KernelLand/Modules/Storage/LVM/volumes.c

   1 /*
   2  * Acess2 Logical Volume Manager
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * volumes.c
   6  * - Volume management
   7  */
   8 #include "lvm_int.h"
   9
  10 // === PROTOTYPES ===
  11  int    LVM_int_VFSReadEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, void *Dest);
  12  int    LVM_int_VFSWriteEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, const void *Source);
  13
  14 // === CODE ===
  15 // --------------------------------------------------------------------
  16 // Managment / Initialisation
  17 // --------------------------------------------------------------------
  18 int LVM_AddVolumeVFS(const char *Name, int FD)
  19 {
  20         // Assuming 512-byte blocks, not a good idea
  21         return LVM_AddVolume(Name, (void*)(Uint)FD, 512, LVM_int_VFSReadEmul, LVM_int_VFSWriteEmul);
  22 }
  23
  24 int LVM_AddVolume(const char *Name, void *Ptr, size_t BlockSize, tLVM_ReadFcn Read, tLVM_WriteFcn Write)
  25 {
  26         tLVM_Vol        dummy_vol;
  27         tLVM_Vol        *real_vol;
  28         tLVM_Format     *type;
  29         void    *first_block;
  30
  31         dummy_vol.Ptr = Ptr;
  32         dummy_vol.Read = Read;
  33         dummy_vol.Write = Write;
  34         dummy_vol.BlockSize = BlockSize;
  35
  36         // Read the first block of the volume
  37         first_block = malloc(BlockSize);
  38         Read(Ptr, 0, 1, first_block);
  39
  40         // Determine Type
  41         // TODO: Determine type
  42         type = &gLVM_MBRType;
  43
  44         // Type->CountSubvolumes
  45         dummy_vol.nSubVolumes = type->CountSubvolumes(&dummy_vol, first_block);
  46
  47         // Create real volume descriptor
  48         // TODO: If this needs to be rescanned later, having the subvolume list separate might be an idea
  49         real_vol = malloc( sizeof(tLVM_Vol) + strlen(Name) + 1 + sizeof(tLVM_SubVolume*) * dummy_vol.nSubVolumes );
  50         real_vol->Ptr = Ptr;
  51         real_vol->Read = Read;
  52         real_vol->Write = Write;
  53         real_vol->BlockSize = BlockSize;
  54         real_vol->nSubVolumes = dummy_vol.nSubVolumes;
  55         real_vol->SubVolumes = (void*)( real_vol->Name + strlen(Name) + 1 );
  56         strcpy(real_vol->Name, Name);
  57         memset(real_vol->SubVolumes, 0, sizeof(tLVM_SubVolume*) * real_vol->nSubVolumes);
  58         // - VFS Nodes
  59         memset(&real_vol->DirNode, 0, sizeof(tVFS_Node));
  60         real_vol->DirNode.Type = &gLVM_VolNodeType;
  61         real_vol->DirNode.ImplPtr = real_vol;
  62         real_vol->DirNode.Flags = VFS_FFLAG_DIRECTORY;
  63         memset(&real_vol->VolNode, 0, sizeof(tVFS_Node));
  64         real_vol->VolNode.Type = &gLVM_VolNodeType;
  65         real_vol->VolNode.ImplPtr = real_vol;
  66         real_vol->VolNode.Flags = VFS_FFLAG_DIRECTORY;
  67
  68         // Type->PopulateSubvolumes
  69         type->PopulateSubvolumes(real_vol, first_block);
  70         free(first_block);
  71
  72         // Add to volume list
  73         gpLVM_LastVolume->Next = real_vol;
  74         gpLVM_LastVolume = real_vol;
  75
  76         return 0;
  77 }
  78
  79 void LVM_int_SetSubvolume_Anon(tLVM_Vol *Volume, int Index, Uint64 FirstBlock, Uint64 BlockCount)
  80 {
  81         tLVM_SubVolume  *sv;
  82          int    namelen;
  83
  84         if( Index < 0 || Index >= Volume->nSubVolumes ) {
  85                 Log_Warning("LVM", "SV ID is out of range (0 < %i < %i)",
  86                         Index, Volume->nSubVolumes);
  87                 return ;
  88         }
  89
  90         if( Volume->SubVolumes[Index] ) {
  91                 Log_Warning("LVM", "Attempt to set SV %i of %p twice", Index, Volume);
  92                 return ;
  93         }
  94
  95         namelen = snprintf(NULL, 0, "%i", Index);
  96
  97         sv = malloc( sizeof(tLVM_SubVolume) + namelen + 1 );
  98         if(!sv) {
  99                 // Oh, f*ck
 100                 return ;
 101         }
 102         Volume->SubVolumes[Index] = sv;
 103
 104         sv->Vol = Volume;
 105         sprintf(sv->Name, "%i", Index);
 106         sv->FirstBlock = FirstBlock;
 107         sv->BlockCount = BlockCount;
 108         memset(&sv->Node, 0, sizeof(tVFS_Node));
 109
 110         sv->Node.ImplPtr = sv;
 111         sv->Node.Type = &gLVM_SubVolNodeType;
 112 }
 113
 114 // --------------------------------------------------------------------
 115 // IO
 116 // --------------------------------------------------------------------
 117 size_t LVM_int_ReadVolume(tLVM_Vol *Volume, Uint64 BlockNum, size_t BlockCount, void *Dest)
 118 {
 119         return Volume->Read(Volume->Ptr, BlockNum, BlockCount, Dest);
 120 }
 121
 122 size_t LVM_int_WriteVolume(tLVM_Vol *Volume, Uint64 BlockNum, size_t BlockCount, const void *Src)
 123 {
 124         return Volume->Write(Volume->Ptr, BlockNum, BlockCount, Src);
 125 }
 126
 127 int LVM_int_VFSReadEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, void *Dest)
 128 {
 129         size_t  blocksize;
 130         size_t  rv;
 131
 132         blocksize = 512;        // TODO: Don't assume
 133
 134         rv = VFS_ReadAt( (int)(Uint)Arg, BlockStart * blocksize, BlockCount * blocksize, Dest );
 135         rv /= blocksize;
 136         return rv;
 137 }
 138
 139 int LVM_int_VFSWriteEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, const void *Source)
 140 {
 141         size_t  blocksize;
 142         size_t  rv;
 143
 144         blocksize = 512;        // TODO: Don't assume
 145
 146         rv = VFS_WriteAt( (int)(Uint)Arg, BlockStart * blocksize, BlockCount * blocksize, Source );
 147         rv /= blocksize;
 148         return rv;
 149 }
 150