libs/surfaceflinger/GPUHardware/GPUHardware.cpp - android_frameworks_native - Gitiles

 /*
  * Copyright (C) 2008 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.
  */

 #define LOG_TAG "SurfaceFlinger"

 #include <stdlib.h>
 #include <stdio.h>
 #include <stdint.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
 #include <math.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/ioctl.h>

 #include <cutils/log.h>
 #include <cutils/properties.h>

 #include <binder/IBinder.h>
 #include <binder/MemoryDealer.h>
 #include <binder/MemoryBase.h>
 #include <binder/MemoryHeapPmem.h>
 #include <binder/MemoryHeapBase.h>
 #include <binder/IPCThreadState.h>
 #include <utils/StopWatch.h>

 #include <ui/ISurfaceComposer.h>

 #include "VRamHeap.h"
 #include "GPUHardware.h"

 #if HAVE_ANDROID_OS
 #include <linux/android_pmem.h>
 #endif

 #include "GPUHardware/GPUHardware.h"


 /*
  * Manage the GPU. This implementation is very specific to the G1.
  * There are no abstraction here.
  *
  * All this code will soon go-away and be replaced by a new architecture
  * for managing graphics accelerators.
  *
  * In the meantime, it is conceptually possible to instantiate a
  * GPUHardwareInterface for another GPU (see GPUFactory at the bottom
  * of this file); practically... doubtful.
  *
  */

 namespace android {

 // ---------------------------------------------------------------------------

 class GPUClientHeap;
 class GPUAreaHeap;

 class GPUHardware : public GPUHardwareInterface, public IBinder::DeathRecipient
 {
 public:
     static const int GPU_RESERVED_SIZE;
     static const int GPUR_SIZE;

             GPUHardware();
     virtual ~GPUHardware();

     virtual void revoke(int pid);
     virtual sp<MemoryDealer> request(int pid);
     virtual status_t request(int pid,
             const sp<IGPUCallback>& callback,
             ISurfaceComposer::gpu_info_t* gpu);

     virtual status_t friendlyRevoke();
     virtual void unconditionalRevoke();

     virtual pid_t getOwner() const { return mOwner; }

     // used for debugging only...
     virtual sp<SimpleBestFitAllocator> getAllocator() const;

 private:


     enum {
         NO_OWNER = -1,
     };

     struct GPUArea {
         sp<GPUAreaHeap>     heap;
         sp<MemoryHeapPmem>  clientHeap;
         sp<IMemory> map();
     };

     struct Client {
         pid_t       pid;
         GPUArea     smi;
         GPUArea     ebi;
         GPUArea     reg;
         void createClientHeaps();
         void revokeAllHeaps();
     };

     Client& getClientLocked(pid_t pid);
     status_t requestLocked(int pid);
     void releaseLocked();
     void takeBackGPULocked();
     void registerCallbackLocked(const sp<IGPUCallback>& callback,
             Client& client);

     virtual void binderDied(const wp<IBinder>& who);

     mutable Mutex           mLock;
     sp<GPUAreaHeap>         mSMIHeap;
     sp<GPUAreaHeap>         mEBIHeap;
     sp<GPUAreaHeap>         mREGHeap;

     KeyedVector<pid_t, Client> mClients;
     DefaultKeyedVector< wp<IBinder>, pid_t > mRegisteredClients;

     pid_t                   mOwner;

     sp<MemoryDealer>        mCurrentAllocator;
     sp<IGPUCallback>        mCallback;

     sp<SimpleBestFitAllocator>  mAllocator;

     Condition               mCondition;
 };

 // size reserved for GPU surfaces
 // 1200 KB fits exactly:
 //  - two 320*480 16-bits double-buffered surfaces
 //  - one 320*480 32-bits double-buffered surface
 //  - one 320*240 16-bits double-buffered, 4x anti-aliased surface
 const int GPUHardware::GPU_RESERVED_SIZE  = 1200 * 1024;
 const int GPUHardware::GPUR_SIZE          = 1 * 1024 * 1024;

 // ---------------------------------------------------------------------------

 /*
  * GPUHandle is a special IMemory given to the client. It represents their
  * handle to the GPU. Once they give it up, they loose GPU access, or if
  * they explicitly revoke their access through the binder code 1000.
  * In both cases, this triggers a callback to revoke()
  * first, and then actually powers down the chip.
  *
  * In the case of a misbehaving app, GPUHardware can ask for an immediate
  * release of the GPU to the target process which should answer by calling
  * code 1000 on GPUHandle. If it doesn't in a timely manner, the GPU will
  * be revoked from under their feet.
  *
  * We should never hold a strong reference on GPUHandle. In practice this
  * shouldn't be a big issue though because clients should use code 1000 and
  * not rely on the dtor being called.
  *
  */

 class GPUClientHeap : public MemoryHeapPmem
 {
 public:
     GPUClientHeap(const wp<GPUHardware>& gpu,
             const sp<MemoryHeapBase>& heap)
         :  MemoryHeapPmem(heap), mGPU(gpu) { }
 protected:
     wp<GPUHardware> mGPU;
 };

 class GPUAreaHeap : public MemoryHeapBase
 {
 public:
     GPUAreaHeap(const wp<GPUHardware>& gpu,
             const char* const vram, size_t size=0, size_t reserved=0)
     : MemoryHeapBase(vram, size), mGPU(gpu) {
         if (base() != MAP_FAILED) {
             if (reserved == 0)
                 reserved = virtualSize();
             mAllocator = new SimpleBestFitAllocator(reserved);
         }
     }
     virtual sp<MemoryHeapPmem> createClientHeap() {
         sp<MemoryHeapBase> parentHeap(this);
         return new GPUClientHeap(mGPU, parentHeap);
     }
     virtual const sp<SimpleBestFitAllocator>& getAllocator() const {
         return mAllocator;
     }
 private:
     sp<SimpleBestFitAllocator>  mAllocator;
 protected:
     wp<GPUHardware> mGPU;
 };

 class GPURegisterHeap : public GPUAreaHeap
 {
 public:
     GPURegisterHeap(const sp<GPUHardware>& gpu)
         : GPUAreaHeap(gpu, "/dev/hw3d", GPUHardware::GPUR_SIZE) { }
     virtual sp<MemoryHeapPmem> createClientHeap() {
         sp<MemoryHeapBase> parentHeap(this);
         return new MemoryHeapRegs(mGPU, parentHeap);
     }
 private:
     class MemoryHeapRegs : public GPUClientHeap  {
     public:
         MemoryHeapRegs(const wp<GPUHardware>& gpu,
              const sp<MemoryHeapBase>& heap)
             : GPUClientHeap(gpu, heap) { }
         sp<MemoryHeapPmem::MemoryPmem> createMemory(size_t offset, size_t size);
         virtual void revoke();
     private:
         class GPUHandle : public MemoryHeapPmem::MemoryPmem {
         public:
             GPUHandle(const sp<GPUHardware>& gpu,
                     const sp<MemoryHeapPmem>& heap)
                 : MemoryHeapPmem::MemoryPmem(heap),
                   mGPU(gpu), mOwner(gpu->getOwner()) { }
             virtual ~GPUHandle();
             virtual sp<IMemoryHeap> getMemory(
                     ssize_t* offset, size_t* size) const;
             virtual void revoke() { };
             virtual status_t onTransact(
                     uint32_t code, const Parcel& data,
                     Parcel* reply, uint32_t flags);
         private:
             void revokeNotification();
             wp<GPUHardware> mGPU;
             pid_t mOwner;
         };
     };
 };

 GPURegisterHeap::MemoryHeapRegs::GPUHandle::~GPUHandle() {
     //LOGD("GPUHandle %p released, revoking GPU", this);
     revokeNotification();
 }
 void GPURegisterHeap::MemoryHeapRegs::GPUHandle::revokeNotification()  {
     sp<GPUHardware> hw(mGPU.promote());
     if (hw != 0) {
         hw->revoke(mOwner);
     }
 }
 sp<IMemoryHeap> GPURegisterHeap::MemoryHeapRegs::GPUHandle::getMemory(
         ssize_t* offset, size_t* size) const
 {
     sp<MemoryHeapPmem> heap = getHeap();
     if (offset) *offset = 0;
     if (size)   *size = heap !=0 ? heap->virtualSize() : 0;
     return heap;
 }
 status_t GPURegisterHeap::MemoryHeapRegs::GPUHandle::onTransact(
         uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
 {
     status_t err = BnMemory::onTransact(code, data, reply, flags);
     if (err == UNKNOWN_TRANSACTION && code == 1000) {
         int callingPid = IPCThreadState::self()->getCallingPid();
         //LOGD("pid %d voluntarily revoking gpu", callingPid);
         if (callingPid == mOwner) {
             revokeNotification();
             // we've revoked the GPU, don't do it again later when we
             // are destroyed.
             mGPU.clear();
         } else {
             LOGW("%d revoking someone else's gpu? (owner=%d)",
                     callingPid, mOwner);
         }
         err = NO_ERROR;
     }
     return err;
 }

 // ---------------------------------------------------------------------------


 sp<MemoryHeapPmem::MemoryPmem> GPURegisterHeap::MemoryHeapRegs::createMemory(
         size_t offset, size_t size)
 {
     sp<GPUHandle> memory;
     sp<GPUHardware> gpu = mGPU.promote();
     if (heapID()>0 && gpu!=0) {
 #if HAVE_ANDROID_OS
         /* this is where the GPU is powered on and the registers are mapped
          * in the client */
         //LOGD("ioctl(HW3D_GRANT_GPU)");
         int err = ioctl(heapID(), HW3D_GRANT_GPU, base());
         if (err) {
             // it can happen if the master heap has been closed already
             // in which case the GPU already is revoked (app crash for
             // instance).
             LOGW("HW3D_GRANT_GPU failed (%s), mFD=%d, base=%p",
                     strerror(errno), heapID(), base());
         }
         memory = new GPUHandle(gpu, this);
 #endif
     }
     return memory;
 }

 void GPURegisterHeap::MemoryHeapRegs::revoke()
 {
     MemoryHeapPmem::revoke();
 #if HAVE_ANDROID_OS
     if (heapID() > 0) {
         //LOGD("ioctl(HW3D_REVOKE_GPU)");
         int err = ioctl(heapID(), HW3D_REVOKE_GPU, base());
         LOGE_IF(err, "HW3D_REVOKE_GPU failed (%s), mFD=%d, base=%p",
                 strerror(errno), heapID(), base());
     }
 #endif
 }

 /*****************************************************************************/

 GPUHardware::GPUHardware()
     : mOwner(NO_OWNER)
 {
 }

 GPUHardware::~GPUHardware()
 {
 }

 status_t GPUHardware::requestLocked(int pid)
 {
     const int self_pid = getpid();
     if (pid == self_pid) {
         // can't use GPU from surfaceflinger's process
         return PERMISSION_DENIED;
     }

     if (mOwner != pid) {
         if (mREGHeap != 0) {
             if (mOwner != NO_OWNER) {
                 // someone already has the gpu.
                 takeBackGPULocked();
                 releaseLocked();
             }
         } else {
             // first time, initialize the stuff.
             if (mSMIHeap == 0)
                 mSMIHeap = new GPUAreaHeap(this, "/dev/pmem_gpu0");
             if (mEBIHeap == 0)
                 mEBIHeap = new GPUAreaHeap(this,
                         "/dev/pmem_gpu1", 0, GPU_RESERVED_SIZE);
             mREGHeap = new GPURegisterHeap(this);
             mAllocator = mEBIHeap->getAllocator();
             if (mAllocator == NULL) {
                 // something went terribly wrong.
                 mSMIHeap.clear();
                 mEBIHeap.clear();
                 mREGHeap.clear();
                 return INVALID_OPERATION;
             }
         }
         Client& client = getClientLocked(pid);
         mCurrentAllocator = new MemoryDealer(client.ebi.clientHeap, mAllocator);
         mOwner = pid;
     }
     return NO_ERROR;
 }

 sp<MemoryDealer> GPUHardware::request(int pid)
 {
     sp<MemoryDealer> dealer;
     Mutex::Autolock _l(mLock);
     Client* client;
     LOGD("pid %d requesting gpu surface (current owner = %d)", pid, mOwner);
     if (requestLocked(pid) == NO_ERROR) {
         dealer = mCurrentAllocator;
         LOGD_IF(dealer!=0, "gpu surface granted to pid %d", mOwner);
     }
     return dealer;
 }

 status_t GPUHardware::request(int pid, const sp<IGPUCallback>& callback,
         ISurfaceComposer::gpu_info_t* gpu)
 {
     if (callback == 0)
         return BAD_VALUE;

     sp<IMemory> gpuHandle;
     LOGD("pid %d requesting gpu core (owner = %d)", pid, mOwner);
     Mutex::Autolock _l(mLock);
     status_t err = requestLocked(pid);
     if (err == NO_ERROR) {
         // it's guaranteed to be there, be construction
         Client& client = mClients.editValueFor(pid);
         registerCallbackLocked(callback, client);
         gpu->count = 2;
         gpu->regions[0].region = client.smi.map();
         gpu->regions[1].region = client.ebi.map();
         gpu->regs              = client.reg.map();
         gpu->regions[0].reserved = 0;
         gpu->regions[1].reserved = GPU_RESERVED_SIZE;
         if (gpu->regs != 0) {
             //LOGD("gpu core granted to pid %d, handle base=%p",
             //        mOwner, gpu->regs->pointer());
         }
         mCallback = callback;
     } else {
         LOGW("couldn't grant gpu core to pid %d", pid);
     }
     return err;
 }

 void GPUHardware::revoke(int pid)
 {
     Mutex::Autolock _l(mLock);
     if (mOwner > 0) {
         if (pid != mOwner) {
             LOGW("GPU owned by %d, revoke from %d", mOwner, pid);
             return;
         }
         //LOGD("revoke pid=%d, owner=%d", pid, mOwner);
         // mOwner could be <0 if the same process acquired the GPU
         // several times without releasing it first.
         mCondition.signal();
         releaseLocked();
     }
 }

 status_t GPUHardware::friendlyRevoke()
 {
     Mutex::Autolock _l(mLock);
     //LOGD("friendlyRevoke owner=%d", mOwner);
     takeBackGPULocked();
     releaseLocked();
     return NO_ERROR;
 }

 void GPUHardware::takeBackGPULocked()
 {
     sp<IGPUCallback> callback = mCallback;
     mCallback.clear();
     if (callback != 0) {
         callback->gpuLost(); // one-way
         mCondition.waitRelative(mLock, ms2ns(250));
     }
 }

 void GPUHardware::releaseLocked()
 {
     //LOGD("revoking gpu from pid %d", mOwner);
     if (mOwner != NO_OWNER) {
         // this may fail because the client might have died, and have
         // been removed from the list.
         ssize_t index = mClients.indexOfKey(mOwner);
         if (index >= 0) {
             Client& client(mClients.editValueAt(index));
             client.revokeAllHeaps();
         }
         mOwner = NO_OWNER;
         mCurrentAllocator.clear();
         mCallback.clear();
     }
 }

 GPUHardware::Client& GPUHardware::getClientLocked(pid_t pid)
 {
     ssize_t index = mClients.indexOfKey(pid);
     if (index < 0) {
         Client client;
         client.pid = pid;
         client.smi.heap = mSMIHeap;
         client.ebi.heap = mEBIHeap;
         client.reg.heap = mREGHeap;
         index = mClients.add(pid, client);
     }
     Client& client(mClients.editValueAt(index));
     client.createClientHeaps();
     return client;
 }

 // ----------------------------------------------------------------------------
 // for debugging / testing ...

 sp<SimpleBestFitAllocator> GPUHardware::getAllocator() const {
     Mutex::Autolock _l(mLock);
     return mAllocator;
 }

 void GPUHardware::unconditionalRevoke()
 {
     Mutex::Autolock _l(mLock);
     releaseLocked();
 }

 // ---------------------------------------------------------------------------

 sp<IMemory> GPUHardware::GPUArea::map() {
     sp<IMemory> memory;
     if (clientHeap != 0 && heap != 0) {
         memory = clientHeap->mapMemory(0, heap->virtualSize());
     }
     return memory;
 }

 void GPUHardware::Client::createClientHeaps()
 {
     if (smi.clientHeap == 0)
         smi.clientHeap = smi.heap->createClientHeap();
     if (ebi.clientHeap == 0)
         ebi.clientHeap = ebi.heap->createClientHeap();
     if (reg.clientHeap == 0)
         reg.clientHeap = reg.heap->createClientHeap();
 }

 void GPUHardware::Client::revokeAllHeaps()
 {
     if (smi.clientHeap != 0)
         smi.clientHeap->revoke();
     if (ebi.clientHeap != 0)
         ebi.clientHeap->revoke();
     if (reg.clientHeap != 0)
         reg.clientHeap->revoke();
 }

 void GPUHardware::registerCallbackLocked(const sp<IGPUCallback>& callback,
         Client& client)
 {
     sp<IBinder> binder = callback->asBinder();
     if (mRegisteredClients.add(binder, client.pid) >= 0) {
         binder->linkToDeath(this);
     }
 }

 void GPUHardware::binderDied(const wp<IBinder>& who)
 {
     Mutex::Autolock _l(mLock);
     pid_t pid = mRegisteredClients.valueFor(who);
     if (pid != 0) {
         ssize_t index = mClients.indexOfKey(pid);
         if (index >= 0) {
             //LOGD("*** removing client at %d", index);
             Client& client(mClients.editValueAt(index));
             client.revokeAllHeaps(); // not really needed in theory
             mClients.removeItemsAt(index);
             if (mClients.size() == 0) {
                 //LOGD("*** was last client closing everything");
                 mCallback.clear();
                 mAllocator.clear();
                 mCurrentAllocator.clear();
                 mSMIHeap.clear();
                 mREGHeap.clear();

                 // NOTE: we cannot clear the EBI heap because surfaceflinger
                 // itself may be using it, since this is where surfaces
                 // are allocated. if we're in the middle of compositing
                 // a surface (even if its process just died), we cannot
                 // rip the heap under our feet.

                 mOwner = NO_OWNER;
             }
         }
     }
 }

 // ---------------------------------------------------------------------------

 sp<GPUHardwareInterface> GPUFactory::getGPU()
 {
     sp<GPUHardwareInterface> gpu;
     if (access("/dev/hw3d", F_OK) == 0) {
         gpu = new GPUHardware();
     }
     return gpu;
 }

 // ---------------------------------------------------------------------------
 }; // namespace android
	/*
	* Copyright (C) 2008 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.
	*/

	#define LOG_TAG "SurfaceFlinger"

	#include <stdlib.h>
	#include <stdio.h>
	#include <stdint.h>
	#include <unistd.h>
	#include <fcntl.h>
	#include <errno.h>
	#include <math.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <sys/ioctl.h>

	#include <cutils/log.h>
	#include <cutils/properties.h>

	#include <binder/IBinder.h>
	#include <binder/MemoryDealer.h>
	#include <binder/MemoryBase.h>
	#include <binder/MemoryHeapPmem.h>
	#include <binder/MemoryHeapBase.h>
	#include <binder/IPCThreadState.h>
	#include <utils/StopWatch.h>

	#include <ui/ISurfaceComposer.h>

	#include "VRamHeap.h"
	#include "GPUHardware.h"

	#if HAVE_ANDROID_OS
	#include <linux/android_pmem.h>
	#endif

	#include "GPUHardware/GPUHardware.h"


	/*
	* Manage the GPU. This implementation is very specific to the G1.
	* There are no abstraction here.
	*
	* All this code will soon go-away and be replaced by a new architecture
	* for managing graphics accelerators.
	*
	* In the meantime, it is conceptually possible to instantiate a
	* GPUHardwareInterface for another GPU (see GPUFactory at the bottom
	* of this file); practically... doubtful.
	*
	*/

	namespace android {

	// ---------------------------------------------------------------------------

	class GPUClientHeap;
	class GPUAreaHeap;

	class GPUHardware : public GPUHardwareInterface, public IBinder::DeathRecipient
	{
	public:
	static const int GPU_RESERVED_SIZE;
	static const int GPUR_SIZE;

	GPUHardware();
	virtual ~GPUHardware();

	virtual void revoke(int pid);
	virtual sp<MemoryDealer> request(int pid);
	virtual status_t request(int pid,
	const sp<IGPUCallback>& callback,
	ISurfaceComposer::gpu_info_t* gpu);

	virtual status_t friendlyRevoke();
	virtual void unconditionalRevoke();

	virtual pid_t getOwner() const { return mOwner; }

	// used for debugging only...
	virtual sp<SimpleBestFitAllocator> getAllocator() const;

	private:


	enum {
	NO_OWNER = -1,
	};

	struct GPUArea {
	sp<GPUAreaHeap> heap;
	sp<MemoryHeapPmem> clientHeap;
	sp<IMemory> map();
	};

	struct Client {
	pid_t pid;
	GPUArea smi;
	GPUArea ebi;
	GPUArea reg;
	void createClientHeaps();
	void revokeAllHeaps();
	};

	Client& getClientLocked(pid_t pid);
	status_t requestLocked(int pid);
	void releaseLocked();
	void takeBackGPULocked();
	void registerCallbackLocked(const sp<IGPUCallback>& callback,
	Client& client);

	virtual void binderDied(const wp<IBinder>& who);

	mutable Mutex mLock;
	sp<GPUAreaHeap> mSMIHeap;
	sp<GPUAreaHeap> mEBIHeap;
	sp<GPUAreaHeap> mREGHeap;

	KeyedVector<pid_t, Client> mClients;
	DefaultKeyedVector< wp<IBinder>, pid_t > mRegisteredClients;

	pid_t mOwner;

	sp<MemoryDealer> mCurrentAllocator;
	sp<IGPUCallback> mCallback;

	sp<SimpleBestFitAllocator> mAllocator;

	Condition mCondition;
	};

	// size reserved for GPU surfaces
	// 1200 KB fits exactly:
	// - two 320*480 16-bits double-buffered surfaces
	// - one 320*480 32-bits double-buffered surface
	// - one 320*240 16-bits double-buffered, 4x anti-aliased surface
	const int GPUHardware::GPU_RESERVED_SIZE = 1200 * 1024;
	const int GPUHardware::GPUR_SIZE = 1 * 1024 * 1024;

	// ---------------------------------------------------------------------------

	/*
	* GPUHandle is a special IMemory given to the client. It represents their
	* handle to the GPU. Once they give it up, they loose GPU access, or if
	* they explicitly revoke their access through the binder code 1000.
	* In both cases, this triggers a callback to revoke()
	* first, and then actually powers down the chip.
	*
	* In the case of a misbehaving app, GPUHardware can ask for an immediate
	* release of the GPU to the target process which should answer by calling
	* code 1000 on GPUHandle. If it doesn't in a timely manner, the GPU will
	* be revoked from under their feet.
	*
	* We should never hold a strong reference on GPUHandle. In practice this
	* shouldn't be a big issue though because clients should use code 1000 and
	* not rely on the dtor being called.
	*
	*/

	class GPUClientHeap : public MemoryHeapPmem
	{
	public:
	GPUClientHeap(const wp<GPUHardware>& gpu,
	const sp<MemoryHeapBase>& heap)
	: MemoryHeapPmem(heap), mGPU(gpu) { }
	protected:
	wp<GPUHardware> mGPU;
	};

	class GPUAreaHeap : public MemoryHeapBase
	{
	public:
	GPUAreaHeap(const wp<GPUHardware>& gpu,
	const char* const vram, size_t size=0, size_t reserved=0)
	: MemoryHeapBase(vram, size), mGPU(gpu) {
	if (base() != MAP_FAILED) {
	if (reserved == 0)
	reserved = virtualSize();
	mAllocator = new SimpleBestFitAllocator(reserved);
	}
	}
	virtual sp<MemoryHeapPmem> createClientHeap() {
	sp<MemoryHeapBase> parentHeap(this);
	return new GPUClientHeap(mGPU, parentHeap);
	}
	virtual const sp<SimpleBestFitAllocator>& getAllocator() const {
	return mAllocator;
	}
	private:
	sp<SimpleBestFitAllocator> mAllocator;
	protected:
	wp<GPUHardware> mGPU;
	};

	class GPURegisterHeap : public GPUAreaHeap
	{
	public:
	GPURegisterHeap(const sp<GPUHardware>& gpu)
	: GPUAreaHeap(gpu, "/dev/hw3d", GPUHardware::GPUR_SIZE) { }
	virtual sp<MemoryHeapPmem> createClientHeap() {
	sp<MemoryHeapBase> parentHeap(this);
	return new MemoryHeapRegs(mGPU, parentHeap);
	}
	private:
	class MemoryHeapRegs : public GPUClientHeap {
	public:
	MemoryHeapRegs(const wp<GPUHardware>& gpu,
	const sp<MemoryHeapBase>& heap)
	: GPUClientHeap(gpu, heap) { }
	sp<MemoryHeapPmem::MemoryPmem> createMemory(size_t offset, size_t size);
	virtual void revoke();
	private:
	class GPUHandle : public MemoryHeapPmem::MemoryPmem {
	public:
	GPUHandle(const sp<GPUHardware>& gpu,
	const sp<MemoryHeapPmem>& heap)
	: MemoryHeapPmem::MemoryPmem(heap),
	mGPU(gpu), mOwner(gpu->getOwner()) { }
	virtual ~GPUHandle();
	virtual sp<IMemoryHeap> getMemory(
	ssize_t* offset, size_t* size) const;
	virtual void revoke() { };
	virtual status_t onTransact(
	uint32_t code, const Parcel& data,
	Parcel* reply, uint32_t flags);
	private:
	void revokeNotification();
	wp<GPUHardware> mGPU;
	pid_t mOwner;
	};
	};
	};

	GPURegisterHeap::MemoryHeapRegs::GPUHandle::~GPUHandle() {
	//LOGD("GPUHandle %p released, revoking GPU", this);
	revokeNotification();
	}
	void GPURegisterHeap::MemoryHeapRegs::GPUHandle::revokeNotification() {
	sp<GPUHardware> hw(mGPU.promote());
	if (hw != 0) {
	hw->revoke(mOwner);
	}
	}
	sp<IMemoryHeap> GPURegisterHeap::MemoryHeapRegs::GPUHandle::getMemory(
	ssize_t* offset, size_t* size) const
	{
	sp<MemoryHeapPmem> heap = getHeap();
	if (offset) *offset = 0;
	if (size) *size = heap !=0 ? heap->virtualSize() : 0;
	return heap;
	}
	status_t GPURegisterHeap::MemoryHeapRegs::GPUHandle::onTransact(
	uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
	{
	status_t err = BnMemory::onTransact(code, data, reply, flags);
	if (err == UNKNOWN_TRANSACTION && code == 1000) {
	int callingPid = IPCThreadState::self()->getCallingPid();
	//LOGD("pid %d voluntarily revoking gpu", callingPid);
	if (callingPid == mOwner) {
	revokeNotification();
	// we've revoked the GPU, don't do it again later when we
	// are destroyed.
	mGPU.clear();
	} else {
	LOGW("%d revoking someone else's gpu? (owner=%d)",
	callingPid, mOwner);
	}
	err = NO_ERROR;
	}
	return err;
	}

	// ---------------------------------------------------------------------------


	sp<MemoryHeapPmem::MemoryPmem> GPURegisterHeap::MemoryHeapRegs::createMemory(
	size_t offset, size_t size)
	{
	sp<GPUHandle> memory;
	sp<GPUHardware> gpu = mGPU.promote();
	if (heapID()>0 && gpu!=0) {
	#if HAVE_ANDROID_OS
	/* this is where the GPU is powered on and the registers are mapped
	* in the client */
	//LOGD("ioctl(HW3D_GRANT_GPU)");
	int err = ioctl(heapID(), HW3D_GRANT_GPU, base());
	if (err) {
	// it can happen if the master heap has been closed already
	// in which case the GPU already is revoked (app crash for
	// instance).
	LOGW("HW3D_GRANT_GPU failed (%s), mFD=%d, base=%p",
	strerror(errno), heapID(), base());
	}
	memory = new GPUHandle(gpu, this);
	#endif
	}
	return memory;
	}

	void GPURegisterHeap::MemoryHeapRegs::revoke()
	{
	MemoryHeapPmem::revoke();
	#if HAVE_ANDROID_OS
	if (heapID() > 0) {
	//LOGD("ioctl(HW3D_REVOKE_GPU)");
	int err = ioctl(heapID(), HW3D_REVOKE_GPU, base());
	LOGE_IF(err, "HW3D_REVOKE_GPU failed (%s), mFD=%d, base=%p",
	strerror(errno), heapID(), base());
	}
	#endif
	}

	/*****************************************************************************/

	GPUHardware::GPUHardware()
	: mOwner(NO_OWNER)
	{
	}

	GPUHardware::~GPUHardware()
	{
	}

	status_t GPUHardware::requestLocked(int pid)
	{
	const int self_pid = getpid();
	if (pid == self_pid) {
	// can't use GPU from surfaceflinger's process
	return PERMISSION_DENIED;
	}

	if (mOwner != pid) {
	if (mREGHeap != 0) {
	if (mOwner != NO_OWNER) {
	// someone already has the gpu.
	takeBackGPULocked();
	releaseLocked();
	}
	} else {
	// first time, initialize the stuff.
	if (mSMIHeap == 0)
	mSMIHeap = new GPUAreaHeap(this, "/dev/pmem_gpu0");
	if (mEBIHeap == 0)
	mEBIHeap = new GPUAreaHeap(this,
	"/dev/pmem_gpu1", 0, GPU_RESERVED_SIZE);
	mREGHeap = new GPURegisterHeap(this);
	mAllocator = mEBIHeap->getAllocator();
	if (mAllocator == NULL) {
	// something went terribly wrong.
	mSMIHeap.clear();
	mEBIHeap.clear();
	mREGHeap.clear();
	return INVALID_OPERATION;
	}
	}
	Client& client = getClientLocked(pid);
	mCurrentAllocator = new MemoryDealer(client.ebi.clientHeap, mAllocator);
	mOwner = pid;
	}
	return NO_ERROR;
	}

	sp<MemoryDealer> GPUHardware::request(int pid)
	{
	sp<MemoryDealer> dealer;
	Mutex::Autolock _l(mLock);
	Client* client;
	LOGD("pid %d requesting gpu surface (current owner = %d)", pid, mOwner);
	if (requestLocked(pid) == NO_ERROR) {
	dealer = mCurrentAllocator;
	LOGD_IF(dealer!=0, "gpu surface granted to pid %d", mOwner);
	}
	return dealer;
	}

	status_t GPUHardware::request(int pid, const sp<IGPUCallback>& callback,
	ISurfaceComposer::gpu_info_t* gpu)
	{
	if (callback == 0)
	return BAD_VALUE;

	sp<IMemory> gpuHandle;
	LOGD("pid %d requesting gpu core (owner = %d)", pid, mOwner);
	Mutex::Autolock _l(mLock);
	status_t err = requestLocked(pid);
	if (err == NO_ERROR) {
	// it's guaranteed to be there, be construction
	Client& client = mClients.editValueFor(pid);
	registerCallbackLocked(callback, client);
	gpu->count = 2;
	gpu->regions[0].region = client.smi.map();
	gpu->regions[1].region = client.ebi.map();
	gpu->regs = client.reg.map();
	gpu->regions[0].reserved = 0;
	gpu->regions[1].reserved = GPU_RESERVED_SIZE;
	if (gpu->regs != 0) {
	//LOGD("gpu core granted to pid %d, handle base=%p",
	// mOwner, gpu->regs->pointer());
	}
	mCallback = callback;
	} else {
	LOGW("couldn't grant gpu core to pid %d", pid);
	}
	return err;
	}

	void GPUHardware::revoke(int pid)
	{
	Mutex::Autolock _l(mLock);
	if (mOwner > 0) {
	if (pid != mOwner) {
	LOGW("GPU owned by %d, revoke from %d", mOwner, pid);
	return;
	}
	//LOGD("revoke pid=%d, owner=%d", pid, mOwner);
	// mOwner could be <0 if the same process acquired the GPU
	// several times without releasing it first.
	mCondition.signal();
	releaseLocked();
	}
	}

	status_t GPUHardware::friendlyRevoke()
	{
	Mutex::Autolock _l(mLock);
	//LOGD("friendlyRevoke owner=%d", mOwner);
	takeBackGPULocked();
	releaseLocked();
	return NO_ERROR;
	}

	void GPUHardware::takeBackGPULocked()
	{
	sp<IGPUCallback> callback = mCallback;
	mCallback.clear();
	if (callback != 0) {
	callback->gpuLost(); // one-way
	mCondition.waitRelative(mLock, ms2ns(250));
	}
	}

	void GPUHardware::releaseLocked()
	{
	//LOGD("revoking gpu from pid %d", mOwner);
	if (mOwner != NO_OWNER) {
	// this may fail because the client might have died, and have
	// been removed from the list.
	ssize_t index = mClients.indexOfKey(mOwner);
	if (index >= 0) {
	Client& client(mClients.editValueAt(index));
	client.revokeAllHeaps();
	}
	mOwner = NO_OWNER;
	mCurrentAllocator.clear();
	mCallback.clear();
	}
	}

	GPUHardware::Client& GPUHardware::getClientLocked(pid_t pid)
	{
	ssize_t index = mClients.indexOfKey(pid);
	if (index < 0) {
	Client client;
	client.pid = pid;
	client.smi.heap = mSMIHeap;
	client.ebi.heap = mEBIHeap;
	client.reg.heap = mREGHeap;
	index = mClients.add(pid, client);
	}
	Client& client(mClients.editValueAt(index));
	client.createClientHeaps();
	return client;
	}

	// ----------------------------------------------------------------------------
	// for debugging / testing ...

	sp<SimpleBestFitAllocator> GPUHardware::getAllocator() const {
	Mutex::Autolock _l(mLock);
	return mAllocator;
	}

	void GPUHardware::unconditionalRevoke()
	{
	Mutex::Autolock _l(mLock);
	releaseLocked();
	}

	// ---------------------------------------------------------------------------

	sp<IMemory> GPUHardware::GPUArea::map() {
	sp<IMemory> memory;
	if (clientHeap != 0 && heap != 0) {
	memory = clientHeap->mapMemory(0, heap->virtualSize());
	}
	return memory;
	}

	void GPUHardware::Client::createClientHeaps()
	{
	if (smi.clientHeap == 0)
	smi.clientHeap = smi.heap->createClientHeap();
	if (ebi.clientHeap == 0)
	ebi.clientHeap = ebi.heap->createClientHeap();
	if (reg.clientHeap == 0)
	reg.clientHeap = reg.heap->createClientHeap();
	}

	void GPUHardware::Client::revokeAllHeaps()
	{
	if (smi.clientHeap != 0)
	smi.clientHeap->revoke();
	if (ebi.clientHeap != 0)
	ebi.clientHeap->revoke();
	if (reg.clientHeap != 0)
	reg.clientHeap->revoke();
	}

	void GPUHardware::registerCallbackLocked(const sp<IGPUCallback>& callback,
	Client& client)
	{
	sp<IBinder> binder = callback->asBinder();
	if (mRegisteredClients.add(binder, client.pid) >= 0) {
	binder->linkToDeath(this);
	}
	}

	void GPUHardware::binderDied(const wp<IBinder>& who)
	{
	Mutex::Autolock _l(mLock);
	pid_t pid = mRegisteredClients.valueFor(who);
	if (pid != 0) {
	ssize_t index = mClients.indexOfKey(pid);
	if (index >= 0) {
	//LOGD("*** removing client at %d", index);
	Client& client(mClients.editValueAt(index));
	client.revokeAllHeaps(); // not really needed in theory
	mClients.removeItemsAt(index);
	if (mClients.size() == 0) {
	//LOGD("*** was last client closing everything");
	mCallback.clear();
	mAllocator.clear();
	mCurrentAllocator.clear();
	mSMIHeap.clear();
	mREGHeap.clear();

	// NOTE: we cannot clear the EBI heap because surfaceflinger
	// itself may be using it, since this is where surfaces
	// are allocated. if we're in the middle of compositing
	// a surface (even if its process just died), we cannot
	// rip the heap under our feet.

	mOwner = NO_OWNER;
	}
	}
	}
	}

	// ---------------------------------------------------------------------------

	sp<GPUHardwareInterface> GPUFactory::getGPU()
	{
	sp<GPUHardwareInterface> gpu;
	if (access("/dev/hw3d", F_OK) == 0) {
	gpu = new GPUHardware();
	}
	return gpu;
	}

	// ---------------------------------------------------------------------------
	}; // namespace android