1 /* 2 * fs/bfs/inode.c 3 * BFS superblock and inode operations. 4 * Copyright (C) 1999-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk> 5 * From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds. 6 * 7 * Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 2005. 8 */ 9 10 #include <linux/module.h> 11 #include <linux/mm.h> 12 #include <linux/slab.h> 13 #include <linux/init.h> 14 #include <linux/fs.h> 15 #include <linux/smp_lock.h> 16 #include <linux/buffer_head.h> 17 #include <linux/vfs.h> 18 #include <linux/writeback.h> 19 #include <asm/uaccess.h> 20 #include "bfs.h" 21 22 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>"); 23 MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux"); 24 MODULE_LICENSE("GPL"); 25 26 #undef DEBUG 27 28 #ifdef DEBUG 29 #define dprintf(x...) printf(x) 30 #else 31 #define dprintf(x...) 32 #endif 33 34 void dump_imap(const char *prefix, struct super_block *s); 35 36 struct inode *bfs_iget(struct super_block *sb, unsigned long ino) 37 { 38 struct bfs_inode *di; 39 struct inode *inode; 40 struct buffer_head *bh; 41 int block, off; 42 43 inode = iget_locked(sb, ino); 44 if (IS_ERR(inode)) 45 return ERR_PTR(-ENOMEM); 46 if (!(inode->i_state & I_NEW)) 47 return inode; 48 49 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) { 50 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino); 51 goto error; 52 } 53 54 block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 55 bh = sb_bread(inode->i_sb, block); 56 if (!bh) { 57 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, 58 ino); 59 goto error; 60 } 61 62 off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 63 di = (struct bfs_inode *)bh->b_data + off; 64 65 inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode); 66 if (le32_to_cpu(di->i_vtype) == BFS_VDIR) { 67 inode->i_mode |= S_IFDIR; 68 inode->i_op = &bfs_dir_inops; 69 inode->i_fop = &bfs_dir_operations; 70 } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) { 71 inode->i_mode |= S_IFREG; 72 inode->i_op = &bfs_file_inops; 73 inode->i_fop = &bfs_file_operations; 74 inode->i_mapping->a_ops = &bfs_aops; 75 } 76 77 BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock); 78 BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock); 79 BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); 80 inode->i_uid = le32_to_cpu(di->i_uid); 81 inode->i_gid = le32_to_cpu(di->i_gid); 82 inode->i_nlink = le32_to_cpu(di->i_nlink); 83 inode->i_size = BFS_FILESIZE(di); 84 inode->i_blocks = BFS_FILEBLOCKS(di); 85 inode->i_atime.tv_sec = le32_to_cpu(di->i_atime); 86 inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime); 87 inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime); 88 inode->i_atime.tv_nsec = 0; 89 inode->i_mtime.tv_nsec = 0; 90 inode->i_ctime.tv_nsec = 0; 91 92 brelse(bh); 93 unlock_new_inode(inode); 94 return inode; 95 96 error: 97 iget_failed(inode); 98 return ERR_PTR(-EIO); 99 } 100 101 static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p) 102 { 103 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) { 104 printf("Bad inode number %s:%08x\n", sb->s_id, ino); 105 return ERR_PTR(-EIO); 106 } 107 108 ino -= BFS_ROOT_INO; 109 110 *p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK); 111 if (!*p) { 112 printf("Unable to read inode %s:%08x\n", sb->s_id, ino); 113 return ERR_PTR(-EIO); 114 } 115 116 return (struct bfs_inode *)(*p)->b_data + ino % BFS_INODES_PER_BLOCK; 117 } 118 119 static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc) 120 { 121 struct bfs_sb_info *info = BFS_SB(inode->i_sb); 122 unsigned int ino = (u16)inode->i_ino; 123 unsigned long i_sblock; 124 struct bfs_inode *di; 125 struct buffer_head *bh; 126 int err = 0; 127 128 dprintf("ino=%08x\n", ino); 129 130 di = find_inode(inode->i_sb, ino, &bh); 131 if (IS_ERR(di)) 132 return PTR_ERR(di); 133 134 mutex_lock(&info->bfs_lock); 135 136 if (ino == BFS_ROOT_INO) 137 di->i_vtype = cpu_to_le32(BFS_VDIR); 138 else 139 di->i_vtype = cpu_to_le32(BFS_VREG); 140 141 di->i_ino = cpu_to_le16(ino); 142 di->i_mode = cpu_to_le32(inode->i_mode); 143 di->i_uid = cpu_to_le32(inode->i_uid); 144 di->i_gid = cpu_to_le32(inode->i_gid); 145 di->i_nlink = cpu_to_le32(inode->i_nlink); 146 di->i_atime = cpu_to_le32(inode->i_atime.tv_sec); 147 di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 148 di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 149 i_sblock = BFS_I(inode)->i_sblock; 150 di->i_sblock = cpu_to_le32(i_sblock); 151 di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock); 152 di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1); 153 154 mark_buffer_dirty(bh); 155 if (wbc->sync_mode == WB_SYNC_ALL) { 156 sync_dirty_buffer(bh); 157 if (buffer_req(bh) && !buffer_uptodate(bh)) 158 err = -EIO; 159 } 160 brelse(bh); 161 mutex_unlock(&info->bfs_lock); 162 return err; 163 } 164 165 static void bfs_evict_inode(struct inode *inode) 166 { 167 unsigned long ino = inode->i_ino; 168 struct bfs_inode *di; 169 struct buffer_head *bh; 170 struct super_block *s = inode->i_sb; 171 struct bfs_sb_info *info = BFS_SB(s); 172 struct bfs_inode_info *bi = BFS_I(inode); 173 174 dprintf("ino=%08lx\n", ino); 175 176 truncate_inode_pages(&inode->i_data, 0); 177 invalidate_inode_buffers(inode); 178 end_writeback(inode); 179 180 if (inode->i_nlink) 181 return; 182 183 di = find_inode(s, inode->i_ino, &bh); 184 if (IS_ERR(di)) 185 return; 186 187 mutex_lock(&info->bfs_lock); 188 /* clear on-disk inode */ 189 memset(di, 0, sizeof(struct bfs_inode)); 190 mark_buffer_dirty(bh); 191 brelse(bh); 192 193 if (bi->i_dsk_ino) { 194 if (bi->i_sblock) 195 info->si_freeb += bi->i_eblock + 1 - bi->i_sblock; 196 info->si_freei++; 197 clear_bit(ino, info->si_imap); 198 dump_imap("delete_inode", s); 199 } 200 201 /* 202 * If this was the last file, make the previous block 203 * "last block of the last file" even if there is no 204 * real file there, saves us 1 gap. 205 */ 206 if (info->si_lf_eblk == bi->i_eblock) 207 info->si_lf_eblk = bi->i_sblock - 1; 208 mutex_unlock(&info->bfs_lock); 209 } 210 211 static void bfs_put_super(struct super_block *s) 212 { 213 struct bfs_sb_info *info = BFS_SB(s); 214 215 if (!info) 216 return; 217 218 lock_kernel(); 219 220 mutex_destroy(&info->bfs_lock); 221 kfree(info->si_imap); 222 kfree(info); 223 s->s_fs_info = NULL; 224 225 unlock_kernel(); 226 } 227 228 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf) 229 { 230 struct super_block *s = dentry->d_sb; 231 struct bfs_sb_info *info = BFS_SB(s); 232 u64 id = huge_encode_dev(s->s_bdev->bd_dev); 233 buf->f_type = BFS_MAGIC; 234 buf->f_bsize = s->s_blocksize; 235 buf->f_blocks = info->si_blocks; 236 buf->f_bfree = buf->f_bavail = info->si_freeb; 237 buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO; 238 buf->f_ffree = info->si_freei; 239 buf->f_fsid.val[0] = (u32)id; 240 buf->f_fsid.val[1] = (u32)(id >> 32); 241 buf->f_namelen = BFS_NAMELEN; 242 return 0; 243 } 244 245 static struct kmem_cache *bfs_inode_cachep; 246 247 static struct inode *bfs_alloc_inode(struct super_block *sb) 248 { 249 struct bfs_inode_info *bi; 250 bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL); 251 if (!bi) 252 return NULL; 253 return &bi->vfs_inode; 254 } 255 256 static void bfs_destroy_inode(struct inode *inode) 257 { 258 kmem_cache_free(bfs_inode_cachep, BFS_I(inode)); 259 } 260 261 static void init_once(void *foo) 262 { 263 struct bfs_inode_info *bi = foo; 264 265 inode_init_once(&bi->vfs_inode); 266 } 267 268 static int init_inodecache(void) 269 { 270 bfs_inode_cachep = kmem_cache_create("bfs_inode_cache", 271 sizeof(struct bfs_inode_info), 272 0, (SLAB_RECLAIM_ACCOUNT| 273 SLAB_MEM_SPREAD), 274 init_once); 275 if (bfs_inode_cachep == NULL) 276 return -ENOMEM; 277 return 0; 278 } 279 280 static void destroy_inodecache(void) 281 { 282 kmem_cache_destroy(bfs_inode_cachep); 283 } 284 285 static const struct super_operations bfs_sops = { 286 .alloc_inode = bfs_alloc_inode, 287 .destroy_inode = bfs_destroy_inode, 288 .write_inode = bfs_write_inode, 289 .evict_inode = bfs_evict_inode, 290 .put_super = bfs_put_super, 291 .statfs = bfs_statfs, 292 }; 293 294 void dump_imap(const char *prefix, struct super_block *s) 295 { 296 #ifdef DEBUG 297 int i; 298 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL); 299 300 if (!tmpbuf) 301 return; 302 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) { 303 if (i > PAGE_SIZE - 100) break; 304 if (test_bit(i, BFS_SB(s)->si_imap)) 305 strcat(tmpbuf, "1"); 306 else 307 strcat(tmpbuf, "0"); 308 } 309 printf("BFS-fs: %s: lasti=%08lx <%s>\n", 310 prefix, BFS_SB(s)->si_lasti, tmpbuf); 311 free_page((unsigned long)tmpbuf); 312 #endif 313 } 314 315 static int bfs_fill_super(struct super_block *s, void *data, int silent) 316 { 317 struct buffer_head *bh, *sbh; 318 struct bfs_super_block *bfs_sb; 319 struct inode *inode; 320 unsigned i, imap_len; 321 struct bfs_sb_info *info; 322 int ret = -EINVAL; 323 unsigned long i_sblock, i_eblock, i_eoff, s_size; 324 325 info = kzalloc(sizeof(*info), GFP_KERNEL); 326 if (!info) 327 return -ENOMEM; 328 mutex_init(&info->bfs_lock); 329 s->s_fs_info = info; 330 331 sb_set_blocksize(s, BFS_BSIZE); 332 333 sbh = sb_bread(s, 0); 334 if (!sbh) 335 goto out; 336 bfs_sb = (struct bfs_super_block *)sbh->b_data; 337 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) { 338 if (!silent) 339 printf("No BFS filesystem on %s (magic=%08x)\n", 340 s->s_id, le32_to_cpu(bfs_sb->s_magic)); 341 goto out1; 342 } 343 if (BFS_UNCLEAN(bfs_sb, s) && !silent) 344 printf("%s is unclean, continuing\n", s->s_id); 345 346 s->s_magic = BFS_MAGIC; 347 348 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) { 349 printf("Superblock is corrupted\n"); 350 goto out1; 351 } 352 353 info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / 354 sizeof(struct bfs_inode) 355 + BFS_ROOT_INO - 1; 356 imap_len = (info->si_lasti / 8) + 1; 357 info->si_imap = kzalloc(imap_len, GFP_KERNEL); 358 if (!info->si_imap) 359 goto out1; 360 for (i = 0; i < BFS_ROOT_INO; i++) 361 set_bit(i, info->si_imap); 362 363 s->s_op = &bfs_sops; 364 inode = bfs_iget(s, BFS_ROOT_INO); 365 if (IS_ERR(inode)) { 366 ret = PTR_ERR(inode); 367 goto out2; 368 } 369 s->s_root = d_alloc_root(inode); 370 if (!s->s_root) { 371 iput(inode); 372 ret = -ENOMEM; 373 goto out2; 374 } 375 376 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS; 377 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 378 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS; 379 info->si_freei = 0; 380 info->si_lf_eblk = 0; 381 382 /* can we read the last block? */ 383 bh = sb_bread(s, info->si_blocks - 1); 384 if (!bh) { 385 printf("Last block not available: %lu\n", info->si_blocks - 1); 386 ret = -EIO; 387 goto out3; 388 } 389 brelse(bh); 390 391 bh = NULL; 392 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) { 393 struct bfs_inode *di; 394 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 395 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 396 unsigned long eblock; 397 398 if (!off) { 399 brelse(bh); 400 bh = sb_bread(s, block); 401 } 402 403 if (!bh) 404 continue; 405 406 di = (struct bfs_inode *)bh->b_data + off; 407 408 /* test if filesystem is not corrupted */ 409 410 i_eoff = le32_to_cpu(di->i_eoffset); 411 i_sblock = le32_to_cpu(di->i_sblock); 412 i_eblock = le32_to_cpu(di->i_eblock); 413 s_size = le32_to_cpu(bfs_sb->s_end); 414 415 if (i_sblock > info->si_blocks || 416 i_eblock > info->si_blocks || 417 i_sblock > i_eblock || 418 i_eoff > s_size || 419 i_sblock * BFS_BSIZE > i_eoff) { 420 421 printf("Inode 0x%08x corrupted\n", i); 422 423 brelse(bh); 424 ret = -EIO; 425 goto out3; 426 } 427 428 if (!di->i_ino) { 429 info->si_freei++; 430 continue; 431 } 432 set_bit(i, info->si_imap); 433 info->si_freeb -= BFS_FILEBLOCKS(di); 434 435 eblock = le32_to_cpu(di->i_eblock); 436 if (eblock > info->si_lf_eblk) 437 info->si_lf_eblk = eblock; 438 } 439 brelse(bh); 440 brelse(sbh); 441 dump_imap("read_super", s); 442 return 0; 443 444 out3: 445 dput(s->s_root); 446 s->s_root = NULL; 447 out2: 448 kfree(info->si_imap); 449 out1: 450 brelse(sbh); 451 out: 452 mutex_destroy(&info->bfs_lock); 453 kfree(info); 454 s->s_fs_info = NULL; 455 return ret; 456 } 457 458 static int bfs_get_sb(struct file_system_type *fs_type, 459 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 460 { 461 return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt); 462 } 463 464 static struct file_system_type bfs_fs_type = { 465 .owner = THIS_MODULE, 466 .name = "bfs", 467 .get_sb = bfs_get_sb, 468 .kill_sb = kill_block_super, 469 .fs_flags = FS_REQUIRES_DEV, 470 }; 471 472 static int __init init_bfs_fs(void) 473 { 474 int err = init_inodecache(); 475 if (err) 476 goto out1; 477 err = register_filesystem(&bfs_fs_type); 478 if (err) 479 goto out; 480 return 0; 481 out: 482 destroy_inodecache(); 483 out1: 484 return err; 485 } 486 487 static void __exit exit_bfs_fs(void) 488 { 489 unregister_filesystem(&bfs_fs_type); 490 destroy_inodecache(); 491 } 492 493 module_init(init_bfs_fs) 494 module_exit(exit_bfs_fs) 495