PoliEcho/kern
1
0
Fork 0
forked from PoliEcho-holding-org/kern
Code Pull Requests Activity

Began work FAT32 drivers in KBOOT

Browse Source
This commit is contained in:
Tom-on
2025-01-10 11:30:24 +01:00
parent 23ab5d7bfb
commit 295e3d9c18
8 changed files with 220 additions and 27 deletions
Download Patch File Download Diff File Expand all files Collapse all files
boot/stage2/attr.h → boot/stage2/defs.h
+3 -2
View File
@@ -1,9 +1,10 @@
#ifndef ATTR_H
#define ATTR_H
#ifndef _DEFS_H
#define _DEFS_H
#define __packed __attribute__((packed))
#define __naked __attribute__((naked))
#define __section(_sect) __attribute__((section(_sect)))
#define noreturn __attribute__((noreturn))
#define sizeof_array(_a) (sizeof(_a) / sizeof(_a[0]))
#endif
boot/stage2/disk.c
+16 -2
View File
@@ -19,6 +19,20 @@ void readSectors(uint32_t lba, size_t count, void* dst) {
}
}
/* TODO */
void writeSectors(uint32_t lba, size_t count, void* src) {}
void writeSectors(uint32_t lba, size_t count, void* src) {
outb(PIO_PORT + 6, ((lba >> 24) & 0x0f) | 0xe0);
outb(PIO_PORT + 2, count);
outb(PIO_PORT + 3, lba & 0xff);
outb(PIO_PORT + 4, (lba >> 8) & 0xff);
outb(PIO_PORT + 5, (lba >> 16) & 0xff);
outb(PIO_PORT + 7, PIO_CMD_WRITE);
uint16_t* buf = (uint16_t*)src;
for (size_t i = 0; i < count; i++) {
while (inb(PIO_PORT + 7) & (1 << 7)); // Wait until BSY is cleared
for (size_t j = 0; j < SECTOR_SIZE / 2; j++) outw(PIO_PORT, *buf++);
for (uint8_t wait = 0; wait < 4; wait++) inb(PIO_ALT_STATUS);
}
}
boot/stage2/disk.h
+3 -1
View File
@@ -2,7 +2,7 @@
#define DISK_H
#include "stdint.h"
#include "attr.h"
#include "defs.h"
#define SECTOR_SIZE 512
#define PIO_PORT 0x1f0
@@ -14,6 +14,8 @@
#define BOOTABLE 0x80
#define LBA_TO_OFFSET(_a) ((_a) * SECTOR_SIZE)
struct partition {
uint8_t bootable;
uint8_t startCHS[3];
boot/stage2/entry.c
+32 -15
View File
@@ -1,24 +1,46 @@
#include "stdint.h"
#include "fat32.h"
#include "stdio.h"
#include "attr.h"
#include "defs.h"
#include "disk.h"
#include "menu.h"
#include "kbd.h"
noreturn void panic() {
setAttr(0x04);
text(COLS/2, ROWS/2, "[ PANIC ]");
while (1) __asm__ volatile ("cli; hlt");
}
void drawPartitions(struct MBR* mbr, uint8_t sel);
void partitonInfo(struct partition* part);
struct partition* menu(struct MBR* mbr);
__section("entry")
noreturn void main() {
keyboardInit();
struct MBR mbr;
readSectors(0, 1, &mbr);
struct partition* bootpart = menu(&mbr);
setAttr(0x0f);
cls();
showCursor();
if (fat32_init(bootpart) != 0) {
setAttr(0x0c);
printf("Failed to initialize FAT32.");
panic();
}
while (1);
}
struct partition* menu(struct MBR* mbr) {
// Select bootable partition by default
uint8_t selected = 0;
for (size_t i = 0; i < 4; i++) {
if (mbr.partitions[i].bootable != BOOTABLE) continue;
if (mbr->partitions[i].bootable != BOOTABLE) continue;
selected = i;
break;
}
@@ -31,14 +53,14 @@ noreturn void main() {
hline(0, 2, COLS);
setAttr(0x02);
text(COLS / 2, 1, "KBOOT");
drawPartitions(&mbr, selected);
partitonInfo(&mbr.partitions[selected]);
drawPartitions(mbr, selected);
partitonInfo(&mbr->partitions[selected]);
while (1) {
// Check for up/down arrow keys or enter
uint8_t scancode = getScancode();
if (scancode == SC_ENTER) { // Boot selected
if (mbr.partitions[selected].type != 0) break;
if (mbr->partitions[selected].type != 0) break;
// Don't allow booting an unused partition
setAttr(0x4f);
@@ -54,16 +76,11 @@ noreturn void main() {
else if (selected == 4) selected = 0;
// Redraw
drawPartitions(&mbr, selected);
partitonInfo(&mbr.partitions[selected]);
drawPartitions(mbr, selected);
partitonInfo(&mbr->partitions[selected]);
}
setAttr(0x0f);
cls();
showCursor();
printf("Booting from Partition %d...", selected);
while (1);
return &mbr->partitions[selected];
}
void drawPartitions(struct MBR* mbr, uint8_t sel) {
boot/stage2/fat32.c
+33
View File
@@ -0,0 +1,33 @@
#include "stdint.h"
#include "string.h"
#include "disk.h"
#include "fat32.h"
// Local context
struct fat32_ctx ctx;
int fat32_init(struct partition* p) {
readSectors(p->startLBA, 1, &ctx.bpb);
ctx.offsetBase = p->startLBA;
if (ctx.bpb.bytesPerSect != SECTOR_SIZE) return 1;
ctx.offsetFats = ctx.offsetBase + ctx.bpb.reservedSects;
ctx.offsetClusts = ctx.offsetFats + ctx.bpb.fatCount * ctx.bpb.sectsPerFat_32;
return 0;
}
int fat32_open(char* filename, int flags, ...) {
// TODO: flags
//struct fat32_traversed res = fat32_traverse(ctx, filename);
//if (!res.dir) return -1;
}
void fat32_close(void* file) {}
int fat32_read(const void* buf, size_t size, size_t count, void* file) {}
boot/stage2/fat32.h
+124
View File
@@ -0,0 +1,124 @@
#ifndef _FAT32_H
#define _FAT32_H
#include "stdint.h"
#include "defs.h"
#include "disk.h"
// Macros
#define FAT32_PTR(_p) ((struct fat32_ctx*)(_p))
#define FAT32_DIR_PTR(_p) ((struct fat32_fd*)(_p))
#define FAT32_FULL_CLUST(_hi, _lo) (((uint32_t)(_hi) << 16) | (_lo))
#define FAT32_INODE_GEN(_dir, _i) ((_dir) * 100 + (_i))
// Long File Name (LFN)
#define LFN_MAX 20
#define LFN_MAX_CHARS 256
// Attributes
#define FAT32_ATTR_READ_ONLY (1 << 0)
#define FAT32_ATTR_HIDDEN (1 << 1)
#define FAT32_ATTR_SYSTEM (1 << 2)
#define FAT32_ATTR_VOLUME_ID (1 << 3)
#define FAT32_ATTR_DIRECTORY (1 << 4)
#define FAT32_ATTR_ARCHIVE (1 << 5)
#define FAT32_ATTR_LFN \
(FAT32_ATTR_READ_ONLY | FAT32_ATTR_HIDDEN \
FAT32_ATTR_SYSTEM | FAT32_ATTR_VOLUME_ID)
/* On-disk structures */
// FAT32 Bios Parameter Block & Extended BPB
struct fat32_bpb {
uint8_t bootjmp[3];
char oemName[8];
uint16_t bytesPerSect;
uint8_t sectsPerClust;
uint16_t reservedSects;
uint8_t fatCount;
uint16_t rootEntryCount;
uint16_t totalSects_16;
uint8_t mediaType;
uint16_t sectsPerFat_16;
uint16_t sectsPerTrack;
uint16_t headCount;
uint32_t hiddenSects;
uint32_t sectCount_32;
// Extended
uint32_t sectsPerFat_32;
uint16_t flags;
uint16_t fatVersion;
uint32_t rootClust;
uint16_t fsinfoSect;
uint16_t backupBootsect;
uint8_t _reserved[12];
uint8_t driveNum;
uint8_t winNTFlags;
uint8_t signature;
uint32_t volumeID;
char volumeLabel[11];
char systemID[8];
uint8_t bootcode[420];
uint16_t bootsig;
} __packed;
// FAT32 Directory Entry
struct fat32_dentry {
char name[8];
char ext[3];
uint8_t attr;
uint8_t userattr;
char undelete;
uint16_t createTime;
uint16_t createDate;
uint16_t accessDate;
uint16_t clustHigh;
uint16_t modifyTime;
uint16_t modifyDate;
uint16_t clustLow;
uint32_t size;
} __packed;
// FAT32 Long File Name entry
struct fat32_lfn {
uint8_t order;
uint8_t name1[10];
uint8_t attr;
uint8_t type;
uint8_t checksum;
uint8_t name2[12];
uint16_t zero;
uint8_t name3[4];
} __packed;
/* In memory structures */
struct fat32_ctx {
size_t offsetBase;
size_t offsetFats;
size_t offsetClusts;
struct fat32_bpb bpb;
};
struct fat32_fd {
uint32_t ptr;
uint8_t index;
uint32_t dirStart;
uint32_t dirCurrent;
struct fat32_dentry dentry;
};
// Handlers
int fat32_init(struct partition* p);
int fat32_open(char* filename, int flags, ...); /* We won't use the va_args */
void* fat32_fopen(const char* path, const char* mode);
void fat32_fclose(void* file);
int fat32_fgetc(void* file);
char* fat32_fgets(char* s, size_t n, void* file);
int fat32_fread(const void* buf, size_t size, size_t count, void* file);
int fat32_fseek(void* file, size_t offset, int whence);
long fat32_ftell(void* file);
#endif
boot/stage2/kbd.c
+1 -1
View File
@@ -6,7 +6,7 @@
int keyboardInit() { return 0; }
uint8_t getScancode() {
while (inb(PS2_STAT_PORT) & 0x01 == 0);
while ((inb(PS2_STAT_PORT) & 0x01) == 0);
return inb(PS2_DATA_PORT);
}
boot/stage2/stdio.c
+8 -6
View File
@@ -8,9 +8,7 @@ static uint32_t xpos;
static uint32_t ypos;
static uint8_t attr;
void setAttr(uint8_t newattr) {
attr = newattr;
}
void setAttr(uint8_t newattr) { attr = newattr; }
void setCursor(uint32_t row, uint32_t col) {
xpos = col;
@@ -98,7 +96,6 @@ int vsnprintf(void* buf, size_t len, char* fmt, va_list args) {
char pad = ' ';
int width = 0;
// TODO: padding
if (*fmt == '0') pad = '0';
while (*fmt >= '0' && *fmt <= '9') {
width *= 10;
@@ -110,14 +107,19 @@ int vsnprintf(void* buf, size_t len, char* fmt, va_list args) {
switch (*fmt++) {
case 'd': s = itoa(va_arg(args, int), 10); goto string;
case 'x': s = itoa(va_arg(args, int), 16); goto string;
case 's': s = va_arg(args, char*);
string: while (*s != '\0' && pos < len - 1) str[pos++] = *s++; break;
case 's': s = va_arg(args, char*); goto string;
case 'c': if (pos < len - 1) str[pos++] = va_arg(args, char); break;
case '%': if (pos < len - 1) str[pos++] = '%'; break;
default:
if (pos < len - 1) str[pos++] = '%';
if (pos < len - 1) str[pos++] = *(fmt - 1);
break;
string:
width -= strlen(s) - 1;
if (width < 0) width = 0;
while (width-- && pos < len - 1) str[pos++] = pad;
while (*s && pos < len - 1) str[pos++] = *s++;
break;
}
}