RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-22 19:45:08 +00:00
Code Issues Activity Actions

Kernel: Implement MBR partition loader (#168)

Browse source 
This implements a basic MBR partition loader, which removes the reliance
on a hard-coded filesystem offset in the stage2 init.
This commit is contained in:
Conrad Pankoff 2019-06-02 22:57:44 +10:00 • committed by Andreas Kling
parent 466a817950
commit c02b8b715d
4 changed files with 133 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

33
Kernel/init.cpp
View file

@ -6,6 +6,7 @@
#include "Process.h"
#include "PIC.h"
#include <Kernel/Devices/IDEDiskDevice.h>
#include <Kernel/Devices/MBRPartitionTable.h>
#include <Kernel/Devices/DiskPartition.h>
#include "KSyms.h"
#include <Kernel/Devices/NullDevice.h>
@ -58,11 +59,6 @@ VFS* vfs;
}
#endif
// TODO: delete this magic number. this block offset corresponds to a
// partition that starts at 32k into an MBR disk. this value is also specified
// in sync.sh, but should ideally be read from the MBR header at startup.
#define PARTITION_OFFSET 62
[[noreturn]] static void init_stage2()
{
Syscall::initialize();
@ -71,10 +67,29 @@ VFS* vfs;
auto dev_full = make<FullDevice>();
auto dev_random = make<RandomDevice>();
auto dev_ptmx = make<PTYMultiplexer>();
// TODO: decide what drive/partition to use based on cmdline from
// bootloader. currently hardcoded to the equivalent of hd0,1.
auto dev_hd0 = IDEDiskDevice::create();
auto dev_hd0p1 = DiskPartition::create(dev_hd0.copy_ref(), PARTITION_OFFSET);
auto e2fs = Ext2FS::create(dev_hd0p1.copy_ref());
e2fs->initialize();
MBRPartitionTable dev_hd0pt(dev_hd0.copy_ref());
if (!dev_hd0pt.initialize()) {
kprintf("init_stage2: couldn't read MBR from disk");
hang();
}
auto dev_hd0p1 = dev_hd0pt.partition(1);
if (!dev_hd0p1) {
kprintf("init_stage2: couldn't get first partition");
hang();
}
auto e2fs = Ext2FS::create(*dev_hd0p1.copy_ref());
if (!e2fs->initialize()) {
kprintf("init_stage2: couldn't open root filesystem");
hang();
}
vfs->mount_root(e2fs.copy_ref());
@ -89,7 +104,7 @@ VFS* vfs;
auto* system_server_process = Process::create_user_process("/bin/SystemServer", (uid_t)100, (gid_t)100, (pid_t)0, error, { }, { }, tty0);
if (error != 0) {
dbgprintf("error spawning SystemServer: %d\n", error);
dbgprintf("init_stage2: error spawning SystemServer: %d\n", error);
hang();
}
system_server_process->set_priority(Process::HighPriority);