#pragma once
// ke_dpc.h - deferred procedure calls
//
// DPCs are the kernel's bottom-half mechanism.  Hardware ISRs can queue a DPC
// after acknowledging/capturing device state; the DPC then runs later at
// DISPATCH_LEVEL from the common interrupt-exit path.  DPC routines must not
// wait, block, or call PASSIVE_LEVEL-only code.

#include <stdint.h>
#include <stdbool.h>
#include <ke_list.h>
#include <ke_spinlock.h>

typedef struct KDPC KDPC;

typedef void (*KDEFERRED_ROUTINE)(KDPC* dpc,
                                  void* context,
                                  void* systemArgument1,
                                  void* systemArgument2);

struct KDPC {
    LIST_ENTRY        Link;
    KDEFERRED_ROUTINE Routine;
    void*             Context;
    void*             SystemArgument1;
    void*             SystemArgument2;
    volatile long     Inserted;
};

// Called during kernel bring-up before interrupts are enabled.
void KeInitializeDpcSystem(void);

__declspec(dllexport) void KeInitializeDpc(KDPC* dpc,
                                           KDEFERRED_ROUTINE routine,
                                           void* context);

// Queue a DPC if it is not already queued.  Returns false if the DPC was
// already pending or the arguments are invalid.
__declspec(dllexport) bool KeInsertQueueDpc(KDPC* dpc,
                                            void* systemArgument1,
                                            void* systemArgument2);

// Internal: drain queued DPCs at DISPATCH_LEVEL.  Called from interrupt exit.
void KiDrainDpcQueue(void);