--- /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 "ext2_common.h"\r
+#include <modules.h>\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
+void Ext2_CloseFile(tVFS_Node *Node);\r
+// Internal Helpers\r
+ int Ext2_int_GetInode(tVFS_Node *Node, 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
+void Ext2_int_UpdateSuperblock(tExt2_Disk *Disk);\r
+\r
+// === SEMI-GLOBALS ===\r
+MODULE_DEFINE(0, 0x5B /*v0.90*/, FS_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 MODULE_ERR_OK;\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 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
+//= INTERNAL FUNCTIONS =\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, Uint32 InodeId, tExt2_Inode *Inode)\r
+{\r
+ int group, subId;\r
+ \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
+ \r
+ //LEAVE('i', 1);\r
+ return 1;\r
+}\r
+\r
+/**\r
+ * \brief Write a modified inode out to disk\r
+ */\r
+int Ext2_int_WriteInode(tExt2_Disk *Disk, Uint32 InodeId, tExt2_Inode *Inode)\r
+{\r
+ int group, subId;\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
+ // Write Inode\r
+ VFS_WriteAt(Disk->FD,\r
+ Disk->Groups[group].bg_inode_table * Disk->BlockSize + sizeof(tExt2_Inode)*subId,\r
+ sizeof(tExt2_Inode),\r
+ Inode);\r
+ \r
+ LEAVE('i', 1);\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
+ int dwPerBlock = Disk->BlockSize / 4;\r
+ \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 < dwPerBlock)\r
+ {\r
+ BlockNum = iBlocks[BlockNum];\r
+ free(iBlocks);\r
+ return (Uint64)BlockNum * Disk->BlockSize;\r
+ }\r
+ \r
+ BlockNum -= dwPerBlock;\r
+ // Double Indirect Blocks\r
+ if(BlockNum < dwPerBlock*dwPerBlock)\r
+ {\r
+ VFS_ReadAt(Disk->FD, (Uint64)Blocks[13]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
+ VFS_ReadAt(Disk->FD, (Uint64)iBlocks[BlockNum/dwPerBlock]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
+ BlockNum = iBlocks[BlockNum%dwPerBlock];\r
+ free(iBlocks);\r
+ return (Uint64)BlockNum * Disk->BlockSize;\r
+ }\r
+ \r
+ BlockNum -= dwPerBlock*dwPerBlock;\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/(dwPerBlock*dwPerBlock)]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
+ VFS_ReadAt(Disk->FD, (Uint64)iBlocks[(BlockNum/dwPerBlock)%dwPerBlock]*Disk->BlockSize, Disk->BlockSize, iBlocks);\r
+ BlockNum = iBlocks[BlockNum%dwPerBlock];\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 void Ext2_int_UpdateSuperblock(tExt2_Disk *Disk)\r
+ * \brief Updates the superblock\r
+ */\r
+void Ext2_int_UpdateSuperblock(tExt2_Disk *Disk)\r
+{\r
+ int bpg = Disk->SuperBlock.s_blocks_per_group;\r
+ int ngrp = Disk->SuperBlock.s_blocks_count / bpg;\r
+ int i;\r
+ \r
+ // Update Primary\r
+ VFS_WriteAt(Disk->FD, 1024, 1024, &Disk->SuperBlock);\r
+ \r
+ // Secondaries\r
+ // at Block Group 1, 3^n, 5^n, 7^n\r
+ \r
+ // 1\r
+ if(ngrp <= 1) return;\r
+ VFS_WriteAt(Disk->FD, 1*bpg*Disk->BlockSize, 1024, &Disk->SuperBlock);\r
+ \r
+ // Powers of 3\r
+ for( i = 3; i < ngrp; i *= 3 )\r
+ VFS_WriteAt(Disk->FD, i*bpg*Disk->BlockSize, 1024, &Disk->SuperBlock);\r
+ \r
+ // Powers of 5\r
+ for( i = 5; i < ngrp; i *= 5 )\r
+ VFS_WriteAt(Disk->FD, i*bpg*Disk->BlockSize, 1024, &Disk->SuperBlock);\r
+ \r
+ // Powers of 7\r
+ for( i = 7; i < ngrp; i *= 7 )\r
+ VFS_WriteAt(Disk->FD, i*bpg*Disk->BlockSize, 1024, &Disk->SuperBlock);\r
+}\r
git.ucc.asn.au / tpg / acess2.git / blobdiff
UCC git Repository :: git.ucc.asn.au