+++ /dev/null
-/*\r
- * Acess OS\r
- * Ext2 Driver Version 1\r
- */\r
-/**\r
- * \file fs/ext2.c\r
- * \brief Second Extended Filesystem Driver\r
- * \todo Implement file full write support\r
- */\r
-#define DEBUG 1\r
-#define VERBOSE 0\r
-#include <common.h>\r
-#include <vfs.h>\r
-#include <modules.h>\r
-#include "fs_ext2.h"\r
-\r
-#define EXT2_UPDATE_WRITEBACK 1\r
-\r
-// === STRUCTURES ===\r
-typedef struct {\r
- int FD;\r
- int CacheID;\r
- tVFS_Node RootNode;\r
- \r
- tExt2_SuperBlock SuperBlock;\r
- int BlockSize;\r
- \r
- int GroupCount;\r
- tExt2_Group Groups[];\r
-} tExt2_Disk;\r
-\r
-// === PROTOTYPES ===\r
- int Ext2_Install(char **Arguments);\r
-// Interface Functions\r
-tVFS_Node *Ext2_InitDevice(char *Device, char **Options);\r
-void Ext2_Unmount(tVFS_Node *Node);\r
-Uint64 Ext2_Read(tVFS_Node *node, Uint64 offset, Uint64 length, void *buffer);\r
-Uint64 Ext2_Write(tVFS_Node *node, Uint64 offset, Uint64 length, void *buffer);\r
-void Ext2_CloseFile(tVFS_Node *Node);\r
-char *Ext2_ReadDir(tVFS_Node *Node, int Pos);\r
-tVFS_Node *Ext2_FindDir(tVFS_Node *Node, char *FileName);\r
- int Ext2_MkNod(tVFS_Node *Node, char *Name, Uint Flags);\r
-// Internal Helpers\r
- int Ext2_int_GetInode(tVFS_Node *Node, tExt2_Inode *Inode);\r
-tVFS_Node *Ext2_int_CreateNode(tExt2_Disk *Disk, Uint InodeId, char *Name);\r
- int Ext2_int_ReadInode(tExt2_Disk *Disk, Uint InodeId, tExt2_Inode *Inode);\r
-Uint64 Ext2_int_GetBlockAddr(tExt2_Disk *Disk, Uint32 *Blocks, int BlockNum);\r
-Uint32 Ext2_int_AllocateInode(tExt2_Disk *Disk, Uint32 Parent);\r
-Uint32 Ext2_int_AllocateBlock(tExt2_Disk *Disk, Uint32 PrevBlock);\r
-void Ext2_int_UpdateSuperblock(tExt2_Disk *Disk);\r
-\r
-// === SEMI-GLOBALS ===\r
-MODULE_DEFINE(0, 0x5B /*v0.90*/, EXT2, Ext2_Install, NULL);\r
-tExt2_Disk gExt2_disks[6];\r
- int giExt2_count = 0;\r
-tVFS_Driver gExt2_FSInfo = {\r
- "ext2", 0, Ext2_InitDevice, Ext2_Unmount, NULL\r
- };\r
-\r
-// === CODE ===\r
-\r
-/**\r
- * \fn int Ext2_Install(char **Arguments)\r
- * \brief Install the Ext2 Filesystem Driver\r
- */\r
-int Ext2_Install(char **Arguments)\r
-{\r
- VFS_AddDriver( &gExt2_FSInfo );\r
- return 1;\r
-}\r
-\r
-/**\r
- \fn tVFS_Node *Ext2_InitDevice(char *Device, char **Options)\r
- \brief Initializes a device to be read by by the driver\r
- \param Device String - Device to read from\r
- \param Options NULL Terminated array of option strings\r
- \return Root Node\r
-*/\r
-tVFS_Node *Ext2_InitDevice(char *Device, char **Options)\r
-{\r
- tExt2_Disk *disk;\r
- int fd;\r
- int groupCount;\r
- tExt2_SuperBlock sb;\r
- tExt2_Inode inode;\r
- \r
- ENTER("sDevice pOptions", Device, Options);\r
- \r
- // Open Disk\r
- fd = VFS_Open(Device, VFS_OPENFLAG_READ|VFS_OPENFLAG_WRITE); //Open Device\r
- if(fd == -1) {\r
- Warning("[EXT2 ] Unable to open '%s'", Device);\r
- LEAVE('n');\r
- return NULL;\r
- }\r
- \r
- // Read Superblock at offset 1024\r
- VFS_ReadAt(fd, 1024, 1024, &sb); // Read Superblock\r
- \r
- // Sanity Check Magic value\r
- if(sb.s_magic != 0xEF53) {\r
- Warning("[EXT2 ] Volume '%s' is not an EXT2 volume", Device);\r
- VFS_Close(fd);\r
- LEAVE('n');\r
- return NULL;\r
- }\r
- \r
- // Get Group count\r
- groupCount = DivUp(sb.s_blocks_count, sb.s_blocks_per_group);\r
- LOG("groupCount = %i", groupCount);\r
- \r
- // Allocate Disk Information\r
- disk = malloc(sizeof(tExt2_Disk) + sizeof(tExt2_Group)*groupCount);\r
- if(!disk) {\r
- Warning("[EXT2 ] Unable to allocate disk structure");\r
- VFS_Close(fd);\r
- LEAVE('n');\r
- return NULL;\r
- }\r
- disk->FD = fd;\r
- memcpy(&disk->SuperBlock, &sb, 1024);\r
- disk->GroupCount = groupCount;\r
- \r
- // Get an inode cache handle\r
- disk->CacheID = Inode_GetHandle();\r
- \r
- // Get Block Size\r
- LOG("s_log_block_size = 0x%x", sb.s_log_block_size);\r
- disk->BlockSize = 1024 << sb.s_log_block_size;\r
- \r
- // Read Group Information\r
- VFS_ReadAt(\r
- disk->FD,\r
- sb.s_first_data_block * disk->BlockSize + 1024,\r
- sizeof(tExt2_Group)*groupCount,\r
- disk->Groups\r
- );\r
- \r
- #if VERBOSE\r
- LOG("Block Group 0");\r
- LOG(".bg_block_bitmap = 0x%x", disk->Groups[0].bg_block_bitmap);\r
- LOG(".bg_inode_bitmap = 0x%x", disk->Groups[0].bg_inode_bitmap);\r
- LOG(".bg_inode_table = 0x%x", disk->Groups[0].bg_inode_table);\r
- LOG("Block Group 1");\r
- LOG(".bg_block_bitmap = 0x%x", disk->Groups[1].bg_block_bitmap);\r
- LOG(".bg_inode_bitmap = 0x%x", disk->Groups[1].bg_inode_bitmap);\r
- LOG(".bg_inode_table = 0x%x", disk->Groups[1].bg_inode_table);\r
- #endif\r
- \r
- // Get root Inode\r
- Ext2_int_ReadInode(disk, 2, &inode);\r
- \r
- // Create Root Node\r
- memset(&disk->RootNode, 0, sizeof(tVFS_Node));\r
- disk->RootNode.Inode = 2; // Root inode ID\r
- disk->RootNode.ImplPtr = disk; // Save disk pointer\r
- disk->RootNode.Size = -1; // Fill in later (on readdir)\r
- disk->RootNode.Flags = VFS_FFLAG_DIRECTORY;\r
- \r
- disk->RootNode.ReadDir = Ext2_ReadDir;\r
- disk->RootNode.FindDir = Ext2_FindDir;\r
- //disk->RootNode.Relink = Ext2_Relink;\r
- \r
- // Complete root node\r
- disk->RootNode.UID = inode.i_uid;\r
- disk->RootNode.GID = inode.i_gid;\r
- disk->RootNode.NumACLs = 1;\r
- disk->RootNode.ACLs = &gVFS_ACL_EveryoneRW;\r
- \r
- #if DEBUG\r
- LOG("inode.i_size = 0x%x", inode.i_size);\r
- LOG("inode.i_block[0] = 0x%x", inode.i_block[0]);\r
- #endif\r
- \r
- LEAVE('p', &disk->RootNode);\r
- return &disk->RootNode;\r
-}\r
-\r
-/**\r
- * \fn void Ext2_Unmount(tVFS_Node *Node)\r
- * \brief Close a mounted device\r
- */\r
-void Ext2_Unmount(tVFS_Node *Node)\r
-{\r
- tExt2_Disk *disk = Node->ImplPtr;\r
- \r
- VFS_Close( disk->FD );\r
- Inode_ClearCache( disk->CacheID );\r
- memset(disk, 0, sizeof(tExt2_Disk)+disk->GroupCount*sizeof(tExt2_Group));\r
- free(disk);\r
-}\r
-\r
-/**\r
- * \fn Uint64 Ext2_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)\r
- * \brief Read from a file\r
- */\r
-Uint64 Ext2_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)\r
-{\r
- tExt2_Disk *disk = Node->ImplPtr;\r
- tExt2_Inode inode;\r
- Uint64 base;\r
- Uint block;\r
- Uint64 remLen;\r
- \r
- ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);\r
- \r
- // Get Inode\r
- Ext2_int_GetInode(Node, &inode);\r
- \r
- // Sanity Checks\r
- if(Offset >= inode.i_size) {\r
- LEAVE('i', 0);\r
- return 0;\r
- }\r
- if(Offset + Length > inode.i_size)\r
- Length = inode.i_size - Offset;\r
- \r
- block = Offset / disk->BlockSize;\r
- Offset = Offset / disk->BlockSize;\r
- base = Ext2_int_GetBlockAddr(disk, inode.i_block, block);\r
- if(base == 0) {\r
- Warning("[EXT2 ] NULL Block Detected in INode 0x%llx", Node->Inode);\r
- LEAVE('i', 0);\r
- return 0;\r
- }\r
- \r
- // Read only block\r
- if(Length <= disk->BlockSize - Offset)\r
- {\r
- VFS_ReadAt( disk->FD, base+Offset, Length, Buffer);\r
- LEAVE('X', Length);\r
- return Length;\r
- }\r
- \r
- // Read first block\r
- remLen = Length;\r
- VFS_ReadAt( disk->FD, base + Offset, disk->BlockSize - Offset, Buffer);\r
- remLen -= disk->BlockSize - Offset;\r
- Buffer += disk->BlockSize - Offset;\r
- block ++;\r
- \r
- // Read middle blocks\r
- while(remLen > disk->BlockSize)\r
- {\r
- base = Ext2_int_GetBlockAddr(disk, inode.i_block, block);\r
- if(base == 0) {\r
- Warning("[EXT2 ] NULL Block Detected in INode 0x%llx", Node->Inode);\r
- LEAVE('i', 0);\r
- return 0;\r
- }\r
- VFS_ReadAt( disk->FD, base, disk->BlockSize, Buffer);\r
- Buffer += disk->BlockSize;\r
- remLen -= disk->BlockSize;\r
- block ++;\r
- }\r
- \r
- // Read last block\r
- base = Ext2_int_GetBlockAddr(disk, inode.i_block, block);\r
- VFS_ReadAt( disk->FD, base, remLen, Buffer);\r
- \r
- LEAVE('X', Length);\r
- return Length;\r
-}\r
-\r
-/**\r
- * \fn Uint64 Ext2_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)\r
- * \brief Write to a file\r
- */\r
-Uint64 Ext2_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)\r
-{\r
- tExt2_Disk *disk = Node->ImplPtr;\r
- tExt2_Inode inode;\r
- Uint64 base;\r
- Uint64 retLen;\r
- Uint block;\r
- Uint64 allocSize;\r
- int bNewBlocks = 0;\r
- \r
- Debug_HexDump("Ext2_Write", Buffer, Length);\r
- \r
- Ext2_int_GetInode(Node, &inode);\r
- \r
- // Get the ammount of space already allocated\r
- // - Round size up to block size\r
- // - block size is a power of two, so this will work\r
- allocSize = (inode.i_size + disk->BlockSize) & ~(disk->BlockSize-1);\r
- \r
- // Are we writing to inside the allocated space?\r
- if( Offset < allocSize )\r
- {\r
- // Will we go out of it?\r
- if(Offset + Length > allocSize) {\r
- bNewBlocks = 1;\r
- retLen = allocSize - Offset;\r
- } else\r
- retLen = Length;\r
- \r
- // Within the allocated space\r
- block = Offset / disk->BlockSize;\r
- Offset %= disk->BlockSize;\r
- base = Ext2_int_GetBlockAddr(disk, inode.i_block, block);\r
- \r
- // Write only block (if only one)\r
- if(Offset + retLen <= disk->BlockSize) {\r
- VFS_WriteAt(disk->FD, base+Offset, retLen, Buffer);\r
- if(!bNewBlocks) return Length;\r
- goto addBlocks; // Ugh! A goto, but it seems unavoidable\r
- }\r
- \r
- // Write First Block\r
- VFS_WriteAt(disk->FD, base+Offset, disk->BlockSize-Offset, Buffer);\r
- Buffer += disk->BlockSize-Offset;\r
- retLen -= disk->BlockSize-Offset;\r
- block ++;\r
- \r
- // Write middle blocks\r
- while(retLen > disk->BlockSize)\r
- {\r
- base = Ext2_int_GetBlockAddr(disk, inode.i_block, block);\r
- VFS_WriteAt(disk->FD, base, disk->BlockSize, Buffer);\r
- Buffer += disk->BlockSize;\r
- retLen -= disk->BlockSize;\r
- block ++;\r
- }\r
- \r
- // Write last block\r
- base = Ext2_int_GetBlockAddr(disk, inode.i_block, block);\r
- VFS_WriteAt(disk->FD, base, retLen, Buffer);\r
- if(!bNewBlocks) return Length; // Writing in only allocated space\r
- }\r
- \r
-addBlocks:\r
- ///\todo Implement block allocation\r
- Warning("[EXT2] File extending is not yet supported");\r
- \r
- return 0;\r
-}\r
-\r
-/**\r
- * \fn void Ext2_CloseFile(tVFS_Node *Node)\r
- * \brief Close a file (Remove it from the cache)\r
- */\r
-void Ext2_CloseFile(tVFS_Node *Node)\r
-{\r
- tExt2_Disk *disk = Node->ImplPtr;\r
- Inode_UncacheNode(disk->CacheID, Node->Inode);\r
- return ;\r
-}\r
-\r
-/**\r
- \fn char *Ext2_ReadDir(tVFS_Node *Node, int Pos)\r
- \brief Reads a directory entry\r
-*/\r
-char *Ext2_ReadDir(tVFS_Node *Node, int Pos)\r
-{\r
- tExt2_Inode inode;\r
- char namebuf[EXT2_NAME_LEN+1];\r
- tExt2_DirEnt dirent;\r
- Uint64 Base; // Block's Base Address\r
- int block = 0, ofs = 0;\r
- int entNum = 0;\r
- tExt2_Disk *disk = Node->ImplPtr;\r
- Uint size;\r
- \r
- ENTER("pNode iPos", Node, Pos);\r
- \r
- // Read directory's inode\r
- Ext2_int_GetInode(Node, &inode);\r
- size = inode.i_size;\r
- \r
- LOG("inode.i_block[0] = 0x%x", inode.i_block[0]);\r
- \r
- // Find Entry\r
- // Get First Block\r
- // - Do this ourselves as it is a simple operation\r
- Base = inode.i_block[0] * disk->BlockSize;\r
- while(Pos -- && size > 0)\r
- {\r
- VFS_ReadAt( disk->FD, Base+ofs, sizeof(tExt2_DirEnt), &dirent);\r
- ofs += dirent.rec_len;\r
- size -= dirent.rec_len;\r
- entNum ++;\r
- \r
- if(ofs >= disk->BlockSize) {\r
- block ++;\r
- if( ofs > disk->BlockSize ) {\r
- Warning("[EXT2] Directory Entry %i of inode %i extends over a block boundary, ignoring",\r
- entNum-1, Node->Inode);\r
- }\r
- ofs = 0;\r
- Base = Ext2_int_GetBlockAddr( disk, inode.i_block, block );\r
- }\r
- }\r
- \r
- // Check for the end of the list\r
- if(size <= 0) {\r
- LEAVE('n');\r
- return NULL;\r
- }\r
- \r
- // Read Entry\r
- VFS_ReadAt( disk->FD, Base+ofs, sizeof(tExt2_DirEnt), &dirent );\r
- //LOG("dirent.inode = %i", dirent.inode);\r
- //LOG("dirent.rec_len = %i", dirent.rec_len);\r
- //LOG("dirent.name_len = %i", dirent.name_len);\r
- VFS_ReadAt( disk->FD, Base+ofs+sizeof(tExt2_DirEnt), dirent.name_len, namebuf );\r
- namebuf[ dirent.name_len ] = '\0'; // Cap off string\r
- \r
- \r
- // Ignore . and .. (these are done in the VFS)\r
- if( (namebuf[0] == '.' && namebuf[1] == '\0')\r
- || (namebuf[0] == '.' && namebuf[1] == '.' && namebuf[2]=='\0')) {\r
- LEAVE('p', VFS_SKIP);\r
- return VFS_SKIP; // Skip\r
- }\r
- \r
- LEAVE('s', namebuf);\r
- // Create new node\r
- return strdup(namebuf);\r
-}\r
-\r
-/**\r
- \fn tVFS_Node *Ext2_FindDir(tVFS_Node *node, char *filename)\r
- \brief Gets information about a file\r
- \param node vfs node - Parent Node\r
- \param filename String - Name of file\r
- \return VFS Node of file\r
-*/\r
-tVFS_Node *Ext2_FindDir(tVFS_Node *Node, char *Filename)\r
-{\r
- tExt2_Disk *disk = Node->ImplPtr;\r
- tExt2_Inode inode;\r
- char namebuf[EXT2_NAME_LEN+1];\r
- tExt2_DirEnt dirent;\r
- Uint64 Base; // Block's Base Address\r
- int block = 0, ofs = 0;\r
- int entNum = 0;\r
- Uint size;\r
- \r
- // Read directory's inode\r
- Ext2_int_GetInode(Node, &inode);\r
- size = inode.i_size;\r
- \r
- // Get First Block\r
- // - Do this ourselves as it is a simple operation\r
- Base = inode.i_block[0] * disk->BlockSize;\r
- // Find File\r
- while(size > 0)\r
- {\r
- VFS_ReadAt( disk->FD, Base+ofs, sizeof(tExt2_DirEnt), &dirent);\r
- VFS_ReadAt( disk->FD, Base+ofs+sizeof(tExt2_DirEnt), dirent.name_len, namebuf );\r
- namebuf[ dirent.name_len ] = '\0'; // Cap off string\r
- // If it matches, create a node and return it\r
- if(strcmp(namebuf, Filename) == 0)\r
- return Ext2_int_CreateNode( disk, dirent.inode, namebuf );\r
- // Increment pointers\r
- ofs += dirent.rec_len;\r
- size -= dirent.rec_len;\r
- entNum ++;\r
- \r
- // Check for end of block\r
- if(ofs >= disk->BlockSize) {\r
- block ++;\r
- if( ofs > disk->BlockSize ) {\r
- Warning("[EXT2 ] Directory Entry %i of inode %i extends over a block boundary, ignoring",\r
- entNum-1, Node->Inode);\r
- }\r
- ofs = 0;\r
- Base = Ext2_int_GetBlockAddr( disk, inode.i_block, block );\r
- }\r
- }\r
- \r
- return NULL;\r
-}\r
-\r
-/**\r
- * \fn int Ext2_MkNod(tVFS_Node *Parent, char *Name, Uint Flags)\r
- * \brief Create a new node\r
- */\r
-int Ext2_MkNod(tVFS_Node *Parent, char *Name, Uint Flags)\r
-{\r
- return 0;\r
-}\r
-\r
-//==================================\r
-//= INTERNAL FUNCTIONS =\r
-//==================================\r
-\r
-\r
-/**\r
- * \fn int Ext2_int_GetInode(tVFS_Node *Node, tExt2_Inode *Inode)\r
- * \brief Gets the inode descriptor for a node\r
- * \param Node node to get the Inode of\r
- * \param Inode Destination\r
- */\r
-int Ext2_int_GetInode(tVFS_Node *Node, tExt2_Inode *Inode)\r
-{\r
- return Ext2_int_ReadInode(Node->ImplPtr, Node->Inode, Inode);\r
-}\r
-\r
-/**\r
- * \fn vfs_node *Ext2_int_CreateNode(tExt2_Disk *Disk, Uint InodeID, char *Name)\r
- * \brief Create a new VFS Node\r
- */\r
-tVFS_Node *Ext2_int_CreateNode(tExt2_Disk *Disk, Uint InodeID, char *Name)\r
-{\r
- tExt2_Inode inode;\r
- tVFS_Node retNode;\r
- tVFS_Node *tmpNode;\r
- \r
- if( !Ext2_int_ReadInode(Disk, InodeID, &inode) )\r
- return NULL;\r
- \r
- if( (tmpNode = Inode_GetCache(Disk->CacheID, InodeID)) )\r
- return tmpNode;\r
- \r
- \r
- // Set identifiers\r
- retNode.Inode = InodeID;\r
- retNode.ImplPtr = Disk;\r
- \r
- // Set file length\r
- retNode.Size = inode.i_size;\r
- \r
- // Set Access Permissions\r
- retNode.UID = inode.i_uid;\r
- retNode.GID = inode.i_gid;\r
- retNode.NumACLs = 3;\r
- retNode.ACLs = VFS_UnixToAcessACL(inode.i_mode & 0777, inode.i_uid, inode.i_gid);\r
- \r
- // Set Function Pointers\r
- retNode.Read = Ext2_Read;\r
- retNode.Write = Ext2_Write;\r
- retNode.Close = Ext2_CloseFile;\r
- \r
- switch(inode.i_mode & EXT2_S_IFMT)\r
- {\r
- // Symbolic Link\r
- case EXT2_S_IFLNK:\r
- retNode.Flags = VFS_FFLAG_SYMLINK;\r
- break;\r
- // Regular File\r
- case EXT2_S_IFREG:\r
- retNode.Flags = 0;\r
- retNode.Size |= (Uint64)inode.i_dir_acl << 32;\r
- break;\r
- // Directory\r
- case EXT2_S_IFDIR:\r
- retNode.ReadDir = Ext2_ReadDir;\r
- retNode.FindDir = Ext2_FindDir;\r
- retNode.MkNod = Ext2_MkNod;\r
- //retNode.Relink = Ext2_Relink;\r
- retNode.Flags = VFS_FFLAG_DIRECTORY;\r
- break;\r
- // Unknown, Write protect and hide it to be safe \r
- default:\r
- retNode.Flags = VFS_FFLAG_READONLY;//|VFS_FFLAG_HIDDEN;\r
- break;\r
- }\r
- \r
- // Check if the file should be hidden\r
- //if(Name[0] == '.') retNode.Flags |= VFS_FFLAG_HIDDEN;\r
- \r
- // Set Timestamps\r
- retNode.ATime = now();\r
- retNode.MTime = inode.i_mtime * 1000;\r
- retNode.CTime = inode.i_ctime * 1000;\r
- \r
- // Save in node cache and return saved node\r
- return Inode_CacheNode(Disk->CacheID, &retNode);\r
-}\r
-\r
-/**\r
- * \fn int Ext2_int_ReadInode(tExt2_Disk *Disk, Uint InodeId, tExt2_Inode *Inode)\r
- * \brief Read an inode into memory\r
- */\r
-int Ext2_int_ReadInode(tExt2_Disk *Disk, Uint InodeId, tExt2_Inode *Inode)\r
-{\r
- int group, subId;\r
- \r
- //LogF("Ext2_int_ReadInode: (Disk=%p, InodeId=%i, Inode=%p)", Disk, InodeId, Inode);\r
- //ENTER("pDisk iInodeId pInode", Disk, InodeId, Inode);\r
- \r
- if(InodeId == 0) return 0;\r
- \r
- InodeId --; // Inodes are numbered starting at 1\r
- \r
- group = InodeId / Disk->SuperBlock.s_inodes_per_group;\r
- subId = InodeId % Disk->SuperBlock.s_inodes_per_group;\r
- \r
- //LOG("group=%i, subId = %i", group, subId);\r
- \r
- // Read Inode\r
- VFS_ReadAt(Disk->FD,\r
- Disk->Groups[group].bg_inode_table * Disk->BlockSize + sizeof(tExt2_Inode)*subId,\r
- sizeof(tExt2_Inode),\r
- Inode);\r
- return 1;\r
-}\r
-\r
-/**\r
- * \fn Uint64 Ext2_int_GetBlockAddr(tExt2_Disk *Disk, Uint32 *Blocks, int BlockNum)\r
- * \brief Get the address of a block from an inode's list\r
- * \param Disk Disk information structure\r
- * \param Blocks Pointer to an inode's block list\r
- * \param BlockNum Block index in list\r
- */\r
-Uint64 Ext2_int_GetBlockAddr(tExt2_Disk *Disk, Uint32 *Blocks, int BlockNum)\r
-{\r
- Uint32 *iBlocks;\r
- // Direct Blocks\r
- if(BlockNum < 12)\r
- return (Uint64)Blocks[BlockNum] * Disk->BlockSize;\r
- \r
- // Single Indirect Blocks\r
- iBlocks = malloc( Disk->BlockSize );\r
- VFS_ReadAt(Disk->FD, (Uint64)Blocks[12]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
- \r
- BlockNum -= 12;\r
- if(BlockNum < 256) {\r
- BlockNum = iBlocks[BlockNum];\r
- free(iBlocks);\r
- return (Uint64)BlockNum * Disk->BlockSize;\r
- }\r
- \r
- // Double Indirect Blocks\r
- if(BlockNum < 256*256)\r
- {\r
- VFS_ReadAt(Disk->FD, (Uint64)Blocks[13]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
- VFS_ReadAt(Disk->FD, (Uint64)iBlocks[BlockNum/256]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
- BlockNum = iBlocks[BlockNum%256];\r
- free(iBlocks);\r
- return (Uint64)BlockNum * Disk->BlockSize;\r
- }\r
- // Triple Indirect Blocks\r
- VFS_ReadAt(Disk->FD, (Uint64)Blocks[14]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
- VFS_ReadAt(Disk->FD, (Uint64)iBlocks[BlockNum/(256*256)]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
- VFS_ReadAt(Disk->FD, (Uint64)iBlocks[(BlockNum/256)%256]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
- BlockNum = iBlocks[BlockNum%256];\r
- free(iBlocks);\r
- return (Uint64)BlockNum * Disk->BlockSize;\r
-}\r
-\r
-/**\r
- * \fn Uint32 Ext2_int_AllocateInode(tExt2_Disk *Disk, Uint32 Parent)\r
- * \brief Allocate an inode (from the current group preferably)\r
- * \param Disk EXT2 Disk Information Structure\r
- * \param Parent Inode ID of the parent (used to locate the child nearby)\r
- */\r
-Uint32 Ext2_int_AllocateInode(tExt2_Disk *Disk, Uint32 Parent)\r
-{\r
-// Uint block = (Parent - 1) / Disk->SuperBlock.s_inodes_per_group;\r
- return 0;\r
-}\r
-\r
-/**\r
- * \fn Uint32 Ext2_int_AllocateBlock(tExt2_Disk *Disk, Uint32 PrevBlock)\r
- * \brief Allocate a block from the best possible location\r
- * \param Disk EXT2 Disk Information Structure\r
- * \param PrevBlock Previous block ID in the file\r
- */\r
-Uint32 Ext2_int_AllocateBlock(tExt2_Disk *Disk, Uint32 PrevBlock)\r
-{\r
- int bpg = Disk->SuperBlock.s_blocks_per_group;\r
- Uint blockgroup = PrevBlock / bpg;\r
- Uint bitmap[Disk->BlockSize/sizeof(Uint)];\r
- Uint bitsperblock = 8*Disk->BlockSize;\r
- int i, j = 0;\r
- Uint block;\r
- \r
- // Are there any free blocks?\r
- if(Disk->SuperBlock.s_free_blocks_count == 0) return 0;\r
- \r
- if(Disk->Groups[blockgroup].bg_free_blocks_count > 0)\r
- {\r
- // Search block group's bitmap\r
- for(i = 0; i < bpg; i++)\r
- {\r
- // Get the block in the bitmap block\r
- j = i & (bitsperblock-1);\r
- \r
- // Read in if needed\r
- if(j == 0) {\r
- VFS_ReadAt(\r
- Disk->FD,\r
- (Uint64)Disk->Groups[blockgroup].bg_block_bitmap + i / bitsperblock,\r
- Disk->BlockSize,\r
- bitmap\r
- );\r
- }\r
- \r
- // Fast Check\r
- if( bitmap[j/32] == -1 ) {\r
- j = (j + 31) & ~31;\r
- continue;\r
- }\r
- \r
- // Is the bit set?\r
- if( bitmap[j/32] & (1 << (j%32)) )\r
- continue;\r
- \r
- // Ooh! We found one\r
- break;\r
- }\r
- if( i < bpg ) {\r
- Warning("[EXT2 ] Inconsistency detected, Group Free Block count is non-zero when no free blocks exist");\r
- goto checkAll; // Search the entire filesystem for a free block\r
- // Goto needed for neatness\r
- }\r
- \r
- // Mark as used\r
- bitmap[j/32] |= (1 << (j%32));\r
- VFS_WriteAt(\r
- Disk->FD,\r
- (Uint64)Disk->Groups[blockgroup].bg_block_bitmap + i / bitsperblock,\r
- Disk->BlockSize,\r
- bitmap\r
- );\r
- block = i;\r
- Disk->Groups[blockgroup].bg_free_blocks_count --;\r
- }\r
- else\r
- {\r
- checkAll:\r
- Warning("[EXT2 ] TODO - Implement using blocks outside the current block group");\r
- return 0;\r
- }\r
- \r
- // Reduce global count\r
- Disk->SuperBlock.s_free_blocks_count --;\r
- #if EXT2_UPDATE_WRITEBACK\r
- Ext2_int_UpdateSuperblock(Disk);\r
- #endif\r
- \r
- return block;\r
-}\r
-\r
-/**\r
- * \fn void Ext2_int_UpdateSuperblock(tExt2_Disk *Disk)\r
- */\r
-void Ext2_int_UpdateSuperblock(tExt2_Disk *Disk)\r
-{\r
- VFS_WriteAt(Disk->FD, 1024, 1024, &Disk->SuperBlock);\r
-}\r
git.ucc.asn.au / tpg / acess2.git / blobdiff
UCC git Repository :: git.ucc.asn.au