1 /* 2 * QNX4 file system, Linux implementation. 3 * 4 * Version : 0.2.1 5 * 6 * Using parts of the xiafs filesystem. 7 * 8 * History : 9 * 10 * 01-06-1998 by Richard Frowijn : first release. 11 * 20-06-1998 by Frank Denis : Linux 2.1.99+ support, boot signature, misc. 12 * 30-06-1998 by Frank Denis : first step to write inodes. 13 */ 14 15 #include <linux/config.h> 16 #include <linux/module.h> 17 #include <linux/types.h> 18 #include <linux/string.h> 19 #include <linux/errno.h> 20 #include <linux/slab.h> 21 #include <linux/fs.h> 22 #include <linux/qnx4_fs.h> 23 #include <linux/init.h> 24 #include <linux/highuid.h> 25 #include <linux/smp_lock.h> 26 #include <linux/pagemap.h> 27 #include <linux/buffer_head.h> 28 #include <linux/vfs.h> 29 #include <asm/uaccess.h> 30 31 #define QNX4_VERSION 4 32 #define QNX4_BMNAME ".bitmap" 33 34 static struct super_operations qnx4_sops; 35 36 #ifdef CONFIG_QNX4FS_RW 37 38 int qnx4_sync_inode(struct inode *inode) 39 { 40 int err = 0; 41 # if 0 42 struct buffer_head *bh; 43 44 bh = qnx4_update_inode(inode); 45 if (bh && buffer_dirty(bh)) 46 { 47 sync_dirty_buffer(bh); 48 if (buffer_req(bh) && !buffer_uptodate(bh)) 49 { 50 printk ("IO error syncing qnx4 inode [%s:%08lx]\n", 51 inode->i_sb->s_id, inode->i_ino); 52 err = -1; 53 } 54 brelse (bh); 55 } else if (!bh) { 56 err = -1; 57 } 58 # endif 59 60 return err; 61 } 62 63 static void qnx4_delete_inode(struct inode *inode) 64 { 65 QNX4DEBUG(("qnx4: deleting inode [%lu]\n", (unsigned long) inode->i_ino)); 66 truncate_inode_pages(&inode->i_data, 0); 67 inode->i_size = 0; 68 qnx4_truncate(inode); 69 lock_kernel(); 70 qnx4_free_inode(inode); 71 unlock_kernel(); 72 } 73 74 static void qnx4_write_super(struct super_block *sb) 75 { 76 lock_kernel(); 77 QNX4DEBUG(("qnx4: write_super\n")); 78 sb->s_dirt = 0; 79 unlock_kernel(); 80 } 81 82 static int qnx4_write_inode(struct inode *inode, int unused) 83 { 84 struct qnx4_inode_entry *raw_inode; 85 int block, ino; 86 struct buffer_head *bh; 87 ino = inode->i_ino; 88 89 QNX4DEBUG(("qnx4: write inode 1.\n")); 90 if (inode->i_nlink == 0) { 91 return 0; 92 } 93 if (!ino) { 94 printk("qnx4: bad inode number on dev %s: %d is out of range\n", 95 inode->i_sb->s_id, ino); 96 return -EIO; 97 } 98 QNX4DEBUG(("qnx4: write inode 2.\n")); 99 block = ino / QNX4_INODES_PER_BLOCK; 100 lock_kernel(); 101 if (!(bh = sb_bread(inode->i_sb, block))) { 102 printk("qnx4: major problem: unable to read inode from dev " 103 "%s\n", inode->i_sb->s_id); 104 unlock_kernel(); 105 return -EIO; 106 } 107 raw_inode = ((struct qnx4_inode_entry *) bh->b_data) + 108 (ino % QNX4_INODES_PER_BLOCK); 109 raw_inode->di_mode = cpu_to_le16(inode->i_mode); 110 raw_inode->di_uid = cpu_to_le16(fs_high2lowuid(inode->i_uid)); 111 raw_inode->di_gid = cpu_to_le16(fs_high2lowgid(inode->i_gid)); 112 raw_inode->di_nlink = cpu_to_le16(inode->i_nlink); 113 raw_inode->di_size = cpu_to_le32(inode->i_size); 114 raw_inode->di_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 115 raw_inode->di_atime = cpu_to_le32(inode->i_atime.tv_sec); 116 raw_inode->di_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 117 raw_inode->di_first_xtnt.xtnt_size = cpu_to_le32(inode->i_blocks); 118 mark_buffer_dirty(bh); 119 brelse(bh); 120 unlock_kernel(); 121 return 0; 122 } 123 124 #endif 125 126 static void qnx4_put_super(struct super_block *sb); 127 static struct inode *qnx4_alloc_inode(struct super_block *sb); 128 static void qnx4_destroy_inode(struct inode *inode); 129 static void qnx4_read_inode(struct inode *); 130 static int qnx4_remount(struct super_block *sb, int *flags, char *data); 131 static int qnx4_statfs(struct super_block *, struct kstatfs *); 132 133 static struct super_operations qnx4_sops = 134 { 135 .alloc_inode = qnx4_alloc_inode, 136 .destroy_inode = qnx4_destroy_inode, 137 .read_inode = qnx4_read_inode, 138 .put_super = qnx4_put_super, 139 .statfs = qnx4_statfs, 140 .remount_fs = qnx4_remount, 141 #ifdef CONFIG_QNX4FS_RW 142 .write_inode = qnx4_write_inode, 143 .delete_inode = qnx4_delete_inode, 144 .write_super = qnx4_write_super, 145 #endif 146 }; 147 148 static int qnx4_remount(struct super_block *sb, int *flags, char *data) 149 { 150 struct qnx4_sb_info *qs; 151 152 qs = qnx4_sb(sb); 153 qs->Version = QNX4_VERSION; 154 #ifndef CONFIG_QNX4FS_RW 155 *flags |= MS_RDONLY; 156 #endif 157 if (*flags & MS_RDONLY) { 158 return 0; 159 } 160 161 mark_buffer_dirty(qs->sb_buf); 162 163 return 0; 164 } 165 166 static struct buffer_head *qnx4_getblk(struct inode *inode, int nr, 167 int create) 168 { 169 struct buffer_head *result = NULL; 170 171 if ( nr >= 0 ) 172 nr = qnx4_block_map( inode, nr ); 173 if (nr) { 174 result = sb_getblk(inode->i_sb, nr); 175 return result; 176 } 177 if (!create) { 178 return NULL; 179 } 180 #if 0 181 tmp = qnx4_new_block(inode->i_sb); 182 if (!tmp) { 183 return NULL; 184 } 185 result = sb_getblk(inode->i_sb, tmp); 186 if (tst) { 187 qnx4_free_block(inode->i_sb, tmp); 188 brelse(result); 189 goto repeat; 190 } 191 tst = tmp; 192 #endif 193 inode->i_ctime = CURRENT_TIME_SEC; 194 mark_inode_dirty(inode); 195 return result; 196 } 197 198 struct buffer_head *qnx4_bread(struct inode *inode, int block, int create) 199 { 200 struct buffer_head *bh; 201 202 bh = qnx4_getblk(inode, block, create); 203 if (!bh || buffer_uptodate(bh)) { 204 return bh; 205 } 206 ll_rw_block(READ, 1, &bh); 207 wait_on_buffer(bh); 208 if (buffer_uptodate(bh)) { 209 return bh; 210 } 211 brelse(bh); 212 213 return NULL; 214 } 215 216 static int qnx4_get_block( struct inode *inode, sector_t iblock, struct buffer_head *bh, int create ) 217 { 218 unsigned long phys; 219 220 QNX4DEBUG(("qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock)); 221 222 phys = qnx4_block_map( inode, iblock ); 223 if ( phys ) { 224 // logical block is before EOF 225 map_bh(bh, inode->i_sb, phys); 226 } else if ( create ) { 227 // to be done. 228 } 229 return 0; 230 } 231 232 unsigned long qnx4_block_map( struct inode *inode, long iblock ) 233 { 234 int ix; 235 long offset, i_xblk; 236 unsigned long block = 0; 237 struct buffer_head *bh = NULL; 238 struct qnx4_xblk *xblk = NULL; 239 struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode); 240 u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts); 241 242 if ( iblock < le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size) ) { 243 // iblock is in the first extent. This is easy. 244 block = le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_blk) + iblock - 1; 245 } else { 246 // iblock is beyond first extent. We have to follow the extent chain. 247 i_xblk = le32_to_cpu(qnx4_inode->di_xblk); 248 offset = iblock - le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size); 249 ix = 0; 250 while ( --nxtnt > 0 ) { 251 if ( ix == 0 ) { 252 // read next xtnt block. 253 bh = sb_bread(inode->i_sb, i_xblk - 1); 254 if ( !bh ) { 255 QNX4DEBUG(("qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1)); 256 return -EIO; 257 } 258 xblk = (struct qnx4_xblk*)bh->b_data; 259 if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) { 260 QNX4DEBUG(("qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk)); 261 return -EIO; 262 } 263 } 264 if ( offset < le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size) ) { 265 // got it! 266 block = le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_blk) + offset - 1; 267 break; 268 } 269 offset -= le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size); 270 if ( ++ix >= xblk->xblk_num_xtnts ) { 271 i_xblk = le32_to_cpu(xblk->xblk_next_xblk); 272 ix = 0; 273 brelse( bh ); 274 bh = NULL; 275 } 276 } 277 if ( bh ) 278 brelse( bh ); 279 } 280 281 QNX4DEBUG(("qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block)); 282 return block; 283 } 284 285 static int qnx4_statfs(struct super_block *sb, struct kstatfs *buf) 286 { 287 lock_kernel(); 288 289 buf->f_type = sb->s_magic; 290 buf->f_bsize = sb->s_blocksize; 291 buf->f_blocks = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8; 292 buf->f_bfree = qnx4_count_free_blocks(sb); 293 buf->f_bavail = buf->f_bfree; 294 buf->f_namelen = QNX4_NAME_MAX; 295 296 unlock_kernel(); 297 298 return 0; 299 } 300 301 /* 302 * Check the root directory of the filesystem to make sure 303 * it really _is_ a qnx4 filesystem, and to check the size 304 * of the directory entry. 305 */ 306 static const char *qnx4_checkroot(struct super_block *sb) 307 { 308 struct buffer_head *bh; 309 struct qnx4_inode_entry *rootdir; 310 int rd, rl; 311 int i, j; 312 int found = 0; 313 314 if (*(qnx4_sb(sb)->sb->RootDir.di_fname) != '/') { 315 return "no qnx4 filesystem (no root dir)."; 316 } else { 317 QNX4DEBUG(("QNX4 filesystem found on dev %s.\n", sb->s_id)); 318 rd = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_blk) - 1; 319 rl = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_size); 320 for (j = 0; j < rl; j++) { 321 bh = sb_bread(sb, rd + j); /* root dir, first block */ 322 if (bh == NULL) { 323 return "unable to read root entry."; 324 } 325 for (i = 0; i < QNX4_INODES_PER_BLOCK; i++) { 326 rootdir = (struct qnx4_inode_entry *) (bh->b_data + i * QNX4_DIR_ENTRY_SIZE); 327 if (rootdir->di_fname != NULL) { 328 QNX4DEBUG(("Rootdir entry found : [%s]\n", rootdir->di_fname)); 329 if (!strncmp(rootdir->di_fname, QNX4_BMNAME, sizeof QNX4_BMNAME)) { 330 found = 1; 331 qnx4_sb(sb)->BitMap = kmalloc( sizeof( struct qnx4_inode_entry ), GFP_KERNEL ); 332 if (!qnx4_sb(sb)->BitMap) { 333 brelse (bh); 334 return "not enough memory for bitmap inode"; 335 } 336 memcpy( qnx4_sb(sb)->BitMap, rootdir, sizeof( struct qnx4_inode_entry ) ); /* keep bitmap inode known */ 337 break; 338 } 339 } 340 } 341 brelse(bh); 342 if (found != 0) { 343 break; 344 } 345 } 346 if (found == 0) { 347 return "bitmap file not found."; 348 } 349 } 350 return NULL; 351 } 352 353 static int qnx4_fill_super(struct super_block *s, void *data, int silent) 354 { 355 struct buffer_head *bh; 356 struct inode *root; 357 const char *errmsg; 358 struct qnx4_sb_info *qs; 359 360 qs = kmalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL); 361 if (!qs) 362 return -ENOMEM; 363 s->s_fs_info = qs; 364 memset(qs, 0, sizeof(struct qnx4_sb_info)); 365 366 sb_set_blocksize(s, QNX4_BLOCK_SIZE); 367 368 /* Check the superblock signature. Since the qnx4 code is 369 dangerous, we should leave as quickly as possible 370 if we don't belong here... */ 371 bh = sb_bread(s, 1); 372 if (!bh) { 373 printk("qnx4: unable to read the superblock\n"); 374 goto outnobh; 375 } 376 if ( le32_to_cpup((__le32*) bh->b_data) != QNX4_SUPER_MAGIC ) { 377 if (!silent) 378 printk("qnx4: wrong fsid in superblock.\n"); 379 goto out; 380 } 381 s->s_op = &qnx4_sops; 382 s->s_magic = QNX4_SUPER_MAGIC; 383 #ifndef CONFIG_QNX4FS_RW 384 s->s_flags |= MS_RDONLY; /* Yup, read-only yet */ 385 #endif 386 qnx4_sb(s)->sb_buf = bh; 387 qnx4_sb(s)->sb = (struct qnx4_super_block *) bh->b_data; 388 389 390 /* check before allocating dentries, inodes, .. */ 391 errmsg = qnx4_checkroot(s); 392 if (errmsg != NULL) { 393 if (!silent) 394 printk("qnx4: %s\n", errmsg); 395 goto out; 396 } 397 398 /* does root not have inode number QNX4_ROOT_INO ?? */ 399 root = iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK); 400 if (!root) { 401 printk("qnx4: get inode failed\n"); 402 goto out; 403 } 404 405 s->s_root = d_alloc_root(root); 406 if (s->s_root == NULL) 407 goto outi; 408 409 brelse(bh); 410 411 return 0; 412 413 outi: 414 iput(root); 415 out: 416 brelse(bh); 417 outnobh: 418 kfree(qs); 419 s->s_fs_info = NULL; 420 return -EINVAL; 421 } 422 423 static void qnx4_put_super(struct super_block *sb) 424 { 425 struct qnx4_sb_info *qs = qnx4_sb(sb); 426 kfree( qs->BitMap ); 427 kfree( qs ); 428 sb->s_fs_info = NULL; 429 return; 430 } 431 432 static int qnx4_writepage(struct page *page, struct writeback_control *wbc) 433 { 434 return block_write_full_page(page,qnx4_get_block, wbc); 435 } 436 static int qnx4_readpage(struct file *file, struct page *page) 437 { 438 return block_read_full_page(page,qnx4_get_block); 439 } 440 static int qnx4_prepare_write(struct file *file, struct page *page, 441 unsigned from, unsigned to) 442 { 443 struct qnx4_inode_info *qnx4_inode = qnx4_i(page->mapping->host); 444 return cont_prepare_write(page, from, to, qnx4_get_block, 445 &qnx4_inode->mmu_private); 446 } 447 static sector_t qnx4_bmap(struct address_space *mapping, sector_t block) 448 { 449 return generic_block_bmap(mapping,block,qnx4_get_block); 450 } 451 static struct address_space_operations qnx4_aops = { 452 .readpage = qnx4_readpage, 453 .writepage = qnx4_writepage, 454 .sync_page = block_sync_page, 455 .prepare_write = qnx4_prepare_write, 456 .commit_write = generic_commit_write, 457 .bmap = qnx4_bmap 458 }; 459 460 static void qnx4_read_inode(struct inode *inode) 461 { 462 struct buffer_head *bh; 463 struct qnx4_inode_entry *raw_inode; 464 int block, ino; 465 struct super_block *sb = inode->i_sb; 466 struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode); 467 468 ino = inode->i_ino; 469 inode->i_mode = 0; 470 471 QNX4DEBUG(("Reading inode : [%d]\n", ino)); 472 if (!ino) { 473 printk("qnx4: bad inode number on dev %s: %d is out of range\n", 474 sb->s_id, ino); 475 return; 476 } 477 block = ino / QNX4_INODES_PER_BLOCK; 478 479 if (!(bh = sb_bread(sb, block))) { 480 printk("qnx4: major problem: unable to read inode from dev " 481 "%s\n", sb->s_id); 482 return; 483 } 484 raw_inode = ((struct qnx4_inode_entry *) bh->b_data) + 485 (ino % QNX4_INODES_PER_BLOCK); 486 487 inode->i_mode = le16_to_cpu(raw_inode->di_mode); 488 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->di_uid); 489 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->di_gid); 490 inode->i_nlink = le16_to_cpu(raw_inode->di_nlink); 491 inode->i_size = le32_to_cpu(raw_inode->di_size); 492 inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->di_mtime); 493 inode->i_mtime.tv_nsec = 0; 494 inode->i_atime.tv_sec = le32_to_cpu(raw_inode->di_atime); 495 inode->i_atime.tv_nsec = 0; 496 inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->di_ctime); 497 inode->i_ctime.tv_nsec = 0; 498 inode->i_blocks = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size); 499 inode->i_blksize = QNX4_DIR_ENTRY_SIZE; 500 501 memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE); 502 if (S_ISREG(inode->i_mode)) { 503 inode->i_op = &qnx4_file_inode_operations; 504 inode->i_fop = &qnx4_file_operations; 505 inode->i_mapping->a_ops = &qnx4_aops; 506 qnx4_i(inode)->mmu_private = inode->i_size; 507 } else if (S_ISDIR(inode->i_mode)) { 508 inode->i_op = &qnx4_dir_inode_operations; 509 inode->i_fop = &qnx4_dir_operations; 510 } else if (S_ISLNK(inode->i_mode)) { 511 inode->i_op = &page_symlink_inode_operations; 512 inode->i_mapping->a_ops = &qnx4_aops; 513 qnx4_i(inode)->mmu_private = inode->i_size; 514 } else 515 printk("qnx4: bad inode %d on dev %s\n",ino,sb->s_id); 516 brelse(bh); 517 } 518 519 static kmem_cache_t *qnx4_inode_cachep; 520 521 static struct inode *qnx4_alloc_inode(struct super_block *sb) 522 { 523 struct qnx4_inode_info *ei; 524 ei = kmem_cache_alloc(qnx4_inode_cachep, SLAB_KERNEL); 525 if (!ei) 526 return NULL; 527 return &ei->vfs_inode; 528 } 529 530 static void qnx4_destroy_inode(struct inode *inode) 531 { 532 kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode)); 533 } 534 535 static void init_once(void *foo, kmem_cache_t * cachep, 536 unsigned long flags) 537 { 538 struct qnx4_inode_info *ei = (struct qnx4_inode_info *) foo; 539 540 if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) == 541 SLAB_CTOR_CONSTRUCTOR) 542 inode_init_once(&ei->vfs_inode); 543 } 544 545 static int init_inodecache(void) 546 { 547 qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache", 548 sizeof(struct qnx4_inode_info), 549 0, SLAB_RECLAIM_ACCOUNT, 550 init_once, NULL); 551 if (qnx4_inode_cachep == NULL) 552 return -ENOMEM; 553 return 0; 554 } 555 556 static void destroy_inodecache(void) 557 { 558 if (kmem_cache_destroy(qnx4_inode_cachep)) 559 printk(KERN_INFO 560 "qnx4_inode_cache: not all structures were freed\n"); 561 } 562 563 static struct super_block *qnx4_get_sb(struct file_system_type *fs_type, 564 int flags, const char *dev_name, void *data) 565 { 566 return get_sb_bdev(fs_type, flags, dev_name, data, qnx4_fill_super); 567 } 568 569 static struct file_system_type qnx4_fs_type = { 570 .owner = THIS_MODULE, 571 .name = "qnx4", 572 .get_sb = qnx4_get_sb, 573 .kill_sb = kill_block_super, 574 .fs_flags = FS_REQUIRES_DEV, 575 }; 576 577 static int __init init_qnx4_fs(void) 578 { 579 int err; 580 581 err = init_inodecache(); 582 if (err) 583 return err; 584 585 err = register_filesystem(&qnx4_fs_type); 586 if (err) { 587 destroy_inodecache(); 588 return err; 589 } 590 591 printk("QNX4 filesystem 0.2.3 registered.\n"); 592 return 0; 593 } 594 595 static void __exit exit_qnx4_fs(void) 596 { 597 unregister_filesystem(&qnx4_fs_type); 598 destroy_inodecache(); 599 } 600 601 module_init(init_qnx4_fs) 602 module_exit(exit_qnx4_fs) 603 MODULE_LICENSE("GPL"); 604 605