hw/scsi/vhost-user-scsi.c

   1 /*
   2  * vhost-user-scsi host device
   3  *
   4  * Copyright (c) 2016 Nutanix Inc. All rights reserved.
   5  *
   6  * Author:
   7  *  Felipe Franciosi <felipe@nutanix.com>
   8  *
   9  * This work is largely based on the "vhost-scsi" implementation by:
  10  *  Stefan Hajnoczi    <stefanha@linux.vnet.ibm.com>
  11  *  Nicholas Bellinger <nab@risingtidesystems.com>
  12  *
  13  * This work is licensed under the terms of the GNU LGPL, version 2 or later.
  14  * See the COPYING.LIB file in the top-level directory.
  15  *
  16  */
  17
  18 #include "qemu/osdep.h"
  19 #include "qapi/error.h"
  20 #include "qemu/error-report.h"
  21 #include "qom/object.h"
  22 #include "hw/fw-path-provider.h"
  23 #include "hw/qdev-core.h"
  24 #include "hw/qdev-properties.h"
  25 #include "hw/virtio/vhost.h"
  26 #include "hw/virtio/vhost-backend.h"
  27 #include "hw/virtio/vhost-user-scsi.h"
  28 #include "hw/virtio/virtio.h"
  29 #include "hw/virtio/virtio-access.h"
  30 #include "chardev/char-fe.h"
  31 #include "sysemu/sysemu.h"
  32
  33 /* Features supported by the host application */
  34 static const int user_feature_bits[] = {
  35     VIRTIO_F_NOTIFY_ON_EMPTY,
  36     VIRTIO_RING_F_INDIRECT_DESC,
  37     VIRTIO_RING_F_EVENT_IDX,
  38     VIRTIO_SCSI_F_HOTPLUG,
  39     VHOST_INVALID_FEATURE_BIT
  40 };
  41
  42 enum VhostUserProtocolFeature {
  43     VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
  44 };
  45
  46 static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status)
  47 {
  48     VHostUserSCSI *s = (VHostUserSCSI *)vdev;
  49     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
  50     bool start = (status & VIRTIO_CONFIG_S_DRIVER_OK) && vdev->vm_running;
  51
  52     if (vsc->dev.started == start) {
  53         return;
  54     }
  55
  56     if (start) {
  57         int ret;
  58
  59         ret = vhost_scsi_common_start(vsc);
  60         if (ret < 0) {
  61             error_report("unable to start vhost-user-scsi: %s", strerror(-ret));
  62             exit(1);
  63         }
  64     } else {
  65         vhost_scsi_common_stop(vsc);
  66     }
  67 }
  68
  69 static void vhost_user_scsi_reset(VirtIODevice *vdev)
  70 {
  71     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev);
  72     struct vhost_dev *dev = &vsc->dev;
  73
  74     /*
  75      * Historically, reset was not implemented so only reset devices
  76      * that are expecting it.
  77      */
  78     if (!virtio_has_feature(dev->protocol_features,
  79                             VHOST_USER_PROTOCOL_F_RESET_DEVICE)) {
  80         return;
  81     }
  82
  83     if (dev->vhost_ops->vhost_reset_device) {
  84         dev->vhost_ops->vhost_reset_device(dev);
  85     }
  86 }
  87
  88 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
  89 {
  90 }
  91
  92 static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
  93 {
  94     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
  95     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
  96     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
  97     struct vhost_virtqueue *vqs = NULL;
  98     Error *err = NULL;
  99     int ret;
 100
 101     if (!vs->conf.chardev.chr) {
 102         error_setg(errp, "vhost-user-scsi: missing chardev");
 103         return;
 104     }
 105
 106     virtio_scsi_common_realize(dev, vhost_dummy_handle_output,
 107                                vhost_dummy_handle_output,
 108                                vhost_dummy_handle_output, &err);
 109     if (err != NULL) {
 110         error_propagate(errp, err);
 111         return;
 112     }
 113
 114     if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) {
 115         goto free_virtio;
 116     }
 117
 118     vsc->dev.nvqs = 2 + vs->conf.num_queues;
 119     vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs);
 120     vsc->dev.vq_index = 0;
 121     vsc->dev.backend_features = 0;
 122     vqs = vsc->dev.vqs;
 123
 124     ret = vhost_dev_init(&vsc->dev, &s->vhost_user,
 125                          VHOST_BACKEND_TYPE_USER, 0);
 126     if (ret < 0) {
 127         error_setg(errp, "vhost-user-scsi: vhost initialization failed: %s",
 128                    strerror(-ret));
 129         goto free_vhost;
 130     }
 131
 132     /* Channel and lun both are 0 for bootable vhost-user-scsi disk */
 133     vsc->channel = 0;
 134     vsc->lun = 0;
 135     vsc->target = vs->conf.boot_tpgt;
 136
 137     return;
 138
 139 free_vhost:
 140     vhost_user_cleanup(&s->vhost_user);
 141     g_free(vqs);
 142 free_virtio:
 143     virtio_scsi_common_unrealize(dev);
 144 }
 145
 146 static void vhost_user_scsi_unrealize(DeviceState *dev)
 147 {
 148     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
 149     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
 150     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
 151     struct vhost_virtqueue *vqs = vsc->dev.vqs;
 152
 153     /* This will stop the vhost backend. */
 154     vhost_user_scsi_set_status(vdev, 0);
 155
 156     vhost_dev_cleanup(&vsc->dev);
 157     g_free(vqs);
 158
 159     virtio_scsi_common_unrealize(dev);
 160     vhost_user_cleanup(&s->vhost_user);
 161 }
 162
 163 static Property vhost_user_scsi_properties[] = {
 164     DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev),
 165     DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
 166     DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 1),
 167     DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
 168                        128),
 169     DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
 170                        0xFFFF),
 171     DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
 172     DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features,
 173                                                   VIRTIO_SCSI_F_HOTPLUG,
 174                                                   true),
 175     DEFINE_PROP_BIT64("param_change", VHostSCSICommon, host_features,
 176                                                        VIRTIO_SCSI_F_CHANGE,
 177                                                        true),
 178     DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features,
 179                                                  VIRTIO_SCSI_F_T10_PI,
 180                                                  false),
 181     DEFINE_PROP_END_OF_LIST(),
 182 };
 183
 184 static const VMStateDescription vmstate_vhost_scsi = {
 185     .name = "virtio-scsi",
 186     .minimum_version_id = 1,
 187     .version_id = 1,
 188     .fields = (VMStateField[]) {
 189         VMSTATE_VIRTIO_DEVICE,
 190         VMSTATE_END_OF_LIST()
 191     },
 192 };
 193
 194 static void vhost_user_scsi_class_init(ObjectClass *klass, void *data)
 195 {
 196     DeviceClass *dc = DEVICE_CLASS(klass);
 197     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 198     FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass);
 199
 200     device_class_set_props(dc, vhost_user_scsi_properties);
 201     dc->vmsd = &vmstate_vhost_scsi;
 202     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
 203     vdc->realize = vhost_user_scsi_realize;
 204     vdc->unrealize = vhost_user_scsi_unrealize;
 205     vdc->get_features = vhost_scsi_common_get_features;
 206     vdc->set_config = vhost_scsi_common_set_config;
 207     vdc->set_status = vhost_user_scsi_set_status;
 208     vdc->reset = vhost_user_scsi_reset;
 209     fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
 210 }
 211
 212 static void vhost_user_scsi_instance_init(Object *obj)
 213 {
 214     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj);
 215
 216     vsc->feature_bits = user_feature_bits;
 217
 218     /* Add the bootindex property for this object */
 219     device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL,
 220                                   DEVICE(vsc));
 221 }
 222
 223 static const TypeInfo vhost_user_scsi_info = {
 224     .name = TYPE_VHOST_USER_SCSI,
 225     .parent = TYPE_VHOST_SCSI_COMMON,
 226     .instance_size = sizeof(VHostUserSCSI),
 227     .class_init = vhost_user_scsi_class_init,
 228     .instance_init = vhost_user_scsi_instance_init,
 229     .interfaces = (InterfaceInfo[]) {
 230         { TYPE_FW_PATH_PROVIDER },
 231         { }
 232     },
 233 };
 234
 235 static void virtio_register_types(void)
 236 {
 237     type_register_static(&vhost_user_scsi_info);
 238 }
 239
 240 type_init(virtio_register_types)