qemu-e2k/backends/cryptodev-vhost.c
Stefano Garzarella 4daa5054c5 vhost: enable vrings in vhost_dev_start() for vhost-user devices
Commit 02b61f38d3 ("hw/virtio: incorporate backend features in features")
properly negotiates VHOST_USER_F_PROTOCOL_FEATURES with the vhost-user
backend, but we forgot to enable vrings as specified in
docs/interop/vhost-user.rst:

    If ``VHOST_USER_F_PROTOCOL_FEATURES`` has not been negotiated, the
    ring starts directly in the enabled state.

    If ``VHOST_USER_F_PROTOCOL_FEATURES`` has been negotiated, the ring is
    initialized in a disabled state and is enabled by
    ``VHOST_USER_SET_VRING_ENABLE`` with parameter 1.

Some vhost-user front-ends already did this by calling
vhost_ops.vhost_set_vring_enable() directly:
- backends/cryptodev-vhost.c
- hw/net/virtio-net.c
- hw/virtio/vhost-user-gpio.c

But most didn't do that, so we would leave the vrings disabled and some
backends would not work. We observed this issue with the rust version of
virtiofsd [1], which uses the event loop [2] provided by the
vhost-user-backend crate where requests are not processed if vring is
not enabled.

Let's fix this issue by enabling the vrings in vhost_dev_start() for
vhost-user front-ends that don't already do this directly. Same thing
also in vhost_dev_stop() where we disable vrings.

[1] https://gitlab.com/virtio-fs/virtiofsd
[2] https://github.com/rust-vmm/vhost/blob/240fc2966/crates/vhost-user-backend/src/event_loop.rs#L217

Fixes: 02b61f38d3 ("hw/virtio: incorporate backend features in features")
Reported-by: German Maglione <gmaglione@redhat.com>
Tested-by: German Maglione <gmaglione@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20221123131630.52020-1-sgarzare@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20221130112439.2527228-3-alex.bennee@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-12-01 02:30:04 -05:00

351 lines
8.8 KiB
C

/*
* QEMU Cryptodev backend for QEMU cipher APIs
*
* Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
*
* Authors:
* Gonglei <arei.gonglei@huawei.com>
* Jay Zhou <jianjay.zhou@huawei.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
*/
#include "qemu/osdep.h"
#include "hw/virtio/virtio-bus.h"
#include "sysemu/cryptodev-vhost.h"
#ifdef CONFIG_VHOST_CRYPTO
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "qemu/error-report.h"
#include "hw/virtio/virtio-crypto.h"
#include "sysemu/cryptodev-vhost-user.h"
uint64_t
cryptodev_vhost_get_max_queues(
CryptoDevBackendVhost *crypto)
{
return crypto->dev.max_queues;
}
void cryptodev_vhost_cleanup(CryptoDevBackendVhost *crypto)
{
vhost_dev_cleanup(&crypto->dev);
g_free(crypto);
}
struct CryptoDevBackendVhost *
cryptodev_vhost_init(
CryptoDevBackendVhostOptions *options)
{
int r;
CryptoDevBackendVhost *crypto;
Error *local_err = NULL;
crypto = g_new(CryptoDevBackendVhost, 1);
crypto->dev.max_queues = 1;
crypto->dev.nvqs = 1;
crypto->dev.vqs = crypto->vqs;
crypto->cc = options->cc;
crypto->dev.protocol_features = 0;
crypto->backend = -1;
/* vhost-user needs vq_index to initiate a specific queue pair */
crypto->dev.vq_index = crypto->cc->queue_index * crypto->dev.nvqs;
r = vhost_dev_init(&crypto->dev, options->opaque, options->backend_type, 0,
&local_err);
if (r < 0) {
error_report_err(local_err);
goto fail;
}
return crypto;
fail:
g_free(crypto);
return NULL;
}
static int
cryptodev_vhost_start_one(CryptoDevBackendVhost *crypto,
VirtIODevice *dev)
{
int r;
crypto->dev.nvqs = 1;
crypto->dev.vqs = crypto->vqs;
r = vhost_dev_enable_notifiers(&crypto->dev, dev);
if (r < 0) {
goto fail_notifiers;
}
r = vhost_dev_start(&crypto->dev, dev, false);
if (r < 0) {
goto fail_start;
}
return 0;
fail_start:
vhost_dev_disable_notifiers(&crypto->dev, dev);
fail_notifiers:
return r;
}
static void
cryptodev_vhost_stop_one(CryptoDevBackendVhost *crypto,
VirtIODevice *dev)
{
vhost_dev_stop(&crypto->dev, dev, false);
vhost_dev_disable_notifiers(&crypto->dev, dev);
}
CryptoDevBackendVhost *
cryptodev_get_vhost(CryptoDevBackendClient *cc,
CryptoDevBackend *b,
uint16_t queue)
{
CryptoDevBackendVhost *vhost_crypto = NULL;
if (!cc) {
return NULL;
}
switch (cc->type) {
#if defined(CONFIG_VHOST_USER) && defined(CONFIG_LINUX)
case CRYPTODEV_BACKEND_TYPE_VHOST_USER:
vhost_crypto = cryptodev_vhost_user_get_vhost(cc, b, queue);
break;
#endif
default:
break;
}
return vhost_crypto;
}
static void
cryptodev_vhost_set_vq_index(CryptoDevBackendVhost *crypto,
int vq_index)
{
crypto->dev.vq_index = vq_index;
}
static int
vhost_set_vring_enable(CryptoDevBackendClient *cc,
CryptoDevBackend *b,
uint16_t queue, int enable)
{
CryptoDevBackendVhost *crypto =
cryptodev_get_vhost(cc, b, queue);
const VhostOps *vhost_ops;
cc->vring_enable = enable;
if (!crypto) {
return 0;
}
vhost_ops = crypto->dev.vhost_ops;
if (vhost_ops->vhost_set_vring_enable) {
return vhost_ops->vhost_set_vring_enable(&crypto->dev, enable);
}
return 0;
}
int cryptodev_vhost_start(VirtIODevice *dev, int total_queues)
{
VirtIOCrypto *vcrypto = VIRTIO_CRYPTO(dev);
BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
VirtioBusState *vbus = VIRTIO_BUS(qbus);
VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
int r, e;
int i;
CryptoDevBackend *b = vcrypto->cryptodev;
CryptoDevBackendVhost *vhost_crypto;
CryptoDevBackendClient *cc;
if (!k->set_guest_notifiers) {
error_report("binding does not support guest notifiers");
return -ENOSYS;
}
for (i = 0; i < total_queues; i++) {
cc = b->conf.peers.ccs[i];
vhost_crypto = cryptodev_get_vhost(cc, b, i);
cryptodev_vhost_set_vq_index(vhost_crypto, i);
/* Suppress the masking guest notifiers on vhost user
* because vhost user doesn't interrupt masking/unmasking
* properly.
*/
if (cc->type == CRYPTODEV_BACKEND_TYPE_VHOST_USER) {
dev->use_guest_notifier_mask = false;
}
}
r = k->set_guest_notifiers(qbus->parent, total_queues, true);
if (r < 0) {
error_report("error binding guest notifier: %d", -r);
goto err;
}
for (i = 0; i < total_queues; i++) {
cc = b->conf.peers.ccs[i];
vhost_crypto = cryptodev_get_vhost(cc, b, i);
r = cryptodev_vhost_start_one(vhost_crypto, dev);
if (r < 0) {
goto err_start;
}
if (cc->vring_enable) {
/* restore vring enable state */
r = vhost_set_vring_enable(cc, b, i, cc->vring_enable);
if (r < 0) {
goto err_start;
}
}
}
return 0;
err_start:
while (--i >= 0) {
cc = b->conf.peers.ccs[i];
vhost_crypto = cryptodev_get_vhost(cc, b, i);
cryptodev_vhost_stop_one(vhost_crypto, dev);
}
e = k->set_guest_notifiers(qbus->parent, total_queues, false);
if (e < 0) {
error_report("vhost guest notifier cleanup failed: %d", e);
}
err:
return r;
}
void cryptodev_vhost_stop(VirtIODevice *dev, int total_queues)
{
BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
VirtioBusState *vbus = VIRTIO_BUS(qbus);
VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
VirtIOCrypto *vcrypto = VIRTIO_CRYPTO(dev);
CryptoDevBackend *b = vcrypto->cryptodev;
CryptoDevBackendVhost *vhost_crypto;
CryptoDevBackendClient *cc;
size_t i;
int r;
for (i = 0; i < total_queues; i++) {
cc = b->conf.peers.ccs[i];
vhost_crypto = cryptodev_get_vhost(cc, b, i);
cryptodev_vhost_stop_one(vhost_crypto, dev);
}
r = k->set_guest_notifiers(qbus->parent, total_queues, false);
if (r < 0) {
error_report("vhost guest notifier cleanup failed: %d", r);
}
assert(r >= 0);
}
void cryptodev_vhost_virtqueue_mask(VirtIODevice *dev,
int queue,
int idx, bool mask)
{
VirtIOCrypto *vcrypto = VIRTIO_CRYPTO(dev);
CryptoDevBackend *b = vcrypto->cryptodev;
CryptoDevBackendVhost *vhost_crypto;
CryptoDevBackendClient *cc;
assert(queue < MAX_CRYPTO_QUEUE_NUM);
cc = b->conf.peers.ccs[queue];
vhost_crypto = cryptodev_get_vhost(cc, b, queue);
vhost_virtqueue_mask(&vhost_crypto->dev, dev, idx, mask);
}
bool cryptodev_vhost_virtqueue_pending(VirtIODevice *dev,
int queue, int idx)
{
VirtIOCrypto *vcrypto = VIRTIO_CRYPTO(dev);
CryptoDevBackend *b = vcrypto->cryptodev;
CryptoDevBackendVhost *vhost_crypto;
CryptoDevBackendClient *cc;
assert(queue < MAX_CRYPTO_QUEUE_NUM);
cc = b->conf.peers.ccs[queue];
vhost_crypto = cryptodev_get_vhost(cc, b, queue);
return vhost_virtqueue_pending(&vhost_crypto->dev, idx);
}
#else
uint64_t
cryptodev_vhost_get_max_queues(CryptoDevBackendVhost *crypto)
{
return 0;
}
void cryptodev_vhost_cleanup(CryptoDevBackendVhost *crypto)
{
}
struct CryptoDevBackendVhost *
cryptodev_vhost_init(CryptoDevBackendVhostOptions *options)
{
return NULL;
}
CryptoDevBackendVhost *
cryptodev_get_vhost(CryptoDevBackendClient *cc,
CryptoDevBackend *b,
uint16_t queue)
{
return NULL;
}
int cryptodev_vhost_start(VirtIODevice *dev, int total_queues)
{
return -1;
}
void cryptodev_vhost_stop(VirtIODevice *dev, int total_queues)
{
}
void cryptodev_vhost_virtqueue_mask(VirtIODevice *dev,
int queue,
int idx, bool mask)
{
}
bool cryptodev_vhost_virtqueue_pending(VirtIODevice *dev,
int queue, int idx)
{
return false;
}
#endif