[net PATCH v5 0/6] virtio_net XDP fixes and adjust_header support

[John Fastabend <john.fastabend@gmail.com>]

This has a fix to handle small buffer free logic correctly and then
also adds adjust head support.

I pushed adjust head at net (even though its rc3) to avoid having
to push another exception case into virtio_net to catch if the
program uses adjust_head and then block it. If there are any strong
objections to this we can push it at net-next and use a patch from
Jakub to add the exception handling but then user space has to deal
with it either via try/fail logic or via kernel version checks. Granted
we already have some cases that need to be configured to enable XDP
but I don't see any reason to have yet another one when we can fix it
now vs delaying a kernel version.


v2: fix spelling error, convert unsigned -> unsigned int
v3: v2 git crashed during send so retrying sorry for the noise
v4: changed layout of rtnl_lock fixes (Stephen)
    moved reset logic into virtio core with new patch (MST)
    fixed up linearize and some code cleanup (Jason)

    Otherwise did some generic code cleanup so might be a bit
    cleaner this time at least that is the hope.
v5: fixed rtnl_lock issue (DaveM)

    In order to fix rtnl_lock issue and also to address Jason's
    comment questioning the need for a generic virtio_device_reset
    routine I exported some virtio core routines and then wrote
    virtio_net reset routine. This is the cleanest solution I
    came up with today and I do not at this time have any need
    for a more generic reset. If folks don't like this I could
    revert back to v3 variant but Stephen pointed out that the
    pattern used there is also not ideal.

Thanks for the review.

---

John Fastabend (6):
      virtio_net: use dev_kfree_skb for small buffer XDP receive
      virtio_net: wrap rtnl_lock in test for calling with lock already held
      virtio_net: factor out xdp handler for readability
      virtio_net: remove duplicate queue pair binding in XDP
      virtio_net: refactor freeze/restore logic into virtnet reset logic
      virtio_net: XDP support for adjust_head


 drivers/net/virtio_net.c |  332 ++++++++++++++++++++++++++++++----------------
 drivers/virtio/virtio.c  |   42 +++---
 include/linux/virtio.h   |    4 +
 3 files changed, 247 insertions(+), 131 deletions(-)