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 "chardev/char-fe.h"
30 #include "system/system.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 VIRTIO_F_RING_RESET,
39 VIRTIO_F_IN_ORDER,
40 VIRTIO_F_NOTIFICATION_DATA,
41 VHOST_INVALID_FEATURE_BIT
42 };
43
vhost_user_scsi_start(VHostUserSCSI * s,Error ** errp)44 static int vhost_user_scsi_start(VHostUserSCSI *s, Error **errp)
45 {
46 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
47 int ret;
48
49 ret = vhost_scsi_common_start(vsc, errp);
50 s->started_vu = !(ret < 0);
51
52 return ret;
53 }
54
vhost_user_scsi_stop(VHostUserSCSI * s)55 static int vhost_user_scsi_stop(VHostUserSCSI *s)
56 {
57 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
58
59 if (!s->started_vu) {
60 return 0;
61 }
62 s->started_vu = false;
63
64 return vhost_scsi_common_stop(vsc);
65 }
66
vhost_user_scsi_set_status(VirtIODevice * vdev,uint8_t status)67 static int vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status)
68 {
69 VHostUserSCSI *s = (VHostUserSCSI *)vdev;
70 DeviceState *dev = DEVICE(vdev);
71 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
72 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
73 bool should_start = virtio_device_should_start(vdev, status);
74 Error *local_err = NULL;
75 int ret;
76
77 if (!s->connected) {
78 return -1;
79 }
80
81 if (vhost_dev_is_started(&vsc->dev) == should_start) {
82 return 0;
83 }
84
85 if (should_start) {
86 ret = vhost_user_scsi_start(s, &local_err);
87 if (ret < 0) {
88 error_reportf_err(local_err,
89 "unable to start vhost-user-scsi: %s: ",
90 strerror(-ret));
91 qemu_chr_fe_disconnect(&vs->conf.chardev);
92 }
93 } else {
94 ret = vhost_user_scsi_stop(s);
95 if (ret) {
96 return ret;
97 }
98 }
99 return 0;
100 }
101
vhost_user_scsi_handle_output(VirtIODevice * vdev,VirtQueue * vq)102 static void vhost_user_scsi_handle_output(VirtIODevice *vdev, VirtQueue *vq)
103 {
104 VHostUserSCSI *s = (VHostUserSCSI *)vdev;
105 DeviceState *dev = DEVICE(vdev);
106 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
107 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
108
109 Error *local_err = NULL;
110 int i, ret;
111
112 if (!vdev->start_on_kick) {
113 return;
114 }
115
116 if (!s->connected) {
117 return;
118 }
119
120 if (vhost_dev_is_started(&vsc->dev)) {
121 return;
122 }
123
124 /*
125 * Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
126 * vhost here instead of waiting for .set_status().
127 */
128 ret = vhost_user_scsi_start(s, &local_err);
129 if (ret < 0) {
130 error_reportf_err(local_err, "vhost-user-scsi: vhost start failed: ");
131 qemu_chr_fe_disconnect(&vs->conf.chardev);
132 return;
133 }
134
135 /* Kick right away to begin processing requests already in vring */
136 for (i = 0; i < vsc->dev.nvqs; i++) {
137 VirtQueue *kick_vq = virtio_get_queue(vdev, i);
138
139 if (!virtio_queue_get_desc_addr(vdev, i)) {
140 continue;
141 }
142 event_notifier_set(virtio_queue_get_host_notifier(kick_vq));
143 }
144 }
145
vhost_user_scsi_connect(DeviceState * dev,Error ** errp)146 static int vhost_user_scsi_connect(DeviceState *dev, Error **errp)
147 {
148 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
149 VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
150 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
151 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
152 int ret = 0;
153
154 if (s->connected) {
155 return 0;
156 }
157
158 vsc->dev.num_queues = vs->conf.num_queues;
159 vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
160 vsc->dev.vqs = s->vhost_vqs;
161 vsc->dev.vq_index = 0;
162 vsc->dev.backend_features = 0;
163
164 ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0,
165 errp);
166 if (ret < 0) {
167 return ret;
168 }
169
170 s->connected = true;
171
172 /* restore vhost state */
173 if (virtio_device_started(vdev, vdev->status)) {
174 ret = vhost_user_scsi_start(s, errp);
175 }
176
177 return ret;
178 }
179
180 static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event);
181
vhost_user_scsi_disconnect(DeviceState * dev)182 static void vhost_user_scsi_disconnect(DeviceState *dev)
183 {
184 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
185 VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
186 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
187 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
188
189 if (!s->connected) {
190 goto done;
191 }
192 s->connected = false;
193
194 vhost_user_scsi_stop(s);
195
196 vhost_dev_cleanup(&vsc->dev);
197
198 done:
199 /* Re-instate the event handler for new connections */
200 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL,
201 vhost_user_scsi_event, NULL, dev, NULL, true);
202 }
203
vhost_user_scsi_event(void * opaque,QEMUChrEvent event)204 static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event)
205 {
206 DeviceState *dev = opaque;
207 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
208 VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
209 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
210 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
211 Error *local_err = NULL;
212
213 switch (event) {
214 case CHR_EVENT_OPENED:
215 if (vhost_user_scsi_connect(dev, &local_err) < 0) {
216 error_report_err(local_err);
217 qemu_chr_fe_disconnect(&vs->conf.chardev);
218 return;
219 }
220 break;
221 case CHR_EVENT_CLOSED:
222 /* defer close until later to avoid circular close */
223 vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev,
224 vhost_user_scsi_disconnect);
225 break;
226 case CHR_EVENT_BREAK:
227 case CHR_EVENT_MUX_IN:
228 case CHR_EVENT_MUX_OUT:
229 /* Ignore */
230 break;
231 }
232 }
233
vhost_user_scsi_realize_connect(VHostUserSCSI * s,Error ** errp)234 static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp)
235 {
236 DeviceState *dev = DEVICE(s);
237 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
238 int ret;
239
240 s->connected = false;
241
242 ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp);
243 if (ret < 0) {
244 return ret;
245 }
246
247 ret = vhost_user_scsi_connect(dev, errp);
248 if (ret < 0) {
249 qemu_chr_fe_disconnect(&vs->conf.chardev);
250 return ret;
251 }
252 assert(s->connected);
253
254 return 0;
255 }
256
vhost_user_scsi_realize(DeviceState * dev,Error ** errp)257 static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
258 {
259 ERRP_GUARD();
260 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
261 VHostUserSCSI *s = VHOST_USER_SCSI(dev);
262 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
263 Error *err = NULL;
264 int ret;
265 int retries = VU_REALIZE_CONN_RETRIES;
266
267 if (!vs->conf.chardev.chr) {
268 error_setg(errp, "vhost-user-scsi: missing chardev");
269 return;
270 }
271
272 virtio_scsi_common_realize(dev, vhost_user_scsi_handle_output,
273 vhost_user_scsi_handle_output,
274 vhost_user_scsi_handle_output, &err);
275 if (err != NULL) {
276 error_propagate(errp, err);
277 return;
278 }
279
280 if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) {
281 goto free_virtio;
282 }
283
284 vsc->inflight = g_new0(struct vhost_inflight, 1);
285 s->vhost_vqs = g_new0(struct vhost_virtqueue,
286 VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues);
287
288 assert(!*errp);
289 do {
290 if (*errp) {
291 error_prepend(errp, "Reconnecting after error: ");
292 error_report_err(*errp);
293 *errp = NULL;
294 }
295 ret = vhost_user_scsi_realize_connect(s, errp);
296 } while (ret < 0 && retries--);
297
298 if (ret < 0) {
299 goto free_vhost;
300 }
301
302 /* we're fully initialized, now we can operate, so add the handler */
303 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL,
304 vhost_user_scsi_event, NULL, (void *)dev,
305 NULL, true);
306 /* Channel and lun both are 0 for bootable vhost-user-scsi disk */
307 vsc->channel = 0;
308 vsc->lun = 0;
309 vsc->target = vs->conf.boot_tpgt;
310
311 return;
312
313 free_vhost:
314 g_free(s->vhost_vqs);
315 s->vhost_vqs = NULL;
316 g_free(vsc->inflight);
317 vsc->inflight = NULL;
318 vhost_user_cleanup(&s->vhost_user);
319
320 free_virtio:
321 virtio_scsi_common_unrealize(dev);
322 }
323
vhost_user_scsi_unrealize(DeviceState * dev)324 static void vhost_user_scsi_unrealize(DeviceState *dev)
325 {
326 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
327 VHostUserSCSI *s = VHOST_USER_SCSI(dev);
328 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
329 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
330
331 /* This will stop the vhost backend. */
332 vhost_user_scsi_set_status(vdev, 0);
333 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL,
334 NULL, false);
335
336 vhost_dev_cleanup(&vsc->dev);
337 g_free(s->vhost_vqs);
338 s->vhost_vqs = NULL;
339
340 vhost_dev_free_inflight(vsc->inflight);
341 g_free(vsc->inflight);
342 vsc->inflight = NULL;
343
344 vhost_user_cleanup(&s->vhost_user);
345 virtio_scsi_common_unrealize(dev);
346 }
347
348 static const Property vhost_user_scsi_properties[] = {
349 DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev),
350 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
351 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues,
352 VIRTIO_SCSI_AUTO_NUM_QUEUES),
353 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
354 128),
355 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
356 0xFFFF),
357 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
358 DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features,
359 VIRTIO_SCSI_F_HOTPLUG,
360 true),
361 DEFINE_PROP_BIT64("param_change", VHostSCSICommon, host_features,
362 VIRTIO_SCSI_F_CHANGE,
363 true),
364 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features,
365 VIRTIO_SCSI_F_T10_PI,
366 false),
367 };
368
vhost_user_scsi_reset(VirtIODevice * vdev)369 static void vhost_user_scsi_reset(VirtIODevice *vdev)
370 {
371 VHostUserSCSI *s = VHOST_USER_SCSI(vdev);
372 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
373
374 vhost_dev_free_inflight(vsc->inflight);
375 }
376
vhost_user_scsi_get_vhost(VirtIODevice * vdev)377 static struct vhost_dev *vhost_user_scsi_get_vhost(VirtIODevice *vdev)
378 {
379 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev);
380 return &vsc->dev;
381 }
382
383 static const VMStateDescription vmstate_vhost_scsi = {
384 .name = "virtio-scsi",
385 .minimum_version_id = 1,
386 .version_id = 1,
387 .fields = (const VMStateField[]) {
388 VMSTATE_VIRTIO_DEVICE,
389 VMSTATE_END_OF_LIST()
390 },
391 };
392
vhost_user_scsi_class_init(ObjectClass * klass,const void * data)393 static void vhost_user_scsi_class_init(ObjectClass *klass, const void *data)
394 {
395 DeviceClass *dc = DEVICE_CLASS(klass);
396 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
397 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass);
398
399 device_class_set_props(dc, vhost_user_scsi_properties);
400 dc->vmsd = &vmstate_vhost_scsi;
401 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
402 vdc->realize = vhost_user_scsi_realize;
403 vdc->unrealize = vhost_user_scsi_unrealize;
404 vdc->get_features = vhost_scsi_common_get_features;
405 vdc->set_config = vhost_scsi_common_set_config;
406 vdc->set_status = vhost_user_scsi_set_status;
407 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
408 vdc->reset = vhost_user_scsi_reset;
409 vdc->get_vhost = vhost_user_scsi_get_vhost;
410 }
411
vhost_user_scsi_instance_init(Object * obj)412 static void vhost_user_scsi_instance_init(Object *obj)
413 {
414 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj);
415
416 vsc->feature_bits = user_feature_bits;
417
418 /* Add the bootindex property for this object */
419 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL,
420 DEVICE(vsc));
421 }
422
423 static const TypeInfo vhost_user_scsi_info = {
424 .name = TYPE_VHOST_USER_SCSI,
425 .parent = TYPE_VHOST_SCSI_COMMON,
426 .instance_size = sizeof(VHostUserSCSI),
427 .class_init = vhost_user_scsi_class_init,
428 .instance_init = vhost_user_scsi_instance_init,
429 .interfaces = (const InterfaceInfo[]) {
430 { TYPE_FW_PATH_PROVIDER },
431 { }
432 },
433 };
434
virtio_register_types(void)435 static void virtio_register_types(void)
436 {
437 type_register_static(&vhost_user_scsi_info);
438 }
439
440 type_init(virtio_register_types)
441