xref: /openbmc/qemu/hw/scsi/vhost-user-scsi.c (revision ffe98631)
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     VIRTIO_F_RING_RESET,
40     VHOST_INVALID_FEATURE_BIT
41 };
42 
43 enum VhostUserProtocolFeature {
44     VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
45 };
46 
47 static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status)
48 {
49     VHostUserSCSI *s = (VHostUserSCSI *)vdev;
50     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
51     bool start = (status & VIRTIO_CONFIG_S_DRIVER_OK) && vdev->vm_running;
52 
53     if (vhost_dev_is_started(&vsc->dev) == start) {
54         return;
55     }
56 
57     if (start) {
58         int ret;
59 
60         ret = vhost_scsi_common_start(vsc);
61         if (ret < 0) {
62             error_report("unable to start vhost-user-scsi: %s", strerror(-ret));
63             exit(1);
64         }
65     } else {
66         vhost_scsi_common_stop(vsc);
67     }
68 }
69 
70 static void vhost_user_scsi_reset(VirtIODevice *vdev)
71 {
72     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev);
73     struct vhost_dev *dev = &vsc->dev;
74 
75     /*
76      * Historically, reset was not implemented so only reset devices
77      * that are expecting it.
78      */
79     if (!virtio_has_feature(dev->protocol_features,
80                             VHOST_USER_PROTOCOL_F_RESET_DEVICE)) {
81         return;
82     }
83 
84     if (dev->vhost_ops->vhost_reset_device) {
85         dev->vhost_ops->vhost_reset_device(dev);
86     }
87 }
88 
89 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
90 {
91 }
92 
93 static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
94 {
95     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
96     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
97     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
98     struct vhost_virtqueue *vqs = NULL;
99     Error *err = NULL;
100     int ret;
101 
102     if (!vs->conf.chardev.chr) {
103         error_setg(errp, "vhost-user-scsi: missing chardev");
104         return;
105     }
106 
107     virtio_scsi_common_realize(dev, vhost_dummy_handle_output,
108                                vhost_dummy_handle_output,
109                                vhost_dummy_handle_output, &err);
110     if (err != NULL) {
111         error_propagate(errp, err);
112         return;
113     }
114 
115     if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) {
116         goto free_virtio;
117     }
118 
119     vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
120     vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs);
121     vsc->dev.vq_index = 0;
122     vsc->dev.backend_features = 0;
123     vqs = vsc->dev.vqs;
124 
125     ret = vhost_dev_init(&vsc->dev, &s->vhost_user,
126                          VHOST_BACKEND_TYPE_USER, 0, errp);
127     if (ret < 0) {
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,
166                        VIRTIO_SCSI_AUTO_NUM_QUEUES),
167     DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
168                        128),
169     DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
170                        0xFFFF),
171     DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
172     DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features,
173                                                   VIRTIO_SCSI_F_HOTPLUG,
174                                                   true),
175     DEFINE_PROP_BIT64("param_change", VHostSCSICommon, host_features,
176                                                        VIRTIO_SCSI_F_CHANGE,
177                                                        true),
178     DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features,
179                                                  VIRTIO_SCSI_F_T10_PI,
180                                                  false),
181     DEFINE_PROP_END_OF_LIST(),
182 };
183 
184 static const VMStateDescription vmstate_vhost_scsi = {
185     .name = "virtio-scsi",
186     .minimum_version_id = 1,
187     .version_id = 1,
188     .fields = (VMStateField[]) {
189         VMSTATE_VIRTIO_DEVICE,
190         VMSTATE_END_OF_LIST()
191     },
192 };
193 
194 static void vhost_user_scsi_class_init(ObjectClass *klass, void *data)
195 {
196     DeviceClass *dc = DEVICE_CLASS(klass);
197     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
198     FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass);
199 
200     device_class_set_props(dc, vhost_user_scsi_properties);
201     dc->vmsd = &vmstate_vhost_scsi;
202     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
203     vdc->realize = vhost_user_scsi_realize;
204     vdc->unrealize = vhost_user_scsi_unrealize;
205     vdc->get_features = vhost_scsi_common_get_features;
206     vdc->set_config = vhost_scsi_common_set_config;
207     vdc->set_status = vhost_user_scsi_set_status;
208     vdc->reset = vhost_user_scsi_reset;
209     fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
210 }
211 
212 static void vhost_user_scsi_instance_init(Object *obj)
213 {
214     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj);
215 
216     vsc->feature_bits = user_feature_bits;
217 
218     /* Add the bootindex property for this object */
219     device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL,
220                                   DEVICE(vsc));
221 }
222 
223 static const TypeInfo vhost_user_scsi_info = {
224     .name = TYPE_VHOST_USER_SCSI,
225     .parent = TYPE_VHOST_SCSI_COMMON,
226     .instance_size = sizeof(VHostUserSCSI),
227     .class_init = vhost_user_scsi_class_init,
228     .instance_init = vhost_user_scsi_instance_init,
229     .interfaces = (InterfaceInfo[]) {
230         { TYPE_FW_PATH_PROVIDER },
231         { }
232     },
233 };
234 
235 static void virtio_register_types(void)
236 {
237     type_register_static(&vhost_user_scsi_info);
238 }
239 
240 type_init(virtio_register_types)
241