xref: /openbmc/linux/fs/qnx6/inode.c (revision 95298d63)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * QNX6 file system, Linux implementation.
4  *
5  * Version : 1.0.0
6  *
7  * History :
8  *
9  * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
10  * 16-02-2012 pagemap extension by Al Viro
11  *
12  */
13 
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/highuid.h>
18 #include <linux/pagemap.h>
19 #include <linux/buffer_head.h>
20 #include <linux/writeback.h>
21 #include <linux/statfs.h>
22 #include <linux/parser.h>
23 #include <linux/seq_file.h>
24 #include <linux/mount.h>
25 #include <linux/crc32.h>
26 #include <linux/mpage.h>
27 #include "qnx6.h"
28 
29 static const struct super_operations qnx6_sops;
30 
31 static void qnx6_put_super(struct super_block *sb);
32 static struct inode *qnx6_alloc_inode(struct super_block *sb);
33 static void qnx6_free_inode(struct inode *inode);
34 static int qnx6_remount(struct super_block *sb, int *flags, char *data);
35 static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf);
36 static int qnx6_show_options(struct seq_file *seq, struct dentry *root);
37 
38 static const struct super_operations qnx6_sops = {
39 	.alloc_inode	= qnx6_alloc_inode,
40 	.free_inode	= qnx6_free_inode,
41 	.put_super	= qnx6_put_super,
42 	.statfs		= qnx6_statfs,
43 	.remount_fs	= qnx6_remount,
44 	.show_options	= qnx6_show_options,
45 };
46 
47 static int qnx6_show_options(struct seq_file *seq, struct dentry *root)
48 {
49 	struct super_block *sb = root->d_sb;
50 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
51 
52 	if (sbi->s_mount_opt & QNX6_MOUNT_MMI_FS)
53 		seq_puts(seq, ",mmi_fs");
54 	return 0;
55 }
56 
57 static int qnx6_remount(struct super_block *sb, int *flags, char *data)
58 {
59 	sync_filesystem(sb);
60 	*flags |= SB_RDONLY;
61 	return 0;
62 }
63 
64 static unsigned qnx6_get_devblock(struct super_block *sb, __fs32 block)
65 {
66 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
67 	return fs32_to_cpu(sbi, block) + sbi->s_blks_off;
68 }
69 
70 static unsigned qnx6_block_map(struct inode *inode, unsigned iblock);
71 
72 static int qnx6_get_block(struct inode *inode, sector_t iblock,
73 			struct buffer_head *bh, int create)
74 {
75 	unsigned phys;
76 
77 	pr_debug("qnx6_get_block inode=[%ld] iblock=[%ld]\n",
78 		 inode->i_ino, (unsigned long)iblock);
79 
80 	phys = qnx6_block_map(inode, iblock);
81 	if (phys) {
82 		/* logical block is before EOF */
83 		map_bh(bh, inode->i_sb, phys);
84 	}
85 	return 0;
86 }
87 
88 static int qnx6_check_blockptr(__fs32 ptr)
89 {
90 	if (ptr == ~(__fs32)0) {
91 		pr_err("hit unused blockpointer.\n");
92 		return 0;
93 	}
94 	return 1;
95 }
96 
97 static int qnx6_readpage(struct file *file, struct page *page)
98 {
99 	return mpage_readpage(page, qnx6_get_block);
100 }
101 
102 static void qnx6_readahead(struct readahead_control *rac)
103 {
104 	mpage_readahead(rac, qnx6_get_block);
105 }
106 
107 /*
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
110  */
111 static unsigned qnx6_block_map(struct inode *inode, unsigned no)
112 {
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);
116 	unsigned block = 0;
117 	struct buffer_head *bh;
118 	__fs32 ptr;
119 	int levelptr;
120 	int ptrbits = sbi->s_ptrbits;
121 	int bitdelta;
122 	u32 mask = (1 << ptrbits) - 1;
123 	int depth = ei->di_filelevels;
124 	int i;
125 
126 	bitdelta = ptrbits * depth;
127 	levelptr = no >> bitdelta;
128 
129 	if (levelptr > QNX6_NO_DIRECT_POINTERS - 1) {
130 		pr_err("Requested file block number (%u) too big.", 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 			pr_err("Error reading block (%u)\n", block);
140 			return 0;
141 		}
142 		bitdelta -= ptrbits;
143 		levelptr = (no >> bitdelta) & mask;
144 		ptr = ((__fs32 *)bh->b_data)[levelptr];
145 
146 		if (!qnx6_check_blockptr(ptr))
147 			return 0;
148 
149 		block = qnx6_get_devblock(s, ptr);
150 		brelse(bh);
151 	}
152 	return block;
153 }
154 
155 static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf)
156 {
157 	struct super_block *sb = dentry->d_sb;
158 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
159 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
160 
161 	buf->f_type    = sb->s_magic;
162 	buf->f_bsize   = sb->s_blocksize;
163 	buf->f_blocks  = fs32_to_cpu(sbi, sbi->sb->sb_num_blocks);
164 	buf->f_bfree   = fs32_to_cpu(sbi, sbi->sb->sb_free_blocks);
165 	buf->f_files   = fs32_to_cpu(sbi, sbi->sb->sb_num_inodes);
166 	buf->f_ffree   = fs32_to_cpu(sbi, sbi->sb->sb_free_inodes);
167 	buf->f_bavail  = buf->f_bfree;
168 	buf->f_namelen = QNX6_LONG_NAME_MAX;
169 	buf->f_fsid.val[0] = (u32)id;
170 	buf->f_fsid.val[1] = (u32)(id >> 32);
171 
172 	return 0;
173 }
174 
175 /*
176  * Check the root directory of the filesystem to make sure
177  * it really _is_ a qnx6 filesystem, and to check the size
178  * of the directory entry.
179  */
180 static const char *qnx6_checkroot(struct super_block *s)
181 {
182 	static char match_root[2][3] = {".\0\0", "..\0"};
183 	int i, error = 0;
184 	struct qnx6_dir_entry *dir_entry;
185 	struct inode *root = d_inode(s->s_root);
186 	struct address_space *mapping = root->i_mapping;
187 	struct page *page = read_mapping_page(mapping, 0, NULL);
188 	if (IS_ERR(page))
189 		return "error reading root directory";
190 	kmap(page);
191 	dir_entry = page_address(page);
192 	for (i = 0; i < 2; i++) {
193 		/* maximum 3 bytes - due to match_root limitation */
194 		if (strncmp(dir_entry[i].de_fname, match_root[i], 3))
195 			error = 1;
196 	}
197 	qnx6_put_page(page);
198 	if (error)
199 		return "error reading root directory.";
200 	return NULL;
201 }
202 
203 #ifdef CONFIG_QNX6FS_DEBUG
204 void qnx6_superblock_debug(struct qnx6_super_block *sb, struct super_block *s)
205 {
206 	struct qnx6_sb_info *sbi = QNX6_SB(s);
207 
208 	pr_debug("magic: %08x\n", fs32_to_cpu(sbi, sb->sb_magic));
209 	pr_debug("checksum: %08x\n", fs32_to_cpu(sbi, sb->sb_checksum));
210 	pr_debug("serial: %llx\n", fs64_to_cpu(sbi, sb->sb_serial));
211 	pr_debug("flags: %08x\n", fs32_to_cpu(sbi, sb->sb_flags));
212 	pr_debug("blocksize: %08x\n", fs32_to_cpu(sbi, sb->sb_blocksize));
213 	pr_debug("num_inodes: %08x\n", fs32_to_cpu(sbi, sb->sb_num_inodes));
214 	pr_debug("free_inodes: %08x\n", fs32_to_cpu(sbi, sb->sb_free_inodes));
215 	pr_debug("num_blocks: %08x\n", fs32_to_cpu(sbi, sb->sb_num_blocks));
216 	pr_debug("free_blocks: %08x\n", fs32_to_cpu(sbi, sb->sb_free_blocks));
217 	pr_debug("inode_levels: %02x\n", sb->Inode.levels);
218 }
219 #endif
220 
221 enum {
222 	Opt_mmifs,
223 	Opt_err
224 };
225 
226 static const match_table_t tokens = {
227 	{Opt_mmifs, "mmi_fs"},
228 	{Opt_err, NULL}
229 };
230 
231 static int qnx6_parse_options(char *options, struct super_block *sb)
232 {
233 	char *p;
234 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
235 	substring_t args[MAX_OPT_ARGS];
236 
237 	if (!options)
238 		return 1;
239 
240 	while ((p = strsep(&options, ",")) != NULL) {
241 		int token;
242 		if (!*p)
243 			continue;
244 
245 		token = match_token(p, tokens, args);
246 		switch (token) {
247 		case Opt_mmifs:
248 			set_opt(sbi->s_mount_opt, MMI_FS);
249 			break;
250 		default:
251 			return 0;
252 		}
253 	}
254 	return 1;
255 }
256 
257 static struct buffer_head *qnx6_check_first_superblock(struct super_block *s,
258 				int offset, int silent)
259 {
260 	struct qnx6_sb_info *sbi = QNX6_SB(s);
261 	struct buffer_head *bh;
262 	struct qnx6_super_block *sb;
263 
264 	/* Check the superblock signatures
265 	   start with the first superblock */
266 	bh = sb_bread(s, offset);
267 	if (!bh) {
268 		pr_err("unable to read the first superblock\n");
269 		return NULL;
270 	}
271 	sb = (struct qnx6_super_block *)bh->b_data;
272 	if (fs32_to_cpu(sbi, sb->sb_magic) != QNX6_SUPER_MAGIC) {
273 		sbi->s_bytesex = BYTESEX_BE;
274 		if (fs32_to_cpu(sbi, sb->sb_magic) == QNX6_SUPER_MAGIC) {
275 			/* we got a big endian fs */
276 			pr_debug("fs got different endianness.\n");
277 			return bh;
278 		} else
279 			sbi->s_bytesex = BYTESEX_LE;
280 		if (!silent) {
281 			if (offset == 0) {
282 				pr_err("wrong signature (magic) in superblock #1.\n");
283 			} else {
284 				pr_info("wrong signature (magic) at position (0x%lx) - will try alternative position (0x0000).\n",
285 					offset * s->s_blocksize);
286 			}
287 		}
288 		brelse(bh);
289 		return NULL;
290 	}
291 	return bh;
292 }
293 
294 static struct inode *qnx6_private_inode(struct super_block *s,
295 					struct qnx6_root_node *p);
296 
297 static int qnx6_fill_super(struct super_block *s, void *data, int silent)
298 {
299 	struct buffer_head *bh1 = NULL, *bh2 = NULL;
300 	struct qnx6_super_block *sb1 = NULL, *sb2 = NULL;
301 	struct qnx6_sb_info *sbi;
302 	struct inode *root;
303 	const char *errmsg;
304 	struct qnx6_sb_info *qs;
305 	int ret = -EINVAL;
306 	u64 offset;
307 	int bootblock_offset = QNX6_BOOTBLOCK_SIZE;
308 
309 	qs = kzalloc(sizeof(struct qnx6_sb_info), GFP_KERNEL);
310 	if (!qs)
311 		return -ENOMEM;
312 	s->s_fs_info = qs;
313 
314 	/* Superblock always is 512 Byte long */
315 	if (!sb_set_blocksize(s, QNX6_SUPERBLOCK_SIZE)) {
316 		pr_err("unable to set blocksize\n");
317 		goto outnobh;
318 	}
319 
320 	/* parse the mount-options */
321 	if (!qnx6_parse_options((char *) data, s)) {
322 		pr_err("invalid mount options.\n");
323 		goto outnobh;
324 	}
325 	if (test_opt(s, MMI_FS)) {
326 		sb1 = qnx6_mmi_fill_super(s, silent);
327 		if (sb1)
328 			goto mmi_success;
329 		else
330 			goto outnobh;
331 	}
332 	sbi = QNX6_SB(s);
333 	sbi->s_bytesex = BYTESEX_LE;
334 	/* Check the superblock signatures
335 	   start with the first superblock */
336 	bh1 = qnx6_check_first_superblock(s,
337 		bootblock_offset / QNX6_SUPERBLOCK_SIZE, silent);
338 	if (!bh1) {
339 		/* try again without bootblock offset */
340 		bh1 = qnx6_check_first_superblock(s, 0, silent);
341 		if (!bh1) {
342 			pr_err("unable to read the first superblock\n");
343 			goto outnobh;
344 		}
345 		/* seems that no bootblock at partition start */
346 		bootblock_offset = 0;
347 	}
348 	sb1 = (struct qnx6_super_block *)bh1->b_data;
349 
350 #ifdef CONFIG_QNX6FS_DEBUG
351 	qnx6_superblock_debug(sb1, s);
352 #endif
353 
354 	/* checksum check - start at byte 8 and end at byte 512 */
355 	if (fs32_to_cpu(sbi, sb1->sb_checksum) !=
356 			crc32_be(0, (char *)(bh1->b_data + 8), 504)) {
357 		pr_err("superblock #1 checksum error\n");
358 		goto out;
359 	}
360 
361 	/* set new blocksize */
362 	if (!sb_set_blocksize(s, fs32_to_cpu(sbi, sb1->sb_blocksize))) {
363 		pr_err("unable to set blocksize\n");
364 		goto out;
365 	}
366 	/* blocksize invalidates bh - pull it back in */
367 	brelse(bh1);
368 	bh1 = sb_bread(s, bootblock_offset >> s->s_blocksize_bits);
369 	if (!bh1)
370 		goto outnobh;
371 	sb1 = (struct qnx6_super_block *)bh1->b_data;
372 
373 	/* calculate second superblock blocknumber */
374 	offset = fs32_to_cpu(sbi, sb1->sb_num_blocks) +
375 		(bootblock_offset >> s->s_blocksize_bits) +
376 		(QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits);
377 
378 	/* set bootblock offset */
379 	sbi->s_blks_off = (bootblock_offset >> s->s_blocksize_bits) +
380 			  (QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits);
381 
382 	/* next the second superblock */
383 	bh2 = sb_bread(s, offset);
384 	if (!bh2) {
385 		pr_err("unable to read the second superblock\n");
386 		goto out;
387 	}
388 	sb2 = (struct qnx6_super_block *)bh2->b_data;
389 	if (fs32_to_cpu(sbi, sb2->sb_magic) != QNX6_SUPER_MAGIC) {
390 		if (!silent)
391 			pr_err("wrong signature (magic) in superblock #2.\n");
392 		goto out;
393 	}
394 
395 	/* checksum check - start at byte 8 and end at byte 512 */
396 	if (fs32_to_cpu(sbi, sb2->sb_checksum) !=
397 				crc32_be(0, (char *)(bh2->b_data + 8), 504)) {
398 		pr_err("superblock #2 checksum error\n");
399 		goto out;
400 	}
401 
402 	if (fs64_to_cpu(sbi, sb1->sb_serial) >=
403 					fs64_to_cpu(sbi, sb2->sb_serial)) {
404 		/* superblock #1 active */
405 		sbi->sb_buf = bh1;
406 		sbi->sb = (struct qnx6_super_block *)bh1->b_data;
407 		brelse(bh2);
408 		pr_info("superblock #1 active\n");
409 	} else {
410 		/* superblock #2 active */
411 		sbi->sb_buf = bh2;
412 		sbi->sb = (struct qnx6_super_block *)bh2->b_data;
413 		brelse(bh1);
414 		pr_info("superblock #2 active\n");
415 	}
416 mmi_success:
417 	/* sanity check - limit maximum indirect pointer levels */
418 	if (sb1->Inode.levels > QNX6_PTR_MAX_LEVELS) {
419 		pr_err("too many inode levels (max %i, sb %i)\n",
420 		       QNX6_PTR_MAX_LEVELS, sb1->Inode.levels);
421 		goto out;
422 	}
423 	if (sb1->Longfile.levels > QNX6_PTR_MAX_LEVELS) {
424 		pr_err("too many longfilename levels (max %i, sb %i)\n",
425 		       QNX6_PTR_MAX_LEVELS, sb1->Longfile.levels);
426 		goto out;
427 	}
428 	s->s_op = &qnx6_sops;
429 	s->s_magic = QNX6_SUPER_MAGIC;
430 	s->s_flags |= SB_RDONLY;        /* Yup, read-only yet */
431 	s->s_time_min = 0;
432 	s->s_time_max = U32_MAX;
433 
434 	/* ease the later tree level calculations */
435 	sbi = QNX6_SB(s);
436 	sbi->s_ptrbits = ilog2(s->s_blocksize / 4);
437 	sbi->inodes = qnx6_private_inode(s, &sb1->Inode);
438 	if (!sbi->inodes)
439 		goto out;
440 	sbi->longfile = qnx6_private_inode(s, &sb1->Longfile);
441 	if (!sbi->longfile)
442 		goto out1;
443 
444 	/* prefetch root inode */
445 	root = qnx6_iget(s, QNX6_ROOT_INO);
446 	if (IS_ERR(root)) {
447 		pr_err("get inode failed\n");
448 		ret = PTR_ERR(root);
449 		goto out2;
450 	}
451 
452 	ret = -ENOMEM;
453 	s->s_root = d_make_root(root);
454 	if (!s->s_root)
455 		goto out2;
456 
457 	ret = -EINVAL;
458 	errmsg = qnx6_checkroot(s);
459 	if (errmsg != NULL) {
460 		if (!silent)
461 			pr_err("%s\n", errmsg);
462 		goto out3;
463 	}
464 	return 0;
465 
466 out3:
467 	dput(s->s_root);
468 	s->s_root = NULL;
469 out2:
470 	iput(sbi->longfile);
471 out1:
472 	iput(sbi->inodes);
473 out:
474 	if (bh1)
475 		brelse(bh1);
476 	if (bh2)
477 		brelse(bh2);
478 outnobh:
479 	kfree(qs);
480 	s->s_fs_info = NULL;
481 	return ret;
482 }
483 
484 static void qnx6_put_super(struct super_block *sb)
485 {
486 	struct qnx6_sb_info *qs = QNX6_SB(sb);
487 	brelse(qs->sb_buf);
488 	iput(qs->longfile);
489 	iput(qs->inodes);
490 	kfree(qs);
491 	sb->s_fs_info = NULL;
492 	return;
493 }
494 
495 static sector_t qnx6_bmap(struct address_space *mapping, sector_t block)
496 {
497 	return generic_block_bmap(mapping, block, qnx6_get_block);
498 }
499 static const struct address_space_operations qnx6_aops = {
500 	.readpage	= qnx6_readpage,
501 	.readahead	= qnx6_readahead,
502 	.bmap		= qnx6_bmap
503 };
504 
505 static struct inode *qnx6_private_inode(struct super_block *s,
506 					struct qnx6_root_node *p)
507 {
508 	struct inode *inode = new_inode(s);
509 	if (inode) {
510 		struct qnx6_inode_info *ei = QNX6_I(inode);
511 		struct qnx6_sb_info *sbi = QNX6_SB(s);
512 		inode->i_size = fs64_to_cpu(sbi, p->size);
513 		memcpy(ei->di_block_ptr, p->ptr, sizeof(p->ptr));
514 		ei->di_filelevels = p->levels;
515 		inode->i_mode = S_IFREG | S_IRUSR; /* probably wrong */
516 		inode->i_mapping->a_ops = &qnx6_aops;
517 	}
518 	return inode;
519 }
520 
521 struct inode *qnx6_iget(struct super_block *sb, unsigned ino)
522 {
523 	struct qnx6_sb_info *sbi = QNX6_SB(sb);
524 	struct qnx6_inode_entry *raw_inode;
525 	struct inode *inode;
526 	struct qnx6_inode_info	*ei;
527 	struct address_space *mapping;
528 	struct page *page;
529 	u32 n, offs;
530 
531 	inode = iget_locked(sb, ino);
532 	if (!inode)
533 		return ERR_PTR(-ENOMEM);
534 	if (!(inode->i_state & I_NEW))
535 		return inode;
536 
537 	ei = QNX6_I(inode);
538 
539 	inode->i_mode = 0;
540 
541 	if (ino == 0) {
542 		pr_err("bad inode number on dev %s: %u is out of range\n",
543 		       sb->s_id, ino);
544 		iget_failed(inode);
545 		return ERR_PTR(-EIO);
546 	}
547 	n = (ino - 1) >> (PAGE_SHIFT - QNX6_INODE_SIZE_BITS);
548 	offs = (ino - 1) & (~PAGE_MASK >> QNX6_INODE_SIZE_BITS);
549 	mapping = sbi->inodes->i_mapping;
550 	page = read_mapping_page(mapping, n, NULL);
551 	if (IS_ERR(page)) {
552 		pr_err("major problem: unable to read inode from dev %s\n",
553 		       sb->s_id);
554 		iget_failed(inode);
555 		return ERR_CAST(page);
556 	}
557 	kmap(page);
558 	raw_inode = ((struct qnx6_inode_entry *)page_address(page)) + offs;
559 
560 	inode->i_mode    = fs16_to_cpu(sbi, raw_inode->di_mode);
561 	i_uid_write(inode, (uid_t)fs32_to_cpu(sbi, raw_inode->di_uid));
562 	i_gid_write(inode, (gid_t)fs32_to_cpu(sbi, raw_inode->di_gid));
563 	inode->i_size    = fs64_to_cpu(sbi, raw_inode->di_size);
564 	inode->i_mtime.tv_sec   = fs32_to_cpu(sbi, raw_inode->di_mtime);
565 	inode->i_mtime.tv_nsec = 0;
566 	inode->i_atime.tv_sec   = fs32_to_cpu(sbi, raw_inode->di_atime);
567 	inode->i_atime.tv_nsec = 0;
568 	inode->i_ctime.tv_sec   = fs32_to_cpu(sbi, raw_inode->di_ctime);
569 	inode->i_ctime.tv_nsec = 0;
570 
571 	/* calc blocks based on 512 byte blocksize */
572 	inode->i_blocks = (inode->i_size + 511) >> 9;
573 
574 	memcpy(&ei->di_block_ptr, &raw_inode->di_block_ptr,
575 				sizeof(raw_inode->di_block_ptr));
576 	ei->di_filelevels = raw_inode->di_filelevels;
577 
578 	if (S_ISREG(inode->i_mode)) {
579 		inode->i_fop = &generic_ro_fops;
580 		inode->i_mapping->a_ops = &qnx6_aops;
581 	} else if (S_ISDIR(inode->i_mode)) {
582 		inode->i_op = &qnx6_dir_inode_operations;
583 		inode->i_fop = &qnx6_dir_operations;
584 		inode->i_mapping->a_ops = &qnx6_aops;
585 	} else if (S_ISLNK(inode->i_mode)) {
586 		inode->i_op = &page_symlink_inode_operations;
587 		inode_nohighmem(inode);
588 		inode->i_mapping->a_ops = &qnx6_aops;
589 	} else
590 		init_special_inode(inode, inode->i_mode, 0);
591 	qnx6_put_page(page);
592 	unlock_new_inode(inode);
593 	return inode;
594 }
595 
596 static struct kmem_cache *qnx6_inode_cachep;
597 
598 static struct inode *qnx6_alloc_inode(struct super_block *sb)
599 {
600 	struct qnx6_inode_info *ei;
601 	ei = kmem_cache_alloc(qnx6_inode_cachep, GFP_KERNEL);
602 	if (!ei)
603 		return NULL;
604 	return &ei->vfs_inode;
605 }
606 
607 static void qnx6_free_inode(struct inode *inode)
608 {
609 	kmem_cache_free(qnx6_inode_cachep, QNX6_I(inode));
610 }
611 
612 static void init_once(void *foo)
613 {
614 	struct qnx6_inode_info *ei = (struct qnx6_inode_info *) foo;
615 
616 	inode_init_once(&ei->vfs_inode);
617 }
618 
619 static int init_inodecache(void)
620 {
621 	qnx6_inode_cachep = kmem_cache_create("qnx6_inode_cache",
622 					     sizeof(struct qnx6_inode_info),
623 					     0, (SLAB_RECLAIM_ACCOUNT|
624 						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
625 					     init_once);
626 	if (!qnx6_inode_cachep)
627 		return -ENOMEM;
628 	return 0;
629 }
630 
631 static void destroy_inodecache(void)
632 {
633 	/*
634 	 * Make sure all delayed rcu free inodes are flushed before we
635 	 * destroy cache.
636 	 */
637 	rcu_barrier();
638 	kmem_cache_destroy(qnx6_inode_cachep);
639 }
640 
641 static struct dentry *qnx6_mount(struct file_system_type *fs_type,
642 	int flags, const char *dev_name, void *data)
643 {
644 	return mount_bdev(fs_type, flags, dev_name, data, qnx6_fill_super);
645 }
646 
647 static struct file_system_type qnx6_fs_type = {
648 	.owner		= THIS_MODULE,
649 	.name		= "qnx6",
650 	.mount		= qnx6_mount,
651 	.kill_sb	= kill_block_super,
652 	.fs_flags	= FS_REQUIRES_DEV,
653 };
654 MODULE_ALIAS_FS("qnx6");
655 
656 static int __init init_qnx6_fs(void)
657 {
658 	int err;
659 
660 	err = init_inodecache();
661 	if (err)
662 		return err;
663 
664 	err = register_filesystem(&qnx6_fs_type);
665 	if (err) {
666 		destroy_inodecache();
667 		return err;
668 	}
669 
670 	pr_info("QNX6 filesystem 1.0.0 registered.\n");
671 	return 0;
672 }
673 
674 static void __exit exit_qnx6_fs(void)
675 {
676 	unregister_filesystem(&qnx6_fs_type);
677 	destroy_inodecache();
678 }
679 
680 module_init(init_qnx6_fs)
681 module_exit(exit_qnx6_fs)
682 MODULE_LICENSE("GPL");
683