Added initrd driver

This commit is contained in:
Marco Cetica 2021-02-05 13:05:05 +01:00
parent dd48ba577d
commit f263f3f481
5 changed files with 113 additions and 10 deletions

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@ -1,5 +1,5 @@
OBJS = tty.o gdt.o idt.o isr.o timer.o keyboard.o \
fs.o cpuid.o
fs.o cpuid.o initrd.o
CC = i686-elf-gcc # cross-compiler
CFLAGS = -m32 -fno-stack-protector -DDEFAULT_USER=root -DDEFAULT_HOSTNAME=vulcan -ffreestanding -Wall -Wextra -Werror -g -c

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@ -1,26 +1,79 @@
#include "initrd.h"
// Private API to IO operations on dir and files
static uint32_t initrd_read(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer);
static struct dirent *initrd_readdir(fs_node_t *node, uint32_t index);
static fs_node_t *initrd_finddir(fs_node_t *node, uint8_t *name);
// Declare various things
initrd_header_t *initrd_header; // Header
initrd_file_header_t *file_header; // List of headers
initrd_file_header_t *file_headers; // List of headers
fs_node_t *initrd_root; // Directory root node
fs_node_t *initrd_dev; // Directory dev node(/dev)
fs_node_t *root_nodes; // List of file nodes
uint32_t nroot_nodes;
uint32_t nroot_nodes; // Number of file nodes
struct dirent dirent;
fs_node_t *init_ramdisk(uint32_t multiboot_location) {
// Initialize main and file headers
initrd_header = (initrd_header_t*)multiboot_location;
file_header = (initrd_file_header_t*)(multiboot_location+sizeof(initrd_header_t));
file_headers = (initrd_file_header_t*)(multiboot_location+sizeof(initrd_header_t));
// Initialize root directory
initrd_root = (fs_node_t*)
initrd_root = (fs_node_t*)kmalloc(sizeof(fs_node_t));
strcpy(initrd_root->name, "initrd");
initrd_root->mask = initrd_root->uid = initrd_root->gid = initrd_root->inode = initrd_root->length = 0;
initrd_root->flags = FS_DIRECTORY;
initrd_root->read = 0;
initrd_root->write = 0;
initrd_root->open = 0;
initrd_root->close = 0;
initrd_root->readdir = &initrd_readdir;
initrd_root->finddir = &initrd_finddir;
initrd_root->ptr = 0;
initrd_root->impl = 0;
// Initialize the /dev/ directory
initrd_dev = (fs_node_t*)kmalloc(sizeof(fs_node_t));
strcpy(initrd_root->name, "dev");
initrd_root->mask = initrd_root->uid = initrd_root->gid = initrd_root->inode = initrd_root->length = 0;
initrd_root->flags = FS_DIRECTORY;
initrd_root->read = 0;
initrd_root->write = 0;
initrd_root->open = 0;
initrd_root->close = 0;
initrd_root->readdir = &initrd_readdir;
initrd_root->finddir = &initrd_finddir;
initrd_root->ptr = 0;
initrd_root->impl = 0;
// Add dev and root directories to the ramdisk
// Let us first allocate space for them
root_nodes = (fs_node_t*)kmalloc(sizeof(fs_node_t) *initrd_header->nfiles);
nroot_nodes = initrd_header->nfiles;
// and then, add each file to an inode
for(uint32_t i = 0; i < initrd_header->nfiles; i++) {
file_headers[i].offset += multiboot_location;
// Create an inode for the file
strcpy(root_nodes[i].name, &file_headers[i].name);
root_nodes[i].mask = root_nodes[i].uid = root_nodes[i].gid = 0;
root_nodes[i].length = file_headers[i].length;
root_nodes[i].inode = i;
root_nodes[i].flags = FS_FILE;
root_nodes[i].read = &initrd_read;
root_nodes[i].write = 0;
root_nodes[i].readdir = 0;
root_nodes[i].finddir = 0;
root_nodes[i].open = 0;
root_nodes[i].close = 0;
root_nodes[i].impl = 0;
}
return initrd_root;
}
static uint32_t initrd_read(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
initrd_file_header_t header = file_header[node->inode];
initrd_file_header_t header = file_headers[node->inode];
if(offset > header.length)
return 0;
if(offset+size > header.length)

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@ -13,6 +13,7 @@
#include <stdint.h>
#include "../libc/string.h"
#include "../mem/kheap.h"
#include "fs.h"
typedef struct {
@ -29,8 +30,5 @@ typedef struct {
// Function to initialize initrd, we'll pass the multiboot
// module as parameter
fs_node_t *init_ramdisk(uint32_t multiboot_location);
static uint32_t initrd_read(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer);
static struct dirent *initrd_readdir(fs_node_t *node, uint32_t index);
static fs_node_t *initrd_finddir(fs_node_t *node, uint8_t *name);
#endif

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@ -10,6 +10,7 @@
#include "drivers/idt.h"
#include "drivers/timer.h"
#include "drivers/keyboard.h"
#include "drivers/initrd.h"
#include "mem/paging.h"
#include "mem/kheap.h"
#include "mem/multiboot.h"
@ -23,8 +24,22 @@
#define PRTAT printf("\n["); printf_color(" ** ", LIGHT_BROWN, BLACK); printf("]"); // Ugly hack to print "[ * ]"
#define PRTER printf("\n["); printf_color(" ERR ", LIGHT_RED, BLACK); printf("]"); // Ugly hack to print "[ ER ]"
uint32_t initrd_setup( struct multiboot *mboot_ptr) {
if(mboot_ptr->mods_count < 0) { // Assert that initrd image is available
PRTER
puts(" - initrd not found!");
PANIC("Cannot find initrd");
}
void kernel_main(unsigned long magic, uint32_t addr) {
extern uint32_t placement_addr;
uint32_t initrd_location = *((uint32_t*)mboot_ptr->mods_addr);
uint32_t initrd_end = *(uint32_t*)(mboot_ptr->mods_addr+4);
placement_addr = initrd_end;
return initrd_location;
}
void kernel_main(unsigned long magic, uint32_t addr, struct multiboot *mboot_ptr) {
// First of all, check if we're booted by a Multiboot-compliant boot loader
if(magic != MULTIBOOT2_BOOTLOADER_MAGIC) {
PRTER
@ -57,10 +72,17 @@ void kernel_main(unsigned long magic, uint32_t addr) {
PRTOK
printf(" - Loaded PS/2 driver");
uint32_t loc = initrd_setup(mboot_ptr); // Setup initial ramdisk
init_paging(); // Initialize paging
PRTOK
printf(" - Loaded Paging");
// Now we can start initrd
fs_root = init_ramdisk(loc);
PRTOK
printf(" - Loaded Initrd");
PRTAT
printf(" - Testing heap...\t");

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@ -94,6 +94,36 @@ typedef unsigned short multiboot_uint16_t;
typedef unsigned int multiboot_uint32_t;
typedef unsigned long long multiboot_uint64_t;
struct multiboot
{
multiboot_uint32_t flags;
multiboot_uint32_t mem_lower;
multiboot_uint32_t mem_upper;
multiboot_uint32_t boot_device;
multiboot_uint32_t cmdline;
int32_t mods_count;
multiboot_uint32_t mods_addr;
multiboot_uint32_t num;
multiboot_uint32_t size;
multiboot_uint32_t addr;
multiboot_uint32_t shndx;
multiboot_uint32_t mmap_length;
multiboot_uint32_t mmap_addr;
multiboot_uint32_t drives_length;
multiboot_uint32_t drives_addr;
multiboot_uint32_t config_table;
multiboot_uint32_t boot_loader_name;
multiboot_uint32_t apm_table;
multiboot_uint32_t vbe_control_info;
multiboot_uint32_t vbe_mode_info;
multiboot_uint32_t vbe_mode;
multiboot_uint32_t vbe_interface_seg;
multiboot_uint32_t vbe_interface_off;
multiboot_uint32_t vbe_interface_len;
} __attribute__((packed));
typedef struct multiboot_header multiboot_header_t;
struct multiboot_header
{
/* Must be MULTIBOOT_MAGIC - see above. */