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     Error *err = NULL;
  73     int ret;
  74
  75     if (!vs->conf.chardev.chr) {
  76         error_setg(errp, "vhost-user-scsi: missing chardev");
  77         return;
  78     }
  79
  80     virtio_scsi_common_realize(dev, vhost_dummy_handle_output,
  81                                vhost_dummy_handle_output,
  82                                vhost_dummy_handle_output, &err);
  83     if (err != NULL) {
  84         error_propagate(errp, err);
  85         return;
  86     }
  87
  88     vsc->dev.nvqs = 2 + vs->conf.num_queues;
  89     vsc->dev.vqs = g_new(struct vhost_virtqueue, vsc->dev.nvqs);
  90     vsc->dev.vq_index = 0;
  91     vsc->dev.backend_features = 0;
  92
  93     ret = vhost_dev_init(&vsc->dev, (void *)&vs->conf.chardev,
  94                          VHOST_BACKEND_TYPE_USER, 0);
  95     if (ret < 0) {
  96         error_setg(errp, "vhost-user-scsi: vhost initialization failed: %s",
  97                    strerror(-ret));
  98         return;
  99     }
 100
 101     /* Channel and lun both are 0 for bootable vhost-user-scsi disk */
 102     vsc->channel = 0;
 103     vsc->lun = 0;
 104     vsc->target = vs->conf.boot_tpgt;
 105 }
 106
 107 static void vhost_user_scsi_unrealize(DeviceState *dev, Error **errp)
 108 {
 109     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
 110     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
 111     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
 112
 113     /* This will stop the vhost backend. */
 114     vhost_user_scsi_set_status(vdev, 0);
 115
 116     vhost_dev_cleanup(&vsc->dev);
 117     g_free(vsc->dev.vqs);
 118
 119     virtio_scsi_common_unrealize(dev, errp);
 120 }
 121
 122 static uint64_t vhost_user_scsi_get_features(VirtIODevice *vdev,
 123                                              uint64_t features, Error **errp)
 124 {
 125     VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
 126
 127     /* Turn on predefined features supported by this device */
 128     features |= s->host_features;
 129
 130     return vhost_scsi_common_get_features(vdev, features, errp);
 131 }
 132
 133 static Property vhost_user_scsi_properties[] = {
 134     DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev),
 135     DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
 136     DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 1),
 137     DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
 138                        128),
 139     DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
 140                        0xFFFF),
 141     DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
 142     DEFINE_PROP_BIT64("hotplug", VHostUserSCSI, host_features,
 143                                                 VIRTIO_SCSI_F_HOTPLUG,
 144                                                 true),
 145     DEFINE_PROP_BIT64("param_change", VHostUserSCSI, host_features,
 146                                                      VIRTIO_SCSI_F_CHANGE,
 147                                                      true),
 148     DEFINE_PROP_END_OF_LIST(),
 149 };
 150
 151 static const VMStateDescription vmstate_vhost_scsi = {
 152     .name = "virtio-scsi",
 153     .minimum_version_id = 1,
 154     .version_id = 1,
 155     .fields = (VMStateField[]) {
 156         VMSTATE_VIRTIO_DEVICE,
 157         VMSTATE_END_OF_LIST()
 158     },
 159 };
 160
 161 static void vhost_user_scsi_class_init(ObjectClass *klass, void *data)
 162 {
 163     DeviceClass *dc = DEVICE_CLASS(klass);
 164     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 165     FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass);
 166
 167     dc->props = vhost_user_scsi_properties;
 168     dc->vmsd = &vmstate_vhost_scsi;
 169     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
 170     vdc->realize = vhost_user_scsi_realize;
 171     vdc->unrealize = vhost_user_scsi_unrealize;
 172     vdc->get_features = vhost_user_scsi_get_features;
 173     vdc->set_config = vhost_scsi_common_set_config;
 174     vdc->set_status = vhost_user_scsi_set_status;
 175     fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
 176 }
 177
 178 static void vhost_user_scsi_instance_init(Object *obj)
 179 {
 180     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj);
 181
 182     vsc->feature_bits = user_feature_bits;
 183
 184     /* Add the bootindex property for this object */
 185     device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL,
 186                                   DEVICE(vsc), NULL);
 187 }
 188
 189 static const TypeInfo vhost_user_scsi_info = {
 190     .name = TYPE_VHOST_USER_SCSI,
 191     .parent = TYPE_VHOST_SCSI_COMMON,
 192     .instance_size = sizeof(VHostUserSCSI),
 193     .class_init = vhost_user_scsi_class_init,
 194     .instance_init = vhost_user_scsi_instance_init,
 195     .interfaces = (InterfaceInfo[]) {
 196         { TYPE_FW_PATH_PROVIDER },
 197         { }
 198     },
 199 };
 200
 201 static void virtio_register_types(void)
 202 {
 203     type_register_static(&vhost_user_scsi_info);
 204 }
 205
 206 type_init(virtio_register_types)