src/add-ons/kernel/file_systems/ext2/BlockAllocator.h

   1 /*
   2  * Copyright 2001-2010, Haiku Inc. All rights reserved.
   3  * This file may be used under the terms of the MIT License.
   4  *
   5  * Authors:
   6  *              Janito V. Ferreira Filho
   7  */
   8 #ifndef BLOCKALLOCATOR_H
   9 #define BLOCKALLOCATOR_H
  10
  11
  12 #include <lock.h>
  13
  14 #include "ext2.h"
  15 #include "Transaction.h"
  16
  17
  18 class AllocationBlockGroup;
  19 class Inode;
  20 class Volume;
  21
  22
  23 class BlockAllocator {
  24 public:
  25                                                 BlockAllocator(Volume* volume);
  26                                                 ~BlockAllocator();
  27
  28                         status_t        Initialize();
  29
  30                         status_t        AllocateBlocks(Transaction& transaction,
  31                                                         uint32 minimum, uint32 maximum, uint32& blockGroup,
  32                                                         fsblock_t& start, uint32& length);
  33                         status_t        Allocate(Transaction& transaction, Inode* inode,
  34                                                         off_t numBlocks, uint32 minimum, fsblock_t& start,
  35                                                         uint32& length);
  36                         status_t        Free(Transaction& transaction, fsblock_t start,
  37                                                         uint32 length);
  38
  39                         uint32          FreeBlocks();
  40
  41 protected:
  42         static  status_t        _Initialize(BlockAllocator* allocator);
  43
  44
  45                         Volume*         fVolume;
  46                         mutex           fLock;
  47
  48                         AllocationBlockGroup* fGroups;
  49                         uint32          fBlocksPerGroup;
  50                         fsblock_t       fNumBlocks;
  51                         uint32          fNumGroups;
  52                         fsblock_t       fFirstBlock;
  53 };
  54
  55 #endif  // BLOCKALLOCATOR_H