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/highuid.h> 25 #include <linux/slab.h> 26 #include <linux/init.h> 27 #include <linux/buffer_head.h> 28 #include <linux/vfs.h> 29 #include <linux/namei.h> 30 #include <asm/byteorder.h> 31 #include "sysv.h" 32 33 static int sysv_sync_fs(struct super_block *sb, int wait) 34 { 35 struct sysv_sb_info *sbi = SYSV_SB(sb); 36 unsigned long time = get_seconds(), old_time; 37 38 lock_super(sb); 39 40 /* 41 * If we are going to write out the super block, 42 * then attach current time stamp. 43 * But if the filesystem was marked clean, keep it clean. 44 */ 45 old_time = fs32_to_cpu(sbi, *sbi->s_sb_time); 46 if (sbi->s_type == FSTYPE_SYSV4) { 47 if (*sbi->s_sb_state == cpu_to_fs32(sbi, 0x7c269d38 - old_time)) 48 *sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38 - time); 49 *sbi->s_sb_time = cpu_to_fs32(sbi, time); 50 mark_buffer_dirty(sbi->s_bh2); 51 } 52 53 unlock_super(sb); 54 55 return 0; 56 } 57 58 static void sysv_write_super(struct super_block *sb) 59 { 60 if (!(sb->s_flags & MS_RDONLY)) 61 sysv_sync_fs(sb, 1); 62 else 63 sb->s_dirt = 0; 64 } 65 66 static int sysv_remount(struct super_block *sb, int *flags, char *data) 67 { 68 struct sysv_sb_info *sbi = SYSV_SB(sb); 69 lock_super(sb); 70 if (sbi->s_forced_ro) 71 *flags |= MS_RDONLY; 72 if (!(*flags & MS_RDONLY)) 73 sb->s_dirt = 1; 74 unlock_super(sb); 75 return 0; 76 } 77 78 static void sysv_put_super(struct super_block *sb) 79 { 80 struct sysv_sb_info *sbi = SYSV_SB(sb); 81 82 if (sb->s_dirt) 83 sysv_write_super(sb); 84 85 if (!(sb->s_flags & MS_RDONLY)) { 86 /* XXX ext2 also updates the state here */ 87 mark_buffer_dirty(sbi->s_bh1); 88 if (sbi->s_bh1 != sbi->s_bh2) 89 mark_buffer_dirty(sbi->s_bh2); 90 } 91 92 brelse(sbi->s_bh1); 93 if (sbi->s_bh1 != sbi->s_bh2) 94 brelse(sbi->s_bh2); 95 96 kfree(sbi); 97 } 98 99 static int sysv_statfs(struct dentry *dentry, struct kstatfs *buf) 100 { 101 struct super_block *sb = dentry->d_sb; 102 struct sysv_sb_info *sbi = SYSV_SB(sb); 103 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 104 105 buf->f_type = sb->s_magic; 106 buf->f_bsize = sb->s_blocksize; 107 buf->f_blocks = sbi->s_ndatazones; 108 buf->f_bavail = buf->f_bfree = sysv_count_free_blocks(sb); 109 buf->f_files = sbi->s_ninodes; 110 buf->f_ffree = sysv_count_free_inodes(sb); 111 buf->f_namelen = SYSV_NAMELEN; 112 buf->f_fsid.val[0] = (u32)id; 113 buf->f_fsid.val[1] = (u32)(id >> 32); 114 return 0; 115 } 116 117 /* 118 * NXI <-> N0XI for PDP, XIN <-> XIN0 for le32, NIX <-> 0NIX for be32 119 */ 120 static inline void read3byte(struct sysv_sb_info *sbi, 121 unsigned char * from, unsigned char * to) 122 { 123 if (sbi->s_bytesex == BYTESEX_PDP) { 124 to[0] = from[0]; 125 to[1] = 0; 126 to[2] = from[1]; 127 to[3] = from[2]; 128 } else if (sbi->s_bytesex == BYTESEX_LE) { 129 to[0] = from[0]; 130 to[1] = from[1]; 131 to[2] = from[2]; 132 to[3] = 0; 133 } else { 134 to[0] = 0; 135 to[1] = from[0]; 136 to[2] = from[1]; 137 to[3] = from[2]; 138 } 139 } 140 141 static inline void write3byte(struct sysv_sb_info *sbi, 142 unsigned char * from, unsigned char * to) 143 { 144 if (sbi->s_bytesex == BYTESEX_PDP) { 145 to[0] = from[0]; 146 to[1] = from[2]; 147 to[2] = from[3]; 148 } else if (sbi->s_bytesex == BYTESEX_LE) { 149 to[0] = from[0]; 150 to[1] = from[1]; 151 to[2] = from[2]; 152 } else { 153 to[0] = from[1]; 154 to[1] = from[2]; 155 to[2] = from[3]; 156 } 157 } 158 159 static const struct inode_operations sysv_symlink_inode_operations = { 160 .readlink = generic_readlink, 161 .follow_link = page_follow_link_light, 162 .put_link = page_put_link, 163 .getattr = sysv_getattr, 164 }; 165 166 void sysv_set_inode(struct inode *inode, dev_t rdev) 167 { 168 if (S_ISREG(inode->i_mode)) { 169 inode->i_op = &sysv_file_inode_operations; 170 inode->i_fop = &sysv_file_operations; 171 inode->i_mapping->a_ops = &sysv_aops; 172 } else if (S_ISDIR(inode->i_mode)) { 173 inode->i_op = &sysv_dir_inode_operations; 174 inode->i_fop = &sysv_dir_operations; 175 inode->i_mapping->a_ops = &sysv_aops; 176 } else if (S_ISLNK(inode->i_mode)) { 177 if (inode->i_blocks) { 178 inode->i_op = &sysv_symlink_inode_operations; 179 inode->i_mapping->a_ops = &sysv_aops; 180 } else { 181 inode->i_op = &sysv_fast_symlink_inode_operations; 182 nd_terminate_link(SYSV_I(inode)->i_data, inode->i_size, 183 sizeof(SYSV_I(inode)->i_data) - 1); 184 } 185 } else 186 init_special_inode(inode, inode->i_mode, rdev); 187 } 188 189 struct inode *sysv_iget(struct super_block *sb, unsigned int ino) 190 { 191 struct sysv_sb_info * sbi = SYSV_SB(sb); 192 struct buffer_head * bh; 193 struct sysv_inode * raw_inode; 194 struct sysv_inode_info * si; 195 struct inode *inode; 196 unsigned int block; 197 198 if (!ino || ino > sbi->s_ninodes) { 199 printk("Bad inode number on dev %s: %d is out of range\n", 200 sb->s_id, ino); 201 return ERR_PTR(-EIO); 202 } 203 204 inode = iget_locked(sb, ino); 205 if (!inode) 206 return ERR_PTR(-ENOMEM); 207 if (!(inode->i_state & I_NEW)) 208 return inode; 209 210 raw_inode = sysv_raw_inode(sb, ino, &bh); 211 if (!raw_inode) { 212 printk("Major problem: unable to read inode from dev %s\n", 213 inode->i_sb->s_id); 214 goto bad_inode; 215 } 216 /* SystemV FS: kludge permissions if ino==SYSV_ROOT_INO ?? */ 217 inode->i_mode = fs16_to_cpu(sbi, raw_inode->i_mode); 218 inode->i_uid = (uid_t)fs16_to_cpu(sbi, raw_inode->i_uid); 219 inode->i_gid = (gid_t)fs16_to_cpu(sbi, raw_inode->i_gid); 220 inode->i_nlink = fs16_to_cpu(sbi, raw_inode->i_nlink); 221 inode->i_size = fs32_to_cpu(sbi, raw_inode->i_size); 222 inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_atime); 223 inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_mtime); 224 inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_ctime); 225 inode->i_ctime.tv_nsec = 0; 226 inode->i_atime.tv_nsec = 0; 227 inode->i_mtime.tv_nsec = 0; 228 inode->i_blocks = 0; 229 230 si = SYSV_I(inode); 231 for (block = 0; block < 10+1+1+1; block++) 232 read3byte(sbi, &raw_inode->i_data[3*block], 233 (u8 *)&si->i_data[block]); 234 brelse(bh); 235 si->i_dir_start_lookup = 0; 236 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 237 sysv_set_inode(inode, 238 old_decode_dev(fs32_to_cpu(sbi, si->i_data[0]))); 239 else 240 sysv_set_inode(inode, 0); 241 unlock_new_inode(inode); 242 return inode; 243 244 bad_inode: 245 iget_failed(inode); 246 return ERR_PTR(-EIO); 247 } 248 249 int sysv_write_inode(struct inode *inode, int wait) 250 { 251 struct super_block * sb = inode->i_sb; 252 struct sysv_sb_info * sbi = SYSV_SB(sb); 253 struct buffer_head * bh; 254 struct sysv_inode * raw_inode; 255 struct sysv_inode_info * si; 256 unsigned int ino, block; 257 int err = 0; 258 259 ino = inode->i_ino; 260 if (!ino || ino > sbi->s_ninodes) { 261 printk("Bad inode number on dev %s: %d is out of range\n", 262 inode->i_sb->s_id, ino); 263 return -EIO; 264 } 265 raw_inode = sysv_raw_inode(sb, ino, &bh); 266 if (!raw_inode) { 267 printk("unable to read i-node block\n"); 268 return -EIO; 269 } 270 271 raw_inode->i_mode = cpu_to_fs16(sbi, inode->i_mode); 272 raw_inode->i_uid = cpu_to_fs16(sbi, fs_high2lowuid(inode->i_uid)); 273 raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(inode->i_gid)); 274 raw_inode->i_nlink = cpu_to_fs16(sbi, inode->i_nlink); 275 raw_inode->i_size = cpu_to_fs32(sbi, inode->i_size); 276 raw_inode->i_atime = cpu_to_fs32(sbi, inode->i_atime.tv_sec); 277 raw_inode->i_mtime = cpu_to_fs32(sbi, inode->i_mtime.tv_sec); 278 raw_inode->i_ctime = cpu_to_fs32(sbi, inode->i_ctime.tv_sec); 279 280 si = SYSV_I(inode); 281 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 282 si->i_data[0] = cpu_to_fs32(sbi, old_encode_dev(inode->i_rdev)); 283 for (block = 0; block < 10+1+1+1; block++) 284 write3byte(sbi, (u8 *)&si->i_data[block], 285 &raw_inode->i_data[3*block]); 286 mark_buffer_dirty(bh); 287 if (wait) { 288 sync_dirty_buffer(bh); 289 if (buffer_req(bh) && !buffer_uptodate(bh)) { 290 printk ("IO error syncing sysv inode [%s:%08x]\n", 291 sb->s_id, ino); 292 err = -EIO; 293 } 294 } 295 brelse(bh); 296 return 0; 297 } 298 299 int sysv_sync_inode(struct inode *inode) 300 { 301 return sysv_write_inode(inode, 1); 302 } 303 304 static void sysv_delete_inode(struct inode *inode) 305 { 306 truncate_inode_pages(&inode->i_data, 0); 307 inode->i_size = 0; 308 sysv_truncate(inode); 309 sysv_free_inode(inode); 310 } 311 312 static struct kmem_cache *sysv_inode_cachep; 313 314 static struct inode *sysv_alloc_inode(struct super_block *sb) 315 { 316 struct sysv_inode_info *si; 317 318 si = kmem_cache_alloc(sysv_inode_cachep, GFP_KERNEL); 319 if (!si) 320 return NULL; 321 return &si->vfs_inode; 322 } 323 324 static void sysv_destroy_inode(struct inode *inode) 325 { 326 kmem_cache_free(sysv_inode_cachep, SYSV_I(inode)); 327 } 328 329 static void init_once(void *p) 330 { 331 struct sysv_inode_info *si = (struct sysv_inode_info *)p; 332 333 inode_init_once(&si->vfs_inode); 334 } 335 336 const struct super_operations sysv_sops = { 337 .alloc_inode = sysv_alloc_inode, 338 .destroy_inode = sysv_destroy_inode, 339 .write_inode = sysv_write_inode, 340 .delete_inode = sysv_delete_inode, 341 .put_super = sysv_put_super, 342 .write_super = sysv_write_super, 343 .sync_fs = sysv_sync_fs, 344 .remount_fs = sysv_remount, 345 .statfs = sysv_statfs, 346 }; 347 348 int __init sysv_init_icache(void) 349 { 350 sysv_inode_cachep = kmem_cache_create("sysv_inode_cache", 351 sizeof(struct sysv_inode_info), 0, 352 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, 353 init_once); 354 if (!sysv_inode_cachep) 355 return -ENOMEM; 356 return 0; 357 } 358 359 void sysv_destroy_icache(void) 360 { 361 kmem_cache_destroy(sysv_inode_cachep); 362 } 363