fs.h 73 KB

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  1. #ifndef _LINUX_FS_H
  2. #define _LINUX_FS_H
  3. /*
  4. * This file has definitions for some important file table
  5. * structures etc.
  6. */
  7. #include <linux/limits.h>
  8. #include <linux/ioctl.h>
  9. /*
  10. * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
  11. * the file limit at runtime and only root can increase the per-process
  12. * nr_file rlimit, so it's safe to set up a ridiculously high absolute
  13. * upper limit on files-per-process.
  14. *
  15. * Some programs (notably those using select()) may have to be
  16. * recompiled to take full advantage of the new limits..
  17. */
  18. /* Fixed constants first: */
  19. #undef NR_OPEN
  20. extern int sysctl_nr_open;
  21. #define INR_OPEN 1024 /* Initial setting for nfile rlimits */
  22. #define BLOCK_SIZE_BITS 10
  23. #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
  24. #define SEEK_SET 0 /* seek relative to beginning of file */
  25. #define SEEK_CUR 1 /* seek relative to current file position */
  26. #define SEEK_END 2 /* seek relative to end of file */
  27. #define SEEK_MAX SEEK_END
  28. /* And dynamically-tunable limits and defaults: */
  29. struct files_stat_struct {
  30. int nr_files; /* read only */
  31. int nr_free_files; /* read only */
  32. int max_files; /* tunable */
  33. };
  34. extern struct files_stat_struct files_stat;
  35. extern int get_max_files(void);
  36. struct inodes_stat_t {
  37. int nr_inodes;
  38. int nr_unused;
  39. int dummy[5]; /* padding for sysctl ABI compatibility */
  40. };
  41. extern struct inodes_stat_t inodes_stat;
  42. extern int leases_enable, lease_break_time;
  43. #ifdef CONFIG_DNOTIFY
  44. extern int dir_notify_enable;
  45. #endif
  46. #define NR_FILE 8192 /* this can well be larger on a larger system */
  47. #define MAY_EXEC 1
  48. #define MAY_WRITE 2
  49. #define MAY_READ 4
  50. #define MAY_APPEND 8
  51. #define FMODE_READ 1
  52. #define FMODE_WRITE 2
  53. /* Internal kernel extensions */
  54. #define FMODE_LSEEK 4
  55. #define FMODE_PREAD 8
  56. #define FMODE_PWRITE FMODE_PREAD /* These go hand in hand */
  57. /* File is being opened for execution. Primary users of this flag are
  58. distributed filesystems that can use it to achieve correct ETXTBUSY
  59. behavior for cross-node execution/opening_for_writing of files */
  60. #define FMODE_EXEC 16
  61. #define RW_MASK 1
  62. #define RWA_MASK 2
  63. #define READ 0
  64. #define WRITE 1
  65. #define READA 2 /* read-ahead - don't block if no resources */
  66. #define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */
  67. #define READ_SYNC (READ | (1 << BIO_RW_SYNC))
  68. #define READ_META (READ | (1 << BIO_RW_META))
  69. #define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC))
  70. #define WRITE_BARRIER ((1 << BIO_RW) | (1 << BIO_RW_BARRIER))
  71. #define SEL_IN 1
  72. #define SEL_OUT 2
  73. #define SEL_EX 4
  74. /* public flags for file_system_type */
  75. #define FS_REQUIRES_DEV 1
  76. #define FS_BINARY_MOUNTDATA 2
  77. #define FS_HAS_SUBTYPE 4
  78. #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
  79. #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move()
  80. * during rename() internally.
  81. */
  82. /*
  83. * These are the fs-independent mount-flags: up to 32 flags are supported
  84. */
  85. #define MS_RDONLY 1 /* Mount read-only */
  86. #define MS_NOSUID 2 /* Ignore suid and sgid bits */
  87. #define MS_NODEV 4 /* Disallow access to device special files */
  88. #define MS_NOEXEC 8 /* Disallow program execution */
  89. #define MS_SYNCHRONOUS 16 /* Writes are synced at once */
  90. #define MS_REMOUNT 32 /* Alter flags of a mounted FS */
  91. #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
  92. #define MS_DIRSYNC 128 /* Directory modifications are synchronous */
  93. #define MS_NOATIME 1024 /* Do not update access times. */
  94. #define MS_NODIRATIME 2048 /* Do not update directory access times */
  95. #define MS_BIND 4096
  96. #define MS_MOVE 8192
  97. #define MS_REC 16384
  98. #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence.
  99. MS_VERBOSE is deprecated. */
  100. #define MS_SILENT 32768
  101. #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
  102. #define MS_UNBINDABLE (1<<17) /* change to unbindable */
  103. #define MS_PRIVATE (1<<18) /* change to private */
  104. #define MS_SLAVE (1<<19) /* change to slave */
  105. #define MS_SHARED (1<<20) /* change to shared */
  106. #define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */
  107. #define MS_KERNMOUNT (1<<22) /* this is a kern_mount call */
  108. #define MS_I_VERSION (1<<23) /* Update inode I_version field */
  109. #define MS_ACTIVE (1<<30)
  110. #define MS_NOUSER (1<<31)
  111. /*
  112. * Superblock flags that can be altered by MS_REMOUNT
  113. */
  114. #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK)
  115. /*
  116. * Old magic mount flag and mask
  117. */
  118. #define MS_MGC_VAL 0xC0ED0000
  119. #define MS_MGC_MSK 0xffff0000
  120. /* Inode flags - they have nothing to superblock flags now */
  121. #define S_SYNC 1 /* Writes are synced at once */
  122. #define S_NOATIME 2 /* Do not update access times */
  123. #define S_APPEND 4 /* Append-only file */
  124. #define S_IMMUTABLE 8 /* Immutable file */
  125. #define S_DEAD 16 /* removed, but still open directory */
  126. #define S_NOQUOTA 32 /* Inode is not counted to quota */
  127. #define S_DIRSYNC 64 /* Directory modifications are synchronous */
  128. #define S_NOCMTIME 128 /* Do not update file c/mtime */
  129. #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
  130. #define S_PRIVATE 512 /* Inode is fs-internal */
  131. /*
  132. * Note that nosuid etc flags are inode-specific: setting some file-system
  133. * flags just means all the inodes inherit those flags by default. It might be
  134. * possible to override it selectively if you really wanted to with some
  135. * ioctl() that is not currently implemented.
  136. *
  137. * Exception: MS_RDONLY is always applied to the entire file system.
  138. *
  139. * Unfortunately, it is possible to change a filesystems flags with it mounted
  140. * with files in use. This means that all of the inodes will not have their
  141. * i_flags updated. Hence, i_flags no longer inherit the superblock mount
  142. * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
  143. */
  144. #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
  145. #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
  146. #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
  147. ((inode)->i_flags & S_SYNC))
  148. #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
  149. ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
  150. #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
  151. #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
  152. #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION)
  153. #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
  154. #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
  155. #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
  156. #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
  157. #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
  158. #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
  159. #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
  160. #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
  161. /* the read-only stuff doesn't really belong here, but any other place is
  162. probably as bad and I don't want to create yet another include file. */
  163. #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
  164. #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
  165. #define BLKRRPART _IO(0x12,95) /* re-read partition table */
  166. #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
  167. #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
  168. #define BLKRASET _IO(0x12,98) /* set read ahead for block device */
  169. #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
  170. #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
  171. #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
  172. #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
  173. #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
  174. #define BLKSSZGET _IO(0x12,104)/* get block device sector size */
  175. #if 0
  176. #define BLKPG _IO(0x12,105)/* See blkpg.h */
  177. /* Some people are morons. Do not use sizeof! */
  178. #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
  179. #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
  180. /* This was here just to show that the number is taken -
  181. probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
  182. #endif
  183. /* A jump here: 108-111 have been used for various private purposes. */
  184. #define BLKBSZGET _IOR(0x12,112,size_t)
  185. #define BLKBSZSET _IOW(0x12,113,size_t)
  186. #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
  187. #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
  188. #define BLKTRACESTART _IO(0x12,116)
  189. #define BLKTRACESTOP _IO(0x12,117)
  190. #define BLKTRACETEARDOWN _IO(0x12,118)
  191. #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
  192. #define FIBMAP _IO(0x00,1) /* bmap access */
  193. #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
  194. #define FS_IOC_GETFLAGS _IOR('f', 1, long)
  195. #define FS_IOC_SETFLAGS _IOW('f', 2, long)
  196. #define FS_IOC_GETVERSION _IOR('v', 1, long)
  197. #define FS_IOC_SETVERSION _IOW('v', 2, long)
  198. #define FS_IOC32_GETFLAGS _IOR('f', 1, int)
  199. #define FS_IOC32_SETFLAGS _IOW('f', 2, int)
  200. #define FS_IOC32_GETVERSION _IOR('v', 1, int)
  201. #define FS_IOC32_SETVERSION _IOW('v', 2, int)
  202. /*
  203. * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
  204. */
  205. #define FS_SECRM_FL 0x00000001 /* Secure deletion */
  206. #define FS_UNRM_FL 0x00000002 /* Undelete */
  207. #define FS_COMPR_FL 0x00000004 /* Compress file */
  208. #define FS_SYNC_FL 0x00000008 /* Synchronous updates */
  209. #define FS_IMMUTABLE_FL 0x00000010 /* Immutable file */
  210. #define FS_APPEND_FL 0x00000020 /* writes to file may only append */
  211. #define FS_NODUMP_FL 0x00000040 /* do not dump file */
  212. #define FS_NOATIME_FL 0x00000080 /* do not update atime */
  213. /* Reserved for compression usage... */
  214. #define FS_DIRTY_FL 0x00000100
  215. #define FS_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
  216. #define FS_NOCOMP_FL 0x00000400 /* Don't compress */
  217. #define FS_ECOMPR_FL 0x00000800 /* Compression error */
  218. /* End compression flags --- maybe not all used */
  219. #define FS_BTREE_FL 0x00001000 /* btree format dir */
  220. #define FS_INDEX_FL 0x00001000 /* hash-indexed directory */
  221. #define FS_IMAGIC_FL 0x00002000 /* AFS directory */
  222. #define FS_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
  223. #define FS_NOTAIL_FL 0x00008000 /* file tail should not be merged */
  224. #define FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
  225. #define FS_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
  226. #define FS_EXTENT_FL 0x00080000 /* Extents */
  227. #define FS_DIRECTIO_FL 0x00100000 /* Use direct i/o */
  228. #define FS_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
  229. #define FS_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
  230. #define FS_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
  231. #define SYNC_FILE_RANGE_WAIT_BEFORE 1
  232. #define SYNC_FILE_RANGE_WRITE 2
  233. #define SYNC_FILE_RANGE_WAIT_AFTER 4
  234. #ifdef __KERNEL__
  235. #include <linux/linkage.h>
  236. #include <linux/wait.h>
  237. #include <linux/types.h>
  238. #include <linux/kdev_t.h>
  239. #include <linux/dcache.h>
  240. #include <linux/namei.h>
  241. #include <linux/stat.h>
  242. #include <linux/cache.h>
  243. #include <linux/kobject.h>
  244. #include <linux/list.h>
  245. #include <linux/radix-tree.h>
  246. #include <linux/prio_tree.h>
  247. #include <linux/init.h>
  248. #include <linux/pid.h>
  249. #include <linux/mutex.h>
  250. #include <linux/capability.h>
  251. #include <asm/atomic.h>
  252. #include <asm/semaphore.h>
  253. #include <asm/byteorder.h>
  254. struct export_operations;
  255. struct hd_geometry;
  256. struct iovec;
  257. struct nameidata;
  258. struct kiocb;
  259. struct pipe_inode_info;
  260. struct poll_table_struct;
  261. struct kstatfs;
  262. struct vm_area_struct;
  263. struct vfsmount;
  264. extern void __init inode_init(void);
  265. extern void __init inode_init_early(void);
  266. extern void __init mnt_init(void);
  267. extern void __init files_init(unsigned long);
  268. struct buffer_head;
  269. typedef int (get_block_t)(struct inode *inode, sector_t iblock,
  270. struct buffer_head *bh_result, int create);
  271. typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
  272. ssize_t bytes, void *private);
  273. /*
  274. * Attribute flags. These should be or-ed together to figure out what
  275. * has been changed!
  276. */
  277. #define ATTR_MODE 1
  278. #define ATTR_UID 2
  279. #define ATTR_GID 4
  280. #define ATTR_SIZE 8
  281. #define ATTR_ATIME 16
  282. #define ATTR_MTIME 32
  283. #define ATTR_CTIME 64
  284. #define ATTR_ATIME_SET 128
  285. #define ATTR_MTIME_SET 256
  286. #define ATTR_FORCE 512 /* Not a change, but a change it */
  287. #define ATTR_ATTR_FLAG 1024
  288. #define ATTR_KILL_SUID 2048
  289. #define ATTR_KILL_SGID 4096
  290. #define ATTR_FILE 8192
  291. #define ATTR_KILL_PRIV 16384
  292. #define ATTR_OPEN 32768 /* Truncating from open(O_TRUNC) */
  293. /*
  294. * This is the Inode Attributes structure, used for notify_change(). It
  295. * uses the above definitions as flags, to know which values have changed.
  296. * Also, in this manner, a Filesystem can look at only the values it cares
  297. * about. Basically, these are the attributes that the VFS layer can
  298. * request to change from the FS layer.
  299. *
  300. * Derek Atkins <warlord@MIT.EDU> 94-10-20
  301. */
  302. struct iattr {
  303. unsigned int ia_valid;
  304. umode_t ia_mode;
  305. uid_t ia_uid;
  306. gid_t ia_gid;
  307. loff_t ia_size;
  308. struct timespec ia_atime;
  309. struct timespec ia_mtime;
  310. struct timespec ia_ctime;
  311. /*
  312. * Not an attribute, but an auxilary info for filesystems wanting to
  313. * implement an ftruncate() like method. NOTE: filesystem should
  314. * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
  315. */
  316. struct file *ia_file;
  317. };
  318. /*
  319. * Includes for diskquotas.
  320. */
  321. #include <linux/quota.h>
  322. /**
  323. * enum positive_aop_returns - aop return codes with specific semantics
  324. *
  325. * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
  326. * completed, that the page is still locked, and
  327. * should be considered active. The VM uses this hint
  328. * to return the page to the active list -- it won't
  329. * be a candidate for writeback again in the near
  330. * future. Other callers must be careful to unlock
  331. * the page if they get this return. Returned by
  332. * writepage();
  333. *
  334. * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
  335. * unlocked it and the page might have been truncated.
  336. * The caller should back up to acquiring a new page and
  337. * trying again. The aop will be taking reasonable
  338. * precautions not to livelock. If the caller held a page
  339. * reference, it should drop it before retrying. Returned
  340. * by readpage().
  341. *
  342. * address_space_operation functions return these large constants to indicate
  343. * special semantics to the caller. These are much larger than the bytes in a
  344. * page to allow for functions that return the number of bytes operated on in a
  345. * given page.
  346. */
  347. enum positive_aop_returns {
  348. AOP_WRITEPAGE_ACTIVATE = 0x80000,
  349. AOP_TRUNCATED_PAGE = 0x80001,
  350. };
  351. #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */
  352. #define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */
  353. /*
  354. * oh the beauties of C type declarations.
  355. */
  356. struct page;
  357. struct address_space;
  358. struct writeback_control;
  359. struct iov_iter {
  360. const struct iovec *iov;
  361. unsigned long nr_segs;
  362. size_t iov_offset;
  363. size_t count;
  364. };
  365. size_t iov_iter_copy_from_user_atomic(struct page *page,
  366. struct iov_iter *i, unsigned long offset, size_t bytes);
  367. size_t iov_iter_copy_from_user(struct page *page,
  368. struct iov_iter *i, unsigned long offset, size_t bytes);
  369. void iov_iter_advance(struct iov_iter *i, size_t bytes);
  370. int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes);
  371. size_t iov_iter_single_seg_count(struct iov_iter *i);
  372. static inline void iov_iter_init(struct iov_iter *i,
  373. const struct iovec *iov, unsigned long nr_segs,
  374. size_t count, size_t written)
  375. {
  376. i->iov = iov;
  377. i->nr_segs = nr_segs;
  378. i->iov_offset = 0;
  379. i->count = count + written;
  380. iov_iter_advance(i, written);
  381. }
  382. static inline size_t iov_iter_count(struct iov_iter *i)
  383. {
  384. return i->count;
  385. }
  386. struct address_space_operations {
  387. int (*writepage)(struct page *page, struct writeback_control *wbc);
  388. int (*readpage)(struct file *, struct page *);
  389. void (*sync_page)(struct page *);
  390. /* Write back some dirty pages from this mapping. */
  391. int (*writepages)(struct address_space *, struct writeback_control *);
  392. /* Set a page dirty. Return true if this dirtied it */
  393. int (*set_page_dirty)(struct page *page);
  394. int (*readpages)(struct file *filp, struct address_space *mapping,
  395. struct list_head *pages, unsigned nr_pages);
  396. /*
  397. * ext3 requires that a successful prepare_write() call be followed
  398. * by a commit_write() call - they must be balanced
  399. */
  400. int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
  401. int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
  402. int (*write_begin)(struct file *, struct address_space *mapping,
  403. loff_t pos, unsigned len, unsigned flags,
  404. struct page **pagep, void **fsdata);
  405. int (*write_end)(struct file *, struct address_space *mapping,
  406. loff_t pos, unsigned len, unsigned copied,
  407. struct page *page, void *fsdata);
  408. /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
  409. sector_t (*bmap)(struct address_space *, sector_t);
  410. void (*invalidatepage) (struct page *, unsigned long);
  411. int (*releasepage) (struct page *, gfp_t);
  412. ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
  413. loff_t offset, unsigned long nr_segs);
  414. struct page* (*get_xip_page)(struct address_space *, sector_t,
  415. int);
  416. /* migrate the contents of a page to the specified target */
  417. int (*migratepage) (struct address_space *,
  418. struct page *, struct page *);
  419. int (*launder_page) (struct page *);
  420. };
  421. /*
  422. * pagecache_write_begin/pagecache_write_end must be used by general code
  423. * to write into the pagecache.
  424. */
  425. int pagecache_write_begin(struct file *, struct address_space *mapping,
  426. loff_t pos, unsigned len, unsigned flags,
  427. struct page **pagep, void **fsdata);
  428. int pagecache_write_end(struct file *, struct address_space *mapping,
  429. loff_t pos, unsigned len, unsigned copied,
  430. struct page *page, void *fsdata);
  431. struct backing_dev_info;
  432. struct address_space {
  433. struct inode *host; /* owner: inode, block_device */
  434. struct radix_tree_root page_tree; /* radix tree of all pages */
  435. rwlock_t tree_lock; /* and rwlock protecting it */
  436. unsigned int i_mmap_writable;/* count VM_SHARED mappings */
  437. struct prio_tree_root i_mmap; /* tree of private and shared mappings */
  438. struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
  439. spinlock_t i_mmap_lock; /* protect tree, count, list */
  440. unsigned int truncate_count; /* Cover race condition with truncate */
  441. unsigned long nrpages; /* number of total pages */
  442. pgoff_t writeback_index;/* writeback starts here */
  443. const struct address_space_operations *a_ops; /* methods */
  444. unsigned long flags; /* error bits/gfp mask */
  445. struct backing_dev_info *backing_dev_info; /* device readahead, etc */
  446. spinlock_t private_lock; /* for use by the address_space */
  447. struct list_head private_list; /* ditto */
  448. struct address_space *assoc_mapping; /* ditto */
  449. } __attribute__((aligned(sizeof(long))));
  450. /*
  451. * On most architectures that alignment is already the case; but
  452. * must be enforced here for CRIS, to let the least signficant bit
  453. * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
  454. */
  455. struct block_device {
  456. dev_t bd_dev; /* not a kdev_t - it's a search key */
  457. struct inode * bd_inode; /* will die */
  458. int bd_openers;
  459. struct mutex bd_mutex; /* open/close mutex */
  460. struct semaphore bd_mount_sem;
  461. struct list_head bd_inodes;
  462. void * bd_holder;
  463. int bd_holders;
  464. #ifdef CONFIG_SYSFS
  465. struct list_head bd_holder_list;
  466. #endif
  467. struct block_device * bd_contains;
  468. unsigned bd_block_size;
  469. struct hd_struct * bd_part;
  470. /* number of times partitions within this device have been opened. */
  471. unsigned bd_part_count;
  472. int bd_invalidated;
  473. struct gendisk * bd_disk;
  474. struct list_head bd_list;
  475. struct backing_dev_info *bd_inode_backing_dev_info;
  476. /*
  477. * Private data. You must have bd_claim'ed the block_device
  478. * to use this. NOTE: bd_claim allows an owner to claim
  479. * the same device multiple times, the owner must take special
  480. * care to not mess up bd_private for that case.
  481. */
  482. unsigned long bd_private;
  483. };
  484. /*
  485. * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
  486. * radix trees
  487. */
  488. #define PAGECACHE_TAG_DIRTY 0
  489. #define PAGECACHE_TAG_WRITEBACK 1
  490. int mapping_tagged(struct address_space *mapping, int tag);
  491. /*
  492. * Might pages of this file be mapped into userspace?
  493. */
  494. static inline int mapping_mapped(struct address_space *mapping)
  495. {
  496. return !prio_tree_empty(&mapping->i_mmap) ||
  497. !list_empty(&mapping->i_mmap_nonlinear);
  498. }
  499. /*
  500. * Might pages of this file have been modified in userspace?
  501. * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
  502. * marks vma as VM_SHARED if it is shared, and the file was opened for
  503. * writing i.e. vma may be mprotected writable even if now readonly.
  504. */
  505. static inline int mapping_writably_mapped(struct address_space *mapping)
  506. {
  507. return mapping->i_mmap_writable != 0;
  508. }
  509. /*
  510. * Use sequence counter to get consistent i_size on 32-bit processors.
  511. */
  512. #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  513. #include <linux/seqlock.h>
  514. #define __NEED_I_SIZE_ORDERED
  515. #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
  516. #else
  517. #define i_size_ordered_init(inode) do { } while (0)
  518. #endif
  519. struct inode {
  520. struct hlist_node i_hash;
  521. struct list_head i_list;
  522. struct list_head i_sb_list;
  523. struct list_head i_dentry;
  524. unsigned long i_ino;
  525. atomic_t i_count;
  526. unsigned int i_nlink;
  527. uid_t i_uid;
  528. gid_t i_gid;
  529. dev_t i_rdev;
  530. u64 i_version;
  531. loff_t i_size;
  532. #ifdef __NEED_I_SIZE_ORDERED
  533. seqcount_t i_size_seqcount;
  534. #endif
  535. struct timespec i_atime;
  536. struct timespec i_mtime;
  537. struct timespec i_ctime;
  538. unsigned int i_blkbits;
  539. blkcnt_t i_blocks;
  540. unsigned short i_bytes;
  541. umode_t i_mode;
  542. spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
  543. struct mutex i_mutex;
  544. struct rw_semaphore i_alloc_sem;
  545. const struct inode_operations *i_op;
  546. const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
  547. struct super_block *i_sb;
  548. struct file_lock *i_flock;
  549. struct address_space *i_mapping;
  550. struct address_space i_data;
  551. #ifdef CONFIG_QUOTA
  552. struct dquot *i_dquot[MAXQUOTAS];
  553. #endif
  554. struct list_head i_devices;
  555. union {
  556. struct pipe_inode_info *i_pipe;
  557. struct block_device *i_bdev;
  558. struct cdev *i_cdev;
  559. };
  560. int i_cindex;
  561. __u32 i_generation;
  562. #ifdef CONFIG_DNOTIFY
  563. unsigned long i_dnotify_mask; /* Directory notify events */
  564. struct dnotify_struct *i_dnotify; /* for directory notifications */
  565. #endif
  566. #ifdef CONFIG_INOTIFY
  567. struct list_head inotify_watches; /* watches on this inode */
  568. struct mutex inotify_mutex; /* protects the watches list */
  569. #endif
  570. unsigned long i_state;
  571. unsigned long dirtied_when; /* jiffies of first dirtying */
  572. unsigned int i_flags;
  573. atomic_t i_writecount;
  574. #ifdef CONFIG_SECURITY
  575. void *i_security;
  576. #endif
  577. void *i_private; /* fs or device private pointer */
  578. };
  579. /*
  580. * inode->i_mutex nesting subclasses for the lock validator:
  581. *
  582. * 0: the object of the current VFS operation
  583. * 1: parent
  584. * 2: child/target
  585. * 3: quota file
  586. *
  587. * The locking order between these classes is
  588. * parent -> child -> normal -> xattr -> quota
  589. */
  590. enum inode_i_mutex_lock_class
  591. {
  592. I_MUTEX_NORMAL,
  593. I_MUTEX_PARENT,
  594. I_MUTEX_CHILD,
  595. I_MUTEX_XATTR,
  596. I_MUTEX_QUOTA
  597. };
  598. extern void inode_double_lock(struct inode *inode1, struct inode *inode2);
  599. extern void inode_double_unlock(struct inode *inode1, struct inode *inode2);
  600. /*
  601. * NOTE: in a 32bit arch with a preemptable kernel and
  602. * an UP compile the i_size_read/write must be atomic
  603. * with respect to the local cpu (unlike with preempt disabled),
  604. * but they don't need to be atomic with respect to other cpus like in
  605. * true SMP (so they need either to either locally disable irq around
  606. * the read or for example on x86 they can be still implemented as a
  607. * cmpxchg8b without the need of the lock prefix). For SMP compiles
  608. * and 64bit archs it makes no difference if preempt is enabled or not.
  609. */
  610. static inline loff_t i_size_read(const struct inode *inode)
  611. {
  612. #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  613. loff_t i_size;
  614. unsigned int seq;
  615. do {
  616. seq = read_seqcount_begin(&inode->i_size_seqcount);
  617. i_size = inode->i_size;
  618. } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
  619. return i_size;
  620. #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
  621. loff_t i_size;
  622. preempt_disable();
  623. i_size = inode->i_size;
  624. preempt_enable();
  625. return i_size;
  626. #else
  627. return inode->i_size;
  628. #endif
  629. }
  630. /*
  631. * NOTE: unlike i_size_read(), i_size_write() does need locking around it
  632. * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
  633. * can be lost, resulting in subsequent i_size_read() calls spinning forever.
  634. */
  635. static inline void i_size_write(struct inode *inode, loff_t i_size)
  636. {
  637. #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  638. write_seqcount_begin(&inode->i_size_seqcount);
  639. inode->i_size = i_size;
  640. write_seqcount_end(&inode->i_size_seqcount);
  641. #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
  642. preempt_disable();
  643. inode->i_size = i_size;
  644. preempt_enable();
  645. #else
  646. inode->i_size = i_size;
  647. #endif
  648. }
  649. static inline unsigned iminor(const struct inode *inode)
  650. {
  651. return MINOR(inode->i_rdev);
  652. }
  653. static inline unsigned imajor(const struct inode *inode)
  654. {
  655. return MAJOR(inode->i_rdev);
  656. }
  657. extern struct block_device *I_BDEV(struct inode *inode);
  658. struct fown_struct {
  659. rwlock_t lock; /* protects pid, uid, euid fields */
  660. struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
  661. enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
  662. uid_t uid, euid; /* uid/euid of process setting the owner */
  663. int signum; /* posix.1b rt signal to be delivered on IO */
  664. };
  665. /*
  666. * Track a single file's readahead state
  667. */
  668. struct file_ra_state {
  669. pgoff_t start; /* where readahead started */
  670. unsigned int size; /* # of readahead pages */
  671. unsigned int async_size; /* do asynchronous readahead when
  672. there are only # of pages ahead */
  673. unsigned int ra_pages; /* Maximum readahead window */
  674. int mmap_miss; /* Cache miss stat for mmap accesses */
  675. loff_t prev_pos; /* Cache last read() position */
  676. };
  677. /*
  678. * Check if @index falls in the readahead windows.
  679. */
  680. static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
  681. {
  682. return (index >= ra->start &&
  683. index < ra->start + ra->size);
  684. }
  685. struct file {
  686. /*
  687. * fu_list becomes invalid after file_free is called and queued via
  688. * fu_rcuhead for RCU freeing
  689. */
  690. union {
  691. struct list_head fu_list;
  692. struct rcu_head fu_rcuhead;
  693. } f_u;
  694. struct path f_path;
  695. #define f_dentry f_path.dentry
  696. #define f_vfsmnt f_path.mnt
  697. const struct file_operations *f_op;
  698. atomic_t f_count;
  699. unsigned int f_flags;
  700. mode_t f_mode;
  701. loff_t f_pos;
  702. struct fown_struct f_owner;
  703. unsigned int f_uid, f_gid;
  704. struct file_ra_state f_ra;
  705. u64 f_version;
  706. #ifdef CONFIG_SECURITY
  707. void *f_security;
  708. #endif
  709. /* needed for tty driver, and maybe others */
  710. void *private_data;
  711. #ifdef CONFIG_EPOLL
  712. /* Used by fs/eventpoll.c to link all the hooks to this file */
  713. struct list_head f_ep_links;
  714. spinlock_t f_ep_lock;
  715. #endif /* #ifdef CONFIG_EPOLL */
  716. struct address_space *f_mapping;
  717. };
  718. extern spinlock_t files_lock;
  719. #define file_list_lock() spin_lock(&files_lock);
  720. #define file_list_unlock() spin_unlock(&files_lock);
  721. #define get_file(x) atomic_inc(&(x)->f_count)
  722. #define file_count(x) atomic_read(&(x)->f_count)
  723. #define MAX_NON_LFS ((1UL<<31) - 1)
  724. /* Page cache limit. The filesystems should put that into their s_maxbytes
  725. limits, otherwise bad things can happen in VM. */
  726. #if BITS_PER_LONG==32
  727. #define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
  728. #elif BITS_PER_LONG==64
  729. #define MAX_LFS_FILESIZE 0x7fffffffffffffffUL
  730. #endif
  731. #define FL_POSIX 1
  732. #define FL_FLOCK 2
  733. #define FL_ACCESS 8 /* not trying to lock, just looking */
  734. #define FL_EXISTS 16 /* when unlocking, test for existence */
  735. #define FL_LEASE 32 /* lease held on this file */
  736. #define FL_CLOSE 64 /* unlock on close */
  737. #define FL_SLEEP 128 /* A blocking lock */
  738. /*
  739. * The POSIX file lock owner is determined by
  740. * the "struct files_struct" in the thread group
  741. * (or NULL for no owner - BSD locks).
  742. *
  743. * Lockd stuffs a "host" pointer into this.
  744. */
  745. typedef struct files_struct *fl_owner_t;
  746. struct file_lock_operations {
  747. void (*fl_insert)(struct file_lock *); /* lock insertion callback */
  748. void (*fl_remove)(struct file_lock *); /* lock removal callback */
  749. void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
  750. void (*fl_release_private)(struct file_lock *);
  751. };
  752. struct lock_manager_operations {
  753. int (*fl_compare_owner)(struct file_lock *, struct file_lock *);
  754. void (*fl_notify)(struct file_lock *); /* unblock callback */
  755. int (*fl_grant)(struct file_lock *, struct file_lock *, int);
  756. void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
  757. void (*fl_release_private)(struct file_lock *);
  758. void (*fl_break)(struct file_lock *);
  759. int (*fl_mylease)(struct file_lock *, struct file_lock *);
  760. int (*fl_change)(struct file_lock **, int);
  761. };
  762. /* that will die - we need it for nfs_lock_info */
  763. #include <linux/nfs_fs_i.h>
  764. struct file_lock {
  765. struct file_lock *fl_next; /* singly linked list for this inode */
  766. struct list_head fl_link; /* doubly linked list of all locks */
  767. struct list_head fl_block; /* circular list of blocked processes */
  768. fl_owner_t fl_owner;
  769. unsigned int fl_pid;
  770. struct pid *fl_nspid;
  771. wait_queue_head_t fl_wait;
  772. struct file *fl_file;
  773. unsigned char fl_flags;
  774. unsigned char fl_type;
  775. loff_t fl_start;
  776. loff_t fl_end;
  777. struct fasync_struct * fl_fasync; /* for lease break notifications */
  778. unsigned long fl_break_time; /* for nonblocking lease breaks */
  779. struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
  780. struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
  781. union {
  782. struct nfs_lock_info nfs_fl;
  783. struct nfs4_lock_info nfs4_fl;
  784. struct {
  785. struct list_head link; /* link in AFS vnode's pending_locks list */
  786. int state; /* state of grant or error if -ve */
  787. } afs;
  788. } fl_u;
  789. };
  790. /* The following constant reflects the upper bound of the file/locking space */
  791. #ifndef OFFSET_MAX
  792. #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
  793. #define OFFSET_MAX INT_LIMIT(loff_t)
  794. #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
  795. #endif
  796. #include <linux/fcntl.h>
  797. extern int fcntl_getlk(struct file *, struct flock __user *);
  798. extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
  799. struct flock __user *);
  800. #if BITS_PER_LONG == 32
  801. extern int fcntl_getlk64(struct file *, struct flock64 __user *);
  802. extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
  803. struct flock64 __user *);
  804. #endif
  805. extern void send_sigio(struct fown_struct *fown, int fd, int band);
  806. extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
  807. extern int fcntl_getlease(struct file *filp);
  808. /* fs/sync.c */
  809. extern int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
  810. loff_t endbyte, unsigned int flags);
  811. /* fs/locks.c */
  812. extern void locks_init_lock(struct file_lock *);
  813. extern void locks_copy_lock(struct file_lock *, struct file_lock *);
  814. extern void locks_remove_posix(struct file *, fl_owner_t);
  815. extern void locks_remove_flock(struct file *);
  816. extern void posix_test_lock(struct file *, struct file_lock *);
  817. extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
  818. extern int posix_lock_file_wait(struct file *, struct file_lock *);
  819. extern int posix_unblock_lock(struct file *, struct file_lock *);
  820. extern int vfs_test_lock(struct file *, struct file_lock *);
  821. extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
  822. extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
  823. extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
  824. extern int __break_lease(struct inode *inode, unsigned int flags);
  825. extern void lease_get_mtime(struct inode *, struct timespec *time);
  826. extern int generic_setlease(struct file *, long, struct file_lock **);
  827. extern int vfs_setlease(struct file *, long, struct file_lock **);
  828. extern int lease_modify(struct file_lock **, int);
  829. extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
  830. extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
  831. extern struct seq_operations locks_seq_operations;
  832. struct fasync_struct {
  833. int magic;
  834. int fa_fd;
  835. struct fasync_struct *fa_next; /* singly linked list */
  836. struct file *fa_file;
  837. };
  838. #define FASYNC_MAGIC 0x4601
  839. /* SMP safe fasync helpers: */
  840. extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
  841. /* can be called from interrupts */
  842. extern void kill_fasync(struct fasync_struct **, int, int);
  843. /* only for net: no internal synchronization */
  844. extern void __kill_fasync(struct fasync_struct *, int, int);
  845. extern int __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
  846. extern int f_setown(struct file *filp, unsigned long arg, int force);
  847. extern void f_delown(struct file *filp);
  848. extern pid_t f_getown(struct file *filp);
  849. extern int send_sigurg(struct fown_struct *fown);
  850. /*
  851. * Umount options
  852. */
  853. #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
  854. #define MNT_DETACH 0x00000002 /* Just detach from the tree */
  855. #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
  856. extern struct list_head super_blocks;
  857. extern spinlock_t sb_lock;
  858. #define S_BIAS (1<<30)
  859. struct super_block {
  860. struct list_head s_list; /* Keep this first */
  861. dev_t s_dev; /* search index; _not_ kdev_t */
  862. unsigned long s_blocksize;
  863. unsigned char s_blocksize_bits;
  864. unsigned char s_dirt;
  865. unsigned long long s_maxbytes; /* Max file size */
  866. struct file_system_type *s_type;
  867. const struct super_operations *s_op;
  868. struct dquot_operations *dq_op;
  869. struct quotactl_ops *s_qcop;
  870. const struct export_operations *s_export_op;
  871. unsigned long s_flags;
  872. unsigned long s_magic;
  873. struct dentry *s_root;
  874. struct rw_semaphore s_umount;
  875. struct mutex s_lock;
  876. int s_count;
  877. int s_syncing;
  878. int s_need_sync_fs;
  879. atomic_t s_active;
  880. #ifdef CONFIG_SECURITY
  881. void *s_security;
  882. #endif
  883. struct xattr_handler **s_xattr;
  884. struct list_head s_inodes; /* all inodes */
  885. struct list_head s_dirty; /* dirty inodes */
  886. struct list_head s_io; /* parked for writeback */
  887. struct list_head s_more_io; /* parked for more writeback */
  888. struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */
  889. struct list_head s_files;
  890. struct block_device *s_bdev;
  891. struct mtd_info *s_mtd;
  892. struct list_head s_instances;
  893. struct quota_info s_dquot; /* Diskquota specific options */
  894. int s_frozen;
  895. wait_queue_head_t s_wait_unfrozen;
  896. char s_id[32]; /* Informational name */
  897. void *s_fs_info; /* Filesystem private info */
  898. /*
  899. * The next field is for VFS *only*. No filesystems have any business
  900. * even looking at it. You had been warned.
  901. */
  902. struct mutex s_vfs_rename_mutex; /* Kludge */
  903. /* Granularity of c/m/atime in ns.
  904. Cannot be worse than a second */
  905. u32 s_time_gran;
  906. /*
  907. * Filesystem subtype. If non-empty the filesystem type field
  908. * in /proc/mounts will be "type.subtype"
  909. */
  910. char *s_subtype;
  911. };
  912. extern struct timespec current_fs_time(struct super_block *sb);
  913. /*
  914. * Snapshotting support.
  915. */
  916. enum {
  917. SB_UNFROZEN = 0,
  918. SB_FREEZE_WRITE = 1,
  919. SB_FREEZE_TRANS = 2,
  920. };
  921. #define vfs_check_frozen(sb, level) \
  922. wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level)))
  923. #define get_fs_excl() atomic_inc(&current->fs_excl)
  924. #define put_fs_excl() atomic_dec(&current->fs_excl)
  925. #define has_fs_excl() atomic_read(&current->fs_excl)
  926. #define is_owner_or_cap(inode) \
  927. ((current->fsuid == (inode)->i_uid) || capable(CAP_FOWNER))
  928. /* not quite ready to be deprecated, but... */
  929. extern void lock_super(struct super_block *);
  930. extern void unlock_super(struct super_block *);
  931. /*
  932. * VFS helper functions..
  933. */
  934. extern int vfs_permission(struct nameidata *, int);
  935. extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *);
  936. extern int vfs_mkdir(struct inode *, struct dentry *, int);
  937. extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
  938. extern int vfs_symlink(struct inode *, struct dentry *, const char *, int);
  939. extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
  940. extern int vfs_rmdir(struct inode *, struct dentry *);
  941. extern int vfs_unlink(struct inode *, struct dentry *);
  942. extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
  943. /*
  944. * VFS dentry helper functions.
  945. */
  946. extern void dentry_unhash(struct dentry *dentry);
  947. /*
  948. * VFS file helper functions.
  949. */
  950. extern int file_permission(struct file *, int);
  951. /*
  952. * File types
  953. *
  954. * NOTE! These match bits 12..15 of stat.st_mode
  955. * (ie "(i_mode >> 12) & 15").
  956. */
  957. #define DT_UNKNOWN 0
  958. #define DT_FIFO 1
  959. #define DT_CHR 2
  960. #define DT_DIR 4
  961. #define DT_BLK 6
  962. #define DT_REG 8
  963. #define DT_LNK 10
  964. #define DT_SOCK 12
  965. #define DT_WHT 14
  966. #define OSYNC_METADATA (1<<0)
  967. #define OSYNC_DATA (1<<1)
  968. #define OSYNC_INODE (1<<2)
  969. int generic_osync_inode(struct inode *, struct address_space *, int);
  970. /*
  971. * This is the "filldir" function type, used by readdir() to let
  972. * the kernel specify what kind of dirent layout it wants to have.
  973. * This allows the kernel to read directories into kernel space or
  974. * to have different dirent layouts depending on the binary type.
  975. */
  976. typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
  977. struct block_device_operations {
  978. int (*open) (struct inode *, struct file *);
  979. int (*release) (struct inode *, struct file *);
  980. int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
  981. long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
  982. long (*compat_ioctl) (struct file *, unsigned, unsigned long);
  983. int (*direct_access) (struct block_device *, sector_t, unsigned long *);
  984. int (*media_changed) (struct gendisk *);
  985. int (*revalidate_disk) (struct gendisk *);
  986. int (*getgeo)(struct block_device *, struct hd_geometry *);
  987. struct module *owner;
  988. };
  989. /*
  990. * "descriptor" for what we're up to with a read.
  991. * This allows us to use the same read code yet
  992. * have multiple different users of the data that
  993. * we read from a file.
  994. *
  995. * The simplest case just copies the data to user
  996. * mode.
  997. */
  998. typedef struct {
  999. size_t written;
  1000. size_t count;
  1001. union {
  1002. char __user * buf;
  1003. void *data;
  1004. } arg;
  1005. int error;
  1006. } read_descriptor_t;
  1007. typedef int (*read_actor_t)(read_descriptor_t *, struct page *, unsigned long, unsigned long);
  1008. /* These macros are for out of kernel modules to test that
  1009. * the kernel supports the unlocked_ioctl and compat_ioctl
  1010. * fields in struct file_operations. */
  1011. #define HAVE_COMPAT_IOCTL 1
  1012. #define HAVE_UNLOCKED_IOCTL 1
  1013. /*
  1014. * NOTE:
  1015. * read, write, poll, fsync, readv, writev, unlocked_ioctl and compat_ioctl
  1016. * can be called without the big kernel lock held in all filesystems.
  1017. */
  1018. struct file_operations {
  1019. struct module *owner;
  1020. loff_t (*llseek) (struct file *, loff_t, int);
  1021. ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
  1022. ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
  1023. ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
  1024. ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
  1025. int (*readdir) (struct file *, void *, filldir_t);
  1026. unsigned int (*poll) (struct file *, struct poll_table_struct *);
  1027. int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
  1028. long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
  1029. long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
  1030. int (*mmap) (struct file *, struct vm_area_struct *);
  1031. int (*open) (struct inode *, struct file *);
  1032. int (*flush) (struct file *, fl_owner_t id);
  1033. int (*release) (struct inode *, struct file *);
  1034. int (*fsync) (struct file *, struct dentry *, int datasync);
  1035. int (*aio_fsync) (struct kiocb *, int datasync);
  1036. int (*fasync) (int, struct file *, int);
  1037. int (*lock) (struct file *, int, struct file_lock *);
  1038. ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
  1039. unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
  1040. int (*check_flags)(int);
  1041. int (*dir_notify)(struct file *filp, unsigned long arg);
  1042. int (*flock) (struct file *, int, struct file_lock *);
  1043. ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
  1044. ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
  1045. int (*setlease)(struct file *, long, struct file_lock **);
  1046. };
  1047. struct inode_operations {
  1048. int (*create) (struct inode *,struct dentry *,int, struct nameidata *);
  1049. struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *);
  1050. int (*link) (struct dentry *,struct inode *,struct dentry *);
  1051. int (*unlink) (struct inode *,struct dentry *);
  1052. int (*symlink) (struct inode *,struct dentry *,const char *);
  1053. int (*mkdir) (struct inode *,struct dentry *,int);
  1054. int (*rmdir) (struct inode *,struct dentry *);
  1055. int (*mknod) (struct inode *,struct dentry *,int,dev_t);
  1056. int (*rename) (struct inode *, struct dentry *,
  1057. struct inode *, struct dentry *);
  1058. int (*readlink) (struct dentry *, char __user *,int);
  1059. void * (*follow_link) (struct dentry *, struct nameidata *);
  1060. void (*put_link) (struct dentry *, struct nameidata *, void *);
  1061. void (*truncate) (struct inode *);
  1062. int (*permission) (struct inode *, int, struct nameidata *);
  1063. int (*setattr) (struct dentry *, struct iattr *);
  1064. int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
  1065. int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
  1066. ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
  1067. ssize_t (*listxattr) (struct dentry *, char *, size_t);
  1068. int (*removexattr) (struct dentry *, const char *);
  1069. void (*truncate_range)(struct inode *, loff_t, loff_t);
  1070. long (*fallocate)(struct inode *inode, int mode, loff_t offset,
  1071. loff_t len);
  1072. };
  1073. struct seq_file;
  1074. ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
  1075. unsigned long nr_segs, unsigned long fast_segs,
  1076. struct iovec *fast_pointer,
  1077. struct iovec **ret_pointer);
  1078. extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
  1079. extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
  1080. extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
  1081. unsigned long, loff_t *);
  1082. extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
  1083. unsigned long, loff_t *);
  1084. /*
  1085. * NOTE: write_inode, delete_inode, clear_inode, put_inode can be called
  1086. * without the big kernel lock held in all filesystems.
  1087. */
  1088. struct super_operations {
  1089. struct inode *(*alloc_inode)(struct super_block *sb);
  1090. void (*destroy_inode)(struct inode *);
  1091. void (*read_inode) (struct inode *);
  1092. void (*dirty_inode) (struct inode *);
  1093. int (*write_inode) (struct inode *, int);
  1094. void (*put_inode) (struct inode *);
  1095. void (*drop_inode) (struct inode *);
  1096. void (*delete_inode) (struct inode *);
  1097. void (*put_super) (struct super_block *);
  1098. void (*write_super) (struct super_block *);
  1099. int (*sync_fs)(struct super_block *sb, int wait);
  1100. void (*write_super_lockfs) (struct super_block *);
  1101. void (*unlockfs) (struct super_block *);
  1102. int (*statfs) (struct dentry *, struct kstatfs *);
  1103. int (*remount_fs) (struct super_block *, int *, char *);
  1104. void (*clear_inode) (struct inode *);
  1105. void (*umount_begin) (struct vfsmount *, int);
  1106. int (*show_options)(struct seq_file *, struct vfsmount *);
  1107. int (*show_stats)(struct seq_file *, struct vfsmount *);
  1108. #ifdef CONFIG_QUOTA
  1109. ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
  1110. ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
  1111. #endif
  1112. };
  1113. /*
  1114. * Inode state bits. Protected by inode_lock.
  1115. *
  1116. * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
  1117. * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
  1118. *
  1119. * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
  1120. * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
  1121. * various stages of removing an inode.
  1122. *
  1123. * Two bits are used for locking and completion notification, I_LOCK and I_SYNC.
  1124. *
  1125. * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
  1126. * fdatasync(). i_atime is the usual cause.
  1127. * I_DIRTY_DATASYNC Inode is dirty and must be written on fdatasync(), f.e.
  1128. * because i_size changed.
  1129. * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
  1130. * I_NEW get_new_inode() sets i_state to I_LOCK|I_NEW. Both
  1131. * are cleared by unlock_new_inode(), called from iget().
  1132. * I_WILL_FREE Must be set when calling write_inode_now() if i_count
  1133. * is zero. I_FREEING must be set when I_WILL_FREE is
  1134. * cleared.
  1135. * I_FREEING Set when inode is about to be freed but still has dirty
  1136. * pages or buffers attached or the inode itself is still
  1137. * dirty.
  1138. * I_CLEAR Set by clear_inode(). In this state the inode is clean
  1139. * and can be destroyed.
  1140. *
  1141. * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
  1142. * prohibited for many purposes. iget() must wait for
  1143. * the inode to be completely released, then create it
  1144. * anew. Other functions will just ignore such inodes,
  1145. * if appropriate. I_LOCK is used for waiting.
  1146. *
  1147. * I_LOCK Serves as both a mutex and completion notification.
  1148. * New inodes set I_LOCK. If two processes both create
  1149. * the same inode, one of them will release its inode and
  1150. * wait for I_LOCK to be released before returning.
  1151. * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
  1152. * also cause waiting on I_LOCK, without I_LOCK actually
  1153. * being set. find_inode() uses this to prevent returning
  1154. * nearly-dead inodes.
  1155. * I_SYNC Similar to I_LOCK, but limited in scope to writeback
  1156. * of inode dirty data. Having a separate lock for this
  1157. * purpose reduces latency and prevents some filesystem-
  1158. * specific deadlocks.
  1159. *
  1160. * Q: What is the difference between I_WILL_FREE and I_FREEING?
  1161. * Q: igrab() only checks on (I_FREEING|I_WILL_FREE). Should it also check on
  1162. * I_CLEAR? If not, why?
  1163. */
  1164. #define I_DIRTY_SYNC 1
  1165. #define I_DIRTY_DATASYNC 2
  1166. #define I_DIRTY_PAGES 4
  1167. #define I_NEW 8
  1168. #define I_WILL_FREE 16
  1169. #define I_FREEING 32
  1170. #define I_CLEAR 64
  1171. #define __I_LOCK 7
  1172. #define I_LOCK (1 << __I_LOCK)
  1173. #define __I_SYNC 8
  1174. #define I_SYNC (1 << __I_SYNC)
  1175. #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
  1176. extern void __mark_inode_dirty(struct inode *, int);
  1177. static inline void mark_inode_dirty(struct inode *inode)
  1178. {
  1179. __mark_inode_dirty(inode, I_DIRTY);
  1180. }
  1181. static inline void mark_inode_dirty_sync(struct inode *inode)
  1182. {
  1183. __mark_inode_dirty(inode, I_DIRTY_SYNC);
  1184. }
  1185. /**
  1186. * inc_nlink - directly increment an inode's link count
  1187. * @inode: inode
  1188. *
  1189. * This is a low-level filesystem helper to replace any
  1190. * direct filesystem manipulation of i_nlink. Currently,
  1191. * it is only here for parity with dec_nlink().
  1192. */
  1193. static inline void inc_nlink(struct inode *inode)
  1194. {
  1195. inode->i_nlink++;
  1196. }
  1197. static inline void inode_inc_link_count(struct inode *inode)
  1198. {
  1199. inc_nlink(inode);
  1200. mark_inode_dirty(inode);
  1201. }
  1202. /**
  1203. * drop_nlink - directly drop an inode's link count
  1204. * @inode: inode
  1205. *
  1206. * This is a low-level filesystem helper to replace any
  1207. * direct filesystem manipulation of i_nlink. In cases
  1208. * where we are attempting to track writes to the
  1209. * filesystem, a decrement to zero means an imminent
  1210. * write when the file is truncated and actually unlinked
  1211. * on the filesystem.
  1212. */
  1213. static inline void drop_nlink(struct inode *inode)
  1214. {
  1215. inode->i_nlink--;
  1216. }
  1217. /**
  1218. * clear_nlink - directly zero an inode's link count
  1219. * @inode: inode
  1220. *
  1221. * This is a low-level filesystem helper to replace any
  1222. * direct filesystem manipulation of i_nlink. See
  1223. * drop_nlink() for why we care about i_nlink hitting zero.
  1224. */
  1225. static inline void clear_nlink(struct inode *inode)
  1226. {
  1227. inode->i_nlink = 0;
  1228. }
  1229. static inline void inode_dec_link_count(struct inode *inode)
  1230. {
  1231. drop_nlink(inode);
  1232. mark_inode_dirty(inode);
  1233. }
  1234. /**
  1235. * inode_inc_iversion - increments i_version
  1236. * @inode: inode that need to be updated
  1237. *
  1238. * Every time the inode is modified, the i_version field will be incremented.
  1239. * The filesystem has to be mounted with i_version flag
  1240. */
  1241. static inline void inode_inc_iversion(struct inode *inode)
  1242. {
  1243. spin_lock(&inode->i_lock);
  1244. inode->i_version++;
  1245. spin_unlock(&inode->i_lock);
  1246. }
  1247. extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry);
  1248. static inline void file_accessed(struct file *file)
  1249. {
  1250. if (!(file->f_flags & O_NOATIME))
  1251. touch_atime(file->f_path.mnt, file->f_path.dentry);
  1252. }
  1253. int sync_inode(struct inode *inode, struct writeback_control *wbc);
  1254. struct file_system_type {
  1255. const char *name;
  1256. int fs_flags;
  1257. int (*get_sb) (struct file_system_type *, int,
  1258. const char *, void *, struct vfsmount *);
  1259. void (*kill_sb) (struct super_block *);
  1260. struct module *owner;
  1261. struct file_system_type * next;
  1262. struct list_head fs_supers;
  1263. struct lock_class_key s_lock_key;
  1264. struct lock_class_key s_umount_key;
  1265. struct lock_class_key i_lock_key;
  1266. struct lock_class_key i_mutex_key;
  1267. struct lock_class_key i_mutex_dir_key;
  1268. struct lock_class_key i_alloc_sem_key;
  1269. };
  1270. extern int get_sb_bdev(struct file_system_type *fs_type,
  1271. int flags, const char *dev_name, void *data,
  1272. int (*fill_super)(struct super_block *, void *, int),
  1273. struct vfsmount *mnt);
  1274. extern int get_sb_single(struct file_system_type *fs_type,
  1275. int flags, void *data,
  1276. int (*fill_super)(struct super_block *, void *, int),
  1277. struct vfsmount *mnt);
  1278. extern int get_sb_nodev(struct file_system_type *fs_type,
  1279. int flags, void *data,
  1280. int (*fill_super)(struct super_block *, void *, int),
  1281. struct vfsmount *mnt);
  1282. void generic_shutdown_super(struct super_block *sb);
  1283. void kill_block_super(struct super_block *sb);
  1284. void kill_anon_super(struct super_block *sb);
  1285. void kill_litter_super(struct super_block *sb);
  1286. void deactivate_super(struct super_block *sb);
  1287. int set_anon_super(struct super_block *s, void *data);
  1288. struct super_block *sget(struct file_system_type *type,
  1289. int (*test)(struct super_block *,void *),
  1290. int (*set)(struct super_block *,void *),
  1291. void *data);
  1292. extern int get_sb_pseudo(struct file_system_type *, char *,
  1293. const struct super_operations *ops, unsigned long,
  1294. struct vfsmount *mnt);
  1295. extern int simple_set_mnt(struct vfsmount *mnt, struct super_block *sb);
  1296. int __put_super(struct super_block *sb);
  1297. int __put_super_and_need_restart(struct super_block *sb);
  1298. void unnamed_dev_init(void);
  1299. /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
  1300. #define fops_get(fops) \
  1301. (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
  1302. #define fops_put(fops) \
  1303. do { if (fops) module_put((fops)->owner); } while(0)
  1304. extern int register_filesystem(struct file_system_type *);
  1305. extern int unregister_filesystem(struct file_system_type *);
  1306. extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
  1307. #define kern_mount(type) kern_mount_data(type, NULL)
  1308. extern int may_umount_tree(struct vfsmount *);
  1309. extern int may_umount(struct vfsmount *);
  1310. extern void umount_tree(struct vfsmount *, int, struct list_head *);
  1311. extern void release_mounts(struct list_head *);
  1312. extern long do_mount(char *, char *, char *, unsigned long, void *);
  1313. extern struct vfsmount *copy_tree(struct vfsmount *, struct dentry *, int);
  1314. extern void mnt_set_mountpoint(struct vfsmount *, struct dentry *,
  1315. struct vfsmount *);
  1316. extern struct vfsmount *collect_mounts(struct vfsmount *, struct dentry *);
  1317. extern void drop_collected_mounts(struct vfsmount *);
  1318. extern int vfs_statfs(struct dentry *, struct kstatfs *);
  1319. /* /sys/fs */
  1320. extern struct kobject *fs_kobj;
  1321. #define FLOCK_VERIFY_READ 1
  1322. #define FLOCK_VERIFY_WRITE 2
  1323. extern int locks_mandatory_locked(struct inode *);
  1324. extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
  1325. /*
  1326. * Candidates for mandatory locking have the setgid bit set
  1327. * but no group execute bit - an otherwise meaningless combination.
  1328. */
  1329. static inline int __mandatory_lock(struct inode *ino)
  1330. {
  1331. return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
  1332. }
  1333. /*
  1334. * ... and these candidates should be on MS_MANDLOCK mounted fs,
  1335. * otherwise these will be advisory locks
  1336. */
  1337. static inline int mandatory_lock(struct inode *ino)
  1338. {
  1339. return IS_MANDLOCK(ino) && __mandatory_lock(ino);
  1340. }
  1341. static inline int locks_verify_locked(struct inode *inode)
  1342. {
  1343. if (mandatory_lock(inode))
  1344. return locks_mandatory_locked(inode);
  1345. return 0;
  1346. }
  1347. extern int rw_verify_area(int, struct file *, loff_t *, size_t);
  1348. static inline int locks_verify_truncate(struct inode *inode,
  1349. struct file *filp,
  1350. loff_t size)
  1351. {
  1352. if (inode->i_flock && mandatory_lock(inode))
  1353. return locks_mandatory_area(
  1354. FLOCK_VERIFY_WRITE, inode, filp,
  1355. size < inode->i_size ? size : inode->i_size,
  1356. (size < inode->i_size ? inode->i_size - size
  1357. : size - inode->i_size)
  1358. );
  1359. return 0;
  1360. }
  1361. static inline int break_lease(struct inode *inode, unsigned int mode)
  1362. {
  1363. if (inode->i_flock)
  1364. return __break_lease(inode, mode);
  1365. return 0;
  1366. }
  1367. /* fs/open.c */
  1368. extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
  1369. struct file *filp);
  1370. extern long do_sys_open(int dfd, const char __user *filename, int flags,
  1371. int mode);
  1372. extern struct file *filp_open(const char *, int, int);
  1373. extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
  1374. extern int filp_close(struct file *, fl_owner_t id);
  1375. extern char * getname(const char __user *);
  1376. /* fs/dcache.c */
  1377. extern void __init vfs_caches_init_early(void);
  1378. extern void __init vfs_caches_init(unsigned long);
  1379. extern struct kmem_cache *names_cachep;
  1380. #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
  1381. #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
  1382. #ifndef CONFIG_AUDITSYSCALL
  1383. #define putname(name) __putname(name)
  1384. #else
  1385. extern void putname(const char *name);
  1386. #endif
  1387. #ifdef CONFIG_BLOCK
  1388. extern int register_blkdev(unsigned int, const char *);
  1389. extern void unregister_blkdev(unsigned int, const char *);
  1390. extern struct block_device *bdget(dev_t);
  1391. extern void bd_set_size(struct block_device *, loff_t size);
  1392. extern void bd_forget(struct inode *inode);
  1393. extern void bdput(struct block_device *);
  1394. extern struct block_device *open_by_devnum(dev_t, unsigned);
  1395. extern const struct address_space_operations def_blk_aops;
  1396. #else
  1397. static inline void bd_forget(struct inode *inode) {}
  1398. #endif
  1399. extern const struct file_operations def_blk_fops;
  1400. extern const struct file_operations def_chr_fops;
  1401. extern const struct file_operations bad_sock_fops;
  1402. extern const struct file_operations def_fifo_fops;
  1403. #ifdef CONFIG_BLOCK
  1404. extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
  1405. extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long);
  1406. extern int blkdev_driver_ioctl(struct inode *inode, struct file *file,
  1407. struct gendisk *disk, unsigned cmd,
  1408. unsigned long arg);
  1409. extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
  1410. extern int blkdev_get(struct block_device *, mode_t, unsigned);
  1411. extern int blkdev_put(struct block_device *);
  1412. extern int bd_claim(struct block_device *, void *);
  1413. extern void bd_release(struct block_device *);
  1414. #ifdef CONFIG_SYSFS
  1415. extern int bd_claim_by_disk(struct block_device *, void *, struct gendisk *);
  1416. extern void bd_release_from_disk(struct block_device *, struct gendisk *);
  1417. #else
  1418. #define bd_claim_by_disk(bdev, holder, disk) bd_claim(bdev, holder)
  1419. #define bd_release_from_disk(bdev, disk) bd_release(bdev)
  1420. #endif
  1421. #endif
  1422. /* fs/char_dev.c */
  1423. #define CHRDEV_MAJOR_HASH_SIZE 255
  1424. extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
  1425. extern int register_chrdev_region(dev_t, unsigned, const char *);
  1426. extern int register_chrdev(unsigned int, const char *,
  1427. const struct file_operations *);
  1428. extern void unregister_chrdev(unsigned int, const char *);
  1429. extern void unregister_chrdev_region(dev_t, unsigned);
  1430. extern int chrdev_open(struct inode *, struct file *);
  1431. extern void chrdev_show(struct seq_file *,off_t);
  1432. /* fs/block_dev.c */
  1433. #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
  1434. #ifdef CONFIG_BLOCK
  1435. #define BLKDEV_MAJOR_HASH_SIZE 255
  1436. extern const char *__bdevname(dev_t, char *buffer);
  1437. extern const char *bdevname(struct block_device *bdev, char *buffer);
  1438. extern struct block_device *lookup_bdev(const char *);
  1439. extern struct block_device *open_bdev_excl(const char *, int, void *);
  1440. extern void close_bdev_excl(struct block_device *);
  1441. extern void blkdev_show(struct seq_file *,off_t);
  1442. #else
  1443. #define BLKDEV_MAJOR_HASH_SIZE 0
  1444. #endif
  1445. extern void init_special_inode(struct inode *, umode_t, dev_t);
  1446. /* Invalid inode operations -- fs/bad_inode.c */
  1447. extern void make_bad_inode(struct inode *);
  1448. extern int is_bad_inode(struct inode *);
  1449. extern const struct file_operations read_fifo_fops;
  1450. extern const struct file_operations write_fifo_fops;
  1451. extern const struct file_operations rdwr_fifo_fops;
  1452. extern int fs_may_remount_ro(struct super_block *);
  1453. #ifdef CONFIG_BLOCK
  1454. /*
  1455. * return READ, READA, or WRITE
  1456. */
  1457. #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
  1458. /*
  1459. * return data direction, READ or WRITE
  1460. */
  1461. #define bio_data_dir(bio) ((bio)->bi_rw & 1)
  1462. extern int check_disk_change(struct block_device *);
  1463. extern int __invalidate_device(struct block_device *);
  1464. extern int invalidate_partition(struct gendisk *, int);
  1465. #endif
  1466. extern int invalidate_inodes(struct super_block *);
  1467. unsigned long __invalidate_mapping_pages(struct address_space *mapping,
  1468. pgoff_t start, pgoff_t end,
  1469. bool be_atomic);
  1470. unsigned long invalidate_mapping_pages(struct address_space *mapping,
  1471. pgoff_t start, pgoff_t end);
  1472. static inline unsigned long __deprecated
  1473. invalidate_inode_pages(struct address_space *mapping)
  1474. {
  1475. return invalidate_mapping_pages(mapping, 0, ~0UL);
  1476. }
  1477. static inline void invalidate_remote_inode(struct inode *inode)
  1478. {
  1479. if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
  1480. S_ISLNK(inode->i_mode))
  1481. invalidate_mapping_pages(inode->i_mapping, 0, -1);
  1482. }
  1483. extern int invalidate_inode_pages2(struct address_space *mapping);
  1484. extern int invalidate_inode_pages2_range(struct address_space *mapping,
  1485. pgoff_t start, pgoff_t end);
  1486. extern int write_inode_now(struct inode *, int);
  1487. extern int filemap_fdatawrite(struct address_space *);
  1488. extern int filemap_flush(struct address_space *);
  1489. extern int filemap_fdatawait(struct address_space *);
  1490. extern int filemap_write_and_wait(struct address_space *mapping);
  1491. extern int filemap_write_and_wait_range(struct address_space *mapping,
  1492. loff_t lstart, loff_t lend);
  1493. extern int wait_on_page_writeback_range(struct address_space *mapping,
  1494. pgoff_t start, pgoff_t end);
  1495. extern int __filemap_fdatawrite_range(struct address_space *mapping,
  1496. loff_t start, loff_t end, int sync_mode);
  1497. extern long do_fsync(struct file *file, int datasync);
  1498. extern void sync_supers(void);
  1499. extern void sync_filesystems(int wait);
  1500. extern void __fsync_super(struct super_block *sb);
  1501. extern void emergency_sync(void);
  1502. extern void emergency_remount(void);
  1503. extern int do_remount_sb(struct super_block *sb, int flags,
  1504. void *data, int force);
  1505. #ifdef CONFIG_BLOCK
  1506. extern sector_t bmap(struct inode *, sector_t);
  1507. #endif
  1508. extern int notify_change(struct dentry *, struct iattr *);
  1509. extern int permission(struct inode *, int, struct nameidata *);
  1510. extern int generic_permission(struct inode *, int,
  1511. int (*check_acl)(struct inode *, int));
  1512. extern int get_write_access(struct inode *);
  1513. extern int deny_write_access(struct file *);
  1514. static inline void put_write_access(struct inode * inode)
  1515. {
  1516. atomic_dec(&inode->i_writecount);
  1517. }
  1518. static inline void allow_write_access(struct file *file)
  1519. {
  1520. if (file)
  1521. atomic_inc(&file->f_path.dentry->d_inode->i_writecount);
  1522. }
  1523. extern int do_pipe(int *);
  1524. extern struct file *create_read_pipe(struct file *f);
  1525. extern struct file *create_write_pipe(void);
  1526. extern void free_write_pipe(struct file *);
  1527. extern int open_namei(int dfd, const char *, int, int, struct nameidata *);
  1528. extern int may_open(struct nameidata *, int, int);
  1529. extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
  1530. extern struct file * open_exec(const char *);
  1531. /* fs/dcache.c -- generic fs support functions */
  1532. extern int is_subdir(struct dentry *, struct dentry *);
  1533. extern ino_t find_inode_number(struct dentry *, struct qstr *);
  1534. #include <linux/err.h>
  1535. /* needed for stackable file system support */
  1536. extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
  1537. extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
  1538. extern void inode_init_once(struct inode *);
  1539. extern void iput(struct inode *);
  1540. extern struct inode * igrab(struct inode *);
  1541. extern ino_t iunique(struct super_block *, ino_t);
  1542. extern int inode_needs_sync(struct inode *inode);
  1543. extern void generic_delete_inode(struct inode *inode);
  1544. extern void generic_drop_inode(struct inode *inode);
  1545. extern struct inode *ilookup5_nowait(struct super_block *sb,
  1546. unsigned long hashval, int (*test)(struct inode *, void *),
  1547. void *data);
  1548. extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
  1549. int (*test)(struct inode *, void *), void *data);
  1550. extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
  1551. extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
  1552. extern struct inode * iget_locked(struct super_block *, unsigned long);
  1553. extern void unlock_new_inode(struct inode *);
  1554. static inline struct inode *iget(struct super_block *sb, unsigned long ino)
  1555. {
  1556. struct inode *inode = iget_locked(sb, ino);
  1557. if (inode && (inode->i_state & I_NEW)) {
  1558. sb->s_op->read_inode(inode);
  1559. unlock_new_inode(inode);
  1560. }
  1561. return inode;
  1562. }
  1563. extern void __iget(struct inode * inode);
  1564. extern void clear_inode(struct inode *);
  1565. extern void destroy_inode(struct inode *);
  1566. extern struct inode *new_inode(struct super_block *);
  1567. extern int __remove_suid(struct dentry *, int);
  1568. extern int should_remove_suid(struct dentry *);
  1569. extern int remove_suid(struct dentry *);
  1570. extern void __insert_inode_hash(struct inode *, unsigned long hashval);
  1571. extern void remove_inode_hash(struct inode *);
  1572. static inline void insert_inode_hash(struct inode *inode) {
  1573. __insert_inode_hash(inode, inode->i_ino);
  1574. }
  1575. extern struct file * get_empty_filp(void);
  1576. extern void file_move(struct file *f, struct list_head *list);
  1577. extern void file_kill(struct file *f);
  1578. #ifdef CONFIG_BLOCK
  1579. struct bio;
  1580. extern void submit_bio(int, struct bio *);
  1581. extern int bdev_read_only(struct block_device *);
  1582. #endif
  1583. extern int set_blocksize(struct block_device *, int);
  1584. extern int sb_set_blocksize(struct super_block *, int);
  1585. extern int sb_min_blocksize(struct super_block *, int);
  1586. extern int sb_has_dirty_inodes(struct super_block *);
  1587. extern int generic_file_mmap(struct file *, struct vm_area_struct *);
  1588. extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
  1589. extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
  1590. int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
  1591. extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
  1592. extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
  1593. extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
  1594. unsigned long, loff_t);
  1595. extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
  1596. unsigned long *, loff_t, loff_t *, size_t, size_t);
  1597. extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
  1598. unsigned long, loff_t, loff_t *, size_t, ssize_t);
  1599. extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
  1600. extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
  1601. extern void do_generic_mapping_read(struct address_space *mapping,
  1602. struct file_ra_state *, struct file *,
  1603. loff_t *, read_descriptor_t *, read_actor_t);
  1604. extern int generic_segment_checks(const struct iovec *iov,
  1605. unsigned long *nr_segs, size_t *count, int access_flags);
  1606. /* fs/splice.c */
  1607. extern ssize_t generic_file_splice_read(struct file *, loff_t *,
  1608. struct pipe_inode_info *, size_t, unsigned int);
  1609. extern ssize_t generic_file_splice_write(struct pipe_inode_info *,
  1610. struct file *, loff_t *, size_t, unsigned int);
  1611. extern ssize_t generic_file_splice_write_nolock(struct pipe_inode_info *,
  1612. struct file *, loff_t *, size_t, unsigned int);
  1613. extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
  1614. struct file *out, loff_t *, size_t len, unsigned int flags);
  1615. extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
  1616. size_t len, unsigned int flags);
  1617. extern void
  1618. file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
  1619. extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
  1620. extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
  1621. extern loff_t remote_llseek(struct file *file, loff_t offset, int origin);
  1622. extern int generic_file_open(struct inode * inode, struct file * filp);
  1623. extern int nonseekable_open(struct inode * inode, struct file * filp);
  1624. #ifdef CONFIG_FS_XIP
  1625. extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
  1626. loff_t *ppos);
  1627. extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
  1628. extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
  1629. size_t len, loff_t *ppos);
  1630. extern int xip_truncate_page(struct address_space *mapping, loff_t from);
  1631. #else
  1632. static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
  1633. {
  1634. return 0;
  1635. }
  1636. #endif
  1637. static inline void do_generic_file_read(struct file * filp, loff_t *ppos,
  1638. read_descriptor_t * desc,
  1639. read_actor_t actor)
  1640. {
  1641. do_generic_mapping_read(filp->f_mapping,
  1642. &filp->f_ra,
  1643. filp,
  1644. ppos,
  1645. desc,
  1646. actor);
  1647. }
  1648. #ifdef CONFIG_BLOCK
  1649. ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
  1650. struct block_device *bdev, const struct iovec *iov, loff_t offset,
  1651. unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io,
  1652. int lock_type);
  1653. enum {
  1654. DIO_LOCKING = 1, /* need locking between buffered and direct access */
  1655. DIO_NO_LOCKING, /* bdev; no locking at all between buffered/direct */
  1656. DIO_OWN_LOCKING, /* filesystem locks buffered and direct internally */
  1657. };
  1658. static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
  1659. struct inode *inode, struct block_device *bdev, const struct iovec *iov,
  1660. loff_t offset, unsigned long nr_segs, get_block_t get_block,
  1661. dio_iodone_t end_io)
  1662. {
  1663. return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
  1664. nr_segs, get_block, end_io, DIO_LOCKING);
  1665. }
  1666. static inline ssize_t blockdev_direct_IO_no_locking(int rw, struct kiocb *iocb,
  1667. struct inode *inode, struct block_device *bdev, const struct iovec *iov,
  1668. loff_t offset, unsigned long nr_segs, get_block_t get_block,
  1669. dio_iodone_t end_io)
  1670. {
  1671. return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
  1672. nr_segs, get_block, end_io, DIO_NO_LOCKING);
  1673. }
  1674. static inline ssize_t blockdev_direct_IO_own_locking(int rw, struct kiocb *iocb,
  1675. struct inode *inode, struct block_device *bdev, const struct iovec *iov,
  1676. loff_t offset, unsigned long nr_segs, get_block_t get_block,
  1677. dio_iodone_t end_io)
  1678. {
  1679. return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
  1680. nr_segs, get_block, end_io, DIO_OWN_LOCKING);
  1681. }
  1682. #endif
  1683. extern const struct file_operations generic_ro_fops;
  1684. #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
  1685. extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
  1686. extern int vfs_follow_link(struct nameidata *, const char *);
  1687. extern int page_readlink(struct dentry *, char __user *, int);
  1688. extern void *page_follow_link_light(struct dentry *, struct nameidata *);
  1689. extern void page_put_link(struct dentry *, struct nameidata *, void *);
  1690. extern int __page_symlink(struct inode *inode, const char *symname, int len,
  1691. gfp_t gfp_mask);
  1692. extern int page_symlink(struct inode *inode, const char *symname, int len);
  1693. extern const struct inode_operations page_symlink_inode_operations;
  1694. extern int generic_readlink(struct dentry *, char __user *, int);
  1695. extern void generic_fillattr(struct inode *, struct kstat *);
  1696. extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
  1697. void inode_add_bytes(struct inode *inode, loff_t bytes);
  1698. void inode_sub_bytes(struct inode *inode, loff_t bytes);
  1699. loff_t inode_get_bytes(struct inode *inode);
  1700. void inode_set_bytes(struct inode *inode, loff_t bytes);
  1701. extern int vfs_readdir(struct file *, filldir_t, void *);
  1702. extern int vfs_stat(char __user *, struct kstat *);
  1703. extern int vfs_lstat(char __user *, struct kstat *);
  1704. extern int vfs_stat_fd(int dfd, char __user *, struct kstat *);
  1705. extern int vfs_lstat_fd(int dfd, char __user *, struct kstat *);
  1706. extern int vfs_fstat(unsigned int, struct kstat *);
  1707. extern long vfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
  1708. extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
  1709. unsigned long arg);
  1710. extern void get_filesystem(struct file_system_type *fs);
  1711. extern void put_filesystem(struct file_system_type *fs);
  1712. extern struct file_system_type *get_fs_type(const char *name);
  1713. extern struct super_block *get_super(struct block_device *);
  1714. extern struct super_block *user_get_super(dev_t);
  1715. extern void drop_super(struct super_block *sb);
  1716. extern int dcache_dir_open(struct inode *, struct file *);
  1717. extern int dcache_dir_close(struct inode *, struct file *);
  1718. extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
  1719. extern int dcache_readdir(struct file *, void *, filldir_t);
  1720. extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
  1721. extern int simple_statfs(struct dentry *, struct kstatfs *);
  1722. extern int simple_link(struct dentry *, struct inode *, struct dentry *);
  1723. extern int simple_unlink(struct inode *, struct dentry *);
  1724. extern int simple_rmdir(struct inode *, struct dentry *);
  1725. extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
  1726. extern int simple_sync_file(struct file *, struct dentry *, int);
  1727. extern int simple_empty(struct dentry *);
  1728. extern int simple_readpage(struct file *file, struct page *page);
  1729. extern int simple_prepare_write(struct file *file, struct page *page,
  1730. unsigned offset, unsigned to);
  1731. extern int simple_write_begin(struct file *file, struct address_space *mapping,
  1732. loff_t pos, unsigned len, unsigned flags,
  1733. struct page **pagep, void **fsdata);
  1734. extern int simple_write_end(struct file *file, struct address_space *mapping,
  1735. loff_t pos, unsigned len, unsigned copied,
  1736. struct page *page, void *fsdata);
  1737. extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
  1738. extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
  1739. extern const struct file_operations simple_dir_operations;
  1740. extern const struct inode_operations simple_dir_inode_operations;
  1741. struct tree_descr { char *name; const struct file_operations *ops; int mode; };
  1742. struct dentry *d_alloc_name(struct dentry *, const char *);
  1743. extern int simple_fill_super(struct super_block *, int, struct tree_descr *);
  1744. extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
  1745. extern void simple_release_fs(struct vfsmount **mount, int *count);
  1746. extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t);
  1747. #ifdef CONFIG_MIGRATION
  1748. extern int buffer_migrate_page(struct address_space *,
  1749. struct page *, struct page *);
  1750. #else
  1751. #define buffer_migrate_page NULL
  1752. #endif
  1753. extern int inode_change_ok(struct inode *, struct iattr *);
  1754. extern int __must_check inode_setattr(struct inode *, struct iattr *);
  1755. extern void file_update_time(struct file *file);
  1756. static inline ino_t parent_ino(struct dentry *dentry)
  1757. {
  1758. ino_t res;
  1759. spin_lock(&dentry->d_lock);
  1760. res = dentry->d_parent->d_inode->i_ino;
  1761. spin_unlock(&dentry->d_lock);
  1762. return res;
  1763. }
  1764. /* kernel/fork.c */
  1765. extern int unshare_files(void);
  1766. /* Transaction based IO helpers */
  1767. /*
  1768. * An argresp is stored in an allocated page and holds the
  1769. * size of the argument or response, along with its content
  1770. */
  1771. struct simple_transaction_argresp {
  1772. ssize_t size;
  1773. char data[0];
  1774. };
  1775. #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
  1776. char *simple_transaction_get(struct file *file, const char __user *buf,
  1777. size_t size);
  1778. ssize_t simple_transaction_read(struct file *file, char __user *buf,
  1779. size_t size, loff_t *pos);
  1780. int simple_transaction_release(struct inode *inode, struct file *file);
  1781. static inline void simple_transaction_set(struct file *file, size_t n)
  1782. {
  1783. struct simple_transaction_argresp *ar = file->private_data;
  1784. BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
  1785. /*
  1786. * The barrier ensures that ar->size will really remain zero until
  1787. * ar->data is ready for reading.
  1788. */
  1789. smp_mb();
  1790. ar->size = n;
  1791. }
  1792. /*
  1793. * simple attribute files
  1794. *
  1795. * These attributes behave similar to those in sysfs:
  1796. *
  1797. * Writing to an attribute immediately sets a value, an open file can be
  1798. * written to multiple times.
  1799. *
  1800. * Reading from an attribute creates a buffer from the value that might get
  1801. * read with multiple read calls. When the attribute has been read
  1802. * completely, no further read calls are possible until the file is opened
  1803. * again.
  1804. *
  1805. * All attributes contain a text representation of a numeric value
  1806. * that are accessed with the get() and set() functions.
  1807. */
  1808. #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
  1809. static int __fops ## _open(struct inode *inode, struct file *file) \
  1810. { \
  1811. __simple_attr_check_format(__fmt, 0ull); \
  1812. return simple_attr_open(inode, file, __get, __set, __fmt); \
  1813. } \
  1814. static struct file_operations __fops = { \
  1815. .owner = THIS_MODULE, \
  1816. .open = __fops ## _open, \
  1817. .release = simple_attr_close, \
  1818. .read = simple_attr_read, \
  1819. .write = simple_attr_write, \
  1820. };
  1821. static inline void __attribute__((format(printf, 1, 2)))
  1822. __simple_attr_check_format(const char *fmt, ...)
  1823. {
  1824. /* don't do anything, just let the compiler check the arguments; */
  1825. }
  1826. int simple_attr_open(struct inode *inode, struct file *file,
  1827. u64 (*get)(void *), void (*set)(void *, u64),
  1828. const char *fmt);
  1829. int simple_attr_close(struct inode *inode, struct file *file);
  1830. ssize_t simple_attr_read(struct file *file, char __user *buf,
  1831. size_t len, loff_t *ppos);
  1832. ssize_t simple_attr_write(struct file *file, const char __user *buf,
  1833. size_t len, loff_t *ppos);
  1834. #ifdef CONFIG_SECURITY
  1835. static inline char *alloc_secdata(void)
  1836. {
  1837. return (char *)get_zeroed_page(GFP_KERNEL);
  1838. }
  1839. static inline void free_secdata(void *secdata)
  1840. {
  1841. free_page((unsigned long)secdata);
  1842. }
  1843. #else
  1844. static inline char *alloc_secdata(void)
  1845. {
  1846. return (char *)1;
  1847. }
  1848. static inline void free_secdata(void *secdata)
  1849. { }
  1850. #endif /* CONFIG_SECURITY */
  1851. struct ctl_table;
  1852. int proc_nr_files(struct ctl_table *table, int write, struct file *filp,
  1853. void __user *buffer, size_t *lenp, loff_t *ppos);
  1854. int get_filesystem_list(char * buf);
  1855. #endif /* __KERNEL__ */
  1856. #endif /* _LINUX_FS_H */