xref: /openbmc/qemu/hw/scsi/vhost-user-scsi.c (revision 354908ce)
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)
240