src/system/kernel/device_manager/IOScheduler.h

   1 /*
   2  * Copyright 2010, Ingo Weinhold, ingo_weinhold@gmx.de.
   3  * Distributed under the terms of the MIT License.
   4  */
   5 #ifndef IO_SCHEDULER_H
   6 #define IO_SCHEDULER_H
   7
   8
   9 #include <KernelExport.h>
  10
  11 #include <util/DoublyLinkedList.h>
  12
  13 #include "IOCallback.h"
  14 #include "IORequest.h"
  15
  16
  17 struct IORequestOwner : DoublyLinkedListLinkImpl<IORequestOwner> {
  18         team_id                 team;
  19         thread_id               thread;
  20         int32                   priority;
  21         IORequestList   requests;
  22         IORequestList   completed_requests;
  23         IOOperationList operations;
  24         IORequestOwner* hash_link;
  25
  26                         bool                            IsActive() const
  27                                                                         { return !requests.IsEmpty()
  28                                                                                 || !completed_requests.IsEmpty()
  29                                                                                 || !operations.IsEmpty(); }
  30
  31                         void                            Dump() const;
  32 };
  33
  34
  35 class IOScheduler : public DoublyLinkedListLinkImpl<IOScheduler> {
  36 public:
  37                                                                 IOScheduler(DMAResource* resource);
  38         virtual                                         ~IOScheduler();
  39
  40         virtual status_t                        Init(const char* name);
  41
  42                         const char*                     Name() const    { return fName; }
  43                         int32                           ID() const              { return fID; }
  44
  45         virtual void                            SetCallback(IOCallback& callback);
  46         virtual void                            SetCallback(io_callback callback, void* data);
  47
  48         virtual void                            SetDeviceCapacity(off_t deviceCapacity);
  49         virtual void                            MediaChanged();
  50
  51         virtual status_t                        ScheduleRequest(IORequest* request) = 0;
  52
  53         virtual void                            AbortRequest(IORequest* request,
  54                                                                         status_t status = B_CANCELED) = 0;
  55         virtual void                            OperationCompleted(IOOperation* operation,
  56                                                                         status_t status,
  57                                                                         generic_size_t transferredBytes) = 0;
  58                                                                         // called by the driver when the operation
  59                                                                         // has been completed successfully or failed
  60                                                                         // for some reason
  61
  62         virtual void                            Dump() const = 0;
  63
  64 protected:
  65                         DMAResource*            fDMAResource;
  66                         char*                           fName;
  67                         int32                           fID;
  68                         io_callback                     fIOCallback;
  69                         void*                           fIOCallbackData;
  70                         bool                            fSchedulerRegistered;
  71 };
  72
  73
  74 #endif  // IO_SCHEDULER_H