1 /*- 2 * modified for EXT2FS support in Lites 1.1 3 * 4 * Aug 1995, Godmar Back (gback@cs.utah.edu) 5 * University of Utah, Department of Computer Science 6 * 7 * $FreeBSD$ 8 */ 9 /*- 10 * Copyright (c) 2009 Aditya Sarawgi 11 * All rights reserved. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * 35 */ 36 37 #ifndef _FS_EXT2FS_EXT2_FS_H_ 38 #define _FS_EXT2FS_EXT2_FS_H_ 39 40 #include <sys/types.h> 41 42 /* 43 * Maximal count of links to a file 44 */ 45 #define EXT2_LINK_MAX 32000 46 47 /* 48 * Constants relative to the data blocks 49 */ 50 #define EXT2_NDIR_BLOCKS 12 51 #define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS 52 #define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1) 53 #define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1) 54 #define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1) 55 #define EXT2_MAXSYMLINKLEN (EXT2_N_BLOCKS * sizeof (uint32_t)) 56 57 /* 58 * The path name on which the file system is mounted is maintained 59 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 60 * the super block for this name. 61 */ 62 #define MAXMNTLEN 512 63 64 /* 65 * Super block for an ext2fs file system. 66 */ 67 struct ext2fs { 68 u_int32_t e2fs_icount; /* Inode count */ 69 u_int32_t e2fs_bcount; /* blocks count */ 70 u_int32_t e2fs_rbcount; /* reserved blocks count */ 71 u_int32_t e2fs_fbcount; /* free blocks count */ 72 u_int32_t e2fs_ficount; /* free inodes count */ 73 u_int32_t e2fs_first_dblock; /* first data block */ 74 u_int32_t e2fs_log_bsize; /* block size = 1024*(2^e2fs_log_bsize) */ 75 u_int32_t e2fs_log_fsize; /* fragment size */ 76 u_int32_t e2fs_bpg; /* blocks per group */ 77 u_int32_t e2fs_fpg; /* frags per group */ 78 u_int32_t e2fs_ipg; /* inodes per group */ 79 u_int32_t e2fs_mtime; /* mount time */ 80 u_int32_t e2fs_wtime; /* write time */ 81 u_int16_t e2fs_mnt_count; /* mount count */ 82 u_int16_t e2fs_max_mnt_count; /* max mount count */ 83 u_int16_t e2fs_magic; /* magic number */ 84 u_int16_t e2fs_state; /* file system state */ 85 u_int16_t e2fs_beh; /* behavior on errors */ 86 u_int16_t e2fs_minrev; /* minor revision level */ 87 u_int32_t e2fs_lastfsck; /* time of last fsck */ 88 u_int32_t e2fs_fsckintv; /* max time between fscks */ 89 u_int32_t e2fs_creator; /* creator OS */ 90 u_int32_t e2fs_rev; /* revision level */ 91 u_int16_t e2fs_ruid; /* default uid for reserved blocks */ 92 u_int16_t e2fs_rgid; /* default gid for reserved blocks */ 93 /* EXT2_DYNAMIC_REV superblocks */ 94 u_int32_t e2fs_first_ino; /* first non-reserved inode */ 95 u_int16_t e2fs_inode_size; /* size of inode structure */ 96 u_int16_t e2fs_block_group_nr; /* block grp number of this sblk*/ 97 u_int32_t e2fs_features_compat; /* compatible feature set */ 98 u_int32_t e2fs_features_incompat; /* incompatible feature set */ 99 u_int32_t e2fs_features_rocompat; /* RO-compatible feature set */ 100 u_int8_t e2fs_uuid[16]; /* 128-bit uuid for volume */ 101 char e2fs_vname[16]; /* volume name */ 102 char e2fs_fsmnt[64]; /* name mounted on */ 103 u_int32_t e2fs_algo; /* For comcate for dir */ 104 u_int16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */ 105 u_int32_t reserved2[204]; 106 }; 107 108 109 /* 110 * In-Memory Superblock 111 */ 112 113 struct m_ext2fs { 114 struct ext2fs * e2fs; 115 char e2fs_fsmnt[MAXMNTLEN];/* name mounted on */ 116 char e2fs_ronly; /* mounted read-only flag */ 117 char e2fs_fmod; /* super block modified flag */ 118 uint32_t e2fs_bsize; /* Block size */ 119 uint32_t e2fs_bshift; /* calc of logical block no */ 120 int32_t e2fs_bmask; /* calc of block offset */ 121 int32_t e2fs_bpg; /* Number of blocks per group */ 122 int64_t e2fs_qbmask; /* = s_blocksize -1 */ 123 uint32_t e2fs_fsbtodb; /* Shift to get disk block */ 124 uint32_t e2fs_ipg; /* Number of inodes per group */ 125 uint32_t e2fs_ipb; /* Number of inodes per block */ 126 uint32_t e2fs_itpg; /* Number of inode table per group */ 127 uint32_t e2fs_fsize; /* Size of fragments per block */ 128 uint32_t e2fs_fpb; /* Number of fragments per block */ 129 uint32_t e2fs_fpg; /* Number of fragments per group */ 130 uint32_t e2fs_dbpg; /* Number of descriptor blocks per group */ 131 uint32_t e2fs_descpb; /* Number of group descriptors per block */ 132 uint32_t e2fs_gdbcount; /* Number of group descriptors */ 133 uint32_t e2fs_gcount; /* Number of groups */ 134 uint32_t e2fs_first_inode;/* First inode on fs */ 135 int32_t e2fs_isize; /* Size of inode */ 136 uint32_t e2fs_mount_opt; 137 uint32_t e2fs_blocksize_bits; 138 uint32_t e2fs_total_dir; /* Total number of directories */ 139 uint8_t *e2fs_contigdirs; /* (u) # of contig. allocated dirs */ 140 char e2fs_wasvalid; /* valid at mount time */ 141 off_t e2fs_maxfilesize; 142 struct ext2_gd *e2fs_gd; /* Group Descriptors */ 143 }; 144 145 /* 146 * The second extended file system version 147 */ 148 #define E2FS_DATE "95/08/09" 149 #define E2FS_VERSION "0.5b" 150 151 /* 152 * The second extended file system magic number 153 */ 154 #define E2FS_MAGIC 0xEF53 155 156 /* 157 * Revision levels 158 */ 159 #define E2FS_REV0 0 /* The good old (original) format */ 160 #define E2FS_REV1 1 /* V2 format w/ dynamic inode sizes */ 161 162 #define E2FS_CURRENT_REV E2FS_REV0 163 #define E2FS_MAX_SUPP_REV E2FS_REV1 164 165 #define E2FS_REV0_INODE_SIZE 128 166 167 /* 168 * compatible/incompatible features 169 */ 170 #define EXT2F_COMPAT_PREALLOC 0x0001 171 #define EXT2F_COMPAT_HASJOURNAL 0x0004 172 #define EXT2F_COMPAT_RESIZE 0x0010 173 174 #define EXT2F_ROCOMPAT_SPARSESUPER 0x0001 175 #define EXT2F_ROCOMPAT_LARGEFILE 0x0002 176 #define EXT2F_ROCOMPAT_BTREE_DIR 0x0004 177 178 #define EXT2F_INCOMPAT_COMP 0x0001 179 #define EXT2F_INCOMPAT_FTYPE 0x0002 180 181 /* 182 * Features supported in this implementation 183 * 184 * We support the following REV1 features: 185 * - EXT2F_ROCOMPAT_SPARSESUPER 186 * - EXT2F_ROCOMPAT_LARGEFILE 187 * - EXT2F_INCOMPAT_FTYPE 188 */ 189 #define EXT2F_COMPAT_SUPP 0x0000 190 #define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER \ 191 | EXT2F_ROCOMPAT_LARGEFILE) 192 #define EXT2F_INCOMPAT_SUPP EXT2F_INCOMPAT_FTYPE 193 194 /* Assume that user mode programs are passing in an ext2fs superblock, not 195 * a kernel struct super_block. This will allow us to call the feature-test 196 * macros from user land. */ 197 #define EXT2_SB(sb) (sb) 198 199 /* 200 * Feature set definitions 201 */ 202 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 203 ( EXT2_SB(sb)->e2fs->e2fs_features_compat & htole32(mask) ) 204 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 205 ( EXT2_SB(sb)->e2fs->e2fs_features_rocompat & htole32(mask) ) 206 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 207 ( EXT2_SB(sb)->e2fs->e2fs_features_incompat & htole32(mask) ) 208 209 /* 210 * Definitions of behavior on errors 211 */ 212 #define E2FS_BEH_CONTINUE 1 /* continue operation */ 213 #define E2FS_BEH_READONLY 2 /* remount fs read only */ 214 #define E2FS_BEH_PANIC 3 /* cause panic */ 215 #define E2FS_BEH_DEFAULT E2FS_BEH_CONTINUE 216 217 /* 218 * OS identification 219 */ 220 #define E2FS_OS_LINUX 0 221 #define E2FS_OS_HURD 1 222 #define E2FS_OS_MASIX 2 223 #define E2FS_OS_FREEBSD 3 224 #define E2FS_OS_LITES 4 225 226 /* 227 * File clean flags 228 */ 229 #define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */ 230 #define E2FS_ERRORS 0x0002 /* Errors detected */ 231 232 /* ext2 file system block group descriptor */ 233 234 struct ext2_gd { 235 u_int32_t ext2bgd_b_bitmap; /* blocks bitmap block */ 236 u_int32_t ext2bgd_i_bitmap; /* inodes bitmap block */ 237 u_int32_t ext2bgd_i_tables; /* inodes table block */ 238 u_int16_t ext2bgd_nbfree; /* number of free blocks */ 239 u_int16_t ext2bgd_nifree; /* number of free inodes */ 240 u_int16_t ext2bgd_ndirs; /* number of directories */ 241 u_int16_t reserved; 242 u_int32_t reserved2[3]; 243 }; 244 245 /* EXT2FS metadatas are stored in little-endian byte order. These macros 246 * helps reading these metadatas 247 */ 248 249 #define e2fs_cgload(old, new, size) memcpy((new), (old), (size)); 250 #define e2fs_cgsave(old, new, size) memcpy((new), (old), (size)); 251 252 /* 253 * Macro-instructions used to manage several block sizes 254 */ 255 #define EXT2_MIN_BLOCK_SIZE 1024 256 #define EXT2_MAX_BLOCK_SIZE 4096 257 #define EXT2_MIN_BLOCK_LOG_SIZE 10 258 #if defined(_KERNEL) 259 # define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize) 260 #else 261 # define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->e2fs_log_bsize) 262 #endif 263 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (uint32_t)) 264 #if defined(_KERNEL) 265 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->e2fs_blocksize_bits) 266 #else 267 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->e2fs_log_bsize + 10) 268 #endif 269 #if defined(_KERNEL) 270 #define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits) 271 #define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize) 272 #define EXT2_FIRST_INO(s) (EXT2_SB(s)->e2fs_first_inode) 273 #else 274 #define EXT2_INODE_SIZE(s) (((s)->s_rev_level == E2FS_REV0) ? \ 275 E2FS_REV0 : (s)->s_inode_size) 276 #define EXT2_FIRST_INO(s) (((s)->s_rev_level == E2FS_REV0) ? \ 277 E2FS_REV0 : (s)->e2fs_first_ino) 278 #endif 279 280 /* 281 * Macro-instructions used to manage fragments 282 */ 283 #define EXT2_MIN_FRAG_SIZE 1024 284 #define EXT2_MAX_FRAG_SIZE 4096 285 #define EXT2_MIN_FRAG_LOG_SIZE 10 286 #if defined(_KERNEL) 287 # define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize) 288 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb) 289 #else 290 # define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->e2fs_log_fsize) 291 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s)) 292 #endif 293 294 /* 295 * Macro-instructions used to manage group descriptors 296 */ 297 #if defined(_KERNEL) 298 # define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg) 299 # define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->e2fs_descpb) 300 # define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits) 301 #else 302 # define EXT2_BLOCKS_PER_GROUP(s) ((s)->e2fs_bpg) 303 # define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_gd)) 304 305 #endif 306 307 #endif /* !_FS_EXT2FS_EXT2FS_H_ */ 308