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.h" 29 #include "sysemu/sysemu.h" 30 #include "hw/virtio/virtio.h" 31 32 #define TYPE_VIRTIO_BUS "virtio-bus" 33 #define VIRTIO_BUS_GET_CLASS(obj) \ 34 OBJECT_GET_CLASS(VirtioBusClass, obj, TYPE_VIRTIO_BUS) 35 #define VIRTIO_BUS_CLASS(klass) \ 36 OBJECT_CLASS_CHECK(VirtioBusClass, klass, TYPE_VIRTIO_BUS) 37 #define VIRTIO_BUS(obj) OBJECT_CHECK(VirtioBusState, (obj), TYPE_VIRTIO_BUS) 38 39 typedef struct VirtioBusState VirtioBusState; 40 41 typedef struct VirtioBusClass { 42 /* This is what a VirtioBus must implement */ 43 BusClass parent; 44 void (*notify)(DeviceState *d, uint16_t vector); 45 void (*save_config)(DeviceState *d, QEMUFile *f); 46 void (*save_queue)(DeviceState *d, int n, QEMUFile *f); 47 void (*save_extra_state)(DeviceState *d, QEMUFile *f); 48 int (*load_config)(DeviceState *d, QEMUFile *f); 49 int (*load_queue)(DeviceState *d, int n, QEMUFile *f); 50 int (*load_done)(DeviceState *d, QEMUFile *f); 51 int (*load_extra_state)(DeviceState *d, QEMUFile *f); 52 bool (*has_extra_state)(DeviceState *d); 53 bool (*query_guest_notifiers)(DeviceState *d); 54 int (*set_guest_notifiers)(DeviceState *d, int nvqs, bool assign); 55 void (*vmstate_change)(DeviceState *d, bool running); 56 /* 57 * Expose the features the transport layer supports before 58 * the negotiation takes place. 59 */ 60 void (*pre_plugged)(DeviceState *d, Error **errp); 61 /* 62 * transport independent init function. 63 * This is called by virtio-bus just after the device is plugged. 64 */ 65 void (*device_plugged)(DeviceState *d, Error **errp); 66 /* 67 * transport independent exit function. 68 * This is called by virtio-bus just before the device is unplugged. 69 */ 70 void (*device_unplugged)(DeviceState *d); 71 int (*query_nvectors)(DeviceState *d); 72 /* 73 * ioeventfd handling: if the transport implements ioeventfd_assign, 74 * it must implement ioeventfd_enabled as well. 75 */ 76 /* Returns true if the ioeventfd is enabled for the device. */ 77 bool (*ioeventfd_enabled)(DeviceState *d); 78 /* 79 * Assigns/deassigns the ioeventfd backing for the transport on 80 * the device for queue number n. Returns an error value on 81 * failure. 82 */ 83 int (*ioeventfd_assign)(DeviceState *d, EventNotifier *notifier, 84 int n, bool assign); 85 /* 86 * Does the transport have variable vring alignment? 87 * (ie can it ever call virtio_queue_set_align()?) 88 * Note that changing this will break migration for this transport. 89 */ 90 bool has_variable_vring_alignment; 91 AddressSpace *(*get_dma_as)(DeviceState *d); 92 } VirtioBusClass; 93 94 struct VirtioBusState { 95 BusState parent_obj; 96 97 /* 98 * Set if ioeventfd has been started. 99 */ 100 bool ioeventfd_started; 101 102 /* 103 * Set if ioeventfd has been grabbed by vhost. When ioeventfd 104 * is grabbed by vhost, we track its started/stopped state (which 105 * depends in turn on the virtio status register), but do not 106 * register a handler for the ioeventfd. When ioeventfd is 107 * released, if ioeventfd_started is true we finally register 108 * the handler so that QEMU's device model can use ioeventfd. 109 */ 110 int ioeventfd_grabbed; 111 }; 112 113 void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp); 114 void virtio_bus_reset(VirtioBusState *bus); 115 void virtio_bus_device_unplugged(VirtIODevice *bus); 116 /* Get the device id of the plugged device. */ 117 uint16_t virtio_bus_get_vdev_id(VirtioBusState *bus); 118 /* Get the config_len field of the plugged device. */ 119 size_t virtio_bus_get_vdev_config_len(VirtioBusState *bus); 120 /* Get bad features of the plugged device. */ 121 uint32_t virtio_bus_get_vdev_bad_features(VirtioBusState *bus); 122 /* Get config of the plugged device. */ 123 void virtio_bus_get_vdev_config(VirtioBusState *bus, uint8_t *config); 124 /* Set config of the plugged device. */ 125 void virtio_bus_set_vdev_config(VirtioBusState *bus, uint8_t *config); 126 127 static inline VirtIODevice *virtio_bus_get_device(VirtioBusState *bus) 128 { 129 BusState *qbus = &bus->parent_obj; 130 BusChild *kid = QTAILQ_FIRST(&qbus->children); 131 DeviceState *qdev = kid ? kid->child : NULL; 132 133 /* This is used on the data path, the cast is guaranteed 134 * to succeed by the qdev machinery. 135 */ 136 return (VirtIODevice *)qdev; 137 } 138 139 /* Return whether the proxy allows ioeventfd. */ 140 bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus); 141 /* Start the ioeventfd. */ 142 int virtio_bus_start_ioeventfd(VirtioBusState *bus); 143 /* Stop the ioeventfd. */ 144 void virtio_bus_stop_ioeventfd(VirtioBusState *bus); 145 /* Tell the bus that vhost is grabbing the ioeventfd. */ 146 int virtio_bus_grab_ioeventfd(VirtioBusState *bus); 147 /* bus that vhost is not using the ioeventfd anymore. */ 148 void virtio_bus_release_ioeventfd(VirtioBusState *bus); 149 /* Switch from/to the generic ioeventfd handler */ 150 int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign); 151 /* Tell the bus that the ioeventfd handler is no longer required. */ 152 void virtio_bus_cleanup_host_notifier(VirtioBusState *bus, int n); 153 154 #endif /* VIRTIO_BUS_H */ 155