Files
jsix_import/src/kernel/process.cpp
2019-03-09 12:18:21 -08:00

178 lines
3.4 KiB
C++

#include "cpu.h"
#include "log.h"
#include "process.h"
#include "scheduler.h"
pid_t
process::fork(uintptr_t in_rsp)
{
auto &sched = scheduler::get();
auto *child = sched.create_process();
kassert(child, "process::fork() got null child");
child->ppid = pid;
child->flags =
process_flags::running |
process_flags::ready;
sched.m_runlists[child->priority].push_back(child);
child->rsp = in_rsp;
child->pml4 = page_manager::get()->copy_table(pml4);
kassert(child->pml4, "process::fork() got null pml4");
child->setup_kernel_stack(kernel_stack_size, kernel_stack);
child->rsp = child->kernel_stack + (in_rsp - kernel_stack);
log::debug(logs::task, "Copied process %d to %d, new PML4 %016lx.",
pid, child->pid, child->pml4);
log::debug(logs::task, " copied stack %016lx to %016lx, rsp %016lx to %016lx.",
kernel_stack, child->kernel_stack, in_rsp, child->rsp);
// Add in the faked fork return value
cpu_state *regs = reinterpret_cast<cpu_state *>(child->rsp);
regs->rax = 0;
return child->pid;
}
void *
process::setup_kernel_stack(size_t size, uintptr_t orig)
{
void *stack0 = kutil::malloc(size);
if (orig)
kutil::memcpy(stack0, reinterpret_cast<void*>(orig), size);
else
kutil::memset(stack0, 0, size);
kernel_stack_size = size;
kernel_stack = reinterpret_cast<uintptr_t>(stack0);
return stack0;
}
bool
process::wait_on_signal(uint64_t sigmask)
{
waiting = process_wait::signal;
waiting_info = sigmask;
flags -= process_flags::ready;
return true;
}
bool
process::wait_on_child(uint32_t pid)
{
waiting = process_wait::child;
waiting_info = pid;
flags -= process_flags::ready;
return true;
}
bool
process::wait_on_time(uint64_t time)
{
waiting = process_wait::time;
waiting_info = time;
flags -= process_flags::ready;
return true;
}
bool
process::wait_on_send(uint32_t target_id)
{
scheduler &s = scheduler::get();
process *target = s.get_process_by_id(target_id);
if (!target) return false;
if (!target->wake_on_receive(this)) {
waiting = process_wait::send;
waiting_info = target_id;
flags -= process_flags::ready;
}
return true;
}
bool
process::wait_on_receive(uint32_t source_id)
{
scheduler &s = scheduler::get();
process *source = s.get_process_by_id(source_id);
if (!source) return false;
if (!source->wake_on_send(this)) {
waiting = process_wait::receive;
waiting_info = source_id;
flags -= process_flags::ready;
return true;
}
return false;
}
bool
process::wake_on_signal(int signal)
{
if (waiting != process_wait::signal ||
(waiting_info & (1 << signal)) == 0)
return false;
waiting = process_wait::none;
flags += process_flags::ready;
return true;
}
bool
process::wake_on_child(process *child)
{
if (waiting != process_wait::child ||
(waiting_info && waiting_info != child->pid))
return false;
waiting = process_wait::none;
flags += process_flags::ready;
return true;
}
bool
process::wake_on_time(uint64_t now)
{
if (waiting != process_wait::time ||
waiting_info > now)
return false;
waiting = process_wait::none;
flags += process_flags::ready;
return true;
}
bool
process::wake_on_send(process *target)
{
if (waiting != process_wait::send ||
waiting_info != target->pid)
return false;
waiting = process_wait::none;
flags += process_flags::ready;
return true;
}
bool
process::wake_on_receive(process *source)
{
if (waiting != process_wait::receive ||
waiting_info != source->pid)
return false;
waiting = process_wait::none;
flags += process_flags::ready;
return true;
}