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#include <kernel/cpu.H>
#include <kernel/cpumgr.H>
#include <kernel/scheduler.H>
#include <kernel/taskmgr.H>
#include <kernel/task.H>
#include <kernel/syscalls.H>
#include <kernel/console.H>
#include <kernel/pagemgr.H>
#include <kernel/usermutex.H>
extern "C"
void kernel_execute_decrementer()
{
Scheduler* s = CpuManager::getCurrentCPU()->scheduler;
s->returnRunnable();
s->setNextRunnable();
// Resync decrementer.
register uint64_t decrementer = 0x0f000000;
asm volatile("mtdec %0" :: "r"(decrementer));
}
namespace Systemcalls
{
typedef void(*syscall)(task_t*);
void TaskYield(task_t*);
void TaskStart(task_t*);
void TaskEnd(task_t*);
void TaskGettid(task_t*);
void MutexCreate(task_t*);
void MutexDestroy(task_t*);
void MutexLockCont(task_t*);
void MutexUnlockCont(task_t*);
syscall syscalls[] =
{
&TaskYield,
&TaskStart,
&TaskEnd,
&TaskGettid,
&MutexCreate,
&MutexDestroy,
&MutexLockCont,
&MutexUnlockCont,
};
};
extern "C"
void kernel_execute_systemcall()
{
using namespace Systemcalls;
task_t* t = TaskManager::getCurrentTask();
uint64_t syscall = t->context.gprs[3];
if (syscall > SYSCALL_MAX)
{
// TODO : kill task.
printk("Invalid syscall : %lld\n", syscall);
while(1);
}
else
{
syscalls[syscall](t);
}
}
#define TASK_GETARGN(t, n) (t->context.gprs[n+4])
#define TASK_GETARG0(t) (TASK_GETARGN(t,0))
#define TASK_GETARG1(t) (TASK_GETARGN(t,1))
#define TASK_GETARG2(t) (TASK_GETARGN(t,2))
#define TASK_GETARG3(t) (TASK_GETARGN(t,3))
#define TASK_GETARG4(t) (TASK_GETARGN(t,4))
#define TASK_GETARG5(t) (TASK_GETARGN(t,5))
#define TASK_GETARG6(t) (TASK_GETARGN(t,6))
#define TASK_GETARG7(t) (TASK_GETARGN(t,7))
#define TASK_SETRTN(t, n) (t->context.gprs[3] = (n))
namespace Systemcalls
{
void TaskYield(task_t* t)
{
Scheduler* s = t->cpu->scheduler;
s->returnRunnable();
s->setNextRunnable();
}
void TaskStart(task_t* t)
{
task_t* newTask =
TaskManager::createTask((TaskManager::task_fn_t)TASK_GETARG0(t),
(void*)TASK_GETARG1(t));
newTask->cpu = t->cpu;
t->cpu->scheduler->addTask(newTask);
TASK_SETRTN(t, newTask->tid);
}
void TaskEnd(task_t* t)
{
// Make sure task pointers are updated before we delete this task.
t->cpu->scheduler->setNextRunnable();
// TODO: Deal with join.
// Clean up task memory.
PageManager::freePage(t->context.stack_ptr, TASK_DEFAULT_STACK_SIZE);
delete t;
}
void TaskGettid(task_t* t)
{
TASK_SETRTN(t, t->tid);
}
void MutexCreate(task_t* t)
{
UserMutex * m = new UserMutex();
TASK_SETRTN(t, (uint64_t)m);
}
void MutexDestroy(task_t* t)
{
// TODO: Extra verification of parameter and mutex state.
delete (UserMutex*) TASK_GETARG0(t);
TASK_SETRTN(t, 0);
}
void MutexLockCont(task_t* t)
{
// TODO: Extra verification of parameter and mutex state.
UserMutex* m = (UserMutex*) TASK_GETARG0(t);
m->lock.lock();
if (m->unlock_pend)
{
// We missed the unlock syscall, take lock and return to userspace.
m->unlock_pend = false;
m->lock.unlock();
}
else
{
// Queue ourself to wait for unlock.
m->waiting.insert(TaskManager::getCurrentTask());
m->lock.unlock();
CpuManager::getCurrentCPU()->scheduler->setNextRunnable();
}
TASK_SETRTN(t, 0);
}
void MutexUnlockCont(task_t* t)
{
// TODO: Extra verification of parameter and mutex state.
UserMutex* m = (UserMutex*) TASK_GETARG0(t);
m->lock.lock();
task_t* wait_task = m->waiting.remove();
if (NULL == wait_task)
{
m->unlock_pend = true;
}
else
{
wait_task->cpu->scheduler->addTask(wait_task);
}
m->lock.unlock();
TASK_SETRTN(t, 0);
}
};
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