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