freebsd-dev/sys/dev/virtio/virtio.h
Peter Grehan 10b59a9b4a Import virtio base, PCI front-end, and net/block/balloon drivers.
Tested on Qemu/KVM, VirtualBox, and BHyVe.

Currently built as modules-only on i386/amd64. Man pages not yet hooked
up, pending review.

Submitted by:	Bryan Venteicher  bryanv at daemoninthecloset dot org
Reviewed by:	bz
MFC after:	4 weeks or so
2011-11-18 05:43:43 +00:00

131 lines
3.8 KiB
C

/*
* This header is BSD licensed so anyone can use the definitions to implement
* compatible drivers/servers.
*
* $FreeBSD$
*/
#ifndef _VIRTIO_H_
#define _VIRTIO_H_
#include <sys/types.h>
struct vq_alloc_info;
/* VirtIO device IDs. */
#define VIRTIO_ID_NETWORK 0x01
#define VIRTIO_ID_BLOCK 0x02
#define VIRTIO_ID_CONSOLE 0x03
#define VIRTIO_ID_ENTROPY 0x04
#define VIRTIO_ID_BALLOON 0x05
#define VIRTIO_ID_IOMEMORY 0x06
#define VIRTIO_ID_9P 0x09
/* Status byte for guest to report progress. */
#define VIRTIO_CONFIG_STATUS_RESET 0x00
#define VIRTIO_CONFIG_STATUS_ACK 0x01
#define VIRTIO_CONFIG_STATUS_DRIVER 0x02
#define VIRTIO_CONFIG_STATUS_DRIVER_OK 0x04
#define VIRTIO_CONFIG_STATUS_FAILED 0x80
/*
* Generate interrupt when the virtqueue ring is
* completely used, even if we've suppressed them.
*/
#define VIRTIO_F_NOTIFY_ON_EMPTY (1 << 24)
/*
* The guest should never negotiate this feature; it
* is used to detect faulty drivers.
*/
#define VIRTIO_F_BAD_FEATURE (1 << 30)
/*
* Some VirtIO feature bits (currently bits 28 through 31) are
* reserved for the transport being used (eg. virtio_ring), the
* rest are per-device feature bits.
*/
#define VIRTIO_TRANSPORT_F_START 28
#define VIRTIO_TRANSPORT_F_END 32
/*
* Maximum number of virtqueues per device.
*/
#define VIRTIO_MAX_VIRTQUEUES 8
/*
* Each virtqueue indirect descriptor list must be physically contiguous.
* To allow us to malloc(9) each list individually, limit the number
* supported to what will fit in one page. With 4KB pages, this is a limit
* of 256 descriptors. If there is ever a need for more, we can switch to
* contigmalloc(9) for the larger allocations, similar to what
* bus_dmamem_alloc(9) does.
*
* Note the sizeof(struct vring_desc) is 16 bytes.
*/
#define VIRTIO_MAX_INDIRECT ((int) (PAGE_SIZE / 16))
/*
* VirtIO instance variables indices.
*/
#define VIRTIO_IVAR_DEVTYPE 1
#define VIRTIO_IVAR_FEATURE_DESC 2
struct virtio_feature_desc {
uint64_t vfd_val;
char *vfd_str;
};
const char *virtio_device_name(uint16_t devid);
int virtio_get_device_type(device_t dev);
void virtio_set_feature_desc(device_t dev,
struct virtio_feature_desc *feature_desc);
void virtio_describe(device_t dev, const char *msg,
uint64_t features, struct virtio_feature_desc *feature_desc);
/*
* VirtIO Bus Methods.
*/
uint64_t virtio_negotiate_features(device_t dev, uint64_t child_features);
int virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
struct vq_alloc_info *info);
int virtio_setup_intr(device_t dev, enum intr_type type);
int virtio_with_feature(device_t dev, uint64_t feature);
void virtio_stop(device_t dev);
int virtio_reinit(device_t dev, uint64_t features);
void virtio_reinit_complete(device_t dev);
/*
* Read/write a variable amount from the device specific (ie, network)
* configuration region. This region is encoded in the same endian as
* the guest.
*/
void virtio_read_device_config(device_t dev, bus_size_t offset,
void *dst, int length);
void virtio_write_device_config(device_t dev, bus_size_t offset,
void *src, int length);
/* Inlined device specific read/write functions for common lengths. */
#define VIRTIO_RDWR_DEVICE_CONFIG(size, type) \
static inline type \
__CONCAT(virtio_read_dev_config_,size)(device_t dev, \
bus_size_t offset) \
{ \
type val; \
virtio_read_device_config(dev, offset, &val, sizeof(type)); \
return (val); \
} \
\
static inline void \
__CONCAT(virtio_write_dev_config_,size)(device_t dev, \
bus_size_t offset, type val) \
{ \
virtio_write_device_config(dev, offset, &val, sizeof(type)); \
}
VIRTIO_RDWR_DEVICE_CONFIG(1, uint8_t);
VIRTIO_RDWR_DEVICE_CONFIG(2, uint16_t);
VIRTIO_RDWR_DEVICE_CONFIG(4, uint32_t);
#endif /* _VIRTIO_H_ */