patch-2.4.19 linux-2.4.19/arch/ppc64/boot/addRamDisk.c

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diff -urN linux-2.4.18/arch/ppc64/boot/addRamDisk.c linux-2.4.19/arch/ppc64/boot/addRamDisk.c
@@ -0,0 +1,301 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <string.h>
+
+#define ElfHeaderSize  (64 * 1024)
+#define ElfPages  (ElfHeaderSize / 4096)
+#define KERNELBASE (0xc000000000000000)
+
+void get4k(FILE *file, char *buf )
+{
+	unsigned j;
+	unsigned num = fread(buf, 1, 4096, file);
+	for ( j=num; j<4096; ++j )
+		buf[j] = 0;
+}
+
+void put4k(FILE *file, char *buf )
+{
+	fwrite(buf, 1, 4096, file);
+}
+
+void death(const char *msg, FILE *fdesc, const char *fname) 
+{
+	printf(msg);
+	fclose(fdesc);
+	unlink(fname);
+	exit(1);
+}
+
+int main(int argc, char **argv)
+{
+	char inbuf[4096];
+	FILE *ramDisk = NULL;
+	FILE *sysmap = NULL;
+	FILE *inputVmlinux = NULL;
+	FILE *outputVmlinux = NULL;
+  
+	unsigned i = 0;
+	unsigned long ramFileLen = 0;
+	unsigned long ramLen = 0;
+	unsigned long roundR = 0;
+  
+	unsigned long sysmapFileLen = 0;
+	unsigned long sysmapLen = 0;
+	unsigned long sysmapPages = 0;
+	char* ptr_end = NULL; 
+	unsigned long offset_end = 0;
+
+	unsigned long kernelLen = 0;
+	unsigned long actualKernelLen = 0;
+	unsigned long round = 0;
+	unsigned long roundedKernelLen = 0;
+	unsigned long ramStartOffs = 0;
+	unsigned long ramPages = 0;
+	unsigned long roundedKernelPages = 0;
+	unsigned long hvReleaseData = 0;
+	u_int32_t eyeCatcher = 0xc8a5d9c4;
+	unsigned long naca = 0;
+	unsigned long xRamDisk = 0;
+	unsigned long xRamDiskSize = 0;
+	long padPages = 0;
+  
+  
+	if (argc < 2) {
+		printf("Name of RAM disk file missing.\n");
+		exit(1);
+	}
+
+	if (argc < 3) {
+		printf("Name of System Map input file is missing.\n");
+		exit(1);
+	}
+  
+	if (argc < 4) {
+		printf("Name of vmlinux file missing.\n");
+		exit(1);
+	}
+
+	if (argc < 5) {
+		printf("Name of vmlinux output file missing.\n");
+		exit(1);
+	}
+
+
+	ramDisk = fopen(argv[1], "r");
+	if ( ! ramDisk ) {
+		printf("RAM disk file \"%s\" failed to open.\n", argv[1]);
+		exit(1);
+	}
+
+	sysmap = fopen(argv[2], "r");
+	if ( ! sysmap ) {
+		printf("System Map file \"%s\" failed to open.\n", argv[2]);
+		exit(1);
+	}
+  
+	inputVmlinux = fopen(argv[3], "r");
+	if ( ! inputVmlinux ) {
+		printf("vmlinux file \"%s\" failed to open.\n", argv[3]);
+		exit(1);
+	}
+  
+	outputVmlinux = fopen(argv[4], "w+");
+	if ( ! outputVmlinux ) {
+		printf("output vmlinux file \"%s\" failed to open.\n", argv[4]);
+		exit(1);
+	}
+  
+  
+  
+	/* Input Vmlinux file */
+	fseek(inputVmlinux, 0, SEEK_END);
+	kernelLen = ftell(inputVmlinux);
+	fseek(inputVmlinux, 0, SEEK_SET);
+	printf("kernel file size = %d\n", kernelLen);
+	if ( kernelLen == 0 ) {
+		printf("You must have a linux kernel specified as argv[3]\n");
+		exit(1);
+	}
+
+	actualKernelLen = kernelLen - ElfHeaderSize;
+
+	printf("actual kernel length (minus ELF header) = %d\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);
+
+
+
+	/* Input System Map file */
+	/* (needs to be processed simply to determine if we need to add pad pages due to the static variables not being included in the vmlinux) */
+	fseek(sysmap, 0, SEEK_END);
+	sysmapFileLen = ftell(sysmap);
+	fseek(sysmap, 0, SEEK_SET);
+	printf("%s file size = %ld/0x%lx \n", argv[2], sysmapFileLen, sysmapFileLen);
+
+	sysmapLen = sysmapFileLen;
+
+	roundR = 4096 - (sysmapLen % 4096);
+	if (roundR) {
+		printf("Rounding System Map file up to a multiple of 4096, adding %ld/0x%lx \n", roundR, roundR);
+		sysmapLen += roundR;
+	}
+	printf("Rounded System Map size is %ld/0x%lx \n", sysmapLen, sysmapLen);
+  
+	/* Process the Sysmap file to determine where _end is */
+	sysmapPages = sysmapLen / 4096;
+	for (i=0; i<sysmapPages; ++i) {
+		get4k(sysmap, inbuf);
+	}
+	/* search for _end in the last page of the system map */
+	ptr_end = strstr(inbuf, " _end");
+	if (!ptr_end) {
+		printf("Unable to find _end in the sysmap file \n");
+		printf("inbuf: \n");
+		printf("%s \n", inbuf);
+		exit(1);
+	}
+	printf("Found _end in the last page of the sysmap - backing up 10 characters it looks like %s", ptr_end-10);
+	/* convert address of _end in system map to hex offset. */
+	offset_end = (unsigned int)strtol(ptr_end-10, NULL, 16);
+	/* 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", argv[1], 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, argv[4]);
+	}
+	hvReleaseData = ntohl(hvReleaseData); /* Convert to native int */
+	printf("hvReleaseData is at %08x\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, argv[4]);
+	}
+	/* Check hvReleaseData sanity */
+	if (memcmp(inbuf, &eyeCatcher, 4) != 0) {
+		death("hvReleaseData is invalid\n", outputVmlinux, argv[4]);
+	}
+	/* 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, argv[4]);
+	}
+	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, argv[4]);
+	}
+	/* 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, argv[4]);
+	}
+	printf("Ram Disk of 0x%lx pages is attached to the kernel at offset 0x%08x\n",
+	       ramPages, ramStartOffs);
+
+	/* Done */
+	fclose(outputVmlinux);
+	/* Set permission to executable */
+	chmod(argv[4], S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);
+
+	return 0;
+}
+

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TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)