ialloc.c 9.3 KB

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  1. // SPDX-License-Identifier: GPL-2.0
  2. /*
  3. * linux/fs/ufs/ialloc.c
  4. *
  5. * Copyright (c) 1998
  6. * Daniel Pirkl <daniel.pirkl@email.cz>
  7. * Charles University, Faculty of Mathematics and Physics
  8. *
  9. * from
  10. *
  11. * linux/fs/ext2/ialloc.c
  12. *
  13. * Copyright (C) 1992, 1993, 1994, 1995
  14. * Remy Card (card@masi.ibp.fr)
  15. * Laboratoire MASI - Institut Blaise Pascal
  16. * Universite Pierre et Marie Curie (Paris VI)
  17. *
  18. * BSD ufs-inspired inode and directory allocation by
  19. * Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
  20. * Big-endian to little-endian byte-swapping/bitmaps by
  21. * David S. Miller (davem@caip.rutgers.edu), 1995
  22. *
  23. * UFS2 write support added by
  24. * Evgeniy Dushistov <dushistov@mail.ru>, 2007
  25. */
  26. #include <linux/fs.h>
  27. #include <linux/time.h>
  28. #include <linux/stat.h>
  29. #include <linux/string.h>
  30. #include <linux/buffer_head.h>
  31. #include <linux/sched.h>
  32. #include <linux/bitops.h>
  33. #include <asm/byteorder.h>
  34. #include "ufs_fs.h"
  35. #include "ufs.h"
  36. #include "swab.h"
  37. #include "util.h"
  38. /*
  39. * NOTE! When we get the inode, we're the only people
  40. * that have access to it, and as such there are no
  41. * race conditions we have to worry about. The inode
  42. * is not on the hash-lists, and it cannot be reached
  43. * through the filesystem because the directory entry
  44. * has been deleted earlier.
  45. *
  46. * HOWEVER: we must make sure that we get no aliases,
  47. * which means that we have to call "clear_inode()"
  48. * _before_ we mark the inode not in use in the inode
  49. * bitmaps. Otherwise a newly created file might use
  50. * the same inode number (not actually the same pointer
  51. * though), and then we'd have two inodes sharing the
  52. * same inode number and space on the harddisk.
  53. */
  54. void ufs_free_inode (struct inode * inode)
  55. {
  56. struct super_block * sb;
  57. struct ufs_sb_private_info * uspi;
  58. struct ufs_cg_private_info * ucpi;
  59. struct ufs_cylinder_group * ucg;
  60. int is_directory;
  61. unsigned ino, cg, bit;
  62. UFSD("ENTER, ino %lu\n", inode->i_ino);
  63. sb = inode->i_sb;
  64. uspi = UFS_SB(sb)->s_uspi;
  65. ino = inode->i_ino;
  66. mutex_lock(&UFS_SB(sb)->s_lock);
  67. if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) {
  68. ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino);
  69. mutex_unlock(&UFS_SB(sb)->s_lock);
  70. return;
  71. }
  72. cg = ufs_inotocg (ino);
  73. bit = ufs_inotocgoff (ino);
  74. ucpi = ufs_load_cylinder (sb, cg);
  75. if (!ucpi) {
  76. mutex_unlock(&UFS_SB(sb)->s_lock);
  77. return;
  78. }
  79. ucg = ubh_get_ucg(UCPI_UBH(ucpi));
  80. if (!ufs_cg_chkmagic(sb, ucg))
  81. ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number");
  82. ucg->cg_time = ufs_get_seconds(sb);
  83. is_directory = S_ISDIR(inode->i_mode);
  84. if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit))
  85. ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino);
  86. else {
  87. ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit);
  88. if (ino < ucpi->c_irotor)
  89. ucpi->c_irotor = ino;
  90. fs32_add(sb, &ucg->cg_cs.cs_nifree, 1);
  91. uspi->cs_total.cs_nifree++;
  92. fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1);
  93. if (is_directory) {
  94. fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1);
  95. uspi->cs_total.cs_ndir--;
  96. fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1);
  97. }
  98. }
  99. ubh_mark_buffer_dirty (USPI_UBH(uspi));
  100. ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
  101. if (sb->s_flags & SB_SYNCHRONOUS)
  102. ubh_sync_block(UCPI_UBH(ucpi));
  103. ufs_mark_sb_dirty(sb);
  104. mutex_unlock(&UFS_SB(sb)->s_lock);
  105. UFSD("EXIT\n");
  106. }
  107. /*
  108. * Nullify new chunk of inodes,
  109. * BSD people also set ui_gen field of inode
  110. * during nullification, but we not care about
  111. * that because of linux ufs do not support NFS
  112. */
  113. static void ufs2_init_inodes_chunk(struct super_block *sb,
  114. struct ufs_cg_private_info *ucpi,
  115. struct ufs_cylinder_group *ucg)
  116. {
  117. struct buffer_head *bh;
  118. struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
  119. sector_t beg = uspi->s_sbbase +
  120. ufs_inotofsba(ucpi->c_cgx * uspi->s_ipg +
  121. fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk));
  122. sector_t end = beg + uspi->s_fpb;
  123. UFSD("ENTER cgno %d\n", ucpi->c_cgx);
  124. for (; beg < end; ++beg) {
  125. bh = sb_getblk(sb, beg);
  126. lock_buffer(bh);
  127. memset(bh->b_data, 0, sb->s_blocksize);
  128. set_buffer_uptodate(bh);
  129. mark_buffer_dirty(bh);
  130. unlock_buffer(bh);
  131. if (sb->s_flags & SB_SYNCHRONOUS)
  132. sync_dirty_buffer(bh);
  133. brelse(bh);
  134. }
  135. fs32_add(sb, &ucg->cg_u.cg_u2.cg_initediblk, uspi->s_inopb);
  136. ubh_mark_buffer_dirty(UCPI_UBH(ucpi));
  137. if (sb->s_flags & SB_SYNCHRONOUS)
  138. ubh_sync_block(UCPI_UBH(ucpi));
  139. UFSD("EXIT\n");
  140. }
  141. /*
  142. * There are two policies for allocating an inode. If the new inode is
  143. * a directory, then a forward search is made for a block group with both
  144. * free space and a low directory-to-inode ratio; if that fails, then of
  145. * the groups with above-average free space, that group with the fewest
  146. * directories already is chosen.
  147. *
  148. * For other inodes, search forward from the parent directory's block
  149. * group to find a free inode.
  150. */
  151. struct inode *ufs_new_inode(struct inode *dir, umode_t mode)
  152. {
  153. struct super_block * sb;
  154. struct ufs_sb_info * sbi;
  155. struct ufs_sb_private_info * uspi;
  156. struct ufs_cg_private_info * ucpi;
  157. struct ufs_cylinder_group * ucg;
  158. struct inode * inode;
  159. struct timespec64 ts;
  160. unsigned cg, bit, i, j, start;
  161. struct ufs_inode_info *ufsi;
  162. int err = -ENOSPC;
  163. UFSD("ENTER\n");
  164. /* Cannot create files in a deleted directory */
  165. if (!dir || !dir->i_nlink)
  166. return ERR_PTR(-EPERM);
  167. sb = dir->i_sb;
  168. inode = new_inode(sb);
  169. if (!inode)
  170. return ERR_PTR(-ENOMEM);
  171. ufsi = UFS_I(inode);
  172. sbi = UFS_SB(sb);
  173. uspi = sbi->s_uspi;
  174. mutex_lock(&sbi->s_lock);
  175. /*
  176. * Try to place the inode in its parent directory
  177. */
  178. i = ufs_inotocg(dir->i_ino);
  179. if (sbi->fs_cs(i).cs_nifree) {
  180. cg = i;
  181. goto cg_found;
  182. }
  183. /*
  184. * Use a quadratic hash to find a group with a free inode
  185. */
  186. for ( j = 1; j < uspi->s_ncg; j <<= 1 ) {
  187. i += j;
  188. if (i >= uspi->s_ncg)
  189. i -= uspi->s_ncg;
  190. if (sbi->fs_cs(i).cs_nifree) {
  191. cg = i;
  192. goto cg_found;
  193. }
  194. }
  195. /*
  196. * That failed: try linear search for a free inode
  197. */
  198. i = ufs_inotocg(dir->i_ino) + 1;
  199. for (j = 2; j < uspi->s_ncg; j++) {
  200. i++;
  201. if (i >= uspi->s_ncg)
  202. i = 0;
  203. if (sbi->fs_cs(i).cs_nifree) {
  204. cg = i;
  205. goto cg_found;
  206. }
  207. }
  208. goto failed;
  209. cg_found:
  210. ucpi = ufs_load_cylinder (sb, cg);
  211. if (!ucpi) {
  212. err = -EIO;
  213. goto failed;
  214. }
  215. ucg = ubh_get_ucg(UCPI_UBH(ucpi));
  216. if (!ufs_cg_chkmagic(sb, ucg))
  217. ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number");
  218. start = ucpi->c_irotor;
  219. bit = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, uspi->s_ipg, start);
  220. if (!(bit < uspi->s_ipg)) {
  221. bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start);
  222. if (!(bit < start)) {
  223. ufs_error (sb, "ufs_new_inode",
  224. "cylinder group %u corrupted - error in inode bitmap\n", cg);
  225. err = -EIO;
  226. goto failed;
  227. }
  228. }
  229. UFSD("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg);
  230. if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit))
  231. ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit);
  232. else {
  233. ufs_panic (sb, "ufs_new_inode", "internal error");
  234. err = -EIO;
  235. goto failed;
  236. }
  237. if (uspi->fs_magic == UFS2_MAGIC) {
  238. u32 initediblk = fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk);
  239. if (bit + uspi->s_inopb > initediblk &&
  240. initediblk < fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_niblk))
  241. ufs2_init_inodes_chunk(sb, ucpi, ucg);
  242. }
  243. fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1);
  244. uspi->cs_total.cs_nifree--;
  245. fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1);
  246. if (S_ISDIR(mode)) {
  247. fs32_add(sb, &ucg->cg_cs.cs_ndir, 1);
  248. uspi->cs_total.cs_ndir++;
  249. fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1);
  250. }
  251. ubh_mark_buffer_dirty (USPI_UBH(uspi));
  252. ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
  253. if (sb->s_flags & SB_SYNCHRONOUS)
  254. ubh_sync_block(UCPI_UBH(ucpi));
  255. ufs_mark_sb_dirty(sb);
  256. inode->i_ino = cg * uspi->s_ipg + bit;
  257. inode_init_owner(inode, dir, mode);
  258. inode->i_blocks = 0;
  259. inode->i_generation = 0;
  260. inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
  261. ufsi->i_flags = UFS_I(dir)->i_flags;
  262. ufsi->i_lastfrag = 0;
  263. ufsi->i_shadow = 0;
  264. ufsi->i_osync = 0;
  265. ufsi->i_oeftflag = 0;
  266. ufsi->i_dir_start_lookup = 0;
  267. memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1));
  268. if (insert_inode_locked(inode) < 0) {
  269. err = -EIO;
  270. goto failed;
  271. }
  272. mark_inode_dirty(inode);
  273. if (uspi->fs_magic == UFS2_MAGIC) {
  274. struct buffer_head *bh;
  275. struct ufs2_inode *ufs2_inode;
  276. /*
  277. * setup birth date, we do it here because of there is no sense
  278. * to hold it in struct ufs_inode_info, and lose 64 bit
  279. */
  280. bh = sb_bread(sb, uspi->s_sbbase + ufs_inotofsba(inode->i_ino));
  281. if (!bh) {
  282. ufs_warning(sb, "ufs_read_inode",
  283. "unable to read inode %lu\n",
  284. inode->i_ino);
  285. err = -EIO;
  286. goto fail_remove_inode;
  287. }
  288. lock_buffer(bh);
  289. ufs2_inode = (struct ufs2_inode *)bh->b_data;
  290. ufs2_inode += ufs_inotofsbo(inode->i_ino);
  291. ktime_get_real_ts64(&ts);
  292. ufs2_inode->ui_birthtime = cpu_to_fs64(sb, ts.tv_sec);
  293. ufs2_inode->ui_birthnsec = cpu_to_fs32(sb, ts.tv_nsec);
  294. mark_buffer_dirty(bh);
  295. unlock_buffer(bh);
  296. if (sb->s_flags & SB_SYNCHRONOUS)
  297. sync_dirty_buffer(bh);
  298. brelse(bh);
  299. }
  300. mutex_unlock(&sbi->s_lock);
  301. UFSD("allocating inode %lu\n", inode->i_ino);
  302. UFSD("EXIT\n");
  303. return inode;
  304. fail_remove_inode:
  305. mutex_unlock(&sbi->s_lock);
  306. clear_nlink(inode);
  307. discard_new_inode(inode);
  308. UFSD("EXIT (FAILED): err %d\n", err);
  309. return ERR_PTR(err);
  310. failed:
  311. mutex_unlock(&sbi->s_lock);
  312. make_bad_inode(inode);
  313. iput (inode);
  314. UFSD("EXIT (FAILED): err %d\n", err);
  315. return ERR_PTR(err);
  316. }