xref: /openbmc/qemu/hw/scsi/vhost-user-scsi.c (revision 25b1d45a) 
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)
225