Page MenuHomeFreeBSD
Files F81971304

D5992.diff
No OneTemporary
Actions

D5992.diff
View Options

Index: head/sys/boot/efi/loader/main.c
===================================================================
--- head/sys/boot/efi/loader/main.c
+++ head/sys/boot/efi/loader/main.c
@@ -795,6 +795,100 @@
COMMAND_SET(fdt, "fdt", "flattened device tree handling", command_fdt);
#endif
+/*
+ * Chain load another efi loader.
+ */
+static int
+command_chain(int argc, char *argv[])
+{
+ EFI_GUID LoadedImageGUID = LOADED_IMAGE_PROTOCOL;
+ EFI_HANDLE loaderhandle;
+ EFI_LOADED_IMAGE *loaded_image;
+ EFI_STATUS status;
+ struct stat st;
+ struct devdesc *dev;
+ char *name, *path;
+ void *buf;
+ int fd;
+
+ if (argc < 2) {
+ command_errmsg = "wrong number of arguments";
+ return (CMD_ERROR);
+ }
+
+ name = argv[1];
+
+ if ((fd = open(name, O_RDONLY)) < 0) {
+ command_errmsg = "no such file";
+ return (CMD_ERROR);
+ }
+
+ if (fstat(fd, &st) < -1) {
+ command_errmsg = "stat failed";
+ close(fd);
+ return (CMD_ERROR);
+ }
+
+ status = BS->AllocatePool(EfiLoaderCode, (UINTN)st.st_size, &buf);
+ if (status != EFI_SUCCESS) {
+ command_errmsg = "failed to allocate buffer";
+ close(fd);
+ return (CMD_ERROR);
+ }
+ if (read(fd, buf, st.st_size) != st.st_size) {
+ command_errmsg = "error while reading the file";
+ (void)BS->FreePool(buf);
+ close(fd);
+ return (CMD_ERROR);
+ }
+ close(fd);
+ status = BS->LoadImage(FALSE, IH, NULL, buf, st.st_size, &loaderhandle);
+ (void)BS->FreePool(buf);
+ if (status != EFI_SUCCESS) {
+ command_errmsg = "LoadImage failed";
+ return (CMD_ERROR);
+ }
+ status = BS->HandleProtocol(loaderhandle, &LoadedImageGUID,
+ (void **)&loaded_image);
+
+ if (argc > 2) {
+ int i, len = 0;
+ CHAR16 *argp;
+
+ for (i = 2; i < argc; i++)
+ len += strlen(argv[i]) + 1;
+
+ len *= sizeof (*argp);
+ loaded_image->LoadOptions = argp = malloc (len);
+ loaded_image->LoadOptionsSize = len;
+ for (i = 2; i < argc; i++) {
+ char *ptr = argv[i];
+ while (*ptr)
+ *(argp++) = *(ptr++);
+ *(argp++) = ' ';
+ }
+ *(--argv) = 0;
+ }
+
+ if (efi_getdev((void **)&dev, name, (const char **)&path) == 0)
+ loaded_image->DeviceHandle =
+ efi_find_handle(dev->d_dev, dev->d_unit);
+
+ dev_cleanup();
+ status = BS->StartImage(loaderhandle, NULL, NULL);
+ if (status != EFI_SUCCESS) {
+ command_errmsg = "StartImage failed";
+ free(loaded_image->LoadOptions);
+ loaded_image->LoadOptions = NULL;
+ status = BS->UnloadImage(loaded_image);
+ return (CMD_ERROR);
+ }
+
+ return (CMD_ERROR); /* not reached */
+}
+
+COMMAND_SET(chain, "chain", "chain load file", command_chain);
+
#ifdef EFI_ZFS_BOOT
static void
efi_zfs_probe(void)
Index: head/sys/boot/forth/menu.rc
===================================================================
--- head/sys/boot/forth/menu.rc
+++ head/sys/boot/forth/menu.rc
@@ -73,7 +73,22 @@
set mainmenu_command[7]="3 goto_menu"
set mainmenu_keycode[7]=101
set mainansi_caption[7]="Select Boot ^[1mE^[37mnvironment..."
+
+ s" chain_disk" getenv? [if]
+ set mainmenu_caption[8]="Chain[L]oad ${chain_disk}"
+ set mainmenu_command[8]="chain ${chain_disk}"
+ set mainmenu_keycode[8]=108
+ set mainansi_caption[8]="Chain^[1mL^[moad ${chain_disk}"
+ [then]
+[else]
+ s" chain_disk" getenv? [if]
+ set mainmenu_caption[7]="Chain[L]oad ${chain_disk}"
+ set mainmenu_command[7]="chain ${chain_disk}"
+ set mainmenu_keycode[7]=108
+ set mainansi_caption[7]="Chain^[1mL^[moad ${chain_disk}"
+ [then]
[then] [else] drop [then]
+
\
\ BOOT OPTIONS MENU
Index: head/sys/boot/i386/libi386/Makefile
===================================================================
--- head/sys/boot/i386/libi386/Makefile
+++ head/sys/boot/i386/libi386/Makefile
@@ -6,7 +6,7 @@
SRCS= biosacpi.c bioscd.c biosdisk.c biosmem.c biospnp.c \
biospci.c biossmap.c bootinfo.c bootinfo32.c bootinfo64.c \
comconsole.c devicename.c elf32_freebsd.c \
- elf64_freebsd.c multiboot.c multiboot_tramp.S \
+ elf64_freebsd.c multiboot.c multiboot_tramp.S relocater_tramp.S \
i386_copy.c i386_module.c nullconsole.c pxe.c pxetramp.s \
smbios.c time.c vidconsole.c amd64_tramp.S spinconsole.c
.PATH: ${.CURDIR}/../../zfs
Index: head/sys/boot/i386/libi386/libi386.h
===================================================================
--- head/sys/boot/i386/libi386/libi386.h
+++ head/sys/boot/i386/libi386/libi386.h
@@ -60,6 +60,35 @@
} d_kind;
};
+/*
+ * relocater trampoline support.
+ */
+struct relocate_data {
+ uint32_t src;
+ uint32_t dest;
+ uint32_t size;
+};
+
+extern void relocater(void);
+
+extern uint32_t relocater_data;
+extern uint32_t relocater_size;
+
+extern uint16_t relocator_ip;
+extern uint16_t relocator_cs;
+extern uint16_t relocator_ds;
+extern uint16_t relocator_es;
+extern uint16_t relocator_fs;
+extern uint16_t relocator_gs;
+extern uint16_t relocator_ss;
+extern uint16_t relocator_sp;
+extern uint32_t relocator_esi;
+extern uint32_t relocator_eax;
+extern uint32_t relocator_ebx;
+extern uint32_t relocator_edx;
+extern uint32_t relocator_ebp;
+extern uint16_t relocator_a20_enabled;
+
int i386_getdev(void **vdev, const char *devspec, const char **path);
char *i386_fmtdev(void *vdev);
int i386_setcurrdev(struct env_var *ev, int flags, const void *value);
Index: head/sys/boot/i386/libi386/relocater_tramp.S
===================================================================
--- head/sys/boot/i386/libi386/relocater_tramp.S
+++ head/sys/boot/i386/libi386/relocater_tramp.S
@@ -0,0 +1,358 @@
+/*-
+ * Copyright 2015 Toomas Soome <tsoome@me.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+
+/*
+ * relocate is needed to support loading code which has to be located
+ * below 1MB, as both BTX and loader are using low memory area.
+ *
+ * relocate and start loaded code. Since loaded code may need to be
+ * placed to already occupied memory area, this code is moved to safe
+ * memory area and then btx __exec will be called with physical pointer
+ * to this area. __exec will set pointer to %eax and use call *%eax,
+ * so on entry, we have new "base" address in %eax.
+ *
+ * Relocate will first set up and load new safe GDT to shut down BTX,
+ * then loaded code will be relocated to final memory location,
+ * then machine will be switched from 32bit protected mode to 16bit
+ * protected mode following by switch to real mode with A20 enabled or
+ * disabled. Finally the loaded code will be started and it will take
+ * over the whole system.
+ *
+ * For now, the known "safe" memory area for relocate is 0x600,
+ * the actual "free" memory is supposed to start from 0x500, leaving
+ * first 0x100 bytes in reserve. As relocate code+data is very small,
+ * it will leave enough space to set up boot blocks to 0:7c00 or load
+ * linux kernel below 1MB space.
+ */
+/*
+ * segment selectors
+ */
+ .set SEL_SCODE,0x8
+ .set SEL_SDATA,0x10
+ .set SEL_RCODE,0x18
+ .set SEL_RDATA,0x20
+
+ .p2align 4
+ .globl relocater
+relocater:
+ cli
+ /*
+ * set up GDT from new location
+ */
+ movl %eax, %esi /* our base address */
+ add $(relocater.1-relocater), %eax
+ jmp *%eax
+relocater.1:
+ /* set up jump */
+ lea (relocater.2-relocater)(%esi), %eax
+ movl %eax, (jump_vector-relocater) (%esi)
+
+ /* set up gdt */
+ lea (gdt-relocater) (%esi), %eax
+ movl %eax, (gdtaddr-relocater) (%esi)
+
+ /* load gdt */
+ lgdt (gdtdesc - relocater) (%esi)
+ lidt (idt-relocater) (%esi)
+
+ /* update cs */
+ ljmp *(jump_vector-relocater) (%esi)
+
+ .code32
+relocater.2:
+ xorl %eax, %eax
+ movb $SEL_SDATA, %al
+ movw %ax, %ss
+ movw %ax, %ds
+ movw %ax, %es
+ movw %ax, %fs
+ movw %ax, %gs
+ movl %cr0, %eax /* disable paging */
+ andl $~0x80000000,%eax
+ movl %eax, %cr0
+ xorl %ecx, %ecx /* flush TLB */
+ movl %ecx, %cr3
+ cld
+/*
+ * relocate data loop. load source, dest and size from
+ * relocater_data[i], 0 value will stop the loop.
+ * registers used for move: %esi, %edi, %ecx.
+ * %ebx to keep base
+ * %edx for relocater_data offset
+ */
+ movl %esi, %ebx /* base address */
+ xorl %edx, %edx
+loop.1:
+ movl (relocater_data-relocater)(%ebx, %edx, 4), %eax
+ testl %eax, %eax
+ jz loop.2
+ movl (relocater_data-relocater)(%ebx, %edx, 4), %esi
+ inc %edx
+ movl (relocater_data-relocater)(%ebx, %edx, 4), %edi
+ inc %edx
+ movl (relocater_data-relocater)(%ebx, %edx, 4), %ecx
+ inc %edx
+ rep
+ movsb
+ jmp loop.1
+loop.2:
+ movl %ebx, %esi /* restore esi */
+ /*
+ * data is relocated, switch to 16bit mode
+ */
+ lea (relocater.3-relocater)(%esi), %eax
+ movl %eax, (jump_vector-relocater) (%esi)
+ movl $SEL_RCODE, %eax
+ movl %eax, (jump_vector-relocater+4) (%esi)
+
+ ljmp *(jump_vector-relocater) (%esi)
+relocater.3:
+ .code16
+
+ movw $SEL_RDATA, %ax
+ movw %ax, %ds
+ movw %ax, %es
+ movw %ax, %fs
+ movw %ax, %gs
+ movw %ax, %ss
+ lidt (idt-relocater) (%esi)
+ lea (relocater.4-relocater)(%esi), %eax
+ movl %eax, (jump_vector-relocater) (%esi)
+ xorl %eax, %eax
+ movl %eax, (jump_vector-relocater+4) (%esi)
+ /* clear PE */
+ movl %cr0, %eax
+ dec %al
+ movl %eax, %cr0
+ ljmp *(jump_vector-relocater) (%esi)
+relocater.4:
+ xorw %ax, %ax
+ movw %ax, %ds
+ movw %ax, %es
+ movw %ax, %fs
+ movw %ax, %gs
+ movw %ax, %ss
+ /*
+ * set real mode irq offsets
+ */
+ movw $0x7008,%bx
+ in $0x21,%al # Save master
+ push %ax # IMR
+ in $0xa1,%al # Save slave
+ push %ax # IMR
+ movb $0x11,%al # ICW1 to
+ outb %al,$0x20 # master,
+ outb %al,$0xa0 # slave
+ movb %bl,%al # ICW2 to
+ outb %al,$0x21 # master
+ movb %bh,%al # ICW2 to
+ outb %al,$0xa1 # slave
+ movb $0x4,%al # ICW3 to
+ outb %al,$0x21 # master
+ movb $0x2,%al # ICW3 to
+ outb %al,$0xa1 # slave
+ movb $0x1,%al # ICW4 to
+ outb %al,$0x21 # master,
+ outb %al,$0xa1 # slave
+ pop %ax # Restore slave
+ outb %al,$0xa1 # IMR
+ pop %ax # Restore master
+ outb %al,$0x21 # IMR
+ # done
+ /*
+ * Should A20 be left enabled?
+ */
+ /* movw imm16, %ax */
+ .byte 0xb8
+ .globl relocator_a20_enabled
+relocator_a20_enabled:
+ .word 0
+ test %ax, %ax
+ jnz a20_done
+
+ movw $0xa00, %ax
+ movw %ax, %sp
+ movw %ax, %bp
+
+ /* Disable A20 */
+ movw $0x2400, %ax
+ int $0x15
+# jnc a20_done
+
+ call a20_check_state
+ testb %al, %al
+ jz a20_done
+
+ inb $0x92
+ andb $(~0x03), %al
+ outb $0x92
+ jmp a20_done
+
+a20_check_state:
+ movw $100, %cx
+1:
+ xorw %ax, %ax
+ movw %ax, %ds
+ decw %ax
+ movw %ax, %es
+ xorw %ax, %ax
+ movw $0x8000, %ax
+ movw %ax, %si
+ addw $0x10, %ax
+ movw %ax, %di
+ movb %ds:(%si), %dl
+ movb %es:(%di), %al
+ movb %al, %dh
+ decb %dh
+ movb %dh, %ds:(%si)
+ outb %al, $0x80
+ outb %al, $0x80
+ movb %es:(%di), %dh
+ subb %dh, %al
+ xorb $1, %al
+ movb %dl, %ds:(%si)
+ testb %al, %al
+ jz a20_done
+ loop 1b
+ ret
+a20_done:
+ /*
+ * set up registers
+ */
+ /* movw imm16, %ax. */
+ .byte 0xb8
+ .globl relocator_ds
+relocator_ds: .word 0
+ movw %ax, %ds
+
+ /* movw imm16, %ax. */
+ .byte 0xb8
+ .globl relocator_es
+relocator_es: .word 0
+ movw %ax, %es
+
+ /* movw imm16, %ax. */
+ .byte 0xb8
+ .globl relocator_fs
+relocator_fs: .word 0
+ movw %ax, %fs
+
+ /* movw imm16, %ax. */
+ .byte 0xb8
+ .globl relocator_gs
+relocator_gs: .word 0
+ movw %ax, %gs
+
+ /* movw imm16, %ax. */
+ .byte 0xb8
+ .globl relocator_ss
+relocator_ss: .word 0
+ movw %ax, %ss
+
+ /* movw imm16, %ax. */
+ .byte 0xb8
+ .globl relocator_sp
+relocator_sp: .word 0
+ movzwl %ax, %esp
+
+ /* movw imm32, %eax. */
+ .byte 0x66, 0xb8
+ .globl relocator_esi
+relocator_esi: .long 0
+ movl %eax, %esi
+
+ /* movw imm32, %edx. */
+ .byte 0x66, 0xba
+ .globl relocator_edx
+relocator_edx: .long 0
+
+ /* movw imm32, %ebx. */
+ .byte 0x66, 0xbb
+ .globl relocator_ebx
+relocator_ebx: .long 0
+
+ /* movw imm32, %eax. */
+ .byte 0x66, 0xb8
+ .globl relocator_eax
+relocator_eax: .long 0
+
+ /* movw imm32, %ebp. */
+ .byte 0x66, 0xbd
+ .globl relocator_ebp
+relocator_ebp: .long 0
+
+ sti
+ .byte 0xea /* ljmp */
+ .globl relocator_ip
+relocator_ip:
+ .word 0
+ .globl relocator_cs
+relocator_cs:
+ .word 0
+
+/* GDT to reset BTX */
+ .code32
+ .p2align 4
+jump_vector: .long 0
+ .long SEL_SCODE
+
+gdt: .word 0x0, 0x0 /* null entry */
+ .byte 0x0, 0x0, 0x0, 0x0
+ .word 0xffff, 0x0 /* SEL_SCODE */
+ .byte 0x0, 0x9a, 0xcf, 0x0
+ .word 0xffff, 0x0 /* SEL_SDATA */
+ .byte 0x0, 0x92, 0xcf, 0x0
+ .word 0xffff, 0x0 /* SEL_RCODE */
+ .byte 0x0, 0x9a, 0x0f, 0x0
+ .word 0xffff, 0x0 /* SEL_RDATA */
+ .byte 0x0, 0x92, 0x0f, 0x0
+gdt.1:
+
+gdtdesc: .word gdt.1 - gdt - 1 /* limit */
+gdtaddr: .long 0 /* base */
+
+idt: .word 0x3ff
+ .long 0
+
+ .globl relocater_data
+relocater_data:
+ .long 0 /* src */
+ .long 0 /* dest */
+ .long 0 /* size */
+ .long 0 /* src */
+ .long 0 /* dest */
+ .long 0 /* size */
+ .long 0 /* src */
+ .long 0 /* dest */
+ .long 0 /* size */
+ .long 0
+
+ .globl relocater_size
+relocater_size:
+ .long relocater_size-relocater
Index: head/sys/boot/i386/loader/Makefile
===================================================================
--- head/sys/boot/i386/loader/Makefile
+++ head/sys/boot/i386/loader/Makefile
@@ -14,7 +14,7 @@
LOADER_TFTP_SUPPORT?= yes
# architecture-specific loader code
-SRCS= main.c conf.c vers.c
+SRCS= main.c conf.c vers.c chain.c
# Put LOADER_FIREWIRE_SUPPORT=yes in /etc/make.conf for FireWire/dcons support
.if defined(LOADER_FIREWIRE_SUPPORT)
Index: head/sys/boot/i386/loader/chain.c
===================================================================
--- head/sys/boot/i386/loader/chain.c
+++ head/sys/boot/i386/loader/chain.c
@@ -0,0 +1,135 @@
+/*-
+ * Copyright 2015 Toomas Soome <tsoome@me.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Chain loader to load BIOS boot block either from MBR or PBR.
+ *
+ * Note the boot block location 0000:7c000 conflicts with loader, so we need to
+ * read in to temporary space and relocate on exec, when btx is stopped.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <stand.h>
+#include <sys/param.h>
+#include <sys/linker.h>
+#include <sys/diskmbr.h>
+
+#include "bootstrap.h"
+#include "libi386/libi386.h"
+#include "btxv86.h"
+
+/*
+ * The MBR/VBR is located in first sector of disk/partition.
+ * Read 512B to temporary location and set up relocation. Then
+ * exec relocator.
+ */
+#define SECTOR_SIZE (512)
+
+COMMAND_SET(chain, "chain", "chain load boot block from device", command_chain);
+
+static int
+command_chain(int argc, char *argv[])
+{
+ int fd, len, size = SECTOR_SIZE;
+ struct stat st;
+ vm_offset_t mem = 0x100000;
+ uint32_t *uintptr = &relocater_data;
+ struct i386_devdesc *rootdev;
+
+ if (argc == 1) {
+ command_errmsg = "no device or file name specified";
+ return (CMD_ERROR);
+ }
+ if (argc != 2) {
+ command_errmsg = "invalid trailing arguments";
+ return (CMD_ERROR);
+ }
+
+ fd = open(argv[1], O_RDONLY);
+ if (fd == -1) {
+ command_errmsg = "open failed";
+ return (CMD_ERROR);
+ }
+
+ len = strlen(argv[1]);
+ if (argv[1][len-1] != ':') {
+ if (fstat(fd, &st) == -1) {
+ command_errmsg = "stat failed";
+ close(fd);
+ return (CMD_ERROR);
+ }
+ size = st.st_size;
+ } else if (strncmp(argv[1], "disk", 4) != 0) {
+ command_errmsg = "can only use disk device";
+ close(fd);
+ return (CMD_ERROR);
+ }
+
+ i386_getdev((void **)(&rootdev), argv[1], NULL);
+ if (rootdev == NULL) {
+ command_errmsg = "can't determine root device";
+ return (CMD_ERROR);
+ }
+
+ if (archsw.arch_readin(fd, mem, SECTOR_SIZE) != SECTOR_SIZE) {
+ command_errmsg = "failed to read disk";
+ close(fd);
+ return (CMD_ERROR);
+ }
+ close(fd);
+
+ if (*((uint16_t *)PTOV(mem + DOSMAGICOFFSET)) != DOSMAGIC) {
+ command_errmsg = "wrong magic";
+ return (CMD_ERROR);
+ }
+
+ uintptr[0] = mem;
+ uintptr[1] = 0x7C00;
+ uintptr[2] = SECTOR_SIZE;
+
+ relocator_edx = bd_unit2bios(rootdev->d_unit);
+ relocator_esi = relocater_size;
+ relocator_ds = 0;
+ relocator_es = 0;
+ relocator_fs = 0;
+ relocator_gs = 0;
+ relocator_ss = 0;
+ relocator_cs = 0;
+ relocator_sp = 0x7C00;
+ relocator_ip = 0x7C00;
+ relocator_a20_enabled = 0;
+
+ i386_copyin(relocater, 0x600, relocater_size);
+
+ dev_cleanup();
+
+ __exec((void *)0x600);
+
+ panic("exec returned");
+ return (CMD_ERROR); /* not reached */
+}
Index: head/sys/boot/i386/loader/help.i386
===================================================================
--- head/sys/boot/i386/loader/help.i386
+++ head/sys/boot/i386/loader/help.i386
@@ -43,3 +43,12 @@
Displays the BIOS SMAP (system memory map) table.
################################################################################
+# Tchain DChain load disk block
+
+ chain disk:
+
+ chain will read stage1 (MBR or VBR) boot block from specified device
+ to address 0000:7C00 and attempts to run it. Use lsdev to get available
+ device names. Disk name must end with colon.
+
+################################################################################

File Metadata

Mime Type
text/plain
Expires
Mon, Dec 16, 1:40 AM (20 h, 26 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
9092189
Default Alt Text
D5992.diff (19 KB)

Event Timeline