kernel: finish implementation of private and shared futexes

syscall/dispatch.c

@@ -48,6 +48,8 @@ static const virt_addr_t syscall_table[] = {
 		VM_CONTROLLER_SUPPLY_PAGES,
 		vm_controller_supply_pages),
 	SYSCALL_TABLE_ENTRY(KERN_OBJECT_WAIT, kern_object_wait),
+	SYSCALL_TABLE_ENTRY(FUTEX_WAIT, futex_wait),
+	SYSCALL_TABLE_ENTRY(FUTEX_WAKE, futex_wake),
 };
 static const size_t syscall_table_count
 	= sizeof syscall_table / sizeof syscall_table[0];

syscall/futex.c

@@ -0,0 +1,37 @@
+#include <kernel/futex.h>
+#include <kernel/sched.h>
+#include <kernel/syscall.h>
+#include <kernel/task.h>
+
+kern_status_t sys_futex_wait(
+	kern_futex_t *futex,
+	kern_futex_t new_val,
+	unsigned int flags)
+{
+	struct task *self = current_task();
+	if (!validate_access_r(self, futex, sizeof *futex)) {
+		return KERN_MEMORY_FAULT;
+	}
+
+	futex_key_t key;
+	kern_status_t status = futex_get(futex, &key, flags);
+	if (status != KERN_OK) {
+		return status;
+	}
+
+	return futex_wait(key, new_val, flags);
+}
+
+kern_status_t sys_futex_wake(
+	kern_futex_t *futex,
+	unsigned int nr_waiters,
+	unsigned int flags)
+{
+	futex_key_t key;
+	kern_status_t status = futex_get(futex, &key, flags);
+	if (status != KERN_OK) {
+		return status;
+	}
+
+	return futex_wake(key, nr_waiters, flags);
+}