lunaix-os/arch/x86/hart32.c

   1 #ifdef CONFIG_ARCH_I386
   2
   3 #include <lunaix/process.h>
   4 #include <lunaix/hart_state.h>
   5 #include <lunaix/mm/vmm.h>
   6 #include <klibc/string.h>
   7
   8 #include <asm/mempart.h>
   9 #include <asm/abi.h>
  10
  11 volatile struct x86_tss _tss = { .link = 0,
  12                                  .esp0 = 0,
  13                                  .ss0 = KDATA_SEG };
  14
  15 void
  16 hart_prepare_transition(struct hart_transition* ht,
  17                       ptr_t kstack_tp, ptr_t ustack_pt,
  18                       ptr_t entry, bool to_user)
  19 {
  20     ptr_t offset = (ptr_t)&ht->transfer.eret - (ptr_t)&ht->transfer;
  21     ht->inject = align_stack(kstack_tp - sizeof(ht->transfer));
  22
  23     ht->transfer.state = (struct hart_state){
  24                             .registers = {
  25                                 .ds = KDATA_SEG,
  26                                 .es = KDATA_SEG,
  27                                 .fs = KDATA_SEG,
  28                                 .gs = KDATA_SEG
  29                             },
  30                             .execp = (struct exec_param*)(ht->inject + offset)
  31                         };
  32
  33     int code_seg = KCODE_SEG, data_seg = KDATA_SEG;
  34     int mstate = cpu_ldstate();
  35     if (to_user) {
  36         code_seg = UCODE_SEG, data_seg = UDATA_SEG;
  37         mstate |= 0x200;   // enable interrupt
  38     }
  39
  40     ht->transfer.eret = (struct exec_param) {
  41                             .cs = code_seg, .eip = entry,
  42                             .ss = data_seg, .esp = align_stack(ustack_pt),
  43                             .eflags = mstate
  44                         };
  45 }
  46
  47 #endif