inode.c 43 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050105110521053105410551056105710581059106010611062106310641065106610671068106910701071107210731074107510761077107810791080108110821083108410851086108710881089109010911092109310941095109610971098109911001101110211031104110511061107110811091110111111121113111411151116111711181119112011211122112311241125112611271128112911301131113211331134113511361137113811391140114111421143114411451146114711481149115011511152115311541155115611571158115911601161116211631164116511661167116811691170117111721173117411751176117711781179118011811182118311841185118611871188118911901191119211931194119511961197119811991200120112021203120412051206120712081209121012111212121312141215121612171218121912201221122212231224122512261227122812291230123112321233123412351236123712381239124012411242124312441245124612471248124912501251125212531254125512561257125812591260126112621263126412651266126712681269127012711272127312741275127612771278127912801281128212831284128512861287128812891290129112921293129412951296129712981299130013011302130313041305130613071308130913101311131213131314131513161317131813191320132113221323132413251326132713281329133013311332133313341335133613371338133913401341134213431344134513461347134813491350135113521353135413551356135713581359136013611362136313641365136613671368136913701371137213731374137513761377137813791380138113821383138413851386138713881389139013911392139313941395139613971398139914001401140214031404140514061407140814091410141114121413141414151416141714181419142014211422142314241425142614271428142914301431143214331434143514361437143814391440144114421443144414451446144714481449145014511452145314541455145614571458145914601461146214631464146514661467146814691470147114721473147414751476147714781479148014811482148314841485148614871488148914901491149214931494149514961497149814991500150115021503150415051506150715081509151015111512151315141515151615171518151915201521152215231524152515261527152815291530153115321533153415351536153715381539154015411542154315441545154615471548154915501551155215531554155515561557155815591560156115621563156415651566156715681569157015711572157315741575157615771578157915801581158215831584158515861587158815891590159115921593159415951596159715981599160016011602160316041605160616071608160916101611161216131614161516161617161816191620162116221623162416251626162716281629163016311632163316341635163616371638163916401641164216431644164516461647164816491650165116521653165416551656
  1. /*
  2. * linux/fs/fat/inode.c
  3. *
  4. * Written 1992,1993 by Werner Almesberger
  5. * VFAT extensions by Gordon Chaffee, merged with msdos fs by Henrik Storner
  6. * Rewritten for the constant inumbers support by Al Viro
  7. *
  8. * Fixes:
  9. *
  10. * Max Cohan: Fixed invalid FSINFO offset when info_sector is 0
  11. */
  12. #include <linux/module.h>
  13. #include <linux/init.h>
  14. #include <linux/time.h>
  15. #include <linux/slab.h>
  16. #include <linux/seq_file.h>
  17. #include <linux/pagemap.h>
  18. #include <linux/mpage.h>
  19. #include <linux/buffer_head.h>
  20. #include <linux/mount.h>
  21. #include <linux/aio.h>
  22. #include <linux/vfs.h>
  23. #include <linux/parser.h>
  24. #include <linux/uio.h>
  25. #include <linux/writeback.h>
  26. #include <linux/log2.h>
  27. #include <linux/hash.h>
  28. #include <linux/blkdev.h>
  29. #include <asm/unaligned.h>
  30. #include "fat.h"
  31. #ifndef CONFIG_FAT_DEFAULT_IOCHARSET
  32. /* if user don't select VFAT, this is undefined. */
  33. #define CONFIG_FAT_DEFAULT_IOCHARSET ""
  34. #endif
  35. static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE;
  36. static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET;
  37. static int fat_add_cluster(struct inode *inode)
  38. {
  39. int err, cluster;
  40. err = fat_alloc_clusters(inode, &cluster, 1);
  41. if (err)
  42. return err;
  43. /* FIXME: this cluster should be added after data of this
  44. * cluster is writed */
  45. err = fat_chain_add(inode, cluster, 1);
  46. if (err)
  47. fat_free_clusters(inode, cluster);
  48. return err;
  49. }
  50. static inline int __fat_get_block(struct inode *inode, sector_t iblock,
  51. unsigned long *max_blocks,
  52. struct buffer_head *bh_result, int create)
  53. {
  54. struct super_block *sb = inode->i_sb;
  55. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  56. unsigned long mapped_blocks;
  57. sector_t phys;
  58. int err, offset;
  59. err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
  60. if (err)
  61. return err;
  62. if (phys) {
  63. map_bh(bh_result, sb, phys);
  64. *max_blocks = min(mapped_blocks, *max_blocks);
  65. return 0;
  66. }
  67. if (!create)
  68. return 0;
  69. if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) {
  70. fat_fs_error(sb, "corrupted file size (i_pos %lld, %lld)",
  71. MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private);
  72. return -EIO;
  73. }
  74. offset = (unsigned long)iblock & (sbi->sec_per_clus - 1);
  75. if (!offset) {
  76. /* TODO: multiple cluster allocation would be desirable. */
  77. err = fat_add_cluster(inode);
  78. if (err)
  79. return err;
  80. }
  81. /* available blocks on this cluster */
  82. mapped_blocks = sbi->sec_per_clus - offset;
  83. *max_blocks = min(mapped_blocks, *max_blocks);
  84. MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits;
  85. err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
  86. if (err)
  87. return err;
  88. BUG_ON(!phys);
  89. BUG_ON(*max_blocks != mapped_blocks);
  90. set_buffer_new(bh_result);
  91. map_bh(bh_result, sb, phys);
  92. return 0;
  93. }
  94. static int fat_get_block(struct inode *inode, sector_t iblock,
  95. struct buffer_head *bh_result, int create)
  96. {
  97. struct super_block *sb = inode->i_sb;
  98. unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
  99. int err;
  100. err = __fat_get_block(inode, iblock, &max_blocks, bh_result, create);
  101. if (err)
  102. return err;
  103. bh_result->b_size = max_blocks << sb->s_blocksize_bits;
  104. return 0;
  105. }
  106. static int fat_writepage(struct page *page, struct writeback_control *wbc)
  107. {
  108. return block_write_full_page(page, fat_get_block, wbc);
  109. }
  110. static int fat_writepages(struct address_space *mapping,
  111. struct writeback_control *wbc)
  112. {
  113. return mpage_writepages(mapping, wbc, fat_get_block);
  114. }
  115. static int fat_readpage(struct file *file, struct page *page)
  116. {
  117. return mpage_readpage(page, fat_get_block);
  118. }
  119. static int fat_readpages(struct file *file, struct address_space *mapping,
  120. struct list_head *pages, unsigned nr_pages)
  121. {
  122. return mpage_readpages(mapping, pages, nr_pages, fat_get_block);
  123. }
  124. static void fat_write_failed(struct address_space *mapping, loff_t to)
  125. {
  126. struct inode *inode = mapping->host;
  127. if (to > inode->i_size) {
  128. truncate_pagecache(inode, inode->i_size);
  129. fat_truncate_blocks(inode, inode->i_size);
  130. }
  131. }
  132. static int fat_write_begin(struct file *file, struct address_space *mapping,
  133. loff_t pos, unsigned len, unsigned flags,
  134. struct page **pagep, void **fsdata)
  135. {
  136. int err;
  137. *pagep = NULL;
  138. err = cont_write_begin(file, mapping, pos, len, flags,
  139. pagep, fsdata, fat_get_block,
  140. &MSDOS_I(mapping->host)->mmu_private);
  141. if (err < 0)
  142. fat_write_failed(mapping, pos + len);
  143. return err;
  144. }
  145. static int fat_write_end(struct file *file, struct address_space *mapping,
  146. loff_t pos, unsigned len, unsigned copied,
  147. struct page *pagep, void *fsdata)
  148. {
  149. struct inode *inode = mapping->host;
  150. int err;
  151. err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
  152. if (err < len)
  153. fat_write_failed(mapping, pos + len);
  154. if (!(err < 0) && !(MSDOS_I(inode)->i_attrs & ATTR_ARCH)) {
  155. inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
  156. MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
  157. mark_inode_dirty(inode);
  158. }
  159. return err;
  160. }
  161. static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
  162. const struct iovec *iov,
  163. loff_t offset, unsigned long nr_segs)
  164. {
  165. struct file *file = iocb->ki_filp;
  166. struct address_space *mapping = file->f_mapping;
  167. struct inode *inode = mapping->host;
  168. ssize_t ret;
  169. if (rw == WRITE) {
  170. /*
  171. * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
  172. * so we need to update the ->mmu_private to block boundary.
  173. *
  174. * But we must fill the remaining area or hole by nul for
  175. * updating ->mmu_private.
  176. *
  177. * Return 0, and fallback to normal buffered write.
  178. */
  179. loff_t size = offset + iov_length(iov, nr_segs);
  180. if (MSDOS_I(inode)->mmu_private < size)
  181. return 0;
  182. }
  183. /*
  184. * FAT need to use the DIO_LOCKING for avoiding the race
  185. * condition of fat_get_block() and ->truncate().
  186. */
  187. ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
  188. fat_get_block);
  189. if (ret < 0 && (rw & WRITE))
  190. fat_write_failed(mapping, offset + iov_length(iov, nr_segs));
  191. return ret;
  192. }
  193. static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
  194. {
  195. sector_t blocknr;
  196. /* fat_get_cluster() assumes the requested blocknr isn't truncated. */
  197. down_read(&MSDOS_I(mapping->host)->truncate_lock);
  198. blocknr = generic_block_bmap(mapping, block, fat_get_block);
  199. up_read(&MSDOS_I(mapping->host)->truncate_lock);
  200. return blocknr;
  201. }
  202. static const struct address_space_operations fat_aops = {
  203. .readpage = fat_readpage,
  204. .readpages = fat_readpages,
  205. .writepage = fat_writepage,
  206. .writepages = fat_writepages,
  207. .write_begin = fat_write_begin,
  208. .write_end = fat_write_end,
  209. .direct_IO = fat_direct_IO,
  210. .bmap = _fat_bmap
  211. };
  212. /*
  213. * New FAT inode stuff. We do the following:
  214. * a) i_ino is constant and has nothing with on-disk location.
  215. * b) FAT manages its own cache of directory entries.
  216. * c) *This* cache is indexed by on-disk location.
  217. * d) inode has an associated directory entry, all right, but
  218. * it may be unhashed.
  219. * e) currently entries are stored within struct inode. That should
  220. * change.
  221. * f) we deal with races in the following way:
  222. * 1. readdir() and lookup() do FAT-dir-cache lookup.
  223. * 2. rename() unhashes the F-d-c entry and rehashes it in
  224. * a new place.
  225. * 3. unlink() and rmdir() unhash F-d-c entry.
  226. * 4. fat_write_inode() checks whether the thing is unhashed.
  227. * If it is we silently return. If it isn't we do bread(),
  228. * check if the location is still valid and retry if it
  229. * isn't. Otherwise we do changes.
  230. * 5. Spinlock is used to protect hash/unhash/location check/lookup
  231. * 6. fat_evict_inode() unhashes the F-d-c entry.
  232. * 7. lookup() and readdir() do igrab() if they find a F-d-c entry
  233. * and consider negative result as cache miss.
  234. */
  235. static void fat_hash_init(struct super_block *sb)
  236. {
  237. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  238. int i;
  239. spin_lock_init(&sbi->inode_hash_lock);
  240. for (i = 0; i < FAT_HASH_SIZE; i++)
  241. INIT_HLIST_HEAD(&sbi->inode_hashtable[i]);
  242. }
  243. static inline unsigned long fat_hash(loff_t i_pos)
  244. {
  245. return hash_32(i_pos, FAT_HASH_BITS);
  246. }
  247. static void dir_hash_init(struct super_block *sb)
  248. {
  249. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  250. int i;
  251. spin_lock_init(&sbi->dir_hash_lock);
  252. for (i = 0; i < FAT_HASH_SIZE; i++)
  253. INIT_HLIST_HEAD(&sbi->dir_hashtable[i]);
  254. }
  255. void fat_attach(struct inode *inode, loff_t i_pos)
  256. {
  257. struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
  258. if (inode->i_ino != MSDOS_ROOT_INO) {
  259. struct hlist_head *head = sbi->inode_hashtable
  260. + fat_hash(i_pos);
  261. spin_lock(&sbi->inode_hash_lock);
  262. MSDOS_I(inode)->i_pos = i_pos;
  263. hlist_add_head(&MSDOS_I(inode)->i_fat_hash, head);
  264. spin_unlock(&sbi->inode_hash_lock);
  265. }
  266. /* If NFS support is enabled, cache the mapping of start cluster
  267. * to directory inode. This is used during reconnection of
  268. * dentries to the filesystem root.
  269. */
  270. if (S_ISDIR(inode->i_mode) && sbi->options.nfs) {
  271. struct hlist_head *d_head = sbi->dir_hashtable;
  272. d_head += fat_dir_hash(MSDOS_I(inode)->i_logstart);
  273. spin_lock(&sbi->dir_hash_lock);
  274. hlist_add_head(&MSDOS_I(inode)->i_dir_hash, d_head);
  275. spin_unlock(&sbi->dir_hash_lock);
  276. }
  277. }
  278. EXPORT_SYMBOL_GPL(fat_attach);
  279. void fat_detach(struct inode *inode)
  280. {
  281. struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
  282. spin_lock(&sbi->inode_hash_lock);
  283. MSDOS_I(inode)->i_pos = 0;
  284. hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
  285. spin_unlock(&sbi->inode_hash_lock);
  286. if (S_ISDIR(inode->i_mode) && sbi->options.nfs) {
  287. spin_lock(&sbi->dir_hash_lock);
  288. hlist_del_init(&MSDOS_I(inode)->i_dir_hash);
  289. spin_unlock(&sbi->dir_hash_lock);
  290. }
  291. }
  292. EXPORT_SYMBOL_GPL(fat_detach);
  293. struct inode *fat_iget(struct super_block *sb, loff_t i_pos)
  294. {
  295. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  296. struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos);
  297. struct msdos_inode_info *i;
  298. struct inode *inode = NULL;
  299. spin_lock(&sbi->inode_hash_lock);
  300. hlist_for_each_entry(i, head, i_fat_hash) {
  301. BUG_ON(i->vfs_inode.i_sb != sb);
  302. if (i->i_pos != i_pos)
  303. continue;
  304. inode = igrab(&i->vfs_inode);
  305. if (inode)
  306. break;
  307. }
  308. spin_unlock(&sbi->inode_hash_lock);
  309. return inode;
  310. }
  311. static int is_exec(unsigned char *extension)
  312. {
  313. unsigned char *exe_extensions = "EXECOMBAT", *walk;
  314. for (walk = exe_extensions; *walk; walk += 3)
  315. if (!strncmp(extension, walk, 3))
  316. return 1;
  317. return 0;
  318. }
  319. static int fat_calc_dir_size(struct inode *inode)
  320. {
  321. struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
  322. int ret, fclus, dclus;
  323. inode->i_size = 0;
  324. if (MSDOS_I(inode)->i_start == 0)
  325. return 0;
  326. ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
  327. if (ret < 0)
  328. return ret;
  329. inode->i_size = (fclus + 1) << sbi->cluster_bits;
  330. return 0;
  331. }
  332. /* doesn't deal with root inode */
  333. int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
  334. {
  335. struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
  336. int error;
  337. MSDOS_I(inode)->i_pos = 0;
  338. inode->i_uid = sbi->options.fs_uid;
  339. inode->i_gid = sbi->options.fs_gid;
  340. inode->i_version++;
  341. inode->i_generation = get_seconds();
  342. if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) {
  343. inode->i_generation &= ~1;
  344. inode->i_mode = fat_make_mode(sbi, de->attr, S_IRWXUGO);
  345. inode->i_op = sbi->dir_ops;
  346. inode->i_fop = &fat_dir_operations;
  347. MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
  348. MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
  349. error = fat_calc_dir_size(inode);
  350. if (error < 0)
  351. return error;
  352. MSDOS_I(inode)->mmu_private = inode->i_size;
  353. set_nlink(inode, fat_subdirs(inode));
  354. } else { /* not a directory */
  355. inode->i_generation |= 1;
  356. inode->i_mode = fat_make_mode(sbi, de->attr,
  357. ((sbi->options.showexec && !is_exec(de->name + 8))
  358. ? S_IRUGO|S_IWUGO : S_IRWXUGO));
  359. MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
  360. MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
  361. inode->i_size = le32_to_cpu(de->size);
  362. inode->i_op = &fat_file_inode_operations;
  363. inode->i_fop = &fat_file_operations;
  364. inode->i_mapping->a_ops = &fat_aops;
  365. MSDOS_I(inode)->mmu_private = inode->i_size;
  366. }
  367. if (de->attr & ATTR_SYS) {
  368. if (sbi->options.sys_immutable)
  369. inode->i_flags |= S_IMMUTABLE;
  370. }
  371. fat_save_attrs(inode, de->attr);
  372. inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
  373. & ~((loff_t)sbi->cluster_size - 1)) >> 9;
  374. fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0);
  375. if (sbi->options.isvfat) {
  376. fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime,
  377. de->cdate, de->ctime_cs);
  378. fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0);
  379. } else
  380. inode->i_ctime = inode->i_atime = inode->i_mtime;
  381. return 0;
  382. }
  383. static inline void fat_lock_build_inode(struct msdos_sb_info *sbi)
  384. {
  385. if (sbi->options.nfs == FAT_NFS_NOSTALE_RO)
  386. mutex_lock(&sbi->nfs_build_inode_lock);
  387. }
  388. static inline void fat_unlock_build_inode(struct msdos_sb_info *sbi)
  389. {
  390. if (sbi->options.nfs == FAT_NFS_NOSTALE_RO)
  391. mutex_unlock(&sbi->nfs_build_inode_lock);
  392. }
  393. struct inode *fat_build_inode(struct super_block *sb,
  394. struct msdos_dir_entry *de, loff_t i_pos)
  395. {
  396. struct inode *inode;
  397. int err;
  398. fat_lock_build_inode(MSDOS_SB(sb));
  399. inode = fat_iget(sb, i_pos);
  400. if (inode)
  401. goto out;
  402. inode = new_inode(sb);
  403. if (!inode) {
  404. inode = ERR_PTR(-ENOMEM);
  405. goto out;
  406. }
  407. inode->i_ino = iunique(sb, MSDOS_ROOT_INO);
  408. inode->i_version = 1;
  409. err = fat_fill_inode(inode, de);
  410. if (err) {
  411. iput(inode);
  412. inode = ERR_PTR(err);
  413. goto out;
  414. }
  415. fat_attach(inode, i_pos);
  416. insert_inode_hash(inode);
  417. out:
  418. fat_unlock_build_inode(MSDOS_SB(sb));
  419. return inode;
  420. }
  421. EXPORT_SYMBOL_GPL(fat_build_inode);
  422. static void fat_evict_inode(struct inode *inode)
  423. {
  424. truncate_inode_pages(&inode->i_data, 0);
  425. if (!inode->i_nlink) {
  426. inode->i_size = 0;
  427. fat_truncate_blocks(inode, 0);
  428. }
  429. invalidate_inode_buffers(inode);
  430. clear_inode(inode);
  431. fat_cache_inval_inode(inode);
  432. fat_detach(inode);
  433. }
  434. static void fat_set_state(struct super_block *sb,
  435. unsigned int set, unsigned int force)
  436. {
  437. struct buffer_head *bh;
  438. struct fat_boot_sector *b;
  439. struct msdos_sb_info *sbi = sb->s_fs_info;
  440. /* do not change any thing if mounted read only */
  441. if ((sb->s_flags & MS_RDONLY) && !force)
  442. return;
  443. /* do not change state if fs was dirty */
  444. if (sbi->dirty) {
  445. /* warn only on set (mount). */
  446. if (set)
  447. fat_msg(sb, KERN_WARNING, "Volume was not properly "
  448. "unmounted. Some data may be corrupt. "
  449. "Please run fsck.");
  450. return;
  451. }
  452. bh = sb_bread(sb, 0);
  453. if (bh == NULL) {
  454. fat_msg(sb, KERN_ERR, "unable to read boot sector "
  455. "to mark fs as dirty");
  456. return;
  457. }
  458. b = (struct fat_boot_sector *) bh->b_data;
  459. if (sbi->fat_bits == 32) {
  460. if (set)
  461. b->fat32.state |= FAT_STATE_DIRTY;
  462. else
  463. b->fat32.state &= ~FAT_STATE_DIRTY;
  464. } else /* fat 16 and 12 */ {
  465. if (set)
  466. b->fat16.state |= FAT_STATE_DIRTY;
  467. else
  468. b->fat16.state &= ~FAT_STATE_DIRTY;
  469. }
  470. mark_buffer_dirty(bh);
  471. sync_dirty_buffer(bh);
  472. brelse(bh);
  473. }
  474. static void delayed_free(struct rcu_head *p)
  475. {
  476. struct msdos_sb_info *sbi = container_of(p, struct msdos_sb_info, rcu);
  477. unload_nls(sbi->nls_disk);
  478. unload_nls(sbi->nls_io);
  479. if (sbi->options.iocharset != fat_default_iocharset)
  480. kfree(sbi->options.iocharset);
  481. kfree(sbi);
  482. }
  483. static void fat_put_super(struct super_block *sb)
  484. {
  485. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  486. fat_set_state(sb, 0, 0);
  487. iput(sbi->fsinfo_inode);
  488. iput(sbi->fat_inode);
  489. call_rcu(&sbi->rcu, delayed_free);
  490. }
  491. static struct kmem_cache *fat_inode_cachep;
  492. static struct inode *fat_alloc_inode(struct super_block *sb)
  493. {
  494. struct msdos_inode_info *ei;
  495. ei = kmem_cache_alloc(fat_inode_cachep, GFP_NOFS);
  496. if (!ei)
  497. return NULL;
  498. init_rwsem(&ei->truncate_lock);
  499. return &ei->vfs_inode;
  500. }
  501. static void fat_i_callback(struct rcu_head *head)
  502. {
  503. struct inode *inode = container_of(head, struct inode, i_rcu);
  504. kmem_cache_free(fat_inode_cachep, MSDOS_I(inode));
  505. }
  506. static void fat_destroy_inode(struct inode *inode)
  507. {
  508. call_rcu(&inode->i_rcu, fat_i_callback);
  509. }
  510. static void init_once(void *foo)
  511. {
  512. struct msdos_inode_info *ei = (struct msdos_inode_info *)foo;
  513. spin_lock_init(&ei->cache_lru_lock);
  514. ei->nr_caches = 0;
  515. ei->cache_valid_id = FAT_CACHE_VALID + 1;
  516. INIT_LIST_HEAD(&ei->cache_lru);
  517. INIT_HLIST_NODE(&ei->i_fat_hash);
  518. INIT_HLIST_NODE(&ei->i_dir_hash);
  519. inode_init_once(&ei->vfs_inode);
  520. }
  521. static int __init fat_init_inodecache(void)
  522. {
  523. fat_inode_cachep = kmem_cache_create("fat_inode_cache",
  524. sizeof(struct msdos_inode_info),
  525. 0, (SLAB_RECLAIM_ACCOUNT|
  526. SLAB_MEM_SPREAD),
  527. init_once);
  528. if (fat_inode_cachep == NULL)
  529. return -ENOMEM;
  530. return 0;
  531. }
  532. static void __exit fat_destroy_inodecache(void)
  533. {
  534. /*
  535. * Make sure all delayed rcu free inodes are flushed before we
  536. * destroy cache.
  537. */
  538. rcu_barrier();
  539. kmem_cache_destroy(fat_inode_cachep);
  540. }
  541. static int fat_remount(struct super_block *sb, int *flags, char *data)
  542. {
  543. int new_rdonly;
  544. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  545. *flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);
  546. /* make sure we update state on remount. */
  547. new_rdonly = *flags & MS_RDONLY;
  548. if (new_rdonly != (sb->s_flags & MS_RDONLY)) {
  549. if (new_rdonly)
  550. fat_set_state(sb, 0, 0);
  551. else
  552. fat_set_state(sb, 1, 1);
  553. }
  554. return 0;
  555. }
  556. static int fat_statfs(struct dentry *dentry, struct kstatfs *buf)
  557. {
  558. struct super_block *sb = dentry->d_sb;
  559. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  560. u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
  561. /* If the count of free cluster is still unknown, counts it here. */
  562. if (sbi->free_clusters == -1 || !sbi->free_clus_valid) {
  563. int err = fat_count_free_clusters(dentry->d_sb);
  564. if (err)
  565. return err;
  566. }
  567. buf->f_type = dentry->d_sb->s_magic;
  568. buf->f_bsize = sbi->cluster_size;
  569. buf->f_blocks = sbi->max_cluster - FAT_START_ENT;
  570. buf->f_bfree = sbi->free_clusters;
  571. buf->f_bavail = sbi->free_clusters;
  572. buf->f_fsid.val[0] = (u32)id;
  573. buf->f_fsid.val[1] = (u32)(id >> 32);
  574. buf->f_namelen =
  575. (sbi->options.isvfat ? FAT_LFN_LEN : 12) * NLS_MAX_CHARSET_SIZE;
  576. return 0;
  577. }
  578. static int __fat_write_inode(struct inode *inode, int wait)
  579. {
  580. struct super_block *sb = inode->i_sb;
  581. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  582. struct buffer_head *bh;
  583. struct msdos_dir_entry *raw_entry;
  584. loff_t i_pos;
  585. sector_t blocknr;
  586. int err, offset;
  587. if (inode->i_ino == MSDOS_ROOT_INO)
  588. return 0;
  589. retry:
  590. i_pos = fat_i_pos_read(sbi, inode);
  591. if (!i_pos)
  592. return 0;
  593. fat_get_blknr_offset(sbi, i_pos, &blocknr, &offset);
  594. bh = sb_bread(sb, blocknr);
  595. if (!bh) {
  596. fat_msg(sb, KERN_ERR, "unable to read inode block "
  597. "for updating (i_pos %lld)", i_pos);
  598. return -EIO;
  599. }
  600. spin_lock(&sbi->inode_hash_lock);
  601. if (i_pos != MSDOS_I(inode)->i_pos) {
  602. spin_unlock(&sbi->inode_hash_lock);
  603. brelse(bh);
  604. goto retry;
  605. }
  606. raw_entry = &((struct msdos_dir_entry *) (bh->b_data))[offset];
  607. if (S_ISDIR(inode->i_mode))
  608. raw_entry->size = 0;
  609. else
  610. raw_entry->size = cpu_to_le32(inode->i_size);
  611. raw_entry->attr = fat_make_attrs(inode);
  612. fat_set_start(raw_entry, MSDOS_I(inode)->i_logstart);
  613. fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
  614. &raw_entry->date, NULL);
  615. if (sbi->options.isvfat) {
  616. __le16 atime;
  617. fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime,
  618. &raw_entry->cdate, &raw_entry->ctime_cs);
  619. fat_time_unix2fat(sbi, &inode->i_atime, &atime,
  620. &raw_entry->adate, NULL);
  621. }
  622. spin_unlock(&sbi->inode_hash_lock);
  623. mark_buffer_dirty(bh);
  624. err = 0;
  625. if (wait)
  626. err = sync_dirty_buffer(bh);
  627. brelse(bh);
  628. return err;
  629. }
  630. static int fat_write_inode(struct inode *inode, struct writeback_control *wbc)
  631. {
  632. int err;
  633. if (inode->i_ino == MSDOS_FSINFO_INO) {
  634. struct super_block *sb = inode->i_sb;
  635. mutex_lock(&MSDOS_SB(sb)->s_lock);
  636. err = fat_clusters_flush(sb);
  637. mutex_unlock(&MSDOS_SB(sb)->s_lock);
  638. } else
  639. err = __fat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
  640. return err;
  641. }
  642. int fat_sync_inode(struct inode *inode)
  643. {
  644. return __fat_write_inode(inode, 1);
  645. }
  646. EXPORT_SYMBOL_GPL(fat_sync_inode);
  647. static int fat_show_options(struct seq_file *m, struct dentry *root);
  648. static const struct super_operations fat_sops = {
  649. .alloc_inode = fat_alloc_inode,
  650. .destroy_inode = fat_destroy_inode,
  651. .write_inode = fat_write_inode,
  652. .evict_inode = fat_evict_inode,
  653. .put_super = fat_put_super,
  654. .statfs = fat_statfs,
  655. .remount_fs = fat_remount,
  656. .show_options = fat_show_options,
  657. };
  658. static int fat_show_options(struct seq_file *m, struct dentry *root)
  659. {
  660. struct msdos_sb_info *sbi = MSDOS_SB(root->d_sb);
  661. struct fat_mount_options *opts = &sbi->options;
  662. int isvfat = opts->isvfat;
  663. if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID))
  664. seq_printf(m, ",uid=%u",
  665. from_kuid_munged(&init_user_ns, opts->fs_uid));
  666. if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID))
  667. seq_printf(m, ",gid=%u",
  668. from_kgid_munged(&init_user_ns, opts->fs_gid));
  669. seq_printf(m, ",fmask=%04o", opts->fs_fmask);
  670. seq_printf(m, ",dmask=%04o", opts->fs_dmask);
  671. if (opts->allow_utime)
  672. seq_printf(m, ",allow_utime=%04o", opts->allow_utime);
  673. if (sbi->nls_disk)
  674. /* strip "cp" prefix from displayed option */
  675. seq_printf(m, ",codepage=%s", &sbi->nls_disk->charset[2]);
  676. if (isvfat) {
  677. if (sbi->nls_io)
  678. seq_printf(m, ",iocharset=%s", sbi->nls_io->charset);
  679. switch (opts->shortname) {
  680. case VFAT_SFN_DISPLAY_WIN95 | VFAT_SFN_CREATE_WIN95:
  681. seq_puts(m, ",shortname=win95");
  682. break;
  683. case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WINNT:
  684. seq_puts(m, ",shortname=winnt");
  685. break;
  686. case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WIN95:
  687. seq_puts(m, ",shortname=mixed");
  688. break;
  689. case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95:
  690. seq_puts(m, ",shortname=lower");
  691. break;
  692. default:
  693. seq_puts(m, ",shortname=unknown");
  694. break;
  695. }
  696. }
  697. if (opts->name_check != 'n')
  698. seq_printf(m, ",check=%c", opts->name_check);
  699. if (opts->usefree)
  700. seq_puts(m, ",usefree");
  701. if (opts->quiet)
  702. seq_puts(m, ",quiet");
  703. if (opts->showexec)
  704. seq_puts(m, ",showexec");
  705. if (opts->sys_immutable)
  706. seq_puts(m, ",sys_immutable");
  707. if (!isvfat) {
  708. if (opts->dotsOK)
  709. seq_puts(m, ",dotsOK=yes");
  710. if (opts->nocase)
  711. seq_puts(m, ",nocase");
  712. } else {
  713. if (opts->utf8)
  714. seq_puts(m, ",utf8");
  715. if (opts->unicode_xlate)
  716. seq_puts(m, ",uni_xlate");
  717. if (!opts->numtail)
  718. seq_puts(m, ",nonumtail");
  719. if (opts->rodir)
  720. seq_puts(m, ",rodir");
  721. }
  722. if (opts->flush)
  723. seq_puts(m, ",flush");
  724. if (opts->tz_set) {
  725. if (opts->time_offset)
  726. seq_printf(m, ",time_offset=%d", opts->time_offset);
  727. else
  728. seq_puts(m, ",tz=UTC");
  729. }
  730. if (opts->errors == FAT_ERRORS_CONT)
  731. seq_puts(m, ",errors=continue");
  732. else if (opts->errors == FAT_ERRORS_PANIC)
  733. seq_puts(m, ",errors=panic");
  734. else
  735. seq_puts(m, ",errors=remount-ro");
  736. if (opts->nfs == FAT_NFS_NOSTALE_RO)
  737. seq_puts(m, ",nfs=nostale_ro");
  738. else if (opts->nfs)
  739. seq_puts(m, ",nfs=stale_rw");
  740. if (opts->discard)
  741. seq_puts(m, ",discard");
  742. return 0;
  743. }
  744. enum {
  745. Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid,
  746. Opt_umask, Opt_dmask, Opt_fmask, Opt_allow_utime, Opt_codepage,
  747. Opt_usefree, Opt_nocase, Opt_quiet, Opt_showexec, Opt_debug,
  748. Opt_immutable, Opt_dots, Opt_nodots,
  749. Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
  750. Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
  751. Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
  752. Opt_obsolete, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err_cont,
  753. Opt_err_panic, Opt_err_ro, Opt_discard, Opt_nfs, Opt_time_offset,
  754. Opt_nfs_stale_rw, Opt_nfs_nostale_ro, Opt_err,
  755. };
  756. static const match_table_t fat_tokens = {
  757. {Opt_check_r, "check=relaxed"},
  758. {Opt_check_s, "check=strict"},
  759. {Opt_check_n, "check=normal"},
  760. {Opt_check_r, "check=r"},
  761. {Opt_check_s, "check=s"},
  762. {Opt_check_n, "check=n"},
  763. {Opt_uid, "uid=%u"},
  764. {Opt_gid, "gid=%u"},
  765. {Opt_umask, "umask=%o"},
  766. {Opt_dmask, "dmask=%o"},
  767. {Opt_fmask, "fmask=%o"},
  768. {Opt_allow_utime, "allow_utime=%o"},
  769. {Opt_codepage, "codepage=%u"},
  770. {Opt_usefree, "usefree"},
  771. {Opt_nocase, "nocase"},
  772. {Opt_quiet, "quiet"},
  773. {Opt_showexec, "showexec"},
  774. {Opt_debug, "debug"},
  775. {Opt_immutable, "sys_immutable"},
  776. {Opt_flush, "flush"},
  777. {Opt_tz_utc, "tz=UTC"},
  778. {Opt_time_offset, "time_offset=%d"},
  779. {Opt_err_cont, "errors=continue"},
  780. {Opt_err_panic, "errors=panic"},
  781. {Opt_err_ro, "errors=remount-ro"},
  782. {Opt_discard, "discard"},
  783. {Opt_nfs_stale_rw, "nfs"},
  784. {Opt_nfs_stale_rw, "nfs=stale_rw"},
  785. {Opt_nfs_nostale_ro, "nfs=nostale_ro"},
  786. {Opt_obsolete, "conv=binary"},
  787. {Opt_obsolete, "conv=text"},
  788. {Opt_obsolete, "conv=auto"},
  789. {Opt_obsolete, "conv=b"},
  790. {Opt_obsolete, "conv=t"},
  791. {Opt_obsolete, "conv=a"},
  792. {Opt_obsolete, "fat=%u"},
  793. {Opt_obsolete, "blocksize=%u"},
  794. {Opt_obsolete, "cvf_format=%20s"},
  795. {Opt_obsolete, "cvf_options=%100s"},
  796. {Opt_obsolete, "posix"},
  797. {Opt_err, NULL},
  798. };
  799. static const match_table_t msdos_tokens = {
  800. {Opt_nodots, "nodots"},
  801. {Opt_nodots, "dotsOK=no"},
  802. {Opt_dots, "dots"},
  803. {Opt_dots, "dotsOK=yes"},
  804. {Opt_err, NULL}
  805. };
  806. static const match_table_t vfat_tokens = {
  807. {Opt_charset, "iocharset=%s"},
  808. {Opt_shortname_lower, "shortname=lower"},
  809. {Opt_shortname_win95, "shortname=win95"},
  810. {Opt_shortname_winnt, "shortname=winnt"},
  811. {Opt_shortname_mixed, "shortname=mixed"},
  812. {Opt_utf8_no, "utf8=0"}, /* 0 or no or false */
  813. {Opt_utf8_no, "utf8=no"},
  814. {Opt_utf8_no, "utf8=false"},
  815. {Opt_utf8_yes, "utf8=1"}, /* empty or 1 or yes or true */
  816. {Opt_utf8_yes, "utf8=yes"},
  817. {Opt_utf8_yes, "utf8=true"},
  818. {Opt_utf8_yes, "utf8"},
  819. {Opt_uni_xl_no, "uni_xlate=0"}, /* 0 or no or false */
  820. {Opt_uni_xl_no, "uni_xlate=no"},
  821. {Opt_uni_xl_no, "uni_xlate=false"},
  822. {Opt_uni_xl_yes, "uni_xlate=1"}, /* empty or 1 or yes or true */
  823. {Opt_uni_xl_yes, "uni_xlate=yes"},
  824. {Opt_uni_xl_yes, "uni_xlate=true"},
  825. {Opt_uni_xl_yes, "uni_xlate"},
  826. {Opt_nonumtail_no, "nonumtail=0"}, /* 0 or no or false */
  827. {Opt_nonumtail_no, "nonumtail=no"},
  828. {Opt_nonumtail_no, "nonumtail=false"},
  829. {Opt_nonumtail_yes, "nonumtail=1"}, /* empty or 1 or yes or true */
  830. {Opt_nonumtail_yes, "nonumtail=yes"},
  831. {Opt_nonumtail_yes, "nonumtail=true"},
  832. {Opt_nonumtail_yes, "nonumtail"},
  833. {Opt_rodir, "rodir"},
  834. {Opt_err, NULL}
  835. };
  836. static int parse_options(struct super_block *sb, char *options, int is_vfat,
  837. int silent, int *debug, struct fat_mount_options *opts)
  838. {
  839. char *p;
  840. substring_t args[MAX_OPT_ARGS];
  841. int option;
  842. char *iocharset;
  843. opts->isvfat = is_vfat;
  844. opts->fs_uid = current_uid();
  845. opts->fs_gid = current_gid();
  846. opts->fs_fmask = opts->fs_dmask = current_umask();
  847. opts->allow_utime = -1;
  848. opts->codepage = fat_default_codepage;
  849. opts->iocharset = fat_default_iocharset;
  850. if (is_vfat) {
  851. opts->shortname = VFAT_SFN_DISPLAY_WINNT|VFAT_SFN_CREATE_WIN95;
  852. opts->rodir = 0;
  853. } else {
  854. opts->shortname = 0;
  855. opts->rodir = 1;
  856. }
  857. opts->name_check = 'n';
  858. opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0;
  859. opts->utf8 = opts->unicode_xlate = 0;
  860. opts->numtail = 1;
  861. opts->usefree = opts->nocase = 0;
  862. opts->tz_set = 0;
  863. opts->nfs = 0;
  864. opts->errors = FAT_ERRORS_RO;
  865. *debug = 0;
  866. if (!options)
  867. goto out;
  868. while ((p = strsep(&options, ",")) != NULL) {
  869. int token;
  870. if (!*p)
  871. continue;
  872. token = match_token(p, fat_tokens, args);
  873. if (token == Opt_err) {
  874. if (is_vfat)
  875. token = match_token(p, vfat_tokens, args);
  876. else
  877. token = match_token(p, msdos_tokens, args);
  878. }
  879. switch (token) {
  880. case Opt_check_s:
  881. opts->name_check = 's';
  882. break;
  883. case Opt_check_r:
  884. opts->name_check = 'r';
  885. break;
  886. case Opt_check_n:
  887. opts->name_check = 'n';
  888. break;
  889. case Opt_usefree:
  890. opts->usefree = 1;
  891. break;
  892. case Opt_nocase:
  893. if (!is_vfat)
  894. opts->nocase = 1;
  895. else {
  896. /* for backward compatibility */
  897. opts->shortname = VFAT_SFN_DISPLAY_WIN95
  898. | VFAT_SFN_CREATE_WIN95;
  899. }
  900. break;
  901. case Opt_quiet:
  902. opts->quiet = 1;
  903. break;
  904. case Opt_showexec:
  905. opts->showexec = 1;
  906. break;
  907. case Opt_debug:
  908. *debug = 1;
  909. break;
  910. case Opt_immutable:
  911. opts->sys_immutable = 1;
  912. break;
  913. case Opt_uid:
  914. if (match_int(&args[0], &option))
  915. return -EINVAL;
  916. opts->fs_uid = make_kuid(current_user_ns(), option);
  917. if (!uid_valid(opts->fs_uid))
  918. return -EINVAL;
  919. break;
  920. case Opt_gid:
  921. if (match_int(&args[0], &option))
  922. return -EINVAL;
  923. opts->fs_gid = make_kgid(current_user_ns(), option);
  924. if (!gid_valid(opts->fs_gid))
  925. return -EINVAL;
  926. break;
  927. case Opt_umask:
  928. if (match_octal(&args[0], &option))
  929. return -EINVAL;
  930. opts->fs_fmask = opts->fs_dmask = option;
  931. break;
  932. case Opt_dmask:
  933. if (match_octal(&args[0], &option))
  934. return -EINVAL;
  935. opts->fs_dmask = option;
  936. break;
  937. case Opt_fmask:
  938. if (match_octal(&args[0], &option))
  939. return -EINVAL;
  940. opts->fs_fmask = option;
  941. break;
  942. case Opt_allow_utime:
  943. if (match_octal(&args[0], &option))
  944. return -EINVAL;
  945. opts->allow_utime = option & (S_IWGRP | S_IWOTH);
  946. break;
  947. case Opt_codepage:
  948. if (match_int(&args[0], &option))
  949. return -EINVAL;
  950. opts->codepage = option;
  951. break;
  952. case Opt_flush:
  953. opts->flush = 1;
  954. break;
  955. case Opt_time_offset:
  956. if (match_int(&args[0], &option))
  957. return -EINVAL;
  958. if (option < -12 * 60 || option > 12 * 60)
  959. return -EINVAL;
  960. opts->tz_set = 1;
  961. opts->time_offset = option;
  962. break;
  963. case Opt_tz_utc:
  964. opts->tz_set = 1;
  965. opts->time_offset = 0;
  966. break;
  967. case Opt_err_cont:
  968. opts->errors = FAT_ERRORS_CONT;
  969. break;
  970. case Opt_err_panic:
  971. opts->errors = FAT_ERRORS_PANIC;
  972. break;
  973. case Opt_err_ro:
  974. opts->errors = FAT_ERRORS_RO;
  975. break;
  976. case Opt_nfs_stale_rw:
  977. opts->nfs = FAT_NFS_STALE_RW;
  978. break;
  979. case Opt_nfs_nostale_ro:
  980. opts->nfs = FAT_NFS_NOSTALE_RO;
  981. break;
  982. /* msdos specific */
  983. case Opt_dots:
  984. opts->dotsOK = 1;
  985. break;
  986. case Opt_nodots:
  987. opts->dotsOK = 0;
  988. break;
  989. /* vfat specific */
  990. case Opt_charset:
  991. if (opts->iocharset != fat_default_iocharset)
  992. kfree(opts->iocharset);
  993. iocharset = match_strdup(&args[0]);
  994. if (!iocharset)
  995. return -ENOMEM;
  996. opts->iocharset = iocharset;
  997. break;
  998. case Opt_shortname_lower:
  999. opts->shortname = VFAT_SFN_DISPLAY_LOWER
  1000. | VFAT_SFN_CREATE_WIN95;
  1001. break;
  1002. case Opt_shortname_win95:
  1003. opts->shortname = VFAT_SFN_DISPLAY_WIN95
  1004. | VFAT_SFN_CREATE_WIN95;
  1005. break;
  1006. case Opt_shortname_winnt:
  1007. opts->shortname = VFAT_SFN_DISPLAY_WINNT
  1008. | VFAT_SFN_CREATE_WINNT;
  1009. break;
  1010. case Opt_shortname_mixed:
  1011. opts->shortname = VFAT_SFN_DISPLAY_WINNT
  1012. | VFAT_SFN_CREATE_WIN95;
  1013. break;
  1014. case Opt_utf8_no: /* 0 or no or false */
  1015. opts->utf8 = 0;
  1016. break;
  1017. case Opt_utf8_yes: /* empty or 1 or yes or true */
  1018. opts->utf8 = 1;
  1019. break;
  1020. case Opt_uni_xl_no: /* 0 or no or false */
  1021. opts->unicode_xlate = 0;
  1022. break;
  1023. case Opt_uni_xl_yes: /* empty or 1 or yes or true */
  1024. opts->unicode_xlate = 1;
  1025. break;
  1026. case Opt_nonumtail_no: /* 0 or no or false */
  1027. opts->numtail = 1; /* negated option */
  1028. break;
  1029. case Opt_nonumtail_yes: /* empty or 1 or yes or true */
  1030. opts->numtail = 0; /* negated option */
  1031. break;
  1032. case Opt_rodir:
  1033. opts->rodir = 1;
  1034. break;
  1035. case Opt_discard:
  1036. opts->discard = 1;
  1037. break;
  1038. /* obsolete mount options */
  1039. case Opt_obsolete:
  1040. fat_msg(sb, KERN_INFO, "\"%s\" option is obsolete, "
  1041. "not supported now", p);
  1042. break;
  1043. /* unknown option */
  1044. default:
  1045. if (!silent) {
  1046. fat_msg(sb, KERN_ERR,
  1047. "Unrecognized mount option \"%s\" "
  1048. "or missing value", p);
  1049. }
  1050. return -EINVAL;
  1051. }
  1052. }
  1053. out:
  1054. /* UTF-8 doesn't provide FAT semantics */
  1055. if (!strcmp(opts->iocharset, "utf8")) {
  1056. fat_msg(sb, KERN_WARNING, "utf8 is not a recommended IO charset"
  1057. " for FAT filesystems, filesystem will be "
  1058. "case sensitive!");
  1059. }
  1060. /* If user doesn't specify allow_utime, it's initialized from dmask. */
  1061. if (opts->allow_utime == (unsigned short)-1)
  1062. opts->allow_utime = ~opts->fs_dmask & (S_IWGRP | S_IWOTH);
  1063. if (opts->unicode_xlate)
  1064. opts->utf8 = 0;
  1065. if (opts->nfs == FAT_NFS_NOSTALE_RO) {
  1066. sb->s_flags |= MS_RDONLY;
  1067. sb->s_export_op = &fat_export_ops_nostale;
  1068. }
  1069. return 0;
  1070. }
  1071. static int fat_read_root(struct inode *inode)
  1072. {
  1073. struct super_block *sb = inode->i_sb;
  1074. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  1075. int error;
  1076. MSDOS_I(inode)->i_pos = MSDOS_ROOT_INO;
  1077. inode->i_uid = sbi->options.fs_uid;
  1078. inode->i_gid = sbi->options.fs_gid;
  1079. inode->i_version++;
  1080. inode->i_generation = 0;
  1081. inode->i_mode = fat_make_mode(sbi, ATTR_DIR, S_IRWXUGO);
  1082. inode->i_op = sbi->dir_ops;
  1083. inode->i_fop = &fat_dir_operations;
  1084. if (sbi->fat_bits == 32) {
  1085. MSDOS_I(inode)->i_start = sbi->root_cluster;
  1086. error = fat_calc_dir_size(inode);
  1087. if (error < 0)
  1088. return error;
  1089. } else {
  1090. MSDOS_I(inode)->i_start = 0;
  1091. inode->i_size = sbi->dir_entries * sizeof(struct msdos_dir_entry);
  1092. }
  1093. inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
  1094. & ~((loff_t)sbi->cluster_size - 1)) >> 9;
  1095. MSDOS_I(inode)->i_logstart = 0;
  1096. MSDOS_I(inode)->mmu_private = inode->i_size;
  1097. fat_save_attrs(inode, ATTR_DIR);
  1098. inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0;
  1099. inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0;
  1100. set_nlink(inode, fat_subdirs(inode)+2);
  1101. return 0;
  1102. }
  1103. static unsigned long calc_fat_clusters(struct super_block *sb)
  1104. {
  1105. struct msdos_sb_info *sbi = MSDOS_SB(sb);
  1106. /* Divide first to avoid overflow */
  1107. if (sbi->fat_bits != 12) {
  1108. unsigned long ent_per_sec = sb->s_blocksize * 8 / sbi->fat_bits;
  1109. return ent_per_sec * sbi->fat_length;
  1110. }
  1111. return sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits;
  1112. }
  1113. /*
  1114. * Read the super block of an MS-DOS FS.
  1115. */
  1116. int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,
  1117. void (*setup)(struct super_block *))
  1118. {
  1119. struct inode *root_inode = NULL, *fat_inode = NULL;
  1120. struct inode *fsinfo_inode = NULL;
  1121. struct buffer_head *bh;
  1122. struct fat_boot_sector *b;
  1123. struct msdos_sb_info *sbi;
  1124. u16 logical_sector_size;
  1125. u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors;
  1126. int debug;
  1127. unsigned int media;
  1128. long error;
  1129. char buf[50];
  1130. /*
  1131. * GFP_KERNEL is ok here, because while we do hold the
  1132. * supeblock lock, memory pressure can't call back into
  1133. * the filesystem, since we're only just about to mount
  1134. * it and have no inodes etc active!
  1135. */
  1136. sbi = kzalloc(sizeof(struct msdos_sb_info), GFP_KERNEL);
  1137. if (!sbi)
  1138. return -ENOMEM;
  1139. sb->s_fs_info = sbi;
  1140. sb->s_flags |= MS_NODIRATIME;
  1141. sb->s_magic = MSDOS_SUPER_MAGIC;
  1142. sb->s_op = &fat_sops;
  1143. sb->s_export_op = &fat_export_ops;
  1144. mutex_init(&sbi->nfs_build_inode_lock);
  1145. ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL,
  1146. DEFAULT_RATELIMIT_BURST);
  1147. error = parse_options(sb, data, isvfat, silent, &debug, &sbi->options);
  1148. if (error)
  1149. goto out_fail;
  1150. setup(sb); /* flavour-specific stuff that needs options */
  1151. error = -EIO;
  1152. sb_min_blocksize(sb, 512);
  1153. bh = sb_bread(sb, 0);
  1154. if (bh == NULL) {
  1155. fat_msg(sb, KERN_ERR, "unable to read boot sector");
  1156. goto out_fail;
  1157. }
  1158. b = (struct fat_boot_sector *) bh->b_data;
  1159. if (!b->reserved) {
  1160. if (!silent)
  1161. fat_msg(sb, KERN_ERR, "bogus number of reserved sectors");
  1162. brelse(bh);
  1163. goto out_invalid;
  1164. }
  1165. if (!b->fats) {
  1166. if (!silent)
  1167. fat_msg(sb, KERN_ERR, "bogus number of FAT structure");
  1168. brelse(bh);
  1169. goto out_invalid;
  1170. }
  1171. /*
  1172. * Earlier we checked here that b->secs_track and b->head are nonzero,
  1173. * but it turns out valid FAT filesystems can have zero there.
  1174. */
  1175. media = b->media;
  1176. if (!fat_valid_media(media)) {
  1177. if (!silent)
  1178. fat_msg(sb, KERN_ERR, "invalid media value (0x%02x)",
  1179. media);
  1180. brelse(bh);
  1181. goto out_invalid;
  1182. }
  1183. logical_sector_size = get_unaligned_le16(&b->sector_size);
  1184. if (!is_power_of_2(logical_sector_size)
  1185. || (logical_sector_size < 512)
  1186. || (logical_sector_size > 4096)) {
  1187. if (!silent)
  1188. fat_msg(sb, KERN_ERR, "bogus logical sector size %u",
  1189. logical_sector_size);
  1190. brelse(bh);
  1191. goto out_invalid;
  1192. }
  1193. sbi->sec_per_clus = b->sec_per_clus;
  1194. if (!is_power_of_2(sbi->sec_per_clus)) {
  1195. if (!silent)
  1196. fat_msg(sb, KERN_ERR, "bogus sectors per cluster %u",
  1197. sbi->sec_per_clus);
  1198. brelse(bh);
  1199. goto out_invalid;
  1200. }
  1201. if (logical_sector_size < sb->s_blocksize) {
  1202. fat_msg(sb, KERN_ERR, "logical sector size too small for device"
  1203. " (logical sector size = %u)", logical_sector_size);
  1204. brelse(bh);
  1205. goto out_fail;
  1206. }
  1207. if (logical_sector_size > sb->s_blocksize) {
  1208. brelse(bh);
  1209. if (!sb_set_blocksize(sb, logical_sector_size)) {
  1210. fat_msg(sb, KERN_ERR, "unable to set blocksize %u",
  1211. logical_sector_size);
  1212. goto out_fail;
  1213. }
  1214. bh = sb_bread(sb, 0);
  1215. if (bh == NULL) {
  1216. fat_msg(sb, KERN_ERR, "unable to read boot sector"
  1217. " (logical sector size = %lu)",
  1218. sb->s_blocksize);
  1219. goto out_fail;
  1220. }
  1221. b = (struct fat_boot_sector *) bh->b_data;
  1222. }
  1223. mutex_init(&sbi->s_lock);
  1224. sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus;
  1225. sbi->cluster_bits = ffs(sbi->cluster_size) - 1;
  1226. sbi->fats = b->fats;
  1227. sbi->fat_bits = 0; /* Don't know yet */
  1228. sbi->fat_start = le16_to_cpu(b->reserved);
  1229. sbi->fat_length = le16_to_cpu(b->fat_length);
  1230. sbi->root_cluster = 0;
  1231. sbi->free_clusters = -1; /* Don't know yet */
  1232. sbi->free_clus_valid = 0;
  1233. sbi->prev_free = FAT_START_ENT;
  1234. sb->s_maxbytes = 0xffffffff;
  1235. if (!sbi->fat_length && b->fat32.length) {
  1236. struct fat_boot_fsinfo *fsinfo;
  1237. struct buffer_head *fsinfo_bh;
  1238. /* Must be FAT32 */
  1239. sbi->fat_bits = 32;
  1240. sbi->fat_length = le32_to_cpu(b->fat32.length);
  1241. sbi->root_cluster = le32_to_cpu(b->fat32.root_cluster);
  1242. /* MC - if info_sector is 0, don't multiply by 0 */
  1243. sbi->fsinfo_sector = le16_to_cpu(b->fat32.info_sector);
  1244. if (sbi->fsinfo_sector == 0)
  1245. sbi->fsinfo_sector = 1;
  1246. fsinfo_bh = sb_bread(sb, sbi->fsinfo_sector);
  1247. if (fsinfo_bh == NULL) {
  1248. fat_msg(sb, KERN_ERR, "bread failed, FSINFO block"
  1249. " (sector = %lu)", sbi->fsinfo_sector);
  1250. brelse(bh);
  1251. goto out_fail;
  1252. }
  1253. fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data;
  1254. if (!IS_FSINFO(fsinfo)) {
  1255. fat_msg(sb, KERN_WARNING, "Invalid FSINFO signature: "
  1256. "0x%08x, 0x%08x (sector = %lu)",
  1257. le32_to_cpu(fsinfo->signature1),
  1258. le32_to_cpu(fsinfo->signature2),
  1259. sbi->fsinfo_sector);
  1260. } else {
  1261. if (sbi->options.usefree)
  1262. sbi->free_clus_valid = 1;
  1263. sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters);
  1264. sbi->prev_free = le32_to_cpu(fsinfo->next_cluster);
  1265. }
  1266. brelse(fsinfo_bh);
  1267. }
  1268. /* interpret volume ID as a little endian 32 bit integer */
  1269. if (sbi->fat_bits == 32)
  1270. sbi->vol_id = (((u32)b->fat32.vol_id[0]) |
  1271. ((u32)b->fat32.vol_id[1] << 8) |
  1272. ((u32)b->fat32.vol_id[2] << 16) |
  1273. ((u32)b->fat32.vol_id[3] << 24));
  1274. else /* fat 16 or 12 */
  1275. sbi->vol_id = (((u32)b->fat16.vol_id[0]) |
  1276. ((u32)b->fat16.vol_id[1] << 8) |
  1277. ((u32)b->fat16.vol_id[2] << 16) |
  1278. ((u32)b->fat16.vol_id[3] << 24));
  1279. sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry);
  1280. sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1;
  1281. sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length;
  1282. sbi->dir_entries = get_unaligned_le16(&b->dir_entries);
  1283. if (sbi->dir_entries & (sbi->dir_per_block - 1)) {
  1284. if (!silent)
  1285. fat_msg(sb, KERN_ERR, "bogus directory-entries per block"
  1286. " (%u)", sbi->dir_entries);
  1287. brelse(bh);
  1288. goto out_invalid;
  1289. }
  1290. rootdir_sectors = sbi->dir_entries
  1291. * sizeof(struct msdos_dir_entry) / sb->s_blocksize;
  1292. sbi->data_start = sbi->dir_start + rootdir_sectors;
  1293. total_sectors = get_unaligned_le16(&b->sectors);
  1294. if (total_sectors == 0)
  1295. total_sectors = le32_to_cpu(b->total_sect);
  1296. total_clusters = (total_sectors - sbi->data_start) / sbi->sec_per_clus;
  1297. if (sbi->fat_bits != 32)
  1298. sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12;
  1299. /* some OSes set FAT_STATE_DIRTY and clean it on unmount. */
  1300. if (sbi->fat_bits == 32)
  1301. sbi->dirty = b->fat32.state & FAT_STATE_DIRTY;
  1302. else /* fat 16 or 12 */
  1303. sbi->dirty = b->fat16.state & FAT_STATE_DIRTY;
  1304. /* check that FAT table does not overflow */
  1305. fat_clusters = calc_fat_clusters(sb);
  1306. total_clusters = min(total_clusters, fat_clusters - FAT_START_ENT);
  1307. if (total_clusters > MAX_FAT(sb)) {
  1308. if (!silent)
  1309. fat_msg(sb, KERN_ERR, "count of clusters too big (%u)",
  1310. total_clusters);
  1311. brelse(bh);
  1312. goto out_invalid;
  1313. }
  1314. sbi->max_cluster = total_clusters + FAT_START_ENT;
  1315. /* check the free_clusters, it's not necessarily correct */
  1316. if (sbi->free_clusters != -1 && sbi->free_clusters > total_clusters)
  1317. sbi->free_clusters = -1;
  1318. /* check the prev_free, it's not necessarily correct */
  1319. sbi->prev_free %= sbi->max_cluster;
  1320. if (sbi->prev_free < FAT_START_ENT)
  1321. sbi->prev_free = FAT_START_ENT;
  1322. brelse(bh);
  1323. /* set up enough so that it can read an inode */
  1324. fat_hash_init(sb);
  1325. dir_hash_init(sb);
  1326. fat_ent_access_init(sb);
  1327. /*
  1328. * The low byte of FAT's first entry must have same value with
  1329. * media-field. But in real world, too many devices is
  1330. * writing wrong value. So, removed that validity check.
  1331. *
  1332. * if (FAT_FIRST_ENT(sb, media) != first)
  1333. */
  1334. error = -EINVAL;
  1335. sprintf(buf, "cp%d", sbi->options.codepage);
  1336. sbi->nls_disk = load_nls(buf);
  1337. if (!sbi->nls_disk) {
  1338. fat_msg(sb, KERN_ERR, "codepage %s not found", buf);
  1339. goto out_fail;
  1340. }
  1341. /* FIXME: utf8 is using iocharset for upper/lower conversion */
  1342. if (sbi->options.isvfat) {
  1343. sbi->nls_io = load_nls(sbi->options.iocharset);
  1344. if (!sbi->nls_io) {
  1345. fat_msg(sb, KERN_ERR, "IO charset %s not found",
  1346. sbi->options.iocharset);
  1347. goto out_fail;
  1348. }
  1349. }
  1350. error = -ENOMEM;
  1351. fat_inode = new_inode(sb);
  1352. if (!fat_inode)
  1353. goto out_fail;
  1354. MSDOS_I(fat_inode)->i_pos = 0;
  1355. sbi->fat_inode = fat_inode;
  1356. fsinfo_inode = new_inode(sb);
  1357. if (!fsinfo_inode)
  1358. goto out_fail;
  1359. fsinfo_inode->i_ino = MSDOS_FSINFO_INO;
  1360. sbi->fsinfo_inode = fsinfo_inode;
  1361. insert_inode_hash(fsinfo_inode);
  1362. root_inode = new_inode(sb);
  1363. if (!root_inode)
  1364. goto out_fail;
  1365. root_inode->i_ino = MSDOS_ROOT_INO;
  1366. root_inode->i_version = 1;
  1367. error = fat_read_root(root_inode);
  1368. if (error < 0) {
  1369. iput(root_inode);
  1370. goto out_fail;
  1371. }
  1372. error = -ENOMEM;
  1373. insert_inode_hash(root_inode);
  1374. fat_attach(root_inode, 0);
  1375. sb->s_root = d_make_root(root_inode);
  1376. if (!sb->s_root) {
  1377. fat_msg(sb, KERN_ERR, "get root inode failed");
  1378. goto out_fail;
  1379. }
  1380. if (sbi->options.discard) {
  1381. struct request_queue *q = bdev_get_queue(sb->s_bdev);
  1382. if (!blk_queue_discard(q))
  1383. fat_msg(sb, KERN_WARNING,
  1384. "mounting with \"discard\" option, but "
  1385. "the device does not support discard");
  1386. }
  1387. fat_set_state(sb, 1, 0);
  1388. return 0;
  1389. out_invalid:
  1390. error = -EINVAL;
  1391. if (!silent)
  1392. fat_msg(sb, KERN_INFO, "Can't find a valid FAT filesystem");
  1393. out_fail:
  1394. if (fsinfo_inode)
  1395. iput(fsinfo_inode);
  1396. if (fat_inode)
  1397. iput(fat_inode);
  1398. unload_nls(sbi->nls_io);
  1399. unload_nls(sbi->nls_disk);
  1400. if (sbi->options.iocharset != fat_default_iocharset)
  1401. kfree(sbi->options.iocharset);
  1402. sb->s_fs_info = NULL;
  1403. kfree(sbi);
  1404. return error;
  1405. }
  1406. EXPORT_SYMBOL_GPL(fat_fill_super);
  1407. /*
  1408. * helper function for fat_flush_inodes. This writes both the inode
  1409. * and the file data blocks, waiting for in flight data blocks before
  1410. * the start of the call. It does not wait for any io started
  1411. * during the call
  1412. */
  1413. static int writeback_inode(struct inode *inode)
  1414. {
  1415. int ret;
  1416. /* if we used wait=1, sync_inode_metadata waits for the io for the
  1417. * inode to finish. So wait=0 is sent down to sync_inode_metadata
  1418. * and filemap_fdatawrite is used for the data blocks
  1419. */
  1420. ret = sync_inode_metadata(inode, 0);
  1421. if (!ret)
  1422. ret = filemap_fdatawrite(inode->i_mapping);
  1423. return ret;
  1424. }
  1425. /*
  1426. * write data and metadata corresponding to i1 and i2. The io is
  1427. * started but we do not wait for any of it to finish.
  1428. *
  1429. * filemap_flush is used for the block device, so if there is a dirty
  1430. * page for a block already in flight, we will not wait and start the
  1431. * io over again
  1432. */
  1433. int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2)
  1434. {
  1435. int ret = 0;
  1436. if (!MSDOS_SB(sb)->options.flush)
  1437. return 0;
  1438. if (i1)
  1439. ret = writeback_inode(i1);
  1440. if (!ret && i2)
  1441. ret = writeback_inode(i2);
  1442. if (!ret) {
  1443. struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
  1444. ret = filemap_flush(mapping);
  1445. }
  1446. return ret;
  1447. }
  1448. EXPORT_SYMBOL_GPL(fat_flush_inodes);
  1449. static int __init init_fat_fs(void)
  1450. {
  1451. int err;
  1452. err = fat_cache_init();
  1453. if (err)
  1454. return err;
  1455. err = fat_init_inodecache();
  1456. if (err)
  1457. goto failed;
  1458. return 0;
  1459. failed:
  1460. fat_cache_destroy();
  1461. return err;
  1462. }
  1463. static void __exit exit_fat_fs(void)
  1464. {
  1465. fat_cache_destroy();
  1466. fat_destroy_inodecache();
  1467. }
  1468. module_init(init_fat_fs)
  1469. module_exit(exit_fat_fs)
  1470. MODULE_LICENSE("GPL");