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-rw-r--r--arch/ppc64/boot/addRamDisk.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/arch/ppc64/boot/addRamDisk.c b/arch/ppc64/boot/addRamDisk.c
new file mode 100644
index 000000000000..7f2c09473394
--- /dev/null
+++ b/arch/ppc64/boot/addRamDisk.c
@@ -0,0 +1,300 @@
+#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)
+{
+ fprintf(stderr, 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) {
+ fprintf(stderr, "Name of RAM disk file missing.\n");
+ exit(1);
+ }
+
+ if (argc < 3) {
+ fprintf(stderr, "Name of System Map input file is missing.\n");
+ exit(1);
+ }
+
+ if (argc < 4) {
+ fprintf(stderr, "Name of vmlinux file missing.\n");
+ exit(1);
+ }
+
+ if (argc < 5) {
+ fprintf(stderr, "Name of vmlinux output file missing.\n");
+ exit(1);
+ }
+
+
+ ramDisk = fopen(argv[1], "r");
+ if ( ! ramDisk ) {
+ fprintf(stderr, "RAM disk file \"%s\" failed to open.\n", argv[1]);
+ exit(1);
+ }
+
+ sysmap = fopen(argv[2], "r");
+ if ( ! sysmap ) {
+ fprintf(stderr, "System Map file \"%s\" failed to open.\n", argv[2]);
+ exit(1);
+ }
+
+ inputVmlinux = fopen(argv[3], "r");
+ if ( ! inputVmlinux ) {
+ fprintf(stderr, "vmlinux file \"%s\" failed to open.\n", argv[3]);
+ exit(1);
+ }
+
+ outputVmlinux = fopen(argv[4], "w+");
+ if ( ! outputVmlinux ) {
+ fprintf(stderr, "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 ) {
+ fprintf(stderr, "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;
+ /* read the whole file line by line, expect that it doesn't fail */
+ while ( fgets(inbuf, 4096, sysmap) ) ;
+ /* search for _end in the last page of the system map */
+ ptr_end = strstr(inbuf, " _end");
+ if (!ptr_end) {
+ fprintf(stderr, "Unable to find _end in the sysmap file \n");
+ fprintf(stderr, "inbuf: \n");
+ fprintf(stderr, "%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;
+}
+