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 <uapi/linux/nfs_fs.h>
  11. /*
  12. * Enable dprintk() debugging support for nfs client.
  13. */
  14. #ifdef CONFIG_NFS_DEBUG
  15. # define NFS_DEBUG
  16. #endif
  17. #include <linux/in.h>
  18. #include <linux/mm.h>
  19. #include <linux/pagemap.h>
  20. #include <linux/rbtree.h>
  21. #include <linux/rwsem.h>
  22. #include <linux/wait.h>
  23. #include <linux/sunrpc/debug.h>
  24. #include <linux/sunrpc/auth.h>
  25. #include <linux/sunrpc/clnt.h>
  26. #include <linux/nfs.h>
  27. #include <linux/nfs2.h>
  28. #include <linux/nfs3.h>
  29. #include <linux/nfs4.h>
  30. #include <linux/nfs_xdr.h>
  31. #include <linux/nfs_fs_sb.h>
  32. #include <linux/mempool.h>
  33. /*
  34. * These are the default flags for swap requests
  35. */
  36. #define NFS_RPC_SWAPFLAGS (RPC_TASK_SWAPPER|RPC_TASK_ROOTCREDS)
  37. /*
  38. * NFSv3/v4 Access mode cache entry
  39. */
  40. struct nfs_access_entry {
  41. struct rb_node rb_node;
  42. struct list_head lru;
  43. unsigned long jiffies;
  44. struct rpc_cred * cred;
  45. int mask;
  46. };
  47. struct nfs_lockowner {
  48. fl_owner_t l_owner;
  49. pid_t l_pid;
  50. };
  51. struct nfs_lock_context {
  52. atomic_t count;
  53. struct list_head list;
  54. struct nfs_open_context *open_context;
  55. struct nfs_lockowner lockowner;
  56. };
  57. struct nfs4_state;
  58. struct nfs_open_context {
  59. struct nfs_lock_context lock_context;
  60. struct dentry *dentry;
  61. struct rpc_cred *cred;
  62. struct nfs4_state *state;
  63. fmode_t mode;
  64. unsigned long flags;
  65. #define NFS_CONTEXT_ERROR_WRITE (0)
  66. #define NFS_CONTEXT_RESEND_WRITES (1)
  67. #define NFS_CONTEXT_BAD (2)
  68. int error;
  69. struct list_head list;
  70. struct nfs4_threshold *mdsthreshold;
  71. };
  72. struct nfs_open_dir_context {
  73. struct rpc_cred *cred;
  74. unsigned long attr_gencount;
  75. __u64 dir_cookie;
  76. __u64 dup_cookie;
  77. signed char duped;
  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. unsigned long attr_gencount;
  119. /* "Generation counter" for the attribute cache. This is
  120. * bumped whenever we update the metadata on the
  121. * server.
  122. */
  123. unsigned long cache_change_attribute;
  124. struct rb_root access_cache;
  125. struct list_head access_cache_entry_lru;
  126. struct list_head access_cache_inode_lru;
  127. #ifdef CONFIG_NFS_V3_ACL
  128. struct posix_acl *acl_access;
  129. struct posix_acl *acl_default;
  130. #endif
  131. /*
  132. * This is the cookie verifier used for NFSv3 readdir
  133. * operations
  134. */
  135. __be32 cookieverf[2];
  136. unsigned long npages;
  137. struct nfs_mds_commit_info commit_info;
  138. /* Open contexts for shared mmap writes */
  139. struct list_head open_files;
  140. /* Number of in-flight sillydelete RPC calls */
  141. atomic_t silly_count;
  142. /* List of deferred sillydelete requests */
  143. struct hlist_head silly_list;
  144. wait_queue_head_t waitqueue;
  145. #if IS_ENABLED(CONFIG_NFS_V4)
  146. struct nfs4_cached_acl *nfs4_acl;
  147. /* NFSv4 state */
  148. struct list_head open_states;
  149. struct nfs_delegation __rcu *delegation;
  150. fmode_t delegation_state;
  151. struct rw_semaphore rwsem;
  152. /* pNFS layout information */
  153. struct pnfs_layout_hdr *layout;
  154. #endif /* CONFIG_NFS_V4*/
  155. /* how many bytes have been written/read and how many bytes queued up */
  156. __u64 write_io;
  157. __u64 read_io;
  158. #ifdef CONFIG_NFS_FSCACHE
  159. struct fscache_cookie *fscache;
  160. #endif
  161. struct inode vfs_inode;
  162. };
  163. /*
  164. * Cache validity bit flags
  165. */
  166. #define NFS_INO_INVALID_ATTR 0x0001 /* cached attrs are invalid */
  167. #define NFS_INO_INVALID_DATA 0x0002 /* cached data is invalid */
  168. #define NFS_INO_INVALID_ATIME 0x0004 /* cached atime is invalid */
  169. #define NFS_INO_INVALID_ACCESS 0x0008 /* cached access cred invalid */
  170. #define NFS_INO_INVALID_ACL 0x0010 /* cached acls are invalid */
  171. #define NFS_INO_REVAL_PAGECACHE 0x0020 /* must revalidate pagecache */
  172. #define NFS_INO_REVAL_FORCED 0x0040 /* force revalidation ignoring a delegation */
  173. /*
  174. * Bit offsets in flags field
  175. */
  176. #define NFS_INO_ADVISE_RDPLUS (0) /* advise readdirplus */
  177. #define NFS_INO_STALE (1) /* possible stale inode */
  178. #define NFS_INO_ACL_LRU_SET (2) /* Inode is on the LRU list */
  179. #define NFS_INO_FLUSHING (4) /* inode is flushing out data */
  180. #define NFS_INO_FSCACHE (5) /* inode can be cached by FS-Cache */
  181. #define NFS_INO_FSCACHE_LOCK (6) /* FS-Cache cookie management lock */
  182. #define NFS_INO_COMMIT (7) /* inode is committing unstable writes */
  183. #define NFS_INO_LAYOUTCOMMIT (9) /* layoutcommit required */
  184. #define NFS_INO_LAYOUTCOMMITTING (10) /* layoutcommit inflight */
  185. static inline struct nfs_inode *NFS_I(const struct inode *inode)
  186. {
  187. return container_of(inode, struct nfs_inode, vfs_inode);
  188. }
  189. static inline struct nfs_server *NFS_SB(const struct super_block *s)
  190. {
  191. return (struct nfs_server *)(s->s_fs_info);
  192. }
  193. static inline struct nfs_fh *NFS_FH(const struct inode *inode)
  194. {
  195. return &NFS_I(inode)->fh;
  196. }
  197. static inline struct nfs_server *NFS_SERVER(const struct inode *inode)
  198. {
  199. return NFS_SB(inode->i_sb);
  200. }
  201. static inline struct rpc_clnt *NFS_CLIENT(const struct inode *inode)
  202. {
  203. return NFS_SERVER(inode)->client;
  204. }
  205. static inline const struct nfs_rpc_ops *NFS_PROTO(const struct inode *inode)
  206. {
  207. return NFS_SERVER(inode)->nfs_client->rpc_ops;
  208. }
  209. static inline unsigned NFS_MINATTRTIMEO(const struct inode *inode)
  210. {
  211. struct nfs_server *nfss = NFS_SERVER(inode);
  212. return S_ISDIR(inode->i_mode) ? nfss->acdirmin : nfss->acregmin;
  213. }
  214. static inline unsigned NFS_MAXATTRTIMEO(const struct inode *inode)
  215. {
  216. struct nfs_server *nfss = NFS_SERVER(inode);
  217. return S_ISDIR(inode->i_mode) ? nfss->acdirmax : nfss->acregmax;
  218. }
  219. static inline int NFS_STALE(const struct inode *inode)
  220. {
  221. return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
  222. }
  223. static inline int NFS_FSCACHE(const struct inode *inode)
  224. {
  225. return test_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
  226. }
  227. static inline __u64 NFS_FILEID(const struct inode *inode)
  228. {
  229. return NFS_I(inode)->fileid;
  230. }
  231. static inline void set_nfs_fileid(struct inode *inode, __u64 fileid)
  232. {
  233. NFS_I(inode)->fileid = fileid;
  234. }
  235. static inline void nfs_mark_for_revalidate(struct inode *inode)
  236. {
  237. struct nfs_inode *nfsi = NFS_I(inode);
  238. spin_lock(&inode->i_lock);
  239. nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS;
  240. if (S_ISDIR(inode->i_mode))
  241. nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA;
  242. spin_unlock(&inode->i_lock);
  243. }
  244. static inline int nfs_server_capable(struct inode *inode, int cap)
  245. {
  246. return NFS_SERVER(inode)->caps & cap;
  247. }
  248. static inline void nfs_set_verifier(struct dentry * dentry, unsigned long verf)
  249. {
  250. dentry->d_time = verf;
  251. }
  252. /**
  253. * nfs_save_change_attribute - Returns the inode attribute change cookie
  254. * @dir - pointer to parent directory inode
  255. * The "change attribute" is updated every time we finish an operation
  256. * that will result in a metadata change on the server.
  257. */
  258. static inline unsigned long nfs_save_change_attribute(struct inode *dir)
  259. {
  260. return NFS_I(dir)->cache_change_attribute;
  261. }
  262. /**
  263. * nfs_verify_change_attribute - Detects NFS remote directory changes
  264. * @dir - pointer to parent directory inode
  265. * @chattr - previously saved change attribute
  266. * Return "false" if the verifiers doesn't match the change attribute.
  267. * This would usually indicate that the directory contents have changed on
  268. * the server, and that any dentries need revalidating.
  269. */
  270. static inline int nfs_verify_change_attribute(struct inode *dir, unsigned long chattr)
  271. {
  272. return chattr == NFS_I(dir)->cache_change_attribute;
  273. }
  274. /*
  275. * linux/fs/nfs/inode.c
  276. */
  277. extern int nfs_sync_mapping(struct address_space *mapping);
  278. extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
  279. extern void nfs_zap_caches(struct inode *);
  280. extern void nfs_invalidate_atime(struct inode *);
  281. extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
  282. struct nfs_fattr *);
  283. extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
  284. extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
  285. extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
  286. extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
  287. extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *);
  288. extern void nfs_access_set_mask(struct nfs_access_entry *, u32);
  289. extern int nfs_permission(struct inode *, int);
  290. extern int nfs_open(struct inode *, struct file *);
  291. extern int nfs_release(struct inode *, struct file *);
  292. extern int nfs_attribute_timeout(struct inode *inode);
  293. extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
  294. extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
  295. extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
  296. extern int nfs_setattr(struct dentry *, struct iattr *);
  297. extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
  298. extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
  299. extern void put_nfs_open_context(struct nfs_open_context *ctx);
  300. extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode);
  301. extern struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode);
  302. extern void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx);
  303. extern struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx);
  304. extern void nfs_put_lock_context(struct nfs_lock_context *l_ctx);
  305. extern u64 nfs_compat_user_ino64(u64 fileid);
  306. extern void nfs_fattr_init(struct nfs_fattr *fattr);
  307. extern unsigned long nfs_inc_attr_generation_counter(void);
  308. extern struct nfs_fattr *nfs_alloc_fattr(void);
  309. static inline void nfs_free_fattr(const struct nfs_fattr *fattr)
  310. {
  311. kfree(fattr);
  312. }
  313. extern struct nfs_fh *nfs_alloc_fhandle(void);
  314. static inline void nfs_free_fhandle(const struct nfs_fh *fh)
  315. {
  316. kfree(fh);
  317. }
  318. #ifdef NFS_DEBUG
  319. extern u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh);
  320. static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
  321. {
  322. return _nfs_display_fhandle_hash(fh);
  323. }
  324. extern void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption);
  325. #define nfs_display_fhandle(fh, caption) \
  326. do { \
  327. if (unlikely(nfs_debug & NFSDBG_FACILITY)) \
  328. _nfs_display_fhandle(fh, caption); \
  329. } while (0)
  330. #else
  331. static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
  332. {
  333. return 0;
  334. }
  335. static inline void nfs_display_fhandle(const struct nfs_fh *fh,
  336. const char *caption)
  337. {
  338. }
  339. #endif
  340. /*
  341. * linux/fs/nfs/nfsroot.c
  342. */
  343. extern int nfs_root_data(char **root_device, char **root_data); /*__init*/
  344. /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
  345. extern __be32 root_nfs_parse_addr(char *name); /*__init*/
  346. /*
  347. * linux/fs/nfs/file.c
  348. */
  349. extern const struct file_operations nfs_file_operations;
  350. #if IS_ENABLED(CONFIG_NFS_V4)
  351. extern const struct file_operations nfs4_file_operations;
  352. #endif /* CONFIG_NFS_V4 */
  353. extern const struct address_space_operations nfs_file_aops;
  354. extern const struct address_space_operations nfs_dir_aops;
  355. static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
  356. {
  357. return filp->private_data;
  358. }
  359. static inline struct rpc_cred *nfs_file_cred(struct file *file)
  360. {
  361. if (file != NULL) {
  362. struct nfs_open_context *ctx =
  363. nfs_file_open_context(file);
  364. if (ctx)
  365. return ctx->cred;
  366. }
  367. return NULL;
  368. }
  369. /*
  370. * linux/fs/nfs/xattr.c
  371. */
  372. #ifdef CONFIG_NFS_V3_ACL
  373. extern ssize_t nfs3_listxattr(struct dentry *, char *, size_t);
  374. extern ssize_t nfs3_getxattr(struct dentry *, const char *, void *, size_t);
  375. extern int nfs3_setxattr(struct dentry *, const char *,
  376. const void *, size_t, int);
  377. extern int nfs3_removexattr (struct dentry *, const char *name);
  378. #else
  379. # define nfs3_listxattr NULL
  380. # define nfs3_getxattr NULL
  381. # define nfs3_setxattr NULL
  382. # define nfs3_removexattr NULL
  383. #endif
  384. /*
  385. * linux/fs/nfs/direct.c
  386. */
  387. extern ssize_t nfs_direct_IO(int, struct kiocb *, const struct iovec *, loff_t,
  388. unsigned long);
  389. extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
  390. const struct iovec *iov, unsigned long nr_segs,
  391. loff_t pos, bool uio);
  392. extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
  393. const struct iovec *iov, unsigned long nr_segs,
  394. loff_t pos, bool uio);
  395. /*
  396. * linux/fs/nfs/dir.c
  397. */
  398. extern const struct file_operations nfs_dir_operations;
  399. extern const struct dentry_operations nfs_dentry_operations;
  400. extern void nfs_force_lookup_revalidate(struct inode *dir);
  401. extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh, struct nfs_fattr *fattr);
  402. extern int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags);
  403. extern void nfs_access_zap_cache(struct inode *inode);
  404. /*
  405. * linux/fs/nfs/symlink.c
  406. */
  407. extern const struct inode_operations nfs_symlink_inode_operations;
  408. /*
  409. * linux/fs/nfs/sysctl.c
  410. */
  411. #ifdef CONFIG_SYSCTL
  412. extern int nfs_register_sysctl(void);
  413. extern void nfs_unregister_sysctl(void);
  414. #else
  415. #define nfs_register_sysctl() 0
  416. #define nfs_unregister_sysctl() do { } while(0)
  417. #endif
  418. /*
  419. * linux/fs/nfs/namespace.c
  420. */
  421. extern const struct inode_operations nfs_mountpoint_inode_operations;
  422. extern const struct inode_operations nfs_referral_inode_operations;
  423. extern int nfs_mountpoint_expiry_timeout;
  424. extern void nfs_release_automount_timer(void);
  425. /*
  426. * linux/fs/nfs/unlink.c
  427. */
  428. extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
  429. extern void nfs_block_sillyrename(struct dentry *dentry);
  430. extern void nfs_unblock_sillyrename(struct dentry *dentry);
  431. extern int nfs_sillyrename(struct inode *dir, struct dentry *dentry);
  432. /*
  433. * linux/fs/nfs/write.c
  434. */
  435. extern int nfs_congestion_kb;
  436. extern int nfs_writepage(struct page *page, struct writeback_control *wbc);
  437. extern int nfs_writepages(struct address_space *, struct writeback_control *);
  438. extern int nfs_flush_incompatible(struct file *file, struct page *page);
  439. extern int nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
  440. extern void nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
  441. /*
  442. * Try to write back everything synchronously (but check the
  443. * return value!)
  444. */
  445. extern int nfs_wb_all(struct inode *inode);
  446. extern int nfs_wb_page(struct inode *inode, struct page* page);
  447. extern int nfs_wb_page_cancel(struct inode *inode, struct page* page);
  448. #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
  449. extern int nfs_commit_inode(struct inode *, int);
  450. extern struct nfs_commit_data *nfs_commitdata_alloc(void);
  451. extern void nfs_commit_free(struct nfs_commit_data *data);
  452. #else
  453. static inline int
  454. nfs_commit_inode(struct inode *inode, int how)
  455. {
  456. return 0;
  457. }
  458. #endif
  459. static inline int
  460. nfs_have_writebacks(struct inode *inode)
  461. {
  462. return NFS_I(inode)->npages != 0;
  463. }
  464. /*
  465. * linux/fs/nfs/read.c
  466. */
  467. extern int nfs_readpage(struct file *, struct page *);
  468. extern int nfs_readpages(struct file *, struct address_space *,
  469. struct list_head *, unsigned);
  470. extern int nfs_readpage_result(struct rpc_task *, struct nfs_read_data *);
  471. extern int nfs_readpage_async(struct nfs_open_context *, struct inode *,
  472. struct page *);
  473. /*
  474. * linux/fs/nfs3proc.c
  475. */
  476. #ifdef CONFIG_NFS_V3_ACL
  477. extern struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type);
  478. extern int nfs3_proc_setacl(struct inode *inode, int type,
  479. struct posix_acl *acl);
  480. extern int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode,
  481. umode_t mode);
  482. extern void nfs3_forget_cached_acls(struct inode *inode);
  483. #else
  484. static inline int nfs3_proc_set_default_acl(struct inode *dir,
  485. struct inode *inode,
  486. umode_t mode)
  487. {
  488. return 0;
  489. }
  490. static inline void nfs3_forget_cached_acls(struct inode *inode)
  491. {
  492. }
  493. #endif /* CONFIG_NFS_V3_ACL */
  494. /*
  495. * inline functions
  496. */
  497. static inline loff_t nfs_size_to_loff_t(__u64 size)
  498. {
  499. if (size > (__u64) OFFSET_MAX - 1)
  500. return OFFSET_MAX - 1;
  501. return (loff_t) size;
  502. }
  503. static inline ino_t
  504. nfs_fileid_to_ino_t(u64 fileid)
  505. {
  506. ino_t ino = (ino_t) fileid;
  507. if (sizeof(ino_t) < sizeof(u64))
  508. ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
  509. return ino;
  510. }
  511. #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
  512. # undef ifdebug
  513. # ifdef NFS_DEBUG
  514. # define ifdebug(fac) if (unlikely(nfs_debug & NFSDBG_##fac))
  515. # define NFS_IFDEBUG(x) x
  516. # else
  517. # define ifdebug(fac) if (0)
  518. # define NFS_IFDEBUG(x)
  519. # endif
  520. #endif