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/module.h> 16 #include <linux/init.h> 17 #include <linux/slab.h> 18 #include <linux/highuid.h> 19 #include <linux/smp_lock.h> 20 #include <linux/pagemap.h> 21 #include <linux/buffer_head.h> 22 #include <linux/writeback.h> 23 #include <linux/statfs.h> 24 #include "qnx4.h" 25 26 #define QNX4_VERSION 4 27 #define QNX4_BMNAME ".bitmap" 28 29 static const struct super_operations qnx4_sops; 30 31 #ifdef CONFIG_QNX4FS_RW 32 33 static void qnx4_delete_inode(struct inode *inode) 34 { 35 QNX4DEBUG(("qnx4: deleting inode [%lu]\n", (unsigned long) inode->i_ino)); 36 truncate_inode_pages(&inode->i_data, 0); 37 inode->i_size = 0; 38 qnx4_truncate(inode); 39 lock_kernel(); 40 qnx4_free_inode(inode); 41 unlock_kernel(); 42 } 43 44 static int qnx4_write_inode(struct inode *inode, int do_sync) 45 { 46 struct qnx4_inode_entry *raw_inode; 47 int block, ino; 48 struct buffer_head *bh; 49 ino = inode->i_ino; 50 51 QNX4DEBUG(("qnx4: write inode 1.\n")); 52 if (inode->i_nlink == 0) { 53 return 0; 54 } 55 if (!ino) { 56 printk("qnx4: bad inode number on dev %s: %d is out of range\n", 57 inode->i_sb->s_id, ino); 58 return -EIO; 59 } 60 QNX4DEBUG(("qnx4: write inode 2.\n")); 61 block = ino / QNX4_INODES_PER_BLOCK; 62 lock_kernel(); 63 if (!(bh = sb_bread(inode->i_sb, block))) { 64 printk("qnx4: major problem: unable to read inode from dev " 65 "%s\n", inode->i_sb->s_id); 66 unlock_kernel(); 67 return -EIO; 68 } 69 raw_inode = ((struct qnx4_inode_entry *) bh->b_data) + 70 (ino % QNX4_INODES_PER_BLOCK); 71 raw_inode->di_mode = cpu_to_le16(inode->i_mode); 72 raw_inode->di_uid = cpu_to_le16(fs_high2lowuid(inode->i_uid)); 73 raw_inode->di_gid = cpu_to_le16(fs_high2lowgid(inode->i_gid)); 74 raw_inode->di_nlink = cpu_to_le16(inode->i_nlink); 75 raw_inode->di_size = cpu_to_le32(inode->i_size); 76 raw_inode->di_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 77 raw_inode->di_atime = cpu_to_le32(inode->i_atime.tv_sec); 78 raw_inode->di_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 79 raw_inode->di_first_xtnt.xtnt_size = cpu_to_le32(inode->i_blocks); 80 mark_buffer_dirty(bh); 81 if (do_sync) { 82 sync_dirty_buffer(bh); 83 if (buffer_req(bh) && !buffer_uptodate(bh)) { 84 printk("qnx4: IO error syncing inode [%s:%08x]\n", 85 inode->i_sb->s_id, ino); 86 brelse(bh); 87 unlock_kernel(); 88 return -EIO; 89 } 90 } 91 brelse(bh); 92 unlock_kernel(); 93 return 0; 94 } 95 96 #endif 97 98 static void qnx4_put_super(struct super_block *sb); 99 static struct inode *qnx4_alloc_inode(struct super_block *sb); 100 static void qnx4_destroy_inode(struct inode *inode); 101 static int qnx4_remount(struct super_block *sb, int *flags, char *data); 102 static int qnx4_statfs(struct dentry *, struct kstatfs *); 103 104 static const struct super_operations qnx4_sops = 105 { 106 .alloc_inode = qnx4_alloc_inode, 107 .destroy_inode = qnx4_destroy_inode, 108 .put_super = qnx4_put_super, 109 .statfs = qnx4_statfs, 110 .remount_fs = qnx4_remount, 111 #ifdef CONFIG_QNX4FS_RW 112 .write_inode = qnx4_write_inode, 113 .delete_inode = qnx4_delete_inode, 114 #endif 115 }; 116 117 static int qnx4_remount(struct super_block *sb, int *flags, char *data) 118 { 119 struct qnx4_sb_info *qs; 120 121 qs = qnx4_sb(sb); 122 qs->Version = QNX4_VERSION; 123 #ifndef CONFIG_QNX4FS_RW 124 *flags |= MS_RDONLY; 125 #endif 126 if (*flags & MS_RDONLY) { 127 return 0; 128 } 129 130 mark_buffer_dirty(qs->sb_buf); 131 132 return 0; 133 } 134 135 static struct buffer_head *qnx4_getblk(struct inode *inode, int nr, 136 int create) 137 { 138 struct buffer_head *result = NULL; 139 140 if ( nr >= 0 ) 141 nr = qnx4_block_map( inode, nr ); 142 if (nr) { 143 result = sb_getblk(inode->i_sb, nr); 144 return result; 145 } 146 if (!create) { 147 return NULL; 148 } 149 #if 0 150 tmp = qnx4_new_block(inode->i_sb); 151 if (!tmp) { 152 return NULL; 153 } 154 result = sb_getblk(inode->i_sb, tmp); 155 if (tst) { 156 qnx4_free_block(inode->i_sb, tmp); 157 brelse(result); 158 goto repeat; 159 } 160 tst = tmp; 161 #endif 162 inode->i_ctime = CURRENT_TIME_SEC; 163 mark_inode_dirty(inode); 164 return result; 165 } 166 167 struct buffer_head *qnx4_bread(struct inode *inode, int block, int create) 168 { 169 struct buffer_head *bh; 170 171 bh = qnx4_getblk(inode, block, create); 172 if (!bh || buffer_uptodate(bh)) { 173 return bh; 174 } 175 ll_rw_block(READ, 1, &bh); 176 wait_on_buffer(bh); 177 if (buffer_uptodate(bh)) { 178 return bh; 179 } 180 brelse(bh); 181 182 return NULL; 183 } 184 185 static int qnx4_get_block( struct inode *inode, sector_t iblock, struct buffer_head *bh, int create ) 186 { 187 unsigned long phys; 188 189 QNX4DEBUG(("qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock)); 190 191 phys = qnx4_block_map( inode, iblock ); 192 if ( phys ) { 193 // logical block is before EOF 194 map_bh(bh, inode->i_sb, phys); 195 } else if ( create ) { 196 // to be done. 197 } 198 return 0; 199 } 200 201 unsigned long qnx4_block_map( struct inode *inode, long iblock ) 202 { 203 int ix; 204 long offset, i_xblk; 205 unsigned long block = 0; 206 struct buffer_head *bh = NULL; 207 struct qnx4_xblk *xblk = NULL; 208 struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode); 209 u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts); 210 211 if ( iblock < le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size) ) { 212 // iblock is in the first extent. This is easy. 213 block = le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_blk) + iblock - 1; 214 } else { 215 // iblock is beyond first extent. We have to follow the extent chain. 216 i_xblk = le32_to_cpu(qnx4_inode->di_xblk); 217 offset = iblock - le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size); 218 ix = 0; 219 while ( --nxtnt > 0 ) { 220 if ( ix == 0 ) { 221 // read next xtnt block. 222 bh = sb_bread(inode->i_sb, i_xblk - 1); 223 if ( !bh ) { 224 QNX4DEBUG(("qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1)); 225 return -EIO; 226 } 227 xblk = (struct qnx4_xblk*)bh->b_data; 228 if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) { 229 QNX4DEBUG(("qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk)); 230 return -EIO; 231 } 232 } 233 if ( offset < le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size) ) { 234 // got it! 235 block = le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_blk) + offset - 1; 236 break; 237 } 238 offset -= le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size); 239 if ( ++ix >= xblk->xblk_num_xtnts ) { 240 i_xblk = le32_to_cpu(xblk->xblk_next_xblk); 241 ix = 0; 242 brelse( bh ); 243 bh = NULL; 244 } 245 } 246 if ( bh ) 247 brelse( bh ); 248 } 249 250 QNX4DEBUG(("qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block)); 251 return block; 252 } 253 254 static int qnx4_statfs(struct dentry *dentry, struct kstatfs *buf) 255 { 256 struct super_block *sb = dentry->d_sb; 257 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 258 259 lock_kernel(); 260 261 buf->f_type = sb->s_magic; 262 buf->f_bsize = sb->s_blocksize; 263 buf->f_blocks = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8; 264 buf->f_bfree = qnx4_count_free_blocks(sb); 265 buf->f_bavail = buf->f_bfree; 266 buf->f_namelen = QNX4_NAME_MAX; 267 buf->f_fsid.val[0] = (u32)id; 268 buf->f_fsid.val[1] = (u32)(id >> 32); 269 270 unlock_kernel(); 271 272 return 0; 273 } 274 275 /* 276 * Check the root directory of the filesystem to make sure 277 * it really _is_ a qnx4 filesystem, and to check the size 278 * of the directory entry. 279 */ 280 static const char *qnx4_checkroot(struct super_block *sb) 281 { 282 struct buffer_head *bh; 283 struct qnx4_inode_entry *rootdir; 284 int rd, rl; 285 int i, j; 286 int found = 0; 287 288 if (*(qnx4_sb(sb)->sb->RootDir.di_fname) != '/') { 289 return "no qnx4 filesystem (no root dir)."; 290 } else { 291 QNX4DEBUG(("QNX4 filesystem found on dev %s.\n", sb->s_id)); 292 rd = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_blk) - 1; 293 rl = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_size); 294 for (j = 0; j < rl; j++) { 295 bh = sb_bread(sb, rd + j); /* root dir, first block */ 296 if (bh == NULL) { 297 return "unable to read root entry."; 298 } 299 for (i = 0; i < QNX4_INODES_PER_BLOCK; i++) { 300 rootdir = (struct qnx4_inode_entry *) (bh->b_data + i * QNX4_DIR_ENTRY_SIZE); 301 if (rootdir->di_fname != NULL) { 302 QNX4DEBUG(("Rootdir entry found : [%s]\n", rootdir->di_fname)); 303 if (!strncmp(rootdir->di_fname, QNX4_BMNAME, sizeof QNX4_BMNAME)) { 304 found = 1; 305 qnx4_sb(sb)->BitMap = kmalloc( sizeof( struct qnx4_inode_entry ), GFP_KERNEL ); 306 if (!qnx4_sb(sb)->BitMap) { 307 brelse (bh); 308 return "not enough memory for bitmap inode"; 309 } 310 memcpy( qnx4_sb(sb)->BitMap, rootdir, sizeof( struct qnx4_inode_entry ) ); /* keep bitmap inode known */ 311 break; 312 } 313 } 314 } 315 brelse(bh); 316 if (found != 0) { 317 break; 318 } 319 } 320 if (found == 0) { 321 return "bitmap file not found."; 322 } 323 } 324 return NULL; 325 } 326 327 static int qnx4_fill_super(struct super_block *s, void *data, int silent) 328 { 329 struct buffer_head *bh; 330 struct inode *root; 331 const char *errmsg; 332 struct qnx4_sb_info *qs; 333 int ret = -EINVAL; 334 335 qs = kzalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL); 336 if (!qs) 337 return -ENOMEM; 338 s->s_fs_info = qs; 339 340 sb_set_blocksize(s, QNX4_BLOCK_SIZE); 341 342 /* Check the superblock signature. Since the qnx4 code is 343 dangerous, we should leave as quickly as possible 344 if we don't belong here... */ 345 bh = sb_bread(s, 1); 346 if (!bh) { 347 printk("qnx4: unable to read the superblock\n"); 348 goto outnobh; 349 } 350 if ( le32_to_cpup((__le32*) bh->b_data) != QNX4_SUPER_MAGIC ) { 351 if (!silent) 352 printk("qnx4: wrong fsid in superblock.\n"); 353 goto out; 354 } 355 s->s_op = &qnx4_sops; 356 s->s_magic = QNX4_SUPER_MAGIC; 357 #ifndef CONFIG_QNX4FS_RW 358 s->s_flags |= MS_RDONLY; /* Yup, read-only yet */ 359 #endif 360 qnx4_sb(s)->sb_buf = bh; 361 qnx4_sb(s)->sb = (struct qnx4_super_block *) bh->b_data; 362 363 364 /* check before allocating dentries, inodes, .. */ 365 errmsg = qnx4_checkroot(s); 366 if (errmsg != NULL) { 367 if (!silent) 368 printk("qnx4: %s\n", errmsg); 369 goto out; 370 } 371 372 /* does root not have inode number QNX4_ROOT_INO ?? */ 373 root = qnx4_iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK); 374 if (IS_ERR(root)) { 375 printk("qnx4: get inode failed\n"); 376 ret = PTR_ERR(root); 377 goto out; 378 } 379 380 ret = -ENOMEM; 381 s->s_root = d_alloc_root(root); 382 if (s->s_root == NULL) 383 goto outi; 384 385 brelse(bh); 386 387 return 0; 388 389 outi: 390 iput(root); 391 out: 392 brelse(bh); 393 outnobh: 394 kfree(qs); 395 s->s_fs_info = NULL; 396 return ret; 397 } 398 399 static void qnx4_put_super(struct super_block *sb) 400 { 401 struct qnx4_sb_info *qs = qnx4_sb(sb); 402 kfree( qs->BitMap ); 403 kfree( qs ); 404 sb->s_fs_info = NULL; 405 return; 406 } 407 408 static int qnx4_writepage(struct page *page, struct writeback_control *wbc) 409 { 410 return block_write_full_page(page,qnx4_get_block, wbc); 411 } 412 413 static int qnx4_readpage(struct file *file, struct page *page) 414 { 415 return block_read_full_page(page,qnx4_get_block); 416 } 417 418 static int qnx4_write_begin(struct file *file, struct address_space *mapping, 419 loff_t pos, unsigned len, unsigned flags, 420 struct page **pagep, void **fsdata) 421 { 422 struct qnx4_inode_info *qnx4_inode = qnx4_i(mapping->host); 423 *pagep = NULL; 424 return cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata, 425 qnx4_get_block, 426 &qnx4_inode->mmu_private); 427 } 428 static sector_t qnx4_bmap(struct address_space *mapping, sector_t block) 429 { 430 return generic_block_bmap(mapping,block,qnx4_get_block); 431 } 432 static const struct address_space_operations qnx4_aops = { 433 .readpage = qnx4_readpage, 434 .writepage = qnx4_writepage, 435 .sync_page = block_sync_page, 436 .write_begin = qnx4_write_begin, 437 .write_end = generic_write_end, 438 .bmap = qnx4_bmap 439 }; 440 441 struct inode *qnx4_iget(struct super_block *sb, unsigned long ino) 442 { 443 struct buffer_head *bh; 444 struct qnx4_inode_entry *raw_inode; 445 int block; 446 struct qnx4_inode_entry *qnx4_inode; 447 struct inode *inode; 448 449 inode = iget_locked(sb, ino); 450 if (!inode) 451 return ERR_PTR(-ENOMEM); 452 if (!(inode->i_state & I_NEW)) 453 return inode; 454 455 qnx4_inode = qnx4_raw_inode(inode); 456 inode->i_mode = 0; 457 458 QNX4DEBUG(("Reading inode : [%d]\n", ino)); 459 if (!ino) { 460 printk(KERN_ERR "qnx4: bad inode number on dev %s: %lu is " 461 "out of range\n", 462 sb->s_id, ino); 463 iget_failed(inode); 464 return ERR_PTR(-EIO); 465 } 466 block = ino / QNX4_INODES_PER_BLOCK; 467 468 if (!(bh = sb_bread(sb, block))) { 469 printk("qnx4: major problem: unable to read inode from dev " 470 "%s\n", sb->s_id); 471 iget_failed(inode); 472 return ERR_PTR(-EIO); 473 } 474 raw_inode = ((struct qnx4_inode_entry *) bh->b_data) + 475 (ino % QNX4_INODES_PER_BLOCK); 476 477 inode->i_mode = le16_to_cpu(raw_inode->di_mode); 478 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->di_uid); 479 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->di_gid); 480 inode->i_nlink = le16_to_cpu(raw_inode->di_nlink); 481 inode->i_size = le32_to_cpu(raw_inode->di_size); 482 inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->di_mtime); 483 inode->i_mtime.tv_nsec = 0; 484 inode->i_atime.tv_sec = le32_to_cpu(raw_inode->di_atime); 485 inode->i_atime.tv_nsec = 0; 486 inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->di_ctime); 487 inode->i_ctime.tv_nsec = 0; 488 inode->i_blocks = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size); 489 490 memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE); 491 if (S_ISREG(inode->i_mode)) { 492 inode->i_op = &qnx4_file_inode_operations; 493 inode->i_fop = &qnx4_file_operations; 494 inode->i_mapping->a_ops = &qnx4_aops; 495 qnx4_i(inode)->mmu_private = inode->i_size; 496 } else if (S_ISDIR(inode->i_mode)) { 497 inode->i_op = &qnx4_dir_inode_operations; 498 inode->i_fop = &qnx4_dir_operations; 499 } else if (S_ISLNK(inode->i_mode)) { 500 inode->i_op = &page_symlink_inode_operations; 501 inode->i_mapping->a_ops = &qnx4_aops; 502 qnx4_i(inode)->mmu_private = inode->i_size; 503 } else { 504 printk(KERN_ERR "qnx4: bad inode %lu on dev %s\n", 505 ino, sb->s_id); 506 iget_failed(inode); 507 brelse(bh); 508 return ERR_PTR(-EIO); 509 } 510 brelse(bh); 511 unlock_new_inode(inode); 512 return inode; 513 } 514 515 static struct kmem_cache *qnx4_inode_cachep; 516 517 static struct inode *qnx4_alloc_inode(struct super_block *sb) 518 { 519 struct qnx4_inode_info *ei; 520 ei = kmem_cache_alloc(qnx4_inode_cachep, GFP_KERNEL); 521 if (!ei) 522 return NULL; 523 return &ei->vfs_inode; 524 } 525 526 static void qnx4_destroy_inode(struct inode *inode) 527 { 528 kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode)); 529 } 530 531 static void init_once(void *foo) 532 { 533 struct qnx4_inode_info *ei = (struct qnx4_inode_info *) foo; 534 535 inode_init_once(&ei->vfs_inode); 536 } 537 538 static int init_inodecache(void) 539 { 540 qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache", 541 sizeof(struct qnx4_inode_info), 542 0, (SLAB_RECLAIM_ACCOUNT| 543 SLAB_MEM_SPREAD), 544 init_once); 545 if (qnx4_inode_cachep == NULL) 546 return -ENOMEM; 547 return 0; 548 } 549 550 static void destroy_inodecache(void) 551 { 552 kmem_cache_destroy(qnx4_inode_cachep); 553 } 554 555 static int qnx4_get_sb(struct file_system_type *fs_type, 556 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 557 { 558 return get_sb_bdev(fs_type, flags, dev_name, data, qnx4_fill_super, 559 mnt); 560 } 561 562 static struct file_system_type qnx4_fs_type = { 563 .owner = THIS_MODULE, 564 .name = "qnx4", 565 .get_sb = qnx4_get_sb, 566 .kill_sb = kill_block_super, 567 .fs_flags = FS_REQUIRES_DEV, 568 }; 569 570 static int __init init_qnx4_fs(void) 571 { 572 int err; 573 574 err = init_inodecache(); 575 if (err) 576 return err; 577 578 err = register_filesystem(&qnx4_fs_type); 579 if (err) { 580 destroy_inodecache(); 581 return err; 582 } 583 584 printk("QNX4 filesystem 0.2.3 registered.\n"); 585 return 0; 586 } 587 588 static void __exit exit_qnx4_fs(void) 589 { 590 unregister_filesystem(&qnx4_fs_type); 591 destroy_inodecache(); 592 } 593 594 module_init(init_qnx4_fs) 595 module_exit(exit_qnx4_fs) 596 MODULE_LICENSE("GPL"); 597 598