xref: /openbmc/linux/fs/qnx6/inode.c (revision 97da55fc)
1 /*
2  * QNX6 file system, Linux implementation.
3  *
4  * Version : 1.0.0
5  *
6  * History :
7  *
8  * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
9  * 16-02-2012 pagemap extension by Al Viro
10  *
11  */
12 
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>
26 #include "qnx6.h"
27 
28 static const struct super_operations qnx6_sops;
29 
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);
36 
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,
44 };
45 
46 static int qnx6_show_options(struct seq_file *seq, struct dentry *root)
47 {
48 	struct super_block *sb = root->d_sb;
49 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
50 
51 	if (sbi->s_mount_opt & QNX6_MOUNT_MMI_FS)
52 		seq_puts(seq, ",mmi_fs");
53 	return 0;
54 }
55 
56 static int qnx6_remount(struct super_block *sb, int *flags, char *data)
57 {
58 	*flags |= MS_RDONLY;
59 	return 0;
60 }
61 
62 static unsigned qnx6_get_devblock(struct super_block *sb, __fs32 block)
63 {
64 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
65 	return fs32_to_cpu(sbi, block) + sbi->s_blks_off;
66 }
67 
68 static unsigned qnx6_block_map(struct inode *inode, unsigned iblock);
69 
70 static int qnx6_get_block(struct inode *inode, sector_t iblock,
71 			struct buffer_head *bh, int create)
72 {
73 	unsigned phys;
74 
75 	QNX6DEBUG((KERN_INFO "qnx6: qnx6_get_block inode=[%ld] iblock=[%ld]\n",
76 			inode->i_ino, (unsigned long)iblock));
77 
78 	phys = qnx6_block_map(inode, iblock);
79 	if (phys) {
80 		/* logical block is before EOF */
81 		map_bh(bh, inode->i_sb, phys);
82 	}
83 	return 0;
84 }
85 
86 static int qnx6_check_blockptr(__fs32 ptr)
87 {
88 	if (ptr == ~(__fs32)0) {
89 		printk(KERN_ERR "qnx6: hit unused blockpointer.\n");
90 		return 0;
91 	}
92 	return 1;
93 }
94 
95 static int qnx6_readpage(struct file *file, struct page *page)
96 {
97 	return mpage_readpage(page, qnx6_get_block);
98 }
99 
100 static int qnx6_readpages(struct file *file, struct address_space *mapping,
101 		   struct list_head *pages, unsigned nr_pages)
102 {
103 	return mpage_readpages(mapping, pages, nr_pages, qnx6_get_block);
104 }
105 
106 /*
107  * returns the block number for the no-th element in the tree
108  * inodebits requred as there are multiple inodes in one inode block
109  */
110 static unsigned qnx6_block_map(struct inode *inode, unsigned no)
111 {
112 	struct super_block *s = inode->i_sb;
113 	struct qnx6_sb_info *sbi = QNX6_SB(s);
114 	struct qnx6_inode_info *ei = QNX6_I(inode);
115 	unsigned block = 0;
116 	struct buffer_head *bh;
117 	__fs32 ptr;
118 	int levelptr;
119 	int ptrbits = sbi->s_ptrbits;
120 	int bitdelta;
121 	u32 mask = (1 << ptrbits) - 1;
122 	int depth = ei->di_filelevels;
123 	int i;
124 
125 	bitdelta = ptrbits * depth;
126 	levelptr = no >> bitdelta;
127 
128 	if (levelptr > QNX6_NO_DIRECT_POINTERS - 1) {
129 		printk(KERN_ERR "qnx6:Requested file block number (%u) too big.",
130 				no);
131 		return 0;
132 	}
133 
134 	block = qnx6_get_devblock(s, ei->di_block_ptr[levelptr]);
135 
136 	for (i = 0; i < depth; i++) {
137 		bh = sb_bread(s, block);
138 		if (!bh) {
139 			printk(KERN_ERR "qnx6:Error reading block (%u)\n",
140 					block);
141 			return 0;
142 		}
143 		bitdelta -= ptrbits;
144 		levelptr = (no >> bitdelta) & mask;
145 		ptr = ((__fs32 *)bh->b_data)[levelptr];
146 
147 		if (!qnx6_check_blockptr(ptr))
148 			return 0;
149 
150 		block = qnx6_get_devblock(s, ptr);
151 		brelse(bh);
152 	}
153 	return block;
154 }
155 
156 static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf)
157 {
158 	struct super_block *sb = dentry->d_sb;
159 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
160 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
161 
162 	buf->f_type    = sb->s_magic;
163 	buf->f_bsize   = sb->s_blocksize;
164 	buf->f_blocks  = fs32_to_cpu(sbi, sbi->sb->sb_num_blocks);
165 	buf->f_bfree   = fs32_to_cpu(sbi, sbi->sb->sb_free_blocks);
166 	buf->f_files   = fs32_to_cpu(sbi, sbi->sb->sb_num_inodes);
167 	buf->f_ffree   = fs32_to_cpu(sbi, sbi->sb->sb_free_inodes);
168 	buf->f_bavail  = buf->f_bfree;
169 	buf->f_namelen = QNX6_LONG_NAME_MAX;
170 	buf->f_fsid.val[0] = (u32)id;
171 	buf->f_fsid.val[1] = (u32)(id >> 32);
172 
173 	return 0;
174 }
175 
176 /*
177  * Check the root directory of the filesystem to make sure
178  * it really _is_ a qnx6 filesystem, and to check the size
179  * of the directory entry.
180  */
181 static const char *qnx6_checkroot(struct super_block *s)
182 {
183 	static char match_root[2][3] = {".\0\0", "..\0"};
184 	int i, error = 0;
185 	struct qnx6_dir_entry *dir_entry;
186 	struct inode *root = s->s_root->d_inode;
187 	struct address_space *mapping = root->i_mapping;
188 	struct page *page = read_mapping_page(mapping, 0, NULL);
189 	if (IS_ERR(page))
190 		return "error reading root directory";
191 	kmap(page);
192 	dir_entry = page_address(page);
193 	for (i = 0; i < 2; i++) {
194 		/* maximum 3 bytes - due to match_root limitation */
195 		if (strncmp(dir_entry[i].de_fname, match_root[i], 3))
196 			error = 1;
197 	}
198 	qnx6_put_page(page);
199 	if (error)
200 		return "error reading root directory.";
201 	return NULL;
202 }
203 
204 #ifdef CONFIG_QNX6FS_DEBUG
205 void qnx6_superblock_debug(struct qnx6_super_block *sb, struct super_block *s)
206 {
207 	struct qnx6_sb_info *sbi = QNX6_SB(s);
208 
209 	QNX6DEBUG((KERN_INFO "magic: %08x\n",
210 				fs32_to_cpu(sbi, sb->sb_magic)));
211 	QNX6DEBUG((KERN_INFO "checksum: %08x\n",
212 				fs32_to_cpu(sbi, sb->sb_checksum)));
213 	QNX6DEBUG((KERN_INFO "serial: %llx\n",
214 				fs64_to_cpu(sbi, sb->sb_serial)));
215 	QNX6DEBUG((KERN_INFO "flags: %08x\n",
216 				fs32_to_cpu(sbi, sb->sb_flags)));
217 	QNX6DEBUG((KERN_INFO "blocksize: %08x\n",
218 				fs32_to_cpu(sbi, sb->sb_blocksize)));
219 	QNX6DEBUG((KERN_INFO "num_inodes: %08x\n",
220 				fs32_to_cpu(sbi, sb->sb_num_inodes)));
221 	QNX6DEBUG((KERN_INFO "free_inodes: %08x\n",
222 				fs32_to_cpu(sbi, sb->sb_free_inodes)));
223 	QNX6DEBUG((KERN_INFO "num_blocks: %08x\n",
224 				fs32_to_cpu(sbi, sb->sb_num_blocks)));
225 	QNX6DEBUG((KERN_INFO "free_blocks: %08x\n",
226 				fs32_to_cpu(sbi, sb->sb_free_blocks)));
227 	QNX6DEBUG((KERN_INFO "inode_levels: %02x\n",
228 				sb->Inode.levels));
229 }
230 #endif
231 
232 enum {
233 	Opt_mmifs,
234 	Opt_err
235 };
236 
237 static const match_table_t tokens = {
238 	{Opt_mmifs, "mmi_fs"},
239 	{Opt_err, NULL}
240 };
241 
242 static int qnx6_parse_options(char *options, struct super_block *sb)
243 {
244 	char *p;
245 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
246 	substring_t args[MAX_OPT_ARGS];
247 
248 	if (!options)
249 		return 1;
250 
251 	while ((p = strsep(&options, ",")) != NULL) {
252 		int token;
253 		if (!*p)
254 			continue;
255 
256 		token = match_token(p, tokens, args);
257 		switch (token) {
258 		case Opt_mmifs:
259 			set_opt(sbi->s_mount_opt, MMI_FS);
260 			break;
261 		default:
262 			return 0;
263 		}
264 	}
265 	return 1;
266 }
267 
268 static struct buffer_head *qnx6_check_first_superblock(struct super_block *s,
269 				int offset, int silent)
270 {
271 	struct qnx6_sb_info *sbi = QNX6_SB(s);
272 	struct buffer_head *bh;
273 	struct qnx6_super_block *sb;
274 
275 	/* Check the superblock signatures
276 	   start with the first superblock */
277 	bh = sb_bread(s, offset);
278 	if (!bh) {
279 		printk(KERN_ERR "qnx6: unable to read the first superblock\n");
280 		return NULL;
281 	}
282 	sb = (struct qnx6_super_block *)bh->b_data;
283 	if (fs32_to_cpu(sbi, sb->sb_magic) != QNX6_SUPER_MAGIC) {
284 		sbi->s_bytesex = BYTESEX_BE;
285 		if (fs32_to_cpu(sbi, sb->sb_magic) == QNX6_SUPER_MAGIC) {
286 			/* we got a big endian fs */
287 			QNX6DEBUG((KERN_INFO "qnx6: fs got different"
288 					" endianness.\n"));
289 			return bh;
290 		} else
291 			sbi->s_bytesex = BYTESEX_LE;
292 		if (!silent) {
293 			if (offset == 0) {
294 				printk(KERN_ERR "qnx6: wrong signature (magic)"
295 					" in superblock #1.\n");
296 			} else {
297 				printk(KERN_INFO "qnx6: wrong signature (magic)"
298 					" at position (0x%lx) - will try"
299 					" alternative position (0x0000).\n",
300 						offset * s->s_blocksize);
301 			}
302 		}
303 		brelse(bh);
304 		return NULL;
305 	}
306 	return bh;
307 }
308 
309 static struct inode *qnx6_private_inode(struct super_block *s,
310 					struct qnx6_root_node *p);
311 
312 static int qnx6_fill_super(struct super_block *s, void *data, int silent)
313 {
314 	struct buffer_head *bh1 = NULL, *bh2 = NULL;
315 	struct qnx6_super_block *sb1 = NULL, *sb2 = NULL;
316 	struct qnx6_sb_info *sbi;
317 	struct inode *root;
318 	const char *errmsg;
319 	struct qnx6_sb_info *qs;
320 	int ret = -EINVAL;
321 	u64 offset;
322 	int bootblock_offset = QNX6_BOOTBLOCK_SIZE;
323 
324 	qs = kzalloc(sizeof(struct qnx6_sb_info), GFP_KERNEL);
325 	if (!qs)
326 		return -ENOMEM;
327 	s->s_fs_info = qs;
328 
329 	/* Superblock always is 512 Byte long */
330 	if (!sb_set_blocksize(s, QNX6_SUPERBLOCK_SIZE)) {
331 		printk(KERN_ERR "qnx6: unable to set blocksize\n");
332 		goto outnobh;
333 	}
334 
335 	/* parse the mount-options */
336 	if (!qnx6_parse_options((char *) data, s)) {
337 		printk(KERN_ERR "qnx6: invalid mount options.\n");
338 		goto outnobh;
339 	}
340 	if (test_opt(s, MMI_FS)) {
341 		sb1 = qnx6_mmi_fill_super(s, silent);
342 		if (sb1)
343 			goto mmi_success;
344 		else
345 			goto outnobh;
346 	}
347 	sbi = QNX6_SB(s);
348 	sbi->s_bytesex = BYTESEX_LE;
349 	/* Check the superblock signatures
350 	   start with the first superblock */
351 	bh1 = qnx6_check_first_superblock(s,
352 		bootblock_offset / QNX6_SUPERBLOCK_SIZE, silent);
353 	if (!bh1) {
354 		/* try again without bootblock offset */
355 		bh1 = qnx6_check_first_superblock(s, 0, silent);
356 		if (!bh1) {
357 			printk(KERN_ERR "qnx6: unable to read the first superblock\n");
358 			goto outnobh;
359 		}
360 		/* seems that no bootblock at partition start */
361 		bootblock_offset = 0;
362 	}
363 	sb1 = (struct qnx6_super_block *)bh1->b_data;
364 
365 #ifdef CONFIG_QNX6FS_DEBUG
366 	qnx6_superblock_debug(sb1, s);
367 #endif
368 
369 	/* checksum check - start at byte 8 and end at byte 512 */
370 	if (fs32_to_cpu(sbi, sb1->sb_checksum) !=
371 			crc32_be(0, (char *)(bh1->b_data + 8), 504)) {
372 		printk(KERN_ERR "qnx6: superblock #1 checksum error\n");
373 		goto out;
374 	}
375 
376 	/* set new blocksize */
377 	if (!sb_set_blocksize(s, fs32_to_cpu(sbi, sb1->sb_blocksize))) {
378 		printk(KERN_ERR "qnx6: unable to set blocksize\n");
379 		goto out;
380 	}
381 	/* blocksize invalidates bh - pull it back in */
382 	brelse(bh1);
383 	bh1 = sb_bread(s, bootblock_offset >> s->s_blocksize_bits);
384 	if (!bh1)
385 		goto outnobh;
386 	sb1 = (struct qnx6_super_block *)bh1->b_data;
387 
388 	/* calculate second superblock blocknumber */
389 	offset = fs32_to_cpu(sbi, sb1->sb_num_blocks) +
390 		(bootblock_offset >> s->s_blocksize_bits) +
391 		(QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits);
392 
393 	/* set bootblock offset */
394 	sbi->s_blks_off = (bootblock_offset >> s->s_blocksize_bits) +
395 			  (QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits);
396 
397 	/* next the second superblock */
398 	bh2 = sb_bread(s, offset);
399 	if (!bh2) {
400 		printk(KERN_ERR "qnx6: unable to read the second superblock\n");
401 		goto out;
402 	}
403 	sb2 = (struct qnx6_super_block *)bh2->b_data;
404 	if (fs32_to_cpu(sbi, sb2->sb_magic) != QNX6_SUPER_MAGIC) {
405 		if (!silent)
406 			printk(KERN_ERR "qnx6: wrong signature (magic)"
407 					" in superblock #2.\n");
408 		goto out;
409 	}
410 
411 	/* checksum check - start at byte 8 and end at byte 512 */
412 	if (fs32_to_cpu(sbi, sb2->sb_checksum) !=
413 				crc32_be(0, (char *)(bh2->b_data + 8), 504)) {
414 		printk(KERN_ERR "qnx6: superblock #2 checksum error\n");
415 		goto out;
416 	}
417 
418 	if (fs64_to_cpu(sbi, sb1->sb_serial) >=
419 					fs64_to_cpu(sbi, sb2->sb_serial)) {
420 		/* superblock #1 active */
421 		sbi->sb_buf = bh1;
422 		sbi->sb = (struct qnx6_super_block *)bh1->b_data;
423 		brelse(bh2);
424 		printk(KERN_INFO "qnx6: superblock #1 active\n");
425 	} else {
426 		/* superblock #2 active */
427 		sbi->sb_buf = bh2;
428 		sbi->sb = (struct qnx6_super_block *)bh2->b_data;
429 		brelse(bh1);
430 		printk(KERN_INFO "qnx6: superblock #2 active\n");
431 	}
432 mmi_success:
433 	/* sanity check - limit maximum indirect pointer levels */
434 	if (sb1->Inode.levels > QNX6_PTR_MAX_LEVELS) {
435 		printk(KERN_ERR "qnx6: too many inode levels (max %i, sb %i)\n",
436 			QNX6_PTR_MAX_LEVELS, sb1->Inode.levels);
437 		goto out;
438 	}
439 	if (sb1->Longfile.levels > QNX6_PTR_MAX_LEVELS) {
440 		printk(KERN_ERR "qnx6: too many longfilename levels"
441 				" (max %i, sb %i)\n",
442 			QNX6_PTR_MAX_LEVELS, sb1->Longfile.levels);
443 		goto out;
444 	}
445 	s->s_op = &qnx6_sops;
446 	s->s_magic = QNX6_SUPER_MAGIC;
447 	s->s_flags |= MS_RDONLY;        /* Yup, read-only yet */
448 
449 	/* ease the later tree level calculations */
450 	sbi = QNX6_SB(s);
451 	sbi->s_ptrbits = ilog2(s->s_blocksize / 4);
452 	sbi->inodes = qnx6_private_inode(s, &sb1->Inode);
453 	if (!sbi->inodes)
454 		goto out;
455 	sbi->longfile = qnx6_private_inode(s, &sb1->Longfile);
456 	if (!sbi->longfile)
457 		goto out1;
458 
459 	/* prefetch root inode */
460 	root = qnx6_iget(s, QNX6_ROOT_INO);
461 	if (IS_ERR(root)) {
462 		printk(KERN_ERR "qnx6: get inode failed\n");
463 		ret = PTR_ERR(root);
464 		goto out2;
465 	}
466 
467 	ret = -ENOMEM;
468 	s->s_root = d_make_root(root);
469 	if (!s->s_root)
470 		goto out2;
471 
472 	ret = -EINVAL;
473 	errmsg = qnx6_checkroot(s);
474 	if (errmsg != NULL) {
475 		if (!silent)
476 			printk(KERN_ERR "qnx6: %s\n", errmsg);
477 		goto out3;
478 	}
479 	return 0;
480 
481 out3:
482 	dput(s->s_root);
483 	s->s_root = NULL;
484 out2:
485 	iput(sbi->longfile);
486 out1:
487 	iput(sbi->inodes);
488 out:
489 	if (bh1)
490 		brelse(bh1);
491 	if (bh2)
492 		brelse(bh2);
493 outnobh:
494 	kfree(qs);
495 	s->s_fs_info = NULL;
496 	return ret;
497 }
498 
499 static void qnx6_put_super(struct super_block *sb)
500 {
501 	struct qnx6_sb_info *qs = QNX6_SB(sb);
502 	brelse(qs->sb_buf);
503 	iput(qs->longfile);
504 	iput(qs->inodes);
505 	kfree(qs);
506 	sb->s_fs_info = NULL;
507 	return;
508 }
509 
510 static sector_t qnx6_bmap(struct address_space *mapping, sector_t block)
511 {
512 	return generic_block_bmap(mapping, block, qnx6_get_block);
513 }
514 static const struct address_space_operations qnx6_aops = {
515 	.readpage	= qnx6_readpage,
516 	.readpages	= qnx6_readpages,
517 	.bmap		= qnx6_bmap
518 };
519 
520 static struct inode *qnx6_private_inode(struct super_block *s,
521 					struct qnx6_root_node *p)
522 {
523 	struct inode *inode = new_inode(s);
524 	if (inode) {
525 		struct qnx6_inode_info *ei = QNX6_I(inode);
526 		struct qnx6_sb_info *sbi = QNX6_SB(s);
527 		inode->i_size = fs64_to_cpu(sbi, p->size);
528 		memcpy(ei->di_block_ptr, p->ptr, sizeof(p->ptr));
529 		ei->di_filelevels = p->levels;
530 		inode->i_mode = S_IFREG | S_IRUSR; /* probably wrong */
531 		inode->i_mapping->a_ops = &qnx6_aops;
532 	}
533 	return inode;
534 }
535 
536 struct inode *qnx6_iget(struct super_block *sb, unsigned ino)
537 {
538 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
539 	struct qnx6_inode_entry *raw_inode;
540 	struct inode *inode;
541 	struct qnx6_inode_info	*ei;
542 	struct address_space *mapping;
543 	struct page *page;
544 	u32 n, offs;
545 
546 	inode = iget_locked(sb, ino);
547 	if (!inode)
548 		return ERR_PTR(-ENOMEM);
549 	if (!(inode->i_state & I_NEW))
550 		return inode;
551 
552 	ei = QNX6_I(inode);
553 
554 	inode->i_mode = 0;
555 
556 	if (ino == 0) {
557 		printk(KERN_ERR "qnx6: bad inode number on dev %s: %u is "
558 				"out of range\n",
559 		       sb->s_id, ino);
560 		iget_failed(inode);
561 		return ERR_PTR(-EIO);
562 	}
563 	n = (ino - 1) >> (PAGE_CACHE_SHIFT - QNX6_INODE_SIZE_BITS);
564 	offs = (ino - 1) & (~PAGE_CACHE_MASK >> QNX6_INODE_SIZE_BITS);
565 	mapping = sbi->inodes->i_mapping;
566 	page = read_mapping_page(mapping, n, NULL);
567 	if (IS_ERR(page)) {
568 		printk(KERN_ERR "qnx6: major problem: unable to read inode from "
569 		       "dev %s\n", sb->s_id);
570 		iget_failed(inode);
571 		return ERR_CAST(page);
572 	}
573 	kmap(page);
574 	raw_inode = ((struct qnx6_inode_entry *)page_address(page)) + offs;
575 
576 	inode->i_mode    = fs16_to_cpu(sbi, raw_inode->di_mode);
577 	i_uid_write(inode, (uid_t)fs32_to_cpu(sbi, raw_inode->di_uid));
578 	i_gid_write(inode, (gid_t)fs32_to_cpu(sbi, raw_inode->di_gid));
579 	inode->i_size    = fs64_to_cpu(sbi, raw_inode->di_size);
580 	inode->i_mtime.tv_sec   = fs32_to_cpu(sbi, raw_inode->di_mtime);
581 	inode->i_mtime.tv_nsec = 0;
582 	inode->i_atime.tv_sec   = fs32_to_cpu(sbi, raw_inode->di_atime);
583 	inode->i_atime.tv_nsec = 0;
584 	inode->i_ctime.tv_sec   = fs32_to_cpu(sbi, raw_inode->di_ctime);
585 	inode->i_ctime.tv_nsec = 0;
586 
587 	/* calc blocks based on 512 byte blocksize */
588 	inode->i_blocks = (inode->i_size + 511) >> 9;
589 
590 	memcpy(&ei->di_block_ptr, &raw_inode->di_block_ptr,
591 				sizeof(raw_inode->di_block_ptr));
592 	ei->di_filelevels = raw_inode->di_filelevels;
593 
594 	if (S_ISREG(inode->i_mode)) {
595 		inode->i_fop = &generic_ro_fops;
596 		inode->i_mapping->a_ops = &qnx6_aops;
597 	} else if (S_ISDIR(inode->i_mode)) {
598 		inode->i_op = &qnx6_dir_inode_operations;
599 		inode->i_fop = &qnx6_dir_operations;
600 		inode->i_mapping->a_ops = &qnx6_aops;
601 	} else if (S_ISLNK(inode->i_mode)) {
602 		inode->i_op = &page_symlink_inode_operations;
603 		inode->i_mapping->a_ops = &qnx6_aops;
604 	} else
605 		init_special_inode(inode, inode->i_mode, 0);
606 	qnx6_put_page(page);
607 	unlock_new_inode(inode);
608 	return inode;
609 }
610 
611 static struct kmem_cache *qnx6_inode_cachep;
612 
613 static struct inode *qnx6_alloc_inode(struct super_block *sb)
614 {
615 	struct qnx6_inode_info *ei;
616 	ei = kmem_cache_alloc(qnx6_inode_cachep, GFP_KERNEL);
617 	if (!ei)
618 		return NULL;
619 	return &ei->vfs_inode;
620 }
621 
622 static void qnx6_i_callback(struct rcu_head *head)
623 {
624 	struct inode *inode = container_of(head, struct inode, i_rcu);
625 	kmem_cache_free(qnx6_inode_cachep, QNX6_I(inode));
626 }
627 
628 static void qnx6_destroy_inode(struct inode *inode)
629 {
630 	call_rcu(&inode->i_rcu, qnx6_i_callback);
631 }
632 
633 static void init_once(void *foo)
634 {
635 	struct qnx6_inode_info *ei = (struct qnx6_inode_info *) foo;
636 
637 	inode_init_once(&ei->vfs_inode);
638 }
639 
640 static int init_inodecache(void)
641 {
642 	qnx6_inode_cachep = kmem_cache_create("qnx6_inode_cache",
643 					     sizeof(struct qnx6_inode_info),
644 					     0, (SLAB_RECLAIM_ACCOUNT|
645 						SLAB_MEM_SPREAD),
646 					     init_once);
647 	if (!qnx6_inode_cachep)
648 		return -ENOMEM;
649 	return 0;
650 }
651 
652 static void destroy_inodecache(void)
653 {
654 	/*
655 	 * Make sure all delayed rcu free inodes are flushed before we
656 	 * destroy cache.
657 	 */
658 	rcu_barrier();
659 	kmem_cache_destroy(qnx6_inode_cachep);
660 }
661 
662 static struct dentry *qnx6_mount(struct file_system_type *fs_type,
663 	int flags, const char *dev_name, void *data)
664 {
665 	return mount_bdev(fs_type, flags, dev_name, data, qnx6_fill_super);
666 }
667 
668 static struct file_system_type qnx6_fs_type = {
669 	.owner		= THIS_MODULE,
670 	.name		= "qnx6",
671 	.mount		= qnx6_mount,
672 	.kill_sb	= kill_block_super,
673 	.fs_flags	= FS_REQUIRES_DEV,
674 };
675 MODULE_ALIAS_FS("qnx6");
676 
677 static int __init init_qnx6_fs(void)
678 {
679 	int err;
680 
681 	err = init_inodecache();
682 	if (err)
683 		return err;
684 
685 	err = register_filesystem(&qnx6_fs_type);
686 	if (err) {
687 		destroy_inodecache();
688 		return err;
689 	}
690 
691 	printk(KERN_INFO "QNX6 filesystem 1.0.0 registered.\n");
692 	return 0;
693 }
694 
695 static void __exit exit_qnx6_fs(void)
696 {
697 	unregister_filesystem(&qnx6_fs_type);
698 	destroy_inodecache();
699 }
700 
701 module_init(init_qnx6_fs)
702 module_exit(exit_qnx6_fs)
703 MODULE_LICENSE("GPL");
704