13345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick// Copyright (c) 2006-2010 The Chromium Authors. All rights reserved. 2c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Use of this source code is governed by a BSD-style license that can be 3c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// found in the LICENSE file. 4c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 5c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "net/disk_cache/block_files.h" 6c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 7c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "base/file_util.h" 8731df977c0511bca2206b5f333555b1205ff1f43Iain Merrick#include "base/metrics/histogram.h" 9c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "base/string_util.h" 103345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#include "base/stringprintf.h" 113f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen#include "base/threading/thread_checker.h" 12c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "base/time.h" 13c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "net/disk_cache/cache_util.h" 14c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "net/disk_cache/file_lock.h" 153345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#include "net/disk_cache/trace.h" 16c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 17c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdochusing base::TimeTicks; 18c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 19c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottnamespace { 20c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 21c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottconst char* kBlockName = "data_"; 22c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 23c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// This array is used to perform a fast lookup of the nibble bit pattern to the 24c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// type of entry that can be stored there (number of consecutive blocks). 25c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottconst char s_types[16] = {4, 3, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0}; 26c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 27c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Returns the type of block (number of consecutive blocks that can be stored) 28c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// for a given nibble of the bitmap. 29c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottinline int GetMapBlockType(uint8 value) { 30c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott value &= 0xf; 31c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return s_types[value]; 32c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 33c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 34c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottvoid FixAllocationCounters(disk_cache::BlockFileHeader* header); 35c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 36c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Creates a new entry on the allocation map, updating the apropriate counters. 37c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// target is the type of block to use (number of empty blocks), and size is the 38c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// actual number of blocks to use. 39c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottbool CreateMapBlock(int target, int size, disk_cache::BlockFileHeader* header, 40c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int* index) { 41c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (target <= 0 || target > disk_cache::kMaxNumBlocks || 42c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott size <= 0 || size > disk_cache::kMaxNumBlocks) { 43c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott NOTREACHED(); 44c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 45c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 46c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 47c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch TimeTicks start = TimeTicks::Now(); 48c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // We are going to process the map on 32-block chunks (32 bits), and on every 49c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // chunk, iterate through the 8 nibbles where the new block can be located. 50c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int current = header->hints[target - 1]; 51c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott for (int i = 0; i < header->max_entries / 32; i++, current++) { 52c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (current == header->max_entries / 32) 53c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott current = 0; 54c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott uint32 map_block = header->allocation_map[current]; 55c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 56c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott for (int j = 0; j < 8; j++, map_block >>= 4) { 57c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (GetMapBlockType(map_block) != target) 58c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott continue; 59c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 60c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott disk_cache::FileLock lock(header); 61c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int index_offset = j * 4 + 4 - target; 62c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott *index = current * 32 + index_offset; 633345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick DCHECK_EQ(*index / 4, (*index + size - 1) / 4); 64c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott uint32 to_add = ((1 << size) - 1) << index_offset; 65c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->allocation_map[current] |= to_add; 66c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 67c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->hints[target - 1] = current; 68c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->empty[target - 1]--; 69c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(header->empty[target - 1] >= 0); 70c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->num_entries++; 71c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (target != size) { 72c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->empty[target - size - 1]++; 73c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 74c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch HISTOGRAM_TIMES("DiskCache.CreateBlock", TimeTicks::Now() - start); 75c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return true; 76c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 77c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 78c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 79c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // It is possible to have an undetected corruption (for example when the OS 80c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // crashes), fix it here. 81c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott LOG(ERROR) << "Failing CreateMapBlock"; 82c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FixAllocationCounters(header); 83c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 84c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 85c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 86c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Deletes the block pointed by index from allocation_map, and updates the 87c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// relevant counters on the header. 88c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottvoid DeleteMapBlock(int index, int size, disk_cache::BlockFileHeader* header) { 89c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (size < 0 || size > disk_cache::kMaxNumBlocks) { 90c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott NOTREACHED(); 91c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return; 92c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 93c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch TimeTicks start = TimeTicks::Now(); 94c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int byte_index = index / 8; 95c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott uint8* byte_map = reinterpret_cast<uint8*>(header->allocation_map); 96c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott uint8 map_block = byte_map[byte_index]; 97c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 98c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (index % 8 >= 4) 99c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott map_block >>= 4; 100c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 101c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // See what type of block will be availabe after we delete this one. 102c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int bits_at_end = 4 - size - index % 4; 103c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott uint8 end_mask = (0xf << (4 - bits_at_end)) & 0xf; 104c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool update_counters = (map_block & end_mask) == 0; 105c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott uint8 new_value = map_block & ~(((1 << size) - 1) << (index % 4)); 106c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int new_type = GetMapBlockType(new_value); 107c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 108c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott disk_cache::FileLock lock(header); 109c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK((((1 << size) - 1) << (index % 8)) < 0x100); 110c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott uint8 to_clear = ((1 << size) - 1) << (index % 8); 111c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK((byte_map[byte_index] & to_clear) == to_clear); 112c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott byte_map[byte_index] &= ~to_clear; 113c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 114c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (update_counters) { 115c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (bits_at_end) 116c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->empty[bits_at_end - 1]--; 117c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->empty[new_type - 1]++; 118c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(header->empty[bits_at_end - 1] >= 0); 119c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 120c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->num_entries--; 121c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(header->num_entries >= 0); 122c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch HISTOGRAM_TIMES("DiskCache.DeleteBlock", TimeTicks::Now() - start); 123c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 124c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 125731df977c0511bca2206b5f333555b1205ff1f43Iain Merrick#ifndef NDEBUG 1263345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick// Returns true if the specified block is used. Note that this is a simplified 1273345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick// version of DeleteMapBlock(). 1283345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrickbool UsedMapBlock(int index, int size, disk_cache::BlockFileHeader* header) { 1293345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick if (size < 0 || size > disk_cache::kMaxNumBlocks) { 1303345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick NOTREACHED(); 1313345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick return false; 1323345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick } 1333345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick int byte_index = index / 8; 1343345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick uint8* byte_map = reinterpret_cast<uint8*>(header->allocation_map); 1353345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick uint8 map_block = byte_map[byte_index]; 1363345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 1373345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick if (index % 8 >= 4) 1383345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick map_block >>= 4; 1393345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 1403345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick DCHECK((((1 << size) - 1) << (index % 8)) < 0x100); 1413345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick uint8 to_clear = ((1 << size) - 1) << (index % 8); 1423345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick return ((byte_map[byte_index] & to_clear) == to_clear); 1433345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick} 144731df977c0511bca2206b5f333555b1205ff1f43Iain Merrick#endif // NDEBUG 1453345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 146c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Restores the "empty counters" and allocation hints. 147c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottvoid FixAllocationCounters(disk_cache::BlockFileHeader* header) { 148c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott for (int i = 0; i < disk_cache::kMaxNumBlocks; i++) { 149c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->hints[i] = 0; 150c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->empty[i] = 0; 151c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 152c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 153c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott for (int i = 0; i < header->max_entries / 32; i++) { 154c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott uint32 map_block = header->allocation_map[i]; 155c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 156c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott for (int j = 0; j < 8; j++, map_block >>= 4) { 157c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int type = GetMapBlockType(map_block); 158c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (type) 159c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->empty[type -1]++; 160c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 161c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 162c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 163c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 164c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Returns true if the current block file should not be used as-is to store more 165c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// records. |block_count| is the number of blocks to allocate. 166c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottbool NeedToGrowBlockFile(const disk_cache::BlockFileHeader* header, 167c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int block_count) { 168c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott bool have_space = false; 169c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int empty_blocks = 0; 170c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott for (int i = 0; i < disk_cache::kMaxNumBlocks; i++) { 171c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott empty_blocks += header->empty[i] * (i + 1); 172c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (i >= block_count - 1 && header->empty[i]) 173c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott have_space = true; 174c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 175c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 176c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (header->next_file && (empty_blocks < disk_cache::kMaxBlocks / 10)) { 177c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // This file is almost full but we already created another one, don't use 178c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // this file yet so that it is easier to find empty blocks when we start 179c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // using this file again. 180c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return true; 181c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 182c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return !have_space; 183c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 184c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 185c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} // namespace 186c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 187c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottnamespace disk_cache { 188c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 1893345a6884c488ff3a535c2c9acdd33d74b37e311Iain MerrickBlockFiles::BlockFiles(const FilePath& path) 1903345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick : init_(false), zero_buffer_(NULL), path_(path) { 1913345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick} 1923345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 193c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick ScottBlockFiles::~BlockFiles() { 194c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (zero_buffer_) 195c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott delete[] zero_buffer_; 196c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott CloseFiles(); 197c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 198c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 199c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottbool BlockFiles::Init(bool create_files) { 200c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(!init_); 201c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (init_) 202c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 203c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 2043f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen thread_checker_.reset(new base::ThreadChecker); 2053345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 206c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch block_files_.resize(kFirstAdditionalBlockFile); 207c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch for (int i = 0; i < kFirstAdditionalBlockFile; i++) { 208c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (create_files) 209c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!CreateBlockFile(i, static_cast<FileType>(i + 1), true)) 210c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 211c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 212c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!OpenBlockFile(i)) 213c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 214c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 215c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Walk this chain of files removing empty ones. 216c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott RemoveEmptyFile(static_cast<FileType>(i + 1)); 217c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 218c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 219c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott init_ = true; 220c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return true; 221c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 222c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 22372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian MonsenMappedFile* BlockFiles::GetFile(Addr address) { 22472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen DCHECK(thread_checker_->CalledOnValidThread()); 22572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen DCHECK(block_files_.size() >= 4); 22672a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen DCHECK(address.is_block_file() || !address.is_initialized()); 22772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!address.is_initialized()) 22872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return NULL; 22972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 23072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen int file_index = address.FileNumber(); 23172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (static_cast<unsigned int>(file_index) >= block_files_.size() || 23272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen !block_files_[file_index]) { 23372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen // We need to open the file 23472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!OpenBlockFile(file_index)) 23572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return NULL; 23672a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen } 23772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen DCHECK(block_files_.size() >= static_cast<unsigned int>(file_index)); 23872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return block_files_[file_index]; 23972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen} 24072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 24172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsenbool BlockFiles::CreateBlock(FileType block_type, int block_count, 24272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen Addr* block_address) { 24372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen DCHECK(thread_checker_->CalledOnValidThread()); 24472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (block_type < RANKINGS || block_type > BLOCK_4K || 24572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen block_count < 1 || block_count > 4) 24672a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return false; 24772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!init_) 24872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return false; 24972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 25072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen MappedFile* file = FileForNewBlock(block_type, block_count); 25172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!file) 25272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return false; 25372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 25472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen BlockFileHeader* header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 25572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 25672a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen int target_size = 0; 25772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen for (int i = block_count; i <= 4; i++) { 25872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (header->empty[i - 1]) { 25972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen target_size = i; 26072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen break; 26172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen } 26272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen } 26372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 26472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen DCHECK(target_size); 26572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen int index; 26672a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!CreateMapBlock(target_size, block_count, header, &index)) 26772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return false; 26872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 26972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen Addr address(block_type, block_count, header->this_file, index); 27072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen block_address->set_value(address.value()); 27172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen Trace("CreateBlock 0x%x", address.value()); 27272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return true; 27372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen} 27472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 27572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsenvoid BlockFiles::DeleteBlock(Addr address, bool deep) { 27672a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen DCHECK(thread_checker_->CalledOnValidThread()); 27772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!address.is_initialized() || address.is_separate_file()) 27872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return; 27972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 28072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!zero_buffer_) { 28172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen zero_buffer_ = new char[Addr::BlockSizeForFileType(BLOCK_4K) * 4]; 28272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen memset(zero_buffer_, 0, Addr::BlockSizeForFileType(BLOCK_4K) * 4); 28372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen } 28472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen MappedFile* file = GetFile(address); 28572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!file) 28672a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen return; 28772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 28872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen Trace("DeleteBlock 0x%x", address.value()); 28972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 29072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen size_t size = address.BlockSize() * address.num_blocks(); 29172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen size_t offset = address.start_block() * address.BlockSize() + 29272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen kBlockHeaderSize; 29372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (deep) 29472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen file->Write(zero_buffer_, size, offset); 29572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 296ae2796cabb52f6a27c50818b78107d3ebc858e0cKristian Monsen BlockFileHeader* header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 297ae2796cabb52f6a27c50818b78107d3ebc858e0cKristian Monsen DeleteMapBlock(address.start_block(), address.num_blocks(), header); 298ae2796cabb52f6a27c50818b78107d3ebc858e0cKristian Monsen 29972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (!header->num_entries) { 30072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen // This file is now empty. Let's try to delete it. 30172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen FileType type = Addr::RequiredFileType(header->entry_size); 30272a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen if (Addr::BlockSizeForFileType(RANKINGS) == header->entry_size) 30372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen type = RANKINGS; 30472a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen RemoveEmptyFile(type); 30572a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen } 30672a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen} 30772a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 308c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottvoid BlockFiles::CloseFiles() { 3093345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick if (init_) { 3103345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick DCHECK(thread_checker_->CalledOnValidThread()); 3113345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick } 312c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott init_ = false; 313c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott for (unsigned int i = 0; i < block_files_.size(); i++) { 314c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (block_files_[i]) { 315c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott block_files_[i]->Release(); 316c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott block_files_[i] = NULL; 317c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 318c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 319c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott block_files_.clear(); 320c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 321c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 322c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdochvoid BlockFiles::ReportStats() { 3233345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick DCHECK(thread_checker_->CalledOnValidThread()); 324c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch int used_blocks[kFirstAdditionalBlockFile]; 325c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch int load[kFirstAdditionalBlockFile]; 326c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch for (int i = 0; i < kFirstAdditionalBlockFile; i++) { 327c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch GetFileStats(i, &used_blocks[i], &load[i]); 328c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch } 329c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch UMA_HISTOGRAM_COUNTS("DiskCache.Blocks_0", used_blocks[0]); 330c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch UMA_HISTOGRAM_COUNTS("DiskCache.Blocks_1", used_blocks[1]); 331c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch UMA_HISTOGRAM_COUNTS("DiskCache.Blocks_2", used_blocks[2]); 332c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch UMA_HISTOGRAM_COUNTS("DiskCache.Blocks_3", used_blocks[3]); 333c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 334c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch UMA_HISTOGRAM_ENUMERATION("DiskCache.BlockLoad_0", load[0], 101); 335c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch UMA_HISTOGRAM_ENUMERATION("DiskCache.BlockLoad_1", load[1], 101); 336c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch UMA_HISTOGRAM_ENUMERATION("DiskCache.BlockLoad_2", load[2], 101); 337c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch UMA_HISTOGRAM_ENUMERATION("DiskCache.BlockLoad_3", load[3], 101); 338c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 339c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 3403345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrickbool BlockFiles::IsValid(Addr address) { 3413345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#ifdef NDEBUG 3423345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick return true; 3433345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#else 3443345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick if (!address.is_initialized() || address.is_separate_file()) 3453345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick return false; 3463345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 3473345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick MappedFile* file = GetFile(address); 3483345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick if (!file) 3493345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick return false; 3503345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 3513345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick BlockFileHeader* header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 3523345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick bool rv = UsedMapBlock(address.start_block(), address.num_blocks(), header); 3533345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick DCHECK(rv); 3543345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 3553345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick static bool read_contents = false; 3563345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick if (read_contents) { 3573345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick scoped_array<char> buffer; 3583345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick buffer.reset(new char[Addr::BlockSizeForFileType(BLOCK_4K) * 4]); 3593345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick size_t size = address.BlockSize() * address.num_blocks(); 3603345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick size_t offset = address.start_block() * address.BlockSize() + 3613345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick kBlockHeaderSize; 3623345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick bool ok = file->Read(buffer.get(), size, offset); 3633345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick DCHECK(ok); 3643345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick } 3653345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 3663345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick return rv; 3673345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#endif 3683345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick} 3693345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 370c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottbool BlockFiles::CreateBlockFile(int index, FileType file_type, bool force) { 371c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FilePath name = Name(index); 372c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int flags = 373c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott force ? base::PLATFORM_FILE_CREATE_ALWAYS : base::PLATFORM_FILE_CREATE; 374c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott flags |= base::PLATFORM_FILE_WRITE | base::PLATFORM_FILE_EXCLUSIVE_WRITE; 375c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 376c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott scoped_refptr<File> file(new File( 3773345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick base::CreatePlatformFile(name, flags, NULL, NULL))); 378c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!file->IsValid()) 379c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 380c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 381c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott BlockFileHeader header; 382c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header.entry_size = Addr::BlockSizeForFileType(file_type); 383c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header.this_file = static_cast<int16>(index); 384c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(index <= kint16max && index >= 0); 385c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 386c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return file->Write(&header, sizeof(header), 0); 387c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 388c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 389c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottbool BlockFiles::OpenBlockFile(int index) { 390c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (block_files_.size() - 1 < static_cast<unsigned int>(index)) { 391c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(index > 0); 392c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int to_add = index - static_cast<int>(block_files_.size()) + 1; 393c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott block_files_.resize(block_files_.size() + to_add); 394c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 395c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 396c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FilePath name = Name(index); 397c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott scoped_refptr<MappedFile> file(new MappedFile()); 398c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 399c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!file->Init(name, kBlockHeaderSize)) { 400c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott LOG(ERROR) << "Failed to open " << name.value(); 401c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 402c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 403c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 404c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch size_t file_len = file->GetLength(); 405c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch if (file_len < static_cast<size_t>(kBlockHeaderSize)) { 406c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott LOG(ERROR) << "File too small " << name.value(); 407c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 408c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 409c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 410c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott BlockFileHeader* header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 411c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (kBlockMagic != header->magic || kCurrentVersion != header->version) { 412c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott LOG(ERROR) << "Invalid file version or magic"; 413c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 414c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 415c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 416c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (header->updating) { 417c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Last instance was not properly shutdown. 418c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!FixBlockFileHeader(file)) 419c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 420c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 421c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 422d129b9e5870dc7fa49745121bf987e1b6ead1b51Kristian Monsen if (static_cast<int>(file_len) < 423d129b9e5870dc7fa49745121bf987e1b6ead1b51Kristian Monsen header->max_entries * header->entry_size + kBlockHeaderSize) { 424d129b9e5870dc7fa49745121bf987e1b6ead1b51Kristian Monsen LOG(ERROR) << "File too small " << name.value(); 425d129b9e5870dc7fa49745121bf987e1b6ead1b51Kristian Monsen return false; 426d129b9e5870dc7fa49745121bf987e1b6ead1b51Kristian Monsen } 427d129b9e5870dc7fa49745121bf987e1b6ead1b51Kristian Monsen 428c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch if (index == 0) { 429c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Load the links file into memory with a single read. 430c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch scoped_array<char> buf(new char[file_len]); 431c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch if (!file->Read(buf.get(), file_len, 0)) 432c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch return false; 433c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch } 434c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 435c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(!block_files_[index]); 436c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott file.swap(&block_files_[index]); 437c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return true; 438c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 439c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 440c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottbool BlockFiles::GrowBlockFile(MappedFile* file, BlockFileHeader* header) { 441c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (kMaxBlocks == header->max_entries) 442c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 443c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 444c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(!header->empty[3]); 445c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int new_size = header->max_entries + 1024; 446c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (new_size > kMaxBlocks) 447c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott new_size = kMaxBlocks; 448c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 449c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int new_size_bytes = new_size * header->entry_size + sizeof(*header); 450c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 451c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FileLock lock(header); 452c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!file->SetLength(new_size_bytes)) { 453c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Most likely we are trying to truncate the file, so the header is wrong. 454c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (header->updating < 10 && !FixBlockFileHeader(file)) { 455c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // If we can't fix the file increase the lock guard so we'll pick it on 456c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // the next start and replace it. 457c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->updating = 100; 458c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 459c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 460c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return (header->max_entries >= new_size); 461c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 462c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 463c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->empty[3] = (new_size - header->max_entries) / 4; // 4 blocks entries 464c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->max_entries = new_size; 465c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 466c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return true; 467c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 468c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 469c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick ScottMappedFile* BlockFiles::FileForNewBlock(FileType block_type, int block_count) { 470c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott COMPILE_ASSERT(RANKINGS == 1, invalid_fily_type); 471c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott MappedFile* file = block_files_[block_type - 1]; 472c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott BlockFileHeader* header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 473c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 474c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch TimeTicks start = TimeTicks::Now(); 475c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott while (NeedToGrowBlockFile(header, block_count)) { 476c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (kMaxBlocks == header->max_entries) { 477c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott file = NextFile(file); 478c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!file) 479c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return NULL; 480c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 481c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott continue; 482c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 483c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 484c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!GrowBlockFile(file, header)) 485c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return NULL; 486c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott break; 487c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 488c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch HISTOGRAM_TIMES("DiskCache.GetFileForNewBlock", TimeTicks::Now() - start); 489c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return file; 490c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 491c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 492c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick ScottMappedFile* BlockFiles::NextFile(const MappedFile* file) { 493c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott BlockFileHeader* header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 494c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int new_file = header->next_file; 495c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!new_file) { 496c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // RANKINGS is not reported as a type for small entries, but we may be 497c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // extending the rankings block file. 498c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FileType type = Addr::RequiredFileType(header->entry_size); 499c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (header->entry_size == Addr::BlockSizeForFileType(RANKINGS)) 500c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott type = RANKINGS; 501c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 502c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott new_file = CreateNextBlockFile(type); 503c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!new_file) 504c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return NULL; 505c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 506c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FileLock lock(header); 507c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->next_file = new_file; 508c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 509c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 510c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Only the block_file argument is relevant for what we want. 511c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott Addr address(BLOCK_256, 1, new_file, 0); 512c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return GetFile(address); 513c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 514c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 515c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottint BlockFiles::CreateNextBlockFile(FileType block_type) { 516c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch for (int i = kFirstAdditionalBlockFile; i <= kMaxBlockFile; i++) { 517c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (CreateBlockFile(i, block_type, false)) 518c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return i; 519c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 520c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return 0; 521c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 522c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 523c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// We walk the list of files for this particular block type, deleting the ones 524c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// that are empty. 525c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottvoid BlockFiles::RemoveEmptyFile(FileType block_type) { 526c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott MappedFile* file = block_files_[block_type - 1]; 527c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott BlockFileHeader* header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 528c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 529c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott while (header->next_file) { 530c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Only the block_file argument is relevant for what we want. 531c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott Addr address(BLOCK_256, 1, header->next_file, 0); 532c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott MappedFile* next_file = GetFile(address); 533c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!next_file) 534c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return; 535c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 536c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott BlockFileHeader* next_header = 537c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott reinterpret_cast<BlockFileHeader*>(next_file->buffer()); 538c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!next_header->num_entries) { 539c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK_EQ(next_header->entry_size, header->entry_size); 540c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // Delete next_file and remove it from the chain. 541c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int file_index = header->next_file; 542c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->next_file = next_header->next_file; 543c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DCHECK(block_files_.size() >= static_cast<unsigned int>(file_index)); 5443345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick 5453345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick // We get a new handle to the file and release the old one so that the 5463345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick // file gets unmmaped... so we can delete it. 5473345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick FilePath name = Name(file_index); 5483345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick scoped_refptr<File> this_file(new File(false)); 5493345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick this_file->Init(name); 550c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott block_files_[file_index]->Release(); 551c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott block_files_[file_index] = NULL; 552c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 553c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int failure = DeleteCacheFile(name) ? 0 : 1; 554c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott UMA_HISTOGRAM_COUNTS("DiskCache.DeleteFailed2", failure); 555c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (failure) 556c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott LOG(ERROR) << "Failed to delete " << name.value() << " from the cache."; 557c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott continue; 558c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 559c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 560c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header = next_header; 561c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott file = next_file; 562c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 563c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 564c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 565c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottbool BlockFiles::FixBlockFileHeader(MappedFile* file) { 566c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott BlockFileHeader* header = reinterpret_cast<BlockFileHeader*>(file->buffer()); 567c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int file_size = static_cast<int>(file->GetLength()); 568c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (file_size < static_cast<int>(sizeof(*header))) 569c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; // file_size > 2GB is also an error. 570c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 571c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int expected = header->entry_size * header->max_entries + sizeof(*header); 572c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (file_size != expected) { 573c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int max_expected = header->entry_size * kMaxBlocks + sizeof(*header); 574c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (file_size < expected || header->empty[3] || file_size > max_expected) { 575c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott NOTREACHED(); 576c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott LOG(ERROR) << "Unexpected file size"; 577c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 578c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 579c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // We were in the middle of growing the file. 580c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott int num_entries = (file_size - sizeof(*header)) / header->entry_size; 581c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->max_entries = num_entries; 582c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 583c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 584c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott FixAllocationCounters(header); 585c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott header->updating = 0; 586c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return true; 587c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 588c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 5893345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick// We are interested in the total number of blocks used by this file type, and 590c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// the max number of blocks that we can store (reported as the percentage of 591c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// used blocks). In order to find out the number of used blocks, we have to 592c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// substract the empty blocks from the total blocks for each file in the chain. 593c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdochvoid BlockFiles::GetFileStats(int index, int* used_count, int* load) { 594c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch int max_blocks = 0; 595c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch *used_count = 0; 596c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch *load = 0; 597c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch for (;;) { 598c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch if (!block_files_[index] && !OpenBlockFile(index)) 599c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch return; 600c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 601c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch BlockFileHeader* header = 602c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch reinterpret_cast<BlockFileHeader*>(block_files_[index]->buffer()); 603c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 604c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch max_blocks += header->max_entries; 605c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch int used = header->max_entries; 606c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch for (int i = 0; i < 4; i++) { 607c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch used -= header->empty[i] * (i + 1); 608c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch DCHECK_GE(used, 0); 609c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch } 610c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch *used_count += used; 611c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 612c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch if (!header->next_file) 613c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch break; 614c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch index = header->next_file; 615c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch } 616c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch if (max_blocks) 617c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch *load = *used_count * 100 / max_blocks; 618c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch} 619c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 620c407dc5cd9bdc5668497f21b26b09d988ab439deBen MurdochFilePath BlockFiles::Name(int index) { 621c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // The file format allows for 256 files. 622c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch DCHECK(index < 256 || index >= 0); 6233345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick std::string tmp = base::StringPrintf("%s%d", kBlockName, index); 624c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch return path_.AppendASCII(tmp); 625c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch} 626c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 627c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} // namespace disk_cache 628