/*
* 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)
#define TYPE_VMBUS "vmbus"
OBJECT_DECLARE_SIMPLE_TYPE(VMBus, 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
