kernel: DPC support

kernel-src/include/kernel/dpc.h

@@ -0,0 +1,22 @@
+#ifndef _DPC_H
+#define _DPC_H
+
+#include <arch/context.h>
+#include <stdbool.h>
+
+typedef void * dpcarg_t;
+typedef void (*dpcfn_t)(context_t *, dpcarg_t);
+
+typedef struct _dpc_t {
+	struct _dpc_t *next;
+	struct _dpc_t *prev;
+	bool enqueued;
+	dpcfn_t fn;
+	dpcarg_t arg;
+} dpc_t;
+
+void dpc_enqueue(dpc_t *dpc, dpcfn_t, dpcarg_t);
+void dpc_dequeue(dpc_t *dpc);
+void dpc_init();
+
+#endif

kernel-src/include/kernel/interrupt.h

@@ -15,6 +15,7 @@
 #define IPL_MAX 0
 #define IPL_TIMER 1
 #define IPL_KEYBOARD 2
+#define IPL_DPC 900
 #define IPL_NORMAL 1000
 
 struct _isr_t;

kernel-src/include/x86-64/arch/cpu.h

@@ -10,6 +10,7 @@
 #include <kernel/vmm.h>
 #include <kernel/timer.h>
 #include <kernel/scheduler.h>
+#include <kernel/dpc.h>
 
 typedef struct cpu_t {
 	thread_t *thread;
@@ -26,6 +27,7 @@ typedef struct cpu_t {
 	timerentry_t schedtimerentry;
 	void *schedulerstack;
 	isr_t *isrqueue;
+	dpc_t *dpcqueue;
 } cpu_t;
 
 #define CPU_HALT() asm volatile("hlt")