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 23 #include <linux/fs.h> 24 #include <linux/ufs_fs.h> 25 #include <linux/time.h> 26 #include <linux/stat.h> 27 #include <linux/string.h> 28 #include <linux/quotaops.h> 29 #include <linux/buffer_head.h> 30 #include <linux/sched.h> 31 #include <linux/bitops.h> 32 #include <asm/byteorder.h> 33 34 #include "swab.h" 35 #include "util.h" 36 37 #undef UFS_IALLOC_DEBUG 38 39 #ifdef UFS_IALLOC_DEBUG 40 #define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x; 41 #else 42 #define UFSD(x) 43 #endif 44 45 /* 46 * NOTE! When we get the inode, we're the only people 47 * that have access to it, and as such there are no 48 * race conditions we have to worry about. The inode 49 * is not on the hash-lists, and it cannot be reached 50 * through the filesystem because the directory entry 51 * has been deleted earlier. 52 * 53 * HOWEVER: we must make sure that we get no aliases, 54 * which means that we have to call "clear_inode()" 55 * _before_ we mark the inode not in use in the inode 56 * bitmaps. Otherwise a newly created file might use 57 * the same inode number (not actually the same pointer 58 * though), and then we'd have two inodes sharing the 59 * same inode number and space on the harddisk. 60 */ 61 void ufs_free_inode (struct inode * inode) 62 { 63 struct super_block * sb; 64 struct ufs_sb_private_info * uspi; 65 struct ufs_super_block_first * usb1; 66 struct ufs_cg_private_info * ucpi; 67 struct ufs_cylinder_group * ucg; 68 int is_directory; 69 unsigned ino, cg, bit; 70 71 UFSD(("ENTER, ino %lu\n", inode->i_ino)) 72 73 sb = inode->i_sb; 74 uspi = UFS_SB(sb)->s_uspi; 75 usb1 = ubh_get_usb_first(USPI_UBH); 76 77 ino = inode->i_ino; 78 79 lock_super (sb); 80 81 if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) { 82 ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino); 83 unlock_super (sb); 84 return; 85 } 86 87 cg = ufs_inotocg (ino); 88 bit = ufs_inotocgoff (ino); 89 ucpi = ufs_load_cylinder (sb, cg); 90 if (!ucpi) { 91 unlock_super (sb); 92 return; 93 } 94 ucg = ubh_get_ucg(UCPI_UBH); 95 if (!ufs_cg_chkmagic(sb, ucg)) 96 ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number"); 97 98 ucg->cg_time = cpu_to_fs32(sb, get_seconds()); 99 100 is_directory = S_ISDIR(inode->i_mode); 101 102 DQUOT_FREE_INODE(inode); 103 DQUOT_DROP(inode); 104 105 clear_inode (inode); 106 107 if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit)) 108 ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino); 109 else { 110 ubh_clrbit (UCPI_UBH, ucpi->c_iusedoff, bit); 111 if (ino < ucpi->c_irotor) 112 ucpi->c_irotor = ino; 113 fs32_add(sb, &ucg->cg_cs.cs_nifree, 1); 114 fs32_add(sb, &usb1->fs_cstotal.cs_nifree, 1); 115 fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1); 116 117 if (is_directory) { 118 fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1); 119 fs32_sub(sb, &usb1->fs_cstotal.cs_ndir, 1); 120 fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1); 121 } 122 } 123 124 ubh_mark_buffer_dirty (USPI_UBH); 125 ubh_mark_buffer_dirty (UCPI_UBH); 126 if (sb->s_flags & MS_SYNCHRONOUS) { 127 ubh_wait_on_buffer (UCPI_UBH); 128 ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi); 129 ubh_wait_on_buffer (UCPI_UBH); 130 } 131 132 sb->s_dirt = 1; 133 unlock_super (sb); 134 UFSD(("EXIT\n")) 135 } 136 137 /* 138 * There are two policies for allocating an inode. If the new inode is 139 * a directory, then a forward search is made for a block group with both 140 * free space and a low directory-to-inode ratio; if that fails, then of 141 * the groups with above-average free space, that group with the fewest 142 * directories already is chosen. 143 * 144 * For other inodes, search forward from the parent directory's block 145 * group to find a free inode. 146 */ 147 struct inode * ufs_new_inode(struct inode * dir, int mode) 148 { 149 struct super_block * sb; 150 struct ufs_sb_info * sbi; 151 struct ufs_sb_private_info * uspi; 152 struct ufs_super_block_first * usb1; 153 struct ufs_cg_private_info * ucpi; 154 struct ufs_cylinder_group * ucg; 155 struct inode * inode; 156 unsigned cg, bit, i, j, start; 157 struct ufs_inode_info *ufsi; 158 159 UFSD(("ENTER\n")) 160 161 /* Cannot create files in a deleted directory */ 162 if (!dir || !dir->i_nlink) 163 return ERR_PTR(-EPERM); 164 sb = dir->i_sb; 165 inode = new_inode(sb); 166 if (!inode) 167 return ERR_PTR(-ENOMEM); 168 ufsi = UFS_I(inode); 169 sbi = UFS_SB(sb); 170 uspi = sbi->s_uspi; 171 usb1 = ubh_get_usb_first(USPI_UBH); 172 173 lock_super (sb); 174 175 /* 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 /* 185 * Use a quadratic hash to find a group with a free inode 186 */ 187 for ( j = 1; j < uspi->s_ncg; j <<= 1 ) { 188 i += j; 189 if (i >= uspi->s_ncg) 190 i -= uspi->s_ncg; 191 if (sbi->fs_cs(i).cs_nifree) { 192 cg = i; 193 goto cg_found; 194 } 195 } 196 197 /* 198 * That failed: try linear search for a free inode 199 */ 200 i = ufs_inotocg(dir->i_ino) + 1; 201 for (j = 2; j < uspi->s_ncg; j++) { 202 i++; 203 if (i >= uspi->s_ncg) 204 i = 0; 205 if (sbi->fs_cs(i).cs_nifree) { 206 cg = i; 207 goto cg_found; 208 } 209 } 210 211 goto failed; 212 213 cg_found: 214 ucpi = ufs_load_cylinder (sb, cg); 215 if (!ucpi) 216 goto failed; 217 ucg = ubh_get_ucg(UCPI_UBH); 218 if (!ufs_cg_chkmagic(sb, ucg)) 219 ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number"); 220 221 start = ucpi->c_irotor; 222 bit = ubh_find_next_zero_bit (UCPI_UBH, ucpi->c_iusedoff, uspi->s_ipg, start); 223 if (!(bit < uspi->s_ipg)) { 224 bit = ubh_find_first_zero_bit (UCPI_UBH, ucpi->c_iusedoff, start); 225 if (!(bit < start)) { 226 ufs_error (sb, "ufs_new_inode", 227 "cylinder group %u corrupted - error in inode bitmap\n", cg); 228 goto failed; 229 } 230 } 231 UFSD(("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg)) 232 if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit)) 233 ubh_setbit (UCPI_UBH, ucpi->c_iusedoff, bit); 234 else { 235 ufs_panic (sb, "ufs_new_inode", "internal error"); 236 goto failed; 237 } 238 239 fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1); 240 fs32_sub(sb, &usb1->fs_cstotal.cs_nifree, 1); 241 fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1); 242 243 if (S_ISDIR(mode)) { 244 fs32_add(sb, &ucg->cg_cs.cs_ndir, 1); 245 fs32_add(sb, &usb1->fs_cstotal.cs_ndir, 1); 246 fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1); 247 } 248 249 ubh_mark_buffer_dirty (USPI_UBH); 250 ubh_mark_buffer_dirty (UCPI_UBH); 251 if (sb->s_flags & MS_SYNCHRONOUS) { 252 ubh_wait_on_buffer (UCPI_UBH); 253 ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi); 254 ubh_wait_on_buffer (UCPI_UBH); 255 } 256 sb->s_dirt = 1; 257 258 inode->i_mode = mode; 259 inode->i_uid = current->fsuid; 260 if (dir->i_mode & S_ISGID) { 261 inode->i_gid = dir->i_gid; 262 if (S_ISDIR(mode)) 263 inode->i_mode |= S_ISGID; 264 } else 265 inode->i_gid = current->fsgid; 266 267 inode->i_ino = cg * uspi->s_ipg + bit; 268 inode->i_blksize = PAGE_SIZE; /* This is the optimal IO size (for stat), not the fs block size */ 269 inode->i_blocks = 0; 270 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC; 271 ufsi->i_flags = UFS_I(dir)->i_flags; 272 ufsi->i_lastfrag = 0; 273 ufsi->i_gen = 0; 274 ufsi->i_shadow = 0; 275 ufsi->i_osync = 0; 276 ufsi->i_oeftflag = 0; 277 memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1)); 278 279 insert_inode_hash(inode); 280 mark_inode_dirty(inode); 281 282 unlock_super (sb); 283 284 if (DQUOT_ALLOC_INODE(inode)) { 285 DQUOT_DROP(inode); 286 inode->i_flags |= S_NOQUOTA; 287 inode->i_nlink = 0; 288 iput(inode); 289 return ERR_PTR(-EDQUOT); 290 } 291 292 UFSD(("allocating inode %lu\n", inode->i_ino)) 293 UFSD(("EXIT\n")) 294 return inode; 295 296 failed: 297 unlock_super (sb); 298 make_bad_inode(inode); 299 iput (inode); 300 UFSD(("EXIT (FAILED)\n")) 301 return ERR_PTR(-ENOSPC); 302 } 303