static inline struct extended_bios_data_area_s *
get_ebda_ptr()
{
- ASSERT32();
+ ASSERT32FLAT();
return MAKE_FLATPTR(get_ebda_seg(), 0);
}
#define GET_EBDA2(eseg, var) \
* Global variables
****************************************************************/
+#if MODE16 == 0 && MODESEGMENT == 1
+// In 32bit segmented mode %cs may not be readable and the code may be
+// relocated. The entry code sets up %gs with a readable segment and
+// the code offset can be determined by get_global_offset().
+#define GLOBAL_SEGREG GS
+static inline u32 __attribute_const get_global_offset(void) {
+ u32 ret;
+ asm(" calll 1f\n"
+ "1:popl %0\n"
+ " subl $1b, %0"
+ : "=r"(ret));
+ return ret;
+}
+#else
#define GLOBAL_SEGREG CS
+static inline u32 __attribute_const get_global_offset(void) {
+ return 0;
+}
+#endif
static inline u16 get_global_seg() {
return GET_SEG(GLOBAL_SEGREG);
}
-#define GET_GLOBAL(var) \
- GET_VAR(GLOBAL_SEGREG, (var))
+#define GET_GLOBAL(var) \
+ GET_VAR(GLOBAL_SEGREG, *(typeof(&(var)))((void*)&(var) \
+ + get_global_offset()))
#define SET_GLOBAL(var, val) do { \
- ASSERT32(); \
+ ASSERT32FLAT(); \
(var) = (val); \
} while (0)
-#if MODE16
+#if MODESEGMENT
#define ADJUST_GLOBAL_PTR(var) (var)
#else
#define ADJUST_GLOBAL_PTR(var) ((typeof(var))((void*)var - BUILD_BIOS_ADDR))