kernel/usrspace.s


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global userspace_init
extern _binary_usrbin_bin_start
extern _binary_usrbin_bin_size

userspace_init:
  push ebp
  mov ebp, esp
  push esi
  push edi
  mov ecx, _binary_usrbin_bin_size
  mov esi, _binary_usrbin_bin_start
  mov edi, 0x100000
.loop:
  movsb
  dec ecx
  jz .end
  jmp .loop
.end:
  pop edi
  pop esi
  call usrcall
  pop ebp
  ret

usrcall:
  push ebp
  mov ebp, esp
  cli
  mov ax, 0x23
  mov ds, ax
  mov es, ax
  mov fs, ax
  mov gs, ax
  mov eax, esp
  push dword 0x23
  push eax
  pushf
  push dword 0x1B
  push dword 0x00100000
  iret
  pop ebp
  ret