sys/i386/linux/linux_locore.s

   1 /* $FreeBSD$ */
   2
   3 #include "linux_assym.h"                        /* system definitions */
   4 #include <machine/asmacros.h>                   /* miscellaneous asm macros */
   5
   6 #include <i386/linux/linux_syscall.h>           /* system call numbers */
   7
   8 #include "assym.s"
   9
  10 /*
  11  * To avoid excess stack frame the signal trampoline code emulates
  12  * the 'call' instruction.
  13  */
  14 NON_GPROF_ENTRY(linux_sigcode)
  15         movl    %esp, %ebx                      /* preserve sigframe */
  16         call .getip0
  17 .getip0:
  18         popl    %eax
  19         add     $.startsigcode-.getip0, %eax    /* ret address */
  20         push    %eax
  21         jmp     *LINUX_SIGF_HANDLER(%ebx)
  22 .startsigcode:
  23         popl    %eax                            /* gcc unwind code need this */
  24         movl    $LINUX_SYS_linux_sigreturn,%eax /* linux_sigreturn() */
  25         int     $0x80                           /* enter kernel with args */
  26 .endsigcode:
  27 0:      jmp     0b
  28
  29 NON_GPROF_ENTRY(linux_rt_sigcode)
  30         leal    LINUX_RT_SIGF_UC(%esp),%ebx     /* linux ucp */
  31         leal    LINUX_RT_SIGF_SC(%ebx),%ecx     /* linux sigcontext */
  32         movl    %esp, %edi
  33         call    .getip1
  34 .getip1:
  35         popl    %eax
  36         add     $.startrtsigcode-.getip1, %eax  /* ret address */
  37         push    %eax
  38         jmp     *LINUX_RT_SIGF_HANDLER(%edi)
  39 .startrtsigcode:
  40         movl    $LINUX_SYS_linux_rt_sigreturn,%eax   /* linux_rt_sigreturn() */
  41         int     $0x80                           /* enter kernel with args */
  42 .endrtsigcode:
  43 0:      jmp     0b
  44
  45 NON_GPROF_ENTRY(linux_vsyscall)
  46 .startvsyscall:
  47         int $0x80
  48         ret
  49 .endvsyscall:
  50
  51 #if 0
  52         .section .note.Linux, "a",@note
  53         .long 2f - 1f           /* namesz */
  54         .balign 4
  55         .long 4f - 3f           /* descsz */
  56         .long 0
  57 1:
  58         .asciz "Linux"
  59 2:
  60         .balign 4
  61 3:
  62         .long LINUX_VERSION_CODE
  63 4:
  64         .balign 4
  65         .previous
  66 #endif
  67
  68 #define do_cfa_expr(offset)                                             \
  69         .byte 0x0f;                     /* DW_CFA_def_cfa_expression */ \
  70         .uleb128 11f-10f;               /*   length */                  \
  71 10:     .byte 0x74;                     /*     DW_OP_breg4 */           \
  72         .sleb128 offset;                /*      offset */               \
  73         .byte 0x06;                     /*     DW_OP_deref */           \
  74 11:
  75
  76
  77         /* CIE */
  78         .section .eh_frame,"a",@progbits
  79 .LSTARTFRAMEDLSI1:
  80         .long .LENDCIEDLSI1-.LSTARTCIEDLSI1
  81 .LSTARTCIEDLSI1:
  82         .long 0                                 /* CIE ID */
  83         .byte 1                                 /* Version number */
  84         .string "zRS"                           /* NULL-terminated
  85                                                  * augmentation string
  86                                                  */
  87         .uleb128 1                              /* Code alignment factor */
  88         .sleb128 -4                             /* Data alignment factor */
  89         .byte 8                                 /* Return address
  90                                                  * register column
  91                                                  */
  92         .uleb128 1                              /* Augmentation value length */
  93         .byte 0x1b                              /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
  94         .byte 0                                 /* DW_CFA_nop */
  95         .align 4
  96 .LENDCIEDLSI1:
  97
  98         /* FDE */
  99         .long .LENDFDEDLSI1-.LSTARTFDEDLSI1     /* Length FDE */
 100 .LSTARTFDEDLSI1:
 101         .long .LSTARTFDEDLSI1-.LSTARTFRAMEDLSI1 /* CIE pointer */
 102         .long .startsigcode-.                   /* PC-relative start address */
 103         .long .endsigcode-.startsigcode
 104         .uleb128 0                              /* Augmentation */
 105         do_cfa_expr(LINUX_SIGF_SC-8)
 106         .align 4
 107 .LENDFDEDLSI1:
 108
 109         .long .LENDFDEDLSI2-.LSTARTFDEDLSI2     /* Length FDE */
 110 .LSTARTFDEDLSI2:
 111         .long .LSTARTFDEDLSI2-.LSTARTFRAMEDLSI1 /* CIE pointer */
 112         .long .startrtsigcode-.                 /* PC-relative start address */
 113         .long .endrtsigcode-.startrtsigcode
 114         .uleb128 0                              /* Augmentation */
 115         do_cfa_expr(LINUX_RT_SIGF_SC-4+LINUX_SC_ESP)
 116         .align 4
 117 .LENDFDEDLSI2:
 118         .previous
 119
 120         .section .eh_frame,"a",@progbits
 121 .LSTARTFRAMEDLSI2:
 122         .long .LENDCIEDLSI2-.LSTARTCIEDLSI2
 123 .LSTARTCIEDLSI2:
 124         .long 0                                 /* CIE ID */
 125         .byte 1                                 /* Version number */
 126         .string "zR"                            /* NULL-terminated
 127                                                  * augmentation string
 128                                                  */
 129         .uleb128 1                              /* Code alignment factor */
 130         .sleb128 -4                             /* Data alignment factor */
 131         .byte 8                                 /* Return address register column */
 132         .uleb128 1                              /* Augmentation value length */
 133         .byte 0x1b                              /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
 134         .byte 0x0c                              /* DW_CFA_def_cfa */
 135         .uleb128 4
 136         .uleb128 4
 137         .byte 0x88                              /* DW_CFA_offset, column 0x8 */
 138         .uleb128 1
 139         .align 4
 140 .LENDCIEDLSI2:
 141         .long .LENDFDEDLSI3-.LSTARTFDEDLSI3 /* Length FDE */
 142 .LSTARTFDEDLSI3:
 143         .long .LSTARTFDEDLSI3-.LSTARTFRAMEDLSI2 /* CIE pointer */
 144         .long .startvsyscall-.                  /* PC-relative start address */
 145         .long .endvsyscall-.startvsyscall
 146         .uleb128 0
 147         .align 4
 148 .LENDFDEDLSI3:
 149         .previous