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1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. | |
2 // Use of this source code is governed by a BSD-style license that can be | |
3 // found in the LICENSE file. | |
4 | |
5 #include "net/disk_cache/entry_impl.h" | |
6 | |
7 #include "base/hash.h" | |
8 #include "base/message_loop/message_loop.h" | |
9 #include "base/metrics/histogram.h" | |
10 #include "base/strings/string_util.h" | |
11 #include "net/base/io_buffer.h" | |
12 #include "net/base/net_errors.h" | |
13 #include "net/disk_cache/backend_impl.h" | |
14 #include "net/disk_cache/bitmap.h" | |
15 #include "net/disk_cache/cache_util.h" | |
16 #include "net/disk_cache/disk_format.h" | |
17 #include "net/disk_cache/net_log_parameters.h" | |
18 #include "net/disk_cache/sparse_control.h" | |
19 | |
20 #define CACHE_HISTOGRAM_MACROS_BACKEND_IMPL_OBJ backend_ | |
21 #include "net/disk_cache/histogram_macros.h" | |
22 | |
23 using base::Time; | |
24 using base::TimeDelta; | |
25 using base::TimeTicks; | |
26 | |
27 namespace { | |
28 | |
29 // Index for the file used to store the key, if any (files_[kKeyFileIndex]). | |
30 const int kKeyFileIndex = 3; | |
31 | |
32 // This class implements FileIOCallback to buffer the callback from a file IO | |
33 // operation from the actual net class. | |
34 class SyncCallback: public disk_cache::FileIOCallback { | |
35 public: | |
36 // |end_event_type| is the event type to log on completion. Logs nothing on | |
37 // discard, or when the NetLog is not set to log all events. | |
38 SyncCallback(disk_cache::EntryImpl* entry, net::IOBuffer* buffer, | |
39 const net::CompletionCallback& callback, | |
40 net::NetLog::EventType end_event_type) | |
41 : entry_(entry), callback_(callback), buf_(buffer), | |
42 start_(TimeTicks::Now()), end_event_type_(end_event_type) { | |
43 entry->AddRef(); | |
44 entry->IncrementIoCount(); | |
45 } | |
46 virtual ~SyncCallback() {} | |
47 | |
48 virtual void OnFileIOComplete(int bytes_copied) OVERRIDE; | |
49 void Discard(); | |
50 | |
51 private: | |
52 disk_cache::EntryImpl* entry_; | |
53 net::CompletionCallback callback_; | |
54 scoped_refptr<net::IOBuffer> buf_; | |
55 TimeTicks start_; | |
56 const net::NetLog::EventType end_event_type_; | |
57 | |
58 DISALLOW_COPY_AND_ASSIGN(SyncCallback); | |
59 }; | |
60 | |
61 void SyncCallback::OnFileIOComplete(int bytes_copied) { | |
62 entry_->DecrementIoCount(); | |
63 if (!callback_.is_null()) { | |
64 if (entry_->net_log().IsLoggingAllEvents()) { | |
65 entry_->net_log().EndEvent( | |
66 end_event_type_, | |
67 disk_cache::CreateNetLogReadWriteCompleteCallback(bytes_copied)); | |
68 } | |
69 entry_->ReportIOTime(disk_cache::EntryImpl::kAsyncIO, start_); | |
70 buf_ = NULL; // Release the buffer before invoking the callback. | |
71 callback_.Run(bytes_copied); | |
72 } | |
73 entry_->Release(); | |
74 delete this; | |
75 } | |
76 | |
77 void SyncCallback::Discard() { | |
78 callback_.Reset(); | |
79 buf_ = NULL; | |
80 OnFileIOComplete(0); | |
81 } | |
82 | |
83 const int kMaxBufferSize = 1024 * 1024; // 1 MB. | |
84 | |
85 } // namespace | |
86 | |
87 namespace disk_cache { | |
88 | |
89 // This class handles individual memory buffers that store data before it is | |
90 // sent to disk. The buffer can start at any offset, but if we try to write to | |
91 // anywhere in the first 16KB of the file (kMaxBlockSize), we set the offset to | |
92 // zero. The buffer grows up to a size determined by the backend, to keep the | |
93 // total memory used under control. | |
94 class EntryImpl::UserBuffer { | |
95 public: | |
96 explicit UserBuffer(BackendImpl* backend) | |
97 : backend_(backend->GetWeakPtr()), offset_(0), grow_allowed_(true) { | |
98 buffer_.reserve(kMaxBlockSize); | |
99 } | |
100 ~UserBuffer() { | |
101 if (backend_.get()) | |
102 backend_->BufferDeleted(capacity() - kMaxBlockSize); | |
103 } | |
104 | |
105 // Returns true if we can handle writing |len| bytes to |offset|. | |
106 bool PreWrite(int offset, int len); | |
107 | |
108 // Truncates the buffer to |offset| bytes. | |
109 void Truncate(int offset); | |
110 | |
111 // Writes |len| bytes from |buf| at the given |offset|. | |
112 void Write(int offset, IOBuffer* buf, int len); | |
113 | |
114 // Returns true if we can read |len| bytes from |offset|, given that the | |
115 // actual file has |eof| bytes stored. Note that the number of bytes to read | |
116 // may be modified by this method even though it returns false: that means we | |
117 // should do a smaller read from disk. | |
118 bool PreRead(int eof, int offset, int* len); | |
119 | |
120 // Read |len| bytes from |buf| at the given |offset|. | |
121 int Read(int offset, IOBuffer* buf, int len); | |
122 | |
123 // Prepare this buffer for reuse. | |
124 void Reset(); | |
125 | |
126 char* Data() { return buffer_.size() ? &buffer_[0] : NULL; } | |
127 int Size() { return static_cast<int>(buffer_.size()); } | |
128 int Start() { return offset_; } | |
129 int End() { return offset_ + Size(); } | |
130 | |
131 private: | |
132 int capacity() { return static_cast<int>(buffer_.capacity()); } | |
133 bool GrowBuffer(int required, int limit); | |
134 | |
135 base::WeakPtr<BackendImpl> backend_; | |
136 int offset_; | |
137 std::vector<char> buffer_; | |
138 bool grow_allowed_; | |
139 DISALLOW_COPY_AND_ASSIGN(UserBuffer); | |
140 }; | |
141 | |
142 bool EntryImpl::UserBuffer::PreWrite(int offset, int len) { | |
143 DCHECK_GE(offset, 0); | |
144 DCHECK_GE(len, 0); | |
145 DCHECK_GE(offset + len, 0); | |
146 | |
147 // We don't want to write before our current start. | |
148 if (offset < offset_) | |
149 return false; | |
150 | |
151 // Lets get the common case out of the way. | |
152 if (offset + len <= capacity()) | |
153 return true; | |
154 | |
155 // If we are writing to the first 16K (kMaxBlockSize), we want to keep the | |
156 // buffer offset_ at 0. | |
157 if (!Size() && offset > kMaxBlockSize) | |
158 return GrowBuffer(len, kMaxBufferSize); | |
159 | |
160 int required = offset - offset_ + len; | |
161 return GrowBuffer(required, kMaxBufferSize * 6 / 5); | |
162 } | |
163 | |
164 void EntryImpl::UserBuffer::Truncate(int offset) { | |
165 DCHECK_GE(offset, 0); | |
166 DCHECK_GE(offset, offset_); | |
167 DVLOG(3) << "Buffer truncate at " << offset << " current " << offset_; | |
168 | |
169 offset -= offset_; | |
170 if (Size() >= offset) | |
171 buffer_.resize(offset); | |
172 } | |
173 | |
174 void EntryImpl::UserBuffer::Write(int offset, IOBuffer* buf, int len) { | |
175 DCHECK_GE(offset, 0); | |
176 DCHECK_GE(len, 0); | |
177 DCHECK_GE(offset + len, 0); | |
178 DCHECK_GE(offset, offset_); | |
179 DVLOG(3) << "Buffer write at " << offset << " current " << offset_; | |
180 | |
181 if (!Size() && offset > kMaxBlockSize) | |
182 offset_ = offset; | |
183 | |
184 offset -= offset_; | |
185 | |
186 if (offset > Size()) | |
187 buffer_.resize(offset); | |
188 | |
189 if (!len) | |
190 return; | |
191 | |
192 char* buffer = buf->data(); | |
193 int valid_len = Size() - offset; | |
194 int copy_len = std::min(valid_len, len); | |
195 if (copy_len) { | |
196 memcpy(&buffer_[offset], buffer, copy_len); | |
197 len -= copy_len; | |
198 buffer += copy_len; | |
199 } | |
200 if (!len) | |
201 return; | |
202 | |
203 buffer_.insert(buffer_.end(), buffer, buffer + len); | |
204 } | |
205 | |
206 bool EntryImpl::UserBuffer::PreRead(int eof, int offset, int* len) { | |
207 DCHECK_GE(offset, 0); | |
208 DCHECK_GT(*len, 0); | |
209 | |
210 if (offset < offset_) { | |
211 // We are reading before this buffer. | |
212 if (offset >= eof) | |
213 return true; | |
214 | |
215 // If the read overlaps with the buffer, change its length so that there is | |
216 // no overlap. | |
217 *len = std::min(*len, offset_ - offset); | |
218 *len = std::min(*len, eof - offset); | |
219 | |
220 // We should read from disk. | |
221 return false; | |
222 } | |
223 | |
224 if (!Size()) | |
225 return false; | |
226 | |
227 // See if we can fulfill the first part of the operation. | |
228 return (offset - offset_ < Size()); | |
229 } | |
230 | |
231 int EntryImpl::UserBuffer::Read(int offset, IOBuffer* buf, int len) { | |
232 DCHECK_GE(offset, 0); | |
233 DCHECK_GT(len, 0); | |
234 DCHECK(Size() || offset < offset_); | |
235 | |
236 int clean_bytes = 0; | |
237 if (offset < offset_) { | |
238 // We don't have a file so lets fill the first part with 0. | |
239 clean_bytes = std::min(offset_ - offset, len); | |
240 memset(buf->data(), 0, clean_bytes); | |
241 if (len == clean_bytes) | |
242 return len; | |
243 offset = offset_; | |
244 len -= clean_bytes; | |
245 } | |
246 | |
247 int start = offset - offset_; | |
248 int available = Size() - start; | |
249 DCHECK_GE(start, 0); | |
250 DCHECK_GE(available, 0); | |
251 len = std::min(len, available); | |
252 memcpy(buf->data() + clean_bytes, &buffer_[start], len); | |
253 return len + clean_bytes; | |
254 } | |
255 | |
256 void EntryImpl::UserBuffer::Reset() { | |
257 if (!grow_allowed_) { | |
258 if (backend_.get()) | |
259 backend_->BufferDeleted(capacity() - kMaxBlockSize); | |
260 grow_allowed_ = true; | |
261 std::vector<char> tmp; | |
262 buffer_.swap(tmp); | |
263 buffer_.reserve(kMaxBlockSize); | |
264 } | |
265 offset_ = 0; | |
266 buffer_.clear(); | |
267 } | |
268 | |
269 bool EntryImpl::UserBuffer::GrowBuffer(int required, int limit) { | |
270 DCHECK_GE(required, 0); | |
271 int current_size = capacity(); | |
272 if (required <= current_size) | |
273 return true; | |
274 | |
275 if (required > limit) | |
276 return false; | |
277 | |
278 if (!backend_.get()) | |
279 return false; | |
280 | |
281 int to_add = std::max(required - current_size, kMaxBlockSize * 4); | |
282 to_add = std::max(current_size, to_add); | |
283 required = std::min(current_size + to_add, limit); | |
284 | |
285 grow_allowed_ = backend_->IsAllocAllowed(current_size, required); | |
286 if (!grow_allowed_) | |
287 return false; | |
288 | |
289 DVLOG(3) << "Buffer grow to " << required; | |
290 | |
291 buffer_.reserve(required); | |
292 return true; | |
293 } | |
294 | |
295 // ------------------------------------------------------------------------ | |
296 | |
297 EntryImpl::EntryImpl(BackendImpl* backend, Addr address, bool read_only) | |
298 : entry_(NULL, Addr(0)), node_(NULL, Addr(0)), | |
299 backend_(backend->GetWeakPtr()), doomed_(false), read_only_(read_only), | |
300 dirty_(false) { | |
301 entry_.LazyInit(backend->File(address), address); | |
302 for (int i = 0; i < kNumStreams; i++) { | |
303 unreported_size_[i] = 0; | |
304 } | |
305 } | |
306 | |
307 void EntryImpl::DoomImpl() { | |
308 if (doomed_ || !backend_.get()) | |
309 return; | |
310 | |
311 SetPointerForInvalidEntry(backend_->GetCurrentEntryId()); | |
312 backend_->InternalDoomEntry(this); | |
313 } | |
314 | |
315 int EntryImpl::ReadDataImpl(int index, int offset, IOBuffer* buf, int buf_len, | |
316 const CompletionCallback& callback) { | |
317 if (net_log_.IsLoggingAllEvents()) { | |
318 net_log_.BeginEvent( | |
319 net::NetLog::TYPE_ENTRY_READ_DATA, | |
320 CreateNetLogReadWriteDataCallback(index, offset, buf_len, false)); | |
321 } | |
322 | |
323 int result = InternalReadData(index, offset, buf, buf_len, callback); | |
324 | |
325 if (result != net::ERR_IO_PENDING && net_log_.IsLoggingAllEvents()) { | |
326 net_log_.EndEvent( | |
327 net::NetLog::TYPE_ENTRY_READ_DATA, | |
328 CreateNetLogReadWriteCompleteCallback(result)); | |
329 } | |
330 return result; | |
331 } | |
332 | |
333 int EntryImpl::WriteDataImpl(int index, int offset, IOBuffer* buf, int buf_len, | |
334 const CompletionCallback& callback, | |
335 bool truncate) { | |
336 if (net_log_.IsLoggingAllEvents()) { | |
337 net_log_.BeginEvent( | |
338 net::NetLog::TYPE_ENTRY_WRITE_DATA, | |
339 CreateNetLogReadWriteDataCallback(index, offset, buf_len, truncate)); | |
340 } | |
341 | |
342 int result = InternalWriteData(index, offset, buf, buf_len, callback, | |
343 truncate); | |
344 | |
345 if (result != net::ERR_IO_PENDING && net_log_.IsLoggingAllEvents()) { | |
346 net_log_.EndEvent( | |
347 net::NetLog::TYPE_ENTRY_WRITE_DATA, | |
348 CreateNetLogReadWriteCompleteCallback(result)); | |
349 } | |
350 return result; | |
351 } | |
352 | |
353 int EntryImpl::ReadSparseDataImpl(int64 offset, IOBuffer* buf, int buf_len, | |
354 const CompletionCallback& callback) { | |
355 DCHECK(node_.Data()->dirty || read_only_); | |
356 int result = InitSparseData(); | |
357 if (net::OK != result) | |
358 return result; | |
359 | |
360 TimeTicks start = TimeTicks::Now(); | |
361 result = sparse_->StartIO(SparseControl::kReadOperation, offset, buf, buf_len, | |
362 callback); | |
363 ReportIOTime(kSparseRead, start); | |
364 return result; | |
365 } | |
366 | |
367 int EntryImpl::WriteSparseDataImpl(int64 offset, IOBuffer* buf, int buf_len, | |
368 const CompletionCallback& callback) { | |
369 DCHECK(node_.Data()->dirty || read_only_); | |
370 int result = InitSparseData(); | |
371 if (net::OK != result) | |
372 return result; | |
373 | |
374 TimeTicks start = TimeTicks::Now(); | |
375 result = sparse_->StartIO(SparseControl::kWriteOperation, offset, buf, | |
376 buf_len, callback); | |
377 ReportIOTime(kSparseWrite, start); | |
378 return result; | |
379 } | |
380 | |
381 int EntryImpl::GetAvailableRangeImpl(int64 offset, int len, int64* start) { | |
382 int result = InitSparseData(); | |
383 if (net::OK != result) | |
384 return result; | |
385 | |
386 return sparse_->GetAvailableRange(offset, len, start); | |
387 } | |
388 | |
389 void EntryImpl::CancelSparseIOImpl() { | |
390 if (!sparse_.get()) | |
391 return; | |
392 | |
393 sparse_->CancelIO(); | |
394 } | |
395 | |
396 int EntryImpl::ReadyForSparseIOImpl(const CompletionCallback& callback) { | |
397 DCHECK(sparse_.get()); | |
398 return sparse_->ReadyToUse(callback); | |
399 } | |
400 | |
401 uint32 EntryImpl::GetHash() { | |
402 return entry_.Data()->hash; | |
403 } | |
404 | |
405 bool EntryImpl::CreateEntry(Addr node_address, const std::string& key, | |
406 uint32 hash) { | |
407 Trace("Create entry In"); | |
408 EntryStore* entry_store = entry_.Data(); | |
409 RankingsNode* node = node_.Data(); | |
410 memset(entry_store, 0, sizeof(EntryStore) * entry_.address().num_blocks()); | |
411 memset(node, 0, sizeof(RankingsNode)); | |
412 if (!node_.LazyInit(backend_->File(node_address), node_address)) | |
413 return false; | |
414 | |
415 entry_store->rankings_node = node_address.value(); | |
416 node->contents = entry_.address().value(); | |
417 | |
418 entry_store->hash = hash; | |
419 entry_store->creation_time = Time::Now().ToInternalValue(); | |
420 entry_store->key_len = static_cast<int32>(key.size()); | |
421 if (entry_store->key_len > kMaxInternalKeyLength) { | |
422 Addr address(0); | |
423 if (!CreateBlock(entry_store->key_len + 1, &address)) | |
424 return false; | |
425 | |
426 entry_store->long_key = address.value(); | |
427 File* key_file = GetBackingFile(address, kKeyFileIndex); | |
428 key_ = key; | |
429 | |
430 size_t offset = 0; | |
431 if (address.is_block_file()) | |
432 offset = address.start_block() * address.BlockSize() + kBlockHeaderSize; | |
433 | |
434 if (!key_file || !key_file->Write(key.data(), key.size(), offset)) { | |
435 DeleteData(address, kKeyFileIndex); | |
436 return false; | |
437 } | |
438 | |
439 if (address.is_separate_file()) | |
440 key_file->SetLength(key.size() + 1); | |
441 } else { | |
442 memcpy(entry_store->key, key.data(), key.size()); | |
443 entry_store->key[key.size()] = '\0'; | |
444 } | |
445 backend_->ModifyStorageSize(0, static_cast<int32>(key.size())); | |
446 CACHE_UMA(COUNTS, "KeySize", 0, static_cast<int32>(key.size())); | |
447 node->dirty = backend_->GetCurrentEntryId(); | |
448 Log("Create Entry "); | |
449 return true; | |
450 } | |
451 | |
452 bool EntryImpl::IsSameEntry(const std::string& key, uint32 hash) { | |
453 if (entry_.Data()->hash != hash || | |
454 static_cast<size_t>(entry_.Data()->key_len) != key.size()) | |
455 return false; | |
456 | |
457 return (key.compare(GetKey()) == 0); | |
458 } | |
459 | |
460 void EntryImpl::InternalDoom() { | |
461 net_log_.AddEvent(net::NetLog::TYPE_ENTRY_DOOM); | |
462 DCHECK(node_.HasData()); | |
463 if (!node_.Data()->dirty) { | |
464 node_.Data()->dirty = backend_->GetCurrentEntryId(); | |
465 node_.Store(); | |
466 } | |
467 doomed_ = true; | |
468 } | |
469 | |
470 void EntryImpl::DeleteEntryData(bool everything) { | |
471 DCHECK(doomed_ || !everything); | |
472 | |
473 if (GetEntryFlags() & PARENT_ENTRY) { | |
474 // We have some child entries that must go away. | |
475 SparseControl::DeleteChildren(this); | |
476 } | |
477 | |
478 if (GetDataSize(0)) | |
479 CACHE_UMA(COUNTS, "DeleteHeader", 0, GetDataSize(0)); | |
480 if (GetDataSize(1)) | |
481 CACHE_UMA(COUNTS, "DeleteData", 0, GetDataSize(1)); | |
482 for (int index = 0; index < kNumStreams; index++) { | |
483 Addr address(entry_.Data()->data_addr[index]); | |
484 if (address.is_initialized()) { | |
485 backend_->ModifyStorageSize(entry_.Data()->data_size[index] - | |
486 unreported_size_[index], 0); | |
487 entry_.Data()->data_addr[index] = 0; | |
488 entry_.Data()->data_size[index] = 0; | |
489 entry_.Store(); | |
490 DeleteData(address, index); | |
491 } | |
492 } | |
493 | |
494 if (!everything) | |
495 return; | |
496 | |
497 // Remove all traces of this entry. | |
498 backend_->RemoveEntry(this); | |
499 | |
500 // Note that at this point node_ and entry_ are just two blocks of data, and | |
501 // even if they reference each other, nobody should be referencing them. | |
502 | |
503 Addr address(entry_.Data()->long_key); | |
504 DeleteData(address, kKeyFileIndex); | |
505 backend_->ModifyStorageSize(entry_.Data()->key_len, 0); | |
506 | |
507 backend_->DeleteBlock(entry_.address(), true); | |
508 entry_.Discard(); | |
509 | |
510 if (!LeaveRankingsBehind()) { | |
511 backend_->DeleteBlock(node_.address(), true); | |
512 node_.Discard(); | |
513 } | |
514 } | |
515 | |
516 CacheAddr EntryImpl::GetNextAddress() { | |
517 return entry_.Data()->next; | |
518 } | |
519 | |
520 void EntryImpl::SetNextAddress(Addr address) { | |
521 DCHECK_NE(address.value(), entry_.address().value()); | |
522 entry_.Data()->next = address.value(); | |
523 bool success = entry_.Store(); | |
524 DCHECK(success); | |
525 } | |
526 | |
527 bool EntryImpl::LoadNodeAddress() { | |
528 Addr address(entry_.Data()->rankings_node); | |
529 if (!node_.LazyInit(backend_->File(address), address)) | |
530 return false; | |
531 return node_.Load(); | |
532 } | |
533 | |
534 bool EntryImpl::Update() { | |
535 DCHECK(node_.HasData()); | |
536 | |
537 if (read_only_) | |
538 return true; | |
539 | |
540 RankingsNode* rankings = node_.Data(); | |
541 if (!rankings->dirty) { | |
542 rankings->dirty = backend_->GetCurrentEntryId(); | |
543 if (!node_.Store()) | |
544 return false; | |
545 } | |
546 return true; | |
547 } | |
548 | |
549 void EntryImpl::SetDirtyFlag(int32 current_id) { | |
550 DCHECK(node_.HasData()); | |
551 if (node_.Data()->dirty && current_id != node_.Data()->dirty) | |
552 dirty_ = true; | |
553 | |
554 if (!current_id) | |
555 dirty_ = true; | |
556 } | |
557 | |
558 void EntryImpl::SetPointerForInvalidEntry(int32 new_id) { | |
559 node_.Data()->dirty = new_id; | |
560 node_.Store(); | |
561 } | |
562 | |
563 bool EntryImpl::LeaveRankingsBehind() { | |
564 return !node_.Data()->contents; | |
565 } | |
566 | |
567 // This only includes checks that relate to the first block of the entry (the | |
568 // first 256 bytes), and values that should be set from the entry creation. | |
569 // Basically, even if there is something wrong with this entry, we want to see | |
570 // if it is possible to load the rankings node and delete them together. | |
571 bool EntryImpl::SanityCheck() { | |
572 if (!entry_.VerifyHash()) | |
573 return false; | |
574 | |
575 EntryStore* stored = entry_.Data(); | |
576 if (!stored->rankings_node || stored->key_len <= 0) | |
577 return false; | |
578 | |
579 if (stored->reuse_count < 0 || stored->refetch_count < 0) | |
580 return false; | |
581 | |
582 Addr rankings_addr(stored->rankings_node); | |
583 if (!rankings_addr.SanityCheckForRankings()) | |
584 return false; | |
585 | |
586 Addr next_addr(stored->next); | |
587 if (next_addr.is_initialized() && !next_addr.SanityCheckForEntryV2()) { | |
588 STRESS_NOTREACHED(); | |
589 return false; | |
590 } | |
591 STRESS_DCHECK(next_addr.value() != entry_.address().value()); | |
592 | |
593 if (stored->state > ENTRY_DOOMED || stored->state < ENTRY_NORMAL) | |
594 return false; | |
595 | |
596 Addr key_addr(stored->long_key); | |
597 if ((stored->key_len <= kMaxInternalKeyLength && key_addr.is_initialized()) || | |
598 (stored->key_len > kMaxInternalKeyLength && !key_addr.is_initialized())) | |
599 return false; | |
600 | |
601 if (!key_addr.SanityCheckV2()) | |
602 return false; | |
603 | |
604 if (key_addr.is_initialized() && | |
605 ((stored->key_len < kMaxBlockSize && key_addr.is_separate_file()) || | |
606 (stored->key_len >= kMaxBlockSize && key_addr.is_block_file()))) | |
607 return false; | |
608 | |
609 int num_blocks = NumBlocksForEntry(stored->key_len); | |
610 if (entry_.address().num_blocks() != num_blocks) | |
611 return false; | |
612 | |
613 return true; | |
614 } | |
615 | |
616 bool EntryImpl::DataSanityCheck() { | |
617 EntryStore* stored = entry_.Data(); | |
618 Addr key_addr(stored->long_key); | |
619 | |
620 // The key must be NULL terminated. | |
621 if (!key_addr.is_initialized() && stored->key[stored->key_len]) | |
622 return false; | |
623 | |
624 if (stored->hash != base::Hash(GetKey())) | |
625 return false; | |
626 | |
627 for (int i = 0; i < kNumStreams; i++) { | |
628 Addr data_addr(stored->data_addr[i]); | |
629 int data_size = stored->data_size[i]; | |
630 if (data_size < 0) | |
631 return false; | |
632 if (!data_size && data_addr.is_initialized()) | |
633 return false; | |
634 if (!data_addr.SanityCheckV2()) | |
635 return false; | |
636 if (!data_size) | |
637 continue; | |
638 if (data_size <= kMaxBlockSize && data_addr.is_separate_file()) | |
639 return false; | |
640 if (data_size > kMaxBlockSize && data_addr.is_block_file()) | |
641 return false; | |
642 } | |
643 return true; | |
644 } | |
645 | |
646 void EntryImpl::FixForDelete() { | |
647 EntryStore* stored = entry_.Data(); | |
648 Addr key_addr(stored->long_key); | |
649 | |
650 if (!key_addr.is_initialized()) | |
651 stored->key[stored->key_len] = '\0'; | |
652 | |
653 for (int i = 0; i < kNumStreams; i++) { | |
654 Addr data_addr(stored->data_addr[i]); | |
655 int data_size = stored->data_size[i]; | |
656 if (data_addr.is_initialized()) { | |
657 if ((data_size <= kMaxBlockSize && data_addr.is_separate_file()) || | |
658 (data_size > kMaxBlockSize && data_addr.is_block_file()) || | |
659 !data_addr.SanityCheckV2()) { | |
660 STRESS_NOTREACHED(); | |
661 // The address is weird so don't attempt to delete it. | |
662 stored->data_addr[i] = 0; | |
663 // In general, trust the stored size as it should be in sync with the | |
664 // total size tracked by the backend. | |
665 } | |
666 } | |
667 if (data_size < 0) | |
668 stored->data_size[i] = 0; | |
669 } | |
670 entry_.Store(); | |
671 } | |
672 | |
673 void EntryImpl::IncrementIoCount() { | |
674 backend_->IncrementIoCount(); | |
675 } | |
676 | |
677 void EntryImpl::DecrementIoCount() { | |
678 if (backend_.get()) | |
679 backend_->DecrementIoCount(); | |
680 } | |
681 | |
682 void EntryImpl::OnEntryCreated(BackendImpl* backend) { | |
683 // Just grab a reference to the backround queue. | |
684 background_queue_ = backend->GetBackgroundQueue(); | |
685 } | |
686 | |
687 void EntryImpl::SetTimes(base::Time last_used, base::Time last_modified) { | |
688 node_.Data()->last_used = last_used.ToInternalValue(); | |
689 node_.Data()->last_modified = last_modified.ToInternalValue(); | |
690 node_.set_modified(); | |
691 } | |
692 | |
693 void EntryImpl::ReportIOTime(Operation op, const base::TimeTicks& start) { | |
694 if (!backend_.get()) | |
695 return; | |
696 | |
697 switch (op) { | |
698 case kRead: | |
699 CACHE_UMA(AGE_MS, "ReadTime", 0, start); | |
700 break; | |
701 case kWrite: | |
702 CACHE_UMA(AGE_MS, "WriteTime", 0, start); | |
703 break; | |
704 case kSparseRead: | |
705 CACHE_UMA(AGE_MS, "SparseReadTime", 0, start); | |
706 break; | |
707 case kSparseWrite: | |
708 CACHE_UMA(AGE_MS, "SparseWriteTime", 0, start); | |
709 break; | |
710 case kAsyncIO: | |
711 CACHE_UMA(AGE_MS, "AsyncIOTime", 0, start); | |
712 break; | |
713 case kReadAsync1: | |
714 CACHE_UMA(AGE_MS, "AsyncReadDispatchTime", 0, start); | |
715 break; | |
716 case kWriteAsync1: | |
717 CACHE_UMA(AGE_MS, "AsyncWriteDispatchTime", 0, start); | |
718 break; | |
719 default: | |
720 NOTREACHED(); | |
721 } | |
722 } | |
723 | |
724 void EntryImpl::BeginLogging(net::NetLog* net_log, bool created) { | |
725 DCHECK(!net_log_.net_log()); | |
726 net_log_ = net::BoundNetLog::Make( | |
727 net_log, net::NetLog::SOURCE_DISK_CACHE_ENTRY); | |
728 net_log_.BeginEvent( | |
729 net::NetLog::TYPE_DISK_CACHE_ENTRY_IMPL, | |
730 CreateNetLogEntryCreationCallback(this, created)); | |
731 } | |
732 | |
733 const net::BoundNetLog& EntryImpl::net_log() const { | |
734 return net_log_; | |
735 } | |
736 | |
737 // static | |
738 int EntryImpl::NumBlocksForEntry(int key_size) { | |
739 // The longest key that can be stored using one block. | |
740 int key1_len = | |
741 static_cast<int>(sizeof(EntryStore) - offsetof(EntryStore, key)); | |
742 | |
743 if (key_size < key1_len || key_size > kMaxInternalKeyLength) | |
744 return 1; | |
745 | |
746 return ((key_size - key1_len) / 256 + 2); | |
747 } | |
748 | |
749 // ------------------------------------------------------------------------ | |
750 | |
751 void EntryImpl::Doom() { | |
752 if (background_queue_.get()) | |
753 background_queue_->DoomEntryImpl(this); | |
754 } | |
755 | |
756 void EntryImpl::Close() { | |
757 if (background_queue_.get()) | |
758 background_queue_->CloseEntryImpl(this); | |
759 } | |
760 | |
761 std::string EntryImpl::GetKey() const { | |
762 CacheEntryBlock* entry = const_cast<CacheEntryBlock*>(&entry_); | |
763 int key_len = entry->Data()->key_len; | |
764 if (key_len <= kMaxInternalKeyLength) | |
765 return std::string(entry->Data()->key); | |
766 | |
767 // We keep a copy of the key so that we can always return it, even if the | |
768 // backend is disabled. | |
769 if (!key_.empty()) | |
770 return key_; | |
771 | |
772 Addr address(entry->Data()->long_key); | |
773 DCHECK(address.is_initialized()); | |
774 size_t offset = 0; | |
775 if (address.is_block_file()) | |
776 offset = address.start_block() * address.BlockSize() + kBlockHeaderSize; | |
777 | |
778 COMPILE_ASSERT(kNumStreams == kKeyFileIndex, invalid_key_index); | |
779 File* key_file = const_cast<EntryImpl*>(this)->GetBackingFile(address, | |
780 kKeyFileIndex); | |
781 if (!key_file) | |
782 return std::string(); | |
783 | |
784 ++key_len; // We store a trailing \0 on disk that we read back below. | |
785 if (!offset && key_file->GetLength() != static_cast<size_t>(key_len)) | |
786 return std::string(); | |
787 | |
788 if (!key_file->Read(WriteInto(&key_, key_len), key_len, offset)) | |
789 key_.clear(); | |
790 return key_; | |
791 } | |
792 | |
793 Time EntryImpl::GetLastUsed() const { | |
794 CacheRankingsBlock* node = const_cast<CacheRankingsBlock*>(&node_); | |
795 return Time::FromInternalValue(node->Data()->last_used); | |
796 } | |
797 | |
798 Time EntryImpl::GetLastModified() const { | |
799 CacheRankingsBlock* node = const_cast<CacheRankingsBlock*>(&node_); | |
800 return Time::FromInternalValue(node->Data()->last_modified); | |
801 } | |
802 | |
803 int32 EntryImpl::GetDataSize(int index) const { | |
804 if (index < 0 || index >= kNumStreams) | |
805 return 0; | |
806 | |
807 CacheEntryBlock* entry = const_cast<CacheEntryBlock*>(&entry_); | |
808 return entry->Data()->data_size[index]; | |
809 } | |
810 | |
811 int EntryImpl::ReadData(int index, int offset, IOBuffer* buf, int buf_len, | |
812 const CompletionCallback& callback) { | |
813 if (callback.is_null()) | |
814 return ReadDataImpl(index, offset, buf, buf_len, callback); | |
815 | |
816 DCHECK(node_.Data()->dirty || read_only_); | |
817 if (index < 0 || index >= kNumStreams) | |
818 return net::ERR_INVALID_ARGUMENT; | |
819 | |
820 int entry_size = entry_.Data()->data_size[index]; | |
821 if (offset >= entry_size || offset < 0 || !buf_len) | |
822 return 0; | |
823 | |
824 if (buf_len < 0) | |
825 return net::ERR_INVALID_ARGUMENT; | |
826 | |
827 if (!background_queue_.get()) | |
828 return net::ERR_UNEXPECTED; | |
829 | |
830 background_queue_->ReadData(this, index, offset, buf, buf_len, callback); | |
831 return net::ERR_IO_PENDING; | |
832 } | |
833 | |
834 int EntryImpl::WriteData(int index, int offset, IOBuffer* buf, int buf_len, | |
835 const CompletionCallback& callback, bool truncate) { | |
836 if (callback.is_null()) | |
837 return WriteDataImpl(index, offset, buf, buf_len, callback, truncate); | |
838 | |
839 DCHECK(node_.Data()->dirty || read_only_); | |
840 if (index < 0 || index >= kNumStreams) | |
841 return net::ERR_INVALID_ARGUMENT; | |
842 | |
843 if (offset < 0 || buf_len < 0) | |
844 return net::ERR_INVALID_ARGUMENT; | |
845 | |
846 if (!background_queue_.get()) | |
847 return net::ERR_UNEXPECTED; | |
848 | |
849 background_queue_->WriteData(this, index, offset, buf, buf_len, truncate, | |
850 callback); | |
851 return net::ERR_IO_PENDING; | |
852 } | |
853 | |
854 int EntryImpl::ReadSparseData(int64 offset, IOBuffer* buf, int buf_len, | |
855 const CompletionCallback& callback) { | |
856 if (callback.is_null()) | |
857 return ReadSparseDataImpl(offset, buf, buf_len, callback); | |
858 | |
859 if (!background_queue_.get()) | |
860 return net::ERR_UNEXPECTED; | |
861 | |
862 background_queue_->ReadSparseData(this, offset, buf, buf_len, callback); | |
863 return net::ERR_IO_PENDING; | |
864 } | |
865 | |
866 int EntryImpl::WriteSparseData(int64 offset, IOBuffer* buf, int buf_len, | |
867 const CompletionCallback& callback) { | |
868 if (callback.is_null()) | |
869 return WriteSparseDataImpl(offset, buf, buf_len, callback); | |
870 | |
871 if (!background_queue_.get()) | |
872 return net::ERR_UNEXPECTED; | |
873 | |
874 background_queue_->WriteSparseData(this, offset, buf, buf_len, callback); | |
875 return net::ERR_IO_PENDING; | |
876 } | |
877 | |
878 int EntryImpl::GetAvailableRange(int64 offset, int len, int64* start, | |
879 const CompletionCallback& callback) { | |
880 if (!background_queue_.get()) | |
881 return net::ERR_UNEXPECTED; | |
882 | |
883 background_queue_->GetAvailableRange(this, offset, len, start, callback); | |
884 return net::ERR_IO_PENDING; | |
885 } | |
886 | |
887 bool EntryImpl::CouldBeSparse() const { | |
888 if (sparse_.get()) | |
889 return true; | |
890 | |
891 scoped_ptr<SparseControl> sparse; | |
892 sparse.reset(new SparseControl(const_cast<EntryImpl*>(this))); | |
893 return sparse->CouldBeSparse(); | |
894 } | |
895 | |
896 void EntryImpl::CancelSparseIO() { | |
897 if (background_queue_.get()) | |
898 background_queue_->CancelSparseIO(this); | |
899 } | |
900 | |
901 int EntryImpl::ReadyForSparseIO(const CompletionCallback& callback) { | |
902 if (!sparse_.get()) | |
903 return net::OK; | |
904 | |
905 if (!background_queue_.get()) | |
906 return net::ERR_UNEXPECTED; | |
907 | |
908 background_queue_->ReadyForSparseIO(this, callback); | |
909 return net::ERR_IO_PENDING; | |
910 } | |
911 | |
912 // When an entry is deleted from the cache, we clean up all the data associated | |
913 // with it for two reasons: to simplify the reuse of the block (we know that any | |
914 // unused block is filled with zeros), and to simplify the handling of write / | |
915 // read partial information from an entry (don't have to worry about returning | |
916 // data related to a previous cache entry because the range was not fully | |
917 // written before). | |
918 EntryImpl::~EntryImpl() { | |
919 if (!backend_.get()) { | |
920 entry_.clear_modified(); | |
921 node_.clear_modified(); | |
922 return; | |
923 } | |
924 Log("~EntryImpl in"); | |
925 | |
926 // Save the sparse info to disk. This will generate IO for this entry and | |
927 // maybe for a child entry, so it is important to do it before deleting this | |
928 // entry. | |
929 sparse_.reset(); | |
930 | |
931 // Remove this entry from the list of open entries. | |
932 backend_->OnEntryDestroyBegin(entry_.address()); | |
933 | |
934 if (doomed_) { | |
935 DeleteEntryData(true); | |
936 } else { | |
937 #if defined(NET_BUILD_STRESS_CACHE) | |
938 SanityCheck(); | |
939 #endif | |
940 net_log_.AddEvent(net::NetLog::TYPE_ENTRY_CLOSE); | |
941 bool ret = true; | |
942 for (int index = 0; index < kNumStreams; index++) { | |
943 if (user_buffers_[index].get()) { | |
944 if (!(ret = Flush(index, 0))) | |
945 LOG(ERROR) << "Failed to save user data"; | |
946 } | |
947 if (unreported_size_[index]) { | |
948 backend_->ModifyStorageSize( | |
949 entry_.Data()->data_size[index] - unreported_size_[index], | |
950 entry_.Data()->data_size[index]); | |
951 } | |
952 } | |
953 | |
954 if (!ret) { | |
955 // There was a failure writing the actual data. Mark the entry as dirty. | |
956 int current_id = backend_->GetCurrentEntryId(); | |
957 node_.Data()->dirty = current_id == 1 ? -1 : current_id - 1; | |
958 node_.Store(); | |
959 } else if (node_.HasData() && !dirty_ && node_.Data()->dirty) { | |
960 node_.Data()->dirty = 0; | |
961 node_.Store(); | |
962 } | |
963 } | |
964 | |
965 Trace("~EntryImpl out 0x%p", reinterpret_cast<void*>(this)); | |
966 net_log_.EndEvent(net::NetLog::TYPE_DISK_CACHE_ENTRY_IMPL); | |
967 backend_->OnEntryDestroyEnd(); | |
968 } | |
969 | |
970 // ------------------------------------------------------------------------ | |
971 | |
972 int EntryImpl::InternalReadData(int index, int offset, | |
973 IOBuffer* buf, int buf_len, | |
974 const CompletionCallback& callback) { | |
975 DCHECK(node_.Data()->dirty || read_only_); | |
976 DVLOG(2) << "Read from " << index << " at " << offset << " : " << buf_len; | |
977 if (index < 0 || index >= kNumStreams) | |
978 return net::ERR_INVALID_ARGUMENT; | |
979 | |
980 int entry_size = entry_.Data()->data_size[index]; | |
981 if (offset >= entry_size || offset < 0 || !buf_len) | |
982 return 0; | |
983 | |
984 if (buf_len < 0) | |
985 return net::ERR_INVALID_ARGUMENT; | |
986 | |
987 if (!backend_.get()) | |
988 return net::ERR_UNEXPECTED; | |
989 | |
990 TimeTicks start = TimeTicks::Now(); | |
991 | |
992 if (offset + buf_len > entry_size) | |
993 buf_len = entry_size - offset; | |
994 | |
995 UpdateRank(false); | |
996 | |
997 backend_->OnEvent(Stats::READ_DATA); | |
998 backend_->OnRead(buf_len); | |
999 | |
1000 Addr address(entry_.Data()->data_addr[index]); | |
1001 int eof = address.is_initialized() ? entry_size : 0; | |
1002 if (user_buffers_[index].get() && | |
1003 user_buffers_[index]->PreRead(eof, offset, &buf_len)) { | |
1004 // Complete the operation locally. | |
1005 buf_len = user_buffers_[index]->Read(offset, buf, buf_len); | |
1006 ReportIOTime(kRead, start); | |
1007 return buf_len; | |
1008 } | |
1009 | |
1010 address.set_value(entry_.Data()->data_addr[index]); | |
1011 DCHECK(address.is_initialized()); | |
1012 if (!address.is_initialized()) { | |
1013 DoomImpl(); | |
1014 return net::ERR_FAILED; | |
1015 } | |
1016 | |
1017 File* file = GetBackingFile(address, index); | |
1018 if (!file) { | |
1019 DoomImpl(); | |
1020 LOG(ERROR) << "No file for " << std::hex << address.value(); | |
1021 return net::ERR_FILE_NOT_FOUND; | |
1022 } | |
1023 | |
1024 size_t file_offset = offset; | |
1025 if (address.is_block_file()) { | |
1026 DCHECK_LE(offset + buf_len, kMaxBlockSize); | |
1027 file_offset += address.start_block() * address.BlockSize() + | |
1028 kBlockHeaderSize; | |
1029 } | |
1030 | |
1031 SyncCallback* io_callback = NULL; | |
1032 if (!callback.is_null()) { | |
1033 io_callback = new SyncCallback(this, buf, callback, | |
1034 net::NetLog::TYPE_ENTRY_READ_DATA); | |
1035 } | |
1036 | |
1037 TimeTicks start_async = TimeTicks::Now(); | |
1038 | |
1039 bool completed; | |
1040 if (!file->Read(buf->data(), buf_len, file_offset, io_callback, &completed)) { | |
1041 if (io_callback) | |
1042 io_callback->Discard(); | |
1043 DoomImpl(); | |
1044 return net::ERR_CACHE_READ_FAILURE; | |
1045 } | |
1046 | |
1047 if (io_callback && completed) | |
1048 io_callback->Discard(); | |
1049 | |
1050 if (io_callback) | |
1051 ReportIOTime(kReadAsync1, start_async); | |
1052 | |
1053 ReportIOTime(kRead, start); | |
1054 return (completed || callback.is_null()) ? buf_len : net::ERR_IO_PENDING; | |
1055 } | |
1056 | |
1057 int EntryImpl::InternalWriteData(int index, int offset, | |
1058 IOBuffer* buf, int buf_len, | |
1059 const CompletionCallback& callback, | |
1060 bool truncate) { | |
1061 DCHECK(node_.Data()->dirty || read_only_); | |
1062 DVLOG(2) << "Write to " << index << " at " << offset << " : " << buf_len; | |
1063 if (index < 0 || index >= kNumStreams) | |
1064 return net::ERR_INVALID_ARGUMENT; | |
1065 | |
1066 if (offset < 0 || buf_len < 0) | |
1067 return net::ERR_INVALID_ARGUMENT; | |
1068 | |
1069 if (!backend_.get()) | |
1070 return net::ERR_UNEXPECTED; | |
1071 | |
1072 int max_file_size = backend_->MaxFileSize(); | |
1073 | |
1074 // offset or buf_len could be negative numbers. | |
1075 if (offset > max_file_size || buf_len > max_file_size || | |
1076 offset + buf_len > max_file_size) { | |
1077 int size = offset + buf_len; | |
1078 if (size <= max_file_size) | |
1079 size = kint32max; | |
1080 backend_->TooMuchStorageRequested(size); | |
1081 return net::ERR_FAILED; | |
1082 } | |
1083 | |
1084 TimeTicks start = TimeTicks::Now(); | |
1085 | |
1086 // Read the size at this point (it may change inside prepare). | |
1087 int entry_size = entry_.Data()->data_size[index]; | |
1088 bool extending = entry_size < offset + buf_len; | |
1089 truncate = truncate && entry_size > offset + buf_len; | |
1090 Trace("To PrepareTarget 0x%x", entry_.address().value()); | |
1091 if (!PrepareTarget(index, offset, buf_len, truncate)) | |
1092 return net::ERR_FAILED; | |
1093 | |
1094 Trace("From PrepareTarget 0x%x", entry_.address().value()); | |
1095 if (extending || truncate) | |
1096 UpdateSize(index, entry_size, offset + buf_len); | |
1097 | |
1098 UpdateRank(true); | |
1099 | |
1100 backend_->OnEvent(Stats::WRITE_DATA); | |
1101 backend_->OnWrite(buf_len); | |
1102 | |
1103 if (user_buffers_[index].get()) { | |
1104 // Complete the operation locally. | |
1105 user_buffers_[index]->Write(offset, buf, buf_len); | |
1106 ReportIOTime(kWrite, start); | |
1107 return buf_len; | |
1108 } | |
1109 | |
1110 Addr address(entry_.Data()->data_addr[index]); | |
1111 if (offset + buf_len == 0) { | |
1112 if (truncate) { | |
1113 DCHECK(!address.is_initialized()); | |
1114 } | |
1115 return 0; | |
1116 } | |
1117 | |
1118 File* file = GetBackingFile(address, index); | |
1119 if (!file) | |
1120 return net::ERR_FILE_NOT_FOUND; | |
1121 | |
1122 size_t file_offset = offset; | |
1123 if (address.is_block_file()) { | |
1124 DCHECK_LE(offset + buf_len, kMaxBlockSize); | |
1125 file_offset += address.start_block() * address.BlockSize() + | |
1126 kBlockHeaderSize; | |
1127 } else if (truncate || (extending && !buf_len)) { | |
1128 if (!file->SetLength(offset + buf_len)) | |
1129 return net::ERR_FAILED; | |
1130 } | |
1131 | |
1132 if (!buf_len) | |
1133 return 0; | |
1134 | |
1135 SyncCallback* io_callback = NULL; | |
1136 if (!callback.is_null()) { | |
1137 io_callback = new SyncCallback(this, buf, callback, | |
1138 net::NetLog::TYPE_ENTRY_WRITE_DATA); | |
1139 } | |
1140 | |
1141 TimeTicks start_async = TimeTicks::Now(); | |
1142 | |
1143 bool completed; | |
1144 if (!file->Write(buf->data(), buf_len, file_offset, io_callback, | |
1145 &completed)) { | |
1146 if (io_callback) | |
1147 io_callback->Discard(); | |
1148 return net::ERR_CACHE_WRITE_FAILURE; | |
1149 } | |
1150 | |
1151 if (io_callback && completed) | |
1152 io_callback->Discard(); | |
1153 | |
1154 if (io_callback) | |
1155 ReportIOTime(kWriteAsync1, start_async); | |
1156 | |
1157 ReportIOTime(kWrite, start); | |
1158 return (completed || callback.is_null()) ? buf_len : net::ERR_IO_PENDING; | |
1159 } | |
1160 | |
1161 // ------------------------------------------------------------------------ | |
1162 | |
1163 bool EntryImpl::CreateDataBlock(int index, int size) { | |
1164 DCHECK(index >= 0 && index < kNumStreams); | |
1165 | |
1166 Addr address(entry_.Data()->data_addr[index]); | |
1167 if (!CreateBlock(size, &address)) | |
1168 return false; | |
1169 | |
1170 entry_.Data()->data_addr[index] = address.value(); | |
1171 entry_.Store(); | |
1172 return true; | |
1173 } | |
1174 | |
1175 bool EntryImpl::CreateBlock(int size, Addr* address) { | |
1176 DCHECK(!address->is_initialized()); | |
1177 if (!backend_.get()) | |
1178 return false; | |
1179 | |
1180 FileType file_type = Addr::RequiredFileType(size); | |
1181 if (EXTERNAL == file_type) { | |
1182 if (size > backend_->MaxFileSize()) | |
1183 return false; | |
1184 if (!backend_->CreateExternalFile(address)) | |
1185 return false; | |
1186 } else { | |
1187 int num_blocks = Addr::RequiredBlocks(size, file_type); | |
1188 | |
1189 if (!backend_->CreateBlock(file_type, num_blocks, address)) | |
1190 return false; | |
1191 } | |
1192 return true; | |
1193 } | |
1194 | |
1195 // Note that this method may end up modifying a block file so upon return the | |
1196 // involved block will be free, and could be reused for something else. If there | |
1197 // is a crash after that point (and maybe before returning to the caller), the | |
1198 // entry will be left dirty... and at some point it will be discarded; it is | |
1199 // important that the entry doesn't keep a reference to this address, or we'll | |
1200 // end up deleting the contents of |address| once again. | |
1201 void EntryImpl::DeleteData(Addr address, int index) { | |
1202 DCHECK(backend_.get()); | |
1203 if (!address.is_initialized()) | |
1204 return; | |
1205 if (address.is_separate_file()) { | |
1206 int failure = !DeleteCacheFile(backend_->GetFileName(address)); | |
1207 CACHE_UMA(COUNTS, "DeleteFailed", 0, failure); | |
1208 if (failure) { | |
1209 LOG(ERROR) << "Failed to delete " << | |
1210 backend_->GetFileName(address).value() << " from the cache."; | |
1211 } | |
1212 if (files_[index].get()) | |
1213 files_[index] = NULL; // Releases the object. | |
1214 } else { | |
1215 backend_->DeleteBlock(address, true); | |
1216 } | |
1217 } | |
1218 | |
1219 void EntryImpl::UpdateRank(bool modified) { | |
1220 if (!backend_.get()) | |
1221 return; | |
1222 | |
1223 if (!doomed_) { | |
1224 // Everything is handled by the backend. | |
1225 backend_->UpdateRank(this, modified); | |
1226 return; | |
1227 } | |
1228 | |
1229 Time current = Time::Now(); | |
1230 node_.Data()->last_used = current.ToInternalValue(); | |
1231 | |
1232 if (modified) | |
1233 node_.Data()->last_modified = current.ToInternalValue(); | |
1234 } | |
1235 | |
1236 File* EntryImpl::GetBackingFile(Addr address, int index) { | |
1237 if (!backend_.get()) | |
1238 return NULL; | |
1239 | |
1240 File* file; | |
1241 if (address.is_separate_file()) | |
1242 file = GetExternalFile(address, index); | |
1243 else | |
1244 file = backend_->File(address); | |
1245 return file; | |
1246 } | |
1247 | |
1248 File* EntryImpl::GetExternalFile(Addr address, int index) { | |
1249 DCHECK(index >= 0 && index <= kKeyFileIndex); | |
1250 if (!files_[index].get()) { | |
1251 // For a key file, use mixed mode IO. | |
1252 scoped_refptr<File> file(new File(kKeyFileIndex == index)); | |
1253 if (file->Init(backend_->GetFileName(address))) | |
1254 files_[index].swap(file); | |
1255 } | |
1256 return files_[index].get(); | |
1257 } | |
1258 | |
1259 // We keep a memory buffer for everything that ends up stored on a block file | |
1260 // (because we don't know yet the final data size), and for some of the data | |
1261 // that end up on external files. This function will initialize that memory | |
1262 // buffer and / or the files needed to store the data. | |
1263 // | |
1264 // In general, a buffer may overlap data already stored on disk, and in that | |
1265 // case, the contents of the buffer are the most accurate. It may also extend | |
1266 // the file, but we don't want to read from disk just to keep the buffer up to | |
1267 // date. This means that as soon as there is a chance to get confused about what | |
1268 // is the most recent version of some part of a file, we'll flush the buffer and | |
1269 // reuse it for the new data. Keep in mind that the normal use pattern is quite | |
1270 // simple (write sequentially from the beginning), so we optimize for handling | |
1271 // that case. | |
1272 bool EntryImpl::PrepareTarget(int index, int offset, int buf_len, | |
1273 bool truncate) { | |
1274 if (truncate) | |
1275 return HandleTruncation(index, offset, buf_len); | |
1276 | |
1277 if (!offset && !buf_len) | |
1278 return true; | |
1279 | |
1280 Addr address(entry_.Data()->data_addr[index]); | |
1281 if (address.is_initialized()) { | |
1282 if (address.is_block_file() && !MoveToLocalBuffer(index)) | |
1283 return false; | |
1284 | |
1285 if (!user_buffers_[index].get() && offset < kMaxBlockSize) { | |
1286 // We are about to create a buffer for the first 16KB, make sure that we | |
1287 // preserve existing data. | |
1288 if (!CopyToLocalBuffer(index)) | |
1289 return false; | |
1290 } | |
1291 } | |
1292 | |
1293 if (!user_buffers_[index].get()) | |
1294 user_buffers_[index].reset(new UserBuffer(backend_.get())); | |
1295 | |
1296 return PrepareBuffer(index, offset, buf_len); | |
1297 } | |
1298 | |
1299 // We get to this function with some data already stored. If there is a | |
1300 // truncation that results on data stored internally, we'll explicitly | |
1301 // handle the case here. | |
1302 bool EntryImpl::HandleTruncation(int index, int offset, int buf_len) { | |
1303 Addr address(entry_.Data()->data_addr[index]); | |
1304 | |
1305 int current_size = entry_.Data()->data_size[index]; | |
1306 int new_size = offset + buf_len; | |
1307 | |
1308 if (!new_size) { | |
1309 // This is by far the most common scenario. | |
1310 backend_->ModifyStorageSize(current_size - unreported_size_[index], 0); | |
1311 entry_.Data()->data_addr[index] = 0; | |
1312 entry_.Data()->data_size[index] = 0; | |
1313 unreported_size_[index] = 0; | |
1314 entry_.Store(); | |
1315 DeleteData(address, index); | |
1316 | |
1317 user_buffers_[index].reset(); | |
1318 return true; | |
1319 } | |
1320 | |
1321 // We never postpone truncating a file, if there is one, but we may postpone | |
1322 // telling the backend about the size reduction. | |
1323 if (user_buffers_[index].get()) { | |
1324 DCHECK_GE(current_size, user_buffers_[index]->Start()); | |
1325 if (!address.is_initialized()) { | |
1326 // There is no overlap between the buffer and disk. | |
1327 if (new_size > user_buffers_[index]->Start()) { | |
1328 // Just truncate our buffer. | |
1329 DCHECK_LT(new_size, user_buffers_[index]->End()); | |
1330 user_buffers_[index]->Truncate(new_size); | |
1331 return true; | |
1332 } | |
1333 | |
1334 // Just discard our buffer. | |
1335 user_buffers_[index]->Reset(); | |
1336 return PrepareBuffer(index, offset, buf_len); | |
1337 } | |
1338 | |
1339 // There is some overlap or we need to extend the file before the | |
1340 // truncation. | |
1341 if (offset > user_buffers_[index]->Start()) | |
1342 user_buffers_[index]->Truncate(new_size); | |
1343 UpdateSize(index, current_size, new_size); | |
1344 if (!Flush(index, 0)) | |
1345 return false; | |
1346 user_buffers_[index].reset(); | |
1347 } | |
1348 | |
1349 // We have data somewhere, and it is not in a buffer. | |
1350 DCHECK(!user_buffers_[index].get()); | |
1351 DCHECK(address.is_initialized()); | |
1352 | |
1353 if (new_size > kMaxBlockSize) | |
1354 return true; // Let the operation go directly to disk. | |
1355 | |
1356 return ImportSeparateFile(index, offset + buf_len); | |
1357 } | |
1358 | |
1359 bool EntryImpl::CopyToLocalBuffer(int index) { | |
1360 Addr address(entry_.Data()->data_addr[index]); | |
1361 DCHECK(!user_buffers_[index].get()); | |
1362 DCHECK(address.is_initialized()); | |
1363 | |
1364 int len = std::min(entry_.Data()->data_size[index], kMaxBlockSize); | |
1365 user_buffers_[index].reset(new UserBuffer(backend_.get())); | |
1366 user_buffers_[index]->Write(len, NULL, 0); | |
1367 | |
1368 File* file = GetBackingFile(address, index); | |
1369 int offset = 0; | |
1370 | |
1371 if (address.is_block_file()) | |
1372 offset = address.start_block() * address.BlockSize() + kBlockHeaderSize; | |
1373 | |
1374 if (!file || | |
1375 !file->Read(user_buffers_[index]->Data(), len, offset, NULL, NULL)) { | |
1376 user_buffers_[index].reset(); | |
1377 return false; | |
1378 } | |
1379 return true; | |
1380 } | |
1381 | |
1382 bool EntryImpl::MoveToLocalBuffer(int index) { | |
1383 if (!CopyToLocalBuffer(index)) | |
1384 return false; | |
1385 | |
1386 Addr address(entry_.Data()->data_addr[index]); | |
1387 entry_.Data()->data_addr[index] = 0; | |
1388 entry_.Store(); | |
1389 DeleteData(address, index); | |
1390 | |
1391 // If we lose this entry we'll see it as zero sized. | |
1392 int len = entry_.Data()->data_size[index]; | |
1393 backend_->ModifyStorageSize(len - unreported_size_[index], 0); | |
1394 unreported_size_[index] = len; | |
1395 return true; | |
1396 } | |
1397 | |
1398 bool EntryImpl::ImportSeparateFile(int index, int new_size) { | |
1399 if (entry_.Data()->data_size[index] > new_size) | |
1400 UpdateSize(index, entry_.Data()->data_size[index], new_size); | |
1401 | |
1402 return MoveToLocalBuffer(index); | |
1403 } | |
1404 | |
1405 bool EntryImpl::PrepareBuffer(int index, int offset, int buf_len) { | |
1406 DCHECK(user_buffers_[index].get()); | |
1407 if ((user_buffers_[index]->End() && offset > user_buffers_[index]->End()) || | |
1408 offset > entry_.Data()->data_size[index]) { | |
1409 // We are about to extend the buffer or the file (with zeros), so make sure | |
1410 // that we are not overwriting anything. | |
1411 Addr address(entry_.Data()->data_addr[index]); | |
1412 if (address.is_initialized() && address.is_separate_file()) { | |
1413 if (!Flush(index, 0)) | |
1414 return false; | |
1415 // There is an actual file already, and we don't want to keep track of | |
1416 // its length so we let this operation go straight to disk. | |
1417 // The only case when a buffer is allowed to extend the file (as in fill | |
1418 // with zeros before the start) is when there is no file yet to extend. | |
1419 user_buffers_[index].reset(); | |
1420 return true; | |
1421 } | |
1422 } | |
1423 | |
1424 if (!user_buffers_[index]->PreWrite(offset, buf_len)) { | |
1425 if (!Flush(index, offset + buf_len)) | |
1426 return false; | |
1427 | |
1428 // Lets try again. | |
1429 if (offset > user_buffers_[index]->End() || | |
1430 !user_buffers_[index]->PreWrite(offset, buf_len)) { | |
1431 // We cannot complete the operation with a buffer. | |
1432 DCHECK(!user_buffers_[index]->Size()); | |
1433 DCHECK(!user_buffers_[index]->Start()); | |
1434 user_buffers_[index].reset(); | |
1435 } | |
1436 } | |
1437 return true; | |
1438 } | |
1439 | |
1440 bool EntryImpl::Flush(int index, int min_len) { | |
1441 Addr address(entry_.Data()->data_addr[index]); | |
1442 DCHECK(user_buffers_[index].get()); | |
1443 DCHECK(!address.is_initialized() || address.is_separate_file()); | |
1444 DVLOG(3) << "Flush"; | |
1445 | |
1446 int size = std::max(entry_.Data()->data_size[index], min_len); | |
1447 if (size && !address.is_initialized() && !CreateDataBlock(index, size)) | |
1448 return false; | |
1449 | |
1450 if (!entry_.Data()->data_size[index]) { | |
1451 DCHECK(!user_buffers_[index]->Size()); | |
1452 return true; | |
1453 } | |
1454 | |
1455 address.set_value(entry_.Data()->data_addr[index]); | |
1456 | |
1457 int len = user_buffers_[index]->Size(); | |
1458 int offset = user_buffers_[index]->Start(); | |
1459 if (!len && !offset) | |
1460 return true; | |
1461 | |
1462 if (address.is_block_file()) { | |
1463 DCHECK_EQ(len, entry_.Data()->data_size[index]); | |
1464 DCHECK(!offset); | |
1465 offset = address.start_block() * address.BlockSize() + kBlockHeaderSize; | |
1466 } | |
1467 | |
1468 File* file = GetBackingFile(address, index); | |
1469 if (!file) | |
1470 return false; | |
1471 | |
1472 if (!file->Write(user_buffers_[index]->Data(), len, offset, NULL, NULL)) | |
1473 return false; | |
1474 user_buffers_[index]->Reset(); | |
1475 | |
1476 return true; | |
1477 } | |
1478 | |
1479 void EntryImpl::UpdateSize(int index, int old_size, int new_size) { | |
1480 if (entry_.Data()->data_size[index] == new_size) | |
1481 return; | |
1482 | |
1483 unreported_size_[index] += new_size - old_size; | |
1484 entry_.Data()->data_size[index] = new_size; | |
1485 entry_.set_modified(); | |
1486 } | |
1487 | |
1488 int EntryImpl::InitSparseData() { | |
1489 if (sparse_.get()) | |
1490 return net::OK; | |
1491 | |
1492 // Use a local variable so that sparse_ never goes from 'valid' to NULL. | |
1493 scoped_ptr<SparseControl> sparse(new SparseControl(this)); | |
1494 int result = sparse->Init(); | |
1495 if (net::OK == result) | |
1496 sparse_.swap(sparse); | |
1497 | |
1498 return result; | |
1499 } | |
1500 | |
1501 void EntryImpl::SetEntryFlags(uint32 flags) { | |
1502 entry_.Data()->flags |= flags; | |
1503 entry_.set_modified(); | |
1504 } | |
1505 | |
1506 uint32 EntryImpl::GetEntryFlags() { | |
1507 return entry_.Data()->flags; | |
1508 } | |
1509 | |
1510 void EntryImpl::GetData(int index, char** buffer, Addr* address) { | |
1511 DCHECK(backend_.get()); | |
1512 if (user_buffers_[index].get() && user_buffers_[index]->Size() && | |
1513 !user_buffers_[index]->Start()) { | |
1514 // The data is already in memory, just copy it and we're done. | |
1515 int data_len = entry_.Data()->data_size[index]; | |
1516 if (data_len <= user_buffers_[index]->Size()) { | |
1517 DCHECK(!user_buffers_[index]->Start()); | |
1518 *buffer = new char[data_len]; | |
1519 memcpy(*buffer, user_buffers_[index]->Data(), data_len); | |
1520 return; | |
1521 } | |
1522 } | |
1523 | |
1524 // Bad news: we'd have to read the info from disk so instead we'll just tell | |
1525 // the caller where to read from. | |
1526 *buffer = NULL; | |
1527 address->set_value(entry_.Data()->data_addr[index]); | |
1528 if (address->is_initialized()) { | |
1529 // Prevent us from deleting the block from the backing store. | |
1530 backend_->ModifyStorageSize(entry_.Data()->data_size[index] - | |
1531 unreported_size_[index], 0); | |
1532 entry_.Data()->data_addr[index] = 0; | |
1533 entry_.Data()->data_size[index] = 0; | |
1534 } | |
1535 } | |
1536 | |
1537 void EntryImpl::Log(const char* msg) { | |
1538 int dirty = 0; | |
1539 if (node_.HasData()) { | |
1540 dirty = node_.Data()->dirty; | |
1541 } | |
1542 | |
1543 Trace("%s 0x%p 0x%x 0x%x", msg, reinterpret_cast<void*>(this), | |
1544 entry_.address().value(), node_.address().value()); | |
1545 | |
1546 Trace(" data: 0x%x 0x%x 0x%x", entry_.Data()->data_addr[0], | |
1547 entry_.Data()->data_addr[1], entry_.Data()->long_key); | |
1548 | |
1549 Trace(" doomed: %d 0x%x", doomed_, dirty); | |
1550 } | |
1551 | |
1552 } // namespace disk_cache | |
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