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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Squashfs - a compressed read only filesystem for Linux
4 *
5 * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
6 * Phillip Lougher <[email protected]>
7 *
8 * super.c
9 */
10
11/*
12 * This file implements code to read the superblock, read and initialise
13 * in-memory structures at mount time, and all the VFS glue code to register
14 * the filesystem.
15 */
16
17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19#include <linux/blkdev.h>
20#include <linux/fs.h>
21#include <linux/fs_context.h>
22#include <linux/fs_parser.h>
23#include <linux/vfs.h>
24#include <linux/slab.h>
25#include <linux/mutex.h>
26#include <linux/seq_file.h>
27#include <linux/pagemap.h>
28#include <linux/init.h>
29#include <linux/module.h>
30#include <linux/magic.h>
31#include <linux/xattr.h>
32
33#include "squashfs_fs.h"
34#include "squashfs_fs_sb.h"
35#include "squashfs_fs_i.h"
36#include "squashfs.h"
37#include "decompressor.h"
38#include "xattr.h"
39
40static struct file_system_type squashfs_fs_type;
41static const struct super_operations squashfs_super_ops;
42
43enum Opt_errors {
44 Opt_errors_continue,
45 Opt_errors_panic,
46};
47
48enum squashfs_param {
49 Opt_errors,
50 Opt_threads,
51};
52
53struct squashfs_mount_opts {
54 enum Opt_errors errors;
55 const struct squashfs_decompressor_thread_ops *thread_ops;
56 int thread_num;
57};
58
59static const struct constant_table squashfs_param_errors[] = {
60 {"continue", Opt_errors_continue },
61 {"panic", Opt_errors_panic },
62 {}
63};
64
65static const struct fs_parameter_spec squashfs_fs_parameters[] = {
66 fsparam_enum("errors", Opt_errors, squashfs_param_errors),
67 fsparam_string("threads", Opt_threads),
68 {}
69};
70
71
72static int squashfs_parse_param_threads_str(const char *str, struct squashfs_mount_opts *opts)
73{
74#ifdef CONFIG_SQUASHFS_CHOICE_DECOMP_BY_MOUNT
75 if (strcmp(str, "single") == 0) {
76 opts->thread_ops = &squashfs_decompressor_single;
77 return 0;
78 }
79 if (strcmp(str, "multi") == 0) {
80 opts->thread_ops = &squashfs_decompressor_multi;
81 return 0;
82 }
83 if (strcmp(str, "percpu") == 0) {
84 opts->thread_ops = &squashfs_decompressor_percpu;
85 return 0;
86 }
87#endif
88 return -EINVAL;
89}
90
91static int squashfs_parse_param_threads_num(const char *str, struct squashfs_mount_opts *opts)
92{
93#ifdef CONFIG_SQUASHFS_MOUNT_DECOMP_THREADS
94 int ret;
95 unsigned long num;
96
97 ret = kstrtoul(str, 0, &num);
98 if (ret != 0)
99 return -EINVAL;
100 if (num > 1) {
101 opts->thread_ops = &squashfs_decompressor_multi;
102 if (num > opts->thread_ops->max_decompressors())
103 return -EINVAL;
104 opts->thread_num = (int)num;
105 return 0;
106 }
107#ifdef CONFIG_SQUASHFS_DECOMP_SINGLE
108 if (num == 1) {
109 opts->thread_ops = &squashfs_decompressor_single;
110 opts->thread_num = 1;
111 return 0;
112 }
113#endif
114#endif /* !CONFIG_SQUASHFS_MOUNT_DECOMP_THREADS */
115 return -EINVAL;
116}
117
118static int squashfs_parse_param_threads(const char *str, struct squashfs_mount_opts *opts)
119{
120 int ret = squashfs_parse_param_threads_str(str, opts);
121
122 if (ret == 0)
123 return ret;
124 return squashfs_parse_param_threads_num(str, opts);
125}
126
127static int squashfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
128{
129 struct squashfs_mount_opts *opts = fc->fs_private;
130 struct fs_parse_result result;
131 int opt;
132
133 opt = fs_parse(fc, squashfs_fs_parameters, param, &result);
134 if (opt < 0)
135 return opt;
136
137 switch (opt) {
138 case Opt_errors:
139 opts->errors = result.uint_32;
140 break;
141 case Opt_threads:
142 if (squashfs_parse_param_threads(param->string, opts) != 0)
143 return -EINVAL;
144 break;
145 default:
146 return -EINVAL;
147 }
148
149 return 0;
150}
151
152static const struct squashfs_decompressor *supported_squashfs_filesystem(
153 struct fs_context *fc,
154 short major, short minor, short id)
155{
156 const struct squashfs_decompressor *decompressor;
157
158 if (major < SQUASHFS_MAJOR) {
159 errorf(fc, "Major/Minor mismatch, older Squashfs %d.%d "
160 "filesystems are unsupported", major, minor);
161 return NULL;
162 } else if (major > SQUASHFS_MAJOR || minor > SQUASHFS_MINOR) {
163 errorf(fc, "Major/Minor mismatch, trying to mount newer "
164 "%d.%d filesystem", major, minor);
165 errorf(fc, "Please update your kernel");
166 return NULL;
167 }
168
169 decompressor = squashfs_lookup_decompressor(id);
170 if (!decompressor->supported) {
171 errorf(fc, "Filesystem uses \"%s\" compression. This is not supported",
172 decompressor->name);
173 return NULL;
174 }
175
176 return decompressor;
177}
178
179
180static int squashfs_fill_super(struct super_block *sb, struct fs_context *fc)
181{
182 struct squashfs_mount_opts *opts = fc->fs_private;
183 struct squashfs_sb_info *msblk;
184 struct squashfs_super_block *sblk = NULL;
185 struct inode *root;
186 long long root_inode;
187 unsigned short flags;
188 unsigned int fragments;
189 u64 lookup_table_start, xattr_id_table_start, next_table;
190 int err, devblksize = sb_min_blocksize(sb, SQUASHFS_DEVBLK_SIZE);
191
192 TRACE("Entered squashfs_fill_superblock\n");
193
194 if (!devblksize) {
195 errorf(fc, "squashfs: unable to set blocksize\n");
196 return -EINVAL;
197 }
198
199 sb->s_fs_info = kzalloc_obj(*msblk);
200 if (sb->s_fs_info == NULL) {
201 ERROR("Failed to allocate squashfs_sb_info\n");
202 return -ENOMEM;
203 }
204 msblk = sb->s_fs_info;
205 msblk->thread_ops = opts->thread_ops;
206
207 msblk->panic_on_errors = (opts->errors == Opt_errors_panic);
208
209 msblk->devblksize = devblksize;
210 msblk->devblksize_log2 = ffz(~msblk->devblksize);
211
212 mutex_init(&msblk->meta_index_mutex);
213
214 /*
215 * msblk->bytes_used is checked in squashfs_read_table to ensure reads
216 * are not beyond filesystem end. But as we're using
217 * squashfs_read_table here to read the superblock (including the value
218 * of bytes_used) we need to set it to an initial sensible dummy value
219 */
220 msblk->bytes_used = sizeof(*sblk);
221 sblk = squashfs_read_table(sb, SQUASHFS_START, sizeof(*sblk));
222
223 if (IS_ERR(sblk)) {
224 errorf(fc, "unable to read squashfs_super_block");
225 err = PTR_ERR(sblk);
226 sblk = NULL;
227 goto failed_mount;
228 }
229
230 err = -EINVAL;
231
232 /* Check it is a SQUASHFS superblock */
233 sb->s_magic = le32_to_cpu(sblk->s_magic);
234 if (sb->s_magic != SQUASHFS_MAGIC) {
235 if (!(fc->sb_flags & SB_SILENT))
236 errorf(fc, "Can't find a SQUASHFS superblock on %pg",
237 sb->s_bdev);
238 goto failed_mount;
239 }
240
241 if (opts->thread_num == 0) {
242 msblk->max_thread_num = msblk->thread_ops->max_decompressors();
243 } else {
244 msblk->max_thread_num = opts->thread_num;
245 }
246
247 /* Check the MAJOR & MINOR versions and lookup compression type */
248 msblk->decompressor = supported_squashfs_filesystem(
249 fc,
250 le16_to_cpu(sblk->s_major),
251 le16_to_cpu(sblk->s_minor),
252 le16_to_cpu(sblk->compression));
253 if (msblk->decompressor == NULL)
254 goto failed_mount;
255
256 /* Check the filesystem does not extend beyond the end of the
257 block device */
258 msblk->bytes_used = le64_to_cpu(sblk->bytes_used);
259 if (msblk->bytes_used < 0 ||
260 msblk->bytes_used > bdev_nr_bytes(sb->s_bdev))
261 goto failed_mount;
262
263 /* Check block size for sanity */
264 msblk->block_size = le32_to_cpu(sblk->block_size);
265 if (msblk->block_size > SQUASHFS_FILE_MAX_SIZE)
266 goto insanity;
267
268 /*
269 * Check the system page size is not larger than the filesystem
270 * block size (by default 128K). This is currently not supported.
271 */
272 if (PAGE_SIZE > msblk->block_size) {
273 errorf(fc, "Page size > filesystem block size (%d). This is "
274 "currently not supported!", msblk->block_size);
275 goto failed_mount;
276 }
277
278 /* Check block log for sanity */
279 msblk->block_log = le16_to_cpu(sblk->block_log);
280 if (msblk->block_log > SQUASHFS_FILE_MAX_LOG)
281 goto failed_mount;
282
283 /* Check that block_size and block_log match */
284 if (msblk->block_size != (1 << msblk->block_log))
285 goto insanity;
286
287 /* Check the root inode for sanity */
288 root_inode = le64_to_cpu(sblk->root_inode);
289 if (SQUASHFS_INODE_OFFSET(root_inode) > SQUASHFS_METADATA_SIZE)
290 goto insanity;
291
292 msblk->inode_table = le64_to_cpu(sblk->inode_table_start);
293 msblk->directory_table = le64_to_cpu(sblk->directory_table_start);
294 msblk->inodes = le32_to_cpu(sblk->inodes);
295 msblk->fragments = le32_to_cpu(sblk->fragments);
296 msblk->ids = le16_to_cpu(sblk->no_ids);
297 flags = le16_to_cpu(sblk->flags);
298
299 TRACE("Found valid superblock on %pg\n", sb->s_bdev);
300 TRACE("Inodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(flags)
301 ? "un" : "");
302 TRACE("Data is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(flags)
303 ? "un" : "");
304 TRACE("Filesystem size %lld bytes\n", msblk->bytes_used);
305 TRACE("Block size %d\n", msblk->block_size);
306 TRACE("Number of inodes %d\n", msblk->inodes);
307 TRACE("Number of fragments %d\n", msblk->fragments);
308 TRACE("Number of ids %d\n", msblk->ids);
309 TRACE("sblk->inode_table_start %llx\n", msblk->inode_table);
310 TRACE("sblk->directory_table_start %llx\n", msblk->directory_table);
311 TRACE("sblk->fragment_table_start %llx\n",
312 (u64) le64_to_cpu(sblk->fragment_table_start));
313 TRACE("sblk->id_table_start %llx\n",
314 (u64) le64_to_cpu(sblk->id_table_start));
315
316 sb->s_maxbytes = MAX_LFS_FILESIZE;
317 sb->s_time_min = 0;
318 sb->s_time_max = U32_MAX;
319 sb->s_flags |= SB_RDONLY;
320 sb->s_op = &squashfs_super_ops;
321
322 msblk->block_cache = squashfs_cache_init("metadata",
323 SQUASHFS_CACHED_BLKS, SQUASHFS_METADATA_SIZE);
324 if (IS_ERR(msblk->block_cache)) {
325 err = PTR_ERR(msblk->block_cache);
326 goto failed_mount;
327 }
328
329 /* Allocate read_page block */
330 msblk->read_page = squashfs_cache_init("data",
331 SQUASHFS_READ_PAGES, msblk->block_size);
332 if (IS_ERR(msblk->read_page)) {
333 errorf(fc, "Failed to allocate read_page block");
334 err = PTR_ERR(msblk->read_page);
335 goto failed_mount;
336 }
337
338 if (msblk->devblksize == PAGE_SIZE) {
339 struct inode *cache = new_inode(sb);
340
341 if (cache == NULL) {
342 err = -ENOMEM;
343 goto failed_mount;
344 }
345
346 set_nlink(cache, 1);
347 cache->i_size = OFFSET_MAX;
348 mapping_set_gfp_mask(cache->i_mapping, GFP_NOFS);
349
350 msblk->cache_mapping = cache->i_mapping;
351 }
352
353 msblk->stream = squashfs_decompressor_setup(sb, flags);
354 if (IS_ERR(msblk->stream)) {
355 err = PTR_ERR(msblk->stream);
356 msblk->stream = NULL;
357 goto insanity;
358 }
359
360 /* Handle xattrs */
361 sb->s_xattr = squashfs_xattr_handlers;
362 xattr_id_table_start = le64_to_cpu(sblk->xattr_id_table_start);
363 if (xattr_id_table_start == SQUASHFS_INVALID_BLK) {
364 next_table = msblk->bytes_used;
365 goto allocate_id_index_table;
366 }
367
368 /* Allocate and read xattr id lookup table */
369 msblk->xattr_id_table = squashfs_read_xattr_id_table(sb,
370 xattr_id_table_start, &msblk->xattr_table, &msblk->xattr_ids);
371 if (IS_ERR(msblk->xattr_id_table)) {
372 errorf(fc, "unable to read xattr id index table");
373 err = PTR_ERR(msblk->xattr_id_table);
374 msblk->xattr_id_table = NULL;
375 if (err != -ENOTSUPP)
376 goto failed_mount;
377 }
378 next_table = msblk->xattr_table;
379
380allocate_id_index_table:
381 /* Allocate and read id index table */
382 msblk->id_table = squashfs_read_id_index_table(sb,
383 le64_to_cpu(sblk->id_table_start), next_table, msblk->ids);
384 if (IS_ERR(msblk->id_table)) {
385 errorf(fc, "unable to read id index table");
386 err = PTR_ERR(msblk->id_table);
387 msblk->id_table = NULL;
388 goto failed_mount;
389 }
390 next_table = le64_to_cpu(msblk->id_table[0]);
391
392 /* Handle inode lookup table */
393 lookup_table_start = le64_to_cpu(sblk->lookup_table_start);
394 if (lookup_table_start == SQUASHFS_INVALID_BLK)
395 goto handle_fragments;
396
397 /* Allocate and read inode lookup table */
398 msblk->inode_lookup_table = squashfs_read_inode_lookup_table(sb,
399 lookup_table_start, next_table, msblk->inodes);
400 if (IS_ERR(msblk->inode_lookup_table)) {
401 errorf(fc, "unable to read inode lookup table");
402 err = PTR_ERR(msblk->inode_lookup_table);
403 msblk->inode_lookup_table = NULL;
404 goto failed_mount;
405 }
406 next_table = le64_to_cpu(msblk->inode_lookup_table[0]);
407
408 sb->s_export_op = &squashfs_export_ops;
409
410handle_fragments:
411 fragments = msblk->fragments;
412 if (fragments == 0)
413 goto check_directory_table;
414
415 msblk->fragment_cache = squashfs_cache_init("fragment",
416 min(SQUASHFS_CACHED_FRAGMENTS, fragments), msblk->block_size);
417 if (IS_ERR(msblk->fragment_cache)) {
418 err = PTR_ERR(msblk->fragment_cache);
419 goto failed_mount;
420 }
421
422 /* Allocate and read fragment index table */
423 msblk->fragment_index = squashfs_read_fragment_index_table(sb,
424 le64_to_cpu(sblk->fragment_table_start), next_table, fragments);
425 if (IS_ERR(msblk->fragment_index)) {
426 errorf(fc, "unable to read fragment index table");
427 err = PTR_ERR(msblk->fragment_index);
428 msblk->fragment_index = NULL;
429 goto failed_mount;
430 }
431 next_table = le64_to_cpu(msblk->fragment_index[0]);
432
433check_directory_table:
434 /* Sanity check directory_table */
435 if (msblk->directory_table > next_table) {
436 err = -EINVAL;
437 goto insanity;
438 }
439
440 /* Sanity check inode_table */
441 if (msblk->inode_table >= msblk->directory_table) {
442 err = -EINVAL;
443 goto insanity;
444 }
445
446 /* allocate root */
447 root = new_inode(sb);
448 if (!root) {
449 err = -ENOMEM;
450 goto failed_mount;
451 }
452
453 err = squashfs_read_inode(root, root_inode);
454 if (err) {
455 make_bad_inode(root);
456 iput(root);
457 goto failed_mount;
458 }
459 insert_inode_hash(root);
460
461 sb->s_root = d_make_root(root);
462 if (sb->s_root == NULL) {
463 ERROR("Root inode create failed\n");
464 err = -ENOMEM;
465 goto failed_mount;
466 }
467
468 TRACE("Leaving squashfs_fill_super\n");
469 kfree(sblk);
470 return 0;
471
472insanity:
473 errorf(fc, "squashfs image failed sanity check");
474failed_mount:
475 squashfs_cache_delete(msblk->block_cache);
476 squashfs_cache_delete(msblk->fragment_cache);
477 squashfs_cache_delete(msblk->read_page);
478 if (msblk->cache_mapping)
479 iput(msblk->cache_mapping->host);
480 msblk->thread_ops->destroy(msblk);
481 kfree(msblk->inode_lookup_table);
482 kfree(msblk->fragment_index);
483 kfree(msblk->id_table);
484 kfree(msblk->xattr_id_table);
485 kfree(sb->s_fs_info);
486 sb->s_fs_info = NULL;
487 kfree(sblk);
488 return err;
489}
490
491static int squashfs_get_tree(struct fs_context *fc)
492{
493 return get_tree_bdev(fc, squashfs_fill_super);
494}
495
496static int squashfs_reconfigure(struct fs_context *fc)
497{
498 struct super_block *sb = fc->root->d_sb;
499 struct squashfs_sb_info *msblk = sb->s_fs_info;
500 struct squashfs_mount_opts *opts = fc->fs_private;
501
502 sync_filesystem(fc->root->d_sb);
503 fc->sb_flags |= SB_RDONLY;
504
505 msblk->panic_on_errors = (opts->errors == Opt_errors_panic);
506
507 return 0;
508}
509
510static void squashfs_free_fs_context(struct fs_context *fc)
511{
512 kfree(fc->fs_private);
513}
514
515static const struct fs_context_operations squashfs_context_ops = {
516 .get_tree = squashfs_get_tree,
517 .free = squashfs_free_fs_context,
518 .parse_param = squashfs_parse_param,
519 .reconfigure = squashfs_reconfigure,
520};
521
522static int squashfs_show_options(struct seq_file *s, struct dentry *root)
523{
524 struct super_block *sb = root->d_sb;
525 struct squashfs_sb_info *msblk = sb->s_fs_info;
526
527 if (msblk->panic_on_errors)
528 seq_puts(s, ",errors=panic");
529 else
530 seq_puts(s, ",errors=continue");
531
532#ifdef CONFIG_SQUASHFS_CHOICE_DECOMP_BY_MOUNT
533 if (msblk->thread_ops == &squashfs_decompressor_single) {
534 seq_puts(s, ",threads=single");
535 return 0;
536 }
537 if (msblk->thread_ops == &squashfs_decompressor_percpu) {
538 seq_puts(s, ",threads=percpu");
539 return 0;
540 }
541#endif
542#ifdef CONFIG_SQUASHFS_MOUNT_DECOMP_THREADS
543 seq_printf(s, ",threads=%d", msblk->max_thread_num);
544#endif
545 return 0;
546}
547
548static int squashfs_init_fs_context(struct fs_context *fc)
549{
550 struct squashfs_mount_opts *opts;
551
552 opts = kzalloc_obj(*opts);
553 if (!opts)
554 return -ENOMEM;
555
556#ifdef CONFIG_SQUASHFS_DECOMP_SINGLE
557 opts->thread_ops = &squashfs_decompressor_single;
558#elif defined(CONFIG_SQUASHFS_DECOMP_MULTI)
559 opts->thread_ops = &squashfs_decompressor_multi;
560#elif defined(CONFIG_SQUASHFS_DECOMP_MULTI_PERCPU)
561 opts->thread_ops = &squashfs_decompressor_percpu;
562#else
563#error "fail: unknown squashfs decompression thread mode?"
564#endif
565 opts->thread_num = 0;
566 fc->fs_private = opts;
567 fc->ops = &squashfs_context_ops;
568 return 0;
569}
570
571static int squashfs_statfs(struct dentry *dentry, struct kstatfs *buf)
572{
573 struct squashfs_sb_info *msblk = dentry->d_sb->s_fs_info;
574 u64 id = huge_encode_dev(dentry->d_sb->s_bdev->bd_dev);
575
576 TRACE("Entered squashfs_statfs\n");
577
578 buf->f_type = SQUASHFS_MAGIC;
579 buf->f_bsize = msblk->block_size;
580 buf->f_blocks = ((msblk->bytes_used - 1) >> msblk->block_log) + 1;
581 buf->f_bfree = buf->f_bavail = 0;
582 buf->f_files = msblk->inodes;
583 buf->f_ffree = 0;
584 buf->f_namelen = SQUASHFS_NAME_LEN;
585 buf->f_fsid = u64_to_fsid(id);
586
587 return 0;
588}
589
590
591static void squashfs_put_super(struct super_block *sb)
592{
593 if (sb->s_fs_info) {
594 struct squashfs_sb_info *sbi = sb->s_fs_info;
595 squashfs_cache_delete(sbi->block_cache);
596 squashfs_cache_delete(sbi->fragment_cache);
597 squashfs_cache_delete(sbi->read_page);
598 if (sbi->cache_mapping)
599 iput(sbi->cache_mapping->host);
600 sbi->thread_ops->destroy(sbi);
601 kfree(sbi->id_table);
602 kfree(sbi->fragment_index);
603 kfree(sbi->meta_index);
604 kfree(sbi->inode_lookup_table);
605 kfree(sbi->xattr_id_table);
606 kfree(sb->s_fs_info);
607 sb->s_fs_info = NULL;
608 }
609}
610
611static struct kmem_cache *squashfs_inode_cachep;
612
613
614static void init_once(void *foo)
615{
616 struct squashfs_inode_info *ei = foo;
617
618 inode_init_once(&ei->vfs_inode);
619}
620
621
622static int __init init_inodecache(void)
623{
624 squashfs_inode_cachep = kmem_cache_create("squashfs_inode_cache",
625 sizeof(struct squashfs_inode_info), 0,
626 SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT,
627 init_once);
628
629 return squashfs_inode_cachep ? 0 : -ENOMEM;
630}
631
632
633static void destroy_inodecache(void)
634{
635 /*
636 * Make sure all delayed rcu free inodes are flushed before we
637 * destroy cache.
638 */
639 rcu_barrier();
640 kmem_cache_destroy(squashfs_inode_cachep);
641}
642
643
644static int __init init_squashfs_fs(void)
645{
646 int err = init_inodecache();
647
648 if (err)
649 return err;
650
651 err = register_filesystem(&squashfs_fs_type);
652 if (err) {
653 destroy_inodecache();
654 return err;
655 }
656
657 pr_info("version 4.0 (2009/01/31) Phillip Lougher\n");
658
659 return 0;
660}
661
662
663static void __exit exit_squashfs_fs(void)
664{
665 unregister_filesystem(&squashfs_fs_type);
666 destroy_inodecache();
667}
668
669
670static struct inode *squashfs_alloc_inode(struct super_block *sb)
671{
672 struct squashfs_inode_info *ei =
673 alloc_inode_sb(sb, squashfs_inode_cachep, GFP_KERNEL);
674
675 return ei ? &ei->vfs_inode : NULL;
676}
677
678
679static void squashfs_free_inode(struct inode *inode)
680{
681 kmem_cache_free(squashfs_inode_cachep, squashfs_i(inode));
682}
683
684static struct file_system_type squashfs_fs_type = {
685 .owner = THIS_MODULE,
686 .name = "squashfs",
687 .init_fs_context = squashfs_init_fs_context,
688 .parameters = squashfs_fs_parameters,
689 .kill_sb = kill_block_super,
690 .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
691};
692MODULE_ALIAS_FS("squashfs");
693
694static const struct super_operations squashfs_super_ops = {
695 .alloc_inode = squashfs_alloc_inode,
696 .free_inode = squashfs_free_inode,
697 .statfs = squashfs_statfs,
698 .put_super = squashfs_put_super,
699 .show_options = squashfs_show_options,
700};
701
702module_init(init_squashfs_fs);
703module_exit(exit_squashfs_fs);
704MODULE_DESCRIPTION("squashfs 4.0, a compressed read-only filesystem");
705MODULE_AUTHOR("Phillip Lougher <[email protected]>");
706MODULE_LICENSE("GPL");