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: NStefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200529161338.456017-1-stefanha@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>

This patch is to add standard commands defined in docs/interop/vhost-user.rst
For vhost-user-* program
Signed-off-by: NMicky Yun Chan (michiboo) <chanmickyyun@gmail.com>
Message-Id: <20191209015331.5455-1-chanmickyyun@gmail.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

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: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190626074815.19994-3-stefanha@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

This patch enables inflight I/O tracking for
vhost-user-blk backend so that we could restart it safely.
Signed-off-by: NXie Yongji <xieyongji@baidu.com>
Signed-off-by: NZhang Yu <zhangyu31@baidu.com>
Message-Id: <20190320112646.3712-8-xieyongji@baidu.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Signed-off-by: NChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NStefano Garzarella <sgarzare@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Message-Id: <1547615970-23545-2-git-send-email-changpeng.liu@intel.com>
[PMD: this patch was first (incorrectly) introduced as a56de056]
Signed-off-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190212140621.17009-3-philmd@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NPeter Xu <peterx@redhat.com>

Commit a56de056 squashed the following two unrelated commits
at once:

- "contrib/vhost-user-blk: fix the compilation issue"
  (Message-Id: 1547615970-23545-2-git-send-email-changpeng.liu@intel.com)
- "i386/kvm: ignore masked irqs when update msi routes"
  (Message-Id: 20190116030815.27273-5-peterx@redhat.com)

While the git history remains bisectable, having a commit that changes
MSI/MSIX code but describes it as "fix vhost-user-blk compilation" is
rather confusing.
Revert the offending commit to properly apply both patches separately.
Reported-by: NPeter Xu <peterx@redhat.com>
Fixes: a56de056Signed-off-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190212140621.17009-2-philmd@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NPeter Xu <peterx@redhat.com>

Linux commit 1f23816b8 "virtio_blk: add discard and write zeroes support"
added the support in the Guest kernel, while here also enable the features
support with vhost-user-blk driver. Also enable the test example utility
with DISCARD and WRITE ZEROES commands.
Signed-off-by: NChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Signed-off-by: NChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NStefano Garzarella <sgarzare@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

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, with the changes
to the following files manually reverted:

    contrib/libvhost-user/libvhost-user-glib.h
    contrib/libvhost-user/libvhost-user.c
    contrib/libvhost-user/libvhost-user.h
    linux-user/mips64/cpu_loop.c
    linux-user/mips64/signal.c
    linux-user/sparc64/cpu_loop.c
    linux-user/sparc64/signal.c
    linux-user/x86_64/cpu_loop.c
    linux-user/x86_64/signal.c
    target/s390x/gen-features.c
    tests/migration/s390x/a-b-bios.c
    tests/test-rcu-simpleq.c
    tests/test-rcu-tailq.c
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20181204172535.2799-1-armbru@redhat.com>
Acked-by: NEduardo Habkost <ehabkost@redhat.com>
Acked-by: NHalil Pasic <pasic@linux.ibm.com>
Acked-by: NYuval Shaia <yuval.shaia@oracle.com>
Acked-by: NViktor Prutyanov <viktor.prutyanov@phystech.edu>

Read only feature shouldn't be negotiable, because if the
backend device reported Read only feature supported, QEMU
host driver shouldn't change backend's RO attribute. While
here, also enable the vhost-user-blk test utility to test
RO feature.
Signed-off-by: NChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

This patch reports the protocol feature that is only advertised by
QEMU if the device implements the config ops.
Signed-off-by: NChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

This commit introduces a vhost-user-blk backend device, it uses UNIX
domain socket to communicate with QEMU. The vhost-user-blk sample
application should be used with QEMU vhost-user-blk-pci device.

To use it, complie with:
make vhost-user-blk

and start like this:
vhost-user-blk -b /dev/sdb -s /path/vhost.socket
Signed-off-by: NChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>