Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Compressed rom filesystem for Linux. | |
3 | * | |
4 | * Copyright (C) 1999 Linus Torvalds. | |
5 | * | |
6 | * This file is released under the GPL. | |
7 | */ | |
8 | ||
9 | /* | |
10 | * These are the VFS interfaces to the compressed rom filesystem. | |
11 | * The actual compression is based on zlib, see the other files. | |
12 | */ | |
13 | ||
14 | #include <linux/module.h> | |
15 | #include <linux/fs.h> | |
16 | #include <linux/pagemap.h> | |
17 | #include <linux/init.h> | |
18 | #include <linux/string.h> | |
19 | #include <linux/blkdev.h> | |
20 | #include <linux/cramfs_fs.h> | |
21 | #include <linux/slab.h> | |
22 | #include <linux/cramfs_fs_sb.h> | |
23 | #include <linux/buffer_head.h> | |
24 | #include <linux/vfs.h> | |
353ab6e9 | 25 | #include <linux/mutex.h> |
1da177e4 LT |
26 | |
27 | #include <asm/uaccess.h> | |
28 | ||
ee9b6d61 | 29 | static const struct super_operations cramfs_ops; |
754661f1 | 30 | static const struct inode_operations cramfs_dir_inode_operations; |
4b6f5d20 | 31 | static const struct file_operations cramfs_directory_operations; |
f5e54d6e | 32 | static const struct address_space_operations cramfs_aops; |
1da177e4 | 33 | |
353ab6e9 | 34 | static DEFINE_MUTEX(read_mutex); |
1da177e4 LT |
35 | |
36 | ||
6f772fe6 | 37 | /* These macros may change in future, to provide better st_ino semantics. */ |
1da177e4 LT |
38 | #define OFFSET(x) ((x)->i_ino) |
39 | ||
6f772fe6 | 40 | static unsigned long cramino(struct cramfs_inode *cino, unsigned int offset) |
a97c9bf3 | 41 | { |
6f772fe6 SS |
42 | if (!cino->offset) |
43 | return offset + 1; | |
44 | if (!cino->size) | |
45 | return offset + 1; | |
46 | ||
47 | /* | |
48 | * The file mode test fixes buggy mkcramfs implementations where | |
49 | * cramfs_inode->offset is set to a non zero value for entries | |
50 | * which did not contain data, like devices node and fifos. | |
51 | */ | |
52 | switch (cino->mode & S_IFMT) { | |
53 | case S_IFREG: | |
54 | case S_IFDIR: | |
55 | case S_IFLNK: | |
56 | return cino->offset << 2; | |
57 | default: | |
58 | break; | |
59 | } | |
60 | return offset + 1; | |
61 | } | |
62 | ||
63 | static struct inode *get_cramfs_inode(struct super_block *sb, | |
64 | struct cramfs_inode *cramfs_inode, unsigned int offset) | |
65 | { | |
66 | struct inode *inode; | |
77b8a75f | 67 | static struct timespec zerotime; |
6f772fe6 SS |
68 | |
69 | inode = iget_locked(sb, cramino(cramfs_inode, offset)); | |
70 | if (!inode) | |
71 | return ERR_PTR(-ENOMEM); | |
72 | if (!(inode->i_state & I_NEW)) | |
73 | return inode; | |
74 | ||
75 | switch (cramfs_inode->mode & S_IFMT) { | |
76 | case S_IFREG: | |
77 | inode->i_fop = &generic_ro_fops; | |
78 | inode->i_data.a_ops = &cramfs_aops; | |
79 | break; | |
80 | case S_IFDIR: | |
81 | inode->i_op = &cramfs_dir_inode_operations; | |
82 | inode->i_fop = &cramfs_directory_operations; | |
83 | break; | |
84 | case S_IFLNK: | |
85 | inode->i_op = &page_symlink_inode_operations; | |
86 | inode->i_data.a_ops = &cramfs_aops; | |
87 | break; | |
88 | default: | |
89 | init_special_inode(inode, cramfs_inode->mode, | |
90 | old_decode_dev(cramfs_inode->size)); | |
91 | } | |
92 | ||
77b8a75f AV |
93 | inode->i_mode = cramfs_inode->mode; |
94 | inode->i_uid = cramfs_inode->uid; | |
77b8a75f | 95 | inode->i_gid = cramfs_inode->gid; |
6f772fe6 SS |
96 | |
97 | /* if the lower 2 bits are zero, the inode contains data */ | |
98 | if (!(inode->i_ino & 3)) { | |
99 | inode->i_size = cramfs_inode->size; | |
100 | inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1; | |
101 | } | |
102 | ||
77b8a75f AV |
103 | /* Struct copy intentional */ |
104 | inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime; | |
105 | /* inode->i_nlink is left 1 - arguably wrong for directories, | |
106 | but it's the best we can do without reading the directory | |
107 | contents. 1 yields the right result in GNU find, even | |
108 | without -noleaf option. */ | |
a97c9bf3 | 109 | |
6f772fe6 SS |
110 | unlock_new_inode(inode); |
111 | ||
1da177e4 LT |
112 | return inode; |
113 | } | |
114 | ||
115 | /* | |
116 | * We have our own block cache: don't fill up the buffer cache | |
117 | * with the rom-image, because the way the filesystem is set | |
118 | * up the accesses should be fairly regular and cached in the | |
119 | * page cache and dentry tree anyway.. | |
120 | * | |
121 | * This also acts as a way to guarantee contiguous areas of up to | |
122 | * BLKS_PER_BUF*PAGE_CACHE_SIZE, so that the caller doesn't need to | |
123 | * worry about end-of-buffer issues even when decompressing a full | |
124 | * page cache. | |
125 | */ | |
126 | #define READ_BUFFERS (2) | |
127 | /* NEXT_BUFFER(): Loop over [0..(READ_BUFFERS-1)]. */ | |
128 | #define NEXT_BUFFER(_ix) ((_ix) ^ 1) | |
129 | ||
130 | /* | |
131 | * BLKS_PER_BUF_SHIFT should be at least 2 to allow for "compressed" | |
132 | * data that takes up more space than the original and with unlucky | |
133 | * alignment. | |
134 | */ | |
135 | #define BLKS_PER_BUF_SHIFT (2) | |
136 | #define BLKS_PER_BUF (1 << BLKS_PER_BUF_SHIFT) | |
137 | #define BUFFER_SIZE (BLKS_PER_BUF*PAGE_CACHE_SIZE) | |
138 | ||
139 | static unsigned char read_buffers[READ_BUFFERS][BUFFER_SIZE]; | |
140 | static unsigned buffer_blocknr[READ_BUFFERS]; | |
141 | static struct super_block * buffer_dev[READ_BUFFERS]; | |
142 | static int next_buffer; | |
143 | ||
144 | /* | |
145 | * Returns a pointer to a buffer containing at least LEN bytes of | |
146 | * filesystem starting at byte offset OFFSET into the filesystem. | |
147 | */ | |
148 | static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned int len) | |
149 | { | |
150 | struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping; | |
151 | struct page *pages[BLKS_PER_BUF]; | |
6bbfb077 | 152 | unsigned i, blocknr, buffer; |
1da177e4 LT |
153 | unsigned long devsize; |
154 | char *data; | |
155 | ||
156 | if (!len) | |
157 | return NULL; | |
158 | blocknr = offset >> PAGE_CACHE_SHIFT; | |
159 | offset &= PAGE_CACHE_SIZE - 1; | |
160 | ||
161 | /* Check if an existing buffer already has the data.. */ | |
162 | for (i = 0; i < READ_BUFFERS; i++) { | |
163 | unsigned int blk_offset; | |
164 | ||
165 | if (buffer_dev[i] != sb) | |
166 | continue; | |
167 | if (blocknr < buffer_blocknr[i]) | |
168 | continue; | |
169 | blk_offset = (blocknr - buffer_blocknr[i]) << PAGE_CACHE_SHIFT; | |
170 | blk_offset += offset; | |
171 | if (blk_offset + len > BUFFER_SIZE) | |
172 | continue; | |
173 | return read_buffers[i] + blk_offset; | |
174 | } | |
175 | ||
176 | devsize = mapping->host->i_size >> PAGE_CACHE_SHIFT; | |
177 | ||
178 | /* Ok, read in BLKS_PER_BUF pages completely first. */ | |
1da177e4 LT |
179 | for (i = 0; i < BLKS_PER_BUF; i++) { |
180 | struct page *page = NULL; | |
181 | ||
182 | if (blocknr + i < devsize) { | |
6fe6900e NP |
183 | page = read_mapping_page_async(mapping, blocknr + i, |
184 | NULL); | |
1da177e4 LT |
185 | /* synchronous error? */ |
186 | if (IS_ERR(page)) | |
187 | page = NULL; | |
188 | } | |
189 | pages[i] = page; | |
190 | } | |
191 | ||
192 | for (i = 0; i < BLKS_PER_BUF; i++) { | |
193 | struct page *page = pages[i]; | |
194 | if (page) { | |
195 | wait_on_page_locked(page); | |
196 | if (!PageUptodate(page)) { | |
197 | /* asynchronous error */ | |
198 | page_cache_release(page); | |
199 | pages[i] = NULL; | |
200 | } | |
201 | } | |
202 | } | |
203 | ||
204 | buffer = next_buffer; | |
205 | next_buffer = NEXT_BUFFER(buffer); | |
206 | buffer_blocknr[buffer] = blocknr; | |
207 | buffer_dev[buffer] = sb; | |
208 | ||
209 | data = read_buffers[buffer]; | |
210 | for (i = 0; i < BLKS_PER_BUF; i++) { | |
211 | struct page *page = pages[i]; | |
212 | if (page) { | |
213 | memcpy(data, kmap(page), PAGE_CACHE_SIZE); | |
214 | kunmap(page); | |
215 | page_cache_release(page); | |
216 | } else | |
217 | memset(data, 0, PAGE_CACHE_SIZE); | |
218 | data += PAGE_CACHE_SIZE; | |
219 | } | |
220 | return read_buffers[buffer] + offset; | |
221 | } | |
222 | ||
223 | static void cramfs_put_super(struct super_block *sb) | |
224 | { | |
225 | kfree(sb->s_fs_info); | |
226 | sb->s_fs_info = NULL; | |
227 | } | |
228 | ||
229 | static int cramfs_remount(struct super_block *sb, int *flags, char *data) | |
230 | { | |
231 | *flags |= MS_RDONLY; | |
232 | return 0; | |
233 | } | |
234 | ||
235 | static int cramfs_fill_super(struct super_block *sb, void *data, int silent) | |
236 | { | |
237 | int i; | |
238 | struct cramfs_super super; | |
239 | unsigned long root_offset; | |
240 | struct cramfs_sb_info *sbi; | |
241 | struct inode *root; | |
242 | ||
243 | sb->s_flags |= MS_RDONLY; | |
244 | ||
f8314dc6 | 245 | sbi = kzalloc(sizeof(struct cramfs_sb_info), GFP_KERNEL); |
1da177e4 LT |
246 | if (!sbi) |
247 | return -ENOMEM; | |
248 | sb->s_fs_info = sbi; | |
1da177e4 LT |
249 | |
250 | /* Invalidate the read buffers on mount: think disk change.. */ | |
353ab6e9 | 251 | mutex_lock(&read_mutex); |
1da177e4 LT |
252 | for (i = 0; i < READ_BUFFERS; i++) |
253 | buffer_blocknr[i] = -1; | |
254 | ||
255 | /* Read the first block and get the superblock from it */ | |
256 | memcpy(&super, cramfs_read(sb, 0, sizeof(super)), sizeof(super)); | |
353ab6e9 | 257 | mutex_unlock(&read_mutex); |
1da177e4 LT |
258 | |
259 | /* Do sanity checks on the superblock */ | |
260 | if (super.magic != CRAMFS_MAGIC) { | |
ac8d35c5 AD |
261 | /* check for wrong endianess */ |
262 | if (super.magic == CRAMFS_MAGIC_WEND) { | |
263 | if (!silent) | |
264 | printk(KERN_ERR "cramfs: wrong endianess\n"); | |
265 | goto out; | |
266 | } | |
267 | ||
1da177e4 | 268 | /* check at 512 byte offset */ |
353ab6e9 | 269 | mutex_lock(&read_mutex); |
1da177e4 | 270 | memcpy(&super, cramfs_read(sb, 512, sizeof(super)), sizeof(super)); |
353ab6e9 | 271 | mutex_unlock(&read_mutex); |
1da177e4 | 272 | if (super.magic != CRAMFS_MAGIC) { |
ac8d35c5 AD |
273 | if (super.magic == CRAMFS_MAGIC_WEND && !silent) |
274 | printk(KERN_ERR "cramfs: wrong endianess\n"); | |
275 | else if (!silent) | |
1da177e4 LT |
276 | printk(KERN_ERR "cramfs: wrong magic\n"); |
277 | goto out; | |
278 | } | |
279 | } | |
280 | ||
281 | /* get feature flags first */ | |
282 | if (super.flags & ~CRAMFS_SUPPORTED_FLAGS) { | |
283 | printk(KERN_ERR "cramfs: unsupported filesystem features\n"); | |
284 | goto out; | |
285 | } | |
286 | ||
287 | /* Check that the root inode is in a sane state */ | |
288 | if (!S_ISDIR(super.root.mode)) { | |
289 | printk(KERN_ERR "cramfs: root is not a directory\n"); | |
290 | goto out; | |
291 | } | |
6f772fe6 SS |
292 | /* correct strange, hard-coded permissions of mkcramfs */ |
293 | super.root.mode |= (S_IRUSR | S_IXUSR | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH); | |
294 | ||
1da177e4 LT |
295 | root_offset = super.root.offset << 2; |
296 | if (super.flags & CRAMFS_FLAG_FSID_VERSION_2) { | |
297 | sbi->size=super.size; | |
298 | sbi->blocks=super.fsid.blocks; | |
299 | sbi->files=super.fsid.files; | |
300 | } else { | |
301 | sbi->size=1<<28; | |
302 | sbi->blocks=0; | |
303 | sbi->files=0; | |
304 | } | |
305 | sbi->magic=super.magic; | |
306 | sbi->flags=super.flags; | |
307 | if (root_offset == 0) | |
308 | printk(KERN_INFO "cramfs: empty filesystem"); | |
309 | else if (!(super.flags & CRAMFS_FLAG_SHIFTED_ROOT_OFFSET) && | |
310 | ((root_offset != sizeof(struct cramfs_super)) && | |
311 | (root_offset != 512 + sizeof(struct cramfs_super)))) | |
312 | { | |
313 | printk(KERN_ERR "cramfs: bad root offset %lu\n", root_offset); | |
314 | goto out; | |
315 | } | |
316 | ||
317 | /* Set it all up.. */ | |
318 | sb->s_op = &cramfs_ops; | |
6f772fe6 | 319 | root = get_cramfs_inode(sb, &super.root, 0); |
1da177e4 LT |
320 | if (!root) |
321 | goto out; | |
322 | sb->s_root = d_alloc_root(root); | |
323 | if (!sb->s_root) { | |
324 | iput(root); | |
325 | goto out; | |
326 | } | |
327 | return 0; | |
328 | out: | |
329 | kfree(sbi); | |
330 | sb->s_fs_info = NULL; | |
331 | return -EINVAL; | |
332 | } | |
333 | ||
726c3342 | 334 | static int cramfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 | 335 | { |
726c3342 | 336 | struct super_block *sb = dentry->d_sb; |
94ea77ac | 337 | u64 id = huge_encode_dev(sb->s_bdev->bd_dev); |
726c3342 | 338 | |
1da177e4 LT |
339 | buf->f_type = CRAMFS_MAGIC; |
340 | buf->f_bsize = PAGE_CACHE_SIZE; | |
341 | buf->f_blocks = CRAMFS_SB(sb)->blocks; | |
342 | buf->f_bfree = 0; | |
343 | buf->f_bavail = 0; | |
344 | buf->f_files = CRAMFS_SB(sb)->files; | |
345 | buf->f_ffree = 0; | |
94ea77ac CL |
346 | buf->f_fsid.val[0] = (u32)id; |
347 | buf->f_fsid.val[1] = (u32)(id >> 32); | |
1da177e4 LT |
348 | buf->f_namelen = CRAMFS_MAXPATHLEN; |
349 | return 0; | |
350 | } | |
351 | ||
352 | /* | |
353 | * Read a cramfs directory entry. | |
354 | */ | |
355 | static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir) | |
356 | { | |
352d8af7 | 357 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
358 | struct super_block *sb = inode->i_sb; |
359 | char *buf; | |
360 | unsigned int offset; | |
361 | int copied; | |
362 | ||
363 | /* Offset within the thing. */ | |
364 | offset = filp->f_pos; | |
365 | if (offset >= inode->i_size) | |
366 | return 0; | |
367 | /* Directory entries are always 4-byte aligned */ | |
368 | if (offset & 3) | |
369 | return -EINVAL; | |
370 | ||
4176ed59 | 371 | buf = kmalloc(CRAMFS_MAXPATHLEN, GFP_KERNEL); |
1da177e4 LT |
372 | if (!buf) |
373 | return -ENOMEM; | |
374 | ||
375 | copied = 0; | |
376 | while (offset < inode->i_size) { | |
377 | struct cramfs_inode *de; | |
378 | unsigned long nextoffset; | |
379 | char *name; | |
380 | ino_t ino; | |
381 | mode_t mode; | |
382 | int namelen, error; | |
383 | ||
353ab6e9 | 384 | mutex_lock(&read_mutex); |
4176ed59 | 385 | de = cramfs_read(sb, OFFSET(inode) + offset, sizeof(*de)+CRAMFS_MAXPATHLEN); |
1da177e4 LT |
386 | name = (char *)(de+1); |
387 | ||
388 | /* | |
389 | * Namelengths on disk are shifted by two | |
390 | * and the name padded out to 4-byte boundaries | |
391 | * with zeroes. | |
392 | */ | |
393 | namelen = de->namelen << 2; | |
394 | memcpy(buf, name, namelen); | |
6f772fe6 | 395 | ino = cramino(de, OFFSET(inode) + offset); |
1da177e4 | 396 | mode = de->mode; |
353ab6e9 | 397 | mutex_unlock(&read_mutex); |
1da177e4 LT |
398 | nextoffset = offset + sizeof(*de) + namelen; |
399 | for (;;) { | |
400 | if (!namelen) { | |
401 | kfree(buf); | |
402 | return -EIO; | |
403 | } | |
404 | if (buf[namelen-1]) | |
405 | break; | |
406 | namelen--; | |
407 | } | |
408 | error = filldir(dirent, buf, namelen, offset, ino, mode >> 12); | |
409 | if (error) | |
410 | break; | |
411 | ||
412 | offset = nextoffset; | |
413 | filp->f_pos = offset; | |
414 | copied++; | |
415 | } | |
416 | kfree(buf); | |
417 | return 0; | |
418 | } | |
419 | ||
420 | /* | |
421 | * Lookup and fill in the inode data.. | |
422 | */ | |
423 | static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) | |
424 | { | |
425 | unsigned int offset = 0; | |
426 | int sorted; | |
427 | ||
353ab6e9 | 428 | mutex_lock(&read_mutex); |
1da177e4 LT |
429 | sorted = CRAMFS_SB(dir->i_sb)->flags & CRAMFS_FLAG_SORTED_DIRS; |
430 | while (offset < dir->i_size) { | |
431 | struct cramfs_inode *de; | |
432 | char *name; | |
433 | int namelen, retval; | |
6f772fe6 | 434 | int dir_off = OFFSET(dir) + offset; |
1da177e4 | 435 | |
6f772fe6 | 436 | de = cramfs_read(dir->i_sb, dir_off, sizeof(*de)+CRAMFS_MAXPATHLEN); |
1da177e4 LT |
437 | name = (char *)(de+1); |
438 | ||
439 | /* Try to take advantage of sorted directories */ | |
440 | if (sorted && (dentry->d_name.name[0] < name[0])) | |
441 | break; | |
442 | ||
443 | namelen = de->namelen << 2; | |
444 | offset += sizeof(*de) + namelen; | |
445 | ||
446 | /* Quick check that the name is roughly the right length */ | |
447 | if (((dentry->d_name.len + 3) & ~3) != namelen) | |
448 | continue; | |
449 | ||
450 | for (;;) { | |
451 | if (!namelen) { | |
353ab6e9 | 452 | mutex_unlock(&read_mutex); |
1da177e4 LT |
453 | return ERR_PTR(-EIO); |
454 | } | |
455 | if (name[namelen-1]) | |
456 | break; | |
457 | namelen--; | |
458 | } | |
459 | if (namelen != dentry->d_name.len) | |
460 | continue; | |
461 | retval = memcmp(dentry->d_name.name, name, namelen); | |
462 | if (retval > 0) | |
463 | continue; | |
464 | if (!retval) { | |
465 | struct cramfs_inode entry = *de; | |
353ab6e9 | 466 | mutex_unlock(&read_mutex); |
6f772fe6 | 467 | d_add(dentry, get_cramfs_inode(dir->i_sb, &entry, dir_off)); |
1da177e4 LT |
468 | return NULL; |
469 | } | |
470 | /* else (retval < 0) */ | |
471 | if (sorted) | |
472 | break; | |
473 | } | |
353ab6e9 | 474 | mutex_unlock(&read_mutex); |
1da177e4 LT |
475 | d_add(dentry, NULL); |
476 | return NULL; | |
477 | } | |
478 | ||
479 | static int cramfs_readpage(struct file *file, struct page * page) | |
480 | { | |
481 | struct inode *inode = page->mapping->host; | |
98310e58 DV |
482 | u32 maxblock; |
483 | int bytes_filled; | |
1da177e4 LT |
484 | void *pgdata; |
485 | ||
486 | maxblock = (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; | |
487 | bytes_filled = 0; | |
98310e58 DV |
488 | pgdata = kmap(page); |
489 | ||
1da177e4 LT |
490 | if (page->index < maxblock) { |
491 | struct super_block *sb = inode->i_sb; | |
492 | u32 blkptr_offset = OFFSET(inode) + page->index*4; | |
493 | u32 start_offset, compr_len; | |
494 | ||
495 | start_offset = OFFSET(inode) + maxblock*4; | |
353ab6e9 | 496 | mutex_lock(&read_mutex); |
1da177e4 | 497 | if (page->index) |
98310e58 DV |
498 | start_offset = *(u32 *) cramfs_read(sb, blkptr_offset-4, |
499 | 4); | |
500 | compr_len = (*(u32 *) cramfs_read(sb, blkptr_offset, 4) - | |
501 | start_offset); | |
353ab6e9 | 502 | mutex_unlock(&read_mutex); |
98310e58 | 503 | |
1da177e4 LT |
504 | if (compr_len == 0) |
505 | ; /* hole */ | |
98310e58 DV |
506 | else if (unlikely(compr_len > (PAGE_CACHE_SIZE << 1))) { |
507 | pr_err("cramfs: bad compressed blocksize %u\n", | |
508 | compr_len); | |
509 | goto err; | |
510 | } else { | |
353ab6e9 | 511 | mutex_lock(&read_mutex); |
1da177e4 LT |
512 | bytes_filled = cramfs_uncompress_block(pgdata, |
513 | PAGE_CACHE_SIZE, | |
514 | cramfs_read(sb, start_offset, compr_len), | |
515 | compr_len); | |
353ab6e9 | 516 | mutex_unlock(&read_mutex); |
98310e58 DV |
517 | if (unlikely(bytes_filled < 0)) |
518 | goto err; | |
1da177e4 | 519 | } |
98310e58 DV |
520 | } |
521 | ||
1da177e4 | 522 | memset(pgdata + bytes_filled, 0, PAGE_CACHE_SIZE - bytes_filled); |
1da177e4 | 523 | flush_dcache_page(page); |
98310e58 | 524 | kunmap(page); |
1da177e4 LT |
525 | SetPageUptodate(page); |
526 | unlock_page(page); | |
527 | return 0; | |
98310e58 DV |
528 | |
529 | err: | |
530 | kunmap(page); | |
531 | ClearPageUptodate(page); | |
532 | SetPageError(page); | |
533 | unlock_page(page); | |
534 | return 0; | |
1da177e4 LT |
535 | } |
536 | ||
f5e54d6e | 537 | static const struct address_space_operations cramfs_aops = { |
1da177e4 LT |
538 | .readpage = cramfs_readpage |
539 | }; | |
540 | ||
541 | /* | |
542 | * Our operations: | |
543 | */ | |
544 | ||
545 | /* | |
546 | * A directory can only readdir | |
547 | */ | |
4b6f5d20 | 548 | static const struct file_operations cramfs_directory_operations = { |
1da177e4 LT |
549 | .llseek = generic_file_llseek, |
550 | .read = generic_read_dir, | |
551 | .readdir = cramfs_readdir, | |
552 | }; | |
553 | ||
754661f1 | 554 | static const struct inode_operations cramfs_dir_inode_operations = { |
1da177e4 LT |
555 | .lookup = cramfs_lookup, |
556 | }; | |
557 | ||
ee9b6d61 | 558 | static const struct super_operations cramfs_ops = { |
1da177e4 LT |
559 | .put_super = cramfs_put_super, |
560 | .remount_fs = cramfs_remount, | |
561 | .statfs = cramfs_statfs, | |
562 | }; | |
563 | ||
152a0836 AV |
564 | static struct dentry *cramfs_mount(struct file_system_type *fs_type, |
565 | int flags, const char *dev_name, void *data) | |
1da177e4 | 566 | { |
152a0836 | 567 | return mount_bdev(fs_type, flags, dev_name, data, cramfs_fill_super); |
1da177e4 LT |
568 | } |
569 | ||
570 | static struct file_system_type cramfs_fs_type = { | |
571 | .owner = THIS_MODULE, | |
572 | .name = "cramfs", | |
152a0836 | 573 | .mount = cramfs_mount, |
1da177e4 LT |
574 | .kill_sb = kill_block_super, |
575 | .fs_flags = FS_REQUIRES_DEV, | |
576 | }; | |
577 | ||
578 | static int __init init_cramfs_fs(void) | |
579 | { | |
50d44ed0 AD |
580 | int rv; |
581 | ||
582 | rv = cramfs_uncompress_init(); | |
583 | if (rv < 0) | |
584 | return rv; | |
585 | rv = register_filesystem(&cramfs_fs_type); | |
586 | if (rv < 0) | |
587 | cramfs_uncompress_exit(); | |
588 | return rv; | |
1da177e4 LT |
589 | } |
590 | ||
591 | static void __exit exit_cramfs_fs(void) | |
592 | { | |
593 | cramfs_uncompress_exit(); | |
594 | unregister_filesystem(&cramfs_fs_type); | |
595 | } | |
596 | ||
597 | module_init(init_cramfs_fs) | |
598 | module_exit(exit_cramfs_fs) | |
599 | MODULE_LICENSE("GPL"); |