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 inode->i_size = 0; 67 qnx4_truncate(inode); 68 lock_kernel(); 69 qnx4_free_inode(inode); 70 unlock_kernel(); 71 } 72 73 static void qnx4_write_super(struct super_block *sb) 74 { 75 lock_kernel(); 76 QNX4DEBUG(("qnx4: write_super\n")); 77 sb->s_dirt = 0; 78 unlock_kernel(); 79 } 80 81 static int qnx4_write_inode(struct inode *inode, int unused) 82 { 83 struct qnx4_inode_entry *raw_inode; 84 int block, ino; 85 struct buffer_head *bh; 86 ino = inode->i_ino; 87 88 QNX4DEBUG(("qnx4: write inode 1.\n")); 89 if (inode->i_nlink == 0) { 90 return 0; 91 } 92 if (!ino) { 93 printk("qnx4: bad inode number on dev %s: %d is out of range\n", 94 inode->i_sb->s_id, ino); 95 return -EIO; 96 } 97 QNX4DEBUG(("qnx4: write inode 2.\n")); 98 block = ino / QNX4_INODES_PER_BLOCK; 99 lock_kernel(); 100 if (!(bh = sb_bread(inode->i_sb, block))) { 101 printk("qnx4: major problem: unable to read inode from dev " 102 "%s\n", inode->i_sb->s_id); 103 unlock_kernel(); 104 return -EIO; 105 } 106 raw_inode = ((struct qnx4_inode_entry *) bh->b_data) + 107 (ino % QNX4_INODES_PER_BLOCK); 108 raw_inode->di_mode = cpu_to_le16(inode->i_mode); 109 raw_inode->di_uid = cpu_to_le16(fs_high2lowuid(inode->i_uid)); 110 raw_inode->di_gid = cpu_to_le16(fs_high2lowgid(inode->i_gid)); 111 raw_inode->di_nlink = cpu_to_le16(inode->i_nlink); 112 raw_inode->di_size = cpu_to_le32(inode->i_size); 113 raw_inode->di_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 114 raw_inode->di_atime = cpu_to_le32(inode->i_atime.tv_sec); 115 raw_inode->di_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 116 raw_inode->di_first_xtnt.xtnt_size = cpu_to_le32(inode->i_blocks); 117 mark_buffer_dirty(bh); 118 brelse(bh); 119 unlock_kernel(); 120 return 0; 121 } 122 123 #endif 124 125 static void qnx4_put_super(struct super_block *sb); 126 static struct inode *qnx4_alloc_inode(struct super_block *sb); 127 static void qnx4_destroy_inode(struct inode *inode); 128 static void qnx4_read_inode(struct inode *); 129 static int qnx4_remount(struct super_block *sb, int *flags, char *data); 130 static int qnx4_statfs(struct super_block *, struct kstatfs *); 131 132 static struct super_operations qnx4_sops = 133 { 134 .alloc_inode = qnx4_alloc_inode, 135 .destroy_inode = qnx4_destroy_inode, 136 .read_inode = qnx4_read_inode, 137 .put_super = qnx4_put_super, 138 .statfs = qnx4_statfs, 139 .remount_fs = qnx4_remount, 140 #ifdef CONFIG_QNX4FS_RW 141 .write_inode = qnx4_write_inode, 142 .delete_inode = qnx4_delete_inode, 143 .write_super = qnx4_write_super, 144 #endif 145 }; 146 147 static int qnx4_remount(struct super_block *sb, int *flags, char *data) 148 { 149 struct qnx4_sb_info *qs; 150 151 qs = qnx4_sb(sb); 152 qs->Version = QNX4_VERSION; 153 #ifndef CONFIG_QNX4FS_RW 154 *flags |= MS_RDONLY; 155 #endif 156 if (*flags & MS_RDONLY) { 157 return 0; 158 } 159 160 mark_buffer_dirty(qs->sb_buf); 161 162 return 0; 163 } 164 165 static struct buffer_head *qnx4_getblk(struct inode *inode, int nr, 166 int create) 167 { 168 struct buffer_head *result = NULL; 169 170 if ( nr >= 0 ) 171 nr = qnx4_block_map( inode, nr ); 172 if (nr) { 173 result = sb_getblk(inode->i_sb, nr); 174 return result; 175 } 176 if (!create) { 177 return NULL; 178 } 179 #if 0 180 tmp = qnx4_new_block(inode->i_sb); 181 if (!tmp) { 182 return NULL; 183 } 184 result = sb_getblk(inode->i_sb, tmp); 185 if (tst) { 186 qnx4_free_block(inode->i_sb, tmp); 187 brelse(result); 188 goto repeat; 189 } 190 tst = tmp; 191 #endif 192 inode->i_ctime = CURRENT_TIME_SEC; 193 mark_inode_dirty(inode); 194 return result; 195 } 196 197 struct buffer_head *qnx4_bread(struct inode *inode, int block, int create) 198 { 199 struct buffer_head *bh; 200 201 bh = qnx4_getblk(inode, block, create); 202 if (!bh || buffer_uptodate(bh)) { 203 return bh; 204 } 205 ll_rw_block(READ, 1, &bh); 206 wait_on_buffer(bh); 207 if (buffer_uptodate(bh)) { 208 return bh; 209 } 210 brelse(bh); 211 212 return NULL; 213 } 214 215 static int qnx4_get_block( struct inode *inode, sector_t iblock, struct buffer_head *bh, int create ) 216 { 217 unsigned long phys; 218 219 QNX4DEBUG(("qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock)); 220 221 phys = qnx4_block_map( inode, iblock ); 222 if ( phys ) { 223 // logical block is before EOF 224 map_bh(bh, inode->i_sb, phys); 225 } else if ( create ) { 226 // to be done. 227 } 228 return 0; 229 } 230 231 unsigned long qnx4_block_map( struct inode *inode, long iblock ) 232 { 233 int ix; 234 long offset, i_xblk; 235 unsigned long block = 0; 236 struct buffer_head *bh = NULL; 237 struct qnx4_xblk *xblk = NULL; 238 struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode); 239 qnx4_nxtnt_t nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts); 240 241 if ( iblock < le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size) ) { 242 // iblock is in the first extent. This is easy. 243 block = le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_blk) + iblock - 1; 244 } else { 245 // iblock is beyond first extent. We have to follow the extent chain. 246 i_xblk = le32_to_cpu(qnx4_inode->di_xblk); 247 offset = iblock - le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size); 248 ix = 0; 249 while ( --nxtnt > 0 ) { 250 if ( ix == 0 ) { 251 // read next xtnt block. 252 bh = sb_bread(inode->i_sb, i_xblk - 1); 253 if ( !bh ) { 254 QNX4DEBUG(("qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1)); 255 return -EIO; 256 } 257 xblk = (struct qnx4_xblk*)bh->b_data; 258 if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) { 259 QNX4DEBUG(("qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk)); 260 return -EIO; 261 } 262 } 263 if ( offset < le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size) ) { 264 // got it! 265 block = le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_blk) + offset - 1; 266 break; 267 } 268 offset -= le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size); 269 if ( ++ix >= xblk->xblk_num_xtnts ) { 270 i_xblk = le32_to_cpu(xblk->xblk_next_xblk); 271 ix = 0; 272 brelse( bh ); 273 bh = NULL; 274 } 275 } 276 if ( bh ) 277 brelse( bh ); 278 } 279 280 QNX4DEBUG(("qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block)); 281 return block; 282 } 283 284 static int qnx4_statfs(struct super_block *sb, struct kstatfs *buf) 285 { 286 lock_kernel(); 287 288 buf->f_type = sb->s_magic; 289 buf->f_bsize = sb->s_blocksize; 290 buf->f_blocks = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8; 291 buf->f_bfree = qnx4_count_free_blocks(sb); 292 buf->f_bavail = buf->f_bfree; 293 buf->f_namelen = QNX4_NAME_MAX; 294 295 unlock_kernel(); 296 297 return 0; 298 } 299 300 /* 301 * Check the root directory of the filesystem to make sure 302 * it really _is_ a qnx4 filesystem, and to check the size 303 * of the directory entry. 304 */ 305 static const char *qnx4_checkroot(struct super_block *sb) 306 { 307 struct buffer_head *bh; 308 struct qnx4_inode_entry *rootdir; 309 int rd, rl; 310 int i, j; 311 int found = 0; 312 313 if (*(qnx4_sb(sb)->sb->RootDir.di_fname) != '/') { 314 return "no qnx4 filesystem (no root dir)."; 315 } else { 316 QNX4DEBUG(("QNX4 filesystem found on dev %s.\n", sb->s_id)); 317 rd = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_blk) - 1; 318 rl = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_size); 319 for (j = 0; j < rl; j++) { 320 bh = sb_bread(sb, rd + j); /* root dir, first block */ 321 if (bh == NULL) { 322 return "unable to read root entry."; 323 } 324 for (i = 0; i < QNX4_INODES_PER_BLOCK; i++) { 325 rootdir = (struct qnx4_inode_entry *) (bh->b_data + i * QNX4_DIR_ENTRY_SIZE); 326 if (rootdir->di_fname != NULL) { 327 QNX4DEBUG(("Rootdir entry found : [%s]\n", rootdir->di_fname)); 328 if (!strncmp(rootdir->di_fname, QNX4_BMNAME, sizeof QNX4_BMNAME)) { 329 found = 1; 330 qnx4_sb(sb)->BitMap = kmalloc( sizeof( struct qnx4_inode_entry ), GFP_KERNEL ); 331 if (!qnx4_sb(sb)->BitMap) { 332 brelse (bh); 333 return "not enough memory for bitmap inode"; 334 } 335 memcpy( qnx4_sb(sb)->BitMap, rootdir, sizeof( struct qnx4_inode_entry ) ); /* keep bitmap inode known */ 336 break; 337 } 338 } 339 } 340 brelse(bh); 341 if (found != 0) { 342 break; 343 } 344 } 345 if (found == 0) { 346 return "bitmap file not found."; 347 } 348 } 349 return NULL; 350 } 351 352 static int qnx4_fill_super(struct super_block *s, void *data, int silent) 353 { 354 struct buffer_head *bh; 355 struct inode *root; 356 const char *errmsg; 357 struct qnx4_sb_info *qs; 358 359 qs = kmalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL); 360 if (!qs) 361 return -ENOMEM; 362 s->s_fs_info = qs; 363 memset(qs, 0, sizeof(struct qnx4_sb_info)); 364 365 sb_set_blocksize(s, QNX4_BLOCK_SIZE); 366 367 /* Check the superblock signature. Since the qnx4 code is 368 dangerous, we should leave as quickly as possible 369 if we don't belong here... */ 370 bh = sb_bread(s, 1); 371 if (!bh) { 372 printk("qnx4: unable to read the superblock\n"); 373 goto outnobh; 374 } 375 if ( le32_to_cpu( *(__u32*)bh->b_data ) != QNX4_SUPER_MAGIC ) { 376 if (!silent) 377 printk("qnx4: wrong fsid in superblock.\n"); 378 goto out; 379 } 380 s->s_op = &qnx4_sops; 381 s->s_magic = QNX4_SUPER_MAGIC; 382 #ifndef CONFIG_QNX4FS_RW 383 s->s_flags |= MS_RDONLY; /* Yup, read-only yet */ 384 #endif 385 qnx4_sb(s)->sb_buf = bh; 386 qnx4_sb(s)->sb = (struct qnx4_super_block *) bh->b_data; 387 388 389 /* check before allocating dentries, inodes, .. */ 390 errmsg = qnx4_checkroot(s); 391 if (errmsg != NULL) { 392 if (!silent) 393 printk("qnx4: %s\n", errmsg); 394 goto out; 395 } 396 397 /* does root not have inode number QNX4_ROOT_INO ?? */ 398 root = iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK); 399 if (!root) { 400 printk("qnx4: get inode failed\n"); 401 goto out; 402 } 403 404 s->s_root = d_alloc_root(root); 405 if (s->s_root == NULL) 406 goto outi; 407 408 brelse(bh); 409 410 return 0; 411 412 outi: 413 iput(root); 414 out: 415 brelse(bh); 416 outnobh: 417 kfree(qs); 418 s->s_fs_info = NULL; 419 return -EINVAL; 420 } 421 422 static void qnx4_put_super(struct super_block *sb) 423 { 424 struct qnx4_sb_info *qs = qnx4_sb(sb); 425 kfree( qs->BitMap ); 426 kfree( qs ); 427 sb->s_fs_info = NULL; 428 return; 429 } 430 431 static int qnx4_writepage(struct page *page, struct writeback_control *wbc) 432 { 433 return block_write_full_page(page,qnx4_get_block, wbc); 434 } 435 static int qnx4_readpage(struct file *file, struct page *page) 436 { 437 return block_read_full_page(page,qnx4_get_block); 438 } 439 static int qnx4_prepare_write(struct file *file, struct page *page, 440 unsigned from, unsigned to) 441 { 442 struct qnx4_inode_info *qnx4_inode = qnx4_i(page->mapping->host); 443 return cont_prepare_write(page, from, to, qnx4_get_block, 444 &qnx4_inode->mmu_private); 445 } 446 static sector_t qnx4_bmap(struct address_space *mapping, sector_t block) 447 { 448 return generic_block_bmap(mapping,block,qnx4_get_block); 449 } 450 static struct address_space_operations qnx4_aops = { 451 .readpage = qnx4_readpage, 452 .writepage = qnx4_writepage, 453 .sync_page = block_sync_page, 454 .prepare_write = qnx4_prepare_write, 455 .commit_write = generic_commit_write, 456 .bmap = qnx4_bmap 457 }; 458 459 static void qnx4_read_inode(struct inode *inode) 460 { 461 struct buffer_head *bh; 462 struct qnx4_inode_entry *raw_inode; 463 int block, ino; 464 struct super_block *sb = inode->i_sb; 465 struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode); 466 467 ino = inode->i_ino; 468 inode->i_mode = 0; 469 470 QNX4DEBUG(("Reading inode : [%d]\n", ino)); 471 if (!ino) { 472 printk("qnx4: bad inode number on dev %s: %d is out of range\n", 473 sb->s_id, ino); 474 return; 475 } 476 block = ino / QNX4_INODES_PER_BLOCK; 477 478 if (!(bh = sb_bread(sb, block))) { 479 printk("qnx4: major problem: unable to read inode from dev " 480 "%s\n", sb->s_id); 481 return; 482 } 483 raw_inode = ((struct qnx4_inode_entry *) bh->b_data) + 484 (ino % QNX4_INODES_PER_BLOCK); 485 486 inode->i_mode = le16_to_cpu(raw_inode->di_mode); 487 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->di_uid); 488 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->di_gid); 489 inode->i_nlink = le16_to_cpu(raw_inode->di_nlink); 490 inode->i_size = le32_to_cpu(raw_inode->di_size); 491 inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->di_mtime); 492 inode->i_mtime.tv_nsec = 0; 493 inode->i_atime.tv_sec = le32_to_cpu(raw_inode->di_atime); 494 inode->i_atime.tv_nsec = 0; 495 inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->di_ctime); 496 inode->i_ctime.tv_nsec = 0; 497 inode->i_blocks = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size); 498 inode->i_blksize = QNX4_DIR_ENTRY_SIZE; 499 500 memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE); 501 if (S_ISREG(inode->i_mode)) { 502 inode->i_op = &qnx4_file_inode_operations; 503 inode->i_fop = &qnx4_file_operations; 504 inode->i_mapping->a_ops = &qnx4_aops; 505 qnx4_i(inode)->mmu_private = inode->i_size; 506 } else if (S_ISDIR(inode->i_mode)) { 507 inode->i_op = &qnx4_dir_inode_operations; 508 inode->i_fop = &qnx4_dir_operations; 509 } else if (S_ISLNK(inode->i_mode)) { 510 inode->i_op = &page_symlink_inode_operations; 511 inode->i_mapping->a_ops = &qnx4_aops; 512 qnx4_i(inode)->mmu_private = inode->i_size; 513 } else 514 printk("qnx4: bad inode %d on dev %s\n",ino,sb->s_id); 515 brelse(bh); 516 } 517 518 static kmem_cache_t *qnx4_inode_cachep; 519 520 static struct inode *qnx4_alloc_inode(struct super_block *sb) 521 { 522 struct qnx4_inode_info *ei; 523 ei = kmem_cache_alloc(qnx4_inode_cachep, SLAB_KERNEL); 524 if (!ei) 525 return NULL; 526 return &ei->vfs_inode; 527 } 528 529 static void qnx4_destroy_inode(struct inode *inode) 530 { 531 kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode)); 532 } 533 534 static void init_once(void *foo, kmem_cache_t * cachep, 535 unsigned long flags) 536 { 537 struct qnx4_inode_info *ei = (struct qnx4_inode_info *) foo; 538 539 if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) == 540 SLAB_CTOR_CONSTRUCTOR) 541 inode_init_once(&ei->vfs_inode); 542 } 543 544 static int init_inodecache(void) 545 { 546 qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache", 547 sizeof(struct qnx4_inode_info), 548 0, SLAB_RECLAIM_ACCOUNT, 549 init_once, NULL); 550 if (qnx4_inode_cachep == NULL) 551 return -ENOMEM; 552 return 0; 553 } 554 555 static void destroy_inodecache(void) 556 { 557 if (kmem_cache_destroy(qnx4_inode_cachep)) 558 printk(KERN_INFO 559 "qnx4_inode_cache: not all structures were freed\n"); 560 } 561 562 static struct super_block *qnx4_get_sb(struct file_system_type *fs_type, 563 int flags, const char *dev_name, void *data) 564 { 565 return get_sb_bdev(fs_type, flags, dev_name, data, qnx4_fill_super); 566 } 567 568 static struct file_system_type qnx4_fs_type = { 569 .owner = THIS_MODULE, 570 .name = "qnx4", 571 .get_sb = qnx4_get_sb, 572 .kill_sb = kill_block_super, 573 .fs_flags = FS_REQUIRES_DEV, 574 }; 575 576 static int __init init_qnx4_fs(void) 577 { 578 int err; 579 580 err = init_inodecache(); 581 if (err) 582 return err; 583 584 err = register_filesystem(&qnx4_fs_type); 585 if (err) { 586 destroy_inodecache(); 587 return err; 588 } 589 590 printk("QNX4 filesystem 0.2.3 registered.\n"); 591 return 0; 592 } 593 594 static void __exit exit_qnx4_fs(void) 595 { 596 unregister_filesystem(&qnx4_fs_type); 597 destroy_inodecache(); 598 } 599 600 module_init(init_qnx4_fs) 601 module_exit(exit_qnx4_fs) 602 MODULE_LICENSE("GPL"); 603 604