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/time.h> 28 #include <linux/stat.h> 29 #include <linux/string.h> 30 #include <linux/quotaops.h> 31 #include <linux/buffer_head.h> 32 #include <linux/sched.h> 33 #include <linux/bitops.h> 34 #include <asm/byteorder.h> 35 36 #include "ufs_fs.h" 37 #include "ufs.h" 38 #include "swab.h" 39 #include "util.h" 40 41 /* 42 * NOTE! When we get the inode, we're the only people 43 * that have access to it, and as such there are no 44 * race conditions we have to worry about. The inode 45 * is not on the hash-lists, and it cannot be reached 46 * through the filesystem because the directory entry 47 * has been deleted earlier. 48 * 49 * HOWEVER: we must make sure that we get no aliases, 50 * which means that we have to call "clear_inode()" 51 * _before_ we mark the inode not in use in the inode 52 * bitmaps. Otherwise a newly created file might use 53 * the same inode number (not actually the same pointer 54 * though), and then we'd have two inodes sharing the 55 * same inode number and space on the harddisk. 56 */ 57 void ufs_free_inode (struct inode * inode) 58 { 59 struct super_block * sb; 60 struct ufs_sb_private_info * uspi; 61 struct ufs_super_block_first * usb1; 62 struct ufs_cg_private_info * ucpi; 63 struct ufs_cylinder_group * ucg; 64 int is_directory; 65 unsigned ino, cg, bit; 66 67 UFSD("ENTER, ino %lu\n", inode->i_ino); 68 69 sb = inode->i_sb; 70 uspi = UFS_SB(sb)->s_uspi; 71 usb1 = ubh_get_usb_first(uspi); 72 73 ino = inode->i_ino; 74 75 lock_super (sb); 76 77 if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) { 78 ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino); 79 unlock_super (sb); 80 return; 81 } 82 83 cg = ufs_inotocg (ino); 84 bit = ufs_inotocgoff (ino); 85 ucpi = ufs_load_cylinder (sb, cg); 86 if (!ucpi) { 87 unlock_super (sb); 88 return; 89 } 90 ucg = ubh_get_ucg(UCPI_UBH(ucpi)); 91 if (!ufs_cg_chkmagic(sb, ucg)) 92 ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number"); 93 94 ucg->cg_time = cpu_to_fs32(sb, get_seconds()); 95 96 is_directory = S_ISDIR(inode->i_mode); 97 98 vfs_dq_free_inode(inode); 99 vfs_dq_drop(inode); 100 101 clear_inode (inode); 102 103 if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) 104 ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino); 105 else { 106 ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); 107 if (ino < ucpi->c_irotor) 108 ucpi->c_irotor = ino; 109 fs32_add(sb, &ucg->cg_cs.cs_nifree, 1); 110 uspi->cs_total.cs_nifree++; 111 fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1); 112 113 if (is_directory) { 114 fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1); 115 uspi->cs_total.cs_ndir--; 116 fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1); 117 } 118 } 119 120 ubh_mark_buffer_dirty (USPI_UBH(uspi)); 121 ubh_mark_buffer_dirty (UCPI_UBH(ucpi)); 122 if (sb->s_flags & MS_SYNCHRONOUS) { 123 ubh_ll_rw_block(SWRITE, UCPI_UBH(ucpi)); 124 ubh_wait_on_buffer (UCPI_UBH(ucpi)); 125 } 126 127 sb->s_dirt = 1; 128 unlock_super (sb); 129 UFSD("EXIT\n"); 130 } 131 132 /* 133 * Nullify new chunk of inodes, 134 * BSD people also set ui_gen field of inode 135 * during nullification, but we not care about 136 * that because of linux ufs do not support NFS 137 */ 138 static void ufs2_init_inodes_chunk(struct super_block *sb, 139 struct ufs_cg_private_info *ucpi, 140 struct ufs_cylinder_group *ucg) 141 { 142 struct buffer_head *bh; 143 struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi; 144 sector_t beg = uspi->s_sbbase + 145 ufs_inotofsba(ucpi->c_cgx * uspi->s_ipg + 146 fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk)); 147 sector_t end = beg + uspi->s_fpb; 148 149 UFSD("ENTER cgno %d\n", ucpi->c_cgx); 150 151 for (; beg < end; ++beg) { 152 bh = sb_getblk(sb, beg); 153 lock_buffer(bh); 154 memset(bh->b_data, 0, sb->s_blocksize); 155 set_buffer_uptodate(bh); 156 mark_buffer_dirty(bh); 157 unlock_buffer(bh); 158 if (sb->s_flags & MS_SYNCHRONOUS) 159 sync_dirty_buffer(bh); 160 brelse(bh); 161 } 162 163 fs32_add(sb, &ucg->cg_u.cg_u2.cg_initediblk, uspi->s_inopb); 164 ubh_mark_buffer_dirty(UCPI_UBH(ucpi)); 165 if (sb->s_flags & MS_SYNCHRONOUS) { 166 ubh_ll_rw_block(SWRITE, UCPI_UBH(ucpi)); 167 ubh_wait_on_buffer(UCPI_UBH(ucpi)); 168 } 169 170 UFSD("EXIT\n"); 171 } 172 173 /* 174 * There are two policies for allocating an inode. If the new inode is 175 * a directory, then a forward search is made for a block group with both 176 * free space and a low directory-to-inode ratio; if that fails, then of 177 * the groups with above-average free space, that group with the fewest 178 * directories already is chosen. 179 * 180 * For other inodes, search forward from the parent directory's block 181 * group to find a free inode. 182 */ 183 struct inode * ufs_new_inode(struct inode * dir, int mode) 184 { 185 struct super_block * sb; 186 struct ufs_sb_info * sbi; 187 struct ufs_sb_private_info * uspi; 188 struct ufs_super_block_first * usb1; 189 struct ufs_cg_private_info * ucpi; 190 struct ufs_cylinder_group * ucg; 191 struct inode * inode; 192 unsigned cg, bit, i, j, start; 193 struct ufs_inode_info *ufsi; 194 int err = -ENOSPC; 195 196 UFSD("ENTER\n"); 197 198 /* Cannot create files in a deleted directory */ 199 if (!dir || !dir->i_nlink) 200 return ERR_PTR(-EPERM); 201 sb = dir->i_sb; 202 inode = new_inode(sb); 203 if (!inode) 204 return ERR_PTR(-ENOMEM); 205 ufsi = UFS_I(inode); 206 sbi = UFS_SB(sb); 207 uspi = sbi->s_uspi; 208 usb1 = ubh_get_usb_first(uspi); 209 210 lock_super (sb); 211 212 /* 213 * Try to place the inode in its parent directory 214 */ 215 i = ufs_inotocg(dir->i_ino); 216 if (sbi->fs_cs(i).cs_nifree) { 217 cg = i; 218 goto cg_found; 219 } 220 221 /* 222 * Use a quadratic hash to find a group with a free inode 223 */ 224 for ( j = 1; j < uspi->s_ncg; j <<= 1 ) { 225 i += j; 226 if (i >= uspi->s_ncg) 227 i -= uspi->s_ncg; 228 if (sbi->fs_cs(i).cs_nifree) { 229 cg = i; 230 goto cg_found; 231 } 232 } 233 234 /* 235 * That failed: try linear search for a free inode 236 */ 237 i = ufs_inotocg(dir->i_ino) + 1; 238 for (j = 2; j < uspi->s_ncg; j++) { 239 i++; 240 if (i >= uspi->s_ncg) 241 i = 0; 242 if (sbi->fs_cs(i).cs_nifree) { 243 cg = i; 244 goto cg_found; 245 } 246 } 247 248 goto failed; 249 250 cg_found: 251 ucpi = ufs_load_cylinder (sb, cg); 252 if (!ucpi) { 253 err = -EIO; 254 goto failed; 255 } 256 ucg = ubh_get_ucg(UCPI_UBH(ucpi)); 257 if (!ufs_cg_chkmagic(sb, ucg)) 258 ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number"); 259 260 start = ucpi->c_irotor; 261 bit = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, uspi->s_ipg, start); 262 if (!(bit < uspi->s_ipg)) { 263 bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start); 264 if (!(bit < start)) { 265 ufs_error (sb, "ufs_new_inode", 266 "cylinder group %u corrupted - error in inode bitmap\n", cg); 267 err = -EIO; 268 goto failed; 269 } 270 } 271 UFSD("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg); 272 if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) 273 ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); 274 else { 275 ufs_panic (sb, "ufs_new_inode", "internal error"); 276 err = -EIO; 277 goto failed; 278 } 279 280 if (uspi->fs_magic == UFS2_MAGIC) { 281 u32 initediblk = fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk); 282 283 if (bit + uspi->s_inopb > initediblk && 284 initediblk < fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_niblk)) 285 ufs2_init_inodes_chunk(sb, ucpi, ucg); 286 } 287 288 fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1); 289 uspi->cs_total.cs_nifree--; 290 fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1); 291 292 if (S_ISDIR(mode)) { 293 fs32_add(sb, &ucg->cg_cs.cs_ndir, 1); 294 uspi->cs_total.cs_ndir++; 295 fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1); 296 } 297 ubh_mark_buffer_dirty (USPI_UBH(uspi)); 298 ubh_mark_buffer_dirty (UCPI_UBH(ucpi)); 299 if (sb->s_flags & MS_SYNCHRONOUS) { 300 ubh_ll_rw_block(SWRITE, UCPI_UBH(ucpi)); 301 ubh_wait_on_buffer (UCPI_UBH(ucpi)); 302 } 303 sb->s_dirt = 1; 304 305 inode->i_ino = cg * uspi->s_ipg + bit; 306 inode->i_mode = mode; 307 inode->i_uid = current_fsuid(); 308 if (dir->i_mode & S_ISGID) { 309 inode->i_gid = dir->i_gid; 310 if (S_ISDIR(mode)) 311 inode->i_mode |= S_ISGID; 312 } else 313 inode->i_gid = current_fsgid(); 314 315 inode->i_blocks = 0; 316 inode->i_generation = 0; 317 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC; 318 ufsi->i_flags = UFS_I(dir)->i_flags; 319 ufsi->i_lastfrag = 0; 320 ufsi->i_shadow = 0; 321 ufsi->i_osync = 0; 322 ufsi->i_oeftflag = 0; 323 ufsi->i_dir_start_lookup = 0; 324 memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1)); 325 insert_inode_hash(inode); 326 mark_inode_dirty(inode); 327 328 if (uspi->fs_magic == UFS2_MAGIC) { 329 struct buffer_head *bh; 330 struct ufs2_inode *ufs2_inode; 331 332 /* 333 * setup birth date, we do it here because of there is no sense 334 * to hold it in struct ufs_inode_info, and lose 64 bit 335 */ 336 bh = sb_bread(sb, uspi->s_sbbase + ufs_inotofsba(inode->i_ino)); 337 if (!bh) { 338 ufs_warning(sb, "ufs_read_inode", 339 "unable to read inode %lu\n", 340 inode->i_ino); 341 err = -EIO; 342 goto fail_remove_inode; 343 } 344 lock_buffer(bh); 345 ufs2_inode = (struct ufs2_inode *)bh->b_data; 346 ufs2_inode += ufs_inotofsbo(inode->i_ino); 347 ufs2_inode->ui_birthtime = cpu_to_fs64(sb, CURRENT_TIME.tv_sec); 348 ufs2_inode->ui_birthnsec = cpu_to_fs32(sb, CURRENT_TIME.tv_nsec); 349 mark_buffer_dirty(bh); 350 unlock_buffer(bh); 351 if (sb->s_flags & MS_SYNCHRONOUS) 352 sync_dirty_buffer(bh); 353 brelse(bh); 354 } 355 356 unlock_super (sb); 357 358 if (vfs_dq_alloc_inode(inode)) { 359 vfs_dq_drop(inode); 360 err = -EDQUOT; 361 goto fail_without_unlock; 362 } 363 364 UFSD("allocating inode %lu\n", inode->i_ino); 365 UFSD("EXIT\n"); 366 return inode; 367 368 fail_remove_inode: 369 unlock_super(sb); 370 fail_without_unlock: 371 inode->i_flags |= S_NOQUOTA; 372 inode->i_nlink = 0; 373 iput(inode); 374 UFSD("EXIT (FAILED): err %d\n", err); 375 return ERR_PTR(err); 376 failed: 377 unlock_super (sb); 378 make_bad_inode(inode); 379 iput (inode); 380 UFSD("EXIT (FAILED): err %d\n", err); 381 return ERR_PTR(err); 382 } 383