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