nfs_fs.h 17 KB

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