Commit graph

274 commits

Author SHA1 Message Date
Rusty Russell
5b40a7daf5 virtio: don't set VIRTIO_CONFIG_S_DRIVER_OK twice.
I noticed this with the console device.  It's not *wrong*, just a bit
weird.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-17 16:19:29 +10:30
Rusty Russell
7abb568dbb virtio_pci: use 16-bit accessor for queue_enable.
Since PCI is little endian, 8-bit access might work, but the spec section
is very clear on this:

  4.1.3.1 Driver Requirements: PCI Device Layout

  The driver MUST access each field using the “natural” access method,
  i.e. 32-bit accesses for 32-bit fields, 16-bit accesses for 16-bit
  fields and 8-bit accesses for 8-bit fields.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2015-02-11 15:03:16 +10:30
Tetsuo Handa
5e05bf5833 virtio: Avoid possible kernel panic if DEBUG is enabled.
The virtqueue_add() calls START_USE() upon entry. The virtqueue_kick() is
called if vq->num_added == (1 << 16) - 1 before calling END_USE().
The virtqueue_kick_prepare() called via virtqueue_kick() calls START_USE()
upon entry, and will call panic() if DEBUG is enabled.
Move this virtqueue_kick() call to after END_USE() call.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-11 15:03:14 +10:30
Pawel Moll
1862ee22ce virtio-mmio: Update the device to OASIS spec version
This patch add a support for second version of the virtio-mmio device,
which follows OASIS "Virtual I/O Device (VIRTIO) Version 1.0"
specification.

Main changes:

1. The control register symbolic names use the new device/driver
   nomenclature rather than the old guest/host one.

2. The driver detect the device version (version 1 is the pre-OASIS
   spec, version 2 is compatible with fist revision of the OASIS spec)
   and drives the device accordingly.

3. New version uses direct addressing (64 bit address split into two
   low/high register) instead of the guest page size based one,
   and addresses each part of the queue (descriptors, available, used)
   separately.

4. The device activity is now explicitly triggered by writing to the
   "queue ready" register.

5. Whole 64 bit features are properly handled now (both ways).

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-23 14:57:10 +10:30
Michael S. Tsirkin
76545f066d virtio_pci_modern: drop an unused function
release function in modern driver is unused:
it's a left-over from when each driver had
to have its own release.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21 16:29:01 +10:30
Michael S. Tsirkin
ac399d8f39 virtio_pci: add module param to force legacy mode
If set, try legacy interface first, modern one if that fails.  Useful to
work around device/driver bugs, and for compatibility testing.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:29:01 +10:30
Michael S. Tsirkin
46506da5f3 virtio_pci: add an option to disable legacy driver
Useful for testing device virtio 1 compatibility.
Based on patch by Rusty - couldn't resist putting
that flying car joke in there!

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:59 +10:30
Michael S. Tsirkin
0327642337 virtio_pci: drop Kconfig warnings
The ABI *is* stable, and has been for a while now.
Drop Kconfig warning saying that it's not guaranteed
to work.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:59 +10:30
Michael S. Tsirkin
b2a6d51ddf virtio_pci: Kconfig grammar fix
This drivers -> this driver.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:58 +10:30
Michael S. Tsirkin
43b4f721ce virtio_ring: coding style fix
Most of our code has
struct foo {
}

Fix one instances where ring is inconsistent.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:57 +10:30
Michael S. Tsirkin
25e65e4efc virtio_balloon: coding style fixes
Most of our code has
struct foo {
}

Fix two instances where balloon is inconsistent.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:56 +10:30
Michael S. Tsirkin
d3f5f06560 virtio_pci_modern: support devices with no config
Virtio 1.0 spec lists device config as optional.
Set get/set callbacks to NULL. Drivers can check that
and fail gracefully.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:55 +10:30
Michael S. Tsirkin
3909213cfd virtio_pci_modern: reduce number of mappings
We don't know the # of VQs that drivers are going to use so it's hard to
predict how much memory we'll need to map. However, the relevant
capability does give us an upper limit.
If that's below a page, we can reduce the number of required
mappings by mapping it all once ahead of the time.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:55 +10:30
Rusty Russell
89461c4a12 virtio_pci: macros for PCI layout offsets
QEMU wants it, so why not?  Trust, but verify.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21 16:28:54 +10:30
Michael S. Tsirkin
1fcf0512c9 virtio_pci: modern driver
Lightly tested against qemu.

One thing *not* implemented here is separate mappings
for descriptor/avail/used rings. That's nice to have,
will be done later after we have core support.

This also exposes the PCI layout to userspace, and
adds macros for PCI layout offsets:

QEMU wants it, so why not?  Trust, but verify.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21 16:28:53 +10:30
Michael S. Tsirkin
ff31d2e285 virtio_pci: move probe/remove code to common
Most of initialization is device-independent.
Let's move it to common.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:51 +10:30
Sasha Levin
2bd56afd44 virtio_pci: drop useless del_vqs call
Device VQs were getting freed twice: once in every device's removal
functions, and then again in virtio_pci_legacy_remove().  The ones in
devices are called first, so drop the useless second call.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:50 +10:30
Michael S. Tsirkin
2d9becc1e0 virtio/balloon: verify device has config space
Some devices might not implement config space access
(e.g. remoteproc used not to - before 3.9).
virtio/balloon needs config space access so make it
fail gracefully if not there.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:48 +10:30
Michael S. Tsirkin
a1eb03f546 virtio_pci: document why we defer kfree
The reason we defer kfree until release function is because it's a
general rule for kobjects: kfree of the reference counter itself is only
legal in the release function.

Previous patch didn't make this clear, document this in code.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-06 16:35:36 +02:00
Sasha Levin
63bd62a08c virtio_pci: defer kfree until release callback
A struct device which has just been unregistered can live on past the
point at which a driver decides to drop it's initial reference to the
kobject gained on allocation.

This implies that when releasing a virtio device, we can't free a struct
virtio_device until the underlying struct device has been released,
which might not happen immediately on device_unregister().

Unfortunately, this is exactly what virtio pci does:
it has an empty release callback, and frees memory immediately
after unregistering the device.

This causes an easy to reproduce crash if CONFIG_DEBUG_KOBJECT_RELEASE
it enabled.

To fix, free the memory only once we know the device is gone in the release
callback.

Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-06 16:35:36 +02:00
Michael S. Tsirkin
945399a8c7 virtio_pci: device-specific release callback
It turns out we need to add device-specific code
in release callback. Move it to virtio_pci_legacy.c.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-06 16:35:36 +02:00
Michael S. Tsirkin
80e9541f79 virtio: make del_vqs idempotent
Our code calls del_vqs multiple times, assuming
it's idempotent.

commit 3ec7a77bb3
    virtio_pci: free up vq->priv
broke this assumption, by adding kfree there,
so multiple calls cause double free.

Fix it up.

Fixes: 3ec7a77bb3
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-06 16:35:35 +02:00
Linus Torvalds
64ec45bff6 vhost/virtio: virtio 1.0 related fixes
Most importantly, this fixes using virtio_pci as a module.
 
 Further, the big virtio 1.0 conversion missed a couple of places. This fixes
 them up.
 
 This isn't 100% sparse-clean yet because on many architectures get_user
 triggers sparse warnings when used with __bitwise tag (when same tag is on both
 pointer and value read).
 
 I posted a patchset to fix it up by adding __force on all
 arches that don't already have it (many do), when that's
 merged these warnings will go away.
 
 Cc: Rusty Russell <rusty@rustcorp.com.au>
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio fixes from Michael S Tsirkin:
 "virtio 1.0 related fixes

  Most importantly, this fixes using virtio_pci as a module.

  Further, the big virtio 1.0 conversion missed a couple of places.
  This fixes them up.

  This isn't 100% sparse-clean yet because on many architectures
  get_user triggers sparse warnings when used with __bitwise tag (when
  same tag is on both pointer and value read).

  I posted a patchset to fix it up by adding __force on all arches that
  don't already have it (many do), when that's merged these warnings
  will go away"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_pci: restore module attributes
  mic/host: fix up virtio 1.0 APIs
  vringh: update for virtio 1.0 APIs
  vringh: 64 bit features
  tools/virtio: add virtio 1.0 in vringh_test
  tools/virtio: add virtio 1.0 in virtio_test
  tools/virtio: enable -Werror
  tools/virtio: 64 bit features
  tools/virtio: fix vringh test
  tools/virtio: more stubs
  virtio: core support for config generation
  virtio_pci: add VIRTIO_PCI_NO_LEGACY
  virtio_pci: move probe to common file
  virtio_pci_common.h: drop VIRTIO_PCI_NO_LEGACY
  virtio_config: fix virtio_cread_bytes
  virtio: set VIRTIO_CONFIG_S_FEATURES_OK on restore
2014-12-18 20:50:30 -08:00
Linus Torvalds
9f3e151299 A balloon enhancement, and a minor race-on-module-unload theoretical
bug which doesn't merit cc: stable.
 
 All the exciting stuff went via MST this cycle.
 
 Thanks,
 Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio updates from Rusty Russell:
 "A balloon enhancement, and a minor race-on-module-unload theoretical
  bug which doesn't merit cc: stable.

  All the exciting stuff went via MST this cycle"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_balloon: free some memory from balloon on OOM
  virtio_balloon: return the amount of freed memory from leak_balloon()
  virtio_blk: fix race at module removal
  virtio: Fix comment typo 'CONFIG_S_FAILED'
2014-12-17 10:37:56 -08:00
Herbert Xu
5ff16110c6 virtio_pci: restore module attributes
When the virtio_pci driver was moved into virtio_pci_legacy.c the module
licence and other attributes went AWOL.  This patch restores them.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-17 00:59:40 +02:00
Linus Torvalds
e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00
Michael S. Tsirkin
9a4253db0c virtio_pci: move probe to common file
It turns out this make everything easier.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-14 15:10:30 +02:00
Michael S. Tsirkin
de2b48d581 virtio_pci_common.h: drop VIRTIO_PCI_NO_LEGACY
Legacy drivers use virtio_pci_common.h too, we should not
define VIRTIO_PCI_NO_LEGACY there.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-11 20:04:39 +02:00
Michael S. Tsirkin
30683a8cce virtio: set VIRTIO_CONFIG_S_FEATURES_OK on restore
virtio 1.0 devices require that drivers set VIRTIO_CONFIG_S_FEATURES_OK
after finalizing features.
virtio core missed doing this on restore, fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-11 20:04:38 +02:00
Michael S. Tsirkin
5f4c976089 virtio_pci: rename virtio_pci -> virtio_pci_common
kbuild does not seem to like it when we name source
files same as the module.
Let's rename virtio_pci -> virtio_pci_common,
and get rid of #include-ing c files.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:05 +02:00
Michael S. Tsirkin
a90fdce9dc virtio_pci: update file descriptions and copyright
There's been a lot of changes since 2007.
List main authors, add Red Hat copyright.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:05 +02:00
Michael S. Tsirkin
38eb4a29a7 virtio_pci: split out legacy device support
Move everything dealing with legacy devices out to virtio_pci_legacy.c.
Expose common code APIs in virtio_pci.h

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:04 +02:00
Michael S. Tsirkin
6f8f23d63d virtio_pci: setup config vector indirectly
config vector setup is version specific, do it indirectly.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:04 +02:00
Michael S. Tsirkin
b09f00bbfe virtio_pci: setup vqs indirectly
VQ setup is mostly version-specific, add another level of indirection to
split the version-independent code out.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:03 +02:00
Michael S. Tsirkin
5386cef200 virtio_pci: delete vqs indirectly
VQ deletion is mostly version-specific, add another level of indirection
to split the version-independent code out.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:02 +02:00
Michael S. Tsirkin
f30eaf4a09 virtio_pci: use priv for vq notification
slightly reduce the amount of pointer chasing this needs to do.
More importantly, this will easily generalize to virtio 1.0.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:02 +02:00
Michael S. Tsirkin
3ec7a77bb3 virtio_pci: free up vq->priv
We don't need to go from vq to vq info on
data path, so using direct vq->priv pointer for that
seems like a waste.

Let's build an array of vq infos, then we can use vq->index
for that lookup.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:01 +02:00
Michael S. Tsirkin
f913dd4536 virtio_pci: fix coding style for structs
should be

struct foo {
}

not

struct foo
{
}

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:01 +02:00
Michael S. Tsirkin
af535722f8 virtio_pci: add isr field
Use isr field instead of direct access to ioaddr.
This way generalizes easily to virtio 1.0.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:00 +02:00
Michael S. Tsirkin
d71a6fc6b9 virtio: drop legacy_only driver flag
legacy_only flag is now unused, drop it from core.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 21:42:00 +02:00
Michael S. Tsirkin
63d9f218a3 virtio_balloon: drop legacy_only driver flag
we have blacklisted balloon in core, no need
for a driver flag.

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

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 21:41:59 +02:00
Michael S. Tsirkin
5c609a5ef0 virtio: allow finalize_features to fail
This will make it easy for transports to validate features and return
failure.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 16:32:32 +02:00
Michael S. Tsirkin
b6098c3042 virtio: add API to detect legacy devices
transports need to be able to detect legacy-only
devices (ATM balloon only) to use legacy path
to drive them.

Add a core API to do just that.
The implementation just blacklists balloon:
not too pretty, but let's not over-engineer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:06:33 +02:00
Michael S. Tsirkin
747ae34a6e virtio: make VIRTIO_F_VERSION_1 a transport bit
Activate VIRTIO_F_VERSION_1 automatically unless legacy_only
is set.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:06:32 +02:00
Michael S. Tsirkin
df1b57fe59 virtio_balloon: add legacy_only flag
We have no plans to support virtio 1.0 in balloon driver.  Add an
explicit flag to mark it legacy only.

This will be used by follow-up patches.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:06:32 +02:00
Michael S. Tsirkin
b3bb62d119 virtio: add legacy feature table support
virtio-blk has some legacy feature bits that modern drivers
must not negotiate, but are needed for old legacy hosts
(that e.g. don't support virtio-scsi).
Allow a separate legacy feature table for such cases.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:26 +02:00
Michael S. Tsirkin
c102659d69 virtio: simplify feature bit handling
Now that we use u64 for bits, we can simply & them together.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:25 +02:00
Michael S. Tsirkin
cb3f6d9da4 virtio: set FEATURES_OK
set FEATURES_OK as per virtio 1.0 spec

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:25 +02:00
Cornelia Huck
8906265215 virtio: allow transports to get avail/used addresses
For virtio-1, we can theoretically have a more complex virtqueue
layout with avail and used buffers not on a contiguous memory area
with the descriptor table. For now, it's fine for a transport driver
to stay with the old layout: It needs, however, a way to access
the locations of the avail/used rings so it can register them with
the host.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:05:25 +02:00
Michael S. Tsirkin
00e6f3d9d9 virtio_ring: switch to new memory access APIs
Use virtioXX_to_cpu and friends for access to
all multibyte structures in memory.

Note: this is intentionally mechanical.
A follow-up patch will split long lines etc.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:25 +02:00