arch/x86/um/stub_32.S

   1 #include <as-layout.h>
   2
   3 .section .__syscall_stub, "ax"
   4
   5         .globl batch_syscall_stub
   6 batch_syscall_stub:
   7         /* load pointer to first operation */
   8         mov     $(STUB_DATA+8), %esp
   9
  10 again:
  11         /* load length of additional data */
  12         mov     0x0(%esp), %eax
  13
  14         /* if(length == 0) : end of list */
  15         /* write possible 0 to header */
  16         mov     %eax, STUB_DATA+4
  17         cmpl    $0, %eax
  18         jz      done
  19
  20         /* save current pointer */
  21         mov     %esp, STUB_DATA+4
  22
  23         /* skip additional data */
  24         add     %eax, %esp
  25
  26         /* load syscall-# */
  27         pop     %eax
  28
  29         /* load syscall params */
  30         pop     %ebx
  31         pop     %ecx
  32         pop     %edx
  33         pop     %esi
  34         pop     %edi
  35         pop     %ebp
  36
  37         /* execute syscall */
  38         int     $0x80
  39
  40         /* check return value */
  41         pop     %ebx
  42         cmp     %ebx, %eax
  43         je      again
  44
  45 done:
  46         /* save return value */
  47         mov     %eax, STUB_DATA
  48
  49         /* stop */
  50         int3