diff options
Diffstat (limited to 'arch/ppc64/boot/addRamDisk.c')
-rw-r--r-- | arch/ppc64/boot/addRamDisk.c | 300 |
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 00000000000..7f2c0947339 --- /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; +} + |