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 #include "qom/object.h" 31 32 #define TYPE_VIRTIO_BUS "virtio-bus" 33 typedef struct VirtioBusClass VirtioBusClass; 34 typedef struct VirtioBusState VirtioBusState; 35 DECLARE_OBJ_CHECKERS(VirtioBusState, VirtioBusClass, 36 VIRTIO_BUS, TYPE_VIRTIO_BUS) 37 38 39 struct VirtioBusClass { 40 /* This is what a VirtioBus must implement */ 41 BusClass parent; 42 void (*notify)(DeviceState *d, uint16_t vector); 43 void (*save_config)(DeviceState *d, QEMUFile *f); 44 void (*save_queue)(DeviceState *d, int n, QEMUFile *f); 45 void (*save_extra_state)(DeviceState *d, QEMUFile *f); 46 int (*load_config)(DeviceState *d, QEMUFile *f); 47 int (*load_queue)(DeviceState *d, int n, QEMUFile *f); 48 int (*load_done)(DeviceState *d, QEMUFile *f); 49 int (*load_extra_state)(DeviceState *d, QEMUFile *f); 50 bool (*has_extra_state)(DeviceState *d); 51 bool (*query_guest_notifiers)(DeviceState *d); 52 int (*set_guest_notifiers)(DeviceState *d, int nvqs, bool assign); 53 int (*set_host_notifier_mr)(DeviceState *d, int n, 54 MemoryRegion *mr, 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 * Whether queue number n is enabled. 87 */ 88 bool (*queue_enabled)(DeviceState *d, int n); 89 /* 90 * Does the transport have variable vring alignment? 91 * (ie can it ever call virtio_queue_set_align()?) 92 * Note that changing this will break migration for this transport. 93 */ 94 bool has_variable_vring_alignment; 95 AddressSpace *(*get_dma_as)(DeviceState *d); 96 }; 97 98 struct VirtioBusState { 99 BusState parent_obj; 100 101 /* 102 * Set if ioeventfd has been started. 103 */ 104 bool ioeventfd_started; 105 106 /* 107 * Set if ioeventfd has been grabbed by vhost. When ioeventfd 108 * is grabbed by vhost, we track its started/stopped state (which 109 * depends in turn on the virtio status register), but do not 110 * register a handler for the ioeventfd. When ioeventfd is 111 * released, if ioeventfd_started is true we finally register 112 * the handler so that QEMU's device model can use ioeventfd. 113 */ 114 int ioeventfd_grabbed; 115 }; 116 117 void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp); 118 void virtio_bus_reset(VirtioBusState *bus); 119 void virtio_bus_device_unplugged(VirtIODevice *bus); 120 /* Get the device id of the plugged device. */ 121 uint16_t virtio_bus_get_vdev_id(VirtioBusState *bus); 122 /* Get the config_len field of the plugged device. */ 123 size_t virtio_bus_get_vdev_config_len(VirtioBusState *bus); 124 /* Get bad features of the plugged device. */ 125 uint32_t virtio_bus_get_vdev_bad_features(VirtioBusState *bus); 126 /* Get config of the plugged device. */ 127 void virtio_bus_get_vdev_config(VirtioBusState *bus, uint8_t *config); 128 /* Set config of the plugged device. */ 129 void virtio_bus_set_vdev_config(VirtioBusState *bus, uint8_t *config); 130 131 static inline VirtIODevice *virtio_bus_get_device(VirtioBusState *bus) 132 { 133 BusState *qbus = &bus->parent_obj; 134 BusChild *kid = QTAILQ_FIRST(&qbus->children); 135 DeviceState *qdev = kid ? kid->child : NULL; 136 137 /* This is used on the data path, the cast is guaranteed 138 * to succeed by the qdev machinery. 139 */ 140 return (VirtIODevice *)qdev; 141 } 142 143 /* Return whether the proxy allows ioeventfd. */ 144 bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus); 145 /* Start the ioeventfd. */ 146 int virtio_bus_start_ioeventfd(VirtioBusState *bus); 147 /* Stop the ioeventfd. */ 148 void virtio_bus_stop_ioeventfd(VirtioBusState *bus); 149 /* Tell the bus that vhost is grabbing the ioeventfd. */ 150 int virtio_bus_grab_ioeventfd(VirtioBusState *bus); 151 /* bus that vhost is not using the ioeventfd anymore. */ 152 void virtio_bus_release_ioeventfd(VirtioBusState *bus); 153 /* Switch from/to the generic ioeventfd handler */ 154 int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign); 155 /* Tell the bus that the ioeventfd handler is no longer required. */ 156 void virtio_bus_cleanup_host_notifier(VirtioBusState *bus, int n); 157 158 #endif /* VIRTIO_BUS_H */ 159