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. /*
  11. * Enable debugging support for nfs client.
  12. * Requires RPC_DEBUG.
  13. */
  14. #ifdef RPC_DEBUG
  15. # define NFS_DEBUG
  16. #endif
  17. /* Default timeout values */
  18. #define NFS_MAX_UDP_TIMEOUT (60*HZ)
  19. #define NFS_MAX_TCP_TIMEOUT (600*HZ)
  20. /*
  21. * superblock magic number for NFS
  22. */
  23. #define NFS_SUPER_MAGIC 0x6969
  24. /*
  25. * When flushing a cluster of dirty pages, there can be different
  26. * strategies:
  27. */
  28. #define FLUSH_SYNC 1 /* file being synced, or contention */
  29. #define FLUSH_STABLE 4 /* commit to stable storage */
  30. #define FLUSH_LOWPRI 8 /* low priority background flush */
  31. #define FLUSH_HIGHPRI 16 /* high priority memory reclaim flush */
  32. #define FLUSH_NOCOMMIT 32 /* Don't send the NFSv3/v4 COMMIT */
  33. #define FLUSH_INVALIDATE 64 /* Invalidate the page cache */
  34. #ifdef __KERNEL__
  35. #include <linux/in.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/rwsem.h>
  51. #include <linux/mempool.h>
  52. /*
  53. * These are the default flags for swap requests
  54. */
  55. #define NFS_RPC_SWAPFLAGS (RPC_TASK_SWAPPER|RPC_TASK_ROOTCREDS)
  56. /*
  57. * NFSv3/v4 Access mode cache entry
  58. */
  59. struct nfs_access_entry {
  60. struct rb_node rb_node;
  61. struct list_head lru;
  62. unsigned long jiffies;
  63. struct rpc_cred * cred;
  64. int mask;
  65. };
  66. struct nfs4_state;
  67. struct nfs_open_context {
  68. atomic_t count;
  69. struct vfsmount *vfsmnt;
  70. struct dentry *dentry;
  71. struct rpc_cred *cred;
  72. struct nfs4_state *state;
  73. fl_owner_t lockowner;
  74. int mode;
  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. unsigned long read_cache_jiffies;
  113. unsigned long attrtimeo;
  114. unsigned long attrtimeo_timestamp;
  115. __u64 change_attr; /* v4 only */
  116. unsigned long last_updated;
  117. /* "Generation counter" for the attribute cache. This is
  118. * bumped whenever we update the metadata on the
  119. * server.
  120. */
  121. unsigned long cache_change_attribute;
  122. /*
  123. * Counter indicating the number of outstanding requests that
  124. * will cause a file data update.
  125. */
  126. atomic_t data_updates;
  127. struct rb_root access_cache;
  128. struct list_head access_cache_entry_lru;
  129. struct list_head access_cache_inode_lru;
  130. #ifdef CONFIG_NFS_V3_ACL
  131. struct posix_acl *acl_access;
  132. struct posix_acl *acl_default;
  133. #endif
  134. /*
  135. * This is the cookie verifier used for NFSv3 readdir
  136. * operations
  137. */
  138. __u32 cookieverf[2];
  139. /*
  140. * This is the list of dirty unwritten pages.
  141. */
  142. spinlock_t req_lock;
  143. struct list_head dirty;
  144. struct list_head commit;
  145. struct radix_tree_root nfs_page_tree;
  146. unsigned int ndirty,
  147. ncommit,
  148. npages;
  149. /* Open contexts for shared mmap writes */
  150. struct list_head open_files;
  151. #ifdef CONFIG_NFS_V4
  152. struct nfs4_cached_acl *nfs4_acl;
  153. /* NFSv4 state */
  154. struct list_head open_states;
  155. struct nfs_delegation *delegation;
  156. int delegation_state;
  157. struct rw_semaphore rwsem;
  158. #endif /* CONFIG_NFS_V4*/
  159. struct inode vfs_inode;
  160. };
  161. /*
  162. * Cache validity bit flags
  163. */
  164. #define NFS_INO_INVALID_ATTR 0x0001 /* cached attrs are invalid */
  165. #define NFS_INO_INVALID_DATA 0x0002 /* cached data is invalid */
  166. #define NFS_INO_INVALID_ATIME 0x0004 /* cached atime is invalid */
  167. #define NFS_INO_INVALID_ACCESS 0x0008 /* cached access cred invalid */
  168. #define NFS_INO_INVALID_ACL 0x0010 /* cached acls are invalid */
  169. #define NFS_INO_REVAL_PAGECACHE 0x0020 /* must revalidate pagecache */
  170. /*
  171. * Bit offsets in flags field
  172. */
  173. #define NFS_INO_REVALIDATING (0) /* revalidating attrs */
  174. #define NFS_INO_ADVISE_RDPLUS (1) /* advise readdirplus */
  175. #define NFS_INO_STALE (2) /* possible stale inode */
  176. #define NFS_INO_ACL_LRU_SET (3) /* Inode is on the LRU list */
  177. static inline struct nfs_inode *NFS_I(struct inode *inode)
  178. {
  179. return container_of(inode, struct nfs_inode, vfs_inode);
  180. }
  181. #define NFS_SB(s) ((struct nfs_server *)(s->s_fs_info))
  182. #define NFS_FH(inode) (&NFS_I(inode)->fh)
  183. #define NFS_SERVER(inode) (NFS_SB(inode->i_sb))
  184. #define NFS_CLIENT(inode) (NFS_SERVER(inode)->client)
  185. #define NFS_PROTO(inode) (NFS_SERVER(inode)->rpc_ops)
  186. #define NFS_ADDR(inode) (RPC_PEERADDR(NFS_CLIENT(inode)))
  187. #define NFS_COOKIEVERF(inode) (NFS_I(inode)->cookieverf)
  188. #define NFS_READTIME(inode) (NFS_I(inode)->read_cache_jiffies)
  189. #define NFS_CHANGE_ATTR(inode) (NFS_I(inode)->change_attr)
  190. #define NFS_ATTRTIMEO(inode) (NFS_I(inode)->attrtimeo)
  191. #define NFS_MINATTRTIMEO(inode) \
  192. (S_ISDIR(inode->i_mode)? NFS_SERVER(inode)->acdirmin \
  193. : NFS_SERVER(inode)->acregmin)
  194. #define NFS_MAXATTRTIMEO(inode) \
  195. (S_ISDIR(inode->i_mode)? NFS_SERVER(inode)->acdirmax \
  196. : NFS_SERVER(inode)->acregmax)
  197. #define NFS_ATTRTIMEO_UPDATE(inode) (NFS_I(inode)->attrtimeo_timestamp)
  198. #define NFS_FLAGS(inode) (NFS_I(inode)->flags)
  199. #define NFS_STALE(inode) (test_bit(NFS_INO_STALE, &NFS_FLAGS(inode)))
  200. #define NFS_FILEID(inode) (NFS_I(inode)->fileid)
  201. static inline int nfs_caches_unstable(struct inode *inode)
  202. {
  203. return atomic_read(&NFS_I(inode)->data_updates) != 0;
  204. }
  205. static inline void nfs_mark_for_revalidate(struct inode *inode)
  206. {
  207. struct nfs_inode *nfsi = NFS_I(inode);
  208. spin_lock(&inode->i_lock);
  209. nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS;
  210. if (S_ISDIR(inode->i_mode))
  211. nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA;
  212. spin_unlock(&inode->i_lock);
  213. }
  214. static inline void NFS_CACHEINV(struct inode *inode)
  215. {
  216. if (!nfs_caches_unstable(inode))
  217. nfs_mark_for_revalidate(inode);
  218. }
  219. static inline int nfs_server_capable(struct inode *inode, int cap)
  220. {
  221. return NFS_SERVER(inode)->caps & cap;
  222. }
  223. static inline int NFS_USE_READDIRPLUS(struct inode *inode)
  224. {
  225. return test_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
  226. }
  227. /**
  228. * nfs_save_change_attribute - Returns the inode attribute change cookie
  229. * @inode - pointer to inode
  230. * The "change attribute" is updated every time we finish an operation
  231. * that will result in a metadata change on the server.
  232. */
  233. static inline long nfs_save_change_attribute(struct inode *inode)
  234. {
  235. return NFS_I(inode)->cache_change_attribute;
  236. }
  237. /**
  238. * nfs_verify_change_attribute - Detects NFS inode cache updates
  239. * @inode - pointer to inode
  240. * @chattr - previously saved change attribute
  241. * Return "false" if metadata has been updated (or is in the process of
  242. * being updated) since the change attribute was saved.
  243. */
  244. static inline int nfs_verify_change_attribute(struct inode *inode, unsigned long chattr)
  245. {
  246. return !nfs_caches_unstable(inode)
  247. && time_after_eq(chattr, NFS_I(inode)->cache_change_attribute);
  248. }
  249. /*
  250. * linux/fs/nfs/inode.c
  251. */
  252. extern int nfs_sync_mapping(struct address_space *mapping);
  253. extern void nfs_zap_caches(struct inode *);
  254. extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
  255. struct nfs_fattr *);
  256. extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
  257. extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
  258. extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
  259. extern int nfs_permission(struct inode *, int, struct nameidata *);
  260. extern int nfs_access_get_cached(struct inode *, struct rpc_cred *, struct nfs_access_entry *);
  261. extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *);
  262. extern void nfs_access_zap_cache(struct inode *inode);
  263. extern int nfs_open(struct inode *, struct file *);
  264. extern int nfs_release(struct inode *, struct file *);
  265. extern int nfs_attribute_timeout(struct inode *inode);
  266. extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
  267. extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
  268. extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
  269. extern int nfs_setattr(struct dentry *, struct iattr *);
  270. extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
  271. extern void nfs_begin_attr_update(struct inode *);
  272. extern void nfs_end_attr_update(struct inode *);
  273. extern void nfs_begin_data_update(struct inode *);
  274. extern void nfs_end_data_update(struct inode *);
  275. extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
  276. extern void put_nfs_open_context(struct nfs_open_context *ctx);
  277. extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, int mode);
  278. extern struct vfsmount *nfs_do_submount(const struct vfsmount *mnt_parent,
  279. const struct dentry *dentry,
  280. struct nfs_fh *fh,
  281. struct nfs_fattr *fattr);
  282. /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
  283. extern u32 root_nfs_parse_addr(char *name); /*__init*/
  284. static inline void nfs_fattr_init(struct nfs_fattr *fattr)
  285. {
  286. fattr->valid = 0;
  287. fattr->time_start = jiffies;
  288. }
  289. /*
  290. * linux/fs/nfs/file.c
  291. */
  292. extern struct inode_operations nfs_file_inode_operations;
  293. #ifdef CONFIG_NFS_V3
  294. extern struct inode_operations nfs3_file_inode_operations;
  295. #endif /* CONFIG_NFS_V3 */
  296. extern const struct file_operations nfs_file_operations;
  297. extern const struct address_space_operations nfs_file_aops;
  298. static inline struct rpc_cred *nfs_file_cred(struct file *file)
  299. {
  300. if (file != NULL) {
  301. struct nfs_open_context *ctx;
  302. ctx = (struct nfs_open_context*)file->private_data;
  303. return ctx->cred;
  304. }
  305. return NULL;
  306. }
  307. /*
  308. * linux/fs/nfs/xattr.c
  309. */
  310. #ifdef CONFIG_NFS_V3_ACL
  311. extern ssize_t nfs3_listxattr(struct dentry *, char *, size_t);
  312. extern ssize_t nfs3_getxattr(struct dentry *, const char *, void *, size_t);
  313. extern int nfs3_setxattr(struct dentry *, const char *,
  314. const void *, size_t, int);
  315. extern int nfs3_removexattr (struct dentry *, const char *name);
  316. #else
  317. # define nfs3_listxattr NULL
  318. # define nfs3_getxattr NULL
  319. # define nfs3_setxattr NULL
  320. # define nfs3_removexattr NULL
  321. #endif
  322. /*
  323. * linux/fs/nfs/direct.c
  324. */
  325. extern ssize_t nfs_direct_IO(int, struct kiocb *, const struct iovec *, loff_t,
  326. unsigned long);
  327. extern ssize_t nfs_file_direct_read(struct kiocb *iocb, char __user *buf,
  328. size_t count, loff_t pos);
  329. extern ssize_t nfs_file_direct_write(struct kiocb *iocb, const char __user *buf,
  330. size_t count, loff_t pos);
  331. /*
  332. * linux/fs/nfs/dir.c
  333. */
  334. extern struct inode_operations nfs_dir_inode_operations;
  335. #ifdef CONFIG_NFS_V3
  336. extern struct inode_operations nfs3_dir_inode_operations;
  337. #endif /* CONFIG_NFS_V3 */
  338. extern const struct file_operations nfs_dir_operations;
  339. extern struct dentry_operations nfs_dentry_operations;
  340. extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh, struct nfs_fattr *fattr);
  341. /*
  342. * linux/fs/nfs/symlink.c
  343. */
  344. extern struct inode_operations nfs_symlink_inode_operations;
  345. /*
  346. * linux/fs/nfs/sysctl.c
  347. */
  348. #ifdef CONFIG_SYSCTL
  349. extern int nfs_register_sysctl(void);
  350. extern void nfs_unregister_sysctl(void);
  351. #else
  352. #define nfs_register_sysctl() 0
  353. #define nfs_unregister_sysctl() do { } while(0)
  354. #endif
  355. /*
  356. * linux/fs/nfs/namespace.c
  357. */
  358. extern struct list_head nfs_automount_list;
  359. extern struct inode_operations nfs_mountpoint_inode_operations;
  360. extern struct inode_operations nfs_referral_inode_operations;
  361. extern int nfs_mountpoint_expiry_timeout;
  362. extern void nfs_release_automount_timer(void);
  363. /*
  364. * linux/fs/nfs/unlink.c
  365. */
  366. extern int nfs_async_unlink(struct dentry *);
  367. extern void nfs_complete_unlink(struct dentry *);
  368. /*
  369. * linux/fs/nfs/write.c
  370. */
  371. extern int nfs_writepage(struct page *page, struct writeback_control *wbc);
  372. extern int nfs_writepages(struct address_space *, struct writeback_control *);
  373. extern int nfs_flush_incompatible(struct file *file, struct page *page);
  374. extern int nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
  375. extern int nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
  376. extern void nfs_writedata_release(void *);
  377. #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
  378. struct nfs_write_data *nfs_commit_alloc(void);
  379. void nfs_commit_free(struct nfs_write_data *p);
  380. #endif
  381. /*
  382. * Try to write back everything synchronously (but check the
  383. * return value!)
  384. */
  385. extern int nfs_sync_inode_wait(struct inode *, unsigned long, unsigned int, int);
  386. #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
  387. extern int nfs_commit_inode(struct inode *, int);
  388. extern void nfs_commit_release(void *wdata);
  389. #else
  390. static inline int
  391. nfs_commit_inode(struct inode *inode, int how)
  392. {
  393. return 0;
  394. }
  395. #endif
  396. static inline int
  397. nfs_have_writebacks(struct inode *inode)
  398. {
  399. return NFS_I(inode)->npages != 0;
  400. }
  401. static inline int
  402. nfs_wb_all(struct inode *inode)
  403. {
  404. int error = nfs_sync_inode_wait(inode, 0, 0, 0);
  405. return (error < 0) ? error : 0;
  406. }
  407. /*
  408. * Write back all requests on one page - we do this before reading it.
  409. */
  410. static inline int nfs_wb_page_priority(struct inode *inode, struct page* page, int how)
  411. {
  412. int error = nfs_sync_inode_wait(inode, page->index, 1,
  413. how | FLUSH_STABLE);
  414. return (error < 0) ? error : 0;
  415. }
  416. static inline int nfs_wb_page(struct inode *inode, struct page* page)
  417. {
  418. return nfs_wb_page_priority(inode, page, 0);
  419. }
  420. /*
  421. * Allocate nfs_write_data structures
  422. */
  423. extern struct nfs_write_data *nfs_writedata_alloc(size_t len);
  424. /*
  425. * linux/fs/nfs/read.c
  426. */
  427. extern int nfs_readpage(struct file *, struct page *);
  428. extern int nfs_readpages(struct file *, struct address_space *,
  429. struct list_head *, unsigned);
  430. extern int nfs_readpage_result(struct rpc_task *, struct nfs_read_data *);
  431. extern void nfs_readdata_release(void *data);
  432. /*
  433. * Allocate nfs_read_data structures
  434. */
  435. extern struct nfs_read_data *nfs_readdata_alloc(size_t len);
  436. /*
  437. * linux/fs/nfs3proc.c
  438. */
  439. #ifdef CONFIG_NFS_V3_ACL
  440. extern struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type);
  441. extern int nfs3_proc_setacl(struct inode *inode, int type,
  442. struct posix_acl *acl);
  443. extern int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode,
  444. mode_t mode);
  445. extern void nfs3_forget_cached_acls(struct inode *inode);
  446. #else
  447. static inline int nfs3_proc_set_default_acl(struct inode *dir,
  448. struct inode *inode,
  449. mode_t mode)
  450. {
  451. return 0;
  452. }
  453. static inline void nfs3_forget_cached_acls(struct inode *inode)
  454. {
  455. }
  456. #endif /* CONFIG_NFS_V3_ACL */
  457. /*
  458. * linux/fs/mount_clnt.c
  459. * (Used only by nfsroot module)
  460. */
  461. extern int nfsroot_mount(struct sockaddr_in *, char *, struct nfs_fh *,
  462. int, int);
  463. /*
  464. * inline functions
  465. */
  466. static inline loff_t
  467. nfs_size_to_loff_t(__u64 size)
  468. {
  469. loff_t maxsz = (((loff_t) ULONG_MAX) << PAGE_CACHE_SHIFT) + PAGE_CACHE_SIZE - 1;
  470. if (size > maxsz)
  471. return maxsz;
  472. return (loff_t) size;
  473. }
  474. static inline ino_t
  475. nfs_fileid_to_ino_t(u64 fileid)
  476. {
  477. ino_t ino = (ino_t) fileid;
  478. if (sizeof(ino_t) < sizeof(u64))
  479. ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
  480. return ino;
  481. }
  482. /* NFS root */
  483. extern void * nfs_root_data(void);
  484. #define nfs_wait_event(clnt, wq, condition) \
  485. ({ \
  486. int __retval = 0; \
  487. if (clnt->cl_intr) { \
  488. sigset_t oldmask; \
  489. rpc_clnt_sigmask(clnt, &oldmask); \
  490. __retval = wait_event_interruptible(wq, condition); \
  491. rpc_clnt_sigunmask(clnt, &oldmask); \
  492. } else \
  493. wait_event(wq, condition); \
  494. __retval; \
  495. })
  496. #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
  497. #endif /* __KERNEL__ */
  498. /*
  499. * NFS debug flags
  500. */
  501. #define NFSDBG_VFS 0x0001
  502. #define NFSDBG_DIRCACHE 0x0002
  503. #define NFSDBG_LOOKUPCACHE 0x0004
  504. #define NFSDBG_PAGECACHE 0x0008
  505. #define NFSDBG_PROC 0x0010
  506. #define NFSDBG_XDR 0x0020
  507. #define NFSDBG_FILE 0x0040
  508. #define NFSDBG_ROOT 0x0080
  509. #define NFSDBG_CALLBACK 0x0100
  510. #define NFSDBG_ALL 0xFFFF
  511. #ifdef __KERNEL__
  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