| 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 (IS_ERR(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) |