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 #define DEBUG   0
   9 #include "lvm_int.h"
  10 #define USE_IOCACHE     1
  11
  12 // === PROTOTYPES ===
  13  int    LVM_int_CacheWriteback(void *ID, Uint64 Sector, const void *Buffer);
  14  int    LVM_int_VFSReadEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, void *Dest);
  15  int    LVM_int_VFSWriteEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, const void *Source);
  16
  17 // === CODE ===
  18 // --------------------------------------------------------------------
  19 // Managment / Initialisation
  20 // --------------------------------------------------------------------
  21 int LVM_AddVolumeVFS(const char *Name, int FD)
  22 {
  23         // Assuming 512-byte blocks, not a good idea
  24 //      return LVM_AddVolume(Name, (void*)(Uint)FD, 512, LVM_int_VFSReadEmul, LVM_int_VFSWriteEmul);
  25         return 0;
  26 }
  27
  28 void *LVM_AddVolume(const tLVM_VolType *Type, const char *Name, void *Ptr, size_t BlockSize, size_t BlockCount)
  29 {
  30         tLVM_Vol        dummy_vol;
  31         tLVM_Format     *fmt;
  32
  33         if( BlockCount == 0 || BlockSize == 0 ) {
  34                 Log_Error("LVM", "BlockSize(0x%x)/BlockCount(0x%x) invalid in LVM_AddVolume",
  35                         BlockSize, BlockCount);
  36                 return NULL;
  37         }
  38
  39         dummy_vol.Type = Type;
  40         dummy_vol.Ptr = Ptr;
  41         dummy_vol.BlockCount = BlockCount;
  42         dummy_vol.BlockSize = BlockSize;
  43         dummy_vol.CacheHandle = NULL;
  44
  45         // Read the first block of the volume
  46         void *first_block = malloc(BlockSize);
  47         if( !first_block ) {
  48                 Log_Error("LVM", "LVM_AddVolume - malloc error on %i bytes", BlockSize);
  49                 return NULL;
  50         }
  51         if( Type->Read(Ptr, 0, 1, first_block) != 1 ) {
  52                 Log_Error("LVM", "LVM_AddVolume - Failed to read first sector");
  53                 free(first_block);
  54                 return NULL;
  55         }
  56
  57         // Determine Format
  58         // TODO: Determine format
  59         fmt = &gLVM_MBRType;
  60
  61         // Type->CountSubvolumes
  62         dummy_vol.nSubVolumes = fmt->CountSubvolumes(&dummy_vol, first_block);
  63         Log_Debug("LVM", "Volume %s as format %s gives %i sub-volumes",
  64                 Name, fmt->Name, dummy_vol.nSubVolumes);
  65
  66         // Create real volume descriptor
  67         // TODO: If this needs to be rescanned later, having the subvolume list separate might be an idea
  68         size_t  allocsize = sizeof(tLVM_Vol) + strlen(Name) + 1 + sizeof(tLVM_SubVolume*) * dummy_vol.nSubVolumes;
  69         tLVM_Vol        *real_vol = malloc( allocsize );
  70         if( !real_vol ) {
  71                 Log_Error("LVM", "LVM_AddVolume - malloc error on %i bytes", allocsize);
  72                 free(first_block);
  73                 return NULL;
  74         }
  75         real_vol->Next = NULL;
  76         real_vol->Type = Type;
  77         real_vol->Ptr = Ptr;
  78         real_vol->BlockSize = BlockSize;
  79         real_vol->BlockCount = BlockCount;
  80         real_vol->nSubVolumes = dummy_vol.nSubVolumes;
  81         real_vol->SubVolumes = (void*)( real_vol->Name + strlen(Name) + 1 );
  82         real_vol->BlockSize = BlockSize;
  83         strcpy(real_vol->Name, Name);
  84         memset(real_vol->SubVolumes, 0, sizeof(tLVM_SubVolume*) * real_vol->nSubVolumes);
  85         // - VFS Nodes
  86         memset(&real_vol->DirNode, 0, sizeof(tVFS_Node));
  87         real_vol->DirNode.Type = &gLVM_VolNodeType;
  88         real_vol->DirNode.ImplPtr = real_vol;
  89         real_vol->DirNode.Flags = VFS_FFLAG_DIRECTORY;
  90         real_vol->DirNode.Size = -1;
  91         memset(&real_vol->VolNode, 0, sizeof(tVFS_Node));
  92         real_vol->VolNode.Type = &gLVM_VolNodeType;
  93         real_vol->VolNode.ImplPtr = real_vol;
  94         real_vol->VolNode.Size = BlockCount * BlockSize;
  95
  96         // TODO: Better selection of cache size
  97         // TODO: Allow a volume type to disallow caching
  98         #if USE_IOCACHE
  99         real_vol->CacheHandle = IOCache_Create(LVM_int_CacheWriteback, real_vol, BlockSize, 1024);
 100         #else
 101         real_vol->CacheHandle = NULL;
 102         #endif
 103
 104         // Type->PopulateSubvolumes
 105         fmt->PopulateSubvolumes(real_vol, first_block);
 106         free(first_block);
 107
 108         // Add to volume list
 109         gpLVM_LastVolume->Next = real_vol;
 110         gpLVM_LastVolume = real_vol;
 111
 112         return real_vol;
 113 }
 114
 115 void LVM_int_SetSubvolume_Anon(tLVM_Vol *Volume, int Index, Uint64 FirstBlock, Uint64 BlockCount)
 116 {
 117         tLVM_SubVolume  *sv;
 118          int    namelen;
 119
 120         if( Index < 0 || Index >= Volume->nSubVolumes ) {
 121                 Log_Warning("LVM", "SV ID is out of range (0 < %i < %i)",
 122                         Index, Volume->nSubVolumes);
 123                 return ;
 124         }
 125
 126         if( Volume->SubVolumes[Index] ) {
 127                 Log_Warning("LVM", "Attempt to set SV %i of %p twice", Index, Volume);
 128                 return ;
 129         }
 130
 131         namelen = snprintf(NULL, 0, "%i", Index);
 132
 133         sv = malloc( sizeof(tLVM_SubVolume) + namelen + 1 );
 134         if(!sv) {
 135                 // Oh, f*ck
 136                 return ;
 137         }
 138         Volume->SubVolumes[Index] = sv;
 139
 140         sv->Vol = Volume;
 141         sprintf(sv->Name, "%i", Index);
 142         sv->FirstBlock = FirstBlock;
 143         sv->BlockCount = BlockCount;
 144         memset(&sv->Node, 0, sizeof(tVFS_Node));
 145
 146         sv->Node.ImplPtr = sv;
 147         sv->Node.Type = &gLVM_SubVolNodeType;
 148         sv->Node.Size = BlockCount * Volume->BlockSize;
 149
 150         Log_Log("LVM", "Partition %s/%s - 0x%llx+0x%llx blocks",
 151                 Volume->Name, sv->Name, FirstBlock, BlockCount);
 152 }
 153
 154 // --------------------------------------------------------------------
 155 // IO
 156 // --------------------------------------------------------------------
 157 int LVM_int_CacheWriteback(void *ID, Uint64 Sector, const void *Buffer)
 158 {
 159         tLVM_Vol *Volume = ID;
 160         return Volume->Type->Write(Volume->Ptr, Sector, 1, Buffer);
 161 }
 162
 163 size_t LVM_int_ReadVolume(tLVM_Vol *Volume, Uint64 BlockNum, size_t BlockCount, void *Dest)
 164 {
 165         #if USE_IOCACHE
 166         if( Volume->CacheHandle )
 167         {
 168                  int    done = 0;
 169                 while( done < BlockCount )
 170                 {
 171                         while( done < BlockCount && IOCache_Read(Volume->CacheHandle, BlockNum+done, Dest) == 1 )
 172                                 done ++, Dest = (char*)Dest + Volume->BlockSize;
 173                         size_t first_uncached = done;
 174                         void *uncache_buf = Dest;
 175                         LOG("%i/%i: cached", done, BlockCount);
 176                         while( done < BlockCount && IOCache_Read(Volume->CacheHandle, BlockNum+done, Dest) == 0 )
 177                                 done ++, Dest = (char*)Dest + Volume->BlockSize;
 178                         LOG("%i/%i: uncached", done, BlockCount);
 179                         size_t  count = done-first_uncached;
 180                         if( count ) {
 181                                 Volume->Type->Read(Volume->Ptr, BlockNum+first_uncached, count, uncache_buf);
 182                                 while(count--)
 183                                 {
 184                                         IOCache_Add(Volume->CacheHandle, BlockNum+first_uncached, uncache_buf);
 185                                         first_uncached ++;
 186                                         uncache_buf = (char*)uncache_buf + Volume->BlockSize;
 187                                 }
 188                         }
 189                 }
 190                 return done;
 191         }
 192         else
 193         #endif
 194                 return Volume->Type->Read(Volume->Ptr, BlockNum, BlockCount, Dest);
 195 }
 196
 197 size_t LVM_int_WriteVolume(tLVM_Vol *Volume, Uint64 BlockNum, size_t BlockCount, const void *Src)
 198 {
 199         #if USE_IOCACHE
 200         if( Volume->CacheHandle )
 201         {
 202                 int done = 0;
 203                 while( BlockCount )
 204                 {
 205                         IOCache_Write(Volume->CacheHandle, BlockNum, Src);
 206                         Src = (const char*)Src + Volume->BlockSize;
 207                         BlockNum ++;
 208                         BlockCount --;
 209                         done ++;
 210                 }
 211                 return done;
 212         }
 213         else
 214         #endif
 215                 return Volume->Type->Write(Volume->Ptr, BlockNum, BlockCount, Src);
 216 }
 217
 218 int LVM_int_VFSReadEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, void *Dest)
 219 {
 220         size_t  blocksize;
 221         size_t  rv;
 222
 223         blocksize = 512;        // TODO: Don't assume
 224
 225         rv = VFS_ReadAt( (int)(Uint)Arg, BlockStart * blocksize, BlockCount * blocksize, Dest );
 226         rv /= blocksize;
 227         return rv;
 228 }
 229
 230 int LVM_int_VFSWriteEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, const void *Source)
 231 {
 232         size_t  blocksize;
 233         size_t  rv;
 234
 235         blocksize = 512;        // TODO: Don't assume
 236
 237         rv = VFS_WriteAt( (int)(Uint)Arg, BlockStart * blocksize, BlockCount * blocksize, Source );
 238         rv /= blocksize;
 239         return rv;
 240 }
 241