lib/virtio/virtqueue.c

44  * information not stored with the vring structure
53     /* vring  information */
54     struct vring vring;             ///< vring data structure
55     struct capref vring_cap;        ///< capability of the vring data structure
56     lvaddr_t vring_vaddr;           ///< virtual address of the vring in memory
57     lpaddr_t vring_paddr;           ///< physical address of the vring
58     lvaddr_t vring_align;           ///< the alignment of the vring
60     uint16_t desc_num;              ///< number of descriptors of this vring
108         uint16_t *used_event = vring_get_used_event(&vq->vring);
111         vq->vring.avail->flags &= ~VIRTIO_RING_AVAIL_F_NO_INTERRUPT;
124  * \brief initializes the vring structure of the virtqueue
126  * \param vq virtqueue of the vring to initialize
130     struct vring *vr = &vq->vring;
137      * initialize the vring structure in memory
185         new = vq->vring.avail->idx;
187         event_idx = vring_get_avail_event(&vq->vring);
192     return ((vq->vring.used->flags & VIRTIO_RING_USED_F_NO_NOTIFY) == 0);
249     VIRTIO_DEBUG_VQ("Allocated memory for vring: [0x%lx & 0x%lx]\n",
269  * \param vring_cap capability to be used for the vring
414  * \brief Returns the physical address of the vring.
418  * \returns the physical address of the vring
426  * \brief returns the alignment of the vring
430  * \returns vring alignment
438  * \brief Returns the frame capability of the vring
488  * \brief Returns the number of elements (number of descriptors)in the vring of
493  * \returns number of elements in the vring
549     num_used = vq->vring.used->idx - vq->used_tail;
573     if (vq->used_tail == vq->vring.used->idx) {
621     uint16_t ndesc = vq->vring.avail->idx - vq->used_tail;
645         uint16_t *used_event = vring_get_used_event(&vq->vring);
648         vq->vring.avail->flags |= VIRTIO_RING_AVAIL_F_NO_INTERRUPT;
668  * We layout the vring structure in memory as follows:
670  * struct vring {
692  * \brief Maps the given capability and initializes the vring on the memory
695  * \param vr    pointer to the vring structure to be initialized
697  * \param align alignment constraints for the vring
703 errval_t vring_init_from_cap(struct vring *vr,
738  * \brief allocates a new vring structure
740  * \param vr        pointer to the vring structure
742  * \param align     the alignment constraints for the vring
748 errval_t vring_alloc(struct vring *vr,
779  * \brief frees the resources used by the vring structure
781  * \param vr the vring to be freed
786 errval_t vring_free(struct vring *vr)
814     uint16_t avail_idx = vq->vring.avail->idx & (vq->desc_num - 1);
815     vq->vring.avail->ring[avail_idx] = idx;
822                     vq->queue_index, vq->vring.avail->idx + 1, vq->desc_num_queued + 1);
824     vq->vring.avail->idx++;
848     struct vring_desc *desc = vq->vring.desc;
985     desc = &vq->vring.desc[desc_idx];
995             desc = &vq->vring.desc[desc->next];
1036     if (vq->used_tail == vq->vring.used->idx) {
1041     elem = &vq->vring.used->ring[used_idx];