2 * QNX6 file system, Linux implementation.
9 * 16-02-2012 pagemap extension by Al Viro
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/slab.h>
16 #include <linux/highuid.h>
17 #include <linux/pagemap.h>
18 #include <linux/buffer_head.h>
19 #include <linux/writeback.h>
20 #include <linux/statfs.h>
21 #include <linux/parser.h>
22 #include <linux/seq_file.h>
23 #include <linux/mount.h>
24 #include <linux/crc32.h>
25 #include <linux/mpage.h>
28 static const struct super_operations qnx6_sops;
30 static void qnx6_put_super(struct super_block *sb);
31 static struct inode *qnx6_alloc_inode(struct super_block *sb);
32 static void qnx6_destroy_inode(struct inode *inode);
33 static int qnx6_remount(struct super_block *sb, int *flags, char *data);
34 static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf);
35 static int qnx6_show_options(struct seq_file *seq, struct dentry *root);
37 static const struct super_operations qnx6_sops = {
38 .alloc_inode = qnx6_alloc_inode,
39 .destroy_inode = qnx6_destroy_inode,
40 .put_super = qnx6_put_super,
41 .statfs = qnx6_statfs,
42 .remount_fs = qnx6_remount,
43 .show_options = qnx6_show_options,
46 static int qnx6_show_options(struct seq_file *seq, struct dentry *root)
48 struct super_block *sb = root->d_sb;
49 struct qnx6_sb_info *sbi = QNX6_SB(sb);
51 if (sbi->s_mount_opt & QNX6_MOUNT_MMI_FS)
52 seq_puts(seq, ",mmi_fs");
56 static int qnx6_remount(struct super_block *sb, int *flags, char *data)
63 static unsigned qnx6_get_devblock(struct super_block *sb, __fs32 block)
65 struct qnx6_sb_info *sbi = QNX6_SB(sb);
66 return fs32_to_cpu(sbi, block) + sbi->s_blks_off;
69 static unsigned qnx6_block_map(struct inode *inode, unsigned iblock);
71 static int qnx6_get_block(struct inode *inode, sector_t iblock,
72 struct buffer_head *bh, int create)
76 QNX6DEBUG((KERN_INFO "qnx6: qnx6_get_block inode=[%ld] iblock=[%ld]\n",
77 inode->i_ino, (unsigned long)iblock));
79 phys = qnx6_block_map(inode, iblock);
81 /* logical block is before EOF */
82 map_bh(bh, inode->i_sb, phys);
87 static int qnx6_check_blockptr(__fs32 ptr)
89 if (ptr == ~(__fs32)0) {
90 printk(KERN_ERR "qnx6: hit unused blockpointer.\n");
96 static int qnx6_readpage(struct file *file, struct page *page)
98 return mpage_readpage(page, qnx6_get_block);
101 static int qnx6_readpages(struct file *file, struct address_space *mapping,
102 struct list_head *pages, unsigned nr_pages)
104 return mpage_readpages(mapping, pages, nr_pages, qnx6_get_block);
108 * returns the block number for the no-th element in the tree
109 * inodebits requred as there are multiple inodes in one inode block
111 static unsigned qnx6_block_map(struct inode *inode, unsigned no)
113 struct super_block *s = inode->i_sb;
114 struct qnx6_sb_info *sbi = QNX6_SB(s);
115 struct qnx6_inode_info *ei = QNX6_I(inode);
117 struct buffer_head *bh;
120 int ptrbits = sbi->s_ptrbits;
122 u32 mask = (1 << ptrbits) - 1;
123 int depth = ei->di_filelevels;
126 bitdelta = ptrbits * depth;
127 levelptr = no >> bitdelta;
129 if (levelptr > QNX6_NO_DIRECT_POINTERS - 1) {
130 printk(KERN_ERR "qnx6:Requested file block number (%u) too big.",
135 block = qnx6_get_devblock(s, ei->di_block_ptr[levelptr]);
137 for (i = 0; i < depth; i++) {
138 bh = sb_bread(s, block);
140 printk(KERN_ERR "qnx6:Error reading block (%u)\n",
145 levelptr = (no >> bitdelta) & mask;
146 ptr = ((__fs32 *)bh->b_data)[levelptr];
148 if (!qnx6_check_blockptr(ptr))
151 block = qnx6_get_devblock(s, ptr);
157 static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf)
159 struct super_block *sb = dentry->d_sb;
160 struct qnx6_sb_info *sbi = QNX6_SB(sb);
161 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
163 buf->f_type = sb->s_magic;
164 buf->f_bsize = sb->s_blocksize;
165 buf->f_blocks = fs32_to_cpu(sbi, sbi->sb->sb_num_blocks);
166 buf->f_bfree = fs32_to_cpu(sbi, sbi->sb->sb_free_blocks);
167 buf->f_files = fs32_to_cpu(sbi, sbi->sb->sb_num_inodes);
168 buf->f_ffree = fs32_to_cpu(sbi, sbi->sb->sb_free_inodes);
169 buf->f_bavail = buf->f_bfree;
170 buf->f_namelen = QNX6_LONG_NAME_MAX;
171 buf->f_fsid.val[0] = (u32)id;
172 buf->f_fsid.val[1] = (u32)(id >> 32);
178 * Check the root directory of the filesystem to make sure
179 * it really _is_ a qnx6 filesystem, and to check the size
180 * of the directory entry.
182 static const char *qnx6_checkroot(struct super_block *s)
184 static char match_root[2][3] = {".\0\0", "..\0"};
186 struct qnx6_dir_entry *dir_entry;
187 struct inode *root = s->s_root->d_inode;
188 struct address_space *mapping = root->i_mapping;
189 struct page *page = read_mapping_page(mapping, 0, NULL);
191 return "error reading root directory";
193 dir_entry = page_address(page);
194 for (i = 0; i < 2; i++) {
195 /* maximum 3 bytes - due to match_root limitation */
196 if (strncmp(dir_entry[i].de_fname, match_root[i], 3))
201 return "error reading root directory.";
205 #ifdef CONFIG_QNX6FS_DEBUG
206 void qnx6_superblock_debug(struct qnx6_super_block *sb, struct super_block *s)
208 struct qnx6_sb_info *sbi = QNX6_SB(s);
210 QNX6DEBUG((KERN_INFO "magic: %08x\n",
211 fs32_to_cpu(sbi, sb->sb_magic)));
212 QNX6DEBUG((KERN_INFO "checksum: %08x\n",
213 fs32_to_cpu(sbi, sb->sb_checksum)));
214 QNX6DEBUG((KERN_INFO "serial: %llx\n",
215 fs64_to_cpu(sbi, sb->sb_serial)));
216 QNX6DEBUG((KERN_INFO "flags: %08x\n",
217 fs32_to_cpu(sbi, sb->sb_flags)));
218 QNX6DEBUG((KERN_INFO "blocksize: %08x\n",
219 fs32_to_cpu(sbi, sb->sb_blocksize)));
220 QNX6DEBUG((KERN_INFO "num_inodes: %08x\n",
221 fs32_to_cpu(sbi, sb->sb_num_inodes)));
222 QNX6DEBUG((KERN_INFO "free_inodes: %08x\n",
223 fs32_to_cpu(sbi, sb->sb_free_inodes)));
224 QNX6DEBUG((KERN_INFO "num_blocks: %08x\n",
225 fs32_to_cpu(sbi, sb->sb_num_blocks)));
226 QNX6DEBUG((KERN_INFO "free_blocks: %08x\n",
227 fs32_to_cpu(sbi, sb->sb_free_blocks)));
228 QNX6DEBUG((KERN_INFO "inode_levels: %02x\n",
238 static const match_table_t tokens = {
239 {Opt_mmifs, "mmi_fs"},
243 static int qnx6_parse_options(char *options, struct super_block *sb)
246 struct qnx6_sb_info *sbi = QNX6_SB(sb);
247 substring_t args[MAX_OPT_ARGS];
252 while ((p = strsep(&options, ",")) != NULL) {
257 token = match_token(p, tokens, args);
260 set_opt(sbi->s_mount_opt, MMI_FS);
269 static struct buffer_head *qnx6_check_first_superblock(struct super_block *s,
270 int offset, int silent)
272 struct qnx6_sb_info *sbi = QNX6_SB(s);
273 struct buffer_head *bh;
274 struct qnx6_super_block *sb;
276 /* Check the superblock signatures
277 start with the first superblock */
278 bh = sb_bread(s, offset);
280 printk(KERN_ERR "qnx6: unable to read the first superblock\n");
283 sb = (struct qnx6_super_block *)bh->b_data;
284 if (fs32_to_cpu(sbi, sb->sb_magic) != QNX6_SUPER_MAGIC) {
285 sbi->s_bytesex = BYTESEX_BE;
286 if (fs32_to_cpu(sbi, sb->sb_magic) == QNX6_SUPER_MAGIC) {
287 /* we got a big endian fs */
288 QNX6DEBUG((KERN_INFO "qnx6: fs got different"
292 sbi->s_bytesex = BYTESEX_LE;
295 printk(KERN_ERR "qnx6: wrong signature (magic)"
296 " in superblock #1.\n");
298 printk(KERN_INFO "qnx6: wrong signature (magic)"
299 " at position (0x%lx) - will try"
300 " alternative position (0x0000).\n",
301 offset * s->s_blocksize);
310 static struct inode *qnx6_private_inode(struct super_block *s,
311 struct qnx6_root_node *p);
313 static int qnx6_fill_super(struct super_block *s, void *data, int silent)
315 struct buffer_head *bh1 = NULL, *bh2 = NULL;
316 struct qnx6_super_block *sb1 = NULL, *sb2 = NULL;
317 struct qnx6_sb_info *sbi;
320 struct qnx6_sb_info *qs;
323 int bootblock_offset = QNX6_BOOTBLOCK_SIZE;
325 qs = kzalloc(sizeof(struct qnx6_sb_info), GFP_KERNEL);
330 /* Superblock always is 512 Byte long */
331 if (!sb_set_blocksize(s, QNX6_SUPERBLOCK_SIZE)) {
332 printk(KERN_ERR "qnx6: unable to set blocksize\n");
336 /* parse the mount-options */
337 if (!qnx6_parse_options((char *) data, s)) {
338 printk(KERN_ERR "qnx6: invalid mount options.\n");
341 if (test_opt(s, MMI_FS)) {
342 sb1 = qnx6_mmi_fill_super(s, silent);
349 sbi->s_bytesex = BYTESEX_LE;
350 /* Check the superblock signatures
351 start with the first superblock */
352 bh1 = qnx6_check_first_superblock(s,
353 bootblock_offset / QNX6_SUPERBLOCK_SIZE, silent);
355 /* try again without bootblock offset */
356 bh1 = qnx6_check_first_superblock(s, 0, silent);
358 printk(KERN_ERR "qnx6: unable to read the first superblock\n");
361 /* seems that no bootblock at partition start */
362 bootblock_offset = 0;
364 sb1 = (struct qnx6_super_block *)bh1->b_data;
366 #ifdef CONFIG_QNX6FS_DEBUG
367 qnx6_superblock_debug(sb1, s);
370 /* checksum check - start at byte 8 and end at byte 512 */
371 if (fs32_to_cpu(sbi, sb1->sb_checksum) !=
372 crc32_be(0, (char *)(bh1->b_data + 8), 504)) {
373 printk(KERN_ERR "qnx6: superblock #1 checksum error\n");
377 /* set new blocksize */
378 if (!sb_set_blocksize(s, fs32_to_cpu(sbi, sb1->sb_blocksize))) {
379 printk(KERN_ERR "qnx6: unable to set blocksize\n");
382 /* blocksize invalidates bh - pull it back in */
384 bh1 = sb_bread(s, bootblock_offset >> s->s_blocksize_bits);
387 sb1 = (struct qnx6_super_block *)bh1->b_data;
389 /* calculate second superblock blocknumber */
390 offset = fs32_to_cpu(sbi, sb1->sb_num_blocks) +
391 (bootblock_offset >> s->s_blocksize_bits) +
392 (QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits);
394 /* set bootblock offset */
395 sbi->s_blks_off = (bootblock_offset >> s->s_blocksize_bits) +
396 (QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits);
398 /* next the second superblock */
399 bh2 = sb_bread(s, offset);
401 printk(KERN_ERR "qnx6: unable to read the second superblock\n");
404 sb2 = (struct qnx6_super_block *)bh2->b_data;
405 if (fs32_to_cpu(sbi, sb2->sb_magic) != QNX6_SUPER_MAGIC) {
407 printk(KERN_ERR "qnx6: wrong signature (magic)"
408 " in superblock #2.\n");
412 /* checksum check - start at byte 8 and end at byte 512 */
413 if (fs32_to_cpu(sbi, sb2->sb_checksum) !=
414 crc32_be(0, (char *)(bh2->b_data + 8), 504)) {
415 printk(KERN_ERR "qnx6: superblock #2 checksum error\n");
419 if (fs64_to_cpu(sbi, sb1->sb_serial) >=
420 fs64_to_cpu(sbi, sb2->sb_serial)) {
421 /* superblock #1 active */
423 sbi->sb = (struct qnx6_super_block *)bh1->b_data;
425 printk(KERN_INFO "qnx6: superblock #1 active\n");
427 /* superblock #2 active */
429 sbi->sb = (struct qnx6_super_block *)bh2->b_data;
431 printk(KERN_INFO "qnx6: superblock #2 active\n");
434 /* sanity check - limit maximum indirect pointer levels */
435 if (sb1->Inode.levels > QNX6_PTR_MAX_LEVELS) {
436 printk(KERN_ERR "qnx6: too many inode levels (max %i, sb %i)\n",
437 QNX6_PTR_MAX_LEVELS, sb1->Inode.levels);
440 if (sb1->Longfile.levels > QNX6_PTR_MAX_LEVELS) {
441 printk(KERN_ERR "qnx6: too many longfilename levels"
442 " (max %i, sb %i)\n",
443 QNX6_PTR_MAX_LEVELS, sb1->Longfile.levels);
446 s->s_op = &qnx6_sops;
447 s->s_magic = QNX6_SUPER_MAGIC;
448 s->s_flags |= MS_RDONLY; /* Yup, read-only yet */
450 /* ease the later tree level calculations */
452 sbi->s_ptrbits = ilog2(s->s_blocksize / 4);
453 sbi->inodes = qnx6_private_inode(s, &sb1->Inode);
456 sbi->longfile = qnx6_private_inode(s, &sb1->Longfile);
460 /* prefetch root inode */
461 root = qnx6_iget(s, QNX6_ROOT_INO);
463 printk(KERN_ERR "qnx6: get inode failed\n");
469 s->s_root = d_make_root(root);
474 errmsg = qnx6_checkroot(s);
475 if (errmsg != NULL) {
477 printk(KERN_ERR "qnx6: %s\n", errmsg);
500 static void qnx6_put_super(struct super_block *sb)
502 struct qnx6_sb_info *qs = QNX6_SB(sb);
507 sb->s_fs_info = NULL;
511 static sector_t qnx6_bmap(struct address_space *mapping, sector_t block)
513 return generic_block_bmap(mapping, block, qnx6_get_block);
515 static const struct address_space_operations qnx6_aops = {
516 .readpage = qnx6_readpage,
517 .readpages = qnx6_readpages,
521 static struct inode *qnx6_private_inode(struct super_block *s,
522 struct qnx6_root_node *p)
524 struct inode *inode = new_inode(s);
526 struct qnx6_inode_info *ei = QNX6_I(inode);
527 struct qnx6_sb_info *sbi = QNX6_SB(s);
528 inode->i_size = fs64_to_cpu(sbi, p->size);
529 memcpy(ei->di_block_ptr, p->ptr, sizeof(p->ptr));
530 ei->di_filelevels = p->levels;
531 inode->i_mode = S_IFREG | S_IRUSR; /* probably wrong */
532 inode->i_mapping->a_ops = &qnx6_aops;
537 struct inode *qnx6_iget(struct super_block *sb, unsigned ino)
539 struct qnx6_sb_info *sbi = QNX6_SB(sb);
540 struct qnx6_inode_entry *raw_inode;
542 struct qnx6_inode_info *ei;
543 struct address_space *mapping;
547 inode = iget_locked(sb, ino);
549 return ERR_PTR(-ENOMEM);
550 if (!(inode->i_state & I_NEW))
558 printk(KERN_ERR "qnx6: bad inode number on dev %s: %u is "
562 return ERR_PTR(-EIO);
564 n = (ino - 1) >> (PAGE_CACHE_SHIFT - QNX6_INODE_SIZE_BITS);
565 offs = (ino - 1) & (~PAGE_CACHE_MASK >> QNX6_INODE_SIZE_BITS);
566 mapping = sbi->inodes->i_mapping;
567 page = read_mapping_page(mapping, n, NULL);
569 printk(KERN_ERR "qnx6: major problem: unable to read inode from "
570 "dev %s\n", sb->s_id);
572 return ERR_CAST(page);
575 raw_inode = ((struct qnx6_inode_entry *)page_address(page)) + offs;
577 inode->i_mode = fs16_to_cpu(sbi, raw_inode->di_mode);
578 i_uid_write(inode, (uid_t)fs32_to_cpu(sbi, raw_inode->di_uid));
579 i_gid_write(inode, (gid_t)fs32_to_cpu(sbi, raw_inode->di_gid));
580 inode->i_size = fs64_to_cpu(sbi, raw_inode->di_size);
581 inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_mtime);
582 inode->i_mtime.tv_nsec = 0;
583 inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_atime);
584 inode->i_atime.tv_nsec = 0;
585 inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_ctime);
586 inode->i_ctime.tv_nsec = 0;
588 /* calc blocks based on 512 byte blocksize */
589 inode->i_blocks = (inode->i_size + 511) >> 9;
591 memcpy(&ei->di_block_ptr, &raw_inode->di_block_ptr,
592 sizeof(raw_inode->di_block_ptr));
593 ei->di_filelevels = raw_inode->di_filelevels;
595 if (S_ISREG(inode->i_mode)) {
596 inode->i_fop = &generic_ro_fops;
597 inode->i_mapping->a_ops = &qnx6_aops;
598 } else if (S_ISDIR(inode->i_mode)) {
599 inode->i_op = &qnx6_dir_inode_operations;
600 inode->i_fop = &qnx6_dir_operations;
601 inode->i_mapping->a_ops = &qnx6_aops;
602 } else if (S_ISLNK(inode->i_mode)) {
603 inode->i_op = &page_symlink_inode_operations;
604 inode->i_mapping->a_ops = &qnx6_aops;
606 init_special_inode(inode, inode->i_mode, 0);
608 unlock_new_inode(inode);
612 static struct kmem_cache *qnx6_inode_cachep;
614 static struct inode *qnx6_alloc_inode(struct super_block *sb)
616 struct qnx6_inode_info *ei;
617 ei = kmem_cache_alloc(qnx6_inode_cachep, GFP_KERNEL);
620 return &ei->vfs_inode;
623 static void qnx6_i_callback(struct rcu_head *head)
625 struct inode *inode = container_of(head, struct inode, i_rcu);
626 kmem_cache_free(qnx6_inode_cachep, QNX6_I(inode));
629 static void qnx6_destroy_inode(struct inode *inode)
631 call_rcu(&inode->i_rcu, qnx6_i_callback);
634 static void init_once(void *foo)
636 struct qnx6_inode_info *ei = (struct qnx6_inode_info *) foo;
638 inode_init_once(&ei->vfs_inode);
641 static int init_inodecache(void)
643 qnx6_inode_cachep = kmem_cache_create("qnx6_inode_cache",
644 sizeof(struct qnx6_inode_info),
645 0, (SLAB_RECLAIM_ACCOUNT|
648 if (!qnx6_inode_cachep)
653 static void destroy_inodecache(void)
656 * Make sure all delayed rcu free inodes are flushed before we
660 kmem_cache_destroy(qnx6_inode_cachep);
663 static struct dentry *qnx6_mount(struct file_system_type *fs_type,
664 int flags, const char *dev_name, void *data)
666 return mount_bdev(fs_type, flags, dev_name, data, qnx6_fill_super);
669 static struct file_system_type qnx6_fs_type = {
670 .owner = THIS_MODULE,
673 .kill_sb = kill_block_super,
674 .fs_flags = FS_REQUIRES_DEV,
676 MODULE_ALIAS_FS("qnx6");
678 static int __init init_qnx6_fs(void)
682 err = init_inodecache();
686 err = register_filesystem(&qnx6_fs_type);
688 destroy_inodecache();
692 printk(KERN_INFO "QNX6 filesystem 1.0.0 registered.\n");
696 static void __exit exit_qnx6_fs(void)
698 unregister_filesystem(&qnx6_fs_type);
699 destroy_inodecache();
702 module_init(init_qnx6_fs)
703 module_exit(exit_qnx6_fs)
704 MODULE_LICENSE("GPL");