/*
* relocate_kernel.S - put the kernel image in place to boot
- * Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com>
+ * Copyright (C) 2002-2005 Eric Biederman <ebiederm@xmission.com>
*
* This source code is licensed under the GNU General Public License,
* Version 2. See the file COPYING for more details.
*/
#include <linux/linkage.h>
+#include <asm/page.h>
+#include <asm/kexec.h>
- /*
- * Must be relocatable PIC code callable as a C function, that once
- * it starts can not use the previous processes stack.
- */
- .globl relocate_new_kernel
+/*
+ * Must be relocatable PIC code callable as a C function
+ */
+
+#define PTR(x) (x << 3)
+#define PAGE_ALIGNED (1 << PAGE_SHIFT)
+#define PAGE_ATTR 0x63 /* _PAGE_PRESENT|_PAGE_RW|_PAGE_ACCESSED|_PAGE_DIRTY */
+
+ .text
+ .align PAGE_ALIGNED
.code64
+ .globl relocate_kernel
+relocate_kernel:
+ /* %rdi indirection_page
+ * %rsi page_list
+ * %rdx start address
+ */
+
+ /* map the control page at its virtual address */
+
+ movq $0x0000ff8000000000, %r10 /* mask */
+ mov $(39 - 3), %cl /* bits to shift */
+ movq PTR(VA_CONTROL_PAGE)(%rsi), %r11 /* address to map */
+
+ movq %r11, %r9
+ andq %r10, %r9
+ shrq %cl, %r9
+
+ movq PTR(VA_PGD)(%rsi), %r8
+ addq %r8, %r9
+ movq PTR(PA_PUD_0)(%rsi), %r8
+ orq $PAGE_ATTR, %r8
+ movq %r8, (%r9)
+
+ shrq $9, %r10
+ sub $9, %cl
+
+ movq %r11, %r9
+ andq %r10, %r9
+ shrq %cl, %r9
+
+ movq PTR(VA_PUD_0)(%rsi), %r8
+ addq %r8, %r9
+ movq PTR(PA_PMD_0)(%rsi), %r8
+ orq $PAGE_ATTR, %r8
+ movq %r8, (%r9)
+
+ shrq $9, %r10
+ sub $9, %cl
+
+ movq %r11, %r9
+ andq %r10, %r9
+ shrq %cl, %r9
+
+ movq PTR(VA_PMD_0)(%rsi), %r8
+ addq %r8, %r9
+ movq PTR(PA_PTE_0)(%rsi), %r8
+ orq $PAGE_ATTR, %r8
+ movq %r8, (%r9)
+
+ shrq $9, %r10
+ sub $9, %cl
+
+ movq %r11, %r9
+ andq %r10, %r9
+ shrq %cl, %r9
+
+ movq PTR(VA_PTE_0)(%rsi), %r8
+ addq %r8, %r9
+ movq PTR(PA_CONTROL_PAGE)(%rsi), %r8
+ orq $PAGE_ATTR, %r8
+ movq %r8, (%r9)
+
+ /* identity map the control page at its physical address */
+
+ movq $0x0000ff8000000000, %r10 /* mask */
+ mov $(39 - 3), %cl /* bits to shift */
+ movq PTR(PA_CONTROL_PAGE)(%rsi), %r11 /* address to map */
+
+ movq %r11, %r9
+ andq %r10, %r9
+ shrq %cl, %r9
+
+ movq PTR(VA_PGD)(%rsi), %r8
+ addq %r8, %r9
+ movq PTR(PA_PUD_1)(%rsi), %r8
+ orq $PAGE_ATTR, %r8
+ movq %r8, (%r9)
+
+ shrq $9, %r10
+ sub $9, %cl
+
+ movq %r11, %r9
+ andq %r10, %r9
+ shrq %cl, %r9
+
+ movq PTR(VA_PUD_1)(%rsi), %r8
+ addq %r8, %r9
+ movq PTR(PA_PMD_1)(%rsi), %r8
+ orq $PAGE_ATTR, %r8
+ movq %r8, (%r9)
+
+ shrq $9, %r10
+ sub $9, %cl
+
+ movq %r11, %r9
+ andq %r10, %r9
+ shrq %cl, %r9
+
+ movq PTR(VA_PMD_1)(%rsi), %r8
+ addq %r8, %r9
+ movq PTR(PA_PTE_1)(%rsi), %r8
+ orq $PAGE_ATTR, %r8
+ movq %r8, (%r9)
+
+ shrq $9, %r10
+ sub $9, %cl
+
+ movq %r11, %r9
+ andq %r10, %r9
+ shrq %cl, %r9
+
+ movq PTR(VA_PTE_1)(%rsi), %r8
+ addq %r8, %r9
+ movq PTR(PA_CONTROL_PAGE)(%rsi), %r8
+ orq $PAGE_ATTR, %r8
+ movq %r8, (%r9)
+
relocate_new_kernel:
/* %rdi indirection_page
- * %rsi reboot_code_buffer
+ * %rsi page_list
* %rdx start address
- * %rcx page_table
- * %r8 arg5
- * %r9 arg6
*/
/* zero out flags, and disable interrupts */
pushq $0
popfq
- /* set a new stack at the bottom of our page... */
- lea 4096(%rsi), %rsp
+ /* get physical address of control page now */
+ /* this is impossible after page table switch */
+ movq PTR(PA_CONTROL_PAGE)(%rsi), %r8
+
+ /* get physical address of page table now too */
+ movq PTR(PA_TABLE_PAGE)(%rsi), %rcx
+
+ /* switch to new set of page tables */
+ movq PTR(PA_PGD)(%rsi), %r9
+ movq %r9, %cr3
- /* store the parameters back on the stack */
- pushq %rdx /* store the start address */
+ /* setup a new stack at the end of the physical control page */
+ lea 4096(%r8), %rsp
+
+ /* jump to identity mapped page */
+ addq $(identity_mapped - relocate_kernel), %r8
+ pushq %r8
+ ret
+
+identity_mapped:
+ /* store the start address on the stack */
+ pushq %rdx
/* Set cr0 to a known state:
* 31 1 == Paging enabled
movq %rcx, %cr3
/* Do the copies */
- movq %rdi, %rbx /* Put the indirection page in %rbx */
+ movq %rdi, %rcx /* Put the page_list in %rcx */
xorq %rdi, %rdi
xorq %rsi, %rsi
+ jmp 1f
0: /* top, read another word for the indirection page */
movq (%rbx), %rcx
addq $8, %rbx
+1:
testq $0x1, %rcx /* is it a destination page? */
- jz 1f
+ jz 2f
movq %rcx, %rdi
andq $0xfffffffffffff000, %rdi
jmp 0b
-1:
+2:
testq $0x2, %rcx /* is it an indirection page? */
- jz 1f
+ jz 2f
movq %rcx, %rbx
andq $0xfffffffffffff000, %rbx
jmp 0b
-1:
+2:
testq $0x4, %rcx /* is it the done indicator? */
- jz 1f
- jmp 2f
-1:
+ jz 2f
+ jmp 3f
+2:
testq $0x8, %rcx /* is it the source indicator? */
jz 0b /* Ignore it otherwise */
movq %rcx, %rsi /* For ever source page do a copy */
movq $512, %rcx
rep ; movsq
jmp 0b
-2:
+3:
/* To be certain of avoiding problems with self-modifying code
* I need to execute a serializing instruction here.
xorq %r15, %r15
ret
-relocate_new_kernel_end:
-
- .globl relocate_new_kernel_size
-relocate_new_kernel_size:
- .quad relocate_new_kernel_end - relocate_new_kernel