1 /* 2 * linux/fs/sysv/inode.c 3 * 4 * minix/inode.c 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 * 7 * xenix/inode.c 8 * Copyright (C) 1992 Doug Evans 9 * 10 * coh/inode.c 11 * Copyright (C) 1993 Pascal Haible, Bruno Haible 12 * 13 * sysv/inode.c 14 * Copyright (C) 1993 Paul B. Monday 15 * 16 * sysv/inode.c 17 * Copyright (C) 1993 Bruno Haible 18 * Copyright (C) 1997, 1998 Krzysztof G. Baranowski 19 * 20 * This file contains code for allocating/freeing inodes and for read/writing 21 * the superblock. 22 */ 23 24 #include <linux/smp_lock.h> 25 #include <linux/highuid.h> 26 #include <linux/slab.h> 27 #include <linux/init.h> 28 #include <linux/buffer_head.h> 29 #include <linux/vfs.h> 30 #include <asm/byteorder.h> 31 #include "sysv.h" 32 33 /* This is only called on sync() and umount(), when s_dirt=1. */ 34 static void sysv_write_super(struct super_block *sb) 35 { 36 struct sysv_sb_info *sbi = SYSV_SB(sb); 37 unsigned long time = get_seconds(), old_time; 38 39 lock_kernel(); 40 if (sb->s_flags & MS_RDONLY) 41 goto clean; 42 43 /* 44 * If we are going to write out the super block, 45 * then attach current time stamp. 46 * But if the filesystem was marked clean, keep it clean. 47 */ 48 old_time = fs32_to_cpu(sbi, *sbi->s_sb_time); 49 if (sbi->s_type == FSTYPE_SYSV4) { 50 if (*sbi->s_sb_state == cpu_to_fs32(sbi, 0x7c269d38 - old_time)) 51 *sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38 - time); 52 *sbi->s_sb_time = cpu_to_fs32(sbi, time); 53 mark_buffer_dirty(sbi->s_bh2); 54 } 55 clean: 56 sb->s_dirt = 0; 57 unlock_kernel(); 58 } 59 60 static int sysv_remount(struct super_block *sb, int *flags, char *data) 61 { 62 struct sysv_sb_info *sbi = SYSV_SB(sb); 63 if (sbi->s_forced_ro) 64 *flags |= MS_RDONLY; 65 if (!(*flags & MS_RDONLY)) 66 sb->s_dirt = 1; 67 return 0; 68 } 69 70 static void sysv_put_super(struct super_block *sb) 71 { 72 struct sysv_sb_info *sbi = SYSV_SB(sb); 73 74 if (!(sb->s_flags & MS_RDONLY)) { 75 /* XXX ext2 also updates the state here */ 76 mark_buffer_dirty(sbi->s_bh1); 77 if (sbi->s_bh1 != sbi->s_bh2) 78 mark_buffer_dirty(sbi->s_bh2); 79 } 80 81 brelse(sbi->s_bh1); 82 if (sbi->s_bh1 != sbi->s_bh2) 83 brelse(sbi->s_bh2); 84 85 kfree(sbi); 86 } 87 88 static int sysv_statfs(struct super_block *sb, struct kstatfs *buf) 89 { 90 struct sysv_sb_info *sbi = SYSV_SB(sb); 91 92 buf->f_type = sb->s_magic; 93 buf->f_bsize = sb->s_blocksize; 94 buf->f_blocks = sbi->s_ndatazones; 95 buf->f_bavail = buf->f_bfree = sysv_count_free_blocks(sb); 96 buf->f_files = sbi->s_ninodes; 97 buf->f_ffree = sysv_count_free_inodes(sb); 98 buf->f_namelen = SYSV_NAMELEN; 99 return 0; 100 } 101 102 /* 103 * NXI <-> N0XI for PDP, XIN <-> XIN0 for le32, NIX <-> 0NIX for be32 104 */ 105 static inline void read3byte(struct sysv_sb_info *sbi, 106 unsigned char * from, unsigned char * to) 107 { 108 if (sbi->s_bytesex == BYTESEX_PDP) { 109 to[0] = from[0]; 110 to[1] = 0; 111 to[2] = from[1]; 112 to[3] = from[2]; 113 } else if (sbi->s_bytesex == BYTESEX_LE) { 114 to[0] = from[0]; 115 to[1] = from[1]; 116 to[2] = from[2]; 117 to[3] = 0; 118 } else { 119 to[0] = 0; 120 to[1] = from[0]; 121 to[2] = from[1]; 122 to[3] = from[2]; 123 } 124 } 125 126 static inline void write3byte(struct sysv_sb_info *sbi, 127 unsigned char * from, unsigned char * to) 128 { 129 if (sbi->s_bytesex == BYTESEX_PDP) { 130 to[0] = from[0]; 131 to[1] = from[2]; 132 to[2] = from[3]; 133 } else if (sbi->s_bytesex == BYTESEX_LE) { 134 to[0] = from[0]; 135 to[1] = from[1]; 136 to[2] = from[2]; 137 } else { 138 to[0] = from[1]; 139 to[1] = from[2]; 140 to[2] = from[3]; 141 } 142 } 143 144 static struct inode_operations sysv_symlink_inode_operations = { 145 .readlink = generic_readlink, 146 .follow_link = page_follow_link_light, 147 .put_link = page_put_link, 148 .getattr = sysv_getattr, 149 }; 150 151 void sysv_set_inode(struct inode *inode, dev_t rdev) 152 { 153 if (S_ISREG(inode->i_mode)) { 154 inode->i_op = &sysv_file_inode_operations; 155 inode->i_fop = &sysv_file_operations; 156 inode->i_mapping->a_ops = &sysv_aops; 157 } else if (S_ISDIR(inode->i_mode)) { 158 inode->i_op = &sysv_dir_inode_operations; 159 inode->i_fop = &sysv_dir_operations; 160 inode->i_mapping->a_ops = &sysv_aops; 161 } else if (S_ISLNK(inode->i_mode)) { 162 if (inode->i_blocks) { 163 inode->i_op = &sysv_symlink_inode_operations; 164 inode->i_mapping->a_ops = &sysv_aops; 165 } else 166 inode->i_op = &sysv_fast_symlink_inode_operations; 167 } else 168 init_special_inode(inode, inode->i_mode, rdev); 169 } 170 171 static void sysv_read_inode(struct inode *inode) 172 { 173 struct super_block * sb = inode->i_sb; 174 struct sysv_sb_info * sbi = SYSV_SB(sb); 175 struct buffer_head * bh; 176 struct sysv_inode * raw_inode; 177 struct sysv_inode_info * si; 178 unsigned int block, ino = inode->i_ino; 179 180 if (!ino || ino > sbi->s_ninodes) { 181 printk("Bad inode number on dev %s: %d is out of range\n", 182 inode->i_sb->s_id, ino); 183 goto bad_inode; 184 } 185 raw_inode = sysv_raw_inode(sb, ino, &bh); 186 if (!raw_inode) { 187 printk("Major problem: unable to read inode from dev %s\n", 188 inode->i_sb->s_id); 189 goto bad_inode; 190 } 191 /* SystemV FS: kludge permissions if ino==SYSV_ROOT_INO ?? */ 192 inode->i_mode = fs16_to_cpu(sbi, raw_inode->i_mode); 193 inode->i_uid = (uid_t)fs16_to_cpu(sbi, raw_inode->i_uid); 194 inode->i_gid = (gid_t)fs16_to_cpu(sbi, raw_inode->i_gid); 195 inode->i_nlink = fs16_to_cpu(sbi, raw_inode->i_nlink); 196 inode->i_size = fs32_to_cpu(sbi, raw_inode->i_size); 197 inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_atime); 198 inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_mtime); 199 inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_ctime); 200 inode->i_ctime.tv_nsec = 0; 201 inode->i_atime.tv_nsec = 0; 202 inode->i_mtime.tv_nsec = 0; 203 inode->i_blocks = inode->i_blksize = 0; 204 205 si = SYSV_I(inode); 206 for (block = 0; block < 10+1+1+1; block++) 207 read3byte(sbi, &raw_inode->i_data[3*block], 208 (u8 *)&si->i_data[block]); 209 brelse(bh); 210 si->i_dir_start_lookup = 0; 211 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 212 sysv_set_inode(inode, 213 old_decode_dev(fs32_to_cpu(sbi, si->i_data[0]))); 214 else 215 sysv_set_inode(inode, 0); 216 return; 217 218 bad_inode: 219 make_bad_inode(inode); 220 return; 221 } 222 223 static struct buffer_head * sysv_update_inode(struct inode * inode) 224 { 225 struct super_block * sb = inode->i_sb; 226 struct sysv_sb_info * sbi = SYSV_SB(sb); 227 struct buffer_head * bh; 228 struct sysv_inode * raw_inode; 229 struct sysv_inode_info * si; 230 unsigned int ino, block; 231 232 ino = inode->i_ino; 233 if (!ino || ino > sbi->s_ninodes) { 234 printk("Bad inode number on dev %s: %d is out of range\n", 235 inode->i_sb->s_id, ino); 236 return NULL; 237 } 238 raw_inode = sysv_raw_inode(sb, ino, &bh); 239 if (!raw_inode) { 240 printk("unable to read i-node block\n"); 241 return NULL; 242 } 243 244 raw_inode->i_mode = cpu_to_fs16(sbi, inode->i_mode); 245 raw_inode->i_uid = cpu_to_fs16(sbi, fs_high2lowuid(inode->i_uid)); 246 raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(inode->i_gid)); 247 raw_inode->i_nlink = cpu_to_fs16(sbi, inode->i_nlink); 248 raw_inode->i_size = cpu_to_fs32(sbi, inode->i_size); 249 raw_inode->i_atime = cpu_to_fs32(sbi, inode->i_atime.tv_sec); 250 raw_inode->i_mtime = cpu_to_fs32(sbi, inode->i_mtime.tv_sec); 251 raw_inode->i_ctime = cpu_to_fs32(sbi, inode->i_ctime.tv_sec); 252 253 si = SYSV_I(inode); 254 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 255 si->i_data[0] = cpu_to_fs32(sbi, old_encode_dev(inode->i_rdev)); 256 for (block = 0; block < 10+1+1+1; block++) 257 write3byte(sbi, (u8 *)&si->i_data[block], 258 &raw_inode->i_data[3*block]); 259 mark_buffer_dirty(bh); 260 return bh; 261 } 262 263 int sysv_write_inode(struct inode * inode, int wait) 264 { 265 struct buffer_head *bh; 266 lock_kernel(); 267 bh = sysv_update_inode(inode); 268 brelse(bh); 269 unlock_kernel(); 270 return 0; 271 } 272 273 int sysv_sync_inode(struct inode * inode) 274 { 275 int err = 0; 276 struct buffer_head *bh; 277 278 bh = sysv_update_inode(inode); 279 if (bh && buffer_dirty(bh)) { 280 sync_dirty_buffer(bh); 281 if (buffer_req(bh) && !buffer_uptodate(bh)) { 282 printk ("IO error syncing sysv inode [%s:%08lx]\n", 283 inode->i_sb->s_id, inode->i_ino); 284 err = -1; 285 } 286 } 287 else if (!bh) 288 err = -1; 289 brelse (bh); 290 return err; 291 } 292 293 static void sysv_delete_inode(struct inode *inode) 294 { 295 truncate_inode_pages(&inode->i_data, 0); 296 inode->i_size = 0; 297 sysv_truncate(inode); 298 lock_kernel(); 299 sysv_free_inode(inode); 300 unlock_kernel(); 301 } 302 303 static kmem_cache_t *sysv_inode_cachep; 304 305 static struct inode *sysv_alloc_inode(struct super_block *sb) 306 { 307 struct sysv_inode_info *si; 308 309 si = kmem_cache_alloc(sysv_inode_cachep, SLAB_KERNEL); 310 if (!si) 311 return NULL; 312 return &si->vfs_inode; 313 } 314 315 static void sysv_destroy_inode(struct inode *inode) 316 { 317 kmem_cache_free(sysv_inode_cachep, SYSV_I(inode)); 318 } 319 320 static void init_once(void *p, kmem_cache_t *cachep, unsigned long flags) 321 { 322 struct sysv_inode_info *si = (struct sysv_inode_info *)p; 323 324 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == 325 SLAB_CTOR_CONSTRUCTOR) 326 inode_init_once(&si->vfs_inode); 327 } 328 329 struct super_operations sysv_sops = { 330 .alloc_inode = sysv_alloc_inode, 331 .destroy_inode = sysv_destroy_inode, 332 .read_inode = sysv_read_inode, 333 .write_inode = sysv_write_inode, 334 .delete_inode = sysv_delete_inode, 335 .put_super = sysv_put_super, 336 .write_super = sysv_write_super, 337 .remount_fs = sysv_remount, 338 .statfs = sysv_statfs, 339 }; 340 341 int __init sysv_init_icache(void) 342 { 343 sysv_inode_cachep = kmem_cache_create("sysv_inode_cache", 344 sizeof(struct sysv_inode_info), 0, 345 SLAB_RECLAIM_ACCOUNT, 346 init_once, NULL); 347 if (!sysv_inode_cachep) 348 return -ENOMEM; 349 return 0; 350 } 351 352 void sysv_destroy_icache(void) 353 { 354 kmem_cache_destroy(sysv_inode_cachep); 355 } 356