[net-next-2.6.git] / arch / powerpc / boot / addRamDisk.c

#include <stdio.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <elf.h>

#define ElfHeaderSize  (64 * 1024)
#define ElfPages  (ElfHeaderSize / 4096)
#define KERNELBASE (0xc000000000000000)
#define _ALIGN_UP(addr,size)	(((addr)+((size)-1))&(~((size)-1)))

struct addr_range {
	unsigned long long addr;
	unsigned long memsize;
	unsigned long offset;
};

static int check_elf64(void *p, int size, struct addr_range *r)
{
	Elf64_Ehdr *elf64 = p;
	Elf64_Phdr *elf64ph;

	if (elf64->e_ident[EI_MAG0] != ELFMAG0 ||
	    elf64->e_ident[EI_MAG1] != ELFMAG1 ||
	    elf64->e_ident[EI_MAG2] != ELFMAG2 ||
	    elf64->e_ident[EI_MAG3] != ELFMAG3 ||
	    elf64->e_ident[EI_CLASS] != ELFCLASS64 ||
	    elf64->e_ident[EI_DATA] != ELFDATA2MSB ||
	    elf64->e_type != ET_EXEC || elf64->e_machine != EM_PPC64)
		return 0;

	if ((elf64->e_phoff + sizeof(Elf64_Phdr)) > size)
		return 0;

	elf64ph = (Elf64_Phdr *) ((unsigned long)elf64 +
				  (unsigned long)elf64->e_phoff);

	r->memsize = (unsigned long)elf64ph->p_memsz;
	r->offset = (unsigned long)elf64ph->p_offset;
	r->addr = (unsigned long long)elf64ph->p_vaddr;

#ifdef DEBUG
	printf("PPC64 ELF file, ph:\n");
	printf("p_type   0x%08x\n", elf64ph->p_type);
	printf("p_flags  0x%08x\n", elf64ph->p_flags);
	printf("p_offset 0x%016llx\n", elf64ph->p_offset);
	printf("p_vaddr  0x%016llx\n", elf64ph->p_vaddr);
	printf("p_paddr  0x%016llx\n", elf64ph->p_paddr);
	printf("p_filesz 0x%016llx\n", elf64ph->p_filesz);
	printf("p_memsz  0x%016llx\n", elf64ph->p_memsz);
	printf("p_align  0x%016llx\n", elf64ph->p_align);
	printf("... skipping 0x%08lx bytes of ELF header\n",
	       (unsigned long)elf64ph->p_offset);
#endif

	return 64;
}
static void get4k(FILE *file, char *buf )
{
	unsigned j;
	unsigned num = fread(buf, 1, 4096, file);
	for ( j=num; j<4096; ++j )
		buf[j] = 0;
}

static void put4k(FILE *file, char *buf )
{
	fwrite(buf, 1, 4096, file);
}

static void death(const char *msg, FILE *fdesc, const char *fname)
{
	fprintf(stderr, msg);
	fclose(fdesc);
	unlink(fname);
	exit(1);
}

int main(int argc, char **argv)
{
	char inbuf[4096];
	struct addr_range vmlinux;
	FILE *ramDisk;
	FILE *inputVmlinux;
	FILE *outputVmlinux;

	char *rd_name, *lx_name, *out_name;

	size_t i;
	unsigned long ramFileLen;
	unsigned long ramLen;
	unsigned long roundR;
	unsigned long offset_end;

	unsigned long kernelLen;
	unsigned long actualKernelLen;
	unsigned long round;
	unsigned long roundedKernelLen;
	unsigned long ramStartOffs;
	unsigned long ramPages;
	unsigned long roundedKernelPages;
	unsigned long hvReleaseData;
	u_int32_t eyeCatcher = 0xc8a5d9c4;
	unsigned long naca;
	unsigned long xRamDisk;
	unsigned long xRamDiskSize;
	long padPages;
  
  
	if (argc < 2) {
		fprintf(stderr, "Name of RAM disk file missing.\n");
		exit(1);
	}
	rd_name = argv[1];

	if (argc < 3) {
		fprintf(stderr, "Name of vmlinux file missing.\n");
		exit(1);
	}
	lx_name = argv[2];

	if (argc < 4) {
		fprintf(stderr, "Name of vmlinux output file missing.\n");
		exit(1);
	}
	out_name = argv[3];


	ramDisk = fopen(rd_name, "r");
	if ( ! ramDisk ) {
		fprintf(stderr, "RAM disk file \"%s\" failed to open.\n", rd_name);
		exit(1);
	}

	inputVmlinux = fopen(lx_name, "r");
	if ( ! inputVmlinux ) {
		fprintf(stderr, "vmlinux file \"%s\" failed to open.\n", lx_name);
		exit(1);
	}
  
	outputVmlinux = fopen(out_name, "w+");
	if ( ! outputVmlinux ) {
		fprintf(stderr, "output vmlinux file \"%s\" failed to open.\n", out_name);
		exit(1);
	}

	i = fread(inbuf, 1, sizeof(inbuf), inputVmlinux);
	if (i != sizeof(inbuf)) {
		fprintf(stderr, "can not read vmlinux file %s: %u\n", lx_name, i);
		exit(1);
	}

	i = check_elf64(inbuf, sizeof(inbuf), &vmlinux);
	if (i == 0) {
		fprintf(stderr, "You must have a linux kernel specified as argv[2]\n");
		exit(1);
	}

	/* Input Vmlinux file */
	fseek(inputVmlinux, 0, SEEK_END);
	kernelLen = ftell(inputVmlinux);
	fseek(inputVmlinux, 0, SEEK_SET);
	printf("kernel file size = %lu\n", kernelLen);

	actualKernelLen = kernelLen - ElfHeaderSize;

	printf("actual kernel length (minus ELF header) = %lu\n", actualKernelLen);

	round = actualKernelLen % 4096;
	roundedKernelLen = actualKernelLen;
	if ( round )
		roundedKernelLen += (4096 - round);
	printf("Vmlinux length rounded up to a 4k multiple = %ld/0x%lx \n", roundedKernelLen, roundedKernelLen);
	roundedKernelPages = roundedKernelLen / 4096;
	printf("Vmlinux pages to copy = %ld/0x%lx \n", roundedKernelPages, roundedKernelPages);

	offset_end = _ALIGN_UP(vmlinux.memsize, 4096);
	/* calc how many pages we need to insert between the vmlinux and the start of the ram disk */
	padPages = offset_end/4096 - roundedKernelPages;

	/* Check and see if the vmlinux is already larger than _end in System.map */
	if (padPages < 0) {
		/* vmlinux is larger than _end - adjust the offset to the start of the embedded ram disk */ 
		offset_end = roundedKernelLen;
		printf("vmlinux is larger than _end indicates it needs to be - offset_end = %lx \n", offset_end);
		padPages = 0;
		printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages);
	}
	else {
		/* _end is larger than vmlinux - use the offset to _end that we calculated from the system map */
		printf("vmlinux is smaller than _end indicates is needed - offset_end = %lx \n", offset_end);
		printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages);
	}


	/* Input Ram Disk file */
	// Set the offset that the ram disk will be started at.
	ramStartOffs = offset_end;  /* determined from the input vmlinux file and the system map */
	printf("Ram Disk will start at offset = 0x%lx \n", ramStartOffs);
  
	fseek(ramDisk, 0, SEEK_END);
	ramFileLen = ftell(ramDisk);
	fseek(ramDisk, 0, SEEK_SET);
	printf("%s file size = %ld/0x%lx \n", rd_name, ramFileLen, ramFileLen);

	ramLen = ramFileLen;

	roundR = 4096 - (ramLen % 4096);
	if ( roundR ) {
		printf("Rounding RAM disk file up to a multiple of 4096, adding %ld/0x%lx \n", roundR, roundR);
		ramLen += roundR;
	}

	printf("Rounded RAM disk size is %ld/0x%lx \n", ramLen, ramLen);
	ramPages = ramLen / 4096;
	printf("RAM disk pages to copy = %ld/0x%lx\n", ramPages, ramPages);


  // Copy 64K ELF header
	for (i=0; i<(ElfPages); ++i) {
		get4k( inputVmlinux, inbuf );
		put4k( outputVmlinux, inbuf );
	}

	/* Copy the vmlinux (as full pages). */
	fseek(inputVmlinux, ElfHeaderSize, SEEK_SET);
	for ( i=0; i<roundedKernelPages; ++i ) {
		get4k( inputVmlinux, inbuf );
		put4k( outputVmlinux, inbuf );
	}
  
	/* Insert pad pages (if appropriate) that are needed between */
	/* | the end of the vmlinux and the ram disk. */
	for (i=0; i<padPages; ++i) {
		memset(inbuf, 0, 4096);
		put4k(outputVmlinux, inbuf);
	}

	/* Copy the ram disk (as full pages). */
	for ( i=0; i<ramPages; ++i ) {
		get4k( ramDisk, inbuf );
		put4k( outputVmlinux, inbuf );
	}

	/* Close the input files */
	fclose(ramDisk);
	fclose(inputVmlinux);
	/* And flush the written output file */
	fflush(outputVmlinux);


	/* Fixup the new vmlinux to contain the ram disk starting offset (xRamDisk) and the ram disk size (xRamDiskSize) */
	/* fseek to the hvReleaseData pointer */
	fseek(outputVmlinux, ElfHeaderSize + 0x24, SEEK_SET);
	if (fread(&hvReleaseData, 4, 1, outputVmlinux) != 1) {
		death("Could not read hvReleaseData pointer\n", outputVmlinux, out_name);
	}
	hvReleaseData = ntohl(hvReleaseData); /* Convert to native int */
	printf("hvReleaseData is at %08lx\n", hvReleaseData);

	/* fseek to the hvReleaseData */
	fseek(outputVmlinux, ElfHeaderSize + hvReleaseData, SEEK_SET);
	if (fread(inbuf, 0x40, 1, outputVmlinux) != 1) {
		death("Could not read hvReleaseData\n", outputVmlinux, out_name);
	}
	/* Check hvReleaseData sanity */
	if (memcmp(inbuf, &eyeCatcher, 4) != 0) {
		death("hvReleaseData is invalid\n", outputVmlinux, out_name);
	}
	/* Get the naca pointer */
	naca = ntohl(*((u_int32_t*) &inbuf[0x0C])) - KERNELBASE;
	printf("Naca is at offset 0x%lx \n", naca);

	/* fseek to the naca */
	fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET);
	if (fread(inbuf, 0x18, 1, outputVmlinux) != 1) {
		death("Could not read naca\n", outputVmlinux, out_name);
	}
	xRamDisk = ntohl(*((u_int32_t *) &inbuf[0x0c]));
	xRamDiskSize = ntohl(*((u_int32_t *) &inbuf[0x14]));
	/* Make sure a RAM disk isn't already present */
	if ((xRamDisk != 0) || (xRamDiskSize != 0)) {
		death("RAM disk is already attached to this kernel\n", outputVmlinux, out_name);
	}
	/* Fill in the values */
	*((u_int32_t *) &inbuf[0x0c]) = htonl(ramStartOffs);
	*((u_int32_t *) &inbuf[0x14]) = htonl(ramPages);

	/* Write out the new naca */
	fflush(outputVmlinux);
	fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET);
	if (fwrite(inbuf, 0x18, 1, outputVmlinux) != 1) {
		death("Could not write naca\n", outputVmlinux, out_name);
	}
	printf("Ram Disk of 0x%lx pages is attached to the kernel at offset 0x%08lx\n",
	       ramPages, ramStartOffs);

	/* Done */
	fclose(outputVmlinux);
	/* Set permission to executable */
	chmod(out_name, S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);

	return 0;
}
Commit	Line	Data
1da177e4 LT	1	#include <stdio.h>
	2	#include <stdlib.h>
	3	#include <netinet/in.h>
	4	#include <unistd.h>
	5	#include <sys/types.h>
	6	#include <sys/stat.h>
	7	#include <string.h>
681c774d	8	#include <elf.h>
1da177e4 LT	9
	10	#define ElfHeaderSize (64 * 1024)
	11	#define ElfPages (ElfHeaderSize / 4096)
	12	#define KERNELBASE (0xc000000000000000)
681c774d	13	#define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1)))
1da177e4	14
681c774d OH	15	struct addr_range {
	16	unsigned long long addr;
	17	unsigned long memsize;
	18	unsigned long offset;
	19	};
	20
	21	static int check_elf64(void p, int size, struct addr_range r)
	22	{
	23	Elf64_Ehdr *elf64 = p;
	24	Elf64_Phdr *elf64ph;
	25
	26	if (elf64->e_ident[EI_MAG0] != ELFMAG0 \|\|
	27	elf64->e_ident[EI_MAG1] != ELFMAG1 \|\|
	28	elf64->e_ident[EI_MAG2] != ELFMAG2 \|\|
	29	elf64->e_ident[EI_MAG3] != ELFMAG3 \|\|
	30	elf64->e_ident[EI_CLASS] != ELFCLASS64 \|\|
	31	elf64->e_ident[EI_DATA] != ELFDATA2MSB \|\|
	32	elf64->e_type != ET_EXEC \|\| elf64->e_machine != EM_PPC64)
	33	return 0;
	34
	35	if ((elf64->e_phoff + sizeof(Elf64_Phdr)) > size)
	36	return 0;
	37
	38	elf64ph = (Elf64_Phdr *) ((unsigned long)elf64 +
	39	(unsigned long)elf64->e_phoff);
	40
	41	r->memsize = (unsigned long)elf64ph->p_memsz;
	42	r->offset = (unsigned long)elf64ph->p_offset;
	43	r->addr = (unsigned long long)elf64ph->p_vaddr;
	44
	45	#ifdef DEBUG
	46	printf("PPC64 ELF file, ph:\n");
	47	printf("p_type 0x%08x\n", elf64ph->p_type);
	48	printf("p_flags 0x%08x\n", elf64ph->p_flags);
	49	printf("p_offset 0x%016llx\n", elf64ph->p_offset);
	50	printf("p_vaddr 0x%016llx\n", elf64ph->p_vaddr);
	51	printf("p_paddr 0x%016llx\n", elf64ph->p_paddr);
	52	printf("p_filesz 0x%016llx\n", elf64ph->p_filesz);
	53	printf("p_memsz 0x%016llx\n", elf64ph->p_memsz);
	54	printf("p_align 0x%016llx\n", elf64ph->p_align);
	55	printf("... skipping 0x%08lx bytes of ELF header\n",
	56	(unsigned long)elf64ph->p_offset);
	57	#endif
	58
	59	return 64;
	60	}
95981e7d	61	static void get4k(FILE file, char buf )
1da177e4 LT	62	{
	63	unsigned j;
	64	unsigned num = fread(buf, 1, 4096, file);
	65	for ( j=num; j<4096; ++j )
	66	buf[j] = 0;
	67	}
	68
95981e7d	69	static void put4k(FILE file, char buf )
1da177e4 LT	70	{
	71	fwrite(buf, 1, 4096, file);
	72	}
	73
95981e7d	74	static void death(const char msg, FILE fdesc, const char *fname)
1da177e4 LT	75	{
	76	fprintf(stderr, msg);
	77	fclose(fdesc);
	78	unlink(fname);
	79	exit(1);
	80	}
	81
	82	int main(int argc, char **argv)
	83	{
	84	char inbuf[4096];
681c774d	85	struct addr_range vmlinux;
eba2fb2d	86	FILE *ramDisk;
eba2fb2d OH	87	FILE *inputVmlinux;
	88	FILE *outputVmlinux;
	89
58638bff	90	char rd_name, lx_name, *out_name;
681c774d OH	91
681c774d OH	92	size_t i;
eba2fb2d OH	93	unsigned long ramFileLen;
	94	unsigned long ramLen;
	95	unsigned long roundR;
eba2fb2d	96	unsigned long offset_end;
1da177e4	97
eba2fb2d OH	98	unsigned long kernelLen;
	99	unsigned long actualKernelLen;
	100	unsigned long round;
	101	unsigned long roundedKernelLen;
	102	unsigned long ramStartOffs;
	103	unsigned long ramPages;
	104	unsigned long roundedKernelPages;
	105	unsigned long hvReleaseData;
1da177e4	106	u_int32_t eyeCatcher = 0xc8a5d9c4;
eba2fb2d OH	107	unsigned long naca;
	108	unsigned long xRamDisk;
	109	unsigned long xRamDiskSize;
	110	long padPages;
1da177e4 LT	111
	112
	113	if (argc < 2) {
	114	fprintf(stderr, "Name of RAM disk file missing.\n");
	115	exit(1);
	116	}
681c774d	117	rd_name = argv[1];
1da177e4 LT	118
1da177e4 LT	119	if (argc < 3) {
1da177e4 LT	120	fprintf(stderr, "Name of vmlinux file missing.\n");
	121	exit(1);
	122	}
681c774d	123	lx_name = argv[2];
1da177e4	124
681c774d	125	if (argc < 4) {
1da177e4 LT	126	fprintf(stderr, "Name of vmlinux output file missing.\n");
	127	exit(1);
	128	}
681c774d	129	out_name = argv[3];
1da177e4 LT	130
1da177e4 LT	131
58638bff	132	ramDisk = fopen(rd_name, "r");
1da177e4	133	if ( ! ramDisk ) {
58638bff	134	fprintf(stderr, "RAM disk file \"%s\" failed to open.\n", rd_name);
1da177e4 LT	135	exit(1);
	136	}
	137
58638bff	138	inputVmlinux = fopen(lx_name, "r");
1da177e4	139	if ( ! inputVmlinux ) {
58638bff	140	fprintf(stderr, "vmlinux file \"%s\" failed to open.\n", lx_name);
1da177e4 LT	141	exit(1);
	142	}
	143
58638bff	144	outputVmlinux = fopen(out_name, "w+");
1da177e4	145	if ( ! outputVmlinux ) {
58638bff	146	fprintf(stderr, "output vmlinux file \"%s\" failed to open.\n", out_name);
1da177e4 LT	147	exit(1);
1da177e4 LT	148	}
681c774d OH	149
	150	i = fread(inbuf, 1, sizeof(inbuf), inputVmlinux);
	151	if (i != sizeof(inbuf)) {
	152	fprintf(stderr, "can not read vmlinux file %s: %u\n", lx_name, i);
	153	exit(1);
	154	}
	155
	156	i = check_elf64(inbuf, sizeof(inbuf), &vmlinux);
	157	if (i == 0) {
	158	fprintf(stderr, "You must have a linux kernel specified as argv[2]\n");
	159	exit(1);
	160	}
	161
1da177e4 LT	162	/* Input Vmlinux file */
	163	fseek(inputVmlinux, 0, SEEK_END);
	164	kernelLen = ftell(inputVmlinux);
	165	fseek(inputVmlinux, 0, SEEK_SET);
c44bc68d	166	printf("kernel file size = %lu\n", kernelLen);
1da177e4 LT	167
	168	actualKernelLen = kernelLen - ElfHeaderSize;
	169
c44bc68d	170	printf("actual kernel length (minus ELF header) = %lu\n", actualKernelLen);
1da177e4 LT	171
	172	round = actualKernelLen % 4096;
	173	roundedKernelLen = actualKernelLen;
	174	if ( round )
	175	roundedKernelLen += (4096 - round);
	176	printf("Vmlinux length rounded up to a 4k multiple = %ld/0x%lx \n", roundedKernelLen, roundedKernelLen);
	177	roundedKernelPages = roundedKernelLen / 4096;
	178	printf("Vmlinux pages to copy = %ld/0x%lx \n", roundedKernelPages, roundedKernelPages);
	179
681c774d	180	offset_end = _ALIGN_UP(vmlinux.memsize, 4096);
1da177e4 LT	181	/* calc how many pages we need to insert between the vmlinux and the start of the ram disk */
	182	padPages = offset_end/4096 - roundedKernelPages;
	183
	184	/* Check and see if the vmlinux is already larger than _end in System.map */
	185	if (padPages < 0) {
	186	/* vmlinux is larger than _end - adjust the offset to the start of the embedded ram disk */
	187	offset_end = roundedKernelLen;
	188	printf("vmlinux is larger than _end indicates it needs to be - offset_end = %lx \n", offset_end);
	189	padPages = 0;
	190	printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages);
	191	}
	192	else {
	193	/* _end is larger than vmlinux - use the offset to _end that we calculated from the system map */
	194	printf("vmlinux is smaller than _end indicates is needed - offset_end = %lx \n", offset_end);
	195	printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages);
	196	}
	197
	198
	199
	200	/* Input Ram Disk file */
	201	// Set the offset that the ram disk will be started at.
	202	ramStartOffs = offset_end; /* determined from the input vmlinux file and the system map */
	203	printf("Ram Disk will start at offset = 0x%lx \n", ramStartOffs);
	204
	205	fseek(ramDisk, 0, SEEK_END);
	206	ramFileLen = ftell(ramDisk);
	207	fseek(ramDisk, 0, SEEK_SET);
58638bff	208	printf("%s file size = %ld/0x%lx \n", rd_name, ramFileLen, ramFileLen);
1da177e4 LT	209
	210	ramLen = ramFileLen;
	211
	212	roundR = 4096 - (ramLen % 4096);
	213	if ( roundR ) {
	214	printf("Rounding RAM disk file up to a multiple of 4096, adding %ld/0x%lx \n", roundR, roundR);
	215	ramLen += roundR;
	216	}
	217
	218	printf("Rounded RAM disk size is %ld/0x%lx \n", ramLen, ramLen);
	219	ramPages = ramLen / 4096;
	220	printf("RAM disk pages to copy = %ld/0x%lx\n", ramPages, ramPages);
	221
	222
	223
	224	// Copy 64K ELF header
	225	for (i=0; i<(ElfPages); ++i) {
	226	get4k( inputVmlinux, inbuf );
	227	put4k( outputVmlinux, inbuf );
	228	}
	229
	230	/* Copy the vmlinux (as full pages). */
	231	fseek(inputVmlinux, ElfHeaderSize, SEEK_SET);
	232	for ( i=0; i<roundedKernelPages; ++i ) {
	233	get4k( inputVmlinux, inbuf );
	234	put4k( outputVmlinux, inbuf );
	235	}
	236
	237	/* Insert pad pages (if appropriate) that are needed between */
	238	/* \| the end of the vmlinux and the ram disk. */
	239	for (i=0; i<padPages; ++i) {
	240	memset(inbuf, 0, 4096);
	241	put4k(outputVmlinux, inbuf);
	242	}
	243
	244	/* Copy the ram disk (as full pages). */
	245	for ( i=0; i<ramPages; ++i ) {
	246	get4k( ramDisk, inbuf );
	247	put4k( outputVmlinux, inbuf );
	248	}
	249
	250	/* Close the input files */
	251	fclose(ramDisk);
	252	fclose(inputVmlinux);
	253	/* And flush the written output file */
	254	fflush(outputVmlinux);
	255
	256
	257
	258	/* Fixup the new vmlinux to contain the ram disk starting offset (xRamDisk) and the ram disk size (xRamDiskSize) */
	259	/* fseek to the hvReleaseData pointer */
	260	fseek(outputVmlinux, ElfHeaderSize + 0x24, SEEK_SET);
	261	if (fread(&hvReleaseData, 4, 1, outputVmlinux) != 1) {
58638bff	262	death("Could not read hvReleaseData pointer\n", outputVmlinux, out_name);
1da177e4 LT	263	}
1da177e4 LT	264	hvReleaseData = ntohl(hvReleaseData); /* Convert to native int */
c44bc68d	265	printf("hvReleaseData is at %08lx\n", hvReleaseData);
1da177e4 LT	266
	267	/* fseek to the hvReleaseData */
	268	fseek(outputVmlinux, ElfHeaderSize + hvReleaseData, SEEK_SET);
	269	if (fread(inbuf, 0x40, 1, outputVmlinux) != 1) {
58638bff	270	death("Could not read hvReleaseData\n", outputVmlinux, out_name);
1da177e4 LT	271	}
	272	/* Check hvReleaseData sanity */
	273	if (memcmp(inbuf, &eyeCatcher, 4) != 0) {
58638bff	274	death("hvReleaseData is invalid\n", outputVmlinux, out_name);
1da177e4 LT	275	}
	276	/* Get the naca pointer */
	277	naca = ntohl(((u_int32_t) &inbuf[0x0C])) - KERNELBASE;
	278	printf("Naca is at offset 0x%lx \n", naca);
	279
	280	/* fseek to the naca */
	281	fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET);
	282	if (fread(inbuf, 0x18, 1, outputVmlinux) != 1) {
58638bff	283	death("Could not read naca\n", outputVmlinux, out_name);
1da177e4 LT	284	}
	285	xRamDisk = ntohl(((u_int32_t ) &inbuf[0x0c]));
	286	xRamDiskSize = ntohl(((u_int32_t ) &inbuf[0x14]));
	287	/* Make sure a RAM disk isn't already present */
	288	if ((xRamDisk != 0) \|\| (xRamDiskSize != 0)) {
58638bff	289	death("RAM disk is already attached to this kernel\n", outputVmlinux, out_name);
1da177e4 LT	290	}
	291	/* Fill in the values */
	292	((u_int32_t ) &inbuf[0x0c]) = htonl(ramStartOffs);
	293	((u_int32_t ) &inbuf[0x14]) = htonl(ramPages);
	294
	295	/* Write out the new naca */
	296	fflush(outputVmlinux);
	297	fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET);
	298	if (fwrite(inbuf, 0x18, 1, outputVmlinux) != 1) {
58638bff	299	death("Could not write naca\n", outputVmlinux, out_name);
1da177e4	300	}
c44bc68d	301	printf("Ram Disk of 0x%lx pages is attached to the kernel at offset 0x%08lx\n",
1da177e4 LT	302	ramPages, ramStartOffs);
	303
	304	/* Done */
	305	fclose(outputVmlinux);
	306	/* Set permission to executable */
58638bff	307	chmod(out_name, S_IRUSR\|S_IWUSR\|S_IXUSR\|S_IRGRP\|S_IXGRP\|S_IROTH\|S_IXOTH);
1da177e4 LT	308
	309	return 0;
	310	}
	311