nfs_fs.h 16 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. static inline struct nfs_inode *NFS_I(const struct inode *inode)
  177. {
  178. return container_of(inode, struct nfs_inode, vfs_inode);
  179. }
  180. static inline struct nfs_server *NFS_SB(const struct super_block *s)
  181. {
  182. return (struct nfs_server *)(s->s_fs_info);
  183. }
  184. static inline struct nfs_fh *NFS_FH(const struct inode *inode)
  185. {
  186. return &NFS_I(inode)->fh;
  187. }
  188. static inline struct nfs_server *NFS_SERVER(const struct inode *inode)
  189. {
  190. return NFS_SB(inode->i_sb);
  191. }
  192. static inline struct rpc_clnt *NFS_CLIENT(const struct inode *inode)
  193. {
  194. return NFS_SERVER(inode)->client;
  195. }
  196. static inline const struct nfs_rpc_ops *NFS_PROTO(const struct inode *inode)
  197. {
  198. return NFS_SERVER(inode)->nfs_client->rpc_ops;
  199. }
  200. static inline __be32 *NFS_COOKIEVERF(const struct inode *inode)
  201. {
  202. return NFS_I(inode)->cookieverf;
  203. }
  204. static inline unsigned NFS_MINATTRTIMEO(const struct inode *inode)
  205. {
  206. struct nfs_server *nfss = NFS_SERVER(inode);
  207. return S_ISDIR(inode->i_mode) ? nfss->acdirmin : nfss->acregmin;
  208. }
  209. static inline unsigned NFS_MAXATTRTIMEO(const struct inode *inode)
  210. {
  211. struct nfs_server *nfss = NFS_SERVER(inode);
  212. return S_ISDIR(inode->i_mode) ? nfss->acdirmax : nfss->acregmax;
  213. }
  214. static inline int NFS_STALE(const struct inode *inode)
  215. {
  216. return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
  217. }
  218. static inline __u64 NFS_FILEID(const struct inode *inode)
  219. {
  220. return NFS_I(inode)->fileid;
  221. }
  222. static inline void set_nfs_fileid(struct inode *inode, __u64 fileid)
  223. {
  224. NFS_I(inode)->fileid = fileid;
  225. }
  226. static inline void nfs_mark_for_revalidate(struct inode *inode)
  227. {
  228. struct nfs_inode *nfsi = NFS_I(inode);
  229. spin_lock(&inode->i_lock);
  230. nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS;
  231. if (S_ISDIR(inode->i_mode))
  232. nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA;
  233. spin_unlock(&inode->i_lock);
  234. }
  235. static inline int nfs_server_capable(struct inode *inode, int cap)
  236. {
  237. return NFS_SERVER(inode)->caps & cap;
  238. }
  239. static inline int NFS_USE_READDIRPLUS(struct inode *inode)
  240. {
  241. return test_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
  242. }
  243. static inline void nfs_set_verifier(struct dentry * dentry, unsigned long verf)
  244. {
  245. dentry->d_time = verf;
  246. }
  247. /**
  248. * nfs_save_change_attribute - Returns the inode attribute change cookie
  249. * @dir - pointer to parent directory inode
  250. * The "change attribute" is updated every time we finish an operation
  251. * that will result in a metadata change on the server.
  252. */
  253. static inline unsigned long nfs_save_change_attribute(struct inode *dir)
  254. {
  255. return NFS_I(dir)->cache_change_attribute;
  256. }
  257. /**
  258. * nfs_verify_change_attribute - Detects NFS remote directory changes
  259. * @dir - pointer to parent directory inode
  260. * @chattr - previously saved change attribute
  261. * Return "false" if the verifiers doesn't match the change attribute.
  262. * This would usually indicate that the directory contents have changed on
  263. * the server, and that any dentries need revalidating.
  264. */
  265. static inline int nfs_verify_change_attribute(struct inode *dir, unsigned long chattr)
  266. {
  267. return chattr == NFS_I(dir)->cache_change_attribute;
  268. }
  269. /*
  270. * linux/fs/nfs/inode.c
  271. */
  272. extern int nfs_sync_mapping(struct address_space *mapping);
  273. extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
  274. extern void nfs_zap_caches(struct inode *);
  275. extern void nfs_invalidate_atime(struct inode *);
  276. extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
  277. struct nfs_fattr *);
  278. extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
  279. extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
  280. extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
  281. extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
  282. extern int nfs_permission(struct inode *, int);
  283. extern int nfs_open(struct inode *, struct file *);
  284. extern int nfs_release(struct inode *, struct file *);
  285. extern int nfs_attribute_timeout(struct inode *inode);
  286. extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
  287. extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
  288. extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
  289. extern int nfs_revalidate_mapping_nolock(struct inode *inode, struct address_space *mapping);
  290. extern int nfs_setattr(struct dentry *, struct iattr *);
  291. extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
  292. extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
  293. extern void put_nfs_open_context(struct nfs_open_context *ctx);
  294. extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode);
  295. extern u64 nfs_compat_user_ino64(u64 fileid);
  296. extern void nfs_fattr_init(struct nfs_fattr *fattr);
  297. /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
  298. extern __be32 root_nfs_parse_addr(char *name); /*__init*/
  299. extern unsigned long nfs_inc_attr_generation_counter(void);
  300. /*
  301. * linux/fs/nfs/file.c
  302. */
  303. extern const struct inode_operations nfs_file_inode_operations;
  304. #ifdef CONFIG_NFS_V3
  305. extern const struct inode_operations nfs3_file_inode_operations;
  306. #endif /* CONFIG_NFS_V3 */
  307. extern const struct file_operations nfs_file_operations;
  308. extern const struct address_space_operations nfs_file_aops;
  309. static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
  310. {
  311. return filp->private_data;
  312. }
  313. static inline struct rpc_cred *nfs_file_cred(struct file *file)
  314. {
  315. if (file != NULL) {
  316. struct nfs_open_context *ctx =
  317. nfs_file_open_context(file);
  318. if (ctx)
  319. return ctx->cred;
  320. }
  321. return NULL;
  322. }
  323. /*
  324. * linux/fs/nfs/xattr.c
  325. */
  326. #ifdef CONFIG_NFS_V3_ACL
  327. extern ssize_t nfs3_listxattr(struct dentry *, char *, size_t);
  328. extern ssize_t nfs3_getxattr(struct dentry *, const char *, void *, size_t);
  329. extern int nfs3_setxattr(struct dentry *, const char *,
  330. const void *, size_t, int);
  331. extern int nfs3_removexattr (struct dentry *, const char *name);
  332. #else
  333. # define nfs3_listxattr NULL
  334. # define nfs3_getxattr NULL
  335. # define nfs3_setxattr NULL
  336. # define nfs3_removexattr NULL
  337. #endif
  338. /*
  339. * linux/fs/nfs/direct.c
  340. */
  341. extern ssize_t nfs_direct_IO(int, struct kiocb *, const struct iovec *, loff_t,
  342. unsigned long);
  343. extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
  344. const struct iovec *iov, unsigned long nr_segs,
  345. loff_t pos);
  346. extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
  347. const struct iovec *iov, unsigned long nr_segs,
  348. loff_t pos);
  349. /*
  350. * linux/fs/nfs/dir.c
  351. */
  352. extern const struct inode_operations nfs_dir_inode_operations;
  353. #ifdef CONFIG_NFS_V3
  354. extern const struct inode_operations nfs3_dir_inode_operations;
  355. #endif /* CONFIG_NFS_V3 */
  356. extern const struct file_operations nfs_dir_operations;
  357. extern struct dentry_operations nfs_dentry_operations;
  358. extern void nfs_force_lookup_revalidate(struct inode *dir);
  359. extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh, struct nfs_fattr *fattr);
  360. extern int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags);
  361. extern void nfs_access_zap_cache(struct inode *inode);
  362. /*
  363. * linux/fs/nfs/symlink.c
  364. */
  365. extern const struct inode_operations nfs_symlink_inode_operations;
  366. /*
  367. * linux/fs/nfs/sysctl.c
  368. */
  369. #ifdef CONFIG_SYSCTL
  370. extern int nfs_register_sysctl(void);
  371. extern void nfs_unregister_sysctl(void);
  372. #else
  373. #define nfs_register_sysctl() 0
  374. #define nfs_unregister_sysctl() do { } while(0)
  375. #endif
  376. /*
  377. * linux/fs/nfs/namespace.c
  378. */
  379. extern const struct inode_operations nfs_mountpoint_inode_operations;
  380. extern const struct inode_operations nfs_referral_inode_operations;
  381. extern int nfs_mountpoint_expiry_timeout;
  382. extern void nfs_release_automount_timer(void);
  383. /*
  384. * linux/fs/nfs/unlink.c
  385. */
  386. extern int nfs_async_unlink(struct inode *dir, struct dentry *dentry);
  387. extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
  388. extern void nfs_block_sillyrename(struct dentry *dentry);
  389. extern void nfs_unblock_sillyrename(struct dentry *dentry);
  390. /*
  391. * linux/fs/nfs/write.c
  392. */
  393. extern int nfs_congestion_kb;
  394. extern int nfs_writepage(struct page *page, struct writeback_control *wbc);
  395. extern int nfs_writepages(struct address_space *, struct writeback_control *);
  396. extern int nfs_flush_incompatible(struct file *file, struct page *page);
  397. extern int nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
  398. extern int nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
  399. extern void nfs_writedata_release(void *);
  400. /*
  401. * Try to write back everything synchronously (but check the
  402. * return value!)
  403. */
  404. extern long nfs_sync_mapping_wait(struct address_space *, struct writeback_control *, int);
  405. extern int nfs_wb_all(struct inode *inode);
  406. extern int nfs_wb_nocommit(struct inode *inode);
  407. extern int nfs_wb_page(struct inode *inode, struct page* page);
  408. extern int nfs_wb_page_cancel(struct inode *inode, struct page* page);
  409. #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
  410. extern int nfs_commit_inode(struct inode *, int);
  411. extern struct nfs_write_data *nfs_commitdata_alloc(void);
  412. extern void nfs_commit_free(struct nfs_write_data *wdata);
  413. extern void nfs_commitdata_release(void *wdata);
  414. #else
  415. static inline int
  416. nfs_commit_inode(struct inode *inode, int how)
  417. {
  418. return 0;
  419. }
  420. #endif
  421. static inline int
  422. nfs_have_writebacks(struct inode *inode)
  423. {
  424. return NFS_I(inode)->npages != 0;
  425. }
  426. /*
  427. * Allocate nfs_write_data structures
  428. */
  429. extern struct nfs_write_data *nfs_writedata_alloc(unsigned int npages);
  430. /*
  431. * linux/fs/nfs/read.c
  432. */
  433. extern int nfs_readpage(struct file *, struct page *);
  434. extern int nfs_readpages(struct file *, struct address_space *,
  435. struct list_head *, unsigned);
  436. extern int nfs_readpage_result(struct rpc_task *, struct nfs_read_data *);
  437. extern void nfs_readdata_release(void *data);
  438. /*
  439. * Allocate nfs_read_data structures
  440. */
  441. extern struct nfs_read_data *nfs_readdata_alloc(unsigned int npages);
  442. /*
  443. * linux/fs/nfs3proc.c
  444. */
  445. #ifdef CONFIG_NFS_V3_ACL
  446. extern struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type);
  447. extern int nfs3_proc_setacl(struct inode *inode, int type,
  448. struct posix_acl *acl);
  449. extern int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode,
  450. mode_t mode);
  451. extern void nfs3_forget_cached_acls(struct inode *inode);
  452. #else
  453. static inline int nfs3_proc_set_default_acl(struct inode *dir,
  454. struct inode *inode,
  455. mode_t mode)
  456. {
  457. return 0;
  458. }
  459. static inline void nfs3_forget_cached_acls(struct inode *inode)
  460. {
  461. }
  462. #endif /* CONFIG_NFS_V3_ACL */
  463. /*
  464. * inline functions
  465. */
  466. static inline loff_t nfs_size_to_loff_t(__u64 size)
  467. {
  468. if (size > (__u64) OFFSET_MAX - 1)
  469. return OFFSET_MAX - 1;
  470. return (loff_t) size;
  471. }
  472. static inline ino_t
  473. nfs_fileid_to_ino_t(u64 fileid)
  474. {
  475. ino_t ino = (ino_t) fileid;
  476. if (sizeof(ino_t) < sizeof(u64))
  477. ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
  478. return ino;
  479. }
  480. /* NFS root */
  481. extern void * nfs_root_data(void);
  482. #define nfs_wait_event(clnt, wq, condition) \
  483. ({ \
  484. int __retval = wait_event_killable(wq, condition); \
  485. __retval; \
  486. })
  487. #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
  488. #endif /* __KERNEL__ */
  489. /*
  490. * NFS debug flags
  491. */
  492. #define NFSDBG_VFS 0x0001
  493. #define NFSDBG_DIRCACHE 0x0002
  494. #define NFSDBG_LOOKUPCACHE 0x0004
  495. #define NFSDBG_PAGECACHE 0x0008
  496. #define NFSDBG_PROC 0x0010
  497. #define NFSDBG_XDR 0x0020
  498. #define NFSDBG_FILE 0x0040
  499. #define NFSDBG_ROOT 0x0080
  500. #define NFSDBG_CALLBACK 0x0100
  501. #define NFSDBG_CLIENT 0x0200
  502. #define NFSDBG_MOUNT 0x0400
  503. #define NFSDBG_ALL 0xFFFF
  504. #ifdef __KERNEL__
  505. /*
  506. * Enable debugging support for nfs client.
  507. * Requires RPC_DEBUG.
  508. */
  509. #ifdef RPC_DEBUG
  510. # define NFS_DEBUG
  511. #endif
  512. # undef ifdebug
  513. # ifdef NFS_DEBUG
  514. # define ifdebug(fac) if (unlikely(nfs_debug & NFSDBG_##fac))
  515. # else
  516. # define ifdebug(fac) if (0)
  517. # endif
  518. #endif /* __KERNEL */
  519. #endif