Disk cache: Switch the disk cache to use the cache_thread.

Add an InFlightBackendIO class that handles posting of
cacheoperations back and forth between the IO thread and
the cachethread.

BUG=26730
TEST=unit tests


Review URL: http://codereview.chromium.org/2841034

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@51456 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 117 insertions, 40 deletions

diff --git a/net/disk_cache/entry_impl.cc b/net/disk_cache/entry_impl.cc
index 1c041d2..7f172ed 100644
--- a/net/disk_cache/entry_impl.cc
+++ b/net/disk_cache/entry_impl.cc
@@ -89,7 +89,6 @@ EntryImpl::EntryImpl(BackendImpl* backend, Addr address)
   for (int i = 0; i < kNumStreams; i++) {
     unreported_size_[i] = 0;
   }
-  key_file_ = NULL;
 }
 
 // When an entry is deleted from the cache, we clean up all the data associated
@@ -131,7 +130,7 @@ EntryImpl::~EntryImpl() {
   backend_->CacheEntryDestroyed(entry_.address());
 }
 
-void EntryImpl::Doom() {
+void EntryImpl::DoomImpl() {
   if (doomed_)
     return;
 
@@ -139,8 +138,12 @@ void EntryImpl::Doom() {
   backend_->InternalDoomEntry(this);
 }
 
+void EntryImpl::Doom() {
+  backend_->background_queue()->DoomEntryImpl(this);
+}
+
 void EntryImpl::Close() {
-  Release();
+  backend_->background_queue()->CloseEntryImpl(this);
 }
 
 std::string EntryImpl::GetKey() const {
@@ -148,26 +151,26 @@ std::string EntryImpl::GetKey() const {
   if (entry->Data()->key_len <= kMaxInternalKeyLength)
     return std::string(entry->Data()->key);
 
+  // We keep a copy of the key so that we can always return it, even if the
+  // backend is disabled.
+  if (!key_.empty())
+    return key_;
+
   Addr address(entry->Data()->long_key);
   DCHECK(address.is_initialized());
   size_t offset = 0;
   if (address.is_block_file())
     offset = address.start_block() * address.BlockSize() + kBlockHeaderSize;
 
-  if (!key_file_) {
-    // We keep a copy of the file needed to access the key so that we can
-    // always return this object's key, even if the backend is disabled.
-    COMPILE_ASSERT(kNumStreams == kKeyFileIndex, invalid_key_index);
-    key_file_ = const_cast<EntryImpl*>(this)->GetBackingFile(address,
-                                                             kKeyFileIndex);
-  }
+  COMPILE_ASSERT(kNumStreams == kKeyFileIndex, invalid_key_index);
+  File* key_file = const_cast<EntryImpl*>(this)->GetBackingFile(address,
+                                                                kKeyFileIndex);
 
-  std::string key;
-  if (!key_file_ ||
-      !key_file_->Read(WriteInto(&key, entry->Data()->key_len + 1),
-                       entry->Data()->key_len + 1, offset))
-    key.clear();
-  return key;
+  if (!key_file ||
+      !key_file->Read(WriteInto(&key_, entry->Data()->key_len + 1),
+                      entry->Data()->key_len + 1, offset))
+    key_.clear();
+  return key_;
 }
 
 Time EntryImpl::GetLastUsed() const {
@@ -188,8 +191,8 @@ int32 EntryImpl::GetDataSize(int index) const {
   return entry->Data()->data_size[index];
 }
 
-int EntryImpl::ReadData(int index, int offset, net::IOBuffer* buf, int buf_len,
-                        net::CompletionCallback* completion_callback) {
+int EntryImpl::ReadDataImpl(int index, int offset, net::IOBuffer* buf,
+                            int buf_len, CompletionCallback* callback) {
   DCHECK(node_.Data()->dirty);
   if (index < 0 || index >= kNumStreams)
     return net::ERR_INVALID_ARGUMENT;
@@ -233,8 +236,8 @@ int EntryImpl::ReadData(int index, int offset, net::IOBuffer* buf, int buf_len,
                    kBlockHeaderSize;
 
   SyncCallback* io_callback = NULL;
-  if (completion_callback)
-    io_callback = new SyncCallback(this, buf, completion_callback);
+  if (callback)
+    io_callback = new SyncCallback(this, buf, callback);
 
   bool completed;
   if (!file->Read(buf->data(), buf_len, file_offset, io_callback, &completed)) {
@@ -247,12 +250,33 @@ int EntryImpl::ReadData(int index, int offset, net::IOBuffer* buf, int buf_len,
     io_callback->Discard();
 
   ReportIOTime(kRead, start);
-  return (completed || !completion_callback) ? buf_len : net::ERR_IO_PENDING;
+  return (completed || !callback) ? buf_len : net::ERR_IO_PENDING;
 }
 
-int EntryImpl::WriteData(int index, int offset, net::IOBuffer* buf, int buf_len,
-                         net::CompletionCallback* completion_callback,
-                         bool truncate) {
+int EntryImpl::ReadData(int index, int offset, net::IOBuffer* buf, int buf_len,
+                        net::CompletionCallback* callback) {
+  if (!callback)
+    return ReadDataImpl(index, offset, buf, buf_len, callback);
+
+  DCHECK(node_.Data()->dirty);
+  if (index < 0 || index >= kNumStreams)
+    return net::ERR_INVALID_ARGUMENT;
+
+  int entry_size = entry_.Data()->data_size[index];
+  if (offset >= entry_size || offset < 0 || !buf_len)
+    return 0;
+
+  if (buf_len < 0)
+    return net::ERR_INVALID_ARGUMENT;
+
+  backend_->background_queue()->ReadData(this, index, offset, buf, buf_len,
+                                         callback);
+  return net::ERR_IO_PENDING;
+}
+
+int EntryImpl::WriteDataImpl(int index, int offset, net::IOBuffer* buf,
+                             int buf_len, CompletionCallback* callback,
+                             bool truncate) {
   DCHECK(node_.Data()->dirty);
   if (index < 0 || index >= kNumStreams)
     return net::ERR_INVALID_ARGUMENT;
@@ -262,7 +286,7 @@ int EntryImpl::WriteData(int index, int offset, net::IOBuffer* buf, int buf_len,
 
   int max_file_size = backend_->MaxFileSize();
 
-  // offset of buf_len could be negative numbers.
+  // offset or buf_len could be negative numbers.
   if (offset > max_file_size || buf_len > max_file_size ||
       offset + buf_len > max_file_size) {
     int size = offset + buf_len;
@@ -332,8 +356,8 @@ int EntryImpl::WriteData(int index, int offset, net::IOBuffer* buf, int buf_len,
     return 0;
 
   SyncCallback* io_callback = NULL;
-  if (completion_callback)
-    io_callback = new SyncCallback(this, buf, completion_callback);
+  if (callback)
+    io_callback = new SyncCallback(this, buf, callback);
 
   bool completed;
   if (!file->Write(buf->data(), buf_len, file_offset, io_callback,
@@ -347,11 +371,28 @@ int EntryImpl::WriteData(int index, int offset, net::IOBuffer* buf, int buf_len,
     io_callback->Discard();
 
   ReportIOTime(kWrite, start);
-  return (completed || !completion_callback) ? buf_len : net::ERR_IO_PENDING;
+  return (completed || !callback) ? buf_len : net::ERR_IO_PENDING;
 }
 
-int EntryImpl::ReadSparseData(int64 offset, net::IOBuffer* buf, int buf_len,
-                              net::CompletionCallback* completion_callback) {
+int EntryImpl::WriteData(int index, int offset, net::IOBuffer* buf, int buf_len,
+                         CompletionCallback* callback, bool truncate) {
+  if (!callback)
+    return WriteDataImpl(index, offset, buf, buf_len, callback, truncate);
+
+  DCHECK(node_.Data()->dirty);
+  if (index < 0 || index >= kNumStreams)
+    return net::ERR_INVALID_ARGUMENT;
+
+  if (offset < 0 || buf_len < 0)
+    return net::ERR_INVALID_ARGUMENT;
+
+  backend_->background_queue()->WriteData(this, index, offset, buf, buf_len,
+                                          truncate, callback);
+  return net::ERR_IO_PENDING;
+}
+
+int EntryImpl::ReadSparseDataImpl(int64 offset, net::IOBuffer* buf, int buf_len,
+                                  CompletionCallback* callback) {
   DCHECK(node_.Data()->dirty);
   int result = InitSparseData();
   if (net::OK != result)
@@ -359,13 +400,23 @@ int EntryImpl::ReadSparseData(int64 offset, net::IOBuffer* buf, int buf_len,
 
   TimeTicks start = TimeTicks::Now();
   result = sparse_->StartIO(SparseControl::kReadOperation, offset, buf, buf_len,
-                            completion_callback);
+                            callback);
   ReportIOTime(kSparseRead, start);
   return result;
 }
 
-int EntryImpl::WriteSparseData(int64 offset, net::IOBuffer* buf, int buf_len,
-                               net::CompletionCallback* completion_callback) {
+int EntryImpl::ReadSparseData(int64 offset, net::IOBuffer* buf, int buf_len,
+                              net::CompletionCallback* callback) {
+  if (!callback)
+    return ReadSparseDataImpl(offset, buf, buf_len, callback);
+
+  backend_->background_queue()->ReadSparseData(this, offset, buf, buf_len,
+                                               callback);
+  return net::ERR_IO_PENDING;
+}
+
+int EntryImpl::WriteSparseDataImpl(int64 offset, net::IOBuffer* buf,
+                                   int buf_len, CompletionCallback* callback) {
   DCHECK(node_.Data()->dirty);
   int result = InitSparseData();
   if (net::OK != result)
@@ -373,11 +424,25 @@ int EntryImpl::WriteSparseData(int64 offset, net::IOBuffer* buf, int buf_len,
 
   TimeTicks start = TimeTicks::Now();
   result = sparse_->StartIO(SparseControl::kWriteOperation, offset, buf,
-                            buf_len, completion_callback);
+                            buf_len, callback);
   ReportIOTime(kSparseWrite, start);
   return result;
 }
 
+int EntryImpl::WriteSparseData(int64 offset, net::IOBuffer* buf, int buf_len,
+                               net::CompletionCallback* callback) {
+  if (!callback)
+    return WriteSparseDataImpl(offset, buf, buf_len, callback);
+
+  backend_->background_queue()->WriteSparseData(this, offset, buf, buf_len,
+                                                callback);
+  return net::ERR_IO_PENDING;
+}
+
+int EntryImpl::GetAvailableRangeImpl(int64 offset, int len, int64* start) {
+  return GetAvailableRange(offset, len, start);
+}
+
 int EntryImpl::GetAvailableRange(int64 offset, int len, int64* start) {
   int result = InitSparseData();
   if (net::OK != result)
@@ -388,7 +453,9 @@ int EntryImpl::GetAvailableRange(int64 offset, int len, int64* start) {
 
 int EntryImpl::GetAvailableRange(int64 offset, int len, int64* start,
                                  CompletionCallback* callback) {
-  return GetAvailableRange(offset, len, start);
+  backend_->background_queue()->GetAvailableRange(this, offset, len, start,
+                                                  callback);
+  return net::ERR_IO_PENDING;
 }
 
 bool EntryImpl::CouldBeSparse() const {
@@ -401,17 +468,26 @@ bool EntryImpl::CouldBeSparse() const {
 }
 
 void EntryImpl::CancelSparseIO() {
+  backend_->background_queue()->CancelSparseIO(this);
+}
+
+void EntryImpl::CancelSparseIOImpl() {
   if (!sparse_.get())
     return;
 
   sparse_->CancelIO();
 }
 
-int EntryImpl::ReadyForSparseIO(net::CompletionCallback* completion_callback) {
+int EntryImpl::ReadyForSparseIOImpl(CompletionCallback* callback) {
+  return sparse_->ReadyToUse(callback);
+}
+
+int EntryImpl::ReadyForSparseIO(net::CompletionCallback* callback) {
   if (!sparse_.get())
     return net::OK;
 
-  return sparse_->ReadyToUse(completion_callback);
+  backend_->background_queue()->ReadyForSparseIO(this, callback);
+  return net::ERR_IO_PENDING;
 }
 
 // ------------------------------------------------------------------------
@@ -442,19 +518,20 @@ bool EntryImpl::CreateEntry(Addr node_address, const std::string& key,
       return false;
 
     entry_store->long_key = address.value();
-    key_file_ = GetBackingFile(address, kKeyFileIndex);
+    File* key_file = GetBackingFile(address, kKeyFileIndex);
+    key_ = key;
 
     size_t offset = 0;
     if (address.is_block_file())
       offset = address.start_block() * address.BlockSize() + kBlockHeaderSize;
 
-    if (!key_file_ || !key_file_->Write(key.data(), key.size(), offset)) {
+    if (!key_file || !key_file->Write(key.data(), key.size(), offset)) {
       DeleteData(address, kKeyFileIndex);
       return false;
     }
 
     if (address.is_separate_file())
-      key_file_->SetLength(key.size() + 1);
+      key_file->SetLength(key.size() + 1);
   } else {
     memcpy(entry_store->key, key.data(), key.size());
     entry_store->key[key.size()] = '\0';