kernel.git/drivers/net/virtio_net.c, branch linux-5.8.y

virtio-net: don't disable guest csum when disable LRO

2020-10-14T09:55:54Z

[ Upstream commit 1a03b8a35a957f9f38ecb8a97443b7380bbf6a8b ] Open vSwitch and Linux bridge will disable LRO of the interface when this interface added to them. Now when disable the LRO, the virtio-net csum is disable too. That drops the forwarding performance. Fixes: a02e8964eaf9 ("virtio-net: ethtool configurable LRO") Cc: Michael S. Tsirkin Cc: Jason Wang Cc: Willem de Bruijn Signed-off-by: Tonghao Zhang Acked-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

xdp: Rename convert_to_xdp_frame in xdp_convert_buff_to_frame

2020-06-01T22:02:53Z

In order to use standard 'xdp' prefix, rename convert_to_xdp_frame utility routine in xdp_convert_buff_to_frame and replace all the occurrences Signed-off-by: Lorenzo Bianconi Signed-off-by: Alexei Starovoitov Acked-by: Jesper Dangaard Brouer Link: https://lore.kernel.org/bpf/6344f739be0d1a08ab2b9607584c4d5478c8c083.1590698295.git.lorenzo@kernel.org

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-05-15T20:48:59Z

Move the bpf verifier trace check into the new switch statement in HEAD. Resolve the overlapping changes in hinic, where bug fixes overlap the addition of VF support. Signed-off-by: David S. Miller

virtio_net: Add XDP frame size in two code paths

2020-05-15T04:21:55Z

The virtio_net driver is running inside the guest-OS. There are two XDP receive code-paths in virtio_net, namely receive_small() and receive_mergeable(). The receive_big() function does not support XDP. In receive_small() the frame size is available in buflen. The buffer backing these frames are allocated in add_recvbuf_small() with same size, except for the headroom, but tailroom have reserved room for skb_shared_info. The headroom is encoded in ctx pointer as a value. In receive_mergeable() the frame size is more dynamic. There are two basic cases: (1) buffer size is based on a exponentially weighted moving average (see DECLARE_EWMA) of packet length. Or (2) in case virtnet_get_headroom() have any headroom then buffer size is PAGE_SIZE. The ctx pointer is this time used for encoding two values; the buffer len "truesize" and headroom. In case (1) if the rx buffer size is underestimated, the packet will have been split over more buffers (num_buf info in virtio_net_hdr_mrg_rxbuf placed in top of buffer area). If that happens the XDP path does a xdp_linearize_page operation. V3: Adjust frame_sz in receive_mergeable() case, spotted by Jason Wang. The code is really hard to follow, so some hints to reviewers. The receive_mergeable() case gets frames that were allocated in add_recvbuf_mergeable() which uses headroom=virtnet_get_headroom(), and 'buf' ptr is advanced this headroom. The headroom can only be 0 or VIRTIO_XDP_HEADROOM, as virtnet_get_headroom is really simple: static unsigned int virtnet_get_headroom(struct virtnet_info *vi) { return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0; } As frame_sz is an offset size from xdp.data_hard_start, reviewers should notice how this is calculated in receive_mergeable(): int offset = buf - page_address(page); [...] data = page_address(xdp_page) + offset; xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len; The calculated offset will always be VIRTIO_XDP_HEADROOM when reaching this code. Thus, xdp.data_hard_start will be page-start address plus vi->hdr_len. Given this xdp.frame_sz need to be reduced with vi->hdr_len size. IMHO a followup patch should cleanup this code to make it easier to maintain and understand, but it is outside the scope of this patchset. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Alexei Starovoitov Acked-by: Michael S. Tsirkin Acked-by: Jason Wang Link: https://lore.kernel.org/bpf/158945344436.97035.9445115070189151680.stgit@firesoul

virtio_net: fix lockdep warning on 32 bit

2020-05-07T14:57:21Z

When we fill up a receive VQ, try_fill_recv currently tries to count kicks using a 64 bit stats counter. Turns out, on a 32 bit kernel that uses a seqcount. sequence counts are "lock" constructs where you need to make sure that writers are serialized. In turn, this means that we mustn't run two try_fill_recv concurrently. Which of course we don't. We do run try_fill_recv sometimes from a softirq napi context, and sometimes from a fully preemptible context, but the later always runs with napi disabled. However, when it comes to the seqcount, lockdep is trying to enforce the rule that the same lock isn't accessed from preemptible and softirq context - it doesn't know about napi being enabled/disabled. This causes a false-positive warning: WARNING: inconsistent lock state ... inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. As a work around, shut down the warning by switching to u64_stats_update_begin_irqsave - that works by disabling interrupts on 32 bit only, is a NOP on 64 bit. Reported-by: Thomas Gleixner Suggested-by: Eric Dumazet Signed-off-by: Michael S. Tsirkin Signed-off-by: David S. Miller

virtio_net: reject unsupported coalescing params

2020-03-05T20:12:35Z

Set ethtool_ops->supported_coalesce_params to let the core reject unsupported coalescing parameters. This driver correctly rejects all unsupported parameters. As a side effect of these changes the error code for unsupported params changes from EINVAL to EOPNOTSUPP. v2: correctly handle rx-frames (and adjust the commit msg) v3: adjust commit message for new error code and member name Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

net/ethtool: Introduce link_ksettings API for virtual network devices

2020-03-01T05:48:55Z

With the ethtool_virtdev_set_link_ksettings function in core/ethtool.c, ibmveth, netvsc, and virtio now use the core's helper function. Funtionality changes that pertain to ibmveth driver include: 1. Changed the initial hardcoded link speed to 1GB. 2. Added support for allowing a user to change the reported link speed via ethtool. Functionality changes to the netvsc driver include: 1. When netvsc_get_link_ksettings is called, it will defer to the VF device if it exists to pull accelerated networking values, otherwise pull default or user-defined values. 2. Similarly, if netvsc_set_link_ksettings called and a VF device exists, the real values of speed and duplex are changed. Signed-off-by: Cris Forno Signed-off-by: David S. Miller

virtio_net: Add XDP meta data support

2020-02-25T21:50:55Z

Implement support for transferring XDP meta data into skb for virtio_net driver; before calling into the program, xdp.data_meta points to xdp.data, where on program return with pass verdict, we call into skb_metadata_set(). Tested with the script at https://github.com/higebu/virtio_net-xdp-metadata-test. Signed-off-by: Yuya Kusakabe Signed-off-by: Daniel Borkmann Acked-by: Jason Wang Acked-by: Michael S. Tsirkin Link: https://lore.kernel.org/bpf/20200225033212.437563-2-yuya.kusakabe@gmail.com

virtio_net: Keep vnet header zeroed if XDP is loaded for small buffer

2020-02-25T21:50:55Z

We do not want to care about the vnet header in receive_small() if XDP is loaded, since we can not know whether or not the packet is modified by XDP. Fixes: f6b10209b90d ("virtio-net: switch to use build_skb() for small buffer") Signed-off-by: Yuya Kusakabe Signed-off-by: Daniel Borkmann Acked-by: Jason Wang Acked-by: Michael S. Tsirkin Link: https://lore.kernel.org/bpf/20200225033212.437563-1-yuya.kusakabe@gmail.com

bpf, xdp: virtio_net use access ptr macro for xdp enable check

2020-01-27T10:16:25Z

virtio_net currently relies on rcu critical section to access the xdp program in its xdp_xmit handler. However, the pointer to the xdp program is only used to do a NULL pointer comparison to determine if xdp is enabled or not. Use rcu_access_pointer() instead of rcu_dereference() to reflect this. Then later when we drop rcu_read critical section virtio_net will not need in special handling. Signed-off-by: John Fastabend Signed-off-by: Daniel Borkmann Acked-by: Jesper Dangaard Brouer Link: https://lore.kernel.org/bpf/1580084042-11598-3-git-send-email-john.fastabend@gmail.com