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
  64         // Create real volume descriptor
  65         // TODO: If this needs to be rescanned later, having the subvolume list separate might be an idea
  66         size_t  allocsize = sizeof(tLVM_Vol) + strlen(Name) + 1 + sizeof(tLVM_SubVolume*) * dummy_vol.nSubVolumes;
  67         tLVM_Vol        *real_vol = malloc( allocsize );
  68         if( !real_vol ) {
  69                 Log_Error("LVM", "LVM_AddVolume - malloc error on %i bytes", allocsize);
  70                 free(first_block);
  71                 return NULL;
  72         }
  73         real_vol->Next = NULL;
  74         real_vol->Type = Type;
  75         real_vol->Ptr = Ptr;
  76         real_vol->BlockSize = BlockSize;
  77         real_vol->BlockCount = BlockCount;
  78         real_vol->nSubVolumes = dummy_vol.nSubVolumes;
  79         real_vol->SubVolumes = (void*)( real_vol->Name + strlen(Name) + 1 );
  80         real_vol->BlockSize = BlockSize;
  81         strcpy(real_vol->Name, Name);
  82         memset(real_vol->SubVolumes, 0, sizeof(tLVM_SubVolume*) * real_vol->nSubVolumes);
  83         // - VFS Nodes
  84         memset(&real_vol->DirNode, 0, sizeof(tVFS_Node));
  85         real_vol->DirNode.Type = &gLVM_VolNodeType;
  86         real_vol->DirNode.ImplPtr = real_vol;
  87         real_vol->DirNode.Flags = VFS_FFLAG_DIRECTORY;
  88         real_vol->DirNode.Size = -1;
  89         memset(&real_vol->VolNode, 0, sizeof(tVFS_Node));
  90         real_vol->VolNode.Type = &gLVM_VolNodeType;
  91         real_vol->VolNode.ImplPtr = real_vol;
  92         real_vol->VolNode.Size = BlockCount * BlockSize;
  93
  94         // TODO: Better selection of cache size
  95         // TODO: Allow a volume type to disallow caching
  96         #if USE_IOCACHE
  97         real_vol->CacheHandle = IOCache_Create(LVM_int_CacheWriteback, real_vol, BlockSize, 1024);
  98         #else
  99         real_vol->CacheHandle = NULL;
 100         #endif
 101
 102         // Type->PopulateSubvolumes
 103         fmt->PopulateSubvolumes(real_vol, first_block);
 104         free(first_block);
 105
 106         // Add to volume list
 107         gpLVM_LastVolume->Next = real_vol;
 108         gpLVM_LastVolume = real_vol;
 109
 110         return real_vol;
 111 }
 112
 113 void LVM_int_SetSubvolume_Anon(tLVM_Vol *Volume, int Index, Uint64 FirstBlock, Uint64 BlockCount)
 114 {
 115         tLVM_SubVolume  *sv;
 116          int    namelen;
 117
 118         if( Index < 0 || Index >= Volume->nSubVolumes ) {
 119                 Log_Warning("LVM", "SV ID is out of range (0 < %i < %i)",
 120                         Index, Volume->nSubVolumes);
 121                 return ;
 122         }
 123
 124         if( Volume->SubVolumes[Index] ) {
 125                 Log_Warning("LVM", "Attempt to set SV %i of %p twice", Index, Volume);
 126                 return ;
 127         }
 128
 129         namelen = snprintf(NULL, 0, "%i", Index);
 130
 131         sv = malloc( sizeof(tLVM_SubVolume) + namelen + 1 );
 132         if(!sv) {
 133                 // Oh, f*ck
 134                 return ;
 135         }
 136         Volume->SubVolumes[Index] = sv;
 137
 138         sv->Vol = Volume;
 139         sprintf(sv->Name, "%i", Index);
 140         sv->FirstBlock = FirstBlock;
 141         sv->BlockCount = BlockCount;
 142         memset(&sv->Node, 0, sizeof(tVFS_Node));
 143
 144         sv->Node.ImplPtr = sv;
 145         sv->Node.Type = &gLVM_SubVolNodeType;
 146         sv->Node.Size = BlockCount * Volume->BlockSize;
 147
 148         Log_Log("LVM", "Partition %s/%s - 0x%llx+0x%llx blocks",
 149                 Volume->Name, sv->Name, FirstBlock, BlockCount);
 150 }
 151
 152 // --------------------------------------------------------------------
 153 // IO
 154 // --------------------------------------------------------------------
 155 int LVM_int_CacheWriteback(void *ID, Uint64 Sector, const void *Buffer)
 156 {
 157         tLVM_Vol *Volume = ID;
 158         return Volume->Type->Write(Volume->Ptr, Sector, 1, Buffer);
 159 }
 160
 161 size_t LVM_int_ReadVolume(tLVM_Vol *Volume, Uint64 BlockNum, size_t BlockCount, void *Dest)
 162 {
 163         #if USE_IOCACHE
 164         if( Volume->CacheHandle )
 165         {
 166                  int    done = 0;
 167                 while( done < BlockCount )
 168                 {
 169                         while( done < BlockCount && IOCache_Read(Volume->CacheHandle, BlockNum+done, Dest) == 1 )
 170                                 done ++, Dest = (char*)Dest + Volume->BlockSize;
 171                         size_t first_uncached = done;
 172                         void *uncache_buf = Dest;
 173                         LOG("%i/%i: cached", done, BlockCount);
 174                         while( done < BlockCount && IOCache_Read(Volume->CacheHandle, BlockNum+done, Dest) == 0 )
 175                                 done ++, Dest = (char*)Dest + Volume->BlockSize;
 176                         LOG("%i/%i: uncached", done, BlockCount);
 177                         size_t  count = done-first_uncached;
 178                         if( count ) {
 179                                 Volume->Type->Read(Volume->Ptr, BlockNum+first_uncached, count, uncache_buf);
 180                                 while(count--)
 181                                 {
 182                                         IOCache_Add(Volume->CacheHandle, BlockNum+first_uncached, uncache_buf);
 183                                         first_uncached ++;
 184                                         uncache_buf = (char*)uncache_buf + Volume->BlockSize;
 185                                 }
 186                         }
 187                 }
 188                 return done;
 189         }
 190         else
 191         #endif
 192                 return Volume->Type->Read(Volume->Ptr, BlockNum, BlockCount, Dest);
 193 }
 194
 195 size_t LVM_int_WriteVolume(tLVM_Vol *Volume, Uint64 BlockNum, size_t BlockCount, const void *Src)
 196 {
 197         #if USE_IOCACHE
 198         if( Volume->CacheHandle )
 199         {
 200                 int done = 0;
 201                 while( BlockCount )
 202                 {
 203                         IOCache_Write(Volume->CacheHandle, BlockNum, Src);
 204                         Src = (const char*)Src + Volume->BlockSize;
 205                         BlockNum ++;
 206                         BlockCount --;
 207                         done ++;
 208                 }
 209                 return done;
 210         }
 211         else
 212         #endif
 213                 return Volume->Type->Write(Volume->Ptr, BlockNum, BlockCount, Src);
 214 }
 215
 216 int LVM_int_VFSReadEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, void *Dest)
 217 {
 218         size_t  blocksize;
 219         size_t  rv;
 220
 221         blocksize = 512;        // TODO: Don't assume
 222
 223         rv = VFS_ReadAt( (int)(Uint)Arg, BlockStart * blocksize, BlockCount * blocksize, Dest );
 224         rv /= blocksize;
 225         return rv;
 226 }
 227
 228 int LVM_int_VFSWriteEmul(void *Arg, Uint64 BlockStart, size_t BlockCount, const void *Source)
 229 {
 230         size_t  blocksize;
 231         size_t  rv;
 232
 233         blocksize = 512;        // TODO: Don't assume
 234
 235         rv = VFS_WriteAt( (int)(Uint)Arg, BlockStart * blocksize, BlockCount * blocksize, Source );
 236         rv /= blocksize;
 237         return rv;
 238 }
 239