libc/src/sys/mman/linux/remap_file_pages.cpp

   1 //===------- Linux implementation of the remap_file_pages function --------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "src/sys/mman/remap_file_pages.h"
  10
  11 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
  12 #include "src/__support/common.h"
  13 #include "src/__support/macros/config.h"
  14 #include "src/errno/libc_errno.h"
  15 #include <sys/syscall.h> // For syscall numbers.
  16
  17 namespace LIBC_NAMESPACE_DECL {
  18
  19 LLVM_LIBC_FUNCTION(int, remap_file_pages,
  20                    (void *addr, size_t size, int prot, size_t pgoff,
  21                     int flags)) {
  22 #ifdef SYS_remap_file_pages
  23   int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_remap_file_pages,
  24                                               reinterpret_cast<long>(addr),
  25                                               size, prot, pgoff, flags);
  26 #else
  27 #error "remap_file_pages syscall is not available."
  28 #endif
  29
  30   // A negative return value indicates an error with the magnitude of the
  31   // value being the error code.
  32   if (ret < 0) {
  33     libc_errno = -ret;
  34     return -1;
  35   }
  36
  37   return 0;
  38 }
  39
  40 } // namespace LIBC_NAMESPACE_DECL