Since virtio existed even before it got standardized, the virtio
standard defines the following types of virtio devices:
+ legacy device (pre-virtio 1.0)
+ non-legacy or VIRTIO 1.0 device
+ transitional device (which can act both as legacy and non-legacy)
Virtio 1.0 defines the fields of the virtqueues as little endian,
while legacy uses guest's native endian [1]. Currently libvhost-user
does not handle virtio endianness at all, i.e. it works only if the
native endianness matches with whatever is actually needed. That means
things break spectacularly on big-endian targets. Let us handle virtio
endianness for non-legacy as required by the virtio specification [1]
and fence legacy virtio, as there is no safe way to figure out the
needed endianness conversions for all cases. The fencing of legacy
virtio devices is done in `vu_set_features_exec`.
[1] https://docs.oasis-open.org/virtio/virtio/v1.1/cs01/virtio-v1.1-cs01.html#x1-210003
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Message-id: 20200901150019.29229-3-mhartmay@linux.ibm.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
I found that there are many spelling errors in the comments of qemu,
so I used the spellcheck tool to check the spelling errors
and finally found some spelling errors in the contrib folder.
Signed-off-by: zhaolichang <zhaolichang@huawei.com>
Reviewed-by: Alex Bennee <alex.bennee@linaro.org>
Message-Id: <20200917075029.313-11-zhaolichang@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
We have an exploding complexity problem in the testing so lets just
move the more involved plugins into contrib. tests/plugins still exist
for the basic plugins that exercise the API. We restore the old
pre-meson style Makefile for contrib as it also doubles as a guide for
out-of-tree plugin builds.
While we are at it add some examples to the documentation and a
specific plugins build target.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200909112742.25730-11-alex.bennee@linaro.org>
When cross-compiling, by default qemu_datadir is 'c:\Program
Files\QEMU', which is not recognized as being an absolute path, and
meson will end up adding the prefix again.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200826110419.528931-6-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When pixman is not installed (or too old), but virglrenderer is available
and "configure" has been run with "--disable-system", the build currently
aborts when trying to compile vhost-user-gpu (since it requires pixman).
Let's skip the build of vhost-user-gpu when pixman is not installed or
too old. Instead of adding CONFIG_PIXMAN, it is simpler to move the
detection to pixman.
Based on a patch by Thomas Huth. <thuth@redhat.com>
Fixes: 9b52b17ba5 ("configure: Allow to build tools without pixman")
Reported-by: Rafael Kitover <rkitover@gmail.com>
Reported-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We can use config-host.mak to decide whether the tool has to be built,
apart from that the conversion is straightforward.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The libiscsi pkg-config information is extracted from config-host.mak and
used to link vhost-user-blk.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
With Makefiles that have automatically generated dependencies, you
generated includes are set as dependencies of the Makefile, so that they
are built before everything else and they are available when first
building the .c files.
Alternatively you can use a fine-grained dependency, e.g.
target/arm/translate.o: target/arm/decode-neon-shared.inc.c
With Meson you have only one choice and it is a third option, namely
"build at the beginning of the corresponding target"; the way you
express it is to list the includes in the sources of that target.
The problem is that Meson decides if something is a source vs. a
generated include by looking at the extension: '.c', '.cc', '.m', '.C'
are sources, while everything else is considered an include---including
'.inc.c'.
Use '.c.inc' to avoid this, as it is consistent with our other convention
of using '.rst.inc' for included reStructuredText files. The editorconfig
file is adjusted.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We want to report the index of the descriptor,
not its pointer.
Fixes: 7b2e5c65f4 ("contrib: add libvhost-user")
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200723171935.18535-1-philmd@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
libvhost-user implements several vring features without advertising
them. There is no way for the vhost-user master to detect support for
these features.
Things more or less work today because QEMU assumes the vhost-user
backend always implements certain feature bits like
VIRTIO_RING_F_EVENT_IDX. This is not documented anywhere.
This patch explicitly advertises features implemented in libvhost-user
so that the vhost-user master does not need to make undocumented
assumptions.
Feature bits that libvhost-user now advertises can be removed from
vhost-user-blk.c. Devices should not be responsible for advertising
vring feature bits, that is libvhost-user's job.
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200529161338.456017-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Historically, VMs with vhost-user devices could hot-add memory a maximum
of 8 times. Now that the VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS
protocol feature has been added, VMs with vhost-user backends which
support this new feature can support a configurable number of ram slots
up to the maximum supported by the target platform.
This change adds VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS support for
backends built with libvhost-user, and increases the number of supported
ram slots from 8 to 32.
Memory hot-add, hot-remove and postcopy migration were tested with
the vhost-user-bridge sample.
Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <1588533678-23450-11-git-send-email-raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When the VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS protocol feature is
enabled, on memory hot-unplug qemu will transmit memory regions to
remove individually using the new message VHOST_USER_REM_MEM_REG
message. With this change, vhost-user backends build with libvhost-user
can now unmap individual memory regions when receiving the
VHOST_USER_REM_MEM_REG message.
Qemu only sends VHOST_USER_REM_MEM_REG messages when the
VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS feature is negotiated, and
support for that feature has not yet been added in libvhost-user, this
new functionality is not yet used.
Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <1588533678-23450-10-git-send-email-raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When the VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS is enabled, qemu will
transmit memory regions to a backend individually using the new message
VHOST_USER_ADD_MEM_REG. With this change vhost-user backends built with
libvhost-user can now map in new memory regions when VHOST_USER_ADD_MEM_REG
messages are received.
Qemu only sends VHOST_USER_ADD_MEM_REG messages when the
VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS feature is negotiated, and
since it is not yet supported in libvhost-user, this new functionality
is not yet used.
Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <1588533678-23450-9-git-send-email-raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The VHOST_USER_GET_MAX_MEM_SLOTS message allows a vhost-user backend to
specify a maximum number of ram slots it is willing to support. This
change adds support for libvhost-user to process this message. For now
the backend will reply with 8 as the maximum number of regions
supported.
libvhost-user does not yet support the vhost-user protocol feature
VHOST_USER_PROTOCOL_F_CONFIGIRE_MEM_SLOTS, so qemu should never
send the VHOST_USER_GET_MAX_MEM_SLOTS message. Therefore this new
functionality is not currently used.
Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <1588533678-23450-8-git-send-email-raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
In libvhost-user, the incoming postcopy migration path for setting the
backend's memory tables has become convolued. In particular, moving the
logic which starts generating faults, having received the final ACK from
qemu can be moved to a separate function. This simplifies the code
substantially.
This logic will also be needed by the postcopy path once the
VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS feature is supported.
Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <1588533678-23450-7-git-send-email-raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
vu_queue_pop() returns memory that must be freed with free().
Cc: qemu-stable@nongnu.org
Reported-by: Coverity (CID 1421887 ALLOC_FREE_MISMATCH)
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Since commit d52c454aad ("contrib: add
vhost-user-gpu"), qemu-ga is linking with pixman.
This is because the Make-based build-system use a global namespace for
variables, and we rely on "main.o-libs" for different linking targets.
Note: this kind of variable clashing is hard to fix or prevent
currently. meson should help, as declarations have a linear
dependency and doesn't rely so much on variables and clever tricks.
Note2: we have a lot of main.c (or other duplicated names!) in
tree. Imho, it would be annoying and a bad workaroud to rename all
those to avoid conflicts like I did here.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1811670
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200311160923.882474-1-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Description copied from Linux kernel commit from Gustavo A. R. Silva
(see [3]):
--v-- description start --v--
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to
declare variable-length types such as these ones is a flexible
array member [1], introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler
warning in case the flexible array does not occur last in the
structure, which will help us prevent some kind of undefined
behavior bugs from being unadvertenly introduced [2] to the
Linux codebase from now on.
--^-- description end --^--
Do the similar housekeeping in the QEMU codebase (which uses
C99 since commit 7be41675f7).
All these instances of code were found with the help of the
following Coccinelle script:
@@
identifier s, m, a;
type t, T;
@@
struct s {
...
t m;
- T a[0];
+ T a[];
};
@@
identifier s, m, a;
type t, T;
@@
struct s {
...
t m;
- T a[0];
+ T a[];
} QEMU_PACKED;
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76497732932f
[3] https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/?id=17642a2fbd2c1
Inspired-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add support for VHOST_USER_PROTOCOL_F_IN_BAND_NOTIFICATIONS, but
as it's not desired by default, don't enable it unless the device
implementation opts in by returning it from its protocol features
callback.
Note that I updated vu_set_vring_err_exec(), but didn't add any
sending of the VHOST_USER_SLAVE_VRING_ERR message as there's no
write to the err_fd today either.
This also adds vu_queue_notify_sync() which can be used to force
a synchronous notification if inband notifications are supported.
Previously, I had left out the slave->master direction handling
of F_REPLY_ACK, this now adds some code to support it as well.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20200123081708.7817-7-johannes@sipsolutions.net>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The code here is odd, for example will it print out invalid
file descriptor numbers that were never sent in the message.
Clean that up a bit so it's actually possible to implement
a device that uses polling.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20200123081708.7817-5-johannes@sipsolutions.net>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If we use NULL, we just get the main program default mainloop
here. Using g_main_context_get_thread_default() has basically
the same effect, but it lets us start different devices in
different threads with different mainloops, which can be useful.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20200123081708.7817-4-johannes@sipsolutions.net>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If you try to make a device implementation that can handle multiple
connections and allow disconnections (which requires overriding the
VHOST_USER_NONE handling), then glib will warn that we remove a src
while it's still on the mainloop, and will poll() an FD that doesn't
exist anymore.
Fix this by making vug_source_new() require pairing with the new
vug_source_destroy() so we can keep the GSource referenced in the
meantime.
Note that this requires calling the new API in vhost-user-input.
vhost-user-gpu also uses vug_source_new(), but never seems to free
the result at all, so I haven't changed anything there.
Fixes: 8bb7ddb78a ("libvhost-user: add glib source helper")
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20200123081708.7817-3-johannes@sipsolutions.net>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This is really simple, since we know whether a response is
already requested or not, so we can just send a (successful)
response when there isn't one already.
Given that, it's not all _that_ useful but the master can at
least be sure the message was processed, and we can exercise
more code paths using the example code.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20200123081708.7817-2-johannes@sipsolutions.net>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Fixes: a5d2f6f877
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200218094402.26625-14-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
If a new setmemtable command comes in once the vhost threads are
running, it will remap the guests address space and the threads
will now be looking in the wrong place.
Fortunately we're running this command under lock, so we can
update the queue mappings so that threads will look in the new-right
place.
Note: This doesn't fix things that the threads might be doing
without a lock (e.g. a readv/writev!) That's for another time.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
In future patches we'll be performing commands on the slave-fd driven
by commands on queues, since those queues will be driven by individual
threads we need to make sure they don't attempt to use the slave-fd
for multiple commands in parallel.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This patch is to add standard commands defined in docs/interop/vhost-user.rst
For vhost-user-* program
Signed-off-by: Micky Yun Chan (michiboo) <chanmickyyun@gmail.com>
Message-Id: <20191209015331.5455-1-chanmickyyun@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Fixes:
../contrib/vhost-user-scsi/vhost-user-scsi.c:118:57: error: format specifies
type 'unsigned char' but the argument has type 'int' [-Werror,-Wformat]
g_warning("Unable to determine cdb len (0x%02hhX)", cdb[0] >> 5);
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The virtqueue element returned by vu_queue_pop() is allocated using
malloc(3) by virtqueue_alloc_element(). Use the matching free(3)
function instead of glib's g_free().
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20191119111626.112206-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Use a zero-initialized VuVirtqInflightDesc struct to avoid
that scan-build reports that vq->resubmit_list[0].counter may
be garbage value in vu_check_queue_inflights().
Fixes: 5f9ff1eff ("libvhost-user: Support tracking inflight I/O in
shared memory")
Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Message-Id: <20191119075759.4334-1-xieyongji@baidu.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
So far, the server leaves the posix shared memory object behind when
terminating, requiring the user to explicitly remove it in order to
start a new instance.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Claudio Fontana <claudio.fontana@suse.com>
Message-Id: <d938a62c-7538-9d2b-cc0a-13b240ab9141@web.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
- Add a few individuals
- Add China Mobile
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Merge remote-tracking branch 'remotes/stsquad/tags/pull-gitdm-next-271019-1' into staging
gitdm updates
- Add a few individuals
- Add China Mobile
# gpg: Signature made Sun 27 Oct 2019 19:21:15 GMT
# gpg: using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [full]
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8 DF35 FBD0 DB09 5A9E 2A44
* remotes/stsquad/tags/pull-gitdm-next-271019-1:
contrib/gitdm: add China Mobile to the domain map
contrib/gitdm: add Andrey to the individual group
contrib/gitdm: add Emanuele as an individual
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We've had a number of contributions from this domain. Mao has
confirmed they are company contributions.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Mao Zhongyi <maozhongyi@cmss.chinamobile.com>
Cc: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Again this is guess work based on public websites. Please confirm.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Emanuele Giuseppe Esposito <e.emanuelegiuseppe@gmail.com>
There are three page size in qemu:
real host page size
host page size
target page size
All of them have dedicate variable to represent. For the last two, we
use the same form in the whole qemu project, while for the first one we
use two forms: qemu_real_host_page_size and getpagesize().
qemu_real_host_page_size is defined to be a replacement of
getpagesize(), so let it serve the role.
[Note] Not fully tested for some arch or device.
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191013021145.16011-3-richardw.yang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This simplifies the various has_feature() checks, we already
have vu_has_feature() but it checks features, not protocol
features.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20190904065021.1360-1-johannes@sipsolutions.net>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
It doesn't look like this could possibly work properly since
VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD is defined to 10, but the
dev->protocol_features has a bitmap. I suppose the peer this
was tested with also supported VHOST_USER_PROTOCOL_F_LOG_SHMFD,
in which case the test would always be false, but nevertheless
the code seems wrong.
Use has_feature() to fix this.
Fixes: d84599f56c ("libvhost-user: support host notifier")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20190903200422.11693-1-johannes@sipsolutions.net>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>