src/fs/rock/RockSwapDir.h

   1 #ifndef SQUID_FS_ROCK_SWAP_DIR_H
   2 #define SQUID_FS_ROCK_SWAP_DIR_H
   3
   4 #include "SwapDir.h"
   5 #include "DiskIO/DiskFile.h"
   6 #include "DiskIO/IORequestor.h"
   7 #include "fs/rock/RockDbCell.h"
   8 #include "fs/rock/RockForward.h"
   9 #include "ipc/StoreMap.h"
  10 #include "ipc/mem/Page.h"
  11 #include "ipc/mem/PageStack.h"
  12
  13 class DiskIOStrategy;
  14 class ReadRequest;
  15 class WriteRequest;
  16
  17 namespace Rock
  18 {
  19
  20 /// \ingroup Rock
  21 class SwapDir: public ::SwapDir, public IORequestor, public Ipc::StoreMapCleaner
  22 {
  23 public:
  24     typedef RefCount<SwapDir> Pointer;
  25     typedef Ipc::StoreMap DirMap;
  26
  27     SwapDir();
  28     virtual ~SwapDir();
  29
  30     /* public ::SwapDir API */
  31     virtual void reconfigure();
  32     virtual StoreSearch *search(String const url, HttpRequest *);
  33     virtual StoreEntry *get(const cache_key *key);
  34     virtual void get(String const, STOREGETCLIENT, void * cbdata);
  35     virtual void disconnect(StoreEntry &e);
  36     virtual uint64_t currentSize() const;
  37     virtual uint64_t currentCount() const;
  38     virtual bool doReportStat() const;
  39     virtual void swappedOut(const StoreEntry &e);
  40     virtual void create();
  41     virtual void parse(int index, char *path);
  42
  43     // temporary path to the shared memory map of first slots of cached entries
  44     const char *inodeMapPath() const;
  45     // temporary path to the shared memory stack of free slots
  46     const char *freeSlotsPath() const;
  47
  48     int64_t entryLimitHigh() const { return SwapFilenMax; } ///< Core limit
  49     int64_t entryLimitAllowed() const;
  50
  51     /// removes a slot from a list of free slots or returns false
  52     bool useFreeSlot(Ipc::Mem::PageId &pageId);
  53     /// whether the given slot ID may point to a slot in this db
  54     bool validSlotId(const SlotId slotId) const;
  55     /// purges one or more entries to make full() false and free some slots
  56     void purgeSome();
  57
  58     int64_t diskOffset(Ipc::Mem::PageId &pageId) const;
  59     int64_t diskOffset(int filen) const;
  60     void writeError(const sfileno fileno);
  61
  62     /* StoreMapCleaner API */
  63     virtual void noteFreeMapSlice(const sfileno fileno);
  64
  65     uint64_t slotSize; ///< all db slots are of this size
  66
  67 protected:
  68     /* protected ::SwapDir API */
  69     virtual bool needsDiskStrand() const;
  70     virtual void init();
  71     virtual ConfigOption *getOptionTree() const;
  72     virtual bool allowOptionReconfigure(const char *const option) const;
  73     virtual bool canStore(const StoreEntry &e, int64_t diskSpaceNeeded, int &load) const;
  74     virtual StoreIOState::Pointer createStoreIO(StoreEntry &, StoreIOState::STFNCB *, StoreIOState::STIOCB *, void *);
  75     virtual StoreIOState::Pointer openStoreIO(StoreEntry &, StoreIOState::STFNCB *, StoreIOState::STIOCB *, void *);
  76     virtual void maintain();
  77     virtual void diskFull();
  78     virtual void reference(StoreEntry &e);
  79     virtual bool dereference(StoreEntry &e, bool);
  80     virtual bool unlinkdUseful() const;
  81     virtual void unlink(StoreEntry &e);
  82     virtual void statfs(StoreEntry &e) const;
  83
  84     /* IORequestor API */
  85     virtual void ioCompletedNotification();
  86     virtual void closeCompleted();
  87     virtual void readCompleted(const char *buf, int len, int errflag, RefCount< ::ReadRequest>);
  88     virtual void writeCompleted(int errflag, size_t len, RefCount< ::WriteRequest>);
  89
  90     void parseSize(const bool reconfiguring); ///< parses anonymous cache_dir size option
  91     void validateOptions(); ///< warns of configuration problems; may quit
  92     bool parseTimeOption(char const *option, const char *value, int reconfiguring);
  93     void dumpTimeOption(StoreEntry * e) const;
  94     bool parseRateOption(char const *option, const char *value, int reconfiguring);
  95     void dumpRateOption(StoreEntry * e) const;
  96     bool parseSizeOption(char const *option, const char *value, int reconfiguring);
  97     void dumpSizeOption(StoreEntry * e) const;
  98
  99     void rebuild(); ///< starts loading and validating stored entry metadata
 100
 101     bool full() const; ///< no more entries can be stored without purging
 102     void trackReferences(StoreEntry &e); ///< add to replacement policy scope
 103     void ignoreReferences(StoreEntry &e); ///< delete from repl policy scope
 104
 105     int64_t diskOffsetLimit() const;
 106     int entryLimit() const { return map->entryLimit(); }
 107     int entryMaxPayloadSize() const;
 108     int entriesNeeded(const int64_t objSize) const;
 109
 110     friend class Rebuild;
 111     friend class IoState;
 112     const char *filePath; ///< location of cache storage file inside path/
 113     DirMap *map; ///< entry key/sfileno to MaxExtras/inode mapping
 114
 115 private:
 116     void createError(const char *const msg);
 117
 118     DiskIOStrategy *io;
 119     RefCount<DiskFile> theFile; ///< cache storage for this cache_dir
 120     Ipc::Mem::Pointer<Ipc::Mem::PageStack> freeSlots; ///< all unused slots
 121     Ipc::Mem::PageId *waitingForPage; ///< one-page cache for a "hot" free slot
 122
 123     /* configurable options */
 124     DiskFile::Config fileConfig; ///< file-level configuration options
 125
 126     static const int64_t HeaderSize; ///< on-disk db header size
 127 };
 128
 129 /// initializes shared memory segments used by Rock::SwapDir
 130 class SwapDirRr: public Ipc::Mem::RegisteredRunner
 131 {
 132 public:
 133     /* ::RegisteredRunner API */
 134     virtual ~SwapDirRr();
 135
 136 protected:
 137     /* Ipc::Mem::RegisteredRunner API */
 138     virtual void create(const RunnerRegistry &);
 139
 140 private:
 141     Vector<SwapDir::DirMap::Owner *> mapOwners;
 142     Vector< Ipc::Mem::Owner<Ipc::Mem::PageStack> *> freeSlotsOwners;
 143 };
 144
 145 } // namespace Rock
 146
 147 #endif /* SQUID_FS_ROCK_SWAP_DIR_H */