1 /* 2 * linux/fs/ufs/ialloc.c 3 * 4 * Copyright (c) 1998 5 * Daniel Pirkl <daniel.pirkl@email.cz> 6 * Charles University, Faculty of Mathematics and Physics 7 * 8 * from 9 * 10 * linux/fs/ext2/ialloc.c 11 * 12 * Copyright (C) 1992, 1993, 1994, 1995 13 * Remy Card (card@masi.ibp.fr) 14 * Laboratoire MASI - Institut Blaise Pascal 15 * Universite Pierre et Marie Curie (Paris VI) 16 * 17 * BSD ufs-inspired inode and directory allocation by 18 * Stephen Tweedie (sct@dcs.ed.ac.uk), 1993 19 * Big-endian to little-endian byte-swapping/bitmaps by 20 * David S. Miller (davem@caip.rutgers.edu), 1995 21 * 22 * UFS2 write support added by 23 * Evgeniy Dushistov <dushistov@mail.ru>, 2007 24 */ 25 26 #include <linux/fs.h> 27 #include <linux/ufs_fs.h> 28 #include <linux/time.h> 29 #include <linux/stat.h> 30 #include <linux/string.h> 31 #include <linux/quotaops.h> 32 #include <linux/buffer_head.h> 33 #include <linux/sched.h> 34 #include <linux/bitops.h> 35 #include <asm/byteorder.h> 36 37 #include "swab.h" 38 #include "util.h" 39 40 /* 41 * NOTE! When we get the inode, we're the only people 42 * that have access to it, and as such there are no 43 * race conditions we have to worry about. The inode 44 * is not on the hash-lists, and it cannot be reached 45 * through the filesystem because the directory entry 46 * has been deleted earlier. 47 * 48 * HOWEVER: we must make sure that we get no aliases, 49 * which means that we have to call "clear_inode()" 50 * _before_ we mark the inode not in use in the inode 51 * bitmaps. Otherwise a newly created file might use 52 * the same inode number (not actually the same pointer 53 * though), and then we'd have two inodes sharing the 54 * same inode number and space on the harddisk. 55 */ 56 void ufs_free_inode (struct inode * inode) 57 { 58 struct super_block * sb; 59 struct ufs_sb_private_info * uspi; 60 struct ufs_super_block_first * usb1; 61 struct ufs_cg_private_info * ucpi; 62 struct ufs_cylinder_group * ucg; 63 int is_directory; 64 unsigned ino, cg, bit; 65 66 UFSD("ENTER, ino %lu\n", inode->i_ino); 67 68 sb = inode->i_sb; 69 uspi = UFS_SB(sb)->s_uspi; 70 usb1 = ubh_get_usb_first(uspi); 71 72 ino = inode->i_ino; 73 74 lock_super (sb); 75 76 if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) { 77 ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino); 78 unlock_super (sb); 79 return; 80 } 81 82 cg = ufs_inotocg (ino); 83 bit = ufs_inotocgoff (ino); 84 ucpi = ufs_load_cylinder (sb, cg); 85 if (!ucpi) { 86 unlock_super (sb); 87 return; 88 } 89 ucg = ubh_get_ucg(UCPI_UBH(ucpi)); 90 if (!ufs_cg_chkmagic(sb, ucg)) 91 ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number"); 92 93 ucg->cg_time = cpu_to_fs32(sb, get_seconds()); 94 95 is_directory = S_ISDIR(inode->i_mode); 96 97 DQUOT_FREE_INODE(inode); 98 DQUOT_DROP(inode); 99 100 clear_inode (inode); 101 102 if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) 103 ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino); 104 else { 105 ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); 106 if (ino < ucpi->c_irotor) 107 ucpi->c_irotor = ino; 108 fs32_add(sb, &ucg->cg_cs.cs_nifree, 1); 109 uspi->cs_total.cs_nifree++; 110 fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1); 111 112 if (is_directory) { 113 fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1); 114 uspi->cs_total.cs_ndir--; 115 fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1); 116 } 117 } 118 119 ubh_mark_buffer_dirty (USPI_UBH(uspi)); 120 ubh_mark_buffer_dirty (UCPI_UBH(ucpi)); 121 if (sb->s_flags & MS_SYNCHRONOUS) { 122 ubh_ll_rw_block(SWRITE, UCPI_UBH(ucpi)); 123 ubh_wait_on_buffer (UCPI_UBH(ucpi)); 124 } 125 126 sb->s_dirt = 1; 127 unlock_super (sb); 128 UFSD("EXIT\n"); 129 } 130 131 /* 132 * Nullify new chunk of inodes, 133 * BSD people also set ui_gen field of inode 134 * during nullification, but we not care about 135 * that because of linux ufs do not support NFS 136 */ 137 static void ufs2_init_inodes_chunk(struct super_block *sb, 138 struct ufs_cg_private_info *ucpi, 139 struct ufs_cylinder_group *ucg) 140 { 141 struct buffer_head *bh; 142 struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi; 143 sector_t beg = uspi->s_sbbase + 144 ufs_inotofsba(ucpi->c_cgx * uspi->s_ipg + 145 fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk)); 146 sector_t end = beg + uspi->s_fpb; 147 148 UFSD("ENTER cgno %d\n", ucpi->c_cgx); 149 150 for (; beg < end; ++beg) { 151 bh = sb_getblk(sb, beg); 152 lock_buffer(bh); 153 memset(bh->b_data, 0, sb->s_blocksize); 154 set_buffer_uptodate(bh); 155 mark_buffer_dirty(bh); 156 unlock_buffer(bh); 157 if (sb->s_flags & MS_SYNCHRONOUS) 158 sync_dirty_buffer(bh); 159 brelse(bh); 160 } 161 162 fs32_add(sb, &ucg->cg_u.cg_u2.cg_initediblk, uspi->s_inopb); 163 ubh_mark_buffer_dirty(UCPI_UBH(ucpi)); 164 if (sb->s_flags & MS_SYNCHRONOUS) { 165 ubh_ll_rw_block(SWRITE, UCPI_UBH(ucpi)); 166 ubh_wait_on_buffer(UCPI_UBH(ucpi)); 167 } 168 169 UFSD("EXIT\n"); 170 } 171 172 /* 173 * There are two policies for allocating an inode. If the new inode is 174 * a directory, then a forward search is made for a block group with both 175 * free space and a low directory-to-inode ratio; if that fails, then of 176 * the groups with above-average free space, that group with the fewest 177 * directories already is chosen. 178 * 179 * For other inodes, search forward from the parent directory's block 180 * group to find a free inode. 181 */ 182 struct inode * ufs_new_inode(struct inode * dir, int mode) 183 { 184 struct super_block * sb; 185 struct ufs_sb_info * sbi; 186 struct ufs_sb_private_info * uspi; 187 struct ufs_super_block_first * usb1; 188 struct ufs_cg_private_info * ucpi; 189 struct ufs_cylinder_group * ucg; 190 struct inode * inode; 191 unsigned cg, bit, i, j, start; 192 struct ufs_inode_info *ufsi; 193 int err = -ENOSPC; 194 195 UFSD("ENTER\n"); 196 197 /* Cannot create files in a deleted directory */ 198 if (!dir || !dir->i_nlink) 199 return ERR_PTR(-EPERM); 200 sb = dir->i_sb; 201 inode = new_inode(sb); 202 if (!inode) 203 return ERR_PTR(-ENOMEM); 204 ufsi = UFS_I(inode); 205 sbi = UFS_SB(sb); 206 uspi = sbi->s_uspi; 207 usb1 = ubh_get_usb_first(uspi); 208 209 lock_super (sb); 210 211 /* 212 * Try to place the inode in its parent directory 213 */ 214 i = ufs_inotocg(dir->i_ino); 215 if (sbi->fs_cs(i).cs_nifree) { 216 cg = i; 217 goto cg_found; 218 } 219 220 /* 221 * Use a quadratic hash to find a group with a free inode 222 */ 223 for ( j = 1; j < uspi->s_ncg; j <<= 1 ) { 224 i += j; 225 if (i >= uspi->s_ncg) 226 i -= uspi->s_ncg; 227 if (sbi->fs_cs(i).cs_nifree) { 228 cg = i; 229 goto cg_found; 230 } 231 } 232 233 /* 234 * That failed: try linear search for a free inode 235 */ 236 i = ufs_inotocg(dir->i_ino) + 1; 237 for (j = 2; j < uspi->s_ncg; j++) { 238 i++; 239 if (i >= uspi->s_ncg) 240 i = 0; 241 if (sbi->fs_cs(i).cs_nifree) { 242 cg = i; 243 goto cg_found; 244 } 245 } 246 247 goto failed; 248 249 cg_found: 250 ucpi = ufs_load_cylinder (sb, cg); 251 if (!ucpi) { 252 err = -EIO; 253 goto failed; 254 } 255 ucg = ubh_get_ucg(UCPI_UBH(ucpi)); 256 if (!ufs_cg_chkmagic(sb, ucg)) 257 ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number"); 258 259 start = ucpi->c_irotor; 260 bit = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, uspi->s_ipg, start); 261 if (!(bit < uspi->s_ipg)) { 262 bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start); 263 if (!(bit < start)) { 264 ufs_error (sb, "ufs_new_inode", 265 "cylinder group %u corrupted - error in inode bitmap\n", cg); 266 err = -EIO; 267 goto failed; 268 } 269 } 270 UFSD("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg); 271 if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) 272 ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); 273 else { 274 ufs_panic (sb, "ufs_new_inode", "internal error"); 275 err = -EIO; 276 goto failed; 277 } 278 279 if (uspi->fs_magic == UFS2_MAGIC) { 280 u32 initediblk = fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk); 281 282 if (bit + uspi->s_inopb > initediblk && 283 initediblk < fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_niblk)) 284 ufs2_init_inodes_chunk(sb, ucpi, ucg); 285 } 286 287 fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1); 288 uspi->cs_total.cs_nifree--; 289 fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1); 290 291 if (S_ISDIR(mode)) { 292 fs32_add(sb, &ucg->cg_cs.cs_ndir, 1); 293 uspi->cs_total.cs_ndir++; 294 fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1); 295 } 296 ubh_mark_buffer_dirty (USPI_UBH(uspi)); 297 ubh_mark_buffer_dirty (UCPI_UBH(ucpi)); 298 if (sb->s_flags & MS_SYNCHRONOUS) { 299 ubh_ll_rw_block(SWRITE, UCPI_UBH(ucpi)); 300 ubh_wait_on_buffer (UCPI_UBH(ucpi)); 301 } 302 sb->s_dirt = 1; 303 304 inode->i_ino = cg * uspi->s_ipg + bit; 305 inode->i_mode = mode; 306 inode->i_uid = current->fsuid; 307 if (dir->i_mode & S_ISGID) { 308 inode->i_gid = dir->i_gid; 309 if (S_ISDIR(mode)) 310 inode->i_mode |= S_ISGID; 311 } else 312 inode->i_gid = current->fsgid; 313 314 inode->i_blocks = 0; 315 inode->i_generation = 0; 316 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC; 317 ufsi->i_flags = UFS_I(dir)->i_flags; 318 ufsi->i_lastfrag = 0; 319 ufsi->i_shadow = 0; 320 ufsi->i_osync = 0; 321 ufsi->i_oeftflag = 0; 322 ufsi->i_dir_start_lookup = 0; 323 memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1)); 324 insert_inode_hash(inode); 325 mark_inode_dirty(inode); 326 327 if (uspi->fs_magic == UFS2_MAGIC) { 328 struct buffer_head *bh; 329 struct ufs2_inode *ufs2_inode; 330 331 /* 332 * setup birth date, we do it here because of there is no sense 333 * to hold it in struct ufs_inode_info, and lose 64 bit 334 */ 335 bh = sb_bread(sb, uspi->s_sbbase + ufs_inotofsba(inode->i_ino)); 336 if (!bh) { 337 ufs_warning(sb, "ufs_read_inode", 338 "unable to read inode %lu\n", 339 inode->i_ino); 340 err = -EIO; 341 goto fail_remove_inode; 342 } 343 lock_buffer(bh); 344 ufs2_inode = (struct ufs2_inode *)bh->b_data; 345 ufs2_inode += ufs_inotofsbo(inode->i_ino); 346 ufs2_inode->ui_birthtime = cpu_to_fs64(sb, CURRENT_TIME.tv_sec); 347 ufs2_inode->ui_birthnsec = cpu_to_fs32(sb, CURRENT_TIME.tv_nsec); 348 mark_buffer_dirty(bh); 349 unlock_buffer(bh); 350 if (sb->s_flags & MS_SYNCHRONOUS) 351 sync_dirty_buffer(bh); 352 brelse(bh); 353 } 354 355 unlock_super (sb); 356 357 if (DQUOT_ALLOC_INODE(inode)) { 358 DQUOT_DROP(inode); 359 err = -EDQUOT; 360 goto fail_without_unlock; 361 } 362 363 UFSD("allocating inode %lu\n", inode->i_ino); 364 UFSD("EXIT\n"); 365 return inode; 366 367 fail_remove_inode: 368 unlock_super(sb); 369 fail_without_unlock: 370 inode->i_flags |= S_NOQUOTA; 371 inode->i_nlink = 0; 372 iput(inode); 373 UFSD("EXIT (FAILED): err %d\n", err); 374 return ERR_PTR(err); 375 failed: 376 unlock_super (sb); 377 make_bad_inode(inode); 378 iput (inode); 379 UFSD("EXIT (FAILED): err %d\n", err); 380 return ERR_PTR(err); 381 } 382