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 | ||
37 | /* These two macros may change in future, to provide better st_ino | |
38 | semantics. */ | |
ff3aea0e | 39 | #define CRAMINO(x) (((x)->offset && (x)->size)?(x)->offset<<2:1) |
1da177e4 LT |
40 | #define OFFSET(x) ((x)->i_ino) |
41 | ||
a97c9bf3 DJ |
42 | |
43 | static int cramfs_iget5_test(struct inode *inode, void *opaque) | |
44 | { | |
45 | struct cramfs_inode *cramfs_inode = opaque; | |
82d63fc9 | 46 | return inode->i_ino == CRAMINO(cramfs_inode) && inode->i_ino != 1; |
a97c9bf3 DJ |
47 | } |
48 | ||
49 | static int cramfs_iget5_set(struct inode *inode, void *opaque) | |
50 | { | |
51 | struct cramfs_inode *cramfs_inode = opaque; | |
52 | inode->i_ino = CRAMINO(cramfs_inode); | |
53 | return 0; | |
54 | } | |
55 | ||
56 | static struct inode *get_cramfs_inode(struct super_block *sb, | |
57 | struct cramfs_inode * cramfs_inode) | |
1da177e4 | 58 | { |
a97c9bf3 DJ |
59 | struct inode *inode = iget5_locked(sb, CRAMINO(cramfs_inode), |
60 | cramfs_iget5_test, cramfs_iget5_set, | |
61 | cramfs_inode); | |
82d63fc9 AV |
62 | static struct timespec zerotime; |
63 | ||
a97c9bf3 | 64 | if (inode && (inode->i_state & I_NEW)) { |
82d63fc9 AV |
65 | inode->i_mode = cramfs_inode->mode; |
66 | inode->i_uid = cramfs_inode->uid; | |
67 | inode->i_size = cramfs_inode->size; | |
68 | inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1; | |
69 | inode->i_gid = cramfs_inode->gid; | |
70 | /* Struct copy intentional */ | |
71 | inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime; | |
72 | /* inode->i_nlink is left 1 - arguably wrong for directories, | |
73 | but it's the best we can do without reading the directory | |
74 | contents. 1 yields the right result in GNU find, even | |
75 | without -noleaf option. */ | |
76 | if (S_ISREG(inode->i_mode)) { | |
77 | inode->i_fop = &generic_ro_fops; | |
78 | inode->i_data.a_ops = &cramfs_aops; | |
79 | } else if (S_ISDIR(inode->i_mode)) { | |
80 | inode->i_op = &cramfs_dir_inode_operations; | |
81 | inode->i_fop = &cramfs_directory_operations; | |
82 | } else if (S_ISLNK(inode->i_mode)) { | |
83 | inode->i_op = &page_symlink_inode_operations; | |
84 | inode->i_data.a_ops = &cramfs_aops; | |
85 | } else { | |
82d63fc9 AV |
86 | init_special_inode(inode, inode->i_mode, |
87 | old_decode_dev(cramfs_inode->size)); | |
88 | } | |
a97c9bf3 | 89 | unlock_new_inode(inode); |
1da177e4 LT |
90 | } |
91 | return inode; | |
92 | } | |
93 | ||
82d63fc9 AV |
94 | static void cramfs_drop_inode(struct inode *inode) |
95 | { | |
96 | if (inode->i_ino == 1) | |
97 | generic_delete_inode(inode); | |
98 | else | |
99 | generic_drop_inode(inode); | |
100 | } | |
101 | ||
1da177e4 LT |
102 | /* |
103 | * We have our own block cache: don't fill up the buffer cache | |
104 | * with the rom-image, because the way the filesystem is set | |
105 | * up the accesses should be fairly regular and cached in the | |
106 | * page cache and dentry tree anyway.. | |
107 | * | |
108 | * This also acts as a way to guarantee contiguous areas of up to | |
109 | * BLKS_PER_BUF*PAGE_CACHE_SIZE, so that the caller doesn't need to | |
110 | * worry about end-of-buffer issues even when decompressing a full | |
111 | * page cache. | |
112 | */ | |
113 | #define READ_BUFFERS (2) | |
114 | /* NEXT_BUFFER(): Loop over [0..(READ_BUFFERS-1)]. */ | |
115 | #define NEXT_BUFFER(_ix) ((_ix) ^ 1) | |
116 | ||
117 | /* | |
118 | * BLKS_PER_BUF_SHIFT should be at least 2 to allow for "compressed" | |
119 | * data that takes up more space than the original and with unlucky | |
120 | * alignment. | |
121 | */ | |
122 | #define BLKS_PER_BUF_SHIFT (2) | |
123 | #define BLKS_PER_BUF (1 << BLKS_PER_BUF_SHIFT) | |
124 | #define BUFFER_SIZE (BLKS_PER_BUF*PAGE_CACHE_SIZE) | |
125 | ||
126 | static unsigned char read_buffers[READ_BUFFERS][BUFFER_SIZE]; | |
127 | static unsigned buffer_blocknr[READ_BUFFERS]; | |
128 | static struct super_block * buffer_dev[READ_BUFFERS]; | |
129 | static int next_buffer; | |
130 | ||
131 | /* | |
132 | * Returns a pointer to a buffer containing at least LEN bytes of | |
133 | * filesystem starting at byte offset OFFSET into the filesystem. | |
134 | */ | |
135 | static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned int len) | |
136 | { | |
137 | struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping; | |
138 | struct page *pages[BLKS_PER_BUF]; | |
6bbfb077 | 139 | unsigned i, blocknr, buffer; |
1da177e4 LT |
140 | unsigned long devsize; |
141 | char *data; | |
142 | ||
143 | if (!len) | |
144 | return NULL; | |
145 | blocknr = offset >> PAGE_CACHE_SHIFT; | |
146 | offset &= PAGE_CACHE_SIZE - 1; | |
147 | ||
148 | /* Check if an existing buffer already has the data.. */ | |
149 | for (i = 0; i < READ_BUFFERS; i++) { | |
150 | unsigned int blk_offset; | |
151 | ||
152 | if (buffer_dev[i] != sb) | |
153 | continue; | |
154 | if (blocknr < buffer_blocknr[i]) | |
155 | continue; | |
156 | blk_offset = (blocknr - buffer_blocknr[i]) << PAGE_CACHE_SHIFT; | |
157 | blk_offset += offset; | |
158 | if (blk_offset + len > BUFFER_SIZE) | |
159 | continue; | |
160 | return read_buffers[i] + blk_offset; | |
161 | } | |
162 | ||
163 | devsize = mapping->host->i_size >> PAGE_CACHE_SHIFT; | |
164 | ||
165 | /* Ok, read in BLKS_PER_BUF pages completely first. */ | |
1da177e4 LT |
166 | for (i = 0; i < BLKS_PER_BUF; i++) { |
167 | struct page *page = NULL; | |
168 | ||
169 | if (blocknr + i < devsize) { | |
6fe6900e NP |
170 | page = read_mapping_page_async(mapping, blocknr + i, |
171 | NULL); | |
1da177e4 LT |
172 | /* synchronous error? */ |
173 | if (IS_ERR(page)) | |
174 | page = NULL; | |
175 | } | |
176 | pages[i] = page; | |
177 | } | |
178 | ||
179 | for (i = 0; i < BLKS_PER_BUF; i++) { | |
180 | struct page *page = pages[i]; | |
181 | if (page) { | |
182 | wait_on_page_locked(page); | |
183 | if (!PageUptodate(page)) { | |
184 | /* asynchronous error */ | |
185 | page_cache_release(page); | |
186 | pages[i] = NULL; | |
187 | } | |
188 | } | |
189 | } | |
190 | ||
191 | buffer = next_buffer; | |
192 | next_buffer = NEXT_BUFFER(buffer); | |
193 | buffer_blocknr[buffer] = blocknr; | |
194 | buffer_dev[buffer] = sb; | |
195 | ||
196 | data = read_buffers[buffer]; | |
197 | for (i = 0; i < BLKS_PER_BUF; i++) { | |
198 | struct page *page = pages[i]; | |
199 | if (page) { | |
200 | memcpy(data, kmap(page), PAGE_CACHE_SIZE); | |
201 | kunmap(page); | |
202 | page_cache_release(page); | |
203 | } else | |
204 | memset(data, 0, PAGE_CACHE_SIZE); | |
205 | data += PAGE_CACHE_SIZE; | |
206 | } | |
207 | return read_buffers[buffer] + offset; | |
208 | } | |
209 | ||
210 | static void cramfs_put_super(struct super_block *sb) | |
211 | { | |
212 | kfree(sb->s_fs_info); | |
213 | sb->s_fs_info = NULL; | |
214 | } | |
215 | ||
216 | static int cramfs_remount(struct super_block *sb, int *flags, char *data) | |
217 | { | |
218 | *flags |= MS_RDONLY; | |
219 | return 0; | |
220 | } | |
221 | ||
222 | static int cramfs_fill_super(struct super_block *sb, void *data, int silent) | |
223 | { | |
224 | int i; | |
225 | struct cramfs_super super; | |
226 | unsigned long root_offset; | |
227 | struct cramfs_sb_info *sbi; | |
228 | struct inode *root; | |
229 | ||
230 | sb->s_flags |= MS_RDONLY; | |
231 | ||
f8314dc6 | 232 | sbi = kzalloc(sizeof(struct cramfs_sb_info), GFP_KERNEL); |
1da177e4 LT |
233 | if (!sbi) |
234 | return -ENOMEM; | |
235 | sb->s_fs_info = sbi; | |
1da177e4 LT |
236 | |
237 | /* Invalidate the read buffers on mount: think disk change.. */ | |
353ab6e9 | 238 | mutex_lock(&read_mutex); |
1da177e4 LT |
239 | for (i = 0; i < READ_BUFFERS; i++) |
240 | buffer_blocknr[i] = -1; | |
241 | ||
242 | /* Read the first block and get the superblock from it */ | |
243 | memcpy(&super, cramfs_read(sb, 0, sizeof(super)), sizeof(super)); | |
353ab6e9 | 244 | mutex_unlock(&read_mutex); |
1da177e4 LT |
245 | |
246 | /* Do sanity checks on the superblock */ | |
247 | if (super.magic != CRAMFS_MAGIC) { | |
ac8d35c5 AD |
248 | /* check for wrong endianess */ |
249 | if (super.magic == CRAMFS_MAGIC_WEND) { | |
250 | if (!silent) | |
251 | printk(KERN_ERR "cramfs: wrong endianess\n"); | |
252 | goto out; | |
253 | } | |
254 | ||
1da177e4 | 255 | /* check at 512 byte offset */ |
353ab6e9 | 256 | mutex_lock(&read_mutex); |
1da177e4 | 257 | memcpy(&super, cramfs_read(sb, 512, sizeof(super)), sizeof(super)); |
353ab6e9 | 258 | mutex_unlock(&read_mutex); |
1da177e4 | 259 | if (super.magic != CRAMFS_MAGIC) { |
ac8d35c5 AD |
260 | if (super.magic == CRAMFS_MAGIC_WEND && !silent) |
261 | printk(KERN_ERR "cramfs: wrong endianess\n"); | |
262 | else if (!silent) | |
1da177e4 LT |
263 | printk(KERN_ERR "cramfs: wrong magic\n"); |
264 | goto out; | |
265 | } | |
266 | } | |
267 | ||
268 | /* get feature flags first */ | |
269 | if (super.flags & ~CRAMFS_SUPPORTED_FLAGS) { | |
270 | printk(KERN_ERR "cramfs: unsupported filesystem features\n"); | |
271 | goto out; | |
272 | } | |
273 | ||
274 | /* Check that the root inode is in a sane state */ | |
275 | if (!S_ISDIR(super.root.mode)) { | |
276 | printk(KERN_ERR "cramfs: root is not a directory\n"); | |
277 | goto out; | |
278 | } | |
279 | root_offset = super.root.offset << 2; | |
280 | if (super.flags & CRAMFS_FLAG_FSID_VERSION_2) { | |
281 | sbi->size=super.size; | |
282 | sbi->blocks=super.fsid.blocks; | |
283 | sbi->files=super.fsid.files; | |
284 | } else { | |
285 | sbi->size=1<<28; | |
286 | sbi->blocks=0; | |
287 | sbi->files=0; | |
288 | } | |
289 | sbi->magic=super.magic; | |
290 | sbi->flags=super.flags; | |
291 | if (root_offset == 0) | |
292 | printk(KERN_INFO "cramfs: empty filesystem"); | |
293 | else if (!(super.flags & CRAMFS_FLAG_SHIFTED_ROOT_OFFSET) && | |
294 | ((root_offset != sizeof(struct cramfs_super)) && | |
295 | (root_offset != 512 + sizeof(struct cramfs_super)))) | |
296 | { | |
297 | printk(KERN_ERR "cramfs: bad root offset %lu\n", root_offset); | |
298 | goto out; | |
299 | } | |
300 | ||
301 | /* Set it all up.. */ | |
302 | sb->s_op = &cramfs_ops; | |
303 | root = get_cramfs_inode(sb, &super.root); | |
304 | if (!root) | |
305 | goto out; | |
306 | sb->s_root = d_alloc_root(root); | |
307 | if (!sb->s_root) { | |
308 | iput(root); | |
309 | goto out; | |
310 | } | |
311 | return 0; | |
312 | out: | |
313 | kfree(sbi); | |
314 | sb->s_fs_info = NULL; | |
315 | return -EINVAL; | |
316 | } | |
317 | ||
726c3342 | 318 | static int cramfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 | 319 | { |
726c3342 | 320 | struct super_block *sb = dentry->d_sb; |
94ea77ac | 321 | u64 id = huge_encode_dev(sb->s_bdev->bd_dev); |
726c3342 | 322 | |
1da177e4 LT |
323 | buf->f_type = CRAMFS_MAGIC; |
324 | buf->f_bsize = PAGE_CACHE_SIZE; | |
325 | buf->f_blocks = CRAMFS_SB(sb)->blocks; | |
326 | buf->f_bfree = 0; | |
327 | buf->f_bavail = 0; | |
328 | buf->f_files = CRAMFS_SB(sb)->files; | |
329 | buf->f_ffree = 0; | |
94ea77ac CL |
330 | buf->f_fsid.val[0] = (u32)id; |
331 | buf->f_fsid.val[1] = (u32)(id >> 32); | |
1da177e4 LT |
332 | buf->f_namelen = CRAMFS_MAXPATHLEN; |
333 | return 0; | |
334 | } | |
335 | ||
336 | /* | |
337 | * Read a cramfs directory entry. | |
338 | */ | |
339 | static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir) | |
340 | { | |
352d8af7 | 341 | struct inode *inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
342 | struct super_block *sb = inode->i_sb; |
343 | char *buf; | |
344 | unsigned int offset; | |
345 | int copied; | |
346 | ||
347 | /* Offset within the thing. */ | |
348 | offset = filp->f_pos; | |
349 | if (offset >= inode->i_size) | |
350 | return 0; | |
351 | /* Directory entries are always 4-byte aligned */ | |
352 | if (offset & 3) | |
353 | return -EINVAL; | |
354 | ||
4176ed59 | 355 | buf = kmalloc(CRAMFS_MAXPATHLEN, GFP_KERNEL); |
1da177e4 LT |
356 | if (!buf) |
357 | return -ENOMEM; | |
358 | ||
359 | copied = 0; | |
360 | while (offset < inode->i_size) { | |
361 | struct cramfs_inode *de; | |
362 | unsigned long nextoffset; | |
363 | char *name; | |
364 | ino_t ino; | |
365 | mode_t mode; | |
366 | int namelen, error; | |
367 | ||
353ab6e9 | 368 | mutex_lock(&read_mutex); |
4176ed59 | 369 | de = cramfs_read(sb, OFFSET(inode) + offset, sizeof(*de)+CRAMFS_MAXPATHLEN); |
1da177e4 LT |
370 | name = (char *)(de+1); |
371 | ||
372 | /* | |
373 | * Namelengths on disk are shifted by two | |
374 | * and the name padded out to 4-byte boundaries | |
375 | * with zeroes. | |
376 | */ | |
377 | namelen = de->namelen << 2; | |
378 | memcpy(buf, name, namelen); | |
379 | ino = CRAMINO(de); | |
380 | mode = de->mode; | |
353ab6e9 | 381 | mutex_unlock(&read_mutex); |
1da177e4 LT |
382 | nextoffset = offset + sizeof(*de) + namelen; |
383 | for (;;) { | |
384 | if (!namelen) { | |
385 | kfree(buf); | |
386 | return -EIO; | |
387 | } | |
388 | if (buf[namelen-1]) | |
389 | break; | |
390 | namelen--; | |
391 | } | |
392 | error = filldir(dirent, buf, namelen, offset, ino, mode >> 12); | |
393 | if (error) | |
394 | break; | |
395 | ||
396 | offset = nextoffset; | |
397 | filp->f_pos = offset; | |
398 | copied++; | |
399 | } | |
400 | kfree(buf); | |
401 | return 0; | |
402 | } | |
403 | ||
404 | /* | |
405 | * Lookup and fill in the inode data.. | |
406 | */ | |
407 | static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) | |
408 | { | |
409 | unsigned int offset = 0; | |
410 | int sorted; | |
411 | ||
353ab6e9 | 412 | mutex_lock(&read_mutex); |
1da177e4 LT |
413 | sorted = CRAMFS_SB(dir->i_sb)->flags & CRAMFS_FLAG_SORTED_DIRS; |
414 | while (offset < dir->i_size) { | |
415 | struct cramfs_inode *de; | |
416 | char *name; | |
417 | int namelen, retval; | |
418 | ||
4176ed59 | 419 | de = cramfs_read(dir->i_sb, OFFSET(dir) + offset, sizeof(*de)+CRAMFS_MAXPATHLEN); |
1da177e4 LT |
420 | name = (char *)(de+1); |
421 | ||
422 | /* Try to take advantage of sorted directories */ | |
423 | if (sorted && (dentry->d_name.name[0] < name[0])) | |
424 | break; | |
425 | ||
426 | namelen = de->namelen << 2; | |
427 | offset += sizeof(*de) + namelen; | |
428 | ||
429 | /* Quick check that the name is roughly the right length */ | |
430 | if (((dentry->d_name.len + 3) & ~3) != namelen) | |
431 | continue; | |
432 | ||
433 | for (;;) { | |
434 | if (!namelen) { | |
353ab6e9 | 435 | mutex_unlock(&read_mutex); |
1da177e4 LT |
436 | return ERR_PTR(-EIO); |
437 | } | |
438 | if (name[namelen-1]) | |
439 | break; | |
440 | namelen--; | |
441 | } | |
442 | if (namelen != dentry->d_name.len) | |
443 | continue; | |
444 | retval = memcmp(dentry->d_name.name, name, namelen); | |
445 | if (retval > 0) | |
446 | continue; | |
447 | if (!retval) { | |
448 | struct cramfs_inode entry = *de; | |
353ab6e9 | 449 | mutex_unlock(&read_mutex); |
1da177e4 LT |
450 | d_add(dentry, get_cramfs_inode(dir->i_sb, &entry)); |
451 | return NULL; | |
452 | } | |
453 | /* else (retval < 0) */ | |
454 | if (sorted) | |
455 | break; | |
456 | } | |
353ab6e9 | 457 | mutex_unlock(&read_mutex); |
1da177e4 LT |
458 | d_add(dentry, NULL); |
459 | return NULL; | |
460 | } | |
461 | ||
462 | static int cramfs_readpage(struct file *file, struct page * page) | |
463 | { | |
464 | struct inode *inode = page->mapping->host; | |
98310e58 DV |
465 | u32 maxblock; |
466 | int bytes_filled; | |
1da177e4 LT |
467 | void *pgdata; |
468 | ||
469 | maxblock = (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; | |
470 | bytes_filled = 0; | |
98310e58 DV |
471 | pgdata = kmap(page); |
472 | ||
1da177e4 LT |
473 | if (page->index < maxblock) { |
474 | struct super_block *sb = inode->i_sb; | |
475 | u32 blkptr_offset = OFFSET(inode) + page->index*4; | |
476 | u32 start_offset, compr_len; | |
477 | ||
478 | start_offset = OFFSET(inode) + maxblock*4; | |
353ab6e9 | 479 | mutex_lock(&read_mutex); |
1da177e4 | 480 | if (page->index) |
98310e58 DV |
481 | start_offset = *(u32 *) cramfs_read(sb, blkptr_offset-4, |
482 | 4); | |
483 | compr_len = (*(u32 *) cramfs_read(sb, blkptr_offset, 4) - | |
484 | start_offset); | |
353ab6e9 | 485 | mutex_unlock(&read_mutex); |
98310e58 | 486 | |
1da177e4 LT |
487 | if (compr_len == 0) |
488 | ; /* hole */ | |
98310e58 DV |
489 | else if (unlikely(compr_len > (PAGE_CACHE_SIZE << 1))) { |
490 | pr_err("cramfs: bad compressed blocksize %u\n", | |
491 | compr_len); | |
492 | goto err; | |
493 | } else { | |
353ab6e9 | 494 | mutex_lock(&read_mutex); |
1da177e4 LT |
495 | bytes_filled = cramfs_uncompress_block(pgdata, |
496 | PAGE_CACHE_SIZE, | |
497 | cramfs_read(sb, start_offset, compr_len), | |
498 | compr_len); | |
353ab6e9 | 499 | mutex_unlock(&read_mutex); |
98310e58 DV |
500 | if (unlikely(bytes_filled < 0)) |
501 | goto err; | |
1da177e4 | 502 | } |
98310e58 DV |
503 | } |
504 | ||
1da177e4 | 505 | memset(pgdata + bytes_filled, 0, PAGE_CACHE_SIZE - bytes_filled); |
1da177e4 | 506 | flush_dcache_page(page); |
98310e58 | 507 | kunmap(page); |
1da177e4 LT |
508 | SetPageUptodate(page); |
509 | unlock_page(page); | |
510 | return 0; | |
98310e58 DV |
511 | |
512 | err: | |
513 | kunmap(page); | |
514 | ClearPageUptodate(page); | |
515 | SetPageError(page); | |
516 | unlock_page(page); | |
517 | return 0; | |
1da177e4 LT |
518 | } |
519 | ||
f5e54d6e | 520 | static const struct address_space_operations cramfs_aops = { |
1da177e4 LT |
521 | .readpage = cramfs_readpage |
522 | }; | |
523 | ||
524 | /* | |
525 | * Our operations: | |
526 | */ | |
527 | ||
528 | /* | |
529 | * A directory can only readdir | |
530 | */ | |
4b6f5d20 | 531 | static const struct file_operations cramfs_directory_operations = { |
1da177e4 LT |
532 | .llseek = generic_file_llseek, |
533 | .read = generic_read_dir, | |
534 | .readdir = cramfs_readdir, | |
535 | }; | |
536 | ||
754661f1 | 537 | static const struct inode_operations cramfs_dir_inode_operations = { |
1da177e4 LT |
538 | .lookup = cramfs_lookup, |
539 | }; | |
540 | ||
ee9b6d61 | 541 | static const struct super_operations cramfs_ops = { |
1da177e4 LT |
542 | .put_super = cramfs_put_super, |
543 | .remount_fs = cramfs_remount, | |
544 | .statfs = cramfs_statfs, | |
82d63fc9 | 545 | .drop_inode = cramfs_drop_inode, |
1da177e4 LT |
546 | }; |
547 | ||
454e2398 DH |
548 | static int cramfs_get_sb(struct file_system_type *fs_type, |
549 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) | |
1da177e4 | 550 | { |
454e2398 DH |
551 | return get_sb_bdev(fs_type, flags, dev_name, data, cramfs_fill_super, |
552 | mnt); | |
1da177e4 LT |
553 | } |
554 | ||
555 | static struct file_system_type cramfs_fs_type = { | |
556 | .owner = THIS_MODULE, | |
557 | .name = "cramfs", | |
558 | .get_sb = cramfs_get_sb, | |
559 | .kill_sb = kill_block_super, | |
560 | .fs_flags = FS_REQUIRES_DEV, | |
561 | }; | |
562 | ||
563 | static int __init init_cramfs_fs(void) | |
564 | { | |
50d44ed0 AD |
565 | int rv; |
566 | ||
567 | rv = cramfs_uncompress_init(); | |
568 | if (rv < 0) | |
569 | return rv; | |
570 | rv = register_filesystem(&cramfs_fs_type); | |
571 | if (rv < 0) | |
572 | cramfs_uncompress_exit(); | |
573 | return rv; | |
1da177e4 LT |
574 | } |
575 | ||
576 | static void __exit exit_cramfs_fs(void) | |
577 | { | |
578 | cramfs_uncompress_exit(); | |
579 | unregister_filesystem(&cramfs_fs_type); | |
580 | } | |
581 | ||
582 | module_init(init_cramfs_fs) | |
583 | module_exit(exit_cramfs_fs) | |
584 | MODULE_LICENSE("GPL"); |