gralloc4: sync ion buffers around CPU usage

mali_gralloc_ion_sync is called if BOARD_USES_GRALLOC_ION_SYNC is set,
but currently the implementation is empty.  Added an implementation that
passes through to libdmabufheap's sync interface.

Test: Set camera permissions to "Ask every time"; reboot; launch camera
Test: RealCalc
Fixes: 185289225
Fixes: 186613737
Fixes: 183735780
Change-Id: I8425d2d94c0202fa2dabf8ff60d66bc8d40b6b86

1 files changed, 67 insertions, 3 deletions

diff --git a/gralloc4/src/allocator/mali_gralloc_ion.cpp b/gralloc4/src/allocator/mali_gralloc_ion.cpp
index 3b45c39..afb6620 100644
--- a/gralloc4/src/allocator/mali_gralloc_ion.cpp
+++ b/gralloc4/src/allocator/mali_gralloc_ion.cpp
@@ -127,6 +127,21 @@ struct ion_device
 	 */
 	int alloc_from_ion_heap(uint64_t usage, size_t size, unsigned int flags, int *min_pgsz);
 
+	/*
+	 *  Signals the start or end of a region where the CPU is accessing a
+	 *  buffer, allowing appropriate cache synchronization.
+	 *
+	 * @param fd        [in]    fd for the buffer
+	 * @param read      [in]    True if the CPU is reading from the buffer
+	 * @param write     [in]    True if the CPU is writing to the buffer
+	 * @param start     [in]    True if the CPU has not yet performed the
+	 *                          operations; false if the operations are
+	 *                          completed.
+	 *
+	 * @return 0 on success; an error code otherwise.
+	 */
+	int sync(int fd, bool read, bool write, bool start);
+
 private:
 	int ion_client;
 	std::unique_ptr<BufferAllocator> buffer_allocator;
@@ -390,16 +405,65 @@ int ion_device::open_and_query_ion()
 	return 0;
 }
 
+static SyncType sync_type_for_flags(const bool read, const bool write)
+{
+	if (read && !write)
+	{
+		return SyncType::kSyncRead;
+	}
+	else if (write && !read)
+	{
+		return SyncType::kSyncWrite;
+	}
+	else
+	{
+		// Deliberately also allowing "not sure" to map to ReadWrite.
+		return SyncType::kSyncReadWrite;
+	}
+}
+
+int ion_device::sync(const int fd, const bool read, const bool write, const bool start)
+{
+	if (!buffer_allocator)
+	{
+		return -1;
+	}
+
+	if (start)
+	{
+		return buffer_allocator->CpuSyncStart(fd, sync_type_for_flags(read, write));
+	}
+	else
+	{
+		return buffer_allocator->CpuSyncEnd(fd, sync_type_for_flags(read, write));
+	}
+}
+
 static int mali_gralloc_ion_sync(const private_handle_t * const hnd,
-                                       const bool /* read */,
-                                       const bool /* write */,
-                                       const bool /* start */)
+                                       const bool read,
+                                       const bool write,
+                                       const bool start)
 {
 	if (hnd == NULL)
 	{
 		return -EINVAL;
 	}
 
+	ion_device *dev = ion_device::get();
+	if (!dev)
+	{
+		return -1;
+	}
+
+	for (int i = 0; i < hnd->fd_count; i++)
+	{
+		const int fd = hnd->fds[i];
+		if (const int ret = dev->sync(fd, read, write, start))
+		{
+			return ret;
+		}
+	}
+
 	return 0;
 }