1 | /* Block- or MTD-based romfs |
2 | * |
3 | * Copyright © 2007 Red Hat, Inc. All Rights Reserved. |
4 | * Written by David Howells (dhowells@redhat.com) |
5 | * |
6 | * Derived from: ROMFS file system, Linux implementation |
7 | * |
8 | * Copyright © 1997-1999 Janos Farkas <chexum@shadow.banki.hu> |
9 | * |
10 | * Using parts of the minix filesystem |
11 | * Copyright © 1991, 1992 Linus Torvalds |
12 | * |
13 | * and parts of the affs filesystem additionally |
14 | * Copyright © 1993 Ray Burr |
15 | * Copyright © 1996 Hans-Joachim Widmaier |
16 | * |
17 | * Changes |
18 | * Changed for 2.1.19 modules |
19 | * Jan 1997 Initial release |
20 | * Jun 1997 2.1.43+ changes |
21 | * Proper page locking in read_folio |
22 | * Changed to work with 2.1.45+ fs |
23 | * Jul 1997 Fixed follow_link |
24 | * 2.1.47 |
25 | * lookup shouldn't return -ENOENT |
26 | * from Horst von Brand: |
27 | * fail on wrong checksum |
28 | * double unlock_super was possible |
29 | * correct namelen for statfs |
30 | * spotted by Bill Hawes: |
31 | * readlink shouldn't iput() |
32 | * Jun 1998 2.1.106 from Avery Pennarun: glibc scandir() |
33 | * exposed a problem in readdir |
34 | * 2.1.107 code-freeze spellchecker run |
35 | * Aug 1998 2.1.118+ VFS changes |
36 | * Sep 1998 2.1.122 another VFS change (follow_link) |
37 | * Apr 1999 2.2.7 no more EBADF checking in |
38 | * lookup/readdir, use ERR_PTR |
39 | * Jun 1999 2.3.6 d_alloc_root use changed |
40 | * 2.3.9 clean up usage of ENOENT/negative |
41 | * dentries in lookup |
42 | * clean up page flags setting |
43 | * (error, uptodate, locking) in |
44 | * in read_folio |
45 | * use init_special_inode for |
46 | * fifos/sockets (and streamline) in |
47 | * read_inode, fix _ops table order |
48 | * Aug 1999 2.3.16 __initfunc() => __init change |
49 | * Oct 1999 2.3.24 page->owner hack obsoleted |
50 | * Nov 1999 2.3.27 2.3.25+ page->offset => index change |
51 | * |
52 | * |
53 | * This program is free software; you can redistribute it and/or |
54 | * modify it under the terms of the GNU General Public Licence |
55 | * as published by the Free Software Foundation; either version |
56 | * 2 of the Licence, or (at your option) any later version. |
57 | */ |
58 | |
59 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
60 | |
61 | #include <linux/module.h> |
62 | #include <linux/string.h> |
63 | #include <linux/fs.h> |
64 | #include <linux/time.h> |
65 | #include <linux/slab.h> |
66 | #include <linux/init.h> |
67 | #include <linux/blkdev.h> |
68 | #include <linux/fs_context.h> |
69 | #include <linux/mount.h> |
70 | #include <linux/namei.h> |
71 | #include <linux/statfs.h> |
72 | #include <linux/mtd/super.h> |
73 | #include <linux/ctype.h> |
74 | #include <linux/highmem.h> |
75 | #include <linux/pagemap.h> |
76 | #include <linux/uaccess.h> |
77 | #include <linux/major.h> |
78 | #include "internal.h" |
79 | |
80 | static struct kmem_cache *romfs_inode_cachep; |
81 | |
82 | static const umode_t romfs_modemap[8] = { |
83 | 0, /* hard link */ |
84 | S_IFDIR | 0644, /* directory */ |
85 | S_IFREG | 0644, /* regular file */ |
86 | S_IFLNK | 0777, /* symlink */ |
87 | S_IFBLK | 0600, /* blockdev */ |
88 | S_IFCHR | 0600, /* chardev */ |
89 | S_IFSOCK | 0644, /* socket */ |
90 | S_IFIFO | 0644 /* FIFO */ |
91 | }; |
92 | |
93 | static const unsigned char romfs_dtype_table[] = { |
94 | DT_UNKNOWN, DT_DIR, DT_REG, DT_LNK, DT_BLK, DT_CHR, DT_SOCK, DT_FIFO |
95 | }; |
96 | |
97 | static struct inode *romfs_iget(struct super_block *sb, unsigned long pos); |
98 | |
99 | /* |
100 | * read a page worth of data from the image |
101 | */ |
102 | static int romfs_read_folio(struct file *file, struct folio *folio) |
103 | { |
104 | struct page *page = &folio->page; |
105 | struct inode *inode = page->mapping->host; |
106 | loff_t offset, size; |
107 | unsigned long fillsize, pos; |
108 | void *buf; |
109 | int ret; |
110 | |
111 | buf = kmap(page); |
112 | if (!buf) |
113 | return -ENOMEM; |
114 | |
115 | /* 32 bit warning -- but not for us :) */ |
116 | offset = page_offset(page); |
117 | size = i_size_read(inode); |
118 | fillsize = 0; |
119 | ret = 0; |
120 | if (offset < size) { |
121 | size -= offset; |
122 | fillsize = size > PAGE_SIZE ? PAGE_SIZE : size; |
123 | |
124 | pos = ROMFS_I(inode)->i_dataoffset + offset; |
125 | |
126 | ret = romfs_dev_read(sb: inode->i_sb, pos, buf, buflen: fillsize); |
127 | if (ret < 0) { |
128 | SetPageError(page); |
129 | fillsize = 0; |
130 | ret = -EIO; |
131 | } |
132 | } |
133 | |
134 | if (fillsize < PAGE_SIZE) |
135 | memset(buf + fillsize, 0, PAGE_SIZE - fillsize); |
136 | if (ret == 0) |
137 | SetPageUptodate(page); |
138 | |
139 | flush_dcache_page(page); |
140 | kunmap(page); |
141 | unlock_page(page); |
142 | return ret; |
143 | } |
144 | |
145 | static const struct address_space_operations romfs_aops = { |
146 | .read_folio = romfs_read_folio |
147 | }; |
148 | |
149 | /* |
150 | * read the entries from a directory |
151 | */ |
152 | static int romfs_readdir(struct file *file, struct dir_context *ctx) |
153 | { |
154 | struct inode *i = file_inode(f: file); |
155 | struct romfs_inode ri; |
156 | unsigned long offset, maxoff; |
157 | int j, ino, nextfh; |
158 | char fsname[ROMFS_MAXFN]; /* XXX dynamic? */ |
159 | int ret; |
160 | |
161 | maxoff = romfs_maxsize(sb: i->i_sb); |
162 | |
163 | offset = ctx->pos; |
164 | if (!offset) { |
165 | offset = i->i_ino & ROMFH_MASK; |
166 | ret = romfs_dev_read(sb: i->i_sb, pos: offset, buf: &ri, ROMFH_SIZE); |
167 | if (ret < 0) |
168 | goto out; |
169 | offset = be32_to_cpu(ri.spec) & ROMFH_MASK; |
170 | } |
171 | |
172 | /* Not really failsafe, but we are read-only... */ |
173 | for (;;) { |
174 | if (!offset || offset >= maxoff) { |
175 | offset = maxoff; |
176 | ctx->pos = offset; |
177 | goto out; |
178 | } |
179 | ctx->pos = offset; |
180 | |
181 | /* Fetch inode info */ |
182 | ret = romfs_dev_read(sb: i->i_sb, pos: offset, buf: &ri, ROMFH_SIZE); |
183 | if (ret < 0) |
184 | goto out; |
185 | |
186 | j = romfs_dev_strnlen(sb: i->i_sb, pos: offset + ROMFH_SIZE, |
187 | maxlen: sizeof(fsname) - 1); |
188 | if (j < 0) |
189 | goto out; |
190 | |
191 | ret = romfs_dev_read(sb: i->i_sb, pos: offset + ROMFH_SIZE, buf: fsname, buflen: j); |
192 | if (ret < 0) |
193 | goto out; |
194 | fsname[j] = '\0'; |
195 | |
196 | ino = offset; |
197 | nextfh = be32_to_cpu(ri.next); |
198 | if ((nextfh & ROMFH_TYPE) == ROMFH_HRD) |
199 | ino = be32_to_cpu(ri.spec); |
200 | if (!dir_emit(ctx, name: fsname, namelen: j, ino, |
201 | type: romfs_dtype_table[nextfh & ROMFH_TYPE])) |
202 | goto out; |
203 | |
204 | offset = nextfh & ROMFH_MASK; |
205 | } |
206 | out: |
207 | return 0; |
208 | } |
209 | |
210 | /* |
211 | * look up an entry in a directory |
212 | */ |
213 | static struct dentry *romfs_lookup(struct inode *dir, struct dentry *dentry, |
214 | unsigned int flags) |
215 | { |
216 | unsigned long offset, maxoff; |
217 | struct inode *inode = NULL; |
218 | struct romfs_inode ri; |
219 | const char *name; /* got from dentry */ |
220 | int len, ret; |
221 | |
222 | offset = dir->i_ino & ROMFH_MASK; |
223 | ret = romfs_dev_read(sb: dir->i_sb, pos: offset, buf: &ri, ROMFH_SIZE); |
224 | if (ret < 0) |
225 | goto error; |
226 | |
227 | /* search all the file entries in the list starting from the one |
228 | * pointed to by the directory's special data */ |
229 | maxoff = romfs_maxsize(sb: dir->i_sb); |
230 | offset = be32_to_cpu(ri.spec) & ROMFH_MASK; |
231 | |
232 | name = dentry->d_name.name; |
233 | len = dentry->d_name.len; |
234 | |
235 | for (;;) { |
236 | if (!offset || offset >= maxoff) |
237 | break; |
238 | |
239 | ret = romfs_dev_read(sb: dir->i_sb, pos: offset, buf: &ri, buflen: sizeof(ri)); |
240 | if (ret < 0) |
241 | goto error; |
242 | |
243 | /* try to match the first 16 bytes of name */ |
244 | ret = romfs_dev_strcmp(sb: dir->i_sb, pos: offset + ROMFH_SIZE, str: name, |
245 | size: len); |
246 | if (ret < 0) |
247 | goto error; |
248 | if (ret == 1) { |
249 | /* Hard link handling */ |
250 | if ((be32_to_cpu(ri.next) & ROMFH_TYPE) == ROMFH_HRD) |
251 | offset = be32_to_cpu(ri.spec) & ROMFH_MASK; |
252 | inode = romfs_iget(sb: dir->i_sb, pos: offset); |
253 | break; |
254 | } |
255 | |
256 | /* next entry */ |
257 | offset = be32_to_cpu(ri.next) & ROMFH_MASK; |
258 | } |
259 | |
260 | return d_splice_alias(inode, dentry); |
261 | error: |
262 | return ERR_PTR(error: ret); |
263 | } |
264 | |
265 | static const struct file_operations romfs_dir_operations = { |
266 | .read = generic_read_dir, |
267 | .iterate_shared = romfs_readdir, |
268 | .llseek = generic_file_llseek, |
269 | }; |
270 | |
271 | static const struct inode_operations romfs_dir_inode_operations = { |
272 | .lookup = romfs_lookup, |
273 | }; |
274 | |
275 | /* |
276 | * get a romfs inode based on its position in the image (which doubles as the |
277 | * inode number) |
278 | */ |
279 | static struct inode *romfs_iget(struct super_block *sb, unsigned long pos) |
280 | { |
281 | struct romfs_inode_info *inode; |
282 | struct romfs_inode ri; |
283 | struct inode *i; |
284 | unsigned long nlen; |
285 | unsigned nextfh; |
286 | int ret; |
287 | umode_t mode; |
288 | |
289 | /* we might have to traverse a chain of "hard link" file entries to get |
290 | * to the actual file */ |
291 | for (;;) { |
292 | ret = romfs_dev_read(sb, pos, buf: &ri, buflen: sizeof(ri)); |
293 | if (ret < 0) |
294 | goto error; |
295 | |
296 | /* XXX: do romfs_checksum here too (with name) */ |
297 | |
298 | nextfh = be32_to_cpu(ri.next); |
299 | if ((nextfh & ROMFH_TYPE) != ROMFH_HRD) |
300 | break; |
301 | |
302 | pos = be32_to_cpu(ri.spec) & ROMFH_MASK; |
303 | } |
304 | |
305 | /* determine the length of the filename */ |
306 | nlen = romfs_dev_strnlen(sb, pos: pos + ROMFH_SIZE, ROMFS_MAXFN); |
307 | if (IS_ERR_VALUE(nlen)) |
308 | goto eio; |
309 | |
310 | /* get an inode for this image position */ |
311 | i = iget_locked(sb, pos); |
312 | if (!i) |
313 | return ERR_PTR(error: -ENOMEM); |
314 | |
315 | if (!(i->i_state & I_NEW)) |
316 | return i; |
317 | |
318 | /* precalculate the data offset */ |
319 | inode = ROMFS_I(inode: i); |
320 | inode->i_metasize = (ROMFH_SIZE + nlen + 1 + ROMFH_PAD) & ROMFH_MASK; |
321 | inode->i_dataoffset = pos + inode->i_metasize; |
322 | |
323 | set_nlink(inode: i, nlink: 1); /* Hard to decide.. */ |
324 | i->i_size = be32_to_cpu(ri.size); |
325 | inode_set_mtime_to_ts(inode: i, |
326 | ts: inode_set_atime_to_ts(inode: i, ts: inode_set_ctime(inode: i, sec: 0, nsec: 0))); |
327 | |
328 | /* set up mode and ops */ |
329 | mode = romfs_modemap[nextfh & ROMFH_TYPE]; |
330 | |
331 | switch (nextfh & ROMFH_TYPE) { |
332 | case ROMFH_DIR: |
333 | i->i_size = ROMFS_I(inode: i)->i_metasize; |
334 | i->i_op = &romfs_dir_inode_operations; |
335 | i->i_fop = &romfs_dir_operations; |
336 | if (nextfh & ROMFH_EXEC) |
337 | mode |= S_IXUGO; |
338 | break; |
339 | case ROMFH_REG: |
340 | i->i_fop = &romfs_ro_fops; |
341 | i->i_data.a_ops = &romfs_aops; |
342 | if (nextfh & ROMFH_EXEC) |
343 | mode |= S_IXUGO; |
344 | break; |
345 | case ROMFH_SYM: |
346 | i->i_op = &page_symlink_inode_operations; |
347 | inode_nohighmem(inode: i); |
348 | i->i_data.a_ops = &romfs_aops; |
349 | mode |= S_IRWXUGO; |
350 | break; |
351 | default: |
352 | /* depending on MBZ for sock/fifos */ |
353 | nextfh = be32_to_cpu(ri.spec); |
354 | init_special_inode(i, mode, MKDEV(nextfh >> 16, |
355 | nextfh & 0xffff)); |
356 | break; |
357 | } |
358 | |
359 | i->i_mode = mode; |
360 | i->i_blocks = (i->i_size + 511) >> 9; |
361 | |
362 | unlock_new_inode(i); |
363 | return i; |
364 | |
365 | eio: |
366 | ret = -EIO; |
367 | error: |
368 | pr_err("read error for inode 0x%lx\n" , pos); |
369 | return ERR_PTR(error: ret); |
370 | } |
371 | |
372 | /* |
373 | * allocate a new inode |
374 | */ |
375 | static struct inode *romfs_alloc_inode(struct super_block *sb) |
376 | { |
377 | struct romfs_inode_info *inode; |
378 | |
379 | inode = alloc_inode_sb(sb, cache: romfs_inode_cachep, GFP_KERNEL); |
380 | return inode ? &inode->vfs_inode : NULL; |
381 | } |
382 | |
383 | /* |
384 | * return a spent inode to the slab cache |
385 | */ |
386 | static void romfs_free_inode(struct inode *inode) |
387 | { |
388 | kmem_cache_free(s: romfs_inode_cachep, objp: ROMFS_I(inode)); |
389 | } |
390 | |
391 | /* |
392 | * get filesystem statistics |
393 | */ |
394 | static int romfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
395 | { |
396 | struct super_block *sb = dentry->d_sb; |
397 | u64 id = 0; |
398 | |
399 | /* When calling huge_encode_dev(), |
400 | * use sb->s_bdev->bd_dev when, |
401 | * - CONFIG_ROMFS_ON_BLOCK defined |
402 | * use sb->s_dev when, |
403 | * - CONFIG_ROMFS_ON_BLOCK undefined and |
404 | * - CONFIG_ROMFS_ON_MTD defined |
405 | * leave id as 0 when, |
406 | * - CONFIG_ROMFS_ON_BLOCK undefined and |
407 | * - CONFIG_ROMFS_ON_MTD undefined |
408 | */ |
409 | if (sb->s_bdev) |
410 | id = huge_encode_dev(dev: sb->s_bdev->bd_dev); |
411 | else if (sb->s_dev) |
412 | id = huge_encode_dev(dev: sb->s_dev); |
413 | |
414 | buf->f_type = ROMFS_MAGIC; |
415 | buf->f_namelen = ROMFS_MAXFN; |
416 | buf->f_bsize = ROMBSIZE; |
417 | buf->f_bfree = buf->f_bavail = buf->f_ffree; |
418 | buf->f_blocks = |
419 | (romfs_maxsize(sb: dentry->d_sb) + ROMBSIZE - 1) >> ROMBSBITS; |
420 | buf->f_fsid = u64_to_fsid(v: id); |
421 | return 0; |
422 | } |
423 | |
424 | /* |
425 | * remounting must involve read-only |
426 | */ |
427 | static int romfs_reconfigure(struct fs_context *fc) |
428 | { |
429 | sync_filesystem(fc->root->d_sb); |
430 | fc->sb_flags |= SB_RDONLY; |
431 | return 0; |
432 | } |
433 | |
434 | static const struct super_operations romfs_super_ops = { |
435 | .alloc_inode = romfs_alloc_inode, |
436 | .free_inode = romfs_free_inode, |
437 | .statfs = romfs_statfs, |
438 | }; |
439 | |
440 | /* |
441 | * checksum check on part of a romfs filesystem |
442 | */ |
443 | static __u32 romfs_checksum(const void *data, int size) |
444 | { |
445 | const __be32 *ptr = data; |
446 | __u32 sum; |
447 | |
448 | sum = 0; |
449 | size >>= 2; |
450 | while (size > 0) { |
451 | sum += be32_to_cpu(*ptr++); |
452 | size--; |
453 | } |
454 | return sum; |
455 | } |
456 | |
457 | /* |
458 | * fill in the superblock |
459 | */ |
460 | static int romfs_fill_super(struct super_block *sb, struct fs_context *fc) |
461 | { |
462 | struct romfs_super_block *rsb; |
463 | struct inode *root; |
464 | unsigned long pos, img_size; |
465 | const char *storage; |
466 | size_t len; |
467 | int ret; |
468 | |
469 | #ifdef CONFIG_BLOCK |
470 | if (!sb->s_mtd) { |
471 | sb_set_blocksize(sb, ROMBSIZE); |
472 | } else { |
473 | sb->s_blocksize = ROMBSIZE; |
474 | sb->s_blocksize_bits = blksize_bits(ROMBSIZE); |
475 | } |
476 | #endif |
477 | |
478 | sb->s_maxbytes = 0xFFFFFFFF; |
479 | sb->s_magic = ROMFS_MAGIC; |
480 | sb->s_flags |= SB_RDONLY | SB_NOATIME; |
481 | sb->s_time_min = 0; |
482 | sb->s_time_max = 0; |
483 | sb->s_op = &romfs_super_ops; |
484 | |
485 | #ifdef CONFIG_ROMFS_ON_MTD |
486 | /* Use same dev ID from the underlying mtdblock device */ |
487 | if (sb->s_mtd) |
488 | sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, sb->s_mtd->index); |
489 | #endif |
490 | /* read the image superblock and check it */ |
491 | rsb = kmalloc(size: 512, GFP_KERNEL); |
492 | if (!rsb) |
493 | return -ENOMEM; |
494 | |
495 | sb->s_fs_info = (void *) 512; |
496 | ret = romfs_dev_read(sb, pos: 0, buf: rsb, buflen: 512); |
497 | if (ret < 0) |
498 | goto error_rsb; |
499 | |
500 | img_size = be32_to_cpu(rsb->size); |
501 | |
502 | if (sb->s_mtd && img_size > sb->s_mtd->size) |
503 | goto error_rsb_inval; |
504 | |
505 | sb->s_fs_info = (void *) img_size; |
506 | |
507 | if (rsb->word0 != ROMSB_WORD0 || rsb->word1 != ROMSB_WORD1 || |
508 | img_size < ROMFH_SIZE) { |
509 | if (!(fc->sb_flags & SB_SILENT)) |
510 | errorf(fc, "VFS: Can't find a romfs filesystem on dev %s.\n" , |
511 | sb->s_id); |
512 | goto error_rsb_inval; |
513 | } |
514 | |
515 | if (romfs_checksum(data: rsb, min_t(size_t, img_size, 512))) { |
516 | pr_err("bad initial checksum on dev %s.\n" , sb->s_id); |
517 | goto error_rsb_inval; |
518 | } |
519 | |
520 | storage = sb->s_mtd ? "MTD" : "the block layer" ; |
521 | |
522 | len = strnlen(p: rsb->name, ROMFS_MAXFN); |
523 | if (!(fc->sb_flags & SB_SILENT)) |
524 | pr_notice("Mounting image '%*.*s' through %s\n" , |
525 | (unsigned) len, (unsigned) len, rsb->name, storage); |
526 | |
527 | kfree(objp: rsb); |
528 | rsb = NULL; |
529 | |
530 | /* find the root directory */ |
531 | pos = (ROMFH_SIZE + len + 1 + ROMFH_PAD) & ROMFH_MASK; |
532 | |
533 | root = romfs_iget(sb, pos); |
534 | if (IS_ERR(ptr: root)) |
535 | return PTR_ERR(ptr: root); |
536 | |
537 | sb->s_root = d_make_root(root); |
538 | if (!sb->s_root) |
539 | return -ENOMEM; |
540 | |
541 | return 0; |
542 | |
543 | error_rsb_inval: |
544 | ret = -EINVAL; |
545 | error_rsb: |
546 | kfree(objp: rsb); |
547 | return ret; |
548 | } |
549 | |
550 | /* |
551 | * get a superblock for mounting |
552 | */ |
553 | static int romfs_get_tree(struct fs_context *fc) |
554 | { |
555 | int ret = -EINVAL; |
556 | |
557 | #ifdef CONFIG_ROMFS_ON_MTD |
558 | ret = get_tree_mtd(fc, romfs_fill_super); |
559 | #endif |
560 | #ifdef CONFIG_ROMFS_ON_BLOCK |
561 | if (ret == -EINVAL) |
562 | ret = get_tree_bdev(fc, fill_super: romfs_fill_super); |
563 | #endif |
564 | return ret; |
565 | } |
566 | |
567 | static const struct fs_context_operations romfs_context_ops = { |
568 | .get_tree = romfs_get_tree, |
569 | .reconfigure = romfs_reconfigure, |
570 | }; |
571 | |
572 | /* |
573 | * Set up the filesystem mount context. |
574 | */ |
575 | static int romfs_init_fs_context(struct fs_context *fc) |
576 | { |
577 | fc->ops = &romfs_context_ops; |
578 | return 0; |
579 | } |
580 | |
581 | /* |
582 | * destroy a romfs superblock in the appropriate manner |
583 | */ |
584 | static void romfs_kill_sb(struct super_block *sb) |
585 | { |
586 | generic_shutdown_super(sb); |
587 | |
588 | #ifdef CONFIG_ROMFS_ON_MTD |
589 | if (sb->s_mtd) { |
590 | put_mtd_device(sb->s_mtd); |
591 | sb->s_mtd = NULL; |
592 | } |
593 | #endif |
594 | #ifdef CONFIG_ROMFS_ON_BLOCK |
595 | if (sb->s_bdev) { |
596 | sync_blockdev(bdev: sb->s_bdev); |
597 | bdev_release(handle: sb->s_bdev_handle); |
598 | } |
599 | #endif |
600 | } |
601 | |
602 | static struct file_system_type romfs_fs_type = { |
603 | .owner = THIS_MODULE, |
604 | .name = "romfs" , |
605 | .init_fs_context = romfs_init_fs_context, |
606 | .kill_sb = romfs_kill_sb, |
607 | .fs_flags = FS_REQUIRES_DEV, |
608 | }; |
609 | MODULE_ALIAS_FS("romfs" ); |
610 | |
611 | /* |
612 | * inode storage initialiser |
613 | */ |
614 | static void romfs_i_init_once(void *_inode) |
615 | { |
616 | struct romfs_inode_info *inode = _inode; |
617 | |
618 | inode_init_once(&inode->vfs_inode); |
619 | } |
620 | |
621 | /* |
622 | * romfs module initialisation |
623 | */ |
624 | static int __init init_romfs_fs(void) |
625 | { |
626 | int ret; |
627 | |
628 | pr_info("ROMFS MTD (C) 2007 Red Hat, Inc.\n" ); |
629 | |
630 | romfs_inode_cachep = |
631 | kmem_cache_create(name: "romfs_i" , |
632 | size: sizeof(struct romfs_inode_info), align: 0, |
633 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | |
634 | SLAB_ACCOUNT, ctor: romfs_i_init_once); |
635 | |
636 | if (!romfs_inode_cachep) { |
637 | pr_err("Failed to initialise inode cache\n" ); |
638 | return -ENOMEM; |
639 | } |
640 | ret = register_filesystem(&romfs_fs_type); |
641 | if (ret) { |
642 | pr_err("Failed to register filesystem\n" ); |
643 | goto error_register; |
644 | } |
645 | return 0; |
646 | |
647 | error_register: |
648 | kmem_cache_destroy(s: romfs_inode_cachep); |
649 | return ret; |
650 | } |
651 | |
652 | /* |
653 | * romfs module removal |
654 | */ |
655 | static void __exit exit_romfs_fs(void) |
656 | { |
657 | unregister_filesystem(&romfs_fs_type); |
658 | /* |
659 | * Make sure all delayed rcu free inodes are flushed before we |
660 | * destroy cache. |
661 | */ |
662 | rcu_barrier(); |
663 | kmem_cache_destroy(s: romfs_inode_cachep); |
664 | } |
665 | |
666 | module_init(init_romfs_fs); |
667 | module_exit(exit_romfs_fs); |
668 | |
669 | MODULE_DESCRIPTION("Direct-MTD Capable RomFS" ); |
670 | MODULE_AUTHOR("Red Hat, Inc." ); |
671 | MODULE_LICENSE("GPL" ); /* Actually dual-licensed, but it doesn't matter for */ |
672 | |