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