1 /* 2 * fs/bfs/inode.c 3 * BFS superblock and inode operations. 4 * Copyright (C) 1999-2018 Tigran Aivazian <aivazian.tigran@gmail.com> 5 * From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds. 6 * Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 2005. 7 */ 8 9 #include <linux/module.h> 10 #include <linux/mm.h> 11 #include <linux/slab.h> 12 #include <linux/init.h> 13 #include <linux/fs.h> 14 #include <linux/buffer_head.h> 15 #include <linux/vfs.h> 16 #include <linux/writeback.h> 17 #include <linux/uio.h> 18 #include <linux/uaccess.h> 19 #include "bfs.h" 20 21 MODULE_AUTHOR("Tigran Aivazian <aivazian.tigran@gmail.com>"); 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 struct inode *bfs_iget(struct super_block *sb, unsigned long ino) 34 { 35 struct bfs_inode *di; 36 struct inode *inode; 37 struct buffer_head *bh; 38 int block, off; 39 40 inode = iget_locked(sb, ino); 41 if (!inode) 42 return ERR_PTR(-ENOMEM); 43 if (!(inode->i_state & I_NEW)) 44 return inode; 45 46 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) { 47 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino); 48 goto error; 49 } 50 51 block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 52 bh = sb_bread(inode->i_sb, block); 53 if (!bh) { 54 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, 55 ino); 56 goto error; 57 } 58 59 off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 60 di = (struct bfs_inode *)bh->b_data + off; 61 62 inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode); 63 if (le32_to_cpu(di->i_vtype) == BFS_VDIR) { 64 inode->i_mode |= S_IFDIR; 65 inode->i_op = &bfs_dir_inops; 66 inode->i_fop = &bfs_dir_operations; 67 } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) { 68 inode->i_mode |= S_IFREG; 69 inode->i_op = &bfs_file_inops; 70 inode->i_fop = &bfs_file_operations; 71 inode->i_mapping->a_ops = &bfs_aops; 72 } 73 74 BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock); 75 BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock); 76 BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); 77 i_uid_write(inode, le32_to_cpu(di->i_uid)); 78 i_gid_write(inode, le32_to_cpu(di->i_gid)); 79 set_nlink(inode, le32_to_cpu(di->i_nlink)); 80 inode->i_size = BFS_FILESIZE(di); 81 inode->i_blocks = BFS_FILEBLOCKS(di); 82 inode->i_atime.tv_sec = le32_to_cpu(di->i_atime); 83 inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime); 84 inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime); 85 inode->i_atime.tv_nsec = 0; 86 inode->i_mtime.tv_nsec = 0; 87 inode->i_ctime.tv_nsec = 0; 88 89 brelse(bh); 90 unlock_new_inode(inode); 91 return inode; 92 93 error: 94 iget_failed(inode); 95 return ERR_PTR(-EIO); 96 } 97 98 static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p) 99 { 100 if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) { 101 printf("Bad inode number %s:%08x\n", sb->s_id, ino); 102 return ERR_PTR(-EIO); 103 } 104 105 ino -= BFS_ROOT_INO; 106 107 *p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK); 108 if (!*p) { 109 printf("Unable to read inode %s:%08x\n", sb->s_id, ino); 110 return ERR_PTR(-EIO); 111 } 112 113 return (struct bfs_inode *)(*p)->b_data + ino % BFS_INODES_PER_BLOCK; 114 } 115 116 static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc) 117 { 118 struct bfs_sb_info *info = BFS_SB(inode->i_sb); 119 unsigned int ino = (u16)inode->i_ino; 120 unsigned long i_sblock; 121 struct bfs_inode *di; 122 struct buffer_head *bh; 123 int err = 0; 124 125 dprintf("ino=%08x\n", ino); 126 127 di = find_inode(inode->i_sb, ino, &bh); 128 if (IS_ERR(di)) 129 return PTR_ERR(di); 130 131 mutex_lock(&info->bfs_lock); 132 133 if (ino == BFS_ROOT_INO) 134 di->i_vtype = cpu_to_le32(BFS_VDIR); 135 else 136 di->i_vtype = cpu_to_le32(BFS_VREG); 137 138 di->i_ino = cpu_to_le16(ino); 139 di->i_mode = cpu_to_le32(inode->i_mode); 140 di->i_uid = cpu_to_le32(i_uid_read(inode)); 141 di->i_gid = cpu_to_le32(i_gid_read(inode)); 142 di->i_nlink = cpu_to_le32(inode->i_nlink); 143 di->i_atime = cpu_to_le32(inode->i_atime.tv_sec); 144 di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 145 di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 146 i_sblock = BFS_I(inode)->i_sblock; 147 di->i_sblock = cpu_to_le32(i_sblock); 148 di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock); 149 di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1); 150 151 mark_buffer_dirty(bh); 152 if (wbc->sync_mode == WB_SYNC_ALL) { 153 sync_dirty_buffer(bh); 154 if (buffer_req(bh) && !buffer_uptodate(bh)) 155 err = -EIO; 156 } 157 brelse(bh); 158 mutex_unlock(&info->bfs_lock); 159 return err; 160 } 161 162 static void bfs_evict_inode(struct inode *inode) 163 { 164 unsigned long ino = inode->i_ino; 165 struct bfs_inode *di; 166 struct buffer_head *bh; 167 struct super_block *s = inode->i_sb; 168 struct bfs_sb_info *info = BFS_SB(s); 169 struct bfs_inode_info *bi = BFS_I(inode); 170 171 dprintf("ino=%08lx\n", ino); 172 173 truncate_inode_pages_final(&inode->i_data); 174 invalidate_inode_buffers(inode); 175 clear_inode(inode); 176 177 if (inode->i_nlink) 178 return; 179 180 di = find_inode(s, inode->i_ino, &bh); 181 if (IS_ERR(di)) 182 return; 183 184 mutex_lock(&info->bfs_lock); 185 /* clear on-disk inode */ 186 memset(di, 0, sizeof(struct bfs_inode)); 187 mark_buffer_dirty(bh); 188 brelse(bh); 189 190 if (bi->i_dsk_ino) { 191 if (bi->i_sblock) 192 info->si_freeb += bi->i_eblock + 1 - bi->i_sblock; 193 info->si_freei++; 194 clear_bit(ino, info->si_imap); 195 bfs_dump_imap("evict_inode", s); 196 } 197 198 /* 199 * If this was the last file, make the previous block 200 * "last block of the last file" even if there is no 201 * real file there, saves us 1 gap. 202 */ 203 if (info->si_lf_eblk == bi->i_eblock) 204 info->si_lf_eblk = bi->i_sblock - 1; 205 mutex_unlock(&info->bfs_lock); 206 } 207 208 static void bfs_put_super(struct super_block *s) 209 { 210 struct bfs_sb_info *info = BFS_SB(s); 211 212 if (!info) 213 return; 214 215 mutex_destroy(&info->bfs_lock); 216 kfree(info); 217 s->s_fs_info = NULL; 218 } 219 220 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf) 221 { 222 struct super_block *s = dentry->d_sb; 223 struct bfs_sb_info *info = BFS_SB(s); 224 u64 id = huge_encode_dev(s->s_bdev->bd_dev); 225 buf->f_type = BFS_MAGIC; 226 buf->f_bsize = s->s_blocksize; 227 buf->f_blocks = info->si_blocks; 228 buf->f_bfree = buf->f_bavail = info->si_freeb; 229 buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO; 230 buf->f_ffree = info->si_freei; 231 buf->f_fsid.val[0] = (u32)id; 232 buf->f_fsid.val[1] = (u32)(id >> 32); 233 buf->f_namelen = BFS_NAMELEN; 234 return 0; 235 } 236 237 static struct kmem_cache *bfs_inode_cachep; 238 239 static struct inode *bfs_alloc_inode(struct super_block *sb) 240 { 241 struct bfs_inode_info *bi; 242 bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL); 243 if (!bi) 244 return NULL; 245 return &bi->vfs_inode; 246 } 247 248 static void bfs_free_inode(struct inode *inode) 249 { 250 kmem_cache_free(bfs_inode_cachep, BFS_I(inode)); 251 } 252 253 static void init_once(void *foo) 254 { 255 struct bfs_inode_info *bi = foo; 256 257 inode_init_once(&bi->vfs_inode); 258 } 259 260 static int __init init_inodecache(void) 261 { 262 bfs_inode_cachep = kmem_cache_create("bfs_inode_cache", 263 sizeof(struct bfs_inode_info), 264 0, (SLAB_RECLAIM_ACCOUNT| 265 SLAB_MEM_SPREAD|SLAB_ACCOUNT), 266 init_once); 267 if (bfs_inode_cachep == NULL) 268 return -ENOMEM; 269 return 0; 270 } 271 272 static void destroy_inodecache(void) 273 { 274 /* 275 * Make sure all delayed rcu free inodes are flushed before we 276 * destroy cache. 277 */ 278 rcu_barrier(); 279 kmem_cache_destroy(bfs_inode_cachep); 280 } 281 282 static const struct super_operations bfs_sops = { 283 .alloc_inode = bfs_alloc_inode, 284 .free_inode = bfs_free_inode, 285 .write_inode = bfs_write_inode, 286 .evict_inode = bfs_evict_inode, 287 .put_super = bfs_put_super, 288 .statfs = bfs_statfs, 289 }; 290 291 void bfs_dump_imap(const char *prefix, struct super_block *s) 292 { 293 #ifdef DEBUG 294 int i; 295 char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL); 296 297 if (!tmpbuf) 298 return; 299 for (i = BFS_SB(s)->si_lasti; i >= 0; i--) { 300 if (i > PAGE_SIZE - 100) break; 301 if (test_bit(i, BFS_SB(s)->si_imap)) 302 strcat(tmpbuf, "1"); 303 else 304 strcat(tmpbuf, "0"); 305 } 306 printf("%s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf); 307 free_page((unsigned long)tmpbuf); 308 #endif 309 } 310 311 static int bfs_fill_super(struct super_block *s, void *data, int silent) 312 { 313 struct buffer_head *bh, *sbh; 314 struct bfs_super_block *bfs_sb; 315 struct inode *inode; 316 unsigned i; 317 struct bfs_sb_info *info; 318 int ret = -EINVAL; 319 unsigned long i_sblock, i_eblock, i_eoff, s_size; 320 321 info = kzalloc(sizeof(*info), GFP_KERNEL); 322 if (!info) 323 return -ENOMEM; 324 mutex_init(&info->bfs_lock); 325 s->s_fs_info = info; 326 327 sb_set_blocksize(s, BFS_BSIZE); 328 329 sbh = sb_bread(s, 0); 330 if (!sbh) 331 goto out; 332 bfs_sb = (struct bfs_super_block *)sbh->b_data; 333 if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) { 334 if (!silent) 335 printf("No BFS filesystem on %s (magic=%08x)\n", s->s_id, le32_to_cpu(bfs_sb->s_magic)); 336 goto out1; 337 } 338 if (BFS_UNCLEAN(bfs_sb, s) && !silent) 339 printf("%s is unclean, continuing\n", s->s_id); 340 341 s->s_magic = BFS_MAGIC; 342 343 if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) || 344 le32_to_cpu(bfs_sb->s_start) < sizeof(struct bfs_super_block) + sizeof(struct bfs_dirent)) { 345 printf("Superblock is corrupted on %s\n", s->s_id); 346 goto out1; 347 } 348 349 info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / sizeof(struct bfs_inode) + BFS_ROOT_INO - 1; 350 if (info->si_lasti == BFS_MAX_LASTI) 351 printf("WARNING: filesystem %s was created with 512 inodes, the real maximum is 511, mounting anyway\n", s->s_id); 352 else if (info->si_lasti > BFS_MAX_LASTI) { 353 printf("Impossible last inode number %lu > %d on %s\n", info->si_lasti, BFS_MAX_LASTI, s->s_id); 354 goto out1; 355 } 356 for (i = 0; i < BFS_ROOT_INO; i++) 357 set_bit(i, info->si_imap); 358 359 s->s_op = &bfs_sops; 360 inode = bfs_iget(s, BFS_ROOT_INO); 361 if (IS_ERR(inode)) { 362 ret = PTR_ERR(inode); 363 goto out1; 364 } 365 s->s_root = d_make_root(inode); 366 if (!s->s_root) { 367 ret = -ENOMEM; 368 goto out1; 369 } 370 371 info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS; 372 info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS; 373 info->si_freei = 0; 374 info->si_lf_eblk = 0; 375 376 /* can we read the last block? */ 377 bh = sb_bread(s, info->si_blocks - 1); 378 if (!bh) { 379 printf("Last block not available on %s: %lu\n", s->s_id, info->si_blocks - 1); 380 ret = -EIO; 381 goto out2; 382 } 383 brelse(bh); 384 385 bh = NULL; 386 for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) { 387 struct bfs_inode *di; 388 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; 389 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; 390 unsigned long eblock; 391 392 if (!off) { 393 brelse(bh); 394 bh = sb_bread(s, block); 395 } 396 397 if (!bh) 398 continue; 399 400 di = (struct bfs_inode *)bh->b_data + off; 401 402 /* test if filesystem is not corrupted */ 403 404 i_eoff = le32_to_cpu(di->i_eoffset); 405 i_sblock = le32_to_cpu(di->i_sblock); 406 i_eblock = le32_to_cpu(di->i_eblock); 407 s_size = le32_to_cpu(bfs_sb->s_end); 408 409 if (i_sblock > info->si_blocks || 410 i_eblock > info->si_blocks || 411 i_sblock > i_eblock || 412 (i_eoff != le32_to_cpu(-1) && i_eoff > s_size) || 413 i_sblock * BFS_BSIZE > i_eoff) { 414 415 printf("Inode 0x%08x corrupted on %s\n", i, s->s_id); 416 417 brelse(bh); 418 ret = -EIO; 419 goto out2; 420 } 421 422 if (!di->i_ino) { 423 info->si_freei++; 424 continue; 425 } 426 set_bit(i, info->si_imap); 427 info->si_freeb -= BFS_FILEBLOCKS(di); 428 429 eblock = le32_to_cpu(di->i_eblock); 430 if (eblock > info->si_lf_eblk) 431 info->si_lf_eblk = eblock; 432 } 433 brelse(bh); 434 brelse(sbh); 435 bfs_dump_imap("fill_super", s); 436 return 0; 437 438 out2: 439 dput(s->s_root); 440 s->s_root = NULL; 441 out1: 442 brelse(sbh); 443 out: 444 mutex_destroy(&info->bfs_lock); 445 kfree(info); 446 s->s_fs_info = NULL; 447 return ret; 448 } 449 450 static struct dentry *bfs_mount(struct file_system_type *fs_type, 451 int flags, const char *dev_name, void *data) 452 { 453 return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super); 454 } 455 456 static struct file_system_type bfs_fs_type = { 457 .owner = THIS_MODULE, 458 .name = "bfs", 459 .mount = bfs_mount, 460 .kill_sb = kill_block_super, 461 .fs_flags = FS_REQUIRES_DEV, 462 }; 463 MODULE_ALIAS_FS("bfs"); 464 465 static int __init init_bfs_fs(void) 466 { 467 int err = init_inodecache(); 468 if (err) 469 goto out1; 470 err = register_filesystem(&bfs_fs_type); 471 if (err) 472 goto out; 473 return 0; 474 out: 475 destroy_inodecache(); 476 out1: 477 return err; 478 } 479 480 static void __exit exit_bfs_fs(void) 481 { 482 unregister_filesystem(&bfs_fs_type); 483 destroy_inodecache(); 484 } 485 486 module_init(init_bfs_fs) 487 module_exit(exit_bfs_fs) 488