banan-os/kernel/kernel/Thread.cpp

128 lines
3.7 KiB
C++

#include <BAN/Errors.h>
#include <kernel/CriticalScope.h>
#include <kernel/InterruptController.h>
#include <kernel/Memory/kmalloc.h>
#include <kernel/Process.h>
#include <kernel/Scheduler.h>
#include <kernel/Thread.h>
namespace Kernel
{
extern "C" void thread_userspace_trampoline(uint64_t rsp, uint64_t rip, int argc, char** argv);
template<size_t size, typename T>
static void write_to_stack(uintptr_t& rsp, const T& value)
{
rsp -= size;
memcpy((void*)rsp, (void*)&value, size);
}
static pid_t s_next_tid = 1;
BAN::ErrorOr<Thread*> Thread::create(entry_t entry, void* data, Process* process)
{
// Create the thread object
Thread* thread = new Thread(s_next_tid++, process);
if (thread == nullptr)
return BAN::Error::from_errno(ENOMEM);
// Initialize stack and registers
thread->m_stack_base = (vaddr_t)kmalloc(m_kernel_stack_size, PAGE_SIZE);
if (thread->m_stack_base == 0)
return BAN::Error::from_errno(ENOMEM);
thread->m_rsp = (uintptr_t)thread->m_stack_base + m_kernel_stack_size;
thread->m_rip = (uintptr_t)entry;
// Initialize stack for returning
write_to_stack<sizeof(void*)>(thread->m_rsp, thread);
write_to_stack<sizeof(void*)>(thread->m_rsp, &Thread::on_exit);
write_to_stack<sizeof(void*)>(thread->m_rsp, data);
return thread;
}
BAN::ErrorOr<Thread*> Thread::create_userspace(uintptr_t entry, Process* process, int argc, char** argv)
{
// Create the thread object
Thread* thread = new Thread(s_next_tid++, process);
if (thread == nullptr)
return BAN::Error::from_errno(ENOMEM);
thread->m_is_userspace = true;
// Allocate stack
thread->m_stack_base = (uintptr_t)kmalloc(m_userspace_stack_size, PAGE_SIZE);
ASSERT(thread->m_stack_base);
process->mmu().identity_map_range(thread->m_stack_base, m_userspace_stack_size, MMU::Flags::UserSupervisor | MMU::Flags::ReadWrite | MMU::Flags::Present);
// Allocate interrupt stack
thread->m_interrupt_stack = (vaddr_t)kmalloc(m_interrupt_stack_size, PAGE_SIZE);
ASSERT(thread->m_interrupt_stack);
thread->m_userspace_entry = { .entry = entry, .argc = argc, .argv = argv };
// Setup registers and entry
static entry_t entry_trampoline(
[](void*)
{
userspace_entry_t& entry = Thread::current().m_userspace_entry;
thread_userspace_trampoline(Thread::current().rsp(), entry.entry, entry.argc, entry.argv);
ASSERT_NOT_REACHED();
}
);
thread->m_rsp = thread->m_stack_base + m_userspace_stack_size;
thread->m_rip = (uintptr_t)entry_trampoline;
// Setup stack for returning
write_to_stack<sizeof(void*)>(thread->m_rsp, thread);
write_to_stack<sizeof(void*)>(thread->m_rsp, &Thread::on_exit);
write_to_stack<sizeof(void*)>(thread->m_rsp, nullptr);
return thread;
}
Thread::Thread(pid_t tid, Process* process)
: m_tid(tid), m_process(process)
{}
Thread& Thread::current()
{
return Scheduler::get().current_thread();
}
Process& Thread::process()
{
ASSERT(m_process);
return *m_process;
}
Thread::~Thread()
{
dprintln("thread {} ({}) exit", tid(), m_process->pid());
if (m_interrupt_stack)
kfree((void*)m_interrupt_stack);
kfree((void*)m_stack_base);
}
void Thread::validate_stack() const
{
if (stack_base() <= m_rsp && m_rsp <= stack_base() + stack_size())
return;
if (interrupt_stack_base() <= m_rsp && m_rsp <= interrupt_stack_base() + interrupt_stack_size())
return;
Kernel::panic("rsp {8H}, stack {8H}->{8H}, interrupt_stack {8H}->{8H}", m_rsp,
stack_base(), stack_base() + stack_size(),
interrupt_stack_base(), interrupt_stack_base() + interrupt_stack_size()
);
}
void Thread::on_exit()
{
if (m_process)
m_process->on_thread_exit(*this);
Scheduler::get().set_current_thread_done();
ASSERT_NOT_REACHED();
}
}