blob: ae056e553d1365989aef36c87fa4e898312518a3 [file] [log] [blame]
/*
* Code for the vsyscall page. This version uses the sysenter instruction.
*/
#include <asm/ia32_unistd.h>
#include <asm/asm-offsets.h>
.code32
.text
.section .text.vsyscall,"ax"
.globl __kernel_vsyscall
.type __kernel_vsyscall,@function
__kernel_vsyscall:
.LSTART_vsyscall:
push %ecx
.Lpush_ecx:
push %edx
.Lpush_edx:
push %ebp
.Lenter_kernel:
movl %esp,%ebp
sysenter
.space 7,0x90
jmp .Lenter_kernel
/* 16: System call normal return point is here! */
pop %ebp
.Lpop_ebp:
pop %edx
.Lpop_edx:
pop %ecx
.Lpop_ecx:
ret
.LEND_vsyscall:
.size __kernel_vsyscall,.-.LSTART_vsyscall
.section .eh_frame,"a",@progbits
.LSTARTFRAME:
.long .LENDCIE-.LSTARTCIE
.LSTARTCIE:
.long 0 /* CIE ID */
.byte 1 /* Version number */
.string "zR" /* NUL-terminated augmentation string */
.uleb128 1 /* Code alignment factor */
.sleb128 -4 /* Data alignment factor */
.byte 8 /* Return address register column */
.uleb128 1 /* Augmentation value length */
.byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
.byte 0x0c /* DW_CFA_def_cfa */
.uleb128 4
.uleb128 4
.byte 0x88 /* DW_CFA_offset, column 0x8 */
.uleb128 1
.align 4
.LENDCIE:
.long .LENDFDE1-.LSTARTFDE1 /* Length FDE */
.LSTARTFDE1:
.long .LSTARTFDE1-.LSTARTFRAME /* CIE pointer */
.long .LSTART_vsyscall-. /* PC-relative start address */
.long .LEND_vsyscall-.LSTART_vsyscall
.uleb128 0 /* Augmentation length */
/* What follows are the instructions for the table generation.
We have to record all changes of the stack pointer. */
.byte 0x04 /* DW_CFA_advance_loc4 */
.long .Lpush_ecx-.LSTART_vsyscall
.byte 0x0e /* DW_CFA_def_cfa_offset */
.byte 0x08 /* RA at offset 8 now */
.byte 0x04 /* DW_CFA_advance_loc4 */
.long .Lpush_edx-.Lpush_ecx
.byte 0x0e /* DW_CFA_def_cfa_offset */
.byte 0x0c /* RA at offset 12 now */
.byte 0x04 /* DW_CFA_advance_loc4 */
.long .Lenter_kernel-.Lpush_edx
.byte 0x0e /* DW_CFA_def_cfa_offset */
.byte 0x10 /* RA at offset 16 now */
.byte 0x85, 0x04 /* DW_CFA_offset %ebp -16 */
/* Finally the epilogue. */
.byte 0x04 /* DW_CFA_advance_loc4 */
.long .Lpop_ebp-.Lenter_kernel
.byte 0x0e /* DW_CFA_def_cfa_offset */
.byte 0x12 /* RA at offset 12 now */
.byte 0xc5 /* DW_CFA_restore %ebp */
.byte 0x04 /* DW_CFA_advance_loc4 */
.long .Lpop_edx-.Lpop_ebp
.byte 0x0e /* DW_CFA_def_cfa_offset */
.byte 0x08 /* RA at offset 8 now */
.byte 0x04 /* DW_CFA_advance_loc4 */
.long .Lpop_ecx-.Lpop_edx
.byte 0x0e /* DW_CFA_def_cfa_offset */
.byte 0x04 /* RA at offset 4 now */
.align 4
.LENDFDE1:
#define SYSCALL_ENTER_KERNEL int $0x80
#include "vsyscall-sigreturn.S"