Make command buffer commands and immediate data volatile

gpu/command_buffer/service/common_decoder.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/command_buffer/service/common_decoder.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 32 matching lines @@
 
 void CommonDecoder::Bucket::SetSize(size_t size) {
   if (size != size_) {
     data_.reset(size ? new int8_t[size] : NULL);
     size_ = size;
     memset(data_.get(), 0, size);
   }
 }
 
 bool CommonDecoder::Bucket::SetData(
-    const void* src, size_t offset, size_t size) {
+    const volatile void* src, size_t offset, size_t size) {
   if (OffsetSizeValid(offset, size)) {
-    memcpy(data_.get() + offset, src, size);
+    memcpy(data_.get() + offset, const_cast<const void*>(src), size);
     return true;
   }
   return false;
 }
 
 void CommonDecoder::Bucket::SetFromString(const char* str) {
   // Strings are passed NULL terminated to distinguish between empty string
   // and no string.
   if (!str) {
     SetSize(0);
@@ skipping 115 matching lines @@
     bucket = new Bucket();
     buckets_[bucket_id] = std::unique_ptr<Bucket>(bucket);
   }
   return bucket;
 }
 
 namespace {
 
 // Returns the address of the first byte after a struct.
 template <typename T>
-const void* AddressAfterStruct(const T& pod) {
-  return reinterpret_cast<const uint8_t*>(&pod) + sizeof(pod);
+const volatile void* AddressAfterStruct(const volatile T& pod) {
+  return reinterpret_cast<const volatile uint8_t*>(&pod) + sizeof(pod);
 }
 
 // Returns the address of the frst byte after the struct.
 template <typename RETURN_TYPE, typename COMMAND_TYPE>
-RETURN_TYPE GetImmediateDataAs(const COMMAND_TYPE& pod) {
-  return static_cast<RETURN_TYPE>(const_cast<void*>(AddressAfterStruct(pod)));
+RETURN_TYPE GetImmediateDataAs(const volatile COMMAND_TYPE& pod) {
+  return static_cast<RETURN_TYPE>(
+      const_cast<volatile void*>(AddressAfterStruct(pod)));
 }
 
 }  // anonymous namespace.
 
 // Decode command with its arguments, and call the corresponding method.
 // Note: args is a pointer to the command buffer. As such, it could be changed
 // by a (malicious) client at any time, so if validation has to happen, it
 // should operate on a copy of them.
-error::Error CommonDecoder::DoCommonCommand(
-    unsigned int command,
-    unsigned int arg_count,
-    const void* cmd_data) {
+error::Error CommonDecoder::DoCommonCommand(unsigned int command,
+                                            unsigned int arg_count,
+                                            const volatile void* cmd_data) {
   if (command < arraysize(command_info)) {
     const CommandInfo& info = command_info[command];
     unsigned int info_arg_count = static_cast<unsigned int>(info.arg_count);
     if ((info.arg_flags == cmd::kFixed && arg_count == info_arg_count) ||
         (info.arg_flags == cmd::kAtLeastN && arg_count >= info_arg_count)) {
       uint32_t immediate_data_size =
           (arg_count - info_arg_count) * sizeof(CommandBufferEntry);  // NOLINT
       return (this->*info.cmd_handler)(immediate_data_size, cmd_data);
     } else {
       return error::kInvalidArguments;
     }
   }
   return error::kUnknownCommand;
 }
 
 error::Error CommonDecoder::HandleNoop(uint32_t immediate_data_size,
-                                       const void* cmd_data) {
+                                       const volatile void* cmd_data) {
   return error::kNoError;
 }
 
 error::Error CommonDecoder::HandleSetToken(uint32_t immediate_data_size,
-                                           const void* cmd_data) {
-  const cmd::SetToken& args = *static_cast<const cmd::SetToken*>(cmd_data);
+                                           const volatile void* cmd_data) {
+  const volatile cmd::SetToken& args =
+      *static_cast<const volatile cmd::SetToken*>(cmd_data);
   engine_->set_token(args.token);
   return error::kNoError;
 }
 
 error::Error CommonDecoder::HandleSetBucketSize(uint32_t immediate_data_size,
-                                                const void* cmd_data) {
-  const cmd::SetBucketSize& args =
-      *static_cast<const cmd::SetBucketSize*>(cmd_data);
+                                                const volatile void* cmd_data) {
+  const volatile cmd::SetBucketSize& args =
+      *static_cast<const volatile cmd::SetBucketSize*>(cmd_data);
   uint32_t bucket_id = args.bucket_id;
   uint32_t size = args.size;
   if (size > max_bucket_size_)
     return error::kOutOfBounds;
 
   Bucket* bucket = CreateBucket(bucket_id);
   bucket->SetSize(size);
   return error::kNoError;
 }
 
 error::Error CommonDecoder::HandleSetBucketData(uint32_t immediate_data_size,
-                                                const void* cmd_data) {
-  const cmd::SetBucketData& args =
-      *static_cast<const cmd::SetBucketData*>(cmd_data);
+                                                const volatile void* cmd_data) {
+  const volatile cmd::SetBucketData& args =
+      *static_cast<const volatile cmd::SetBucketData*>(cmd_data);
   uint32_t bucket_id = args.bucket_id;
   uint32_t offset = args.offset;
   uint32_t size = args.size;
   const void* data = GetSharedMemoryAs<const void*>(
       args.shared_memory_id, args.shared_memory_offset, size);
   if (!data) {
     return error::kInvalidArguments;
   }
   Bucket* bucket = GetBucket(bucket_id);
   if (!bucket) {
     return error::kInvalidArguments;
   }
   if (!bucket->SetData(data, offset, size)) {
     return error::kInvalidArguments;
   }
 
   return error::kNoError;
 }
 
 error::Error CommonDecoder::HandleSetBucketDataImmediate(
     uint32_t immediate_data_size,
-    const void* cmd_data) {
-  const cmd::SetBucketDataImmediate& args =
-      *static_cast<const cmd::SetBucketDataImmediate*>(cmd_data);
-  const void* data = GetImmediateDataAs<const void*>(args);
+    const volatile void* cmd_data) {
+  const volatile cmd::SetBucketDataImmediate& args =
+      *static_cast<const volatile cmd::SetBucketDataImmediate*>(cmd_data);
+  const volatile void* data = GetImmediateDataAs<const volatile void*>(args);
   uint32_t bucket_id = args.bucket_id;
   uint32_t offset = args.offset;
   uint32_t size = args.size;
   if (size > immediate_data_size) {
     return error::kInvalidArguments;
   }
   Bucket* bucket = GetBucket(bucket_id);
   if (!bucket) {
     return error::kInvalidArguments;
   }
   if (!bucket->SetData(data, offset, size)) {
     return error::kInvalidArguments;
   }
   return error::kNoError;
 }
 
-error::Error CommonDecoder::HandleGetBucketStart(uint32_t immediate_data_size,
-                                                 const void* cmd_data) {
-  const cmd::GetBucketStart& args =
-      *static_cast<const cmd::GetBucketStart*>(cmd_data);
+error::Error CommonDecoder::HandleGetBucketStart(
+    uint32_t immediate_data_size,
+    const volatile void* cmd_data) {
+  const volatile cmd::GetBucketStart& args =
+      *static_cast<const volatile cmd::GetBucketStart*>(cmd_data);
   uint32_t bucket_id = args.bucket_id;
   uint32_t* result = GetSharedMemoryAs<uint32_t*>(
       args.result_memory_id, args.result_memory_offset, sizeof(*result));
   int32_t data_memory_id = args.data_memory_id;
   uint32_t data_memory_offset = args.data_memory_offset;
   uint32_t data_memory_size = args.data_memory_size;
   uint8_t* data = NULL;
   if (data_memory_size != 0 || data_memory_id != 0 || data_memory_offset != 0) {
     data = GetSharedMemoryAs<uint8_t*>(data_memory_id, data_memory_offset,
                                        data_memory_size);
@@ skipping 15 matching lines @@
   uint32_t bucket_size = bucket->size();
   *result = bucket_size;
   if (data) {
     uint32_t size = std::min(data_memory_size, bucket_size);
     memcpy(data, bucket->GetData(0, size), size);
   }
   return error::kNoError;
 }
 
 error::Error CommonDecoder::HandleGetBucketData(uint32_t immediate_data_size,
-                                                const void* cmd_data) {
-  const cmd::GetBucketData& args =
-      *static_cast<const cmd::GetBucketData*>(cmd_data);
+                                                const volatile void* cmd_data) {
+  const volatile cmd::GetBucketData& args =
+      *static_cast<const volatile cmd::GetBucketData*>(cmd_data);
   uint32_t bucket_id = args.bucket_id;
   uint32_t offset = args.offset;
   uint32_t size = args.size;
   void* data = GetSharedMemoryAs<void*>(
       args.shared_memory_id, args.shared_memory_offset, size);
   if (!data) {
     return error::kInvalidArguments;
   }
   Bucket* bucket = GetBucket(bucket_id);
   if (!bucket) {
     return error::kInvalidArguments;
   }
   const void* src = bucket->GetData(offset, size);
   if (!src) {
       return error::kInvalidArguments;
   }
   memcpy(data, src, size);
   return error::kNoError;
 }
 
 }  // namespace gpu