rulimine/common/protos/multiboot2.c
Bryce Lanham fdcb9a9243 multiboot2: fix 32 bit elf section loading
Existing code was using 64 bit elf section header unconditionally. This
commit fixes that :)
2023-05-02 20:15:43 -05:00

846 lines
32 KiB
C

#if defined (__x86_64__) || defined (__i386__)
#include <stdint.h>
#include <stddef.h>
#include <stdnoreturn.h>
#include <protos/multiboot2.h>
#include <protos/multiboot.h>
#include <config.h>
#include <lib/libc.h>
#include <lib/elf.h>
#include <lib/misc.h>
#include <lib/config.h>
#include <lib/print.h>
#include <lib/uri.h>
#include <lib/fb.h>
#include <lib/term.h>
#include <lib/elsewhere.h>
#include <sys/pic.h>
#include <sys/cpu.h>
#include <sys/idt.h>
#include <fs/file.h>
#include <mm/vmm.h>
#include <lib/acpi.h>
#include <mm/pmm.h>
#include <lib/misc.h>
#include <drivers/vga_textmode.h>
#include <pxe/pxe.h>
#define LIMINE_BRAND "Limine " LIMINE_VERSION
/// Returns the size required to store the multiboot2 info.
static size_t get_multiboot2_info_size(
char *cmdline,
size_t modules_size,
uint32_t section_entry_size, uint32_t section_num,
uint32_t smbios_tag_size
) {
return ALIGN_UP(sizeof(struct multiboot2_start_tag), MULTIBOOT_TAG_ALIGN) + // start
ALIGN_UP(sizeof(struct multiboot_tag_string) + strlen(cmdline) + 1, MULTIBOOT_TAG_ALIGN) + // cmdline
ALIGN_UP(sizeof(struct multiboot_tag_string) + sizeof(LIMINE_BRAND), MULTIBOOT_TAG_ALIGN) + // bootloader brand
ALIGN_UP(sizeof(struct multiboot_tag_framebuffer), MULTIBOOT_TAG_ALIGN) + // framebuffer
ALIGN_UP(sizeof(struct multiboot_tag_new_acpi) + sizeof(struct rsdp), MULTIBOOT_TAG_ALIGN) + // new ACPI info
ALIGN_UP(sizeof(struct multiboot_tag_old_acpi) + 20, MULTIBOOT_TAG_ALIGN) + // old ACPI info
ALIGN_UP(sizeof(struct multiboot_tag_elf_sections) + section_entry_size * section_num, MULTIBOOT_TAG_ALIGN) + // ELF info
ALIGN_UP(modules_size, MULTIBOOT_TAG_ALIGN) + // modules
ALIGN_UP(sizeof(struct multiboot_tag_load_base_addr), MULTIBOOT_TAG_ALIGN) + // load base address
ALIGN_UP(smbios_tag_size, MULTIBOOT_TAG_ALIGN) + // SMBIOS
ALIGN_UP(sizeof(struct multiboot_tag_basic_meminfo), MULTIBOOT_TAG_ALIGN) + // basic memory info
ALIGN_UP(sizeof(struct multiboot_tag_mmap) + sizeof(struct multiboot_mmap_entry) * 256, MULTIBOOT_TAG_ALIGN) + // MMAP
#if defined (UEFI)
ALIGN_UP(sizeof(struct multiboot_tag_efi_mmap) + (efi_desc_size * 256), MULTIBOOT_TAG_ALIGN) + // EFI MMAP
#if defined (__i386__)
ALIGN_UP(sizeof(struct multiboot_tag_efi32), MULTIBOOT_TAG_ALIGN) + // EFI system table 32
ALIGN_UP(sizeof(struct multiboot_tag_efi32_ih), MULTIBOOT_TAG_ALIGN) + // EFI image handle 32
#elif defined (__x86_64__)
ALIGN_UP(sizeof(struct multiboot_tag_efi64), MULTIBOOT_TAG_ALIGN) + // EFI system table 64
ALIGN_UP(sizeof(struct multiboot_tag_efi64_ih), MULTIBOOT_TAG_ALIGN) + // EFI image handle 64
#endif
#endif
ALIGN_UP(sizeof(struct multiboot_tag_network) + DHCP_ACK_PACKET_LEN, MULTIBOOT_TAG_ALIGN) + // network info
ALIGN_UP(sizeof(struct multiboot_tag), MULTIBOOT_TAG_ALIGN); // end
}
#define append_tag(P, TAG) do { \
(P) += ALIGN_UP((TAG)->size, MULTIBOOT_TAG_ALIGN); \
} while (0)
noreturn void multiboot2_load(char *config, char* cmdline) {
struct file_handle *kernel_file;
char *kernel_path = config_get_value(config, 0, "KERNEL_PATH");
if (kernel_path == NULL)
panic(true, "multiboot2: KERNEL_PATH not specified");
print("multiboot2: Loading kernel `%#`...\n", kernel_path);
if ((kernel_file = uri_open(kernel_path)) == NULL)
panic(true, "multiboot2: Failed to open kernel with path `%#`. Is the path correct?", kernel_path);
uint8_t *kernel = freadall(kernel_file, MEMMAP_KERNEL_AND_MODULES);
size_t kernel_file_size = kernel_file->size;
fclose(kernel_file);
struct multiboot_header *header;
for (size_t header_offset = 0; header_offset < MULTIBOOT_SEARCH; header_offset += MULTIBOOT_HEADER_ALIGN) {
header = (void *)(kernel + header_offset);
if (header->magic == MULTIBOOT2_HEADER_MAGIC) {
break;
}
}
if (header->magic != MULTIBOOT2_HEADER_MAGIC) {
panic(true, "multiboot2: Invalid magic");
}
if (header->magic + header->architecture + header->checksum + header->header_length) {
panic(true, "multiboot2: Header checksum is invalid");
}
struct multiboot_header_tag_address *addresstag = NULL;
struct multiboot_header_tag_framebuffer *fbtag = NULL;
bool has_reloc_header = false;
bool is_new_acpi_required = false;
bool is_old_acpi_required = false;
bool is_elf_info_requested = false;
#if defined (UEFI)
bool is_framebuffer_required = false;
#endif
uint64_t entry_point = 0xffffffff;
// Iterate through the entries...
for (struct multiboot_header_tag *tag = (struct multiboot_header_tag*)(header + 1); // header + 1 to skip the header struct.
tag < (struct multiboot_header_tag *)((uintptr_t)header + header->header_length) && tag->type != MULTIBOOT_HEADER_TAG_END;
tag = (struct multiboot_header_tag *)((uintptr_t)tag + ALIGN_UP(tag->size, MULTIBOOT_TAG_ALIGN))) {
bool is_required = !(tag->flags & MULTIBOOT_HEADER_TAG_OPTIONAL);
switch (tag->type) {
case MULTIBOOT_HEADER_TAG_INFORMATION_REQUEST: {
// Iterate the requests and check if they are supported by or not.
struct multiboot_header_tag_information_request *request = (void *)tag;
uint32_t size = (request->size - sizeof(struct multiboot_header_tag_information_request)) / sizeof(uint32_t);
for (uint32_t i = 0; i < size; i++) {
uint32_t r = request->requests[i];
switch (r) {
// We already support the following requests:
case MULTIBOOT_TAG_TYPE_CMDLINE:
case MULTIBOOT_TAG_TYPE_BOOT_LOADER_NAME:
case MULTIBOOT_TAG_TYPE_MODULE:
case MULTIBOOT_TAG_TYPE_MMAP:
case MULTIBOOT_TAG_TYPE_SMBIOS:
case MULTIBOOT_TAG_TYPE_BASIC_MEMINFO:
#if defined (UEFI)
case MULTIBOOT_TAG_TYPE_EFI_MMAP:
#if defined (__i386__)
case MULTIBOOT_TAG_TYPE_EFI32:
case MULTIBOOT_TAG_TYPE_EFI32_IH:
#elif defined (__x86_64__)
case MULTIBOOT_TAG_TYPE_EFI64:
case MULTIBOOT_TAG_TYPE_EFI64_IH:
#endif
#endif
break;
case MULTIBOOT_TAG_TYPE_FRAMEBUFFER:
#if defined (UEFI)
is_framebuffer_required = is_required;
#endif
break;
case MULTIBOOT_TAG_TYPE_ACPI_NEW:
is_new_acpi_required = is_required;
break;
case MULTIBOOT_TAG_TYPE_ACPI_OLD:
is_old_acpi_required = is_required;
break;
case MULTIBOOT_TAG_TYPE_ELF_SECTIONS:
is_elf_info_requested = is_required;
break;
default:
if (is_required)
panic(true, "multiboot2: Requested tag `%d` which is not supported", r);
break;
}
}
break;
}
case MULTIBOOT_HEADER_TAG_FRAMEBUFFER: {
fbtag = (void *)tag;
break;
}
case MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS: {
struct multiboot_header_tag_entry_address *entrytag = (void *)tag;
entry_point = entrytag->entry_addr;
break;
}
case MULTIBOOT_HEADER_TAG_ADDRESS: {
addresstag = (void *)tag;
break;
}
// We always align the modules ;^)
case MULTIBOOT_HEADER_TAG_MODULE_ALIGN:
case MULTIBOOT_HEADER_TAG_EFI_BS:
break;
case MULTIBOOT_HEADER_TAG_RELOCATABLE:
has_reloc_header = true;
break;
default:
if (is_required)
panic(true, "multiboot2: Unknown header tag type: %u\n", tag->type);
}
}
bool section_hdr_info_valid = false;
struct elf_section_hdr_info section_hdr_info = {0};
struct elsewhere_range *ranges;
uint64_t ranges_count;
if (addresstag != NULL) {
size_t header_offset = (size_t)header - (size_t)kernel;
uintptr_t load_src, load_addr;
if (addresstag->load_addr != (uint32_t)-1) {
if (addresstag->load_addr > addresstag->header_addr) {
panic(true, "multiboot2: Illegal load address");
}
load_src = header_offset - (addresstag->header_addr - addresstag->load_addr);
load_addr = addresstag->load_addr;
} else {
load_src = 0;
load_addr = addresstag->header_addr - header_offset;
}
size_t load_size;
if (addresstag->load_end_addr != 0) {
load_size = addresstag->load_end_addr - load_addr;
} else {
load_size = kernel_file_size - load_src;
}
size_t bss_size = 0;
if (addresstag->bss_end_addr != 0) {
uintptr_t bss_addr = load_addr + load_size;
if (addresstag->bss_end_addr < bss_addr) {
panic(true, "multiboot2: Illegal bss end address");
}
bss_size = addresstag->bss_end_addr - bss_addr;
}
size_t full_size = load_size + bss_size;
void *elsewhere = ext_mem_alloc(full_size);
memcpy(elsewhere, kernel + load_src, load_size);
if (entry_point == 0xffffffff) {
panic(true, "multiboot2: Using address tag but entry address tag missing");
}
ranges_count = 1;
ranges = ext_mem_alloc(sizeof(struct elsewhere_range));
ranges->elsewhere = (uintptr_t)elsewhere;
ranges->target = load_addr;
ranges->length = full_size;
} else {
uint64_t e;
int bits = elf_bits(kernel);
switch (bits) {
case 32:
if (!elf32_load_elsewhere(kernel, &e, &ranges, &ranges_count))
panic(true, "multiboot2: ELF32 load failure");
section_hdr_info = elf32_section_hdr_info(kernel);
section_hdr_info_valid = true;
break;
case 64: {
if (!elf64_load_elsewhere(kernel, &e, &ranges, &ranges_count))
panic(true, "multiboot2: ELF64 load failure");
section_hdr_info = elf64_section_hdr_info(kernel);
section_hdr_info_valid = true;
break;
}
default:
panic(true, "multiboot2: Invalid ELF file bitness");
}
if (entry_point == 0xffffffff) {
entry_point = e;
}
}
// Get the load base address (AKA the lowest target in the ranges)
uint64_t load_base_addr = (uint64_t)-1;
for (size_t i = 0; i < ranges_count; i++) {
if (load_base_addr > ranges[i].target) {
load_base_addr = ranges[i].target;
}
}
size_t modules_size = 0;
size_t n_modules;
for (n_modules = 0;; n_modules++) {
struct conf_tuple conf_tuple = config_get_tuple(config, n_modules, "MODULE_PATH", "MODULE_STRING");
if (!conf_tuple.value1) break;
char *module_cmdline = conf_tuple.value2;
if (!module_cmdline) module_cmdline = "";
modules_size += sizeof(struct multiboot_tag_module) + strlen(module_cmdline) + 1;
}
struct smbios_entry_point_32* smbios_entry_32 = NULL;
struct smbios_entry_point_64* smbios_entry_64 = NULL;
acpi_get_smbios((void **)&smbios_entry_32, (void **)&smbios_entry_64);
uint32_t smbios_tag_size = 0;
if (smbios_entry_32 != NULL)
smbios_tag_size += sizeof(struct multiboot_tag_smbios) + smbios_entry_32->length;
if (smbios_entry_64 != NULL)
smbios_tag_size += sizeof(struct multiboot_tag_smbios) + smbios_entry_64->length;
size_t mb2_info_size = get_multiboot2_info_size(
cmdline,
modules_size,
section_hdr_info_valid ? section_hdr_info.section_entry_size : 0,
section_hdr_info_valid ? section_hdr_info.num : 0,
smbios_tag_size
);
size_t info_idx = 0;
// Realloc elsewhere ranges to include mb2 info, modules, and elf sections
struct elsewhere_range *new_ranges = ext_mem_alloc(sizeof(struct elsewhere_range) *
(ranges_count
+ 1 /* mb2 info range */
+ n_modules
+ (section_hdr_info_valid ? section_hdr_info.num : 0)));
memcpy(new_ranges, ranges, sizeof(struct elsewhere_range) * ranges_count);
pmm_free(ranges, sizeof(struct elsewhere_range) * ranges_count);
ranges = new_ranges;
// GRUB allocates boot info at 0x10000, *except* if the kernel happens
// to overlap this region, then it gets moved to right after the
// kernel, or whichever PHDR happens to sit at 0x10000.
// Allocate it wherever, then move it to where GRUB puts it
// afterwards.
// Elsewhere append mb2 info *after* kernel but *before* modules.
uint8_t *mb2_info = ext_mem_alloc(mb2_info_size);
uint64_t mb2_info_final_loc = 0x10000;
if (!elsewhere_append(true /* flexible target */,
ranges, &ranges_count,
mb2_info, &mb2_info_final_loc, mb2_info_size)) {
panic(true, "multiboot2: Cannot allocate mb2 info");
}
struct multiboot2_start_tag *mbi_start = (struct multiboot2_start_tag *)mb2_info;
info_idx += sizeof(struct multiboot2_start_tag);
//////////////////////////////////////////////
// Create ELF info tag
//////////////////////////////////////////////
if (section_hdr_info_valid == false) {
if (is_elf_info_requested) {
panic(true, "multiboot2: Cannot return ELF file information");
}
} else {
uint32_t size = sizeof(struct multiboot_tag_elf_sections) + section_hdr_info.section_entry_size * section_hdr_info.num;
struct multiboot_tag_elf_sections *tag = (struct multiboot_tag_elf_sections*)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_ELF_SECTIONS;
tag->size = size;
tag->num = section_hdr_info.num;
tag->entsize = section_hdr_info.section_entry_size;
tag->shndx = section_hdr_info.str_section_idx;
memcpy(tag->sections, kernel + section_hdr_info.section_offset, section_hdr_info.section_entry_size * section_hdr_info.num);
int bits = elf_bits(kernel);
for (size_t i = 0; i < section_hdr_info.num; i++) {
if (bits == 64) {
struct elf64_shdr *shdr = (void *)tag->sections + i * section_hdr_info.section_entry_size;
if (shdr->sh_addr != 0 || shdr->sh_size == 0) {
continue;
}
uint64_t section = (uint64_t)-1; /* no target preference, use top */
if (!elsewhere_append(true /* flexible target */,
ranges, &ranges_count,
kernel + shdr->sh_offset, &section, shdr->sh_size)) {
panic(true, "multiboot2: Cannot allocate elf sections");
}
shdr->sh_addr = section;
} else {
struct elf32_shdr *shdr = (void *)tag->sections + i * section_hdr_info.section_entry_size;
if (shdr->sh_addr != 0 || shdr->sh_size == 0) {
continue;
}
uint64_t section = (uint64_t)-1; /* no target preference, use top */
if (!elsewhere_append(true /* flexible target */,
ranges, &ranges_count,
kernel + shdr->sh_offset, &section, shdr->sh_size)) {
panic(true, "multiboot2: Cannot allocate elf sections");
}
shdr->sh_addr = section;
}
}
append_tag(info_idx, tag);
}
//////////////////////////////////////////////
// Create load base address tag
//////////////////////////////////////////////
if (has_reloc_header) {
uint32_t size = sizeof(struct multiboot_tag_load_base_addr);
struct multiboot_tag_load_base_addr *tag = (void *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_LOAD_BASE_ADDR;
tag->size = size;
tag->load_base_addr = load_base_addr;
append_tag(info_idx, tag);
}
//////////////////////////////////////////////
// Create modules tag
//////////////////////////////////////////////
for (size_t i = 0; i < n_modules; i++) {
struct conf_tuple conf_tuple = config_get_tuple(config, i, "MODULE_PATH", "MODULE_STRING");
char *module_path = conf_tuple.value1;
if (!module_path) panic(true, "multiboot2: Module disappeared unexpectedly");
print("multiboot2: Loading module `%#`...\n", module_path);
struct file_handle *f;
if ((f = uri_open(module_path)) == NULL)
panic(true, "multiboot2: Failed to open module with path `%#`. Is the path correct?", module_path);
// Module commandline can be null, so we guard against that and make the
// string "".
char *module_cmdline = conf_tuple.value2;
if (!module_cmdline) module_cmdline = "";
void *module_addr = freadall(f, MEMMAP_BOOTLOADER_RECLAIMABLE);
uint64_t module_target = (uint64_t)-1;
if (!elsewhere_append(true /* flexible target */,
ranges, &ranges_count,
module_addr, &module_target, f->size)) {
panic(true, "multiboot2: Cannot allocate module");
}
struct multiboot_tag_module *module_tag = (struct multiboot_tag_module *)(mb2_info + info_idx);
module_tag->type = MULTIBOOT_TAG_TYPE_MODULE;
module_tag->size = sizeof(struct multiboot_tag_module) + strlen(module_cmdline) + 1;
module_tag->mod_start = module_target;
module_tag->mod_end = module_tag->mod_start + f->size;
strcpy(module_tag->cmdline, module_cmdline); // Copy over the command line
fclose(f);
if (verbose) {
print("multiboot2: Requested module %u:\n", i);
print(" Path: %s\n", module_path);
print(" String: \"%s\"\n", module_cmdline ?: "");
print(" Begin: %x\n", module_tag->mod_start);
print(" End: %x\n", module_tag->mod_end);
}
append_tag(info_idx, module_tag);
}
//////////////////////////////////////////////
// Create command line tag
//////////////////////////////////////////////
{
uint32_t size = sizeof(struct multiboot_tag_string) + strlen(cmdline) + 1;
struct multiboot_tag_string *tag = (struct multiboot_tag_string *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_CMDLINE;
tag->size = size;
strcpy(tag->string, cmdline);
append_tag(info_idx, tag);
}
//////////////////////////////////////////////
// Create bootloader name tag
//////////////////////////////////////////////
{
uint32_t size = sizeof(struct multiboot_tag_string) + sizeof(LIMINE_BRAND);
struct multiboot_tag_string *tag = (struct multiboot_tag_string *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_BOOT_LOADER_NAME;
tag->size = size;
strcpy(tag->string, LIMINE_BRAND);
append_tag(info_idx, tag);
}
//////////////////////////////////////////////
// Create EFI image handle tag
//////////////////////////////////////////////
#if defined (UEFI)
{
#if defined (__i386__)
struct multiboot_tag_efi64_ih *tag = (struct multiboot_tag_efi64_ih *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_EFI64_IH;
tag->size = sizeof(struct multiboot_tag_efi64_ih);
#elif defined (__x86_64__)
struct multiboot_tag_efi32_ih *tag = (struct multiboot_tag_efi32_ih *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_EFI32_IH;
tag->size = sizeof(struct multiboot_tag_efi32_ih);
#endif
tag->pointer = (uintptr_t)efi_image_handle;
append_tag(info_idx, tag);
}
#endif
//////////////////////////////////////////////
// Create framebuffer tag
//////////////////////////////////////////////
{
struct multiboot_tag_framebuffer *tag = (struct multiboot_tag_framebuffer *)(mb2_info + info_idx);
tag->common.type = MULTIBOOT_TAG_TYPE_FRAMEBUFFER;
tag->common.size = sizeof(struct multiboot_tag_framebuffer);
term_notready();
size_t req_width = 0;
size_t req_height = 0;
size_t req_bpp = 0;
#if defined (BIOS)
{
char *textmode_str = config_get_value(config, 0, "TEXTMODE");
bool textmode = textmode_str != NULL && strcmp(textmode_str, "yes") == 0;
if (textmode) {
goto textmode;
}
}
#endif
if (fbtag) {
req_width = fbtag->width;
req_height = fbtag->height;
req_bpp = fbtag->depth;
#if defined (UEFI)
modeset:;
#endif
char *resolution = config_get_value(config, 0, "RESOLUTION");
if (resolution != NULL)
parse_resolution(&req_width, &req_height, &req_bpp, resolution);
struct fb_info *fbs;
size_t fbs_count;
fb_init(&fbs, &fbs_count, req_width, req_height, req_bpp);
if (fbs_count == 0) {
#if defined (BIOS)
textmode:
vga_textmode_init(false);
tag->common.framebuffer_addr = 0xb8000;
tag->common.framebuffer_pitch = 2 * 80;
tag->common.framebuffer_width = 80;
tag->common.framebuffer_height = 25;
tag->common.framebuffer_bpp = 16;
tag->common.framebuffer_type = MULTIBOOT_FRAMEBUFFER_TYPE_EGA_TEXT;
#elif defined (UEFI)
if (is_framebuffer_required) {
panic(true, "multiboot2: Failed to set video mode");
} else {
goto skip_modeset;
}
#endif
} else {
tag->common.framebuffer_addr = fbs[0].framebuffer_addr;
tag->common.framebuffer_pitch = fbs[0].framebuffer_pitch;
tag->common.framebuffer_width = fbs[0].framebuffer_width;
tag->common.framebuffer_height = fbs[0].framebuffer_height;
tag->common.framebuffer_bpp = fbs[0].framebuffer_bpp;
tag->common.framebuffer_type = MULTIBOOT_FRAMEBUFFER_TYPE_RGB; // We only support RGB for VBE
tag->framebuffer_red_field_position = fbs[0].red_mask_shift;
tag->framebuffer_red_mask_size = fbs[0].red_mask_size;
tag->framebuffer_green_field_position = fbs[0].green_mask_shift;
tag->framebuffer_green_mask_size = fbs[0].green_mask_size;
tag->framebuffer_blue_field_position = fbs[0].blue_mask_shift;
tag->framebuffer_blue_mask_size = fbs[0].blue_mask_size;
}
} else {
#if defined (UEFI)
print("multiboot2: Warning: Cannot use text mode with UEFI\n");
goto modeset;
#elif defined (BIOS)
goto textmode;
#endif
}
append_tag(info_idx, &tag->common);
#if defined (UEFI)
skip_modeset:;
#endif
}
//////////////////////////////////////////////
// Create new ACPI info tag
//////////////////////////////////////////////
{
void *new_rsdp = acpi_get_rsdp_v2();
if (new_rsdp != NULL) {
uint32_t size = sizeof(struct multiboot_tag_new_acpi) + sizeof(struct rsdp); // XSDP is 36 bytes wide
struct multiboot_tag_new_acpi *tag = (struct multiboot_tag_new_acpi *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_ACPI_NEW;
tag->size = size;
memcpy(tag->rsdp, new_rsdp, sizeof(struct rsdp));
append_tag(info_idx, tag);
} else if (is_new_acpi_required) {
panic(true, "multiboot2: XSDP requested but not found");
}
}
//////////////////////////////////////////////
// Create old ACPI info tag
//////////////////////////////////////////////
{
void *old_rsdp = acpi_get_rsdp_v1();
if (old_rsdp != NULL) {
uint32_t size = sizeof(struct multiboot_tag_old_acpi) + 20; // RSDP is 20 bytes wide
struct multiboot_tag_old_acpi *tag = (struct multiboot_tag_old_acpi *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_ACPI_OLD;
tag->size = size;
memcpy(tag->rsdp, old_rsdp, 20);
append_tag(info_idx, tag);
} else if (is_old_acpi_required) {
panic(true, "multiboot2: RSDP requested but not found");
}
}
//////////////////////////////////////////////
// Create SMBIOS tag
//////////////////////////////////////////////
{
// NOTE: The multiboot2 specification does not say anything about if both
// smbios 32 and 64 bit entry points are present, then we pass both of them + smbios
// support for grub2 is unimplemented. So, we are going to assume they expect us to
// pass both of them if avaliable. Oh well...
if (smbios_entry_32 != NULL) {
struct multiboot_tag_smbios *tag = (struct multiboot_tag_smbios *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_SMBIOS;
tag->size = sizeof(struct multiboot_tag_smbios);
tag->major = smbios_entry_32->major_version;
tag->minor = smbios_entry_32->minor_version;
memset(tag->reserved, 0, 6);
memcpy(tag->tables, smbios_entry_32, smbios_entry_32->length);
append_tag(info_idx, tag);
}
if (smbios_entry_64 != NULL) {
struct multiboot_tag_smbios *tag = (struct multiboot_tag_smbios *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_SMBIOS;
tag->size = sizeof(struct multiboot_tag_smbios);
tag->major = smbios_entry_64->major_version;
tag->minor = smbios_entry_64->minor_version;
memset(tag->reserved, 0, 6);
memcpy(tag->tables, smbios_entry_64, smbios_entry_64->length);
append_tag(info_idx, tag);
}
}
//////////////////////////////////////////////
// Create EFI system table info tag
//////////////////////////////////////////////
#if defined (UEFI)
{
#if defined (__i386__)
uint32_t size = sizeof(struct multiboot_tag_efi32);
struct multiboot_tag_efi32 *tag = (void *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_EFI32;
#elif defined (__x86_64__)
uint32_t size = sizeof(struct multiboot_tag_efi64);
struct multiboot_tag_efi64 *tag = (void *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_EFI64;
#endif
tag->size = size;
tag->pointer = (uintptr_t)gST;
append_tag(info_idx, tag);
}
#endif
// Load relocation stub where it won't get overwritten (hopefully)
size_t reloc_stub_size = (size_t)multiboot_reloc_stub_end - (size_t)multiboot_reloc_stub;
void *reloc_stub = ext_mem_alloc(reloc_stub_size);
memcpy(reloc_stub, multiboot_reloc_stub, reloc_stub_size);
#if defined (UEFI)
efi_exit_boot_services();
#endif
size_t mb_mmap_count;
struct memmap_entry *raw_memmap = get_raw_memmap(&mb_mmap_count);
//////////////////////////////////////////////
// Create memory map tag
//////////////////////////////////////////////
{
if (mb_mmap_count > 256) {
panic(false, "multiboot2: too many memory map entries");
}
// Create the normal memory map tag.
uint32_t mmap_size = sizeof(struct multiboot_tag_mmap) + sizeof(struct multiboot_mmap_entry) * mb_mmap_count;
struct multiboot_tag_mmap *mmap_tag = (struct multiboot_tag_mmap *)(mb2_info + info_idx);
mmap_tag->type = MULTIBOOT_TAG_TYPE_MMAP;
mmap_tag->entry_size = sizeof(struct multiboot_mmap_entry);
mmap_tag->entry_version = 0;
mmap_tag->size = mmap_size;
for (size_t i = 0; i < mb_mmap_count; i++) {
struct multiboot_mmap_entry *entry = &mmap_tag->entries[i];
entry->addr = raw_memmap[i].base;
entry->len = raw_memmap[i].length;
entry->type = raw_memmap[i].type;
entry->zero = 0;
}
append_tag(info_idx, mmap_tag);
}
//////////////////////////////////////////////
// Create basic memory info tag
//////////////////////////////////////////////
{
struct meminfo meminfo = mmap_get_info(mb_mmap_count, raw_memmap);
struct multiboot_tag_basic_meminfo *tag = (struct multiboot_tag_basic_meminfo *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_BASIC_MEMINFO;
tag->size = sizeof(struct multiboot_tag_basic_meminfo);
// Convert the uppermem and lowermem fields from bytes to
// KiB.
tag->mem_upper = (uint32_t)(meminfo.uppermem / 1024);
tag->mem_lower = (uint32_t)(meminfo.lowermem / 1024);
append_tag(info_idx, tag);
}
//////////////////////////////////////////////
// Create EFI memory map tag
//////////////////////////////////////////////
#if defined (UEFI)
{
if ((efi_mmap_size / efi_desc_size) > 256) {
panic(false, "multiboot2: too many EFI memory map entries");
}
// Create the EFI memory map tag.
uint32_t size = sizeof(struct multiboot_tag_efi_mmap) + efi_mmap_size;
struct multiboot_tag_efi_mmap *mmap_tag = (struct multiboot_tag_efi_mmap *)(mb2_info + info_idx);
mmap_tag->type = MULTIBOOT_TAG_TYPE_EFI_MMAP;
mmap_tag->descr_vers = efi_desc_ver;
mmap_tag->descr_size = efi_desc_size;
mmap_tag->size = size;
// Copy over the EFI memory map.
memcpy(mmap_tag->efi_mmap, efi_mmap, efi_mmap_size);
append_tag(info_idx, mmap_tag);
}
#endif
//////////////////////////////////////////////
// Create network info tag
//////////////////////////////////////////////
{
if (cached_dhcp_ack_valid) {
struct multiboot_tag_network *tag = (struct multiboot_tag_network *)(mb2_info + info_idx);
tag->type = MULTIBOOT_TAG_TYPE_NETWORK;
tag->size = sizeof(struct multiboot_tag_network) + DHCP_ACK_PACKET_LEN;
// Copy over the DHCP packet.
memcpy(tag->dhcpack, cached_dhcp_packet, DHCP_ACK_PACKET_LEN);
append_tag(info_idx, tag);
}
}
//////////////////////////////////////////////
// Create end tag
//////////////////////////////////////////////
{
struct multiboot_tag *end_tag = (struct multiboot_tag *)(mb2_info + info_idx);
end_tag->type = MULTIBOOT_TAG_TYPE_END;
end_tag->size = sizeof(struct multiboot_tag);
append_tag(info_idx, end_tag);
}
mbi_start->size = info_idx;
mbi_start->reserved = 0x00;
irq_flush_type = IRQ_PIC_ONLY_FLUSH;
common_spinup(multiboot_spinup_32, 6,
(uint32_t)(uintptr_t)reloc_stub, (uint32_t)0x36d76289,
(uint32_t)mb2_info_final_loc, (uint32_t)entry_point,
(uint32_t)(uintptr_t)ranges, (uint32_t)ranges_count);
}
#endif