xref: /openbmc/qemu/hw/scsi/vhost-user-scsi.c (revision 58ea30f5) 
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     if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) {
89         return;
90     }
91 
92     vsc->dev.nvqs = 2 + vs->conf.num_queues;
93     vsc->dev.vqs = g_new(struct vhost_virtqueue, vsc->dev.nvqs);
94     vsc->dev.vq_index = 0;
95     vsc->dev.backend_features = 0;
96 
97     ret = vhost_dev_init(&vsc->dev, &s->vhost_user,
98                          VHOST_BACKEND_TYPE_USER, 0);
99     if (ret < 0) {
100         error_setg(errp, "vhost-user-scsi: vhost initialization failed: %s",
101                    strerror(-ret));
102         vhost_user_cleanup(&s->vhost_user);
103         return;
104     }
105 
106     /* Channel and lun both are 0 for bootable vhost-user-scsi disk */
107     vsc->channel = 0;
108     vsc->lun = 0;
109     vsc->target = vs->conf.boot_tpgt;
110 }
111 
112 static void vhost_user_scsi_unrealize(DeviceState *dev, Error **errp)
113 {
114     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
115     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
116     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
117     struct vhost_virtqueue *vqs = vsc->dev.vqs;
118 
119     /* This will stop the vhost backend. */
120     vhost_user_scsi_set_status(vdev, 0);
121 
122     vhost_dev_cleanup(&vsc->dev);
123     g_free(vqs);
124 
125     virtio_scsi_common_unrealize(dev, errp);
126     vhost_user_cleanup(&s->vhost_user);
127 }
128 
129 static Property vhost_user_scsi_properties[] = {
130     DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev),
131     DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
132     DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 1),
133     DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
134                        128),
135     DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
136                        0xFFFF),
137     DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
138     DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features,
139                                                   VIRTIO_SCSI_F_HOTPLUG,
140                                                   true),
141     DEFINE_PROP_BIT64("param_change", VHostSCSICommon, host_features,
142                                                        VIRTIO_SCSI_F_CHANGE,
143                                                        true),
144     DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features,
145                                                  VIRTIO_SCSI_F_T10_PI,
146                                                  false),
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_scsi_common_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)
206