Release 4.11 drivers/net/virtio_net.c

Directory: drivers/net
/* A network driver using virtio.
 *
 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */
//#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>


static int napi_weight = NAPI_POLL_WEIGHT;
module_param(napi_weight, int, 0444);



static bool csum = true, gso = true;
module_param(csum, bool, 0444);
module_param(gso, bool, 0444);

/* 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

/* 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)

/* With mergeable buffers we align buffer address and use the low bits to
 * encode its true size. Buffer size is up to 1 page so we need to align to
 * square root of page size to ensure we reserve enough bits to encode the true
 * size.
 */

#define MERGEABLE_BUFFER_MIN_ALIGN_SHIFT ((PAGE_SHIFT + 1) / 2)

/* Minimum alignment for mergeable packet buffers. */

#define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, \
                                   1 << MERGEABLE_BUFFER_MIN_ALIGN_SHIFT)


#define VIRTNET_DRIVER_VERSION "1.0.0"


struct virtnet_stats {
	
struct u64_stats_sync tx_syncp;
	
struct u64_stats_sync rx_syncp;
	
u64 tx_bytes;
	
u64 tx_packets;

	
u64 rx_bytes;
	
u64 rx_packets;
};

/* 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[40];
};

/* 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;

	/* 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];

	/* Name of this receive queue: input.$index */
	
char name[40];
};


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;

	/* I like... big packets and I cannot lie! */
	
bool big_packets;

	/* Host will merge rx buffers for big packets (shake it! shake it!) */
	
bool mergeable_rx_bufs;

	/* 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;

	/* Active statistics */
	
struct virtnet_stats __percpu *stats;

	/* Work struct for refilling if we run low on memory. */
	
struct delayed_work refill;

	/* 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;

	/* Control VQ buffers: protected by the rtnl lock */
	
struct virtio_net_ctrl_hdr ctrl_hdr;
	
virtio_net_ctrl_ack ctrl_status;
	
struct virtio_net_ctrl_mq ctrl_mq;
	
u8 ctrl_promisc;
	
u8 ctrl_allmulti;
	
u16 ctrl_vid;

	/* Ethtool settings */
	
u8 duplex;
	
u32 speed;
};


struct padded_vnet_hdr {
	
struct virtio_net_hdr_mrg_rxbuf 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[4];
};

/* 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;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 20 90.91% 1 50.00%
Rusty Russell 2 9.09% 1 50.00%
Total 22 100.00% 2 100.00%



static int txq2vq(int txq)
{
	return txq * 2 + 1;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 16 100.00% 1 100.00%
Total 16 100.00% 1 100.00%



static int vq2rxq(struct virtqueue *vq)
{
	return vq->index / 2;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 16 88.89% 1 50.00%
Rusty Russell 2 11.11% 1 50.00%
Total 18 100.00% 2 100.00%



static int rxq2vq(int rxq)
{
	return rxq * 2;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 14 100.00% 1 100.00%
Total 14 100.00% 1 100.00%



static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
{
	return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 22 91.67% 2 66.67%
Michael S. Tsirkin 2 8.33% 1 33.33%
Total 24 100.00% 3 100.00%

/*
 * 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;
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 29 46.77% 1 33.33%
Shirley Ma 28 45.16% 1 33.33%
Jason (Hui) Wang 5 8.06% 1 33.33%
Total 62 100.00% 3 100.00%



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;
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 49 79.03% 1 33.33%
Shirley Ma 9 14.52% 1 33.33%
Jason (Hui) Wang 4 6.45% 1 33.33%
Total 62 100.00% 3 100.00%



static void skb_xmit_done(struct virtqueue *vq)
{
	struct virtnet_info *vi = vq->vdev->priv;

	/* Suppress further interrupts. */
	virtqueue_disable_cb(vq);

	/* We were probably waiting for more output buffers. */
	netif_wake_subqueue(vi->dev, vq2txq(vq));
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 31 75.61% 4 57.14%
Jason (Hui) Wang 9 21.95% 2 28.57%
Michael S. Tsirkin 1 2.44% 1 14.29%
Total 41 100.00% 7 100.00%



static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx)
{
	unsigned int truesize = mrg_ctx & (MERGEABLE_BUFFER_ALIGN - 1);
	return (truesize + 1) * MERGEABLE_BUFFER_ALIGN;
}

Contributors
Person Tokens Prop Commits CommitProp
Michael Dalton 32 100.00% 1 100.00%
Total 32 100.00% 1 100.00%



static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx)
{
	return (void *)(mrg_ctx & -MERGEABLE_BUFFER_ALIGN);

}

Contributors
Person Tokens Prop Commits CommitProp
Michael Dalton 23 100.00% 1 100.00%
Total 23 100.00% 1 100.00%



static unsigned long mergeable_buf_to_ctx(void *buf, unsigned int truesize)
{
	unsigned int size = truesize / MERGEABLE_BUFFER_ALIGN;
	return (unsigned long)buf | (size - 1);
}

Contributors
Person Tokens Prop Commits CommitProp
Michael Dalton 36 100.00% 1 100.00%
Total 36 100.00% 1 100.00%

/* 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)
{
	struct sk_buff *skb;
	struct virtio_net_hdr_mrg_rxbuf *hdr;
	unsigned int copy, hdr_len, hdr_padded_len;
	char *p;

	p = page_address(page) + offset;

	/* 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;

	hdr = skb_vnet_hdr(skb);

	hdr_len = vi->hdr_len;
	if (vi->mergeable_rx_bufs)
		hdr_padded_len = sizeof *hdr;
	else
		hdr_padded_len = sizeof(struct padded_vnet_hdr);

	memcpy(hdr, p, hdr_len);

	len -= hdr_len;
	offset += hdr_padded_len;
	p += hdr_padded_len;

	copy = len;
	if (copy > skb_tailroom(skb))
		copy = skb_tailroom(skb);
	memcpy(skb_put(skb, copy), p, copy);

	len -= copy;
	offset += copy;

	if (vi->mergeable_rx_bufs) {
		if (len)
			skb_add_rx_frag(skb, 0, page, offset, len, truesize);
		else
			put_page(page);
		return skb;
	}

	/*
         * 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);

	return skb;
}

Contributors
Person Tokens Prop Commits CommitProp
Shirley Ma 128 37.87% 1 7.14%
Michael Dalton 94 27.81% 1 7.14%
Mark McLoughlin 40 11.83% 1 7.14%
Sasha Levin 32 9.47% 1 7.14%
Michael S. Tsirkin 13 3.85% 2 14.29%
Rusty Russell 13 3.85% 3 21.43%
Herbert Xu 8 2.37% 1 7.14%
Paolo Abeni 4 1.18% 1 7.14%
Jason (Hui) Wang 3 0.89% 1 7.14%
Wang Chen 2 0.59% 1 7.14%
Américo Wang 1 0.30% 1 7.14%
Total 338 100.00% 14 100.00%



static bool virtnet_xdp_xmit(struct virtnet_info *vi,
			     struct receive_queue *rq,
			     struct xdp_buff *xdp)
{
	struct virtio_net_hdr_mrg_rxbuf *hdr;
	unsigned int len;
	struct send_queue *sq;
	unsigned int qp;
	void *xdp_sent;
	int err;

	qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
	sq = &vi->sq[qp];

	/* Free up any pending old buffers before queueing new ones. */
	while ((xdp_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) {
		struct page *sent_page = virt_to_head_page(xdp_sent);

		put_page(sent_page);
	}

	xdp->data -= vi->hdr_len;
	/* Zero header and leave csum up to XDP layers */
	hdr = xdp->data;
	memset(hdr, 0, vi->hdr_len);

	sg_init_one(sq->sg, xdp->data, xdp->data_end - xdp->data);

	err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp->data, GFP_ATOMIC);
	if (unlikely(err)) {
		struct page *page = virt_to_head_page(xdp->data);

		put_page(page);
		return false;
	}

	virtqueue_kick(sq->vq);
	return true;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 162 77.14% 3 50.00%
Jason (Hui) Wang 41 19.52% 2 33.33%
Daniel Borkmann 7 3.33% 1 16.67%
Total 210 100.00% 6 100.00%



static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
{
	return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 21 100.00% 1 100.00%
Total 21 100.00% 1 100.00%



static struct sk_buff *receive_small(struct net_device *dev,
				     struct virtnet_info *vi,
				     struct receive_queue *rq,
				     void *buf, unsigned int len)
{
	struct sk_buff *skb;
	struct bpf_prog *xdp_prog;
	unsigned int xdp_headroom = virtnet_get_headroom(vi);
	unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
	unsigned int headroom = vi->hdr_len + header_offset;
	unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
			      SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
	unsigned int delta = 0;
	len -= vi->hdr_len;

	rcu_read_lock();
	xdp_prog = rcu_dereference(rq->xdp_prog);
	if (xdp_prog) {
		struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
		struct xdp_buff xdp;
		void *orig_data;
		u32 act;

		if (unlikely(hdr->hdr.gso_type || hdr->hdr.flags))
			goto err_xdp;

		xdp.data_hard_start = buf + VIRTNET_RX_PAD + vi->hdr_len;
		xdp.data = xdp.data_hard_start + xdp_headroom;
		xdp.data_end = xdp.data + len;
		orig_data = xdp.data;
		act = bpf_prog_run_xdp(xdp_prog, &xdp);

		switch (act) {
		case XDP_PASS:
			/* Recalculate length in case bpf program changed it */
			delta = orig_data - xdp.data;
			break;
		case XDP_TX:
			if (unlikely(!virtnet_xdp_xmit(vi, rq, &xdp)))
				trace_xdp_exception(vi->dev, xdp_prog, act);
			rcu_read_unlock();
			goto xdp_xmit;
		default:
			bpf_warn_invalid_xdp_action(act);
		case XDP_ABORTED:
			trace_xdp_exception(vi->dev, xdp_prog, act);
		case XDP_DROP:
			goto err_xdp;
		}
	}
	rcu_read_unlock();

	skb = build_skb(buf, buflen);
	if (!skb) {
		put_page(virt_to_head_page(buf));
		goto err;
	}
	skb_reserve(skb, headroom - delta);
	skb_put(skb, len + delta);
	if (!delta) {
		buf += header_offset;
		memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
	} /* keep zeroed vnet hdr since packet was changed by bpf */

err:
	return skb;

err_xdp:
	rcu_read_unlock();
	dev->stats.rx_dropped++;
	put_page(virt_to_head_page(buf));
xdp_xmit:
	return NULL;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 203 51.92% 2 25.00%
John Fastabend 156 39.90% 4 50.00%
Daniel Borkmann 28 7.16% 1 12.50%
Michael S. Tsirkin 4 1.02% 1 12.50%
Total 391 100.00% 8 100.00%



static struct sk_buff *receive_big(struct net_device *dev,
				   struct virtnet_info *vi,
				   struct receive_queue *rq,
				   void *buf,
				   unsigned int len)
{
	struct page *page = buf;
	struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);

	if (unlikely(!skb))
		goto err;

	return skb;

err:
	dev->stats.rx_dropped++;
	give_pages(rq, page);
	return NULL;
}

Contributors
Person Tokens Prop Commits CommitProp
Michael S. Tsirkin 90 98.90% 2 66.67%
Jason (Hui) Wang 1 1.10% 1 33.33%
Total 91 100.00% 3 100.00%

/* The conditions to enable XDP should preclude the underlying device from
 * sending packets across multiple buffers (num_buf > 1). However per spec
 * it does not appear to be illegal to do so but rather just against convention.
 * So in order to avoid making a system unresponsive the packets are pushed
 * into a page and the XDP program is run. This will be extremely slow and we
 * push a warning to the user to fix this as soon as possible. Fixing this may
 * require resolving the underlying hardware to determine why multiple buffers
 * are being received or simply loading the XDP program in the ingress stack
 * after the skb is built because there is no advantage to running it here
 * anymore.
 */


static struct page *xdp_linearize_page(struct receive_queue *rq,
				       u16 *num_buf,
				       struct page *p,
				       int offset,
				       unsigned int *len)
{
	struct page *page = alloc_page(GFP_ATOMIC);
	unsigned int page_off = VIRTIO_XDP_HEADROOM;

	if (!page)
		return NULL;

	memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
	page_off += *len;

	while (--*num_buf) {
		unsigned int buflen;
		unsigned long ctx;
		void *buf;
		int off;

		ctx = (unsigned long)virtqueue_get_buf(rq->vq, &buflen);
		if (unlikely(!ctx))
			goto err_buf;

		buf = mergeable_ctx_to_buf_address(ctx);
		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) > 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;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 196 87.50% 2 66.67%
Jason (Hui) Wang 28 12.50% 1 33.33%
Total 224 100.00% 3 100.00%



static struct sk_buff *receive_mergeable(struct net_device *dev,
					 struct virtnet_info *vi,
					 struct receive_queue *rq,
					 unsigned long ctx,
					 unsigned int len)
{
	void *buf = mergeable_ctx_to_buf_address(ctx);
	struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
	u16 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;
	struct bpf_prog *xdp_prog;
	unsigned int truesize;

	head_skb = NULL;

	rcu_read_lock();
	xdp_prog = rcu_dereference(rq->xdp_prog);
	if (xdp_prog) {
		struct page *xdp_page;
		struct xdp_buff xdp;
		void *data;
		u32 act;

		/* This happens when rx buffer size is underestimated */
		if (unlikely(num_buf > 1)) {
			/* linearize data for XDP */
			xdp_page = xdp_linearize_page(rq, &num_buf,
						      page, offset, &len);
			if (!xdp_page)
				goto err_xdp;
			offset = VIRTIO_XDP_HEADROOM;
		} else {
			xdp_page = page;
		}

		/* Transient failure which in theory could occur if
                 * in-flight packets from before XDP was enabled reach
                 * the receive path after XDP is loaded. In practice I
                 * was not able to create this condition.
                 */
		if (unlikely(hdr->hdr.gso_type))
			goto err_xdp;

		/* Allow consuming headroom but reserve enough space to push
                 * the descriptor on if we get an XDP_TX return code.
                 */
		data = page_address(xdp_page) + offset;
		xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len;
		xdp.data = data + vi->hdr_len;
		xdp.data_end = xdp.data + (len - vi->hdr_len);
		act = bpf_prog_run_xdp(xdp_prog, &xdp);

		switch (act) {
		case XDP_PASS:
			/* recalculate offset to account for any header
                         * adjustments. Note other cases do not build an
                         * skb and avoid using offset
                         */
			offset = xdp.data -
					page_address(xdp_page) - vi->hdr_len;

			/* We can only create skb based on xdp_page. */
			if (unlikely(xdp_page != page)) {
				rcu_read_unlock();
				put_page(page);
				head_skb = page_to_skb(vi, rq, xdp_page,
						       offset, len, PAGE_SIZE);
				ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
				return head_skb;
			}
			break;
		case XDP_TX:
			if (unlikely(!virtnet_xdp_xmit(vi, rq, &xdp)))
				trace_xdp_exception(vi->dev, xdp_prog, act);
			ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
			if (unlikely(xdp_page != page))
				goto err_xdp;
			rcu_read_unlock();
			goto xdp_xmit;
		default:
			bpf_warn_invalid_xdp_action(act);
		case XDP_ABORTED:
			trace_xdp_exception(vi->dev, xdp_prog, act);
		case XDP_DROP:
			if (unlikely(xdp_page != page))
				__free_pages(xdp_page, 0);
			ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
			goto err_xdp;
		}
	}
	rcu_read_unlock();

	truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
	head_skb = page_to_skb(vi, rq, page, offset, len, truesize);
	curr_skb = head_skb;

	if (unlikely(!curr_skb))
		goto err_skb;
	while (--num_buf) {
		int num_skb_frags;

		ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
		if (unlikely(!ctx)) {
			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.rx_length_errors++;
			goto err_buf;
		}

		buf = mergeable_ctx_to_buf_address(ctx);
		page = virt_to_head_page(buf);

		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;
		}
		truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
		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_xdp:
	rcu_read_unlock();
err_skb:
	put_page(page);
	while (--num_buf) {
		ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
		if (unlikely(!ctx)) {
			pr_debug("%s: rx error: %d buffers missing\n",
				 dev->name, num_buf);
			dev->stats.rx_length_errors++;
			break;
		}
		page = virt_to_head_page(mergeable_ctx_to_buf_address(ctx));
		put_page(page);
	}
err_buf:
	dev->stats.rx_dropped++;
	dev_kfree_skb(head_skb);
xdp_xmit:
	return NULL;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 368 42.54% 5 20.83%
Michael Dalton 169 19.54% 3 12.50%
Michael S. Tsirkin 166 19.19% 3 12.50%
Jason (Hui) Wang 111 12.83% 8 33.33%
Shirley Ma 26 3.01% 1 4.17%
Mark McLoughlin 14 1.62% 1 4.17%
Rusty Russell 10 1.16% 2 8.33%
Johannes Berg 1 0.12% 1 4.17%
Total 865 100.00% 24 100.00%



static int receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
		       void *buf, unsigned int len)
{
	struct net_device *dev = vi->dev;
	struct sk_buff *skb;
	struct virtio_net_hdr_mrg_rxbuf *hdr;
	int ret;

	if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
		pr_debug("%s: short packet %i\n", dev->name, len);
		dev->stats.rx_length_errors++;
		if (vi->mergeable_rx_bufs) {
			unsigned long ctx = (unsigned long)buf;
			void *base = mergeable_ctx_to_buf_address(ctx);
			put_page(virt_to_head_page(base));
		} else if (vi->big_packets) {
			give_pages(rq, buf);
		} else {
			put_page(virt_to_head_page(buf));
		}
		return 0;
	}

	if (vi->mergeable_rx_bufs)
		skb = receive_mergeable(dev, vi, rq, (unsigned long)buf, len);
	else if (vi->big_packets)
		skb = receive_big(dev, vi, rq, buf, len);
	else
		skb = receive_small(dev, vi, rq, buf, len);

	if (unlikely(!skb))
		return 0;

	hdr = skb_vnet_hdr(skb);

	ret = skb->len;

	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->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 ret;

frame_err:
	dev->stats.rx_frame_errors++;
	dev_kfree_skb(skb);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Shirley Ma 77 21.81% 1 4.17%
Michael Dalton 73 20.68% 3 12.50%
Mark McLoughlin 56 15.86% 1 4.17%
Jason (Hui) Wang 42 11.90% 5 20.83%
Mike Rapoport 42 11.90% 2 8.33%
Michael S. Tsirkin 29 8.22% 6 25.00%
Rusty Russell 23 6.52% 3 12.50%
Eric Dumazet 6 1.70% 1 4.17%
Pravin B Shelar 4 1.13% 1 4.17%
Américo Wang 1 0.28% 1 4.17%
Total 353 100.00% 24 100.00%



static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
			     gfp_t gfp)
{
	struct page_frag *alloc_frag = &rq->alloc_frag;
	char *buf;
	unsigned int xdp_headroom = virtnet_get_headroom(vi);
	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));
	if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
		return -ENOMEM;

	buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
	get_page(alloc_frag->page);
	alloc_frag->offset += len;
	sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
		    vi->hdr_len + GOOD_PACKET_LEN);
	err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, buf, gfp);
	if (err < 0)
		put_page(virt_to_head_page(buf));

	return err;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 88 49.44% 2 16.67%
Shirley Ma 33 18.54% 1 8.33%
Mark McLoughlin 27 15.17% 1 8.33%
John Fastabend 12 6.74% 1 8.33%
Rusty Russell 9 5.06% 4 33.33%
Michael S. Tsirkin 9 5.06% 3 25.00%
Total 178 100.00% 12 100.00%



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, MAX_SKB_FRAGS + 2);

	/* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
	for (i = MAX_SKB_FRAGS + 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, MAX_SKB_FRAGS + 2,
				  first, gfp);
	if (err < 0)
		give_pages(rq, first);

	return err;
}

Contributors
Person Tokens Prop Commits CommitProp
Shirley Ma 150 57.25% 1 9.09%
Mark McLoughlin 56 21.37% 1 9.09%
Rusty Russell 21 8.02% 5 45.45%
Jason (Hui) Wang 20 7.63% 1 9.09%
Michael S. Tsirkin 15 5.73% 3 27.27%
Total 262 100.00% 11 100.00%



static unsigned int get_mergeable_buf_len(struct ewma_pkt_len *avg_pkt_len)
{
	const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
	unsigned int len;

	len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
			GOOD_PACKET_LEN, PAGE_SIZE - hdr_len);
	return ALIGN(len, MERGEABLE_BUFFER_ALIGN);
}

Contributors
Person Tokens Prop Commits CommitProp
Michael Dalton 40 81.63% 2 40.00%
Rusty Russell 6 12.24% 1 20.00%
Johannes Berg 2 4.08% 1 20.00%
Shirley Ma 1 2.04% 1 20.00%
Total 49 100.00% 5 100.00%



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);
	char *buf;
	unsigned long ctx;
	int err;
	unsigned int len, hole;

	len = get_mergeable_buf_len(&rq->mrg_avg_pkt_len);
	if (unlikely(!skb_page_frag_refill(len + headroom, alloc_frag, gfp)))
		return -ENOMEM;

	buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
	buf += headroom; /* advance address leaving hole at front of pkt */
	ctx = mergeable_buf_to_ctx(buf, len);
	get_page(alloc_frag->page);
	alloc_frag->offset += len + headroom;
	hole = alloc_frag->size - alloc_frag->offset;
	if (hole < len + headroom) {
		/* To avoid internal fragmentation, if there is very likely not
                 * enough space for another buffer, add the remaining space to
                 * the current buffer. This extra space is not included in
                 * the truesize stored in ctx.
                 */
		len += hole;
		alloc_frag->offset += hole;
	}

	sg_init_one(rq->sg, buf, len);
	err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, (void *)ctx, gfp);
	if (err < 0)
		put_page(virt_to_head_page(buf));

	return err;
}

Contributors
Person Tokens Prop Commits CommitProp
Michael Dalton 135 63.08% 4 25.00%
Rusty Russell 28 13.08% 5 31.25%
John Fastabend 25 11.68% 1 6.25%
Shirley Ma 8 3.74% 1 6.25%
Jason (Hui) Wang 6 2.80% 1 6.25%
Herbert Xu 5 2.34% 1 6.25%
Michael S. Tsirkin 4 1.87% 2 12.50%
Mark McLoughlin 3 1.40% 1 6.25%
Total 214 100.00% 16 100.00%

/*
 * 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;

	gfp |= __GFP_COLD;
	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);
	virtqueue_kick(rq->vq);
	return !oom;
}

Contributors
Person Tokens Prop Commits CommitProp
Shirley Ma 51 45.95% 1 7.14%
Rusty Russell 23 20.72% 3 21.43%
Michael S. Tsirkin 17 15.32% 4 28.57%
Jason (Hui) Wang 8 7.21% 2 14.29%
Michael Dalton 4 3.60% 1 7.14%
Amit Shah 4 3.60% 1 7.14%
Linus Torvalds 2 1.80% 1 7.14%
John Fastabend 2 1.80% 1 7.14%
Total 111 100.00% 14 100.00%



static void skb_recv_done(struct virtqueue *rvq)
{
	struct virtnet_info *vi = rvq->vdev->priv;
	struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];

	/* Schedule NAPI, Suppress further interrupts if successful. */
	if (napi_schedule_prep(&rq->napi)) {
		virtqueue_disable_cb(rvq);
		__napi_schedule(&rq->napi);
	}
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 43 67.19% 2 33.33%
Jason (Hui) Wang 18 28.12% 2 33.33%
Ben Hutchings 2 3.12% 1 16.67%
Michael S. Tsirkin 1 1.56% 1 16.67%
Total 64 100.00% 6 100.00%



static void virtnet_napi_enable(struct receive_queue *rq)
{
	napi_enable(&rq->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.  virtnet_poll wants re-enable the queue, so we disable here.
         * We synchronize against interrupts via NAPI_STATE_SCHED */
	if (napi_schedule_prep(&rq->napi)) {
		virtqueue_disable_cb(rq->vq);
		local_bh_disable();
		__napi_schedule(&rq->napi);
		local_bh_enable();
	}
}

Contributors
Person Tokens Prop Commits CommitProp
Bruce Rogers 40 75.47% 1 33.33%
Jason (Hui) Wang 7 13.21% 1 33.33%
Michael S. Tsirkin 6 11.32% 1 33.33%
Total 53 100.00% 3 100.00%



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);

		/* 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);
	}
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 56 52.83% 1 12.50%
Jason (Hui) Wang 42 39.62% 2 25.00%
Herbert Xu 3 2.83% 1 12.50%
Michael S. Tsirkin 2 1.89% 1 12.50%
Tejun Heo 1 0.94% 1 12.50%
Bruce Rogers 1 0.94% 1 12.50%
Sasha Levin 1 0.94% 1 12.50%
Total 106 100.00% 8 100.00%



static int virtnet_receive(struct receive_queue *rq, int budget)
{
	struct virtnet_info *vi = rq->vq->vdev->priv;
	unsigned int len, received = 0, bytes = 0;
	void *buf;
	struct virtnet_stats *stats = this_cpu_ptr(vi->stats);

	while (received < budget &&
	       (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
		bytes += receive_buf(vi, rq, buf, len);
		received++;
	}

	if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
		if (!try_fill_recv(vi, rq, GFP_ATOMIC))
			schedule_delayed_work(&vi->refill, 0);
	}

	u64_stats_update_begin(&stats->rx_syncp);
	stats->rx_bytes += bytes;
	stats->rx_packets += received;
	u64_stats_update_end(&stats->rx_syncp);

	return received;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 83 49.70% 4 40.00%
Rusty Russell 75 44.91% 2 20.00%
Michael S. Tsirkin 5 2.99% 2 20.00%
Shirley Ma 3 1.80% 1 10.00%
Tejun Heo 1 0.60% 1 10.00%
Total 167 100.00% 10 100.00%



static int virtnet_poll(struct napi_struct *napi, int budget)
{
	struct receive_queue *rq =
		container_of(napi, struct receive_queue, napi);
	unsigned int r, received;

	received = virtnet_receive(rq, budget);

	/* Out of packets? */
	if (received < budget) {
		r = virtqueue_enable_cb_prepare(rq->vq);
		if (napi_complete_done(napi, received)) {
			if (unlikely(virtqueue_poll(rq->vq, r)) &&
			    napi_schedule_prep(napi)) {
				virtqueue_disable_cb(rq->vq);
				__napi_schedule(napi);
			}
		}
	}

	return received;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 46 42.20% 2 18.18%
Rusty Russell 28 25.69% 2 18.18%
Michael S. Tsirkin 13 11.93% 2 18.18%
Christian Bornträger 12 11.01% 1 9.09%
Eric Dumazet 8 7.34% 2 18.18%
Ben Hutchings 1 0.92% 1 9.09%
Li RongQing 1 0.92% 1 9.09%
Total 109 100.00% 11 100.00%



static int virtnet_open(struct net_device *dev)
{
	struct virtnet_info *vi = netdev_priv(dev);
	int i;

	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);
		virtnet_napi_enable(&vi->rq[i]);
	}

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 90 97.83% 2 66.67%
Michael S. Tsirkin 2 2.17% 1 33.33%
Total 92 100.00% 3 100.00%



static void free_old_xmit_skbs(struct send_queue *sq)
{
	struct sk_buff *skb;
	unsigned int len;
	struct virtnet_info *vi = sq->vq->vdev->priv;
	struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
	unsigned int packets = 0;
	unsigned int bytes = 0;

	while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
		pr_debug("Sent skb %p\n", skb);

		bytes += skb->len;
		packets++;

		dev_kfree_skb_any(skb);
	}

	/* Avoid overhead when no packets have been processed
         * happens when called speculatively from start_xmit.
         */
	if (!packets)
		return;

	u64_stats_update_begin(&stats->tx_syncp);
	stats->tx_bytes += bytes;
	stats->tx_packets += packets;
	u64_stats_update_end(&stats->tx_syncp);
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 54 40.60% 2 28.57%
Rusty Russell 48 36.09% 1 14.29%
Stephen Hemminger 27 20.30% 1 14.29%
Eric Dumazet 2 1.50% 1 14.29%
Linus Torvalds 1 0.75% 1 14.29%
Michael S. Tsirkin 1 0.75% 1 14.29%
Total 133 100.00% 7 100.00%



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;
	unsigned 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_hdr(skb);

	if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
				    virtio_is_little_endian(vi->vdev), false))
		BUG();

	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);
		/* 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) + 1;
	}
	return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
}

Contributors
Person Tokens Prop Commits CommitProp
Michael S. Tsirkin 128 42.95% 5 22.73%
Rusty Russell 108 36.24% 9 40.91%
Jason (Hui) Wang 39 13.09% 3 13.64%
Mark McLoughlin 17 5.70% 1 4.55%
Mike Rapoport 3 1.01% 1 4.55%
Johannes Berg 1 0.34% 1 4.55%
Ira W. Snyder 1 0.34% 1 4.55%
David S. Miller 1 0.34% 1 4.55%
Total 298 100.00% 22 100.00%



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 = !skb->xmit_more;

	/* Free up any pending old buffers before queueing new ones. */
	free_old_xmit_skbs(sq);

	/* 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.tx_fifo_errors++;
		if (net_ratelimit())
			dev_warn(&dev->dev,
				 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
		dev->stats.tx_dropped++;
		dev_kfree_skb_any(skb);
		return NETDEV_TX_OK;
	}

	/* Don't wait up for transmitted skbs to be freed. */
	skb_orphan(skb);
	nf_reset(skb);

	/* 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 (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
			/* More just got used, free them then recheck. */
			free_old_xmit_skbs(sq);
			if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
				netif_start_subqueue(dev, qnum);
				virtqueue_disable_cb(sq->vq);
			}
		}
	}

	if (kick || netif_xmit_stopped(txq))
		virtqueue_kick(sq->vq);

	return NETDEV_TX_OK;
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 141 57.79% 8 32.00%
Jason (Hui) Wang 36 14.75% 2 8.00%
Michael S. Tsirkin 31 12.70% 6 24.00%
David S. Miller 16 6.56% 3 12.00%
Jacob E Keller 6 2.46% 1 4.00%
Rick Jones 5 2.05% 1 4.00%
Linus Torvalds 5 2.05% 1 4.00%
Christian Bornträger 2 0.82% 1 4.00%
Stephen Hemminger 1 0.41% 1 4.00%
Eric W. Biedermann 1 0.41% 1 4.00%
Total 244 100.00% 25 100.00%

/*
 * 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;

	/* 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));
	virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);

	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;
}

Contributors
Person Tokens Prop Commits CommitProp
Amos Kong 120 53.10% 1 16.67%
Rusty Russell 54 23.89% 1 16.67%
Michael S. Tsirkin 31 13.72% 1 16.67%
Heinz Graalfs 19 8.41% 2 33.33%
Stephen Hemminger 2 0.88% 1 16.67%
Total 226 100.00% 6 100.00%



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;

	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;
}

Contributors
Person Tokens Prop Commits CommitProp
Amos Kong 76 33.19% 1 11.11%
Alex Williamson 60 26.20% 2 22.22%
Andrew Lutomirski 43 18.78% 1 11.11%
Rusty Russell 25 10.92% 1 11.11%
Jiri Pirko 14 6.11% 2 22.22%
Michael S. Tsirkin 8 3.49% 1 11.11%
Shyam Saini 3 1.31% 1 11.11%
Total 229 100.00% 9 100.00%



static void virtnet_stats(struct net_device *dev,
			  struct rtnl_link_stats64 *tot)
{
	struct virtnet_info *vi = netdev_priv(dev);
	int cpu;
	unsigned int start;

	for_each_possible_cpu(cpu) {
		struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
		u64 tpackets, tbytes, rpackets, rbytes;

		do {
			start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
			tpackets = stats->tx_packets;
			tbytes   = stats->tx_bytes;
		} while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));

		do {
			start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
			rpackets = stats->rx_packets;
			rbytes   = stats->rx_bytes;
		} while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));

		tot->rx_packets += rpackets;
		tot->tx_packets += tpackets;
		tot->rx_bytes   += rbytes;
		tot->tx_bytes   += tbytes;
	}

	tot->tx_dropped = dev->stats.tx_dropped;
	tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
	tot->rx_dropped = dev->stats.rx_dropped;
	tot->rx_length_errors = dev->stats.rx_length_errors;
	tot->rx_frame_errors = dev->stats.rx_frame_errors;
}

Contributors
Person Tokens Prop Commits CommitProp
Stephen Hemminger 172 81.13% 2 40.00%
Eric Dumazet 26 12.26% 1 20.00%
Rick Jones 10 4.72% 1 20.00%
Eric W. Biedermann 4 1.89% 1 20.00%
Total 212 100.00% 5 100.00%

#ifdef CONFIG_NET_POLL_CONTROLLER


static void virtnet_netpoll(struct net_device *dev)
{
	struct virtnet_info *vi = netdev_priv(dev);
	int i;

	for (i = 0; i < vi->curr_queue_pairs; i++)
		napi_schedule(&vi->rq[i].napi);
}
Contributors
Person Tokens Prop Commits CommitProp
Amit Shah 29 55.77% 1 33.33%
Jason (Hui) Wang 23 44.23% 2 66.67%
Total 52 100.00% 3 100.00%

#endif



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();
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 43 100.00% 1 100.00%
Total 43 100.00% 1 100.00%



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;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 111 77.08% 3 42.86%
Sasha Levin 16 11.11% 1 14.29%
Andrew Lutomirski 9 6.25% 1 14.29%
Michael S. Tsirkin 7 4.86% 1 14.29%
John Fastabend 1 0.69% 1 14.29%
Total 144 100.00% 7 100.00%



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;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 35 100.00% 1 100.00%
Total 35 100.00% 1 100.00%



static int virtnet_close(struct net_device *dev)
{
	struct virtnet_info *vi = netdev_priv(dev);
	int i;

	/* Make sure refill_work doesn't re-enable napi! */
	cancel_delayed_work_sync(&vi->refill);

	for (i = 0; i < vi->max_queue_pairs; i++)
		napi_disable(&vi->rq[i].napi);

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 41 64.06% 2 50.00%
Jason (Hui) Wang 23 35.94% 2 50.00%
Total 64 100.00% 4 100.00%



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);
}

Contributors
Person Tokens Prop Commits CommitProp
Alex Williamson 347 79.04% 3 25.00%
Jiri Pirko 52 11.85% 5 41.67%
Michael S. Tsirkin 38 8.66% 2 16.67%
Stephen Hemminger 1 0.23% 1 8.33%
Thomas Huth 1 0.23% 1 8.33%
Total 439 100.00% 12 100.00%



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 = 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;
}

Contributors
Person Tokens Prop Commits CommitProp
Alex Williamson 66 77.65% 3 50.00%
Andrew Lutomirski 12 14.12% 1 16.67%
Jiri Pirko 4 4.71% 1 16.67%
Patrick McHardy 3 3.53% 1 16.67%
Total 85 100.00% 6 100.00%



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 = 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;
}

Contributors
Person Tokens Prop Commits CommitProp
Alex Williamson 66 77.65% 3 50.00%
Andrew Lutomirski 12 14.12% 1 16.67%
Jiri Pirko 4 4.71% 1 16.67%
Patrick McHardy 3 3.53% 1 16.67%
Total 85 100.00% 6 100.00%



static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
{
	int i;

	if (vi->affinity_hint_set) {
		for (i = 0; i < vi->max_queue_pairs; i++) {
			virtqueue_set_affinity(vi->rq[i].vq, -1);
			virtqueue_set_affinity(vi->sq[i].vq, -1);
		}

		vi->affinity_hint_set = false;
	}
}

Contributors
Person Tokens Prop Commits CommitProp
Wanlong Gao 42 53.85% 2 50.00%
Jason (Hui) Wang 26 33.33% 1 25.00%
Rick Jones 10 12.82% 1 25.00%
Total 78 100.00% 4 100.00%



static void virtnet_set_affinity(struct virtnet_info *vi)
{
	int i;
	int cpu;

	/* In multiqueue mode, when the number of cpu is equal to the number of
         * queue pairs, we let the queue pairs to be private to one cpu by
         * setting the affinity hint to eliminate the contention.
         */
	if (vi->curr_queue_pairs == 1 ||
	    vi->max_queue_pairs != num_online_cpus()) {
		virtnet_clean_affinity(vi, -1);
		return;
	}

	i = 0;
	for_each_online_cpu(cpu) {
		virtqueue_set_affinity(vi->rq[i].vq, cpu);
		virtqueue_set_affinity(vi->sq[i].vq, cpu);
		netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
		i++;
	}

	vi->affinity_hint_set = true;
}

Contributors
Person Tokens Prop Commits CommitProp
Wanlong Gao 55 52.38% 2 50.00%
Jason (Hui) Wang 50 47.62% 2 50.00%
Total 105 100.00% 4 100.00%



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;
}

Contributors
Person Tokens Prop Commits CommitProp
Sebastian Andrzej Siewior 33 86.84% 1 50.00%
Wanlong Gao 5 13.16% 1 50.00%
Total 38 100.00% 2 100.00%



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;
}

Contributors
Person Tokens Prop Commits CommitProp
Wanlong Gao 22 57.89% 1 50.00%
Sebastian Andrzej Siewior 16 42.11% 1 50.00%
Total 38 100.00% 2 100.00%



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, cpu);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Sebastian Andrzej Siewior 33 82.50% 1 50.00%
Wanlong Gao 7 17.50% 1 50.00%
Total 40 100.00% 2 100.00%


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;
}

Contributors
Person Tokens Prop Commits CommitProp
Sebastian Andrzej Siewior 64 96.97% 1 50.00%
Wanlong Gao 2 3.03% 1 50.00%
Total 66 100.00% 2 100.00%



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);
}

Contributors
Person Tokens Prop Commits CommitProp
Sebastian Andrzej Siewior 30 96.77% 1 50.00%
Wanlong Gao 1 3.23% 1 50.00%
Total 31 100.00% 2 100.00%



static void virtnet_get_ringparam(struct net_device *dev,
				struct ethtool_ringparam *ring)
{
	struct virtnet_info *vi = netdev_priv(dev);

	ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
	ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
	ring->rx_pending = ring->rx_max_pending;
	ring->tx_pending = ring->tx_max_pending;
}


Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 63 85.14% 1 50.00%
Rick Jones 11 14.86% 1 50.00%
Total 74 100.00% 2 100.00%



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;

	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
	strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
	strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));

}

Contributors
Person Tokens Prop Commits CommitProp
Rick Jones 86 100.00% 1 100.00%
Total 86 100.00% 1 100.00%

/* 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;

	get_online_cpus();
	err = _virtnet_set_queues(vi, queue_pairs);
	if (!err) {
		netif_set_real_num_tx_queues(dev, queue_pairs);
		netif_set_real_num_rx_queues(dev, queue_pairs);

		virtnet_set_affinity(vi);
	}
	put_online_cpus();

	return err;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 104 79.39% 1 20.00%
John Fastabend 17 12.98% 2 40.00%
Wanlong Gao 6 4.58% 1 20.00%
Amos Kong 4 3.05% 1 20.00%
Total 131 100.00% 5 100.00%



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;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 66 100.00% 1 100.00%
Total 66 100.00% 1 100.00%

/* Check if the user is trying to change anything besides speed/duplex */


static bool virtnet_validate_ethtool_cmd(const struct ethtool_cmd *cmd)
{
	struct ethtool_cmd diff1 = *cmd;
	struct ethtool_cmd diff2 = {};

	/* cmd is always set so we need to clear it, validate the port type
         * and also without autonegotiation we can ignore advertising
         */
	ethtool_cmd_speed_set(&diff1, 0);
	diff2.port = PORT_OTHER;
	diff1.advertising = 0;
	diff1.duplex = 0;
	diff1.cmd = 0;

	return !memcmp(&diff1, &diff2, sizeof(diff1));
}

Contributors
Person Tokens Prop Commits CommitProp
Nikolay Aleksandrov 74 100.00% 2 100.00%
Total 74 100.00% 2 100.00%



static int virtnet_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
	struct virtnet_info *vi = netdev_priv(dev);
	u32 speed;

	speed = ethtool_cmd_speed(cmd);
	/* don't allow custom speed and duplex */
	if (!ethtool_validate_speed(speed) ||
	    !ethtool_validate_duplex(cmd->duplex) ||
	    !virtnet_validate_ethtool_cmd(cmd))
		return -EINVAL;
	vi->speed = speed;
	vi->duplex = cmd->duplex;

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Nikolay Aleksandrov 80 100.00% 1 100.00%
Total 80 100.00% 1 100.00%



static int virtnet_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
	struct virtnet_info *vi = netdev_priv(dev);

	ethtool_cmd_speed_set(cmd, vi->speed);
	cmd->duplex = vi->duplex;
	cmd->port = PORT_OTHER;

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Nikolay Aleksandrov 52 100.00% 1 100.00%
Total 52 100.00% 1 100.00%



static void virtnet_init_settings(struct net_device *dev)
{
	struct virtnet_info *vi = netdev_priv(dev);

	vi->speed = SPEED_UNKNOWN;
	vi->duplex = DUPLEX_UNKNOWN;
}

Contributors
Person Tokens Prop Commits CommitProp
Nikolay Aleksandrov 33 100.00% 1 100.00%
Total 33 100.00% 1 100.00%


static const struct ethtool_ops virtnet_ethtool_ops = {
	.get_drvinfo = virtnet_get_drvinfo,
	.get_link = ethtool_op_get_link,
	.get_ringparam = virtnet_get_ringparam,
	.set_channels = virtnet_set_channels,
	.get_channels = virtnet_get_channels,
	.get_ts_info = ethtool_op_get_ts_info,
	.get_settings = virtnet_get_settings,
	.set_settings = virtnet_set_settings,
};



static void virtnet_freeze_down(struct virtio_device *vdev)
{
	struct virtnet_info *vi = vdev->priv;
	int i;

	/* Make sure no work handler is accessing the device */
	flush_work(&vi->config_work);

	netif_device_detach(vi->dev);
	cancel_delayed_work_sync(&vi->refill);

	if (netif_running(vi->dev)) {
		for (i = 0; i < vi->max_queue_pairs; i++)
			napi_disable(&vi->rq[i].napi);
	}
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 86 100.00% 1 100.00%
Total 86 100.00% 1 100.00%

static int init_vqs(struct virtnet_info *vi);
static void _remove_vq_common(struct virtnet_info *vi);



static int virtnet_restore_up(struct virtio_device *vdev)
{
	struct virtnet_info *vi = vdev->priv;
	int err, i;

	err = init_vqs(vi);
	if (err)
		return err;

	virtio_device_ready(vdev);

	if (netif_running(vi->dev)) {
		for (i = 0; i < vi->curr_queue_pairs; i++)
			if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
				schedule_delayed_work(&vi->refill, 0);

		for (i = 0; i < vi->max_queue_pairs; i++)
			virtnet_napi_enable(&vi->rq[i]);
	}

	netif_device_attach(vi->dev);
	return err;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 134 100.00% 1 100.00%
Total 134 100.00% 1 100.00%



static int virtnet_reset(struct virtnet_info *vi, int curr_qp, int xdp_qp)
{
	struct virtio_device *dev = vi->vdev;
	int ret;

	virtio_config_disable(dev);
	dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
	virtnet_freeze_down(dev);
	_remove_vq_common(vi);

	dev->config->reset(dev);
	virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
	virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER);

	ret = virtio_finalize_features(dev);
	if (ret)
		goto err;

	vi->xdp_queue_pairs = xdp_qp;
	ret = virtnet_restore_up(dev);
	if (ret)
		goto err;
	ret = _virtnet_set_queues(vi, curr_qp);
	if (ret)
		goto err;

	virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
	virtio_config_enable(dev);
	return 0;
err:
	virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
	return ret;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 146 91.82% 1 50.00%
Jason (Hui) Wang 13 8.18% 1 50.00%
Total 159 100.00% 2 100.00%



static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog)
{
	unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
	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_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)) {
		netdev_warn(dev, "can't set XDP while host is implementing LRO, disable LRO first\n");
		return -EOPNOTSUPP;
	}

	if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
		netdev_warn(dev, "XDP expects header/data in single page, any_header_sg required\n");
		return -EINVAL;
	}

	if (dev->mtu > max_sz) {
		netdev_warn(dev, "XDP requires MTU less than %lu\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(dev, "request %i queues but max is %i\n",
			    curr_qp + xdp_qp, vi->max_queue_pairs);
		return -ENOMEM;
	}

	if (prog) {
		prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
		if (IS_ERR(prog))
			return PTR_ERR(prog);
	}

	/* Changing the headroom in buffers is a disruptive operation because
         * existing buffers must be flushed and reallocated. This will happen
         * when a xdp program is initially added or xdp is disabled by removing
         * the xdp program resulting in number of XDP queues changing.
         */
	if (vi->xdp_queue_pairs != xdp_qp) {
		err = virtnet_reset(vi, curr_qp + xdp_qp, xdp_qp);
		if (err) {
			dev_warn(&dev->dev, "XDP reset failure.\n");
			goto virtio_reset_err;
		}
	}

	netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);

	for (i = 0; i < vi->max_queue_pairs; i++) {
		old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
		rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
		if (old_prog)
			bpf_prog_put(old_prog);
	}

	return 0;

virtio_reset_err:
	/* On reset error do our best to unwind XDP changes inflight and return
         * error up to user space for resolution. The underlying reset hung on
         * us so not much we can do here.
         */
	if (prog)
		bpf_prog_sub(prog, vi->max_queue_pairs - 1);
	return err;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 333 90.98% 3 60.00%
Jason (Hui) Wang 33 9.02% 2 40.00%
Total 366 100.00% 5 100.00%



static bool virtnet_xdp_query(struct net_device *dev)
{
	struct virtnet_info *vi = netdev_priv(dev);
	int i;

	for (i = 0; i < vi->max_queue_pairs; i++) {
		if (vi->rq[i].xdp_prog)
			return true;
	}
	return false;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 58 100.00% 1 100.00%
Total 58 100.00% 1 100.00%



static int virtnet_xdp(struct net_device *dev, struct netdev_xdp *xdp)
{
	switch (xdp->command) {
	case XDP_SETUP_PROG:
		return virtnet_xdp_set(dev, xdp->prog);
	case XDP_QUERY_PROG:
		xdp->prog_attached = virtnet_xdp_query(dev);
		return 0;
	default:
		return -EINVAL;
	}
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 57 100.00% 1 100.00%
Total 57 100.00% 1 100.00%


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,
#ifdef CONFIG_NET_POLL_CONTROLLER
	.ndo_poll_controller = virtnet_netpoll,
#endif
	.ndo_xdp		= virtnet_xdp,
};



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) {
		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);
	}
}

Contributors
Person Tokens Prop Commits CommitProp
Mark McLoughlin 86 65.15% 1 14.29%
Jason (Hui) Wang 39 29.55% 2 28.57%
Sasha Levin 3 2.27% 1 14.29%
Michael S. Tsirkin 2 1.52% 1 14.29%
Rusty Russell 1 0.76% 1 14.29%
Américo Wang 1 0.76% 1 14.29%
Total 132 100.00% 7 100.00%



static void virtnet_config_changed(struct virtio_device *vdev)
{
	struct virtnet_info *vi = vdev->priv;

	schedule_work(&vi->config_work);
}

Contributors
Person Tokens Prop Commits CommitProp
Mark McLoughlin 24 85.71% 1 33.33%
Jason (Hui) Wang 3 10.71% 1 33.33%
Tejun Heo 1 3.57% 1 33.33%
Total 28 100.00% 3 100.00%



static void virtnet_free_queues(struct virtnet_info *vi)
{
	int i;

	for (i = 0; i < vi->max_queue_pairs; i++) {
		napi_hash_del(&vi->rq[i].napi);
		netif_napi_del(&vi->rq[i].napi);
	}

	/* We called napi_hash_del() before netif_napi_del(),
         * we need to respect an RCU grace period before freeing vi->rq
         */
	synchronize_net();

	kfree(vi->rq);
	kfree(vi->sq);
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 40 53.33% 3 60.00%
Andrey Vagin 31 41.33% 1 20.00%
Eric Dumazet 4 5.33% 1 20.00%
Total 75 100.00% 5 100.00%



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);
	}
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 47 46.08% 1 16.67%
John Fastabend 44 43.14% 2 33.33%
Rusty Russell 6 5.88% 1 16.67%
Amit Shah 4 3.92% 1 16.67%
Michael S. Tsirkin 1 0.98% 1 16.67%
Total 102 100.00% 6 100.00%



static void free_receive_bufs(struct virtnet_info *vi)
{
	rtnl_lock();
	_free_receive_bufs(vi);
	rtnl_unlock();
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 21 95.45% 2 66.67%
Jason (Hui) Wang 1 4.55% 1 33.33%
Total 22 100.00% 3 100.00%



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)
			put_page(vi->rq[i].alloc_frag.page);
}

Contributors
Person Tokens Prop Commits CommitProp
Michael Dalton 56 100.00% 1 100.00%
Total 56 100.00% 1 100.00%



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;
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 47 100.00% 2 100.00%
Total 47 100.00% 2 100.00%



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) {
			if (!is_xdp_raw_buffer_queue(vi, i))
				dev_kfree_skb(buf);
			else
				put_page(virt_to_head_page(buf));
		}
	}

	for (i = 0; i < vi->max_queue_pairs; i++) {
		struct virtqueue *vq = vi->rq[i].vq;

		while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
			if (vi->mergeable_rx_bufs) {
				unsigned long ctx = (unsigned long)buf;
				void *base = mergeable_ctx_to_buf_address(ctx);
				put_page(virt_to_head_page(base));
			} else if (vi->big_packets) {
				give_pages(&vi->rq[i], buf);
			} else {
				put_page(virt_to_head_page(buf));
			}
		}
	}
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 130 64.36% 2 28.57%
Michael Dalton 36 17.82% 2 28.57%
John Fastabend 21 10.40% 2 28.57%
Andrey Vagin 15 7.43% 1 14.29%
Total 202 100.00% 7 100.00%



static void virtnet_del_vqs(struct virtnet_info *vi)
{
	struct virtio_device *vdev = vi->vdev;

	virtnet_clean_affinity(vi, -1);

	vdev->config->del_vqs(vdev);

	virtnet_free_queues(vi);
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 39 92.86% 1 50.00%
Wanlong Gao 3 7.14% 1 50.00%
Total 42 100.00% 2 100.00%



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;

	/* 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 = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
	if (!vqs)
		goto err_vq;
	callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
	if (!callbacks)
		goto err_callback;
	names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
	if (!names)
		goto err_names;

	/* 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;
	}

	ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
					 names, 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->sq[i].vq = vqs[txq2vq(i)];
	}

	kfree(names);
	kfree(callbacks);
	kfree(vqs);

	return 0;

err_find:
	kfree(names);
err_names:
	kfree(callbacks);
err_callback:
	kfree(vqs);
err_vq:
	return ret;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 402 95.04% 1 25.00%
Amit Shah 18 4.26% 1 25.00%
Christoph Hellwig 2 0.47% 1 25.00%
Patrick McHardy 1 0.24% 1 25.00%
Total 423 100.00% 4 100.00%



static int virtnet_alloc_queues(struct virtnet_info *vi)
{
	int i;

	vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
	if (!vi->sq)
		goto err_sq;
	vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, 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(vi->dev, &vi->rq[i].napi, virtnet_poll,
			       napi_weight);

		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));
	}

	return 0;

err_rq:
	kfree(vi->sq);
err_sq:
	return -ENOMEM;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 182 85.05% 2 33.33%
Amit Shah 18 8.41% 1 16.67%
Michael Dalton 12 5.61% 1 16.67%
Johannes Berg 1 0.47% 1 16.67%
Américo Wang 1 0.47% 1 16.67%
Total 214 100.00% 6 100.00%



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;

	get_online_cpus();
	virtnet_set_affinity(vi);
	put_online_cpus();

	return 0;

err_free:
	virtnet_free_queues(vi);
err:
	return ret;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 48 69.57% 1 33.33%
Amit Shah 15 21.74% 1 33.33%
Wanlong Gao 6 8.70% 1 33.33%
Total 69 100.00% 3 100.00%

#ifdef CONFIG_SYSFS


static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
		struct rx_queue_attribute *attribute, char *buf)
{
	struct virtnet_info *vi = netdev_priv(queue->dev);
	unsigned int queue_index = get_netdev_rx_queue_index(queue);
	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(avg));
}

Contributors
Person Tokens Prop Commits CommitProp
Michael Dalton 79 98.75% 1 50.00%
Johannes Berg 1 1.25% 1 50.00%
Total 80 100.00% 2 100.00%


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;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 55 100.00% 1 100.00%
Total 55 100.00% 1 100.00%


#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"))) {
		return false;
	}

	return true;
}

Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 76 100.00% 1 100.00%
Total 76 100.00% 1 100.00%


#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);
	}

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Michael S. Tsirkin 72 77.42% 2 50.00%
Jason (Hui) Wang 12 12.90% 1 25.00%
Amit Shah 9 9.68% 1 25.00%
Total 93 100.00% 4 100.00%



static int virtnet_probe(struct virtio_device *vdev)
{
	int i, err;
	struct net_device *dev;
	struct virtnet_info *vi;
	u16 max_queue_pairs;
	int mtu;

	/* Find if host supports multiqueue virtio_net device */
	err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
				   struct virtio_net_config,
				   max_virtqueue_pairs, &max_queue_pairs);

	/* We need at least 2 queue's */
	if (err || 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;
	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_UFO
				| 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_UFO))
			dev->hw_features |= NETIF_F_UFO;

		dev->features |= NETIF_F_GSO_ROBUST;

		if (gso)
			dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
		/* (!csum && gso) case will be fixed by register_netdev() */
	}
	if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
		dev->features |= NETIF_F_RXCSUM;

	dev->vlan_features = dev->features;

	/* 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))
		virtio_cread_bytes(vdev,
				   offsetof(struct virtio_net_config, mac),
				   dev->dev_addr, dev->addr_len);
	else
		eth_hw_addr_random(dev);

	/* Set up our device-specific information */
	vi = netdev_priv(dev);
	vi->dev = dev;
	vi->vdev = vdev;
	vdev->priv = vi;
	vi->stats = alloc_percpu(struct virtnet_stats);
	err = -ENOMEM;
	if (vi->stats == NULL)
		goto free;

	for_each_possible_cpu(i) {
		struct virtnet_stats *virtnet_stats;
		virtnet_stats = per_cpu_ptr(vi->stats, i);
		u64_stats_init(&virtnet_stats->tx_syncp);
		u64_stats_init(&virtnet_stats->rx_syncp);
	}

	INIT_WORK(&vi->config_work, virtnet_config_changed_work);

	/* If we can receive ANY GSO packets, we must allocate large ones. */
	if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
	    virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
	    virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
	    virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
		vi->big_packets = true;

	if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
		vi->mergeable_rx_bufs = true;

	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);
			goto free_stats;
		}

		dev->mtu = mtu;
		dev->max_mtu = mtu;

		/* TODO: size buffers correctly in this case. */
		if (dev->mtu > ETH_DATA_LEN)
			vi->big_packets = true;
	}

	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_stats;

#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);

	err = register_netdev(dev);
	if (err) {
		pr_debug("virtio_net: registering device failed\n");
		goto free_vqs;
	}

	virtio_device_ready(vdev);

	err = virtnet_cpu_notif_add(vi);
	if (err) {
		pr_debug("virtio_net: registering cpu notifier failed\n");
		goto free_unregister_netdev;
	}

	virtnet_set_queues(vi, vi->curr_queue_pairs);

	/* Assume link up if device can't report link status,
           otherwise get link status from config. */
	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
		netif_carrier_off(dev);
		schedule_work(&vi->config_work);
	} else {
		vi->status = VIRTIO_NET_S_LINK_UP;
		netif_carrier_on(dev);
	}

	pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
		 dev->name, max_queue_pairs);

	return 0;

free_unregister_netdev:
	vi->vdev->config->reset(vdev);

	unregister_netdev(dev);
free_vqs:
	cancel_delayed_work_sync(&vi->refill);
	free_receive_page_frags(vi);
	virtnet_del_vqs(vi);
free_stats:
	free_percpu(vi->stats);
free:
	free_netdev(dev);
	return err;
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 249 26.83% 8 14.04%
Jason (Hui) Wang 175 18.86% 9 15.79%
Michael S. Tsirkin 143 15.41% 9 15.79%
Aaron Conole 43 4.63% 2 3.51%
John Stultz 38 4.09% 1 1.75%
Stephen Hemminger 36 3.88% 2 3.51%
Herbert Xu 34 3.66% 2 3.51%
Vlad Yasevich 26 2.80% 1 1.75%
Michał Mirosław 26 2.80% 1 1.75%
Mark McLoughlin 25 2.69% 3 5.26%
Michael Dalton 24 2.59% 3 5.26%
Jarod Wilson 23 2.48% 1 1.75%
Wanlong Gao 19 2.05% 1 1.75%
Thomas Huth 15 1.62% 1 1.75%
Zhangjie \(HZ\) 12 1.29% 1 1.75%
Jiri Pirko 8 0.86% 2 3.51%
Christian Bornträger 6 0.65% 1 1.75%
Zhi Yong Wu 6 0.65% 1 1.75%
Pantelis Koukousoulas 5 0.54% 1 1.75%
Nikolay Aleksandrov 5 0.54% 1 1.75%
Wilfried Klaebe 3 0.32% 1 1.75%
wangyunjian 2 0.22% 1 1.75%
Amit Shah 2 0.22% 1 1.75%
Tejun Heo 1 0.11% 1 1.75%
Sebastian Andrzej Siewior 1 0.11% 1 1.75%
Danny Kukawka 1 0.11% 1 1.75%
Total 928 100.00% 57 100.00%



static void _remove_vq_common(struct virtnet_info *vi)
{
	vi->vdev->config->reset(vi->vdev);
	free_unused_bufs(vi);
	_free_receive_bufs(vi);
	free_receive_page_frags(vi);
	virtnet_del_vqs(vi);
}

Contributors
Person Tokens Prop Commits CommitProp
John Fastabend 44 100.00% 1 100.00%
Total 44 100.00% 1 100.00%



static void remove_vq_common(struct virtnet_info *vi)
{
	vi->vdev->config->reset(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);
}

Contributors
Person Tokens Prop Commits CommitProp
Rusty Russell 27 60.00% 5 50.00%
Shirley Ma 6 13.33% 2 20.00%
Michael Dalton 5 11.11% 1 10.00%
Amit Shah 5 11.11% 1 10.00%
Jason (Hui) Wang 2 4.44% 1 10.00%
Total 45 100.00% 10 100.00%



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);

	remove_vq_common(vi);

	free_percpu(vi->stats);
	free_netdev(vi->dev);
}

Contributors
Person Tokens Prop Commits CommitProp
Amit Shah 31 51.67% 1 12.50%
Rusty Russell 8 13.33% 2 25.00%
Krishna Kumar 7 11.67% 1 12.50%
Jason (Hui) Wang 6 10.00% 1 12.50%
Wanlong Gao 4 6.67% 1 12.50%
Michael S. Tsirkin 3 5.00% 1 12.50%
Sebastian Andrzej Siewior 1 1.67% 1 12.50%
Total 60 100.00% 8 100.00%

#ifdef CONFIG_PM_SLEEP


static 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;
}

Contributors
Person Tokens Prop Commits CommitProp
Amit Shah 29 76.32% 1 20.00%
Jason (Hui) Wang 6 15.79% 2 40.00%
John Fastabend 2 5.26% 1 20.00%
Sebastian Andrzej Siewior 1 2.63% 1 20.00%
Total 38 100.00% 5 100.00%



static 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)
		return err;

	return 0;
}
Contributors
Person Tokens Prop Commits CommitProp
Amit Shah 38 60.32% 1 20.00%
Jason (Hui) Wang 22 34.92% 2 40.00%
John Fastabend 2 3.17% 1 20.00%
Sebastian Andrzej Siewior 1 1.59% 1 20.00%
Total 63 100.00% 5 100.00%

#endif


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_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


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;
}
Contributors
Person Tokens Prop Commits CommitProp
Sebastian Andrzej Siewior 93 97.89% 1 50.00%
Thomas Gleixner 2 2.11% 1 50.00%
Total 95 100.00% 2 100.00%


module_init(virtio_net_driver_init);



static __exit void virtio_net_driver_exit(void)
{
	cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
	cpuhp_remove_multi_state(virtionet_online);
	unregister_virtio_driver(&virtio_net_driver);
}
Contributors
Person Tokens Prop Commits CommitProp
Sebastian Andrzej Siewior 22 88.00% 1 33.33%
Rusty Russell 3 12.00% 2 66.67%
Total 25 100.00% 3 100.00%


module_exit(virtio_net_driver_exit);

MODULE_DEVICE_TABLE(virtio, id_table);
MODULE_DESCRIPTION("Virtio network driver");
MODULE_LICENSE("GPL");
Overall Contributors
Person Tokens Prop Commits CommitProp
Jason (Hui) Wang 3036 24.95% 34 14.53%
John Fastabend 2013 16.54% 10 4.27%
Rusty Russell 1352 11.11% 32 13.68%
Michael S. Tsirkin 910 7.48% 33 14.10%
Michael Dalton 888 7.30% 6 2.56%
Alex Williamson 559 4.59% 9 3.85%
Shirley Ma 534 4.39% 2 0.85%
Mark McLoughlin 365 3.00% 4 1.71%
Sebastian Andrzej Siewior 316 2.60% 1 0.43%
Stephen Hemminger 316 2.60% 7 2.99%
Nikolay Aleksandrov 262 2.15% 2 0.85%
Amit Shah 227 1.87% 5 2.14%
Amos Kong 200 1.64% 3 1.28%
Wanlong Gao 177 1.45% 3 1.28%
Rick Jones 136 1.12% 4 1.71%
Andrew Lutomirski 83 0.68% 2 0.85%
Jiri Pirko 82 0.67% 9 3.85%
Herbert Xu 66 0.54% 3 1.28%
Sasha Levin 52 0.43% 3 1.28%
Eric Dumazet 51 0.42% 4 1.71%
Andrey Vagin 46 0.38% 2 0.85%
Mike Rapoport 45 0.37% 2 0.85%
Aaron Conole 43 0.35% 2 0.85%
Bruce Rogers 41 0.34% 1 0.43%
John Stultz 38 0.31% 1 0.43%
Daniel Borkmann 38 0.31% 1 0.43%
Jarod Wilson 31 0.25% 1 0.43%
Michał Mirosław 26 0.21% 1 0.43%
Vlad Yasevich 26 0.21% 1 0.43%
Christian Bornträger 20 0.16% 2 0.85%
Heinz Graalfs 19 0.16% 2 0.85%
David S. Miller 17 0.14% 4 1.71%
Thomas Huth 16 0.13% 2 0.85%
Johannes Berg 16 0.13% 3 1.28%
Dor Laor 14 0.12% 1 0.43%
Zhangjie \(HZ\) 12 0.10% 1 0.43%
Jacob E Keller 11 0.09% 1 0.43%
Linus Torvalds 8 0.07% 1 0.43%
Patrick McHardy 7 0.06% 2 0.85%
Krishna Kumar 7 0.06% 1 0.43%
Tejun Heo 7 0.06% 2 0.85%
Zhi Yong Wu 6 0.05% 1 0.43%
Eric W. Biedermann 5 0.04% 2 0.85%
Pantelis Koukousoulas 5 0.04% 1 0.43%
Américo Wang 5 0.04% 4 1.71%
Paolo Abeni 4 0.03% 1 0.43%
Pravin B Shelar 4 0.03% 1 0.43%
Wilfried Klaebe 3 0.02% 1 0.43%
Ben Hutchings 3 0.02% 1 0.43%
Shyam Saini 3 0.02% 1 0.43%
Wang Chen 2 0.02% 1 0.43%
Christoph Hellwig 2 0.02% 1 0.43%
Thomas Gleixner 2 0.02% 1 0.43%
wangyunjian 2 0.02% 1 0.43%
Aaron Lu 2 0.02% 1 0.43%
Jeff Kirsher 1 0.01% 1 0.43%
Li RongQing 1 0.01% 1 0.43%
Uwe Kleine-König 1 0.01% 1 0.43%
Danny Kukawka 1 0.01% 1 0.43%
Ira W. Snyder 1 0.01% 1 0.43%
Mike Waychison 1 0.01% 1 0.43%
Total 12167 100.00% 234 100.00%
Directory: drivers/net

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.
Person	Tokens	Prop	Commits	CommitProp
Jason (Hui) Wang	20	90.91%	1	50.00%
Rusty Russell	2	9.09%	1	50.00%
Total	22	100.00%	2	100.00%
cregit-Linux how code gets into the kernel

Release 4.11 drivers/net/virtio_net.c

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