qemu/hw/scsi/vhost-user-scsi.c
Richard Henderson 2d7b39a64f hw/scsi: Constify VMState
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231221031652.119827-52-richard.henderson@linaro.org>
2023-12-30 07:38:06 +11:00

436 lines
12 KiB
C

/*
* vhost-user-scsi host device
*
* Copyright (c) 2016 Nutanix Inc. All rights reserved.
*
* Author:
* Felipe Franciosi <felipe@nutanix.com>
*
* This work is largely based on the "vhost-scsi" implementation by:
* Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
* Nicholas Bellinger <nab@risingtidesystems.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "hw/fw-path-provider.h"
#include "hw/qdev-core.h"
#include "hw/qdev-properties.h"
#include "hw/qdev-properties-system.h"
#include "hw/virtio/vhost.h"
#include "hw/virtio/vhost-backend.h"
#include "hw/virtio/vhost-user-scsi.h"
#include "hw/virtio/virtio.h"
#include "chardev/char-fe.h"
#include "sysemu/sysemu.h"
/* Features supported by the host application */
static const int user_feature_bits[] = {
VIRTIO_F_NOTIFY_ON_EMPTY,
VIRTIO_RING_F_INDIRECT_DESC,
VIRTIO_RING_F_EVENT_IDX,
VIRTIO_SCSI_F_HOTPLUG,
VIRTIO_F_RING_RESET,
VHOST_INVALID_FEATURE_BIT
};
static int vhost_user_scsi_start(VHostUserSCSI *s, Error **errp)
{
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
int ret;
ret = vhost_scsi_common_start(vsc, errp);
s->started_vu = !(ret < 0);
return ret;
}
static void vhost_user_scsi_stop(VHostUserSCSI *s)
{
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
if (!s->started_vu) {
return;
}
s->started_vu = false;
vhost_scsi_common_stop(vsc);
}
static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status)
{
VHostUserSCSI *s = (VHostUserSCSI *)vdev;
DeviceState *dev = DEVICE(vdev);
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
bool should_start = virtio_device_should_start(vdev, status);
Error *local_err = NULL;
int ret;
if (!s->connected) {
return;
}
if (vhost_dev_is_started(&vsc->dev) == should_start) {
return;
}
if (should_start) {
ret = vhost_user_scsi_start(s, &local_err);
if (ret < 0) {
error_reportf_err(local_err,
"unable to start vhost-user-scsi: %s: ",
strerror(-ret));
qemu_chr_fe_disconnect(&vs->conf.chardev);
}
} else {
vhost_user_scsi_stop(s);
}
}
static void vhost_user_scsi_handle_output(VirtIODevice *vdev, VirtQueue *vq)
{
VHostUserSCSI *s = (VHostUserSCSI *)vdev;
DeviceState *dev = DEVICE(vdev);
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
Error *local_err = NULL;
int i, ret;
if (!vdev->start_on_kick) {
return;
}
if (!s->connected) {
return;
}
if (vhost_dev_is_started(&vsc->dev)) {
return;
}
/*
* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
* vhost here instead of waiting for .set_status().
*/
ret = vhost_user_scsi_start(s, &local_err);
if (ret < 0) {
error_reportf_err(local_err, "vhost-user-scsi: vhost start failed: ");
qemu_chr_fe_disconnect(&vs->conf.chardev);
return;
}
/* Kick right away to begin processing requests already in vring */
for (i = 0; i < vsc->dev.nvqs; i++) {
VirtQueue *kick_vq = virtio_get_queue(vdev, i);
if (!virtio_queue_get_desc_addr(vdev, i)) {
continue;
}
event_notifier_set(virtio_queue_get_host_notifier(kick_vq));
}
}
static int vhost_user_scsi_connect(DeviceState *dev, Error **errp)
{
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
int ret = 0;
if (s->connected) {
return 0;
}
vsc->dev.num_queues = vs->conf.num_queues;
vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
vsc->dev.vqs = s->vhost_vqs;
vsc->dev.vq_index = 0;
vsc->dev.backend_features = 0;
ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0,
errp);
if (ret < 0) {
return ret;
}
s->connected = true;
/* restore vhost state */
if (virtio_device_started(vdev, vdev->status)) {
ret = vhost_user_scsi_start(s, errp);
}
return ret;
}
static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event);
static void vhost_user_scsi_disconnect(DeviceState *dev)
{
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
if (!s->connected) {
return;
}
s->connected = false;
vhost_user_scsi_stop(s);
vhost_dev_cleanup(&vsc->dev);
/* Re-instate the event handler for new connections */
qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL,
vhost_user_scsi_event, NULL, dev, NULL, true);
}
static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event)
{
DeviceState *dev = opaque;
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
Error *local_err = NULL;
switch (event) {
case CHR_EVENT_OPENED:
if (vhost_user_scsi_connect(dev, &local_err) < 0) {
error_report_err(local_err);
qemu_chr_fe_disconnect(&vs->conf.chardev);
return;
}
break;
case CHR_EVENT_CLOSED:
/* defer close until later to avoid circular close */
vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev,
vhost_user_scsi_disconnect,
vhost_user_scsi_event);
break;
case CHR_EVENT_BREAK:
case CHR_EVENT_MUX_IN:
case CHR_EVENT_MUX_OUT:
/* Ignore */
break;
}
}
static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp)
{
DeviceState *dev = DEVICE(s);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
int ret;
s->connected = false;
ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp);
if (ret < 0) {
return ret;
}
ret = vhost_user_scsi_connect(dev, errp);
if (ret < 0) {
qemu_chr_fe_disconnect(&vs->conf.chardev);
return ret;
}
assert(s->connected);
return 0;
}
static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
{
ERRP_GUARD();
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
VHostUserSCSI *s = VHOST_USER_SCSI(dev);
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
Error *err = NULL;
int ret;
int retries = VU_REALIZE_CONN_RETRIES;
if (!vs->conf.chardev.chr) {
error_setg(errp, "vhost-user-scsi: missing chardev");
return;
}
virtio_scsi_common_realize(dev, vhost_user_scsi_handle_output,
vhost_user_scsi_handle_output,
vhost_user_scsi_handle_output, &err);
if (err != NULL) {
error_propagate(errp, err);
return;
}
if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) {
goto free_virtio;
}
vsc->inflight = g_new0(struct vhost_inflight, 1);
s->vhost_vqs = g_new0(struct vhost_virtqueue,
VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues);
assert(!*errp);
do {
if (*errp) {
error_prepend(errp, "Reconnecting after error: ");
error_report_err(*errp);
*errp = NULL;
}
ret = vhost_user_scsi_realize_connect(s, errp);
} while (ret < 0 && retries--);
if (ret < 0) {
goto free_vhost;
}
/* we're fully initialized, now we can operate, so add the handler */
qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL,
vhost_user_scsi_event, NULL, (void *)dev,
NULL, true);
/* Channel and lun both are 0 for bootable vhost-user-scsi disk */
vsc->channel = 0;
vsc->lun = 0;
vsc->target = vs->conf.boot_tpgt;
return;
free_vhost:
g_free(s->vhost_vqs);
s->vhost_vqs = NULL;
g_free(vsc->inflight);
vsc->inflight = NULL;
vhost_user_cleanup(&s->vhost_user);
free_virtio:
virtio_scsi_common_unrealize(dev);
}
static void vhost_user_scsi_unrealize(DeviceState *dev)
{
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
VHostUserSCSI *s = VHOST_USER_SCSI(dev);
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
/* This will stop the vhost backend. */
vhost_user_scsi_set_status(vdev, 0);
qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL,
NULL, false);
vhost_dev_cleanup(&vsc->dev);
g_free(s->vhost_vqs);
s->vhost_vqs = NULL;
vhost_dev_free_inflight(vsc->inflight);
g_free(vsc->inflight);
vsc->inflight = NULL;
vhost_user_cleanup(&s->vhost_user);
virtio_scsi_common_unrealize(dev);
}
static Property vhost_user_scsi_properties[] = {
DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev),
DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues,
VIRTIO_SCSI_AUTO_NUM_QUEUES),
DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
128),
DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
0xFFFF),
DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features,
VIRTIO_SCSI_F_HOTPLUG,
true),
DEFINE_PROP_BIT64("param_change", VHostSCSICommon, host_features,
VIRTIO_SCSI_F_CHANGE,
true),
DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features,
VIRTIO_SCSI_F_T10_PI,
false),
DEFINE_PROP_END_OF_LIST(),
};
static void vhost_user_scsi_reset(VirtIODevice *vdev)
{
VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
vhost_dev_free_inflight(vsc->inflight);
}
static struct vhost_dev *vhost_user_scsi_get_vhost(VirtIODevice *vdev)
{
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev);
return &vsc->dev;
}
static const VMStateDescription vmstate_vhost_scsi = {
.name = "virtio-scsi",
.minimum_version_id = 1,
.version_id = 1,
.fields = (const VMStateField[]) {
VMSTATE_VIRTIO_DEVICE,
VMSTATE_END_OF_LIST()
},
};
static void vhost_user_scsi_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass);
device_class_set_props(dc, vhost_user_scsi_properties);
dc->vmsd = &vmstate_vhost_scsi;
set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
vdc->realize = vhost_user_scsi_realize;
vdc->unrealize = vhost_user_scsi_unrealize;
vdc->get_features = vhost_scsi_common_get_features;
vdc->set_config = vhost_scsi_common_set_config;
vdc->set_status = vhost_user_scsi_set_status;
fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
vdc->reset = vhost_user_scsi_reset;
vdc->get_vhost = vhost_user_scsi_get_vhost;
}
static void vhost_user_scsi_instance_init(Object *obj)
{
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj);
vsc->feature_bits = user_feature_bits;
/* Add the bootindex property for this object */
device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL,
DEVICE(vsc));
}
static const TypeInfo vhost_user_scsi_info = {
.name = TYPE_VHOST_USER_SCSI,
.parent = TYPE_VHOST_SCSI_COMMON,
.instance_size = sizeof(VHostUserSCSI),
.class_init = vhost_user_scsi_class_init,
.instance_init = vhost_user_scsi_instance_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_FW_PATH_PROVIDER },
{ }
},
};
static void virtio_register_types(void)
{
type_register_static(&vhost_user_scsi_info);
}
type_init(virtio_register_types)