroot.c
505  */
506 extern int  nfs_root_data(char **root_device, char **root_data); /*__init*/
507 /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
508 extern __be32 root_nfs_parse_addr(char *name); /*__init*/
509 
510 /*
511  * linux/fs/nfs/file.c
512  */
513 extern const struct file_operations nfs_file_operations;
514 #if IS_ENABLED(CONFIG_NFS_V4)
515 extern const struct file_operations nfs4_file_operations;
516 #endif /* CONFIG_NFS_V4 */
517 extern const struct address_space_operations nfs_file_aops;
518 extern const struct address_space_operations nfs_dir_aops;
519 
520 static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
521 {
522 	return filp->private_data;
523 }
524 
525 static inline const struct cred *nfs_file_cred(struct file *file)
526 {
527 	if (file != NULL) {
528 		struct nfs_open_context *ctx =
529 			nfs_file_open_context(file);
530 		if (ctx)
531 			return ctx->cred;
532 	}
533 	return NULL;
534 }
535 
536 /*
537  * linux/fs/nfs/direct.c
538  */
539 int nfs_swap_rw(struct kiocb *iocb, struct iov_iter *iter);
540 ssize_t nfs_file_direct_read(struct kiocb *iocb,
541 			     struct iov_iter *iter, bool swap);
542 ssize_t nfs_file_direct_write(struct kiocb *iocb,
543 			      struct iov_iter *iter, bool swap);
544 
545 /*
546  * linux/fs/nfs/dir.c
547  */
548 extern const struct file_operations nfs_dir_operations;
549 extern const struct dentry_operations nfs_dentry_operations;
550 
551 extern void nfs_force_lookup_revalidate(struct inode *dir);
552 extern void nfs_set_verifier(struct dentry * dentry, unsigned long verf);
553 #if IS_ENABLED(CONFIG_NFS_V4)
554 extern void nfs_clear_verifier_delegated(struct inode *inode);
555 #endif /* IS_ENABLED(CONFIG_NFS_V4) */
556 extern struct dentry *nfs_add_or_obtain(struct dentry *dentry,
557 			struct nfs_fh *fh, struct nfs_fattr *fattr);
558 extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh,
559 			struct nfs_fattr *fattr);
560 extern int nfs_may_open(struct inode *inode, const struct cred *cred, int openflags);
561 extern void nfs_access_zap_cache(struct inode *inode);
562 extern int nfs_access_get_cached(struct inode *inode, const struct cred *cred,
563 				 u32 *mask, bool may_block);
564 
565 /*
566  * linux/fs/nfs/symlink.c
567  */
568 extern const struct inode_operations nfs_symlink_inode_operations;
569 
570 /*
571  * linux/fs/nfs/sysctl.c
572  */
573 #ifdef CONFIG_SYSCTL
574 extern int nfs_register_sysctl(void);
575 extern void nfs_unregister_sysctl(void);
576 #else
577 #define nfs_register_sysctl() 0
578 #define nfs_unregister_sysctl() do { } while(0)
579 #endif
580 
581 /*
582  * linux/fs/nfs/namespace.c
583  */
584 extern const struct inode_operations nfs_mountpoint_inode_operations;
585 extern const struct inode_operations nfs_referral_inode_operations;
586 extern int nfs_mountpoint_expiry_timeout;
587 extern void nfs_release_automount_timer(void);
588 
589 /*
590  * linux/fs/nfs/unlink.c
591  */
592 extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
593 
594 /*
595  * linux/fs/nfs/write.c
596  */
597 extern int  nfs_congestion_kb;
598 extern int  nfs_writepage(struct page *page, struct writeback_control *wbc);
599 extern int  nfs_writepages(struct address_space *, struct writeback_control *);
600 extern int  nfs_flush_incompatible(struct file *file, struct folio *folio);
601 extern int  nfs_update_folio(struct file *file, struct folio *folio,
602 			     unsigned int offset, unsigned int count);
603 
604 /*
605  * Try to write back everything synchronously (but check the
606  * return value!)
607  */
608 extern int nfs_sync_inode(struct inode *inode);
609 extern int nfs_wb_all(struct inode *inode);
610 extern int nfs_wb_folio(struct inode *inode, struct folio *folio);
611 int nfs_wb_folio_cancel(struct inode *inode, struct folio *folio);
612 extern int  nfs_commit_inode(struct inode *, int);
613 extern struct nfs_commit_data *nfs_commitdata_alloc(void);
614 extern void nfs_commit_free(struct nfs_commit_data *data);
615 bool nfs_commit_end(struct nfs_mds_commit_info *cinfo);
616 
617 static inline bool nfs_have_writebacks(const struct inode *inode)
618 {
619 	if (S_ISREG(inode->i_mode))
620 		return atomic_long_read(&NFS_I(inode)->nrequests) != 0;
621 	return false;
622 }
623 
624 /*
625  * linux/fs/nfs/read.c
626  */
627 int  nfs_read_folio(struct file *, struct folio *);
628 void nfs_readahead(struct readahead_control *);
629 
630 /*
631  * inline functions
632  */
633 
634 static inline loff_t nfs_size_to_loff_t(__u64 size)
635 {
636 	return min_t(u64, size, OFFSET_MAX);
637 }
638 
639 static inline ino_t
640 nfs_fileid_to_ino_t(u64 fileid)
641 {
642 	ino_t ino = (ino_t) fileid;
643 	if (sizeof(ino_t) < sizeof(u64))
644 		ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
645 	return ino;
646 }
647 
648 static inline void nfs_ooo_clear(struct nfs_inode *nfsi)
649 {
650 	nfsi->cache_validity &= ~NFS_INO_DATA_INVAL_DEFER;
651 	kfree(nfsi->ooo);
652 	nfsi->ooo = NULL;
653 }
654 
655 static inline bool nfs_ooo_test(struct nfs_inode *nfsi)
656 {
657 	return (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER) ||
658 		(nfsi->ooo && nfsi->ooo->cnt > 0);
659 
660 }
661 
662 #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
663 
664 /* We need to block new opens while a file is being unlinked.
665  * If it is opened *before* we decide to unlink, we will silly-rename
666  * instead. If it is opened *after*, then we need to create or will fail.
667  * If we allow the two to race, we could end up with a file that is open
668  * but deleted on the server resulting in ESTALE.
669  * So use ->d_fsdata to record when the unlink is happening
670  * and block dentry revalidation while it is set.
671  */
672 #define NFS_FSDATA_BLOCKED ((void*)1)
673 
674 # undef ifdebug
675 # ifdef NFS_DEBUG
676 #  define ifdebug(fac)		if (unlikely(nfs_debug & NFSDBG_##fac))
677 #  define NFS_IFDEBUG(x)	x
678 # else
679 #  define ifdebug(fac)		if (0)
680 #  define NFS_IFDEBUG(x)
681 # endif
682 #endif
683