/* * QEMU Hyper-V VMBus * * Copyright (c) 2017-2018 Virtuozzo International GmbH. * * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. */ #ifndef HW_HYPERV_VMBUS_H #define HW_HYPERV_VMBUS_H #include "sysemu/sysemu.h" #include "sysemu/dma.h" #include "hw/qdev-core.h" #include "migration/vmstate.h" #include "hw/hyperv/vmbus-proto.h" #include "qemu/uuid.h" #include "qom/object.h" #define TYPE_VMBUS_DEVICE "vmbus-dev" OBJECT_DECLARE_TYPE(VMBusDevice, VMBusDeviceClass, vmbus_device, VMBUS_DEVICE) #define TYPE_VMBUS "vmbus" typedef struct VMBus VMBus; DECLARE_INSTANCE_CHECKER(VMBus, VMBUS, TYPE_VMBUS) /* * Object wrapping a GPADL -- GPA Descriptor List -- an array of guest physical * pages, to be used for various buffers shared between the host and the guest. */ typedef struct VMBusGpadl VMBusGpadl; /* * VMBus channel -- a pair of ring buffers for either direction, placed within * one GPADL, and the associated notification means. */ typedef struct VMBusChannel VMBusChannel; /* * Base class for VMBus devices. Includes one or more channels. Identified by * class GUID and instance GUID. */ typedef void(*VMBusChannelNotifyCb)(struct VMBusChannel *chan); struct VMBusDeviceClass { DeviceClass parent; QemuUUID classid; QemuUUID instanceid; /* Fixed UUID for singleton devices */ uint16_t channel_flags; uint16_t mmio_size_mb; /* Extentions to standard device callbacks */ void (*vmdev_realize)(VMBusDevice *vdev, Error **errp); void (*vmdev_unrealize)(VMBusDevice *vdev); void (*vmdev_reset)(VMBusDevice *vdev); /* * Calculate the number of channels based on the device properties. Called * at realize time. **/ uint16_t (*num_channels)(VMBusDevice *vdev); /* * Device-specific actions to complete the otherwise successful process of * opening a channel. * Return 0 on success, -errno on failure. */ int (*open_channel)(VMBusChannel *chan); /* * Device-specific actions to perform before closing a channel. */ void (*close_channel)(VMBusChannel *chan); /* * Main device worker; invoked in response to notifications from either * side, when there's work to do with the data in the channel ring buffers. */ VMBusChannelNotifyCb chan_notify_cb; }; struct VMBusDevice { DeviceState parent; QemuUUID instanceid; uint16_t num_channels; VMBusChannel *channels; AddressSpace *dma_as; }; extern const VMStateDescription vmstate_vmbus_dev; /* * A unit of work parsed out of a message in the receive (i.e. guest->host) * ring buffer of a channel. It's supposed to be subclassed (through * embedding) by the specific devices. */ typedef struct VMBusChanReq { VMBusChannel *chan; uint16_t pkt_type; uint32_t msglen; void *msg; uint64_t transaction_id; bool need_comp; QEMUSGList sgl; } VMBusChanReq; VMBusDevice *vmbus_channel_device(VMBusChannel *chan); VMBusChannel *vmbus_device_channel(VMBusDevice *dev, uint32_t chan_idx); uint32_t vmbus_channel_idx(VMBusChannel *chan); bool vmbus_channel_is_open(VMBusChannel *chan); /* * Notify (on guest's behalf) the host side of the channel that there's data in * the ringbuffer to process. */ void vmbus_channel_notify_host(VMBusChannel *chan); /* * Reserve space for a packet in the send (i.e. host->guest) ringbuffer. If * there isn't enough room, indicate that to the guest, to be notified when it * becomes available. * Return 0 on success, negative errno on failure. * The ringbuffer indices are NOT updated, the requested space indicator may. */ int vmbus_channel_reserve(VMBusChannel *chan, uint32_t desclen, uint32_t msglen); /* * Send a packet to the guest. The space for the packet MUST be reserved * first. * Return total number of bytes placed in the send ringbuffer on success, * negative errno on failure. * The ringbuffer indices are updated on success, and the guest is signaled if * needed. */ ssize_t vmbus_channel_send(VMBusChannel *chan, uint16_t pkt_type, void *desc, uint32_t desclen, void *msg, uint32_t msglen, bool need_comp, uint64_t transaction_id); /* * Prepare to fetch a batch of packets from the receive ring buffer. * Return 0 on success, negative errno on failure. */ int vmbus_channel_recv_start(VMBusChannel *chan); /* * Shortcut for a common case of sending a simple completion packet with no * auxiliary descriptors. */ ssize_t vmbus_channel_send_completion(VMBusChanReq *req, void *msg, uint32_t msglen); /* * Peek at the receive (i.e. guest->host) ring buffer and extract a unit of * work (a device-specific subclass of VMBusChanReq) from a packet if there's * one. * Return an allocated buffer, containing the request of @size with filled * VMBusChanReq at the beginning, followed by the message payload, or NULL on * failure. * The ringbuffer indices are NOT updated, nor is the private copy of the read * index. */ void *vmbus_channel_recv_peek(VMBusChannel *chan, uint32_t size); /* * Update the private copy of the read index once the preceding peek is deemed * successful. * The ringbuffer indices are NOT updated. */ void vmbus_channel_recv_pop(VMBusChannel *chan); /* * Propagate the private copy of the read index into the receive ring buffer, * and thus complete the reception of a series of packets. Notify guest if * needed. * Return the number of bytes popped off the receive ring buffer by the * preceding recv_peek/recv_pop calls on success, negative errno on failure. */ ssize_t vmbus_channel_recv_done(VMBusChannel *chan); /* * Free the request allocated by vmbus_channel_recv_peek, together with its * fields. */ void vmbus_free_req(void *req); /* * Find and reference a GPADL by @gpadl_id. * If not found return NULL. */ VMBusGpadl *vmbus_get_gpadl(VMBusChannel *chan, uint32_t gpadl_id); /* * Unreference @gpadl. If the reference count drops to zero, free it. * @gpadl may be NULL, in which case nothing is done. */ void vmbus_put_gpadl(VMBusGpadl *gpadl); /* * Calculate total length in bytes of @gpadl. * @gpadl must be valid. */ uint32_t vmbus_gpadl_len(VMBusGpadl *gpadl); /* * Copy data from @iov to @gpadl at offset @off. * Return the number of bytes copied, or a negative status on failure. */ ssize_t vmbus_iov_to_gpadl(VMBusChannel *chan, VMBusGpadl *gpadl, uint32_t off, const struct iovec *iov, size_t iov_cnt); /* * Map SGList contained in the request @req, at offset @off and no more than * @len bytes, for io in direction @dir, and populate @iov with the mapped * iovecs. * Return the number of iovecs mapped, or negative status on failure. */ int vmbus_map_sgl(VMBusChanReq *req, DMADirection dir, struct iovec *iov, unsigned iov_cnt, size_t len, size_t off); /* * Unmap *iov mapped with vmbus_map_sgl, marking the number of bytes @accessed. */ void vmbus_unmap_sgl(VMBusChanReq *req, DMADirection dir, struct iovec *iov, unsigned iov_cnt, size_t accessed); void vmbus_save_req(QEMUFile *f, VMBusChanReq *req); void *vmbus_load_req(QEMUFile *f, VMBusDevice *dev, uint32_t size); #endif