freebsd-dev/sys/dev/virtio/virtqueue.h
Peter Grehan 310dacd09b Various VirtIO improvements
PCI:
        - Properly handle interrupt fallback from MSIX to MSI to legacy.
          The host may not have sufficient resources to support MSIX,
          so we must be able to fallback to legacy interrupts.
        - Add interface to get the (sub) vendor and device IDs.
        - Rename flags to VTPCI_FLAG_* like other VirtIO drivers.
      Block:
        - No longer allocate vtblk_requests from separate UMA zone.
          malloc(9) from M_DEVBUF is sufficient. Assert segment counts
          at allocation.
        - More verbose error and debug messages.
      Network:
        - Remove stray write once variable.
      Virtqueue:
        - Shuffle code around in preparation of converting the mb()s to
          the appropriate atomic(9) operations.
        - Only walk the descriptor chain when freeing if INVARIANTS is
          defined since the result is only KASSERT()ed.

Submitted by:	Bryan Venteicher (bryanv@daemoninthecloset.org)
2012-07-11 02:57:19 +00:00

94 lines
3.5 KiB
C

/*-
* Copyright (c) 2011, Bryan Venteicher <bryanv@daemoninthecloset.org>
* All rights reserved.
*
* 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 unmodified, 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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_VIRTQUEUE_H
#define _VIRTIO_VIRTQUEUE_H
struct virtqueue;
struct sglist;
/* Support for indirect buffer descriptors. */
#define VIRTIO_RING_F_INDIRECT_DESC (1 << 28)
/* Support to suppress interrupt until specific index is reached. */
#define VIRTIO_RING_F_EVENT_IDX (1 << 29)
/* Device callback for a virtqueue interrupt. */
typedef int virtqueue_intr_t(void *);
#define VIRTQUEUE_MAX_NAME_SZ 32
/* One for each virtqueue the device wishes to allocate. */
struct vq_alloc_info {
char vqai_name[VIRTQUEUE_MAX_NAME_SZ];
int vqai_maxindirsz;
virtqueue_intr_t *vqai_intr;
void *vqai_intr_arg;
struct virtqueue **vqai_vq;
};
#define VQ_ALLOC_INFO_INIT(_i,_nsegs,_intr,_arg,_vqp,_str,...) do { \
snprintf((_i)->vqai_name, VIRTQUEUE_MAX_NAME_SZ, _str, \
##__VA_ARGS__); \
(_i)->vqai_maxindirsz = (_nsegs); \
(_i)->vqai_intr = (_intr); \
(_i)->vqai_intr_arg = (_arg); \
(_i)->vqai_vq = (_vqp); \
} while (0)
uint64_t virtqueue_filter_features(uint64_t features);
int virtqueue_alloc(device_t dev, uint16_t queue, uint16_t size,
int align, vm_paddr_t highaddr, struct vq_alloc_info *info,
struct virtqueue **vqp);
void *virtqueue_drain(struct virtqueue *vq, int *last);
void virtqueue_free(struct virtqueue *vq);
int virtqueue_reinit(struct virtqueue *vq, uint16_t size);
int virtqueue_intr(struct virtqueue *vq);
int virtqueue_enable_intr(struct virtqueue *vq);
int virtqueue_postpone_intr(struct virtqueue *vq);
void virtqueue_disable_intr(struct virtqueue *vq);
/* Get physical address of the virtqueue ring. */
vm_paddr_t virtqueue_paddr(struct virtqueue *vq);
int virtqueue_full(struct virtqueue *vq);
int virtqueue_empty(struct virtqueue *vq);
int virtqueue_size(struct virtqueue *vq);
int virtqueue_nused(struct virtqueue *vq);
void virtqueue_notify(struct virtqueue *vq);
void virtqueue_dump(struct virtqueue *vq);
int virtqueue_enqueue(struct virtqueue *vq, void *cookie,
struct sglist *sg, int readable, int writable);
void *virtqueue_dequeue(struct virtqueue *vq, uint32_t *len);
void *virtqueue_poll(struct virtqueue *vq, uint32_t *len);
#endif /* _VIRTIO_VIRTQUEUE_H */