98 lines
2.8 KiB
C
98 lines
2.8 KiB
C
/*
|
|
* Copyright (c) 2006-2023, RT-Thread Development Team
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*
|
|
* Change Logs:
|
|
* Date Author Notes
|
|
* 2021-11-11 GuEe-GUI the first version
|
|
*/
|
|
|
|
#ifndef __VIRTIO_QUEUE_H__
|
|
#define __VIRTIO_QUEUE_H__
|
|
|
|
#include <rtdef.h>
|
|
|
|
#define VIRTQ_DESC_F_NEXT 1 /* This marks a buffer as continuing via the next field. */
|
|
#define VIRTQ_DESC_F_WRITE 2 /* This marks a buffer as write-only (otherwise read-only). */
|
|
#define VIRTQ_DESC_F_INDIRECT 4 /* This means the buffer contains a list of buffer descriptors. */
|
|
|
|
/*
|
|
* The device uses this in used->flags to advise the driver: don't kick me
|
|
* when you add a buffer. It's unreliable, so it's simply an optimization.
|
|
*/
|
|
#define VIRTQ_USED_F_NO_NOTIFY 1
|
|
|
|
/*
|
|
* The driver uses this in avail->flags to advise the device: don't
|
|
* interrupt me when you consume a buffer. It's unreliable, so it's
|
|
* simply an optimization.
|
|
*/
|
|
#define VIRTQ_AVAIL_F_NO_INTERRUPT 1
|
|
|
|
/* Virtqueue descriptors: 16 bytes. These can chain together via "next". */
|
|
struct virtq_desc
|
|
{
|
|
rt_uint64_t addr; /* Address (guest-physical). */
|
|
rt_uint32_t len; /* Length. */
|
|
rt_uint16_t flags; /* The flags as indicated above. */
|
|
rt_uint16_t next; /* We chain unused descriptors via this, too */
|
|
};
|
|
|
|
struct virtq_avail
|
|
{
|
|
rt_uint16_t flags; /* Notifications */
|
|
rt_uint16_t idx; /* Where the driver would put the next descriptor entry in the ring (modulo the queue size) */
|
|
rt_uint16_t ring[];
|
|
|
|
/*
|
|
* Only if VIRTIO_F_RING_EVENT_IDX
|
|
* rt_uint16_t used_event;
|
|
*/
|
|
};
|
|
|
|
struct virtq_used_elem
|
|
{
|
|
rt_uint32_t id; /* Index of start of used descriptor chain. */
|
|
rt_uint32_t len; /* Total length of the descriptor chain which was written to. */
|
|
};
|
|
|
|
struct virtq_used
|
|
{
|
|
rt_uint16_t flags;
|
|
rt_uint16_t idx;
|
|
struct virtq_used_elem ring[];
|
|
|
|
/*
|
|
* Only if VIRTIO_F_RING_EVENT_IDX
|
|
* rt_uint16_t avail_event;
|
|
*/
|
|
};
|
|
|
|
struct virtq
|
|
{
|
|
rt_uint32_t num;
|
|
|
|
struct virtq_desc *desc;
|
|
struct virtq_avail *avail;
|
|
struct virtq_used *used;
|
|
|
|
/* Helper of driver */
|
|
rt_uint16_t used_idx;
|
|
rt_bool_t *free;
|
|
rt_size_t free_count;
|
|
};
|
|
|
|
#define VIRTQ_DESC_TOTAL_SIZE(ring_size) (sizeof(struct virtq_desc) * (ring_size))
|
|
/* flags, idx, used_event + ring * ring_size */
|
|
#define VIRTQ_AVAIL_TOTAL_SIZE(ring_size) (sizeof(rt_uint16_t) * 3 + sizeof(rt_uint16_t) * (ring_size))
|
|
/* flags, idx, avail_event + ring * ring_size */
|
|
#define VIRTQ_USED_TOTAL_SIZE(ring_size) (sizeof(rt_uint16_t) * 3 + sizeof(struct virtq_used_elem) * (ring_size))
|
|
|
|
#define VIRTQ_AVAIL_RES_SIZE (sizeof(rt_uint16_t)) /* used_event */
|
|
#define VIRTQ_USED_RES_SIZE (sizeof(rt_uint16_t)) /* avail_event */
|
|
|
|
#define VIRTQ_INVALID_DESC_ID RT_UINT16_MAX
|
|
|
|
#endif /* __VIRTIO_QUEUE_H__ */
|