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Diffstat (limited to 'arch/alpha/boot/tools/mkbb.c')
-rw-r--r--arch/alpha/boot/tools/mkbb.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/alpha/boot/tools/mkbb.c b/arch/alpha/boot/tools/mkbb.c
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+++ b/arch/alpha/boot/tools/mkbb.c
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+/* This utility makes a bootblock suitable for the SRM console/miniloader */
+
+/* Usage:
+ * mkbb <device> <lxboot>
+ *
+ * Where <device> is the name of the device to install the bootblock on,
+ * and <lxboot> is the name of a bootblock to merge in. This bootblock
+ * contains the offset and size of the bootloader. It must be exactly
+ * 512 bytes long.
+ */
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+
+/* Minimal definition of disklabel, so we don't have to include
+ * asm/disklabel.h (confuses make)
+ */
+#ifndef MAXPARTITIONS
+#define MAXPARTITIONS 8 /* max. # of partitions */
+#endif
+
+#ifndef u8
+#define u8 unsigned char
+#endif
+
+#ifndef u16
+#define u16 unsigned short
+#endif
+
+#ifndef u32
+#define u32 unsigned int
+#endif
+
+struct disklabel {
+ u32 d_magic; /* must be DISKLABELMAGIC */
+ u16 d_type, d_subtype;
+ u8 d_typename[16];
+ u8 d_packname[16];
+ u32 d_secsize;
+ u32 d_nsectors;
+ u32 d_ntracks;
+ u32 d_ncylinders;
+ u32 d_secpercyl;
+ u32 d_secprtunit;
+ u16 d_sparespertrack;
+ u16 d_sparespercyl;
+ u32 d_acylinders;
+ u16 d_rpm, d_interleave, d_trackskew, d_cylskew;
+ u32 d_headswitch, d_trkseek, d_flags;
+ u32 d_drivedata[5];
+ u32 d_spare[5];
+ u32 d_magic2; /* must be DISKLABELMAGIC */
+ u16 d_checksum;
+ u16 d_npartitions;
+ u32 d_bbsize, d_sbsize;
+ struct d_partition {
+ u32 p_size;
+ u32 p_offset;
+ u32 p_fsize;
+ u8 p_fstype;
+ u8 p_frag;
+ u16 p_cpg;
+ } d_partitions[MAXPARTITIONS];
+};
+
+
+typedef union __bootblock {
+ struct {
+ char __pad1[64];
+ struct disklabel __label;
+ } __u1;
+ struct {
+ unsigned long __pad2[63];
+ unsigned long __checksum;
+ } __u2;
+ char bootblock_bytes[512];
+ unsigned long bootblock_quadwords[64];
+} bootblock;
+
+#define bootblock_label __u1.__label
+#define bootblock_checksum __u2.__checksum
+
+main(int argc, char ** argv)
+{
+ bootblock bootblock_from_disk;
+ bootblock bootloader_image;
+ int dev, fd;
+ int i;
+ int nread;
+
+ /* Make sure of the arg count */
+ if(argc != 3) {
+ fprintf(stderr, "Usage: %s device lxboot\n", argv[0]);
+ exit(0);
+ }
+
+ /* First, open the device and make sure it's accessible */
+ dev = open(argv[1], O_RDWR);
+ if(dev < 0) {
+ perror(argv[1]);
+ exit(0);
+ }
+
+ /* Now open the lxboot and make sure it's reasonable */
+ fd = open(argv[2], O_RDONLY);
+ if(fd < 0) {
+ perror(argv[2]);
+ close(dev);
+ exit(0);
+ }
+
+ /* Read in the lxboot */
+ nread = read(fd, &bootloader_image, sizeof(bootblock));
+ if(nread != sizeof(bootblock)) {
+ perror("lxboot read");
+ fprintf(stderr, "expected %d, got %d\n", sizeof(bootblock), nread);
+ exit(0);
+ }
+
+ /* Read in the bootblock from disk. */
+ nread = read(dev, &bootblock_from_disk, sizeof(bootblock));
+ if(nread != sizeof(bootblock)) {
+ perror("bootblock read");
+ fprintf(stderr, "expected %d, got %d\n", sizeof(bootblock), nread);
+ exit(0);
+ }
+
+ /* Swap the bootblock's disklabel into the bootloader */
+ bootloader_image.bootblock_label = bootblock_from_disk.bootblock_label;
+
+ /* Calculate the bootblock checksum */
+ bootloader_image.bootblock_checksum = 0;
+ for(i = 0; i < 63; i++) {
+ bootloader_image.bootblock_checksum +=
+ bootloader_image.bootblock_quadwords[i];
+ }
+
+ /* Write the whole thing out! */
+ lseek(dev, 0L, SEEK_SET);
+ if(write(dev, &bootloader_image, sizeof(bootblock)) != sizeof(bootblock)) {
+ perror("bootblock write");
+ exit(0);
+ }
+
+ close(fd);
+ close(dev);
+ exit(0);
+}
+
+