drivers/net/virtio/virtqueue.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2015 Intel Corporation
   3  */
   4 #include <stdint.h>
   5
   6 #include <rte_mbuf.h>
   7
   8 #include "virtqueue.h"
   9 #include "virtio_logs.h"
  10 #include "virtio.h"
  11 #include "virtio_rxtx_simple.h"
  12
  13 /*
  14  * Two types of mbuf to be cleaned:
  15  * 1) mbuf that has been consumed by backend but not used by virtio.
  16  * 2) mbuf that hasn't been consued by backend.
  17  */
  18 struct rte_mbuf *
  19 virtqueue_detach_unused(struct virtqueue *vq)
  20 {
  21         struct rte_mbuf *cookie;
  22         struct virtio_hw *hw;
  23         uint16_t start, end;
  24         int type, idx;
  25
  26         if (vq == NULL)
  27                 return NULL;
  28
  29         hw = vq->hw;
  30         type = virtio_get_queue_type(hw, vq->vq_queue_index);
  31         start = vq->vq_avail_idx & (vq->vq_nentries - 1);
  32         end = (vq->vq_avail_idx + vq->vq_free_cnt) & (vq->vq_nentries - 1);
  33
  34         for (idx = 0; idx < vq->vq_nentries; idx++) {
  35                 if (hw->use_vec_rx && !virtio_with_packed_queue(hw) &&
  36                     type == VTNET_RQ) {
  37                         if (start <= end && idx >= start && idx < end)
  38                                 continue;
  39                         if (start > end && (idx >= start || idx < end))
  40                                 continue;
  41                         cookie = vq->sw_ring[idx];
  42                         if (cookie != NULL) {
  43                                 vq->sw_ring[idx] = NULL;
  44                                 return cookie;
  45                         }
  46                 } else {
  47                         cookie = vq->vq_descx[idx].cookie;
  48                         if (cookie != NULL) {
  49                                 vq->vq_descx[idx].cookie = NULL;
  50                                 return cookie;
  51                         }
  52                 }
  53         }
  54
  55         return NULL;
  56 }
  57
  58 /* Flush used descs */
  59 static void
  60 virtqueue_rxvq_flush_packed(struct virtqueue *vq)
  61 {
  62         struct vq_desc_extra *dxp;
  63         uint16_t i;
  64
  65         struct vring_packed_desc *descs = vq->vq_packed.ring.desc;
  66         int cnt = 0;
  67
  68         i = vq->vq_used_cons_idx;
  69         while (desc_is_used(&descs[i], vq) && cnt++ < vq->vq_nentries) {
  70                 dxp = &vq->vq_descx[descs[i].id];
  71                 if (dxp->cookie != NULL) {
  72                         rte_pktmbuf_free(dxp->cookie);
  73                         dxp->cookie = NULL;
  74                 }
  75                 vq->vq_free_cnt++;
  76                 vq->vq_used_cons_idx++;
  77                 if (vq->vq_used_cons_idx >= vq->vq_nentries) {
  78                         vq->vq_used_cons_idx -= vq->vq_nentries;
  79                         vq->vq_packed.used_wrap_counter ^= 1;
  80                 }
  81                 i = vq->vq_used_cons_idx;
  82         }
  83 }
  84
  85 /* Flush the elements in the used ring. */
  86 static void
  87 virtqueue_rxvq_flush_split(struct virtqueue *vq)
  88 {
  89         struct virtnet_rx *rxq = &vq->rxq;
  90         struct virtio_hw *hw = vq->hw;
  91         struct vring_used_elem *uep;
  92         struct vq_desc_extra *dxp;
  93         uint16_t used_idx, desc_idx;
  94         uint16_t nb_used, i;
  95
  96         nb_used = virtqueue_nused(vq);
  97
  98         for (i = 0; i < nb_used; i++) {
  99                 used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
 100                 uep = &vq->vq_split.ring.used->ring[used_idx];
 101                 if (hw->use_vec_rx) {
 102                         desc_idx = used_idx;
 103                         rte_pktmbuf_free(vq->sw_ring[desc_idx]);
 104                         vq->vq_free_cnt++;
 105                 } else if (hw->use_inorder_rx) {
 106                         desc_idx = (uint16_t)uep->id;
 107                         dxp = &vq->vq_descx[desc_idx];
 108                         if (dxp->cookie != NULL) {
 109                                 rte_pktmbuf_free(dxp->cookie);
 110                                 dxp->cookie = NULL;
 111                         }
 112                         vq_ring_free_inorder(vq, desc_idx, 1);
 113                 } else {
 114                         desc_idx = (uint16_t)uep->id;
 115                         dxp = &vq->vq_descx[desc_idx];
 116                         if (dxp->cookie != NULL) {
 117                                 rte_pktmbuf_free(dxp->cookie);
 118                                 dxp->cookie = NULL;
 119                         }
 120                         vq_ring_free_chain(vq, desc_idx);
 121                 }
 122                 vq->vq_used_cons_idx++;
 123         }
 124
 125         if (hw->use_vec_rx) {
 126                 while (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
 127                         virtio_rxq_rearm_vec(rxq);
 128                         if (virtqueue_kick_prepare(vq))
 129                                 virtqueue_notify(vq);
 130                 }
 131         }
 132 }
 133
 134 /* Flush the elements in the used ring. */
 135 void
 136 virtqueue_rxvq_flush(struct virtqueue *vq)
 137 {
 138         struct virtio_hw *hw = vq->hw;
 139
 140         if (virtio_with_packed_queue(hw))
 141                 virtqueue_rxvq_flush_packed(vq);
 142         else
 143                 virtqueue_rxvq_flush_split(vq);
 144 }
 145
 146 int
 147 virtqueue_rxvq_reset_packed(struct virtqueue *vq)
 148 {
 149         int size = vq->vq_nentries;
 150         struct vq_desc_extra *dxp;
 151         struct virtnet_rx *rxvq;
 152         uint16_t desc_idx;
 153
 154         vq->vq_used_cons_idx = 0;
 155         vq->vq_desc_head_idx = 0;
 156         vq->vq_avail_idx = 0;
 157         vq->vq_desc_tail_idx = (uint16_t)(vq->vq_nentries - 1);
 158         vq->vq_free_cnt = vq->vq_nentries;
 159
 160         vq->vq_packed.used_wrap_counter = 1;
 161         vq->vq_packed.cached_flags = VRING_PACKED_DESC_F_AVAIL;
 162         vq->vq_packed.event_flags_shadow = 0;
 163         vq->vq_packed.cached_flags |= VRING_DESC_F_WRITE;
 164
 165         rxvq = &vq->rxq;
 166         memset(rxvq->mz->addr, 0, rxvq->mz->len);
 167
 168         for (desc_idx = 0; desc_idx < vq->vq_nentries; desc_idx++) {
 169                 dxp = &vq->vq_descx[desc_idx];
 170                 if (dxp->cookie != NULL) {
 171                         rte_pktmbuf_free(dxp->cookie);
 172                         dxp->cookie = NULL;
 173                 }
 174         }
 175
 176         vring_desc_init_packed(vq, size);
 177
 178         virtqueue_disable_intr(vq);
 179         return 0;
 180 }
 181
 182 int
 183 virtqueue_txvq_reset_packed(struct virtqueue *vq)
 184 {
 185         int size = vq->vq_nentries;
 186         struct vq_desc_extra *dxp;
 187         struct virtnet_tx *txvq;
 188         uint16_t desc_idx;
 189         struct virtio_tx_region *txr;
 190         struct vring_packed_desc *start_dp;
 191
 192         vq->vq_used_cons_idx = 0;
 193         vq->vq_desc_head_idx = 0;
 194         vq->vq_avail_idx = 0;
 195         vq->vq_desc_tail_idx = (uint16_t)(vq->vq_nentries - 1);
 196         vq->vq_free_cnt = vq->vq_nentries;
 197
 198         vq->vq_packed.used_wrap_counter = 1;
 199         vq->vq_packed.cached_flags = VRING_PACKED_DESC_F_AVAIL;
 200         vq->vq_packed.event_flags_shadow = 0;
 201
 202         txvq = &vq->txq;
 203         txr = txvq->virtio_net_hdr_mz->addr;
 204         memset(txvq->mz->addr, 0, txvq->mz->len);
 205         memset(txvq->virtio_net_hdr_mz->addr, 0,
 206                 txvq->virtio_net_hdr_mz->len);
 207
 208         for (desc_idx = 0; desc_idx < vq->vq_nentries; desc_idx++) {
 209                 dxp = &vq->vq_descx[desc_idx];
 210                 if (dxp->cookie != NULL) {
 211                         rte_pktmbuf_free(dxp->cookie);
 212                         dxp->cookie = NULL;
 213                 }
 214
 215                 if (virtio_with_feature(vq->hw, VIRTIO_RING_F_INDIRECT_DESC)) {
 216                         /* first indirect descriptor is always the tx header */
 217                         start_dp = txr[desc_idx].tx_packed_indir;
 218                         vring_desc_init_indirect_packed(start_dp,
 219                                                         RTE_DIM(txr[desc_idx].tx_packed_indir));
 220                         start_dp->addr = txvq->virtio_net_hdr_mem
 221                                          + desc_idx * sizeof(*txr)
 222                                          + offsetof(struct virtio_tx_region, tx_hdr);
 223                         start_dp->len = vq->hw->vtnet_hdr_size;
 224                 }
 225         }
 226
 227         vring_desc_init_packed(vq, size);
 228
 229         virtqueue_disable_intr(vq);
 230         return 0;
 231 }