virtio-ring.h File Reference

#include <ipxe/virtio-pci.h>
#include <ipxe/dma.h>

Go to the source code of this file.

Data Structures
struct	vring_desc
struct	vring_avail
struct	vring_used_elem
struct	vring_used
struct	vring
struct	vring_virtqueue
struct	vring_list

Macros
#define	VIRTIO_CONFIG_S_ACKNOWLEDGE   1
#define	VIRTIO_CONFIG_S_DRIVER   2
#define	VIRTIO_CONFIG_S_DRIVER_OK   4
#define	VIRTIO_CONFIG_S_FEATURES_OK   8
#define	VIRTIO_CONFIG_S_FAILED   0x80
#define	VIRTIO_F_ANY_LAYOUT   27
#define	VIRTIO_F_VERSION_1   32
#define	VIRTIO_F_IOMMU_PLATFORM   33
#define	MAX_QUEUE_NUM   (256)
#define	VRING_DESC_F_NEXT   1
#define	VRING_DESC_F_WRITE   2
#define	VRING_AVAIL_F_NO_INTERRUPT   1
#define	VRING_USED_F_NO_NOTIFY   1
#define	vring_size(num)

Functions
static void	vring_init (struct vring *vr, unsigned int num, unsigned char *queue)
static void	vring_enable_cb (struct vring_virtqueue *vq)
static void	vring_disable_cb (struct vring_virtqueue *vq)
static int	vring_more_used (struct vring_virtqueue *vq)
void	vring_detach (struct vring_virtqueue *vq, unsigned int head)
void *	vring_get_buf (struct vring_virtqueue *vq, unsigned int *len)
void	vring_add_buf (struct vring_virtqueue *vq, struct vring_list list[], unsigned int out, unsigned int in, void *index, int num_added)
void	vring_kick (struct virtio_pci_modern_device *vdev, unsigned int ioaddr, struct vring_virtqueue *vq, int num_added)

Macro Definition Documentation

VIRTIO_CONFIG_S_ACKNOWLEDGE

#define VIRTIO_CONFIG_S_ACKNOWLEDGE   1

Definition at line 9 of file virtio-ring.h.

VIRTIO_CONFIG_S_DRIVER

#define VIRTIO_CONFIG_S_DRIVER   2

Definition at line 11 of file virtio-ring.h.

VIRTIO_CONFIG_S_DRIVER_OK

#define VIRTIO_CONFIG_S_DRIVER_OK   4

Definition at line 13 of file virtio-ring.h.

VIRTIO_CONFIG_S_FEATURES_OK

#define VIRTIO_CONFIG_S_FEATURES_OK   8

Definition at line 15 of file virtio-ring.h.

VIRTIO_CONFIG_S_FAILED

#define VIRTIO_CONFIG_S_FAILED   0x80

Definition at line 17 of file virtio-ring.h.

VIRTIO_F_ANY_LAYOUT

#define VIRTIO_F_ANY_LAYOUT   27

Definition at line 21 of file virtio-ring.h.

VIRTIO_F_VERSION_1

#define VIRTIO_F_VERSION_1   32

Definition at line 23 of file virtio-ring.h.

VIRTIO_F_IOMMU_PLATFORM

#define VIRTIO_F_IOMMU_PLATFORM   33

Definition at line 24 of file virtio-ring.h.

MAX_QUEUE_NUM

#define MAX_QUEUE_NUM   (256)

Definition at line 26 of file virtio-ring.h.

VRING_DESC_F_NEXT

#define VRING_DESC_F_NEXT   1

Definition at line 28 of file virtio-ring.h.

VRING_DESC_F_WRITE

#define VRING_DESC_F_WRITE   2

Definition at line 29 of file virtio-ring.h.

VRING_AVAIL_F_NO_INTERRUPT

#define VRING_AVAIL_F_NO_INTERRUPT   1

Definition at line 31 of file virtio-ring.h.

VRING_USED_F_NO_NOTIFY

#define VRING_USED_F_NO_NOTIFY   1

Definition at line 33 of file virtio-ring.h.

vring_size

#define vring_size

(

num

)

Value:

(((((sizeof(struct vring_desc) * num) + \
      (sizeof(struct vring_avail) + sizeof(u16) * num)) \
         + PAGE_MASK) & ~PAGE_MASK) + \
         (sizeof(struct vring_used) + sizeof(struct vring_used_elem) * num))

Definition at line 70 of file virtio-ring.h.

Function Documentation

vring_init()

static void vring_init ( struct vring *  vr, unsigned int  num, unsigned char *  queue  )

inlinestatic

Definition at line 96 of file virtio-ring.h.

{
   unsigned int i;
   unsigned long pa;

   vr->num = num;

   /* physical address of desc must be page aligned */

   pa = virt_to_phys(queue);
   pa = (pa + PAGE_MASK) & ~PAGE_MASK;
   vr->desc = phys_to_virt(pa);

   vr->avail = (struct vring_avail *)&vr->desc[num];

   /* physical address of used must be page aligned */

   pa = virt_to_phys(&vr->avail->ring[num]);
   pa = (pa + PAGE_MASK) & ~PAGE_MASK;
   vr->used = phys_to_virt(pa);

   for (i = 0; i < num - 1; i++)
           vr->desc[i].next = i + 1;
   vr->desc[i].next = 0;
}

References vring::avail, vring::desc, vring_desc::next, num, vring::num, PAGE_MASK, queue, vring_avail::ring, and vring::used.

Referenced by vp_find_vq(), and vpm_find_vqs().

vring_enable_cb()

static void vring_enable_cb ( struct vring_virtqueue *  vq )

inlinestatic

Definition at line 123 of file virtio-ring.h.

{
   vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
}

References vring::avail, vring_avail::flags, vring_virtqueue::vring, and VRING_AVAIL_F_NO_INTERRUPT.

Referenced by virtnet_irq().

vring_disable_cb()

static void vring_disable_cb ( struct vring_virtqueue *  vq )

inlinestatic

Definition at line 128 of file virtio-ring.h.

{
   vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
}

References vring::avail, vring_avail::flags, vring_virtqueue::vring, and VRING_AVAIL_F_NO_INTERRUPT.

Referenced by virtnet_irq().

vring_more_used()

static int vring_more_used ( struct vring_virtqueue *  vq )

inlinestatic

Definition at line 141 of file virtio-ring.h.

{
   wmb();
   return vq->last_used_idx != vq->vring.used->idx;
}

References vring_used::idx, vring_virtqueue::last_used_idx, vring::used, vring_virtqueue::vring, and wmb().

Referenced by virtnet_process_rx_packets(), virtnet_process_tx_packets(), and vring_get_buf().

vring_detach()

void vring_detach	(	struct vring_virtqueue *	vq,
		unsigned int	head
	)

Definition at line 37 of file virtio-ring.c.

{
   struct vring *vr = &vq->vring;
   unsigned int i;

   /* find end of given descriptor */

   i = head;
   while (vr->desc[i].flags & VRING_DESC_F_NEXT)
           i = vr->desc[i].next;

   /* link it with free list and point to it */

   vr->desc[i].next = vq->free_head;
   wmb();
   vq->free_head = head;
}

References vring::desc, vring_desc::flags, vring_virtqueue::free_head, head, vring_desc::next, vring_virtqueue::vring, VRING_DESC_F_NEXT, and wmb().

Referenced by vring_get_buf().

vring_get_buf()

void* vring_get_buf	(	struct vring_virtqueue *	vq,
		unsigned int *	len
	)

Definition at line 62 of file virtio-ring.c.

{
   struct vring *vr = &vq->vring;
   struct vring_used_elem *elem;
   u32 id;
   void *opaque;

   BUG_ON(!vring_more_used(vq));

   elem = &vr->used->ring[vq->last_used_idx % vr->num];
   wmb();
   id = elem->id;
   if (len != NULL)
           *len = elem->len;

   opaque = vq->vdata[id];

   vring_detach(vq, id);

   vq->last_used_idx++;

   return opaque;
}

References BUG_ON, id, vring_used_elem::id, vring_virtqueue::last_used_idx, vring_used_elem::len, len, NULL, vring::num, vring_used::ring, vring::used, vring_virtqueue::vdata, vring_virtqueue::vring, vring_detach(), vring_more_used(), and wmb().

Referenced by virtnet_process_rx_packets(), and virtnet_process_tx_packets().

vring_add_buf()

void vring_add_buf	(	struct vring_virtqueue *	vq,
		struct vring_list	list[],
		unsigned int	out,
		unsigned int	in,
		void *	index,
		int	num_added
	)

Definition at line 86 of file virtio-ring.c.

{
   struct vring *vr = &vq->vring;
   int i, avail, head, prev;

   BUG_ON(out + in == 0);

   prev = 0;
   head = vq->free_head;
   for (i = head; out; i = vr->desc[i].next, out--) {

           vr->desc[i].flags = VRING_DESC_F_NEXT;
           vr->desc[i].addr = list->addr;
           vr->desc[i].len = list->length;
           prev = i;
           list++;
   }
   for ( ; in; i = vr->desc[i].next, in--) {

           vr->desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
           vr->desc[i].addr = list->addr;
           vr->desc[i].len = list->length;
           prev = i;
           list++;
   }
   vr->desc[prev].flags &= ~VRING_DESC_F_NEXT;

   vq->free_head = i;

   vq->vdata[head] = opaque;

   avail = (vr->avail->idx + num_added) % vr->num;
   vr->avail->ring[avail] = head;
   wmb();
}

References vring_desc::addr, vring_list::addr, vring::avail, BUG_ON, vring::desc, vring_desc::flags, vring_virtqueue::free_head, head, vring_avail::idx, in, vring_desc::len, vring_list::length, vring_desc::next, vring::num, out, vring_avail::ring, vring_virtqueue::vdata, vring_virtqueue::vring, VRING_DESC_F_NEXT, VRING_DESC_F_WRITE, and wmb().

Referenced by virtnet_enqueue_iob().

vring_kick()

void vring_kick	(	struct virtio_pci_modern_device *	vdev,
		unsigned int	ioaddr,
		struct vring_virtqueue *	vq,
		int	num_added
	)

Definition at line 125 of file virtio-ring.c.

{
   struct vring *vr = &vq->vring;

   wmb();
   vr->avail->idx += num_added;

   mb();
   if (!(vr->used->flags & VRING_USED_F_NO_NOTIFY)) {
           if (vdev) {
                   /* virtio 1.0 */
                   vpm_notify(vdev, vq);
           } else {
                   /* legacy virtio */
                   vp_notify(ioaddr, vq->queue_index);
           }
   }
}

References vring::avail, vring_used::flags, vring_avail::idx, ioaddr, mb(), vring_virtqueue::queue_index, vring::used, vp_notify(), vpm_notify(), vring_virtqueue::vring, VRING_USED_F_NO_NOTIFY, and wmb().

Referenced by virtnet_enqueue_iob().