src/fs/rock/RockSwapDir.h

   1 #ifndef SQUID_FS_ROCK_SWAP_DIR_H
   2 #define SQUID_FS_ROCK_SWAP_DIR_H
   3
   4 #include "DiskIO/DiskFile.h"
   5 #include "DiskIO/IORequestor.h"
   6 #include "fs/rock/RockDbCell.h"
   7 #include "fs/rock/RockForward.h"
   8 #include "ipc/mem/Page.h"
   9 #include "ipc/mem/PageStack.h"
  10 #include "ipc/StoreMap.h"
  11 #include "SwapDir.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 markForUnlink(StoreEntry &e);
  36     virtual void disconnect(StoreEntry &e);
  37     virtual uint64_t currentSize() const;
  38     virtual uint64_t currentCount() const;
  39     virtual bool doReportStat() const;
  40     virtual void swappedOut(const StoreEntry &e);
  41     virtual void create();
  42     virtual void parse(int index, char *path);
  43
  44     // temporary path to the shared memory map of first slots of cached entries
  45     SBuf inodeMapPath() const;
  46     // temporary path to the shared memory stack of free slots
  47     const char *freeSlotsPath() const;
  48
  49     int64_t entryLimitAbsolute() const { return SwapFilenMax+1; } ///< Core limit
  50     int64_t entryLimitActual() const; ///< max number of possible entries in db
  51     int64_t slotLimitAbsolute() const; ///< Rock store implementation limit
  52     int64_t slotLimitActual() const; ///< total number of slots in this db
  53
  54     /// removes a slot from a list of free slots or returns false
  55     bool useFreeSlot(Ipc::Mem::PageId &pageId);
  56     /// whether the given slot ID may point to a slot in this db
  57     bool validSlotId(const SlotId slotId) const;
  58     /// purges one or more entries to make full() false and free some slots
  59     void purgeSome();
  60
  61     int64_t diskOffset(Ipc::Mem::PageId &pageId) const;
  62     int64_t diskOffset(int filen) const;
  63     void writeError(StoreEntry &e);
  64
  65     /* StoreMapCleaner API */
  66     virtual void noteFreeMapSlice(const Ipc::StoreMapSliceId fileno);
  67
  68     uint64_t slotSize; ///< all db slots are of this size
  69
  70 protected:
  71     /* Store API */
  72     virtual bool anchorCollapsed(StoreEntry &collapsed, bool &inSync);
  73     virtual bool updateCollapsed(StoreEntry &collapsed);
  74
  75     /* protected ::SwapDir API */
  76     virtual bool needsDiskStrand() const;
  77     virtual void init();
  78     virtual ConfigOption *getOptionTree() const;
  79     virtual bool allowOptionReconfigure(const char *const option) const;
  80     virtual bool canStore(const StoreEntry &e, int64_t diskSpaceNeeded, int &load) const;
  81     virtual StoreIOState::Pointer createStoreIO(StoreEntry &, StoreIOState::STFNCB *, StoreIOState::STIOCB *, void *);
  82     virtual StoreIOState::Pointer openStoreIO(StoreEntry &, StoreIOState::STFNCB *, StoreIOState::STIOCB *, void *);
  83     virtual void maintain();
  84     virtual void diskFull();
  85     virtual void reference(StoreEntry &e);
  86     virtual bool dereference(StoreEntry &e, bool);
  87     virtual bool unlinkdUseful() const;
  88     virtual void unlink(StoreEntry &e);
  89     virtual void statfs(StoreEntry &e) const;
  90
  91     /* IORequestor API */
  92     virtual void ioCompletedNotification();
  93     virtual void closeCompleted();
  94     virtual void readCompleted(const char *buf, int len, int errflag, RefCount< ::ReadRequest>);
  95     virtual void writeCompleted(int errflag, size_t len, RefCount< ::WriteRequest>);
  96
  97     void parseSize(const bool reconfiguring); ///< parses anonymous cache_dir size option
  98     void validateOptions(); ///< warns of configuration problems; may quit
  99     bool parseTimeOption(char const *option, const char *value, int reconfiguring);
 100     void dumpTimeOption(StoreEntry * e) const;
 101     bool parseRateOption(char const *option, const char *value, int reconfiguring);
 102     void dumpRateOption(StoreEntry * e) const;
 103     bool parseSizeOption(char const *option, const char *value, int reconfiguring);
 104     void dumpSizeOption(StoreEntry * e) const;
 105
 106     void rebuild(); ///< starts loading and validating stored entry metadata
 107
 108     bool full() const; ///< no more entries can be stored without purging
 109     void trackReferences(StoreEntry &e); ///< add to replacement policy scope
 110     void ignoreReferences(StoreEntry &e); ///< delete from repl policy scope
 111
 112     int64_t diskOffsetLimit() const;
 113
 114     void anchorEntry(StoreEntry &e, const sfileno filen, const Ipc::StoreMapAnchor &anchor);
 115     bool updateCollapsedWith(StoreEntry &collapsed, const Ipc::StoreMapAnchor &anchor);
 116
 117     friend class Rebuild;
 118     friend class IoState;
 119     const char *filePath; ///< location of cache storage file inside path/
 120     DirMap *map; ///< entry key/sfileno to MaxExtras/inode mapping
 121
 122 private:
 123     void createError(const char *const msg);
 124
 125     DiskIOStrategy *io;
 126     RefCount<DiskFile> theFile; ///< cache storage for this cache_dir
 127     Ipc::Mem::Pointer<Ipc::Mem::PageStack> freeSlots; ///< all unused slots
 128     Ipc::Mem::PageId *waitingForPage; ///< one-page cache for a "hot" free slot
 129
 130     /* configurable options */
 131     DiskFile::Config fileConfig; ///< file-level configuration options
 132
 133     static const int64_t HeaderSize; ///< on-disk db header size
 134 };
 135
 136 /// initializes shared memory segments used by Rock::SwapDir
 137 class SwapDirRr: public Ipc::Mem::RegisteredRunner
 138 {
 139 public:
 140     /* ::RegisteredRunner API */
 141     virtual ~SwapDirRr();
 142
 143 protected:
 144     /* Ipc::Mem::RegisteredRunner API */
 145     virtual void create();
 146
 147 private:
 148     Vector<SwapDir::DirMap::Owner *> mapOwners;
 149     Vector< Ipc::Mem::Owner<Ipc::Mem::PageStack> *> freeSlotsOwners;
 150 };
 151
 152 } // namespace Rock
 153
 154 #endif /* SQUID_FS_ROCK_SWAP_DIR_H */