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 static void bfs_write_super(struct super_block *s); 35 void dump_imap(const char *prefix, struct super_block *s); 36 37 struct inode *bfs_iget(struct super_block *sb, unsigned long ino) 38 { 39 struct bfs_inode *di; 40 struct inode *inode; 41 struct buffer_head *bh; 42 int block, off; 43 44 inode = iget_locked(sb, ino); 45 if (IS_ERR(inode)) 46 return ERR_PTR(-ENOMEM); 47 if (!(inode->i_state & I_NEW)) 48 return inode; 49 50 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) { 51 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino); 52 goto error; 53 } 54 55 block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 56 bh = sb_bread(inode->i_sb, block); 57 if (!bh) { 58 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, 59 ino); 60 goto error; 61 } 62 63 off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 64 di = (struct bfs_inode *)bh->b_data + off; 65 66 inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode); 67 if (le32_to_cpu(di->i_vtype) == BFS_VDIR) { 68 inode->i_mode |= S_IFDIR; 69 inode->i_op = &bfs_dir_inops; 70 inode->i_fop = &bfs_dir_operations; 71 } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) { 72 inode->i_mode |= S_IFREG; 73 inode->i_op = &bfs_file_inops; 74 inode->i_fop = &bfs_file_operations; 75 inode->i_mapping->a_ops = &bfs_aops; 76 } 77 78 BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock); 79 BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock); 80 BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); 81 inode->i_uid = le32_to_cpu(di->i_uid); 82 inode->i_gid = le32_to_cpu(di->i_gid); 83 inode->i_nlink = le32_to_cpu(di->i_nlink); 84 inode->i_size = BFS_FILESIZE(di); 85 inode->i_blocks = BFS_FILEBLOCKS(di); 86 inode->i_atime.tv_sec = le32_to_cpu(di->i_atime); 87 inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime); 88 inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime); 89 inode->i_atime.tv_nsec = 0; 90 inode->i_mtime.tv_nsec = 0; 91 inode->i_ctime.tv_nsec = 0; 92 93 brelse(bh); 94 unlock_new_inode(inode); 95 return inode; 96 97 error: 98 iget_failed(inode); 99 return ERR_PTR(-EIO); 100 } 101 102 static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p) 103 { 104 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) { 105 printf("Bad inode number %s:%08x\n", sb->s_id, ino); 106 return ERR_PTR(-EIO); 107 } 108 109 ino -= BFS_ROOT_INO; 110 111 *p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK); 112 if (!*p) { 113 printf("Unable to read inode %s:%08x\n", sb->s_id, ino); 114 return ERR_PTR(-EIO); 115 } 116 117 return (struct bfs_inode *)(*p)->b_data + ino % BFS_INODES_PER_BLOCK; 118 } 119 120 static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc) 121 { 122 struct bfs_sb_info *info = BFS_SB(inode->i_sb); 123 unsigned int ino = (u16)inode->i_ino; 124 unsigned long i_sblock; 125 struct bfs_inode *di; 126 struct buffer_head *bh; 127 int err = 0; 128 129 dprintf("ino=%08x\n", ino); 130 131 di = find_inode(inode->i_sb, ino, &bh); 132 if (IS_ERR(di)) 133 return PTR_ERR(di); 134 135 mutex_lock(&info->bfs_lock); 136 137 if (ino == BFS_ROOT_INO) 138 di->i_vtype = cpu_to_le32(BFS_VDIR); 139 else 140 di->i_vtype = cpu_to_le32(BFS_VREG); 141 142 di->i_ino = cpu_to_le16(ino); 143 di->i_mode = cpu_to_le32(inode->i_mode); 144 di->i_uid = cpu_to_le32(inode->i_uid); 145 di->i_gid = cpu_to_le32(inode->i_gid); 146 di->i_nlink = cpu_to_le32(inode->i_nlink); 147 di->i_atime = cpu_to_le32(inode->i_atime.tv_sec); 148 di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 149 di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 150 i_sblock = BFS_I(inode)->i_sblock; 151 di->i_sblock = cpu_to_le32(i_sblock); 152 di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock); 153 di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1); 154 155 mark_buffer_dirty(bh); 156 if (wbc->sync_mode == WB_SYNC_ALL) { 157 sync_dirty_buffer(bh); 158 if (buffer_req(bh) && !buffer_uptodate(bh)) 159 err = -EIO; 160 } 161 brelse(bh); 162 mutex_unlock(&info->bfs_lock); 163 return err; 164 } 165 166 static void bfs_evict_inode(struct inode *inode) 167 { 168 unsigned long ino = inode->i_ino; 169 struct bfs_inode *di; 170 struct buffer_head *bh; 171 struct super_block *s = inode->i_sb; 172 struct bfs_sb_info *info = BFS_SB(s); 173 struct bfs_inode_info *bi = BFS_I(inode); 174 175 dprintf("ino=%08lx\n", ino); 176 177 truncate_inode_pages(&inode->i_data, 0); 178 invalidate_inode_buffers(inode); 179 end_writeback(inode); 180 181 if (inode->i_nlink) 182 return; 183 184 di = find_inode(s, inode->i_ino, &bh); 185 if (IS_ERR(di)) 186 return; 187 188 mutex_lock(&info->bfs_lock); 189 /* clear on-disk inode */ 190 memset(di, 0, sizeof(struct bfs_inode)); 191 mark_buffer_dirty(bh); 192 brelse(bh); 193 194 if (bi->i_dsk_ino) { 195 if (bi->i_sblock) 196 info->si_freeb += bi->i_eblock + 1 - bi->i_sblock; 197 info->si_freei++; 198 clear_bit(ino, info->si_imap); 199 dump_imap("delete_inode", s); 200 } 201 202 /* 203 * If this was the last file, make the previous block 204 * "last block of the last file" even if there is no 205 * real file there, saves us 1 gap. 206 */ 207 if (info->si_lf_eblk == bi->i_eblock) { 208 info->si_lf_eblk = bi->i_sblock - 1; 209 mark_buffer_dirty(info->si_sbh); 210 } 211 mutex_unlock(&info->bfs_lock); 212 } 213 214 static int bfs_sync_fs(struct super_block *sb, int wait) 215 { 216 struct bfs_sb_info *info = BFS_SB(sb); 217 218 mutex_lock(&info->bfs_lock); 219 mark_buffer_dirty(info->si_sbh); 220 sb->s_dirt = 0; 221 mutex_unlock(&info->bfs_lock); 222 223 return 0; 224 } 225 226 static void bfs_write_super(struct super_block *sb) 227 { 228 if (!(sb->s_flags & MS_RDONLY)) 229 bfs_sync_fs(sb, 1); 230 else 231 sb->s_dirt = 0; 232 } 233 234 static void bfs_put_super(struct super_block *s) 235 { 236 struct bfs_sb_info *info = BFS_SB(s); 237 238 if (!info) 239 return; 240 241 lock_kernel(); 242 243 if (s->s_dirt) 244 bfs_write_super(s); 245 246 brelse(info->si_sbh); 247 mutex_destroy(&info->bfs_lock); 248 kfree(info->si_imap); 249 kfree(info); 250 s->s_fs_info = NULL; 251 252 unlock_kernel(); 253 } 254 255 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf) 256 { 257 struct super_block *s = dentry->d_sb; 258 struct bfs_sb_info *info = BFS_SB(s); 259 u64 id = huge_encode_dev(s->s_bdev->bd_dev); 260 buf->f_type = BFS_MAGIC; 261 buf->f_bsize = s->s_blocksize; 262 buf->f_blocks = info->si_blocks; 263 buf->f_bfree = buf->f_bavail = info->si_freeb; 264 buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO; 265 buf->f_ffree = info->si_freei; 266 buf->f_fsid.val[0] = (u32)id; 267 buf->f_fsid.val[1] = (u32)(id >> 32); 268 buf->f_namelen = BFS_NAMELEN; 269 return 0; 270 } 271 272 static struct kmem_cache *bfs_inode_cachep; 273 274 static struct inode *bfs_alloc_inode(struct super_block *sb) 275 { 276 struct bfs_inode_info *bi; 277 bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL); 278 if (!bi) 279 return NULL; 280 return &bi->vfs_inode; 281 } 282 283 static void bfs_destroy_inode(struct inode *inode) 284 { 285 kmem_cache_free(bfs_inode_cachep, BFS_I(inode)); 286 } 287 288 static void init_once(void *foo) 289 { 290 struct bfs_inode_info *bi = foo; 291 292 inode_init_once(&bi->vfs_inode); 293 } 294 295 static int init_inodecache(void) 296 { 297 bfs_inode_cachep = kmem_cache_create("bfs_inode_cache", 298 sizeof(struct bfs_inode_info), 299 0, (SLAB_RECLAIM_ACCOUNT| 300 SLAB_MEM_SPREAD), 301 init_once); 302 if (bfs_inode_cachep == NULL) 303 return -ENOMEM; 304 return 0; 305 } 306 307 static void destroy_inodecache(void) 308 { 309 kmem_cache_destroy(bfs_inode_cachep); 310 } 311 312 static const struct super_operations bfs_sops = { 313 .alloc_inode = bfs_alloc_inode, 314 .destroy_inode = bfs_destroy_inode, 315 .write_inode = bfs_write_inode, 316 .evict_inode = bfs_evict_inode, 317 .put_super = bfs_put_super, 318 .write_super = bfs_write_super, 319 .sync_fs = bfs_sync_fs, 320 .statfs = bfs_statfs, 321 }; 322 323 void dump_imap(const char *prefix, struct super_block *s) 324 { 325 #ifdef DEBUG 326 int i; 327 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL); 328 329 if (!tmpbuf) 330 return; 331 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) { 332 if (i > PAGE_SIZE - 100) break; 333 if (test_bit(i, BFS_SB(s)->si_imap)) 334 strcat(tmpbuf, "1"); 335 else 336 strcat(tmpbuf, "0"); 337 } 338 printf("BFS-fs: %s: lasti=%08lx <%s>\n", 339 prefix, BFS_SB(s)->si_lasti, tmpbuf); 340 free_page((unsigned long)tmpbuf); 341 #endif 342 } 343 344 static int bfs_fill_super(struct super_block *s, void *data, int silent) 345 { 346 struct buffer_head *bh; 347 struct bfs_super_block *bfs_sb; 348 struct inode *inode; 349 unsigned i, imap_len; 350 struct bfs_sb_info *info; 351 int ret = -EINVAL; 352 unsigned long i_sblock, i_eblock, i_eoff, s_size; 353 354 info = kzalloc(sizeof(*info), GFP_KERNEL); 355 if (!info) 356 return -ENOMEM; 357 mutex_init(&info->bfs_lock); 358 s->s_fs_info = info; 359 360 sb_set_blocksize(s, BFS_BSIZE); 361 362 info->si_sbh = sb_bread(s, 0); 363 if (!info->si_sbh) 364 goto out; 365 bfs_sb = (struct bfs_super_block *)info->si_sbh->b_data; 366 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) { 367 if (!silent) 368 printf("No BFS filesystem on %s (magic=%08x)\n", 369 s->s_id, le32_to_cpu(bfs_sb->s_magic)); 370 goto out1; 371 } 372 if (BFS_UNCLEAN(bfs_sb, s) && !silent) 373 printf("%s is unclean, continuing\n", s->s_id); 374 375 s->s_magic = BFS_MAGIC; 376 377 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) { 378 printf("Superblock is corrupted\n"); 379 goto out1; 380 } 381 382 info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / 383 sizeof(struct bfs_inode) 384 + BFS_ROOT_INO - 1; 385 imap_len = (info->si_lasti / 8) + 1; 386 info->si_imap = kzalloc(imap_len, GFP_KERNEL); 387 if (!info->si_imap) 388 goto out1; 389 for (i = 0; i < BFS_ROOT_INO; i++) 390 set_bit(i, info->si_imap); 391 392 s->s_op = &bfs_sops; 393 inode = bfs_iget(s, BFS_ROOT_INO); 394 if (IS_ERR(inode)) { 395 ret = PTR_ERR(inode); 396 goto out2; 397 } 398 s->s_root = d_alloc_root(inode); 399 if (!s->s_root) { 400 iput(inode); 401 ret = -ENOMEM; 402 goto out2; 403 } 404 405 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS; 406 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 407 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS; 408 info->si_freei = 0; 409 info->si_lf_eblk = 0; 410 411 /* can we read the last block? */ 412 bh = sb_bread(s, info->si_blocks - 1); 413 if (!bh) { 414 printf("Last block not available: %lu\n", info->si_blocks - 1); 415 ret = -EIO; 416 goto out3; 417 } 418 brelse(bh); 419 420 bh = NULL; 421 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) { 422 struct bfs_inode *di; 423 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 424 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 425 unsigned long eblock; 426 427 if (!off) { 428 brelse(bh); 429 bh = sb_bread(s, block); 430 } 431 432 if (!bh) 433 continue; 434 435 di = (struct bfs_inode *)bh->b_data + off; 436 437 /* test if filesystem is not corrupted */ 438 439 i_eoff = le32_to_cpu(di->i_eoffset); 440 i_sblock = le32_to_cpu(di->i_sblock); 441 i_eblock = le32_to_cpu(di->i_eblock); 442 s_size = le32_to_cpu(bfs_sb->s_end); 443 444 if (i_sblock > info->si_blocks || 445 i_eblock > info->si_blocks || 446 i_sblock > i_eblock || 447 i_eoff > s_size || 448 i_sblock * BFS_BSIZE > i_eoff) { 449 450 printf("Inode 0x%08x corrupted\n", i); 451 452 brelse(bh); 453 ret = -EIO; 454 goto out3; 455 } 456 457 if (!di->i_ino) { 458 info->si_freei++; 459 continue; 460 } 461 set_bit(i, info->si_imap); 462 info->si_freeb -= BFS_FILEBLOCKS(di); 463 464 eblock = le32_to_cpu(di->i_eblock); 465 if (eblock > info->si_lf_eblk) 466 info->si_lf_eblk = eblock; 467 } 468 brelse(bh); 469 if (!(s->s_flags & MS_RDONLY)) { 470 mark_buffer_dirty(info->si_sbh); 471 s->s_dirt = 1; 472 } 473 dump_imap("read_super", s); 474 return 0; 475 476 out3: 477 dput(s->s_root); 478 s->s_root = NULL; 479 out2: 480 kfree(info->si_imap); 481 out1: 482 brelse(info->si_sbh); 483 out: 484 mutex_destroy(&info->bfs_lock); 485 kfree(info); 486 s->s_fs_info = NULL; 487 return ret; 488 } 489 490 static int bfs_get_sb(struct file_system_type *fs_type, 491 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 492 { 493 return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt); 494 } 495 496 static struct file_system_type bfs_fs_type = { 497 .owner = THIS_MODULE, 498 .name = "bfs", 499 .get_sb = bfs_get_sb, 500 .kill_sb = kill_block_super, 501 .fs_flags = FS_REQUIRES_DEV, 502 }; 503 504 static int __init init_bfs_fs(void) 505 { 506 int err = init_inodecache(); 507 if (err) 508 goto out1; 509 err = register_filesystem(&bfs_fs_type); 510 if (err) 511 goto out; 512 return 0; 513 out: 514 destroy_inodecache(); 515 out1: 516 return err; 517 } 518 519 static void __exit exit_bfs_fs(void) 520 { 521 unregister_filesystem(&bfs_fs_type); 522 destroy_inodecache(); 523 } 524 525 module_init(init_bfs_fs) 526 module_exit(exit_bfs_fs) 527