[linux.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 <linux/slab.h>

#include "do_mounts.h"
#include "../fs/squashfs/squashfs_fs.h"

#include <linux/decompress/generic.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
 *	squashfs
 *	gzip
 */
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;
	struct squashfs_super_block *squashfsb;
	int nblocks = -1;
	unsigned char *buf;
	const char *compress_name;

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

	minixsb = (struct minix_super_block *) buf;
	ext2sb = (struct ext2_super_block *) buf;
	romfsb = (struct romfs_super_block *) buf;
	cramfsb = (struct cramfs_super *) buf;
	squashfsb = (struct squashfs_super_block *) 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);

	*decompressor = decompress_method(buf, size, &compress_name);
	if (compress_name) {
		printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n",
		       compress_name, start_block);
		if (!*decompressor)
			printk(KERN_EMERG
			       "RAMDISK: %s decompressor not configured!\n",
			       compress_name);
		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;
	}

	/* squashfs is at block zero too */
	if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) {
		printk(KERN_NOTICE
		       "RAMDISK: squashfs filesystem found at block %d\n",
		       start_block);
		nblocks = (le64_to_cpu(squashfsb->bytes_used) + 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((const char __user __force *) "/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((const char __user __force *) "/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>
5a0e3ad6	10	#include <linux/slab.h>
1da177e4 LT	11
1da177e4 LT	12	#include "do_mounts.h"
b8fed87d	13	#include "../fs/squashfs/squashfs_fs.h"
1da177e4	14
30d65dbf AK	15	#include <linux/decompress/generic.h>
30d65dbf AK	16
30d65dbf	17
1da177e4 LT	18	int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */
	19
	20	static int __init prompt_ramdisk(char *str)
	21	{
	22	rd_prompt = simple_strtol(str,NULL,0) & 1;
	23	return 1;
	24	}
	25	__setup("prompt_ramdisk=", prompt_ramdisk);
	26
	27	int __initdata rd_image_start; /* starting block # of image */
	28
	29	static int __init ramdisk_start_setup(char *str)
	30	{
	31	rd_image_start = simple_strtol(str,NULL,0);
	32	return 1;
	33	}
	34	__setup("ramdisk_start=", ramdisk_start_setup);
	35
30d65dbf	36	static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);
1da177e4 LT	37
	38	/*
	39	* This routine tries to find a RAM disk image to load, and returns the
	40	* number of blocks to read for a non-compressed image, 0 if the image
	41	* is a compressed image, and -1 if an image with the right magic
	42	* numbers could not be found.
	43	*
	44	* We currently check for the following magic numbers:
b172fd88 PA	45	* minix
b172fd88 PA	46	* ext2
1da177e4 LT	47	* romfs
1da177e4 LT	48	* cramfs
b8fed87d	49	* squashfs
b172fd88	50	* gzip
1da177e4	51	*/
b172fd88	52	static int __init
30d65dbf	53	identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor)
1da177e4 LT	54	{
	55	const int size = 512;
	56	struct minix_super_block *minixsb;
	57	struct ext2_super_block *ext2sb;
	58	struct romfs_super_block *romfsb;
	59	struct cramfs_super *cramfsb;
b8fed87d	60	struct squashfs_super_block *squashfsb;
1da177e4 LT	61	int nblocks = -1;
1da177e4 LT	62	unsigned char *buf;
889c92d2	63	const char *compress_name;
1da177e4 LT	64
1da177e4 LT	65	buf = kmalloc(size, GFP_KERNEL);
c80544dc	66	if (!buf)
ea611b26	67	return -ENOMEM;
1da177e4 LT	68
	69	minixsb = (struct minix_super_block *) buf;
	70	ext2sb = (struct ext2_super_block *) buf;
	71	romfsb = (struct romfs_super_block *) buf;
	72	cramfsb = (struct cramfs_super *) buf;
b8fed87d	73	squashfsb = (struct squashfs_super_block *) buf;
1da177e4 LT	74	memset(buf, 0xe5, size);
	75
	76	/*
b172fd88	77	* Read block 0 to test for compressed kernel
1da177e4 LT	78	*/
	79	sys_lseek(fd, start_block * BLOCK_SIZE, 0);
	80	sys_read(fd, buf, size);
	81
889c92d2	82	*decompressor = decompress_method(buf, size, &compress_name);
23a22d57	83	if (compress_name) {
889c92d2 PA	84	printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n",
889c92d2 PA	85	compress_name, start_block);
23a22d57	86	if (!*decompressor)
73310a16 PA	87	printk(KERN_EMERG
73310a16 PA	88	"RAMDISK: %s decompressor not configured!\n",
23a22d57	89	compress_name);
889c92d2 PA	90	nblocks = 0;
889c92d2 PA	91	goto done;
1da177e4 LT	92	}
	93
	94	/* romfs is at block zero too */
	95	if (romfsb->word0 == ROMSB_WORD0 &&
	96	romfsb->word1 == ROMSB_WORD1) {
	97	printk(KERN_NOTICE
	98	"RAMDISK: romfs filesystem found at block %d\n",
	99	start_block);
	100	nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
	101	goto done;
	102	}
	103
	104	if (cramfsb->magic == CRAMFS_MAGIC) {
	105	printk(KERN_NOTICE
	106	"RAMDISK: cramfs filesystem found at block %d\n",
	107	start_block);
	108	nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
	109	goto done;
	110	}
	111
b8fed87d PL	112	/* squashfs is at block zero too */
	113	if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) {
	114	printk(KERN_NOTICE
	115	"RAMDISK: squashfs filesystem found at block %d\n",
	116	start_block);
	117	nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1)
	118	>> BLOCK_SIZE_BITS;
	119	goto done;
	120	}
	121
1da177e4 LT	122	/*
	123	* Read block 1 to test for minix and ext2 superblock
	124	*/
	125	sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
	126	sys_read(fd, buf, size);
	127
	128	/* Try minix */
	129	if (minixsb->s_magic == MINIX_SUPER_MAGIC \|\|
	130	minixsb->s_magic == MINIX_SUPER_MAGIC2) {
	131	printk(KERN_NOTICE
	132	"RAMDISK: Minix filesystem found at block %d\n",
	133	start_block);
	134	nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
	135	goto done;
	136	}
	137
	138	/* Try ext2 */
	139	if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) {
	140	printk(KERN_NOTICE
	141	"RAMDISK: ext2 filesystem found at block %d\n",
	142	start_block);
	143	nblocks = le32_to_cpu(ext2sb->s_blocks_count) <<
	144	le32_to_cpu(ext2sb->s_log_block_size);
	145	goto done;
	146	}
	147
	148	printk(KERN_NOTICE
	149	"RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
	150	start_block);
b172fd88	151
1da177e4 LT	152	done:
	153	sys_lseek(fd, start_block * BLOCK_SIZE, 0);
	154	kfree(buf);
	155	return nblocks;
	156	}
	157
	158	int __init rd_load_image(char *from)
	159	{
	160	int res = 0;
	161	int in_fd, out_fd;
	162	unsigned long rd_blocks, devblocks;
	163	int nblocks, i, disk;
	164	char *buf = NULL;
	165	unsigned short rotate = 0;
30d65dbf	166	decompress_fn decompressor = NULL;
347a8dc3	167	#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
1da177e4 LT	168	char rotator[4] = { '\|' , '/' , '-' , '\\' };
	169	#endif
	170
562f5e63	171	out_fd = sys_open((const char __user __force *) "/dev/ram", O_RDWR, 0);
1da177e4 LT	172	if (out_fd < 0)
	173	goto out;
	174
	175	in_fd = sys_open(from, O_RDONLY, 0);
	176	if (in_fd < 0)
	177	goto noclose_input;
	178
30d65dbf	179	nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
1da177e4 LT	180	if (nblocks < 0)
	181	goto done;
	182
	183	if (nblocks == 0) {
30d65dbf	184	if (crd_load(in_fd, out_fd, decompressor) == 0)
1da177e4	185	goto successful_load;
1da177e4 LT	186	goto done;
	187	}
	188
	189	/*
	190	* NOTE NOTE: nblocks is not actually blocks but
	191	* the number of kibibytes of data to load into a ramdisk.
	192	* So any ramdisk block size that is a multiple of 1KiB should
	193	* work when the appropriate ramdisk_blocksize is specified
	194	* on the command line.
	195	*
	196	* The default ramdisk_blocksize is 1KiB and it is generally
	197	* silly to use anything else, so make sure to use 1KiB
	198	* blocksize while generating ext2fs ramdisk-images.
	199	*/
	200	if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
	201	rd_blocks = 0;
	202	else
	203	rd_blocks >>= 1;
	204
	205	if (nblocks > rd_blocks) {
	206	printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
	207	nblocks, rd_blocks);
	208	goto done;
	209	}
b172fd88	210
1da177e4 LT	211	/*
	212	* OK, time to copy in the data
	213	*/
	214	if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
	215	devblocks = 0;
	216	else
	217	devblocks >>= 1;
	218
	219	if (strcmp(from, "/initrd.image") == 0)
	220	devblocks = nblocks;
	221
	222	if (devblocks == 0) {
	223	printk(KERN_ERR "RAMDISK: could not determine device size\n");
	224	goto done;
	225	}
	226
	227	buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
d613c3e2	228	if (!buf) {
1da177e4 LT	229	printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
	230	goto done;
	231	}
	232
	233	printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
	234	nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
	235	for (i = 0, disk = 1; i < nblocks; i++) {
	236	if (i && (i % devblocks == 0)) {
	237	printk("done disk #%d.\n", disk++);
	238	rotate = 0;
	239	if (sys_close(in_fd)) {
	240	printk("Error closing the disk.\n");
	241	goto noclose_input;
	242	}
	243	change_floppy("disk #%d", disk);
	244	in_fd = sys_open(from, O_RDONLY, 0);
	245	if (in_fd < 0) {
	246	printk("Error opening disk.\n");
	247	goto noclose_input;
	248	}
	249	printk("Loading disk #%d... ", disk);
	250	}
	251	sys_read(in_fd, buf, BLOCK_SIZE);
	252	sys_write(out_fd, buf, BLOCK_SIZE);
347a8dc3	253	#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
1da177e4 LT	254	if (!(i % 16)) {
	255	printk("%c\b", rotator[rotate & 0x3]);
	256	rotate++;
	257	}
	258	#endif
	259	}
	260	printk("done.\n");
	261
	262	successful_load:
	263	res = 1;
	264	done:
	265	sys_close(in_fd);
	266	noclose_input:
	267	sys_close(out_fd);
	268	out:
	269	kfree(buf);
562f5e63	270	sys_unlink((const char __user __force *) "/dev/ram");
1da177e4 LT	271	return res;
	272	}
	273
	274	int __init rd_load_disk(int n)
	275	{
	276	if (rd_prompt)
	277	change_floppy("root floppy disk to be loaded into RAM disk");
bdaf8529 GKH	278	create_dev("/dev/root", ROOT_DEV);
bdaf8529 GKH	279	create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
1da177e4 LT	280	return rd_load_image("/dev/root");
	281	}
	282
1da177e4	283	static int exit_code;
30d65dbf	284	static int decompress_error;
1da177e4 LT	285	static int crd_infd, crd_outfd;
1da177e4 LT	286
30d65dbf	287	static int __init compr_fill(void *buf, unsigned int len)
1da177e4	288	{
30d65dbf AK	289	int r = sys_read(crd_infd, buf, len);
	290	if (r < 0)
	291	printk(KERN_ERR "RAMDISK: error while reading compressed data");
	292	else if (r == 0)
	293	printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
	294	return r;
1da177e4 LT	295	}
1da177e4 LT	296
30d65dbf	297	static int __init compr_flush(void *window, unsigned int outcnt)
1da177e4	298	{
30d65dbf AK	299	int written = sys_write(crd_outfd, window, outcnt);
	300	if (written != outcnt) {
	301	if (decompress_error == 0)
	302	printk(KERN_ERR
	303	"RAMDISK: incomplete write (%d != %d)\n",
	304	written, outcnt);
	305	decompress_error = 1;
	306	return -1;
	307	}
	308	return outcnt;
1da177e4 LT	309	}
	310
	311	static void __init error(char *x)
	312	{
	313	printk(KERN_ERR "%s\n", x);
	314	exit_code = 1;
30d65dbf	315	decompress_error = 1;
1da177e4 LT	316	}
1da177e4 LT	317
30d65dbf	318	static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
1da177e4 LT	319	{
1da177e4 LT	320	int result;
1da177e4 LT	321	crd_infd = in_fd;
1da177e4 LT	322	crd_outfd = out_fd;
30d65dbf AK	323	result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
30d65dbf AK	324	if (decompress_error)
1da177e4	325	result = 1;
1da177e4 LT	326	return result;
1da177e4 LT	327	}