Commit Graph

72 Commits

Author SHA1 Message Date
Stefan Hajnoczi 8138405528 libvhost-user: return on error in vu_log_queue_fill()
vu_panic() is not guaranteed to exit the program. Return early when
errors are encountered.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200921113420.154378-3-stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-09-29 03:06:12 -04:00
Stefan Hajnoczi fd40901c82 libvhost-user: return early on virtqueue errors
vu_panic() is not guaranteed to exit the program. Return early when
errors are encountered.

Note that libvhost-user does not have an "unmap" operation for mapped
descriptors. Therefore it is correct to return without explicit cleanup.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200921113420.154378-2-stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-09-29 03:06:12 -04:00
Stefan Hajnoczi d73415a315 qemu/atomic.h: rename atomic_ to qatomic_
clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:

  $ CC=clang CXX=clang++ ./configure ... && make
  ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)

Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.

This patch was generated using:

  $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
    sort -u >/tmp/changed_identifiers
  $ for identifier in $(</tmp/changed_identifiers); do
        sed -i "s%\<$identifier\>%q$identifier%g" \
            $(git grep -I -l "\<$identifier\>")
    done

I manually fixed line-wrap issues and misaligned rST tables.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
2020-09-23 16:07:44 +01:00
Marc Hartmayer 2ffc547080 libvhost-user: handle endianness as mandated by the spec
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>
2020-09-23 13:41:58 +01:00
zhaolichang 639b090df5 contrib/: fix some comment spelling errors
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>
2020-09-17 20:41:44 +02:00
Paolo Bonzini 931049b46c contrib/libvhost-user: convert to Meson
Since libqemuutil.a has been converted to Meson, the conversion is
straightforward.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 06:30:08 -04:00
Philippe Mathieu-Daudé 8fe9805c73 libvhost-user: Report descriptor index on panic
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>
2020-07-27 10:28:28 -04:00
Stefan Hajnoczi a9a5c473d2 libvhost-user: advertise vring features
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>
2020-06-12 10:17:06 -04:00
Raphael Norwitz b650d5f4b1 Lift max ram slots limit in libvhost-user
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>
2020-06-12 10:17:06 -04:00
Raphael Norwitz 875b9fd97b Support individual region unmap in libvhost-user
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>
2020-06-12 10:17:06 -04:00
Raphael Norwitz ec94c8e621 Support adding individual regions in libvhost-user
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>
2020-06-12 10:17:06 -04:00
Raphael Norwitz 6fb2e173d2 Support ram slot configuration in libvhost-user
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>
2020-06-12 10:17:06 -04:00
Raphael Norwitz 08fccf8f07 Refactor out libvhost-user fault generation logic
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>
2020-06-12 10:17:06 -04:00
Philippe Mathieu-Daudé f7795e4096 misc: Replace zero-length arrays with flexible array member (automatic)
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>
2020-03-16 22:07:42 +01:00
Johannes Berg ff1320050a libvhost-user: implement in-band notifications
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>
2020-02-27 03:46:10 -05:00
Johannes Berg d5f99fc578 libvhost-user: handle NOFD flag in call/kick/err better
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>
2020-02-27 03:46:10 -05:00
Johannes Berg a00fdc9c9d libvhost-user-glib: use g_main_context_get_thread_default()
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>
2020-02-27 03:46:10 -05:00
Johannes Berg a7290a79fa libvhost-user-glib: fix VugDev main fd cleanup
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>
2020-02-27 03:46:10 -05:00
Johannes Berg 8899d60142 libvhost-user: implement VHOST_USER_PROTOCOL_F_REPLY_ACK
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>
2020-02-27 03:46:10 -05:00
Dr. David Alan Gilbert 49e9ec749d libvhost-user: Fix some memtable remap cases
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>
2020-01-23 16:41:37 +00:00
Dr. David Alan Gilbert c25c02b9e6 contrib/libvhost-user: Protect slave fd with mutex
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>
2020-01-23 16:41:37 +00:00
Xie Yongji d9b3ade54e libvhost-user: Zero memory allocated for VuVirtqInflightDesc
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>
2019-11-20 04:57:22 -05:00
Johannes Berg eeb39263aa libvhost-user: introduce and use vu_has_protocol_feature()
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>
2019-09-04 07:53:12 -04:00
Johannes Berg 8726b70b44 libvhost-user: fix SLAVE_SEND_FD handling
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>
2019-09-04 07:23:42 -04:00
Stefan Hajnoczi ea1b802ca2 libvhost-user: implement VHOST_USER_PROTOCOL_F_MQ
Existing vhost-user device backends, including vhost-user-scsi and
vhost-user-blk, support multiqueue but libvhost-user currently does not
advertise this.

VHOST_USER_PROTOCOL_F_MQ enables the VHOST_USER_GET_QUEUE_NUM request
needed for a vhost-user master to query the number of queues.  For
example, QEMU's vhost-user-net master depends on
VHOST_USER_PROTOCOL_F_MQ for multiqueue.

If you're wondering how any device backend with more than one virtqueue
functions today, it's because device types with a fixed number of
virtqueues do not require querying the number of queues.  Therefore the
vhost-user master for vhost-user-input with 2 virtqueues, for example,
doesn't actually depend on VHOST_USER_PROTOCOL_F_MQ.  It just enables
virtqueues 0 and 1 without asking.

Let there be multiqueue!

Suggested-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190626074815.19994-4-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Stefan Hajnoczi 6f5fd83788 libvhost-user: support many virtqueues
Currently libvhost-user is hardcoded to at most 8 virtqueues.  The
device backend should decide the number of virtqueues, not
libvhost-user.  This is important for multiqueue device backends where
the guest driver needs an accurate number of virtqueues.

This change breaks libvhost-user and libvhost-user-glib API stability.
There is no stability guarantee yet, so make this change now and update
all in-tree library users.

This patch touches up vhost-user-blk, vhost-user-gpu, vhost-user-input,
vhost-user-scsi, and vhost-user-bridge.  If the device has a fixed
number of queues that exact number is used.  Otherwise the previous
default of 8 virtqueues is used.

vu_init() and vug_init() can now fail if malloc() returns NULL.  I
considered aborting with an error in libvhost-user but it should be safe
to instantiate new vhost-user instances at runtime without risk of
terminating the process.  Therefore callers need to handle the vu_init()
failure now.

vhost-user-blk and vhost-user-scsi duplicate virtqueue index checks that
are already performed by libvhost-user.  This code would need to be
modified to use max_queues but remove it completely instead since it's
redundant.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190626074815.19994-3-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Stefan Hajnoczi db68f4ff06 libvhost-user: add vmsg_set_reply_u64() helper
The VhostUserMsg request is reused as the reply by message processing
functions.  This is risky since request fields may corrupt the reply if
the vhost-user message handler function forgets to re-initialize them.

Changing this practice would be very invasive but we can introduce a
helper function to make u64 payload replies safe.  This also eliminates
code duplication in message processing functions.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190626074815.19994-2-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Marc-André Lureau bd2e44fee4 vhost-user: add vhost_user_gpu_set_socket()
Add a new vhost-user message to give a unix socket to a vhost-user
backend for GPU display updates.

Back when I started that work, I added a new GPU channel because the
vhost-user protocol wasn't bidirectional. Since then, there is a
vhost-user-slave channel for the slave to send requests to the master.
We could extend it with GPU messages. However, the GPU protocol is
quite orthogonal to vhost-user, thus I chose to have a new dedicated
channel.

See vhost-user-gpu.rst for the protocol details.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190524130946.31736-2-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-29 06:29:07 +02:00
Marc-André Lureau 7fa9f0388c libvhost-user: fix -Werror=format= on ppc64
That should fix the following warning:

/home/pm215/qemu/contrib/libvhost-user/libvhost-user.c: In function
‘vu_set_mem_table_exec_postcopy’:
/home/pm215/qemu/contrib/libvhost-user/libvhost-user.c:666:9: error:
format ‘%llx’ expects argument of type ‘long long unsigned int’, but
argument 5 has type ‘__u64’ [-Werror=format=]
         DPRINT("%s: region %d: Registered userfault for %llx + %llx\n",
         ^
/home/pm215/qemu/contrib/libvhost-user/libvhost-user.c:666:9: error:
format ‘%llx’ expects argument of type ‘long long unsigned int’, but
argument 6 has type ‘__u64’ [-Werror=format=]
cc1: all warnings being treated as errors

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190514104126.6294-3-marcandre.lureau@redhat.com

{ kraxel: s/PRIu64/PRIx64/ ]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-22 07:16:17 +02:00
Marc-André Lureau 1005810b8a libvhost-user: fix cast warnings on 32 bits
Fixes warnings:
 warning: cast to pointer from integer of different size
 [-Wint-to-pointer-cast]

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190514104126.6294-2-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-22 07:14:16 +02:00
Li Feng acbd487ddb libvhost-user: fix bad vu_log_write
Mark dirty as page, the step of each call is 1.

Signed-off-by: Li Feng <fengli@smartx.com>
Message-Id: <20190420091016.213160-1-fengli@smartx.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>
2019-05-20 18:40:02 -04:00
Marc-André Lureau 78067fdef6 libvhost-user: add PROTOCOL_F_CONFIG if {set, get}_config
Add the config protocol feature bit if the set_config & get_config
callbacks are implemented.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190503130034.24916-3-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-10 12:48:35 +02:00
Marc-André Lureau d288eef3a0 libvhost-user: fix -Waddress-of-packed-member
/home/elmarco/src/qemu/contrib/libvhost-user/libvhost-user.c: In function ‘vu_set_mem_table_exec_postcopy’:
/home/elmarco/src/qemu/contrib/libvhost-user/libvhost-user.c:546:31: warning: taking address of packed member of ‘struct VhostUserMsg’ may result in an unaligned pointer value [-Waddress-of-packed-member]
  546 |     VhostUserMemory *memory = &vmsg->payload.memory;
      |                               ^~~~~~~~~~~~~~~~~~~~~
/home/elmarco/src/qemu/contrib/libvhost-user/libvhost-user.c: In function ‘vu_set_mem_table_exec’:
/home/elmarco/src/qemu/contrib/libvhost-user/libvhost-user.c:688:31: warning: taking address of packed member of ‘struct VhostUserMsg’ may result in an unaligned pointer value [-Waddress-of-packed-member]
  688 |     VhostUserMemory *memory = &vmsg->payload.memory;
      |                               ^~~~~~~~~~~~~~~~~~~~~
/home/elmarco/src/qemu/contrib/libvhost-user/libvhost-user.c: In function ‘vu_set_vring_addr_exec’:
/home/elmarco/src/qemu/contrib/libvhost-user/libvhost-user.c:817:36: warning: taking address of packed member of ‘struct VhostUserMsg’ may result in an unaligned pointer value [-Waddress-of-packed-member]
  817 |     struct vhost_vring_addr *vra = &vmsg->payload.addr;
      |                                    ^~~~~~~~~~~~~~~~~~~

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190503130034.24916-2-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-10 12:48:35 +02:00
Cao Jiaxi 48bb55bfaa QEMU_PACKED: Remove gcc_struct attribute in Windows non x86 targets
gcc_struct is for x86 only, and it generates an warning on ARM64 Clang/MinGW targets.

Signed-off-by: Cao Jiaxi <driver1998@foxmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: 20190503003618.10089-1-driver1998@foxmail.com
[PMM: dropped the slirp change as slirp is now a submodule]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-05-07 12:55:02 +01:00
Xie Yongji 5f9ff1eff3 libvhost-user: Support tracking inflight I/O in shared memory
This patch adds support for VHOST_USER_GET_INFLIGHT_FD and
VHOST_USER_SET_INFLIGHT_FD message to set/get shared buffer
to/from qemu. Then backend can track inflight I/O in this buffer.

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Message-Id: <20190228085355.9614-5-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 22:31:21 -04:00
Xie Yongji f7671f3d49 libvhost-user: Introduce vu_queue_map_desc()
Introduce vu_queue_map_desc() which should be
independent with vu_queue_pop();

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190228085355.9614-4-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 22:31:21 -04:00
Xie Yongji 792468cc6f libvhost-user: Remove unnecessary FD flag check for event file descriptors
The vu_check_queue_msg_file() has checked the FD flag. So let's
delete the redundant check after it.

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Message-Id: <20190228085355.9614-3-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 22:31:21 -04:00
Marc-André Lureau b13919ab64 libvhost-user: add vu_queue_unpop()
vhost-user-input will make use of this function to undo some queue pop
in case the virtio queue does not have enough room.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190308140454.32437-11-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 22:31:21 -04:00
Marc-André Lureau 922ef483ec libvhost-user-glib: export vug_source_new()
Simplify the creation of FD sources for other users. This is just
convenience to avoid duplicating similar code elsewhere.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190308140454.32437-10-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 22:31:21 -04:00
Marc-André Lureau 6079865526 libvhost-user: exit by default on VHOST_USER_NONE
Since commit 2566378d6d, libvhost-user
no longer panics on disconnect (rc == 0), and instead silently ignores
an invalid VHOST_USER_NONE message.

Without extra work from the API user, this will simply busy-loop on
HUP events. The obvious thing to do is to exit(0) instead, while
additional or different work can be done by overriding
iface->process_msg().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
Message-Id: <20190308140454.32437-5-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 21:22:31 -04:00
Marc-André Lureau ba275e9d28 libvhost-user: fix clang enum-conversion warning
Now that the VhostUserMsg.request field is used for both master &
slave requests, since commit d84599f56c820d8c1ac9928a76500dcdfbbf194d:

contrib/libvhost-user/libvhost-user.c:953:20: error: implicit conversion from enumeration type 'enum VhostUserSlaveRequest' to different enumeration type 'VhostUserRequest' (aka 'enum VhostUserRequest') [-Werror,-Wenum-conversion]
        .request = VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG,
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190308140454.32437-2-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 21:22:31 -04:00
Michael S. Tsirkin 8bafafcc29 contrib/libvhost-user: cleanup casts
Now that field types are all properly uint64_t,
drop the un-necessary cast.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-02-05 10:58:33 -05:00
Michael S. Tsirkin 9174d8ad74 contrib/libvhost-user: switch to uint64_t
contrib/libvhost-user is now using __u64 which is
a long long. New linux headers will use uint64_t.

These need to be printed differently: llx versus PRIx64.

For now cast to uint64_t for portability so the change
does not break the build.

Casts will go away in the future.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-02-04 00:08:53 -05:00
Tiwei Bie d84599f56c libvhost-user: support host notifier
This patch introduces the host notifier support in
libvhost-user. A new API is added to support setting
host notifier for each queue.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-24 21:14:11 +03:00
Dr. David Alan Gilbert e3638151da libvhost-user: Send messages with no data
The response to a VHOST_USER_POSTCOPY_ADVISE contains a fd but doesn't
actually contain any data.   FIx vu_message_write so that it doesn't
do a 0-byte write() call, since this was ending up with rc=0
that was confusing the error handling code.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.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>
2018-05-23 17:02:02 +03:00
Changpeng Liu ea3e6f5a93 contrib/libvhost-user: add the protocol feature used for SET/GET message
Signed-off-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-04-09 17:35:46 +03:00
Dr. David Alan Gilbert 4275cd99c6 libvhost-user: Claim support for postcopy
Tell QEMU we understand the protocol features needed for postcopy.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.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>
2018-03-20 16:40:37 +02:00
Dr. David Alan Gilbert c639187e33 vhost-user: Add VHOST_USER_POSTCOPY_END message
This message is sent just before the end of postcopy to get the
client to stop using userfault since we wont respond to any more
requests.  It should close userfaultfd so that any other pages
get mapped to the backing file automatically by the kernel, since
at this point we know we've received everything.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.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>
2018-03-20 16:40:37 +02:00
Dr. David Alan Gilbert 0185cfb30b libvhost-user: mprotect & madvises for postcopy
Clear the area and turn off THP.
PROT_NONE the area until after we've userfault advised it
to catch any unexpected changes.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.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>
2018-03-20 16:40:37 +02:00
Dr. David Alan Gilbert 9bb3801994 vhost+postcopy: Send address back to qemu
We need a better way, but at the moment we need the address of the
mappings sent back to qemu so it can interpret the messages on the
userfaultfd it reads.

This is done as a 3 stage set:
   QEMU -> client
      set_mem_table

   mmap stuff, get addresses

   client -> qemu
       here are the addresses

   qemu -> client
       OK - now you can use them

That ensures that qemu has registered the new addresses in it's
userfault code before the client starts accessing them.

Note: We don't ask for the default 'ack' reply since we've got our own.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.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>
2018-03-20 05:03:28 +02:00