blob: 0bb336d45a153e66a70ed3ee85d9eb1328cad02f [file] [log] [blame]
/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ART_LIBARTBASE_BASE_MEMFD_H_
#define ART_LIBARTBASE_BASE_MEMFD_H_
#include <fcntl.h>
#include <unistd.h>
#if defined(__BIONIC__)
#include <linux/memfd.h> // To access memfd flags.
#else
// If memfd flags don't exist in the current toolchain, define them ourselves.
#ifndef F_ADD_SEALS
# define F_ADD_SEALS (1033)
#endif
#ifndef F_GET_SEALS
# define F_GET_SEALS (1034)
#endif
#ifndef F_SEAL_SEAL
# define F_SEAL_SEAL 0x0001
#endif
#ifndef F_SEAL_SHRINK
# define F_SEAL_SHRINK 0x0002
#endif
#ifndef F_SEAL_GROW
# define F_SEAL_GROW 0x0004
#endif
#ifndef F_SEAL_WRITE
# define F_SEAL_WRITE 0x0008
#endif
#ifndef F_SEAL_FUTURE_WRITE
# define F_SEAL_FUTURE_WRITE 0x0010
#endif
#ifndef MFD_ALLOW_SEALING
# define MFD_ALLOW_SEALING 0x0002U
#endif
#endif
namespace art {
// Call memfd(2) if available on platform and return result. This call also makes a kernel version
// check for safety on older kernels (b/116769556)..
int memfd_create(const char* name, unsigned int flags);
// Call memfd(2) if available on platform and return result. Try to give us an unlinked FD in some
// other way if memfd fails or isn't supported.
int memfd_create_compat(const char* name, unsigned int flags);
// Return whether the kernel supports sealing future writes of a memfd.
bool IsSealFutureWriteSupported();
} // namespace art
#endif // ART_LIBARTBASE_BASE_MEMFD_H_