fs.h 67 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050105110521053105410551056105710581059106010611062106310641065106610671068106910701071107210731074107510761077107810791080108110821083108410851086108710881089109010911092109310941095109610971098109911001101110211031104110511061107110811091110111111121113111411151116111711181119112011211122112311241125112611271128112911301131113211331134113511361137113811391140114111421143114411451146114711481149115011511152115311541155115611571158115911601161116211631164116511661167116811691170117111721173117411751176117711781179118011811182118311841185118611871188118911901191119211931194119511961197119811991200120112021203120412051206120712081209121012111212121312141215121612171218121912201221122212231224122512261227122812291230123112321233123412351236123712381239124012411242124312441245124612471248124912501251125212531254125512561257125812591260126112621263126412651266126712681269127012711272127312741275127612771278127912801281128212831284128512861287128812891290129112921293129412951296129712981299130013011302130313041305130613071308130913101311131213131314131513161317131813191320132113221323132413251326132713281329133013311332133313341335133613371338133913401341134213431344134513461347134813491350135113521353135413551356135713581359136013611362136313641365136613671368136913701371137213731374137513761377137813791380138113821383138413851386138713881389139013911392139313941395139613971398139914001401140214031404140514061407140814091410141114121413141414151416141714181419142014211422142314241425142614271428142914301431143214331434143514361437143814391440144114421443144414451446144714481449145014511452145314541455145614571458145914601461146214631464146514661467146814691470147114721473147414751476147714781479148014811482148314841485148614871488148914901491149214931494149514961497149814991500150115021503150415051506150715081509151015111512151315141515151615171518151915201521152215231524152515261527152815291530153115321533153415351536153715381539154015411542154315441545154615471548154915501551155215531554155515561557155815591560156115621563156415651566156715681569157015711572157315741575157615771578157915801581158215831584158515861587158815891590159115921593159415951596159715981599160016011602160316041605160616071608160916101611161216131614161516161617161816191620162116221623162416251626162716281629163016311632163316341635163616371638163916401641164216431644164516461647164816491650165116521653165416551656165716581659166016611662166316641665166616671668166916701671167216731674167516761677167816791680168116821683168416851686168716881689169016911692169316941695169616971698169917001701170217031704170517061707170817091710171117121713171417151716171717181719172017211722172317241725172617271728172917301731173217331734173517361737173817391740174117421743174417451746174717481749175017511752175317541755175617571758175917601761176217631764176517661767176817691770177117721773177417751776177717781779178017811782178317841785178617871788178917901791179217931794179517961797179817991800180118021803180418051806180718081809181018111812181318141815181618171818181918201821182218231824182518261827182818291830183118321833183418351836183718381839184018411842184318441845184618471848184918501851185218531854185518561857185818591860186118621863186418651866186718681869187018711872
  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/config.h>
  8. #include <linux/limits.h>
  9. #include <linux/ioctl.h>
  10. /*
  11. * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
  12. * the file limit at runtime and only root can increase the per-process
  13. * nr_file rlimit, so it's safe to set up a ridiculously high absolute
  14. * upper limit on files-per-process.
  15. *
  16. * Some programs (notably those using select()) may have to be
  17. * recompiled to take full advantage of the new limits..
  18. */
  19. /* Fixed constants first: */
  20. #undef NR_OPEN
  21. #define NR_OPEN (1024*1024) /* Absolute upper limit on fd num */
  22. #define INR_OPEN 1024 /* Initial setting for nfile rlimits */
  23. #define BLOCK_SIZE_BITS 10
  24. #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
  25. /* And dynamically-tunable limits and defaults: */
  26. struct files_stat_struct {
  27. int nr_files; /* read only */
  28. int nr_free_files; /* read only */
  29. int max_files; /* tunable */
  30. };
  31. extern struct files_stat_struct files_stat;
  32. extern int get_max_files(void);
  33. struct inodes_stat_t {
  34. int nr_inodes;
  35. int nr_unused;
  36. int dummy[5];
  37. };
  38. extern struct inodes_stat_t inodes_stat;
  39. extern int leases_enable, lease_break_time;
  40. #ifdef CONFIG_DNOTIFY
  41. extern int dir_notify_enable;
  42. #endif
  43. #define NR_FILE 8192 /* this can well be larger on a larger system */
  44. #define MAY_EXEC 1
  45. #define MAY_WRITE 2
  46. #define MAY_READ 4
  47. #define MAY_APPEND 8
  48. #define FMODE_READ 1
  49. #define FMODE_WRITE 2
  50. /* Internal kernel extensions */
  51. #define FMODE_LSEEK 4
  52. #define FMODE_PREAD 8
  53. #define FMODE_PWRITE FMODE_PREAD /* These go hand in hand */
  54. #define RW_MASK 1
  55. #define RWA_MASK 2
  56. #define READ 0
  57. #define WRITE 1
  58. #define READA 2 /* read-ahead - don't block if no resources */
  59. #define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */
  60. #define SPECIAL 4 /* For non-blockdevice requests in request queue */
  61. #define READ_SYNC (READ | (1 << BIO_RW_SYNC))
  62. #define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC))
  63. #define WRITE_BARRIER ((1 << BIO_RW) | (1 << BIO_RW_BARRIER))
  64. #define SEL_IN 1
  65. #define SEL_OUT 2
  66. #define SEL_EX 4
  67. /* public flags for file_system_type */
  68. #define FS_REQUIRES_DEV 1
  69. #define FS_BINARY_MOUNTDATA 2
  70. #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
  71. #define FS_ODD_RENAME 32768 /* Temporary stuff; will go away as soon
  72. * as nfs_rename() will be cleaned up
  73. */
  74. /*
  75. * These are the fs-independent mount-flags: up to 32 flags are supported
  76. */
  77. #define MS_RDONLY 1 /* Mount read-only */
  78. #define MS_NOSUID 2 /* Ignore suid and sgid bits */
  79. #define MS_NODEV 4 /* Disallow access to device special files */
  80. #define MS_NOEXEC 8 /* Disallow program execution */
  81. #define MS_SYNCHRONOUS 16 /* Writes are synced at once */
  82. #define MS_REMOUNT 32 /* Alter flags of a mounted FS */
  83. #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
  84. #define MS_DIRSYNC 128 /* Directory modifications are synchronous */
  85. #define MS_NOATIME 1024 /* Do not update access times. */
  86. #define MS_NODIRATIME 2048 /* Do not update directory access times */
  87. #define MS_BIND 4096
  88. #define MS_MOVE 8192
  89. #define MS_REC 16384
  90. #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence.
  91. MS_VERBOSE is deprecated. */
  92. #define MS_SILENT 32768
  93. #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
  94. #define MS_UNBINDABLE (1<<17) /* change to unbindable */
  95. #define MS_PRIVATE (1<<18) /* change to private */
  96. #define MS_SLAVE (1<<19) /* change to slave */
  97. #define MS_SHARED (1<<20) /* change to shared */
  98. #define MS_ACTIVE (1<<30)
  99. #define MS_NOUSER (1<<31)
  100. /*
  101. * Superblock flags that can be altered by MS_REMOUNT
  102. */
  103. #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK)
  104. /*
  105. * Old magic mount flag and mask
  106. */
  107. #define MS_MGC_VAL 0xC0ED0000
  108. #define MS_MGC_MSK 0xffff0000
  109. /* Inode flags - they have nothing to superblock flags now */
  110. #define S_SYNC 1 /* Writes are synced at once */
  111. #define S_NOATIME 2 /* Do not update access times */
  112. #define S_APPEND 4 /* Append-only file */
  113. #define S_IMMUTABLE 8 /* Immutable file */
  114. #define S_DEAD 16 /* removed, but still open directory */
  115. #define S_NOQUOTA 32 /* Inode is not counted to quota */
  116. #define S_DIRSYNC 64 /* Directory modifications are synchronous */
  117. #define S_NOCMTIME 128 /* Do not update file c/mtime */
  118. #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
  119. #define S_PRIVATE 512 /* Inode is fs-internal */
  120. /*
  121. * Note that nosuid etc flags are inode-specific: setting some file-system
  122. * flags just means all the inodes inherit those flags by default. It might be
  123. * possible to override it selectively if you really wanted to with some
  124. * ioctl() that is not currently implemented.
  125. *
  126. * Exception: MS_RDONLY is always applied to the entire file system.
  127. *
  128. * Unfortunately, it is possible to change a filesystems flags with it mounted
  129. * with files in use. This means that all of the inodes will not have their
  130. * i_flags updated. Hence, i_flags no longer inherit the superblock mount
  131. * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
  132. */
  133. #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
  134. #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
  135. #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
  136. ((inode)->i_flags & S_SYNC))
  137. #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
  138. ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
  139. #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
  140. #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
  141. #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
  142. #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
  143. #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
  144. #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
  145. #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
  146. #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
  147. #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
  148. /* the read-only stuff doesn't really belong here, but any other place is
  149. probably as bad and I don't want to create yet another include file. */
  150. #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
  151. #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
  152. #define BLKRRPART _IO(0x12,95) /* re-read partition table */
  153. #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
  154. #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
  155. #define BLKRASET _IO(0x12,98) /* set read ahead for block device */
  156. #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
  157. #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
  158. #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
  159. #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
  160. #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
  161. #define BLKSSZGET _IO(0x12,104)/* get block device sector size */
  162. #if 0
  163. #define BLKPG _IO(0x12,105)/* See blkpg.h */
  164. /* Some people are morons. Do not use sizeof! */
  165. #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
  166. #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
  167. /* This was here just to show that the number is taken -
  168. probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
  169. #endif
  170. /* A jump here: 108-111 have been used for various private purposes. */
  171. #define BLKBSZGET _IOR(0x12,112,size_t)
  172. #define BLKBSZSET _IOW(0x12,113,size_t)
  173. #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
  174. #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
  175. #define BLKTRACESTART _IO(0x12,116)
  176. #define BLKTRACESTOP _IO(0x12,117)
  177. #define BLKTRACETEARDOWN _IO(0x12,118)
  178. #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
  179. #define FIBMAP _IO(0x00,1) /* bmap access */
  180. #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
  181. #ifdef __KERNEL__
  182. #include <linux/linkage.h>
  183. #include <linux/wait.h>
  184. #include <linux/types.h>
  185. #include <linux/kdev_t.h>
  186. #include <linux/dcache.h>
  187. #include <linux/stat.h>
  188. #include <linux/cache.h>
  189. #include <linux/kobject.h>
  190. #include <linux/list.h>
  191. #include <linux/radix-tree.h>
  192. #include <linux/prio_tree.h>
  193. #include <linux/init.h>
  194. #include <linux/sched.h>
  195. #include <linux/mutex.h>
  196. #include <asm/atomic.h>
  197. #include <asm/semaphore.h>
  198. #include <asm/byteorder.h>
  199. struct hd_geometry;
  200. struct iovec;
  201. struct nameidata;
  202. struct kiocb;
  203. struct pipe_inode_info;
  204. struct poll_table_struct;
  205. struct kstatfs;
  206. struct vm_area_struct;
  207. struct vfsmount;
  208. extern void __init inode_init(unsigned long);
  209. extern void __init inode_init_early(void);
  210. extern void __init mnt_init(unsigned long);
  211. extern void __init files_init(unsigned long);
  212. struct buffer_head;
  213. typedef int (get_block_t)(struct inode *inode, sector_t iblock,
  214. struct buffer_head *bh_result, int create);
  215. typedef int (get_blocks_t)(struct inode *inode, sector_t iblock,
  216. unsigned long max_blocks,
  217. struct buffer_head *bh_result, int create);
  218. typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
  219. ssize_t bytes, void *private);
  220. /*
  221. * Attribute flags. These should be or-ed together to figure out what
  222. * has been changed!
  223. */
  224. #define ATTR_MODE 1
  225. #define ATTR_UID 2
  226. #define ATTR_GID 4
  227. #define ATTR_SIZE 8
  228. #define ATTR_ATIME 16
  229. #define ATTR_MTIME 32
  230. #define ATTR_CTIME 64
  231. #define ATTR_ATIME_SET 128
  232. #define ATTR_MTIME_SET 256
  233. #define ATTR_FORCE 512 /* Not a change, but a change it */
  234. #define ATTR_ATTR_FLAG 1024
  235. #define ATTR_KILL_SUID 2048
  236. #define ATTR_KILL_SGID 4096
  237. #define ATTR_FILE 8192
  238. /*
  239. * This is the Inode Attributes structure, used for notify_change(). It
  240. * uses the above definitions as flags, to know which values have changed.
  241. * Also, in this manner, a Filesystem can look at only the values it cares
  242. * about. Basically, these are the attributes that the VFS layer can
  243. * request to change from the FS layer.
  244. *
  245. * Derek Atkins <warlord@MIT.EDU> 94-10-20
  246. */
  247. struct iattr {
  248. unsigned int ia_valid;
  249. umode_t ia_mode;
  250. uid_t ia_uid;
  251. gid_t ia_gid;
  252. loff_t ia_size;
  253. struct timespec ia_atime;
  254. struct timespec ia_mtime;
  255. struct timespec ia_ctime;
  256. /*
  257. * Not an attribute, but an auxilary info for filesystems wanting to
  258. * implement an ftruncate() like method. NOTE: filesystem should
  259. * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
  260. */
  261. struct file *ia_file;
  262. };
  263. /*
  264. * Includes for diskquotas.
  265. */
  266. #include <linux/quota.h>
  267. /**
  268. * enum positive_aop_returns - aop return codes with specific semantics
  269. *
  270. * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
  271. * completed, that the page is still locked, and
  272. * should be considered active. The VM uses this hint
  273. * to return the page to the active list -- it won't
  274. * be a candidate for writeback again in the near
  275. * future. Other callers must be careful to unlock
  276. * the page if they get this return. Returned by
  277. * writepage();
  278. *
  279. * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
  280. * unlocked it and the page might have been truncated.
  281. * The caller should back up to acquiring a new page and
  282. * trying again. The aop will be taking reasonable
  283. * precautions not to livelock. If the caller held a page
  284. * reference, it should drop it before retrying. Returned
  285. * by readpage(), prepare_write(), and commit_write().
  286. *
  287. * address_space_operation functions return these large constants to indicate
  288. * special semantics to the caller. These are much larger than the bytes in a
  289. * page to allow for functions that return the number of bytes operated on in a
  290. * given page.
  291. */
  292. enum positive_aop_returns {
  293. AOP_WRITEPAGE_ACTIVATE = 0x80000,
  294. AOP_TRUNCATED_PAGE = 0x80001,
  295. };
  296. /*
  297. * oh the beauties of C type declarations.
  298. */
  299. struct page;
  300. struct address_space;
  301. struct writeback_control;
  302. struct address_space_operations {
  303. int (*writepage)(struct page *page, struct writeback_control *wbc);
  304. int (*readpage)(struct file *, struct page *);
  305. int (*sync_page)(struct page *);
  306. /* Write back some dirty pages from this mapping. */
  307. int (*writepages)(struct address_space *, struct writeback_control *);
  308. /* Set a page dirty. Return true if this dirtied it */
  309. int (*set_page_dirty)(struct page *page);
  310. int (*readpages)(struct file *filp, struct address_space *mapping,
  311. struct list_head *pages, unsigned nr_pages);
  312. /*
  313. * ext3 requires that a successful prepare_write() call be followed
  314. * by a commit_write() call - they must be balanced
  315. */
  316. int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
  317. int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
  318. /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
  319. sector_t (*bmap)(struct address_space *, sector_t);
  320. int (*invalidatepage) (struct page *, unsigned long);
  321. int (*releasepage) (struct page *, gfp_t);
  322. ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
  323. loff_t offset, unsigned long nr_segs);
  324. struct page* (*get_xip_page)(struct address_space *, sector_t,
  325. int);
  326. /* migrate the contents of a page to the specified target */
  327. int (*migratepage) (struct page *, struct page *);
  328. };
  329. struct backing_dev_info;
  330. struct address_space {
  331. struct inode *host; /* owner: inode, block_device */
  332. struct radix_tree_root page_tree; /* radix tree of all pages */
  333. rwlock_t tree_lock; /* and rwlock protecting it */
  334. unsigned int i_mmap_writable;/* count VM_SHARED mappings */
  335. struct prio_tree_root i_mmap; /* tree of private and shared mappings */
  336. struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
  337. spinlock_t i_mmap_lock; /* protect tree, count, list */
  338. unsigned int truncate_count; /* Cover race condition with truncate */
  339. unsigned long nrpages; /* number of total pages */
  340. pgoff_t writeback_index;/* writeback starts here */
  341. struct address_space_operations *a_ops; /* methods */
  342. unsigned long flags; /* error bits/gfp mask */
  343. struct backing_dev_info *backing_dev_info; /* device readahead, etc */
  344. spinlock_t private_lock; /* for use by the address_space */
  345. struct list_head private_list; /* ditto */
  346. struct address_space *assoc_mapping; /* ditto */
  347. } __attribute__((aligned(sizeof(long))));
  348. /*
  349. * On most architectures that alignment is already the case; but
  350. * must be enforced here for CRIS, to let the least signficant bit
  351. * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
  352. */
  353. struct block_device {
  354. dev_t bd_dev; /* not a kdev_t - it's a search key */
  355. struct inode * bd_inode; /* will die */
  356. int bd_openers;
  357. struct mutex bd_mutex; /* open/close mutex */
  358. struct mutex bd_mount_mutex; /* mount mutex */
  359. struct list_head bd_inodes;
  360. void * bd_holder;
  361. int bd_holders;
  362. struct block_device * bd_contains;
  363. unsigned bd_block_size;
  364. struct hd_struct * bd_part;
  365. /* number of times partitions within this device have been opened. */
  366. unsigned bd_part_count;
  367. int bd_invalidated;
  368. struct gendisk * bd_disk;
  369. struct list_head bd_list;
  370. struct backing_dev_info *bd_inode_backing_dev_info;
  371. /*
  372. * Private data. You must have bd_claim'ed the block_device
  373. * to use this. NOTE: bd_claim allows an owner to claim
  374. * the same device multiple times, the owner must take special
  375. * care to not mess up bd_private for that case.
  376. */
  377. unsigned long bd_private;
  378. };
  379. /*
  380. * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
  381. * radix trees
  382. */
  383. #define PAGECACHE_TAG_DIRTY 0
  384. #define PAGECACHE_TAG_WRITEBACK 1
  385. int mapping_tagged(struct address_space *mapping, int tag);
  386. /*
  387. * Might pages of this file be mapped into userspace?
  388. */
  389. static inline int mapping_mapped(struct address_space *mapping)
  390. {
  391. return !prio_tree_empty(&mapping->i_mmap) ||
  392. !list_empty(&mapping->i_mmap_nonlinear);
  393. }
  394. /*
  395. * Might pages of this file have been modified in userspace?
  396. * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
  397. * marks vma as VM_SHARED if it is shared, and the file was opened for
  398. * writing i.e. vma may be mprotected writable even if now readonly.
  399. */
  400. static inline int mapping_writably_mapped(struct address_space *mapping)
  401. {
  402. return mapping->i_mmap_writable != 0;
  403. }
  404. /*
  405. * Use sequence counter to get consistent i_size on 32-bit processors.
  406. */
  407. #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  408. #include <linux/seqlock.h>
  409. #define __NEED_I_SIZE_ORDERED
  410. #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
  411. #else
  412. #define i_size_ordered_init(inode) do { } while (0)
  413. #endif
  414. struct inode {
  415. struct hlist_node i_hash;
  416. struct list_head i_list;
  417. struct list_head i_sb_list;
  418. struct list_head i_dentry;
  419. unsigned long i_ino;
  420. atomic_t i_count;
  421. umode_t i_mode;
  422. unsigned int i_nlink;
  423. uid_t i_uid;
  424. gid_t i_gid;
  425. dev_t i_rdev;
  426. loff_t i_size;
  427. struct timespec i_atime;
  428. struct timespec i_mtime;
  429. struct timespec i_ctime;
  430. unsigned int i_blkbits;
  431. unsigned long i_blksize;
  432. unsigned long i_version;
  433. unsigned long i_blocks;
  434. unsigned short i_bytes;
  435. spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
  436. struct mutex i_mutex;
  437. struct rw_semaphore i_alloc_sem;
  438. struct inode_operations *i_op;
  439. struct file_operations *i_fop; /* former ->i_op->default_file_ops */
  440. struct super_block *i_sb;
  441. struct file_lock *i_flock;
  442. struct address_space *i_mapping;
  443. struct address_space i_data;
  444. #ifdef CONFIG_QUOTA
  445. struct dquot *i_dquot[MAXQUOTAS];
  446. #endif
  447. /* These three should probably be a union */
  448. struct list_head i_devices;
  449. struct pipe_inode_info *i_pipe;
  450. struct block_device *i_bdev;
  451. struct cdev *i_cdev;
  452. int i_cindex;
  453. __u32 i_generation;
  454. #ifdef CONFIG_DNOTIFY
  455. unsigned long i_dnotify_mask; /* Directory notify events */
  456. struct dnotify_struct *i_dnotify; /* for directory notifications */
  457. #endif
  458. #ifdef CONFIG_INOTIFY
  459. struct list_head inotify_watches; /* watches on this inode */
  460. struct mutex inotify_mutex; /* protects the watches list */
  461. #endif
  462. unsigned long i_state;
  463. unsigned long dirtied_when; /* jiffies of first dirtying */
  464. unsigned int i_flags;
  465. atomic_t i_writecount;
  466. void *i_security;
  467. union {
  468. void *generic_ip;
  469. } u;
  470. #ifdef __NEED_I_SIZE_ORDERED
  471. seqcount_t i_size_seqcount;
  472. #endif
  473. };
  474. /*
  475. * NOTE: in a 32bit arch with a preemptable kernel and
  476. * an UP compile the i_size_read/write must be atomic
  477. * with respect to the local cpu (unlike with preempt disabled),
  478. * but they don't need to be atomic with respect to other cpus like in
  479. * true SMP (so they need either to either locally disable irq around
  480. * the read or for example on x86 they can be still implemented as a
  481. * cmpxchg8b without the need of the lock prefix). For SMP compiles
  482. * and 64bit archs it makes no difference if preempt is enabled or not.
  483. */
  484. static inline loff_t i_size_read(struct inode *inode)
  485. {
  486. #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  487. loff_t i_size;
  488. unsigned int seq;
  489. do {
  490. seq = read_seqcount_begin(&inode->i_size_seqcount);
  491. i_size = inode->i_size;
  492. } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
  493. return i_size;
  494. #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
  495. loff_t i_size;
  496. preempt_disable();
  497. i_size = inode->i_size;
  498. preempt_enable();
  499. return i_size;
  500. #else
  501. return inode->i_size;
  502. #endif
  503. }
  504. static inline void i_size_write(struct inode *inode, loff_t i_size)
  505. {
  506. #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
  507. write_seqcount_begin(&inode->i_size_seqcount);
  508. inode->i_size = i_size;
  509. write_seqcount_end(&inode->i_size_seqcount);
  510. #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
  511. preempt_disable();
  512. inode->i_size = i_size;
  513. preempt_enable();
  514. #else
  515. inode->i_size = i_size;
  516. #endif
  517. }
  518. static inline unsigned iminor(struct inode *inode)
  519. {
  520. return MINOR(inode->i_rdev);
  521. }
  522. static inline unsigned imajor(struct inode *inode)
  523. {
  524. return MAJOR(inode->i_rdev);
  525. }
  526. extern struct block_device *I_BDEV(struct inode *inode);
  527. struct fown_struct {
  528. rwlock_t lock; /* protects pid, uid, euid fields */
  529. int pid; /* pid or -pgrp where SIGIO should be sent */
  530. uid_t uid, euid; /* uid/euid of process setting the owner */
  531. void *security;
  532. int signum; /* posix.1b rt signal to be delivered on IO */
  533. };
  534. /*
  535. * Track a single file's readahead state
  536. */
  537. struct file_ra_state {
  538. unsigned long start; /* Current window */
  539. unsigned long size;
  540. unsigned long flags; /* ra flags RA_FLAG_xxx*/
  541. unsigned long cache_hit; /* cache hit count*/
  542. unsigned long prev_page; /* Cache last read() position */
  543. unsigned long ahead_start; /* Ahead window */
  544. unsigned long ahead_size;
  545. unsigned long ra_pages; /* Maximum readahead window */
  546. unsigned long mmap_hit; /* Cache hit stat for mmap accesses */
  547. unsigned long mmap_miss; /* Cache miss stat for mmap accesses */
  548. };
  549. #define RA_FLAG_MISS 0x01 /* a cache miss occured against this file */
  550. #define RA_FLAG_INCACHE 0x02 /* file is already in cache */
  551. struct file {
  552. /*
  553. * fu_list becomes invalid after file_free is called and queued via
  554. * fu_rcuhead for RCU freeing
  555. */
  556. union {
  557. struct list_head fu_list;
  558. struct rcu_head fu_rcuhead;
  559. } f_u;
  560. struct dentry *f_dentry;
  561. struct vfsmount *f_vfsmnt;
  562. struct file_operations *f_op;
  563. atomic_t f_count;
  564. unsigned int f_flags;
  565. mode_t f_mode;
  566. loff_t f_pos;
  567. struct fown_struct f_owner;
  568. unsigned int f_uid, f_gid;
  569. struct file_ra_state f_ra;
  570. unsigned long f_version;
  571. void *f_security;
  572. /* needed for tty driver, and maybe others */
  573. void *private_data;
  574. #ifdef CONFIG_EPOLL
  575. /* Used by fs/eventpoll.c to link all the hooks to this file */
  576. struct list_head f_ep_links;
  577. spinlock_t f_ep_lock;
  578. #endif /* #ifdef CONFIG_EPOLL */
  579. struct address_space *f_mapping;
  580. };
  581. extern spinlock_t files_lock;
  582. #define file_list_lock() spin_lock(&files_lock);
  583. #define file_list_unlock() spin_unlock(&files_lock);
  584. #define get_file(x) atomic_inc(&(x)->f_count)
  585. #define file_count(x) atomic_read(&(x)->f_count)
  586. #define MAX_NON_LFS ((1UL<<31) - 1)
  587. /* Page cache limit. The filesystems should put that into their s_maxbytes
  588. limits, otherwise bad things can happen in VM. */
  589. #if BITS_PER_LONG==32
  590. #define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
  591. #elif BITS_PER_LONG==64
  592. #define MAX_LFS_FILESIZE 0x7fffffffffffffffUL
  593. #endif
  594. #define FL_POSIX 1
  595. #define FL_FLOCK 2
  596. #define FL_ACCESS 8 /* not trying to lock, just looking */
  597. #define FL_LOCKD 16 /* lock held by rpc.lockd */
  598. #define FL_LEASE 32 /* lease held on this file */
  599. #define FL_SLEEP 128 /* A blocking lock */
  600. /*
  601. * The POSIX file lock owner is determined by
  602. * the "struct files_struct" in the thread group
  603. * (or NULL for no owner - BSD locks).
  604. *
  605. * Lockd stuffs a "host" pointer into this.
  606. */
  607. typedef struct files_struct *fl_owner_t;
  608. struct file_lock_operations {
  609. void (*fl_insert)(struct file_lock *); /* lock insertion callback */
  610. void (*fl_remove)(struct file_lock *); /* lock removal callback */
  611. void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
  612. void (*fl_release_private)(struct file_lock *);
  613. };
  614. struct lock_manager_operations {
  615. int (*fl_compare_owner)(struct file_lock *, struct file_lock *);
  616. void (*fl_notify)(struct file_lock *); /* unblock callback */
  617. void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
  618. void (*fl_release_private)(struct file_lock *);
  619. void (*fl_break)(struct file_lock *);
  620. int (*fl_mylease)(struct file_lock *, struct file_lock *);
  621. int (*fl_change)(struct file_lock **, int);
  622. };
  623. /* that will die - we need it for nfs_lock_info */
  624. #include <linux/nfs_fs_i.h>
  625. struct file_lock {
  626. struct file_lock *fl_next; /* singly linked list for this inode */
  627. struct list_head fl_link; /* doubly linked list of all locks */
  628. struct list_head fl_block; /* circular list of blocked processes */
  629. fl_owner_t fl_owner;
  630. unsigned int fl_pid;
  631. wait_queue_head_t fl_wait;
  632. struct file *fl_file;
  633. unsigned char fl_flags;
  634. unsigned char fl_type;
  635. loff_t fl_start;
  636. loff_t fl_end;
  637. struct fasync_struct * fl_fasync; /* for lease break notifications */
  638. unsigned long fl_break_time; /* for nonblocking lease breaks */
  639. struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
  640. struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
  641. union {
  642. struct nfs_lock_info nfs_fl;
  643. struct nfs4_lock_info nfs4_fl;
  644. } fl_u;
  645. };
  646. /* The following constant reflects the upper bound of the file/locking space */
  647. #ifndef OFFSET_MAX
  648. #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
  649. #define OFFSET_MAX INT_LIMIT(loff_t)
  650. #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
  651. #endif
  652. extern struct list_head file_lock_list;
  653. #include <linux/fcntl.h>
  654. extern int fcntl_getlk(struct file *, struct flock __user *);
  655. extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
  656. struct flock __user *);
  657. #if BITS_PER_LONG == 32
  658. extern int fcntl_getlk64(struct file *, struct flock64 __user *);
  659. extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
  660. struct flock64 __user *);
  661. #endif
  662. extern void send_sigio(struct fown_struct *fown, int fd, int band);
  663. extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
  664. extern int fcntl_getlease(struct file *filp);
  665. /* fs/locks.c */
  666. extern void locks_init_lock(struct file_lock *);
  667. extern void locks_copy_lock(struct file_lock *, struct file_lock *);
  668. extern void locks_remove_posix(struct file *, fl_owner_t);
  669. extern void locks_remove_flock(struct file *);
  670. extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
  671. extern int posix_lock_file(struct file *, struct file_lock *);
  672. extern int posix_lock_file_wait(struct file *, struct file_lock *);
  673. extern void posix_block_lock(struct file_lock *, struct file_lock *);
  674. extern int posix_unblock_lock(struct file *, struct file_lock *);
  675. extern int posix_locks_deadlock(struct file_lock *, struct file_lock *);
  676. extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
  677. extern int __break_lease(struct inode *inode, unsigned int flags);
  678. extern void lease_get_mtime(struct inode *, struct timespec *time);
  679. extern int setlease(struct file *, long, struct file_lock **);
  680. extern int lease_modify(struct file_lock **, int);
  681. extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
  682. extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
  683. extern void steal_locks(fl_owner_t from);
  684. struct fasync_struct {
  685. int magic;
  686. int fa_fd;
  687. struct fasync_struct *fa_next; /* singly linked list */
  688. struct file *fa_file;
  689. };
  690. #define FASYNC_MAGIC 0x4601
  691. /* SMP safe fasync helpers: */
  692. extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
  693. /* can be called from interrupts */
  694. extern void kill_fasync(struct fasync_struct **, int, int);
  695. /* only for net: no internal synchronization */
  696. extern void __kill_fasync(struct fasync_struct *, int, int);
  697. extern int f_setown(struct file *filp, unsigned long arg, int force);
  698. extern void f_delown(struct file *filp);
  699. extern int send_sigurg(struct fown_struct *fown);
  700. /*
  701. * Umount options
  702. */
  703. #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
  704. #define MNT_DETACH 0x00000002 /* Just detach from the tree */
  705. #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
  706. extern struct list_head super_blocks;
  707. extern spinlock_t sb_lock;
  708. #define sb_entry(list) list_entry((list), struct super_block, s_list)
  709. #define S_BIAS (1<<30)
  710. struct super_block {
  711. struct list_head s_list; /* Keep this first */
  712. dev_t s_dev; /* search index; _not_ kdev_t */
  713. unsigned long s_blocksize;
  714. unsigned char s_blocksize_bits;
  715. unsigned char s_dirt;
  716. unsigned long long s_maxbytes; /* Max file size */
  717. struct file_system_type *s_type;
  718. struct super_operations *s_op;
  719. struct dquot_operations *dq_op;
  720. struct quotactl_ops *s_qcop;
  721. struct export_operations *s_export_op;
  722. unsigned long s_flags;
  723. unsigned long s_magic;
  724. struct dentry *s_root;
  725. struct rw_semaphore s_umount;
  726. struct mutex s_lock;
  727. int s_count;
  728. int s_syncing;
  729. int s_need_sync_fs;
  730. atomic_t s_active;
  731. void *s_security;
  732. struct xattr_handler **s_xattr;
  733. struct list_head s_inodes; /* all inodes */
  734. struct list_head s_dirty; /* dirty inodes */
  735. struct list_head s_io; /* parked for writeback */
  736. struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */
  737. struct list_head s_files;
  738. struct block_device *s_bdev;
  739. struct list_head s_instances;
  740. struct quota_info s_dquot; /* Diskquota specific options */
  741. int s_frozen;
  742. wait_queue_head_t s_wait_unfrozen;
  743. char s_id[32]; /* Informational name */
  744. void *s_fs_info; /* Filesystem private info */
  745. /*
  746. * The next field is for VFS *only*. No filesystems have any business
  747. * even looking at it. You had been warned.
  748. */
  749. struct mutex s_vfs_rename_mutex; /* Kludge */
  750. /* Granuality of c/m/atime in ns.
  751. Cannot be worse than a second */
  752. u32 s_time_gran;
  753. };
  754. extern struct timespec current_fs_time(struct super_block *sb);
  755. /*
  756. * Snapshotting support.
  757. */
  758. enum {
  759. SB_UNFROZEN = 0,
  760. SB_FREEZE_WRITE = 1,
  761. SB_FREEZE_TRANS = 2,
  762. };
  763. #define vfs_check_frozen(sb, level) \
  764. wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level)))
  765. static inline void get_fs_excl(void)
  766. {
  767. atomic_inc(&current->fs_excl);
  768. }
  769. static inline void put_fs_excl(void)
  770. {
  771. atomic_dec(&current->fs_excl);
  772. }
  773. static inline int has_fs_excl(void)
  774. {
  775. return atomic_read(&current->fs_excl);
  776. }
  777. /*
  778. * Superblock locking.
  779. */
  780. static inline void lock_super(struct super_block * sb)
  781. {
  782. get_fs_excl();
  783. mutex_lock(&sb->s_lock);
  784. }
  785. static inline void unlock_super(struct super_block * sb)
  786. {
  787. put_fs_excl();
  788. mutex_unlock(&sb->s_lock);
  789. }
  790. /*
  791. * VFS helper functions..
  792. */
  793. extern int vfs_permission(struct nameidata *, int);
  794. extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *);
  795. extern int vfs_mkdir(struct inode *, struct dentry *, int);
  796. extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
  797. extern int vfs_symlink(struct inode *, struct dentry *, const char *, int);
  798. extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
  799. extern int vfs_rmdir(struct inode *, struct dentry *);
  800. extern int vfs_unlink(struct inode *, struct dentry *);
  801. extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
  802. /*
  803. * VFS dentry helper functions.
  804. */
  805. extern void dentry_unhash(struct dentry *dentry);
  806. /*
  807. * VFS file helper functions.
  808. */
  809. extern int file_permission(struct file *, int);
  810. /*
  811. * File types
  812. *
  813. * NOTE! These match bits 12..15 of stat.st_mode
  814. * (ie "(i_mode >> 12) & 15").
  815. */
  816. #define DT_UNKNOWN 0
  817. #define DT_FIFO 1
  818. #define DT_CHR 2
  819. #define DT_DIR 4
  820. #define DT_BLK 6
  821. #define DT_REG 8
  822. #define DT_LNK 10
  823. #define DT_SOCK 12
  824. #define DT_WHT 14
  825. #define OSYNC_METADATA (1<<0)
  826. #define OSYNC_DATA (1<<1)
  827. #define OSYNC_INODE (1<<2)
  828. int generic_osync_inode(struct inode *, struct address_space *, int);
  829. /*
  830. * This is the "filldir" function type, used by readdir() to let
  831. * the kernel specify what kind of dirent layout it wants to have.
  832. * This allows the kernel to read directories into kernel space or
  833. * to have different dirent layouts depending on the binary type.
  834. */
  835. typedef int (*filldir_t)(void *, const char *, int, loff_t, ino_t, unsigned);
  836. struct block_device_operations {
  837. int (*open) (struct inode *, struct file *);
  838. int (*release) (struct inode *, struct file *);
  839. int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
  840. long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
  841. long (*compat_ioctl) (struct file *, unsigned, unsigned long);
  842. int (*direct_access) (struct block_device *, sector_t, unsigned long *);
  843. int (*media_changed) (struct gendisk *);
  844. int (*revalidate_disk) (struct gendisk *);
  845. int (*getgeo)(struct block_device *, struct hd_geometry *);
  846. struct module *owner;
  847. };
  848. /*
  849. * "descriptor" for what we're up to with a read for sendfile().
  850. * This allows us to use the same read code yet
  851. * have multiple different users of the data that
  852. * we read from a file.
  853. *
  854. * The simplest case just copies the data to user
  855. * mode.
  856. */
  857. typedef struct {
  858. size_t written;
  859. size_t count;
  860. union {
  861. char __user * buf;
  862. void *data;
  863. } arg;
  864. int error;
  865. } read_descriptor_t;
  866. typedef int (*read_actor_t)(read_descriptor_t *, struct page *, unsigned long, unsigned long);
  867. /* These macros are for out of kernel modules to test that
  868. * the kernel supports the unlocked_ioctl and compat_ioctl
  869. * fields in struct file_operations. */
  870. #define HAVE_COMPAT_IOCTL 1
  871. #define HAVE_UNLOCKED_IOCTL 1
  872. /*
  873. * NOTE:
  874. * read, write, poll, fsync, readv, writev, unlocked_ioctl and compat_ioctl
  875. * can be called without the big kernel lock held in all filesystems.
  876. */
  877. struct file_operations {
  878. struct module *owner;
  879. loff_t (*llseek) (struct file *, loff_t, int);
  880. ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
  881. ssize_t (*aio_read) (struct kiocb *, char __user *, size_t, loff_t);
  882. ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
  883. ssize_t (*aio_write) (struct kiocb *, const char __user *, size_t, loff_t);
  884. int (*readdir) (struct file *, void *, filldir_t);
  885. unsigned int (*poll) (struct file *, struct poll_table_struct *);
  886. int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
  887. long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
  888. long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
  889. int (*mmap) (struct file *, struct vm_area_struct *);
  890. int (*open) (struct inode *, struct file *);
  891. int (*flush) (struct file *);
  892. int (*release) (struct inode *, struct file *);
  893. int (*fsync) (struct file *, struct dentry *, int datasync);
  894. int (*aio_fsync) (struct kiocb *, int datasync);
  895. int (*fasync) (int, struct file *, int);
  896. int (*lock) (struct file *, int, struct file_lock *);
  897. ssize_t (*readv) (struct file *, const struct iovec *, unsigned long, loff_t *);
  898. ssize_t (*writev) (struct file *, const struct iovec *, unsigned long, loff_t *);
  899. ssize_t (*sendfile) (struct file *, loff_t *, size_t, read_actor_t, void *);
  900. ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
  901. unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
  902. int (*check_flags)(int);
  903. int (*dir_notify)(struct file *filp, unsigned long arg);
  904. int (*flock) (struct file *, int, struct file_lock *);
  905. };
  906. struct inode_operations {
  907. int (*create) (struct inode *,struct dentry *,int, struct nameidata *);
  908. struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *);
  909. int (*link) (struct dentry *,struct inode *,struct dentry *);
  910. int (*unlink) (struct inode *,struct dentry *);
  911. int (*symlink) (struct inode *,struct dentry *,const char *);
  912. int (*mkdir) (struct inode *,struct dentry *,int);
  913. int (*rmdir) (struct inode *,struct dentry *);
  914. int (*mknod) (struct inode *,struct dentry *,int,dev_t);
  915. int (*rename) (struct inode *, struct dentry *,
  916. struct inode *, struct dentry *);
  917. int (*readlink) (struct dentry *, char __user *,int);
  918. void * (*follow_link) (struct dentry *, struct nameidata *);
  919. void (*put_link) (struct dentry *, struct nameidata *, void *);
  920. void (*truncate) (struct inode *);
  921. int (*permission) (struct inode *, int, struct nameidata *);
  922. int (*setattr) (struct dentry *, struct iattr *);
  923. int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
  924. int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
  925. ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
  926. ssize_t (*listxattr) (struct dentry *, char *, size_t);
  927. int (*removexattr) (struct dentry *, const char *);
  928. void (*truncate_range)(struct inode *, loff_t, loff_t);
  929. };
  930. struct seq_file;
  931. extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
  932. extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
  933. extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
  934. unsigned long, loff_t *);
  935. extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
  936. unsigned long, loff_t *);
  937. /*
  938. * NOTE: write_inode, delete_inode, clear_inode, put_inode can be called
  939. * without the big kernel lock held in all filesystems.
  940. */
  941. struct super_operations {
  942. struct inode *(*alloc_inode)(struct super_block *sb);
  943. void (*destroy_inode)(struct inode *);
  944. void (*read_inode) (struct inode *);
  945. void (*dirty_inode) (struct inode *);
  946. int (*write_inode) (struct inode *, int);
  947. void (*put_inode) (struct inode *);
  948. void (*drop_inode) (struct inode *);
  949. void (*delete_inode) (struct inode *);
  950. void (*put_super) (struct super_block *);
  951. void (*write_super) (struct super_block *);
  952. int (*sync_fs)(struct super_block *sb, int wait);
  953. void (*write_super_lockfs) (struct super_block *);
  954. void (*unlockfs) (struct super_block *);
  955. int (*statfs) (struct super_block *, struct kstatfs *);
  956. int (*remount_fs) (struct super_block *, int *, char *);
  957. void (*clear_inode) (struct inode *);
  958. void (*umount_begin) (struct super_block *);
  959. int (*show_options)(struct seq_file *, struct vfsmount *);
  960. ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
  961. ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
  962. };
  963. /* Inode state bits. Protected by inode_lock. */
  964. #define I_DIRTY_SYNC 1 /* Not dirty enough for O_DATASYNC */
  965. #define I_DIRTY_DATASYNC 2 /* Data-related inode changes pending */
  966. #define I_DIRTY_PAGES 4 /* Data-related inode changes pending */
  967. #define __I_LOCK 3
  968. #define I_LOCK (1 << __I_LOCK)
  969. #define I_FREEING 16
  970. #define I_CLEAR 32
  971. #define I_NEW 64
  972. #define I_WILL_FREE 128
  973. #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
  974. extern void __mark_inode_dirty(struct inode *, int);
  975. static inline void mark_inode_dirty(struct inode *inode)
  976. {
  977. __mark_inode_dirty(inode, I_DIRTY);
  978. }
  979. static inline void mark_inode_dirty_sync(struct inode *inode)
  980. {
  981. __mark_inode_dirty(inode, I_DIRTY_SYNC);
  982. }
  983. static inline void inode_inc_link_count(struct inode *inode)
  984. {
  985. inode->i_nlink++;
  986. mark_inode_dirty(inode);
  987. }
  988. static inline void inode_dec_link_count(struct inode *inode)
  989. {
  990. inode->i_nlink--;
  991. mark_inode_dirty(inode);
  992. }
  993. extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry);
  994. static inline void file_accessed(struct file *file)
  995. {
  996. if (!(file->f_flags & O_NOATIME))
  997. touch_atime(file->f_vfsmnt, file->f_dentry);
  998. }
  999. int sync_inode(struct inode *inode, struct writeback_control *wbc);
  1000. /**
  1001. * struct export_operations - for nfsd to communicate with file systems
  1002. * @decode_fh: decode a file handle fragment and return a &struct dentry
  1003. * @encode_fh: encode a file handle fragment from a dentry
  1004. * @get_name: find the name for a given inode in a given directory
  1005. * @get_parent: find the parent of a given directory
  1006. * @get_dentry: find a dentry for the inode given a file handle sub-fragment
  1007. * @find_exported_dentry:
  1008. * set by the exporting module to a standard helper function.
  1009. *
  1010. * Description:
  1011. * The export_operations structure provides a means for nfsd to communicate
  1012. * with a particular exported file system - particularly enabling nfsd and
  1013. * the filesystem to co-operate when dealing with file handles.
  1014. *
  1015. * export_operations contains two basic operation for dealing with file
  1016. * handles, decode_fh() and encode_fh(), and allows for some other
  1017. * operations to be defined which standard helper routines use to get
  1018. * specific information from the filesystem.
  1019. *
  1020. * nfsd encodes information use to determine which filesystem a filehandle
  1021. * applies to in the initial part of the file handle. The remainder, termed
  1022. * a file handle fragment, is controlled completely by the filesystem. The
  1023. * standard helper routines assume that this fragment will contain one or
  1024. * two sub-fragments, one which identifies the file, and one which may be
  1025. * used to identify the (a) directory containing the file.
  1026. *
  1027. * In some situations, nfsd needs to get a dentry which is connected into a
  1028. * specific part of the file tree. To allow for this, it passes the
  1029. * function acceptable() together with a @context which can be used to see
  1030. * if the dentry is acceptable. As there can be multiple dentrys for a
  1031. * given file, the filesystem should check each one for acceptability before
  1032. * looking for the next. As soon as an acceptable one is found, it should
  1033. * be returned.
  1034. *
  1035. * decode_fh:
  1036. * @decode_fh is given a &struct super_block (@sb), a file handle fragment
  1037. * (@fh, @fh_len) and an acceptability testing function (@acceptable,
  1038. * @context). It should return a &struct dentry which refers to the same
  1039. * file that the file handle fragment refers to, and which passes the
  1040. * acceptability test. If it cannot, it should return a %NULL pointer if
  1041. * the file was found but no acceptable &dentries were available, or a
  1042. * %ERR_PTR error code indicating why it couldn't be found (e.g. %ENOENT or
  1043. * %ENOMEM).
  1044. *
  1045. * encode_fh:
  1046. * @encode_fh should store in the file handle fragment @fh (using at most
  1047. * @max_len bytes) information that can be used by @decode_fh to recover the
  1048. * file refered to by the &struct dentry @de. If the @connectable flag is
  1049. * set, the encode_fh() should store sufficient information so that a good
  1050. * attempt can be made to find not only the file but also it's place in the
  1051. * filesystem. This typically means storing a reference to de->d_parent in
  1052. * the filehandle fragment. encode_fh() should return the number of bytes
  1053. * stored or a negative error code such as %-ENOSPC
  1054. *
  1055. * get_name:
  1056. * @get_name should find a name for the given @child in the given @parent
  1057. * directory. The name should be stored in the @name (with the
  1058. * understanding that it is already pointing to a a %NAME_MAX+1 sized
  1059. * buffer. get_name() should return %0 on success, a negative error code
  1060. * or error. @get_name will be called without @parent->i_mutex held.
  1061. *
  1062. * get_parent:
  1063. * @get_parent should find the parent directory for the given @child which
  1064. * is also a directory. In the event that it cannot be found, or storage
  1065. * space cannot be allocated, a %ERR_PTR should be returned.
  1066. *
  1067. * get_dentry:
  1068. * Given a &super_block (@sb) and a pointer to a file-system specific inode
  1069. * identifier, possibly an inode number, (@inump) get_dentry() should find
  1070. * the identified inode and return a dentry for that inode. Any suitable
  1071. * dentry can be returned including, if necessary, a new dentry created with
  1072. * d_alloc_root. The caller can then find any other extant dentrys by
  1073. * following the d_alias links. If a new dentry was created using
  1074. * d_alloc_root, DCACHE_NFSD_DISCONNECTED should be set, and the dentry
  1075. * should be d_rehash()ed.
  1076. *
  1077. * If the inode cannot be found, either a %NULL pointer or an %ERR_PTR code
  1078. * can be returned. The @inump will be whatever was passed to
  1079. * nfsd_find_fh_dentry() in either the @obj or @parent parameters.
  1080. *
  1081. * Locking rules:
  1082. * get_parent is called with child->d_inode->i_mutex down
  1083. * get_name is not (which is possibly inconsistent)
  1084. */
  1085. struct export_operations {
  1086. struct dentry *(*decode_fh)(struct super_block *sb, __u32 *fh, int fh_len, int fh_type,
  1087. int (*acceptable)(void *context, struct dentry *de),
  1088. void *context);
  1089. int (*encode_fh)(struct dentry *de, __u32 *fh, int *max_len,
  1090. int connectable);
  1091. /* the following are only called from the filesystem itself */
  1092. int (*get_name)(struct dentry *parent, char *name,
  1093. struct dentry *child);
  1094. struct dentry * (*get_parent)(struct dentry *child);
  1095. struct dentry * (*get_dentry)(struct super_block *sb, void *inump);
  1096. /* This is set by the exporting module to a standard helper */
  1097. struct dentry * (*find_exported_dentry)(
  1098. struct super_block *sb, void *obj, void *parent,
  1099. int (*acceptable)(void *context, struct dentry *de),
  1100. void *context);
  1101. };
  1102. extern struct dentry *
  1103. find_exported_dentry(struct super_block *sb, void *obj, void *parent,
  1104. int (*acceptable)(void *context, struct dentry *de),
  1105. void *context);
  1106. struct file_system_type {
  1107. const char *name;
  1108. int fs_flags;
  1109. struct super_block *(*get_sb) (struct file_system_type *, int,
  1110. const char *, void *);
  1111. void (*kill_sb) (struct super_block *);
  1112. struct module *owner;
  1113. struct file_system_type * next;
  1114. struct list_head fs_supers;
  1115. };
  1116. struct super_block *get_sb_bdev(struct file_system_type *fs_type,
  1117. int flags, const char *dev_name, void *data,
  1118. int (*fill_super)(struct super_block *, void *, int));
  1119. struct super_block *get_sb_single(struct file_system_type *fs_type,
  1120. int flags, void *data,
  1121. int (*fill_super)(struct super_block *, void *, int));
  1122. struct super_block *get_sb_nodev(struct file_system_type *fs_type,
  1123. int flags, void *data,
  1124. int (*fill_super)(struct super_block *, void *, int));
  1125. void generic_shutdown_super(struct super_block *sb);
  1126. void kill_block_super(struct super_block *sb);
  1127. void kill_anon_super(struct super_block *sb);
  1128. void kill_litter_super(struct super_block *sb);
  1129. void deactivate_super(struct super_block *sb);
  1130. int set_anon_super(struct super_block *s, void *data);
  1131. struct super_block *sget(struct file_system_type *type,
  1132. int (*test)(struct super_block *,void *),
  1133. int (*set)(struct super_block *,void *),
  1134. void *data);
  1135. struct super_block *get_sb_pseudo(struct file_system_type *, char *,
  1136. struct super_operations *ops, unsigned long);
  1137. int __put_super(struct super_block *sb);
  1138. int __put_super_and_need_restart(struct super_block *sb);
  1139. void unnamed_dev_init(void);
  1140. /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
  1141. #define fops_get(fops) \
  1142. (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
  1143. #define fops_put(fops) \
  1144. do { if (fops) module_put((fops)->owner); } while(0)
  1145. extern int register_filesystem(struct file_system_type *);
  1146. extern int unregister_filesystem(struct file_system_type *);
  1147. extern struct vfsmount *kern_mount(struct file_system_type *);
  1148. extern int may_umount_tree(struct vfsmount *);
  1149. extern int may_umount(struct vfsmount *);
  1150. extern void umount_tree(struct vfsmount *, int, struct list_head *);
  1151. extern void release_mounts(struct list_head *);
  1152. extern long do_mount(char *, char *, char *, unsigned long, void *);
  1153. extern struct vfsmount *copy_tree(struct vfsmount *, struct dentry *, int);
  1154. extern void mnt_set_mountpoint(struct vfsmount *, struct dentry *,
  1155. struct vfsmount *);
  1156. extern int vfs_statfs(struct super_block *, struct kstatfs *);
  1157. /* /sys/fs */
  1158. extern struct subsystem fs_subsys;
  1159. #define FLOCK_VERIFY_READ 1
  1160. #define FLOCK_VERIFY_WRITE 2
  1161. extern int locks_mandatory_locked(struct inode *);
  1162. extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
  1163. /*
  1164. * Candidates for mandatory locking have the setgid bit set
  1165. * but no group execute bit - an otherwise meaningless combination.
  1166. */
  1167. #define MANDATORY_LOCK(inode) \
  1168. (IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
  1169. static inline int locks_verify_locked(struct inode *inode)
  1170. {
  1171. if (MANDATORY_LOCK(inode))
  1172. return locks_mandatory_locked(inode);
  1173. return 0;
  1174. }
  1175. extern int rw_verify_area(int, struct file *, loff_t *, size_t);
  1176. static inline int locks_verify_truncate(struct inode *inode,
  1177. struct file *filp,
  1178. loff_t size)
  1179. {
  1180. if (inode->i_flock && MANDATORY_LOCK(inode))
  1181. return locks_mandatory_area(
  1182. FLOCK_VERIFY_WRITE, inode, filp,
  1183. size < inode->i_size ? size : inode->i_size,
  1184. (size < inode->i_size ? inode->i_size - size
  1185. : size - inode->i_size)
  1186. );
  1187. return 0;
  1188. }
  1189. static inline int break_lease(struct inode *inode, unsigned int mode)
  1190. {
  1191. if (inode->i_flock)
  1192. return __break_lease(inode, mode);
  1193. return 0;
  1194. }
  1195. /* fs/open.c */
  1196. extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
  1197. struct file *filp);
  1198. extern long do_sys_open(int fdf, const char __user *filename, int flags,
  1199. int mode);
  1200. extern struct file *filp_open(const char *, int, int);
  1201. extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
  1202. extern int filp_close(struct file *, fl_owner_t id);
  1203. extern char * getname(const char __user *);
  1204. /* fs/dcache.c */
  1205. extern void __init vfs_caches_init_early(void);
  1206. extern void __init vfs_caches_init(unsigned long);
  1207. #define __getname() kmem_cache_alloc(names_cachep, SLAB_KERNEL)
  1208. #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
  1209. #ifndef CONFIG_AUDITSYSCALL
  1210. #define putname(name) __putname(name)
  1211. #else
  1212. extern void putname(const char *name);
  1213. #endif
  1214. extern int register_blkdev(unsigned int, const char *);
  1215. extern int unregister_blkdev(unsigned int, const char *);
  1216. extern struct block_device *bdget(dev_t);
  1217. extern void bd_set_size(struct block_device *, loff_t size);
  1218. extern void bd_forget(struct inode *inode);
  1219. extern void bdput(struct block_device *);
  1220. extern struct block_device *open_by_devnum(dev_t, unsigned);
  1221. extern struct file_operations def_blk_fops;
  1222. extern struct address_space_operations def_blk_aops;
  1223. extern struct file_operations def_chr_fops;
  1224. extern struct file_operations bad_sock_fops;
  1225. extern struct file_operations def_fifo_fops;
  1226. extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
  1227. extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long);
  1228. extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
  1229. extern int blkdev_get(struct block_device *, mode_t, unsigned);
  1230. extern int blkdev_put(struct block_device *);
  1231. extern int bd_claim(struct block_device *, void *);
  1232. extern void bd_release(struct block_device *);
  1233. /* fs/char_dev.c */
  1234. extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
  1235. extern int register_chrdev_region(dev_t, unsigned, const char *);
  1236. extern int register_chrdev(unsigned int, const char *,
  1237. struct file_operations *);
  1238. extern int unregister_chrdev(unsigned int, const char *);
  1239. extern void unregister_chrdev_region(dev_t, unsigned);
  1240. extern int chrdev_open(struct inode *, struct file *);
  1241. extern int get_chrdev_list(char *);
  1242. extern void *acquire_chrdev_list(void);
  1243. extern int count_chrdev_list(void);
  1244. extern void *get_next_chrdev(void *);
  1245. extern int get_chrdev_info(void *, int *, char **);
  1246. extern void release_chrdev_list(void *);
  1247. /* fs/block_dev.c */
  1248. #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
  1249. extern const char *__bdevname(dev_t, char *buffer);
  1250. extern const char *bdevname(struct block_device *bdev, char *buffer);
  1251. extern struct block_device *lookup_bdev(const char *);
  1252. extern struct block_device *open_bdev_excl(const char *, int, void *);
  1253. extern void close_bdev_excl(struct block_device *);
  1254. extern void *acquire_blkdev_list(void);
  1255. extern int count_blkdev_list(void);
  1256. extern void *get_next_blkdev(void *);
  1257. extern int get_blkdev_info(void *, int *, char **);
  1258. extern void release_blkdev_list(void *);
  1259. extern void init_special_inode(struct inode *, umode_t, dev_t);
  1260. /* Invalid inode operations -- fs/bad_inode.c */
  1261. extern void make_bad_inode(struct inode *);
  1262. extern int is_bad_inode(struct inode *);
  1263. extern struct file_operations read_fifo_fops;
  1264. extern struct file_operations write_fifo_fops;
  1265. extern struct file_operations rdwr_fifo_fops;
  1266. extern int fs_may_remount_ro(struct super_block *);
  1267. /*
  1268. * return READ, READA, or WRITE
  1269. */
  1270. #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
  1271. /*
  1272. * return data direction, READ or WRITE
  1273. */
  1274. #define bio_data_dir(bio) ((bio)->bi_rw & 1)
  1275. extern int check_disk_change(struct block_device *);
  1276. extern int invalidate_inodes(struct super_block *);
  1277. extern int __invalidate_device(struct block_device *);
  1278. extern int invalidate_partition(struct gendisk *, int);
  1279. unsigned long invalidate_mapping_pages(struct address_space *mapping,
  1280. pgoff_t start, pgoff_t end);
  1281. unsigned long invalidate_inode_pages(struct address_space *mapping);
  1282. static inline void invalidate_remote_inode(struct inode *inode)
  1283. {
  1284. if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
  1285. S_ISLNK(inode->i_mode))
  1286. invalidate_inode_pages(inode->i_mapping);
  1287. }
  1288. extern int invalidate_inode_pages2(struct address_space *mapping);
  1289. extern int invalidate_inode_pages2_range(struct address_space *mapping,
  1290. pgoff_t start, pgoff_t end);
  1291. extern int write_inode_now(struct inode *, int);
  1292. extern int filemap_fdatawrite(struct address_space *);
  1293. extern int filemap_flush(struct address_space *);
  1294. extern int filemap_fdatawait(struct address_space *);
  1295. extern int filemap_write_and_wait(struct address_space *mapping);
  1296. extern int filemap_write_and_wait_range(struct address_space *mapping,
  1297. loff_t lstart, loff_t lend);
  1298. extern int wait_on_page_writeback_range(struct address_space *mapping,
  1299. pgoff_t start, pgoff_t end);
  1300. extern int __filemap_fdatawrite_range(struct address_space *mapping,
  1301. loff_t start, loff_t end, int sync_mode);
  1302. extern long do_fsync(struct file *file, int datasync);
  1303. extern void sync_supers(void);
  1304. extern void sync_filesystems(int wait);
  1305. extern void emergency_sync(void);
  1306. extern void emergency_remount(void);
  1307. extern int do_remount_sb(struct super_block *sb, int flags,
  1308. void *data, int force);
  1309. extern sector_t bmap(struct inode *, sector_t);
  1310. extern int notify_change(struct dentry *, struct iattr *);
  1311. extern int permission(struct inode *, int, struct nameidata *);
  1312. extern int generic_permission(struct inode *, int,
  1313. int (*check_acl)(struct inode *, int));
  1314. extern int get_write_access(struct inode *);
  1315. extern int deny_write_access(struct file *);
  1316. static inline void put_write_access(struct inode * inode)
  1317. {
  1318. atomic_dec(&inode->i_writecount);
  1319. }
  1320. static inline void allow_write_access(struct file *file)
  1321. {
  1322. if (file)
  1323. atomic_inc(&file->f_dentry->d_inode->i_writecount);
  1324. }
  1325. extern int do_pipe(int *);
  1326. extern int open_namei(int dfd, const char *, int, int, struct nameidata *);
  1327. extern int may_open(struct nameidata *, int, int);
  1328. extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
  1329. extern struct file * open_exec(const char *);
  1330. /* fs/dcache.c -- generic fs support functions */
  1331. extern int is_subdir(struct dentry *, struct dentry *);
  1332. extern ino_t find_inode_number(struct dentry *, struct qstr *);
  1333. #include <linux/err.h>
  1334. /* needed for stackable file system support */
  1335. extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
  1336. extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
  1337. extern void inode_init_once(struct inode *);
  1338. extern void iput(struct inode *);
  1339. extern struct inode * igrab(struct inode *);
  1340. extern ino_t iunique(struct super_block *, ino_t);
  1341. extern int inode_needs_sync(struct inode *inode);
  1342. extern void generic_delete_inode(struct inode *inode);
  1343. extern void generic_drop_inode(struct inode *inode);
  1344. extern struct inode *ilookup5_nowait(struct super_block *sb,
  1345. unsigned long hashval, int (*test)(struct inode *, void *),
  1346. void *data);
  1347. extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
  1348. int (*test)(struct inode *, void *), void *data);
  1349. extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
  1350. extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
  1351. extern struct inode * iget_locked(struct super_block *, unsigned long);
  1352. extern void unlock_new_inode(struct inode *);
  1353. static inline struct inode *iget(struct super_block *sb, unsigned long ino)
  1354. {
  1355. struct inode *inode = iget_locked(sb, ino);
  1356. if (inode && (inode->i_state & I_NEW)) {
  1357. sb->s_op->read_inode(inode);
  1358. unlock_new_inode(inode);
  1359. }
  1360. return inode;
  1361. }
  1362. extern void __iget(struct inode * inode);
  1363. extern void clear_inode(struct inode *);
  1364. extern void destroy_inode(struct inode *);
  1365. extern struct inode *new_inode(struct super_block *);
  1366. extern int remove_suid(struct dentry *);
  1367. extern void remove_dquot_ref(struct super_block *, int, struct list_head *);
  1368. extern struct mutex iprune_mutex;
  1369. extern void __insert_inode_hash(struct inode *, unsigned long hashval);
  1370. extern void remove_inode_hash(struct inode *);
  1371. static inline void insert_inode_hash(struct inode *inode) {
  1372. __insert_inode_hash(inode, inode->i_ino);
  1373. }
  1374. extern struct file * get_empty_filp(void);
  1375. extern void file_move(struct file *f, struct list_head *list);
  1376. extern void file_kill(struct file *f);
  1377. struct bio;
  1378. extern void submit_bio(int, struct bio *);
  1379. extern int bdev_read_only(struct block_device *);
  1380. extern int set_blocksize(struct block_device *, int);
  1381. extern int sb_set_blocksize(struct super_block *, int);
  1382. extern int sb_min_blocksize(struct super_block *, int);
  1383. extern int generic_file_mmap(struct file *, struct vm_area_struct *);
  1384. extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
  1385. extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
  1386. extern int file_send_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
  1387. extern ssize_t generic_file_read(struct file *, char __user *, size_t, loff_t *);
  1388. int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
  1389. extern ssize_t generic_file_write(struct file *, const char __user *, size_t, loff_t *);
  1390. extern ssize_t generic_file_aio_read(struct kiocb *, char __user *, size_t, loff_t);
  1391. extern ssize_t __generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t *);
  1392. extern ssize_t generic_file_aio_write(struct kiocb *, const char __user *, size_t, loff_t);
  1393. extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
  1394. unsigned long, loff_t *);
  1395. extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
  1396. unsigned long *, loff_t, loff_t *, size_t, size_t);
  1397. extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
  1398. unsigned long, loff_t, loff_t *, size_t, ssize_t);
  1399. extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
  1400. extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
  1401. ssize_t generic_file_write_nolock(struct file *file, const struct iovec *iov,
  1402. unsigned long nr_segs, loff_t *ppos);
  1403. extern ssize_t generic_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);
  1404. extern void do_generic_mapping_read(struct address_space *mapping,
  1405. struct file_ra_state *, struct file *,
  1406. loff_t *, read_descriptor_t *, read_actor_t);
  1407. extern void
  1408. file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
  1409. extern ssize_t generic_file_readv(struct file *filp, const struct iovec *iov,
  1410. unsigned long nr_segs, loff_t *ppos);
  1411. ssize_t generic_file_writev(struct file *filp, const struct iovec *iov,
  1412. unsigned long nr_segs, loff_t *ppos);
  1413. extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
  1414. extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
  1415. extern loff_t remote_llseek(struct file *file, loff_t offset, int origin);
  1416. extern int generic_file_open(struct inode * inode, struct file * filp);
  1417. extern int nonseekable_open(struct inode * inode, struct file * filp);
  1418. #ifdef CONFIG_FS_XIP
  1419. extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
  1420. loff_t *ppos);
  1421. extern ssize_t xip_file_sendfile(struct file *in_file, loff_t *ppos,
  1422. size_t count, read_actor_t actor,
  1423. void *target);
  1424. extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
  1425. extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
  1426. size_t len, loff_t *ppos);
  1427. extern int xip_truncate_page(struct address_space *mapping, loff_t from);
  1428. #else
  1429. static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
  1430. {
  1431. return 0;
  1432. }
  1433. #endif
  1434. static inline void do_generic_file_read(struct file * filp, loff_t *ppos,
  1435. read_descriptor_t * desc,
  1436. read_actor_t actor)
  1437. {
  1438. do_generic_mapping_read(filp->f_mapping,
  1439. &filp->f_ra,
  1440. filp,
  1441. ppos,
  1442. desc,
  1443. actor);
  1444. }
  1445. ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
  1446. struct block_device *bdev, const struct iovec *iov, loff_t offset,
  1447. unsigned long nr_segs, get_blocks_t get_blocks, dio_iodone_t end_io,
  1448. int lock_type);
  1449. enum {
  1450. DIO_LOCKING = 1, /* need locking between buffered and direct access */
  1451. DIO_NO_LOCKING, /* bdev; no locking at all between buffered/direct */
  1452. DIO_OWN_LOCKING, /* filesystem locks buffered and direct internally */
  1453. };
  1454. static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
  1455. struct inode *inode, struct block_device *bdev, const struct iovec *iov,
  1456. loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
  1457. dio_iodone_t end_io)
  1458. {
  1459. return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
  1460. nr_segs, get_blocks, end_io, DIO_LOCKING);
  1461. }
  1462. static inline ssize_t blockdev_direct_IO_no_locking(int rw, struct kiocb *iocb,
  1463. struct inode *inode, struct block_device *bdev, const struct iovec *iov,
  1464. loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
  1465. dio_iodone_t end_io)
  1466. {
  1467. return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
  1468. nr_segs, get_blocks, end_io, DIO_NO_LOCKING);
  1469. }
  1470. static inline ssize_t blockdev_direct_IO_own_locking(int rw, struct kiocb *iocb,
  1471. struct inode *inode, struct block_device *bdev, const struct iovec *iov,
  1472. loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
  1473. dio_iodone_t end_io)
  1474. {
  1475. return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
  1476. nr_segs, get_blocks, end_io, DIO_OWN_LOCKING);
  1477. }
  1478. extern struct file_operations generic_ro_fops;
  1479. #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
  1480. extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
  1481. extern int vfs_follow_link(struct nameidata *, const char *);
  1482. extern int page_readlink(struct dentry *, char __user *, int);
  1483. extern void *page_follow_link_light(struct dentry *, struct nameidata *);
  1484. extern void page_put_link(struct dentry *, struct nameidata *, void *);
  1485. extern int __page_symlink(struct inode *inode, const char *symname, int len,
  1486. gfp_t gfp_mask);
  1487. extern int page_symlink(struct inode *inode, const char *symname, int len);
  1488. extern struct inode_operations page_symlink_inode_operations;
  1489. extern int generic_readlink(struct dentry *, char __user *, int);
  1490. extern void generic_fillattr(struct inode *, struct kstat *);
  1491. extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
  1492. void inode_add_bytes(struct inode *inode, loff_t bytes);
  1493. void inode_sub_bytes(struct inode *inode, loff_t bytes);
  1494. loff_t inode_get_bytes(struct inode *inode);
  1495. void inode_set_bytes(struct inode *inode, loff_t bytes);
  1496. extern int vfs_readdir(struct file *, filldir_t, void *);
  1497. extern int vfs_stat(char __user *, struct kstat *);
  1498. extern int vfs_lstat(char __user *, struct kstat *);
  1499. extern int vfs_stat_fd(int dfd, char __user *, struct kstat *);
  1500. extern int vfs_lstat_fd(int dfd, char __user *, struct kstat *);
  1501. extern int vfs_fstat(unsigned int, struct kstat *);
  1502. extern int vfs_ioctl(struct file *, unsigned int, unsigned int, unsigned long);
  1503. extern struct file_system_type *get_fs_type(const char *name);
  1504. extern struct super_block *get_super(struct block_device *);
  1505. extern struct super_block *user_get_super(dev_t);
  1506. extern void drop_super(struct super_block *sb);
  1507. extern int dcache_dir_open(struct inode *, struct file *);
  1508. extern int dcache_dir_close(struct inode *, struct file *);
  1509. extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
  1510. extern int dcache_readdir(struct file *, void *, filldir_t);
  1511. extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
  1512. extern int simple_statfs(struct super_block *, struct kstatfs *);
  1513. extern int simple_link(struct dentry *, struct inode *, struct dentry *);
  1514. extern int simple_unlink(struct inode *, struct dentry *);
  1515. extern int simple_rmdir(struct inode *, struct dentry *);
  1516. extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
  1517. extern int simple_sync_file(struct file *, struct dentry *, int);
  1518. extern int simple_empty(struct dentry *);
  1519. extern int simple_readpage(struct file *file, struct page *page);
  1520. extern int simple_prepare_write(struct file *file, struct page *page,
  1521. unsigned offset, unsigned to);
  1522. extern int simple_commit_write(struct file *file, struct page *page,
  1523. unsigned offset, unsigned to);
  1524. extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
  1525. extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
  1526. extern struct file_operations simple_dir_operations;
  1527. extern struct inode_operations simple_dir_inode_operations;
  1528. struct tree_descr { char *name; struct file_operations *ops; int mode; };
  1529. struct dentry *d_alloc_name(struct dentry *, const char *);
  1530. extern int simple_fill_super(struct super_block *, int, struct tree_descr *);
  1531. extern int simple_pin_fs(char *name, struct vfsmount **mount, int *count);
  1532. extern void simple_release_fs(struct vfsmount **mount, int *count);
  1533. extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t);
  1534. #ifdef CONFIG_MIGRATION
  1535. extern int buffer_migrate_page(struct page *, struct page *);
  1536. #else
  1537. #define buffer_migrate_page NULL
  1538. #endif
  1539. extern int inode_change_ok(struct inode *, struct iattr *);
  1540. extern int __must_check inode_setattr(struct inode *, struct iattr *);
  1541. extern void file_update_time(struct file *file);
  1542. static inline ino_t parent_ino(struct dentry *dentry)
  1543. {
  1544. ino_t res;
  1545. spin_lock(&dentry->d_lock);
  1546. res = dentry->d_parent->d_inode->i_ino;
  1547. spin_unlock(&dentry->d_lock);
  1548. return res;
  1549. }
  1550. /* kernel/fork.c */
  1551. extern int unshare_files(void);
  1552. /* Transaction based IO helpers */
  1553. /*
  1554. * An argresp is stored in an allocated page and holds the
  1555. * size of the argument or response, along with its content
  1556. */
  1557. struct simple_transaction_argresp {
  1558. ssize_t size;
  1559. char data[0];
  1560. };
  1561. #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
  1562. char *simple_transaction_get(struct file *file, const char __user *buf,
  1563. size_t size);
  1564. ssize_t simple_transaction_read(struct file *file, char __user *buf,
  1565. size_t size, loff_t *pos);
  1566. int simple_transaction_release(struct inode *inode, struct file *file);
  1567. static inline void simple_transaction_set(struct file *file, size_t n)
  1568. {
  1569. struct simple_transaction_argresp *ar = file->private_data;
  1570. BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
  1571. /*
  1572. * The barrier ensures that ar->size will really remain zero until
  1573. * ar->data is ready for reading.
  1574. */
  1575. smp_mb();
  1576. ar->size = n;
  1577. }
  1578. /*
  1579. * simple attribute files
  1580. *
  1581. * These attributes behave similar to those in sysfs:
  1582. *
  1583. * Writing to an attribute immediately sets a value, an open file can be
  1584. * written to multiple times.
  1585. *
  1586. * Reading from an attribute creates a buffer from the value that might get
  1587. * read with multiple read calls. When the attribute has been read
  1588. * completely, no further read calls are possible until the file is opened
  1589. * again.
  1590. *
  1591. * All attributes contain a text representation of a numeric value
  1592. * that are accessed with the get() and set() functions.
  1593. */
  1594. #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
  1595. static int __fops ## _open(struct inode *inode, struct file *file) \
  1596. { \
  1597. __simple_attr_check_format(__fmt, 0ull); \
  1598. return simple_attr_open(inode, file, __get, __set, __fmt); \
  1599. } \
  1600. static struct file_operations __fops = { \
  1601. .owner = THIS_MODULE, \
  1602. .open = __fops ## _open, \
  1603. .release = simple_attr_close, \
  1604. .read = simple_attr_read, \
  1605. .write = simple_attr_write, \
  1606. };
  1607. static inline void __attribute__((format(printf, 1, 2)))
  1608. __simple_attr_check_format(const char *fmt, ...)
  1609. {
  1610. /* don't do anything, just let the compiler check the arguments; */
  1611. }
  1612. int simple_attr_open(struct inode *inode, struct file *file,
  1613. u64 (*get)(void *), void (*set)(void *, u64),
  1614. const char *fmt);
  1615. int simple_attr_close(struct inode *inode, struct file *file);
  1616. ssize_t simple_attr_read(struct file *file, char __user *buf,
  1617. size_t len, loff_t *ppos);
  1618. ssize_t simple_attr_write(struct file *file, const char __user *buf,
  1619. size_t len, loff_t *ppos);
  1620. #ifdef CONFIG_SECURITY
  1621. static inline char *alloc_secdata(void)
  1622. {
  1623. return (char *)get_zeroed_page(GFP_KERNEL);
  1624. }
  1625. static inline void free_secdata(void *secdata)
  1626. {
  1627. free_page((unsigned long)secdata);
  1628. }
  1629. #else
  1630. static inline char *alloc_secdata(void)
  1631. {
  1632. return (char *)1;
  1633. }
  1634. static inline void free_secdata(void *secdata)
  1635. { }
  1636. #endif /* CONFIG_SECURITY */
  1637. #endif /* __KERNEL__ */
  1638. #endif /* _LINUX_FS_H */