Nigel
/
BarinkOS
1
0
Fork 0
Code Issues 1 Pull Requests 2 Releases Activity

We can now open and read files on the harddisk through a messy virtual filesystem 

The uri has to contain 8.3 filenames for now as I have not yet figured out
how to convert from that to regular filenaming for the name comparison.

reading files is still limited to 1 sector
dev
Nigel Barink 2023-02-26 13:44:41 +01:00
parent 61f1852420
commit e6901f0526
12 changed files with 310 additions and 385 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
CoreLib/List.h Normal file
View File

@ -0,0 +1,12 @@
//
// Created by nigel on 25/02/23.
//
#pragma once
class List {
public:
List* next;
void* data;
};

2
CoreLib/Memory.cpp
View File

@ -32,7 +32,7 @@ int memcmp( const void* ptr1, const void* ptr2, size_t num)
}
void memcpy (void* dest, const void* src, size_t count ){
[[maybe_unused]] void memcpy (void* dest, const void* src, size_t count ){
for( int i = 0; i < count; i++){
((char *)dest)[i] = ((const char*)src)[i];
}

2
CoreLib/Memory.h
View File

@ -7,7 +7,7 @@ void* memset (void* ptr, int value, size_t num);
int memcmp( const void* ptr1, const void* ptr2, size_t num);
void memcpy (void* dest, const void* src, size_t count );
[[maybe_unused]] void memcpy (void* dest, const void* src, size_t count );
size_t strlen(const char* str);

2
README.md
View File

@ -27,7 +27,7 @@ Enumerating the PCI bus
Correctly identified our ATAPI device 🎉
![Reading Files from FAT-16](screenshots/ReadingFilesFromFAT16.png) \
Reading a file from a FAT-16 Formatted drive
Reading a FILE from a FAT-16 Formatted drive
________________________

95
kernel/kernel.cpp
View File

@ -16,6 +16,7 @@
#include "serial.h"
#include "storage/vfs/vfs.h"
#include "storage/filesystems/FAT/FAT.h"
#include "../CoreLib/Memory.h"
extern "C" void LoadGlobalDescriptorTable();
@ -57,86 +58,26 @@ extern "C" void kernel ()
printf("Part1: %d, Part2: %d, Part3: %d\n", part1, part2 , part3);
ATAPIO::Identify(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER);
auto* bpb = FAT::getBPB(false);
auto* mbr = GetPartitions(false);
auto fsType = FAT::determineFATType(bpb);
switch (fsType) {
case FAT_TYPE::FAT12:
printf("FAT12 Disk!\n");
break;
case FAT_TYPE::FAT16:
printf("FAT16 Disk!\n");
break;
case FAT_TYPE::FAT32:
printf("FAT32 Disk!\n");
break;
VirtualFileSystem::initialize();
printf("Lets open hello.txt\n");
auto fontFile = VirtualFileSystem::open("/HELLO TXT", 0);
if(fontFile->flags == 0){
uint16_t* contents = (uint16_t*) malloc(sizeof(uint16_t) * 256);
fontFile->read(fontFile, contents, 512);
for(int i =0 ; i < fontFile->root->size; i++ ){
kterm_put(contents[i] & 0x00ff);
kterm_put(contents[i] >> 8);
}
kterm_put('\n');
free((void*)contents);
}else{
printf("Could not find file\n");
}
// list files in root
int total_sectors = bpb->TotSec32;
int fat_size = bpb->FATSz16;
int root_dir_sectors = FAT::RootDirSize(bpb);
int first_data_sector = bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sectors ;
int data_sectors = bpb->TotSec32 - (bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sectors);
int total_clusters = data_sectors / bpb->SecPerClus;
int first_root_dir_sector = first_data_sector - root_dir_sectors;
//int first_sector_of_cluster = ((cluster - 2) * bpb->SecPerClus) + first_data_sector;
uint16_t data[256];
ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, first_root_dir_sector, data);
auto* RootDirectory = (DIR*)data;
for(int i = 0; i < sizeof(data) / sizeof (DIR); i++)
{
DIR* entry = (DIR*)((uint32_t)RootDirectory + (i * sizeof(DIR)));
if(entry->Name[0] == FAT::FREE_DIR || entry->Name[0] == FAT::FREE_DIR_2 || entry->Name[0] == 0xE5){
continue;
}
if(entry->ATTR & FAT::ATTRIBUTES::ATTR_HIDDEN){
continue;
}
if(entry->ATTR & FAT::ATTRIBUTES::ATTR_SYSTEM)
continue;
if(entry->ATTR & FAT::ATTRIBUTES::ATTR_VOLUME_ID){
continue;
}
if (!(entry->ATTR & FAT::ATTRIBUTES::ATTR_LONG_NAME)){
for(char n : entry->Name){
if(n == 0x20)
continue;
kterm_put(n);
}
}else{
printf("Long file name detected!");
}
printf(" [Size: %d bytes, Attributes: %d]\n", entry->ATTR, entry->FileSize);
if(entry->ATTR & FAT::ATTRIBUTES::ATTR_DIRECTORY ){
FAT::OpenSubdir(entry, bpb);
} else {
FAT::readFile(entry, bpb);
}
}
// VirtualFileSystem::initialize();
// VirtualFileSystem::open("/hello.txt", 0);
#ifdef USERMODE_RELEASE
// Lets jump into user mode

340
kernel/storage/filesystems/FAT/FAT.cpp
View File

@ -4,10 +4,14 @@
#include "FAT.h"
#include "../../ata pio/ATAPIO.h"
#include "../../../memory/KernelHeap.h"
#include "../../../../CoreLib/Memory.h"
#include "../../partitiontables/mbr/MasterBootRecord.h"
#include "../../../../CoreLib/ctype.h"
#include "../../../../CoreLib/Memory.h"
#include <CoreLib/Memory.h>
superblock* FAT::Mount(filesystem *fs, const char* name ,vfsmount *mnt)
#include <CoreLib/ctype.h>
// exposed driver API
FS_SUPER* FAT::Mount(filesystem *fs, const char* name , vfsmount *mnt)
{
if( strncmp (fs->name, "fat", 3 ) != 0 )
@ -15,58 +19,138 @@ superblock* FAT::Mount(filesystem *fs, const char* name ,vfsmount *mnt)
printf("Can't mount filesystem with none fat type!\n");
return nullptr;
}
auto* bpb = GetBiosParameterBlock();
auto fat_type = DetermineFATType(bpb);
superblock* sb = (superblock*) malloc(sizeof(superblock));
directoryEntry* root = (directoryEntry*) malloc(sizeof (directoryEntry));
if(fat_type != FAT_TYPE::FAT16)
return nullptr;
FS_SUPER* sb = (FS_SUPER*) malloc(sizeof(FS_SUPER));
DirectoryNode* root = (DirectoryNode*) malloc(sizeof (DirectoryNode));
inode* node = (inode*) malloc(sizeof(inode));
root->children = nullptr;
node->internal = (void*)FAT::GetSectorOfRootDirectory(bpb); //sector number;
node->lookup = FAT::Lookup;
root->name = (char*) name;
root->node = nullptr;
root->node = node;
root->parent = nullptr;
dentry_operations* op = (dentry_operations*) malloc(sizeof(dentry_operations));
op->compare = FAT::compare;
root->op = op;
root->compare = FAT::Compare;
mnt->mnt_count =1;
mnt->mnt_devname = "QEMU HDD";
mnt->mnt_flags = 0;
mnt->mnt_parent = nullptr;
mnt->root = root;
mnt->sb = sb;
sb->type = fs;
sb->root = root;
//sb->fs_info = getBPB();
sb->fs_info = bpb;
return sb;
}
int FAT::Read(file* file, void* buffer , int length)
{
return 0;
}
int FAT::Write(file* file, const void* buffer, int length)
{
return 0;
}
int FAT::compare (directoryEntry*, char* filename, char* filename2)
{
// use the size of the smallest string
int a = strlen(filename);
int b = strlen(filename2);
FILE FAT::Open(char* filename){
if( a == b ){
return strncmp(filename, filename2, a);
return (FILE){nullptr, 0, nullptr, nullptr, 1} ;
}
int FAT::Read(FILE* file, void* buffer , unsigned int length)
{
if(file == nullptr)
{
printf("NO FILE!!\n");
return -1;
}
return a-b;
inode* node = file->root;
if(node== nullptr)
{
printf("No INODE!\n");
return -1;
}
int cluster = (int)node->internal;
auto* bpb = FAT::GetBiosParameterBlock();
unsigned int FAT_entry = FAT::GetFATEntry(bpb, cluster);
unsigned int root_dir_sector = FAT::RootDirSize(bpb);
unsigned int fat_size = bpb->FATSz16;
unsigned int first_data_sector = bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sector;
unsigned int file_data_sector = ((cluster - 2) * bpb->SecPerClus) + first_data_sector;
ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, file_data_sector, (uint16_t*)buffer);
return 0;
}
int FAT::create(inode* dir_node, inode** target, const char* component_name){}
int FAT::lookup (inode*, inode**, const char*){}
int FAT::Write(FILE* file, const void* buffer, unsigned int length)
{
return 0;
}
int FAT::Compare (DirectoryNode*, char* filename, char* filename2)
{
//TODO Implement proper compare method for 8.3 filenames
// printf("COMPARE: %s with %s\n", filename, filename2);
return memcmp(filename, filename2, 11);
}
int FAT::Create(inode* dir_node, inode** target, const char* component_name){}
DirectoryNode* FAT::Lookup (inode* currentDir , DirectoryNode* dir)
{
uint16_t data[256];
ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, (int)currentDir->internal , data);
List* lastAdded = nullptr;
auto* directory = (DIR*)data;
for(int i = 0; i < sizeof(data) / sizeof (DIR); i++)
{
DIR* entry = (DIR*)((uint32_t)directory + (i * sizeof(DIR)));
if(
entry->Name[0] == FAT::FREE_DIR ||
entry->Name[0] == FAT::FREE_DIR_2 ||
entry->Name[0] == 0xE5 ||
entry->ATTR & FAT::ATTRIBUTES::ATTR_VOLUME_ID ||
entry->ATTR & FAT::ATTRIBUTES::ATTR_SYSTEM ||
entry->ATTR & FAT::ATTRIBUTES::ATTR_HIDDEN
){
continue;
}
auto* dirNode = (DirectoryNode*) malloc(sizeof (DirectoryNode));
char* name = (char*)malloc(sizeof(char[11]));
memcpy(name, entry->Name, 11 );
dirNode->name = name;
dirNode->compare = dir->compare;
dirNode->parent = dir;
dirNode->node= (inode*) malloc(sizeof (inode));
dirNode->node->internal = (void*)entry->FstClusLo;
dirNode->node->read = currentDir->read;
dirNode->node->lookup = currentDir->lookup;
dirNode->node->sb = currentDir->sb;
dirNode->node->size = entry->FileSize;
List* dirlist = (List*) malloc(sizeof (List));
dirlist->data = dirNode;
dirlist->next = nullptr;
lastAdded = dirlist;
auto* temp = dir->children;
dir->children = lastAdded;
lastAdded->next = temp;
FAT_TYPE FAT::determineFATType(BiosParameterBlock* bpb){
}
return (DirectoryNode*)dir;
}
// internal functions
FAT_TYPE FAT::DetermineFATType(BiosParameterBlock* bpb){
int RootDirSector = ((bpb->RootEntCnt * 32) + (bpb->BytsPerSec -1)) / bpb->BytsPerSec;
int FATSz = 0;
if(bpb->FATSz16 != 0){
@ -93,7 +177,7 @@ FAT_TYPE FAT::determineFATType(BiosParameterBlock* bpb){
return FAT_TYPE::FAT32;
}
};
BiosParameterBlock* FAT::getBPB( bool DEBUG ){
BiosParameterBlock* FAT::GetBiosParameterBlock(bool DEBUG ){
BiosParameterBlock* bpb = (BiosParameterBlock*) malloc(sizeof(BiosParameterBlock));
uint16_t StartAddress = 0x00 ;
ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, StartAddress, (uint16_t*) bpb);
@ -114,24 +198,20 @@ BiosParameterBlock* FAT::getBPB( bool DEBUG ){
}
uint16_t FAT::GetFATEntry (BiosParameterBlock* bpb, unsigned int cluster){
int FATSz = bpb->FATSz16;
int FATOffset = 0;
FAT_TYPE type = FAT::determineFATType(bpb);
FAT_TYPE type = FAT::DetermineFATType(bpb);
if( type == FAT_TYPE::FAT16){
FATOffset = cluster *2;
} else if( type == FAT_TYPE::FAT32){
FATOffset = cluster * 4;
}
int thisFATSecNum = bpb->RsvdSecCnt + (FATOffset / bpb->BytsPerSec); // Sector number containing the entry for the cluster
// For any other FAT other than the default
// SectorNumber = (FATNumber * FATSz) + ThisFATSecNum
uint16_t buff[bpb->BytsPerSec];
ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, thisFATSecNum, buff );
int thisFATEntOffset = FATOffset % bpb->BytsPerSec; // offset for the entry in the sector containing the entry for the cluster
uint16_t ClusterEntryValue = 0;
// Get the FATEntry
@ -145,7 +225,6 @@ uint16_t FAT::GetFATEntry (BiosParameterBlock* bpb, unsigned int cluster){
}
}
uint16_t FAT::DetermineFreeSpace()
{
// Loop through all FAT entries in all FAT's
@ -166,35 +245,15 @@ the FAT entry for the last cluster) must be set to 0x0 during volume initializat
}
int FAT::GetSectorOfRootDirectory (BiosParameterBlock* bpb)
{
return (bpb->RsvdSecCnt + (bpb->NumFATs * bpb->FATSz16));
}
unsigned int FAT::RootDirSize(BiosParameterBlock* bpb)
{
return ((bpb->RootEntCnt * 32) + (bpb->BytsPerSec -1)) /bpb->BytsPerSec;
}
uint16_t* ReadFAT (BiosParameterBlock& bpb , bool DEBUG = false ) {
uint32_t FATAddress = /*StartAddress*/ 0x00 + bpb.RsvdSecCnt ;
uint16_t* FAT = (uint16_t*)malloc(sizeof (uint16_t) * 256);
ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, FATAddress, FAT );
// Show data in terminal
if(DEBUG){
for( unsigned int i =0 ; i < 256 ; i++) {
printf("0x%x ", (unsigned short)FAT[i]);
}
kterm_put('\n');
}
return FAT;
}
void FAT::OpenSubdir(DIR* directory, BiosParameterBlock* bpb ){
unsigned int cluster = directory->FstClusLo;
@ -252,9 +311,9 @@ void FAT::OpenSubdir(DIR* directory, BiosParameterBlock* bpb ){
}
}
void FAT::readFile(DIR* fileEntry , BiosParameterBlock* bpb){
void FAT::ReadFileContents(DIR* fileEntry , BiosParameterBlock* bpb){
unsigned int cluster = fileEntry->FstClusLo;
printf("cluster NR: %x\n", cluster);
unsigned int FATEntry = FAT::GetFATEntry(bpb, cluster);
unsigned int root_dir_sectors = FAT::RootDirSize(bpb);
unsigned int fat_size = bpb->FATSz16;
@ -269,140 +328,63 @@ void FAT::readFile(DIR* fileEntry , BiosParameterBlock* bpb){
kterm_put(n & 0x00ff);
kterm_put(n >> 8);
}
kterm_put('\n');
}
void FAT::ListRootDirectoryContents(BiosParameterBlock* bpb){
int total_sectors = bpb->TotSec32;
int fat_size = bpb->FATSz16;
int root_dir_sectors = FAT::RootDirSize(bpb);
int first_data_sector = bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sectors ;
int data_sectors = bpb->TotSec32 - (bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sectors);
int total_clusters = data_sectors / bpb->SecPerClus;
/*
file fsysFatDirectory (const char* DirectoryName){
file file;
unsigned char* buf;
PDIRECTORY directory;
char DosFileName[11];
//ToDosFileName(DirectoryName, DosFileName, 11);
DosFileName[11] =0;
int first_root_dir_sector = first_data_sector - root_dir_sectors;
//int first_sector_of_cluster = ((cluster - 2) * bpb->SecPerClus) + first_data_sector;
uint16_t data[256];
ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, first_root_dir_sector, data);
for (int sector=0; sector <14 ; sector++){
ATAPIO::Read(BUS_PORT::Primary, DEVICE_DRIVE::MASTER, mountInfo.rootOffset + sector, (uint16_t*)buf);
directory = (PDIRECTORY) buf;
auto* RootDirectory = (DIR*)data;
for(int i = 0; i < sizeof(data) / sizeof (DIR); i++)
{
DIR* entry = (DIR*)((uint32_t)RootDirectory + (i * sizeof(DIR)));
for (int i =0; i < 16; i++){
char name[11];
memcpy(name, directory->Filename, 11);
name[11]=0;
if(strncmp(DosFileName, name, 11) == 0){
strcpy(file.name, DirectoryName);
file.id = 0;
file.currentCluster = directory->FirstCluster;
file.eof = 0;
file.filelength = directory->FileSize;
if(directory->Attrib == 0x10){
file.flags = 2;
} else {
file.flags = 1;
}
return file;
}
directory++;
if(entry->Name[0] == FAT::FREE_DIR || entry->Name[0] == FAT::FREE_DIR_2 || entry->Name[0] == 0xE5){
continue;
}
}
// Can't find file
file.flags = -1;
return file;
}
void fsysFATRead(PFILE file, unsigned char* buffer, unsigned int length){
if(file){
unsigned int physSector = 32 + (file->currentCluster - 1);
const unsigned int SECTOR_SIZE = 512;
// read sector
ATA_DEVICE::Read(BUS_PORT::Primary, DEVICE_DRIVE::MASTER, physSector, (uint16_t*) buffer );
if(entry->ATTR & FAT::ATTRIBUTES::ATTR_HIDDEN){
continue;
}
unsigned int FAT_Offset = file->currentCluster + (file->currentCluster /2);
unsigned int FAT_Sector = 1 + (FAT_Offset / SECTOR_SIZE);
unsigned int entryOffset =FAT_Offset % SECTOR_SIZE;
if(entry->ATTR & FAT::ATTRIBUTES::ATTR_SYSTEM)
continue;
uint8_t FAT[SECTOR_SIZE*2];
ATA_DEVICE::Read(BUS_PORT::Primary, DEVICE_DRIVE::MASTER, FAT_Sector,(uint16_t*) FAT); // Read 1st FAT sector
ATA_DEVICE::Read(BUS_PORT::Primary, DEVICE_DRIVE::MASTER, FAT_Sector +1, (uint16_t*)FAT+SECTOR_SIZE);
// read entry for next cluster
uint16_t nextCluster = *(uint16_t*) &FAT[entryOffset];
// test if entry is odd or even
if(file->currentCluster & 0x0001){
nextCluster>>= 4; // grab the high 12 bits
if(entry->ATTR & FAT::ATTRIBUTES::ATTR_VOLUME_ID){
continue;
}
if (!(entry->ATTR & FAT::ATTRIBUTES::ATTR_LONG_NAME)){
for(char n : entry->Name){
if(n == 0x20)
continue;
kterm_put(n);
}
}else{
nextCluster &= 0x0FFF; // grab the low 12 bits
printf("Long file name detected!");
}
// test for end of file
if(nextCluster >= 0xff8){
file->eof -1;
return;
printf(" [Size: %d bytes, Attributes: %d]\n", entry->ATTR, entry->FileSize);
if(entry->ATTR & FAT::ATTRIBUTES::ATTR_DIRECTORY ){
FAT::OpenSubdir(entry, bpb);
} else {
FAT::ReadFileContents(entry, bpb);
}
// test for file corruption
if(nextCluster == 0){
file->eof =1;
return;
}
// set next cluster
file->currentCluster = nextCluster;
}
}
FILE fsysFatOpenSubDir(FILE kFile, const char* filename){
FILE file;
char DosFileName[11];
ToDosFileName(filename, DosFileName, 11);
DosFileName[11] = 0;
while(!kFile.eof){
//read directory
unsigned char buf[512];
fsysFATRead(&file, buf, 512);
PDIRECTORY pkDir = (PDIRECTORY) buf;
for (unsigned int i = 0; i < 16; i++){
// get current filename
char name[11];
memcpy(name, pkDir->Filename, 11);
name[11] = 0;
if(strncmp(name, DosFileName, 11) == 0){
strcpy(file.name, filename);
file.id = 0;
file.currentCluster = pkDir->FirstCluster;
file.filelength = pkDir->FileSize;
file.eof = 0;
// set file type;
if(pkDir->Attrib == 0x10){
file.flags = 2;
} else{
file.flags = 1;
}
return file;
}
// go to next entry
pkDir++;
}
}
// unable to find file
file.flags = -1;
return file;
}
*/

44
kernel/storage/filesystems/FAT/FAT.h
View File

@ -63,32 +63,18 @@ enum struct FAT_TYPE{
class FAT {
public:
// Wanted API for vfs
static file Open(char* filename);
static int close(file* file);
static int Read(file* file, void* buffer , int length);
static int Write(file* file, const void* buffer, int length);
static int create(inode* dir_node, inode** target, const char* component_name);
static int lookup(inode* , inode**, const char*);
static int compare(directoryEntry* , char* , char*);
static superblock* Mount(filesystem* fs, const char* name ,vfsmount* mount);
static FILE Open(char* filename);
static int close(FILE* file);
static int Read(FILE* file, void* buffer , unsigned int length);
static int Write(FILE* file, const void* buffer, unsigned int length);
static int Create(inode* dir_node, inode** target, const char* component_name);
static DirectoryNode* Lookup(inode* , DirectoryNode*);
static int Compare(DirectoryNode* , char *filename, char *filename2);
static FS_SUPER* Mount(filesystem* fs, const char* name , vfsmount* mount);
// TEMP
static void listFilesInRoot(MBR* mbr, BiosParameterBlock* bpb );
static BiosParameterBlock* getBPB( bool DEBUG =false );
static FAT_TYPE determineFATType(BiosParameterBlock* bpb);
static uint16_t GetFATEntry(BiosParameterBlock*, unsigned int);
static uint16_t DetermineFreeSpace();
static int GetSectorOfRootDirectory(BiosParameterBlock*);
static unsigned int RootDirSize(BiosParameterBlock*);
static void OpenSubdir (DIR*, BiosParameterBlock*);
static void readFile(DIR*, BiosParameterBlock*);
static const int FREE = 0x0000;
static const int ALLOCATED = 0x0002;
static const int FREE = 0x0000;
static const int ALLOCATED = 0x0002;
static const int BAD = 0xFFF7;
static const int EOF = 0xFFFF;
@ -98,6 +84,9 @@ public:
static const char DOS_TRAILING_SPACE = 0x20;
static const char FREE_DIR = 0xE5; // If KANJI charset 0x05
static const char FREE_DIR_2 = 0x00; // All directories after this are free including this one
static void ListRootDirectoryContents(BiosParameterBlock* bpb );
static BiosParameterBlock* GetBiosParameterBlock(bool DEBUG =false );
enum ATTRIBUTES {
ATTR_READ_ONLY = 0x01,
@ -111,6 +100,13 @@ public:
private:
static FAT_TYPE DetermineFATType(BiosParameterBlock* bpb);
static uint16_t GetFATEntry(BiosParameterBlock*, unsigned int);
static uint16_t DetermineFreeSpace();
static int GetSectorOfRootDirectory(BiosParameterBlock*);
static unsigned int RootDirSize(BiosParameterBlock*);
static void OpenSubdir (DIR*, BiosParameterBlock*);
static void ReadFileContents(DIR *fileEntry, BiosParameterBlock *bpb);
enum ENTRY_SIZE {
FAT12 = 12,

2
kernel/storage/filesystems/FAT/msdosDate.h
View File

@ -5,6 +5,8 @@
#pragma once
#include "../../../terminal/kterm.h"
#include "../../../memory/KernelHeap.h"
#include "../../../../CoreLib/Memory.h"
// Date Format
// [0..4] Day

94
kernel/storage/vfs/vfs.cpp
View File

@ -14,17 +14,21 @@ int VirtualFileSystem::superblock_number =0;
int VirtualFileSystem::filesystem_number =0;
filesystem* VirtualFileSystem::filesystems[4];
superblock* VirtualFileSystem::superblocks[8];
FS_SUPER* VirtualFileSystem::superblocks[8];
vfsmount* VirtualFileSystem::mounts[12];
void VirtualFileSystem::Mount(filesystem* fs, const char* name)
{
vfsmount* mnt_point = (vfsmount*) malloc(sizeof(vfsmount));
superblock* sb = fs->mount(fs, name, mnt_point);
vfsmount* mnt_point = (vfsmount*) malloc(sizeof(vfsmount));
FS_SUPER* sb = fs->mount(fs, name, mnt_point);
if( sb == nullptr){
printf("mount failed!\n");
return;
}
mounts[mount_number++] = mnt_point;
superblocks[superblock_number++] = sb;
mnt_point->mnt_count = 1;
rootfs = mnt_point;
}
@ -54,64 +58,58 @@ int VirtualFileSystem::register_filesystem(struct filesystem* fs) {
}
struct file* VirtualFileSystem::open(const char* pathname, int flags){
FILE* VirtualFileSystem::open(const char* pathname, int flags){
// 1. Lookup pathname from the root node
// 2. Create a new file descriptor for this v_node if found.
// 2. Create a new file descriptor for this inode if found.
// 3. Create a new file if O_CREATE is specified in the flags.
// See reference material (1) https://man7.org/linux/man-pages/man7/path_resolution.7.html
// FILE file = ->Open(filename);
if(pathname[0] != '/'){
printf("We won't handle relative paths yet!");
file file;
file.flags = 1;
return &file;
}
auto* dentry = rootfs->root;
int result = dentry->op->compare(dentry, "/", dentry->name);
if(result != 0 ){
printf("rootfs not called / \n");
file file;
file.flags = 1;
return &file;
}
FILE* file = (FILE*) malloc(sizeof (FILE)) ;
auto* rootentry = rootfs->root;
char* tokstate = nullptr;
auto nextdir = strtok ((char*)pathname, "/", &tokstate );
while (nextdir)
{
printf("Look for dentry: %s\n", nextdir);
// look to its children
if (dentry->children ) {
printf("No children | children unknown!\n");
break;
}
if (dentry->op->compare(dentry, nextdir, dentry->name))
{
// file found
nextdir = strtok(nullptr, "/", &tokstate);
}
// look up children if not filled
if(rootentry->children == nullptr)
{
rootentry = rootentry->node->lookup(rootentry->node, rootentry);
}
file file;
file.flags = 1;
return &file;
if(rootentry->children == nullptr)
{
file->flags =1;
return file;
}
// let's just loop through the folder first
auto* child = rootentry->children;
while(child->next != nullptr){
auto* directory = (DirectoryNode*)child->data;
if( directory->compare(directory, directory->name, nextdir) == 0){
nextdir = strtok(nullptr, "/", &tokstate);
if(nextdir == NULL){
file->root = directory->node;
file->flags =0;
file->read = FAT::Read;
return file;
}
}
child = child->next;
}
file->flags = 1;
return file;
}
int VirtualFileSystem::close (struct file* file){
int VirtualFileSystem::close (struct FILE* file){
// 1. release the file descriptor
}
int VirtualFileSystem::write(struct file* file, const void* buf, size_t len){
int VirtualFileSystem::write(struct FILE* file, const void* buf, unsigned int len){
// 1. Write len bytes from buf to the opened file.
// 2. return written size or error code if an error occurs
}
int VirtualFileSystem::read (struct file* file, void* buf, size_t len){
int VirtualFileSystem::read (struct FILE* file, void* buf, unsigned int len){
// 1. read min(len, readable file data size) bytes ro buf from the opened file.
// 2. return read size or error code if an error occurs
}

10
kernel/storage/vfs/vfs.h
View File

@ -11,10 +11,10 @@
static int register_filesystem(struct filesystem* fs);
static struct file* open(const char* pathname, int flags);
static int close(struct file* file);
static int write(struct file* file, const void* buf, size_t len);
static int read(struct file* file, void* buf, size_t len);
static FILE* open(const char* pathname, int flags);
static int close(struct FILE* file);
static int write(struct FILE* file, const void* buf, unsigned int len);
static int read(struct FILE* file, void* buf, unsigned int len);
private:
static vfsmount* rootfs;
@ -25,7 +25,7 @@
static int filesystem_number;
static filesystem* filesystems[];
static superblock* superblocks[];
static FS_SUPER* superblocks[];
static vfsmount* mounts[];
};

90
kernel/storage/vfs/vfs_types.h
View File

@ -5,55 +5,52 @@
// grasslab.github.io/osdi/en/labs/lab7.html
#include <stddef.h>
#include <stdint.h>
#include "../../../CoreLib/List.h"
struct inode_operations;
struct vfsmount;
struct superblock;
struct FS_SUPER;
struct inode;
struct dentry_operations;
struct directoryEntry;
struct DirectoryNode;
struct filesystem;
struct superblock;
struct file;
struct FS_SUPER;
struct FILE;
struct file_operations{
int(*write) (file* file, const void* buf, size_t len);
int(*read) (file* file, void* buf, size_t len);
};
struct inode_operations {
int (*create)(inode*, directoryEntry*, const char* );
directoryEntry* (*lookup)(inode* , directoryEntry*);
int (*link)(directoryEntry*, inode* , directoryEntry*);
int (*unlink)(inode*, directoryEntry*);
int (*symlink)(inode*, directoryEntry*);
int (*mkdir)(inode*, directoryEntry*, const char*);
int (*rmdir)(inode*, directoryEntry*);
int (*rename)(inode*, directoryEntry*, inode*, directoryEntry*);
void (*truncate)(inode*);
int (*permission)(inode*, int);
int (*setattr)(directoryEntry, unsigned long*);
int (*getattr)(vfsmount* mnt, directoryEntry*, unsigned long*);
};
// Describes a mount
struct vfsmount {
vfsmount* mnt_parent; // fs we are mounted on
directoryEntry* mountpoint; // dentry of mount point
directoryEntry* root; // root of the mounted tree
superblock* sb; // pointer to the superblock
DirectoryNode* mountpoint; // dentry of mount point
DirectoryNode* root; // root of the mounted tree
FS_SUPER* sb; // pointer to the superblock
unsigned int mnt_count; // keep track of users of this structure
int mnt_flags;
char* mnt_devname; // name of device eg /dev/dsk/hda1
};
struct superblock;
struct FS_SUPER;
// Represents a filesystem object (i.e. a file or directory or device)
struct inode {
unsigned long mode; // access permissions
unsigned long uid; // user id owner
unsigned long gid; // group id owner
unsigned int flags;
inode_operations* i_op; // operations possible on inode
superblock* sb;
// operations possible on inode
int (*create)(inode*, DirectoryNode*, const char* );
DirectoryNode* (*lookup)(inode* , DirectoryNode*);
int (*link)(DirectoryNode*, inode* , DirectoryNode*);
int (*unlink)(inode*, DirectoryNode*);
int (*symlink)(inode*, DirectoryNode*);
int (*mkdir)(inode*, DirectoryNode*, const char*);
int (*rmdir)(inode*, DirectoryNode*);
int (*rename)(inode*, DirectoryNode*, inode*, DirectoryNode*);
void (*truncate)(inode*);
int (*permission)(inode*, int);
int (*setattr)(DirectoryNode, unsigned long*);
int (*getattr)(vfsmount* mnt, DirectoryNode*, unsigned long*);
FS_SUPER* sb;
unsigned long ino; // unique number of this inode
unsigned int links; // number of hard links
void* device;
@ -62,43 +59,39 @@ struct inode {
unsigned long mtime; // Modify time
unsigned long ctime; // Creation time
unsigned short bytes; // bytes consumed
file_operations* fop;
// File operations possible on Inode;
int(*write) (FILE* file, const void* buf, unsigned int len);
int(*read) (FILE* file, void* buf, unsigned int len);
void* internal; // point to underlying representation of this virtual node (e.g. FAT entry or Directory Entry)
};
// Represents the possible operations on a directory entry
struct dentry_operations
{
int (*compare)(directoryEntry*, char*, char* );
int (*o_delete)(directoryEntry*);
void (*release)(directoryEntry*);
void (*iput)(directoryEntry*, inode* );
};
// Represents the name of files in the filesystem
// it identifies the file that an inode represents
struct directoryEntry {
struct DirectoryNode {
char* name; // name of the file on the disk
directoryEntry* parent; // parent of the file
DirectoryNode* parent; // parent of the file
inode* node; // node belongs to...
dentry_operations* op;
directoryEntry* children[];
int (*compare)(DirectoryNode*, char*, char* );
int (*o_delete)(DirectoryNode*);
void (*release)(DirectoryNode*);
void (*iput)(DirectoryNode*, inode*);
List* children;
};
// Represents a filesystem type
struct filesystem {
const char* name;
superblock* (*mount)(filesystem* self, const char* name, vfsmount* mnt);
FS_SUPER* (*mount)(filesystem* self, const char* name, vfsmount* mnt);
};
// Represents a mounted filesystem
struct superblock {
struct FS_SUPER {
void* device; // device associated with the filesystem
unsigned long blocksize;
unsigned long maxbytes;
filesystem* type;
unsigned long magic; // IDK
directoryEntry* root; // Root dentry
DirectoryNode* root; // Root dentry
int count; // IDK
void* fs_info; // pointer to raw filesystem info
dentry_operations* d_op;
@ -106,10 +99,11 @@ struct superblock {
};
// Represents an opened file
struct file {
struct FILE {
inode* root;
size_t f_pos; // The next read/write position of this file descriptor;
file_operations* f_ops;
unsigned int f_pos; // The next read/write position of this file descriptor;
int(*write) (FILE* file, const void* buf, unsigned int len);
int(*read) (FILE* file, void* buf, unsigned int len);
int flags;
};

2
todo.md
View File

@ -4,7 +4,7 @@
This list keeps me focused and organised so I don't forget what
needs to be done. It is a expansion on the features markdown file which describes the features. Here I put things I need to remember
needs to be done. It is a expansion on the features markdown FILE which describes the features. Here I put things I need to remember
to do on a more in depth level.
## --