*/
#include <linux/linkage.h>
-#include <asm/page.h>
+#include <asm/page_types.h>
#include <asm/kexec.h>
#include <asm/processor-flags.h>
*/
#define PTR(x) (x << 2)
-#define PAGE_ATTR 0x63 /* _PAGE_PRESENT|_PAGE_RW|_PAGE_ACCESSED|_PAGE_DIRTY */
-#define PAE_PGD_ATTR 0x01 /* _PAGE_PRESENT */
+
+/*
+ * control_page + KEXEC_CONTROL_CODE_MAX_SIZE
+ * ~ control_page + PAGE_SIZE are used as data storage and stack for
+ * jumping back
+ */
+#define DATA(offset) (KEXEC_CONTROL_CODE_MAX_SIZE+(offset))
+
+/* Minimal CPU state */
+#define ESP DATA(0x0)
+#define CR0 DATA(0x4)
+#define CR3 DATA(0x8)
+#define CR4 DATA(0xc)
+
+/* other data */
+#define CP_VA_CONTROL_PAGE DATA(0x10)
+#define CP_PA_PGD DATA(0x14)
+#define CP_PA_SWAP_PAGE DATA(0x18)
+#define CP_PA_BACKUP_PAGES_MAP DATA(0x1c)
.text
- .align PAGE_SIZE
.globl relocate_kernel
relocate_kernel:
- movl 8(%esp), %ebp /* list of pages */
-
-#ifdef CONFIG_X86_PAE
- /* map the control page at its virtual address */
-
- movl PTR(VA_PGD)(%ebp), %edi
- movl PTR(VA_CONTROL_PAGE)(%ebp), %eax
- andl $0xc0000000, %eax
- shrl $27, %eax
- addl %edi, %eax
-
- movl PTR(PA_PMD_0)(%ebp), %edx
- orl $PAE_PGD_ATTR, %edx
- movl %edx, (%eax)
-
- movl PTR(VA_PMD_0)(%ebp), %edi
- movl PTR(VA_CONTROL_PAGE)(%ebp), %eax
- andl $0x3fe00000, %eax
- shrl $18, %eax
- addl %edi, %eax
-
- movl PTR(PA_PTE_0)(%ebp), %edx
- orl $PAGE_ATTR, %edx
- movl %edx, (%eax)
-
- movl PTR(VA_PTE_0)(%ebp), %edi
- movl PTR(VA_CONTROL_PAGE)(%ebp), %eax
- andl $0x001ff000, %eax
- shrl $9, %eax
- addl %edi, %eax
-
- movl PTR(PA_CONTROL_PAGE)(%ebp), %edx
- orl $PAGE_ATTR, %edx
- movl %edx, (%eax)
-
- /* identity map the control page at its physical address */
-
- movl PTR(VA_PGD)(%ebp), %edi
- movl PTR(PA_CONTROL_PAGE)(%ebp), %eax
- andl $0xc0000000, %eax
- shrl $27, %eax
- addl %edi, %eax
-
- movl PTR(PA_PMD_1)(%ebp), %edx
- orl $PAE_PGD_ATTR, %edx
- movl %edx, (%eax)
-
- movl PTR(VA_PMD_1)(%ebp), %edi
- movl PTR(PA_CONTROL_PAGE)(%ebp), %eax
- andl $0x3fe00000, %eax
- shrl $18, %eax
- addl %edi, %eax
-
- movl PTR(PA_PTE_1)(%ebp), %edx
- orl $PAGE_ATTR, %edx
- movl %edx, (%eax)
-
- movl PTR(VA_PTE_1)(%ebp), %edi
- movl PTR(PA_CONTROL_PAGE)(%ebp), %eax
- andl $0x001ff000, %eax
- shrl $9, %eax
- addl %edi, %eax
-
- movl PTR(PA_CONTROL_PAGE)(%ebp), %edx
- orl $PAGE_ATTR, %edx
- movl %edx, (%eax)
-#else
- /* map the control page at its virtual address */
-
- movl PTR(VA_PGD)(%ebp), %edi
- movl PTR(VA_CONTROL_PAGE)(%ebp), %eax
- andl $0xffc00000, %eax
- shrl $20, %eax
- addl %edi, %eax
-
- movl PTR(PA_PTE_0)(%ebp), %edx
- orl $PAGE_ATTR, %edx
- movl %edx, (%eax)
-
- movl PTR(VA_PTE_0)(%ebp), %edi
- movl PTR(VA_CONTROL_PAGE)(%ebp), %eax
- andl $0x003ff000, %eax
- shrl $10, %eax
- addl %edi, %eax
-
- movl PTR(PA_CONTROL_PAGE)(%ebp), %edx
- orl $PAGE_ATTR, %edx
- movl %edx, (%eax)
-
- /* identity map the control page at its physical address */
-
- movl PTR(VA_PGD)(%ebp), %edi
- movl PTR(PA_CONTROL_PAGE)(%ebp), %eax
- andl $0xffc00000, %eax
- shrl $20, %eax
- addl %edi, %eax
-
- movl PTR(PA_PTE_1)(%ebp), %edx
- orl $PAGE_ATTR, %edx
- movl %edx, (%eax)
-
- movl PTR(VA_PTE_1)(%ebp), %edi
- movl PTR(PA_CONTROL_PAGE)(%ebp), %eax
- andl $0x003ff000, %eax
- shrl $10, %eax
- addl %edi, %eax
-
- movl PTR(PA_CONTROL_PAGE)(%ebp), %edx
- orl $PAGE_ATTR, %edx
- movl %edx, (%eax)
-#endif
-
-relocate_new_kernel:
+ /* Save the CPU context, used for jumping back */
+
+ pushl %ebx
+ pushl %esi
+ pushl %edi
+ pushl %ebp
+ pushf
+
+ movl 20+8(%esp), %ebp /* list of pages */
+ movl PTR(VA_CONTROL_PAGE)(%ebp), %edi
+ movl %esp, ESP(%edi)
+ movl %cr0, %eax
+ movl %eax, CR0(%edi)
+ movl %cr3, %eax
+ movl %eax, CR3(%edi)
+ movl %cr4, %eax
+ movl %eax, CR4(%edi)
+
/* read the arguments and say goodbye to the stack */
- movl 4(%esp), %ebx /* page_list */
- movl 8(%esp), %ebp /* list of pages */
- movl 12(%esp), %edx /* start address */
- movl 16(%esp), %ecx /* cpu_has_pae */
+ movl 20+4(%esp), %ebx /* page_list */
+ movl 20+8(%esp), %ebp /* list of pages */
+ movl 20+12(%esp), %edx /* start address */
+ movl 20+16(%esp), %ecx /* cpu_has_pae */
+ movl 20+20(%esp), %esi /* preserve_context */
/* zero out flags, and disable interrupts */
pushl $0
popfl
- /* get physical address of control page now */
- /* this is impossible after page table switch */
+ /* save some information for jumping back */
+ movl PTR(VA_CONTROL_PAGE)(%ebp), %edi
+ movl %edi, CP_VA_CONTROL_PAGE(%edi)
+ movl PTR(PA_PGD)(%ebp), %eax
+ movl %eax, CP_PA_PGD(%edi)
+ movl PTR(PA_SWAP_PAGE)(%ebp), %eax
+ movl %eax, CP_PA_SWAP_PAGE(%edi)
+ movl %ebx, CP_PA_BACKUP_PAGES_MAP(%edi)
+
+ /*
+ * get physical address of control page now
+ * this is impossible after page table switch
+ */
movl PTR(PA_CONTROL_PAGE)(%ebp), %edi
/* switch to new set of page tables */
/* store the start address on the stack */
pushl %edx
- /* Set cr0 to a known state:
+ /*
+ * Set cr0 to a known state:
* - Paging disabled
* - Alignment check disabled
* - Write protect disabled
/* clear cr4 if applicable */
testl %ecx, %ecx
jz 1f
- /* Set cr4 to a known state:
+ /*
+ * Set cr4 to a known state:
* Setting everything to zero seems safe.
*/
xorl %eax, %eax
xorl %eax, %eax
movl %eax, %cr3
+ movl CP_PA_SWAP_PAGE(%edi), %eax
+ pushl %eax
+ pushl %ebx
+ call swap_pages
+ addl $8, %esp
+
+ /*
+ * To be certain of avoiding problems with self-modifying code
+ * I need to execute a serializing instruction here.
+ * So I flush the TLB, it's handy, and not processor dependent.
+ */
+ xorl %eax, %eax
+ movl %eax, %cr3
+
+ /*
+ * set all of the registers to known values
+ * leave %esp alone
+ */
+
+ testl %esi, %esi
+ jnz 1f
+ xorl %edi, %edi
+ xorl %eax, %eax
+ xorl %ebx, %ebx
+ xorl %ecx, %ecx
+ xorl %edx, %edx
+ xorl %esi, %esi
+ xorl %ebp, %ebp
+ ret
+1:
+ popl %edx
+ movl CP_PA_SWAP_PAGE(%edi), %esp
+ addl $PAGE_SIZE, %esp
+2:
+ call *%edx
+
+ /* get the re-entry point of the peer system */
+ movl 0(%esp), %ebp
+ call 1f
+1:
+ popl %ebx
+ subl $(1b - relocate_kernel), %ebx
+ movl CP_VA_CONTROL_PAGE(%ebx), %edi
+ lea PAGE_SIZE(%ebx), %esp
+ movl CP_PA_SWAP_PAGE(%ebx), %eax
+ movl CP_PA_BACKUP_PAGES_MAP(%ebx), %edx
+ pushl %eax
+ pushl %edx
+ call swap_pages
+ addl $8, %esp
+ movl CP_PA_PGD(%ebx), %eax
+ movl %eax, %cr3
+ movl %cr0, %eax
+ orl $(1<<31), %eax
+ movl %eax, %cr0
+ lea PAGE_SIZE(%edi), %esp
+ movl %edi, %eax
+ addl $(virtual_mapped - relocate_kernel), %eax
+ pushl %eax
+ ret
+
+virtual_mapped:
+ movl CR4(%edi), %eax
+ movl %eax, %cr4
+ movl CR3(%edi), %eax
+ movl %eax, %cr3
+ movl CR0(%edi), %eax
+ movl %eax, %cr0
+ movl ESP(%edi), %esp
+ movl %ebp, %eax
+
+ popf
+ popl %ebp
+ popl %edi
+ popl %esi
+ popl %ebx
+ ret
+
/* Do the copies */
- movl %ebx, %ecx
+swap_pages:
+ movl 8(%esp), %edx
+ movl 4(%esp), %ecx
+ pushl %ebp
+ pushl %ebx
+ pushl %edi
+ pushl %esi
+ movl %ecx, %ebx
jmp 1f
0: /* top, read another word from the indirection page */
movl %ecx, %esi /* For every source page do a copy */
andl $0xfffff000, %esi
+ movl %edi, %eax
+ movl %esi, %ebp
+
+ movl %edx, %edi
movl $1024, %ecx
rep ; movsl
- jmp 0b
-
-3:
- /* To be certain of avoiding problems with self-modifying code
- * I need to execute a serializing instruction here.
- * So I flush the TLB, it's handy, and not processor dependent.
- */
- xorl %eax, %eax
- movl %eax, %cr3
+ movl %ebp, %edi
+ movl %eax, %esi
+ movl $1024, %ecx
+ rep ; movsl
- /* set all of the registers to known values */
- /* leave %esp alone */
+ movl %eax, %edi
+ movl %edx, %esi
+ movl $1024, %ecx
+ rep ; movsl
- xorl %eax, %eax
- xorl %ebx, %ebx
- xorl %ecx, %ecx
- xorl %edx, %edx
- xorl %esi, %esi
- xorl %edi, %edi
- xorl %ebp, %ebp
+ lea PAGE_SIZE(%ebp), %esi
+ jmp 0b
+3:
+ popl %esi
+ popl %edi
+ popl %ebx
+ popl %ebp
ret
+
+ .globl kexec_control_code_size
+.set kexec_control_code_size, . - relocate_kernel
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff