src/system/kernel/device_manager/IOSchedulerRoster.h

   1 /*
   2  * Copyright 2009-2010, Ingo Weinhold, ingo_weinhold@gmx.de.
   3  * Distributed under the terms of the MIT License.
   4  */
   5 #ifndef IO_SCHEDULER_ROSTER_H
   6 #define IO_SCHEDULER_ROSTER_H
   7
   8
   9 #include <Notifications.h>
  10
  11 #include "IOScheduler.h"
  12
  13
  14 // I/O scheduler notifications
  15 #define IO_SCHEDULER_MONITOR                    '_io_'
  16 #define IO_SCHEDULER_ADDED                              0x01
  17 #define IO_SCHEDULER_REMOVED                    0x02
  18 #define IO_SCHEDULER_REQUEST_SCHEDULED  0x04
  19 #define IO_SCHEDULER_REQUEST_FINISHED   0x08
  20 #define IO_SCHEDULER_OPERATION_STARTED  0x10
  21 #define IO_SCHEDULER_OPERATION_FINISHED 0x20
  22
  23
  24
  25 typedef DoublyLinkedList<IOScheduler> IOSchedulerList;
  26
  27
  28 class IOSchedulerRoster {
  29 public:
  30         static  void                            Init();
  31         static  IOSchedulerRoster*      Default()       { return &sDefaultInstance; }
  32
  33                         bool                            Lock()  { return mutex_lock(&fLock) == B_OK; }
  34                         void                            Unlock()        { mutex_unlock(&fLock); }
  35
  36                         const IOSchedulerList& SchedulerList() const
  37                                                                         { return fSchedulers; }
  38                                                                         // caller must keep the roster locked,
  39                                                                         // while accessing the list
  40
  41                         void                            AddScheduler(IOScheduler* scheduler);
  42                         void                            RemoveScheduler(IOScheduler* scheduler);
  43
  44                         void                            Notify(uint32 eventCode,
  45                                                                         const IOScheduler* scheduler,
  46                                                                         IORequest* request = NULL,
  47                                                                         IOOperation* operation = NULL);
  48
  49                         int32                           NextID();
  50
  51 private:
  52                                                                 IOSchedulerRoster();
  53                                                                 ~IOSchedulerRoster();
  54
  55 private:
  56                         mutex                           fLock;
  57                         int32                           fNextID;
  58                         IOSchedulerList         fSchedulers;
  59                         DefaultNotificationService fNotificationService;
  60                         char                            fEventBuffer[256];
  61
  62         static  IOSchedulerRoster       sDefaultInstance;
  63 };
  64
  65
  66 #endif  // IO_SCHEDULER_ROSTER_H