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 <linux/namei.h> 31 #include <asm/byteorder.h> 32 #include "sysv.h" 33 34 /* This is only called on sync() and umount(), when s_dirt=1. */ 35 static void sysv_write_super(struct super_block *sb) 36 { 37 struct sysv_sb_info *sbi = SYSV_SB(sb); 38 unsigned long time = get_seconds(), old_time; 39 40 lock_kernel(); 41 if (sb->s_flags & MS_RDONLY) 42 goto clean; 43 44 /* 45 * If we are going to write out the super block, 46 * then attach current time stamp. 47 * But if the filesystem was marked clean, keep it clean. 48 */ 49 old_time = fs32_to_cpu(sbi, *sbi->s_sb_time); 50 if (sbi->s_type == FSTYPE_SYSV4) { 51 if (*sbi->s_sb_state == cpu_to_fs32(sbi, 0x7c269d38 - old_time)) 52 *sbi->s_sb_state = cpu_to_fs32(sbi, 0x7c269d38 - time); 53 *sbi->s_sb_time = cpu_to_fs32(sbi, time); 54 mark_buffer_dirty(sbi->s_bh2); 55 } 56 clean: 57 sb->s_dirt = 0; 58 unlock_kernel(); 59 } 60 61 static int sysv_remount(struct super_block *sb, int *flags, char *data) 62 { 63 struct sysv_sb_info *sbi = SYSV_SB(sb); 64 if (sbi->s_forced_ro) 65 *flags |= MS_RDONLY; 66 if (!(*flags & MS_RDONLY)) 67 sb->s_dirt = 1; 68 return 0; 69 } 70 71 static void sysv_put_super(struct super_block *sb) 72 { 73 struct sysv_sb_info *sbi = SYSV_SB(sb); 74 75 if (!(sb->s_flags & MS_RDONLY)) { 76 /* XXX ext2 also updates the state here */ 77 mark_buffer_dirty(sbi->s_bh1); 78 if (sbi->s_bh1 != sbi->s_bh2) 79 mark_buffer_dirty(sbi->s_bh2); 80 } 81 82 brelse(sbi->s_bh1); 83 if (sbi->s_bh1 != sbi->s_bh2) 84 brelse(sbi->s_bh2); 85 86 kfree(sbi); 87 } 88 89 static int sysv_statfs(struct dentry *dentry, struct kstatfs *buf) 90 { 91 struct super_block *sb = dentry->d_sb; 92 struct sysv_sb_info *sbi = SYSV_SB(sb); 93 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 94 95 buf->f_type = sb->s_magic; 96 buf->f_bsize = sb->s_blocksize; 97 buf->f_blocks = sbi->s_ndatazones; 98 buf->f_bavail = buf->f_bfree = sysv_count_free_blocks(sb); 99 buf->f_files = sbi->s_ninodes; 100 buf->f_ffree = sysv_count_free_inodes(sb); 101 buf->f_namelen = SYSV_NAMELEN; 102 buf->f_fsid.val[0] = (u32)id; 103 buf->f_fsid.val[1] = (u32)(id >> 32); 104 return 0; 105 } 106 107 /* 108 * NXI <-> N0XI for PDP, XIN <-> XIN0 for le32, NIX <-> 0NIX for be32 109 */ 110 static inline void read3byte(struct sysv_sb_info *sbi, 111 unsigned char * from, unsigned char * to) 112 { 113 if (sbi->s_bytesex == BYTESEX_PDP) { 114 to[0] = from[0]; 115 to[1] = 0; 116 to[2] = from[1]; 117 to[3] = from[2]; 118 } else if (sbi->s_bytesex == BYTESEX_LE) { 119 to[0] = from[0]; 120 to[1] = from[1]; 121 to[2] = from[2]; 122 to[3] = 0; 123 } else { 124 to[0] = 0; 125 to[1] = from[0]; 126 to[2] = from[1]; 127 to[3] = from[2]; 128 } 129 } 130 131 static inline void write3byte(struct sysv_sb_info *sbi, 132 unsigned char * from, unsigned char * to) 133 { 134 if (sbi->s_bytesex == BYTESEX_PDP) { 135 to[0] = from[0]; 136 to[1] = from[2]; 137 to[2] = from[3]; 138 } else if (sbi->s_bytesex == BYTESEX_LE) { 139 to[0] = from[0]; 140 to[1] = from[1]; 141 to[2] = from[2]; 142 } else { 143 to[0] = from[1]; 144 to[1] = from[2]; 145 to[2] = from[3]; 146 } 147 } 148 149 static const struct inode_operations sysv_symlink_inode_operations = { 150 .readlink = generic_readlink, 151 .follow_link = page_follow_link_light, 152 .put_link = page_put_link, 153 .getattr = sysv_getattr, 154 }; 155 156 void sysv_set_inode(struct inode *inode, dev_t rdev) 157 { 158 if (S_ISREG(inode->i_mode)) { 159 inode->i_op = &sysv_file_inode_operations; 160 inode->i_fop = &sysv_file_operations; 161 inode->i_mapping->a_ops = &sysv_aops; 162 } else if (S_ISDIR(inode->i_mode)) { 163 inode->i_op = &sysv_dir_inode_operations; 164 inode->i_fop = &sysv_dir_operations; 165 inode->i_mapping->a_ops = &sysv_aops; 166 } else if (S_ISLNK(inode->i_mode)) { 167 if (inode->i_blocks) { 168 inode->i_op = &sysv_symlink_inode_operations; 169 inode->i_mapping->a_ops = &sysv_aops; 170 } else { 171 inode->i_op = &sysv_fast_symlink_inode_operations; 172 nd_terminate_link(SYSV_I(inode)->i_data, inode->i_size, 173 sizeof(SYSV_I(inode)->i_data) - 1); 174 } 175 } else 176 init_special_inode(inode, inode->i_mode, rdev); 177 } 178 179 struct inode *sysv_iget(struct super_block *sb, unsigned int ino) 180 { 181 struct sysv_sb_info * sbi = SYSV_SB(sb); 182 struct buffer_head * bh; 183 struct sysv_inode * raw_inode; 184 struct sysv_inode_info * si; 185 struct inode *inode; 186 unsigned int block; 187 188 if (!ino || ino > sbi->s_ninodes) { 189 printk("Bad inode number on dev %s: %d is out of range\n", 190 sb->s_id, ino); 191 return ERR_PTR(-EIO); 192 } 193 194 inode = iget_locked(sb, ino); 195 if (!inode) 196 return ERR_PTR(-ENOMEM); 197 if (!(inode->i_state & I_NEW)) 198 return inode; 199 200 raw_inode = sysv_raw_inode(sb, ino, &bh); 201 if (!raw_inode) { 202 printk("Major problem: unable to read inode from dev %s\n", 203 inode->i_sb->s_id); 204 goto bad_inode; 205 } 206 /* SystemV FS: kludge permissions if ino==SYSV_ROOT_INO ?? */ 207 inode->i_mode = fs16_to_cpu(sbi, raw_inode->i_mode); 208 inode->i_uid = (uid_t)fs16_to_cpu(sbi, raw_inode->i_uid); 209 inode->i_gid = (gid_t)fs16_to_cpu(sbi, raw_inode->i_gid); 210 inode->i_nlink = fs16_to_cpu(sbi, raw_inode->i_nlink); 211 inode->i_size = fs32_to_cpu(sbi, raw_inode->i_size); 212 inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_atime); 213 inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_mtime); 214 inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->i_ctime); 215 inode->i_ctime.tv_nsec = 0; 216 inode->i_atime.tv_nsec = 0; 217 inode->i_mtime.tv_nsec = 0; 218 inode->i_blocks = 0; 219 220 si = SYSV_I(inode); 221 for (block = 0; block < 10+1+1+1; block++) 222 read3byte(sbi, &raw_inode->i_data[3*block], 223 (u8 *)&si->i_data[block]); 224 brelse(bh); 225 si->i_dir_start_lookup = 0; 226 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 227 sysv_set_inode(inode, 228 old_decode_dev(fs32_to_cpu(sbi, si->i_data[0]))); 229 else 230 sysv_set_inode(inode, 0); 231 unlock_new_inode(inode); 232 return inode; 233 234 bad_inode: 235 iget_failed(inode); 236 return ERR_PTR(-EIO); 237 } 238 239 static struct buffer_head * sysv_update_inode(struct inode * inode) 240 { 241 struct super_block * sb = inode->i_sb; 242 struct sysv_sb_info * sbi = SYSV_SB(sb); 243 struct buffer_head * bh; 244 struct sysv_inode * raw_inode; 245 struct sysv_inode_info * si; 246 unsigned int ino, block; 247 248 ino = inode->i_ino; 249 if (!ino || ino > sbi->s_ninodes) { 250 printk("Bad inode number on dev %s: %d is out of range\n", 251 inode->i_sb->s_id, ino); 252 return NULL; 253 } 254 raw_inode = sysv_raw_inode(sb, ino, &bh); 255 if (!raw_inode) { 256 printk("unable to read i-node block\n"); 257 return NULL; 258 } 259 260 raw_inode->i_mode = cpu_to_fs16(sbi, inode->i_mode); 261 raw_inode->i_uid = cpu_to_fs16(sbi, fs_high2lowuid(inode->i_uid)); 262 raw_inode->i_gid = cpu_to_fs16(sbi, fs_high2lowgid(inode->i_gid)); 263 raw_inode->i_nlink = cpu_to_fs16(sbi, inode->i_nlink); 264 raw_inode->i_size = cpu_to_fs32(sbi, inode->i_size); 265 raw_inode->i_atime = cpu_to_fs32(sbi, inode->i_atime.tv_sec); 266 raw_inode->i_mtime = cpu_to_fs32(sbi, inode->i_mtime.tv_sec); 267 raw_inode->i_ctime = cpu_to_fs32(sbi, inode->i_ctime.tv_sec); 268 269 si = SYSV_I(inode); 270 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 271 si->i_data[0] = cpu_to_fs32(sbi, old_encode_dev(inode->i_rdev)); 272 for (block = 0; block < 10+1+1+1; block++) 273 write3byte(sbi, (u8 *)&si->i_data[block], 274 &raw_inode->i_data[3*block]); 275 mark_buffer_dirty(bh); 276 return bh; 277 } 278 279 int sysv_write_inode(struct inode * inode, int wait) 280 { 281 struct buffer_head *bh; 282 lock_kernel(); 283 bh = sysv_update_inode(inode); 284 brelse(bh); 285 unlock_kernel(); 286 return 0; 287 } 288 289 int sysv_sync_inode(struct inode * inode) 290 { 291 int err = 0; 292 struct buffer_head *bh; 293 294 bh = sysv_update_inode(inode); 295 if (bh && buffer_dirty(bh)) { 296 sync_dirty_buffer(bh); 297 if (buffer_req(bh) && !buffer_uptodate(bh)) { 298 printk ("IO error syncing sysv inode [%s:%08lx]\n", 299 inode->i_sb->s_id, inode->i_ino); 300 err = -1; 301 } 302 } 303 else if (!bh) 304 err = -1; 305 brelse (bh); 306 return err; 307 } 308 309 static void sysv_delete_inode(struct inode *inode) 310 { 311 truncate_inode_pages(&inode->i_data, 0); 312 inode->i_size = 0; 313 sysv_truncate(inode); 314 lock_kernel(); 315 sysv_free_inode(inode); 316 unlock_kernel(); 317 } 318 319 static struct kmem_cache *sysv_inode_cachep; 320 321 static struct inode *sysv_alloc_inode(struct super_block *sb) 322 { 323 struct sysv_inode_info *si; 324 325 si = kmem_cache_alloc(sysv_inode_cachep, GFP_KERNEL); 326 if (!si) 327 return NULL; 328 return &si->vfs_inode; 329 } 330 331 static void sysv_destroy_inode(struct inode *inode) 332 { 333 kmem_cache_free(sysv_inode_cachep, SYSV_I(inode)); 334 } 335 336 static void init_once(void *p) 337 { 338 struct sysv_inode_info *si = (struct sysv_inode_info *)p; 339 340 inode_init_once(&si->vfs_inode); 341 } 342 343 const struct super_operations sysv_sops = { 344 .alloc_inode = sysv_alloc_inode, 345 .destroy_inode = sysv_destroy_inode, 346 .write_inode = sysv_write_inode, 347 .delete_inode = sysv_delete_inode, 348 .put_super = sysv_put_super, 349 .write_super = sysv_write_super, 350 .remount_fs = sysv_remount, 351 .statfs = sysv_statfs, 352 }; 353 354 int __init sysv_init_icache(void) 355 { 356 sysv_inode_cachep = kmem_cache_create("sysv_inode_cache", 357 sizeof(struct sysv_inode_info), 0, 358 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, 359 init_once); 360 if (!sysv_inode_cachep) 361 return -ENOMEM; 362 return 0; 363 } 364 365 void sysv_destroy_icache(void) 366 { 367 kmem_cache_destroy(sysv_inode_cachep); 368 } 369