netvsc_vf_xmit() / dev_queue_xmit() will call VF NIC’s ndo_select_queue
or netdev_pick_tx() again. They will use skb_get_rx_queue() to get the
queue number, so the “skb->queue_mapping - 1” will be used. This may
cause the last queue of VF not been used.

Use skb_record_rx_queue() here, so that the skb_get_rx_queue() called
later will get the correct queue number, and VF will be able to use
all queues.

Fixes: b3bf5666a510 ("hv_netvsc: defer queue selection to VF")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When using vf_ops->ndo_select_queue, the number of queues of VF is
usually bigger than the synthetic NIC. This condition may happen
often.
Remove "unlikely" from the comparison of ndev->real_num_tx_queues.

Fixes: b3bf5666a510 ("hv_netvsc: defer queue selection to VF")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If the accelerated networking SRIOV VF device has lost carrier
use the synthetic network device which is available as backup
path. This is a rare case since if VF link goes down, normally
the VMBus device will also loose external connectivity as well.
But if the communication is between two VM's on the same host
the VMBus device will still work.

Reported-by: "Shah, Ashish N" <ashish.n.shah@intel.com>
Fixes: 0c195567a8f6 ("netvsc: transparent VF management")
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Now that BPF program/link management is centralized in generic net_device
code, kernel code never queries program id from drivers, so
XDP_QUERY_PROG/XDP_QUERY_PROG_HW commands are unnecessary.

This patch removes all the implementations of those commands in kernel, along
the xdp_attachment_query().

This patch was compile-tested on allyesconfig.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200722064603.3350758-10-andriin@fb.com

An imbalanced TX indirection table causes netvsc to have low
performance. This table is created and managed during runtime. To help
better diagnose performance issues caused by imbalanced tables, it needs
make TX indirection tables visible.

Because TX indirection table is driver specified information, so
display it via ethtool register dump.

Signed-off-by: Chi Song <chisong@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Vlan tagged packets are getting dropped when used with DPDK that uses
the AF_PACKET interface on a hyperV guest.

The packet layer uses the tpacket interface to communicate the vlans
information to the upper layers. On Rx path, these drivers can read the
vlan info from the tpacket header but on the Tx path, this information
is still within the packet frame and requires the paravirtual drivers to
push this back into the NDIS header which is then used by the host OS to
form the packet.

This transition from the packet frame to NDIS header is currently missing
hence causing the host OS to drop the all vlan tagged packets sent by
the drivers that use AF_PACKET (ETH_P_ALL) such as DPDK.

Here is an overview of the changes in the vlan header in the packet path:

The RX path (userspace handles everything):
  1. RX VLAN packet is stripped by HOST OS and placed in NDIS header
  2. Guest Kernel RX hv_netvsc packets and moves VLAN info from NDIS
     header into kernel SKB
  3. Kernel shares packets with user space application with PACKET_MMAP.
     The SKB VLAN info is copied to tpacket layer and indication set
     TP_STATUS_VLAN_VALID.
  4. The user space application will re-insert the VLAN info into the frame

The TX path:
  1. The user space application has the VLAN info in the frame.
  2. Guest kernel gets packets from the application with PACKET_MMAP.
  3. The kernel later sends the frame to the hv_netvsc driver. The only way
     to send VLANs is when the SKB is setup & the VLAN is stripped from the
     frame.
  4. TX VLAN is re-inserted by HOST OS based on the NDIS header. If it sees
     a VLAN in the frame the packet is dropped.

Cc: xe-linux-external@cisco.com
Cc: Sriram Krishnan <srirakr2@cisco.com>
Signed-off-by: Sriram Krishnan <srirakr2@cisco.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking updates from David Miller:

 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
    Augusto von Dentz.

 2) Add GSO partial support to igc, from Sasha Neftin.

 3) Several cleanups and improvements to r8169 from Heiner Kallweit.

 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
    device self-test. From Andrew Lunn.

 5) Start moving away from custom driver versions, use the globally
    defined kernel version instead, from Leon Romanovsky.

 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.

 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.

 8) Add sriov and vf support to hinic, from Luo bin.

 9) Support Media Redundancy Protocol (MRP) in the bridging code, from
    Horatiu Vultur.

10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.

11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
    Dubroca. Also add ipv6 support for espintcp.

12) Lots of ReST conversions of the networking documentation, from Mauro
    Carvalho Chehab.

13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
    from Doug Berger.

14) Allow to dump cgroup id and filter by it in inet_diag code, from
    Dmitry Yakunin.

15) Add infrastructure to export netlink attribute policies to
    userspace, from Johannes Berg.

16) Several optimizations to sch_fq scheduler, from Eric Dumazet.

17) Fallback to the default qdisc if qdisc init fails because otherwise
    a packet scheduler init failure will make a device inoperative. From
    Jesper Dangaard Brouer.

18) Several RISCV bpf jit optimizations, from Luke Nelson.

19) Correct the return type of the ->ndo_start_xmit() method in several
    drivers, it's netdev_tx_t but many drivers were using
    'int'. From Yunjian Wang.

20) Add an ethtool interface for PHY master/slave config, from Oleksij
    Rempel.

21) Add BPF iterators, from Yonghang Song.

22) Add cable test infrastructure, including ethool interfaces, from
    Andrew Lunn. Marvell PHY driver is the first to support this
    facility.

23) Remove zero-length arrays all over, from Gustavo A. R. Silva.

24) Calculate and maintain an explicit frame size in XDP, from Jesper
    Dangaard Brouer.

25) Add CAP_BPF, from Alexei Starovoitov.

26) Support terse dumps in the packet scheduler, from Vlad Buslov.

27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.

28) Add devm_register_netdev(), from Bartosz Golaszewski.

29) Minimize qdisc resets, from Cong Wang.

30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
    eliminate set_fs/get_fs calls. From Christoph Hellwig.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
  selftests: net: ip_defrag: ignore EPERM
  net_failover: fixed rollback in net_failover_open()
  Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
  Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
  vmxnet3: allow rx flow hash ops only when rss is enabled
  hinic: add set_channels ethtool_ops support
  selftests/bpf: Add a default $(CXX) value
  tools/bpf: Don't use $(COMPILE.c)
  bpf, selftests: Use bpf_probe_read_kernel
  s390/bpf: Use bcr 0,%0 as tail call nop filler
  s390/bpf: Maintain 8-byte stack alignment
  selftests/bpf: Fix verifier test
  selftests/bpf: Fix sample_cnt shared between two threads
  bpf, selftests: Adapt cls_redirect to call csum_level helper
  bpf: Add csum_level helper for fixing up csum levels
  bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
  sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
  crypto/chtls: IPv6 support for inline TLS
  Crypto/chcr: Fixes a coccinile check error
  Crypto/chcr: Fixes compilations warnings
  ...

Pull hyper-v updates from Wei Liu:

 - a series from Andrea to support channel reassignment

 - a series from Vitaly to clean up Vmbus message handling

 - a series from Michael to clean up and augment hyperv-tlfs.h

 - patches from Andy to clean up GUID usage in Hyper-V code

 - a few other misc patches

* tag 'hyperv-next-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (29 commits)
  Drivers: hv: vmbus: Resolve more races involving init_vp_index()
  Drivers: hv: vmbus: Resolve race between init_vp_index() and CPU hotplug
  vmbus: Replace zero-length array with flexible-array
  Driver: hv: vmbus: drop a no long applicable comment
  hyper-v: Switch to use UUID types directly
  hyper-v: Replace open-coded variant of %*phN specifier
  hyper-v: Supply GUID pointer to printf() like functions
  hyper-v: Use UUID API for exporting the GUID (part 2)
  asm-generic/hyperv: Add definitions for Get/SetVpRegister hypercalls
  x86/hyperv: Split hyperv-tlfs.h into arch dependent and independent files
  x86/hyperv: Remove HV_PROCESSOR_POWER_STATE #defines
  KVM: x86: hyperv: Remove duplicate definitions of Reference TSC Page
  drivers: hv: remove redundant assignment to pointer primary_channel
  scsi: storvsc: Re-init stor_chns when a channel interrupt is re-assigned
  Drivers: hv: vmbus: Introduce the CHANNELMSG_MODIFYCHANNEL message type
  Drivers: hv: vmbus: Synchronize init_vp_index() vs. CPU hotplug
  Drivers: hv: vmbus: Remove the unused HV_LOCALIZED channel affinity logic
  PCI: hv: Prepare hv_compose_msi_msg() for the VMBus-channel-interrupt-to-vCPU reassignment functionality
  Drivers: hv: vmbus: Use a spin lock for synchronizing channel scheduling vs. channel removal
  hv_utils: Always execute the fcopy and vss callbacks in a tasklet
  ...

There are no users of MEM_TYPE_ZERO_COPY. Remove all corresponding
code, including the "handle" member of struct xdp_buff.

rfc->v1: Fixed spelling in commit message. (Björn)

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200520192103.355233-13-bjorn.topel@gmail.com

The hyperv NIC driver does memory allocation and copy even without XDP.
In XDP mode it will allocate a new page for each packet and copy over
the payload, before invoking the XDP BPF-prog.

The positive thing it that its easy to determine the xdp.frame_sz.

The XDP implementation for hv_netvsc transparently passes xdp_prog
to the associated VF NIC. Many of the Azure VMs are using SRIOV, so
majority of the data are actually processed directly on the VF driver's XDP
path. So the overhead of the synthetic data path (hv_netvsc) is minimal.

Then XDP is enabled on this driver, XDP_PASS and XDP_TX will create the
SKB via build_skb (based on the newly allocated page). Now using XDP
frame_sz this will provide more skb_tailroom, which netstack can use for
SKB coalescing (e.g tcp_try_coalesce -> skb_try_coalesce).

V3: Adjust patch desc to be more positive.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Link: https://lore.kernel.org/bpf/158945339857.97035.10212138582505736163.stgit@firesoul