1 /* 2 * QEMU Hyper-V VMBus 3 * 4 * Copyright (c) 2017-2018 Virtuozzo International GmbH. 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 */ 9 10 #ifndef HW_HYPERV_VMBUS_H 11 #define HW_HYPERV_VMBUS_H 12 13 #include "sysemu/sysemu.h" 14 #include "sysemu/dma.h" 15 #include "hw/qdev-core.h" 16 #include "migration/vmstate.h" 17 #include "hw/hyperv/vmbus-proto.h" 18 #include "qemu/uuid.h" 19 #include "qom/object.h" 20 21 #define TYPE_VMBUS_DEVICE "vmbus-dev" 22 23 typedef struct VMBusDevice VMBusDevice; 24 typedef struct VMBusDeviceClass VMBusDeviceClass; 25 DECLARE_OBJ_CHECKERS(VMBusDevice, VMBusDeviceClass, 26 VMBUS_DEVICE, TYPE_VMBUS_DEVICE) 27 28 #define TYPE_VMBUS "vmbus" 29 typedef struct VMBus VMBus; 30 DECLARE_INSTANCE_CHECKER(VMBus, VMBUS, 31 TYPE_VMBUS) 32 33 /* 34 * Object wrapping a GPADL -- GPA Descriptor List -- an array of guest physical 35 * pages, to be used for various buffers shared between the host and the guest. 36 */ 37 typedef struct VMBusGpadl VMBusGpadl; 38 /* 39 * VMBus channel -- a pair of ring buffers for either direction, placed within 40 * one GPADL, and the associated notification means. 41 */ 42 typedef struct VMBusChannel VMBusChannel; 43 /* 44 * Base class for VMBus devices. Includes one or more channels. Identified by 45 * class GUID and instance GUID. 46 */ 47 48 typedef void(*VMBusChannelNotifyCb)(struct VMBusChannel *chan); 49 50 struct VMBusDeviceClass { 51 DeviceClass parent; 52 53 QemuUUID classid; 54 QemuUUID instanceid; /* Fixed UUID for singleton devices */ 55 uint16_t channel_flags; 56 uint16_t mmio_size_mb; 57 58 /* Extentions to standard device callbacks */ 59 void (*vmdev_realize)(VMBusDevice *vdev, Error **errp); 60 void (*vmdev_unrealize)(VMBusDevice *vdev); 61 void (*vmdev_reset)(VMBusDevice *vdev); 62 /* 63 * Calculate the number of channels based on the device properties. Called 64 * at realize time. 65 **/ 66 uint16_t (*num_channels)(VMBusDevice *vdev); 67 /* 68 * Device-specific actions to complete the otherwise successful process of 69 * opening a channel. 70 * Return 0 on success, -errno on failure. 71 */ 72 int (*open_channel)(VMBusChannel *chan); 73 /* 74 * Device-specific actions to perform before closing a channel. 75 */ 76 void (*close_channel)(VMBusChannel *chan); 77 /* 78 * Main device worker; invoked in response to notifications from either 79 * side, when there's work to do with the data in the channel ring buffers. 80 */ 81 VMBusChannelNotifyCb chan_notify_cb; 82 }; 83 84 struct VMBusDevice { 85 DeviceState parent; 86 QemuUUID instanceid; 87 uint16_t num_channels; 88 VMBusChannel *channels; 89 AddressSpace *dma_as; 90 }; 91 92 extern const VMStateDescription vmstate_vmbus_dev; 93 94 /* 95 * A unit of work parsed out of a message in the receive (i.e. guest->host) 96 * ring buffer of a channel. It's supposed to be subclassed (through 97 * embedding) by the specific devices. 98 */ 99 typedef struct VMBusChanReq { 100 VMBusChannel *chan; 101 uint16_t pkt_type; 102 uint32_t msglen; 103 void *msg; 104 uint64_t transaction_id; 105 bool need_comp; 106 QEMUSGList sgl; 107 } VMBusChanReq; 108 109 VMBusDevice *vmbus_channel_device(VMBusChannel *chan); 110 VMBusChannel *vmbus_device_channel(VMBusDevice *dev, uint32_t chan_idx); 111 uint32_t vmbus_channel_idx(VMBusChannel *chan); 112 bool vmbus_channel_is_open(VMBusChannel *chan); 113 114 /* 115 * Notify (on guest's behalf) the host side of the channel that there's data in 116 * the ringbuffer to process. 117 */ 118 void vmbus_channel_notify_host(VMBusChannel *chan); 119 120 /* 121 * Reserve space for a packet in the send (i.e. host->guest) ringbuffer. If 122 * there isn't enough room, indicate that to the guest, to be notified when it 123 * becomes available. 124 * Return 0 on success, negative errno on failure. 125 * The ringbuffer indices are NOT updated, the requested space indicator may. 126 */ 127 int vmbus_channel_reserve(VMBusChannel *chan, 128 uint32_t desclen, uint32_t msglen); 129 130 /* 131 * Send a packet to the guest. The space for the packet MUST be reserved 132 * first. 133 * Return total number of bytes placed in the send ringbuffer on success, 134 * negative errno on failure. 135 * The ringbuffer indices are updated on success, and the guest is signaled if 136 * needed. 137 */ 138 ssize_t vmbus_channel_send(VMBusChannel *chan, uint16_t pkt_type, 139 void *desc, uint32_t desclen, 140 void *msg, uint32_t msglen, 141 bool need_comp, uint64_t transaction_id); 142 143 /* 144 * Prepare to fetch a batch of packets from the receive ring buffer. 145 * Return 0 on success, negative errno on failure. 146 */ 147 int vmbus_channel_recv_start(VMBusChannel *chan); 148 149 /* 150 * Shortcut for a common case of sending a simple completion packet with no 151 * auxiliary descriptors. 152 */ 153 ssize_t vmbus_channel_send_completion(VMBusChanReq *req, 154 void *msg, uint32_t msglen); 155 156 /* 157 * Peek at the receive (i.e. guest->host) ring buffer and extract a unit of 158 * work (a device-specific subclass of VMBusChanReq) from a packet if there's 159 * one. 160 * Return an allocated buffer, containing the request of @size with filled 161 * VMBusChanReq at the beginning, followed by the message payload, or NULL on 162 * failure. 163 * The ringbuffer indices are NOT updated, nor is the private copy of the read 164 * index. 165 */ 166 void *vmbus_channel_recv_peek(VMBusChannel *chan, uint32_t size); 167 168 /* 169 * Update the private copy of the read index once the preceding peek is deemed 170 * successful. 171 * The ringbuffer indices are NOT updated. 172 */ 173 void vmbus_channel_recv_pop(VMBusChannel *chan); 174 175 /* 176 * Propagate the private copy of the read index into the receive ring buffer, 177 * and thus complete the reception of a series of packets. Notify guest if 178 * needed. 179 * Return the number of bytes popped off the receive ring buffer by the 180 * preceding recv_peek/recv_pop calls on success, negative errno on failure. 181 */ 182 ssize_t vmbus_channel_recv_done(VMBusChannel *chan); 183 184 /* 185 * Free the request allocated by vmbus_channel_recv_peek, together with its 186 * fields. 187 */ 188 void vmbus_free_req(void *req); 189 190 /* 191 * Find and reference a GPADL by @gpadl_id. 192 * If not found return NULL. 193 */ 194 VMBusGpadl *vmbus_get_gpadl(VMBusChannel *chan, uint32_t gpadl_id); 195 196 /* 197 * Unreference @gpadl. If the reference count drops to zero, free it. 198 * @gpadl may be NULL, in which case nothing is done. 199 */ 200 void vmbus_put_gpadl(VMBusGpadl *gpadl); 201 202 /* 203 * Calculate total length in bytes of @gpadl. 204 * @gpadl must be valid. 205 */ 206 uint32_t vmbus_gpadl_len(VMBusGpadl *gpadl); 207 208 /* 209 * Copy data from @iov to @gpadl at offset @off. 210 * Return the number of bytes copied, or a negative status on failure. 211 */ 212 ssize_t vmbus_iov_to_gpadl(VMBusChannel *chan, VMBusGpadl *gpadl, uint32_t off, 213 const struct iovec *iov, size_t iov_cnt); 214 215 /* 216 * Map SGList contained in the request @req, at offset @off and no more than 217 * @len bytes, for io in direction @dir, and populate @iov with the mapped 218 * iovecs. 219 * Return the number of iovecs mapped, or negative status on failure. 220 */ 221 int vmbus_map_sgl(VMBusChanReq *req, DMADirection dir, struct iovec *iov, 222 unsigned iov_cnt, size_t len, size_t off); 223 224 /* 225 * Unmap *iov mapped with vmbus_map_sgl, marking the number of bytes @accessed. 226 */ 227 void vmbus_unmap_sgl(VMBusChanReq *req, DMADirection dir, struct iovec *iov, 228 unsigned iov_cnt, size_t accessed); 229 230 void vmbus_save_req(QEMUFile *f, VMBusChanReq *req); 231 void *vmbus_load_req(QEMUFile *f, VMBusDevice *dev, uint32_t size); 232 233 #endif 234