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. #define NFS_IO_INPROGRESS 0
  52. struct nfs_io_counter {
  53. unsigned long flags;
  54. atomic_t io_count;
  55. };
  56. struct nfs_lock_context {
  57. atomic_t count;
  58. struct list_head list;
  59. struct nfs_open_context *open_context;
  60. struct nfs_lockowner lockowner;
  61. struct nfs_io_counter io_count;
  62. };
  63. struct nfs4_state;
  64. struct nfs_open_context {
  65. struct nfs_lock_context lock_context;
  66. struct dentry *dentry;
  67. struct rpc_cred *cred;
  68. struct nfs4_state *state;
  69. fmode_t mode;
  70. unsigned long flags;
  71. #define NFS_CONTEXT_ERROR_WRITE (0)
  72. #define NFS_CONTEXT_RESEND_WRITES (1)
  73. #define NFS_CONTEXT_BAD (2)
  74. int error;
  75. struct list_head list;
  76. struct nfs4_threshold *mdsthreshold;
  77. };
  78. struct nfs_open_dir_context {
  79. struct rpc_cred *cred;
  80. unsigned long attr_gencount;
  81. __u64 dir_cookie;
  82. __u64 dup_cookie;
  83. signed char duped;
  84. };
  85. /*
  86. * NFSv4 delegation
  87. */
  88. struct nfs_delegation;
  89. struct posix_acl;
  90. /*
  91. * nfs fs inode data in memory
  92. */
  93. struct nfs_inode {
  94. /*
  95. * The 64bit 'inode number'
  96. */
  97. __u64 fileid;
  98. /*
  99. * NFS file handle
  100. */
  101. struct nfs_fh fh;
  102. /*
  103. * Various flags
  104. */
  105. unsigned long flags; /* atomic bit ops */
  106. unsigned long cache_validity; /* bit mask */
  107. /*
  108. * read_cache_jiffies is when we started read-caching this inode.
  109. * attrtimeo is for how long the cached information is assumed
  110. * to be valid. A successful attribute revalidation doubles
  111. * attrtimeo (up to acregmax/acdirmax), a failure resets it to
  112. * acregmin/acdirmin.
  113. *
  114. * We need to revalidate the cached attrs for this inode if
  115. *
  116. * jiffies - read_cache_jiffies >= attrtimeo
  117. *
  118. * Please note the comparison is greater than or equal
  119. * so that zero timeout values can be specified.
  120. */
  121. unsigned long read_cache_jiffies;
  122. unsigned long attrtimeo;
  123. unsigned long attrtimeo_timestamp;
  124. unsigned long attr_gencount;
  125. /* "Generation counter" for the attribute cache. This is
  126. * bumped whenever we update the metadata on the
  127. * server.
  128. */
  129. unsigned long cache_change_attribute;
  130. struct rb_root access_cache;
  131. struct list_head access_cache_entry_lru;
  132. struct list_head access_cache_inode_lru;
  133. #ifdef CONFIG_NFS_V3_ACL
  134. struct posix_acl *acl_access;
  135. struct posix_acl *acl_default;
  136. #endif
  137. /*
  138. * This is the cookie verifier used for NFSv3 readdir
  139. * operations
  140. */
  141. __be32 cookieverf[2];
  142. unsigned long npages;
  143. struct nfs_mds_commit_info commit_info;
  144. /* Open contexts for shared mmap writes */
  145. struct list_head open_files;
  146. /* Number of in-flight sillydelete RPC calls */
  147. atomic_t silly_count;
  148. /* List of deferred sillydelete requests */
  149. struct hlist_head silly_list;
  150. wait_queue_head_t waitqueue;
  151. #if IS_ENABLED(CONFIG_NFS_V4)
  152. struct nfs4_cached_acl *nfs4_acl;
  153. /* NFSv4 state */
  154. struct list_head open_states;
  155. struct nfs_delegation __rcu *delegation;
  156. fmode_t delegation_state;
  157. struct rw_semaphore rwsem;
  158. /* pNFS layout information */
  159. struct pnfs_layout_hdr *layout;
  160. #endif /* CONFIG_NFS_V4*/
  161. /* how many bytes have been written/read and how many bytes queued up */
  162. __u64 write_io;
  163. __u64 read_io;
  164. #ifdef CONFIG_NFS_FSCACHE
  165. struct fscache_cookie *fscache;
  166. #endif
  167. struct inode vfs_inode;
  168. };
  169. /*
  170. * Cache validity bit flags
  171. */
  172. #define NFS_INO_INVALID_ATTR 0x0001 /* cached attrs are invalid */
  173. #define NFS_INO_INVALID_DATA 0x0002 /* cached data is invalid */
  174. #define NFS_INO_INVALID_ATIME 0x0004 /* cached atime is invalid */
  175. #define NFS_INO_INVALID_ACCESS 0x0008 /* cached access cred invalid */
  176. #define NFS_INO_INVALID_ACL 0x0010 /* cached acls are invalid */
  177. #define NFS_INO_REVAL_PAGECACHE 0x0020 /* must revalidate pagecache */
  178. #define NFS_INO_REVAL_FORCED 0x0040 /* force revalidation ignoring a delegation */
  179. /*
  180. * Bit offsets in flags field
  181. */
  182. #define NFS_INO_ADVISE_RDPLUS (0) /* advise readdirplus */
  183. #define NFS_INO_STALE (1) /* possible stale inode */
  184. #define NFS_INO_ACL_LRU_SET (2) /* Inode is on the LRU list */
  185. #define NFS_INO_FLUSHING (4) /* inode is flushing out data */
  186. #define NFS_INO_FSCACHE (5) /* inode can be cached by FS-Cache */
  187. #define NFS_INO_FSCACHE_LOCK (6) /* FS-Cache cookie management lock */
  188. #define NFS_INO_COMMIT (7) /* inode is committing unstable writes */
  189. #define NFS_INO_LAYOUTCOMMIT (9) /* layoutcommit required */
  190. #define NFS_INO_LAYOUTCOMMITTING (10) /* layoutcommit inflight */
  191. static inline struct nfs_inode *NFS_I(const struct inode *inode)
  192. {
  193. return container_of(inode, struct nfs_inode, vfs_inode);
  194. }
  195. static inline struct nfs_server *NFS_SB(const struct super_block *s)
  196. {
  197. return (struct nfs_server *)(s->s_fs_info);
  198. }
  199. static inline struct nfs_fh *NFS_FH(const struct inode *inode)
  200. {
  201. return &NFS_I(inode)->fh;
  202. }
  203. static inline struct nfs_server *NFS_SERVER(const struct inode *inode)
  204. {
  205. return NFS_SB(inode->i_sb);
  206. }
  207. static inline struct rpc_clnt *NFS_CLIENT(const struct inode *inode)
  208. {
  209. return NFS_SERVER(inode)->client;
  210. }
  211. static inline const struct nfs_rpc_ops *NFS_PROTO(const struct inode *inode)
  212. {
  213. return NFS_SERVER(inode)->nfs_client->rpc_ops;
  214. }
  215. static inline unsigned NFS_MINATTRTIMEO(const struct inode *inode)
  216. {
  217. struct nfs_server *nfss = NFS_SERVER(inode);
  218. return S_ISDIR(inode->i_mode) ? nfss->acdirmin : nfss->acregmin;
  219. }
  220. static inline unsigned NFS_MAXATTRTIMEO(const struct inode *inode)
  221. {
  222. struct nfs_server *nfss = NFS_SERVER(inode);
  223. return S_ISDIR(inode->i_mode) ? nfss->acdirmax : nfss->acregmax;
  224. }
  225. static inline int NFS_STALE(const struct inode *inode)
  226. {
  227. return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
  228. }
  229. static inline int NFS_FSCACHE(const struct inode *inode)
  230. {
  231. return test_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
  232. }
  233. static inline __u64 NFS_FILEID(const struct inode *inode)
  234. {
  235. return NFS_I(inode)->fileid;
  236. }
  237. static inline void set_nfs_fileid(struct inode *inode, __u64 fileid)
  238. {
  239. NFS_I(inode)->fileid = fileid;
  240. }
  241. static inline void nfs_mark_for_revalidate(struct inode *inode)
  242. {
  243. struct nfs_inode *nfsi = NFS_I(inode);
  244. spin_lock(&inode->i_lock);
  245. nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS;
  246. if (S_ISDIR(inode->i_mode))
  247. nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA;
  248. spin_unlock(&inode->i_lock);
  249. }
  250. static inline int nfs_server_capable(struct inode *inode, int cap)
  251. {
  252. return NFS_SERVER(inode)->caps & cap;
  253. }
  254. static inline void nfs_set_verifier(struct dentry * dentry, unsigned long verf)
  255. {
  256. dentry->d_time = verf;
  257. }
  258. /**
  259. * nfs_save_change_attribute - Returns the inode attribute change cookie
  260. * @dir - pointer to parent directory inode
  261. * The "change attribute" is updated every time we finish an operation
  262. * that will result in a metadata change on the server.
  263. */
  264. static inline unsigned long nfs_save_change_attribute(struct inode *dir)
  265. {
  266. return NFS_I(dir)->cache_change_attribute;
  267. }
  268. /**
  269. * nfs_verify_change_attribute - Detects NFS remote directory changes
  270. * @dir - pointer to parent directory inode
  271. * @chattr - previously saved change attribute
  272. * Return "false" if the verifiers doesn't match the change attribute.
  273. * This would usually indicate that the directory contents have changed on
  274. * the server, and that any dentries need revalidating.
  275. */
  276. static inline int nfs_verify_change_attribute(struct inode *dir, unsigned long chattr)
  277. {
  278. return chattr == NFS_I(dir)->cache_change_attribute;
  279. }
  280. /*
  281. * linux/fs/nfs/inode.c
  282. */
  283. extern int nfs_sync_mapping(struct address_space *mapping);
  284. extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
  285. extern void nfs_zap_caches(struct inode *);
  286. extern void nfs_invalidate_atime(struct inode *);
  287. extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
  288. struct nfs_fattr *);
  289. extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
  290. extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
  291. extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
  292. extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
  293. extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *);
  294. extern void nfs_access_set_mask(struct nfs_access_entry *, u32);
  295. extern int nfs_permission(struct inode *, int);
  296. extern int nfs_open(struct inode *, struct file *);
  297. extern int nfs_release(struct inode *, struct file *);
  298. extern int nfs_attribute_timeout(struct inode *inode);
  299. extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
  300. extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
  301. extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
  302. extern int nfs_setattr(struct dentry *, struct iattr *);
  303. extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
  304. extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
  305. extern void put_nfs_open_context(struct nfs_open_context *ctx);
  306. extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode);
  307. extern struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode);
  308. extern void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx);
  309. extern struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx);
  310. extern void nfs_put_lock_context(struct nfs_lock_context *l_ctx);
  311. extern u64 nfs_compat_user_ino64(u64 fileid);
  312. extern void nfs_fattr_init(struct nfs_fattr *fattr);
  313. extern unsigned long nfs_inc_attr_generation_counter(void);
  314. extern struct nfs_fattr *nfs_alloc_fattr(void);
  315. static inline void nfs_free_fattr(const struct nfs_fattr *fattr)
  316. {
  317. kfree(fattr);
  318. }
  319. extern struct nfs_fh *nfs_alloc_fhandle(void);
  320. static inline void nfs_free_fhandle(const struct nfs_fh *fh)
  321. {
  322. kfree(fh);
  323. }
  324. #ifdef NFS_DEBUG
  325. extern u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh);
  326. static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
  327. {
  328. return _nfs_display_fhandle_hash(fh);
  329. }
  330. extern void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption);
  331. #define nfs_display_fhandle(fh, caption) \
  332. do { \
  333. if (unlikely(nfs_debug & NFSDBG_FACILITY)) \
  334. _nfs_display_fhandle(fh, caption); \
  335. } while (0)
  336. #else
  337. static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
  338. {
  339. return 0;
  340. }
  341. static inline void nfs_display_fhandle(const struct nfs_fh *fh,
  342. const char *caption)
  343. {
  344. }
  345. #endif
  346. /*
  347. * linux/fs/nfs/nfsroot.c
  348. */
  349. extern int nfs_root_data(char **root_device, char **root_data); /*__init*/
  350. /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
  351. extern __be32 root_nfs_parse_addr(char *name); /*__init*/
  352. /*
  353. * linux/fs/nfs/file.c
  354. */
  355. extern const struct file_operations nfs_file_operations;
  356. #if IS_ENABLED(CONFIG_NFS_V4)
  357. extern const struct file_operations nfs4_file_operations;
  358. #endif /* CONFIG_NFS_V4 */
  359. extern const struct address_space_operations nfs_file_aops;
  360. extern const struct address_space_operations nfs_dir_aops;
  361. static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
  362. {
  363. return filp->private_data;
  364. }
  365. static inline struct rpc_cred *nfs_file_cred(struct file *file)
  366. {
  367. if (file != NULL) {
  368. struct nfs_open_context *ctx =
  369. nfs_file_open_context(file);
  370. if (ctx)
  371. return ctx->cred;
  372. }
  373. return NULL;
  374. }
  375. /*
  376. * linux/fs/nfs/xattr.c
  377. */
  378. #ifdef CONFIG_NFS_V3_ACL
  379. extern ssize_t nfs3_listxattr(struct dentry *, char *, size_t);
  380. extern ssize_t nfs3_getxattr(struct dentry *, const char *, void *, size_t);
  381. extern int nfs3_setxattr(struct dentry *, const char *,
  382. const void *, size_t, int);
  383. extern int nfs3_removexattr (struct dentry *, const char *name);
  384. #else
  385. # define nfs3_listxattr NULL
  386. # define nfs3_getxattr NULL
  387. # define nfs3_setxattr NULL
  388. # define nfs3_removexattr NULL
  389. #endif
  390. /*
  391. * linux/fs/nfs/direct.c
  392. */
  393. extern ssize_t nfs_direct_IO(int, struct kiocb *, const struct iovec *, loff_t,
  394. unsigned long);
  395. extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
  396. const struct iovec *iov, unsigned long nr_segs,
  397. loff_t pos, bool uio);
  398. extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
  399. const struct iovec *iov, unsigned long nr_segs,
  400. loff_t pos, bool uio);
  401. /*
  402. * linux/fs/nfs/dir.c
  403. */
  404. extern const struct file_operations nfs_dir_operations;
  405. extern const struct dentry_operations nfs_dentry_operations;
  406. extern void nfs_force_lookup_revalidate(struct inode *dir);
  407. extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh, struct nfs_fattr *fattr);
  408. extern int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags);
  409. extern void nfs_access_zap_cache(struct inode *inode);
  410. /*
  411. * linux/fs/nfs/symlink.c
  412. */
  413. extern const struct inode_operations nfs_symlink_inode_operations;
  414. /*
  415. * linux/fs/nfs/sysctl.c
  416. */
  417. #ifdef CONFIG_SYSCTL
  418. extern int nfs_register_sysctl(void);
  419. extern void nfs_unregister_sysctl(void);
  420. #else
  421. #define nfs_register_sysctl() 0
  422. #define nfs_unregister_sysctl() do { } while(0)
  423. #endif
  424. /*
  425. * linux/fs/nfs/namespace.c
  426. */
  427. extern const struct inode_operations nfs_mountpoint_inode_operations;
  428. extern const struct inode_operations nfs_referral_inode_operations;
  429. extern int nfs_mountpoint_expiry_timeout;
  430. extern void nfs_release_automount_timer(void);
  431. /*
  432. * linux/fs/nfs/unlink.c
  433. */
  434. extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
  435. extern void nfs_block_sillyrename(struct dentry *dentry);
  436. extern void nfs_unblock_sillyrename(struct dentry *dentry);
  437. extern int nfs_sillyrename(struct inode *dir, struct dentry *dentry);
  438. /*
  439. * linux/fs/nfs/write.c
  440. */
  441. extern int nfs_congestion_kb;
  442. extern int nfs_writepage(struct page *page, struct writeback_control *wbc);
  443. extern int nfs_writepages(struct address_space *, struct writeback_control *);
  444. extern int nfs_flush_incompatible(struct file *file, struct page *page);
  445. extern int nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
  446. extern void nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
  447. /*
  448. * Try to write back everything synchronously (but check the
  449. * return value!)
  450. */
  451. extern int nfs_wb_all(struct inode *inode);
  452. extern int nfs_wb_page(struct inode *inode, struct page* page);
  453. extern int nfs_wb_page_cancel(struct inode *inode, struct page* page);
  454. #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
  455. extern int nfs_commit_inode(struct inode *, int);
  456. extern struct nfs_commit_data *nfs_commitdata_alloc(void);
  457. extern void nfs_commit_free(struct nfs_commit_data *data);
  458. #else
  459. static inline int
  460. nfs_commit_inode(struct inode *inode, int how)
  461. {
  462. return 0;
  463. }
  464. #endif
  465. static inline int
  466. nfs_have_writebacks(struct inode *inode)
  467. {
  468. return NFS_I(inode)->npages != 0;
  469. }
  470. /*
  471. * linux/fs/nfs/read.c
  472. */
  473. extern int nfs_readpage(struct file *, struct page *);
  474. extern int nfs_readpages(struct file *, struct address_space *,
  475. struct list_head *, unsigned);
  476. extern int nfs_readpage_result(struct rpc_task *, struct nfs_read_data *);
  477. extern int nfs_readpage_async(struct nfs_open_context *, struct inode *,
  478. struct page *);
  479. /*
  480. * linux/fs/nfs3proc.c
  481. */
  482. #ifdef CONFIG_NFS_V3_ACL
  483. extern struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type);
  484. extern int nfs3_proc_setacl(struct inode *inode, int type,
  485. struct posix_acl *acl);
  486. extern int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode,
  487. umode_t mode);
  488. extern void nfs3_forget_cached_acls(struct inode *inode);
  489. #else
  490. static inline int nfs3_proc_set_default_acl(struct inode *dir,
  491. struct inode *inode,
  492. umode_t mode)
  493. {
  494. return 0;
  495. }
  496. static inline void nfs3_forget_cached_acls(struct inode *inode)
  497. {
  498. }
  499. #endif /* CONFIG_NFS_V3_ACL */
  500. /*
  501. * inline functions
  502. */
  503. static inline loff_t nfs_size_to_loff_t(__u64 size)
  504. {
  505. if (size > (__u64) OFFSET_MAX - 1)
  506. return OFFSET_MAX - 1;
  507. return (loff_t) size;
  508. }
  509. static inline ino_t
  510. nfs_fileid_to_ino_t(u64 fileid)
  511. {
  512. ino_t ino = (ino_t) fileid;
  513. if (sizeof(ino_t) < sizeof(u64))
  514. ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
  515. return ino;
  516. }
  517. #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
  518. # undef ifdebug
  519. # ifdef NFS_DEBUG
  520. # define ifdebug(fac) if (unlikely(nfs_debug & NFSDBG_##fac))
  521. # define NFS_IFDEBUG(x) x
  522. # else
  523. # define ifdebug(fac) if (0)
  524. # define NFS_IFDEBUG(x)
  525. # endif
  526. #endif