vendor/dlmalloc/src/sgx.rs

   1 use core::ptr;
   2 use core::sync::atomic::{AtomicBool, Ordering, ATOMIC_BOOL_INIT};
   3
   4 // Do not remove inline: will result in relocation failure
   5 #[inline(always)]
   6 unsafe fn rel_ptr_mut<T>(offset: u64) -> *mut T {
   7     (image_base() + offset) as *mut T
   8 }
   9
  10 // Do not remove inline: will result in relocation failure
  11 // For the same reason we use inline ASM here instead of an extern static to
  12 // locate the base
  13 #[inline(always)]
  14 fn image_base() -> u64 {
  15     let base;
  16     unsafe { llvm_asm!("lea IMAGE_BASE(%rip),$0":"=r"(base)) };
  17     base
  18 }
  19
  20 pub unsafe fn alloc(_size: usize) -> (*mut u8, usize, u32) {
  21     extern "C" {
  22         static HEAP_BASE: u64;
  23         static HEAP_SIZE: usize;
  24     }
  25     static INIT: AtomicBool = ATOMIC_BOOL_INIT;
  26     // No ordering requirement since this function is protected by the global lock.
  27     if !INIT.swap(true, Ordering::Relaxed) {
  28         (rel_ptr_mut(HEAP_BASE), HEAP_SIZE, 0)
  29     } else {
  30         (ptr::null_mut(), 0, 0)
  31     }
  32 }
  33
  34 pub unsafe fn remap(_ptr: *mut u8, _oldsize: usize, _newsize: usize, _can_move: bool) -> *mut u8 {
  35     ptr::null_mut()
  36 }
  37
  38 pub unsafe fn free_part(_ptr: *mut u8, _oldsize: usize, _newsize: usize) -> bool {
  39     false
  40 }
  41
  42 pub unsafe fn free(_ptr: *mut u8, _size: usize) -> bool {
  43     false
  44 }
  45
  46 pub fn can_release_part(_flags: u32) -> bool {
  47     false
  48 }
  49
  50 #[cfg(feature = "global")]
  51 pub fn acquire_global_lock() {
  52     compile_error!("The `global` feature is not implemented for the SGX platform")
  53 }
  54
  55 #[cfg(feature = "global")]
  56 pub fn release_global_lock() {
  57     compile_error!("The `global` feature is not implemented for the SGX platform")
  58 }
  59
  60 pub fn allocates_zeros() -> bool {
  61     false
  62 }
  63
  64 pub fn page_size() -> usize {
  65     0x1000
  66 }