LXR qemu/include/hw/virtio/virtio-bus.h

   1/*
   2 * VirtioBus
   3 *
   4 *  Copyright (C) 2012 : GreenSocs Ltd
   5 *      http://www.greensocs.com/ , email: info@greensocs.com
   6 *
   7 *  Developed by :
   8 *  Frederic Konrad   <fred.konrad@greensocs.com>
   9 *
  10 * This program is free software; you can redistribute it and/or modify
  11 * it under the terms of the GNU General Public License as published by
  12 * the Free Software Foundation, either version 2 of the License, or
  13 * (at your option) any later version.
  14 *
  15 * This program is distributed in the hope that it will be useful,
  16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 * GNU General Public License for more details.
  19 *
  20 * You should have received a copy of the GNU General Public License along
  21 * with this program; if not, see <http://www.gnu.org/licenses/>.
  22 *
  23 */
  24
  25#ifndef VIRTIO_BUS_H
  26#define VIRTIO_BUS_H
  27
  28#include "hw/qdev-core.h"
  29#include "hw/virtio/virtio.h"
  30
  31#define TYPE_VIRTIO_BUS "virtio-bus"
  32#define VIRTIO_BUS_GET_CLASS(obj) \
  33        OBJECT_GET_CLASS(VirtioBusClass, obj, TYPE_VIRTIO_BUS)
  34#define VIRTIO_BUS_CLASS(klass) \
  35        OBJECT_CLASS_CHECK(VirtioBusClass, klass, TYPE_VIRTIO_BUS)
  36#define VIRTIO_BUS(obj) OBJECT_CHECK(VirtioBusState, (obj), TYPE_VIRTIO_BUS)
  37
  38typedef struct VirtioBusState VirtioBusState;
  39
  40typedef struct VirtioBusClass {
  41    /* This is what a VirtioBus must implement */
  42    BusClass parent;
  43    void (*notify)(DeviceState *d, uint16_t vector);
  44    void (*save_config)(DeviceState *d, QEMUFile *f);
  45    void (*save_queue)(DeviceState *d, int n, QEMUFile *f);
  46    void (*save_extra_state)(DeviceState *d, QEMUFile *f);
  47    int (*load_config)(DeviceState *d, QEMUFile *f);
  48    int (*load_queue)(DeviceState *d, int n, QEMUFile *f);
  49    int (*load_done)(DeviceState *d, QEMUFile *f);
  50    int (*load_extra_state)(DeviceState *d, QEMUFile *f);
  51    bool (*has_extra_state)(DeviceState *d);
  52    bool (*query_guest_notifiers)(DeviceState *d);
  53    int (*set_guest_notifiers)(DeviceState *d, int nvqs, bool assign);
  54    int (*set_host_notifier_mr)(DeviceState *d, int n,
  55                                MemoryRegion *mr, bool assign);
  56    void (*vmstate_change)(DeviceState *d, bool running);
  57    /*
  58     * Expose the features the transport layer supports before
  59     * the negotiation takes place.
  60     */
  61    void (*pre_plugged)(DeviceState *d, Error **errp);
  62    /*
  63     * transport independent init function.
  64     * This is called by virtio-bus just after the device is plugged.
  65     */
  66    void (*device_plugged)(DeviceState *d, Error **errp);
  67    /*
  68     * transport independent exit function.
  69     * This is called by virtio-bus just before the device is unplugged.
  70     */
  71    void (*device_unplugged)(DeviceState *d);
  72    int (*query_nvectors)(DeviceState *d);
  73    /*
  74     * ioeventfd handling: if the transport implements ioeventfd_assign,
  75     * it must implement ioeventfd_enabled as well.
  76     */
  77    /* Returns true if the ioeventfd is enabled for the device. */
  78    bool (*ioeventfd_enabled)(DeviceState *d);
  79    /*
  80     * Assigns/deassigns the ioeventfd backing for the transport on
  81     * the device for queue number n. Returns an error value on
  82     * failure.
  83     */
  84    int (*ioeventfd_assign)(DeviceState *d, EventNotifier *notifier,
  85                            int n, bool assign);
  86    /*
  87     * Does the transport have variable vring alignment?
  88     * (ie can it ever call virtio_queue_set_align()?)
  89     * Note that changing this will break migration for this transport.
  90     */
  91    bool has_variable_vring_alignment;
  92    AddressSpace *(*get_dma_as)(DeviceState *d);
  93} VirtioBusClass;
  94
  95struct VirtioBusState {
  96    BusState parent_obj;
  97
  98    /*
  99     * Set if ioeventfd has been started.
 100     */
 101    bool ioeventfd_started;
 102
 103    /*
 104     * Set if ioeventfd has been grabbed by vhost.  When ioeventfd
 105     * is grabbed by vhost, we track its started/stopped state (which
 106     * depends in turn on the virtio status register), but do not
 107     * register a handler for the ioeventfd.  When ioeventfd is
 108     * released, if ioeventfd_started is true we finally register
 109     * the handler so that QEMU's device model can use ioeventfd.
 110     */
 111    int ioeventfd_grabbed;
 112};
 113
 114void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp);
 115void virtio_bus_reset(VirtioBusState *bus);
 116void virtio_bus_device_unplugged(VirtIODevice *bus);
 117/* Get the device id of the plugged device. */
 118uint16_t virtio_bus_get_vdev_id(VirtioBusState *bus);
 119/* Get the config_len field of the plugged device. */
 120size_t virtio_bus_get_vdev_config_len(VirtioBusState *bus);
 121/* Get bad features of the plugged device. */
 122uint32_t virtio_bus_get_vdev_bad_features(VirtioBusState *bus);
 123/* Get config of the plugged device. */
 124void virtio_bus_get_vdev_config(VirtioBusState *bus, uint8_t *config);
 125/* Set config of the plugged device. */
 126void virtio_bus_set_vdev_config(VirtioBusState *bus, uint8_t *config);
 127
 128static inline VirtIODevice *virtio_bus_get_device(VirtioBusState *bus)
 129{
 130    BusState *qbus = &bus->parent_obj;
 131    BusChild *kid = QTAILQ_FIRST(&qbus->children);
 132    DeviceState *qdev = kid ? kid->child : NULL;
 133
 134    /* This is used on the data path, the cast is guaranteed
 135     * to succeed by the qdev machinery.
 136     */
 137    return (VirtIODevice *)qdev;
 138}
 139
 140/* Return whether the proxy allows ioeventfd.  */
 141bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus);
 142/* Start the ioeventfd. */
 143int virtio_bus_start_ioeventfd(VirtioBusState *bus);
 144/* Stop the ioeventfd. */
 145void virtio_bus_stop_ioeventfd(VirtioBusState *bus);
 146/* Tell the bus that vhost is grabbing the ioeventfd. */
 147int virtio_bus_grab_ioeventfd(VirtioBusState *bus);
 148/* bus that vhost is not using the ioeventfd anymore. */
 149void virtio_bus_release_ioeventfd(VirtioBusState *bus);
 150/* Switch from/to the generic ioeventfd handler */
 151int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign);
 152/* Tell the bus that the ioeventfd handler is no longer required. */
 153void virtio_bus_cleanup_host_notifier(VirtioBusState *bus, int n);
 154
 155#endif /* VIRTIO_BUS_H */
 156