| /* |
| * 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" |