toaruos/modules/dospart.c

131 lines
3.6 KiB
C

/* vim: tabstop=4 shiftwidth=4 noexpandtab
* This file is part of ToaruOS and is released under the terms
* of the NCSA / University of Illinois License - see LICENSE.md
* Copyright (C) 2014-2018 K. Lange
*/
#include <kernel/system.h>
#include <kernel/logging.h>
#include <kernel/module.h>
#include <kernel/printf.h>
#include <kernel/ata.h>
#define SECTORSIZE 512
static mbr_t mbr;
struct dos_partition_entry {
fs_node_t * device;
partition_t partition;
};
static uint32_t read_part(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
struct dos_partition_entry * device = (struct dos_partition_entry *)node->device;
if (offset > device->partition.sector_count * SECTORSIZE) {
debug_print(WARNING, "Read beyond partition!");
return 0;
}
if (offset + size > device->partition.sector_count * SECTORSIZE) {
size = device->partition.sector_count * SECTORSIZE - offset;
debug_print(WARNING, "Tried to read past end of partition, clamped to %d", size);
}
return read_fs(device->device, offset + device->partition.lba_first_sector * SECTORSIZE, size, buffer);
}
static uint32_t write_part(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
struct dos_partition_entry * device = (struct dos_partition_entry *)node->device;
if (offset > device->partition.sector_count * SECTORSIZE) {
return 0;
}
if (offset + size > device->partition.sector_count * SECTORSIZE) {
size = device->partition.sector_count * SECTORSIZE - offset;
}
return write_fs(device->device, offset + device->partition.lba_first_sector * SECTORSIZE, size, buffer);
}
static void open_part(fs_node_t * node, unsigned int flags) {
return;
}
static void close_part(fs_node_t * node) {
return;
}
static fs_node_t * dospart_device_create(int i, fs_node_t * dev, partition_t * part) {
vfs_lock(dev);
struct dos_partition_entry * device = malloc(sizeof(struct dos_partition_entry));
memcpy(&device->partition, part, sizeof(partition_t));
device->device = dev;
fs_node_t * fnode = malloc(sizeof(fs_node_t));
memset(fnode, 0x00, sizeof(fs_node_t));
fnode->inode = 0;
sprintf(fnode->name, "dospart%d", i);
fnode->device = device;
fnode->uid = 0;
fnode->gid = 0;
fnode->mask = 0660;
fnode->length = device->partition.sector_count * SECTORSIZE; /* TODO */
fnode->flags = FS_BLOCKDEVICE;
fnode->read = read_part;
fnode->write = write_part;
fnode->open = open_part;
fnode->close = close_part;
fnode->readdir = NULL;
fnode->finddir = NULL;
fnode->ioctl = NULL; /* TODO, identify, etc? */
return fnode;
}
static int read_partition_map(char * name) {
fs_node_t * device = kopen(name, 0);
if (!device) return 1;
read_fs(device, 0, SECTORSIZE, (uint8_t *)&mbr);
if (mbr.signature[0] == 0x55 && mbr.signature[1] == 0xAA) {
debug_print(INFO, "Partition table found.");
for (int i = 0; i < 4; ++i) {
if (mbr.partitions[i].status & 0x80) {
debug_print(NOTICE, "Partition #%d: @%d+%d", i+1, mbr.partitions[i].lba_first_sector, mbr.partitions[i].sector_count);
fs_node_t * node = dospart_device_create(i, device, &mbr.partitions[i]);
char tmp[64];
sprintf(tmp, "%s%d", name, i);
vfs_mount(tmp, node);
} else {
debug_print(NOTICE, "Partition #%d: inactive", i+1);
}
}
} else {
debug_print(NOTICE, "No partition table on %s", name);
}
return 0;
}
static int dospart_initialize(void) {
for (char l = 'a'; l < 'z'; ++l) {
char name[64];
sprintf(name, "/dev/hd%c", l);
if (read_partition_map(name)) {
break;
}
}
return 0;
}
static int dospart_finalize(void) {
return 0;
}
MODULE_DEF(dospart, dospart_initialize, dospart_finalize);