xref: /openbmc/qemu/hw/scsi/vhost-user-scsi.c (revision 6c187695)
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/qdev-properties-system.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 #include "sysemu/sysemu.h"
32 
33 /* Features supported by the host application */
34 static const int user_feature_bits[] = {
35     VIRTIO_F_NOTIFY_ON_EMPTY,
36     VIRTIO_RING_F_INDIRECT_DESC,
37     VIRTIO_RING_F_EVENT_IDX,
38     VIRTIO_SCSI_F_HOTPLUG,
39     VHOST_INVALID_FEATURE_BIT
40 };
41 
42 enum VhostUserProtocolFeature {
43     VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
44 };
45 
46 static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status)
47 {
48     VHostUserSCSI *s = (VHostUserSCSI *)vdev;
49     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
50     bool start = (status & VIRTIO_CONFIG_S_DRIVER_OK) && vdev->vm_running;
51 
52     if (vhost_dev_is_started(&vsc->dev) == start) {
53         return;
54     }
55 
56     if (start) {
57         int ret;
58 
59         ret = vhost_scsi_common_start(vsc);
60         if (ret < 0) {
61             error_report("unable to start vhost-user-scsi: %s", strerror(-ret));
62             exit(1);
63         }
64     } else {
65         vhost_scsi_common_stop(vsc);
66     }
67 }
68 
69 static void vhost_user_scsi_reset(VirtIODevice *vdev)
70 {
71     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev);
72     struct vhost_dev *dev = &vsc->dev;
73 
74     /*
75      * Historically, reset was not implemented so only reset devices
76      * that are expecting it.
77      */
78     if (!virtio_has_feature(dev->protocol_features,
79                             VHOST_USER_PROTOCOL_F_RESET_DEVICE)) {
80         return;
81     }
82 
83     if (dev->vhost_ops->vhost_reset_device) {
84         dev->vhost_ops->vhost_reset_device(dev);
85     }
86 }
87 
88 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
89 {
90 }
91 
92 static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
93 {
94     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
95     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
96     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
97     struct vhost_virtqueue *vqs = NULL;
98     Error *err = NULL;
99     int ret;
100 
101     if (!vs->conf.chardev.chr) {
102         error_setg(errp, "vhost-user-scsi: missing chardev");
103         return;
104     }
105 
106     virtio_scsi_common_realize(dev, vhost_dummy_handle_output,
107                                vhost_dummy_handle_output,
108                                vhost_dummy_handle_output, &err);
109     if (err != NULL) {
110         error_propagate(errp, err);
111         return;
112     }
113 
114     if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) {
115         goto free_virtio;
116     }
117 
118     vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
119     vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs);
120     vsc->dev.vq_index = 0;
121     vsc->dev.backend_features = 0;
122     vqs = vsc->dev.vqs;
123 
124     ret = vhost_dev_init(&vsc->dev, &s->vhost_user,
125                          VHOST_BACKEND_TYPE_USER, 0, errp);
126     if (ret < 0) {
127         goto free_vhost;
128     }
129 
130     /* Channel and lun both are 0 for bootable vhost-user-scsi disk */
131     vsc->channel = 0;
132     vsc->lun = 0;
133     vsc->target = vs->conf.boot_tpgt;
134 
135     return;
136 
137 free_vhost:
138     vhost_user_cleanup(&s->vhost_user);
139     g_free(vqs);
140 free_virtio:
141     virtio_scsi_common_unrealize(dev);
142 }
143 
144 static void vhost_user_scsi_unrealize(DeviceState *dev)
145 {
146     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
147     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
148     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
149     struct vhost_virtqueue *vqs = vsc->dev.vqs;
150 
151     /* This will stop the vhost backend. */
152     vhost_user_scsi_set_status(vdev, 0);
153 
154     vhost_dev_cleanup(&vsc->dev);
155     g_free(vqs);
156 
157     virtio_scsi_common_unrealize(dev);
158     vhost_user_cleanup(&s->vhost_user);
159 }
160 
161 static Property vhost_user_scsi_properties[] = {
162     DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev),
163     DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
164     DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues,
165                        VIRTIO_SCSI_AUTO_NUM_QUEUES),
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