Commit Graph

265 Commits

Author SHA1 Message Date
Greg Kurz
d506dc87b9 9p: drop unused declaration from coth.h
Commit "ebac1202c95a virtio-9p: use QEMU thread pool" dropped function
v9fs_init_worker_threads.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-05-18 15:04:27 +03:00
Veronia Bahaa
f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster
da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Peter Maydell
30456d5ba3 all: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 12:43:05 +00:00
Paolo Bonzini
51b19ebe43 virtio: move allocation to virtqueue_pop/vring_pop
The return code of virtqueue_pop/vring_pop is unused except to check for
errors or 0.  We can thus easily move allocation inside the functions
and just return a pointer to the VirtQueueElement.

The advantage is that we will be able to allocate only the space that
is needed for the actual size of the s/g list instead of the full
VIRTQUEUE_MAX_SIZE items.  Currently VirtQueueElement takes about 48K
of memory, and this kind of allocation puts a lot of stress on malloc.
By cutting the size by two or three orders of magnitude, malloc can
use much more efficient algorithms.

The patch is pretty large, but changes to each device are testable
more or less independently.  Splitting it would mostly add churn.

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: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-02-06 20:39:07 +02:00
Peter Maydell
fbc0412709 9pfs: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-18-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:23 +00:00
Peter Maydell
9b8bfe21be virtio: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-15-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:23 +00:00
Greg Kurz
63325b181f 9pfs: use error_report() instead of fprintf(stderr)
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-01-22 15:12:17 +01:00
Wei Liu
00588a0aa2 9pfs: introduce V9fsVirtioState
V9fsState now only contains generic fields. Introduce V9fsVirtioState
for virtio transport.  Change virtio-pci and virtio-ccw to use
V9fsVirtioState.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-12 11:04:14 +05:30
Wei Liu
2a0c56aa4c 9pfs: factor out v9fs_device_{,un}realize_common
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:33:24 +05:30
Wei Liu
60ce86c714 9pfs: rename virtio-9p.c to 9p.c
Now that file only contains generic code.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:32:13 +05:30
Wei Liu
72a189770a 9pfs: rename virtio_9p_set_fd_limit to use v9fs_ prefix
It's not virtio specific.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
2016-01-08 15:31:49 +05:30
Wei Liu
0192cc5d79 9pfs: move handle_9p_output and make it static function
It's only used in virtio device.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:31:25 +05:30
Wei Liu
4b311c5f0b 9pfs: export pdu_{submit,alloc,free}
They will be used in later patches.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:30:39 +05:30
Wei Liu
0d3716b4e6 9pfs: factor out virtio_9p_push_and_notify
The new function resides in virtio specific file.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:30:03 +05:30
Wei Liu
ebe74f8ba2 9pfs: break out 9p.h from virtio-9p.h
Move out generic definitions from virtio-9p.h to 9p.h. Fix header
inclusions.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:25:30 +05:30
Wei Liu
592707af7f 9pfs: break out virtio_init_iov_from_pdu
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:23:02 +05:30
Wei Liu
f657b17a63 9pfs: factor out pdu_push_and_notify
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:20:02 +05:30
Wei Liu
fe9fa96d7c 9pfs: factor out virtio_pdu_{,un}marshal
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:19:40 +05:30
Wei Liu
0e2082d9e5 9pfs: make pdu_{,un}marshal proper functions
Factor out v9fs_iov_v{,un}marshal. Implement pdu_{,un}marshal with those
functions.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 14:53:39 +05:30
Wei Liu
dc295f8353 9pfs: PDU processing functions should start pdu_ prefix
This matches naming convention of pdu_marshal and pdu_unmarshal.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 14:35:59 +05:30
Wei Liu
ad38ce9ed1 9pfs: PDU processing functions don't need to take V9fsState as argument
V9fsState can be referenced by pdu->s. Initialise that in device
realization function.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 14:35:17 +05:30
Wei Liu
2209bd050a fsdev: rename virtio-9p-marshal.{c,h} to 9p-iov-marshal.{c,h}
And rename v9fs_marshal to v9fs_iov_marshal, v9fs_unmarshal to
v9fs_iov_unmarshal.

The rationale behind this change is that, this marshalling interface is
used both by virtio and proxy helper. Renaming files and functions to
reflect the true nature of this interface.

Xen transport is going to have its own marshalling interface.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 14:35:06 +05:30
Wei Liu
71042cffc0 9pfs: remove dead code
Some structures in virtio-9p.h have been unused since 2011 when relevant
functions switched to use coroutines.

The declaration of pdu_packunpack and function do_pdu_unpack are
useless.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:56:03 +05:30
Wei Liu
756cb74a59 9pfs: merge hw/virtio/virtio-9p.h into hw/9pfs/virtio-9p.h
The deleted file only contained V9fsConf which wasn't virtio specific.
Merge that to the general header of 9pfs.

Fixed header inclusions as I went along.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:48:11 +05:30
Wei Liu
267ae092e2 9pfs: rename virtio-9p-xattr{,-user}.{c,h} to 9p-xattr{,-user}.{c,h}
These three files are not virtio specific. Rename them to generic
names.

Fix comments and header inclusion in various files.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:47:35 +05:30
Wei Liu
364031f179 9pfs: rename virtio-9p-synth.{c,h} to 9p-synth.{c,h}
These two files are not virtio specific. Rename them to use generic
names.

Fix includes in various C files. Change define guards and comments
in header files.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:40:55 +05:30
Wei Liu
494a8ebe71 9pfs: rename virtio-9p-proxy.{c,h} to 9p-proxy.{c,h}
Those two files are not virtio specific. Rename them to use generic
names.

Fix includes in various C files. Change define guards and comments
in header files.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:38:15 +05:30
Wei Liu
d57b78002c 9pfs: rename virtio-9p-posix-acl.c to 9p-posix-acl.c
This file is not virtio specific. Rename it to use generic name.

Fix comment and remove unneeded inclusion of virtio.h.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:37:32 +05:30
Wei Liu
f00d4f596b 9pfs: rename virtio-9p-local.c to 9p-local.c
This file is not virtio specific. Rename it to use generic name.

Fix comment and remove unneeded inclusion of virtio.h.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:36:44 +05:30
Wei Liu
3b9ca04653 9pfs: rename virtio-9p-handle.c to 9p-handle.c
This file is not virtio specific. Rename it to use generic name.

Fix comment and remove unneeded inclusion of virtio.h.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:35:46 +05:30
Wei Liu
fe52840c87 9pfs: rename virtio-9p-coth.{c,h} to coth.{c,h}
Those two files are not virtio specific. Rename them to use generic
names.

Fix includes in various C files. Change define guards and comments in
header files.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:04:43 +05:30
Greg Kurz
4b3a4f2d45 virtio-9p: use accessor to get thread_pool
The aio_context_new() function does not allocate a thread pool. This is
deferred to the first call to the aio_get_thread_pool() accessor. It is
hence forbidden to access the thread_pool field directly, as it may be
NULL. The accessor *must* be used always.

Fixes: ebac1202c9
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
Cc: qemu-stable@nongnu.org
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2015-12-23 10:56:58 +01:00
Greg Kurz
6cecf09373 virtio-9p-device: add minimal unrealize handler
Since commit 4652f1640e "virtio-9p: add savevm
handlers", if the user hot-unplugs a quiescent 9p device and live
migrates, the source QEMU crashes before migration completetion...
This happens because virtio-9p devices have a realize handler which
calls virtio_init() and register_savevm().  Both calls store pointers
to the device internals, that get dereferenced during migration even
if the device got unplugged.

This patch simply adds an unrealize handler to perform minimal
cleanup and avoid the crash.  Hot unplug of non-quiescent 9p devices
is still not supported in QEMU, and not supported by linux guests
either.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20151208155457.27775.69441.stgit@bahia.huguette.org
[PMM: rewrapped long lines in commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-12-10 10:46:22 +00:00
Paolo Bonzini
ebac1202c9 virtio-9p: use QEMU thread pool
The QEMU thread pool already has a mechanism to invoke callbacks in the main
thread.  It does not need an EventNotifier and it is more efficient too.
Use it instead of GAsyncQueue + GThreadPool + glue.

As a side effect, it silences Coverity's complaint about an unchecked
return value for event_notifier_init.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
(removed no more needed #include <glib.h> from virtio-9p-coth.h)
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2015-11-30 12:36:12 +01:00
Greg Kurz
4652f1640e virtio-9p: add savem handlers
We don't support migration of mounted 9p shares. This is handled by a
migration blocker.

One would expect, however, to be able to migrate if the share is unmounted.
Unfortunately virtio-9p-device does not register savevm handlers at all !
Migration succeeds and leaves the guest with a dangling device...

This patch simply registers migration handlers for virtio-9p-device. Whether
migration is possible or not still depends on the migration blocker.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-11-12 16:40:14 +02:00
Daniel P. Berrange
10817bf09d coroutine: move into libqemuutil.a library
The coroutine files are currently referenced by the block-obj-y
variable. The coroutine functionality though is already used by
more than just the block code. eg migration code uses coroutine
yield. In the future the I/O channel code will also use the
coroutine yield functionality. Since the coroutine code is nicely
self-contained it can be easily built as part of the libqemuutil.a
library, making it widely available.

The headers are also moved into include/qemu, instead of the
include/block directory, since they are now part of the util
codebase, and the impl was never in the block/ directory
either.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-10-20 14:59:04 +01:00
Jason Wang
9d5b731dd2 virtio: get_features() can fail
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>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-27 18:11:53 +03:00
Michael S. Tsirkin
cd4bfbb20d virtio-9p: fix any_layout
virtio pci allows any device to have a modern interface,
this in turn requires ANY_LAYOUT support.
Fix up ANY_LAYOUT for virtio-9p.

Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
2015-07-27 11:24:48 +03:00
Markus Armbruster
d49b683644 qerror: Move #include out of qerror.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:40 +02:00
Shannon Zhao
83a84878da virtio-9p-device: move qdev properties into virtio-9p-device.c
As only one place in virtio-9p-device.c uses
DEFINE_VIRTIO_9P_PROPERTIES, there is no need to expose it. Inline it
into virtio-9p-device.c to avoid wrongly use.

Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-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>
2015-06-10 18:15:34 +02:00
Gerd Hoffmann
019a3edbb2 virtio: make features 64bit wide
Make features 64bit wide everywhere.

On migration a full 64bit guest_features field is sent if one of the
high bits is set, in addition to the lower 32bit guest_features field
which must stay for compatibility reasons.  That way we send the lower
32 feature bits twice, but the code is simpler because we don't have
to split and compose the 64bit features into two 32bit fields.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-01 14:18:55 +02:00
Stefan Weil
0289a412e8 9pfs: Fix warnings from Sparse
Sparse report:

9pfs/virtio-9p.c:1953:9: warning: returning void-valued expression
9pfs/virtio-9p-handle.c:143:5: warning: returning void-valued expression
9pfs/virtio-9p-handle.c:160:5: warning: returning void-valued expression
9pfs/virtio-9p-local.c:384:5: warning: returning void-valued expression
9pfs/virtio-9p-local.c:415:5: warning: returning void-valued expression
9pfs/virtio-9p-proxy.c:672:5: warning: returning void-valued expression
9pfs/virtio-9p-proxy.c:689:5: warning: returning void-valued expression

Cc: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-19 11:11:55 +03:00
Stefan Weil
4ed7b2c3a7 virtio: Fix memory leaks reported by Coverity
All four leaks are similar, so fix them in one patch.
Success path was not doing memory free.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-16 13:32:24 +05:30
Shannon Zhao
25ee9a7fa3 virtfs-proxy: Fix possible overflow
It's detected by coverity. The socket name specified
should fit in the sockadd_un.sun_path. If not abort.

Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-16 13:29:12 +05:30
Shannon Zhao
9005c3b3ef hw/9pfs/virtio-9p-posix-acl: Fix out-of-bounds access
It's detected by coverity. Fix out-of-bounds access of the function mp_dacl_listxattr.

Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-13 14:01:24 +05:30
Michael Tokarev
7752efcacf 9pfs-proxy: tiny cleanups in proxy_pwritev and proxy_preadv
Don't compare syscall return with -1, use "<0" condition.
Don't introduce useless local variables when we already
have similar variable
Rename local variable to be consistent with other usages
Finally make the two methods, read and write, to be similar to each other

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-12 15:27:35 +05:30
Michael Tokarev
1b6f85e2cb 9pfs-local: simplify/optimize local_mapped_attr_path()
Omit one unnecessary memory allocation for components
of the path and create the resulting path directly given
lengths of the components.

Do not use basename(3) because there are 2 versions of
this function which differs when argument ends with
slash character, use strrchr() instead so we have
consistent result.  This also makes sure the function
will do the right thing in corner cases (eg, empty
pathname is given), when basename(3) return entirely
another string.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-12 15:23:05 +05:30
Michael Tokarev
438940cbc2 9pfs: remove useless return
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-10 08:15:34 +03:00
Cornelia Huck
0cd09c3a6c virtio: feature bit manipulation helpers
Add virtio_{add,clear}_feature helper functions for manipulating a
feature bits variable. This has some benefits over open coding:
- add check that the bit is in a sane range
- make it obvious at a glance what is going on
- have a central point to change when we want to extend feature bits

Convert existing code manipulating features to use the new helpers.

Signed-off-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>
2015-02-26 13:04:07 +01:00