freebsd-skq/sys/dev/virtio/virtio.h
grehan 789936ed16 Virtio SCSI driver
Submitted by:	Bryan Venteicher  bryanv at daemoninthecloset dot org
Reviewed by:	grehan
2012-10-11 23:41:18 +00:00

186 lines
6.1 KiB
C

/*-
* This header is BSD licensed so anyone can use the definitions to implement
* compatible drivers/servers.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of IBM nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _VIRTIO_H_
#define _VIRTIO_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_SCSI 0x08
#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
#define VIRTIO_IVAR_VENDOR 3
#define VIRTIO_IVAR_DEVICE 4
#define VIRTIO_IVAR_SUBVENDOR 5
#define VIRTIO_IVAR_SUBDEVICE 6
struct virtio_feature_desc {
uint64_t vfd_val;
char *vfd_str;
};
const char *virtio_device_name(uint16_t devid);
void virtio_describe(device_t dev, const char *msg,
uint64_t features, struct virtio_feature_desc *feature_desc);
/*
* VirtIO Bus Methods.
*/
void virtio_read_ivar(device_t dev, int ivar, uintptr_t *val);
void virtio_write_ivar(device_t dev, int ivar, uintptr_t val);
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);
#undef VIRTIO_RDWR_DEVICE_CONFIG
#define VIRTIO_READ_IVAR(name, ivar) \
static inline int \
__CONCAT(virtio_get_,name)(device_t dev) \
{ \
uintptr_t val; \
virtio_read_ivar(dev, ivar, &val); \
return ((int) val); \
}
VIRTIO_READ_IVAR(device_type, VIRTIO_IVAR_DEVTYPE);
VIRTIO_READ_IVAR(vendor, VIRTIO_IVAR_VENDOR);
VIRTIO_READ_IVAR(device, VIRTIO_IVAR_DEVICE);
VIRTIO_READ_IVAR(subvendor, VIRTIO_IVAR_SUBVENDOR);
VIRTIO_READ_IVAR(subdevice, VIRTIO_IVAR_SUBDEVICE);
#undef VIRTIO_READ_IVAR
#define VIRTIO_WRITE_IVAR(name, ivar) \
static inline void \
__CONCAT(virtio_set_,name)(device_t dev, void *val) \
{ \
virtio_write_ivar(dev, ivar, (uintptr_t) val); \
}
VIRTIO_WRITE_IVAR(feature_desc, VIRTIO_IVAR_FEATURE_DESC);
#undef VIRTIO_WRITE_IVAR
#endif /* _VIRTIO_H_ */