LXR linux/arch/um/include/shared/irq

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
   4 */
   5
   6#ifndef __IRQ_KERN_H__
   7#define __IRQ_KERN_H__
   8
   9#include <linux/interrupt.h>
  10#include <linux/time-internal.h>
  11#include <asm/ptrace.h>
  12#include "irq_user.h"
  13
  14#define UM_IRQ_ALLOC    -1
  15
  16int um_request_irq(int irq, int fd, enum um_irq_type type,
  17                   irq_handler_t handler, unsigned long irqflags,
  18                   const char *devname, void *dev_id);
  19
  20#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
  21/**
  22 * um_request_irq_tt - request an IRQ with timetravel handler
  23 *
  24 * @irq: the IRQ number, or %UM_IRQ_ALLOC
  25 * @fd: The file descriptor to request an IRQ for
  26 * @type: read or write
  27 * @handler: the (generic style) IRQ handler
  28 * @irqflags: Linux IRQ flags
  29 * @devname: name for this to show
  30 * @dev_id: data pointer to pass to the IRQ handler
  31 * @timetravel_handler: the timetravel interrupt handler, invoked with the IRQ
  32 *      number, fd, dev_id and time-travel event pointer.
  33 *
  34 * Returns: The interrupt number assigned or a negative error.
  35 *
  36 * Note that the timetravel handler is invoked only if the time_travel_mode is
  37 * %TT_MODE_EXTERNAL, and then it is invoked even while the system is suspended!
  38 * This function must call time_travel_add_irq_event() for the event passed with
  39 * an appropriate delay, before sending an ACK on the socket it was invoked for.
  40 *
  41 * If this was called while the system is suspended, then adding the event will
  42 * cause the system to resume.
  43 *
  44 * Since this function will almost certainly have to handle the FD's condition,
  45 * a read will consume the message, and after that it is up to the code using
  46 * it to pass such a message to the @handler in whichever way it can.
  47 *
  48 * If time_travel_mode is not %TT_MODE_EXTERNAL the @timetravel_handler will
  49 * not be invoked at all and the @handler must handle the FD becoming
  50 * readable (or writable) instead. Use um_irq_timetravel_handler_used() to
  51 * distinguish these cases.
  52 *
  53 * See virtio_uml.c for an example.
  54 */
  55int um_request_irq_tt(int irq, int fd, enum um_irq_type type,
  56                      irq_handler_t handler, unsigned long irqflags,
  57                      const char *devname, void *dev_id,
  58                      void (*timetravel_handler)(int, int, void *,
  59                                                 struct time_travel_event *));
  60#else
  61static inline
  62int um_request_irq_tt(int irq, int fd, enum um_irq_type type,
  63                      irq_handler_t handler, unsigned long irqflags,
  64                      const char *devname, void *dev_id,
  65                      void (*timetravel_handler)(int, int, void *,
  66                                                 struct time_travel_event *))
  67{
  68        return um_request_irq(irq, fd, type, handler, irqflags,
  69                              devname, dev_id);
  70}
  71#endif
  72
  73static inline bool um_irq_timetravel_handler_used(void)
  74{
  75        return time_travel_mode == TT_MODE_EXTERNAL;
  76}
  77
  78void um_free_irq(int irq, void *dev_id);
  79void free_irqs(void);
  80#endif
  81