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 38 typedef struct VirtioBusState VirtioBusState; 39 40 typedef 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 * Whether queue number n is enabled. 88 */ 89 bool (*queue_enabled)(DeviceState *d, int n); 90 /* 91 * Does the transport have variable vring alignment? 92 * (ie can it ever call virtio_queue_set_align()?) 93 * Note that changing this will break migration for this transport. 94 */ 95 bool has_variable_vring_alignment; 96 AddressSpace *(*get_dma_as)(DeviceState *d); 97 } VirtioBusClass; 98 99 struct VirtioBusState { 100 BusState parent_obj; 101 102 /* 103 * Set if ioeventfd has been started. 104 */ 105 bool ioeventfd_started; 106 107 /* 108 * Set if ioeventfd has been grabbed by vhost. When ioeventfd 109 * is grabbed by vhost, we track its started/stopped state (which 110 * depends in turn on the virtio status register), but do not 111 * register a handler for the ioeventfd. When ioeventfd is 112 * released, if ioeventfd_started is true we finally register 113 * the handler so that QEMU's device model can use ioeventfd. 114 */ 115 int ioeventfd_grabbed; 116 }; 117 118 void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp); 119 void virtio_bus_reset(VirtioBusState *bus); 120 void virtio_bus_device_unplugged(VirtIODevice *bus); 121 /* Get the device id of the plugged device. */ 122 uint16_t virtio_bus_get_vdev_id(VirtioBusState *bus); 123 /* Get the config_len field of the plugged device. */ 124 size_t virtio_bus_get_vdev_config_len(VirtioBusState *bus); 125 /* Get bad features of the plugged device. */ 126 uint32_t virtio_bus_get_vdev_bad_features(VirtioBusState *bus); 127 /* Get config of the plugged device. */ 128 void virtio_bus_get_vdev_config(VirtioBusState *bus, uint8_t *config); 129 /* Set config of the plugged device. */ 130 void virtio_bus_set_vdev_config(VirtioBusState *bus, uint8_t *config); 131 132 static inline VirtIODevice *virtio_bus_get_device(VirtioBusState *bus) 133 { 134 BusState *qbus = &bus->parent_obj; 135 BusChild *kid = QTAILQ_FIRST(&qbus->children); 136 DeviceState *qdev = kid ? kid->child : NULL; 137 138 /* This is used on the data path, the cast is guaranteed 139 * to succeed by the qdev machinery. 140 */ 141 return (VirtIODevice *)qdev; 142 } 143 144 /* Return whether the proxy allows ioeventfd. */ 145 bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus); 146 /* Start the ioeventfd. */ 147 int virtio_bus_start_ioeventfd(VirtioBusState *bus); 148 /* Stop the ioeventfd. */ 149 void virtio_bus_stop_ioeventfd(VirtioBusState *bus); 150 /* Tell the bus that vhost is grabbing the ioeventfd. */ 151 int virtio_bus_grab_ioeventfd(VirtioBusState *bus); 152 /* bus that vhost is not using the ioeventfd anymore. */ 153 void virtio_bus_release_ioeventfd(VirtioBusState *bus); 154 /* Switch from/to the generic ioeventfd handler */ 155 int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign); 156 /* Tell the bus that the ioeventfd handler is no longer required. */ 157 void virtio_bus_cleanup_host_notifier(VirtioBusState *bus, int n); 158 159 #endif /* VIRTIO_BUS_H */ 160