[people/ms/u-boot.git] / fs / cramfs / cramfs.c

/*
 * cramfs.c
 *
 * Copyright (C) 1999 Linus Torvalds
 *
 * Copyright (C) 2000-2002 Transmeta Corporation
 *
 * Copyright (C) 2003 Kai-Uwe Bloem,
 * Auerswald GmbH & Co KG, <linux-development@auerswald.de>
 * - adapted from the www.tuxbox.org u-boot tree, added "ls" command
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License (Version 2) as
 * published by the Free Software Foundation.
 *
 * Compressed ROM filesystem for Linux.
 *
 * TODO:
 * add support for resolving symbolic links
 */

/*
 * These are the VFS interfaces to the compressed ROM filesystem.
 * The actual compression is based on zlib, see the other files.
 */

#include <common.h>
#include <malloc.h>
#include <asm/byteorder.h>
#include <linux/stat.h>
#include <jffs2/jffs2.h>
#include <jffs2/load_kernel.h>
#include <cramfs/cramfs_fs.h>

/* These two macros may change in future, to provide better st_ino
   semantics. */
#define CRAMINO(x)	(CRAMFS_GET_OFFSET(x) ? CRAMFS_GET_OFFSET(x)<<2 : 1)
#define OFFSET(x)	((x)->i_ino)

struct cramfs_super super;

/* CPU address space offset calculation macro, struct part_info offset is
 * device address space offset, so we need to shift it by a device start address. */
extern flash_info_t flash_info[];
#define PART_OFFSET(x)	(x->offset + flash_info[x->dev->id->num].start[0])

static int cramfs_read_super (struct part_info *info)
{
	unsigned long root_offset;

	/* Read the first block and get the superblock from it */
	memcpy (&super, (void *) PART_OFFSET(info), sizeof (super));

	/* Do sanity checks on the superblock */
	if (super.magic != CRAMFS_32 (CRAMFS_MAGIC)) {
		/* check at 512 byte offset */
		memcpy (&super, (void *) PART_OFFSET(info) + 512, sizeof (super));
		if (super.magic != CRAMFS_32 (CRAMFS_MAGIC)) {
			printf ("cramfs: wrong magic\n");
			return -1;
		}
	}

	/* flags is reused several times, so swab it once */
	super.flags = CRAMFS_32 (super.flags);
	super.size = CRAMFS_32 (super.size);

	/* get feature flags first */
	if (super.flags & ~CRAMFS_SUPPORTED_FLAGS) {
		printf ("cramfs: unsupported filesystem features\n");
		return -1;
	}

	/* Check that the root inode is in a sane state */
	if (!S_ISDIR (CRAMFS_16 (super.root.mode))) {
		printf ("cramfs: root is not a directory\n");
		return -1;
	}
	root_offset = CRAMFS_GET_OFFSET (&(super.root)) << 2;
	if (root_offset == 0) {
		printf ("cramfs: empty filesystem");
	} else if (!(super.flags & CRAMFS_FLAG_SHIFTED_ROOT_OFFSET) &&
		   ((root_offset != sizeof (struct cramfs_super)) &&
		    (root_offset != 512 + sizeof (struct cramfs_super)))) {
		printf ("cramfs: bad root offset %lu\n", root_offset);
		return -1;
	}

	return 0;
}

static unsigned long cramfs_resolve (unsigned long begin, unsigned long offset,
				     unsigned long size, int raw,
				     char *filename)
{
	unsigned long inodeoffset = 0, nextoffset;

	while (inodeoffset < size) {
		struct cramfs_inode *inode;
		char *name;
		int namelen;

		inode = (struct cramfs_inode *) (begin + offset +
						 inodeoffset);

		/*
		 * Namelengths on disk are shifted by two
		 * and the name padded out to 4-byte boundaries
		 * with zeroes.
		 */
		namelen = CRAMFS_GET_NAMELEN (inode) << 2;
		name = (char *) inode + sizeof (struct cramfs_inode);

		nextoffset =
			inodeoffset + sizeof (struct cramfs_inode) + namelen;

		for (;;) {
			if (!namelen)
				return -1;
			if (name[namelen - 1])
				break;
			namelen--;
		}

		if (!strncmp (filename, name, namelen)) {
			char *p = strtok (NULL, "/");

			if (raw && (p == NULL || *p == '\0'))
				return offset + inodeoffset;

			if (S_ISDIR (CRAMFS_16 (inode->mode))) {
				return cramfs_resolve (begin,
						       CRAMFS_GET_OFFSET
						       (inode) << 2,
						       CRAMFS_24 (inode->
								  size), raw,
						       p);
			} else if (S_ISREG (CRAMFS_16 (inode->mode))) {
				return offset + inodeoffset;
			} else {
				printf ("%*.*s: unsupported file type (%x)\n",
					namelen, namelen, name,
					CRAMFS_16 (inode->mode));
				return 0;
			}
		}

		inodeoffset = nextoffset;
	}

	printf ("can't find corresponding entry\n");
	return 0;
}

static int cramfs_uncompress (unsigned long begin, unsigned long offset,
			      unsigned long loadoffset)
{
	struct cramfs_inode *inode = (struct cramfs_inode *) (begin + offset);
	unsigned long *block_ptrs = (unsigned long *)
		(begin + (CRAMFS_GET_OFFSET (inode) << 2));
	unsigned long curr_block = (CRAMFS_GET_OFFSET (inode) +
				    (((CRAMFS_24 (inode->size)) +
				      4095) >> 12)) << 2;
	int size, total_size = 0;
	int i;

	cramfs_uncompress_init ();

	for (i = 0; i < ((CRAMFS_24 (inode->size) + 4095) >> 12); i++) {
		size = cramfs_uncompress_block ((void *) loadoffset,
						(void *) (begin + curr_block),
						(CRAMFS_32 (block_ptrs[i]) -
						 curr_block));
		if (size < 0)
			return size;
		loadoffset += size;
		total_size += size;
		curr_block = CRAMFS_32 (block_ptrs[i]);
	}

	cramfs_uncompress_exit ();
	return total_size;
}

int cramfs_load (char *loadoffset, struct part_info *info, char *filename)
{
	unsigned long offset;

	if (cramfs_read_super (info))
		return -1;

	offset = cramfs_resolve (PART_OFFSET(info),
				 CRAMFS_GET_OFFSET (&(super.root)) << 2,
				 CRAMFS_24 (super.root.size), 0,
				 strtok (filename, "/"));

	if (offset <= 0)
		return offset;

	return cramfs_uncompress (PART_OFFSET(info), offset,
				  (unsigned long) loadoffset);
}

static int cramfs_list_inode (struct part_info *info, unsigned long offset)
{
	struct cramfs_inode *inode = (struct cramfs_inode *)
		(PART_OFFSET(info) + offset);
	char *name, str[20];
	int namelen, nextoff;

	/*
	 * Namelengths on disk are shifted by two
	 * and the name padded out to 4-byte boundaries
	 * with zeroes.
	 */
	namelen = CRAMFS_GET_NAMELEN (inode) << 2;
	name = (char *) inode + sizeof (struct cramfs_inode);
	nextoff = namelen;

	for (;;) {
		if (!namelen)
			return namelen;
		if (name[namelen - 1])
			break;
		namelen--;
	}

	printf (" %s %8d %*.*s", mkmodestr (CRAMFS_16 (inode->mode), str),
		CRAMFS_24 (inode->size), namelen, namelen, name);

	if ((CRAMFS_16 (inode->mode) & S_IFMT) == S_IFLNK) {
		/* symbolic link.
		 * Unpack the link target, trusting in the inode's size field.
		 */
		unsigned long size = CRAMFS_24 (inode->size);
		char *link = malloc (size);

		if (link != NULL && cramfs_uncompress (PART_OFFSET(info), offset,
						       (unsigned long) link)
		    == size)
			printf (" -> %*.*s\n", (int) size, (int) size, link);
		else
			printf (" [Error reading link]\n");
		if (link)
			free (link);
	} else
		printf ("\n");

	return nextoff;
}

int cramfs_ls (struct part_info *info, char *filename)
{
	struct cramfs_inode *inode;
	unsigned long inodeoffset = 0, nextoffset;
	unsigned long offset, size;

	if (cramfs_read_super (info))
		return -1;

	if (strlen (filename) == 0 || !strcmp (filename, "/")) {
		/* Root directory. Use root inode in super block */
		offset = CRAMFS_GET_OFFSET (&(super.root)) << 2;
		size = CRAMFS_24 (super.root.size);
	} else {
		/* Resolve the path */
		offset = cramfs_resolve (PART_OFFSET(info),
					 CRAMFS_GET_OFFSET (&(super.root)) <<
					 2, CRAMFS_24 (super.root.size), 1,
					 strtok (filename, "/"));

		if (offset <= 0)
			return offset;

		/* Resolving was successful. Examine the inode */
		inode = (struct cramfs_inode *) (PART_OFFSET(info) + offset);
		if (!S_ISDIR (CRAMFS_16 (inode->mode))) {
			/* It's not a directory - list it, and that's that */
			return (cramfs_list_inode (info, offset) > 0);
		}

		/* It's a directory. List files within */
		offset = CRAMFS_GET_OFFSET (inode) << 2;
		size = CRAMFS_24 (inode->size);
	}

	/* List the given directory */
	while (inodeoffset < size) {
		inode = (struct cramfs_inode *) (PART_OFFSET(info) + offset +
						 inodeoffset);

		nextoffset = cramfs_list_inode (info, offset + inodeoffset);
		if (nextoffset == 0)
			break;
		inodeoffset += sizeof (struct cramfs_inode) + nextoffset;
	}

	return 1;
}

int cramfs_info (struct part_info *info)
{
	if (cramfs_read_super (info))
		return 0;

	printf ("size: 0x%x (%u)\n", super.size, super.size);

	if (super.flags != 0) {
		printf ("flags:\n");
		if (super.flags & CRAMFS_FLAG_FSID_VERSION_2)
			printf ("\tFSID version 2\n");
		if (super.flags & CRAMFS_FLAG_SORTED_DIRS)
			printf ("\tsorted dirs\n");
		if (super.flags & CRAMFS_FLAG_HOLES)
			printf ("\tholes\n");
		if (super.flags & CRAMFS_FLAG_SHIFTED_ROOT_OFFSET)
			printf ("\tshifted root offset\n");
	}

	printf ("fsid:\n\tcrc: 0x%x\n\tedition: 0x%x\n",
		super.fsid.crc, super.fsid.edition);
	printf ("name: %16s\n", super.name);

	return 1;
}

int cramfs_check (struct part_info *info)
{
	struct cramfs_super *sb;

	if (info->dev->id->type != MTD_DEV_TYPE_NOR)
		return 0;

	sb = (struct cramfs_super *) PART_OFFSET(info);
	if (sb->magic != CRAMFS_32 (CRAMFS_MAGIC)) {
		/* check at 512 byte offset */
		sb = (struct cramfs_super *) (PART_OFFSET(info) + 512);
		if (sb->magic != CRAMFS_32 (CRAMFS_MAGIC))
			return 0;
	}
	return 1;
}
Commit	Line	Data
dd875c76 WD	1	/*
	2	* cramfs.c
	3	*
	4	* Copyright (C) 1999 Linus Torvalds
	5	*
	6	* Copyright (C) 2000-2002 Transmeta Corporation
	7	*
	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
	11	*
	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.
	15	*
	16	* Compressed ROM filesystem for Linux.
	17	*
	18	* TODO:
	19	* add support for resolving symbolic links
	20	*/
	21
	22	/*
	23	* These are the VFS interfaces to the compressed ROM filesystem.
	24	* The actual compression is based on zlib, see the other files.
	25	*/
	26
	27	#include <common.h>
	28	#include <malloc.h>
dd875c76 WD	29	#include <asm/byteorder.h>
dd875c76 WD	30	#include <linux/stat.h>
180d3f74	31	#include <jffs2/jffs2.h>
dd875c76	32	#include <jffs2/load_kernel.h>
180d3f74	33	#include <cramfs/cramfs_fs.h>
dd875c76 WD	34
	35	/* These two macros may change in future, to provide better st_ino
	36	semantics. */
	37	#define CRAMINO(x) (CRAMFS_GET_OFFSET(x) ? CRAMFS_GET_OFFSET(x)<<2 : 1)
	38	#define OFFSET(x) ((x)->i_ino)
	39
	40	struct cramfs_super super;
	41
700a0c64 WD	42	/* CPU address space offset calculation macro, struct part_info offset is
700a0c64 WD	43	* device address space offset, so we need to shift it by a device start address. */
e6f2e902	44	extern flash_info_t flash_info[];
700a0c64 WD	45	#define PART_OFFSET(x) (x->offset + flash_info[x->dev->id->num].start[0])
700a0c64 WD	46
dd875c76 WD	47	static int cramfs_read_super (struct part_info *info)
	48	{
	49	unsigned long root_offset;
	50
	51	/* Read the first block and get the superblock from it */
700a0c64	52	memcpy (&super, (void *) PART_OFFSET(info), sizeof (super));
dd875c76 WD	53
	54	/* Do sanity checks on the superblock */
	55	if (super.magic != CRAMFS_32 (CRAMFS_MAGIC)) {
	56	/* check at 512 byte offset */
700a0c64	57	memcpy (&super, (void *) PART_OFFSET(info) + 512, sizeof (super));
dd875c76 WD	58	if (super.magic != CRAMFS_32 (CRAMFS_MAGIC)) {
	59	printf ("cramfs: wrong magic\n");
	60	return -1;
	61	}
	62	}
	63
	64	/* flags is reused several times, so swab it once */
	65	super.flags = CRAMFS_32 (super.flags);
	66	super.size = CRAMFS_32 (super.size);
	67
	68	/* get feature flags first */
	69	if (super.flags & ~CRAMFS_SUPPORTED_FLAGS) {
	70	printf ("cramfs: unsupported filesystem features\n");
	71	return -1;
	72	}
	73
	74	/* Check that the root inode is in a sane state */
	75	if (!S_ISDIR (CRAMFS_16 (super.root.mode))) {
	76	printf ("cramfs: root is not a directory\n");
	77	return -1;
	78	}
	79	root_offset = CRAMFS_GET_OFFSET (&(super.root)) << 2;
	80	if (root_offset == 0) {
	81	printf ("cramfs: empty filesystem");
	82	} else if (!(super.flags & CRAMFS_FLAG_SHIFTED_ROOT_OFFSET) &&
	83	((root_offset != sizeof (struct cramfs_super)) &&
	84	(root_offset != 512 + sizeof (struct cramfs_super)))) {
	85	printf ("cramfs: bad root offset %lu\n", root_offset);
	86	return -1;
	87	}
	88
	89	return 0;
	90	}
	91
700a0c64	92	static unsigned long cramfs_resolve (unsigned long begin, unsigned long offset,
dd875c76 WD	93	unsigned long size, int raw,
	94	char *filename)
	95	{
	96	unsigned long inodeoffset = 0, nextoffset;
	97
	98	while (inodeoffset < size) {
	99	struct cramfs_inode *inode;
	100	char *name;
	101	int namelen;
	102
	103	inode = (struct cramfs_inode *) (begin + offset +
	104	inodeoffset);
	105
	106	/*
	107	* Namelengths on disk are shifted by two
	108	* and the name padded out to 4-byte boundaries
	109	* with zeroes.
	110	*/
	111	namelen = CRAMFS_GET_NAMELEN (inode) << 2;
	112	name = (char *) inode + sizeof (struct cramfs_inode);
	113
	114	nextoffset =
	115	inodeoffset + sizeof (struct cramfs_inode) + namelen;
	116
	117	for (;;) {
	118	if (!namelen)
	119	return -1;
	120	if (name[namelen - 1])
	121	break;
	122	namelen--;
	123	}
	124
	125	if (!strncmp (filename, name, namelen)) {
	126	char *p = strtok (NULL, "/");
	127
	128	if (raw && (p == NULL \|\| *p == '\0'))
	129	return offset + inodeoffset;
	130
	131	if (S_ISDIR (CRAMFS_16 (inode->mode))) {
	132	return cramfs_resolve (begin,
	133	CRAMFS_GET_OFFSET
	134	(inode) << 2,
	135	CRAMFS_24 (inode->
	136	size), raw,
	137	p);
	138	} else if (S_ISREG (CRAMFS_16 (inode->mode))) {
	139	return offset + inodeoffset;
	140	} else {
	141	printf ("%.s: unsupported file type (%x)\n",
	142	namelen, namelen, name,
	143	CRAMFS_16 (inode->mode));
	144	return 0;
	145	}
	146	}
	147
	148	inodeoffset = nextoffset;
	149	}
	150
	151	printf ("can't find corresponding entry\n");
	152	return 0;
	153	}
	154
700a0c64	155	static int cramfs_uncompress (unsigned long begin, unsigned long offset,
dd875c76 WD	156	unsigned long loadoffset)
	157	{
	158	struct cramfs_inode inode = (struct cramfs_inode ) (begin + offset);
	159	unsigned long block_ptrs = (unsigned long )
	160	(begin + (CRAMFS_GET_OFFSET (inode) << 2));
	161	unsigned long curr_block = (CRAMFS_GET_OFFSET (inode) +
	162	(((CRAMFS_24 (inode->size)) +
	163	4095) >> 12)) << 2;
	164	int size, total_size = 0;
	165	int i;
	166
	167	cramfs_uncompress_init ();
	168
	169	for (i = 0; i < ((CRAMFS_24 (inode->size) + 4095) >> 12); i++) {
	170	size = cramfs_uncompress_block ((void *) loadoffset,
	171	(void *) (begin + curr_block),
	172	(CRAMFS_32 (block_ptrs[i]) -
	173	curr_block));
	174	if (size < 0)
	175	return size;
	176	loadoffset += size;
	177	total_size += size;
	178	curr_block = CRAMFS_32 (block_ptrs[i]);
	179	}
	180
	181	cramfs_uncompress_exit ();
	182	return total_size;
	183	}
	184
	185	int cramfs_load (char loadoffset, struct part_info info, char *filename)
	186	{
	187	unsigned long offset;
	188
	189	if (cramfs_read_super (info))
	190	return -1;
	191
700a0c64	192	offset = cramfs_resolve (PART_OFFSET(info),
dd875c76 WD	193	CRAMFS_GET_OFFSET (&(super.root)) << 2,
	194	CRAMFS_24 (super.root.size), 0,
	195	strtok (filename, "/"));
	196
	197	if (offset <= 0)
	198	return offset;
	199
700a0c64	200	return cramfs_uncompress (PART_OFFSET(info), offset,
dd875c76 WD	201	(unsigned long) loadoffset);
	202	}
	203
dd875c76 WD	204	static int cramfs_list_inode (struct part_info *info, unsigned long offset)
	205	{
	206	struct cramfs_inode inode = (struct cramfs_inode )
700a0c64	207	(PART_OFFSET(info) + offset);
dd875c76 WD	208	char *name, str[20];
	209	int namelen, nextoff;
	210
	211	/*
	212	* Namelengths on disk are shifted by two
	213	* and the name padded out to 4-byte boundaries
	214	* with zeroes.
	215	*/
	216	namelen = CRAMFS_GET_NAMELEN (inode) << 2;
	217	name = (char *) inode + sizeof (struct cramfs_inode);
	218	nextoff = namelen;
	219
	220	for (;;) {
	221	if (!namelen)
	222	return namelen;
	223	if (name[namelen - 1])
	224	break;
	225	namelen--;
	226	}
	227
	228	printf (" %s %8d %.s", mkmodestr (CRAMFS_16 (inode->mode), str),
	229	CRAMFS_24 (inode->size), namelen, namelen, name);
	230
	231	if ((CRAMFS_16 (inode->mode) & S_IFMT) == S_IFLNK) {
	232	/* symbolic link.
	233	* Unpack the link target, trusting in the inode's size field.
	234	*/
	235	unsigned long size = CRAMFS_24 (inode->size);
	236	char *link = malloc (size);
	237
700a0c64	238	if (link != NULL && cramfs_uncompress (PART_OFFSET(info), offset,
dd875c76 WD	239	(unsigned long) link)
	240	== size)
	241	printf (" -> %.s\n", (int) size, (int) size, link);
	242	else
	243	printf (" [Error reading link]\n");
	244	if (link)
	245	free (link);
	246	} else
	247	printf ("\n");
	248
	249	return nextoff;
	250	}
	251
	252	int cramfs_ls (struct part_info info, char filename)
	253	{
	254	struct cramfs_inode *inode;
	255	unsigned long inodeoffset = 0, nextoffset;
	256	unsigned long offset, size;
	257
	258	if (cramfs_read_super (info))
	259	return -1;
	260
	261	if (strlen (filename) == 0 \|\| !strcmp (filename, "/")) {
	262	/* Root directory. Use root inode in super block */
	263	offset = CRAMFS_GET_OFFSET (&(super.root)) << 2;
	264	size = CRAMFS_24 (super.root.size);
	265	} else {
	266	/* Resolve the path */
700a0c64	267	offset = cramfs_resolve (PART_OFFSET(info),
dd875c76 WD	268	CRAMFS_GET_OFFSET (&(super.root)) <<
	269	2, CRAMFS_24 (super.root.size), 1,
	270	strtok (filename, "/"));
	271
	272	if (offset <= 0)
	273	return offset;
	274
	275	/* Resolving was successful. Examine the inode */
700a0c64	276	inode = (struct cramfs_inode *) (PART_OFFSET(info) + offset);
dd875c76 WD	277	if (!S_ISDIR (CRAMFS_16 (inode->mode))) {
	278	/* It's not a directory - list it, and that's that */
	279	return (cramfs_list_inode (info, offset) > 0);
	280	}
	281
	282	/* It's a directory. List files within */
	283	offset = CRAMFS_GET_OFFSET (inode) << 2;
	284	size = CRAMFS_24 (inode->size);
	285	}
	286
	287	/* List the given directory */
	288	while (inodeoffset < size) {
700a0c64	289	inode = (struct cramfs_inode *) (PART_OFFSET(info) + offset +
dd875c76 WD	290	inodeoffset);
	291
	292	nextoffset = cramfs_list_inode (info, offset + inodeoffset);
	293	if (nextoffset == 0)
	294	break;
	295	inodeoffset += sizeof (struct cramfs_inode) + nextoffset;
	296	}
	297
	298	return 1;
	299	}
	300
	301	int cramfs_info (struct part_info *info)
	302	{
	303	if (cramfs_read_super (info))
	304	return 0;
	305
	306	printf ("size: 0x%x (%u)\n", super.size, super.size);
	307
	308	if (super.flags != 0) {
	309	printf ("flags:\n");
	310	if (super.flags & CRAMFS_FLAG_FSID_VERSION_2)
	311	printf ("\tFSID version 2\n");
	312	if (super.flags & CRAMFS_FLAG_SORTED_DIRS)
	313	printf ("\tsorted dirs\n");
	314	if (super.flags & CRAMFS_FLAG_HOLES)
	315	printf ("\tholes\n");
	316	if (super.flags & CRAMFS_FLAG_SHIFTED_ROOT_OFFSET)
	317	printf ("\tshifted root offset\n");
	318	}
	319
	320	printf ("fsid:\n\tcrc: 0x%x\n\tedition: 0x%x\n",
	321	super.fsid.crc, super.fsid.edition);
	322	printf ("name: %16s\n", super.name);
	323
	324	return 1;
	325	}
	326
	327	int cramfs_check (struct part_info *info)
	328	{
700a0c64 WD	329	struct cramfs_super *sb;
	330
	331	if (info->dev->id->type != MTD_DEV_TYPE_NOR)
	332	return 0;
dd875c76	333
700a0c64	334	sb = (struct cramfs_super *) PART_OFFSET(info);
dd875c76 WD	335	if (sb->magic != CRAMFS_32 (CRAMFS_MAGIC)) {
dd875c76 WD	336	/* check at 512 byte offset */
700a0c64 WD	337	sb = (struct cramfs_super *) (PART_OFFSET(info) + 512);
700a0c64 WD	338	if (sb->magic != CRAMFS_32 (CRAMFS_MAGIC))
dd875c76	339	return 0;
dd875c76 WD	340	}
	341	return 1;
	342	}