Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 4809 insertions, 0 deletions

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
new file mode 100644
index 0000000000..deb2229ab4
--- /dev/null
+++ b/drivers/net/virtio_net.c
@@ -0,0 +1,4809 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* A network driver using virtio.
+ *
+ * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
+ */
+//#define DEBUG
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/module.h>
+#include <linux/virtio.h>
+#include <linux/virtio_net.h>
+#include <linux/bpf.h>
+#include <linux/bpf_trace.h>
+#include <linux/scatterlist.h>
+#include <linux/if_vlan.h>
+#include <linux/slab.h>
+#include <linux/cpu.h>
+#include <linux/average.h>
+#include <linux/filter.h>
+#include <linux/kernel.h>
+#include <net/route.h>
+#include <net/xdp.h>
+#include <net/net_failover.h>
+#include <net/netdev_rx_queue.h>
+
+static int napi_weight = NAPI_POLL_WEIGHT;
+module_param(napi_weight, int, 0444);
+
+static bool csum = true, gso = true, napi_tx = true;
+module_param(csum, bool, 0444);
+module_param(gso, bool, 0444);
+module_param(napi_tx, bool, 0644);
+
+/* FIXME: MTU in config. */
+#define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
+#define GOOD_COPY_LEN	128
+
+#define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
+
+/* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
+#define VIRTIO_XDP_HEADROOM 256
+
+/* Separating two types of XDP xmit */
+#define VIRTIO_XDP_TX		BIT(0)
+#define VIRTIO_XDP_REDIR	BIT(1)
+
+#define VIRTIO_XDP_FLAG	BIT(0)
+
+/* RX packet size EWMA. The average packet size is used to determine the packet
+ * buffer size when refilling RX rings. As the entire RX ring may be refilled
+ * at once, the weight is chosen so that the EWMA will be insensitive to short-
+ * term, transient changes in packet size.
+ */
+DECLARE_EWMA(pkt_len, 0, 64)
+
+#define VIRTNET_DRIVER_VERSION "1.0.0"
+
+static const unsigned long guest_offloads[] = {
+	VIRTIO_NET_F_GUEST_TSO4,
+	VIRTIO_NET_F_GUEST_TSO6,
+	VIRTIO_NET_F_GUEST_ECN,
+	VIRTIO_NET_F_GUEST_UFO,
+	VIRTIO_NET_F_GUEST_CSUM,
+	VIRTIO_NET_F_GUEST_USO4,
+	VIRTIO_NET_F_GUEST_USO6,
+	VIRTIO_NET_F_GUEST_HDRLEN
+};
+
+#define GUEST_OFFLOAD_GRO_HW_MASK ((1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
+				(1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
+				(1ULL << VIRTIO_NET_F_GUEST_ECN)  | \
+				(1ULL << VIRTIO_NET_F_GUEST_UFO)  | \
+				(1ULL << VIRTIO_NET_F_GUEST_USO4) | \
+				(1ULL << VIRTIO_NET_F_GUEST_USO6))
+
+struct virtnet_stat_desc {
+	char desc[ETH_GSTRING_LEN];
+	size_t offset;
+};
+
+struct virtnet_sq_stats {
+	struct u64_stats_sync syncp;
+	u64_stats_t packets;
+	u64_stats_t bytes;
+	u64_stats_t xdp_tx;
+	u64_stats_t xdp_tx_drops;
+	u64_stats_t kicks;
+	u64_stats_t tx_timeouts;
+};
+
+struct virtnet_rq_stats {
+	struct u64_stats_sync syncp;
+	u64_stats_t packets;
+	u64_stats_t bytes;
+	u64_stats_t drops;
+	u64_stats_t xdp_packets;
+	u64_stats_t xdp_tx;
+	u64_stats_t xdp_redirects;
+	u64_stats_t xdp_drops;
+	u64_stats_t kicks;
+};
+
+#define VIRTNET_SQ_STAT(m)	offsetof(struct virtnet_sq_stats, m)
+#define VIRTNET_RQ_STAT(m)	offsetof(struct virtnet_rq_stats, m)
+
+static const struct virtnet_stat_desc virtnet_sq_stats_desc[] = {
+	{ "packets",		VIRTNET_SQ_STAT(packets) },
+	{ "bytes",		VIRTNET_SQ_STAT(bytes) },
+	{ "xdp_tx",		VIRTNET_SQ_STAT(xdp_tx) },
+	{ "xdp_tx_drops",	VIRTNET_SQ_STAT(xdp_tx_drops) },
+	{ "kicks",		VIRTNET_SQ_STAT(kicks) },
+	{ "tx_timeouts",	VIRTNET_SQ_STAT(tx_timeouts) },
+};
+
+static const struct virtnet_stat_desc virtnet_rq_stats_desc[] = {
+	{ "packets",		VIRTNET_RQ_STAT(packets) },
+	{ "bytes",		VIRTNET_RQ_STAT(bytes) },
+	{ "drops",		VIRTNET_RQ_STAT(drops) },
+	{ "xdp_packets",	VIRTNET_RQ_STAT(xdp_packets) },
+	{ "xdp_tx",		VIRTNET_RQ_STAT(xdp_tx) },
+	{ "xdp_redirects",	VIRTNET_RQ_STAT(xdp_redirects) },
+	{ "xdp_drops",		VIRTNET_RQ_STAT(xdp_drops) },
+	{ "kicks",		VIRTNET_RQ_STAT(kicks) },
+};
+
+#define VIRTNET_SQ_STATS_LEN	ARRAY_SIZE(virtnet_sq_stats_desc)
+#define VIRTNET_RQ_STATS_LEN	ARRAY_SIZE(virtnet_rq_stats_desc)
+
+struct virtnet_interrupt_coalesce {
+	u32 max_packets;
+	u32 max_usecs;
+};
+
+/* The dma information of pages allocated at a time. */
+struct virtnet_rq_dma {
+	dma_addr_t addr;
+	u32 ref;
+	u16 len;
+	u16 need_sync;
+};
+
+/* Internal representation of a send virtqueue */
+struct send_queue {
+	/* Virtqueue associated with this send _queue */
+	struct virtqueue *vq;
+
+	/* TX: fragments + linear part + virtio header */
+	struct scatterlist sg[MAX_SKB_FRAGS + 2];
+
+	/* Name of the send queue: output.$index */
+	char name[16];
+
+	struct virtnet_sq_stats stats;
+
+	struct virtnet_interrupt_coalesce intr_coal;
+
+	struct napi_struct napi;
+
+	/* Record whether sq is in reset state. */
+	bool reset;
+};
+
+/* Internal representation of a receive virtqueue */
+struct receive_queue {
+	/* Virtqueue associated with this receive_queue */
+	struct virtqueue *vq;
+
+	struct napi_struct napi;
+
+	struct bpf_prog __rcu *xdp_prog;
+
+	struct virtnet_rq_stats stats;
+
+	struct virtnet_interrupt_coalesce intr_coal;
+
+	/* Chain pages by the private ptr. */
+	struct page *pages;
+
+	/* Average packet length for mergeable receive buffers. */
+	struct ewma_pkt_len mrg_avg_pkt_len;
+
+	/* Page frag for packet buffer allocation. */
+	struct page_frag alloc_frag;
+
+	/* RX: fragments + linear part + virtio header */
+	struct scatterlist sg[MAX_SKB_FRAGS + 2];
+
+	/* Min single buffer size for mergeable buffers case. */
+	unsigned int min_buf_len;
+
+	/* Name of this receive queue: input.$index */
+	char name[16];
+
+	struct xdp_rxq_info xdp_rxq;
+
+	/* Record the last dma info to free after new pages is allocated. */
+	struct virtnet_rq_dma *last_dma;
+
+	/* Do dma by self */
+	bool do_dma;
+};
+
+/* This structure can contain rss message with maximum settings for indirection table and keysize
+ * Note, that default structure that describes RSS configuration virtio_net_rss_config
+ * contains same info but can't handle table values.
+ * In any case, structure would be passed to virtio hw through sg_buf split by parts
+ * because table sizes may be differ according to the device configuration.
+ */
+#define VIRTIO_NET_RSS_MAX_KEY_SIZE     40
+#define VIRTIO_NET_RSS_MAX_TABLE_LEN    128
+struct virtio_net_ctrl_rss {
+	u32 hash_types;
+	u16 indirection_table_mask;
+	u16 unclassified_queue;
+	u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN];
+	u16 max_tx_vq;
+	u8 hash_key_length;
+	u8 key[VIRTIO_NET_RSS_MAX_KEY_SIZE];
+};
+
+/* Control VQ buffers: protected by the rtnl lock */
+struct control_buf {
+	struct virtio_net_ctrl_hdr hdr;
+	virtio_net_ctrl_ack status;
+	struct virtio_net_ctrl_mq mq;
+	u8 promisc;
+	u8 allmulti;
+	__virtio16 vid;
+	__virtio64 offloads;
+	struct virtio_net_ctrl_rss rss;
+	struct virtio_net_ctrl_coal_tx coal_tx;
+	struct virtio_net_ctrl_coal_rx coal_rx;
+	struct virtio_net_ctrl_coal_vq coal_vq;
+};
+
+struct virtnet_info {
+	struct virtio_device *vdev;
+	struct virtqueue *cvq;
+	struct net_device *dev;
+	struct send_queue *sq;
+	struct receive_queue *rq;
+	unsigned int status;
+
+	/* Max # of queue pairs supported by the device */
+	u16 max_queue_pairs;
+
+	/* # of queue pairs currently used by the driver */
+	u16 curr_queue_pairs;
+
+	/* # of XDP queue pairs currently used by the driver */
+	u16 xdp_queue_pairs;
+
+	/* xdp_queue_pairs may be 0, when xdp is already loaded. So add this. */
+	bool xdp_enabled;
+
+	/* I like... big packets and I cannot lie! */
+	bool big_packets;
+
+	/* number of sg entries allocated for big packets */
+	unsigned int big_packets_num_skbfrags;
+
+	/* Host will merge rx buffers for big packets (shake it! shake it!) */
+	bool mergeable_rx_bufs;
+
+	/* Host supports rss and/or hash report */
+	bool has_rss;
+	bool has_rss_hash_report;
+	u8 rss_key_size;
+	u16 rss_indir_table_size;
+	u32 rss_hash_types_supported;
+	u32 rss_hash_types_saved;
+
+	/* Has control virtqueue */
+	bool has_cvq;
+
+	/* Host can handle any s/g split between our header and packet data */
+	bool any_header_sg;
+
+	/* Packet virtio header size */
+	u8 hdr_len;
+
+	/* Work struct for delayed refilling if we run low on memory. */
+	struct delayed_work refill;
+
+	/* Is delayed refill enabled? */
+	bool refill_enabled;
+
+	/* The lock to synchronize the access to refill_enabled */
+	spinlock_t refill_lock;
+
+	/* Work struct for config space updates */
+	struct work_struct config_work;
+
+	/* Does the affinity hint is set for virtqueues? */
+	bool affinity_hint_set;
+
+	/* CPU hotplug instances for online & dead */
+	struct hlist_node node;
+	struct hlist_node node_dead;
+
+	struct control_buf *ctrl;
+
+	/* Ethtool settings */
+	u8 duplex;
+	u32 speed;
+
+	/* Interrupt coalescing settings */
+	struct virtnet_interrupt_coalesce intr_coal_tx;
+	struct virtnet_interrupt_coalesce intr_coal_rx;
+
+	unsigned long guest_offloads;
+	unsigned long guest_offloads_capable;
+
+	/* failover when STANDBY feature enabled */
+	struct failover *failover;
+};
+
+struct padded_vnet_hdr {
+	struct virtio_net_hdr_v1_hash hdr;
+	/*
+	 * hdr is in a separate sg buffer, and data sg buffer shares same page
+	 * with this header sg. This padding makes next sg 16 byte aligned
+	 * after the header.
+	 */
+	char padding[12];
+};
+
+struct virtio_net_common_hdr {
+	union {
+		struct virtio_net_hdr hdr;
+		struct virtio_net_hdr_mrg_rxbuf	mrg_hdr;
+		struct virtio_net_hdr_v1_hash hash_v1_hdr;
+	};
+};
+
+static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf);
+
+static bool is_xdp_frame(void *ptr)
+{
+	return (unsigned long)ptr & VIRTIO_XDP_FLAG;
+}
+
+static void *xdp_to_ptr(struct xdp_frame *ptr)
+{
+	return (void *)((unsigned long)ptr | VIRTIO_XDP_FLAG);
+}
+
+static struct xdp_frame *ptr_to_xdp(void *ptr)
+{
+	return (struct xdp_frame *)((unsigned long)ptr & ~VIRTIO_XDP_FLAG);
+}
+
+/* Converting between virtqueue no. and kernel tx/rx queue no.
+ * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
+ */
+static int vq2txq(struct virtqueue *vq)
+{
+	return (vq->index - 1) / 2;
+}
+
+static int txq2vq(int txq)
+{
+	return txq * 2 + 1;
+}
+
+static int vq2rxq(struct virtqueue *vq)
+{
+	return vq->index / 2;
+}
+
+static int rxq2vq(int rxq)
+{
+	return rxq * 2;
+}
+
+static inline struct virtio_net_common_hdr *
+skb_vnet_common_hdr(struct sk_buff *skb)
+{
+	return (struct virtio_net_common_hdr *)skb->cb;
+}
+
+/*
+ * private is used to chain pages for big packets, put the whole
+ * most recent used list in the beginning for reuse
+ */
+static void give_pages(struct receive_queue *rq, struct page *page)
+{
+	struct page *end;
+
+	/* Find end of list, sew whole thing into vi->rq.pages. */
+	for (end = page; end->private; end = (struct page *)end->private);
+	end->private = (unsigned long)rq->pages;
+	rq->pages = page;
+}
+
+static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
+{
+	struct page *p = rq->pages;
+
+	if (p) {
+		rq->pages = (struct page *)p->private;
+		/* clear private here, it is used to chain pages */
+		p->private = 0;
+	} else
+		p = alloc_page(gfp_mask);
+	return p;
+}
+
+static void virtnet_rq_free_buf(struct virtnet_info *vi,
+				struct receive_queue *rq, void *buf)
+{
+	if (vi->mergeable_rx_bufs)
+		put_page(virt_to_head_page(buf));
+	else if (vi->big_packets)
+		give_pages(rq, buf);
+	else
+		put_page(virt_to_head_page(buf));
+}
+
+static void enable_delayed_refill(struct virtnet_info *vi)
+{
+	spin_lock_bh(&vi->refill_lock);
+	vi->refill_enabled = true;
+	spin_unlock_bh(&vi->refill_lock);
+}
+
+static void disable_delayed_refill(struct virtnet_info *vi)
+{
+	spin_lock_bh(&vi->refill_lock);
+	vi->refill_enabled = false;
+	spin_unlock_bh(&vi->refill_lock);
+}
+
+static void virtqueue_napi_schedule(struct napi_struct *napi,
+				    struct virtqueue *vq)
+{
+	if (napi_schedule_prep(napi)) {
+		virtqueue_disable_cb(vq);
+		__napi_schedule(napi);
+	}
+}
+
+static void virtqueue_napi_complete(struct napi_struct *napi,
+				    struct virtqueue *vq, int processed)
+{
+	int opaque;
+
+	opaque = virtqueue_enable_cb_prepare(vq);
+	if (napi_complete_done(napi, processed)) {
+		if (unlikely(virtqueue_poll(vq, opaque)))
+			virtqueue_napi_schedule(napi, vq);
+	} else {
+		virtqueue_disable_cb(vq);
+	}
+}
+
+static void skb_xmit_done(struct virtqueue *vq)
+{
+	struct virtnet_info *vi = vq->vdev->priv;
+	struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
+
+	/* Suppress further interrupts. */
+	virtqueue_disable_cb(vq);
+
+	if (napi->weight)
+		virtqueue_napi_schedule(napi, vq);
+	else
+		/* We were probably waiting for more output buffers. */
+		netif_wake_subqueue(vi->dev, vq2txq(vq));
+}
+
+#define MRG_CTX_HEADER_SHIFT 22
+static void *mergeable_len_to_ctx(unsigned int truesize,
+				  unsigned int headroom)
+{
+	return (void *)(unsigned long)((headroom << MRG_CTX_HEADER_SHIFT) | truesize);
+}
+
+static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx)
+{
+	return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT;
+}
+
+static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx)
+{
+	return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1);
+}
+
+static struct sk_buff *virtnet_build_skb(void *buf, unsigned int buflen,
+					 unsigned int headroom,
+					 unsigned int len)
+{
+	struct sk_buff *skb;
+
+	skb = build_skb(buf, buflen);
+	if (unlikely(!skb))
+		return NULL;
+
+	skb_reserve(skb, headroom);
+	skb_put(skb, len);
+
+	return skb;
+}
+
+/* Called from bottom half context */
+static struct sk_buff *page_to_skb(struct virtnet_info *vi,
+				   struct receive_queue *rq,
+				   struct page *page, unsigned int offset,
+				   unsigned int len, unsigned int truesize,
+				   unsigned int headroom)
+{
+	struct sk_buff *skb;
+	struct virtio_net_common_hdr *hdr;
+	unsigned int copy, hdr_len, hdr_padded_len;
+	struct page *page_to_free = NULL;
+	int tailroom, shinfo_size;
+	char *p, *hdr_p, *buf;
+
+	p = page_address(page) + offset;
+	hdr_p = p;
+
+	hdr_len = vi->hdr_len;
+	if (vi->mergeable_rx_bufs)
+		hdr_padded_len = hdr_len;
+	else
+		hdr_padded_len = sizeof(struct padded_vnet_hdr);
+
+	buf = p - headroom;
+	len -= hdr_len;
+	offset += hdr_padded_len;
+	p += hdr_padded_len;
+	tailroom = truesize - headroom  - hdr_padded_len - len;
+
+	shinfo_size = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+
+	/* copy small packet so we can reuse these pages */
+	if (!NET_IP_ALIGN && len > GOOD_COPY_LEN && tailroom >= shinfo_size) {
+		skb = virtnet_build_skb(buf, truesize, p - buf, len);
+		if (unlikely(!skb))
+			return NULL;
+
+		page = (struct page *)page->private;
+		if (page)
+			give_pages(rq, page);
+		goto ok;
+	}
+
+	/* copy small packet so we can reuse these pages for small data */
+	skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
+	if (unlikely(!skb))
+		return NULL;
+
+	/* Copy all frame if it fits skb->head, otherwise
+	 * we let virtio_net_hdr_to_skb() and GRO pull headers as needed.
+	 */
+	if (len <= skb_tailroom(skb))
+		copy = len;
+	else
+		copy = ETH_HLEN;
+	skb_put_data(skb, p, copy);
+
+	len -= copy;
+	offset += copy;
+
+	if (vi->mergeable_rx_bufs) {
+		if (len)
+			skb_add_rx_frag(skb, 0, page, offset, len, truesize);
+		else
+			page_to_free = page;
+		goto ok;
+	}
+
+	/*
+	 * Verify that we can indeed put this data into a skb.
+	 * This is here to handle cases when the device erroneously
+	 * tries to receive more than is possible. This is usually
+	 * the case of a broken device.
+	 */
+	if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
+		net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
+		dev_kfree_skb(skb);
+		return NULL;
+	}
+	BUG_ON(offset >= PAGE_SIZE);
+	while (len) {
+		unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
+		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
+				frag_size, truesize);
+		len -= frag_size;
+		page = (struct page *)page->private;
+		offset = 0;
+	}
+
+	if (page)
+		give_pages(rq, page);
+
+ok:
+	hdr = skb_vnet_common_hdr(skb);
+	memcpy(hdr, hdr_p, hdr_len);
+	if (page_to_free)
+		put_page(page_to_free);
+
+	return skb;
+}
+
+static void virtnet_rq_unmap(struct receive_queue *rq, void *buf, u32 len)
+{
+	struct page *page = virt_to_head_page(buf);
+	struct virtnet_rq_dma *dma;
+	void *head;
+	int offset;
+
+	head = page_address(page);
+
+	dma = head;
+
+	--dma->ref;
+
+	if (dma->need_sync && len) {
+		offset = buf - (head + sizeof(*dma));
+
+		virtqueue_dma_sync_single_range_for_cpu(rq->vq, dma->addr,
+							offset, len,
+							DMA_FROM_DEVICE);
+	}
+
+	if (dma->ref)
+		return;
+
+	virtqueue_dma_unmap_single_attrs(rq->vq, dma->addr, dma->len,
+					 DMA_FROM_DEVICE, DMA_ATTR_SKIP_CPU_SYNC);
+	put_page(page);
+}
+
+static void *virtnet_rq_get_buf(struct receive_queue *rq, u32 *len, void **ctx)
+{
+	void *buf;
+
+	buf = virtqueue_get_buf_ctx(rq->vq, len, ctx);
+	if (buf && rq->do_dma)
+		virtnet_rq_unmap(rq, buf, *len);
+
+	return buf;
+}
+
+static void virtnet_rq_init_one_sg(struct receive_queue *rq, void *buf, u32 len)
+{
+	struct virtnet_rq_dma *dma;
+	dma_addr_t addr;
+	u32 offset;
+	void *head;
+
+	if (!rq->do_dma) {
+		sg_init_one(rq->sg, buf, len);
+		return;
+	}
+
+	head = page_address(rq->alloc_frag.page);
+
+	offset = buf - head;
+
+	dma = head;
+
+	addr = dma->addr - sizeof(*dma) + offset;
+
+	sg_init_table(rq->sg, 1);
+	rq->sg[0].dma_address = addr;
+	rq->sg[0].length = len;
+}
+
+static void *virtnet_rq_alloc(struct receive_queue *rq, u32 size, gfp_t gfp)
+{
+	struct page_frag *alloc_frag = &rq->alloc_frag;
+	struct virtnet_rq_dma *dma;
+	void *buf, *head;
+	dma_addr_t addr;
+
+	if (unlikely(!skb_page_frag_refill(size, alloc_frag, gfp)))
+		return NULL;
+
+	head = page_address(alloc_frag->page);
+
+	if (rq->do_dma) {
+		dma = head;
+
+		/* new pages */
+		if (!alloc_frag->offset) {
+			if (rq->last_dma) {
+				/* Now, the new page is allocated, the last dma
+				 * will not be used. So the dma can be unmapped
+				 * if the ref is 0.
+				 */
+				virtnet_rq_unmap(rq, rq->last_dma, 0);
+				rq->last_dma = NULL;
+			}
+
+			dma->len = alloc_frag->size - sizeof(*dma);
+
+			addr = virtqueue_dma_map_single_attrs(rq->vq, dma + 1,
+							      dma->len, DMA_FROM_DEVICE, 0);
+			if (virtqueue_dma_mapping_error(rq->vq, addr))
+				return NULL;
+
+			dma->addr = addr;
+			dma->need_sync = virtqueue_dma_need_sync(rq->vq, addr);
+
+			/* Add a reference to dma to prevent the entire dma from
+			 * being released during error handling. This reference
+			 * will be freed after the pages are no longer used.
+			 */
+			get_page(alloc_frag->page);
+			dma->ref = 1;
+			alloc_frag->offset = sizeof(*dma);
+
+			rq->last_dma = dma;
+		}
+
+		++dma->ref;
+	}
+
+	buf = head + alloc_frag->offset;
+
+	get_page(alloc_frag->page);
+	alloc_frag->offset += size;
+
+	return buf;
+}
+
+static void virtnet_rq_set_premapped(struct virtnet_info *vi)
+{
+	int i;
+
+	/* disable for big mode */
+	if (!vi->mergeable_rx_bufs && vi->big_packets)
+		return;
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		if (virtqueue_set_dma_premapped(vi->rq[i].vq))
+			continue;
+
+		vi->rq[i].do_dma = true;
+	}
+}
+
+static void virtnet_rq_unmap_free_buf(struct virtqueue *vq, void *buf)
+{
+	struct virtnet_info *vi = vq->vdev->priv;
+	struct receive_queue *rq;
+	int i = vq2rxq(vq);
+
+	rq = &vi->rq[i];
+
+	if (rq->do_dma)
+		virtnet_rq_unmap(rq, buf, 0);
+
+	virtnet_rq_free_buf(vi, rq, buf);
+}
+
+static void free_old_xmit_skbs(struct send_queue *sq, bool in_napi)
+{
+	unsigned int len;
+	unsigned int packets = 0;
+	unsigned int bytes = 0;
+	void *ptr;
+
+	while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
+		if (likely(!is_xdp_frame(ptr))) {
+			struct sk_buff *skb = ptr;
+
+			pr_debug("Sent skb %p\n", skb);
+
+			bytes += skb->len;
+			napi_consume_skb(skb, in_napi);
+		} else {
+			struct xdp_frame *frame = ptr_to_xdp(ptr);
+
+			bytes += xdp_get_frame_len(frame);
+			xdp_return_frame(frame);
+		}
+		packets++;
+	}
+
+	/* Avoid overhead when no packets have been processed
+	 * happens when called speculatively from start_xmit.
+	 */
+	if (!packets)
+		return;
+
+	u64_stats_update_begin(&sq->stats.syncp);
+	u64_stats_add(&sq->stats.bytes, bytes);
+	u64_stats_add(&sq->stats.packets, packets);
+	u64_stats_update_end(&sq->stats.syncp);
+}
+
+static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
+{
+	if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
+		return false;
+	else if (q < vi->curr_queue_pairs)
+		return true;
+	else
+		return false;
+}
+
+static void check_sq_full_and_disable(struct virtnet_info *vi,
+				      struct net_device *dev,
+				      struct send_queue *sq)
+{
+	bool use_napi = sq->napi.weight;
+	int qnum;
+
+	qnum = sq - vi->sq;
+
+	/* If running out of space, stop queue to avoid getting packets that we
+	 * are then unable to transmit.
+	 * An alternative would be to force queuing layer to requeue the skb by
+	 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
+	 * returned in a normal path of operation: it means that driver is not
+	 * maintaining the TX queue stop/start state properly, and causes
+	 * the stack to do a non-trivial amount of useless work.
+	 * Since most packets only take 1 or 2 ring slots, stopping the queue
+	 * early means 16 slots are typically wasted.
+	 */
+	if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
+		netif_stop_subqueue(dev, qnum);
+		if (use_napi) {
+			if (unlikely(!virtqueue_enable_cb_delayed(sq->vq)))
+				virtqueue_napi_schedule(&sq->napi, sq->vq);
+		} else if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
+			/* More just got used, free them then recheck. */
+			free_old_xmit_skbs(sq, false);
+			if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
+				netif_start_subqueue(dev, qnum);
+				virtqueue_disable_cb(sq->vq);
+			}
+		}
+	}
+}
+
+static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
+				   struct send_queue *sq,
+				   struct xdp_frame *xdpf)
+{
+	struct virtio_net_hdr_mrg_rxbuf *hdr;
+	struct skb_shared_info *shinfo;
+	u8 nr_frags = 0;
+	int err, i;
+
+	if (unlikely(xdpf->headroom < vi->hdr_len))
+		return -EOVERFLOW;
+
+	if (unlikely(xdp_frame_has_frags(xdpf))) {
+		shinfo = xdp_get_shared_info_from_frame(xdpf);
+		nr_frags = shinfo->nr_frags;
+	}
+
+	/* In wrapping function virtnet_xdp_xmit(), we need to free
+	 * up the pending old buffers, where we need to calculate the
+	 * position of skb_shared_info in xdp_get_frame_len() and
+	 * xdp_return_frame(), which will involve to xdpf->data and
+	 * xdpf->headroom. Therefore, we need to update the value of
+	 * headroom synchronously here.
+	 */
+	xdpf->headroom -= vi->hdr_len;
+	xdpf->data -= vi->hdr_len;
+	/* Zero header and leave csum up to XDP layers */
+	hdr = xdpf->data;
+	memset(hdr, 0, vi->hdr_len);
+	xdpf->len   += vi->hdr_len;
+
+	sg_init_table(sq->sg, nr_frags + 1);
+	sg_set_buf(sq->sg, xdpf->data, xdpf->len);
+	for (i = 0; i < nr_frags; i++) {
+		skb_frag_t *frag = &shinfo->frags[i];
+
+		sg_set_page(&sq->sg[i + 1], skb_frag_page(frag),
+			    skb_frag_size(frag), skb_frag_off(frag));
+	}
+
+	err = virtqueue_add_outbuf(sq->vq, sq->sg, nr_frags + 1,
+				   xdp_to_ptr(xdpf), GFP_ATOMIC);
+	if (unlikely(err))
+		return -ENOSPC; /* Caller handle free/refcnt */
+
+	return 0;
+}
+
+/* when vi->curr_queue_pairs > nr_cpu_ids, the txq/sq is only used for xdp tx on
+ * the current cpu, so it does not need to be locked.
+ *
+ * Here we use marco instead of inline functions because we have to deal with
+ * three issues at the same time: 1. the choice of sq. 2. judge and execute the
+ * lock/unlock of txq 3. make sparse happy. It is difficult for two inline
+ * functions to perfectly solve these three problems at the same time.
+ */
+#define virtnet_xdp_get_sq(vi) ({                                       \
+	int cpu = smp_processor_id();                                   \
+	struct netdev_queue *txq;                                       \
+	typeof(vi) v = (vi);                                            \
+	unsigned int qp;                                                \
+									\
+	if (v->curr_queue_pairs > nr_cpu_ids) {                         \
+		qp = v->curr_queue_pairs - v->xdp_queue_pairs;          \
+		qp += cpu;                                              \
+		txq = netdev_get_tx_queue(v->dev, qp);                  \
+		__netif_tx_acquire(txq);                                \
+	} else {                                                        \
+		qp = cpu % v->curr_queue_pairs;                         \
+		txq = netdev_get_tx_queue(v->dev, qp);                  \
+		__netif_tx_lock(txq, cpu);                              \
+	}                                                               \
+	v->sq + qp;                                                     \
+})
+
+#define virtnet_xdp_put_sq(vi, q) {                                     \
+	struct netdev_queue *txq;                                       \
+	typeof(vi) v = (vi);                                            \
+									\
+	txq = netdev_get_tx_queue(v->dev, (q) - v->sq);                 \
+	if (v->curr_queue_pairs > nr_cpu_ids)                           \
+		__netif_tx_release(txq);                                \
+	else                                                            \
+		__netif_tx_unlock(txq);                                 \
+}
+
+static int virtnet_xdp_xmit(struct net_device *dev,
+			    int n, struct xdp_frame **frames, u32 flags)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct receive_queue *rq = vi->rq;
+	struct bpf_prog *xdp_prog;
+	struct send_queue *sq;
+	unsigned int len;
+	int packets = 0;
+	int bytes = 0;
+	int nxmit = 0;
+	int kicks = 0;
+	void *ptr;
+	int ret;
+	int i;
+
+	/* Only allow ndo_xdp_xmit if XDP is loaded on dev, as this
+	 * indicate XDP resources have been successfully allocated.
+	 */
+	xdp_prog = rcu_access_pointer(rq->xdp_prog);
+	if (!xdp_prog)
+		return -ENXIO;
+
+	sq = virtnet_xdp_get_sq(vi);
+
+	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* Free up any pending old buffers before queueing new ones. */
+	while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) {
+		if (likely(is_xdp_frame(ptr))) {
+			struct xdp_frame *frame = ptr_to_xdp(ptr);
+
+			bytes += xdp_get_frame_len(frame);
+			xdp_return_frame(frame);
+		} else {
+			struct sk_buff *skb = ptr;
+
+			bytes += skb->len;
+			napi_consume_skb(skb, false);
+		}
+		packets++;
+	}
+
+	for (i = 0; i < n; i++) {
+		struct xdp_frame *xdpf = frames[i];
+
+		if (__virtnet_xdp_xmit_one(vi, sq, xdpf))
+			break;
+		nxmit++;
+	}
+	ret = nxmit;
+
+	if (!is_xdp_raw_buffer_queue(vi, sq - vi->sq))
+		check_sq_full_and_disable(vi, dev, sq);
+
+	if (flags & XDP_XMIT_FLUSH) {
+		if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
+			kicks = 1;
+	}
+out:
+	u64_stats_update_begin(&sq->stats.syncp);
+	u64_stats_add(&sq->stats.bytes, bytes);
+	u64_stats_add(&sq->stats.packets, packets);
+	u64_stats_add(&sq->stats.xdp_tx, n);
+	u64_stats_add(&sq->stats.xdp_tx_drops, n - nxmit);
+	u64_stats_add(&sq->stats.kicks, kicks);
+	u64_stats_update_end(&sq->stats.syncp);
+
+	virtnet_xdp_put_sq(vi, sq);
+	return ret;
+}
+
+static void put_xdp_frags(struct xdp_buff *xdp)
+{
+	struct skb_shared_info *shinfo;
+	struct page *xdp_page;
+	int i;
+
+	if (xdp_buff_has_frags(xdp)) {
+		shinfo = xdp_get_shared_info_from_buff(xdp);
+		for (i = 0; i < shinfo->nr_frags; i++) {
+			xdp_page = skb_frag_page(&shinfo->frags[i]);
+			put_page(xdp_page);
+		}
+	}
+}
+
+static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp,
+			       struct net_device *dev,
+			       unsigned int *xdp_xmit,
+			       struct virtnet_rq_stats *stats)
+{
+	struct xdp_frame *xdpf;
+	int err;
+	u32 act;
+
+	act = bpf_prog_run_xdp(xdp_prog, xdp);
+	u64_stats_inc(&stats->xdp_packets);
+
+	switch (act) {
+	case XDP_PASS:
+		return act;
+
+	case XDP_TX:
+		u64_stats_inc(&stats->xdp_tx);
+		xdpf = xdp_convert_buff_to_frame(xdp);
+		if (unlikely(!xdpf)) {
+			netdev_dbg(dev, "convert buff to frame failed for xdp\n");
+			return XDP_DROP;
+		}
+
+		err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
+		if (unlikely(!err)) {
+			xdp_return_frame_rx_napi(xdpf);
+		} else if (unlikely(err < 0)) {
+			trace_xdp_exception(dev, xdp_prog, act);
+			return XDP_DROP;
+		}
+		*xdp_xmit |= VIRTIO_XDP_TX;
+		return act;
+
+	case XDP_REDIRECT:
+		u64_stats_inc(&stats->xdp_redirects);
+		err = xdp_do_redirect(dev, xdp, xdp_prog);
+		if (err)
+			return XDP_DROP;
+
+		*xdp_xmit |= VIRTIO_XDP_REDIR;
+		return act;
+
+	default:
+		bpf_warn_invalid_xdp_action(dev, xdp_prog, act);
+		fallthrough;
+	case XDP_ABORTED:
+		trace_xdp_exception(dev, xdp_prog, act);
+		fallthrough;
+	case XDP_DROP:
+		return XDP_DROP;
+	}
+}
+
+static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
+{
+	return vi->xdp_enabled ? VIRTIO_XDP_HEADROOM : 0;
+}
+
+/* We copy the packet for XDP in the following cases:
+ *
+ * 1) Packet is scattered across multiple rx buffers.
+ * 2) Headroom space is insufficient.
+ *
+ * This is inefficient but it's a temporary condition that
+ * we hit right after XDP is enabled and until queue is refilled
+ * with large buffers with sufficient headroom - so it should affect
+ * at most queue size packets.
+ * Afterwards, the conditions to enable
+ * XDP should preclude the underlying device from sending packets
+ * across multiple buffers (num_buf > 1), and we make sure buffers
+ * have enough headroom.
+ */
+static struct page *xdp_linearize_page(struct receive_queue *rq,
+				       int *num_buf,
+				       struct page *p,
+				       int offset,
+				       int page_off,
+				       unsigned int *len)
+{
+	int tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+	struct page *page;
+
+	if (page_off + *len + tailroom > PAGE_SIZE)
+		return NULL;
+
+	page = alloc_page(GFP_ATOMIC);
+	if (!page)
+		return NULL;
+
+	memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
+	page_off += *len;
+
+	while (--*num_buf) {
+		unsigned int buflen;
+		void *buf;
+		int off;
+
+		buf = virtnet_rq_get_buf(rq, &buflen, NULL);
+		if (unlikely(!buf))
+			goto err_buf;
+
+		p = virt_to_head_page(buf);
+		off = buf - page_address(p);
+
+		/* guard against a misconfigured or uncooperative backend that
+		 * is sending packet larger than the MTU.
+		 */
+		if ((page_off + buflen + tailroom) > PAGE_SIZE) {
+			put_page(p);
+			goto err_buf;
+		}
+
+		memcpy(page_address(page) + page_off,
+		       page_address(p) + off, buflen);
+		page_off += buflen;
+		put_page(p);
+	}
+
+	/* Headroom does not contribute to packet length */
+	*len = page_off - VIRTIO_XDP_HEADROOM;
+	return page;
+err_buf:
+	__free_pages(page, 0);
+	return NULL;
+}
+
+static struct sk_buff *receive_small_build_skb(struct virtnet_info *vi,
+					       unsigned int xdp_headroom,
+					       void *buf,
+					       unsigned int len)
+{
+	unsigned int header_offset;
+	unsigned int headroom;
+	unsigned int buflen;
+	struct sk_buff *skb;
+
+	header_offset = VIRTNET_RX_PAD + xdp_headroom;
+	headroom = vi->hdr_len + header_offset;
+	buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
+		SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+
+	skb = virtnet_build_skb(buf, buflen, headroom, len);
+	if (unlikely(!skb))
+		return NULL;
+
+	buf += header_offset;
+	memcpy(skb_vnet_common_hdr(skb), buf, vi->hdr_len);
+
+	return skb;
+}
+
+static struct sk_buff *receive_small_xdp(struct net_device *dev,
+					 struct virtnet_info *vi,
+					 struct receive_queue *rq,
+					 struct bpf_prog *xdp_prog,
+					 void *buf,
+					 unsigned int xdp_headroom,
+					 unsigned int len,
+					 unsigned int *xdp_xmit,
+					 struct virtnet_rq_stats *stats)
+{
+	unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
+	unsigned int headroom = vi->hdr_len + header_offset;
+	struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
+	struct page *page = virt_to_head_page(buf);
+	struct page *xdp_page;
+	unsigned int buflen;
+	struct xdp_buff xdp;
+	struct sk_buff *skb;
+	unsigned int metasize = 0;
+	u32 act;
+
+	if (unlikely(hdr->hdr.gso_type))
+		goto err_xdp;
+
+	buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
+		SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+
+	if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
+		int offset = buf - page_address(page) + header_offset;
+		unsigned int tlen = len + vi->hdr_len;
+		int num_buf = 1;
+
+		xdp_headroom = virtnet_get_headroom(vi);
+		header_offset = VIRTNET_RX_PAD + xdp_headroom;
+		headroom = vi->hdr_len + header_offset;
+		buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
+			SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+		xdp_page = xdp_linearize_page(rq, &num_buf, page,
+					      offset, header_offset,
+					      &tlen);
+		if (!xdp_page)
+			goto err_xdp;
+
+		buf = page_address(xdp_page);
+		put_page(page);
+		page = xdp_page;
+	}
+
+	xdp_init_buff(&xdp, buflen, &rq->xdp_rxq);
+	xdp_prepare_buff(&xdp, buf + VIRTNET_RX_PAD + vi->hdr_len,
+			 xdp_headroom, len, true);
+
+	act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);
+
+	switch (act) {
+	case XDP_PASS:
+		/* Recalculate length in case bpf program changed it */
+		len = xdp.data_end - xdp.data;
+		metasize = xdp.data - xdp.data_meta;
+		break;
+
+	case XDP_TX:
+	case XDP_REDIRECT:
+		goto xdp_xmit;
+
+	default:
+		goto err_xdp;
+	}
+
+	skb = virtnet_build_skb(buf, buflen, xdp.data - buf, len);
+	if (unlikely(!skb))
+		goto err;
+
+	if (metasize)
+		skb_metadata_set(skb, metasize);
+
+	return skb;
+
+err_xdp:
+	u64_stats_inc(&stats->xdp_drops);
+err:
+	u64_stats_inc(&stats->drops);
+	put_page(page);
+xdp_xmit:
+	return NULL;
+}
+
+static struct sk_buff *receive_small(struct net_device *dev,
+				     struct virtnet_info *vi,
+				     struct receive_queue *rq,
+				     void *buf, void *ctx,
+				     unsigned int len,
+				     unsigned int *xdp_xmit,
+				     struct virtnet_rq_stats *stats)
+{
+	unsigned int xdp_headroom = (unsigned long)ctx;
+	struct page *page = virt_to_head_page(buf);
+	struct sk_buff *skb;
+
+	len -= vi->hdr_len;
+	u64_stats_add(&stats->bytes, len);
+
+	if (unlikely(len > GOOD_PACKET_LEN)) {
+		pr_debug("%s: rx error: len %u exceeds max size %d\n",
+			 dev->name, len, GOOD_PACKET_LEN);
+		DEV_STATS_INC(dev, rx_length_errors);
+		goto err;
+	}
+
+	if (unlikely(vi->xdp_enabled)) {
+		struct bpf_prog *xdp_prog;
+
+		rcu_read_lock();
+		xdp_prog = rcu_dereference(rq->xdp_prog);
+		if (xdp_prog) {
+			skb = receive_small_xdp(dev, vi, rq, xdp_prog, buf,
+						xdp_headroom, len, xdp_xmit,
+						stats);
+			rcu_read_unlock();
+			return skb;
+		}
+		rcu_read_unlock();
+	}
+
+	skb = receive_small_build_skb(vi, xdp_headroom, buf, len);
+	if (likely(skb))
+		return skb;
+
+err:
+	u64_stats_inc(&stats->drops);
+	put_page(page);
+	return NULL;
+}
+
+static struct sk_buff *receive_big(struct net_device *dev,
+				   struct virtnet_info *vi,
+				   struct receive_queue *rq,
+				   void *buf,
+				   unsigned int len,
+				   struct virtnet_rq_stats *stats)
+{
+	struct page *page = buf;
+	struct sk_buff *skb =
+		page_to_skb(vi, rq, page, 0, len, PAGE_SIZE, 0);
+
+	u64_stats_add(&stats->bytes, len - vi->hdr_len);
+	if (unlikely(!skb))
+		goto err;
+
+	return skb;
+
+err:
+	u64_stats_inc(&stats->drops);
+	give_pages(rq, page);
+	return NULL;
+}
+
+static void mergeable_buf_free(struct receive_queue *rq, int num_buf,
+			       struct net_device *dev,
+			       struct virtnet_rq_stats *stats)
+{
+	struct page *page;
+	void *buf;
+	int len;
+
+	while (num_buf-- > 1) {
+		buf = virtnet_rq_get_buf(rq, &len, NULL);
+		if (unlikely(!buf)) {
+			pr_debug("%s: rx error: %d buffers missing\n",
+				 dev->name, num_buf);
+			DEV_STATS_INC(dev, rx_length_errors);
+			break;
+		}
+		u64_stats_add(&stats->bytes, len);
+		page = virt_to_head_page(buf);
+		put_page(page);
+	}
+}
+
+/* Why not use xdp_build_skb_from_frame() ?
+ * XDP core assumes that xdp frags are PAGE_SIZE in length, while in
+ * virtio-net there are 2 points that do not match its requirements:
+ *  1. The size of the prefilled buffer is not fixed before xdp is set.
+ *  2. xdp_build_skb_from_frame() does more checks that we don't need,
+ *     like eth_type_trans() (which virtio-net does in receive_buf()).
+ */
+static struct sk_buff *build_skb_from_xdp_buff(struct net_device *dev,
+					       struct virtnet_info *vi,
+					       struct xdp_buff *xdp,
+					       unsigned int xdp_frags_truesz)
+{
+	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
+	unsigned int headroom, data_len;
+	struct sk_buff *skb;
+	int metasize;
+	u8 nr_frags;
+
+	if (unlikely(xdp->data_end > xdp_data_hard_end(xdp))) {
+		pr_debug("Error building skb as missing reserved tailroom for xdp");
+		return NULL;
+	}
+
+	if (unlikely(xdp_buff_has_frags(xdp)))
+		nr_frags = sinfo->nr_frags;
+
+	skb = build_skb(xdp->data_hard_start, xdp->frame_sz);
+	if (unlikely(!skb))
+		return NULL;
+
+	headroom = xdp->data - xdp->data_hard_start;
+	data_len = xdp->data_end - xdp->data;
+	skb_reserve(skb, headroom);
+	__skb_put(skb, data_len);
+
+	metasize = xdp->data - xdp->data_meta;
+	metasize = metasize > 0 ? metasize : 0;
+	if (metasize)
+		skb_metadata_set(skb, metasize);
+
+	if (unlikely(xdp_buff_has_frags(xdp)))
+		xdp_update_skb_shared_info(skb, nr_frags,
+					   sinfo->xdp_frags_size,
+					   xdp_frags_truesz,
+					   xdp_buff_is_frag_pfmemalloc(xdp));
+
+	return skb;
+}
+
+/* TODO: build xdp in big mode */
+static int virtnet_build_xdp_buff_mrg(struct net_device *dev,
+				      struct virtnet_info *vi,
+				      struct receive_queue *rq,
+				      struct xdp_buff *xdp,
+				      void *buf,
+				      unsigned int len,
+				      unsigned int frame_sz,
+				      int *num_buf,
+				      unsigned int *xdp_frags_truesize,
+				      struct virtnet_rq_stats *stats)
+{
+	struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
+	unsigned int headroom, tailroom, room;
+	unsigned int truesize, cur_frag_size;
+	struct skb_shared_info *shinfo;
+	unsigned int xdp_frags_truesz = 0;
+	struct page *page;
+	skb_frag_t *frag;
+	int offset;
+	void *ctx;
+
+	xdp_init_buff(xdp, frame_sz, &rq->xdp_rxq);
+	xdp_prepare_buff(xdp, buf - VIRTIO_XDP_HEADROOM,
+			 VIRTIO_XDP_HEADROOM + vi->hdr_len, len - vi->hdr_len, true);
+
+	if (!*num_buf)
+		return 0;
+
+	if (*num_buf > 1) {
+		/* If we want to build multi-buffer xdp, we need
+		 * to specify that the flags of xdp_buff have the
+		 * XDP_FLAGS_HAS_FRAG bit.
+		 */
+		if (!xdp_buff_has_frags(xdp))
+			xdp_buff_set_frags_flag(xdp);
+
+		shinfo = xdp_get_shared_info_from_buff(xdp);
+		shinfo->nr_frags = 0;
+		shinfo->xdp_frags_size = 0;
+	}
+
+	if (*num_buf > MAX_SKB_FRAGS + 1)
+		return -EINVAL;
+
+	while (--*num_buf > 0) {
+		buf = virtnet_rq_get_buf(rq, &len, &ctx);
+		if (unlikely(!buf)) {
+			pr_debug("%s: rx error: %d buffers out of %d missing\n",
+				 dev->name, *num_buf,
+				 virtio16_to_cpu(vi->vdev, hdr->num_buffers));
+			DEV_STATS_INC(dev, rx_length_errors);
+			goto err;
+		}
+
+		u64_stats_add(&stats->bytes, len);
+		page = virt_to_head_page(buf);
+		offset = buf - page_address(page);
+
+		truesize = mergeable_ctx_to_truesize(ctx);
+		headroom = mergeable_ctx_to_headroom(ctx);
+		tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
+		room = SKB_DATA_ALIGN(headroom + tailroom);
+
+		cur_frag_size = truesize;
+		xdp_frags_truesz += cur_frag_size;
+		if (unlikely(len > truesize - room || cur_frag_size > PAGE_SIZE)) {
+			put_page(page);
+			pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
+				 dev->name, len, (unsigned long)(truesize - room));
+			DEV_STATS_INC(dev, rx_length_errors);
+			goto err;
+		}
+
+		frag = &shinfo->frags[shinfo->nr_frags++];
+		skb_frag_fill_page_desc(frag, page, offset, len);
+		if (page_is_pfmemalloc(page))
+			xdp_buff_set_frag_pfmemalloc(xdp);
+
+		shinfo->xdp_frags_size += len;
+	}
+
+	*xdp_frags_truesize = xdp_frags_truesz;
+	return 0;
+
+err:
+	put_xdp_frags(xdp);
+	return -EINVAL;
+}
+
+static void *mergeable_xdp_get_buf(struct virtnet_info *vi,
+				   struct receive_queue *rq,
+				   struct bpf_prog *xdp_prog,
+				   void *ctx,
+				   unsigned int *frame_sz,
+				   int *num_buf,
+				   struct page **page,
+				   int offset,
+				   unsigned int *len,
+				   struct virtio_net_hdr_mrg_rxbuf *hdr)
+{
+	unsigned int truesize = mergeable_ctx_to_truesize(ctx);
+	unsigned int headroom = mergeable_ctx_to_headroom(ctx);
+	struct page *xdp_page;
+	unsigned int xdp_room;
+
+	/* Transient failure which in theory could occur if
+	 * in-flight packets from before XDP was enabled reach
+	 * the receive path after XDP is loaded.
+	 */
+	if (unlikely(hdr->hdr.gso_type))
+		return NULL;
+
+	/* Now XDP core assumes frag size is PAGE_SIZE, but buffers
+	 * with headroom may add hole in truesize, which
+	 * make their length exceed PAGE_SIZE. So we disabled the
+	 * hole mechanism for xdp. See add_recvbuf_mergeable().
+	 */
+	*frame_sz = truesize;
+
+	if (likely(headroom >= virtnet_get_headroom(vi) &&
+		   (*num_buf == 1 || xdp_prog->aux->xdp_has_frags))) {
+		return page_address(*page) + offset;
+	}
+
+	/* This happens when headroom is not enough because
+	 * of the buffer was prefilled before XDP is set.
+	 * This should only happen for the first several packets.
+	 * In fact, vq reset can be used here to help us clean up
+	 * the prefilled buffers, but many existing devices do not
+	 * support it, and we don't want to bother users who are
+	 * using xdp normally.
+	 */
+	if (!xdp_prog->aux->xdp_has_frags) {
+		/* linearize data for XDP */
+		xdp_page = xdp_linearize_page(rq, num_buf,
+					      *page, offset,
+					      VIRTIO_XDP_HEADROOM,
+					      len);
+		if (!xdp_page)
+			return NULL;
+	} else {
+		xdp_room = SKB_DATA_ALIGN(VIRTIO_XDP_HEADROOM +
+					  sizeof(struct skb_shared_info));
+		if (*len + xdp_room > PAGE_SIZE)
+			return NULL;
+
+		xdp_page = alloc_page(GFP_ATOMIC);
+		if (!xdp_page)
+			return NULL;
+
+		memcpy(page_address(xdp_page) + VIRTIO_XDP_HEADROOM,
+		       page_address(*page) + offset, *len);
+	}
+
+	*frame_sz = PAGE_SIZE;
+
+	put_page(*page);
+
+	*page = xdp_page;
+
+	return page_address(*page) + VIRTIO_XDP_HEADROOM;
+}
+
+static struct sk_buff *receive_mergeable_xdp(struct net_device *dev,
+					     struct virtnet_info *vi,
+					     struct receive_queue *rq,
+					     struct bpf_prog *xdp_prog,
+					     void *buf,
+					     void *ctx,
+					     unsigned int len,
+					     unsigned int *xdp_xmit,
+					     struct virtnet_rq_stats *stats)
+{
+	struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
+	int num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
+	struct page *page = virt_to_head_page(buf);
+	int offset = buf - page_address(page);
+	unsigned int xdp_frags_truesz = 0;
+	struct sk_buff *head_skb;
+	unsigned int frame_sz;
+	struct xdp_buff xdp;
+	void *data;
+	u32 act;
+	int err;
+
+	data = mergeable_xdp_get_buf(vi, rq, xdp_prog, ctx, &frame_sz, &num_buf, &page,
+				     offset, &len, hdr);
+	if (unlikely(!data))
+		goto err_xdp;
+
+	err = virtnet_build_xdp_buff_mrg(dev, vi, rq, &xdp, data, len, frame_sz,
+					 &num_buf, &xdp_frags_truesz, stats);
+	if (unlikely(err))
+		goto err_xdp;
+
+	act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);
+
+	switch (act) {
+	case XDP_PASS:
+		head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz);
+		if (unlikely(!head_skb))
+			break;
+		return head_skb;
+
+	case XDP_TX:
+	case XDP_REDIRECT:
+		return NULL;
+
+	default:
+		break;
+	}
+
+	put_xdp_frags(&xdp);
+
+err_xdp:
+	put_page(page);
+	mergeable_buf_free(rq, num_buf, dev, stats);
+
+	u64_stats_inc(&stats->xdp_drops);
+	u64_stats_inc(&stats->drops);
+	return NULL;
+}
+
+static struct sk_buff *receive_mergeable(struct net_device *dev,
+					 struct virtnet_info *vi,
+					 struct receive_queue *rq,
+					 void *buf,
+					 void *ctx,
+					 unsigned int len,
+					 unsigned int *xdp_xmit,
+					 struct virtnet_rq_stats *stats)
+{
+	struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
+	int num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
+	struct page *page = virt_to_head_page(buf);
+	int offset = buf - page_address(page);
+	struct sk_buff *head_skb, *curr_skb;
+	unsigned int truesize = mergeable_ctx_to_truesize(ctx);
+	unsigned int headroom = mergeable_ctx_to_headroom(ctx);
+	unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
+	unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
+
+	head_skb = NULL;
+	u64_stats_add(&stats->bytes, len - vi->hdr_len);
+
+	if (unlikely(len > truesize - room)) {
+		pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
+			 dev->name, len, (unsigned long)(truesize - room));
+		DEV_STATS_INC(dev, rx_length_errors);
+		goto err_skb;
+	}
+
+	if (unlikely(vi->xdp_enabled)) {
+		struct bpf_prog *xdp_prog;
+
+		rcu_read_lock();
+		xdp_prog = rcu_dereference(rq->xdp_prog);
+		if (xdp_prog) {
+			head_skb = receive_mergeable_xdp(dev, vi, rq, xdp_prog, buf, ctx,
+							 len, xdp_xmit, stats);
+			rcu_read_unlock();
+			return head_skb;
+		}
+		rcu_read_unlock();
+	}
+
+	head_skb = page_to_skb(vi, rq, page, offset, len, truesize, headroom);
+	curr_skb = head_skb;
+
+	if (unlikely(!curr_skb))
+		goto err_skb;
+	while (--num_buf) {
+		int num_skb_frags;
+
+		buf = virtnet_rq_get_buf(rq, &len, &ctx);
+		if (unlikely(!buf)) {
+			pr_debug("%s: rx error: %d buffers out of %d missing\n",
+				 dev->name, num_buf,
+				 virtio16_to_cpu(vi->vdev,
+						 hdr->num_buffers));
+			DEV_STATS_INC(dev, rx_length_errors);
+			goto err_buf;
+		}
+
+		u64_stats_add(&stats->bytes, len);
+		page = virt_to_head_page(buf);
+
+		truesize = mergeable_ctx_to_truesize(ctx);
+		headroom = mergeable_ctx_to_headroom(ctx);
+		tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
+		room = SKB_DATA_ALIGN(headroom + tailroom);
+		if (unlikely(len > truesize - room)) {
+			pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
+				 dev->name, len, (unsigned long)(truesize - room));
+			DEV_STATS_INC(dev, rx_length_errors);
+			goto err_skb;
+		}
+
+		num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
+		if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
+			struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
+
+			if (unlikely(!nskb))
+				goto err_skb;
+			if (curr_skb == head_skb)
+				skb_shinfo(curr_skb)->frag_list = nskb;
+			else
+				curr_skb->next = nskb;
+			curr_skb = nskb;
+			head_skb->truesize += nskb->truesize;
+			num_skb_frags = 0;
+		}
+		if (curr_skb != head_skb) {
+			head_skb->data_len += len;
+			head_skb->len += len;
+			head_skb->truesize += truesize;
+		}
+		offset = buf - page_address(page);
+		if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
+			put_page(page);
+			skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
+					     len, truesize);
+		} else {
+			skb_add_rx_frag(curr_skb, num_skb_frags, page,
+					offset, len, truesize);
+		}
+	}
+
+	ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
+	return head_skb;
+
+err_skb:
+	put_page(page);
+	mergeable_buf_free(rq, num_buf, dev, stats);
+
+err_buf:
+	u64_stats_inc(&stats->drops);
+	dev_kfree_skb(head_skb);
+	return NULL;
+}
+
+static void virtio_skb_set_hash(const struct virtio_net_hdr_v1_hash *hdr_hash,
+				struct sk_buff *skb)
+{
+	enum pkt_hash_types rss_hash_type;
+
+	if (!hdr_hash || !skb)
+		return;
+
+	switch (__le16_to_cpu(hdr_hash->hash_report)) {
+	case VIRTIO_NET_HASH_REPORT_TCPv4:
+	case VIRTIO_NET_HASH_REPORT_UDPv4:
+	case VIRTIO_NET_HASH_REPORT_TCPv6:
+	case VIRTIO_NET_HASH_REPORT_UDPv6:
+	case VIRTIO_NET_HASH_REPORT_TCPv6_EX:
+	case VIRTIO_NET_HASH_REPORT_UDPv6_EX:
+		rss_hash_type = PKT_HASH_TYPE_L4;
+		break;
+	case VIRTIO_NET_HASH_REPORT_IPv4:
+	case VIRTIO_NET_HASH_REPORT_IPv6:
+	case VIRTIO_NET_HASH_REPORT_IPv6_EX:
+		rss_hash_type = PKT_HASH_TYPE_L3;
+		break;
+	case VIRTIO_NET_HASH_REPORT_NONE:
+	default:
+		rss_hash_type = PKT_HASH_TYPE_NONE;
+	}
+	skb_set_hash(skb, __le32_to_cpu(hdr_hash->hash_value), rss_hash_type);
+}
+
+static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
+			void *buf, unsigned int len, void **ctx,
+			unsigned int *xdp_xmit,
+			struct virtnet_rq_stats *stats)
+{
+	struct net_device *dev = vi->dev;
+	struct sk_buff *skb;
+	struct virtio_net_common_hdr *hdr;
+
+	if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
+		pr_debug("%s: short packet %i\n", dev->name, len);
+		DEV_STATS_INC(dev, rx_length_errors);
+		virtnet_rq_free_buf(vi, rq, buf);
+		return;
+	}
+
+	if (vi->mergeable_rx_bufs)
+		skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit,
+					stats);
+	else if (vi->big_packets)
+		skb = receive_big(dev, vi, rq, buf, len, stats);
+	else
+		skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats);
+
+	if (unlikely(!skb))
+		return;
+
+	hdr = skb_vnet_common_hdr(skb);
+	if (dev->features & NETIF_F_RXHASH && vi->has_rss_hash_report)
+		virtio_skb_set_hash(&hdr->hash_v1_hdr, skb);
+
+	if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+	if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
+				  virtio_is_little_endian(vi->vdev))) {
+		net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
+				     dev->name, hdr->hdr.gso_type,
+				     hdr->hdr.gso_size);
+		goto frame_err;
+	}
+
+	skb_record_rx_queue(skb, vq2rxq(rq->vq));
+	skb->protocol = eth_type_trans(skb, dev);
+	pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
+		 ntohs(skb->protocol), skb->len, skb->pkt_type);
+
+	napi_gro_receive(&rq->napi, skb);
+	return;
+
+frame_err:
+	DEV_STATS_INC(dev, rx_frame_errors);
+	dev_kfree_skb(skb);
+}
+
+/* Unlike mergeable buffers, all buffers are allocated to the
+ * same size, except for the headroom. For this reason we do
+ * not need to use  mergeable_len_to_ctx here - it is enough
+ * to store the headroom as the context ignoring the truesize.
+ */
+static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
+			     gfp_t gfp)
+{
+	char *buf;
+	unsigned int xdp_headroom = virtnet_get_headroom(vi);
+	void *ctx = (void *)(unsigned long)xdp_headroom;
+	int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
+	int err;
+
+	len = SKB_DATA_ALIGN(len) +
+	      SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+
+	buf = virtnet_rq_alloc(rq, len, gfp);
+	if (unlikely(!buf))
+		return -ENOMEM;
+
+	virtnet_rq_init_one_sg(rq, buf + VIRTNET_RX_PAD + xdp_headroom,
+			       vi->hdr_len + GOOD_PACKET_LEN);
+
+	err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
+	if (err < 0) {
+		if (rq->do_dma)
+			virtnet_rq_unmap(rq, buf, 0);
+		put_page(virt_to_head_page(buf));
+	}
+
+	return err;
+}
+
+static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
+			   gfp_t gfp)
+{
+	struct page *first, *list = NULL;
+	char *p;
+	int i, err, offset;
+
+	sg_init_table(rq->sg, vi->big_packets_num_skbfrags + 2);
+
+	/* page in rq->sg[vi->big_packets_num_skbfrags + 1] is list tail */
+	for (i = vi->big_packets_num_skbfrags + 1; i > 1; --i) {
+		first = get_a_page(rq, gfp);
+		if (!first) {
+			if (list)
+				give_pages(rq, list);
+			return -ENOMEM;
+		}
+		sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
+
+		/* chain new page in list head to match sg */
+		first->private = (unsigned long)list;
+		list = first;
+	}
+
+	first = get_a_page(rq, gfp);
+	if (!first) {
+		give_pages(rq, list);
+		return -ENOMEM;
+	}
+	p = page_address(first);
+
+	/* rq->sg[0], rq->sg[1] share the same page */
+	/* a separated rq->sg[0] for header - required in case !any_header_sg */
+	sg_set_buf(&rq->sg[0], p, vi->hdr_len);
+
+	/* rq->sg[1] for data packet, from offset */
+	offset = sizeof(struct padded_vnet_hdr);
+	sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
+
+	/* chain first in list head */
+	first->private = (unsigned long)list;
+	err = virtqueue_add_inbuf(rq->vq, rq->sg, vi->big_packets_num_skbfrags + 2,
+				  first, gfp);
+	if (err < 0)
+		give_pages(rq, first);
+
+	return err;
+}
+
+static unsigned int get_mergeable_buf_len(struct receive_queue *rq,
+					  struct ewma_pkt_len *avg_pkt_len,
+					  unsigned int room)
+{
+	struct virtnet_info *vi = rq->vq->vdev->priv;
+	const size_t hdr_len = vi->hdr_len;
+	unsigned int len;
+
+	if (room)
+		return PAGE_SIZE - room;
+
+	len = hdr_len +	clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
+				rq->min_buf_len, PAGE_SIZE - hdr_len);
+
+	return ALIGN(len, L1_CACHE_BYTES);
+}
+
+static int add_recvbuf_mergeable(struct virtnet_info *vi,
+				 struct receive_queue *rq, gfp_t gfp)
+{
+	struct page_frag *alloc_frag = &rq->alloc_frag;
+	unsigned int headroom = virtnet_get_headroom(vi);
+	unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
+	unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
+	unsigned int len, hole;
+	void *ctx;
+	char *buf;
+	int err;
+
+	/* Extra tailroom is needed to satisfy XDP's assumption. This
+	 * means rx frags coalescing won't work, but consider we've
+	 * disabled GSO for XDP, it won't be a big issue.
+	 */
+	len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len, room);
+
+	buf = virtnet_rq_alloc(rq, len + room, gfp);
+	if (unlikely(!buf))
+		return -ENOMEM;
+
+	buf += headroom; /* advance address leaving hole at front of pkt */
+	hole = alloc_frag->size - alloc_frag->offset;
+	if (hole < len + room) {
+		/* To avoid internal fragmentation, if there is very likely not
+		 * enough space for another buffer, add the remaining space to
+		 * the current buffer.
+		 * XDP core assumes that frame_size of xdp_buff and the length
+		 * of the frag are PAGE_SIZE, so we disable the hole mechanism.
+		 */
+		if (!headroom)
+			len += hole;
+		alloc_frag->offset += hole;
+	}
+
+	virtnet_rq_init_one_sg(rq, buf, len);
+
+	ctx = mergeable_len_to_ctx(len + room, headroom);
+	err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp);
+	if (err < 0) {
+		if (rq->do_dma)
+			virtnet_rq_unmap(rq, buf, 0);
+		put_page(virt_to_head_page(buf));
+	}
+
+	return err;
+}
+
+/*
+ * Returns false if we couldn't fill entirely (OOM).
+ *
+ * Normally run in the receive path, but can also be run from ndo_open
+ * before we're receiving packets, or from refill_work which is
+ * careful to disable receiving (using napi_disable).
+ */
+static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
+			  gfp_t gfp)
+{
+	int err;
+	bool oom;
+
+	do {
+		if (vi->mergeable_rx_bufs)
+			err = add_recvbuf_mergeable(vi, rq, gfp);
+		else if (vi->big_packets)
+			err = add_recvbuf_big(vi, rq, gfp);
+		else
+			err = add_recvbuf_small(vi, rq, gfp);
+
+		oom = err == -ENOMEM;
+		if (err)
+			break;
+	} while (rq->vq->num_free);
+	if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
+		unsigned long flags;
+
+		flags = u64_stats_update_begin_irqsave(&rq->stats.syncp);
+		u64_stats_inc(&rq->stats.kicks);
+		u64_stats_update_end_irqrestore(&rq->stats.syncp, flags);
+	}
+
+	return !oom;
+}
+
+static void skb_recv_done(struct virtqueue *rvq)
+{
+	struct virtnet_info *vi = rvq->vdev->priv;
+	struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
+
+	virtqueue_napi_schedule(&rq->napi, rvq);
+}
+
+static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
+{
+	napi_enable(napi);
+
+	/* If all buffers were filled by other side before we napi_enabled, we
+	 * won't get another interrupt, so process any outstanding packets now.
+	 * Call local_bh_enable after to trigger softIRQ processing.
+	 */
+	local_bh_disable();
+	virtqueue_napi_schedule(napi, vq);
+	local_bh_enable();
+}
+
+static void virtnet_napi_tx_enable(struct virtnet_info *vi,
+				   struct virtqueue *vq,
+				   struct napi_struct *napi)
+{
+	if (!napi->weight)
+		return;
+
+	/* Tx napi touches cachelines on the cpu handling tx interrupts. Only
+	 * enable the feature if this is likely affine with the transmit path.
+	 */
+	if (!vi->affinity_hint_set) {
+		napi->weight = 0;
+		return;
+	}
+
+	return virtnet_napi_enable(vq, napi);
+}
+
+static void virtnet_napi_tx_disable(struct napi_struct *napi)
+{
+	if (napi->weight)
+		napi_disable(napi);
+}
+
+static void refill_work(struct work_struct *work)
+{
+	struct virtnet_info *vi =
+		container_of(work, struct virtnet_info, refill.work);
+	bool still_empty;
+	int i;
+
+	for (i = 0; i < vi->curr_queue_pairs; i++) {
+		struct receive_queue *rq = &vi->rq[i];
+
+		napi_disable(&rq->napi);
+		still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
+		virtnet_napi_enable(rq->vq, &rq->napi);
+
+		/* In theory, this can happen: if we don't get any buffers in
+		 * we will *never* try to fill again.
+		 */
+		if (still_empty)
+			schedule_delayed_work(&vi->refill, HZ/2);
+	}
+}
+
+static int virtnet_receive(struct receive_queue *rq, int budget,
+			   unsigned int *xdp_xmit)
+{
+	struct virtnet_info *vi = rq->vq->vdev->priv;
+	struct virtnet_rq_stats stats = {};
+	unsigned int len;
+	int packets = 0;
+	void *buf;
+	int i;
+
+	if (!vi->big_packets || vi->mergeable_rx_bufs) {
+		void *ctx;
+
+		while (packets < budget &&
+		       (buf = virtnet_rq_get_buf(rq, &len, &ctx))) {
+			receive_buf(vi, rq, buf, len, ctx, xdp_xmit, &stats);
+			packets++;
+		}
+	} else {
+		while (packets < budget &&
+		       (buf = virtnet_rq_get_buf(rq, &len, NULL)) != NULL) {
+			receive_buf(vi, rq, buf, len, NULL, xdp_xmit, &stats);
+			packets++;
+		}
+	}
+
+	if (rq->vq->num_free > min((unsigned int)budget, virtqueue_get_vring_size(rq->vq)) / 2) {
+		if (!try_fill_recv(vi, rq, GFP_ATOMIC)) {
+			spin_lock(&vi->refill_lock);
+			if (vi->refill_enabled)
+				schedule_delayed_work(&vi->refill, 0);
+			spin_unlock(&vi->refill_lock);
+		}
+	}
+
+	u64_stats_set(&stats.packets, packets);
+	u64_stats_update_begin(&rq->stats.syncp);
+	for (i = 0; i < VIRTNET_RQ_STATS_LEN; i++) {
+		size_t offset = virtnet_rq_stats_desc[i].offset;
+		u64_stats_t *item, *src;
+
+		item = (u64_stats_t *)((u8 *)&rq->stats + offset);
+		src = (u64_stats_t *)((u8 *)&stats + offset);
+		u64_stats_add(item, u64_stats_read(src));
+	}
+	u64_stats_update_end(&rq->stats.syncp);
+
+	return packets;
+}
+
+static void virtnet_poll_cleantx(struct receive_queue *rq)
+{
+	struct virtnet_info *vi = rq->vq->vdev->priv;
+	unsigned int index = vq2rxq(rq->vq);
+	struct send_queue *sq = &vi->sq[index];
+	struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index);
+
+	if (!sq->napi.weight || is_xdp_raw_buffer_queue(vi, index))
+		return;
+
+	if (__netif_tx_trylock(txq)) {
+		if (sq->reset) {
+			__netif_tx_unlock(txq);
+			return;
+		}
+
+		do {
+			virtqueue_disable_cb(sq->vq);
+			free_old_xmit_skbs(sq, true);
+		} while (unlikely(!virtqueue_enable_cb_delayed(sq->vq)));
+
+		if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
+			netif_tx_wake_queue(txq);
+
+		__netif_tx_unlock(txq);
+	}
+}
+
+static int virtnet_poll(struct napi_struct *napi, int budget)
+{
+	struct receive_queue *rq =
+		container_of(napi, struct receive_queue, napi);
+	struct virtnet_info *vi = rq->vq->vdev->priv;
+	struct send_queue *sq;
+	unsigned int received;
+	unsigned int xdp_xmit = 0;
+
+	virtnet_poll_cleantx(rq);
+
+	received = virtnet_receive(rq, budget, &xdp_xmit);
+
+	if (xdp_xmit & VIRTIO_XDP_REDIR)
+		xdp_do_flush();
+
+	/* Out of packets? */
+	if (received < budget)
+		virtqueue_napi_complete(napi, rq->vq, received);
+
+	if (xdp_xmit & VIRTIO_XDP_TX) {
+		sq = virtnet_xdp_get_sq(vi);
+		if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
+			u64_stats_update_begin(&sq->stats.syncp);
+			u64_stats_inc(&sq->stats.kicks);
+			u64_stats_update_end(&sq->stats.syncp);
+		}
+		virtnet_xdp_put_sq(vi, sq);
+	}
+
+	return received;
+}
+
+static void virtnet_disable_queue_pair(struct virtnet_info *vi, int qp_index)
+{
+	virtnet_napi_tx_disable(&vi->sq[qp_index].napi);
+	napi_disable(&vi->rq[qp_index].napi);
+	xdp_rxq_info_unreg(&vi->rq[qp_index].xdp_rxq);
+}
+
+static int virtnet_enable_queue_pair(struct virtnet_info *vi, int qp_index)
+{
+	struct net_device *dev = vi->dev;
+	int err;
+
+	err = xdp_rxq_info_reg(&vi->rq[qp_index].xdp_rxq, dev, qp_index,
+			       vi->rq[qp_index].napi.napi_id);
+	if (err < 0)
+		return err;
+
+	err = xdp_rxq_info_reg_mem_model(&vi->rq[qp_index].xdp_rxq,
+					 MEM_TYPE_PAGE_SHARED, NULL);
+	if (err < 0)
+		goto err_xdp_reg_mem_model;
+
+	virtnet_napi_enable(vi->rq[qp_index].vq, &vi->rq[qp_index].napi);
+	virtnet_napi_tx_enable(vi, vi->sq[qp_index].vq, &vi->sq[qp_index].napi);
+
+	return 0;
+
+err_xdp_reg_mem_model:
+	xdp_rxq_info_unreg(&vi->rq[qp_index].xdp_rxq);
+	return err;
+}
+
+static int virtnet_open(struct net_device *dev)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int i, err;
+
+	enable_delayed_refill(vi);
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		if (i < vi->curr_queue_pairs)
+			/* Make sure we have some buffers: if oom use wq. */
+			if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
+				schedule_delayed_work(&vi->refill, 0);
+
+		err = virtnet_enable_queue_pair(vi, i);
+		if (err < 0)
+			goto err_enable_qp;
+	}
+
+	return 0;
+
+err_enable_qp:
+	disable_delayed_refill(vi);
+	cancel_delayed_work_sync(&vi->refill);
+
+	for (i--; i >= 0; i--)
+		virtnet_disable_queue_pair(vi, i);
+	return err;
+}
+
+static int virtnet_poll_tx(struct napi_struct *napi, int budget)
+{
+	struct send_queue *sq = container_of(napi, struct send_queue, napi);
+	struct virtnet_info *vi = sq->vq->vdev->priv;
+	unsigned int index = vq2txq(sq->vq);
+	struct netdev_queue *txq;
+	int opaque;
+	bool done;
+
+	if (unlikely(is_xdp_raw_buffer_queue(vi, index))) {
+		/* We don't need to enable cb for XDP */
+		napi_complete_done(napi, 0);
+		return 0;
+	}
+
+	txq = netdev_get_tx_queue(vi->dev, index);
+	__netif_tx_lock(txq, raw_smp_processor_id());
+	virtqueue_disable_cb(sq->vq);
+	free_old_xmit_skbs(sq, true);
+
+	if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS)
+		netif_tx_wake_queue(txq);
+
+	opaque = virtqueue_enable_cb_prepare(sq->vq);
+
+	done = napi_complete_done(napi, 0);
+
+	if (!done)
+		virtqueue_disable_cb(sq->vq);
+
+	__netif_tx_unlock(txq);
+
+	if (done) {
+		if (unlikely(virtqueue_poll(sq->vq, opaque))) {
+			if (napi_schedule_prep(napi)) {
+				__netif_tx_lock(txq, raw_smp_processor_id());
+				virtqueue_disable_cb(sq->vq);
+				__netif_tx_unlock(txq);
+				__napi_schedule(napi);
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
+{
+	struct virtio_net_hdr_mrg_rxbuf *hdr;
+	const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
+	struct virtnet_info *vi = sq->vq->vdev->priv;
+	int num_sg;
+	unsigned hdr_len = vi->hdr_len;
+	bool can_push;
+
+	pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
+
+	can_push = vi->any_header_sg &&
+		!((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
+		!skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
+	/* Even if we can, don't push here yet as this would skew
+	 * csum_start offset below. */
+	if (can_push)
+		hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
+	else
+		hdr = &skb_vnet_common_hdr(skb)->mrg_hdr;
+
+	if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
+				    virtio_is_little_endian(vi->vdev), false,
+				    0))
+		return -EPROTO;
+
+	if (vi->mergeable_rx_bufs)
+		hdr->num_buffers = 0;
+
+	sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
+	if (can_push) {
+		__skb_push(skb, hdr_len);
+		num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
+		if (unlikely(num_sg < 0))
+			return num_sg;
+		/* Pull header back to avoid skew in tx bytes calculations. */
+		__skb_pull(skb, hdr_len);
+	} else {
+		sg_set_buf(sq->sg, hdr, hdr_len);
+		num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len);
+		if (unlikely(num_sg < 0))
+			return num_sg;
+		num_sg++;
+	}
+	return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
+}
+
+static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int qnum = skb_get_queue_mapping(skb);
+	struct send_queue *sq = &vi->sq[qnum];
+	int err;
+	struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
+	bool kick = !netdev_xmit_more();
+	bool use_napi = sq->napi.weight;
+
+	/* Free up any pending old buffers before queueing new ones. */
+	do {
+		if (use_napi)
+			virtqueue_disable_cb(sq->vq);
+
+		free_old_xmit_skbs(sq, false);
+
+	} while (use_napi && kick &&
+	       unlikely(!virtqueue_enable_cb_delayed(sq->vq)));
+
+	/* timestamp packet in software */
+	skb_tx_timestamp(skb);
+
+	/* Try to transmit */
+	err = xmit_skb(sq, skb);
+
+	/* This should not happen! */
+	if (unlikely(err)) {
+		DEV_STATS_INC(dev, tx_fifo_errors);
+		if (net_ratelimit())
+			dev_warn(&dev->dev,
+				 "Unexpected TXQ (%d) queue failure: %d\n",
+				 qnum, err);
+		DEV_STATS_INC(dev, tx_dropped);
+		dev_kfree_skb_any(skb);
+		return NETDEV_TX_OK;
+	}
+
+	/* Don't wait up for transmitted skbs to be freed. */
+	if (!use_napi) {
+		skb_orphan(skb);
+		nf_reset_ct(skb);
+	}
+
+	check_sq_full_and_disable(vi, dev, sq);
+
+	if (kick || netif_xmit_stopped(txq)) {
+		if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
+			u64_stats_update_begin(&sq->stats.syncp);
+			u64_stats_inc(&sq->stats.kicks);
+			u64_stats_update_end(&sq->stats.syncp);
+		}
+	}
+
+	return NETDEV_TX_OK;
+}
+
+static int virtnet_rx_resize(struct virtnet_info *vi,
+			     struct receive_queue *rq, u32 ring_num)
+{
+	bool running = netif_running(vi->dev);
+	int err, qindex;
+
+	qindex = rq - vi->rq;
+
+	if (running)
+		napi_disable(&rq->napi);
+
+	err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_unmap_free_buf);
+	if (err)
+		netdev_err(vi->dev, "resize rx fail: rx queue index: %d err: %d\n", qindex, err);
+
+	if (!try_fill_recv(vi, rq, GFP_KERNEL))
+		schedule_delayed_work(&vi->refill, 0);
+
+	if (running)
+		virtnet_napi_enable(rq->vq, &rq->napi);
+	return err;
+}
+
+static int virtnet_tx_resize(struct virtnet_info *vi,
+			     struct send_queue *sq, u32 ring_num)
+{
+	bool running = netif_running(vi->dev);
+	struct netdev_queue *txq;
+	int err, qindex;
+
+	qindex = sq - vi->sq;
+
+	if (running)
+		virtnet_napi_tx_disable(&sq->napi);
+
+	txq = netdev_get_tx_queue(vi->dev, qindex);
+
+	/* 1. wait all ximt complete
+	 * 2. fix the race of netif_stop_subqueue() vs netif_start_subqueue()
+	 */
+	__netif_tx_lock_bh(txq);
+
+	/* Prevent rx poll from accessing sq. */
+	sq->reset = true;
+
+	/* Prevent the upper layer from trying to send packets. */
+	netif_stop_subqueue(vi->dev, qindex);
+
+	__netif_tx_unlock_bh(txq);
+
+	err = virtqueue_resize(sq->vq, ring_num, virtnet_sq_free_unused_buf);
+	if (err)
+		netdev_err(vi->dev, "resize tx fail: tx queue index: %d err: %d\n", qindex, err);
+
+	__netif_tx_lock_bh(txq);
+	sq->reset = false;
+	netif_tx_wake_queue(txq);
+	__netif_tx_unlock_bh(txq);
+
+	if (running)
+		virtnet_napi_tx_enable(vi, sq->vq, &sq->napi);
+	return err;
+}
+
+/*
+ * Send command via the control virtqueue and check status.  Commands
+ * supported by the hypervisor, as indicated by feature bits, should
+ * never fail unless improperly formatted.
+ */
+static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
+				 struct scatterlist *out)
+{
+	struct scatterlist *sgs[4], hdr, stat;
+	unsigned out_num = 0, tmp;
+	int ret;
+
+	/* Caller should know better */
+	BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
+
+	vi->ctrl->status = ~0;
+	vi->ctrl->hdr.class = class;
+	vi->ctrl->hdr.cmd = cmd;
+	/* Add header */
+	sg_init_one(&hdr, &vi->ctrl->hdr, sizeof(vi->ctrl->hdr));
+	sgs[out_num++] = &hdr;
+
+	if (out)
+		sgs[out_num++] = out;
+
+	/* Add return status. */
+	sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status));
+	sgs[out_num] = &stat;
+
+	BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
+	ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
+	if (ret < 0) {
+		dev_warn(&vi->vdev->dev,
+			 "Failed to add sgs for command vq: %d\n.", ret);
+		return false;
+	}
+
+	if (unlikely(!virtqueue_kick(vi->cvq)))
+		return vi->ctrl->status == VIRTIO_NET_OK;
+
+	/* Spin for a response, the kick causes an ioport write, trapping
+	 * into the hypervisor, so the request should be handled immediately.
+	 */
+	while (!virtqueue_get_buf(vi->cvq, &tmp) &&
+	       !virtqueue_is_broken(vi->cvq))
+		cpu_relax();
+
+	return vi->ctrl->status == VIRTIO_NET_OK;
+}
+
+static int virtnet_set_mac_address(struct net_device *dev, void *p)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct virtio_device *vdev = vi->vdev;
+	int ret;
+	struct sockaddr *addr;
+	struct scatterlist sg;
+
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
+		return -EOPNOTSUPP;
+
+	addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
+	if (!addr)
+		return -ENOMEM;
+
+	ret = eth_prepare_mac_addr_change(dev, addr);
+	if (ret)
+		goto out;
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
+		sg_init_one(&sg, addr->sa_data, dev->addr_len);
+		if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
+					  VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
+			dev_warn(&vdev->dev,
+				 "Failed to set mac address by vq command.\n");
+			ret = -EINVAL;
+			goto out;
+		}
+	} else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
+		   !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
+		unsigned int i;
+
+		/* Naturally, this has an atomicity problem. */
+		for (i = 0; i < dev->addr_len; i++)
+			virtio_cwrite8(vdev,
+				       offsetof(struct virtio_net_config, mac) +
+				       i, addr->sa_data[i]);
+	}
+
+	eth_commit_mac_addr_change(dev, p);
+	ret = 0;
+
+out:
+	kfree(addr);
+	return ret;
+}
+
+static void virtnet_stats(struct net_device *dev,
+			  struct rtnl_link_stats64 *tot)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	unsigned int start;
+	int i;
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		u64 tpackets, tbytes, terrors, rpackets, rbytes, rdrops;
+		struct receive_queue *rq = &vi->rq[i];
+		struct send_queue *sq = &vi->sq[i];
+
+		do {
+			start = u64_stats_fetch_begin(&sq->stats.syncp);
+			tpackets = u64_stats_read(&sq->stats.packets);
+			tbytes   = u64_stats_read(&sq->stats.bytes);
+			terrors  = u64_stats_read(&sq->stats.tx_timeouts);
+		} while (u64_stats_fetch_retry(&sq->stats.syncp, start));
+
+		do {
+			start = u64_stats_fetch_begin(&rq->stats.syncp);
+			rpackets = u64_stats_read(&rq->stats.packets);
+			rbytes   = u64_stats_read(&rq->stats.bytes);
+			rdrops   = u64_stats_read(&rq->stats.drops);
+		} while (u64_stats_fetch_retry(&rq->stats.syncp, start));
+
+		tot->rx_packets += rpackets;
+		tot->tx_packets += tpackets;
+		tot->rx_bytes   += rbytes;
+		tot->tx_bytes   += tbytes;
+		tot->rx_dropped += rdrops;
+		tot->tx_errors  += terrors;
+	}
+
+	tot->tx_dropped = DEV_STATS_READ(dev, tx_dropped);
+	tot->tx_fifo_errors = DEV_STATS_READ(dev, tx_fifo_errors);
+	tot->rx_length_errors = DEV_STATS_READ(dev, rx_length_errors);
+	tot->rx_frame_errors = DEV_STATS_READ(dev, rx_frame_errors);
+}
+
+static void virtnet_ack_link_announce(struct virtnet_info *vi)
+{
+	rtnl_lock();
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
+				  VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
+		dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
+	rtnl_unlock();
+}
+
+static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
+{
+	struct scatterlist sg;
+	struct net_device *dev = vi->dev;
+
+	if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
+		return 0;
+
+	vi->ctrl->mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
+	sg_init_one(&sg, &vi->ctrl->mq, sizeof(vi->ctrl->mq));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
+				  VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
+		dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
+			 queue_pairs);
+		return -EINVAL;
+	} else {
+		vi->curr_queue_pairs = queue_pairs;
+		/* virtnet_open() will refill when device is going to up. */
+		if (dev->flags & IFF_UP)
+			schedule_delayed_work(&vi->refill, 0);
+	}
+
+	return 0;
+}
+
+static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
+{
+	int err;
+
+	rtnl_lock();
+	err = _virtnet_set_queues(vi, queue_pairs);
+	rtnl_unlock();
+	return err;
+}
+
+static int virtnet_close(struct net_device *dev)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int i;
+
+	/* Make sure NAPI doesn't schedule refill work */
+	disable_delayed_refill(vi);
+	/* Make sure refill_work doesn't re-enable napi! */
+	cancel_delayed_work_sync(&vi->refill);
+
+	for (i = 0; i < vi->max_queue_pairs; i++)
+		virtnet_disable_queue_pair(vi, i);
+
+	return 0;
+}
+
+static void virtnet_set_rx_mode(struct net_device *dev)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct scatterlist sg[2];
+	struct virtio_net_ctrl_mac *mac_data;
+	struct netdev_hw_addr *ha;
+	int uc_count;
+	int mc_count;
+	void *buf;
+	int i;
+
+	/* We can't dynamically set ndo_set_rx_mode, so return gracefully */
+	if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
+		return;
+
+	vi->ctrl->promisc = ((dev->flags & IFF_PROMISC) != 0);
+	vi->ctrl->allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
+
+	sg_init_one(sg, &vi->ctrl->promisc, sizeof(vi->ctrl->promisc));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
+				  VIRTIO_NET_CTRL_RX_PROMISC, sg))
+		dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
+			 vi->ctrl->promisc ? "en" : "dis");
+
+	sg_init_one(sg, &vi->ctrl->allmulti, sizeof(vi->ctrl->allmulti));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
+				  VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
+		dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
+			 vi->ctrl->allmulti ? "en" : "dis");
+
+	uc_count = netdev_uc_count(dev);
+	mc_count = netdev_mc_count(dev);
+	/* MAC filter - use one buffer for both lists */
+	buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
+		      (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
+	mac_data = buf;
+	if (!buf)
+		return;
+
+	sg_init_table(sg, 2);
+
+	/* Store the unicast list and count in the front of the buffer */
+	mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
+	i = 0;
+	netdev_for_each_uc_addr(ha, dev)
+		memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
+
+	sg_set_buf(&sg[0], mac_data,
+		   sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
+
+	/* multicast list and count fill the end */
+	mac_data = (void *)&mac_data->macs[uc_count][0];
+
+	mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
+	i = 0;
+	netdev_for_each_mc_addr(ha, dev)
+		memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
+
+	sg_set_buf(&sg[1], mac_data,
+		   sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
+				  VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
+		dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
+
+	kfree(buf);
+}
+
+static int virtnet_vlan_rx_add_vid(struct net_device *dev,
+				   __be16 proto, u16 vid)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct scatterlist sg;
+
+	vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
+	sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
+				  VIRTIO_NET_CTRL_VLAN_ADD, &sg))
+		dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
+	return 0;
+}
+
+static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
+				    __be16 proto, u16 vid)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct scatterlist sg;
+
+	vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid);
+	sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
+				  VIRTIO_NET_CTRL_VLAN_DEL, &sg))
+		dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
+	return 0;
+}
+
+static void virtnet_clean_affinity(struct virtnet_info *vi)
+{
+	int i;
+
+	if (vi->affinity_hint_set) {
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			virtqueue_set_affinity(vi->rq[i].vq, NULL);
+			virtqueue_set_affinity(vi->sq[i].vq, NULL);
+		}
+
+		vi->affinity_hint_set = false;
+	}
+}
+
+static void virtnet_set_affinity(struct virtnet_info *vi)
+{
+	cpumask_var_t mask;
+	int stragglers;
+	int group_size;
+	int i, j, cpu;
+	int num_cpu;
+	int stride;
+
+	if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) {
+		virtnet_clean_affinity(vi);
+		return;
+	}
+
+	num_cpu = num_online_cpus();
+	stride = max_t(int, num_cpu / vi->curr_queue_pairs, 1);
+	stragglers = num_cpu >= vi->curr_queue_pairs ?
+			num_cpu % vi->curr_queue_pairs :
+			0;
+	cpu = cpumask_first(cpu_online_mask);
+
+	for (i = 0; i < vi->curr_queue_pairs; i++) {
+		group_size = stride + (i < stragglers ? 1 : 0);
+
+		for (j = 0; j < group_size; j++) {
+			cpumask_set_cpu(cpu, mask);
+			cpu = cpumask_next_wrap(cpu, cpu_online_mask,
+						nr_cpu_ids, false);
+		}
+		virtqueue_set_affinity(vi->rq[i].vq, mask);
+		virtqueue_set_affinity(vi->sq[i].vq, mask);
+		__netif_set_xps_queue(vi->dev, cpumask_bits(mask), i, XPS_CPUS);
+		cpumask_clear(mask);
+	}
+
+	vi->affinity_hint_set = true;
+	free_cpumask_var(mask);
+}
+
+static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
+{
+	struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
+						   node);
+	virtnet_set_affinity(vi);
+	return 0;
+}
+
+static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
+{
+	struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
+						   node_dead);
+	virtnet_set_affinity(vi);
+	return 0;
+}
+
+static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
+{
+	struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
+						   node);
+
+	virtnet_clean_affinity(vi);
+	return 0;
+}
+
+static enum cpuhp_state virtionet_online;
+
+static int virtnet_cpu_notif_add(struct virtnet_info *vi)
+{
+	int ret;
+
+	ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
+	if (ret)
+		return ret;
+	ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
+					       &vi->node_dead);
+	if (!ret)
+		return ret;
+	cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
+	return ret;
+}
+
+static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
+{
+	cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
+	cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
+					    &vi->node_dead);
+}
+
+static void virtnet_get_ringparam(struct net_device *dev,
+				  struct ethtool_ringparam *ring,
+				  struct kernel_ethtool_ringparam *kernel_ring,
+				  struct netlink_ext_ack *extack)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	ring->rx_max_pending = vi->rq[0].vq->num_max;
+	ring->tx_max_pending = vi->sq[0].vq->num_max;
+	ring->rx_pending = virtqueue_get_vring_size(vi->rq[0].vq);
+	ring->tx_pending = virtqueue_get_vring_size(vi->sq[0].vq);
+}
+
+static int virtnet_send_ctrl_coal_vq_cmd(struct virtnet_info *vi,
+					 u16 vqn, u32 max_usecs, u32 max_packets);
+
+static int virtnet_set_ringparam(struct net_device *dev,
+				 struct ethtool_ringparam *ring,
+				 struct kernel_ethtool_ringparam *kernel_ring,
+				 struct netlink_ext_ack *extack)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	u32 rx_pending, tx_pending;
+	struct receive_queue *rq;
+	struct send_queue *sq;
+	int i, err;
+
+	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
+		return -EINVAL;
+
+	rx_pending = virtqueue_get_vring_size(vi->rq[0].vq);
+	tx_pending = virtqueue_get_vring_size(vi->sq[0].vq);
+
+	if (ring->rx_pending == rx_pending &&
+	    ring->tx_pending == tx_pending)
+		return 0;
+
+	if (ring->rx_pending > vi->rq[0].vq->num_max)
+		return -EINVAL;
+
+	if (ring->tx_pending > vi->sq[0].vq->num_max)
+		return -EINVAL;
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		rq = vi->rq + i;
+		sq = vi->sq + i;
+
+		if (ring->tx_pending != tx_pending) {
+			err = virtnet_tx_resize(vi, sq, ring->tx_pending);
+			if (err)
+				return err;
+
+			/* Upon disabling and re-enabling a transmit virtqueue, the device must
+			 * set the coalescing parameters of the virtqueue to those configured
+			 * through the VIRTIO_NET_CTRL_NOTF_COAL_TX_SET command, or, if the driver
+			 * did not set any TX coalescing parameters, to 0.
+			 */
+			err = virtnet_send_ctrl_coal_vq_cmd(vi, txq2vq(i),
+							    vi->intr_coal_tx.max_usecs,
+							    vi->intr_coal_tx.max_packets);
+			if (err)
+				return err;
+
+			vi->sq[i].intr_coal.max_usecs = vi->intr_coal_tx.max_usecs;
+			vi->sq[i].intr_coal.max_packets = vi->intr_coal_tx.max_packets;
+		}
+
+		if (ring->rx_pending != rx_pending) {
+			err = virtnet_rx_resize(vi, rq, ring->rx_pending);
+			if (err)
+				return err;
+
+			/* The reason is same as the transmit virtqueue reset */
+			err = virtnet_send_ctrl_coal_vq_cmd(vi, rxq2vq(i),
+							    vi->intr_coal_rx.max_usecs,
+							    vi->intr_coal_rx.max_packets);
+			if (err)
+				return err;
+
+			vi->rq[i].intr_coal.max_usecs = vi->intr_coal_rx.max_usecs;
+			vi->rq[i].intr_coal.max_packets = vi->intr_coal_rx.max_packets;
+		}
+	}
+
+	return 0;
+}
+
+static bool virtnet_commit_rss_command(struct virtnet_info *vi)
+{
+	struct net_device *dev = vi->dev;
+	struct scatterlist sgs[4];
+	unsigned int sg_buf_size;
+
+	/* prepare sgs */
+	sg_init_table(sgs, 4);
+
+	sg_buf_size = offsetof(struct virtio_net_ctrl_rss, indirection_table);
+	sg_set_buf(&sgs[0], &vi->ctrl->rss, sg_buf_size);
+
+	sg_buf_size = sizeof(uint16_t) * (vi->ctrl->rss.indirection_table_mask + 1);
+	sg_set_buf(&sgs[1], vi->ctrl->rss.indirection_table, sg_buf_size);
+
+	sg_buf_size = offsetof(struct virtio_net_ctrl_rss, key)
+			- offsetof(struct virtio_net_ctrl_rss, max_tx_vq);
+	sg_set_buf(&sgs[2], &vi->ctrl->rss.max_tx_vq, sg_buf_size);
+
+	sg_buf_size = vi->rss_key_size;
+	sg_set_buf(&sgs[3], vi->ctrl->rss.key, sg_buf_size);
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
+				  vi->has_rss ? VIRTIO_NET_CTRL_MQ_RSS_CONFIG
+				  : VIRTIO_NET_CTRL_MQ_HASH_CONFIG, sgs)) {
+		dev_warn(&dev->dev, "VIRTIONET issue with committing RSS sgs\n");
+		return false;
+	}
+	return true;
+}
+
+static void virtnet_init_default_rss(struct virtnet_info *vi)
+{
+	u32 indir_val = 0;
+	int i = 0;
+
+	vi->ctrl->rss.hash_types = vi->rss_hash_types_supported;
+	vi->rss_hash_types_saved = vi->rss_hash_types_supported;
+	vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size
+						? vi->rss_indir_table_size - 1 : 0;
+	vi->ctrl->rss.unclassified_queue = 0;
+
+	for (; i < vi->rss_indir_table_size; ++i) {
+		indir_val = ethtool_rxfh_indir_default(i, vi->curr_queue_pairs);
+		vi->ctrl->rss.indirection_table[i] = indir_val;
+	}
+
+	vi->ctrl->rss.max_tx_vq = vi->has_rss ? vi->curr_queue_pairs : 0;
+	vi->ctrl->rss.hash_key_length = vi->rss_key_size;
+
+	netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size);
+}
+
+static void virtnet_get_hashflow(const struct virtnet_info *vi, struct ethtool_rxnfc *info)
+{
+	info->data = 0;
+	switch (info->flow_type) {
+	case TCP_V4_FLOW:
+		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) {
+			info->data = RXH_IP_SRC | RXH_IP_DST |
+						 RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		} else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
+			info->data = RXH_IP_SRC | RXH_IP_DST;
+		}
+		break;
+	case TCP_V6_FLOW:
+		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) {
+			info->data = RXH_IP_SRC | RXH_IP_DST |
+						 RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		} else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
+			info->data = RXH_IP_SRC | RXH_IP_DST;
+		}
+		break;
+	case UDP_V4_FLOW:
+		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) {
+			info->data = RXH_IP_SRC | RXH_IP_DST |
+						 RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		} else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
+			info->data = RXH_IP_SRC | RXH_IP_DST;
+		}
+		break;
+	case UDP_V6_FLOW:
+		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) {
+			info->data = RXH_IP_SRC | RXH_IP_DST |
+						 RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		} else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
+			info->data = RXH_IP_SRC | RXH_IP_DST;
+		}
+		break;
+	case IPV4_FLOW:
+		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4)
+			info->data = RXH_IP_SRC | RXH_IP_DST;
+
+		break;
+	case IPV6_FLOW:
+		if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6)
+			info->data = RXH_IP_SRC | RXH_IP_DST;
+
+		break;
+	default:
+		info->data = 0;
+		break;
+	}
+}
+
+static bool virtnet_set_hashflow(struct virtnet_info *vi, struct ethtool_rxnfc *info)
+{
+	u32 new_hashtypes = vi->rss_hash_types_saved;
+	bool is_disable = info->data & RXH_DISCARD;
+	bool is_l4 = info->data == (RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3);
+
+	/* supports only 'sd', 'sdfn' and 'r' */
+	if (!((info->data == (RXH_IP_SRC | RXH_IP_DST)) | is_l4 | is_disable))
+		return false;
+
+	switch (info->flow_type) {
+	case TCP_V4_FLOW:
+		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_TCPv4);
+		if (!is_disable)
+			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
+				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv4 : 0);
+		break;
+	case UDP_V4_FLOW:
+		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_UDPv4);
+		if (!is_disable)
+			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4
+				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv4 : 0);
+		break;
+	case IPV4_FLOW:
+		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4;
+		if (!is_disable)
+			new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv4;
+		break;
+	case TCP_V6_FLOW:
+		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_TCPv6);
+		if (!is_disable)
+			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
+				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv6 : 0);
+		break;
+	case UDP_V6_FLOW:
+		new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_UDPv6);
+		if (!is_disable)
+			new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6
+				| (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv6 : 0);
+		break;
+	case IPV6_FLOW:
+		new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6;
+		if (!is_disable)
+			new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv6;
+		break;
+	default:
+		/* unsupported flow */
+		return false;
+	}
+
+	/* if unsupported hashtype was set */
+	if (new_hashtypes != (new_hashtypes & vi->rss_hash_types_supported))
+		return false;
+
+	if (new_hashtypes != vi->rss_hash_types_saved) {
+		vi->rss_hash_types_saved = new_hashtypes;
+		vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
+		if (vi->dev->features & NETIF_F_RXHASH)
+			return virtnet_commit_rss_command(vi);
+	}
+
+	return true;
+}
+
+static void virtnet_get_drvinfo(struct net_device *dev,
+				struct ethtool_drvinfo *info)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct virtio_device *vdev = vi->vdev;
+
+	strscpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
+	strscpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
+	strscpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
+
+}
+
+/* TODO: Eliminate OOO packets during switching */
+static int virtnet_set_channels(struct net_device *dev,
+				struct ethtool_channels *channels)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	u16 queue_pairs = channels->combined_count;
+	int err;
+
+	/* We don't support separate rx/tx channels.
+	 * We don't allow setting 'other' channels.
+	 */
+	if (channels->rx_count || channels->tx_count || channels->other_count)
+		return -EINVAL;
+
+	if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
+		return -EINVAL;
+
+	/* For now we don't support modifying channels while XDP is loaded
+	 * also when XDP is loaded all RX queues have XDP programs so we only
+	 * need to check a single RX queue.
+	 */
+	if (vi->rq[0].xdp_prog)
+		return -EINVAL;
+
+	cpus_read_lock();
+	err = _virtnet_set_queues(vi, queue_pairs);
+	if (err) {
+		cpus_read_unlock();
+		goto err;
+	}
+	virtnet_set_affinity(vi);
+	cpus_read_unlock();
+
+	netif_set_real_num_tx_queues(dev, queue_pairs);
+	netif_set_real_num_rx_queues(dev, queue_pairs);
+ err:
+	return err;
+}
+
+static void virtnet_get_strings(struct net_device *dev, u32 stringset, u8 *data)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	unsigned int i, j;
+	u8 *p = data;
+
+	switch (stringset) {
+	case ETH_SS_STATS:
+		for (i = 0; i < vi->curr_queue_pairs; i++) {
+			for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++)
+				ethtool_sprintf(&p, "rx_queue_%u_%s", i,
+						virtnet_rq_stats_desc[j].desc);
+		}
+
+		for (i = 0; i < vi->curr_queue_pairs; i++) {
+			for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++)
+				ethtool_sprintf(&p, "tx_queue_%u_%s", i,
+						virtnet_sq_stats_desc[j].desc);
+		}
+		break;
+	}
+}
+
+static int virtnet_get_sset_count(struct net_device *dev, int sset)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	switch (sset) {
+	case ETH_SS_STATS:
+		return vi->curr_queue_pairs * (VIRTNET_RQ_STATS_LEN +
+					       VIRTNET_SQ_STATS_LEN);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static void virtnet_get_ethtool_stats(struct net_device *dev,
+				      struct ethtool_stats *stats, u64 *data)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	unsigned int idx = 0, start, i, j;
+	const u8 *stats_base;
+	const u64_stats_t *p;
+	size_t offset;
+
+	for (i = 0; i < vi->curr_queue_pairs; i++) {
+		struct receive_queue *rq = &vi->rq[i];
+
+		stats_base = (const u8 *)&rq->stats;
+		do {
+			start = u64_stats_fetch_begin(&rq->stats.syncp);
+			for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) {
+				offset = virtnet_rq_stats_desc[j].offset;
+				p = (const u64_stats_t *)(stats_base + offset);
+				data[idx + j] = u64_stats_read(p);
+			}
+		} while (u64_stats_fetch_retry(&rq->stats.syncp, start));
+		idx += VIRTNET_RQ_STATS_LEN;
+	}
+
+	for (i = 0; i < vi->curr_queue_pairs; i++) {
+		struct send_queue *sq = &vi->sq[i];
+
+		stats_base = (const u8 *)&sq->stats;
+		do {
+			start = u64_stats_fetch_begin(&sq->stats.syncp);
+			for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) {
+				offset = virtnet_sq_stats_desc[j].offset;
+				p = (const u64_stats_t *)(stats_base + offset);
+				data[idx + j] = u64_stats_read(p);
+			}
+		} while (u64_stats_fetch_retry(&sq->stats.syncp, start));
+		idx += VIRTNET_SQ_STATS_LEN;
+	}
+}
+
+static void virtnet_get_channels(struct net_device *dev,
+				 struct ethtool_channels *channels)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	channels->combined_count = vi->curr_queue_pairs;
+	channels->max_combined = vi->max_queue_pairs;
+	channels->max_other = 0;
+	channels->rx_count = 0;
+	channels->tx_count = 0;
+	channels->other_count = 0;
+}
+
+static int virtnet_set_link_ksettings(struct net_device *dev,
+				      const struct ethtool_link_ksettings *cmd)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	return ethtool_virtdev_set_link_ksettings(dev, cmd,
+						  &vi->speed, &vi->duplex);
+}
+
+static int virtnet_get_link_ksettings(struct net_device *dev,
+				      struct ethtool_link_ksettings *cmd)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	cmd->base.speed = vi->speed;
+	cmd->base.duplex = vi->duplex;
+	cmd->base.port = PORT_OTHER;
+
+	return 0;
+}
+
+static int virtnet_send_notf_coal_cmds(struct virtnet_info *vi,
+				       struct ethtool_coalesce *ec)
+{
+	struct scatterlist sgs_tx, sgs_rx;
+	int i;
+
+	vi->ctrl->coal_tx.tx_usecs = cpu_to_le32(ec->tx_coalesce_usecs);
+	vi->ctrl->coal_tx.tx_max_packets = cpu_to_le32(ec->tx_max_coalesced_frames);
+	sg_init_one(&sgs_tx, &vi->ctrl->coal_tx, sizeof(vi->ctrl->coal_tx));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
+				  VIRTIO_NET_CTRL_NOTF_COAL_TX_SET,
+				  &sgs_tx))
+		return -EINVAL;
+
+	/* Save parameters */
+	vi->intr_coal_tx.max_usecs = ec->tx_coalesce_usecs;
+	vi->intr_coal_tx.max_packets = ec->tx_max_coalesced_frames;
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		vi->sq[i].intr_coal.max_usecs = ec->tx_coalesce_usecs;
+		vi->sq[i].intr_coal.max_packets = ec->tx_max_coalesced_frames;
+	}
+
+	vi->ctrl->coal_rx.rx_usecs = cpu_to_le32(ec->rx_coalesce_usecs);
+	vi->ctrl->coal_rx.rx_max_packets = cpu_to_le32(ec->rx_max_coalesced_frames);
+	sg_init_one(&sgs_rx, &vi->ctrl->coal_rx, sizeof(vi->ctrl->coal_rx));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
+				  VIRTIO_NET_CTRL_NOTF_COAL_RX_SET,
+				  &sgs_rx))
+		return -EINVAL;
+
+	/* Save parameters */
+	vi->intr_coal_rx.max_usecs = ec->rx_coalesce_usecs;
+	vi->intr_coal_rx.max_packets = ec->rx_max_coalesced_frames;
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		vi->rq[i].intr_coal.max_usecs = ec->rx_coalesce_usecs;
+		vi->rq[i].intr_coal.max_packets = ec->rx_max_coalesced_frames;
+	}
+
+	return 0;
+}
+
+static int virtnet_send_ctrl_coal_vq_cmd(struct virtnet_info *vi,
+					 u16 vqn, u32 max_usecs, u32 max_packets)
+{
+	struct scatterlist sgs;
+
+	vi->ctrl->coal_vq.vqn = cpu_to_le16(vqn);
+	vi->ctrl->coal_vq.coal.max_usecs = cpu_to_le32(max_usecs);
+	vi->ctrl->coal_vq.coal.max_packets = cpu_to_le32(max_packets);
+	sg_init_one(&sgs, &vi->ctrl->coal_vq, sizeof(vi->ctrl->coal_vq));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
+				  VIRTIO_NET_CTRL_NOTF_COAL_VQ_SET,
+				  &sgs))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi,
+					  struct ethtool_coalesce *ec,
+					  u16 queue)
+{
+	int err;
+
+	err = virtnet_send_ctrl_coal_vq_cmd(vi, rxq2vq(queue),
+					    ec->rx_coalesce_usecs,
+					    ec->rx_max_coalesced_frames);
+	if (err)
+		return err;
+
+	vi->rq[queue].intr_coal.max_usecs = ec->rx_coalesce_usecs;
+	vi->rq[queue].intr_coal.max_packets = ec->rx_max_coalesced_frames;
+
+	err = virtnet_send_ctrl_coal_vq_cmd(vi, txq2vq(queue),
+					    ec->tx_coalesce_usecs,
+					    ec->tx_max_coalesced_frames);
+	if (err)
+		return err;
+
+	vi->sq[queue].intr_coal.max_usecs = ec->tx_coalesce_usecs;
+	vi->sq[queue].intr_coal.max_packets = ec->tx_max_coalesced_frames;
+
+	return 0;
+}
+
+static int virtnet_coal_params_supported(struct ethtool_coalesce *ec)
+{
+	/* usecs coalescing is supported only if VIRTIO_NET_F_NOTF_COAL
+	 * feature is negotiated.
+	 */
+	if (ec->rx_coalesce_usecs || ec->tx_coalesce_usecs)
+		return -EOPNOTSUPP;
+
+	if (ec->tx_max_coalesced_frames > 1 ||
+	    ec->rx_max_coalesced_frames != 1)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int virtnet_should_update_vq_weight(int dev_flags, int weight,
+					   int vq_weight, bool *should_update)
+{
+	if (weight ^ vq_weight) {
+		if (dev_flags & IFF_UP)
+			return -EBUSY;
+		*should_update = true;
+	}
+
+	return 0;
+}
+
+static int virtnet_set_coalesce(struct net_device *dev,
+				struct ethtool_coalesce *ec,
+				struct kernel_ethtool_coalesce *kernel_coal,
+				struct netlink_ext_ack *extack)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int ret, queue_number, napi_weight;
+	bool update_napi = false;
+
+	/* Can't change NAPI weight if the link is up */
+	napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
+	for (queue_number = 0; queue_number < vi->max_queue_pairs; queue_number++) {
+		ret = virtnet_should_update_vq_weight(dev->flags, napi_weight,
+						      vi->sq[queue_number].napi.weight,
+						      &update_napi);
+		if (ret)
+			return ret;
+
+		if (update_napi) {
+			/* All queues that belong to [queue_number, vi->max_queue_pairs] will be
+			 * updated for the sake of simplicity, which might not be necessary
+			 */
+			break;
+		}
+	}
+
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL))
+		ret = virtnet_send_notf_coal_cmds(vi, ec);
+	else
+		ret = virtnet_coal_params_supported(ec);
+
+	if (ret)
+		return ret;
+
+	if (update_napi) {
+		for (; queue_number < vi->max_queue_pairs; queue_number++)
+			vi->sq[queue_number].napi.weight = napi_weight;
+	}
+
+	return ret;
+}
+
+static int virtnet_get_coalesce(struct net_device *dev,
+				struct ethtool_coalesce *ec,
+				struct kernel_ethtool_coalesce *kernel_coal,
+				struct netlink_ext_ack *extack)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) {
+		ec->rx_coalesce_usecs = vi->intr_coal_rx.max_usecs;
+		ec->tx_coalesce_usecs = vi->intr_coal_tx.max_usecs;
+		ec->tx_max_coalesced_frames = vi->intr_coal_tx.max_packets;
+		ec->rx_max_coalesced_frames = vi->intr_coal_rx.max_packets;
+	} else {
+		ec->rx_max_coalesced_frames = 1;
+
+		if (vi->sq[0].napi.weight)
+			ec->tx_max_coalesced_frames = 1;
+	}
+
+	return 0;
+}
+
+static int virtnet_set_per_queue_coalesce(struct net_device *dev,
+					  u32 queue,
+					  struct ethtool_coalesce *ec)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int ret, napi_weight;
+	bool update_napi = false;
+
+	if (queue >= vi->max_queue_pairs)
+		return -EINVAL;
+
+	/* Can't change NAPI weight if the link is up */
+	napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
+	ret = virtnet_should_update_vq_weight(dev->flags, napi_weight,
+					      vi->sq[queue].napi.weight,
+					      &update_napi);
+	if (ret)
+		return ret;
+
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL))
+		ret = virtnet_send_notf_coal_vq_cmds(vi, ec, queue);
+	else
+		ret = virtnet_coal_params_supported(ec);
+
+	if (ret)
+		return ret;
+
+	if (update_napi)
+		vi->sq[queue].napi.weight = napi_weight;
+
+	return 0;
+}
+
+static int virtnet_get_per_queue_coalesce(struct net_device *dev,
+					  u32 queue,
+					  struct ethtool_coalesce *ec)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	if (queue >= vi->max_queue_pairs)
+		return -EINVAL;
+
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) {
+		ec->rx_coalesce_usecs = vi->rq[queue].intr_coal.max_usecs;
+		ec->tx_coalesce_usecs = vi->sq[queue].intr_coal.max_usecs;
+		ec->tx_max_coalesced_frames = vi->sq[queue].intr_coal.max_packets;
+		ec->rx_max_coalesced_frames = vi->rq[queue].intr_coal.max_packets;
+	} else {
+		ec->rx_max_coalesced_frames = 1;
+
+		if (vi->sq[queue].napi.weight)
+			ec->tx_max_coalesced_frames = 1;
+	}
+
+	return 0;
+}
+
+static void virtnet_init_settings(struct net_device *dev)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	vi->speed = SPEED_UNKNOWN;
+	vi->duplex = DUPLEX_UNKNOWN;
+}
+
+static void virtnet_update_settings(struct virtnet_info *vi)
+{
+	u32 speed;
+	u8 duplex;
+
+	if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX))
+		return;
+
+	virtio_cread_le(vi->vdev, struct virtio_net_config, speed, &speed);
+
+	if (ethtool_validate_speed(speed))
+		vi->speed = speed;
+
+	virtio_cread_le(vi->vdev, struct virtio_net_config, duplex, &duplex);
+
+	if (ethtool_validate_duplex(duplex))
+		vi->duplex = duplex;
+}
+
+static u32 virtnet_get_rxfh_key_size(struct net_device *dev)
+{
+	return ((struct virtnet_info *)netdev_priv(dev))->rss_key_size;
+}
+
+static u32 virtnet_get_rxfh_indir_size(struct net_device *dev)
+{
+	return ((struct virtnet_info *)netdev_priv(dev))->rss_indir_table_size;
+}
+
+static int virtnet_get_rxfh(struct net_device *dev, u32 *indir, u8 *key, u8 *hfunc)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int i;
+
+	if (indir) {
+		for (i = 0; i < vi->rss_indir_table_size; ++i)
+			indir[i] = vi->ctrl->rss.indirection_table[i];
+	}
+
+	if (key)
+		memcpy(key, vi->ctrl->rss.key, vi->rss_key_size);
+
+	if (hfunc)
+		*hfunc = ETH_RSS_HASH_TOP;
+
+	return 0;
+}
+
+static int virtnet_set_rxfh(struct net_device *dev, const u32 *indir, const u8 *key, const u8 hfunc)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int i;
+
+	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
+		return -EOPNOTSUPP;
+
+	if (indir) {
+		for (i = 0; i < vi->rss_indir_table_size; ++i)
+			vi->ctrl->rss.indirection_table[i] = indir[i];
+	}
+	if (key)
+		memcpy(vi->ctrl->rss.key, key, vi->rss_key_size);
+
+	virtnet_commit_rss_command(vi);
+
+	return 0;
+}
+
+static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info, u32 *rule_locs)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int rc = 0;
+
+	switch (info->cmd) {
+	case ETHTOOL_GRXRINGS:
+		info->data = vi->curr_queue_pairs;
+		break;
+	case ETHTOOL_GRXFH:
+		virtnet_get_hashflow(vi, info);
+		break;
+	default:
+		rc = -EOPNOTSUPP;
+	}
+
+	return rc;
+}
+
+static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int rc = 0;
+
+	switch (info->cmd) {
+	case ETHTOOL_SRXFH:
+		if (!virtnet_set_hashflow(vi, info))
+			rc = -EINVAL;
+
+		break;
+	default:
+		rc = -EOPNOTSUPP;
+	}
+
+	return rc;
+}
+
+static const struct ethtool_ops virtnet_ethtool_ops = {
+	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES |
+		ETHTOOL_COALESCE_USECS,
+	.get_drvinfo = virtnet_get_drvinfo,
+	.get_link = ethtool_op_get_link,
+	.get_ringparam = virtnet_get_ringparam,
+	.set_ringparam = virtnet_set_ringparam,
+	.get_strings = virtnet_get_strings,
+	.get_sset_count = virtnet_get_sset_count,
+	.get_ethtool_stats = virtnet_get_ethtool_stats,
+	.set_channels = virtnet_set_channels,
+	.get_channels = virtnet_get_channels,
+	.get_ts_info = ethtool_op_get_ts_info,
+	.get_link_ksettings = virtnet_get_link_ksettings,
+	.set_link_ksettings = virtnet_set_link_ksettings,
+	.set_coalesce = virtnet_set_coalesce,
+	.get_coalesce = virtnet_get_coalesce,
+	.set_per_queue_coalesce = virtnet_set_per_queue_coalesce,
+	.get_per_queue_coalesce = virtnet_get_per_queue_coalesce,
+	.get_rxfh_key_size = virtnet_get_rxfh_key_size,
+	.get_rxfh_indir_size = virtnet_get_rxfh_indir_size,
+	.get_rxfh = virtnet_get_rxfh,
+	.set_rxfh = virtnet_set_rxfh,
+	.get_rxnfc = virtnet_get_rxnfc,
+	.set_rxnfc = virtnet_set_rxnfc,
+};
+
+static void virtnet_freeze_down(struct virtio_device *vdev)
+{
+	struct virtnet_info *vi = vdev->priv;
+
+	/* Make sure no work handler is accessing the device */
+	flush_work(&vi->config_work);
+
+	netif_tx_lock_bh(vi->dev);
+	netif_device_detach(vi->dev);
+	netif_tx_unlock_bh(vi->dev);
+	if (netif_running(vi->dev))
+		virtnet_close(vi->dev);
+}
+
+static int init_vqs(struct virtnet_info *vi);
+
+static int virtnet_restore_up(struct virtio_device *vdev)
+{
+	struct virtnet_info *vi = vdev->priv;
+	int err;
+
+	err = init_vqs(vi);
+	if (err)
+		return err;
+
+	virtio_device_ready(vdev);
+
+	enable_delayed_refill(vi);
+
+	if (netif_running(vi->dev)) {
+		err = virtnet_open(vi->dev);
+		if (err)
+			return err;
+	}
+
+	netif_tx_lock_bh(vi->dev);
+	netif_device_attach(vi->dev);
+	netif_tx_unlock_bh(vi->dev);
+	return err;
+}
+
+static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads)
+{
+	struct scatterlist sg;
+	vi->ctrl->offloads = cpu_to_virtio64(vi->vdev, offloads);
+
+	sg_init_one(&sg, &vi->ctrl->offloads, sizeof(vi->ctrl->offloads));
+
+	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
+				  VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) {
+		dev_warn(&vi->dev->dev, "Fail to set guest offload.\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int virtnet_clear_guest_offloads(struct virtnet_info *vi)
+{
+	u64 offloads = 0;
+
+	if (!vi->guest_offloads)
+		return 0;
+
+	return virtnet_set_guest_offloads(vi, offloads);
+}
+
+static int virtnet_restore_guest_offloads(struct virtnet_info *vi)
+{
+	u64 offloads = vi->guest_offloads;
+
+	if (!vi->guest_offloads)
+		return 0;
+
+	return virtnet_set_guest_offloads(vi, offloads);
+}
+
+static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
+			   struct netlink_ext_ack *extack)
+{
+	unsigned int room = SKB_DATA_ALIGN(VIRTIO_XDP_HEADROOM +
+					   sizeof(struct skb_shared_info));
+	unsigned int max_sz = PAGE_SIZE - room - ETH_HLEN;
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct bpf_prog *old_prog;
+	u16 xdp_qp = 0, curr_qp;
+	int i, err;
+
+	if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)
+	    && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
+	        virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
+	        virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
+		virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) ||
+		virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM) ||
+		virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO4) ||
+		virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO6))) {
+		NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing GRO_HW/CSUM, disable GRO_HW/CSUM first");
+		return -EOPNOTSUPP;
+	}
+
+	if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
+		NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required");
+		return -EINVAL;
+	}
+
+	if (prog && !prog->aux->xdp_has_frags && dev->mtu > max_sz) {
+		NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP without frags");
+		netdev_warn(dev, "single-buffer XDP requires MTU less than %u\n", max_sz);
+		return -EINVAL;
+	}
+
+	curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
+	if (prog)
+		xdp_qp = nr_cpu_ids;
+
+	/* XDP requires extra queues for XDP_TX */
+	if (curr_qp + xdp_qp > vi->max_queue_pairs) {
+		netdev_warn_once(dev, "XDP request %i queues but max is %i. XDP_TX and XDP_REDIRECT will operate in a slower locked tx mode.\n",
+				 curr_qp + xdp_qp, vi->max_queue_pairs);
+		xdp_qp = 0;
+	}
+
+	old_prog = rtnl_dereference(vi->rq[0].xdp_prog);
+	if (!prog && !old_prog)
+		return 0;
+
+	if (prog)
+		bpf_prog_add(prog, vi->max_queue_pairs - 1);
+
+	/* Make sure NAPI is not using any XDP TX queues for RX. */
+	if (netif_running(dev)) {
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			napi_disable(&vi->rq[i].napi);
+			virtnet_napi_tx_disable(&vi->sq[i].napi);
+		}
+	}
+
+	if (!prog) {
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
+			if (i == 0)
+				virtnet_restore_guest_offloads(vi);
+		}
+		synchronize_net();
+	}
+
+	err = _virtnet_set_queues(vi, curr_qp + xdp_qp);
+	if (err)
+		goto err;
+	netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
+	vi->xdp_queue_pairs = xdp_qp;
+
+	if (prog) {
+		vi->xdp_enabled = true;
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
+			if (i == 0 && !old_prog)
+				virtnet_clear_guest_offloads(vi);
+		}
+		if (!old_prog)
+			xdp_features_set_redirect_target(dev, true);
+	} else {
+		xdp_features_clear_redirect_target(dev);
+		vi->xdp_enabled = false;
+	}
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		if (old_prog)
+			bpf_prog_put(old_prog);
+		if (netif_running(dev)) {
+			virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
+			virtnet_napi_tx_enable(vi, vi->sq[i].vq,
+					       &vi->sq[i].napi);
+		}
+	}
+
+	return 0;
+
+err:
+	if (!prog) {
+		virtnet_clear_guest_offloads(vi);
+		for (i = 0; i < vi->max_queue_pairs; i++)
+			rcu_assign_pointer(vi->rq[i].xdp_prog, old_prog);
+	}
+
+	if (netif_running(dev)) {
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
+			virtnet_napi_tx_enable(vi, vi->sq[i].vq,
+					       &vi->sq[i].napi);
+		}
+	}
+	if (prog)
+		bpf_prog_sub(prog, vi->max_queue_pairs - 1);
+	return err;
+}
+
+static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
+{
+	switch (xdp->command) {
+	case XDP_SETUP_PROG:
+		return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int virtnet_get_phys_port_name(struct net_device *dev, char *buf,
+				      size_t len)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	int ret;
+
+	if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY))
+		return -EOPNOTSUPP;
+
+	ret = snprintf(buf, len, "sby");
+	if (ret >= len)
+		return -EOPNOTSUPP;
+
+	return 0;
+}
+
+static int virtnet_set_features(struct net_device *dev,
+				netdev_features_t features)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	u64 offloads;
+	int err;
+
+	if ((dev->features ^ features) & NETIF_F_GRO_HW) {
+		if (vi->xdp_enabled)
+			return -EBUSY;
+
+		if (features & NETIF_F_GRO_HW)
+			offloads = vi->guest_offloads_capable;
+		else
+			offloads = vi->guest_offloads_capable &
+				   ~GUEST_OFFLOAD_GRO_HW_MASK;
+
+		err = virtnet_set_guest_offloads(vi, offloads);
+		if (err)
+			return err;
+		vi->guest_offloads = offloads;
+	}
+
+	if ((dev->features ^ features) & NETIF_F_RXHASH) {
+		if (features & NETIF_F_RXHASH)
+			vi->ctrl->rss.hash_types = vi->rss_hash_types_saved;
+		else
+			vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE;
+
+		if (!virtnet_commit_rss_command(vi))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void virtnet_tx_timeout(struct net_device *dev, unsigned int txqueue)
+{
+	struct virtnet_info *priv = netdev_priv(dev);
+	struct send_queue *sq = &priv->sq[txqueue];
+	struct netdev_queue *txq = netdev_get_tx_queue(dev, txqueue);
+
+	u64_stats_update_begin(&sq->stats.syncp);
+	u64_stats_inc(&sq->stats.tx_timeouts);
+	u64_stats_update_end(&sq->stats.syncp);
+
+	netdev_err(dev, "TX timeout on queue: %u, sq: %s, vq: 0x%x, name: %s, %u usecs ago\n",
+		   txqueue, sq->name, sq->vq->index, sq->vq->name,
+		   jiffies_to_usecs(jiffies - READ_ONCE(txq->trans_start)));
+}
+
+static const struct net_device_ops virtnet_netdev = {
+	.ndo_open            = virtnet_open,
+	.ndo_stop   	     = virtnet_close,
+	.ndo_start_xmit      = start_xmit,
+	.ndo_validate_addr   = eth_validate_addr,
+	.ndo_set_mac_address = virtnet_set_mac_address,
+	.ndo_set_rx_mode     = virtnet_set_rx_mode,
+	.ndo_get_stats64     = virtnet_stats,
+	.ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
+	.ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
+	.ndo_bpf		= virtnet_xdp,
+	.ndo_xdp_xmit		= virtnet_xdp_xmit,
+	.ndo_features_check	= passthru_features_check,
+	.ndo_get_phys_port_name	= virtnet_get_phys_port_name,
+	.ndo_set_features	= virtnet_set_features,
+	.ndo_tx_timeout		= virtnet_tx_timeout,
+};
+
+static void virtnet_config_changed_work(struct work_struct *work)
+{
+	struct virtnet_info *vi =
+		container_of(work, struct virtnet_info, config_work);
+	u16 v;
+
+	if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
+				 struct virtio_net_config, status, &v) < 0)
+		return;
+
+	if (v & VIRTIO_NET_S_ANNOUNCE) {
+		netdev_notify_peers(vi->dev);
+		virtnet_ack_link_announce(vi);
+	}
+
+	/* Ignore unknown (future) status bits */
+	v &= VIRTIO_NET_S_LINK_UP;
+
+	if (vi->status == v)
+		return;
+
+	vi->status = v;
+
+	if (vi->status & VIRTIO_NET_S_LINK_UP) {
+		virtnet_update_settings(vi);
+		netif_carrier_on(vi->dev);
+		netif_tx_wake_all_queues(vi->dev);
+	} else {
+		netif_carrier_off(vi->dev);
+		netif_tx_stop_all_queues(vi->dev);
+	}
+}
+
+static void virtnet_config_changed(struct virtio_device *vdev)
+{
+	struct virtnet_info *vi = vdev->priv;
+
+	schedule_work(&vi->config_work);
+}
+
+static void virtnet_free_queues(struct virtnet_info *vi)
+{
+	int i;
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		__netif_napi_del(&vi->rq[i].napi);
+		__netif_napi_del(&vi->sq[i].napi);
+	}
+
+	/* We called __netif_napi_del(),
+	 * we need to respect an RCU grace period before freeing vi->rq
+	 */
+	synchronize_net();
+
+	kfree(vi->rq);
+	kfree(vi->sq);
+	kfree(vi->ctrl);
+}
+
+static void _free_receive_bufs(struct virtnet_info *vi)
+{
+	struct bpf_prog *old_prog;
+	int i;
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		while (vi->rq[i].pages)
+			__free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
+
+		old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
+		RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
+		if (old_prog)
+			bpf_prog_put(old_prog);
+	}
+}
+
+static void free_receive_bufs(struct virtnet_info *vi)
+{
+	rtnl_lock();
+	_free_receive_bufs(vi);
+	rtnl_unlock();
+}
+
+static void free_receive_page_frags(struct virtnet_info *vi)
+{
+	int i;
+	for (i = 0; i < vi->max_queue_pairs; i++)
+		if (vi->rq[i].alloc_frag.page) {
+			if (vi->rq[i].do_dma && vi->rq[i].last_dma)
+				virtnet_rq_unmap(&vi->rq[i], vi->rq[i].last_dma, 0);
+			put_page(vi->rq[i].alloc_frag.page);
+		}
+}
+
+static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf)
+{
+	if (!is_xdp_frame(buf))
+		dev_kfree_skb(buf);
+	else
+		xdp_return_frame(ptr_to_xdp(buf));
+}
+
+static void free_unused_bufs(struct virtnet_info *vi)
+{
+	void *buf;
+	int i;
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		struct virtqueue *vq = vi->sq[i].vq;
+		while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
+			virtnet_sq_free_unused_buf(vq, buf);
+		cond_resched();
+	}
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		struct virtqueue *vq = vi->rq[i].vq;
+
+		while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
+			virtnet_rq_unmap_free_buf(vq, buf);
+		cond_resched();
+	}
+}
+
+static void virtnet_del_vqs(struct virtnet_info *vi)
+{
+	struct virtio_device *vdev = vi->vdev;
+
+	virtnet_clean_affinity(vi);
+
+	vdev->config->del_vqs(vdev);
+
+	virtnet_free_queues(vi);
+}
+
+/* How large should a single buffer be so a queue full of these can fit at
+ * least one full packet?
+ * Logic below assumes the mergeable buffer header is used.
+ */
+static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq)
+{
+	const unsigned int hdr_len = vi->hdr_len;
+	unsigned int rq_size = virtqueue_get_vring_size(vq);
+	unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu;
+	unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len;
+	unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size);
+
+	return max(max(min_buf_len, hdr_len) - hdr_len,
+		   (unsigned int)GOOD_PACKET_LEN);
+}
+
+static int virtnet_find_vqs(struct virtnet_info *vi)
+{
+	vq_callback_t **callbacks;
+	struct virtqueue **vqs;
+	int ret = -ENOMEM;
+	int i, total_vqs;
+	const char **names;
+	bool *ctx;
+
+	/* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
+	 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
+	 * possible control vq.
+	 */
+	total_vqs = vi->max_queue_pairs * 2 +
+		    virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
+
+	/* Allocate space for find_vqs parameters */
+	vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL);
+	if (!vqs)
+		goto err_vq;
+	callbacks = kmalloc_array(total_vqs, sizeof(*callbacks), GFP_KERNEL);
+	if (!callbacks)
+		goto err_callback;
+	names = kmalloc_array(total_vqs, sizeof(*names), GFP_KERNEL);
+	if (!names)
+		goto err_names;
+	if (!vi->big_packets || vi->mergeable_rx_bufs) {
+		ctx = kcalloc(total_vqs, sizeof(*ctx), GFP_KERNEL);
+		if (!ctx)
+			goto err_ctx;
+	} else {
+		ctx = NULL;
+	}
+
+	/* Parameters for control virtqueue, if any */
+	if (vi->has_cvq) {
+		callbacks[total_vqs - 1] = NULL;
+		names[total_vqs - 1] = "control";
+	}
+
+	/* Allocate/initialize parameters for send/receive virtqueues */
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		callbacks[rxq2vq(i)] = skb_recv_done;
+		callbacks[txq2vq(i)] = skb_xmit_done;
+		sprintf(vi->rq[i].name, "input.%d", i);
+		sprintf(vi->sq[i].name, "output.%d", i);
+		names[rxq2vq(i)] = vi->rq[i].name;
+		names[txq2vq(i)] = vi->sq[i].name;
+		if (ctx)
+			ctx[rxq2vq(i)] = true;
+	}
+
+	ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks,
+				  names, ctx, NULL);
+	if (ret)
+		goto err_find;
+
+	if (vi->has_cvq) {
+		vi->cvq = vqs[total_vqs - 1];
+		if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
+			vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
+	}
+
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		vi->rq[i].vq = vqs[rxq2vq(i)];
+		vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
+		vi->sq[i].vq = vqs[txq2vq(i)];
+	}
+
+	/* run here: ret == 0. */
+
+
+err_find:
+	kfree(ctx);
+err_ctx:
+	kfree(names);
+err_names:
+	kfree(callbacks);
+err_callback:
+	kfree(vqs);
+err_vq:
+	return ret;
+}
+
+static int virtnet_alloc_queues(struct virtnet_info *vi)
+{
+	int i;
+
+	if (vi->has_cvq) {
+		vi->ctrl = kzalloc(sizeof(*vi->ctrl), GFP_KERNEL);
+		if (!vi->ctrl)
+			goto err_ctrl;
+	} else {
+		vi->ctrl = NULL;
+	}
+	vi->sq = kcalloc(vi->max_queue_pairs, sizeof(*vi->sq), GFP_KERNEL);
+	if (!vi->sq)
+		goto err_sq;
+	vi->rq = kcalloc(vi->max_queue_pairs, sizeof(*vi->rq), GFP_KERNEL);
+	if (!vi->rq)
+		goto err_rq;
+
+	INIT_DELAYED_WORK(&vi->refill, refill_work);
+	for (i = 0; i < vi->max_queue_pairs; i++) {
+		vi->rq[i].pages = NULL;
+		netif_napi_add_weight(vi->dev, &vi->rq[i].napi, virtnet_poll,
+				      napi_weight);
+		netif_napi_add_tx_weight(vi->dev, &vi->sq[i].napi,
+					 virtnet_poll_tx,
+					 napi_tx ? napi_weight : 0);
+
+		sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
+		ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
+		sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
+
+		u64_stats_init(&vi->rq[i].stats.syncp);
+		u64_stats_init(&vi->sq[i].stats.syncp);
+	}
+
+	return 0;
+
+err_rq:
+	kfree(vi->sq);
+err_sq:
+	kfree(vi->ctrl);
+err_ctrl:
+	return -ENOMEM;
+}
+
+static int init_vqs(struct virtnet_info *vi)
+{
+	int ret;
+
+	/* Allocate send & receive queues */
+	ret = virtnet_alloc_queues(vi);
+	if (ret)
+		goto err;
+
+	ret = virtnet_find_vqs(vi);
+	if (ret)
+		goto err_free;
+
+	virtnet_rq_set_premapped(vi);
+
+	cpus_read_lock();
+	virtnet_set_affinity(vi);
+	cpus_read_unlock();
+
+	return 0;
+
+err_free:
+	virtnet_free_queues(vi);
+err:
+	return ret;
+}
+
+#ifdef CONFIG_SYSFS
+static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
+		char *buf)
+{
+	struct virtnet_info *vi = netdev_priv(queue->dev);
+	unsigned int queue_index = get_netdev_rx_queue_index(queue);
+	unsigned int headroom = virtnet_get_headroom(vi);
+	unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
+	struct ewma_pkt_len *avg;
+
+	BUG_ON(queue_index >= vi->max_queue_pairs);
+	avg = &vi->rq[queue_index].mrg_avg_pkt_len;
+	return sprintf(buf, "%u\n",
+		       get_mergeable_buf_len(&vi->rq[queue_index], avg,
+				       SKB_DATA_ALIGN(headroom + tailroom)));
+}
+
+static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
+	__ATTR_RO(mergeable_rx_buffer_size);
+
+static struct attribute *virtio_net_mrg_rx_attrs[] = {
+	&mergeable_rx_buffer_size_attribute.attr,
+	NULL
+};
+
+static const struct attribute_group virtio_net_mrg_rx_group = {
+	.name = "virtio_net",
+	.attrs = virtio_net_mrg_rx_attrs
+};
+#endif
+
+static bool virtnet_fail_on_feature(struct virtio_device *vdev,
+				    unsigned int fbit,
+				    const char *fname, const char *dname)
+{
+	if (!virtio_has_feature(vdev, fbit))
+		return false;
+
+	dev_err(&vdev->dev, "device advertises feature %s but not %s",
+		fname, dname);
+
+	return true;
+}
+
+#define VIRTNET_FAIL_ON(vdev, fbit, dbit)			\
+	virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
+
+static bool virtnet_validate_features(struct virtio_device *vdev)
+{
+	if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
+	    (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS,
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_NOTF_COAL,
+			     "VIRTIO_NET_F_CTRL_VQ") ||
+	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_VQ_NOTF_COAL,
+			     "VIRTIO_NET_F_CTRL_VQ"))) {
+		return false;
+	}
+
+	return true;
+}
+
+#define MIN_MTU ETH_MIN_MTU
+#define MAX_MTU ETH_MAX_MTU
+
+static int virtnet_validate(struct virtio_device *vdev)
+{
+	if (!vdev->config->get) {
+		dev_err(&vdev->dev, "%s failure: config access disabled\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	if (!virtnet_validate_features(vdev))
+		return -EINVAL;
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
+		int mtu = virtio_cread16(vdev,
+					 offsetof(struct virtio_net_config,
+						  mtu));
+		if (mtu < MIN_MTU)
+			__virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
+	}
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY) &&
+	    !virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
+		dev_warn(&vdev->dev, "device advertises feature VIRTIO_NET_F_STANDBY but not VIRTIO_NET_F_MAC, disabling standby");
+		__virtio_clear_bit(vdev, VIRTIO_NET_F_STANDBY);
+	}
+
+	return 0;
+}
+
+static bool virtnet_check_guest_gso(const struct virtnet_info *vi)
+{
+	return virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
+		virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
+		virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
+		virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) ||
+		(virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO4) &&
+		virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO6));
+}
+
+static void virtnet_set_big_packets(struct virtnet_info *vi, const int mtu)
+{
+	bool guest_gso = virtnet_check_guest_gso(vi);
+
+	/* If device can receive ANY guest GSO packets, regardless of mtu,
+	 * allocate packets of maximum size, otherwise limit it to only
+	 * mtu size worth only.
+	 */
+	if (mtu > ETH_DATA_LEN || guest_gso) {
+		vi->big_packets = true;
+		vi->big_packets_num_skbfrags = guest_gso ? MAX_SKB_FRAGS : DIV_ROUND_UP(mtu, PAGE_SIZE);
+	}
+}
+
+static int virtnet_probe(struct virtio_device *vdev)
+{
+	int i, err = -ENOMEM;
+	struct net_device *dev;
+	struct virtnet_info *vi;
+	u16 max_queue_pairs;
+	int mtu = 0;
+
+	/* Find if host supports multiqueue/rss virtio_net device */
+	max_queue_pairs = 1;
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_MQ) || virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
+		max_queue_pairs =
+		     virtio_cread16(vdev, offsetof(struct virtio_net_config, max_virtqueue_pairs));
+
+	/* We need at least 2 queue's */
+	if (max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
+	    max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
+	    !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
+		max_queue_pairs = 1;
+
+	/* Allocate ourselves a network device with room for our info */
+	dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
+	if (!dev)
+		return -ENOMEM;
+
+	/* Set up network device as normal. */
+	dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE |
+			   IFF_TX_SKB_NO_LINEAR;
+	dev->netdev_ops = &virtnet_netdev;
+	dev->features = NETIF_F_HIGHDMA;
+
+	dev->ethtool_ops = &virtnet_ethtool_ops;
+	SET_NETDEV_DEV(dev, &vdev->dev);
+
+	/* Do we support "hardware" checksums? */
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
+		/* This opens up the world of extra features. */
+		dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
+		if (csum)
+			dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
+
+		if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
+			dev->hw_features |= NETIF_F_TSO
+				| NETIF_F_TSO_ECN | NETIF_F_TSO6;
+		}
+		/* Individual feature bits: what can host handle? */
+		if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
+			dev->hw_features |= NETIF_F_TSO;
+		if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
+			dev->hw_features |= NETIF_F_TSO6;
+		if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
+			dev->hw_features |= NETIF_F_TSO_ECN;
+		if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_USO))
+			dev->hw_features |= NETIF_F_GSO_UDP_L4;
+
+		dev->features |= NETIF_F_GSO_ROBUST;
+
+		if (gso)
+			dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
+		/* (!csum && gso) case will be fixed by register_netdev() */
+	}
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
+		dev->features |= NETIF_F_RXCSUM;
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
+	    virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6))
+		dev->features |= NETIF_F_GRO_HW;
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS))
+		dev->hw_features |= NETIF_F_GRO_HW;
+
+	dev->vlan_features = dev->features;
+	dev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT;
+
+	/* MTU range: 68 - 65535 */
+	dev->min_mtu = MIN_MTU;
+	dev->max_mtu = MAX_MTU;
+
+	/* Configuration may specify what MAC to use.  Otherwise random. */
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
+		u8 addr[ETH_ALEN];
+
+		virtio_cread_bytes(vdev,
+				   offsetof(struct virtio_net_config, mac),
+				   addr, ETH_ALEN);
+		eth_hw_addr_set(dev, addr);
+	} else {
+		eth_hw_addr_random(dev);
+		dev_info(&vdev->dev, "Assigned random MAC address %pM\n",
+			 dev->dev_addr);
+	}
+
+	/* Set up our device-specific information */
+	vi = netdev_priv(dev);
+	vi->dev = dev;
+	vi->vdev = vdev;
+	vdev->priv = vi;
+
+	INIT_WORK(&vi->config_work, virtnet_config_changed_work);
+	spin_lock_init(&vi->refill_lock);
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) {
+		vi->mergeable_rx_bufs = true;
+		dev->xdp_features |= NETDEV_XDP_ACT_RX_SG;
+	}
+
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) {
+		vi->intr_coal_rx.max_usecs = 0;
+		vi->intr_coal_tx.max_usecs = 0;
+		vi->intr_coal_tx.max_packets = 0;
+		vi->intr_coal_rx.max_packets = 0;
+	}
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT))
+		vi->has_rss_hash_report = true;
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
+		vi->has_rss = true;
+
+	if (vi->has_rss || vi->has_rss_hash_report) {
+		vi->rss_indir_table_size =
+			virtio_cread16(vdev, offsetof(struct virtio_net_config,
+				rss_max_indirection_table_length));
+		vi->rss_key_size =
+			virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
+
+		vi->rss_hash_types_supported =
+		    virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
+		vi->rss_hash_types_supported &=
+				~(VIRTIO_NET_RSS_HASH_TYPE_IP_EX |
+				  VIRTIO_NET_RSS_HASH_TYPE_TCP_EX |
+				  VIRTIO_NET_RSS_HASH_TYPE_UDP_EX);
+
+		dev->hw_features |= NETIF_F_RXHASH;
+	}
+
+	if (vi->has_rss_hash_report)
+		vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);
+	else if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
+		 virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
+		vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	else
+		vi->hdr_len = sizeof(struct virtio_net_hdr);
+
+	if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
+	    virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
+		vi->any_header_sg = true;
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
+		vi->has_cvq = true;
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
+		mtu = virtio_cread16(vdev,
+				     offsetof(struct virtio_net_config,
+					      mtu));
+		if (mtu < dev->min_mtu) {
+			/* Should never trigger: MTU was previously validated
+			 * in virtnet_validate.
+			 */
+			dev_err(&vdev->dev,
+				"device MTU appears to have changed it is now %d < %d",
+				mtu, dev->min_mtu);
+			err = -EINVAL;
+			goto free;
+		}
+
+		dev->mtu = mtu;
+		dev->max_mtu = mtu;
+	}
+
+	virtnet_set_big_packets(vi, mtu);
+
+	if (vi->any_header_sg)
+		dev->needed_headroom = vi->hdr_len;
+
+	/* Enable multiqueue by default */
+	if (num_online_cpus() >= max_queue_pairs)
+		vi->curr_queue_pairs = max_queue_pairs;
+	else
+		vi->curr_queue_pairs = num_online_cpus();
+	vi->max_queue_pairs = max_queue_pairs;
+
+	/* Allocate/initialize the rx/tx queues, and invoke find_vqs */
+	err = init_vqs(vi);
+	if (err)
+		goto free;
+
+#ifdef CONFIG_SYSFS
+	if (vi->mergeable_rx_bufs)
+		dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
+#endif
+	netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
+	netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
+
+	virtnet_init_settings(dev);
+
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
+		vi->failover = net_failover_create(vi->dev);
+		if (IS_ERR(vi->failover)) {
+			err = PTR_ERR(vi->failover);
+			goto free_vqs;
+		}
+	}
+
+	if (vi->has_rss || vi->has_rss_hash_report)
+		virtnet_init_default_rss(vi);
+
+	/* serialize netdev register + virtio_device_ready() with ndo_open() */
+	rtnl_lock();
+
+	err = register_netdevice(dev);
+	if (err) {
+		pr_debug("virtio_net: registering device failed\n");
+		rtnl_unlock();
+		goto free_failover;
+	}
+
+	virtio_device_ready(vdev);
+
+	_virtnet_set_queues(vi, vi->curr_queue_pairs);
+
+	/* a random MAC address has been assigned, notify the device.
+	 * We don't fail probe if VIRTIO_NET_F_CTRL_MAC_ADDR is not there
+	 * because many devices work fine without getting MAC explicitly
+	 */
+	if (!virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
+	    virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
+		struct scatterlist sg;
+
+		sg_init_one(&sg, dev->dev_addr, dev->addr_len);
+		if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
+					  VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
+			pr_debug("virtio_net: setting MAC address failed\n");
+			rtnl_unlock();
+			err = -EINVAL;
+			goto free_unregister_netdev;
+		}
+	}
+
+	rtnl_unlock();
+
+	err = virtnet_cpu_notif_add(vi);
+	if (err) {
+		pr_debug("virtio_net: registering cpu notifier failed\n");
+		goto free_unregister_netdev;
+	}
+
+	/* Assume link up if device can't report link status,
+	   otherwise get link status from config. */
+	netif_carrier_off(dev);
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
+		schedule_work(&vi->config_work);
+	} else {
+		vi->status = VIRTIO_NET_S_LINK_UP;
+		virtnet_update_settings(vi);
+		netif_carrier_on(dev);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
+		if (virtio_has_feature(vi->vdev, guest_offloads[i]))
+			set_bit(guest_offloads[i], &vi->guest_offloads);
+	vi->guest_offloads_capable = vi->guest_offloads;
+
+	pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
+		 dev->name, max_queue_pairs);
+
+	return 0;
+
+free_unregister_netdev:
+	unregister_netdev(dev);
+free_failover:
+	net_failover_destroy(vi->failover);
+free_vqs:
+	virtio_reset_device(vdev);
+	cancel_delayed_work_sync(&vi->refill);
+	free_receive_page_frags(vi);
+	virtnet_del_vqs(vi);
+free:
+	free_netdev(dev);
+	return err;
+}
+
+static void remove_vq_common(struct virtnet_info *vi)
+{
+	virtio_reset_device(vi->vdev);
+
+	/* Free unused buffers in both send and recv, if any. */
+	free_unused_bufs(vi);
+
+	free_receive_bufs(vi);
+
+	free_receive_page_frags(vi);
+
+	virtnet_del_vqs(vi);
+}
+
+static void virtnet_remove(struct virtio_device *vdev)
+{
+	struct virtnet_info *vi = vdev->priv;
+
+	virtnet_cpu_notif_remove(vi);
+
+	/* Make sure no work handler is accessing the device. */
+	flush_work(&vi->config_work);
+
+	unregister_netdev(vi->dev);
+
+	net_failover_destroy(vi->failover);
+
+	remove_vq_common(vi);
+
+	free_netdev(vi->dev);
+}
+
+static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
+{
+	struct virtnet_info *vi = vdev->priv;
+
+	virtnet_cpu_notif_remove(vi);
+	virtnet_freeze_down(vdev);
+	remove_vq_common(vi);
+
+	return 0;
+}
+
+static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
+{
+	struct virtnet_info *vi = vdev->priv;
+	int err;
+
+	err = virtnet_restore_up(vdev);
+	if (err)
+		return err;
+	virtnet_set_queues(vi, vi->curr_queue_pairs);
+
+	err = virtnet_cpu_notif_add(vi);
+	if (err) {
+		virtnet_freeze_down(vdev);
+		remove_vq_common(vi);
+		return err;
+	}
+
+	return 0;
+}
+
+static struct virtio_device_id id_table[] = {
+	{ VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
+	{ 0 },
+};
+
+#define VIRTNET_FEATURES \
+	VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
+	VIRTIO_NET_F_MAC, \
+	VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
+	VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
+	VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
+	VIRTIO_NET_F_HOST_USO, VIRTIO_NET_F_GUEST_USO4, VIRTIO_NET_F_GUEST_USO6, \
+	VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
+	VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
+	VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
+	VIRTIO_NET_F_CTRL_MAC_ADDR, \
+	VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
+	VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
+	VIRTIO_NET_F_RSS, VIRTIO_NET_F_HASH_REPORT, VIRTIO_NET_F_NOTF_COAL, \
+	VIRTIO_NET_F_VQ_NOTF_COAL, \
+	VIRTIO_NET_F_GUEST_HDRLEN
+
+static unsigned int features[] = {
+	VIRTNET_FEATURES,
+};
+
+static unsigned int features_legacy[] = {
+	VIRTNET_FEATURES,
+	VIRTIO_NET_F_GSO,
+	VIRTIO_F_ANY_LAYOUT,
+};
+
+static struct virtio_driver virtio_net_driver = {
+	.feature_table = features,
+	.feature_table_size = ARRAY_SIZE(features),
+	.feature_table_legacy = features_legacy,
+	.feature_table_size_legacy = ARRAY_SIZE(features_legacy),
+	.driver.name =	KBUILD_MODNAME,
+	.driver.owner =	THIS_MODULE,
+	.id_table =	id_table,
+	.validate =	virtnet_validate,
+	.probe =	virtnet_probe,
+	.remove =	virtnet_remove,
+	.config_changed = virtnet_config_changed,
+#ifdef CONFIG_PM_SLEEP
+	.freeze =	virtnet_freeze,
+	.restore =	virtnet_restore,
+#endif
+};
+
+static __init int virtio_net_driver_init(void)
+{
+	int ret;
+
+	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
+				      virtnet_cpu_online,
+				      virtnet_cpu_down_prep);
+	if (ret < 0)
+		goto out;
+	virtionet_online = ret;
+	ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
+				      NULL, virtnet_cpu_dead);
+	if (ret)
+		goto err_dead;
+	ret = register_virtio_driver(&virtio_net_driver);
+	if (ret)
+		goto err_virtio;
+	return 0;
+err_virtio:
+	cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
+err_dead:
+	cpuhp_remove_multi_state(virtionet_online);
+out:
+	return ret;
+}
+module_init(virtio_net_driver_init);
+
+static __exit void virtio_net_driver_exit(void)
+{
+	unregister_virtio_driver(&virtio_net_driver);
+	cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
+	cpuhp_remove_multi_state(virtionet_online);
+}
+module_exit(virtio_net_driver_exit);
+
+MODULE_DEVICE_TABLE(virtio, id_table);
+MODULE_DESCRIPTION("Virtio network driver");
+MODULE_LICENSE("GPL");