Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * ROMFS file system, Linux implementation | |
3 | * | |
4 | * Copyright (C) 1997-1999 Janos Farkas <chexum@shadow.banki.hu> | |
5 | * | |
6 | * Using parts of the minix filesystem | |
7 | * Copyright (C) 1991, 1992 Linus Torvalds | |
8 | * | |
9 | * and parts of the affs filesystem additionally | |
10 | * Copyright (C) 1993 Ray Burr | |
11 | * Copyright (C) 1996 Hans-Joachim Widmaier | |
12 | * | |
13 | * This program is free software; you can redistribute it and/or | |
14 | * modify it under the terms of the GNU General Public License | |
15 | * as published by the Free Software Foundation; either version | |
16 | * 2 of the License, or (at your option) any later version. | |
17 | * | |
18 | * Changes | |
19 | * Changed for 2.1.19 modules | |
20 | * Jan 1997 Initial release | |
21 | * Jun 1997 2.1.43+ changes | |
22 | * Proper page locking in readpage | |
23 | * Changed to work with 2.1.45+ fs | |
24 | * Jul 1997 Fixed follow_link | |
25 | * 2.1.47 | |
26 | * lookup shouldn't return -ENOENT | |
27 | * from Horst von Brand: | |
28 | * fail on wrong checksum | |
29 | * double unlock_super was possible | |
30 | * correct namelen for statfs | |
31 | * spotted by Bill Hawes: | |
32 | * readlink shouldn't iput() | |
33 | * Jun 1998 2.1.106 from Avery Pennarun: glibc scandir() | |
34 | * exposed a problem in readdir | |
35 | * 2.1.107 code-freeze spellchecker run | |
36 | * Aug 1998 2.1.118+ VFS changes | |
37 | * Sep 1998 2.1.122 another VFS change (follow_link) | |
38 | * Apr 1999 2.2.7 no more EBADF checking in | |
39 | * lookup/readdir, use ERR_PTR | |
40 | * Jun 1999 2.3.6 d_alloc_root use changed | |
41 | * 2.3.9 clean up usage of ENOENT/negative | |
42 | * dentries in lookup | |
43 | * clean up page flags setting | |
44 | * (error, uptodate, locking) in | |
45 | * in readpage | |
46 | * use init_special_inode for | |
47 | * fifos/sockets (and streamline) in | |
48 | * read_inode, fix _ops table order | |
49 | * Aug 1999 2.3.16 __initfunc() => __init change | |
50 | * Oct 1999 2.3.24 page->owner hack obsoleted | |
51 | * Nov 1999 2.3.27 2.3.25+ page->offset => index change | |
52 | */ | |
53 | ||
54 | /* todo: | |
55 | * - see Documentation/filesystems/romfs.txt | |
56 | * - use allocated, not stack memory for file names? | |
57 | * - considering write access... | |
58 | * - network (tftp) files? | |
59 | * - merge back some _op tables | |
60 | */ | |
61 | ||
62 | /* | |
63 | * Sorry about some optimizations and for some goto's. I just wanted | |
64 | * to squeeze some more bytes out of this code.. :) | |
65 | */ | |
66 | ||
67 | #include <linux/module.h> | |
68 | #include <linux/types.h> | |
69 | #include <linux/errno.h> | |
70 | #include <linux/slab.h> | |
71 | #include <linux/romfs_fs.h> | |
72 | #include <linux/fs.h> | |
73 | #include <linux/init.h> | |
74 | #include <linux/pagemap.h> | |
75 | #include <linux/smp_lock.h> | |
76 | #include <linux/buffer_head.h> | |
77 | #include <linux/vfs.h> | |
78 | ||
79 | #include <asm/uaccess.h> | |
80 | ||
81 | struct romfs_inode_info { | |
82 | unsigned long i_metasize; /* size of non-data area */ | |
83 | unsigned long i_dataoffset; /* from the start of fs */ | |
84 | struct inode vfs_inode; | |
85 | }; | |
86 | ||
78cc9120 DH |
87 | static struct inode *romfs_iget(struct super_block *, unsigned long); |
88 | ||
1da177e4 LT |
89 | /* instead of private superblock data */ |
90 | static inline unsigned long romfs_maxsize(struct super_block *sb) | |
91 | { | |
92 | return (unsigned long)sb->s_fs_info; | |
93 | } | |
94 | ||
95 | static inline struct romfs_inode_info *ROMFS_I(struct inode *inode) | |
96 | { | |
55ca3e79 | 97 | return container_of(inode, struct romfs_inode_info, vfs_inode); |
1da177e4 LT |
98 | } |
99 | ||
100 | static __u32 | |
101 | romfs_checksum(void *data, int size) | |
102 | { | |
103 | __u32 sum; | |
104 | __be32 *ptr; | |
105 | ||
106 | sum = 0; ptr = data; | |
107 | size>>=2; | |
108 | while (size>0) { | |
109 | sum += be32_to_cpu(*ptr++); | |
110 | size--; | |
111 | } | |
112 | return sum; | |
113 | } | |
114 | ||
ee9b6d61 | 115 | static const struct super_operations romfs_ops; |
1da177e4 LT |
116 | |
117 | static int romfs_fill_super(struct super_block *s, void *data, int silent) | |
118 | { | |
119 | struct buffer_head *bh; | |
120 | struct romfs_super_block *rsb; | |
121 | struct inode *root; | |
78cc9120 | 122 | int sz, ret = -EINVAL; |
1da177e4 LT |
123 | |
124 | /* I would parse the options here, but there are none.. :) */ | |
125 | ||
126 | sb_set_blocksize(s, ROMBSIZE); | |
127 | s->s_maxbytes = 0xFFFFFFFF; | |
128 | ||
129 | bh = sb_bread(s, 0); | |
130 | if (!bh) { | |
131 | /* XXX merge with other printk? */ | |
132 | printk ("romfs: unable to read superblock\n"); | |
133 | goto outnobh; | |
134 | } | |
135 | ||
136 | rsb = (struct romfs_super_block *)bh->b_data; | |
137 | sz = be32_to_cpu(rsb->size); | |
138 | if (rsb->word0 != ROMSB_WORD0 || rsb->word1 != ROMSB_WORD1 | |
139 | || sz < ROMFH_SIZE) { | |
140 | if (!silent) | |
141 | printk ("VFS: Can't find a romfs filesystem on dev " | |
142 | "%s.\n", s->s_id); | |
143 | goto out; | |
144 | } | |
145 | if (romfs_checksum(rsb, min_t(int, sz, 512))) { | |
146 | printk ("romfs: bad initial checksum on dev " | |
147 | "%s.\n", s->s_id); | |
148 | goto out; | |
149 | } | |
150 | ||
151 | s->s_magic = ROMFS_MAGIC; | |
152 | s->s_fs_info = (void *)(long)sz; | |
153 | ||
154 | s->s_flags |= MS_RDONLY; | |
155 | ||
156 | /* Find the start of the fs */ | |
157 | sz = (ROMFH_SIZE + | |
158 | strnlen(rsb->name, ROMFS_MAXFN) + 1 + ROMFH_PAD) | |
159 | & ROMFH_MASK; | |
160 | ||
161 | s->s_op = &romfs_ops; | |
78cc9120 DH |
162 | root = romfs_iget(s, sz); |
163 | if (IS_ERR(root)) { | |
164 | ret = PTR_ERR(root); | |
1da177e4 | 165 | goto out; |
78cc9120 | 166 | } |
1da177e4 | 167 | |
78cc9120 | 168 | ret = -ENOMEM; |
1da177e4 LT |
169 | s->s_root = d_alloc_root(root); |
170 | if (!s->s_root) | |
171 | goto outiput; | |
172 | ||
173 | brelse(bh); | |
174 | return 0; | |
175 | ||
176 | outiput: | |
177 | iput(root); | |
178 | out: | |
179 | brelse(bh); | |
180 | outnobh: | |
78cc9120 | 181 | return ret; |
1da177e4 LT |
182 | } |
183 | ||
184 | /* That's simple too. */ | |
185 | ||
186 | static int | |
726c3342 | 187 | romfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 LT |
188 | { |
189 | buf->f_type = ROMFS_MAGIC; | |
190 | buf->f_bsize = ROMBSIZE; | |
191 | buf->f_bfree = buf->f_bavail = buf->f_ffree; | |
726c3342 | 192 | buf->f_blocks = (romfs_maxsize(dentry->d_sb)+ROMBSIZE-1)>>ROMBSBITS; |
1da177e4 LT |
193 | buf->f_namelen = ROMFS_MAXFN; |
194 | return 0; | |
195 | } | |
196 | ||
197 | /* some helper routines */ | |
198 | ||
199 | static int | |
200 | romfs_strnlen(struct inode *i, unsigned long offset, unsigned long count) | |
201 | { | |
202 | struct buffer_head *bh; | |
203 | unsigned long avail, maxsize, res; | |
204 | ||
205 | maxsize = romfs_maxsize(i->i_sb); | |
206 | if (offset >= maxsize) | |
207 | return -1; | |
208 | ||
209 | /* strnlen is almost always valid */ | |
210 | if (count > maxsize || offset+count > maxsize) | |
211 | count = maxsize-offset; | |
212 | ||
213 | bh = sb_bread(i->i_sb, offset>>ROMBSBITS); | |
214 | if (!bh) | |
215 | return -1; /* error */ | |
216 | ||
217 | avail = ROMBSIZE - (offset & ROMBMASK); | |
218 | maxsize = min_t(unsigned long, count, avail); | |
219 | res = strnlen(((char *)bh->b_data)+(offset&ROMBMASK), maxsize); | |
220 | brelse(bh); | |
221 | ||
222 | if (res < maxsize) | |
223 | return res; /* found all of it */ | |
224 | ||
225 | while (res < count) { | |
226 | offset += maxsize; | |
227 | ||
228 | bh = sb_bread(i->i_sb, offset>>ROMBSBITS); | |
229 | if (!bh) | |
230 | return -1; | |
231 | maxsize = min_t(unsigned long, count - res, ROMBSIZE); | |
232 | avail = strnlen(bh->b_data, maxsize); | |
233 | res += avail; | |
234 | brelse(bh); | |
235 | if (avail < maxsize) | |
236 | return res; | |
237 | } | |
238 | return res; | |
239 | } | |
240 | ||
241 | static int | |
242 | romfs_copyfrom(struct inode *i, void *dest, unsigned long offset, unsigned long count) | |
243 | { | |
244 | struct buffer_head *bh; | |
245 | unsigned long avail, maxsize, res; | |
246 | ||
247 | maxsize = romfs_maxsize(i->i_sb); | |
248 | if (offset >= maxsize || count > maxsize || offset+count>maxsize) | |
249 | return -1; | |
250 | ||
251 | bh = sb_bread(i->i_sb, offset>>ROMBSBITS); | |
252 | if (!bh) | |
253 | return -1; /* error */ | |
254 | ||
255 | avail = ROMBSIZE - (offset & ROMBMASK); | |
256 | maxsize = min_t(unsigned long, count, avail); | |
257 | memcpy(dest, ((char *)bh->b_data) + (offset & ROMBMASK), maxsize); | |
258 | brelse(bh); | |
259 | ||
260 | res = maxsize; /* all of it */ | |
261 | ||
262 | while (res < count) { | |
263 | offset += maxsize; | |
264 | dest += maxsize; | |
265 | ||
266 | bh = sb_bread(i->i_sb, offset>>ROMBSBITS); | |
267 | if (!bh) | |
268 | return -1; | |
269 | maxsize = min_t(unsigned long, count - res, ROMBSIZE); | |
270 | memcpy(dest, bh->b_data, maxsize); | |
271 | brelse(bh); | |
272 | res += maxsize; | |
273 | } | |
274 | return res; | |
275 | } | |
276 | ||
277 | static unsigned char romfs_dtype_table[] = { | |
278 | DT_UNKNOWN, DT_DIR, DT_REG, DT_LNK, DT_BLK, DT_CHR, DT_SOCK, DT_FIFO | |
279 | }; | |
280 | ||
281 | static int | |
282 | romfs_readdir(struct file *filp, void *dirent, filldir_t filldir) | |
283 | { | |
3027795e | 284 | struct inode *i = filp->f_path.dentry->d_inode; |
1da177e4 LT |
285 | struct romfs_inode ri; |
286 | unsigned long offset, maxoff; | |
287 | int j, ino, nextfh; | |
288 | int stored = 0; | |
289 | char fsname[ROMFS_MAXFN]; /* XXX dynamic? */ | |
290 | ||
291 | lock_kernel(); | |
292 | ||
293 | maxoff = romfs_maxsize(i->i_sb); | |
294 | ||
295 | offset = filp->f_pos; | |
296 | if (!offset) { | |
297 | offset = i->i_ino & ROMFH_MASK; | |
298 | if (romfs_copyfrom(i, &ri, offset, ROMFH_SIZE) <= 0) | |
299 | goto out; | |
300 | offset = be32_to_cpu(ri.spec) & ROMFH_MASK; | |
301 | } | |
302 | ||
303 | /* Not really failsafe, but we are read-only... */ | |
304 | for(;;) { | |
305 | if (!offset || offset >= maxoff) { | |
306 | offset = maxoff; | |
307 | filp->f_pos = offset; | |
308 | goto out; | |
309 | } | |
310 | filp->f_pos = offset; | |
311 | ||
312 | /* Fetch inode info */ | |
313 | if (romfs_copyfrom(i, &ri, offset, ROMFH_SIZE) <= 0) | |
314 | goto out; | |
315 | ||
316 | j = romfs_strnlen(i, offset+ROMFH_SIZE, sizeof(fsname)-1); | |
317 | if (j < 0) | |
318 | goto out; | |
319 | ||
320 | fsname[j]=0; | |
321 | romfs_copyfrom(i, fsname, offset+ROMFH_SIZE, j); | |
322 | ||
323 | ino = offset; | |
324 | nextfh = be32_to_cpu(ri.next); | |
325 | if ((nextfh & ROMFH_TYPE) == ROMFH_HRD) | |
326 | ino = be32_to_cpu(ri.spec); | |
327 | if (filldir(dirent, fsname, j, offset, ino, | |
328 | romfs_dtype_table[nextfh & ROMFH_TYPE]) < 0) { | |
329 | goto out; | |
330 | } | |
331 | stored++; | |
332 | offset = nextfh & ROMFH_MASK; | |
333 | } | |
334 | out: | |
335 | unlock_kernel(); | |
336 | return stored; | |
337 | } | |
338 | ||
339 | static struct dentry * | |
340 | romfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) | |
341 | { | |
342 | unsigned long offset, maxoff; | |
4ebf8984 DH |
343 | long res; |
344 | int fslen; | |
345 | struct inode *inode = NULL; | |
1da177e4 LT |
346 | char fsname[ROMFS_MAXFN]; /* XXX dynamic? */ |
347 | struct romfs_inode ri; | |
348 | const char *name; /* got from dentry */ | |
349 | int len; | |
350 | ||
351 | res = -EACCES; /* placeholder for "no data here" */ | |
352 | offset = dir->i_ino & ROMFH_MASK; | |
353 | lock_kernel(); | |
354 | if (romfs_copyfrom(dir, &ri, offset, ROMFH_SIZE) <= 0) | |
4ebf8984 | 355 | goto error; |
1da177e4 LT |
356 | |
357 | maxoff = romfs_maxsize(dir->i_sb); | |
358 | offset = be32_to_cpu(ri.spec) & ROMFH_MASK; | |
359 | ||
360 | /* OK, now find the file whose name is in "dentry" in the | |
361 | * directory specified by "dir". */ | |
362 | ||
363 | name = dentry->d_name.name; | |
364 | len = dentry->d_name.len; | |
365 | ||
366 | for(;;) { | |
367 | if (!offset || offset >= maxoff) | |
4ebf8984 | 368 | goto success; /* negative success */ |
1da177e4 | 369 | if (romfs_copyfrom(dir, &ri, offset, ROMFH_SIZE) <= 0) |
4ebf8984 | 370 | goto error; |
1da177e4 LT |
371 | |
372 | /* try to match the first 16 bytes of name */ | |
373 | fslen = romfs_strnlen(dir, offset+ROMFH_SIZE, ROMFH_SIZE); | |
374 | if (len < ROMFH_SIZE) { | |
375 | if (len == fslen) { | |
376 | /* both are shorter, and same size */ | |
377 | romfs_copyfrom(dir, fsname, offset+ROMFH_SIZE, len+1); | |
378 | if (strncmp (name, fsname, len) == 0) | |
379 | break; | |
380 | } | |
381 | } else if (fslen >= ROMFH_SIZE) { | |
382 | /* both are longer; XXX optimize max size */ | |
383 | fslen = romfs_strnlen(dir, offset+ROMFH_SIZE, sizeof(fsname)-1); | |
384 | if (len == fslen) { | |
385 | romfs_copyfrom(dir, fsname, offset+ROMFH_SIZE, len+1); | |
386 | if (strncmp(name, fsname, len) == 0) | |
387 | break; | |
388 | } | |
389 | } | |
390 | /* next entry */ | |
391 | offset = be32_to_cpu(ri.next) & ROMFH_MASK; | |
392 | } | |
393 | ||
394 | /* Hard link handling */ | |
395 | if ((be32_to_cpu(ri.next) & ROMFH_TYPE) == ROMFH_HRD) | |
396 | offset = be32_to_cpu(ri.spec) & ROMFH_MASK; | |
397 | ||
78cc9120 DH |
398 | inode = romfs_iget(dir->i_sb, offset); |
399 | if (IS_ERR(inode)) { | |
400 | res = PTR_ERR(inode); | |
4ebf8984 | 401 | goto error; |
78cc9120 | 402 | } |
1da177e4 | 403 | |
4ebf8984 DH |
404 | success: |
405 | d_add(dentry, inode); | |
78cc9120 | 406 | res = 0; |
4ebf8984 DH |
407 | error: |
408 | unlock_kernel(); | |
1da177e4 LT |
409 | return ERR_PTR(res); |
410 | } | |
411 | ||
412 | /* | |
413 | * Ok, we do readpage, to be able to execute programs. Unfortunately, | |
414 | * we can't use bmap, since we may have looser alignments. | |
415 | */ | |
416 | ||
417 | static int | |
418 | romfs_readpage(struct file *file, struct page * page) | |
419 | { | |
420 | struct inode *inode = page->mapping->host; | |
54b21a79 | 421 | loff_t offset, avail, readlen; |
1da177e4 LT |
422 | void *buf; |
423 | int result = -EIO; | |
424 | ||
425 | page_cache_get(page); | |
426 | lock_kernel(); | |
427 | buf = kmap(page); | |
428 | if (!buf) | |
429 | goto err_out; | |
430 | ||
431 | /* 32 bit warning -- but not for us :) */ | |
54b21a79 AM |
432 | offset = page_offset(page); |
433 | if (offset < i_size_read(inode)) { | |
1da177e4 LT |
434 | avail = inode->i_size-offset; |
435 | readlen = min_t(unsigned long, avail, PAGE_SIZE); | |
436 | if (romfs_copyfrom(inode, buf, ROMFS_I(inode)->i_dataoffset+offset, readlen) == readlen) { | |
437 | if (readlen < PAGE_SIZE) { | |
438 | memset(buf + readlen,0,PAGE_SIZE-readlen); | |
439 | } | |
440 | SetPageUptodate(page); | |
441 | result = 0; | |
442 | } | |
443 | } | |
444 | if (result) { | |
445 | memset(buf, 0, PAGE_SIZE); | |
446 | SetPageError(page); | |
447 | } | |
448 | flush_dcache_page(page); | |
449 | ||
450 | unlock_page(page); | |
451 | ||
452 | kunmap(page); | |
453 | err_out: | |
454 | page_cache_release(page); | |
455 | unlock_kernel(); | |
456 | ||
457 | return result; | |
458 | } | |
459 | ||
460 | /* Mapping from our types to the kernel */ | |
461 | ||
f5e54d6e | 462 | static const struct address_space_operations romfs_aops = { |
1da177e4 LT |
463 | .readpage = romfs_readpage |
464 | }; | |
465 | ||
4b6f5d20 | 466 | static const struct file_operations romfs_dir_operations = { |
1da177e4 LT |
467 | .read = generic_read_dir, |
468 | .readdir = romfs_readdir, | |
469 | }; | |
470 | ||
c5ef1c42 | 471 | static const struct inode_operations romfs_dir_inode_operations = { |
1da177e4 LT |
472 | .lookup = romfs_lookup, |
473 | }; | |
474 | ||
475 | static mode_t romfs_modemap[] = | |
476 | { | |
477 | 0, S_IFDIR+0644, S_IFREG+0644, S_IFLNK+0777, | |
478 | S_IFBLK+0600, S_IFCHR+0600, S_IFSOCK+0644, S_IFIFO+0644 | |
479 | }; | |
480 | ||
78cc9120 DH |
481 | static struct inode * |
482 | romfs_iget(struct super_block *sb, unsigned long ino) | |
1da177e4 | 483 | { |
78cc9120 | 484 | int nextfh; |
1da177e4 | 485 | struct romfs_inode ri; |
78cc9120 DH |
486 | struct inode *i; |
487 | ||
488 | ino &= ROMFH_MASK; | |
489 | i = iget_locked(sb, ino); | |
490 | if (!i) | |
491 | return ERR_PTR(-ENOMEM); | |
492 | if (!(i->i_state & I_NEW)) | |
493 | return i; | |
1da177e4 | 494 | |
1da177e4 LT |
495 | i->i_mode = 0; |
496 | ||
497 | /* Loop for finding the real hard link */ | |
498 | for(;;) { | |
499 | if (romfs_copyfrom(i, &ri, ino, ROMFH_SIZE) <= 0) { | |
78cc9120 DH |
500 | printk(KERN_ERR "romfs: read error for inode 0x%lx\n", |
501 | ino); | |
502 | iget_failed(i); | |
503 | return ERR_PTR(-EIO); | |
1da177e4 LT |
504 | } |
505 | /* XXX: do romfs_checksum here too (with name) */ | |
506 | ||
507 | nextfh = be32_to_cpu(ri.next); | |
508 | if ((nextfh & ROMFH_TYPE) != ROMFH_HRD) | |
509 | break; | |
510 | ||
511 | ino = be32_to_cpu(ri.spec) & ROMFH_MASK; | |
512 | } | |
513 | ||
514 | i->i_nlink = 1; /* Hard to decide.. */ | |
515 | i->i_size = be32_to_cpu(ri.size); | |
516 | i->i_mtime.tv_sec = i->i_atime.tv_sec = i->i_ctime.tv_sec = 0; | |
517 | i->i_mtime.tv_nsec = i->i_atime.tv_nsec = i->i_ctime.tv_nsec = 0; | |
518 | i->i_uid = i->i_gid = 0; | |
519 | ||
520 | /* Precalculate the data offset */ | |
521 | ino = romfs_strnlen(i, ino+ROMFH_SIZE, ROMFS_MAXFN); | |
522 | if (ino >= 0) | |
523 | ino = ((ROMFH_SIZE+ino+1+ROMFH_PAD)&ROMFH_MASK); | |
524 | else | |
525 | ino = 0; | |
526 | ||
527 | ROMFS_I(i)->i_metasize = ino; | |
528 | ROMFS_I(i)->i_dataoffset = ino+(i->i_ino&ROMFH_MASK); | |
529 | ||
530 | /* Compute permissions */ | |
531 | ino = romfs_modemap[nextfh & ROMFH_TYPE]; | |
532 | /* only "normal" files have ops */ | |
533 | switch (nextfh & ROMFH_TYPE) { | |
534 | case 1: | |
535 | i->i_size = ROMFS_I(i)->i_metasize; | |
536 | i->i_op = &romfs_dir_inode_operations; | |
537 | i->i_fop = &romfs_dir_operations; | |
538 | if (nextfh & ROMFH_EXEC) | |
539 | ino |= S_IXUGO; | |
540 | i->i_mode = ino; | |
541 | break; | |
542 | case 2: | |
543 | i->i_fop = &generic_ro_fops; | |
544 | i->i_data.a_ops = &romfs_aops; | |
545 | if (nextfh & ROMFH_EXEC) | |
546 | ino |= S_IXUGO; | |
547 | i->i_mode = ino; | |
548 | break; | |
549 | case 3: | |
550 | i->i_op = &page_symlink_inode_operations; | |
551 | i->i_data.a_ops = &romfs_aops; | |
552 | i->i_mode = ino | S_IRWXUGO; | |
553 | break; | |
554 | default: | |
555 | /* depending on MBZ for sock/fifos */ | |
556 | nextfh = be32_to_cpu(ri.spec); | |
557 | init_special_inode(i, ino, | |
558 | MKDEV(nextfh>>16,nextfh&0xffff)); | |
559 | } | |
78cc9120 DH |
560 | unlock_new_inode(i); |
561 | return i; | |
1da177e4 LT |
562 | } |
563 | ||
e18b890b | 564 | static struct kmem_cache * romfs_inode_cachep; |
1da177e4 LT |
565 | |
566 | static struct inode *romfs_alloc_inode(struct super_block *sb) | |
567 | { | |
568 | struct romfs_inode_info *ei; | |
55ca3e79 | 569 | ei = kmem_cache_alloc(romfs_inode_cachep, GFP_KERNEL); |
1da177e4 LT |
570 | if (!ei) |
571 | return NULL; | |
572 | return &ei->vfs_inode; | |
573 | } | |
574 | ||
575 | static void romfs_destroy_inode(struct inode *inode) | |
576 | { | |
577 | kmem_cache_free(romfs_inode_cachep, ROMFS_I(inode)); | |
578 | } | |
579 | ||
51cc5068 | 580 | static void init_once(void *foo) |
1da177e4 | 581 | { |
a35afb83 | 582 | struct romfs_inode_info *ei = foo; |
1da177e4 | 583 | |
a35afb83 | 584 | inode_init_once(&ei->vfs_inode); |
1da177e4 | 585 | } |
20c2df83 | 586 | |
1da177e4 LT |
587 | static int init_inodecache(void) |
588 | { | |
589 | romfs_inode_cachep = kmem_cache_create("romfs_inode_cache", | |
590 | sizeof(struct romfs_inode_info), | |
fffb60f9 PJ |
591 | 0, (SLAB_RECLAIM_ACCOUNT| |
592 | SLAB_MEM_SPREAD), | |
20c2df83 | 593 | init_once); |
1da177e4 LT |
594 | if (romfs_inode_cachep == NULL) |
595 | return -ENOMEM; | |
596 | return 0; | |
597 | } | |
598 | ||
599 | static void destroy_inodecache(void) | |
600 | { | |
1a1d92c1 | 601 | kmem_cache_destroy(romfs_inode_cachep); |
1da177e4 LT |
602 | } |
603 | ||
604 | static int romfs_remount(struct super_block *sb, int *flags, char *data) | |
605 | { | |
606 | *flags |= MS_RDONLY; | |
607 | return 0; | |
608 | } | |
609 | ||
ee9b6d61 | 610 | static const struct super_operations romfs_ops = { |
1da177e4 LT |
611 | .alloc_inode = romfs_alloc_inode, |
612 | .destroy_inode = romfs_destroy_inode, | |
1da177e4 LT |
613 | .statfs = romfs_statfs, |
614 | .remount_fs = romfs_remount, | |
615 | }; | |
616 | ||
454e2398 DH |
617 | static int romfs_get_sb(struct file_system_type *fs_type, |
618 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) | |
1da177e4 | 619 | { |
454e2398 DH |
620 | return get_sb_bdev(fs_type, flags, dev_name, data, romfs_fill_super, |
621 | mnt); | |
1da177e4 LT |
622 | } |
623 | ||
624 | static struct file_system_type romfs_fs_type = { | |
625 | .owner = THIS_MODULE, | |
626 | .name = "romfs", | |
627 | .get_sb = romfs_get_sb, | |
628 | .kill_sb = kill_block_super, | |
629 | .fs_flags = FS_REQUIRES_DEV, | |
630 | }; | |
631 | ||
632 | static int __init init_romfs_fs(void) | |
633 | { | |
634 | int err = init_inodecache(); | |
635 | if (err) | |
636 | goto out1; | |
637 | err = register_filesystem(&romfs_fs_type); | |
638 | if (err) | |
639 | goto out; | |
640 | return 0; | |
641 | out: | |
642 | destroy_inodecache(); | |
643 | out1: | |
644 | return err; | |
645 | } | |
646 | ||
647 | static void __exit exit_romfs_fs(void) | |
648 | { | |
649 | unregister_filesystem(&romfs_fs_type); | |
650 | destroy_inodecache(); | |
651 | } | |
652 | ||
653 | /* Yes, works even as a module... :) */ | |
654 | ||
655 | module_init(init_romfs_fs) | |
656 | module_exit(exit_romfs_fs) | |
657 | MODULE_LICENSE("GPL"); |