1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "berberis/base/exec_region_anonymous.h"
18 
19 #include <sys/mman.h>
20 
21 #include "berberis/base/fd.h"
22 #include "berberis/base/mmap.h"
23 
24 namespace berberis {
25 
Create(size_t size)26 ExecRegion ExecRegionAnonymousFactory::Create(size_t size) {
27   size = AlignUpPageSize(size);
28 
29   auto fd = CreateMemfdOrDie("exec");
30   FtruncateOrDie(fd, static_cast<off64_t>(size));
31 
32   ExecRegion result{
33       static_cast<uint8_t*>(MmapImplOrDie(
34           {.size = size, .prot = PROT_READ | PROT_EXEC, .flags = MAP_SHARED, .fd = fd})),
35       static_cast<uint8_t*>(MmapImplOrDie(
36           {.size = size, .prot = PROT_READ | PROT_WRITE, .flags = MAP_SHARED, .fd = fd})),
37       size};
38 
39   CloseUnsafe(fd);
40   return result;
41 }
42 
43 }  // namespace berberis
44