4 * Copyright (C) 1999 Linus Torvalds
6 * Copyright (C) 2000-2002 Transmeta Corporation
8 * Copyright (C) 2003 Kai-Uwe Bloem,
9 * Auerswald GmbH & Co KG, <linux-development@auerswald.de>
10 * - adapted from the www.tuxbox.org u-boot tree, added "ls" command
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License (Version 2) as
14 * published by the Free Software Foundation.
16 * Compressed ROM filesystem for Linux.
19 * add support for resolving symbolic links
23 * These are the VFS interfaces to the compressed ROM filesystem.
24 * The actual compression is based on zlib, see the other files.
29 #include <asm/byteorder.h>
30 #include <linux/stat.h>
31 #include <jffs2/jffs2.h>
32 #include <jffs2/load_kernel.h>
33 #include <cramfs/cramfs_fs.h>
35 /* These two macros may change in future, to provide better st_ino
37 #define CRAMINO(x) (CRAMFS_GET_OFFSET(x) ? CRAMFS_GET_OFFSET(x)<<2 : 1)
38 #define OFFSET(x) ((x)->i_ino)
40 struct cramfs_super super
;
42 /* CPU address space offset calculation macro, struct part_info offset is
43 * device address space offset, so we need to shift it by a device start address. */
44 #if defined(CONFIG_MTD_NOR_FLASH)
45 extern flash_info_t flash_info
[];
46 #define PART_OFFSET(x) ((ulong)x->offset + \
47 flash_info[x->dev->id->num].start[0])
49 #define PART_OFFSET(x) ((ulong)x->offset)
52 static int cramfs_uncompress (unsigned long begin
, unsigned long offset
,
53 unsigned long loadoffset
);
55 static int cramfs_read_super (struct part_info
*info
)
57 unsigned long root_offset
;
59 /* Read the first block and get the superblock from it */
60 memcpy (&super
, (void *) PART_OFFSET(info
), sizeof (super
));
62 /* Do sanity checks on the superblock */
63 if (super
.magic
!= CRAMFS_32 (CRAMFS_MAGIC
)) {
64 /* check at 512 byte offset */
65 memcpy (&super
, (void *) PART_OFFSET(info
) + 512, sizeof (super
));
66 if (super
.magic
!= CRAMFS_32 (CRAMFS_MAGIC
)) {
67 printf ("cramfs: wrong magic\n");
72 /* flags is reused several times, so swab it once */
73 super
.flags
= CRAMFS_32 (super
.flags
);
74 super
.size
= CRAMFS_32 (super
.size
);
76 /* get feature flags first */
77 if (super
.flags
& ~CRAMFS_SUPPORTED_FLAGS
) {
78 printf ("cramfs: unsupported filesystem features\n");
82 /* Check that the root inode is in a sane state */
83 if (!S_ISDIR (CRAMFS_16 (super
.root
.mode
))) {
84 printf ("cramfs: root is not a directory\n");
87 root_offset
= CRAMFS_GET_OFFSET (&(super
.root
)) << 2;
88 if (root_offset
== 0) {
89 printf ("cramfs: empty filesystem");
90 } else if (!(super
.flags
& CRAMFS_FLAG_SHIFTED_ROOT_OFFSET
) &&
91 ((root_offset
!= sizeof (struct cramfs_super
)) &&
92 (root_offset
!= 512 + sizeof (struct cramfs_super
)))) {
93 printf ("cramfs: bad root offset %lu\n", root_offset
);
100 /* Unpack to an allocated buffer, trusting in the inode's size field. */
101 static char *cramfs_uncompress_link (unsigned long begin
, unsigned long offset
)
103 struct cramfs_inode
*inode
= (struct cramfs_inode
*)(begin
+ offset
);
104 unsigned long size
= CRAMFS_24 (inode
->size
);
105 char *link
= malloc (size
+ 1);
107 if (!link
|| cramfs_uncompress (begin
, offset
, (unsigned long)link
) != size
) {
116 static unsigned long cramfs_resolve (unsigned long begin
, unsigned long offset
,
117 unsigned long size
, int raw
,
120 unsigned long inodeoffset
= 0, nextoffset
;
122 while (inodeoffset
< size
) {
123 struct cramfs_inode
*inode
;
127 inode
= (struct cramfs_inode
*) (begin
+ offset
+
131 * Namelengths on disk are shifted by two
132 * and the name padded out to 4-byte boundaries
135 namelen
= CRAMFS_GET_NAMELEN (inode
) << 2;
136 name
= (char *) inode
+ sizeof (struct cramfs_inode
);
139 inodeoffset
+ sizeof (struct cramfs_inode
) + namelen
;
144 if (name
[namelen
- 1])
149 if (!strncmp(filename
, name
, namelen
) &&
150 (namelen
== strlen(filename
))) {
151 char *p
= strtok (NULL
, "/");
153 if (raw
&& (p
== NULL
|| *p
== '\0'))
154 return offset
+ inodeoffset
;
156 if (S_ISDIR (CRAMFS_16 (inode
->mode
))) {
157 return cramfs_resolve (begin
,
163 } else if (S_ISREG (CRAMFS_16 (inode
->mode
))) {
164 return offset
+ inodeoffset
;
165 } else if (S_ISLNK (CRAMFS_16 (inode
->mode
))) {
168 if (p
&& strlen(p
)) {
169 printf ("unsupported symlink to \
170 non-terminal path\n");
173 link
= cramfs_uncompress_link (begin
,
174 offset
+ inodeoffset
);
176 printf ("%*.*s: Error reading link\n",
177 namelen
, namelen
, name
);
179 } else if (link
[0] == '/') {
180 printf ("unsupported symlink to \
185 ret
= cramfs_resolve (begin
,
193 printf ("%*.*s: unsupported file type (%x)\n",
194 namelen
, namelen
, name
,
195 CRAMFS_16 (inode
->mode
));
200 inodeoffset
= nextoffset
;
203 printf ("can't find corresponding entry\n");
207 static int cramfs_uncompress (unsigned long begin
, unsigned long offset
,
208 unsigned long loadoffset
)
210 struct cramfs_inode
*inode
= (struct cramfs_inode
*) (begin
+ offset
);
211 u32
*block_ptrs
= (u32
*)
212 (begin
+ (CRAMFS_GET_OFFSET (inode
) << 2));
213 unsigned long curr_block
= (CRAMFS_GET_OFFSET (inode
) +
214 (((CRAMFS_24 (inode
->size
)) +
216 int size
, total_size
= 0;
219 cramfs_uncompress_init ();
221 for (i
= 0; i
< ((CRAMFS_24 (inode
->size
) + 4095) >> 12); i
++) {
222 size
= cramfs_uncompress_block ((void *) loadoffset
,
223 (void *) (begin
+ curr_block
),
224 (CRAMFS_32 (block_ptrs
[i
]) -
230 curr_block
= CRAMFS_32 (block_ptrs
[i
]);
233 cramfs_uncompress_exit ();
237 int cramfs_load (char *loadoffset
, struct part_info
*info
, char *filename
)
239 unsigned long offset
;
241 if (cramfs_read_super (info
))
244 offset
= cramfs_resolve (PART_OFFSET(info
),
245 CRAMFS_GET_OFFSET (&(super
.root
)) << 2,
246 CRAMFS_24 (super
.root
.size
), 0,
247 strtok (filename
, "/"));
252 return cramfs_uncompress (PART_OFFSET(info
), offset
,
253 (unsigned long) loadoffset
);
256 static int cramfs_list_inode (struct part_info
*info
, unsigned long offset
)
258 struct cramfs_inode
*inode
= (struct cramfs_inode
*)
259 (PART_OFFSET(info
) + offset
);
261 int namelen
, nextoff
;
264 * Namelengths on disk are shifted by two
265 * and the name padded out to 4-byte boundaries
268 namelen
= CRAMFS_GET_NAMELEN (inode
) << 2;
269 name
= (char *) inode
+ sizeof (struct cramfs_inode
);
275 if (name
[namelen
- 1])
280 printf (" %s %8d %*.*s", mkmodestr (CRAMFS_16 (inode
->mode
), str
),
281 CRAMFS_24 (inode
->size
), namelen
, namelen
, name
);
283 if ((CRAMFS_16 (inode
->mode
) & S_IFMT
) == S_IFLNK
) {
284 char *link
= cramfs_uncompress_link (PART_OFFSET(info
), offset
);
286 printf (" -> %s\n", link
);
288 printf (" [Error reading link]\n");
296 int cramfs_ls (struct part_info
*info
, char *filename
)
298 struct cramfs_inode
*inode
;
299 unsigned long inodeoffset
= 0, nextoffset
;
300 unsigned long offset
, size
;
302 if (cramfs_read_super (info
))
305 if (strlen (filename
) == 0 || !strcmp (filename
, "/")) {
306 /* Root directory. Use root inode in super block */
307 offset
= CRAMFS_GET_OFFSET (&(super
.root
)) << 2;
308 size
= CRAMFS_24 (super
.root
.size
);
310 /* Resolve the path */
311 offset
= cramfs_resolve (PART_OFFSET(info
),
312 CRAMFS_GET_OFFSET (&(super
.root
)) <<
313 2, CRAMFS_24 (super
.root
.size
), 1,
314 strtok (filename
, "/"));
319 /* Resolving was successful. Examine the inode */
320 inode
= (struct cramfs_inode
*) (PART_OFFSET(info
) + offset
);
321 if (!S_ISDIR (CRAMFS_16 (inode
->mode
))) {
322 /* It's not a directory - list it, and that's that */
323 return (cramfs_list_inode (info
, offset
) > 0);
326 /* It's a directory. List files within */
327 offset
= CRAMFS_GET_OFFSET (inode
) << 2;
328 size
= CRAMFS_24 (inode
->size
);
331 /* List the given directory */
332 while (inodeoffset
< size
) {
333 inode
= (struct cramfs_inode
*) (PART_OFFSET(info
) + offset
+
336 nextoffset
= cramfs_list_inode (info
, offset
+ inodeoffset
);
339 inodeoffset
+= sizeof (struct cramfs_inode
) + nextoffset
;
345 int cramfs_info (struct part_info
*info
)
347 if (cramfs_read_super (info
))
350 printf ("size: 0x%x (%u)\n", super
.size
, super
.size
);
352 if (super
.flags
!= 0) {
354 if (super
.flags
& CRAMFS_FLAG_FSID_VERSION_2
)
355 printf ("\tFSID version 2\n");
356 if (super
.flags
& CRAMFS_FLAG_SORTED_DIRS
)
357 printf ("\tsorted dirs\n");
358 if (super
.flags
& CRAMFS_FLAG_HOLES
)
359 printf ("\tholes\n");
360 if (super
.flags
& CRAMFS_FLAG_SHIFTED_ROOT_OFFSET
)
361 printf ("\tshifted root offset\n");
364 printf ("fsid:\n\tcrc: 0x%x\n\tedition: 0x%x\n",
365 super
.fsid
.crc
, super
.fsid
.edition
);
366 printf ("name: %16s\n", super
.name
);
371 int cramfs_check (struct part_info
*info
)
373 struct cramfs_super
*sb
;
375 if (info
->dev
->id
->type
!= MTD_DEV_TYPE_NOR
)
378 sb
= (struct cramfs_super
*) PART_OFFSET(info
);
379 if (sb
->magic
!= CRAMFS_32 (CRAMFS_MAGIC
)) {
380 /* check at 512 byte offset */
381 sb
= (struct cramfs_super
*) (PART_OFFSET(info
) + 512);
382 if (sb
->magic
!= CRAMFS_32 (CRAMFS_MAGIC
))