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/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
  31 /* Features supported by the host application */
  32 static const int user_feature_bits[] = {
  33     VIRTIO_F_NOTIFY_ON_EMPTY,
  34     VIRTIO_RING_F_INDIRECT_DESC,
  35     VIRTIO_RING_F_EVENT_IDX,
  36     VIRTIO_SCSI_F_HOTPLUG,
  37     VHOST_INVALID_FEATURE_BIT
  38 };
  39
  40 static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status)
  41 {
  42     VHostUserSCSI *s = (VHostUserSCSI *)vdev;
  43     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
  44     bool start = (status & VIRTIO_CONFIG_S_DRIVER_OK) && vdev->vm_running;
  45
  46     if (vsc->dev.started == start) {
  47         return;
  48     }
  49
  50     if (start) {
  51         int ret;
  52
  53         ret = vhost_scsi_common_start(vsc);
  54         if (ret < 0) {
  55             error_report("unable to start vhost-user-scsi: %s", strerror(-ret));
  56             exit(1);
  57         }
  58     } else {
  59         vhost_scsi_common_stop(vsc);
  60     }
  61 }
  62
  63 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
  64 {
  65 }
  66
  67 static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
  68 {
  69     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
  70     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
  71     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
  72     VhostUserState *user;
  73     Error *err = NULL;
  74     int ret;
  75
  76     if (!vs->conf.chardev.chr) {
  77         error_setg(errp, "vhost-user-scsi: missing chardev");
  78         return;
  79     }
  80
  81     virtio_scsi_common_realize(dev, vhost_dummy_handle_output,
  82                                vhost_dummy_handle_output,
  83                                vhost_dummy_handle_output, &err);
  84     if (err != NULL) {
  85         error_propagate(errp, err);
  86         return;
  87     }
  88
  89     user = vhost_user_init();
  90     if (!user) {
  91         error_setg(errp, "vhost-user-scsi: failed to init vhost_user");
  92         return;
  93     }
  94     user->chr = &vs->conf.chardev;
  95
  96     vsc->dev.nvqs = 2 + vs->conf.num_queues;
  97     vsc->dev.vqs = g_new(struct vhost_virtqueue, vsc->dev.nvqs);
  98     vsc->dev.vq_index = 0;
  99     vsc->dev.backend_features = 0;
 100
 101     ret = vhost_dev_init(&vsc->dev, user,
 102                          VHOST_BACKEND_TYPE_USER, 0);
 103     if (ret < 0) {
 104         error_setg(errp, "vhost-user-scsi: vhost initialization failed: %s",
 105                    strerror(-ret));
 106         vhost_user_cleanup(user);
 107         g_free(user);
 108         return;
 109     }
 110
 111     s->vhost_user = user;
 112
 113     /* Channel and lun both are 0 for bootable vhost-user-scsi disk */
 114     vsc->channel = 0;
 115     vsc->lun = 0;
 116     vsc->target = vs->conf.boot_tpgt;
 117 }
 118
 119 static void vhost_user_scsi_unrealize(DeviceState *dev, Error **errp)
 120 {
 121     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
 122     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
 123     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
 124
 125     /* This will stop the vhost backend. */
 126     vhost_user_scsi_set_status(vdev, 0);
 127
 128     vhost_dev_cleanup(&vsc->dev);
 129     g_free(vsc->dev.vqs);
 130
 131     virtio_scsi_common_unrealize(dev, errp);
 132
 133     if (s->vhost_user) {
 134         vhost_user_cleanup(s->vhost_user);
 135         g_free(s->vhost_user);
 136         s->vhost_user = NULL;
 137     }
 138 }
 139
 140 static uint64_t vhost_user_scsi_get_features(VirtIODevice *vdev,
 141                                              uint64_t features, Error **errp)
 142 {
 143     VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
 144
 145     /* Turn on predefined features supported by this device */
 146     features |= s->host_features;
 147
 148     return vhost_scsi_common_get_features(vdev, features, errp);
 149 }
 150
 151 static Property vhost_user_scsi_properties[] = {
 152     DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev),
 153     DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
 154     DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 1),
 155     DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
 156                        128),
 157     DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
 158                        0xFFFF),
 159     DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
 160     DEFINE_PROP_BIT64("hotplug", VHostUserSCSI, host_features,
 161                                                 VIRTIO_SCSI_F_HOTPLUG,
 162                                                 true),
 163     DEFINE_PROP_BIT64("param_change", VHostUserSCSI, host_features,
 164                                                      VIRTIO_SCSI_F_CHANGE,
 165                                                      true),
 166     DEFINE_PROP_END_OF_LIST(),
 167 };
 168
 169 static const VMStateDescription vmstate_vhost_scsi = {
 170     .name = "virtio-scsi",
 171     .minimum_version_id = 1,
 172     .version_id = 1,
 173     .fields = (VMStateField[]) {
 174         VMSTATE_VIRTIO_DEVICE,
 175         VMSTATE_END_OF_LIST()
 176     },
 177 };
 178
 179 static void vhost_user_scsi_class_init(ObjectClass *klass, void *data)
 180 {
 181     DeviceClass *dc = DEVICE_CLASS(klass);
 182     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 183     FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass);
 184
 185     dc->props = vhost_user_scsi_properties;
 186     dc->vmsd = &vmstate_vhost_scsi;
 187     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
 188     vdc->realize = vhost_user_scsi_realize;
 189     vdc->unrealize = vhost_user_scsi_unrealize;
 190     vdc->get_features = vhost_user_scsi_get_features;
 191     vdc->set_config = vhost_scsi_common_set_config;
 192     vdc->set_status = vhost_user_scsi_set_status;
 193     fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
 194 }
 195
 196 static void vhost_user_scsi_instance_init(Object *obj)
 197 {
 198     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj);
 199
 200     vsc->feature_bits = user_feature_bits;
 201
 202     /* Add the bootindex property for this object */
 203     device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL,
 204                                   DEVICE(vsc), NULL);
 205 }
 206
 207 static const TypeInfo vhost_user_scsi_info = {
 208     .name = TYPE_VHOST_USER_SCSI,
 209     .parent = TYPE_VHOST_SCSI_COMMON,
 210     .instance_size = sizeof(VHostUserSCSI),
 211     .class_init = vhost_user_scsi_class_init,
 212     .instance_init = vhost_user_scsi_instance_init,
 213     .interfaces = (InterfaceInfo[]) {
 214         { TYPE_FW_PATH_PROVIDER },
 215         { }
 216     },
 217 };
 218
 219 static void virtio_register_types(void)
 220 {
 221     type_register_static(&vhost_user_scsi_info);
 222 }
 223
 224 type_init(virtio_register_types)