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 27 #include <linux/fs.h> 28 #include <linux/time.h> 29 #include <linux/stat.h> 30 #include <linux/string.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_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 71 ino = inode->i_ino; 72 73 mutex_lock(&UFS_SB(sb)->s_lock); 74 75 if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) { 76 ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino); 77 mutex_unlock(&UFS_SB(sb)->s_lock); 78 return; 79 } 80 81 cg = ufs_inotocg (ino); 82 bit = ufs_inotocgoff (ino); 83 ucpi = ufs_load_cylinder (sb, cg); 84 if (!ucpi) { 85 mutex_unlock(&UFS_SB(sb)->s_lock); 86 return; 87 } 88 ucg = ubh_get_ucg(UCPI_UBH(ucpi)); 89 if (!ufs_cg_chkmagic(sb, ucg)) 90 ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number"); 91 92 ucg->cg_time = ufs_get_seconds(sb); 93 94 is_directory = S_ISDIR(inode->i_mode); 95 96 if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) 97 ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino); 98 else { 99 ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); 100 if (ino < ucpi->c_irotor) 101 ucpi->c_irotor = ino; 102 fs32_add(sb, &ucg->cg_cs.cs_nifree, 1); 103 uspi->cs_total.cs_nifree++; 104 fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1); 105 106 if (is_directory) { 107 fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1); 108 uspi->cs_total.cs_ndir--; 109 fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1); 110 } 111 } 112 113 ubh_mark_buffer_dirty (USPI_UBH(uspi)); 114 ubh_mark_buffer_dirty (UCPI_UBH(ucpi)); 115 if (sb->s_flags & SB_SYNCHRONOUS) 116 ubh_sync_block(UCPI_UBH(ucpi)); 117 118 ufs_mark_sb_dirty(sb); 119 mutex_unlock(&UFS_SB(sb)->s_lock); 120 UFSD("EXIT\n"); 121 } 122 123 /* 124 * Nullify new chunk of inodes, 125 * BSD people also set ui_gen field of inode 126 * during nullification, but we not care about 127 * that because of linux ufs do not support NFS 128 */ 129 static void ufs2_init_inodes_chunk(struct super_block *sb, 130 struct ufs_cg_private_info *ucpi, 131 struct ufs_cylinder_group *ucg) 132 { 133 struct buffer_head *bh; 134 struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi; 135 sector_t beg = uspi->s_sbbase + 136 ufs_inotofsba(ucpi->c_cgx * uspi->s_ipg + 137 fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk)); 138 sector_t end = beg + uspi->s_fpb; 139 140 UFSD("ENTER cgno %d\n", ucpi->c_cgx); 141 142 for (; beg < end; ++beg) { 143 bh = sb_getblk(sb, beg); 144 lock_buffer(bh); 145 memset(bh->b_data, 0, sb->s_blocksize); 146 set_buffer_uptodate(bh); 147 mark_buffer_dirty(bh); 148 unlock_buffer(bh); 149 if (sb->s_flags & SB_SYNCHRONOUS) 150 sync_dirty_buffer(bh); 151 brelse(bh); 152 } 153 154 fs32_add(sb, &ucg->cg_u.cg_u2.cg_initediblk, uspi->s_inopb); 155 ubh_mark_buffer_dirty(UCPI_UBH(ucpi)); 156 if (sb->s_flags & SB_SYNCHRONOUS) 157 ubh_sync_block(UCPI_UBH(ucpi)); 158 159 UFSD("EXIT\n"); 160 } 161 162 /* 163 * There are two policies for allocating an inode. If the new inode is 164 * a directory, then a forward search is made for a block group with both 165 * free space and a low directory-to-inode ratio; if that fails, then of 166 * the groups with above-average free space, that group with the fewest 167 * directories already is chosen. 168 * 169 * For other inodes, search forward from the parent directory's block 170 * group to find a free inode. 171 */ 172 struct inode *ufs_new_inode(struct inode *dir, umode_t mode) 173 { 174 struct super_block * sb; 175 struct ufs_sb_info * sbi; 176 struct ufs_sb_private_info * uspi; 177 struct ufs_cg_private_info * ucpi; 178 struct ufs_cylinder_group * ucg; 179 struct inode * inode; 180 struct timespec64 ts; 181 unsigned cg, bit, i, j, start; 182 struct ufs_inode_info *ufsi; 183 int err = -ENOSPC; 184 185 UFSD("ENTER\n"); 186 187 /* Cannot create files in a deleted directory */ 188 if (!dir || !dir->i_nlink) 189 return ERR_PTR(-EPERM); 190 sb = dir->i_sb; 191 inode = new_inode(sb); 192 if (!inode) 193 return ERR_PTR(-ENOMEM); 194 ufsi = UFS_I(inode); 195 sbi = UFS_SB(sb); 196 uspi = sbi->s_uspi; 197 198 mutex_lock(&sbi->s_lock); 199 200 /* 201 * Try to place the inode in its parent directory 202 */ 203 i = ufs_inotocg(dir->i_ino); 204 if (sbi->fs_cs(i).cs_nifree) { 205 cg = i; 206 goto cg_found; 207 } 208 209 /* 210 * Use a quadratic hash to find a group with a free inode 211 */ 212 for ( j = 1; j < uspi->s_ncg; j <<= 1 ) { 213 i += j; 214 if (i >= uspi->s_ncg) 215 i -= uspi->s_ncg; 216 if (sbi->fs_cs(i).cs_nifree) { 217 cg = i; 218 goto cg_found; 219 } 220 } 221 222 /* 223 * That failed: try linear search for a free inode 224 */ 225 i = ufs_inotocg(dir->i_ino) + 1; 226 for (j = 2; j < uspi->s_ncg; j++) { 227 i++; 228 if (i >= uspi->s_ncg) 229 i = 0; 230 if (sbi->fs_cs(i).cs_nifree) { 231 cg = i; 232 goto cg_found; 233 } 234 } 235 236 goto failed; 237 238 cg_found: 239 ucpi = ufs_load_cylinder (sb, cg); 240 if (!ucpi) { 241 err = -EIO; 242 goto failed; 243 } 244 ucg = ubh_get_ucg(UCPI_UBH(ucpi)); 245 if (!ufs_cg_chkmagic(sb, ucg)) 246 ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number"); 247 248 start = ucpi->c_irotor; 249 bit = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, uspi->s_ipg, start); 250 if (!(bit < uspi->s_ipg)) { 251 bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start); 252 if (!(bit < start)) { 253 ufs_error (sb, "ufs_new_inode", 254 "cylinder group %u corrupted - error in inode bitmap\n", cg); 255 err = -EIO; 256 goto failed; 257 } 258 } 259 UFSD("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg); 260 if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) 261 ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); 262 else { 263 ufs_panic (sb, "ufs_new_inode", "internal error"); 264 err = -EIO; 265 goto failed; 266 } 267 268 if (uspi->fs_magic == UFS2_MAGIC) { 269 u32 initediblk = fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk); 270 271 if (bit + uspi->s_inopb > initediblk && 272 initediblk < fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_niblk)) 273 ufs2_init_inodes_chunk(sb, ucpi, ucg); 274 } 275 276 fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1); 277 uspi->cs_total.cs_nifree--; 278 fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1); 279 280 if (S_ISDIR(mode)) { 281 fs32_add(sb, &ucg->cg_cs.cs_ndir, 1); 282 uspi->cs_total.cs_ndir++; 283 fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1); 284 } 285 ubh_mark_buffer_dirty (USPI_UBH(uspi)); 286 ubh_mark_buffer_dirty (UCPI_UBH(ucpi)); 287 if (sb->s_flags & SB_SYNCHRONOUS) 288 ubh_sync_block(UCPI_UBH(ucpi)); 289 ufs_mark_sb_dirty(sb); 290 291 inode->i_ino = cg * uspi->s_ipg + bit; 292 inode_init_owner(&nop_mnt_idmap, inode, dir, mode); 293 inode->i_blocks = 0; 294 inode->i_generation = 0; 295 simple_inode_init_ts(inode); 296 ufsi->i_flags = UFS_I(dir)->i_flags; 297 ufsi->i_lastfrag = 0; 298 ufsi->i_shadow = 0; 299 ufsi->i_osync = 0; 300 ufsi->i_oeftflag = 0; 301 ufsi->i_dir_start_lookup = 0; 302 memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1)); 303 if (insert_inode_locked(inode) < 0) { 304 err = -EIO; 305 goto failed; 306 } 307 mark_inode_dirty(inode); 308 309 if (uspi->fs_magic == UFS2_MAGIC) { 310 struct buffer_head *bh; 311 struct ufs2_inode *ufs2_inode; 312 313 /* 314 * setup birth date, we do it here because of there is no sense 315 * to hold it in struct ufs_inode_info, and lose 64 bit 316 */ 317 bh = sb_bread(sb, uspi->s_sbbase + ufs_inotofsba(inode->i_ino)); 318 if (!bh) { 319 ufs_warning(sb, "ufs_read_inode", 320 "unable to read inode %lu\n", 321 inode->i_ino); 322 err = -EIO; 323 goto fail_remove_inode; 324 } 325 lock_buffer(bh); 326 ufs2_inode = (struct ufs2_inode *)bh->b_data; 327 ufs2_inode += ufs_inotofsbo(inode->i_ino); 328 ktime_get_real_ts64(&ts); 329 ufs2_inode->ui_birthtime = cpu_to_fs64(sb, ts.tv_sec); 330 ufs2_inode->ui_birthnsec = cpu_to_fs32(sb, ts.tv_nsec); 331 mark_buffer_dirty(bh); 332 unlock_buffer(bh); 333 if (sb->s_flags & SB_SYNCHRONOUS) 334 sync_dirty_buffer(bh); 335 brelse(bh); 336 } 337 mutex_unlock(&sbi->s_lock); 338 339 UFSD("allocating inode %lu\n", inode->i_ino); 340 UFSD("EXIT\n"); 341 return inode; 342 343 fail_remove_inode: 344 mutex_unlock(&sbi->s_lock); 345 clear_nlink(inode); 346 discard_new_inode(inode); 347 UFSD("EXIT (FAILED): err %d\n", err); 348 return ERR_PTR(err); 349 failed: 350 mutex_unlock(&sbi->s_lock); 351 make_bad_inode(inode); 352 iput (inode); 353 UFSD("EXIT (FAILED): err %d\n", err); 354 return ERR_PTR(err); 355 } 356