Imported Upstream version 16.04

Change-Id: I77eadcd8538a9122e4773cbe55b24033dc451757
Signed-off-by: C.J. Collier <cjcollier@linuxfoundation.org>

1 files changed, 273 insertions, 0 deletions

diff --git a/drivers/net/xenvirt/virtqueue.h b/drivers/net/xenvirt/virtqueue.h
new file mode 100644
index 00000000..350eae3e
--- /dev/null
+++ b/drivers/net/xenvirt/virtqueue.h
@@ -0,0 +1,273 @@
+/*-
+ *   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_ */