diff options
Diffstat (limited to 'kexec/arch/i386/kexec-multiboot-x86.c')
-rw-r--r-- | kexec/arch/i386/kexec-multiboot-x86.c | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/kexec/arch/i386/kexec-multiboot-x86.c b/kexec/arch/i386/kexec-multiboot-x86.c new file mode 100644 index 0000000..33c885a --- /dev/null +++ b/kexec/arch/i386/kexec-multiboot-x86.c @@ -0,0 +1,505 @@ +/* + * kexec-multiboot-x86.c + * + * (partial) multiboot support for kexec. Only supports ELF32 + * kernels, and a subset of the multiboot info page options + * (i.e. enough to boot the Xen hypervisor). + * + * TODO: + * - smarter allocation of new segments + * - proper support for the MULTIBOOT_VIDEO_MODE bit + * + * + * Copyright (C) 2003 Tim Deegan (tjd21 at cl.cam.ac.uk) + * + * Parts based on GNU GRUB, Copyright (C) 2000 Free Software Foundation, Inc + * Parts copied from kexec-elf32-x86.c, written by Eric Biederman + * + * 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; either version 2 of the + * License, or (at your option) any later version. + * + * 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., 59 Temple Place - Suite 330, Boston, MA + * 02111-1307, USA. + * + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <errno.h> +#include <limits.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 "../../kexec.h" +#include "../../kexec-elf.h" +#include "kexec-x86.h" +#include <arch/options.h> + +/* From GNU GRUB */ +#include <x86/mb_header.h> +#include <x86/mb_info.h> + +/* Framebuffer */ +#include <sys/ioctl.h> +#include <linux/fb.h> + +extern struct arch_options_t arch_options; + +/* Static storage */ +static char headerbuf[MULTIBOOT_SEARCH]; +static struct multiboot_header *mbh = NULL; +static off_t mbh_offset = 0; + +#define MIN(_x,_y) (((_x)<=(_y))?(_x):(_y)) + + +int multiboot_x86_probe(const char *buf, off_t buf_len) +/* Is it a good idea to try booting this file? */ +{ + int i, len; + /* Now look for a multiboot header in the first 8KB */ + len = MULTIBOOT_SEARCH; + if (len > buf_len) { + len = buf_len; + } + memcpy(headerbuf, buf, len); + if (len < 12) { + /* Short file */ + return -1; + } + for (mbh_offset = 0; mbh_offset <= (len - 12); mbh_offset += 4) + { + /* Search for a multiboot header */ + mbh = (struct multiboot_header *)(headerbuf + mbh_offset); + if (mbh->magic != MULTIBOOT_MAGIC + || ((mbh->magic+mbh->flags+mbh->checksum) & 0xffffffff)) + { + /* Not a multiboot header */ + continue; + } + if (mbh->flags & MULTIBOOT_AOUT_KLUDGE) { + if (mbh->load_addr & 0xfff) { + fprintf(stderr, "multiboot load address not 4k aligned\n"); + return -1; + } + if (mbh->load_addr > mbh->header_addr) { + fprintf(stderr, "multiboot header address > load address\n"); + return -1; + } + if (mbh->load_end_addr < mbh->load_addr) { + fprintf(stderr, "multiboot load end address < load address\n"); + return -1; + } + if (mbh->bss_end_addr < mbh->load_end_addr) { + fprintf(stderr, "multiboot bss end address < load end address\n"); + return -1; + } + if (mbh->load_end_addr - mbh->header_addr > buf_len - mbh_offset) { + fprintf(stderr, "multiboot file truncated\n"); + return -1; + } + if (mbh->entry_addr < mbh->load_addr || mbh->entry_addr >= mbh->load_end_addr) { + fprintf(stderr, "multiboot entry out of range\n"); + return -1; + } + } else { + if ((i=elf_x86_probe(buf, buf_len)) < 0) + return i; + } + if (mbh->flags & MULTIBOOT_UNSUPPORTED) { + /* Requires options we don't support */ + fprintf(stderr, + "Found a multiboot header, but it " + "requires multiboot options that I\n" + "don't understand. Sorry.\n"); + return -1; + } + /* Bootable */ + return 0; + } + /* Not multiboot */ + return -1; +} + + +void multiboot_x86_usage(void) +/* Multiboot-specific options */ +{ + printf(" --command-line=STRING Set the kernel command line to STRING.\n"); + printf(" --reuse-cmdline Use kernel command line from running system.\n"); + printf(" --module=\"MOD arg1 arg2...\" Load module MOD with command-line \"arg1...\"\n"); + printf(" (can be used multiple times).\n"); +} + + +static int framebuffer_info(struct multiboot_info *mbi) +{ + struct fb_fix_screeninfo info; + struct fb_var_screeninfo mode; + int fd; + + /* check if purgatory will reset to standard ega text mode */ + if (arch_options.reset_vga || arch_options.console_vga) { + mbi->framebuffer_type = MB_FRAMEBUFFER_TYPE_EGA_TEXT; + mbi->framebuffer_addr = 0xb8000; + mbi->framebuffer_pitch = 80*2; + mbi->framebuffer_width = 80; + mbi->framebuffer_height = 25; + mbi->framebuffer_bpp = 16; + + mbi->flags |= MB_INFO_FRAMEBUFFER_INFO; + return 0; + } + + /* use current graphics framebuffer settings */ + fd = open("/dev/fb0", O_RDONLY); + if (fd < 0) { + fprintf(stderr, "can't open /dev/fb0: %s\n", strerror(errno)); + return -1; + } + if (ioctl(fd, FBIOGET_FSCREENINFO, &info) < 0){ + fprintf(stderr, "can't get screeninfo: %s\n", strerror(errno)); + close(fd); + return -1; + } + if (ioctl(fd, FBIOGET_VSCREENINFO, &mode) < 0){ + fprintf(stderr, "can't get modeinfo: %s\n", strerror(errno)); + close(fd); + return -1; + } + close(fd); + + if (info.smem_start == 0 || info.smem_len == 0) { + fprintf(stderr, "can't get linerar framebuffer address\n"); + return -1; + } + + if (info.type != FB_TYPE_PACKED_PIXELS) { + fprintf(stderr, "unsupported framebuffer type\n"); + return -1; + } + + if (info.visual != FB_VISUAL_TRUECOLOR) { + fprintf(stderr, "unsupported framebuffer visual\n"); + return -1; + } + + mbi->framebuffer_type = MB_FRAMEBUFFER_TYPE_RGB; + mbi->framebuffer_addr = info.smem_start; + mbi->framebuffer_pitch = info.line_length; + mbi->framebuffer_width = mode.xres; + mbi->framebuffer_height = mode.yres; + mbi->framebuffer_bpp = mode.bits_per_pixel; + mbi->framebuffer_red_field_position = mode.red.offset; + mbi->framebuffer_red_mask_size = mode.red.length; + mbi->framebuffer_green_field_position = mode.green.offset; + mbi->framebuffer_green_mask_size = mode.green.length; + mbi->framebuffer_blue_field_position = mode.blue.offset; + mbi->framebuffer_blue_mask_size = mode.blue.length; + + mbi->flags |= MB_INFO_FRAMEBUFFER_INFO; + return 0; +} + +int multiboot_x86_load(int argc, char **argv, const char *buf, off_t len, + struct kexec_info *info) +/* Marshal up a multiboot-style kernel */ +{ + struct multiboot_info *mbi; + void *mbi_buf; + struct mod_list *modp; + unsigned long freespace; + unsigned long long mem_lower = 0, mem_upper = 0; + struct mem_ehdr ehdr; + unsigned long mbi_base; + struct entry32_regs regs; + size_t mbi_bytes, mbi_offset; + char *command_line = NULL, *tmp_cmdline = NULL; + char *imagename, *cp, *append = NULL;; + struct memory_range *range; + int ranges; + struct AddrRangeDesc *mmap; + int command_line_len; + int i, result; + uint32_t u, entry; + int opt; + int modules, mod_command_line_space; + /* See options.h -- add any more there, too. */ + static const struct option options[] = { + KEXEC_ARCH_OPTIONS + { "command-line", 1, 0, OPT_CL }, + { "append", 1, 0, OPT_CL }, + { "reuse-cmdline", 0, 0, OPT_REUSE_CMDLINE }, + { "module", 1, 0, OPT_MOD }, + { 0, 0, 0, 0 }, + }; + static const char short_options[] = KEXEC_ARCH_OPT_STR ""; + + /* Probe for the MB header if it's not already found */ + if (mbh == NULL && multiboot_x86_probe(buf, len) != 1) { + fprintf(stderr, "Cannot find a loadable multiboot header.\n"); + return -1; + } + + /* Parse the command line */ + command_line_len = 0; + modules = 0; + mod_command_line_space = 0; + result = 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_CL: + append = optarg; + break; + case OPT_REUSE_CMDLINE: + command_line = get_command_line(); + break; + case OPT_MOD: + modules++; + mod_command_line_space += strlen(optarg) + 1; + break; + } + } + imagename = argv[optind]; + + /* Final command line = imagename + <OPT_REUSE_CMDLINE> + <OPT_CL> */ + tmp_cmdline = concat_cmdline(command_line, append); + if (command_line) { + free(command_line); + } + command_line = concat_cmdline(imagename, tmp_cmdline); + if (tmp_cmdline) { + free(tmp_cmdline); + } + command_line_len = strlen(command_line) + 1; + + if (mbh->flags & MULTIBOOT_AOUT_KLUDGE) { + add_segment(info, + buf + (mbh_offset - (mbh->header_addr - mbh->load_addr)), + mbh->load_end_addr - mbh->load_addr, + mbh->load_addr, + mbh->bss_end_addr - mbh->load_addr); + entry = mbh->entry_addr; + } else { + /* Load the ELF executable */ + elf_exec_build_load(info, &ehdr, buf, len, 0); + entry = ehdr.e_entry; + } + + /* Load the setup code */ + elf_rel_build_load(info, &info->rhdr, purgatory, purgatory_size, 0, + ULONG_MAX, 1, 0); + + /* The first segment will contain the multiboot headers: + * ============= + * multiboot information (mbi) + * ------------- + * kernel command line + * ------------- + * bootloader name + * ------------- + * module information entries + * ------------- + * module command lines + * ============== + */ + mbi_bytes = _ALIGN(sizeof(*mbi) + command_line_len + + strlen (BOOTLOADER " " BOOTLOADER_VERSION) + 1, 4); + mbi_buf = xmalloc(mbi_bytes); + mbi = mbi_buf; + memset(mbi, 0, sizeof(*mbi)); + sprintf(((char *)mbi) + sizeof(*mbi), "%s", command_line); + sprintf(((char *)mbi) + sizeof(*mbi) + command_line_len, "%s", + BOOTLOADER " " BOOTLOADER_VERSION); + mbi->flags = MB_INFO_CMDLINE | MB_INFO_BOOT_LOADER_NAME; + /* We'll relocate these to absolute addresses later. For now, + * all addresses within the first segment are relative to the + * start of the MBI. */ + mbi->cmdline = sizeof(*mbi); + mbi->boot_loader_name = sizeof(*mbi) + command_line_len; + + /* Memory map */ + range = info->memory_range; + ranges = info->memory_ranges; + mmap = xmalloc(ranges * sizeof(*mmap)); + for (i=0; i<ranges; i++) { + unsigned long long length; + length = range[i].end - range[i].start + 1; + /* Translate bzImage mmap to multiboot-speak */ + mmap[i].size = sizeof(mmap[i]) - 4; + mmap[i].base_addr_low = range[i].start & 0xffffffff; + mmap[i].base_addr_high = range[i].start >> 32; + mmap[i].length_low = length & 0xffffffff; + mmap[i].length_high = length >> 32; + switch (range[i].type) { + case RANGE_RAM: + mmap[i].Type = 1; /* RAM */ + /* + * Is this the "low" memory? Can't just test + * against zero, because Linux protects (and + * hides) the first few pages of physical + * memory. + */ + + if ((range[i].start <= 64*1024) + && (range[i].end > mem_lower)) { + range[i].start = 0; + mem_lower = range[i].end; + } + /* Is this the "high" memory? */ + if ((range[i].start <= 0x100000) + && (range[i].end > mem_upper + 0x100000)) + mem_upper = range[i].end - 0x100000; + break; + case RANGE_ACPI: + mmap[i].Type = 3; + break; + case RANGE_ACPI_NVS: + mmap[i].Type = 4; + break; + case RANGE_RESERVED: + default: + mmap[i].Type = 2; /* Not RAM (reserved) */ + } + } + + if (mbh->flags & MULTIBOOT_MEMORY_INFO) { + /* Provide a copy of the memory map to the kernel */ + + mbi->flags |= MB_INFO_MEMORY | MB_INFO_MEM_MAP; + + freespace = add_buffer(info, + mmap, ranges * sizeof(*mmap), ranges * sizeof(*mmap), + 4, 0, 0xFFFFFFFFUL, 1); + + mbi->mmap_addr = freespace; + mbi->mmap_length = ranges * sizeof(*mmap); + + /* For kernels that care naught for fancy memory maps + * and just want the size of low and high memory */ + mbi->mem_lower = MIN(mem_lower>>10, 0xffffffff); + mbi->mem_upper = MIN(mem_upper>>10, 0xffffffff); + + /* done */ + } + + /* Video */ + if (mbh->flags & MULTIBOOT_VIDEO_MODE) { + if (framebuffer_info(mbi) < 0) + fprintf(stderr, "not providing framebuffer information.\n"); + } + + /* Load modules */ + if (modules) { + char *mod_filename, *mod_command_line, *mod_clp, *buf; + off_t mod_size; + + /* We'll relocate this to an absolute address later */ + mbi->mods_addr = mbi_bytes; + mbi->mods_count = 0; + mbi->flags |= MB_INFO_MODS; + + /* Add room for the module descriptors to the MBI buffer */ + mbi_bytes += (sizeof(*modp) * modules) + + mod_command_line_space; + mbi_buf = xrealloc(mbi_buf, mbi_bytes); + + /* mbi might have moved */ + mbi = mbi_buf; + /* module descriptors go in the newly added space */ + modp = ((void *)mbi) + mbi->mods_addr; + /* module command lines go after the descriptors */ + mod_clp = ((void *)modp) + (sizeof(*modp) * modules); + + /* Go back and parse the module command lines */ + optind = opterr = 1; + while((opt = getopt_long(argc, argv, + short_options, options, 0)) != -1) { + if (opt != OPT_MOD) continue; + + /* Split module filename from command line */ + mod_command_line = mod_filename = optarg; + if ((cp = strchr(mod_filename, ' ')) != NULL) { + /* See as I discard the 'const' modifier */ + *cp = '\0'; + } + + /* Load the module */ + buf = slurp_decompress_file(mod_filename, &mod_size); + + if (cp != NULL) *cp = ' '; + + /* Pick the next aligned spot to load it in */ + freespace = add_buffer(info, + buf, mod_size, mod_size, + getpagesize(), 0, 0xffffffffUL, 1); + + /* Add the module command line */ + sprintf(mod_clp, "%s", mod_command_line); + + modp->mod_start = freespace; + modp->mod_end = freespace + mod_size; + modp->cmdline = (void *)mod_clp - (void *)mbi; + modp->pad = 0; + + /* Done */ + mbi->mods_count++; + mod_clp += strlen(mod_clp) + 1; + modp++; + } + } + + /* Find a place for the MBI to live */ + if (sort_segments(info) < 0) { + result = -1; + goto out; + } + mbi_base = add_buffer(info, + mbi_buf, mbi_bytes, mbi_bytes, 4, 0, 0xFFFFFFFFUL, 1); + + /* Relocate offsets in the MBI to absolute addresses */ + mbi_offset = mbi_base; + modp = ((void *)mbi) + mbi->mods_addr; + for (u = 0; u < mbi->mods_count; u++) { + modp[u].cmdline += mbi_offset; + } + mbi->mods_addr += mbi_offset; + mbi->cmdline += mbi_offset; + mbi->boot_loader_name += mbi_offset; + + /* Specify the initial CPU state and copy the setup code */ + elf_rel_get_symbol(&info->rhdr, "entry32_regs", ®s, sizeof(regs)); + regs.eax = 0x2BADB002; + regs.ebx = mbi_offset; + regs.eip = entry; + elf_rel_set_symbol(&info->rhdr, "entry32_regs", ®s, sizeof(regs)); + +out: + free(command_line); + return result; +} + +/* + * EOF (kexec-multiboot-x86.c) + */ |