Re: [PATCH v3] virtio/vsock: replace virtio_vsock_pkt with sk_buff

Stefano Garzarella
2022-11-18T08:36:26Z

On Fri, Nov 18, 2022 at 04:18:35AM +0000, Bobby Eshleman wrote:
>On Fri, Nov 11, 2022 at 01:24:11PM +0100, Stefano Garzarella wrote:
>> On Thu, Nov 10, 2022 at 09:17:22AM -0800, Bobby Eshleman wrote:
>> > This commit changes virtio/vsock to use sk_buff instead of
>> > virtio_vsock_pkt. Beyond better conforming to other net code, using
>> > sk_buff allows vsock to use sk_buff-dependent features in the future
>> > (such as sockmap) and improves throughput.
>> >
>> > This patch introduces the following performance changes:
>> >
>> > Tool/Config: uperf w/ 64 threads, SOCK_STREAM
>> > Test Runs: 5, mean of results
>> > Before: commit 95ec6bce2a0b ("Merge branch 'net-ipa-more-endpoints'")
>> >
>> > Test: 64KB, g2h
>> > Before: 21.63 Gb/s
>> > After: 25.59 Gb/s (+18%)
>> >
>> > Test: 16B, g2h
>> > Before: 11.86 Mb/s
>> > After: 17.41 Mb/s (+46%)
>> >
>> > Test: 64KB, h2g
>> > Before: 2.15 Gb/s
>> > After: 3.6 Gb/s (+67%)
>> >
>> > Test: 16B, h2g
>> > Before: 14.38 Mb/s
>> > After: 18.43 Mb/s (+28%)
>>
>> Nice, thanks for attaching perf numbers!
>>
>> I see similar variation also with iperf-vsock, but higher absolute values, I
>> think because of the different hardware or maybe because you're using nested
>> VMs.
>>
>> We have some regression (not because of this patch) in the h2g scenario, it
>> would be interesting to investigate. (I'll try next week)
>> When I did some performance analysis h2g was slower, because the host has to
>> split the packet according to the guest buffer (4K), while the guest can
>> queue the whole buffer, but not as much:
>> https://lore.kernel.org/lkml/20190730154334.237789-1-sgarzare@redhat.com/
>>
>
>This makes sense.
>
>> >
>> > Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
>>
>> checkpatch prints this warning, maybe you should fix the setup:
>>
>> $ ./scripts/checkpatch.pl --strict -g HEAD~1..HEAD
>> WARNING: From:/Signed-off-by: email address mismatch: 'From: Bobby Eshleman
>> <bobby.eshleman@gmail.com>' != 'Signed-off-by: Bobby Eshleman
>> <bobby.eshleman@bytedance.com>'
>>
>> > ---
>> > Changes in v3:
>> > - fix seqpacket bug
>> > - use zero in vhost_add_used(..., 0) device doesn't write to
>> > buffer
>> > - use xmas tree style declarations
>> > - vsock_hdr() -> virtio_vsock_hdr() and other include file style fixes
>> > - no skb merging
>> > - save space by not using vsock_metadata
>> > - use _skb_refdst instead of skb buffer space for flags
>> > - use skb_pull() to keep track of read bytes instead of
>> > using an an extra variable 'off' in the skb buffer space
>> > - remove unnecessary sk_allocation assignment
>> > - do not zero hdr needlessly
>> > - introduce virtio_transport_skb_len() because skb->len changes now
>> > - use spin_lock() directly on queue lock instead of sk_buff_head helpers
>> > which use spin_lock_irqsave() (e.g., skb_dequeue)
>> > - do not reduce buffer size to be page size divisible
>> > - Note: the biggest performance change came from loosening the spinlock
>> > variation and not reducing the buffer size.
>>
>> I was going to ask that, thanks for bringing it forward! :-)
>>
>> So it was spin_lock_irqsave vs spin_lock_bh, right?
>>
>
>Yep. I've got access to a better system to test this just week, so I'm
>got to test some theories as to why (nesting may require
>trap-and-emulate for the IRQ enable/disable register?). If anyone has
>some insights into why the save/restore lock variants would cause such a
>perf hit, I'd love to hear it.

I don't know the details, but I found this document useful:
Documentation/kernel-hacking/locking.rst

>
>> >
>> > Changes in v2:
>> > - Use alloc_skb() directly instead of sock_alloc_send_pskb() to minimize
>> > uAPI changes.
>> > - Do not marshal errors to -ENOMEM for non-virtio implementations.
>> > - No longer a part of the original series
>> > - Some code cleanup and refactoring
>> > - Include performance stats
>> >
>> > drivers/vhost/vsock.c | 222 +++++-------
>> > include/linux/virtio_vsock.h | 99 +++--
>> > net/vmw_vsock/virtio_transport.c | 160 ++++-----
>> > net/vmw_vsock/virtio_transport_common.c | 458 ++++++++++++------------
>> > net/vmw_vsock/vsock_loopback.c | 51 +--
>> > 5 files changed, 477 insertions(+), 513 deletions(-)
>> >
>> > diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
>> > index 5703775af129..cf6b67154072 100644
>> > --- a/drivers/vhost/vsock.c
>> > +++ b/drivers/vhost/vsock.c
>> > @@ -51,8 +51,7 @@ struct vhost_vsock {
>> > struct hlist_node hash;
>> >
>> > struct vhost_work send_pkt_work;
>> > - spinlock_t send_pkt_list_lock;
>> > - struct list_head send_pkt_list; /* host->guest pending packets */
>> > + struct sk_buff_head send_pkt_queue; /* host->guest pending packets */
>> >
>> > atomic_t queued_replies;
>> >
>> > @@ -108,40 +107,37 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
>> > vhost_disable_notify(&vsock->dev, vq);
>> >
>> > do {
>> > - struct virtio_vsock_pkt *pkt;
>> > + struct virtio_vsock_hdr *hdr;
>> > + size_t iov_len, payload_len;
>> > struct iov_iter iov_iter;
>> > + u32 flags_to_restore = 0;
>> > + struct sk_buff *skb;
>> > unsigned out, in;
>> > size_t nbytes;
>> > - size_t iov_len, payload_len;
>> > int head;
>> > - u32 flags_to_restore = 0;
>> >
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - if (list_empty(&vsock->send_pkt_list)) {
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>>
>> Could we continue to use spin_lock_bh()?
>>
>> The scenario hasn't changed, we have workqueue/tasklet vs user context and
>> looking at "Table of Minimum Requirements" in kernel-hacking/locking.rst, it
>> seems to be okay to use it.
>>
>
>Sure thing. Just for my own learning, may I ask where is this lock
>acquired in a tasklet? I could only find tasklet usage in vmci.

I was referring to the document where it talks about tasklets, which for
us are equirable to the workqueue that we use.

>
>> Perhaps we could add our helpers for queue_head, queue_tail, and dequeue.
>>
>
>To linux/skbuff.h or to linux/virtio_vsock.h?
>

In linux/virtio_vsock.h

>> > + skb = __skb_dequeue(&vsock->send_pkt_queue);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> > +
>> > + if (!skb) {
>> > vhost_enable_notify(&vsock->dev, vq);
>> > break;
>> > }
>> >
>> > - pkt = list_first_entry(&vsock->send_pkt_list,
>> > - struct virtio_vsock_pkt, list);
>> > - list_del_init(&pkt->list);
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > -
>> > head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
>> > &out, &in, NULL, NULL);
>> > if (head < 0) {
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - list_add(&pkt->list, &vsock->send_pkt_list);
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>> > + __skb_queue_head(&vsock->send_pkt_queue, skb);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> > break;
>> > }
>> >
>> > if (head == vq->num) {
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - list_add(&pkt->list, &vsock->send_pkt_list);
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > -
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>> > + __skb_queue_head(&vsock->send_pkt_queue, skb);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> > /* We cannot finish yet if more buffers snuck in while
>> > * re-enabling notify.
>> > */
>> > @@ -153,26 +149,27 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
>> > }
>> >
>> > if (out) {
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> > vq_err(vq, "Expected 0 output buffers, got %u\n", out);
>> > break;
>> > }
>> >
>> > iov_len = iov_length(&vq->iov[out], in);
>> > - if (iov_len < sizeof(pkt->hdr)) {
>> > - virtio_transport_free_pkt(pkt);
>> > + if (iov_len < sizeof(*hdr)) {
>> > + virtio_vsock_kfree_skb(skb);
>> > vq_err(vq, "Buffer len [%zu] too small\n", iov_len);
>> > break;
>> > }
>> >
>> > iov_iter_init(&iov_iter, READ, &vq->iov[out], in, iov_len);
>> > - payload_len = pkt->len - pkt->off;
>> > + payload_len = skb->len;
>> > + hdr = virtio_vsock_hdr(skb);
>> >
>> > /* If the packet is greater than the space available in the
>> > * buffer, we split it using multiple buffers.
>> > */
>> > - if (payload_len > iov_len - sizeof(pkt->hdr)) {
>> > - payload_len = iov_len - sizeof(pkt->hdr);
>> > + if (payload_len > iov_len - sizeof(*hdr)) {
>> > + payload_len = iov_len - sizeof(*hdr);
>> >
>> > /* As we are copying pieces of large packet's buffer to
>> > * small rx buffers, headers of packets in rx queue are
>> > @@ -185,31 +182,30 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
>> > * bits set. After initialized header will be copied to
>> > * rx buffer, these required bits will be restored.
>> > */
>> > - if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOM) {
>> > - pkt->hdr.flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOM);
>> > + if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SEQ_EOM) {
>> > + hdr->flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOM);
>> > flags_to_restore |= VIRTIO_VSOCK_SEQ_EOM;
>> >
>> > - if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOR) {
>> > - pkt->hdr.flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR);
>> > + if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SEQ_EOR) {
>> > + hdr->flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR);
>> > flags_to_restore |= VIRTIO_VSOCK_SEQ_EOR;
>> > }
>> > }
>> > }
>> >
>> > /* Set the correct length in the header */
>> > - pkt->hdr.len = cpu_to_le32(payload_len);
>> > + hdr->len = cpu_to_le32(payload_len);
>> >
>> > - nbytes = copy_to_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter);
>> > - if (nbytes != sizeof(pkt->hdr)) {
>> > - virtio_transport_free_pkt(pkt);
>> > + nbytes = copy_to_iter(hdr, sizeof(*hdr), &iov_iter);
>> > + if (nbytes != sizeof(*hdr)) {
>> > + virtio_vsock_kfree_skb(skb);
>> > vq_err(vq, "Faulted on copying pkt hdr\n");
>> > break;
>> > }
>> >
>> > - nbytes = copy_to_iter(pkt->buf + pkt->off, payload_len,
>> > - &iov_iter);
>> > + nbytes = copy_to_iter(skb->data, payload_len, &iov_iter);
>> > if (nbytes != payload_len) {
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> > vq_err(vq, "Faulted on copying pkt buf\n");
>> > break;
>> > }
>> > @@ -217,31 +213,30 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
>> > /* Deliver to monitoring devices all packets that we
>> > * will transmit.
>> > */
>> > - virtio_transport_deliver_tap_pkt(pkt);
>> > + virtio_transport_deliver_tap_pkt(skb);
>> >
>> > - vhost_add_used(vq, head, sizeof(pkt->hdr) + payload_len);
>> > + vhost_add_used(vq, head, sizeof(*hdr) + payload_len);
>> > added = true;
>> >
>> > - pkt->off += payload_len;
>> > + skb_pull(skb, payload_len);
>> > total_len += payload_len;
>> >
>> > /* If we didn't send all the payload we can requeue the packet
>> > * to send it with the next available buffer.
>> > */
>> > - if (pkt->off < pkt->len) {
>> > - pkt->hdr.flags |= cpu_to_le32(flags_to_restore);
>> > + if (skb->len > 0) {
>> > + hdr->flags |= cpu_to_le32(flags_to_restore);
>> >
>> > - /* We are queueing the same virtio_vsock_pkt to handle
>> > + /* We are queueing the same skb to handle
>> > * the remaining bytes, and we want to deliver it
>> > * to monitoring devices in the next iteration.
>> > */
>> > - pkt->tap_delivered = false;
>> > -
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - list_add(&pkt->list, &vsock->send_pkt_list);
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > + virtio_vsock_skb_clear_tap_delivered(skb);
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>> > + __skb_queue_head(&vsock->send_pkt_queue, skb);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> > } else {
>> > - if (pkt->reply) {
>> > + if (virtio_vsock_skb_reply(skb)) {
>> > int val;
>> >
>> > val = atomic_dec_return(&vsock->queued_replies);
>> > @@ -253,7 +248,7 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
>> > restart_tx = true;
>> > }
>> >
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_consume_skb(skb);
>> > }
>> > } while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));
>> > if (added)
>> > @@ -278,28 +273,28 @@ static void vhost_transport_send_pkt_work(struct vhost_work *work)
>> > }
>> >
>> > static int
>> > -vhost_transport_send_pkt(struct virtio_vsock_pkt *pkt)
>> > +vhost_transport_send_pkt(struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct vhost_vsock *vsock;
>> > - int len = pkt->len;
>> > + int len = skb->len;
>> >
>> > rcu_read_lock();
>> >
>> > /* Find the vhost_vsock according to guest context id */
>> > - vsock = vhost_vsock_get(le64_to_cpu(pkt->hdr.dst_cid));
>> > + vsock = vhost_vsock_get(le64_to_cpu(hdr->dst_cid));
>> > if (!vsock) {
>> > rcu_read_unlock();
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> > return -ENODEV;
>> > }
>> >
>> > - if (pkt->reply)
>> > + if (virtio_vsock_skb_reply(skb))
>> > atomic_inc(&vsock->queued_replies);
>> >
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - list_add_tail(&pkt->list, &vsock->send_pkt_list);
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > -
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>>
>>
>>
>> > + __skb_queue_tail(&vsock->send_pkt_queue, skb);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> > vhost_work_queue(&vsock->dev, &vsock->send_pkt_work);
>> >
>> > rcu_read_unlock();
>> > @@ -310,10 +305,8 @@ static int
>> > vhost_transport_cancel_pkt(struct vsock_sock *vsk)
>> > {
>> > struct vhost_vsock *vsock;
>> > - struct virtio_vsock_pkt *pkt, *n;
>> > int cnt = 0;
>> > int ret = -ENODEV;
>> > - LIST_HEAD(freeme);
>> >
>> > rcu_read_lock();
>> >
>> > @@ -322,20 +315,7 @@ vhost_transport_cancel_pkt(struct vsock_sock *vsk)
>> > if (!vsock)
>> > goto out;
>> >
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - list_for_each_entry_safe(pkt, n, &vsock->send_pkt_list, list) {
>> > - if (pkt->vsk != vsk)
>> > - continue;
>> > - list_move(&pkt->list, &freeme);
>> > - }
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > -
>> > - list_for_each_entry_safe(pkt, n, &freeme, list) {
>> > - if (pkt->reply)
>> > - cnt++;
>> > - list_del(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > - }
>> > + cnt = virtio_transport_purge_skbs(vsk, &vsock->send_pkt_queue);
>> >
>> > if (cnt) {
>> > struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX];
>> > @@ -352,12 +332,14 @@ vhost_transport_cancel_pkt(struct vsock_sock *vsk)
>> > return ret;
>> > }
>> >
>> > -static struct virtio_vsock_pkt *
>> > -vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq,
>> > +static struct sk_buff *
>> > +vhost_vsock_alloc_skb(struct vhost_virtqueue *vq,
>> > unsigned int out, unsigned int in)
>> > {
>> > - struct virtio_vsock_pkt *pkt;
>> > + struct virtio_vsock_hdr *hdr;
>> > struct iov_iter iov_iter;
>> > + struct sk_buff *skb;
>> > + size_t payload_len;
>> > size_t nbytes;
>> > size_t len;
>> >
>> > @@ -366,50 +348,48 @@ vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq,
>> > return NULL;
>> > }
>> >
>> > - pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
>> > - if (!pkt)
>> > + len = iov_length(vq->iov, out);
>> > +
>> > + /* len contains both payload and hdr */
>> > + skb = alloc_skb(len, GFP_KERNEL);
>> > + if (!skb)
>> > return NULL;
>> >
>> > - len = iov_length(vq->iov, out);
>> > + skb_reserve(skb, VIRTIO_VSOCK_SKB_HEADROOM);
>>
>> What about a virtio_vsock_alloc_skb() where we call alloc_skb() and
>> skb_reserve()?
>>
>> Then we can reuse it in all the places where we allocate the skb.
>
>I think that makes sense.
>
>>
>> > iov_iter_init(&iov_iter, WRITE, vq->iov, out, len);
>> >
>> > - nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter);
>> > - if (nbytes != sizeof(pkt->hdr)) {
>> > + hdr = virtio_vsock_hdr(skb);
>> > + nbytes = copy_from_iter(hdr, sizeof(*hdr), &iov_iter);
>> > + if (nbytes != sizeof(*hdr)) {
>> > vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n",
>> > - sizeof(pkt->hdr), nbytes);
>> > - kfree(pkt);
>> > + sizeof(*hdr), nbytes);
>> > + virtio_vsock_kfree_skb(skb);
>> > return NULL;
>> > }
>> >
>> > - pkt->len = le32_to_cpu(pkt->hdr.len);
>> > + payload_len = le32_to_cpu(hdr->len);
>> >
>> > /* No payload */
>> > - if (!pkt->len)
>> > - return pkt;
>> > + if (!payload_len)
>> > + return skb;
>> >
>> > /* The pkt is too big */
>> > - if (pkt->len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
>> > - kfree(pkt);
>> > + if (payload_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
>> > + virtio_vsock_kfree_skb(skb);
>> > return NULL;
>> > }
>> >
>> > - pkt->buf = kvmalloc(pkt->len, GFP_KERNEL);
>> > - if (!pkt->buf) {
>> > - kfree(pkt);
>> > - return NULL;
>> > - }
>> > + virtio_vsock_skb_rx_put(skb);
>> >
>> > - pkt->buf_len = pkt->len;
>> > -
>> > - nbytes = copy_from_iter(pkt->buf, pkt->len, &iov_iter);
>> > - if (nbytes != pkt->len) {
>> > - vq_err(vq, "Expected %u byte payload, got %zu bytes\n",
>> > - pkt->len, nbytes);
>> > - virtio_transport_free_pkt(pkt);
>> > + nbytes = copy_from_iter(skb->data, payload_len, &iov_iter);
>> > + if (nbytes != payload_len) {
>> > + vq_err(vq, "Expected %zu byte payload, got %zu bytes\n",
>> > + payload_len, nbytes);
>> > + virtio_vsock_kfree_skb(skb);
>> > return NULL;
>> > }
>> >
>> > - return pkt;
>> > + return skb;
>> > }
>> >
>> > /* Is there space left for replies to rx packets? */
>> > @@ -496,9 +476,9 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
>> > poll.work);
>> > struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
>> > dev);
>> > - struct virtio_vsock_pkt *pkt;
>> > int head, pkts = 0, total_len = 0;
>> > unsigned int out, in;
>> > + struct sk_buff *skb;
>> > bool added = false;
>> >
>> > mutex_lock(&vq->mutex);
>> > @@ -511,6 +491,8 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
>> >
>> > vhost_disable_notify(&vsock->dev, vq);
>> > do {
>> > + struct virtio_vsock_hdr *hdr;
>> > +
>> > if (!vhost_vsock_more_replies(vsock)) {
>> > /* Stop tx until the device processes already
>> > * pending replies. Leave tx virtqueue
>> > @@ -532,24 +514,26 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
>> > break;
>> > }
>> >
>> > - pkt = vhost_vsock_alloc_pkt(vq, out, in);
>> > - if (!pkt) {
>> > + skb = vhost_vsock_alloc_skb(vq, out, in);
>> > + if (!skb) {
>> > vq_err(vq, "Faulted on pkt\n");
>> > continue;
>> > }
>> >
>> > - total_len += sizeof(pkt->hdr) + pkt->len;
>> > + total_len += sizeof(*hdr) + skb->len;
>> >
>> > /* Deliver to monitoring devices all received packets */
>> > - virtio_transport_deliver_tap_pkt(pkt);
>> > + virtio_transport_deliver_tap_pkt(skb);
>> > +
>> > + hdr = virtio_vsock_hdr(skb);
>> >
>> > /* Only accept correctly addressed packets */
>> > - if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid &&
>> > - le64_to_cpu(pkt->hdr.dst_cid) ==
>> > + if (le64_to_cpu(hdr->src_cid) == vsock->guest_cid &&
>> > + le64_to_cpu(hdr->dst_cid) ==
>> > vhost_transport_get_local_cid())
>> > - virtio_transport_recv_pkt(&vhost_transport, pkt);
>> > + virtio_transport_recv_pkt(&vhost_transport, skb);
>> > else
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> >
>> > vhost_add_used(vq, head, 0);
>> > added = true;
>> > @@ -693,8 +677,7 @@ static int vhost_vsock_dev_open(struct inode *inode, struct file *file)
>> > VHOST_VSOCK_WEIGHT, true, NULL);
>> >
>> > file->private_data = vsock;
>> > - spin_lock_init(&vsock->send_pkt_list_lock);
>> > - INIT_LIST_HEAD(&vsock->send_pkt_list);
>> > + skb_queue_head_init(&vsock->send_pkt_queue);
>> > vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work);
>> > return 0;
>> >
>> > @@ -760,16 +743,7 @@ static int vhost_vsock_dev_release(struct inode *inode, struct file *file)
>> > vhost_vsock_flush(vsock);
>> > vhost_dev_stop(&vsock->dev);
>> >
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - while (!list_empty(&vsock->send_pkt_list)) {
>> > - struct virtio_vsock_pkt *pkt;
>> > -
>> > - pkt = list_first_entry(&vsock->send_pkt_list,
>> > - struct virtio_vsock_pkt, list);
>> > - list_del_init(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > - }
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > + virtio_vsock_skb_queue_purge(&vsock->send_pkt_queue);
>> >
>> > vhost_dev_cleanup(&vsock->dev);
>> > kfree(vsock->dev.vqs);
>> > diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
>> > index 35d7eedb5e8e..17e1cb8c91b2 100644
>> > --- a/include/linux/virtio_vsock.h
>> > +++ b/include/linux/virtio_vsock.h
>> > @@ -4,9 +4,82 @@
>> >
>> > #include <uapi/linux/virtio_vsock.h>
>> > #include <linux/socket.h>
>> > +#include <vdso/bits.h>
>> > #include <net/sock.h>
>> > #include <net/af_vsock.h>
>> >
>> > +#define VIRTIO_VSOCK_SKB_HEADROOM (sizeof(struct virtio_vsock_hdr))
>> > +
>> > +enum virtio_vsock_skb_flags {
>> > + VIRTIO_VSOCK_SKB_FLAGS_REPLY = BIT(0),
>> > + VIRTIO_VSOCK_SKB_FLAGS_TAP_DELIVERED = BIT(1),
>> > +};
>> > +
>> > +static inline struct virtio_vsock_hdr *virtio_vsock_hdr(struct sk_buff *skb)
>> > +{
>> > + return (struct virtio_vsock_hdr *)skb->head;
>> > +}
>> > +
>> > +static inline bool virtio_vsock_skb_reply(struct sk_buff *skb)
>> > +{
>> > + return skb->_skb_refdst & VIRTIO_VSOCK_SKB_FLAGS_REPLY;
>> > +}
>> > +
>> > +static inline void virtio_vsock_skb_set_reply(struct sk_buff *skb)
>> > +{
>> > + skb->_skb_refdst |= VIRTIO_VSOCK_SKB_FLAGS_REPLY;
>> > +}
>> > +
>> > +static inline bool virtio_vsock_skb_tap_delivered(struct sk_buff *skb)
>> > +{
>> > + return skb->_skb_refdst & VIRTIO_VSOCK_SKB_FLAGS_TAP_DELIVERED;
>> > +}
>> > +
>> > +static inline void virtio_vsock_skb_set_tap_delivered(struct sk_buff *skb)
>> > +{
>> > + skb->_skb_refdst |= VIRTIO_VSOCK_SKB_FLAGS_TAP_DELIVERED;
>> > +}
>> > +
>> > +static inline void virtio_vsock_skb_clear_tap_delivered(struct sk_buff *skb)
>> > +{
>> > + skb->_skb_refdst &= ~VIRTIO_VSOCK_SKB_FLAGS_TAP_DELIVERED;
>> > +}
>> > +
>> > +static inline void virtio_vsock_skb_rx_put(struct sk_buff *skb)
>> > +{
>> > + u32 len;
>> > +
>> > + len = le32_to_cpu(virtio_vsock_hdr(skb)->len);
>> > +
>> > + if (len > 0)
>> > + skb_put(skb, len);
>> > +}
>> > +
>> > +static inline void virtio_vsock_kfree_skb(struct sk_buff *skb)
>> > +{
>> > + skb->_skb_refdst = 0;
>> > + kfree_skb(skb);
>> > +}
>> > +
>> > +static inline void virtio_vsock_skb_queue_purge(struct sk_buff_head *queue)
>> > +{
>> > + struct sk_buff *skb;
>> > +
>> > + while ((skb = __skb_dequeue(queue)) != NULL)
>> > + virtio_vsock_kfree_skb(skb);
>> > +}
>> > +
>> > +static inline size_t virtio_vsock_skb_len(struct sk_buff *skb)
>> > +{
>> > + return (size_t)(skb_end_pointer(skb) - skb->head);
>> > +}
>> > +
>> > +static inline void virtio_vsock_consume_skb(struct sk_buff *skb)
>> > +{
>> > + skb->_skb_refdst = 0;
>> > + consume_skb(skb);
>> > +}
>> > +
>> > #define VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE (1024 * 4)
>> > #define VIRTIO_VSOCK_MAX_BUF_SIZE 0xFFFFFFFFUL
>> > #define VIRTIO_VSOCK_MAX_PKT_BUF_SIZE (1024 * 64)
>> > @@ -35,23 +108,10 @@ struct virtio_vsock_sock {
>> > u32 last_fwd_cnt;
>> > u32 rx_bytes;
>> > u32 buf_alloc;
>> > - struct list_head rx_queue;
>> > + struct sk_buff_head rx_queue;
>> > u32 msg_count;
>> > };
>> >
>> > -struct virtio_vsock_pkt {
>> > - struct virtio_vsock_hdr hdr;
>> > - struct list_head list;
>> > - /* socket refcnt not held, only use for cancellation */
>> > - struct vsock_sock *vsk;
>> > - void *buf;
>> > - u32 buf_len;
>> > - u32 len;
>> > - u32 off;
>> > - bool reply;
>> > - bool tap_delivered;
>> > -};
>> > -
>> > struct virtio_vsock_pkt_info {
>> > u32 remote_cid, remote_port;
>> > struct vsock_sock *vsk;
>> > @@ -68,7 +128,7 @@ struct virtio_transport {
>> > struct vsock_transport transport;
>> >
>> > /* Takes ownership of the packet */
>> > - int (*send_pkt)(struct virtio_vsock_pkt *pkt);
>> > + int (*send_pkt)(struct sk_buff *skb);
>> > };
>> >
>> > ssize_t
>> > @@ -149,11 +209,10 @@ virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
>> > void virtio_transport_destruct(struct vsock_sock *vsk);
>> >
>> > void virtio_transport_recv_pkt(struct virtio_transport *t,
>> > - struct virtio_vsock_pkt *pkt);
>> > -void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt);
>> > -void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt);
>> > + struct sk_buff *skb);
>> > +void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct sk_buff *skb);
>> > u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 wanted);
>> > void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit);
>> > -void virtio_transport_deliver_tap_pkt(struct virtio_vsock_pkt *pkt);
>> > -
>> > +void virtio_transport_deliver_tap_pkt(struct sk_buff *skb);
>> > +int virtio_transport_purge_skbs(void *vsk, struct sk_buff_head *queue);
>> > #endif /* _LINUX_VIRTIO_VSOCK_H */
>> > diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
>> > index ad64f403536a..172dbc52a370 100644
>> > --- a/net/vmw_vsock/virtio_transport.c
>> > +++ b/net/vmw_vsock/virtio_transport.c
>> > @@ -42,8 +42,7 @@ struct virtio_vsock {
>> > bool tx_run;
>> >
>> > struct work_struct send_pkt_work;
>> > - spinlock_t send_pkt_list_lock;
>> > - struct list_head send_pkt_list;
>> > + struct sk_buff_head send_pkt_queue;
>> >
>> > atomic_t queued_replies;
>> >
>> > @@ -101,41 +100,36 @@ virtio_transport_send_pkt_work(struct work_struct *work)
>> > vq = vsock->vqs[VSOCK_VQ_TX];
>> >
>> > for (;;) {
>> > - struct virtio_vsock_pkt *pkt;
>> > struct scatterlist hdr, buf, *sgs[2];
>> > int ret, in_sg = 0, out_sg = 0;
>> > + struct sk_buff *skb;
>> > bool reply;
>> >
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - if (list_empty(&vsock->send_pkt_list)) {
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > - break;
>> > - }
>> > -
>> > - pkt = list_first_entry(&vsock->send_pkt_list,
>> > - struct virtio_vsock_pkt, list);
>> > - list_del_init(&pkt->list);
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>> > + skb = __skb_dequeue(&vsock->send_pkt_queue);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> >
>> > - virtio_transport_deliver_tap_pkt(pkt);
>> > + if (!skb)
>> > + break;
>> >
>> > - reply = pkt->reply;
>> > + virtio_transport_deliver_tap_pkt(skb);
>> > + reply = virtio_vsock_skb_reply(skb);
>> >
>> > - sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr));
>> > + sg_init_one(&hdr, virtio_vsock_hdr(skb), sizeof(*virtio_vsock_hdr(skb)));
>> > sgs[out_sg++] = &hdr;
>> > - if (pkt->buf) {
>> > - sg_init_one(&buf, pkt->buf, pkt->len);
>> > + if (skb->len > 0) {
>> > + sg_init_one(&buf, skb->data, skb->len);
>> > sgs[out_sg++] = &buf;
>> > }
>> >
>> > - ret = virtqueue_add_sgs(vq, sgs, out_sg, in_sg, pkt, GFP_KERNEL);
>> > + ret = virtqueue_add_sgs(vq, sgs, out_sg, in_sg, skb, GFP_KERNEL);
>> > /* Usually this means that there is no more space available in
>> > * the vq
>> > */
>> > if (ret < 0) {
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - list_add(&pkt->list, &vsock->send_pkt_list);
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>> > + __skb_queue_head(&vsock->send_pkt_queue, skb);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> > break;
>> > }
>> >
>> > @@ -164,32 +158,34 @@ virtio_transport_send_pkt_work(struct work_struct *work)
>> > }
>> >
>> > static int
>> > -virtio_transport_send_pkt(struct virtio_vsock_pkt *pkt)
>> > +virtio_transport_send_pkt(struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr;
>> > struct virtio_vsock *vsock;
>> > - int len = pkt->len;
>> > + int len = skb->len;
>> > +
>> > + hdr = virtio_vsock_hdr(skb);
>> >
>> > rcu_read_lock();
>> > vsock = rcu_dereference(the_virtio_vsock);
>> > if (!vsock) {
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> > len = -ENODEV;
>> > goto out_rcu;
>> > }
>> >
>> > - if (le64_to_cpu(pkt->hdr.dst_cid) == vsock->guest_cid) {
>> > - virtio_transport_free_pkt(pkt);
>> > + if (le64_to_cpu(hdr->dst_cid) == vsock->guest_cid) {
>> > + virtio_vsock_kfree_skb(skb);
>> > len = -ENODEV;
>> > goto out_rcu;
>> > }
>> >
>> > - if (pkt->reply)
>> > + if (virtio_vsock_skb_reply(skb))
>> > atomic_inc(&vsock->queued_replies);
>> >
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - list_add_tail(&pkt->list, &vsock->send_pkt_list);
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > -
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>> > + __skb_queue_tail(&vsock->send_pkt_queue, skb);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> > queue_work(virtio_vsock_workqueue, &vsock->send_pkt_work);
>> >
>> > out_rcu:
>> > @@ -201,9 +197,7 @@ static int
>> > virtio_transport_cancel_pkt(struct vsock_sock *vsk)
>> > {
>> > struct virtio_vsock *vsock;
>> > - struct virtio_vsock_pkt *pkt, *n;
>> > int cnt = 0, ret;
>> > - LIST_HEAD(freeme);
>> >
>> > rcu_read_lock();
>> > vsock = rcu_dereference(the_virtio_vsock);
>> > @@ -212,20 +206,7 @@ virtio_transport_cancel_pkt(struct vsock_sock *vsk)
>> > goto out_rcu;
>> > }
>> >
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - list_for_each_entry_safe(pkt, n, &vsock->send_pkt_list, list) {
>> > - if (pkt->vsk != vsk)
>> > - continue;
>> > - list_move(&pkt->list, &freeme);
>> > - }
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > -
>> > - list_for_each_entry_safe(pkt, n, &freeme, list) {
>> > - if (pkt->reply)
>> > - cnt++;
>> > - list_del(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > - }
>> > + cnt = virtio_transport_purge_skbs(vsk, &vsock->send_pkt_queue);
>> >
>> > if (cnt) {
>> > struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX];
>> > @@ -246,38 +227,29 @@ virtio_transport_cancel_pkt(struct vsock_sock *vsk)
>> >
>> > static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
>> > {
>> > - int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
>> > - struct virtio_vsock_pkt *pkt;
>> > - struct scatterlist hdr, buf, *sgs[2];
>> > + int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE +
>>
>> Since we are changing the meaning, maybe we can rename this variable in
>> total_len or skb_data_len, what do you think?
>>
>> > VIRTIO_VSOCK_SKB_HEADROOM;
>> > + struct scatterlist pkt, *p;
>> > struct virtqueue *vq;
>> > + struct sk_buff *skb;
>> > int ret;
>> >
>> > vq = vsock->vqs[VSOCK_VQ_RX];
>> >
>> > do {
>> > - pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
>> > - if (!pkt)
>> > + skb = alloc_skb(buf_len, GFP_KERNEL);
>> > + if (!skb)
>> > break;
>> >
>>
>> Why don't we call skb_reserve() here, but do it later in
>> virtio_transport_rx_work()?
>>
>> If we add virtio_vsock_alloc_skb(), I think we can reuse it also here.
>>
>
>Good point, I was trying to keep the calls that adjust the skb data/tail
>pointers in one place, but I agree that skb_reserve() really belongs in
>a helper with the allocation.
>
>>
>> > - pkt->buf = kmalloc(buf_len, GFP_KERNEL);
>> > - if (!pkt->buf) {
>> > - virtio_transport_free_pkt(pkt);
>> > - break;
>> > - }
>> > -
>> > - pkt->buf_len = buf_len;
>> > - pkt->len = buf_len;
>> > -
>> > - sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr));
>> > - sgs[0] = &hdr;
>> > + memset(skb->head, 0, VIRTIO_VSOCK_SKB_HEADROOM);
>> >
>> > - sg_init_one(&buf, pkt->buf, buf_len);
>> > - sgs[1] = &buf;
>> > - ret = virtqueue_add_sgs(vq, sgs, 0, 2, pkt, GFP_KERNEL);
>> > - if (ret) {
>> > - virtio_transport_free_pkt(pkt);
>> > + sg_init_one(&pkt, virtio_vsock_hdr(skb), buf_len);
>> > + p = &pkt;
>> > + ret = virtqueue_add_sgs(vq, &p, 0, 1, skb, GFP_KERNEL);
>> > + if (ret < 0) {
>> > + virtio_vsock_kfree_skb(skb);
>> > break;
>> > }
>> > +
>> > vsock->rx_buf_nr++;
>> > } while (vq->num_free);
>> > if (vsock->rx_buf_nr > vsock->rx_buf_max_nr)
>> > @@ -299,12 +271,12 @@ static void virtio_transport_tx_work(struct work_struct *work)
>> > goto out;
>> >
>> > do {
>> > - struct virtio_vsock_pkt *pkt;
>> > + struct sk_buff *skb;
>> > unsigned int len;
>> >
>> > virtqueue_disable_cb(vq);
>> > - while ((pkt = virtqueue_get_buf(vq, &len)) != NULL) {
>> > - virtio_transport_free_pkt(pkt);
>> > + while ((skb = virtqueue_get_buf(vq, &len)) != NULL) {
>> > + virtio_vsock_consume_skb(skb);
>> > added = true;
>> > }
>> > } while (!virtqueue_enable_cb(vq));
>> > @@ -529,7 +501,7 @@ static void virtio_transport_rx_work(struct work_struct *work)
>> > do {
>> > virtqueue_disable_cb(vq);
>> > for (;;) {
>> > - struct virtio_vsock_pkt *pkt;
>> > + struct sk_buff *skb;
>> > unsigned int len;
>> >
>> > if (!virtio_transport_more_replies(vsock)) {
>> > @@ -540,23 +512,23 @@ static void virtio_transport_rx_work(struct work_struct *work)
>> > goto out;
>> > }
>> >
>> > - pkt = virtqueue_get_buf(vq, &len);
>> > - if (!pkt) {
>> > + skb = virtqueue_get_buf(vq, &len);
>> > + if (!skb)
>> > break;
>> > - }
>> >
>> > vsock->rx_buf_nr--;
>> >
>> > /* Drop short/long packets */
>> > - if (unlikely(len < sizeof(pkt->hdr) ||
>> > - len > sizeof(pkt->hdr) + pkt->len)) {
>> > - virtio_transport_free_pkt(pkt);
>> > + if (unlikely(len < sizeof(struct virtio_vsock_hdr) ||
>> > + len > virtio_vsock_skb_len(skb))) {
>> > + virtio_vsock_kfree_skb(skb);
>> > continue;
>> > }
>> >
>> > - pkt->len = len - sizeof(pkt->hdr);
>> > - virtio_transport_deliver_tap_pkt(pkt);
>> > - virtio_transport_recv_pkt(&virtio_transport, pkt);
>> > + skb_reserve(skb, VIRTIO_VSOCK_SKB_HEADROOM);
>> > + virtio_vsock_skb_rx_put(skb);
>> > + virtio_transport_deliver_tap_pkt(skb);
>> > + virtio_transport_recv_pkt(&virtio_transport, skb);
>> > }
>> > } while (!virtqueue_enable_cb(vq));
>> >
>> > @@ -610,7 +582,7 @@ static int virtio_vsock_vqs_init(struct virtio_vsock *vsock)
>> > static void virtio_vsock_vqs_del(struct virtio_vsock *vsock)
>> > {
>> > struct virtio_device *vdev = vsock->vdev;
>> > - struct virtio_vsock_pkt *pkt;
>> > + struct sk_buff *skb;
>> >
>> > /* Reset all connected sockets when the VQs disappear */
>> > vsock_for_each_connected_socket(&virtio_transport.transport,
>> > @@ -637,23 +609,18 @@ static void virtio_vsock_vqs_del(struct virtio_vsock *vsock)
>> > virtio_reset_device(vdev);
>> >
>> > mutex_lock(&vsock->rx_lock);
>> > - while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_RX])))
>> > - virtio_transport_free_pkt(pkt);
>> > + while ((skb = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_RX])))
>> > + virtio_vsock_kfree_skb(skb);
>> > mutex_unlock(&vsock->rx_lock);
>> >
>> > mutex_lock(&vsock->tx_lock);
>> > - while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_TX])))
>> > - virtio_transport_free_pkt(pkt);
>> > + while ((skb = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_TX])))
>> > + virtio_vsock_kfree_skb(skb);
>> > mutex_unlock(&vsock->tx_lock);
>> >
>> > - spin_lock_bh(&vsock->send_pkt_list_lock);
>> > - while (!list_empty(&vsock->send_pkt_list)) {
>> > - pkt = list_first_entry(&vsock->send_pkt_list,
>> > - struct virtio_vsock_pkt, list);
>> > - list_del(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > - }
>> > - spin_unlock_bh(&vsock->send_pkt_list_lock);
>> > + spin_lock(&vsock->send_pkt_queue.lock);
>> > + virtio_vsock_skb_queue_purge(&vsock->send_pkt_queue);
>> > + spin_unlock(&vsock->send_pkt_queue.lock);
>> >
>> > /* Delete virtqueues and flush outstanding callbacks if any */
>> > vdev->config->del_vqs(vdev);
>> > @@ -690,8 +657,7 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
>> > mutex_init(&vsock->tx_lock);
>> > mutex_init(&vsock->rx_lock);
>> > mutex_init(&vsock->event_lock);
>> > - spin_lock_init(&vsock->send_pkt_list_lock);
>> > - INIT_LIST_HEAD(&vsock->send_pkt_list);
>> > + skb_queue_head_init(&vsock->send_pkt_queue);
>> > INIT_WORK(&vsock->rx_work, virtio_transport_rx_work);
>> > INIT_WORK(&vsock->tx_work, virtio_transport_tx_work);
>> > INIT_WORK(&vsock->event_work, virtio_transport_event_work);
>> > diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
>> > index a9980e9b9304..b40a17cbbccf 100644
>> > --- a/net/vmw_vsock/virtio_transport_common.c
>> > +++ b/net/vmw_vsock/virtio_transport_common.c
>> > @@ -37,53 +37,58 @@ virtio_transport_get_ops(struct vsock_sock *vsk)
>> > return container_of(t, struct virtio_transport, transport);
>> > }
>> >
>> > -static struct virtio_vsock_pkt *
>> > -virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
>> > +/* Returns a new packet on success, otherwise returns NULL.
>> > + *
>> > + * If NULL is returned, errp is set to a negative errno.
>> > + */
>> > +static struct sk_buff *
>> > +virtio_transport_alloc_skb(struct virtio_vsock_pkt_info *info,
>> > size_t len,
>> > u32 src_cid,
>> > u32 src_port,
>> > u32 dst_cid,
>> > u32 dst_port)
>> > {
>> > - struct virtio_vsock_pkt *pkt;
>> > + const size_t skb_len = VIRTIO_VSOCK_SKB_HEADROOM + len;
>> > + struct virtio_vsock_hdr *hdr;
>> > + struct sk_buff *skb;
>> > + void *payload;
>> > int err;
>> >
>> > - pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
>> > - if (!pkt)
>> > + skb = alloc_skb(skb_len, GFP_KERNEL);
>> > + if (!skb)
>> > return NULL;
>> >
>> > - pkt->hdr.type = cpu_to_le16(info->type);
>> > - pkt->hdr.op = cpu_to_le16(info->op);
>> > - pkt->hdr.src_cid = cpu_to_le64(src_cid);
>> > - pkt->hdr.dst_cid = cpu_to_le64(dst_cid);
>> > - pkt->hdr.src_port = cpu_to_le32(src_port);
>> > - pkt->hdr.dst_port = cpu_to_le32(dst_port);
>> > - pkt->hdr.flags = cpu_to_le32(info->flags);
>> > - pkt->len = len;
>> > - pkt->hdr.len = cpu_to_le32(len);
>> > - pkt->reply = info->reply;
>> > - pkt->vsk = info->vsk;
>> > + skb_reserve(skb, VIRTIO_VSOCK_SKB_HEADROOM);
>> > + payload = skb_put(skb, len);
>> >
>> > - if (info->msg && len > 0) {
>> > - pkt->buf = kmalloc(len, GFP_KERNEL);
>> > - if (!pkt->buf)
>> > - goto out_pkt;
>> > -
>> > - pkt->buf_len = len;
>> > + hdr = virtio_vsock_hdr(skb);
>> > + hdr->type = cpu_to_le16(info->type);
>> > + hdr->op = cpu_to_le16(info->op);
>> > + hdr->src_cid = cpu_to_le64(src_cid);
>> > + hdr->dst_cid = cpu_to_le64(dst_cid);
>> > + hdr->src_port = cpu_to_le32(src_port);
>> > + hdr->dst_port = cpu_to_le32(dst_port);
>> > + hdr->flags = cpu_to_le32(info->flags);
>> > + hdr->len = cpu_to_le32(len);
>> >
>> > - err = memcpy_from_msg(pkt->buf, info->msg, len);
>> > + if (info->msg && len > 0) {
>> > + err = memcpy_from_msg(payload, info->msg, len);
>> > if (err)
>> > goto out;
>> >
>> > if (msg_data_left(info->msg) == 0 &&
>> > info->type == VIRTIO_VSOCK_TYPE_SEQPACKET) {
>> > - pkt->hdr.flags |= cpu_to_le32(VIRTIO_VSOCK_SEQ_EOM);
>> > + hdr->flags |= cpu_to_le32(VIRTIO_VSOCK_SEQ_EOM);
>> >
>> > if (info->msg->msg_flags & MSG_EOR)
>> > - pkt->hdr.flags |= cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR);
>> > + hdr->flags |= cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR);
>> > }
>> > }
>> >
>> > + if (info->reply)
>> > + virtio_vsock_skb_set_reply(skb);
>> > +
>> > trace_virtio_transport_alloc_pkt(src_cid, src_port,
>> > dst_cid, dst_port,
>> > len,
>> > @@ -91,85 +96,26 @@ virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
>> > info->op,
>> > info->flags);
>> >
>> > - return pkt;
>> > + return skb;
>> >
>> > out:
>> > - kfree(pkt->buf);
>> > -out_pkt:
>> > - kfree(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> > return NULL;
>> > }
>> >
>> > /* Packet capture */
>> > static struct sk_buff *virtio_transport_build_skb(void *opaque)
>> > {
>> > - struct virtio_vsock_pkt *pkt = opaque;
>> > - struct af_vsockmon_hdr *hdr;
>> > - struct sk_buff *skb;
>> > - size_t payload_len;
>> > - void *payload_buf;
>> > -
>> > - /* A packet could be split to fit the RX buffer, so we can
>> > retrieve
>> > - * the payload length from the header and the buffer pointer taking
>> > - * care of the offset in the original packet.
>> > - */
>> > - payload_len = le32_to_cpu(pkt->hdr.len);
>> > - payload_buf = pkt->buf + pkt->off;
>> > -
>> > - skb = alloc_skb(sizeof(*hdr) + sizeof(pkt->hdr) + payload_len,
>> > - GFP_ATOMIC);
>> > - if (!skb)
>> > - return NULL;
>> > -
>> > - hdr = skb_put(skb, sizeof(*hdr));
>> > -
>> > - /* pkt->hdr is little-endian so no need to byteswap here */
>> > - hdr->src_cid = pkt->hdr.src_cid;
>> > - hdr->src_port = pkt->hdr.src_port;
>> > - hdr->dst_cid = pkt->hdr.dst_cid;
>> > - hdr->dst_port = pkt->hdr.dst_port;
>> > -
>> > - hdr->transport = cpu_to_le16(AF_VSOCK_TRANSPORT_VIRTIO);
>> > - hdr->len = cpu_to_le16(sizeof(pkt->hdr));
>> > - memset(hdr->reserved, 0, sizeof(hdr->reserved));
>> > -
>> > - switch (le16_to_cpu(pkt->hdr.op)) {
>> > - case VIRTIO_VSOCK_OP_REQUEST:
>> > - case VIRTIO_VSOCK_OP_RESPONSE:
>> > - hdr->op = cpu_to_le16(AF_VSOCK_OP_CONNECT);
>> > - break;
>> > - case VIRTIO_VSOCK_OP_RST:
>> > - case VIRTIO_VSOCK_OP_SHUTDOWN:
>> > - hdr->op = cpu_to_le16(AF_VSOCK_OP_DISCONNECT);
>> > - break;
>> > - case VIRTIO_VSOCK_OP_RW:
>> > - hdr->op = cpu_to_le16(AF_VSOCK_OP_PAYLOAD);
>> > - break;
>> > - case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
>> > - case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
>> > - hdr->op = cpu_to_le16(AF_VSOCK_OP_CONTROL);
>> > - break;
>> > - default:
>> > - hdr->op = cpu_to_le16(AF_VSOCK_OP_UNKNOWN);
>> > - break;
>> > - }
>> > -
>> > - skb_put_data(skb, &pkt->hdr, sizeof(pkt->hdr));
>> > -
>> > - if (payload_len) {
>> > - skb_put_data(skb, payload_buf, payload_len);
>> > - }
>> > -
>> > - return skb;
>> > + return skb_copy(opaque, GFP_ATOMIC);
>>
>> I don't think we can make a simple copy, af_vsockmon_hdr is different from
>> virtio_vsock_hdr.
>>
>> Have you tried to see if wireshark, tcpdump works?
>>
>
>I'll give it a test. Seems like I overlooked that detail.

I'm pretty sure we have to keep this function (or part of it for header
conversion) because the headers are different. Since `af_vsockmon_hdr`
is part of UAPI, we have to keep it as it is.

>
>> > }
>> >
>> > -void virtio_transport_deliver_tap_pkt(struct virtio_vsock_pkt *pkt)
>> > +void virtio_transport_deliver_tap_pkt(struct sk_buff *skb)
>> > {
>> > - if (pkt->tap_delivered)
>> > + if (virtio_vsock_skb_tap_delivered(skb))
>> > return;
>> >
>> > - vsock_deliver_tap(virtio_transport_build_skb, pkt);
>> > - pkt->tap_delivered = true;
>> > + vsock_deliver_tap(virtio_transport_build_skb, skb);
>> > + virtio_vsock_skb_set_tap_delivered(skb);
>> > }
>> > EXPORT_SYMBOL_GPL(virtio_transport_deliver_tap_pkt);
>> >
>> > @@ -192,8 +138,8 @@ static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
>> > u32 src_cid, src_port, dst_cid, dst_port;
>> > const struct virtio_transport *t_ops;
>> > struct virtio_vsock_sock *vvs;
>> > - struct virtio_vsock_pkt *pkt;
>> > u32 pkt_len = info->pkt_len;
>> > + struct sk_buff *skb;
>> >
>> > info->type = virtio_transport_get_type(sk_vsock(vsk));
>> >
>> > @@ -224,42 +170,47 @@ static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
>> > if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
>> > return pkt_len;
>> >
>> > - pkt = virtio_transport_alloc_pkt(info, pkt_len,
>> > + skb = virtio_transport_alloc_skb(info, pkt_len,
>> > src_cid, src_port,
>> > dst_cid, dst_port);
>> > - if (!pkt) {
>> > + if (!skb) {
>> > virtio_transport_put_credit(vvs, pkt_len);
>> > return -ENOMEM;
>> > }
>> >
>> > - virtio_transport_inc_tx_pkt(vvs, pkt);
>> > + virtio_transport_inc_tx_pkt(vvs, skb);
>> >
>> > - return t_ops->send_pkt(pkt);
>> > + return t_ops->send_pkt(skb);
>> > }
>> >
>> > static bool virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > - if (vvs->rx_bytes + pkt->len > vvs->buf_alloc)
>> > + if (vvs->rx_bytes + skb->len > vvs->buf_alloc)
>> > return false;
>> >
>> > - vvs->rx_bytes += pkt->len;
>> > + vvs->rx_bytes += skb->len;
>> > return true;
>> > }
>> >
>> > static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > - vvs->rx_bytes -= pkt->len;
>> > - vvs->fwd_cnt += pkt->len;
>> > + int len;
>> > +
>> > + len = skb_headroom(skb) - sizeof(struct virtio_vsock_hdr) - skb->len;
>> > + vvs->rx_bytes -= len;
>> > + vvs->fwd_cnt += len;
>> > }
>> >
>> > -void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt)
>> > +void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > +
>> > spin_lock_bh(&vvs->rx_lock);
>> > vvs->last_fwd_cnt = vvs->fwd_cnt;
>> > - pkt->hdr.fwd_cnt = cpu_to_le32(vvs->fwd_cnt);
>> > - pkt->hdr.buf_alloc = cpu_to_le32(vvs->buf_alloc);
>> > + hdr->fwd_cnt = cpu_to_le32(vvs->fwd_cnt);
>> > + hdr->buf_alloc = cpu_to_le32(vvs->buf_alloc);
>> > spin_unlock_bh(&vvs->rx_lock);
>> > }
>> > EXPORT_SYMBOL_GPL(virtio_transport_inc_tx_pkt);
>> > @@ -303,29 +254,29 @@ virtio_transport_stream_do_peek(struct vsock_sock *vsk,
>> > size_t len)
>> > {
>> > struct virtio_vsock_sock *vvs = vsk->trans;
>> > - struct virtio_vsock_pkt *pkt;
>> > size_t bytes, total = 0, off;
>> > + struct sk_buff *skb, *tmp;
>> > int err = -EFAULT;
>> >
>> > spin_lock_bh(&vvs->rx_lock);
>> >
>> > - list_for_each_entry(pkt, &vvs->rx_queue, list) {
>> > - off = pkt->off;
>> > + skb_queue_walk_safe(&vvs->rx_queue, skb, tmp) {
>> > + off = 0;
>> >
>> > if (total == len)
>> > break;
>> >
>> > - while (total < len && off < pkt->len) {
>> > + while (total < len && off < skb->len) {
>> > bytes = len - total;
>> > - if (bytes > pkt->len - off)
>> > - bytes = pkt->len - off;
>> > + if (bytes > skb->len - off)
>> > + bytes = skb->len - off;
>> >
>> > /* sk_lock is held by caller so no one else can dequeue.
>> > * Unlock rx_lock since memcpy_to_msg() may sleep.
>> > */
>> > spin_unlock_bh(&vvs->rx_lock);
>> >
>> > - err = memcpy_to_msg(msg, pkt->buf + off, bytes);
>> > + err = memcpy_to_msg(msg, skb->data + off, bytes);
>> > if (err)
>> > goto out;
>> >
>> > @@ -352,37 +303,38 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
>> > size_t len)
>> > {
>> > struct virtio_vsock_sock *vvs = vsk->trans;
>> > - struct virtio_vsock_pkt *pkt;
>> > size_t bytes, total = 0;
>> > - u32 free_space;
>> > + struct sk_buff *skb;
>> > int err = -EFAULT;
>> > + u32 free_space;
>> >
>> > spin_lock_bh(&vvs->rx_lock);
>> > - while (total < len && !list_empty(&vvs->rx_queue)) {
>> > - pkt = list_first_entry(&vvs->rx_queue,
>> > - struct virtio_vsock_pkt, list);
>> > + while (total < len && !skb_queue_empty_lockless(&vvs->rx_queue)) {
>> > + skb = __skb_dequeue(&vvs->rx_queue);
>> >
>> > bytes = len - total;
>> > - if (bytes > pkt->len - pkt->off)
>> > - bytes = pkt->len - pkt->off;
>> > + if (bytes > skb->len)
>> > + bytes = skb->len;
>> >
>> > /* sk_lock is held by caller so no one else can dequeue.
>> > * Unlock rx_lock since memcpy_to_msg() may sleep.
>> > */
>> > spin_unlock_bh(&vvs->rx_lock);
>> >
>> > - err = memcpy_to_msg(msg, pkt->buf + pkt->off, bytes);
>> > + err = memcpy_to_msg(msg, skb->data, bytes);
>> > if (err)
>> > goto out;
>> >
>> > spin_lock_bh(&vvs->rx_lock);
>> >
>> > total += bytes;
>> > - pkt->off += bytes;
>> > - if (pkt->off == pkt->len) {
>> > - virtio_transport_dec_rx_pkt(vvs, pkt);
>> > - list_del(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > + skb_pull(skb, bytes);
>> > +
>> > + if (skb->len == 0) {
>> > + virtio_transport_dec_rx_pkt(vvs, skb);
>> > + virtio_vsock_consume_skb(skb);
>> > + } else {
>> > + __skb_queue_head(&vvs->rx_queue, skb);
>> > }
>> > }
>> >
>> > @@ -414,10 +366,10 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk,
>> > int flags)
>> > {
>> > struct virtio_vsock_sock *vvs = vsk->trans;
>> > - struct virtio_vsock_pkt *pkt;
>> > int dequeued_len = 0;
>> > size_t user_buf_len = msg_data_left(msg);
>> > bool msg_ready = false;
>> > + struct sk_buff *skb;
>> >
>> > spin_lock_bh(&vvs->rx_lock);
>> >
>> > @@ -427,13 +379,18 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk,
>> > }
>> >
>> > while (!msg_ready) {
>> > - pkt = list_first_entry(&vvs->rx_queue, struct virtio_vsock_pkt, list);
>> > + struct virtio_vsock_hdr *hdr;
>> > +
>> > + skb = __skb_dequeue(&vvs->rx_queue);
>> > + if (!skb)
>> > + break;
>> > + hdr = virtio_vsock_hdr(skb);
>> >
>> > if (dequeued_len >= 0) {
>> > size_t pkt_len;
>> > size_t bytes_to_copy;
>> >
>> > - pkt_len = (size_t)le32_to_cpu(pkt->hdr.len);
>> > + pkt_len = (size_t)le32_to_cpu(hdr->len);
>> > bytes_to_copy = min(user_buf_len, pkt_len);
>> >
>> > if (bytes_to_copy) {
>> > @@ -444,7 +401,7 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk,
>> > */
>> > spin_unlock_bh(&vvs->rx_lock);
>> >
>> > - err = memcpy_to_msg(msg, pkt->buf, bytes_to_copy);
>> > + err = memcpy_to_msg(msg, skb->data, bytes_to_copy);
>> > if (err) {
>> > /* Copy of message failed. Rest of
>> > * fragments will be freed without copy.
>> > @@ -452,6 +409,7 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk,
>> > dequeued_len = err;
>> > } else {
>> > user_buf_len -= bytes_to_copy;
>> > + skb_pull(skb, bytes_to_copy);
>> > }
>> >
>> > spin_lock_bh(&vvs->rx_lock);
>> > @@ -461,17 +419,16 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk,
>> > dequeued_len += pkt_len;
>> > }
>> >
>> > - if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOM) {
>> > + if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SEQ_EOM) {
>> > msg_ready = true;
>> > vvs->msg_count--;
>> >
>> > - if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOR)
>> > + if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SEQ_EOR)
>> > msg->msg_flags |= MSG_EOR;
>> > }
>> >
>> > - virtio_transport_dec_rx_pkt(vvs, pkt);
>> > - list_del(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_transport_dec_rx_pkt(vvs, skb);
>> > + virtio_vsock_kfree_skb(skb);
>> > }
>> >
>> > spin_unlock_bh(&vvs->rx_lock);
>> > @@ -609,7 +566,7 @@ int virtio_transport_do_socket_init(struct vsock_sock *vsk,
>> >
>> > spin_lock_init(&vvs->rx_lock);
>> > spin_lock_init(&vvs->tx_lock);
>> > - INIT_LIST_HEAD(&vvs->rx_queue);
>> > + skb_queue_head_init(&vvs->rx_queue);
>> >
>> > return 0;
>> > }
>> > @@ -806,16 +763,16 @@ void virtio_transport_destruct(struct vsock_sock *vsk)
>> > EXPORT_SYMBOL_GPL(virtio_transport_destruct);
>> >
>> > static int virtio_transport_reset(struct vsock_sock *vsk,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > struct virtio_vsock_pkt_info info = {
>> > .op = VIRTIO_VSOCK_OP_RST,
>> > - .reply = !!pkt,
>> > + .reply = !!skb,
>> > .vsk = vsk,
>> > };
>> >
>> > /* Send RST only if the original pkt is not a RST pkt */
>> > - if (pkt && le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
>> > + if (skb && le16_to_cpu(virtio_vsock_hdr(skb)->op) == VIRTIO_VSOCK_OP_RST)
>> > return 0;
>> >
>> > return virtio_transport_send_pkt_info(vsk, &info);
>> > @@ -825,29 +782,30 @@ static int virtio_transport_reset(struct vsock_sock *vsk,
>> > * attempt was made to connect to a socket that does not exist.
>> > */
>> > static int virtio_transport_reset_no_sock(const struct virtio_transport *t,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > - struct virtio_vsock_pkt *reply;
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct virtio_vsock_pkt_info info = {
>> > .op = VIRTIO_VSOCK_OP_RST,
>> > - .type = le16_to_cpu(pkt->hdr.type),
>> > + .type = le16_to_cpu(hdr->type),
>> > .reply = true,
>> > };
>> > + struct sk_buff *reply;
>> >
>> > /* Send RST only if the original pkt is not a RST pkt */
>> > - if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
>> > + if (le16_to_cpu(hdr->op) == VIRTIO_VSOCK_OP_RST)
>> > return 0;
>> >
>> > - reply = virtio_transport_alloc_pkt(&info, 0,
>> > - le64_to_cpu(pkt->hdr.dst_cid),
>> > - le32_to_cpu(pkt->hdr.dst_port),
>> > - le64_to_cpu(pkt->hdr.src_cid),
>> > - le32_to_cpu(pkt->hdr.src_port));
>> > + reply = virtio_transport_alloc_skb(&info, 0,
>> > + le64_to_cpu(hdr->dst_cid),
>> > + le32_to_cpu(hdr->dst_port),
>> > + le64_to_cpu(hdr->src_cid),
>> > + le32_to_cpu(hdr->src_port));
>> > if (!reply)
>> > return -ENOMEM;
>> >
>> > if (!t) {
>> > - virtio_transport_free_pkt(reply);
>> > + virtio_vsock_kfree_skb(reply);
>> > return -ENOTCONN;
>> > }
>> >
>> > @@ -858,16 +816,11 @@ static int virtio_transport_reset_no_sock(const struct virtio_transport *t,
>> > static void virtio_transport_remove_sock(struct vsock_sock *vsk)
>> > {
>> > struct virtio_vsock_sock *vvs = vsk->trans;
>> > - struct virtio_vsock_pkt *pkt, *tmp;
>> >
>> > /* We don't need to take rx_lock, as the socket is closing and we are
>> > * removing it.
>> > */
>> > - list_for_each_entry_safe(pkt, tmp, &vvs->rx_queue, list) {
>> > - list_del(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > - }
>> > -
>> > + virtio_vsock_skb_queue_purge(&vvs->rx_queue);
>> > vsock_remove_sock(vsk);
>> > }
>> >
>> > @@ -981,13 +934,14 @@ EXPORT_SYMBOL_GPL(virtio_transport_release);
>> >
>> > static int
>> > virtio_transport_recv_connecting(struct sock *sk,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct vsock_sock *vsk = vsock_sk(sk);
>> > - int err;
>> > int skerr;
>> > + int err;
>> >
>> > - switch (le16_to_cpu(pkt->hdr.op)) {
>> > + switch (le16_to_cpu(hdr->op)) {
>> > case VIRTIO_VSOCK_OP_RESPONSE:
>> > sk->sk_state = TCP_ESTABLISHED;
>> > sk->sk_socket->state = SS_CONNECTED;
>> > @@ -1008,7 +962,7 @@ virtio_transport_recv_connecting(struct sock *sk,
>> > return 0;
>> >
>> > destroy:
>> > - virtio_transport_reset(vsk, pkt);
>> > + virtio_transport_reset(vsk, skb);
>> > sk->sk_state = TCP_CLOSE;
>> > sk->sk_err = skerr;
>> > sk_error_report(sk);
>> > @@ -1017,34 +971,37 @@ virtio_transport_recv_connecting(struct sock *sk,
>> >
>> > static void
>> > virtio_transport_recv_enqueue(struct vsock_sock *vsk,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > struct virtio_vsock_sock *vvs = vsk->trans;
>> > bool can_enqueue, free_pkt = false;
>> > + struct virtio_vsock_hdr *hdr;
>> > + u32 len;
>> >
>> > - pkt->len = le32_to_cpu(pkt->hdr.len);
>> > - pkt->off = 0;
>> > + hdr = virtio_vsock_hdr(skb);
>> > + len = le32_to_cpu(hdr->len);
>> >
>> > spin_lock_bh(&vvs->rx_lock);
>> >
>> > - can_enqueue = virtio_transport_inc_rx_pkt(vvs, pkt);
>> > + can_enqueue = virtio_transport_inc_rx_pkt(vvs, skb);
>> > if (!can_enqueue) {
>> > free_pkt = true;
>> > goto out;
>> > }
>> >
>> > - if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOM)
>> > + if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SEQ_EOM)
>> > vvs->msg_count++;
>> >
>> > /* Try to copy small packets into the buffer of last packet queued,
>> > * to avoid wasting memory queueing the entire buffer with a small
>> > * payload.
>> > */
>> > - if (pkt->len <= GOOD_COPY_LEN && !list_empty(&vvs->rx_queue)) {
>> > - struct virtio_vsock_pkt *last_pkt;
>> > + if (len <= GOOD_COPY_LEN && !skb_queue_empty_lockless(&vvs->rx_queue)) {
>> > + struct virtio_vsock_hdr *last_hdr;
>> > + struct sk_buff *last_skb;
>> >
>> > - last_pkt = list_last_entry(&vvs->rx_queue,
>> > - struct virtio_vsock_pkt, list);
>> > + last_skb = skb_peek_tail(&vvs->rx_queue);
>> > + last_hdr = virtio_vsock_hdr(last_skb);
>> >
>> > /* If there is space in the last packet queued, we copy the
>> > * new packet in its buffer. We avoid this if the last packet
>> > @@ -1052,35 +1009,34 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk,
>> > * delimiter of SEQPACKET message, so 'pkt' is the first packet
>> > * of a new message.
>> > */
>> > - if ((pkt->len <= last_pkt->buf_len - last_pkt->len) &&
>> > - !(le32_to_cpu(last_pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOM)) {
>> > - memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
>> > - pkt->len);
>> > - last_pkt->len += pkt->len;
>> > + if (skb->len < skb_tailroom(last_skb) &&
>> > + !(le32_to_cpu(last_hdr->flags) & VIRTIO_VSOCK_SEQ_EOM)) {
>> > + memcpy(skb_put(last_skb, skb->len), skb->data, skb->len);
>> > free_pkt = true;
>> > - last_pkt->hdr.flags |= pkt->hdr.flags;
>> > + last_hdr->flags |= hdr->flags;
>> > goto out;
>> > }
>> > }
>> >
>> > - list_add_tail(&pkt->list, &vvs->rx_queue);
>> > + __skb_queue_tail(&vvs->rx_queue, skb);
>> >
>> > out:
>> > spin_unlock_bh(&vvs->rx_lock);
>> > if (free_pkt)
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> > }
>> >
>> > static int
>> > virtio_transport_recv_connected(struct sock *sk,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct vsock_sock *vsk = vsock_sk(sk);
>> > int err = 0;
>> >
>> > - switch (le16_to_cpu(pkt->hdr.op)) {
>> > + switch (le16_to_cpu(hdr->op)) {
>> > case VIRTIO_VSOCK_OP_RW:
>> > - virtio_transport_recv_enqueue(vsk, pkt);
>> > + virtio_transport_recv_enqueue(vsk, skb);
>> > vsock_data_ready(sk);
>> > return err;
>> > case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
>> > @@ -1090,18 +1046,17 @@ virtio_transport_recv_connected(struct sock *sk,
>> > sk->sk_write_space(sk);
>> > break;
>> > case VIRTIO_VSOCK_OP_SHUTDOWN:
>> > - if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_RCV)
>> > + if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SHUTDOWN_RCV)
>> > vsk->peer_shutdown |= RCV_SHUTDOWN;
>> > - if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_SEND)
>> > + if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SHUTDOWN_SEND)
>> > vsk->peer_shutdown |= SEND_SHUTDOWN;
>> > if (vsk->peer_shutdown == SHUTDOWN_MASK &&
>> > vsock_stream_has_data(vsk) <= 0 &&
>> > !sock_flag(sk, SOCK_DONE)) {
>> > (void)virtio_transport_reset(vsk, NULL);
>> > -
>> > virtio_transport_do_close(vsk, true);
>> > }
>> > - if (le32_to_cpu(pkt->hdr.flags))
>> > + if (le32_to_cpu(virtio_vsock_hdr(skb)->flags))
>> > sk->sk_state_change(sk);
>> > break;
>> > case VIRTIO_VSOCK_OP_RST:
>> > @@ -1112,28 +1067,30 @@ virtio_transport_recv_connected(struct sock *sk,
>> > break;
>> > }
>> >
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> > return err;
>> > }
>> >
>> > static void
>> > virtio_transport_recv_disconnecting(struct sock *sk,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct vsock_sock *vsk = vsock_sk(sk);
>> >
>> > - if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
>> > + if (le16_to_cpu(hdr->op) == VIRTIO_VSOCK_OP_RST)
>> > virtio_transport_do_close(vsk, true);
>> > }
>> >
>> > static int
>> > virtio_transport_send_response(struct vsock_sock *vsk,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct virtio_vsock_pkt_info info = {
>> > .op = VIRTIO_VSOCK_OP_RESPONSE,
>> > - .remote_cid = le64_to_cpu(pkt->hdr.src_cid),
>> > - .remote_port = le32_to_cpu(pkt->hdr.src_port),
>> > + .remote_cid = le64_to_cpu(hdr->src_cid),
>> > + .remote_port = le32_to_cpu(hdr->src_port),
>> > .reply = true,
>> > .vsk = vsk,
>> > };
>> > @@ -1142,8 +1099,9 @@ virtio_transport_send_response(struct vsock_sock *vsk,
>> > }
>> >
>> > static bool virtio_transport_space_update(struct sock *sk,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct vsock_sock *vsk = vsock_sk(sk);
>> > struct virtio_vsock_sock *vvs = vsk->trans;
>> > bool space_available;
>> > @@ -1158,8 +1116,8 @@ static bool virtio_transport_space_update(struct sock *sk,
>> >
>> > /* buf_alloc and fwd_cnt is always included in the hdr */
>> > spin_lock_bh(&vvs->tx_lock);
>> > - vvs->peer_buf_alloc = le32_to_cpu(pkt->hdr.buf_alloc);
>> > - vvs->peer_fwd_cnt = le32_to_cpu(pkt->hdr.fwd_cnt);
>> > + vvs->peer_buf_alloc = le32_to_cpu(hdr->buf_alloc);
>> > + vvs->peer_fwd_cnt = le32_to_cpu(hdr->fwd_cnt);
>> > space_available = virtio_transport_has_space(vsk);
>> > spin_unlock_bh(&vvs->tx_lock);
>> > return space_available;
>> > @@ -1167,27 +1125,28 @@ static bool virtio_transport_space_update(struct sock *sk,
>> >
>> > /* Handle server socket */
>> > static int
>> > -virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt,
>> > +virtio_transport_recv_listen(struct sock *sk, struct sk_buff *skb,
>> > struct virtio_transport *t)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct vsock_sock *vsk = vsock_sk(sk);
>> > struct vsock_sock *vchild;
>> > struct sock *child;
>> > int ret;
>> >
>> > - if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_REQUEST) {
>> > - virtio_transport_reset_no_sock(t, pkt);
>> > + if (le16_to_cpu(hdr->op) != VIRTIO_VSOCK_OP_REQUEST) {
>> > + virtio_transport_reset_no_sock(t, skb);
>> > return -EINVAL;
>> > }
>> >
>> > if (sk_acceptq_is_full(sk)) {
>> > - virtio_transport_reset_no_sock(t, pkt);
>> > + virtio_transport_reset_no_sock(t, skb);
>> > return -ENOMEM;
>> > }
>> >
>> > child = vsock_create_connected(sk);
>> > if (!child) {
>> > - virtio_transport_reset_no_sock(t, pkt);
>> > + virtio_transport_reset_no_sock(t, skb);
>> > return -ENOMEM;
>> > }
>> >
>> > @@ -1198,10 +1157,10 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt,
>> > child->sk_state = TCP_ESTABLISHED;
>> >
>> > vchild = vsock_sk(child);
>> > - vsock_addr_init(&vchild->local_addr, le64_to_cpu(pkt->hdr.dst_cid),
>> > - le32_to_cpu(pkt->hdr.dst_port));
>> > - vsock_addr_init(&vchild->remote_addr, le64_to_cpu(pkt->hdr.src_cid),
>> > - le32_to_cpu(pkt->hdr.src_port));
>> > + vsock_addr_init(&vchild->local_addr, le64_to_cpu(hdr->dst_cid),
>> > + le32_to_cpu(hdr->dst_port));
>> > + vsock_addr_init(&vchild->remote_addr, le64_to_cpu(hdr->src_cid),
>> > + le32_to_cpu(hdr->src_port));
>> >
>> > ret = vsock_assign_transport(vchild, vsk);
>> > /* Transport assigned (looking at remote_addr) must be the same
>> > @@ -1209,17 +1168,17 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt,
>> > */
>> > if (ret || vchild->transport != &t->transport) {
>> > release_sock(child);
>> > - virtio_transport_reset_no_sock(t, pkt);
>> > + virtio_transport_reset_no_sock(t, skb);
>> > sock_put(child);
>> > return ret;
>> > }
>> >
>> > - if (virtio_transport_space_update(child, pkt))
>> > + if (virtio_transport_space_update(child, skb))
>> > child->sk_write_space(child);
>> >
>> > vsock_insert_connected(vchild);
>> > vsock_enqueue_accept(sk, child);
>> > - virtio_transport_send_response(vchild, pkt);
>> > + virtio_transport_send_response(vchild, skb);
>> >
>> > release_sock(child);
>> >
>> > @@ -1237,29 +1196,30 @@ static bool virtio_transport_valid_type(u16 type)
>> > * lock.
>> > */
>> > void virtio_transport_recv_pkt(struct virtio_transport *t,
>> > - struct virtio_vsock_pkt *pkt)
>> > + struct sk_buff *skb)
>> > {
>> > + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
>> > struct sockaddr_vm src, dst;
>> > struct vsock_sock *vsk;
>> > struct sock *sk;
>> > bool space_available;
>> >
>> > - vsock_addr_init(&src, le64_to_cpu(pkt->hdr.src_cid),
>> > - le32_to_cpu(pkt->hdr.src_port));
>> > - vsock_addr_init(&dst, le64_to_cpu(pkt->hdr.dst_cid),
>> > - le32_to_cpu(pkt->hdr.dst_port));
>> > + vsock_addr_init(&src, le64_to_cpu(hdr->src_cid),
>> > + le32_to_cpu(hdr->src_port));
>> > + vsock_addr_init(&dst, le64_to_cpu(hdr->dst_cid),
>> > + le32_to_cpu(hdr->dst_port));
>> >
>> > trace_virtio_transport_recv_pkt(src.svm_cid, src.svm_port,
>> > dst.svm_cid, dst.svm_port,
>> > - le32_to_cpu(pkt->hdr.len),
>> > - le16_to_cpu(pkt->hdr.type),
>> > - le16_to_cpu(pkt->hdr.op),
>> > - le32_to_cpu(pkt->hdr.flags),
>> > - le32_to_cpu(pkt->hdr.buf_alloc),
>> > - le32_to_cpu(pkt->hdr.fwd_cnt));
>> > -
>> > - if (!virtio_transport_valid_type(le16_to_cpu(pkt->hdr.type))) {
>> > - (void)virtio_transport_reset_no_sock(t, pkt);
>> > + le32_to_cpu(hdr->len),
>> > + le16_to_cpu(hdr->type),
>> > + le16_to_cpu(hdr->op),
>> > + le32_to_cpu(hdr->flags),
>> > + le32_to_cpu(hdr->buf_alloc),
>> > + le32_to_cpu(hdr->fwd_cnt));
>> > +
>> > + if (!virtio_transport_valid_type(le16_to_cpu(hdr->type))) {
>> > + (void)virtio_transport_reset_no_sock(t, skb);
>> > goto free_pkt;
>> > }
>> >
>> > @@ -1270,13 +1230,13 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
>> > if (!sk) {
>> > sk = vsock_find_bound_socket(&dst);
>> > if (!sk) {
>> > - (void)virtio_transport_reset_no_sock(t, pkt);
>> > + (void)virtio_transport_reset_no_sock(t, skb);
>> > goto free_pkt;
>> > }
>> > }
>> >
>> > - if (virtio_transport_get_type(sk) != le16_to_cpu(pkt->hdr.type)) {
>> > - (void)virtio_transport_reset_no_sock(t, pkt);
>> > + if (virtio_transport_get_type(sk) != le16_to_cpu(hdr->type)) {
>> > + (void)virtio_transport_reset_no_sock(t, skb);
>> > sock_put(sk);
>> > goto free_pkt;
>> > }
>> > @@ -1287,13 +1247,13 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
>> >
>> > /* Check if sk has been closed before lock_sock */
>> > if (sock_flag(sk, SOCK_DONE)) {
>> > - (void)virtio_transport_reset_no_sock(t, pkt);
>> > + (void)virtio_transport_reset_no_sock(t, skb);
>> > release_sock(sk);
>> > sock_put(sk);
>> > goto free_pkt;
>> > }
>> >
>> > - space_available = virtio_transport_space_update(sk, pkt);
>> > + space_available = virtio_transport_space_update(sk, skb);
>> >
>> > /* Update CID in case it has changed after a transport reset event */
>> > if (vsk->local_addr.svm_cid != VMADDR_CID_ANY)
>> > @@ -1304,23 +1264,23 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
>> >
>> > switch (sk->sk_state) {
>> > case TCP_LISTEN:
>> > - virtio_transport_recv_listen(sk, pkt, t);
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_transport_recv_listen(sk, skb, t);
>> > + virtio_vsock_kfree_skb(skb);
>> > break;
>> > case TCP_SYN_SENT:
>> > - virtio_transport_recv_connecting(sk, pkt);
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_transport_recv_connecting(sk, skb);
>> > + virtio_vsock_kfree_skb(skb);
>> > break;
>> > case TCP_ESTABLISHED:
>> > - virtio_transport_recv_connected(sk, pkt);
>> > + virtio_transport_recv_connected(sk, skb);
>> > break;
>> > case TCP_CLOSING:
>> > - virtio_transport_recv_disconnecting(sk, pkt);
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_transport_recv_disconnecting(sk, skb);
>> > + virtio_vsock_kfree_skb(skb);
>> > break;
>> > default:
>> > - (void)virtio_transport_reset_no_sock(t, pkt);
>> > - virtio_transport_free_pkt(pkt);
>> > + (void)virtio_transport_reset_no_sock(t, skb);
>> > + virtio_vsock_kfree_skb(skb);
>> > break;
>> > }
>> >
>> > @@ -1333,16 +1293,42 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
>> > return;
>> >
>> > free_pkt:
>> > - virtio_transport_free_pkt(pkt);
>> > + virtio_vsock_kfree_skb(skb);
>> > }
>> > EXPORT_SYMBOL_GPL(virtio_transport_recv_pkt);
>> >
>> > -void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt)
>> > +/* Remove skbs found in a queue that have a vsk that matches.
>> > + *
>> > + * Each skb is freed.
>> > + *
>> > + * Returns the count of skbs that were reply packets.
>> > + */
>> > +int virtio_transport_purge_skbs(void *vsk, struct sk_buff_head *queue)
>> > {
>> > - kvfree(pkt->buf);
>> > - kfree(pkt);
>> > + struct sk_buff_head freeme;
>> > + struct sk_buff *skb, *tmp;
>> > + int cnt = 0;
>> > +
>> > + skb_queue_head_init(&freeme);
>> > +
>> > + spin_lock(&queue->lock);
>> > + skb_queue_walk_safe(queue, skb, tmp) {
>> > + if (vsock_sk(skb->sk) != vsk)
>> > + continue;
>> > +
>> > + __skb_unlink(skb, queue);
>> > + skb_queue_tail(&freeme, skb);
>> > +
>> > + if (virtio_vsock_skb_reply(skb))
>> > + cnt++;
>> > + }
>> > + spin_unlock(&queue->lock);
>> > +
>> > + virtio_vsock_skb_queue_purge(&freeme);
>> > +
>> > + return cnt;
>> > }
>> > -EXPORT_SYMBOL_GPL(virtio_transport_free_pkt);
>> > +EXPORT_SYMBOL_GPL(virtio_transport_purge_skbs);
>> >
>> > MODULE_LICENSE("GPL v2");
>> > MODULE_AUTHOR("Asias He");
>> > diff --git a/net/vmw_vsock/vsock_loopback.c b/net/vmw_vsock/vsock_loopback.c
>> > index 169a8cf65b39..e57394579146 100644
>> > --- a/net/vmw_vsock/vsock_loopback.c
>> > +++ b/net/vmw_vsock/vsock_loopback.c
>> > @@ -16,7 +16,7 @@ struct vsock_loopback {
>> > struct workqueue_struct *workqueue;
>> >
>> > spinlock_t pkt_list_lock; /* protects pkt_list */
>> > - struct list_head pkt_list;
>> > + struct sk_buff_head pkt_queue;
>> > struct work_struct pkt_work;
>> > };
>> >
>> > @@ -27,13 +27,13 @@ static u32 vsock_loopback_get_local_cid(void)
>> > return VMADDR_CID_LOCAL;
>> > }
>> >
>> > -static int vsock_loopback_send_pkt(struct virtio_vsock_pkt *pkt)
>> > +static int vsock_loopback_send_pkt(struct sk_buff *skb)
>> > {
>> > struct vsock_loopback *vsock = &the_vsock_loopback;
>> > - int len = pkt->len;
>> > + int len = skb->len;
>> >
>> > spin_lock_bh(&vsock->pkt_list_lock);
>> > - list_add_tail(&pkt->list, &vsock->pkt_list);
>> > + skb_queue_tail(&vsock->pkt_queue, skb);
>> > spin_unlock_bh(&vsock->pkt_list_lock);
>> >
>> > queue_work(vsock->workqueue, &vsock->pkt_work);
>> > @@ -44,21 +44,8 @@ static int vsock_loopback_send_pkt(struct virtio_vsock_pkt *pkt)
>> > static int vsock_loopback_cancel_pkt(struct vsock_sock *vsk)
>> > {
>> > struct vsock_loopback *vsock = &the_vsock_loopback;
>> > - struct virtio_vsock_pkt *pkt, *n;
>> > - LIST_HEAD(freeme);
>> >
>> > - spin_lock_bh(&vsock->pkt_list_lock);
>> > - list_for_each_entry_safe(pkt, n, &vsock->pkt_list, list) {
>> > - if (pkt->vsk != vsk)
>> > - continue;
>> > - list_move(&pkt->list, &freeme);
>> > - }
>> > - spin_unlock_bh(&vsock->pkt_list_lock);
>> > -
>> > - list_for_each_entry_safe(pkt, n, &freeme, list) {
>> > - list_del(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > - }
>> > + virtio_transport_purge_skbs(vsk, &vsock->pkt_queue);
>> >
>> > return 0;
>> > }
>> > @@ -121,20 +108,18 @@ static void vsock_loopback_work(struct work_struct *work)
>> > {
>> > struct vsock_loopback *vsock =
>> > container_of(work, struct vsock_loopback, pkt_work);
>> > - LIST_HEAD(pkts);
>> > + struct sk_buff_head pkts;
>> > + struct sk_buff *skb;
>> > +
>> > + skb_queue_head_init(&pkts);
>> >
>> > spin_lock_bh(&vsock->pkt_list_lock);
>> > - list_splice_init(&vsock->pkt_list, &pkts);
>> > + skb_queue_splice_init(&vsock->pkt_queue, &pkts);
>> > spin_unlock_bh(&vsock->pkt_list_lock);
>> >
>> > - while (!list_empty(&pkts)) {
>> > - struct virtio_vsock_pkt *pkt;
>> > -
>> > - pkt = list_first_entry(&pkts, struct virtio_vsock_pkt, list);
>> > - list_del_init(&pkt->list);
>> > -
>> > - virtio_transport_deliver_tap_pkt(pkt);
>> > - virtio_transport_recv_pkt(&loopback_transport, pkt);
>> > + while ((skb = skb_dequeue(&pkts))) {
>> > + virtio_transport_deliver_tap_pkt(skb);
>> > + virtio_transport_recv_pkt(&loopback_transport, skb);
>> > }
>> > }
>> >
>> > @@ -148,7 +133,7 @@ static int __init vsock_loopback_init(void)
>> > return -ENOMEM;
>> >
>> > spin_lock_init(&vsock->pkt_list_lock);
>> > - INIT_LIST_HEAD(&vsock->pkt_list);
>> > + skb_queue_head_init(&vsock->pkt_queue);
>> > INIT_WORK(&vsock->pkt_work, vsock_loopback_work);
>> >
>> > ret = vsock_core_register(&loopback_transport.transport,
>> > @@ -166,19 +151,13 @@ static int __init vsock_loopback_init(void)
>> > static void __exit vsock_loopback_exit(void)
>> > {
>> > struct vsock_loopback *vsock = &the_vsock_loopback;
>> > - struct virtio_vsock_pkt *pkt;
>> >
>> > vsock_core_unregister(&loopback_transport.transport);
>> >
>> > flush_work(&vsock->pkt_work);
>> >
>> > spin_lock_bh(&vsock->pkt_list_lock);
>> > - while (!list_empty(&vsock->pkt_list)) {
>> > - pkt = list_first_entry(&vsock->pkt_list,
>> > - struct virtio_vsock_pkt, list);
>> > - list_del(&pkt->list);
>> > - virtio_transport_free_pkt(pkt);
>> > - }
>> > + virtio_vsock_skb_queue_purge(&vsock->pkt_queue);
>> > spin_unlock_bh(&vsock->pkt_list_lock);
>> >
>> > destroy_workqueue(vsock->workqueue);
>> > --
>> > 2.20.1
>> >
>>
>>
>> Good job, I left some comments on things to be fixed, but I think we are
>> well on the way.
>>
>> Next nice step to have (not in this patch/series) is to move packet queuing
>> to the core and have all transports use skbuff (if they can).
>>
>> Thanks,
>> Stefano
>
>Thanks for the review!
>

You're welcome!

Have a nice weekend,
Stefano