linux.git/drivers/s390/virtio, branch v5.3.2

virtio/s390: fix race on airq_areas[]

2019-07-26T11:36:18+00:00

The access to airq_areas was racy ever since the adapter interrupts got
introduced to virtio-ccw, but since commit 39c7dcb15892 ("virtio/s390:
make airq summary indicators DMA") this became an issue in practice as
well. Namely before that commit the airq_info that got overwritten was
still functional. After that commit however the two infos share a
summary_indicator, which aggravates the situation. Which means
auto-online mechanism occasionally hangs the boot with virtio_blk.

Signed-off-by: Halil Pasic 
Reported-by: Marc Hartmayer 
Reviewed-by: Cornelia Huck 
Cc: stable@vger.kernel.org
Fixes: 96b14536d935 ("virtio-ccw: virtio-ccw adapter interrupt support.")
Signed-off-by: Heiko Carstens

virtio/s390: make airq summary indicators DMA

2019-06-15T10:25:41+00:00

The hypervisor needs to interact with the summary indicators, so these
need to be DMA memory as well (at least for protected virtualization
guests).

Signed-off-by: Halil Pasic 
Reviewed-by: Cornelia Huck 
Reviewed-by: Michael Mueller 
Tested-by: Michael Mueller 
Signed-off-by: Heiko Carstens

virtio/s390: use DMA memory for ccw I/O and classic notifiers

2019-06-15T10:25:37+00:00

Before virtio-ccw could get away with not using DMA API for the pieces of
memory it does ccw I/O with. With protected virtualization this has to
change, since the hypervisor needs to read and sometimes also write these
pieces of memory.

The hypervisor is supposed to poke the classic notifiers, if these are
used, out of band with regards to ccw I/O. So these need to be allocated
as DMA memory (which is shared memory for protected virtualization
guests).

Let us factor out everything from struct virtio_ccw_device that needs to
be DMA memory in a satellite that is allocated as such.

Note: The control blocks of I/O instructions do not need to be shared.
These are marshalled by the ultravisor.

Signed-off-by: Halil Pasic 
Reviewed-by: Pierre Morel 
Reviewed-by: Cornelia Huck 
Reviewed-by: Michael Mueller 
Tested-by: Michael Mueller 
Signed-off-by: Heiko Carstens

virtio/s390: add indirection to indicators access

2019-06-15T10:25:33+00:00

This will come in handy soon when we pull out the indicators from
virtio_ccw_device to a memory area that is shared with the hypervisor
(in particular for protected virtualization guests).

Signed-off-by: Halil Pasic 
Reviewed-by: Pierre Morel 
Reviewed-by: Cornelia Huck 
Reviewed-by: Michael Mueller 
Tested-by: Michael Mueller 
Signed-off-by: Heiko Carstens

virtio/s390: use cacheline aligned airq bit vectors

2019-06-15T10:25:28+00:00

The flag AIRQ_IV_CACHELINE was recently added to airq_iv_create(). Let
us use it! We actually wanted the vector to span a cacheline all along.

Signed-off-by: Halil Pasic 
Reviewed-by: Christian Borntraeger 
Reviewed-by: Cornelia Huck 
Reviewed-by: Michael Mueller 
Tested-by: Michael Mueller 
Signed-off-by: Heiko Carstens

s390/cio: add basic protected virtualization support

2019-06-15T10:25:00+00:00

As virtio-ccw devices are channel devices, we need to use the
dma area within the common I/O layer for any communication with
the hypervisor.

Note that we do not need to use that area for control blocks
directly referenced by instructions, e.g. the orb.

It handles neither QDIO in the common code, nor any device type specific
stuff (like channel programs constructed by the DASD driver).

An interesting side effect is that virtio structures are now going to
get allocated in 31 bit addressable storage.

Signed-off-by: Halil Pasic 
Reviewed-by: Sebastian Ott 
Reviewed-by: Cornelia Huck 
Reviewed-by: Michael Mueller 
Tested-by: Michael Mueller 
Signed-off-by: Heiko Carstens

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2019-05-14T21:12:59+00:00

Pull virtio updates from Michael Tsirkin:

 - enable packed ring support for s390

 - several fixes

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio/s390: enable packed ring
  virtio/s390: DMA support for virtio-ccw
  virtio/s390: use vring_create_virtqueue
  virtio/virtio_ring: do some comment fixes
  vhost-scsi: remove incorrect memory barrier
  tools/virtio/ringtest: Remove bogus definition of BUG_ON()
  virtio_ring: Fix potential mem leak in virtqueue_add_indirect_packed

virtio/s390: enable packed ring

2019-05-12T17:11:36+00:00

Nothing precludes to accepting  VIRTIO_F_RING_PACKED any more.

Signed-off-by: Halil Pasic 
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Cornelia Huck

virtio/s390: DMA support for virtio-ccw

2019-05-12T17:11:36+00:00

Currently virtio-ccw devices do not work if the device has
VIRTIO_F_IOMMU_PLATFORM. In future we do want to support DMA API with
virtio-ccw.

Let us do the plumbing, so the feature VIRTIO_F_IOMMU_PLATFORM works
with virtio-ccw.

Let us also switch from legacy avail/used accessors to the DMA aware
ones (even if it isn't strictly necessary), and remove the legacy
accessors (we were the last users).

Signed-off-by: Halil Pasic 
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Cornelia Huck

virtio/s390: use vring_create_virtqueue

2019-05-12T17:11:36+00:00

The commit 2a2d1382fe9d ("virtio: Add improved queue allocation API")
establishes a new way of allocating virtqueues (as a part of the effort
that taught DMA to virtio rings).

In the future we will want virtio-ccw to use the DMA API as well.

Let us switch from the legacy method of allocating virtqueues to
vring_create_virtqueue() as the first step into that direction.

Signed-off-by: Halil Pasic 
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Cornelia Huck