1 /* 2 * fs/bfs/inode.c 3 * BFS superblock and inode operations. 4 * Copyright (C) 1999-2006 Tigran Aivazian <aivazian.tigran@gmail.com> 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 <linux/uio.h> 19 #include <linux/uaccess.h> 20 #include "bfs.h" 21 22 MODULE_AUTHOR("Tigran Aivazian <aivazian.tigran@gmail.com>"); 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 struct inode *bfs_iget(struct super_block *sb, unsigned long ino) 35 { 36 struct bfs_inode *di; 37 struct inode *inode; 38 struct buffer_head *bh; 39 int block, off; 40 41 inode = iget_locked(sb, ino); 42 if (!inode) 43 return ERR_PTR(-ENOMEM); 44 if (!(inode->i_state & I_NEW)) 45 return inode; 46 47 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) { 48 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino); 49 goto error; 50 } 51 52 block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 53 bh = sb_bread(inode->i_sb, block); 54 if (!bh) { 55 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, 56 ino); 57 goto error; 58 } 59 60 off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 61 di = (struct bfs_inode *)bh->b_data + off; 62 63 inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode); 64 if (le32_to_cpu(di->i_vtype) == BFS_VDIR) { 65 inode->i_mode |= S_IFDIR; 66 inode->i_op = &bfs_dir_inops; 67 inode->i_fop = &bfs_dir_operations; 68 } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) { 69 inode->i_mode |= S_IFREG; 70 inode->i_op = &bfs_file_inops; 71 inode->i_fop = &bfs_file_operations; 72 inode->i_mapping->a_ops = &bfs_aops; 73 } 74 75 BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock); 76 BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock); 77 BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); 78 i_uid_write(inode, le32_to_cpu(di->i_uid)); 79 i_gid_write(inode, le32_to_cpu(di->i_gid)); 80 set_nlink(inode, le32_to_cpu(di->i_nlink)); 81 inode->i_size = BFS_FILESIZE(di); 82 inode->i_blocks = BFS_FILEBLOCKS(di); 83 inode->i_atime.tv_sec = le32_to_cpu(di->i_atime); 84 inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime); 85 inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime); 86 inode->i_atime.tv_nsec = 0; 87 inode->i_mtime.tv_nsec = 0; 88 inode->i_ctime.tv_nsec = 0; 89 90 brelse(bh); 91 unlock_new_inode(inode); 92 return inode; 93 94 error: 95 iget_failed(inode); 96 return ERR_PTR(-EIO); 97 } 98 99 static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p) 100 { 101 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) { 102 printf("Bad inode number %s:%08x\n", sb->s_id, ino); 103 return ERR_PTR(-EIO); 104 } 105 106 ino -= BFS_ROOT_INO; 107 108 *p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK); 109 if (!*p) { 110 printf("Unable to read inode %s:%08x\n", sb->s_id, ino); 111 return ERR_PTR(-EIO); 112 } 113 114 return (struct bfs_inode *)(*p)->b_data + ino % BFS_INODES_PER_BLOCK; 115 } 116 117 static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc) 118 { 119 struct bfs_sb_info *info = BFS_SB(inode->i_sb); 120 unsigned int ino = (u16)inode->i_ino; 121 unsigned long i_sblock; 122 struct bfs_inode *di; 123 struct buffer_head *bh; 124 int err = 0; 125 126 dprintf("ino=%08x\n", ino); 127 128 di = find_inode(inode->i_sb, ino, &bh); 129 if (IS_ERR(di)) 130 return PTR_ERR(di); 131 132 mutex_lock(&info->bfs_lock); 133 134 if (ino == BFS_ROOT_INO) 135 di->i_vtype = cpu_to_le32(BFS_VDIR); 136 else 137 di->i_vtype = cpu_to_le32(BFS_VREG); 138 139 di->i_ino = cpu_to_le16(ino); 140 di->i_mode = cpu_to_le32(inode->i_mode); 141 di->i_uid = cpu_to_le32(i_uid_read(inode)); 142 di->i_gid = cpu_to_le32(i_gid_read(inode)); 143 di->i_nlink = cpu_to_le32(inode->i_nlink); 144 di->i_atime = cpu_to_le32(inode->i_atime.tv_sec); 145 di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 146 di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 147 i_sblock = BFS_I(inode)->i_sblock; 148 di->i_sblock = cpu_to_le32(i_sblock); 149 di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock); 150 di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1); 151 152 mark_buffer_dirty(bh); 153 if (wbc->sync_mode == WB_SYNC_ALL) { 154 sync_dirty_buffer(bh); 155 if (buffer_req(bh) && !buffer_uptodate(bh)) 156 err = -EIO; 157 } 158 brelse(bh); 159 mutex_unlock(&info->bfs_lock); 160 return err; 161 } 162 163 static void bfs_evict_inode(struct inode *inode) 164 { 165 unsigned long ino = inode->i_ino; 166 struct bfs_inode *di; 167 struct buffer_head *bh; 168 struct super_block *s = inode->i_sb; 169 struct bfs_sb_info *info = BFS_SB(s); 170 struct bfs_inode_info *bi = BFS_I(inode); 171 172 dprintf("ino=%08lx\n", ino); 173 174 truncate_inode_pages_final(&inode->i_data); 175 invalidate_inode_buffers(inode); 176 clear_inode(inode); 177 178 if (inode->i_nlink) 179 return; 180 181 di = find_inode(s, inode->i_ino, &bh); 182 if (IS_ERR(di)) 183 return; 184 185 mutex_lock(&info->bfs_lock); 186 /* clear on-disk inode */ 187 memset(di, 0, sizeof(struct bfs_inode)); 188 mark_buffer_dirty(bh); 189 brelse(bh); 190 191 if (bi->i_dsk_ino) { 192 if (bi->i_sblock) 193 info->si_freeb += bi->i_eblock + 1 - bi->i_sblock; 194 info->si_freei++; 195 clear_bit(ino, info->si_imap); 196 bfs_dump_imap("delete_inode", s); 197 } 198 199 /* 200 * If this was the last file, make the previous block 201 * "last block of the last file" even if there is no 202 * real file there, saves us 1 gap. 203 */ 204 if (info->si_lf_eblk == bi->i_eblock) 205 info->si_lf_eblk = bi->i_sblock - 1; 206 mutex_unlock(&info->bfs_lock); 207 } 208 209 static void bfs_put_super(struct super_block *s) 210 { 211 struct bfs_sb_info *info = BFS_SB(s); 212 213 if (!info) 214 return; 215 216 mutex_destroy(&info->bfs_lock); 217 kfree(info->si_imap); 218 kfree(info); 219 s->s_fs_info = NULL; 220 } 221 222 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf) 223 { 224 struct super_block *s = dentry->d_sb; 225 struct bfs_sb_info *info = BFS_SB(s); 226 u64 id = huge_encode_dev(s->s_bdev->bd_dev); 227 buf->f_type = BFS_MAGIC; 228 buf->f_bsize = s->s_blocksize; 229 buf->f_blocks = info->si_blocks; 230 buf->f_bfree = buf->f_bavail = info->si_freeb; 231 buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO; 232 buf->f_ffree = info->si_freei; 233 buf->f_fsid.val[0] = (u32)id; 234 buf->f_fsid.val[1] = (u32)(id >> 32); 235 buf->f_namelen = BFS_NAMELEN; 236 return 0; 237 } 238 239 static struct kmem_cache *bfs_inode_cachep; 240 241 static struct inode *bfs_alloc_inode(struct super_block *sb) 242 { 243 struct bfs_inode_info *bi; 244 bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL); 245 if (!bi) 246 return NULL; 247 return &bi->vfs_inode; 248 } 249 250 static void bfs_i_callback(struct rcu_head *head) 251 { 252 struct inode *inode = container_of(head, struct inode, i_rcu); 253 kmem_cache_free(bfs_inode_cachep, BFS_I(inode)); 254 } 255 256 static void bfs_destroy_inode(struct inode *inode) 257 { 258 call_rcu(&inode->i_rcu, bfs_i_callback); 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 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|SLAB_ACCOUNT), 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 /* 283 * Make sure all delayed rcu free inodes are flushed before we 284 * destroy cache. 285 */ 286 rcu_barrier(); 287 kmem_cache_destroy(bfs_inode_cachep); 288 } 289 290 static const struct super_operations bfs_sops = { 291 .alloc_inode = bfs_alloc_inode, 292 .destroy_inode = bfs_destroy_inode, 293 .write_inode = bfs_write_inode, 294 .evict_inode = bfs_evict_inode, 295 .put_super = bfs_put_super, 296 .statfs = bfs_statfs, 297 }; 298 299 void bfs_dump_imap(const char *prefix, struct super_block *s) 300 { 301 #ifdef DEBUG 302 int i; 303 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL); 304 305 if (!tmpbuf) 306 return; 307 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) { 308 if (i > PAGE_SIZE - 100) break; 309 if (test_bit(i, BFS_SB(s)->si_imap)) 310 strcat(tmpbuf, "1"); 311 else 312 strcat(tmpbuf, "0"); 313 } 314 printf("BFS-fs: %s: lasti=%08lx <%s>\n", 315 prefix, BFS_SB(s)->si_lasti, tmpbuf); 316 free_page((unsigned long)tmpbuf); 317 #endif 318 } 319 320 static int bfs_fill_super(struct super_block *s, void *data, int silent) 321 { 322 struct buffer_head *bh, *sbh; 323 struct bfs_super_block *bfs_sb; 324 struct inode *inode; 325 unsigned i, imap_len; 326 struct bfs_sb_info *info; 327 int ret = -EINVAL; 328 unsigned long i_sblock, i_eblock, i_eoff, s_size; 329 330 info = kzalloc(sizeof(*info), GFP_KERNEL); 331 if (!info) 332 return -ENOMEM; 333 mutex_init(&info->bfs_lock); 334 s->s_fs_info = info; 335 336 sb_set_blocksize(s, BFS_BSIZE); 337 338 sbh = sb_bread(s, 0); 339 if (!sbh) 340 goto out; 341 bfs_sb = (struct bfs_super_block *)sbh->b_data; 342 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) { 343 if (!silent) 344 printf("No BFS filesystem on %s (magic=%08x)\n", 345 s->s_id, le32_to_cpu(bfs_sb->s_magic)); 346 goto out1; 347 } 348 if (BFS_UNCLEAN(bfs_sb, s) && !silent) 349 printf("%s is unclean, continuing\n", s->s_id); 350 351 s->s_magic = BFS_MAGIC; 352 353 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) || 354 le32_to_cpu(bfs_sb->s_start) < BFS_BSIZE) { 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 | __GFP_NOWARN); 364 if (!info->si_imap) { 365 printf("Cannot allocate %u bytes\n", imap_len); 366 goto out1; 367 } 368 for (i = 0; i < BFS_ROOT_INO; i++) 369 set_bit(i, info->si_imap); 370 371 s->s_op = &bfs_sops; 372 inode = bfs_iget(s, BFS_ROOT_INO); 373 if (IS_ERR(inode)) { 374 ret = PTR_ERR(inode); 375 goto out2; 376 } 377 s->s_root = d_make_root(inode); 378 if (!s->s_root) { 379 ret = -ENOMEM; 380 goto out2; 381 } 382 383 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS; 384 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 385 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS; 386 info->si_freei = 0; 387 info->si_lf_eblk = 0; 388 389 /* can we read the last block? */ 390 bh = sb_bread(s, info->si_blocks - 1); 391 if (!bh) { 392 printf("Last block not available: %lu\n", info->si_blocks - 1); 393 ret = -EIO; 394 goto out3; 395 } 396 brelse(bh); 397 398 bh = NULL; 399 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) { 400 struct bfs_inode *di; 401 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 402 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 403 unsigned long eblock; 404 405 if (!off) { 406 brelse(bh); 407 bh = sb_bread(s, block); 408 } 409 410 if (!bh) 411 continue; 412 413 di = (struct bfs_inode *)bh->b_data + off; 414 415 /* test if filesystem is not corrupted */ 416 417 i_eoff = le32_to_cpu(di->i_eoffset); 418 i_sblock = le32_to_cpu(di->i_sblock); 419 i_eblock = le32_to_cpu(di->i_eblock); 420 s_size = le32_to_cpu(bfs_sb->s_end); 421 422 if (i_sblock > info->si_blocks || 423 i_eblock > info->si_blocks || 424 i_sblock > i_eblock || 425 (i_eoff != le32_to_cpu(-1) && i_eoff > s_size) || 426 i_sblock * BFS_BSIZE > i_eoff) { 427 428 printf("Inode 0x%08x corrupted\n", i); 429 430 brelse(bh); 431 ret = -EIO; 432 goto out3; 433 } 434 435 if (!di->i_ino) { 436 info->si_freei++; 437 continue; 438 } 439 set_bit(i, info->si_imap); 440 info->si_freeb -= BFS_FILEBLOCKS(di); 441 442 eblock = le32_to_cpu(di->i_eblock); 443 if (eblock > info->si_lf_eblk) 444 info->si_lf_eblk = eblock; 445 } 446 brelse(bh); 447 brelse(sbh); 448 bfs_dump_imap("read_super", s); 449 return 0; 450 451 out3: 452 dput(s->s_root); 453 s->s_root = NULL; 454 out2: 455 kfree(info->si_imap); 456 out1: 457 brelse(sbh); 458 out: 459 mutex_destroy(&info->bfs_lock); 460 kfree(info); 461 s->s_fs_info = NULL; 462 return ret; 463 } 464 465 static struct dentry *bfs_mount(struct file_system_type *fs_type, 466 int flags, const char *dev_name, void *data) 467 { 468 return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super); 469 } 470 471 static struct file_system_type bfs_fs_type = { 472 .owner = THIS_MODULE, 473 .name = "bfs", 474 .mount = bfs_mount, 475 .kill_sb = kill_block_super, 476 .fs_flags = FS_REQUIRES_DEV, 477 }; 478 MODULE_ALIAS_FS("bfs"); 479 480 static int __init init_bfs_fs(void) 481 { 482 int err = init_inodecache(); 483 if (err) 484 goto out1; 485 err = register_filesystem(&bfs_fs_type); 486 if (err) 487 goto out; 488 return 0; 489 out: 490 destroy_inodecache(); 491 out1: 492 return err; 493 } 494 495 static void __exit exit_bfs_fs(void) 496 { 497 unregister_filesystem(&bfs_fs_type); 498 destroy_inodecache(); 499 } 500 501 module_init(init_bfs_fs) 502 module_exit(exit_bfs_fs) 503