Merge shared code that's necessary for mlx5 vdpa bits to build.

The branch itself includes a small number of patches and is also
independently merged by a couple of other trees.
That shouldn't cause any conflicts by itself.

Saeed Mahameed <saeedm@mellanox.com> says:

---

mlx5-next is a very small branch based on a very early rc that includes
mlx5 shared stuff between rdma and net-next, and now virtio as well.

---
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

IRQ of a vq is not expected to be changed in a DRIVER_OK ~ !DRIVER_OK
period for irq offloading purposes. Place this comment at the side of
bus ops get_vq_irq than in set_status in vhost_vdpa.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Link: https://lore.kernel.org/r/20200804102123.69978-1-lingshan.zhu@intel.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

Fix the comment of virtio_pci_find_capability() by adding missing comment
for the last parameter: bars.

Fixes: 59a5b0f7 ("virtio-pci: alloc only resources actually used.")
Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Link: https://lore.kernel.org/r/1596455545-43556-1-git-send-email-wang.yi59@zte.com.cnSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>

If failed to connect, there is no need to start consumer nor
producer.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-7-lingshan.zhu@intel.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

This commit implemented vdpa_config_ops.get_vq_irq() in ifcvf,
and initialized vq irq to -EINVAL. So that ifcvf can report
irq number of a vq, or -EINVAL if the vq is not assigned an
irq number.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-6-lingshan.zhu@intel.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

This patch introduce a set of functions for setup/unsetup
and update irq offloading respectively by register/unregister
and re-register the irq_bypass_producer.

With these functions, this commit can setup/unsetup
irq offloading through setting DRIVER_OK/!DRIVER_OK, and
update irq offloading through SET_VRING_CALL.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-5-lingshan.zhu@intel.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

This commit adds a new function get_vq_irq() in struct
vdpa_config_ops, which will return the irq number of a
virtqueue.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-4-lingshan.zhu@intel.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

vDPA devices has dedicated backed hardware like
passthrough-ed devices. Then it is possible to setup irq
offloading to vCPU for vDPA devices. Thus this patch tries to
manipulated assigned device counters by
kvm_arch_start/end_assignment() in irqbypass manager, so that
assigned devices could be detected in update_pi_irte()

We will increase/decrease the assigned device counter in kvm/x86.
Both vDPA and VFIO would go through this code path.

Only X86 uses these counters and kvm_arch_start/end_assignment(),
so this code path only affect x86 for now.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-3-lingshan.zhu@intel.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

This commit introduces struct vhost_vring_call which replaced
raw struct eventfd_ctx *call_ctx in struct vhost_virtqueue.
Besides eventfd_ctx, it contains a spin lock and an
irq_bypass_producer in its structure.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Suggested-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731065533.4144-2-lingshan.zhu@intel.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

Make use of the flex_array_size() helper to calculate the size of a
flexible array member within an enclosing structure.

This helper offers defense-in-depth against potential integer
overflows, while at the same time makes it explicitly clear that
we are dealing with a flexible array member.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200731130956.GA30525@embeddedorSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

Iommu iotlb can be accessed by different cores for performing IO using
multiple virt queues. Add a spinlock to synchronize iotlb accesses.

This could be easily reproduced when using more than 1 pktgen threads
to inject traffic to vdpa simulator.

Fixes: 2c53d0f6("vdpasim: vDPA device simulator")
Cc: stable@vger.kernel.org
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200731073822.13326-1-jasowang@redhat.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

We used to have a per device feature whitelist to filter out the
unsupported virtio features. But this seems unnecessary since:

- the main idea behind feature whitelist is to block control vq
  feature until we finalize the control virtqueue API. But the current
  vhost-vDPA uAPI is sufficient to support control virtqueue. For
  device that has hardware control virtqueue, the vDPA device driver
  can just setup the hardware virtqueue and let userspace to use
  hardware virtqueue directly. For device that doesn't have a control
  virtqueue, the vDPA device driver need to use e.g vringh to emulate
  a software control virtqueue.
- we don't do it in virtio-vDPA driver

So remove this limitation.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200720085043.16485-1-jasowang@redhat.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

The loop may exist if vq->broken is true,
virtqueue_get_buf_ctx_packed or virtqueue_get_buf_ctx_split
will return NULL, so virtnet_poll will reschedule napi to
receive packet, it will lead cpu usage(si) to 100%.

call trace as below:
virtnet_poll
	virtnet_receive
		virtqueue_get_buf_ctx
			virtqueue_get_buf_ctx_packed
			virtqueue_get_buf_ctx_split
	virtqueue_napi_complete
		virtqueue_poll           //return true
		virtqueue_napi_schedule //it will reschedule napi

to fix this, return false if vq is broken in virtqueue_poll.
Signed-off-by: Mao Wenan <wenan.mao@linux.alibaba.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/1596354249-96204-1-git-send-email-wenan.mao@linux.alibaba.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>

Speed and duplex config fields depend on VIRTIO_NET_F_SPEED_DUPLEX
which being 63>31 depends on VIRTIO_F_VERSION_1.

Accordingly, use LE accessors for these fields.
Reported-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

All drivers now use virtio_cread/write_le for LE config
space fields. Drop LE option from virtio_cread/write, only leaving
the option to access transitional fields.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Virtio iommu is modern-only. Use LE accessors for config space.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Virtio mem is modern-only. Use LE accessors for config space.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Virtgpu is modern-only. Use LE accessors for config space.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Virtio pmem is modern-only. Use LE accessors for config space.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Virtio crypto is modern-only. Use LE accessors for config space.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Virtio fs is modern-only. Use LE accessors for config space.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Virtio input is modern-only. Use LE accessors for config space.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Balloon is LE, it's cleaner to access it as such directly.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Mirrors virtio_cread_feature but for LE fields.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Tag config space fields as having virtio endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

To be used by modern code, as well as to handle LE only fields such as
balloon.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

_Generic version allowed __uXX types but that is no longer necessary:

Transitional devices should all use __virtioXX types (and __leXX for
fields not present in the legacy devices).
Modern ones should use __leXX.
_uXX type would be a bug.
Let's prevent that.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Min compiler version has been raised, so that's ok now.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Use vars of the correct type instead of casting.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

VDPA sim accesses config space as native endian - this is
wrong since it's a modern device and actually uses LE.

It only supports modern guests so we could punt and
just force LE, but let's use the full virtio APIs since people
tend to copy/paste code, and this is not data path anyway.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

We normally expect vdpa to use the modern interface.
However for consistency, let's use same APIs as vhost
for legacy guests.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

For new helpers handling legacy features to be effective,
vhost needs to invoke them. Tie them in.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Some legacy guests just assume features are 0 after reset.
We detect that config space is accessed before features are
set and set features to 0 automatically.
Note: some legacy guests might not even access config space, if this is
reported in the field we might need to catch a kick to handle these.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

mlxbf-tmfifo accesses config space using native types -
which works for it since the legacy virtio native types.

This will break if it ever needs to support modern virtio,
so with new tags previously introduced for virtio net config,
sparse now warns for this in drivers.

Since this is a legacy only device, fix it up using
virtio_legacy_is_little_endian for now.

No functional changes.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>

Transitional devices should all use __virtioXX types (and __leXX for
fields not present in legacy devices).
Modern ones should use __leXX.
_uXX type would be a bug.
Let's prevent that.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Tag config space fields as having virtio endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>

Since this is a modern-only device,
tag config space fields as having little endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>

Tag config space fields as having virtio endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Since this is a modern-only device,
tag config space fields as having little endian-ness.

TODO: check other uses of __virtioXX types in this header,
should probably be __leXX.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>

Since this is a modern-only device,
tag config space fields as having little endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>