2406ce261c
Backed out changeset 8d9053f1c203 (bug 1942129) Backed out changeset 393e3c507c27 (bug 1942129) Backed out changeset 8240d353d224 (bug 1942129) Backed out changeset 8c4cd026b720 (bug 1942129) Backed out changeset 742634b0d6e9 (bug 1942129) Backed out changeset d16857f9812f (bug 1942129) Backed out changeset 7ff7af041ee7 (bug 1942129) Backed out changeset ef41d9e4c7de (bug 1942129)
131 lines
3.9 KiB
C++
131 lines
3.9 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
/* This source code was derived from Chromium code, and as such is also subject
|
|
* to the [Chromium license](ipc/chromium/src/LICENSE). */
|
|
|
|
#include "SharedMemoryPlatform.h"
|
|
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/stat.h>
|
|
#include <unistd.h>
|
|
|
|
#include "mozilla/Ashmem.h"
|
|
|
|
#ifdef MOZ_VALGRIND
|
|
# include <valgrind/valgrind.h>
|
|
#endif
|
|
|
|
#include "mozilla/Maybe.h"
|
|
#include "mozilla/UniquePtrExtensions.h"
|
|
#include "prenv.h"
|
|
|
|
namespace mozilla::ipc::shared_memory {
|
|
|
|
// Right now we do nothing different for freezable shared memory on Android.
|
|
static Maybe<PlatformHandle> CreateImpl(size_t aSize, bool aFreezable) {
|
|
MOZ_ASSERT(aSize > 0);
|
|
|
|
int fd = mozilla::android::ashmem_create(nullptr, aSize);
|
|
if (fd < 0) {
|
|
MOZ_LOG_FMT(gSharedMemoryLog, LogLevel::Warning, "failed to open shm: {}",
|
|
strerror(errno));
|
|
return Nothing();
|
|
}
|
|
|
|
return Some(fd);
|
|
}
|
|
|
|
bool Platform::Create(Handle& aHandle, size_t aSize) {
|
|
if (auto ph = CreateImpl(aSize, false)) {
|
|
aHandle.mHandle = std::move(*ph);
|
|
aHandle.mSize = aSize;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool Platform::CreateFreezable(FreezableHandle& aHandle, size_t aSize) {
|
|
if (auto ph = CreateImpl(aSize, true)) {
|
|
aHandle.mHandle = std::move(*ph);
|
|
aHandle.mSize = aSize;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
PlatformHandle Platform::CloneHandle(const PlatformHandle& aHandle) {
|
|
const int new_fd = dup(aHandle.get());
|
|
if (new_fd < 0) {
|
|
MOZ_LOG_FMT(gSharedMemoryLog, LogLevel::Warning,
|
|
"failed to duplicate file descriptor: {}", strerror(errno));
|
|
return nullptr;
|
|
}
|
|
return mozilla::UniqueFileHandle(new_fd);
|
|
}
|
|
|
|
bool Platform::Freeze(FreezableHandle& aHandle) {
|
|
if (mozilla::android::ashmem_setProt(aHandle.mHandle.get(), PROT_READ) != 0) {
|
|
MOZ_LOG_FMT(gSharedMemoryLog, LogLevel::Warning,
|
|
"failed to set ashmem read-only: {}", strerror(errno));
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
Maybe<void*> Platform::Map(const HandleBase& aHandle, uint64_t aOffset,
|
|
size_t aSize, void* aFixedAddress, bool aReadOnly) {
|
|
// Don't use MAP_FIXED when a fixed_address was specified, since that can
|
|
// replace pages that are alread mapped at that address.
|
|
void* mem =
|
|
mmap(aFixedAddress, aSize, PROT_READ | (aReadOnly ? 0 : PROT_WRITE),
|
|
MAP_SHARED, aHandle.mHandle.get(), aOffset);
|
|
|
|
if (mem == MAP_FAILED) {
|
|
MOZ_LOG_FMT(gSharedMemoryLog, LogLevel::Warning, "call to mmap failed: {}",
|
|
strerror(errno));
|
|
return Nothing();
|
|
}
|
|
|
|
if (aFixedAddress && mem != aFixedAddress) {
|
|
DebugOnly<bool> munmap_succeeded = munmap(mem, aSize) == 0;
|
|
MOZ_ASSERT(munmap_succeeded, "call to munmap failed");
|
|
return Nothing();
|
|
}
|
|
|
|
return Some(mem);
|
|
}
|
|
|
|
void Platform::Unmap(void* aMemory, size_t aSize) { munmap(aMemory, aSize); }
|
|
|
|
bool Platform::Protect(char* aAddr, size_t aSize, Access aAccess) {
|
|
int flags = PROT_NONE;
|
|
if (aAccess & AccessRead) flags |= PROT_READ;
|
|
if (aAccess & AccessWrite) flags |= PROT_WRITE;
|
|
|
|
return 0 == mprotect(aAddr, aSize, flags);
|
|
}
|
|
|
|
void* Platform::FindFreeAddressSpace(size_t aSize) {
|
|
void* memory = mmap(nullptr, aSize, PROT_NONE,
|
|
MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE, -1, 0);
|
|
if (memory == MAP_FAILED) {
|
|
return nullptr;
|
|
}
|
|
munmap(memory, aSize);
|
|
return memory;
|
|
}
|
|
|
|
size_t Platform::PageSize() { return sysconf(_SC_PAGESIZE); }
|
|
|
|
size_t Platform::AllocationGranularity() { return PageSize(); }
|
|
|
|
bool Platform::IsSafeToMap(const PlatformHandle&) { return true; }
|
|
|
|
} // namespace mozilla::ipc::shared_memory
|