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* [PATCH 1/2] Relocator framework
@ 2009-08-03 12:06 Vladimir 'phcoder' Serbinenko
  2009-08-03 12:39 ` Vladimir 'phcoder' Serbinenko
  2009-08-04 20:52 ` Robert Millan
  0 siblings, 2 replies; 9+ messages in thread
From: Vladimir 'phcoder' Serbinenko @ 2009-08-03 12:06 UTC (permalink / raw)
  To: The development of GRUB 2

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Hello. As discussed on IRC it would be preferable if all loaders use
flexible technics for loading kernels using relocators as currently
multiboot and xnu does. Here is a relocator framework based on
multiboot and xnu relocator. As an advantage it switches from x86-64
to i386 if necessary. With it and some more patches I was able to load
mbtest on qemu64 with tianocore

-- 
Regards
Vladimir 'phcoder' Serbinenko

Personal git repository: http://repo.or.cz/w/grub2/phcoder.git

[-- Attachment #2: relocator.diff --]
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diff --git a/conf/i386.rmk b/conf/i386.rmk
index 93f84ce..33d49b5 100644
--- a/conf/i386.rmk
+++ b/conf/i386.rmk
@@ -14,3 +14,9 @@ pkglib_MODULES += vga_text.mod
 vga_text_mod_SOURCES = term/i386/pc/vga_text.c term/i386/vga_common.c
 vga_text_mod_CFLAGS = $(COMMON_CFLAGS)
 vga_text_mod_LDFLAGS = $(COMMON_LDFLAGS)
+
+pkglib_MODULES += relocator.mod
+relocator_mod_SOURCES = lib/i386/relocator.c lib/i386/relocator_asm.S lib/i386/relocator_backward.S
+relocator_mod_CFLAGS = $(COMMON_CFLAGS)
+relocator_mod_ASFLAGS = $(COMMON_ASFLAGS)
+relocator_mod_LDFLAGS = $(COMMON_LDFLAGS)
diff --git a/include/grub/i386/relocator.h b/include/grub/i386/relocator.h
new file mode 100644
index 0000000..cbc75ed
--- /dev/null
+++ b/include/grub/i386/relocator.h
@@ -0,0 +1,40 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2009  Free Software Foundation, Inc.
+ *
+ *  GRUB 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 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef GRUB_RELOCATOR_CPU_HEADER
+#define GRUB_RELOCATOR_CPU_HEADER	1
+
+struct grub_relocator32_state
+{
+  grub_uint32_t esp;
+  grub_uint32_t eax;
+  grub_uint32_t ebx;
+  grub_uint32_t ecx;
+  grub_uint32_t edx;
+  grub_uint32_t eip;
+};
+
+void *
+grub_relocator32_alloc (grub_size_t size);
+grub_err_t
+grub_relocator32_boot (void *relocator, grub_uint32_t dest,
+		       struct grub_relocator32_state state);
+void
+grub_relocator32_free (void *relocator);
+
+#endif /* ! GRUB_RELOCATOR_CPU_HEADER */
diff --git a/lib/i386/relocator.c b/lib/i386/relocator.c
new file mode 100644
index 0000000..6a9b3ce
--- /dev/null
+++ b/lib/i386/relocator.c
@@ -0,0 +1,154 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2009  Free Software Foundation, Inc.
+ *
+ *  GRUB 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 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/mm.h>
+#include <grub/misc.h>
+
+#include <grub/types.h>
+#include <grub/types.h>
+#include <grub/err.h>
+
+#include <grub/i386/relocator.h>
+
+extern grub_uint8_t grub_relocator32_forward_start;
+extern grub_uint8_t grub_relocator32_forward_end;
+extern grub_uint8_t grub_relocator32_backward_start;
+extern grub_uint8_t grub_relocator32_backward_end;
+
+extern grub_uint32_t grub_relocator32_backward_dest;
+extern grub_uint32_t grub_relocator32_backward_size;
+#ifdef __x86_64__
+extern grub_uint64_t grub_relocator32_backward_src;
+#else
+extern grub_uint32_t grub_relocator32_backward_src;
+#endif
+
+extern grub_uint32_t grub_relocator32_forward_dest;
+extern grub_uint32_t grub_relocator32_forward_size;
+#ifdef __x86_64__
+extern grub_uint64_t grub_relocator32_forward_src;
+#else
+extern grub_uint32_t grub_relocator32_forward_src;
+#endif
+
+extern grub_uint32_t grub_relocator32_forward_eax;
+extern grub_uint32_t grub_relocator32_forward_ebx;
+extern grub_uint32_t grub_relocator32_forward_ecx;
+extern grub_uint32_t grub_relocator32_forward_edx;
+extern grub_uint32_t grub_relocator32_forward_eip;
+extern grub_uint32_t grub_relocator32_forward_esp;
+
+extern grub_uint32_t grub_relocator32_backward_eax;
+extern grub_uint32_t grub_relocator32_backward_ebx;
+extern grub_uint32_t grub_relocator32_backward_ecx;
+extern grub_uint32_t grub_relocator32_backward_edx;
+extern grub_uint32_t grub_relocator32_backward_eip;
+extern grub_uint32_t grub_relocator32_backward_esp;
+
+#define RELOCATOR_SIZEOF(x)	(&grub_relocator32_##x##_end - &grub_relocator32_##x##_start)
+#define RELOCATOR_ALIGN 16
+
+void *
+grub_relocator32_alloc (grub_size_t size)
+{
+  char *playground;
+
+  playground = grub_malloc ((RELOCATOR_SIZEOF (forward) + RELOCATOR_ALIGN)
+			    + size
+			    + (RELOCATOR_SIZEOF (backward) +
+			       RELOCATOR_ALIGN));
+  if (!playground)
+    return 0;
+
+  *(grub_size_t *) playground = size;
+
+  return playground + RELOCATOR_SIZEOF (forward);
+}
+
+void
+grub_relocator32_free (void *relocator)
+{
+  if (relocator)
+    grub_free ((char *) relocator - RELOCATOR_SIZEOF (forward));
+}
+
+
+grub_err_t
+grub_relocator32_boot (void *relocator, grub_uint32_t dest,
+		       struct grub_relocator32_state state)
+{
+  grub_size_t size;
+  char *playground;
+  void (*entry) ();
+
+  playground = (char *) relocator - RELOCATOR_SIZEOF (forward);
+  size = *(grub_size_t *) playground;
+
+  if (UINT_TO_PTR (dest) >= relocator)
+    {
+      int overhead;
+
+      overhead =
+	ALIGN_UP (dest - RELOCATOR_SIZEOF (backward) - RELOCATOR_ALIGN,
+		  RELOCATOR_ALIGN);
+      grub_relocator32_backward_dest = dest - overhead;
+      grub_relocator32_backward_src = PTR_TO_UINT64 (relocator - overhead);
+      grub_relocator32_backward_size = size + overhead;
+
+      grub_relocator32_backward_eax = state.eax;
+      grub_relocator32_backward_ebx = state.ebx;
+      grub_relocator32_backward_ecx = state.ecx;
+      grub_relocator32_backward_edx = state.edx;
+      grub_relocator32_backward_eip = state.eip;
+      grub_relocator32_backward_esp = state.esp;
+
+      grub_memmove (relocator - overhead,
+		    &grub_relocator32_backward_start,
+		    RELOCATOR_SIZEOF (backward));
+      entry = (void (*)()) (relocator - overhead);
+    }
+  else
+    {
+      int overhead;
+
+      overhead = ALIGN_UP (dest + size, RELOCATOR_ALIGN)
+	+ RELOCATOR_SIZEOF (forward) - (dest + size);
+
+      grub_relocator32_forward_dest = dest;
+      grub_relocator32_forward_src = PTR_TO_UINT64 (relocator);
+      grub_relocator32_forward_size = size + overhead;
+
+      grub_relocator32_forward_eax = state.eax;
+      grub_relocator32_forward_ebx = state.ebx;
+      grub_relocator32_forward_ecx = state.ecx;
+      grub_relocator32_forward_edx = state.edx;
+      grub_relocator32_forward_eip = state.eip;
+      grub_relocator32_forward_esp = state.esp;
+
+      grub_memmove (relocator + size + overhead - RELOCATOR_SIZEOF (forward),
+		    &grub_relocator32_forward_start,
+		    RELOCATOR_SIZEOF (forward));
+      entry =
+	(void (*)()) (relocator + size + overhead -
+		      RELOCATOR_SIZEOF (forward));
+    }
+  entry ();
+
+  /* Not reached.  */
+  return GRUB_ERR_NONE;
+}
diff --git a/lib/i386/relocator_asm.S b/lib/i386/relocator_asm.S
new file mode 100644
index 0000000..d022a68
--- /dev/null
+++ b/lib/i386/relocator_asm.S
@@ -0,0 +1,273 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2009  Free Software Foundation, Inc.
+ *
+ *  GRUB 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 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/symbol.h>
+
+#ifdef BACKWARD
+#define RELOCATOR_VARIABLE(x) VARIABLE(grub_relocator32_backward_ ## x)
+#else
+#define RELOCATOR_VARIABLE(x) VARIABLE(grub_relocator32_forward_ ## x)
+#endif
+	.p2align	4	/* force 16-byte alignment */
+
+RELOCATOR_VARIABLE(start)
+#ifdef BACKWARD
+base:
+#endif
+	cli
+
+#ifndef __x86_64__
+	/* mov imm32, %eax */
+	.byte	0xb8
+RELOCATOR_VARIABLE(dest)
+	.long 0
+	mov %eax, %edi
+
+	/* mov imm32, %eax */
+	.byte	0xb8
+RELOCATOR_VARIABLE(src)
+	.long 0
+	mov %eax, %esi
+
+	/* mov imm32, %ecx */
+	.byte	0xb9
+RELOCATOR_VARIABLE(size)
+	.long 0
+	mov %edi, %eax
+#ifndef BACKWARD
+	add %ecx, %eax
+#endif
+	add $0x3, %ecx
+	shr $2, %ecx
+
+#ifdef BACKWARD
+	/* Backward movsl is implicitly off-by-four.  compensate that.  */
+	subl	$4,	%esi
+	subl	$4,	%edi
+
+	/* Backward copy.  */
+	std
+	addl	%ecx, %esi
+	addl	%ecx, %edi
+
+	rep
+	movsl
+
+#else
+	/* Forward copy.  */
+	cld
+	rep
+	movsl
+#endif
+	/* %eax contains now our new base.  */
+	mov %eax, %esi
+	add $(cont0 - base), %eax
+	jmp *%eax
+cont0:
+#else
+	xorq %rax, %rax
+
+	/* mov imm32, %eax */
+	.byte	0xb8
+RELOCATOR_VARIABLE(dest)
+	.long 0
+	mov %eax, %edi
+
+	/* mov imm64, %rax */
+	.byte	0x48
+	.byte	0xb8
+RELOCATOR_VARIABLE(src)
+	.long 0, 0
+	mov %rax, %rsi
+
+	xorq %rcx, %rcx
+	/* mov imm32, %ecx */
+	.byte	0xb9
+RELOCATOR_VARIABLE(size)
+	.long 0
+
+	mov %rdi, %rax
+#ifndef BACKWARD
+	add %rcx, %rax
+#endif
+	add $0x3, %rcx
+	shr $2, %rcx
+
+#ifdef BACKWARD
+	/* Backward movsl is implicitly off-by-four.  compensate that.  */
+	subq	$4,	%rsi
+	subq	$4,	%rdi
+
+	/* Backward copy.  */
+	std
+	addq	%rcx, %rsi
+	addq	%rcx, %rdi
+
+	rep
+	movsl
+
+#else
+	/* Forward copy.  */
+	cld
+	rep
+	movsl
+#endif
+
+	/* %rax contains now our new 'base'.  */
+	mov %rax, %rsi
+#ifdef APPLE_CC
+	add $(cont0 - base), %eax
+#else
+	add $(cont0 - base), %rax
+#endif
+	jmp *%rax
+cont0:
+#ifdef APPLE_CC
+	lea (cont1 - base) (%esi, 1), %eax
+	mov %eax, (jump_vector - base) (%esi, 1)
+
+	lea (gdt - base) (%esi, 1), %eax
+	mov %eax, (gdt_addr - base) (%esi, 1)
+
+	/* Switch to compatibility mode. */
+
+	lgdt (gdtdesc - base) (%esi, 1)
+
+	/* Update %cs. Thanks to David Miller for pointing this mistake out. */
+	ljmp *(jump_vector - base) (%esi,1)
+#else
+	lea (cont1 - base) (%rsi, 1), %rax
+	mov %eax, (jump_vector - base) (%rsi, 1)
+
+	lea (gdt - base) (%rsi, 1), %rax
+	mov %rax, (gdt_addr - base) (%rsi, 1)
+
+	/* Switch to compatibility mode. */
+
+	lgdt (gdtdesc - base) (%rsi, 1)
+
+	/* Update %cs. Thanks to David Miller for pointing this mistake out. */
+	ljmp *(jump_vector - base) (%rsi, 1)
+#endif
+
+cont1:
+	.code32
+
+	/* Update other registers. */
+	mov $0x18, %eax
+	mov %eax, %ds
+	mov %eax, %es
+	mov %eax, %fs
+	mov %eax, %gs
+	mov %eax, %ss
+
+	/* Disable paging. */
+	mov %cr0, %eax
+	and $0x7fffffff, %eax
+	mov %eax, %cr0
+
+	/* Disable amd64. */
+	mov $0xc0000080, %ecx
+	rdmsr
+	and $0xfffffeff, %eax
+	wrmsr
+
+	/* Turn off PAE. */
+	movl %cr4, %eax
+	and $0xffffffcf, %eax
+	mov %eax, %cr4
+
+	jmp cont2
+cont2:
+#endif
+	.code32
+
+	/* mov imm32, %eax */
+	.byte	0xb8
+RELOCATOR_VARIABLE (esp)
+	.long 0
+
+	movl %eax, %esp
+
+	/* mov imm32, %eax */
+	.byte	0xb8
+RELOCATOR_VARIABLE (eax)
+	.long 0
+
+	/* mov imm32, %ebx */
+	.byte	0xbb
+RELOCATOR_VARIABLE (ebx)
+	.long 0
+
+	/* mov imm32, %ecx */
+	.byte	0xb9
+RELOCATOR_VARIABLE (ecx)
+	.long 0
+
+	/* mov imm32, %edx */
+	.byte	0xba
+RELOCATOR_VARIABLE (edx)
+	.long 0
+
+	/* Cleared direction flag is of no problem with any current
+	   payload and makes this implementation easier.  */
+	cld
+
+	.byte 0xea
+RELOCATOR_VARIABLE (eip)
+	.long 0
+#ifdef __x86_64__
+	.word 0x10
+#else
+	.word 0x08
+#endif
+
+#ifdef __x86_64__
+	/* GDT. Copied from loader/i386/linux.c. */
+	.p2align 4
+gdt:
+	/* NULL.  */
+	.byte 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+
+	/* Reserved.  */
+	.byte 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+
+	/* Code segment.  */
+	.byte 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x9A, 0xCF, 0x00
+
+	/* Data segment.  */
+	.byte 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x92, 0xCF, 0x00
+
+gdtdesc:
+	.word 31
+gdt_addr:
+	/* Filled by the code. */
+	.quad 0
+
+	.p2align 4
+jump_vector:
+	/* Jump location. Is filled by the code */
+	.long 0
+	.long 0x10
+#endif
+
+#ifndef BACKWARD
+base:
+#endif
+
+RELOCATOR_VARIABLE(end)
diff --git a/lib/i386/relocator_backward.S b/lib/i386/relocator_backward.S
new file mode 100644
index 0000000..0691347
--- /dev/null
+++ b/lib/i386/relocator_backward.S
@@ -0,0 +1,2 @@
+#define BACKWARD
+#include "relocator_asm.S"

^ permalink raw reply related	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2009-08-08 13:12 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-08-03 12:06 [PATCH 1/2] Relocator framework Vladimir 'phcoder' Serbinenko
2009-08-03 12:39 ` Vladimir 'phcoder' Serbinenko
2009-08-04 20:52 ` Robert Millan
2009-08-05 10:18   ` Vladimir 'phcoder' Serbinenko
2009-08-07 11:06     ` Robert Millan
2009-08-07 11:16       ` Marco Gerards
2009-08-07 12:01         ` Vladimir 'phcoder' Serbinenko
2009-08-08  3:52           ` Pavel Roskin
2009-08-08 13:11             ` Vladimir 'phcoder' Serbinenko

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