Commit Graph

153 Commits

Author SHA1 Message Date
Michael S. Tsirkin
b4b9862b53 virtio: Fix no interrupt when not creating msi controller
For ARM virt machine, if we use virt-2.7 which will not create ITS node,
the virtio-net can not recieve interrupts so it can't get ip address
through dhcp.
This fixes commit 83d768b(virtio: set ISR on dataplane notifications).

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Paolo Bonzini
97cd965c07 virtio: use VRingMemoryRegionCaches for avail and used rings
The virtio-net change is necessary because it uses virtqueue_fill
and virtqueue_flush instead of the more convenient virtqueue_push.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Paolo Bonzini
ca0176ad83 virtio: check for vring setup in virtio_queue_update_used_idx
If the vring has not been set up, it is not necessary for vring_used_idx
to do anything (as is already the case when the caller is virtio_load).
This is harmless for now, but it will be a problem when the
MemoryRegionCache has not been set up.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Paolo Bonzini
991976f751 virtio: use VRingMemoryRegionCaches for descriptor ring
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Paolo Bonzini
c611c76417 virtio: add MemoryListener to cache ring translations
The cached translations are RCU-protected to allow efficient use
when processing virtqueues.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Paolo Bonzini
5eba0404b9 virtio: use MemoryRegionCache to access descriptors
For now, the cache is created on every virtqueue_pop.  Later on,
direct descriptors will be able to reuse it.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Paolo Bonzini
9796d0ac8f virtio: use address_space_map/unmap to access descriptors
This makes little difference, but it makes the code change smaller
for the next patch that introduces MemoryRegionCache.  This is
because map/unmap are similar to MemoryRegionCache init/destroy.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Fam Zheng
0793169870 virtio: Report real progress in VQ aio poll handler
In virtio_queue_host_notifier_aio_poll, not all "!virtio_queue_empty()"
cases are making true progress.

Currently the offending one is virtio-scsi event queue, whose handler
does nothing if no event is pending. As a result aio_poll() will spin on
the "non-empty" VQ and take 100% host CPU.

Fix this by reporting actual progress from virtio queue aio handlers.

Reported-by: Ed Swierk <eswierk@skyportsystems.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Tested-by: Ed Swierk <eswierk@skyportsystems.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Paolo Bonzini
c25d97c4ff virtio: make virtio_should_notify static
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-01 03:37:18 +02:00
Jianjun Duan
2c21ee769e migration: extend VMStateInfo
Current migration code cannot handle some data structures such as
QTAILQ in qemu/queue.h. Here we extend the signatures of put/get
in VMStateInfo so that customized handling is supported. put now
will return int type.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com>
Message-Id: <1484852453-12728-2-git-send-email-duanj@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-01-24 17:54:47 +00:00
Peter Maydell
598cf1c805 * QOM interface fix (Eduardo)
* RTC fixes (Gaohuai, Igor)
 * Memory leak fixes (Li Qiang, me)
 * Ctrl-a b regression (Marc-André)
 * Stubs cleanups and fixes (Leif, me)
 * hxtool tweak (me)
 * HAX support (Vincent)
 * QemuThread, exec.c and SCSI fixes (Roman, Xinhua, me)
 * PC_COMPAT_2_8 fix (Marcelo)
 * stronger bitmap assertions (Peter)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQExBAABCAAbBQJYggc9FBxwYm9uemluaUByZWRoYXQuY29tAAoJEL/70l94x66D
 5pMH/092iVHw1la8VmphQd8W7hkCHckvVbwaEJ+n4BP8MjeUNmYFJX+op9Qlpqfe
 ekYqQgK69v2UwuofVK2gqS+Y2EyFHivTESk5pS3SM3lTewV1fzCM/HVG3pTxV/ol
 V+eBnp+shrfNG3Eg7YThTqx4LkDUp24Pd3HJVblQZMVpqGzL2xUuUQzSf8F/eeQJ
 xO61pm0ovpCY5MCg3kPLx8GIkPAmcXo5jhMCTz5aLnQW6TO/mwx271a4UE2RTLZ7
 cFjNhxdGSzlnn2RwId4HVYWGU42taW6mpa8NX1hVVUXa1A2qlAfi5N/WLaH0aGYR
 J5ZTIaXdPUBx2SrUmd8udj4a818=
 =H5BQ
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* QOM interface fix (Eduardo)
* RTC fixes (Gaohuai, Igor)
* Memory leak fixes (Li Qiang, me)
* Ctrl-a b regression (Marc-André)
* Stubs cleanups and fixes (Leif, me)
* hxtool tweak (me)
* HAX support (Vincent)
* QemuThread, exec.c and SCSI fixes (Roman, Xinhua, me)
* PC_COMPAT_2_8 fix (Marcelo)
* stronger bitmap assertions (Peter)

# gpg: Signature made Fri 20 Jan 2017 12:49:01 GMT
# gpg:                using RSA key 0xBFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream: (35 commits)
  pc.h: move x-mach-use-reliable-get-clock compat entry to PC_COMPAT_2_8
  bitmap: assert that start and nr are non negative
  Revert "win32: don't run subprocess tests on Mingw32 platform"
  hax: add Darwin support
  Plumb the HAXM-based hardware acceleration support
  target/i386: Add Intel HAX files
  kvm: move cpu synchronization code
  KVM: PPC: eliminate unnecessary duplicate constants
  ramblock-notifier: new
  char: fix ctrl-a b not working
  exec: Add missing rcu_read_unlock
  x86: ioapic: fix fail migration when irqchip=split
  x86: ioapic: dump version for "info ioapic"
  x86: ioapic: add traces for ioapic
  hxtool: emit Texinfo headings as @subsection
  qemu-thread: fix qemu_thread_set_name() race in qemu_thread_create()
  serial: fix memory leak in serial exit
  scsi-block: fix direction of BYTCHK test for VERIFY commands
  pc: fix crash in rtc_set_memory() if initial cpu is marked as hotplugged
  acpi: filter based on CONFIG_ACPI_X86 rather than TARGET
  ...

# Conflicts:
#	include/hw/i386/pc.h
2017-01-20 16:42:07 +00:00
Peter Maydell
d1c82f7cc3 First set of s390x patches for 2.9:
- rework of the zpci code, giving us proper multibus support
 - introduction of the 2.9 machine
 - fixes and improvements
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJYgdReAAoJEN7Pa5PG8C+vDggP/i3eviyb2mFlnIiwazlAfBuw
 Uc6vBFDh/WWMthpzHl4PF+yujM3XbuvUN3VejdnqWLQ1PYq2p3n7rHNlR2XlBovu
 f8l2LpPZGsj1VtAr1QGBj5ipOmRs3qydXY7EDCKORbKuPeor1VW7TbeaKbfpvpZM
 rZHWMlV1UGA6kxM/B+zd9+kxBM3IYnHy3o+Gaq+cfuKyc0VRWRJmalqonjkR7EZj
 InaIyOtGonpPTlMD1GTbM71Wx/NnCugYUEX1Eq4yHX4DV15rM3B83LgTJu72txzr
 ObJmzT3XU2DKwtzo87Y6cWJ3GoxQQbwgiU6VL+l8JVtrzGfllpUdcdInQjSqxXp2
 OW8NuV6Ie02YOrczBXbBAv46PKmoLTf63hvsC4f6nNLa2O6FqxAXzYGKtOpvgOq5
 j1Q6VyzAb/vbyyW2lyMice4XJXGMxitaMGxvJG0lq/iscRpNdpz6E+dgkzO7lieF
 +ETpDsGd5miMdsAUqmIREjBCCjOzOGpC4WX0mg8Te8LmR3Rt8WYIgWuowMvbq2iG
 /qmv9a8ea2XqB+/g2ta+YqS9cPChsPJSN03Q0bo1244DMwBKuVwyXNsC9lRIkiHJ
 4b1Msoseohv9D4ghU8q6gSOU+T5nxLRT1TWBByqhkONU1C4UyKHEblop/c1oHE5k
 UZtiaQvyWFhVU4QtXeE8
 =fzmu
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20170120-v2' into staging

First set of s390x patches for 2.9:
- rework of the zpci code, giving us proper multibus support
- introduction of the 2.9 machine
- fixes and improvements

# gpg: Signature made Fri 20 Jan 2017 09:11:58 GMT
# gpg:                using RSA key 0xDECF6B93C6F02FAF
# gpg: Good signature from "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* remotes/cohuck/tags/s390x-20170120-v2:
  virtio-ccw: fix ring sizing
  s390x/pci: merge msix init functions
  s390x/pci: handle PCIBridge bus number
  s390x/pci: use hashtable to look up zpci via fh
  s390x/pci: PCI multibus bridge handling
  s390x/pci: optimize calling s390_get_phb()
  s390x/pci: change the device array to a list
  s390x/pci: dynamically allocate iommu
  s390x/pci: make S390PCIIOMMU inherit Object
  s390x/kvm: use kvm_gsi_routing_enabled in flic
  s390x: add compat machine for 2.9
  s390x: remove double compat statement

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-01-20 15:53:58 +00:00
Michael S. Tsirkin
8c797e758a virtio-ccw: fix ring sizing
Current code seems to assume ring size is
always decreased but this is not required by spec:
what spec says is just that size can not exceed
the maximum. Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <1484256243-1982-1-git-send-email-mst@redhat.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-20 10:02:02 +01:00
Michael S. Tsirkin
6bdc21c050 virtio: fix up max size checks
Coverity reports that ARRAY_SIZE(elem->out_sg) (and all the others too)
is wrong because elem->out_sg is a pointer.

However, the check is not in the right place and the max_size argument
of virtqueue_map_iovec can be removed.  The check on in_num/out_num
should be moved to qemu_get_virtqueue_element instead, before the call
to virtqueue_alloc_element.

Cc: qemu-stable@nongnu.org
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes: 3724650db0 ("virtio: introduce virtqueue_alloc_element")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-19 23:00:31 +02:00
Stefan Hajnoczi
1448c133e1 virtio: disable notifications again after poll succeeded
While AioContext is in polling mode virtqueue notifications are not
necessary.  Some device virtqueue handlers enable notifications.  Make
sure they stay disabled to avoid unnecessary vmexits.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Richard Henderson <rth@twiddle.net>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-18 22:59:53 +02:00
Stefan Hajnoczi
332fa82d09 Revert "virtio: turn vq->notification into a nested counter"
This reverts commit aff8fd18f1.

Both virtio-net and virtio-crypto do not balance
virtio_queue_set_notification() enable and disable calls.  This makes
the notifications_disabled counter unreliable and Doug Goldstein
reported the following assertion failure:

  #3  0x00007ffff44d1c62 in __GI___assert_fail (
      assertion=assertion@entry=0x555555ae8e8a "vq->notification_disabled > 0",
      file=file@entry=0x555555ae89c0 "/home/doug/work/qemu/hw/virtio/virtio.c",
      line=line@entry=215,
      function=function@entry=0x555555ae9630 <__PRETTY_FUNCTION__.43707>
      "virtio_queue_set_notification") at assert.c:101
  #4  0x00005555557f25d6 in virtio_queue_set_notification (vq=0x55555666aa90,
      enable=enable@entry=1) at /home/doug/work/qemu/hw/virtio/virtio.c:215
  #5  0x00005555557dc311 in virtio_net_has_buffers (q=<optimized out>,
      q=<optimized out>, bufsize=102)
      at /home/doug/work/qemu/hw/net/virtio-net.c:1008
  #6  virtio_net_receive (nc=<optimized out>, buf=0x555557386b88 "", size=102)
      at /home/doug/work/qemu/hw/net/virtio-net.c:1148
  #7  0x00005555559cad33 in nc_sendv_compat (flags=<optimized out>, iovcnt=1,
      iov=0x7fffead746d0, nc=0x55555788b340) at net/net.c:705
  #8  qemu_deliver_packet_iov (sender=<optimized out>, flags=<optimized out>,
      iov=0x7fffead746d0, iovcnt=1, opaque=0x55555788b340) at net/net.c:732
  #9  0x00005555559cd929 in qemu_net_queue_deliver (size=<optimized out>,
      data=<optimized out>, flags=<optimized out>, sender=<optimized out>,
      queue=0x55555788b550) at net/queue.c:164
  #10 qemu_net_queue_flush (queue=0x55555788b550) at net/queue.c:261

This patch is safe to revert since it's just an optimization for
virtqueue polling.  The next patch will improve the situation again
without resorting to nesting.

Reported-by: Doug Goldstein <cardoe@cardoe.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Richard Henderson <rth@twiddle.net>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-18 22:59:53 +02:00
Paolo Bonzini
d6da1e9eca event_notifier: cleanups around event_notifier_set_handler
Remove the useless is_external argument.  Since the iohandler
AioContext is never used for block devices, aio_disable_external
is never called on it.  This lets us remove stubs/iohandler.c.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-16 17:52:35 +01:00
Yuri Benditovich
54e17709ac virtio: Introduce virtqueue_drop_all procedure
Add procedure for fast drop of queued packets, acting like
pop and push without mapping the buffers into memory.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10 07:02:53 +02:00
Yuri Benditovich
312d3b3534 net: Add virtio queue interface to update used index from vring state
Bring virtio queue to correct internal  state for host-to-guest
operations when vhost is temporary stopped.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10 07:02:53 +02:00
Halil Pasic
e66bcc4081 virtio: fix vq->inuse recalc after migr
Correct recalculation of vq->inuse after migration for the corner case
where the avail_idx has already wrapped but used_idx not yet.

Also change the type of the VirtQueue.inuse to unsigned int. This is
done to be consistent with other members representing sizes (VRing.num),
and because C99 guarantees max ring size < UINT_MAX but does not
guarantee max ring size < INT_MAX.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Fixes: bccdef6b ("virtio: recalculate vq->inuse after migration")
CC: qemu-stable@nongnu.org
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-10 07:02:52 +02:00
Jason Wang
8607f5c307 virtio: convert to use DMA api
Currently, all virtio devices bypass IOMMU completely. This is because
address_space_memory is assumed and used during DMA emulation. This
patch converts the virtio core API to use DMA API. This idea is

- introducing a new transport specific helper to query the dma address
  space. (only pci version is implemented).
- query and use this address space during virtio device guest memory
  accessing when iommu platform (VIRTIO_F_IOMMU_PLATFORM) was enabled
  for this device.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10 05:56:58 +02:00
Stefan Hajnoczi
a7c8215e3b virtio: disable virtqueue notifications during polling
This is a performance optimization to eliminate vmexits during polling.
It also avoids spurious ioeventfd processing after polling ends.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20161201192652.9509-12-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-03 16:38:50 +00:00
Stefan Hajnoczi
aff8fd18f1 virtio: turn vq->notification into a nested counter
Polling should disable virtqueue notifications but that requires nested
virtio_queue_set_notification() calls.  Turn vq->notification into a
counter so it is possible to do nesting.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20161201192652.9509-10-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-03 16:38:49 +00:00
Stefan Hajnoczi
0062ea0fd6 virtio: poll virtqueues for new buffers
Add an AioContext poll handler to detect new virtqueue buffers without
waiting for a guest->host notification.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20161201192652.9509-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-03 16:38:48 +00:00
Stefan Hajnoczi
f6a51c84cd aio: add AioPollFn and io_poll() interface
The new AioPollFn io_poll() argument to aio_set_fd_handler() and
aio_set_event_handler() is used in the next patch.

Keep this code change separate due to the number of files it touches.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20161201192652.9509-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-03 16:38:48 +00:00
Paolo Bonzini
83d768b564 virtio: set ISR on dataplane notifications
Dataplane has been omitting forever the step of setting ISR when
an interrupt is raised.  This caused little breakage, because the
specification actually says that ISR may not be updated in MSI mode.

Some versions of the Windows drivers however didn't clear MSI mode
correctly, and proceeded using polling mode (using ISR, not the used
ring index!) for crashdump and hibernation.  If it were just crashdump
and hibernation it would not be a big deal, but recent releases of
Windows do not really shut down, but rather log out and hibernate to
make the next startup faster.  Hence, this manifested as a more serious
hang during shutdown with e.g. Windows 8.1 and virtio-win 1.8.0 RPMs.
Newer versions fixed this, while older versions do not use MSI at all.

The failure has always been there for virtio dataplane, but it became
visible after commits 9ffe337 ("virtio-blk: always use dataplane path
if ioeventfd is active", 2016-10-30) and ad07cd6 ("virtio-scsi: always
use dataplane path if ioeventfd is active", 2016-10-30) made virtio-blk
and virtio-scsi always use the dataplane code under KVM.  The good news
therefore is that it was not a bug in the patches---they were doing
exactly what they were meant for, i.e. shake out remaining dataplane bugs.

The fix is not hard, so it's worth arranging for the broken drivers.
The virtio_should_notify+event_notifier_set pair that is common to
virtio-blk and virtio-scsi dataplane is replaced with a new public
function virtio_notify_irqfd that also sets ISR.  The irqfd emulation
code now need not set ISR anymore, so virtio_irq is removed.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-11-18 17:29:25 +02:00
Paolo Bonzini
0687c37c5e virtio: access ISR atomically
This will be needed once dataplane will be able to set it outside
the big QEMU lock.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-11-18 17:29:25 +02:00
Paolo Bonzini
310837de6c virtio: introduce grab/release_ioeventfd to fix vhost
Following the recent refactoring of virtio notifiers [1], more specifically
the patch ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to
start/stop ioeventfd") that uses virtio_bus_set_host_notifier [2]
by default, core virtio code requires 'ioeventfd_started' to be set
to true/false when the host notifiers are configured.

When vhost is stopped and started, however, there is a stop followed by
another start. Since ioeventfd_started was never set to true, the 'stop'
operation triggered by virtio_bus_set_host_notifier() will not result
in a call to virtio_pci_ioeventfd_assign(assign=false). This leaves
the memory regions with stale notifiers and results on the next start
triggering the following assertion:

  kvm_mem_ioeventfd_add: error adding ioeventfd: File exists
  Aborted

This patch reintroduces (hopefully in a cleaner way) the concept
that was present with ioeventfd_disabled before the refactoring.
When ioeventfd_grabbed>0, ioeventfd_started tracks whether ioeventfd
should be enabled or not, but ioeventfd is actually not started at
all until vhost releases the host notifiers.

[1] http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg07748.html
[2] http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg07760.html

Reported-by: Felipe Franciosi <felipe@nutanix.com>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Fixes: ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to start/stop ioeventfd")
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-11-18 17:29:25 +02:00
Greg Kurz
435346d748 virtio: drop virtio_queue_get_ring_{size,addr}()
These are not used anymore.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-11-15 17:20:38 +02:00
Michael S. Tsirkin
9b706dbbbb virtio: allow per-device-class legacy features
Legacy features are those that transitional devices only
expose on the legacy interface.
Allow different ones per device class.

Cc: qemu-stable@nongnu.org # dependency for the next patch
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-11-15 17:20:36 +02:00
Ladi Prosek
bf91bd2792 virtio: make virtqueue_alloc_element static
The function does not fully initialize the returned VirtQueueElement and should
be used only internally from the virtio module.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-11-15 17:20:36 +02:00
Ladi Prosek
27e57efe32 virtio: rename virtqueue_discard to virtqueue_unpop
The function undoes the effect of virtqueue_pop and doesn't do anything
destructive or irreversible so virtqueue_unpop is a more fitting name.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-11-15 17:20:36 +02:00
Paolo Bonzini
fa283a4a8b virtio: inline virtio_queue_set_host_notifier_fd_handler
Of the three possible parameter combinations for
virtio_queue_set_host_notifier_fd_handler:

- assign=true/set_handler=true is only called from
  virtio_device_start_ioeventfd

- assign=false/set_handler=false is called from
  set_host_notifier_internal but it only does something when
  reached from virtio_device_stop_ioeventfd_impl; otherwise
  there is no EventNotifier set on qemu_get_aio_context().

- assign=true/set_handler=false is called from
  set_host_notifier_internal, but it is not doing anything:
  with the new start_ioeventfd and stop_ioeventfd methods,
  there is never an EventNotifier set on qemu_get_aio_context()
  at this point.  This is enforced by the assertion in
  virtio_bus_set_host_notifier.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30 20:06:21 +02:00
Paolo Bonzini
ed08a2a0ba virtio: use virtio_bus_set_host_notifier to start/stop ioeventfd
ioeventfd_disabled was the only reason for the default
implementation of virtio_device_start_ioeventfd not to use
virtio_bus_set_host_notifier.  This is now fixed, and the sole entry
point to set up ioeventfd can be virtio_bus_set_host_notifier.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30 20:06:21 +02:00
Paolo Bonzini
6019f3b966 virtio: remove set_handler argument from set_host_notifier_internal
Make virtio_device_start_ioeventfd_impl use the same logic as
dataplane to set up the host notifier.  This removes the need
for the set_handler argument in set_host_notifier_internal.

This is a first step towards using virtio_bus_set_host_notifier
as the sole entry point to set up ioeventfds.  At least now
the functions have the same interface, but they still differ
in that virtio_bus_set_host_notifier sets ioeventfd_disabled.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30 20:06:20 +02:00
Paolo Bonzini
f1ac6a5522 Revert "virtio: Introduce virtio_add_queue_aio"
This reverts commit 872dd82c83.
virtio_add_queue_aio is unused.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30 20:06:20 +02:00
Paolo Bonzini
8e93cef14e virtio: introduce virtio_device_ioeventfd_enabled
This will be used to forbid iothread configuration when the
proxy does not allow using ioeventfd.  To simplify the implementation,
change the direction of the ioeventfd_disabled callback too.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30 19:51:32 +02:00
Paolo Bonzini
ff4c07df67 virtio: add start_ioeventfd and stop_ioeventfd to VirtioDeviceClass
Allow customization of the start and stop of ioeventfd.  This will
allow direct start of dataplane without passing through the default
ioeventfd handlers, which in turn allows using the dataplane logic
instead of virtio_add_queue_aio.  It will also enable some code
simplification, because the sole entry point to ioeventfd setup
will be virtio_bus_set_host_notifier.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30 19:51:32 +02:00
Dr. David Alan Gilbert
ea43e25987 virtio/migration: Add VMStateDescription to VirtioDeviceClass
Provide a vmsd pointer for VirtIO devices to use instead of the
load/save methods.

We'll eventually kill off the load/save methods.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30 19:51:31 +02:00
Halil Pasic
5705653ff8 virtio: cleanup VMSTATE_VIRTIO_DEVICE
Now all the usages of the old version of VMSTATE_VIRTIO_DEVICE are gone,
so we can get rid of the conditionals, and the old macro.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 02:21:43 +03:00
Halil Pasic
1a665855d7 virtio: prepare change VMSTATE_VIRTIO_DEVICE macro
In most cases the functions passed to VMSTATE_VIRTIO_DEVICE
only call the virtio_load and virtio_save wrappers. Some include some
pre- and post- massaging too. The massaging is better expressed
as such in the VMStateDescription.

Let us prepare for changing the semantic of the VMSTATE_VIRTIO_DEVICE
macro so that it is more similar to the other VMSTATE_*_DEVICE macros
in a sense that it is a field definition.

The preprocessor conditionals are going to be removed as soon as
every usage is converted to the new semantic.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 02:21:42 +03:00
Stefan Hajnoczi
2640d2a5ff virtio: add virtio_detach_element()
During device reset or similar situations a VirtQueueElement needs to be
freed without pushing it onto the used ring or rewinding the virtqueue.
Extract a new function to do this.

Later patches add virtio_detach_element() calls to existing device so
that scatter-gather lists are unmapped and vq->inuse goes back to zero
during device reset.  Currently some devices don't bother and simply
call g_free(elem) which is not a clean way to throw away a
VirtQueueElement.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 01:16:58 +03:00
Stefan Hajnoczi
fb1131b674 virtio: handle virtqueue_get_head() errors
Stop processing the vring if virtqueue_get_head() fetches an
out-of-bounds head index.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23 19:03:56 +03:00
Stefan Hajnoczi
4355c1abca virtio: handle virtqueue_num_heads() errors
If the avail ring index is bogus virtqueue_num_heads() must return
-EINVAL.

The only caller is virtqueue_get_avail_bytes().  Return saying no bytes
are available when virtqueue_num_heads() fails.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23 19:03:56 +03:00
Stefan Hajnoczi
412e0e81b1 virtio: handle virtqueue_read_next_desc() errors
Stop processing the vring if an avail ring index is invalid.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23 19:03:56 +03:00
Stefan Hajnoczi
b1c7c07f2d virtio: use unsigned int for virtqueue_get_avail_bytes() index
The virtio code uses int, unsigned int, and uint16_t for virtqueue
indices.  The uint16_t is used for the low-level descriptor layout in
virtio_ring.h while code that isn't concerned with descriptor layout can
use unsigned int.

Use of int is problematic because it can result in signed/unsigned
comparison and incompatible int*/unsigned int* pointer types.

Make the virtqueue_get_avail_bytes() 'i' variable unsigned int.  This
eliminates the need to introduce casts and modify code further in the
patches that follow.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23 19:03:56 +03:00
Stefan Hajnoczi
d65abf85e7 virtio: handle virtqueue_get_avail_bytes() errors
If the vring is invalid, tell the caller no bytes are available and mark
the device broken.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23 19:03:56 +03:00
Stefan Hajnoczi
ec55da1924 virtio: handle virtqueue_map_desc() errors
Errors can occur during virtqueue_pop(), especially in
virtqueue_map_desc().  In order to handle this we must unmap iov[]
before returning NULL.  The caller will consider the virtqueue empty and
the virtio_error() call will have marked the device broken.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-09-23 19:03:55 +03:00
Stefan Hajnoczi
791b1daf72 virtio: migrate vdev->broken flag
Send a subsection if the vdev->broken flag is set.  This allows live
migration of broken virtio devices.

The subsection is only sent if vdev->broken has been set.  In most cases
the flag will be clear and no subsection will be sent.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23 19:03:55 +03:00
Stefan Hajnoczi
f5ed36635d virtio: stop virtqueue processing if device is broken
QEMU prints an error message and exits when the device enters an invalid
state.  Terminating the process is heavy-handed.  The guest may still be
able to function even if there is a bug in a virtio guest driver.

Moreover, exiting is a bug in nested virtualization where a nested guest
could DoS other nested guests by killing a pass-through virtio device.
I don't think this configuration is possible today but it is likely in
the future.

If the broken flag is set, do not process virtqueues or write back used
descriptors.  The broken flag can be cleared again by resetting the
device.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23 19:03:55 +03:00