src/add-ons/kernel/file_systems/btrfs/Chunk.cpp

   1 /*
   2  * Copyright 2011, Haiku Inc. All rights reserved.
   3  * This file may be used under the terms of the MIT License.
   4  *
   5  * Authors:
   6  *              Jérôme Duval
   7  */
   8
   9
  10 #include "Chunk.h"
  11
  12
  13 //#define TRACE_BTRFS
  14 #ifdef TRACE_BTRFS
  15 #       define TRACE(x...) dprintf("\33[34mbtrfs:\33[0m " x)
  16 #else
  17 #       define TRACE(x...) ;
  18 #endif
  19 #       define FATAL(x...) dprintf("\33[34mbtrfs:\33[0m " x)
  20
  21
  22 Chunk::Chunk(btrfs_chunk* chunk, fsblock_t offset)
  23         :
  24         fChunk(NULL),
  25         fInitStatus(B_OK)
  26 {
  27         fChunkOffset = offset;
  28         fChunk = (btrfs_chunk*)malloc(sizeof(btrfs_chunk)
  29                 + chunk->StripeCount() * sizeof(btrfs_stripe));
  30         if (fChunk == NULL) {
  31                 fInitStatus = B_NO_MEMORY;
  32                 return;
  33         }
  34
  35         memcpy(fChunk, chunk, sizeof(btrfs_chunk)
  36                 + chunk->StripeCount() * sizeof(btrfs_stripe));
  37
  38         TRACE("chunk[0] length %" B_PRIu64 " owner %" B_PRIu64 " stripe_length %"
  39                 B_PRIu64 " type %" B_PRIu64 " stripe_count %u sub_stripes %u "
  40                 "sector_size %" B_PRIu32 "\n", chunk->Length(), chunk->Owner(),
  41                 chunk->StripeLength(), chunk->Type(), chunk->StripeCount(),
  42                 chunk->SubStripes(), chunk->SectorSize());
  43         for (int32 i = 0; i < chunk->StripeCount(); i++) {
  44                 TRACE("chunk.stripe[%" B_PRId32 "].physical %" B_PRId64 " deviceid %"
  45                         B_PRId64 "\n", i, chunk->stripes[i].Offset(),
  46                         chunk->stripes[i].DeviceID());
  47         }
  48 }
  49
  50
  51 Chunk::~Chunk()
  52 {
  53         free(fChunk);
  54 }
  55
  56
  57 uint32
  58 Chunk::Size() const
  59 {
  60         return sizeof(btrfs_chunk)
  61                 + fChunk->StripeCount() * sizeof(btrfs_stripe);
  62 }
  63
  64
  65 status_t
  66 Chunk::FindBlock(off_t logical, off_t& physical)
  67 {
  68         if (fChunk == NULL)
  69                 return B_NO_INIT;
  70
  71         if (logical < (off_t)fChunkOffset
  72                 || logical > (off_t)(fChunkOffset + fChunk->Length()))
  73                 return B_BAD_VALUE;
  74
  75         // only one stripe
  76         physical = logical + fChunk->stripes[0].Offset() - fChunkOffset;
  77         return B_OK;
  78 }
  79