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/buffer_head.h> 16 #include <linux/vfs.h> 17 #include <linux/writeback.h> 18 #include <asm/uaccess.h> 19 #include "bfs.h" 20 21 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>"); 22 MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux"); 23 MODULE_LICENSE("GPL"); 24 25 #undef DEBUG 26 27 #ifdef DEBUG 28 #define dprintf(x...) printf(x) 29 #else 30 #define dprintf(x...) 31 #endif 32 33 void dump_imap(const char *prefix, struct super_block *s); 34 35 struct inode *bfs_iget(struct super_block *sb, unsigned long ino) 36 { 37 struct bfs_inode *di; 38 struct inode *inode; 39 struct buffer_head *bh; 40 int block, off; 41 42 inode = iget_locked(sb, ino); 43 if (!inode) 44 return ERR_PTR(-ENOMEM); 45 if (!(inode->i_state & I_NEW)) 46 return inode; 47 48 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) { 49 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino); 50 goto error; 51 } 52 53 block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 54 bh = sb_bread(inode->i_sb, block); 55 if (!bh) { 56 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, 57 ino); 58 goto error; 59 } 60 61 off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 62 di = (struct bfs_inode *)bh->b_data + off; 63 64 inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode); 65 if (le32_to_cpu(di->i_vtype) == BFS_VDIR) { 66 inode->i_mode |= S_IFDIR; 67 inode->i_op = &bfs_dir_inops; 68 inode->i_fop = &bfs_dir_operations; 69 } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) { 70 inode->i_mode |= S_IFREG; 71 inode->i_op = &bfs_file_inops; 72 inode->i_fop = &bfs_file_operations; 73 inode->i_mapping->a_ops = &bfs_aops; 74 } 75 76 BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock); 77 BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock); 78 BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); 79 i_uid_write(inode, le32_to_cpu(di->i_uid)); 80 i_gid_write(inode, le32_to_cpu(di->i_gid)); 81 set_nlink(inode, le32_to_cpu(di->i_nlink)); 82 inode->i_size = BFS_FILESIZE(di); 83 inode->i_blocks = BFS_FILEBLOCKS(di); 84 inode->i_atime.tv_sec = le32_to_cpu(di->i_atime); 85 inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime); 86 inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime); 87 inode->i_atime.tv_nsec = 0; 88 inode->i_mtime.tv_nsec = 0; 89 inode->i_ctime.tv_nsec = 0; 90 91 brelse(bh); 92 unlock_new_inode(inode); 93 return inode; 94 95 error: 96 iget_failed(inode); 97 return ERR_PTR(-EIO); 98 } 99 100 static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p) 101 { 102 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) { 103 printf("Bad inode number %s:%08x\n", sb->s_id, ino); 104 return ERR_PTR(-EIO); 105 } 106 107 ino -= BFS_ROOT_INO; 108 109 *p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK); 110 if (!*p) { 111 printf("Unable to read inode %s:%08x\n", sb->s_id, ino); 112 return ERR_PTR(-EIO); 113 } 114 115 return (struct bfs_inode *)(*p)->b_data + ino % BFS_INODES_PER_BLOCK; 116 } 117 118 static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc) 119 { 120 struct bfs_sb_info *info = BFS_SB(inode->i_sb); 121 unsigned int ino = (u16)inode->i_ino; 122 unsigned long i_sblock; 123 struct bfs_inode *di; 124 struct buffer_head *bh; 125 int err = 0; 126 127 dprintf("ino=%08x\n", ino); 128 129 di = find_inode(inode->i_sb, ino, &bh); 130 if (IS_ERR(di)) 131 return PTR_ERR(di); 132 133 mutex_lock(&info->bfs_lock); 134 135 if (ino == BFS_ROOT_INO) 136 di->i_vtype = cpu_to_le32(BFS_VDIR); 137 else 138 di->i_vtype = cpu_to_le32(BFS_VREG); 139 140 di->i_ino = cpu_to_le16(ino); 141 di->i_mode = cpu_to_le32(inode->i_mode); 142 di->i_uid = cpu_to_le32(i_uid_read(inode)); 143 di->i_gid = cpu_to_le32(i_gid_read(inode)); 144 di->i_nlink = cpu_to_le32(inode->i_nlink); 145 di->i_atime = cpu_to_le32(inode->i_atime.tv_sec); 146 di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 147 di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 148 i_sblock = BFS_I(inode)->i_sblock; 149 di->i_sblock = cpu_to_le32(i_sblock); 150 di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock); 151 di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1); 152 153 mark_buffer_dirty(bh); 154 if (wbc->sync_mode == WB_SYNC_ALL) { 155 sync_dirty_buffer(bh); 156 if (buffer_req(bh) && !buffer_uptodate(bh)) 157 err = -EIO; 158 } 159 brelse(bh); 160 mutex_unlock(&info->bfs_lock); 161 return err; 162 } 163 164 static void bfs_evict_inode(struct inode *inode) 165 { 166 unsigned long ino = inode->i_ino; 167 struct bfs_inode *di; 168 struct buffer_head *bh; 169 struct super_block *s = inode->i_sb; 170 struct bfs_sb_info *info = BFS_SB(s); 171 struct bfs_inode_info *bi = BFS_I(inode); 172 173 dprintf("ino=%08lx\n", ino); 174 175 truncate_inode_pages(&inode->i_data, 0); 176 invalidate_inode_buffers(inode); 177 clear_inode(inode); 178 179 if (inode->i_nlink) 180 return; 181 182 di = find_inode(s, inode->i_ino, &bh); 183 if (IS_ERR(di)) 184 return; 185 186 mutex_lock(&info->bfs_lock); 187 /* clear on-disk inode */ 188 memset(di, 0, sizeof(struct bfs_inode)); 189 mark_buffer_dirty(bh); 190 brelse(bh); 191 192 if (bi->i_dsk_ino) { 193 if (bi->i_sblock) 194 info->si_freeb += bi->i_eblock + 1 - bi->i_sblock; 195 info->si_freei++; 196 clear_bit(ino, info->si_imap); 197 dump_imap("delete_inode", s); 198 } 199 200 /* 201 * If this was the last file, make the previous block 202 * "last block of the last file" even if there is no 203 * real file there, saves us 1 gap. 204 */ 205 if (info->si_lf_eblk == bi->i_eblock) 206 info->si_lf_eblk = bi->i_sblock - 1; 207 mutex_unlock(&info->bfs_lock); 208 } 209 210 static void bfs_put_super(struct super_block *s) 211 { 212 struct bfs_sb_info *info = BFS_SB(s); 213 214 if (!info) 215 return; 216 217 mutex_destroy(&info->bfs_lock); 218 kfree(info->si_imap); 219 kfree(info); 220 s->s_fs_info = NULL; 221 } 222 223 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf) 224 { 225 struct super_block *s = dentry->d_sb; 226 struct bfs_sb_info *info = BFS_SB(s); 227 u64 id = huge_encode_dev(s->s_bdev->bd_dev); 228 buf->f_type = BFS_MAGIC; 229 buf->f_bsize = s->s_blocksize; 230 buf->f_blocks = info->si_blocks; 231 buf->f_bfree = buf->f_bavail = info->si_freeb; 232 buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO; 233 buf->f_ffree = info->si_freei; 234 buf->f_fsid.val[0] = (u32)id; 235 buf->f_fsid.val[1] = (u32)(id >> 32); 236 buf->f_namelen = BFS_NAMELEN; 237 return 0; 238 } 239 240 static struct kmem_cache *bfs_inode_cachep; 241 242 static struct inode *bfs_alloc_inode(struct super_block *sb) 243 { 244 struct bfs_inode_info *bi; 245 bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL); 246 if (!bi) 247 return NULL; 248 return &bi->vfs_inode; 249 } 250 251 static void bfs_i_callback(struct rcu_head *head) 252 { 253 struct inode *inode = container_of(head, struct inode, i_rcu); 254 kmem_cache_free(bfs_inode_cachep, BFS_I(inode)); 255 } 256 257 static void bfs_destroy_inode(struct inode *inode) 258 { 259 call_rcu(&inode->i_rcu, bfs_i_callback); 260 } 261 262 static void init_once(void *foo) 263 { 264 struct bfs_inode_info *bi = foo; 265 266 inode_init_once(&bi->vfs_inode); 267 } 268 269 static int init_inodecache(void) 270 { 271 bfs_inode_cachep = kmem_cache_create("bfs_inode_cache", 272 sizeof(struct bfs_inode_info), 273 0, (SLAB_RECLAIM_ACCOUNT| 274 SLAB_MEM_SPREAD), 275 init_once); 276 if (bfs_inode_cachep == NULL) 277 return -ENOMEM; 278 return 0; 279 } 280 281 static void destroy_inodecache(void) 282 { 283 /* 284 * Make sure all delayed rcu free inodes are flushed before we 285 * destroy cache. 286 */ 287 rcu_barrier(); 288 kmem_cache_destroy(bfs_inode_cachep); 289 } 290 291 static const struct super_operations bfs_sops = { 292 .alloc_inode = bfs_alloc_inode, 293 .destroy_inode = bfs_destroy_inode, 294 .write_inode = bfs_write_inode, 295 .evict_inode = bfs_evict_inode, 296 .put_super = bfs_put_super, 297 .statfs = bfs_statfs, 298 }; 299 300 void dump_imap(const char *prefix, struct super_block *s) 301 { 302 #ifdef DEBUG 303 int i; 304 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL); 305 306 if (!tmpbuf) 307 return; 308 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) { 309 if (i > PAGE_SIZE - 100) break; 310 if (test_bit(i, BFS_SB(s)->si_imap)) 311 strcat(tmpbuf, "1"); 312 else 313 strcat(tmpbuf, "0"); 314 } 315 printf("BFS-fs: %s: lasti=%08lx <%s>\n", 316 prefix, BFS_SB(s)->si_lasti, tmpbuf); 317 free_page((unsigned long)tmpbuf); 318 #endif 319 } 320 321 static int bfs_fill_super(struct super_block *s, void *data, int silent) 322 { 323 struct buffer_head *bh, *sbh; 324 struct bfs_super_block *bfs_sb; 325 struct inode *inode; 326 unsigned i, imap_len; 327 struct bfs_sb_info *info; 328 int ret = -EINVAL; 329 unsigned long i_sblock, i_eblock, i_eoff, s_size; 330 331 info = kzalloc(sizeof(*info), GFP_KERNEL); 332 if (!info) 333 return -ENOMEM; 334 mutex_init(&info->bfs_lock); 335 s->s_fs_info = info; 336 337 sb_set_blocksize(s, BFS_BSIZE); 338 339 sbh = sb_bread(s, 0); 340 if (!sbh) 341 goto out; 342 bfs_sb = (struct bfs_super_block *)sbh->b_data; 343 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) { 344 if (!silent) 345 printf("No BFS filesystem on %s (magic=%08x)\n", 346 s->s_id, le32_to_cpu(bfs_sb->s_magic)); 347 goto out1; 348 } 349 if (BFS_UNCLEAN(bfs_sb, s) && !silent) 350 printf("%s is unclean, continuing\n", s->s_id); 351 352 s->s_magic = BFS_MAGIC; 353 354 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) { 355 printf("Superblock is corrupted\n"); 356 goto out1; 357 } 358 359 info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / 360 sizeof(struct bfs_inode) 361 + BFS_ROOT_INO - 1; 362 imap_len = (info->si_lasti / 8) + 1; 363 info->si_imap = kzalloc(imap_len, GFP_KERNEL); 364 if (!info->si_imap) 365 goto out1; 366 for (i = 0; i < BFS_ROOT_INO; i++) 367 set_bit(i, info->si_imap); 368 369 s->s_op = &bfs_sops; 370 inode = bfs_iget(s, BFS_ROOT_INO); 371 if (IS_ERR(inode)) { 372 ret = PTR_ERR(inode); 373 goto out2; 374 } 375 s->s_root = d_make_root(inode); 376 if (!s->s_root) { 377 ret = -ENOMEM; 378 goto out2; 379 } 380 381 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS; 382 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 383 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS; 384 info->si_freei = 0; 385 info->si_lf_eblk = 0; 386 387 /* can we read the last block? */ 388 bh = sb_bread(s, info->si_blocks - 1); 389 if (!bh) { 390 printf("Last block not available: %lu\n", info->si_blocks - 1); 391 ret = -EIO; 392 goto out3; 393 } 394 brelse(bh); 395 396 bh = NULL; 397 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) { 398 struct bfs_inode *di; 399 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 400 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 401 unsigned long eblock; 402 403 if (!off) { 404 brelse(bh); 405 bh = sb_bread(s, block); 406 } 407 408 if (!bh) 409 continue; 410 411 di = (struct bfs_inode *)bh->b_data + off; 412 413 /* test if filesystem is not corrupted */ 414 415 i_eoff = le32_to_cpu(di->i_eoffset); 416 i_sblock = le32_to_cpu(di->i_sblock); 417 i_eblock = le32_to_cpu(di->i_eblock); 418 s_size = le32_to_cpu(bfs_sb->s_end); 419 420 if (i_sblock > info->si_blocks || 421 i_eblock > info->si_blocks || 422 i_sblock > i_eblock || 423 i_eoff > s_size || 424 i_sblock * BFS_BSIZE > i_eoff) { 425 426 printf("Inode 0x%08x corrupted\n", i); 427 428 brelse(bh); 429 ret = -EIO; 430 goto out3; 431 } 432 433 if (!di->i_ino) { 434 info->si_freei++; 435 continue; 436 } 437 set_bit(i, info->si_imap); 438 info->si_freeb -= BFS_FILEBLOCKS(di); 439 440 eblock = le32_to_cpu(di->i_eblock); 441 if (eblock > info->si_lf_eblk) 442 info->si_lf_eblk = eblock; 443 } 444 brelse(bh); 445 brelse(sbh); 446 dump_imap("read_super", s); 447 return 0; 448 449 out3: 450 dput(s->s_root); 451 s->s_root = NULL; 452 out2: 453 kfree(info->si_imap); 454 out1: 455 brelse(sbh); 456 out: 457 mutex_destroy(&info->bfs_lock); 458 kfree(info); 459 s->s_fs_info = NULL; 460 return ret; 461 } 462 463 static struct dentry *bfs_mount(struct file_system_type *fs_type, 464 int flags, const char *dev_name, void *data) 465 { 466 return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super); 467 } 468 469 static struct file_system_type bfs_fs_type = { 470 .owner = THIS_MODULE, 471 .name = "bfs", 472 .mount = bfs_mount, 473 .kill_sb = kill_block_super, 474 .fs_flags = FS_REQUIRES_DEV, 475 }; 476 MODULE_ALIAS_FS("bfs"); 477 478 static int __init init_bfs_fs(void) 479 { 480 int err = init_inodecache(); 481 if (err) 482 goto out1; 483 err = register_filesystem(&bfs_fs_type); 484 if (err) 485 goto out; 486 return 0; 487 out: 488 destroy_inodecache(); 489 out1: 490 return err; 491 } 492 493 static void __exit exit_bfs_fs(void) 494 { 495 unregister_filesystem(&bfs_fs_type); 496 destroy_inodecache(); 497 } 498 499 module_init(init_bfs_fs) 500 module_exit(exit_bfs_fs) 501