[net-next-2.6.git] / init / do_mounts_rd.c


#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/minix_fs.h>
#include <linux/ext2_fs.h>
#include <linux/romfs_fs.h>
#include <linux/cramfs_fs.h>
#include <linux/initrd.h>
#include <linux/string.h>

#include "do_mounts.h"

#include <linux/decompress/generic.h>

#include <linux/decompress/bunzip2.h>
#include <linux/decompress/unlzma.h>
#include <linux/decompress/inflate.h>

int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */

static int __init prompt_ramdisk(char *str)
{
	rd_prompt = simple_strtol(str,NULL,0) & 1;
	return 1;
}
__setup("prompt_ramdisk=", prompt_ramdisk);

int __initdata rd_image_start;		/* starting block # of image */

static int __init ramdisk_start_setup(char *str)
{
	rd_image_start = simple_strtol(str,NULL,0);
	return 1;
}
__setup("ramdisk_start=", ramdisk_start_setup);

static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);

/*
 * This routine tries to find a RAM disk image to load, and returns the
 * number of blocks to read for a non-compressed image, 0 if the image
 * is a compressed image, and -1 if an image with the right magic
 * numbers could not be found.
 *
 * We currently check for the following magic numbers:
 *	minix
 *	ext2
 *	romfs
 *	cramfs
 *	gzip
 */
static const struct compress_format {
	unsigned char magic[2];
	const char *name;
	decompress_fn decompressor;
} compressed_formats[] = {
#ifdef CONFIG_RD_GZIP
	{ {037, 0213}, "gzip", gunzip },
	{ {037, 0236}, "gzip", gunzip },
#endif
#ifdef CONFIG_RD_BZIP2
	{ {0x42, 0x5a}, "bzip2", bunzip2 },
#endif
#ifdef CONFIG_RD_LZMA
	{ {0x5d, 0x00}, "lzma", unlzma },
#endif
	{ {0, 0}, NULL, NULL }
};

static int __init
identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor)
{
	const int size = 512;
	struct minix_super_block *minixsb;
	struct ext2_super_block *ext2sb;
	struct romfs_super_block *romfsb;
	struct cramfs_super *cramfsb;
	int nblocks = -1;
	unsigned char *buf;
	const struct compress_format *cf;

	buf = kmalloc(size, GFP_KERNEL);
	if (!buf)
		return -1;

	minixsb = (struct minix_super_block *) buf;
	ext2sb = (struct ext2_super_block *) buf;
	romfsb = (struct romfs_super_block *) buf;
	cramfsb = (struct cramfs_super *) buf;
	memset(buf, 0xe5, size);

	/*
	 * Read block 0 to test for compressed kernel
	 */
	sys_lseek(fd, start_block * BLOCK_SIZE, 0);
	sys_read(fd, buf, size);

	for (cf = compressed_formats; cf->decompressor; cf++) {
		if (buf[0] == cf->magic[0] && buf[1] == cf->magic[1]) {
			printk(KERN_NOTICE
			       "RAMDISK: %s image found at block %d\n",
			       cf->name, start_block);
			*decompressor = cf->decompressor;
			nblocks = 0;
			goto done;
		}
	}

	/* romfs is at block zero too */
	if (romfsb->word0 == ROMSB_WORD0 &&
	    romfsb->word1 == ROMSB_WORD1) {
		printk(KERN_NOTICE
		       "RAMDISK: romfs filesystem found at block %d\n",
		       start_block);
		nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
		goto done;
	}

	if (cramfsb->magic == CRAMFS_MAGIC) {
		printk(KERN_NOTICE
		       "RAMDISK: cramfs filesystem found at block %d\n",
		       start_block);
		nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
		goto done;
	}

	/*
	 * Read block 1 to test for minix and ext2 superblock
	 */
	sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
	sys_read(fd, buf, size);

	/* Try minix */
	if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
	    minixsb->s_magic == MINIX_SUPER_MAGIC2) {
		printk(KERN_NOTICE
		       "RAMDISK: Minix filesystem found at block %d\n",
		       start_block);
		nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
		goto done;
	}

	/* Try ext2 */
	if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) {
		printk(KERN_NOTICE
		       "RAMDISK: ext2 filesystem found at block %d\n",
		       start_block);
		nblocks = le32_to_cpu(ext2sb->s_blocks_count) <<
			le32_to_cpu(ext2sb->s_log_block_size);
		goto done;
	}

	printk(KERN_NOTICE
	       "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
	       start_block);

done:
	sys_lseek(fd, start_block * BLOCK_SIZE, 0);
	kfree(buf);
	return nblocks;
}

int __init rd_load_image(char *from)
{
	int res = 0;
	int in_fd, out_fd;
	unsigned long rd_blocks, devblocks;
	int nblocks, i, disk;
	char *buf = NULL;
	unsigned short rotate = 0;
	decompress_fn decompressor = NULL;
#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
	char rotator[4] = { '|' , '/' , '-' , '\\' };
#endif

	out_fd = sys_open("/dev/ram", O_RDWR, 0);
	if (out_fd < 0)
		goto out;

	in_fd = sys_open(from, O_RDONLY, 0);
	if (in_fd < 0)
		goto noclose_input;

	nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
	if (nblocks < 0)
		goto done;

	if (nblocks == 0) {
		if (crd_load(in_fd, out_fd, decompressor) == 0)
			goto successful_load;
		goto done;
	}

	/*
	 * NOTE NOTE: nblocks is not actually blocks but
	 * the number of kibibytes of data to load into a ramdisk.
	 * So any ramdisk block size that is a multiple of 1KiB should
	 * work when the appropriate ramdisk_blocksize is specified
	 * on the command line.
	 *
	 * The default ramdisk_blocksize is 1KiB and it is generally
	 * silly to use anything else, so make sure to use 1KiB
	 * blocksize while generating ext2fs ramdisk-images.
	 */
	if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
		rd_blocks = 0;
	else
		rd_blocks >>= 1;

	if (nblocks > rd_blocks) {
		printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
		       nblocks, rd_blocks);
		goto done;
	}

	/*
	 * OK, time to copy in the data
	 */
	if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
		devblocks = 0;
	else
		devblocks >>= 1;

	if (strcmp(from, "/initrd.image") == 0)
		devblocks = nblocks;

	if (devblocks == 0) {
		printk(KERN_ERR "RAMDISK: could not determine device size\n");
		goto done;
	}

	buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
	if (!buf) {
		printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
		goto done;
	}

	printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
		nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
	for (i = 0, disk = 1; i < nblocks; i++) {
		if (i && (i % devblocks == 0)) {
			printk("done disk #%d.\n", disk++);
			rotate = 0;
			if (sys_close(in_fd)) {
				printk("Error closing the disk.\n");
				goto noclose_input;
			}
			change_floppy("disk #%d", disk);
			in_fd = sys_open(from, O_RDONLY, 0);
			if (in_fd < 0)  {
				printk("Error opening disk.\n");
				goto noclose_input;
			}
			printk("Loading disk #%d... ", disk);
		}
		sys_read(in_fd, buf, BLOCK_SIZE);
		sys_write(out_fd, buf, BLOCK_SIZE);
#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
		if (!(i % 16)) {
			printk("%c\b", rotator[rotate & 0x3]);
			rotate++;
		}
#endif
	}
	printk("done.\n");

successful_load:
	res = 1;
done:
	sys_close(in_fd);
noclose_input:
	sys_close(out_fd);
out:
	kfree(buf);
	sys_unlink("/dev/ram");
	return res;
}

int __init rd_load_disk(int n)
{
	if (rd_prompt)
		change_floppy("root floppy disk to be loaded into RAM disk");
	create_dev("/dev/root", ROOT_DEV);
	create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
	return rd_load_image("/dev/root");
}

static int exit_code;
static int decompress_error;
static int crd_infd, crd_outfd;

static int __init compr_fill(void *buf, unsigned int len)
{
	int r = sys_read(crd_infd, buf, len);
	if (r < 0)
		printk(KERN_ERR "RAMDISK: error while reading compressed data");
	else if (r == 0)
		printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
	return r;
}

static int __init compr_flush(void *window, unsigned int outcnt)
{
	int written = sys_write(crd_outfd, window, outcnt);
	if (written != outcnt) {
		if (decompress_error == 0)
			printk(KERN_ERR
			       "RAMDISK: incomplete write (%d != %d)\n",
			       written, outcnt);
		decompress_error = 1;
		return -1;
	}
	return outcnt;
}

static void __init error(char *x)
{
	printk(KERN_ERR "%s\n", x);
	exit_code = 1;
	decompress_error = 1;
}

static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
{
	int result;
	crd_infd = in_fd;
	crd_outfd = out_fd;
	result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
	if (decompress_error)
		result = 1;
	return result;
}
Commit	Line	Data
1da177e4 LT	1
	2	#include <linux/kernel.h>
	3	#include <linux/fs.h>
	4	#include <linux/minix_fs.h>
	5	#include <linux/ext2_fs.h>
	6	#include <linux/romfs_fs.h>
	7	#include <linux/cramfs_fs.h>
	8	#include <linux/initrd.h>
	9	#include <linux/string.h>
	10
	11	#include "do_mounts.h"
	12
30d65dbf AK	13	#include <linux/decompress/generic.h>
	14
	15	#include <linux/decompress/bunzip2.h>
	16	#include <linux/decompress/unlzma.h>
	17	#include <linux/decompress/inflate.h>
	18
1da177e4 LT	19	int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */
	20
	21	static int __init prompt_ramdisk(char *str)
	22	{
	23	rd_prompt = simple_strtol(str,NULL,0) & 1;
	24	return 1;
	25	}
	26	__setup("prompt_ramdisk=", prompt_ramdisk);
	27
	28	int __initdata rd_image_start; /* starting block # of image */
	29
	30	static int __init ramdisk_start_setup(char *str)
	31	{
	32	rd_image_start = simple_strtol(str,NULL,0);
	33	return 1;
	34	}
	35	__setup("ramdisk_start=", ramdisk_start_setup);
	36
30d65dbf	37	static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);
1da177e4 LT	38
	39	/*
	40	* This routine tries to find a RAM disk image to load, and returns the
	41	* number of blocks to read for a non-compressed image, 0 if the image
	42	* is a compressed image, and -1 if an image with the right magic
	43	* numbers could not be found.
	44	*
	45	* We currently check for the following magic numbers:
b172fd88 PA	46	* minix
b172fd88 PA	47	* ext2
1da177e4 LT	48	* romfs
1da177e4 LT	49	* cramfs
b172fd88	50	* gzip
1da177e4	51	*/
b172fd88 PA	52	static const struct compress_format {
	53	unsigned char magic[2];
	54	const char *name;
	55	decompress_fn decompressor;
	56	} compressed_formats[] = {
	57	#ifdef CONFIG_RD_GZIP
	58	{ {037, 0213}, "gzip", gunzip },
	59	{ {037, 0236}, "gzip", gunzip },
	60	#endif
	61	#ifdef CONFIG_RD_BZIP2
	62	{ {0x42, 0x5a}, "bzip2", bunzip2 },
	63	#endif
	64	#ifdef CONFIG_RD_LZMA
	65	{ {0x5d, 0x00}, "lzma", unlzma },
	66	#endif
	67	{ {0, 0}, NULL, NULL }
	68	};
	69
	70	static int __init
30d65dbf	71	identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor)
1da177e4 LT	72	{
	73	const int size = 512;
	74	struct minix_super_block *minixsb;
	75	struct ext2_super_block *ext2sb;
	76	struct romfs_super_block *romfsb;
	77	struct cramfs_super *cramfsb;
	78	int nblocks = -1;
	79	unsigned char *buf;
b172fd88	80	const struct compress_format *cf;
1da177e4 LT	81
1da177e4 LT	82	buf = kmalloc(size, GFP_KERNEL);
c80544dc	83	if (!buf)
1da177e4 LT	84	return -1;
	85
	86	minixsb = (struct minix_super_block *) buf;
	87	ext2sb = (struct ext2_super_block *) buf;
	88	romfsb = (struct romfs_super_block *) buf;
	89	cramfsb = (struct cramfs_super *) buf;
	90	memset(buf, 0xe5, size);
	91
	92	/*
b172fd88	93	* Read block 0 to test for compressed kernel
1da177e4 LT	94	*/
	95	sys_lseek(fd, start_block * BLOCK_SIZE, 0);
	96	sys_read(fd, buf, size);
	97
b172fd88 PA	98	for (cf = compressed_formats; cf->decompressor; cf++) {
	99	if (buf[0] == cf->magic[0] && buf[1] == cf->magic[1]) {
	100	printk(KERN_NOTICE
	101	"RAMDISK: %s image found at block %d\n",
	102	cf->name, start_block);
	103	*decompressor = cf->decompressor;
	104	nblocks = 0;
	105	goto done;
	106	}
1da177e4 LT	107	}
	108
	109	/* romfs is at block zero too */
	110	if (romfsb->word0 == ROMSB_WORD0 &&
	111	romfsb->word1 == ROMSB_WORD1) {
	112	printk(KERN_NOTICE
	113	"RAMDISK: romfs filesystem found at block %d\n",
	114	start_block);
	115	nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
	116	goto done;
	117	}
	118
	119	if (cramfsb->magic == CRAMFS_MAGIC) {
	120	printk(KERN_NOTICE
	121	"RAMDISK: cramfs filesystem found at block %d\n",
	122	start_block);
	123	nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
	124	goto done;
	125	}
	126
	127	/*
	128	* Read block 1 to test for minix and ext2 superblock
	129	*/
	130	sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
	131	sys_read(fd, buf, size);
	132
	133	/* Try minix */
	134	if (minixsb->s_magic == MINIX_SUPER_MAGIC \|\|
	135	minixsb->s_magic == MINIX_SUPER_MAGIC2) {
	136	printk(KERN_NOTICE
	137	"RAMDISK: Minix filesystem found at block %d\n",
	138	start_block);
	139	nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
	140	goto done;
	141	}
	142
	143	/* Try ext2 */
	144	if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) {
	145	printk(KERN_NOTICE
	146	"RAMDISK: ext2 filesystem found at block %d\n",
	147	start_block);
	148	nblocks = le32_to_cpu(ext2sb->s_blocks_count) <<
	149	le32_to_cpu(ext2sb->s_log_block_size);
	150	goto done;
	151	}
	152
	153	printk(KERN_NOTICE
	154	"RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
	155	start_block);
b172fd88	156
1da177e4 LT	157	done:
	158	sys_lseek(fd, start_block * BLOCK_SIZE, 0);
	159	kfree(buf);
	160	return nblocks;
	161	}
	162
	163	int __init rd_load_image(char *from)
	164	{
	165	int res = 0;
	166	int in_fd, out_fd;
	167	unsigned long rd_blocks, devblocks;
	168	int nblocks, i, disk;
	169	char *buf = NULL;
	170	unsigned short rotate = 0;
30d65dbf	171	decompress_fn decompressor = NULL;
347a8dc3	172	#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
1da177e4 LT	173	char rotator[4] = { '\|' , '/' , '-' , '\\' };
	174	#endif
	175
	176	out_fd = sys_open("/dev/ram", O_RDWR, 0);
	177	if (out_fd < 0)
	178	goto out;
	179
	180	in_fd = sys_open(from, O_RDONLY, 0);
	181	if (in_fd < 0)
	182	goto noclose_input;
	183
30d65dbf	184	nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
1da177e4 LT	185	if (nblocks < 0)
	186	goto done;
	187
	188	if (nblocks == 0) {
30d65dbf	189	if (crd_load(in_fd, out_fd, decompressor) == 0)
1da177e4	190	goto successful_load;
1da177e4 LT	191	goto done;
	192	}
	193
	194	/*
	195	* NOTE NOTE: nblocks is not actually blocks but
	196	* the number of kibibytes of data to load into a ramdisk.
	197	* So any ramdisk block size that is a multiple of 1KiB should
	198	* work when the appropriate ramdisk_blocksize is specified
	199	* on the command line.
	200	*
	201	* The default ramdisk_blocksize is 1KiB and it is generally
	202	* silly to use anything else, so make sure to use 1KiB
	203	* blocksize while generating ext2fs ramdisk-images.
	204	*/
	205	if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
	206	rd_blocks = 0;
	207	else
	208	rd_blocks >>= 1;
	209
	210	if (nblocks > rd_blocks) {
	211	printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
	212	nblocks, rd_blocks);
	213	goto done;
	214	}
b172fd88	215
1da177e4 LT	216	/*
	217	* OK, time to copy in the data
	218	*/
	219	if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
	220	devblocks = 0;
	221	else
	222	devblocks >>= 1;
	223
	224	if (strcmp(from, "/initrd.image") == 0)
	225	devblocks = nblocks;
	226
	227	if (devblocks == 0) {
	228	printk(KERN_ERR "RAMDISK: could not determine device size\n");
	229	goto done;
	230	}
	231
	232	buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
d613c3e2	233	if (!buf) {
1da177e4 LT	234	printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
	235	goto done;
	236	}
	237
	238	printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
	239	nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
	240	for (i = 0, disk = 1; i < nblocks; i++) {
	241	if (i && (i % devblocks == 0)) {
	242	printk("done disk #%d.\n", disk++);
	243	rotate = 0;
	244	if (sys_close(in_fd)) {
	245	printk("Error closing the disk.\n");
	246	goto noclose_input;
	247	}
	248	change_floppy("disk #%d", disk);
	249	in_fd = sys_open(from, O_RDONLY, 0);
	250	if (in_fd < 0) {
	251	printk("Error opening disk.\n");
	252	goto noclose_input;
	253	}
	254	printk("Loading disk #%d... ", disk);
	255	}
	256	sys_read(in_fd, buf, BLOCK_SIZE);
	257	sys_write(out_fd, buf, BLOCK_SIZE);
347a8dc3	258	#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
1da177e4 LT	259	if (!(i % 16)) {
	260	printk("%c\b", rotator[rotate & 0x3]);
	261	rotate++;
	262	}
	263	#endif
	264	}
	265	printk("done.\n");
	266
	267	successful_load:
	268	res = 1;
	269	done:
	270	sys_close(in_fd);
	271	noclose_input:
	272	sys_close(out_fd);
	273	out:
	274	kfree(buf);
	275	sys_unlink("/dev/ram");
	276	return res;
	277	}
	278
	279	int __init rd_load_disk(int n)
	280	{
	281	if (rd_prompt)
	282	change_floppy("root floppy disk to be loaded into RAM disk");
bdaf8529 GKH	283	create_dev("/dev/root", ROOT_DEV);
bdaf8529 GKH	284	create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
1da177e4 LT	285	return rd_load_image("/dev/root");
	286	}
	287
1da177e4	288	static int exit_code;
30d65dbf	289	static int decompress_error;
1da177e4 LT	290	static int crd_infd, crd_outfd;
1da177e4 LT	291
30d65dbf	292	static int __init compr_fill(void *buf, unsigned int len)
1da177e4	293	{
30d65dbf AK	294	int r = sys_read(crd_infd, buf, len);
	295	if (r < 0)
	296	printk(KERN_ERR "RAMDISK: error while reading compressed data");
	297	else if (r == 0)
	298	printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
	299	return r;
1da177e4 LT	300	}
1da177e4 LT	301
30d65dbf	302	static int __init compr_flush(void *window, unsigned int outcnt)
1da177e4	303	{
30d65dbf AK	304	int written = sys_write(crd_outfd, window, outcnt);
	305	if (written != outcnt) {
	306	if (decompress_error == 0)
	307	printk(KERN_ERR
	308	"RAMDISK: incomplete write (%d != %d)\n",
	309	written, outcnt);
	310	decompress_error = 1;
	311	return -1;
	312	}
	313	return outcnt;
1da177e4 LT	314	}
	315
	316	static void __init error(char *x)
	317	{
	318	printk(KERN_ERR "%s\n", x);
	319	exit_code = 1;
30d65dbf	320	decompress_error = 1;
1da177e4 LT	321	}
1da177e4 LT	322
30d65dbf	323	static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
1da177e4 LT	324	{
1da177e4 LT	325	int result;
1da177e4 LT	326	crd_infd = in_fd;
1da177e4 LT	327	crd_outfd = out_fd;
30d65dbf AK	328	result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
30d65dbf AK	329	if (decompress_error)
1da177e4	330	result = 1;
1da177e4 LT	331	return result;
1da177e4 LT	332	}