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1 /*
2 * linux/include/linux/nfs_fs.h
3 *
4 * Copyright (C) 1992 Rick Sladkey
5 *
6 * OS-specific nfs filesystem definitions and declarations
7 */
8
9 #ifndef _LINUX_NFS_FS_H
10 #define _LINUX_NFS_FS_H
11
12 #include <linux/magic.h>
13
14 /* Default timeout values */
15 #define NFS_DEF_UDP_TIMEO (11)
16 #define NFS_DEF_UDP_RETRANS (3)
17 #define NFS_DEF_TCP_TIMEO (600)
18 #define NFS_DEF_TCP_RETRANS (2)
19
20 #define NFS_MAX_UDP_TIMEOUT (60*HZ)
21 #define NFS_MAX_TCP_TIMEOUT (600*HZ)
22
23 #define NFS_DEF_ACREGMIN (3)
24 #define NFS_DEF_ACREGMAX (60)
25 #define NFS_DEF_ACDIRMIN (30)
26 #define NFS_DEF_ACDIRMAX (60)
27
28 /*
29 * When flushing a cluster of dirty pages, there can be different
30 * strategies:
31 */
32 #define FLUSH_SYNC 1 /* file being synced, or contention */
33 #define FLUSH_STABLE 4 /* commit to stable storage */
34 #define FLUSH_LOWPRI 8 /* low priority background flush */
35 #define FLUSH_HIGHPRI 16 /* high priority memory reclaim flush */
36 #define FLUSH_COND_STABLE 32 /* conditional stable write - only stable
37 * if everything fits in one RPC */
38
39 #ifdef __KERNEL__
40
41 #include <linux/in.h>
42 #include <linux/mm.h>
43 #include <linux/pagemap.h>
44 #include <linux/rbtree.h>
45 #include <linux/rwsem.h>
46 #include <linux/wait.h>
47
48 #include <linux/sunrpc/debug.h>
49 #include <linux/sunrpc/auth.h>
50 #include <linux/sunrpc/clnt.h>
51
52 #include <linux/nfs.h>
53 #include <linux/nfs2.h>
54 #include <linux/nfs3.h>
55 #include <linux/nfs4.h>
56 #include <linux/nfs_xdr.h>
57 #include <linux/nfs_fs_sb.h>
58
59 #include <linux/mempool.h>
60
61 /*
62 * These are the default flags for swap requests
63 */
64 #define NFS_RPC_SWAPFLAGS (RPC_TASK_SWAPPER|RPC_TASK_ROOTCREDS)
65
66 /*
67 * NFSv3/v4 Access mode cache entry
68 */
69 struct nfs_access_entry {
70 struct rb_node rb_node;
71 struct list_head lru;
72 unsigned long jiffies;
73 struct rpc_cred * cred;
74 int mask;
75 };
76
77 struct nfs_lock_context {
78 atomic_t count;
79 struct list_head list;
80 struct nfs_open_context *open_context;
81 fl_owner_t lockowner;
82 pid_t pid;
83 };
84
85 struct nfs4_state;
86 struct nfs_open_context {
87 struct nfs_lock_context lock_context;
88 struct dentry *dentry;
89 struct rpc_cred *cred;
90 struct nfs4_state *state;
91 fmode_t mode;
92
93 unsigned long flags;
94 #define NFS_CONTEXT_ERROR_WRITE (0)
95 int error;
96
97 struct list_head list;
98 };
99
100 struct nfs_open_dir_context {
101 struct rpc_cred *cred;
102 unsigned long attr_gencount;
103 __u64 dir_cookie;
104 __u64 dup_cookie;
105 signed char duped;
106 };
107
108 /*
109 * NFSv4 delegation
110 */
111 struct nfs_delegation;
112
113 struct posix_acl;
114
115 /*
116 * nfs fs inode data in memory
117 */
118 struct nfs_inode {
119 /*
120 * The 64bit 'inode number'
121 */
122 __u64 fileid;
123
124 /*
125 * NFS file handle
126 */
127 struct nfs_fh fh;
128
129 /*
130 * Various flags
131 */
132 unsigned long flags; /* atomic bit ops */
133 unsigned long cache_validity; /* bit mask */
134
135 /*
136 * read_cache_jiffies is when we started read-caching this inode.
137 * attrtimeo is for how long the cached information is assumed
138 * to be valid. A successful attribute revalidation doubles
139 * attrtimeo (up to acregmax/acdirmax), a failure resets it to
140 * acregmin/acdirmin.
141 *
142 * We need to revalidate the cached attrs for this inode if
143 *
144 * jiffies - read_cache_jiffies >= attrtimeo
145 *
146 * Please note the comparison is greater than or equal
147 * so that zero timeout values can be specified.
148 */
149 unsigned long read_cache_jiffies;
150 unsigned long attrtimeo;
151 unsigned long attrtimeo_timestamp;
152
153 unsigned long attr_gencount;
154 /* "Generation counter" for the attribute cache. This is
155 * bumped whenever we update the metadata on the
156 * server.
157 */
158 unsigned long cache_change_attribute;
159
160 struct rb_root access_cache;
161 struct list_head access_cache_entry_lru;
162 struct list_head access_cache_inode_lru;
163 #ifdef CONFIG_NFS_V3_ACL
164 struct posix_acl *acl_access;
165 struct posix_acl *acl_default;
166 #endif
167
168 /*
169 * This is the cookie verifier used for NFSv3 readdir
170 * operations
171 */
172 __be32 cookieverf[2];
173
174 /*
175 * This is the list of dirty unwritten pages.
176 */
177 struct radix_tree_root nfs_page_tree;
178
179 unsigned long npages;
180 unsigned long ncommit;
181
182 /* Open contexts for shared mmap writes */
183 struct list_head open_files;
184
185 /* Number of in-flight sillydelete RPC calls */
186 atomic_t silly_count;
187 /* List of deferred sillydelete requests */
188 struct hlist_head silly_list;
189 wait_queue_head_t waitqueue;
190
191 #ifdef CONFIG_NFS_V4
192 struct nfs4_cached_acl *nfs4_acl;
193 /* NFSv4 state */
194 struct list_head open_states;
195 struct nfs_delegation __rcu *delegation;
196 fmode_t delegation_state;
197 struct rw_semaphore rwsem;
198
199 /* pNFS layout information */
200 struct pnfs_layout_hdr *layout;
201 atomic_t commits_outstanding;
202 #endif /* CONFIG_NFS_V4*/
203 #ifdef CONFIG_NFS_FSCACHE
204 struct fscache_cookie *fscache;
205 #endif
206 struct inode vfs_inode;
207 };
208
209 /*
210 * Cache validity bit flags
211 */
212 #define NFS_INO_INVALID_ATTR 0x0001 /* cached attrs are invalid */
213 #define NFS_INO_INVALID_DATA 0x0002 /* cached data is invalid */
214 #define NFS_INO_INVALID_ATIME 0x0004 /* cached atime is invalid */
215 #define NFS_INO_INVALID_ACCESS 0x0008 /* cached access cred invalid */
216 #define NFS_INO_INVALID_ACL 0x0010 /* cached acls are invalid */
217 #define NFS_INO_REVAL_PAGECACHE 0x0020 /* must revalidate pagecache */
218 #define NFS_INO_REVAL_FORCED 0x0040 /* force revalidation ignoring a delegation */
219
220 /*
221 * Bit offsets in flags field
222 */
223 #define NFS_INO_ADVISE_RDPLUS (0) /* advise readdirplus */
224 #define NFS_INO_STALE (1) /* possible stale inode */
225 #define NFS_INO_ACL_LRU_SET (2) /* Inode is on the LRU list */
226 #define NFS_INO_FLUSHING (4) /* inode is flushing out data */
227 #define NFS_INO_FSCACHE (5) /* inode can be cached by FS-Cache */
228 #define NFS_INO_FSCACHE_LOCK (6) /* FS-Cache cookie management lock */
229 #define NFS_INO_COMMIT (7) /* inode is committing unstable writes */
230 #define NFS_INO_PNFS_COMMIT (8) /* use pnfs code for commit */
231 #define NFS_INO_LAYOUTCOMMIT (9) /* layoutcommit required */
232 #define NFS_INO_LAYOUTCOMMITTING (10) /* layoutcommit inflight */
233
234 static inline struct nfs_inode *NFS_I(const struct inode *inode)
235 {
236 return container_of(inode, struct nfs_inode, vfs_inode);
237 }
238
239 static inline struct nfs_server *NFS_SB(const struct super_block *s)
240 {
241 return (struct nfs_server *)(s->s_fs_info);
242 }
243
244 static inline struct nfs_fh *NFS_FH(const struct inode *inode)
245 {
246 return &NFS_I(inode)->fh;
247 }
248
249 static inline struct nfs_server *NFS_SERVER(const struct inode *inode)
250 {
251 return NFS_SB(inode->i_sb);
252 }
253
254 static inline struct rpc_clnt *NFS_CLIENT(const struct inode *inode)
255 {
256 return NFS_SERVER(inode)->client;
257 }
258
259 static inline const struct nfs_rpc_ops *NFS_PROTO(const struct inode *inode)
260 {
261 return NFS_SERVER(inode)->nfs_client->rpc_ops;
262 }
263
264 static inline __be32 *NFS_COOKIEVERF(const struct inode *inode)
265 {
266 return NFS_I(inode)->cookieverf;
267 }
268
269 static inline unsigned NFS_MINATTRTIMEO(const struct inode *inode)
270 {
271 struct nfs_server *nfss = NFS_SERVER(inode);
272 return S_ISDIR(inode->i_mode) ? nfss->acdirmin : nfss->acregmin;
273 }
274
275 static inline unsigned NFS_MAXATTRTIMEO(const struct inode *inode)
276 {
277 struct nfs_server *nfss = NFS_SERVER(inode);
278 return S_ISDIR(inode->i_mode) ? nfss->acdirmax : nfss->acregmax;
279 }
280
281 static inline int NFS_STALE(const struct inode *inode)
282 {
283 return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
284 }
285
286 static inline int NFS_FSCACHE(const struct inode *inode)
287 {
288 return test_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
289 }
290
291 static inline __u64 NFS_FILEID(const struct inode *inode)
292 {
293 return NFS_I(inode)->fileid;
294 }
295
296 static inline void set_nfs_fileid(struct inode *inode, __u64 fileid)
297 {
298 NFS_I(inode)->fileid = fileid;
299 }
300
301 static inline void nfs_mark_for_revalidate(struct inode *inode)
302 {
303 struct nfs_inode *nfsi = NFS_I(inode);
304
305 spin_lock(&inode->i_lock);
306 nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS;
307 if (S_ISDIR(inode->i_mode))
308 nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA;
309 spin_unlock(&inode->i_lock);
310 }
311
312 static inline int nfs_server_capable(struct inode *inode, int cap)
313 {
314 return NFS_SERVER(inode)->caps & cap;
315 }
316
317 static inline int NFS_USE_READDIRPLUS(struct inode *inode)
318 {
319 return test_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
320 }
321
322 static inline void nfs_set_verifier(struct dentry * dentry, unsigned long verf)
323 {
324 dentry->d_time = verf;
325 }
326
327 /**
328 * nfs_save_change_attribute - Returns the inode attribute change cookie
329 * @dir - pointer to parent directory inode
330 * The "change attribute" is updated every time we finish an operation
331 * that will result in a metadata change on the server.
332 */
333 static inline unsigned long nfs_save_change_attribute(struct inode *dir)
334 {
335 return NFS_I(dir)->cache_change_attribute;
336 }
337
338 /**
339 * nfs_verify_change_attribute - Detects NFS remote directory changes
340 * @dir - pointer to parent directory inode
341 * @chattr - previously saved change attribute
342 * Return "false" if the verifiers doesn't match the change attribute.
343 * This would usually indicate that the directory contents have changed on
344 * the server, and that any dentries need revalidating.
345 */
346 static inline int nfs_verify_change_attribute(struct inode *dir, unsigned long chattr)
347 {
348 return chattr == NFS_I(dir)->cache_change_attribute;
349 }
350
351 /*
352 * linux/fs/nfs/inode.c
353 */
354 extern int nfs_sync_mapping(struct address_space *mapping);
355 extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
356 extern void nfs_zap_caches(struct inode *);
357 extern void nfs_invalidate_atime(struct inode *);
358 extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
359 struct nfs_fattr *);
360 extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
361 extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
362 extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
363 extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
364 extern int nfs_permission(struct inode *, int);
365 extern int nfs_open(struct inode *, struct file *);
366 extern int nfs_release(struct inode *, struct file *);
367 extern int nfs_attribute_timeout(struct inode *inode);
368 extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
369 extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
370 extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
371 extern int nfs_setattr(struct dentry *, struct iattr *);
372 extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
373 extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
374 extern void put_nfs_open_context(struct nfs_open_context *ctx);
375 extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode);
376 extern struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, struct rpc_cred *cred, fmode_t f_mode);
377 extern void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx);
378 extern struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx);
379 extern void nfs_put_lock_context(struct nfs_lock_context *l_ctx);
380 extern u64 nfs_compat_user_ino64(u64 fileid);
381 extern void nfs_fattr_init(struct nfs_fattr *fattr);
382 extern unsigned long nfs_inc_attr_generation_counter(void);
383
384 extern struct nfs_fattr *nfs_alloc_fattr(void);
385
386 static inline void nfs_free_fattr(const struct nfs_fattr *fattr)
387 {
388 kfree(fattr);
389 }
390
391 extern struct nfs_fh *nfs_alloc_fhandle(void);
392
393 static inline void nfs_free_fhandle(const struct nfs_fh *fh)
394 {
395 kfree(fh);
396 }
397
398 /*
399 * linux/fs/nfs/nfsroot.c
400 */
401 extern int nfs_root_data(char **root_device, char **root_data); /*__init*/
402 /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
403 extern __be32 root_nfs_parse_addr(char *name); /*__init*/
404
405 /*
406 * linux/fs/nfs/file.c
407 */
408 extern const struct inode_operations nfs_file_inode_operations;
409 #ifdef CONFIG_NFS_V3
410 extern const struct inode_operations nfs3_file_inode_operations;
411 #endif /* CONFIG_NFS_V3 */
412 extern const struct file_operations nfs_file_operations;
413 extern const struct address_space_operations nfs_file_aops;
414 extern const struct address_space_operations nfs_dir_aops;
415
416 static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
417 {
418 return filp->private_data;
419 }
420
421 static inline struct rpc_cred *nfs_file_cred(struct file *file)
422 {
423 if (file != NULL) {
424 struct nfs_open_context *ctx =
425 nfs_file_open_context(file);
426 if (ctx)
427 return ctx->cred;
428 }
429 return NULL;
430 }
431
432 /*
433 * linux/fs/nfs/xattr.c
434 */
435 #ifdef CONFIG_NFS_V3_ACL
436 extern ssize_t nfs3_listxattr(struct dentry *, char *, size_t);
437 extern ssize_t nfs3_getxattr(struct dentry *, const char *, void *, size_t);
438 extern int nfs3_setxattr(struct dentry *, const char *,
439 const void *, size_t, int);
440 extern int nfs3_removexattr (struct dentry *, const char *name);
441 #else
442 # define nfs3_listxattr NULL
443 # define nfs3_getxattr NULL
444 # define nfs3_setxattr NULL
445 # define nfs3_removexattr NULL
446 #endif
447
448 /*
449 * linux/fs/nfs/direct.c
450 */
451 extern ssize_t nfs_direct_IO(int, struct kiocb *, const struct iovec *, loff_t,
452 unsigned long);
453 extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
454 const struct iovec *iov, unsigned long nr_segs,
455 loff_t pos);
456 extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
457 const struct iovec *iov, unsigned long nr_segs,
458 loff_t pos);
459
460 /*
461 * linux/fs/nfs/dir.c
462 */
463 extern const struct inode_operations nfs_dir_inode_operations;
464 #ifdef CONFIG_NFS_V3
465 extern const struct inode_operations nfs3_dir_inode_operations;
466 #endif /* CONFIG_NFS_V3 */
467 extern const struct file_operations nfs_dir_operations;
468 extern const struct dentry_operations nfs_dentry_operations;
469
470 extern void nfs_force_lookup_revalidate(struct inode *dir);
471 extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh, struct nfs_fattr *fattr);
472 extern int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags);
473 extern void nfs_access_zap_cache(struct inode *inode);
474
475 /*
476 * linux/fs/nfs/symlink.c
477 */
478 extern const struct inode_operations nfs_symlink_inode_operations;
479
480 /*
481 * linux/fs/nfs/sysctl.c
482 */
483 #ifdef CONFIG_SYSCTL
484 extern int nfs_register_sysctl(void);
485 extern void nfs_unregister_sysctl(void);
486 #else
487 #define nfs_register_sysctl() 0
488 #define nfs_unregister_sysctl() do { } while(0)
489 #endif
490
491 /*
492 * linux/fs/nfs/namespace.c
493 */
494 extern const struct inode_operations nfs_mountpoint_inode_operations;
495 extern const struct inode_operations nfs_referral_inode_operations;
496 extern int nfs_mountpoint_expiry_timeout;
497 extern void nfs_release_automount_timer(void);
498
499 /*
500 * linux/fs/nfs/unlink.c
501 */
502 extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
503 extern void nfs_block_sillyrename(struct dentry *dentry);
504 extern void nfs_unblock_sillyrename(struct dentry *dentry);
505 extern int nfs_sillyrename(struct inode *dir, struct dentry *dentry);
506
507 /*
508 * linux/fs/nfs/write.c
509 */
510 extern int nfs_congestion_kb;
511 extern int nfs_writepage(struct page *page, struct writeback_control *wbc);
512 extern int nfs_writepages(struct address_space *, struct writeback_control *);
513 extern int nfs_flush_incompatible(struct file *file, struct page *page);
514 extern int nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
515 extern void nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
516
517 /*
518 * Try to write back everything synchronously (but check the
519 * return value!)
520 */
521 extern int nfs_wb_all(struct inode *inode);
522 extern int nfs_wb_page(struct inode *inode, struct page* page);
523 extern int nfs_wb_page_cancel(struct inode *inode, struct page* page);
524 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
525 extern int nfs_commit_inode(struct inode *, int);
526 extern struct nfs_write_data *nfs_commitdata_alloc(void);
527 extern void nfs_commit_free(struct nfs_write_data *wdata);
528 #else
529 static inline int
530 nfs_commit_inode(struct inode *inode, int how)
531 {
532 return 0;
533 }
534 #endif
535
536 static inline int
537 nfs_have_writebacks(struct inode *inode)
538 {
539 return NFS_I(inode)->npages != 0;
540 }
541
542 /*
543 * Allocate nfs_write_data structures
544 */
545 extern struct nfs_write_data *nfs_writedata_alloc(unsigned int npages);
546 extern void nfs_writedata_free(struct nfs_write_data *);
547
548 /*
549 * linux/fs/nfs/read.c
550 */
551 extern int nfs_readpage(struct file *, struct page *);
552 extern int nfs_readpages(struct file *, struct address_space *,
553 struct list_head *, unsigned);
554 extern int nfs_readpage_result(struct rpc_task *, struct nfs_read_data *);
555 extern int nfs_readpage_async(struct nfs_open_context *, struct inode *,
556 struct page *);
557
558 /*
559 * Allocate nfs_read_data structures
560 */
561 extern struct nfs_read_data *nfs_readdata_alloc(unsigned int npages);
562 extern void nfs_readdata_free(struct nfs_read_data *);
563
564 /*
565 * linux/fs/nfs3proc.c
566 */
567 #ifdef CONFIG_NFS_V3_ACL
568 extern struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type);
569 extern int nfs3_proc_setacl(struct inode *inode, int type,
570 struct posix_acl *acl);
571 extern int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode,
572 umode_t mode);
573 extern void nfs3_forget_cached_acls(struct inode *inode);
574 #else
575 static inline int nfs3_proc_set_default_acl(struct inode *dir,
576 struct inode *inode,
577 umode_t mode)
578 {
579 return 0;
580 }
581
582 static inline void nfs3_forget_cached_acls(struct inode *inode)
583 {
584 }
585 #endif /* CONFIG_NFS_V3_ACL */
586
587 /*
588 * inline functions
589 */
590
591 static inline loff_t nfs_size_to_loff_t(__u64 size)
592 {
593 if (size > (__u64) OFFSET_MAX - 1)
594 return OFFSET_MAX - 1;
595 return (loff_t) size;
596 }
597
598 static inline ino_t
599 nfs_fileid_to_ino_t(u64 fileid)
600 {
601 ino_t ino = (ino_t) fileid;
602 if (sizeof(ino_t) < sizeof(u64))
603 ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
604 return ino;
605 }
606
607 #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
608
609 #endif /* __KERNEL__ */
610
611 /*
612 * NFS debug flags
613 */
614 #define NFSDBG_VFS 0x0001
615 #define NFSDBG_DIRCACHE 0x0002
616 #define NFSDBG_LOOKUPCACHE 0x0004
617 #define NFSDBG_PAGECACHE 0x0008
618 #define NFSDBG_PROC 0x0010
619 #define NFSDBG_XDR 0x0020
620 #define NFSDBG_FILE 0x0040
621 #define NFSDBG_ROOT 0x0080
622 #define NFSDBG_CALLBACK 0x0100
623 #define NFSDBG_CLIENT 0x0200
624 #define NFSDBG_MOUNT 0x0400
625 #define NFSDBG_FSCACHE 0x0800
626 #define NFSDBG_PNFS 0x1000
627 #define NFSDBG_PNFS_LD 0x2000
628 #define NFSDBG_ALL 0xFFFF
629
630 #ifdef __KERNEL__
631
632 /*
633 * Enable debugging support for nfs client.
634 * Requires RPC_DEBUG.
635 */
636 #ifdef RPC_DEBUG
637 # define NFS_DEBUG
638 #endif
639
640 # undef ifdebug
641 # ifdef NFS_DEBUG
642 # define ifdebug(fac) if (unlikely(nfs_debug & NFSDBG_##fac))
643 # else
644 # define ifdebug(fac) if (0)
645 # endif
646 #endif /* __KERNEL */
647
648 #endif