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