/*
* 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.
*/
#include <limits.h>
#include <errno.h>
#include <pthread.h>
#include <unistd.h>
#include <string.h>
#include <stdarg.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <cutils/log.h>
#include <cutils/atomic.h>
#include <hardware/hardware.h>
#include <hardware/gralloc.h>
#include <linux/android_pmem.h>
#include "gralloc_priv.h"
// we need this for now because pmem cannot mmap at an offset
#define PMEM_HACK 1
/* desktop Linux needs a little help with gettid() */
#if defined(ARCH_X86) && !defined(HAVE_ANDROID_OS)
#define __KERNEL__
# include <linux/unistd.h>
pid_t gettid() { return syscall(__NR_gettid);}
#undef __KERNEL__
#endif
/*****************************************************************************/
static int gralloc_map(gralloc_module_t const* module,
buffer_handle_t handle,
void** vaddr)
{
private_handle_t* hnd = (private_handle_t*)handle;
if (!(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) {
size_t size = hnd->size;
#if PMEM_HACK
size += hnd->offset;
#endif
void* mappedAddress = mmap(0, size,
PROT_READ|PROT_WRITE, MAP_SHARED, hnd->fd, 0);
if (mappedAddress == MAP_FAILED) {
LOGE("Could not mmap handle %p, fd=%d (%s)",
handle, hnd->fd, strerror(errno));
hnd->base = 0;
return -errno;
}
hnd->base = intptr_t(mappedAddress) + hnd->offset;
//LOGD("gralloc_map() succeeded fd=%d, off=%d, size=%d, vaddr=%p",
// hnd->fd, hnd->offset, hnd->size, mappedAddress);
}
*vaddr = (void*)hnd->base;
return 0;
}
static int gralloc_unmap(gralloc_module_t const* module,
buffer_handle_t handle)
{
private_handle_t* hnd = (private_handle_t*)handle;
if (!(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) {
void* base = (void*)hnd->base;
size_t size = hnd->size;
#if PMEM_HACK
base = (void*)(intptr_t(base) - hnd->offset);
size += hnd->offset;
#endif
//LOGD("unmapping from %p, size=%d", base, size);
if (munmap(base, size) < 0) {
LOGE("Could not unmap %s", strerror(errno));
}
}
hnd->base = 0;
return 0;
}
/*****************************************************************************/
static pthread_mutex_t sMapLock = PTHREAD_MUTEX_INITIALIZER;
/*****************************************************************************/
int gralloc_register_buffer(gralloc_module_t const* module,
buffer_handle_t handle)
{
if (private_handle_t::validate(handle) < 0)
return -EINVAL;
// In this implementation, we don't need to do anything here
/* NOTE: we need to initialize the buffer as not mapped/not locked
* because it shouldn't when this function is called the first time
* in a new process. Ideally these flags shouldn't be part of the
* handle, but instead maintained in the kernel or at least
* out-of-line
*/
// if this handle was created in this process, then we keep it as is.
private_handle_t* hnd = (private_handle_t*)handle;
if (hnd->pid != getpid()) {
hnd->base = 0;
hnd->lockState = 0;
hnd->writeOwner = 0;
}
return 0;
}
int gralloc_unregister_buffer(gralloc_module_t const* module,
buffer_handle_t handle)
{
if (private_handle_t::validate(handle) < 0)
return -EINVAL;
/*
* If the buffer has been mapped during a lock operation, it's time
* to un-map it. It's an error to be here with a locked buffer.
* NOTE: the framebuffer is handled differently and is never unmapped.
*/
private_handle_t* hnd = (private_handle_t*)handle;
LOGE_IF(hnd->lockState & private_handle_t::LOCK_STATE_READ_MASK,
"[unregister] handle %p still locked (state=%08x)",
hnd, hnd->lockState);
// never unmap buffers that were created in this process
if (hnd->pid != getpid()) {
if (hnd->lockState & private_handle_t::LOCK_STATE_MAPPED) {
gralloc_unmap(module, handle);
}
hnd->base = 0;
hnd->lockState = 0;
hnd->writeOwner = 0;
}
return 0;
}
int terminateBuffer(gralloc_module_t const* module,
private_handle_t* hnd)
{
/*
* If the buffer has been mapped during a lock operation, it's time
* to un-map it. It's an error to be here with a locked buffer.
*/
LOGE_IF(hnd->lockState & private_handle_t::LOCK_STATE_READ_MASK,
"[terminate] handle %p still locked (state=%08x)",
hnd, hnd->lockState);
if (hnd->lockState & private_handle_t::LOCK_STATE_MAPPED) {
// this buffer was mapped, unmap it now
if ((hnd->flags & private_handle_t::PRIV_FLAGS_USES_PMEM) ||
(hnd->flags & private_handle_t::PRIV_FLAGS_USES_PMEM_ADSP)) {
if (hnd->pid != getpid()) {
// ... unless it's a "master" pmem buffer, that is a buffer
// mapped in the process it's been allocated.
// (see gralloc_alloc_buffer())
gralloc_unmap(module, hnd);
}
} else {
gralloc_unmap(module, hnd);
}
}
return 0;
}
int gralloc_lock(gralloc_module_t const* module,
buffer_handle_t handle, int usage,
int l, int t, int w, int h,
void** vaddr)
{
if (private_handle_t::validate(handle) < 0)
return -EINVAL;
int err = 0;
private_handle_t* hnd = (private_handle_t*)handle;
int32_t current_value, new_value;
int retry;
do {
current_value = hnd->lockState;
new_value = current_value;
if (current_value & private_handle_t::LOCK_STATE_WRITE) {
// already locked for write
LOGE("handle %p already locked for write", handle);
return -EBUSY;
} else if (current_value & private_handle_t::LOCK_STATE_READ_MASK) {
// already locked for read
if (usage & (GRALLOC_USAGE_SW_WRITE_MASK | GRALLOC_USAGE_HW_RENDER)) {
LOGE("handle %p already locked for read", handle);
return -EBUSY;
} else {
// this is not an error
//LOGD("%p already locked for read... count = %d",
// handle, (current_value & ~(1<<31)));
}
}
// not currently locked
if (usage & (GRALLOC_USAGE_SW_WRITE_MASK | GRALLOC_USAGE_HW_RENDER)) {
// locking for write
new_value |= private_handle_t::LOCK_STATE_WRITE;
}
new_value++;
retry = android_atomic_cmpxchg(current_value, new_value,
(volatile int32_t*)&hnd->lockState);
} while (retry);
if (new_value & private_handle_t::LOCK_STATE_WRITE) {
// locking for write, store the tid
hnd->writeOwner = gettid();
}
// if requesting sw write for non-framebuffer handles, flag for
// flushing at unlock
const uint32_t pmemMask =
private_handle_t::PRIV_FLAGS_USES_PMEM |
private_handle_t::PRIV_FLAGS_USES_PMEM_ADSP;
if ((usage & GRALLOC_USAGE_SW_WRITE_MASK) &&
(hnd->flags & pmemMask) &&
!(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) {
hnd->flags |= private_handle_t::PRIV_FLAGS_NEEDS_FLUSH;
}
if (usage & (GRALLOC_USAGE_SW_READ_MASK | GRALLOC_USAGE_SW_WRITE_MASK)) {
if (!(current_value & private_handle_t::LOCK_STATE_MAPPED)) {
// we need to map for real
pthread_mutex_t* const lock = &sMapLock;
pthread_mutex_lock(lock);
if (!(hnd->lockState & private_handle_t::LOCK_STATE_MAPPED)) {
err = gralloc_map(module, handle, vaddr);
if (err == 0) {
android_atomic_or(private_handle_t::LOCK_STATE_MAPPED,
(volatile int32_t*)&(hnd->lockState));
}
}
pthread_mutex_unlock(lock);
}
*vaddr = (void*)hnd->base;
}
return err;
}
int gralloc_unlock(gralloc_module_t const* module,
buffer_handle_t handle)
{
if (private_handle_t::validate(handle) < 0)
return -EINVAL;
private_handle_t* hnd = (private_handle_t*)handle;
int32_t current_value, new_value;
if (hnd->flags & private_handle_t::PRIV_FLAGS_NEEDS_FLUSH) {
struct pmem_region region;
int err;
region.offset = hnd->offset;
region.len = hnd->size;
err = ioctl(hnd->fd, PMEM_CACHE_FLUSH, ®ion);
LOGE_IF(err < 0, "cannot flush handle %p (offs=%x len=%x)\n",
hnd, hnd->offset, hnd->size);
hnd->flags &= ~private_handle_t::PRIV_FLAGS_NEEDS_FLUSH;
}
do {
current_value = hnd->lockState;
new_value = current_value;
if (current_value & private_handle_t::LOCK_STATE_WRITE) {
// locked for write
if (hnd->writeOwner == gettid()) {
hnd->writeOwner = 0;
new_value &= ~private_handle_t::LOCK_STATE_WRITE;
}
}
if ((new_value & private_handle_t::LOCK_STATE_READ_MASK) == 0) {
LOGE("handle %p not locked", handle);
return -EINVAL;
}
new_value--;
} while (android_atomic_cmpxchg(current_value, new_value,
(volatile int32_t*)&hnd->lockState));
return 0;
}
/*****************************************************************************/
int gralloc_perform(struct gralloc_module_t const* module,
int operation, ... )
{
int res = -EINVAL;
va_list args;
va_start(args, operation);
switch (operation) {
case GRALLOC_MODULE_PERFORM_CREATE_HANDLE_FROM_BUFFER: {
int fd = va_arg(args, int);
size_t size = va_arg(args, size_t);
size_t offset = va_arg(args, size_t);
void* base = va_arg(args, void*);
// validate that it's indeed a pmem buffer
pmem_region region;
if (ioctl(fd, PMEM_GET_SIZE, ®ion) < 0) {
break;
}
native_handle_t** handle = va_arg(args, native_handle_t**);
private_handle_t* hnd = (private_handle_t*)native_handle_create(
private_handle_t::sNumFds, private_handle_t::sNumInts);
hnd->magic = private_handle_t::sMagic;
hnd->fd = fd;
hnd->flags = private_handle_t::PRIV_FLAGS_USES_PMEM;
hnd->size = size;
hnd->offset = offset;
hnd->base = intptr_t(base) + offset;
hnd->lockState = private_handle_t::LOCK_STATE_MAPPED;
*handle = (native_handle_t *)hnd;
res = 0;
break;
}
}
va_end(args);
return res;
}