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-rw-r--r--drivers/net/xenvirt/virtqueue.h273
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diff --git a/drivers/net/xenvirt/virtqueue.h b/drivers/net/xenvirt/virtqueue.h
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+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * 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.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "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 COPYRIGHT
+ * OWNER OR CONTRIBUTORS 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.
+ */
+
+#ifndef _VIRTQUEUE_H_
+#define _VIRTQUEUE_H_
+
+#include <stdint.h>
+#include <linux/virtio_ring.h>
+#include <linux/virtio_net.h>
+
+#include <rte_atomic.h>
+#include <rte_memory.h>
+#include <rte_memzone.h>
+#include <rte_mempool.h>
+
+#include "virtio_logs.h"
+
+struct rte_mbuf;
+
+/* The alignment to use between consumer and producer parts of vring. */
+#define VIRTIO_PCI_VRING_ALIGN 4096
+
+enum { VTNET_RQ = 0, VTNET_TQ = 1, VTNET_CQ = 2 };
+
+/**
+ * The maximum virtqueue size is 2^15. Use that value as the end of
+ * descriptor chain terminator since it will never be a valid index
+ * in the descriptor table. This is used to verify we are correctly
+ * handling vq_free_cnt.
+ */
+#define VQ_RING_DESC_CHAIN_END 32768
+
+#define VIRTQUEUE_MAX_NAME_SZ 32
+
+struct pmd_internals {
+ struct rte_eth_stats eth_stats;
+ int port_id;
+ int virtio_idx;
+};
+
+
+struct virtqueue {
+ char vq_name[VIRTQUEUE_MAX_NAME_SZ];
+ struct rte_mempool *mpool; /**< mempool for mbuf allocation */
+ uint16_t queue_id; /**< DPDK queue index. */
+ uint16_t vq_queue_index; /**< PCI queue index */
+ uint8_t port_id; /**< Device port identifier. */
+
+ void *vq_ring_virt_mem; /**< virtual address of vring*/
+ int vq_alignment;
+ int vq_ring_size;
+
+ struct vring vq_ring; /**< vring keeping desc, used and avail */
+ struct pmd_internals *internals; /**< virtio device internal info. */
+ uint16_t vq_nentries; /**< vring desc numbers */
+ uint16_t vq_desc_head_idx;
+ uint16_t vq_free_cnt; /**< num of desc available */
+ uint16_t vq_used_cons_idx; /**< Last consumed desc in used table, trails vq_ring.used->idx*/
+
+ struct vq_desc_extra {
+ void *cookie;
+ uint16_t ndescs;
+ } vq_descx[0] __rte_cache_aligned;
+};
+
+
+#ifdef RTE_LIBRTE_XENVIRT_DEBUG_DUMP
+#define VIRTQUEUE_DUMP(vq) do { \
+ uint16_t used_idx, nused; \
+ used_idx = (vq)->vq_ring.used->idx; \
+ nused = (uint16_t)(used_idx - (vq)->vq_used_cons_idx); \
+ PMD_INIT_LOG(DEBUG, \
+ "VQ: %s - size=%d; free=%d; used=%d; desc_head_idx=%d;" \
+ " avail.idx=%d; used_cons_idx=%d; used.idx=%d;" \
+ " avail.flags=0x%x; used.flags=0x%x\n", \
+ (vq)->vq_name, (vq)->vq_nentries, (vq)->vq_free_cnt, nused, \
+ (vq)->vq_desc_head_idx, (vq)->vq_ring.avail->idx, \
+ (vq)->vq_used_cons_idx, (vq)->vq_ring.used->idx, \
+ (vq)->vq_ring.avail->flags, (vq)->vq_ring.used->flags); \
+} while (0)
+#else
+#define VIRTQUEUE_DUMP(vq) do { } while (0)
+#endif
+
+
+/**
+ * Dump virtqueue internal structures, for debug purpose only.
+ */
+void virtqueue_dump(struct virtqueue *vq);
+
+/**
+ * Get all mbufs to be freed.
+ */
+struct rte_mbuf * virtqueue_detatch_unused(struct virtqueue *vq);
+
+static inline int __attribute__((always_inline))
+virtqueue_full(const struct virtqueue *vq)
+{
+ return vq->vq_free_cnt == 0;
+}
+
+#define VIRTQUEUE_NUSED(vq) ((uint16_t)((vq)->vq_ring.used->idx - (vq)->vq_used_cons_idx))
+
+static inline void __attribute__((always_inline))
+vq_ring_update_avail(struct virtqueue *vq, uint16_t desc_idx)
+{
+ uint16_t avail_idx;
+ /*
+ * Place the head of the descriptor chain into the next slot and make
+ * it usable to the host. The chain is made available now rather than
+ * deferring to virtqueue_notify() in the hopes that if the host is
+ * currently running on another CPU, we can keep it processing the new
+ * descriptor.
+ */
+ avail_idx = (uint16_t)(vq->vq_ring.avail->idx & (vq->vq_nentries - 1));
+ vq->vq_ring.avail->ring[avail_idx] = desc_idx;
+ rte_smp_wmb();
+ vq->vq_ring.avail->idx++;
+}
+
+static inline void __attribute__((always_inline))
+vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
+{
+ struct vring_desc *dp;
+ struct vq_desc_extra *dxp;
+
+ dp = &vq->vq_ring.desc[desc_idx];
+ dxp = &vq->vq_descx[desc_idx];
+ vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
+ while (dp->flags & VRING_DESC_F_NEXT) {
+ dp = &vq->vq_ring.desc[dp->next];
+ }
+ dxp->ndescs = 0;
+
+ /*
+ * We must append the existing free chain, if any, to the end of
+ * newly freed chain. If the virtqueue was completely used, then
+ * head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
+ */
+ dp->next = vq->vq_desc_head_idx;
+ vq->vq_desc_head_idx = desc_idx;
+}
+
+static inline int __attribute__((always_inline))
+virtqueue_enqueue_recv_refill(struct virtqueue *rxvq, struct rte_mbuf *cookie)
+{
+ const uint16_t needed = 1;
+ const uint16_t head_idx = rxvq->vq_desc_head_idx;
+ struct vring_desc *start_dp = rxvq->vq_ring.desc;
+ struct vq_desc_extra *dxp;
+
+ if (unlikely(rxvq->vq_free_cnt == 0))
+ return -ENOSPC;
+ if (unlikely(rxvq->vq_free_cnt < needed))
+ return -EMSGSIZE;
+ if (unlikely(head_idx >= rxvq->vq_nentries))
+ return -EFAULT;
+
+ dxp = &rxvq->vq_descx[head_idx];
+ dxp->cookie = (void *)cookie;
+ dxp->ndescs = needed;
+
+ start_dp[head_idx].addr =
+ (uint64_t) ((uintptr_t)cookie->buf_addr + RTE_PKTMBUF_HEADROOM - sizeof(struct virtio_net_hdr));
+ start_dp[head_idx].len = cookie->buf_len - RTE_PKTMBUF_HEADROOM + sizeof(struct virtio_net_hdr);
+ start_dp[head_idx].flags = VRING_DESC_F_WRITE;
+ rxvq->vq_desc_head_idx = start_dp[head_idx].next;
+ rxvq->vq_free_cnt = (uint16_t)(rxvq->vq_free_cnt - needed);
+ vq_ring_update_avail(rxvq, head_idx);
+
+ return 0;
+}
+
+static inline int __attribute__((always_inline))
+virtqueue_enqueue_xmit(struct virtqueue *txvq, struct rte_mbuf *cookie)
+{
+
+ const uint16_t needed = 2;
+ struct vring_desc *start_dp = txvq->vq_ring.desc;
+ uint16_t head_idx = txvq->vq_desc_head_idx;
+ uint16_t idx = head_idx;
+ struct vq_desc_extra *dxp;
+
+ if (unlikely(txvq->vq_free_cnt == 0))
+ return -ENOSPC;
+ if (unlikely(txvq->vq_free_cnt < needed))
+ return -EMSGSIZE;
+ if (unlikely(head_idx >= txvq->vq_nentries))
+ return -EFAULT;
+
+ dxp = &txvq->vq_descx[idx];
+ dxp->cookie = (void *)cookie;
+ dxp->ndescs = needed;
+
+ start_dp = txvq->vq_ring.desc;
+ start_dp[idx].addr = 0;
+/*
+ * TODO: save one desc here?
+ */
+ start_dp[idx].len = sizeof(struct virtio_net_hdr);
+ start_dp[idx].flags = VRING_DESC_F_NEXT;
+ start_dp[idx].addr = (uintptr_t)NULL;
+ idx = start_dp[idx].next;
+ start_dp[idx].addr = (uint64_t)rte_pktmbuf_mtod(cookie, uintptr_t);
+ start_dp[idx].len = cookie->data_len;
+ start_dp[idx].flags = 0;
+ idx = start_dp[idx].next;
+ txvq->vq_desc_head_idx = idx;
+ txvq->vq_free_cnt = (uint16_t)(txvq->vq_free_cnt - needed);
+ vq_ring_update_avail(txvq, head_idx);
+
+ return 0;
+}
+
+static inline uint16_t __attribute__((always_inline))
+virtqueue_dequeue_burst(struct virtqueue *vq, struct rte_mbuf **rx_pkts, uint32_t *len, uint16_t num)
+{
+ struct vring_used_elem *uep;
+ struct rte_mbuf *cookie;
+ uint16_t used_idx, desc_idx;
+ uint16_t i;
+ /* Caller does the check */
+ for (i = 0; i < num ; i ++) {
+ used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
+ uep = &vq->vq_ring.used->ring[used_idx];
+ desc_idx = (uint16_t) uep->id;
+ cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
+ if (unlikely(cookie == NULL)) {
+ PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u\n",
+ vq->vq_used_cons_idx);
+ RTE_LOG(ERR, PMD, "%s: inconsistent (%u, %u)\n", __func__, used_idx , desc_idx);
+ break;
+ }
+ len[i] = uep->len;
+ rx_pkts[i] = cookie;
+ vq->vq_used_cons_idx++;
+ vq_ring_free_chain(vq, desc_idx);
+ vq->vq_descx[desc_idx].cookie = NULL;
+ }
+ return i;
+}
+
+#endif /* _VIRTQUEUE_H_ */