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Diffstat (limited to 'kexec/arch/i386/kexec-bzImage.c')
-rw-r--r--kexec/arch/i386/kexec-bzImage.c471
1 files changed, 471 insertions, 0 deletions
diff --git a/kexec/arch/i386/kexec-bzImage.c b/kexec/arch/i386/kexec-bzImage.c
new file mode 100644
index 0000000..1b8f20c
--- /dev/null
+++ b/kexec/arch/i386/kexec-bzImage.c
@@ -0,0 +1,471 @@
+/*
+ * kexec: Linux boots Linux
+ *
+ * Copyright (C) 2003-2010 Eric Biederman (ebiederm@xmission.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <elf.h>
+#include <boot/elf_boot.h>
+#include <ip_checksum.h>
+#include <x86/x86-linux.h>
+#include "../../kexec.h"
+#include "../../kexec-elf.h"
+#include "../../kexec-syscall.h"
+#include "kexec-x86.h"
+#include "x86-linux-setup.h"
+#include "crashdump-x86.h"
+#include <arch/options.h>
+
+static const int probe_debug = 0;
+int bzImage_support_efi_boot = 0;
+
+int bzImage_probe(const char *buf, off_t len)
+{
+ const struct x86_linux_header *header;
+ if ((uintmax_t)len < (uintmax_t)(2 * 512)) {
+ if (probe_debug) {
+ fprintf(stderr, "File is too short to be a bzImage!\n");
+ }
+ return -1;
+ }
+ header = (const struct x86_linux_header *)buf;
+ if (memcmp(header->header_magic, "HdrS", 4) != 0) {
+ if (probe_debug) {
+ fprintf(stderr, "Not a bzImage\n");
+ }
+ return -1;
+ }
+ if (header->boot_sector_magic != 0xAA55) {
+ if (probe_debug) {
+ fprintf(stderr, "No x86 boot sector present\n");
+ }
+ /* No x86 boot sector present */
+ return -1;
+ }
+ if (header->protocol_version < 0x0200) {
+ if (probe_debug) {
+ fprintf(stderr, "Must be at least protocol version 2.00\n");
+ }
+ /* Must be at least protocol version 2.00 */
+ return -1;
+ }
+ if ((header->loadflags & 1) == 0) {
+ if (probe_debug) {
+ fprintf(stderr, "zImage not a bzImage\n");
+ }
+ /* Not a bzImage */
+ return -1;
+ }
+ /* I've got a bzImage */
+ if (probe_debug) {
+ fprintf(stderr, "It's a bzImage\n");
+ }
+ return 0;
+}
+
+
+void bzImage_usage(void)
+{
+ printf( " --real-mode Use the kernels real mode entry point.\n"
+ " --command-line=STRING Set the kernel command line to STRING.\n"
+ " --append=STRING Set the kernel command line to STRING.\n"
+ " --reuse-cmdline Use kernel command line from running system.\n"
+ " --initrd=FILE Use FILE as the kernel's initial ramdisk.\n"
+ " --ramdisk=FILE Use FILE as the kernel's initial ramdisk.\n"
+ " --dtb=FILE Use FILE as devicetree.\n"
+ );
+
+}
+
+int do_bzImage_load(struct kexec_info *info,
+ const char *kernel, off_t kernel_len,
+ const char *command_line, off_t command_line_len,
+ const char *initrd, off_t initrd_len,
+ const char *dtb, off_t dtb_len,
+ int real_mode_entry)
+{
+ struct x86_linux_header setup_header;
+ struct x86_linux_param_header *real_mode;
+ int setup_sects;
+ size_t size;
+ int kern16_size;
+ unsigned long setup_base, setup_size;
+ struct entry32_regs regs32;
+ struct entry16_regs regs16;
+ unsigned int relocatable_kernel = 0;
+ unsigned long kernel32_load_addr;
+ char *modified_cmdline;
+ unsigned long cmdline_end;
+ unsigned long kern16_size_needed;
+ unsigned long heap_size = 0;
+
+ /*
+ * Find out about the file I am about to load.
+ */
+ if ((uintmax_t)kernel_len < (uintmax_t)(2 * 512)) {
+ return -1;
+ }
+ memcpy(&setup_header, kernel, sizeof(setup_header));
+ setup_sects = setup_header.setup_sects;
+ if (setup_sects == 0) {
+ setup_sects = 4;
+ }
+
+ kern16_size = (setup_sects +1) *512;
+ if (kernel_len < kern16_size) {
+ fprintf(stderr, "BzImage truncated?\n");
+ return -1;
+ }
+
+ if (setup_header.protocol_version >= 0x0206) {
+ if ((uintmax_t)command_line_len >
+ (uintmax_t)setup_header.cmdline_size) {
+ dbgprintf("Kernel command line too long for kernel!\n");
+ return -1;
+ }
+ } else {
+ if (command_line_len > 255) {
+ dbgprintf("WARNING: This kernel may only support 255 byte command lines\n");
+ }
+ }
+
+ if (setup_header.protocol_version >= 0x0205) {
+ relocatable_kernel = setup_header.relocatable_kernel;
+ dbgprintf("bzImage is relocatable\n");
+ }
+
+ /* Can't use bzImage for crash dump purposes with real mode entry */
+ if((info->kexec_flags & KEXEC_ON_CRASH) && real_mode_entry) {
+ fprintf(stderr, "Can't use bzImage for crash dump purposes"
+ " with real mode entry\n");
+ return -1;
+ }
+
+ if((info->kexec_flags & KEXEC_ON_CRASH) && !relocatable_kernel) {
+ fprintf(stderr, "BzImage is not relocatable. Can't be used"
+ " as capture kernel.\n");
+ return -1;
+ }
+
+ /* Need to append some command line parameters internally in case of
+ * taking crash dumps.
+ */
+ if (info->kexec_flags & (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)) {
+ modified_cmdline = xmalloc(COMMAND_LINE_SIZE);
+ memset((void *)modified_cmdline, 0, COMMAND_LINE_SIZE);
+ if (command_line) {
+ strncpy(modified_cmdline, command_line,
+ COMMAND_LINE_SIZE);
+ modified_cmdline[COMMAND_LINE_SIZE - 1] = '\0';
+ }
+
+ /* If panic kernel is being loaded, additional segments need
+ * to be created. load_crashdump_segments will take care of
+ * loading the segments as high in memory as possible, hence
+ * in turn as away as possible from kernel to avoid being
+ * stomped by the kernel.
+ */
+ if (load_crashdump_segments(info, modified_cmdline, -1, 0) < 0)
+ return -1;
+
+ /* Use new command line buffer */
+ command_line = modified_cmdline;
+ command_line_len = strlen(command_line) +1;
+ }
+
+ /* Load the trampoline. This must load at a higher address
+ * than the argument/parameter segment or the kernel will stomp
+ * it's gdt.
+ *
+ * x86_64 purgatory code has got relocations type R_X86_64_32S
+ * that means purgatory got to be loaded within first 2G otherwise
+ * overflow takes place while applying relocations.
+ */
+ if (!real_mode_entry && relocatable_kernel)
+ elf_rel_build_load(info, &info->rhdr, purgatory, purgatory_size,
+ 0x3000, 0x7fffffff, -1, 0);
+ else
+ elf_rel_build_load(info, &info->rhdr, purgatory, purgatory_size,
+ 0x3000, 640*1024, -1, 0);
+ dbgprintf("Loaded purgatory at addr 0x%lx\n", info->rhdr.rel_addr);
+
+ /* The argument/parameter segment */
+ if (real_mode_entry) {
+ /* need to include size for bss and heap etc */
+ if (setup_header.protocol_version >= 0x0201)
+ kern16_size_needed = setup_header.heap_end_ptr;
+ else
+ kern16_size_needed = kern16_size + 8192; /* bss */
+ if (kern16_size_needed < kern16_size)
+ kern16_size_needed = kern16_size;
+ if (kern16_size_needed > 0xfffc)
+ die("kern16_size_needed is more then 64k\n");
+ heap_size = 0xfffc - kern16_size_needed; /* less 64k */
+ heap_size = _ALIGN_DOWN(heap_size, 0x200);
+ kern16_size_needed += heap_size;
+ } else {
+ kern16_size_needed = kern16_size;
+ /* need to bigger than size of struct bootparams */
+ if (kern16_size_needed < 4096)
+ kern16_size_needed = 4096;
+ }
+ setup_size = kern16_size_needed + command_line_len +
+ PURGATORY_CMDLINE_SIZE;
+ real_mode = xmalloc(setup_size);
+ memset(real_mode, 0, setup_size);
+ if (!real_mode_entry) {
+ unsigned long setup_header_size = kernel[0x201] + 0x202 - 0x1f1;
+
+ /* only copy setup_header */
+ if (setup_header_size > 0x7f)
+ setup_header_size = 0x7f;
+ memcpy((unsigned char *)real_mode + 0x1f1, kernel + 0x1f1,
+ setup_header_size);
+ } else {
+ /* copy setup code and setup_header */
+ memcpy(real_mode, kernel, kern16_size);
+ }
+
+ if (info->kexec_flags & (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)) {
+ /* If using bzImage for capture kernel, then we will not be
+ * executing real mode code. setup segment can be loaded
+ * anywhere as we will be just reading command line.
+ */
+ setup_base = add_buffer(info, real_mode, setup_size, setup_size,
+ 16, 0x3000, -1, -1);
+ }
+ else if (real_mode->protocol_version >= 0x0200) {
+ /* Careful setup_base must be greater than 8K */
+ setup_base = add_buffer(info, real_mode, setup_size, setup_size,
+ 16, 0x3000, 640*1024, 1);
+ } else {
+ add_segment(info, real_mode, setup_size, SETUP_BASE, setup_size);
+ setup_base = SETUP_BASE;
+ }
+ dbgprintf("Loaded real-mode code and command line at 0x%lx\n",
+ setup_base);
+
+ /* Verify purgatory loads higher than the parameters */
+ if (info->rhdr.rel_addr < setup_base) {
+ die("Could not put setup code above the kernel parameters\n");
+ }
+
+ /* The main kernel segment */
+ size = kernel_len - kern16_size;
+
+ if (real_mode->protocol_version >=0x0205 && relocatable_kernel) {
+ /* Relocatable bzImage */
+ unsigned long kern_align = real_mode->kernel_alignment;
+ unsigned long kernel32_max_addr = DEFAULT_BZIMAGE_ADDR_MAX;
+
+ if (kernel32_max_addr > real_mode->initrd_addr_max)
+ kernel32_max_addr = real_mode->initrd_addr_max;
+
+ kernel32_load_addr = add_buffer(info, kernel + kern16_size,
+ size, size, kern_align,
+ 0x100000, kernel32_max_addr,
+ 1);
+ }
+ else {
+ kernel32_load_addr = KERN32_BASE;
+ add_segment(info, kernel + kern16_size, size,
+ kernel32_load_addr, size);
+ }
+
+ dbgprintf("Loaded 32bit kernel at 0x%lx\n", kernel32_load_addr);
+
+ /* Tell the kernel what is going on */
+ setup_linux_bootloader_parameters(info, real_mode, setup_base,
+ kern16_size_needed, command_line, command_line_len,
+ initrd, initrd_len);
+
+ if (real_mode_entry && real_mode->protocol_version >= 0x0201) {
+ real_mode->loader_flags |= 0x80; /* CAN_USE_HEAP */
+ real_mode->heap_end_ptr += heap_size - 0x200; /*stack*/
+ }
+
+ /* Get the initial register values */
+ if (real_mode_entry)
+ elf_rel_get_symbol(&info->rhdr, "entry16_regs",
+ &regs16, sizeof(regs16));
+
+ /*
+ * Initialize the 32bit start information.
+ */
+ regs32.eax = 0; /* unused */
+ regs32.ebx = 0; /* 0 == boot not AP processor start */
+ regs32.ecx = 0; /* unused */
+ regs32.edx = 0; /* unused */
+ regs32.esi = setup_base; /* kernel parameters */
+ regs32.edi = 0; /* unused */
+ regs32.esp = elf_rel_get_addr(&info->rhdr, "stack_end"); /* stack, unused */
+ regs32.ebp = 0; /* unused */
+ regs32.eip = kernel32_load_addr; /* kernel entry point */
+
+ /*
+ * Initialize the 16bit start information.
+ */
+ if (real_mode_entry) {
+ regs16.ds = regs16.es = regs16.fs = regs16.gs = setup_base >> 4;
+ regs16.cs = regs16.ds + 0x20;
+ regs16.ip = 0;
+ /* XXX: Documentation/i386/boot.txt says 'ss' must equal 'ds' */
+ regs16.ss = (elf_rel_get_addr(&info->rhdr, "stack_end") - 64*1024) >> 4;
+ /* XXX: Documentation/i386/boot.txt says 'sp' must equal heap_end */
+ regs16.esp = 0xFFFC;
+
+ printf("Starting the kernel in real mode\n");
+ regs32.eip = elf_rel_get_addr(&info->rhdr, "entry16");
+ real_mode->kernel_start = kernel32_load_addr;
+ }
+ if (real_mode_entry && kexec_debug) {
+ unsigned long entry16_debug, pre32, first32;
+ uint32_t old_first32;
+ /* Find the location of the symbols */
+ entry16_debug = elf_rel_get_addr(&info->rhdr, "entry16_debug");
+ pre32 = elf_rel_get_addr(&info->rhdr, "entry16_debug_pre32");
+ first32 = elf_rel_get_addr(&info->rhdr, "entry16_debug_first32");
+
+ /* Hook all of the linux kernel hooks */
+ real_mode->rmode_switch_cs = entry16_debug >> 4;
+ real_mode->rmode_switch_ip = pre32 - entry16_debug;
+ old_first32 = real_mode->kernel_start;
+ real_mode->kernel_start = first32;
+ elf_rel_set_symbol(&info->rhdr, "entry16_debug_old_first32",
+ &old_first32, sizeof(old_first32));
+
+ regs32.eip = entry16_debug;
+ }
+ if (real_mode_entry) {
+ elf_rel_set_symbol(&info->rhdr, "entry16_regs",
+ &regs16, sizeof(regs16));
+ elf_rel_set_symbol(&info->rhdr, "entry16_debug_regs",
+ &regs16, sizeof(regs16));
+ }
+ elf_rel_set_symbol(&info->rhdr, "entry32_regs", &regs32, sizeof(regs32));
+ cmdline_end = setup_base + kern16_size_needed + command_line_len - 1;
+ elf_rel_set_symbol(&info->rhdr, "cmdline_end", &cmdline_end,
+ sizeof(unsigned long));
+
+ /* Fill in the information BIOS calls would normally provide. */
+ if (!real_mode_entry) {
+ setup_linux_system_parameters(info, real_mode);
+ }
+
+ if (dtb) {
+ setup_linux_dtb(info, real_mode, dtb, dtb_len);
+ }
+
+ return 0;
+}
+
+int bzImage_load(int argc, char **argv, const char *buf, off_t len,
+ struct kexec_info *info)
+{
+ char *command_line = NULL;
+ char *tmp_cmdline = NULL;
+ const char *ramdisk, *append = NULL, *dtb;
+ char *ramdisk_buf;
+ off_t ramdisk_length;
+ int command_line_len;
+ int real_mode_entry;
+ int opt;
+ int result;
+ char *dtb_buf;
+ off_t dtb_length;
+
+ /* See options.h -- add any more there, too. */
+ static const struct option options[] = {
+ KEXEC_ARCH_OPTIONS
+ { "command-line", 1, 0, OPT_APPEND },
+ { "append", 1, 0, OPT_APPEND },
+ { "reuse-cmdline", 0, 0, OPT_REUSE_CMDLINE },
+ { "initrd", 1, 0, OPT_RAMDISK },
+ { "ramdisk", 1, 0, OPT_RAMDISK },
+ { "real-mode", 0, 0, OPT_REAL_MODE },
+ { "dtb", 1, 0, OPT_DTB },
+ { 0, 0, 0, 0 },
+ };
+ static const char short_options[] = KEXEC_ARCH_OPT_STR "d";
+
+ real_mode_entry = 0;
+ ramdisk = 0;
+ ramdisk_length = 0;
+ dtb = 0;
+ dtb_length = 0;
+ while((opt = getopt_long(argc, argv, short_options, options, 0)) != -1) {
+ switch(opt) {
+ default:
+ /* Ignore core options */
+ if (opt < OPT_ARCH_MAX) {
+ break;
+ }
+ case OPT_APPEND:
+ append = optarg;
+ break;
+ case OPT_REUSE_CMDLINE:
+ tmp_cmdline = get_command_line();
+ break;
+ case OPT_RAMDISK:
+ ramdisk = optarg;
+ break;
+ case OPT_REAL_MODE:
+ real_mode_entry = 1;
+ break;
+ case OPT_DTB:
+ dtb = optarg;
+ break;
+ }
+ }
+ command_line = concat_cmdline(tmp_cmdline, append);
+ if (tmp_cmdline) {
+ free(tmp_cmdline);
+ }
+ command_line_len = 0;
+ if (command_line) {
+ command_line_len = strlen(command_line) +1;
+ } else {
+ command_line = strdup("\0");
+ command_line_len = 1;
+ }
+ ramdisk_buf = 0;
+ if (ramdisk) {
+ ramdisk_buf = slurp_file(ramdisk, &ramdisk_length);
+ }
+ dtb_buf = 0;
+ if (dtb) {
+ dtb_buf = slurp_file(dtb, &dtb_length);
+ }
+ result = do_bzImage_load(info,
+ buf, len,
+ command_line, command_line_len,
+ ramdisk_buf, ramdisk_length,
+ dtb_buf, dtb_length,
+ real_mode_entry);
+
+ free(command_line);
+ return result;
+}
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