platform_system_core/libpixelflinger/codeflinger/CodeCache.h
Nick Kralevich beeeee705b Allow pixelflinger to work when NX (No Execute) is enabled.
Instead of allocating memory from the (non executable) heap,
allocate memory using mspace and ensure that we use mprotect
to mark it as PROT_EXEC.  This allows pixelflinger to
continue to work even when NX protections are enabled.

Testing: Using the ApiDemos market app, verify that
Apidemos -> Graphics -> OpenGL ES -> GLSurfaceView
works when "adb shell setprop debug.egl.hw 0" is set.

Change-Id: Ib569cd2543c6fa25688ee76325a712bc2347450b
2010-05-07 16:35:52 -07:00

137 lines
3.9 KiB
C++

/* libs/pixelflinger/codeflinger/CodeCache.h
**
** Copyright 2006, 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 ANDROID_CODECACHE_H
#define ANDROID_CODECACHE_H
#include <stdint.h>
#include <pthread.h>
#include <sys/types.h>
#include <cutils/mspace.h>
#include "tinyutils/KeyedVector.h"
#include "tinyutils/smartpointer.h"
namespace android {
// ----------------------------------------------------------------------------
class AssemblyKeyBase {
public:
virtual ~AssemblyKeyBase() { }
virtual int compare_type(const AssemblyKeyBase& key) const = 0;
};
template <typename T>
class AssemblyKey : public AssemblyKeyBase
{
public:
AssemblyKey(const T& rhs) : mKey(rhs) { }
virtual int compare_type(const AssemblyKeyBase& key) const {
const T& rhs = static_cast<const AssemblyKey&>(key).mKey;
return android::compare_type(mKey, rhs);
}
private:
T mKey;
};
// ----------------------------------------------------------------------------
class Assembly
{
public:
Assembly(size_t size);
virtual ~Assembly();
ssize_t size() const;
uint32_t* base() const;
ssize_t resize(size_t size);
// protocol for sp<>
void incStrong(const void* id) const;
void decStrong(const void* id) const;
typedef void weakref_type;
private:
static mspace getMspace();
void ensureMbaseExecutable();
mutable int32_t mCount;
uint32_t* mBase;
size_t mSize;
};
// ----------------------------------------------------------------------------
class CodeCache
{
public:
// pretty simple cache API...
CodeCache(size_t size);
~CodeCache();
sp<Assembly> lookup(const AssemblyKeyBase& key) const;
int cache( const AssemblyKeyBase& key,
const sp<Assembly>& assembly);
private:
// nothing to see here...
struct cache_entry_t {
inline cache_entry_t() { }
inline cache_entry_t(const sp<Assembly>& a, int64_t w)
: entry(a), when(w) { }
sp<Assembly> entry;
mutable int64_t when;
};
class key_t {
friend int compare_type(
const key_value_pair_t<key_t, cache_entry_t>&,
const key_value_pair_t<key_t, cache_entry_t>&);
const AssemblyKeyBase* mKey;
public:
key_t() { };
key_t(const AssemblyKeyBase& k) : mKey(&k) { }
};
mutable pthread_mutex_t mLock;
mutable int64_t mWhen;
size_t mCacheSize;
size_t mCacheInUse;
KeyedVector<key_t, cache_entry_t> mCacheData;
friend int compare_type(
const key_value_pair_t<key_t, cache_entry_t>&,
const key_value_pair_t<key_t, cache_entry_t>&);
};
// KeyedVector uses compare_type(), which is more efficient, than
// just using operator < ()
inline int compare_type(
const key_value_pair_t<CodeCache::key_t, CodeCache::cache_entry_t>& lhs,
const key_value_pair_t<CodeCache::key_t, CodeCache::cache_entry_t>& rhs)
{
return lhs.key.mKey->compare_type(*(rhs.key.mKey));
}
// ----------------------------------------------------------------------------
}; // namespace android
#endif //ANDROID_CODECACHE_H