1 /*
2 * vhost_scsi host device
3 *
4 * Copyright IBM, Corp. 2011
5 *
6 * Authors:
7 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
8 *
9 * Changes for QEMU mainline + tcm_vhost kernel upstream:
10 * Nicholas Bellinger <nab@risingtidesystems.com>
11 *
12 * This work is licensed under the terms of the GNU LGPL, version 2 or later.
13 * See the COPYING.LIB file in the top-level directory.
14 *
15 */
16
17 #include "qemu/osdep.h"
18 #include <linux/vhost.h>
19 #include <sys/ioctl.h>
20 #include "qapi/error.h"
21 #include "qemu/error-report.h"
22 #include "qemu/module.h"
23 #include "monitor/monitor.h"
24 #include "migration/blocker.h"
25 #include "hw/virtio/vhost-scsi.h"
26 #include "hw/virtio/vhost.h"
27 #include "hw/virtio/virtio-scsi.h"
28 #include "hw/virtio/virtio-bus.h"
29 #include "hw/fw-path-provider.h"
30 #include "hw/qdev-properties.h"
31 #include "qemu/cutils.h"
32 #include "sysemu/sysemu.h"
33
34 /* Features supported by host kernel. */
35 static const int kernel_feature_bits[] = {
36 VIRTIO_F_NOTIFY_ON_EMPTY,
37 VIRTIO_RING_F_INDIRECT_DESC,
38 VIRTIO_RING_F_EVENT_IDX,
39 VIRTIO_SCSI_F_HOTPLUG,
40 VIRTIO_F_RING_RESET,
41 VHOST_INVALID_FEATURE_BIT
42 };
43
vhost_scsi_set_endpoint(VHostSCSI * s)44 static int vhost_scsi_set_endpoint(VHostSCSI *s)
45 {
46 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
47 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
48 const VhostOps *vhost_ops = vsc->dev.vhost_ops;
49 struct vhost_scsi_target backend;
50 int ret;
51
52 memset(&backend, 0, sizeof(backend));
53 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn);
54 ret = vhost_ops->vhost_scsi_set_endpoint(&vsc->dev, &backend);
55 if (ret < 0) {
56 return -errno;
57 }
58 return 0;
59 }
60
vhost_scsi_clear_endpoint(VHostSCSI * s)61 static void vhost_scsi_clear_endpoint(VHostSCSI *s)
62 {
63 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
64 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
65 struct vhost_scsi_target backend;
66 const VhostOps *vhost_ops = vsc->dev.vhost_ops;
67
68 memset(&backend, 0, sizeof(backend));
69 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn);
70 vhost_ops->vhost_scsi_clear_endpoint(&vsc->dev, &backend);
71 }
72
vhost_scsi_start(VHostSCSI * s)73 static int vhost_scsi_start(VHostSCSI *s)
74 {
75 int ret, abi_version;
76 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
77 const VhostOps *vhost_ops = vsc->dev.vhost_ops;
78 Error *local_err = NULL;
79
80 ret = vhost_ops->vhost_scsi_get_abi_version(&vsc->dev, &abi_version);
81 if (ret < 0) {
82 return -errno;
83 }
84 if (abi_version > VHOST_SCSI_ABI_VERSION) {
85 error_report("vhost-scsi: The running tcm_vhost kernel abi_version:"
86 " %d is greater than vhost_scsi userspace supports: %d,"
87 " please upgrade your version of QEMU", abi_version,
88 VHOST_SCSI_ABI_VERSION);
89 return -ENOSYS;
90 }
91
92 ret = vhost_scsi_common_start(vsc, &local_err);
93 if (ret < 0) {
94 error_reportf_err(local_err, "Error starting vhost-scsi");
95 return ret;
96 }
97
98 ret = vhost_scsi_set_endpoint(s);
99 if (ret < 0) {
100 error_reportf_err(local_err, "Error setting vhost-scsi endpoint");
101 vhost_scsi_common_stop(vsc);
102 }
103
104 return ret;
105 }
106
vhost_scsi_stop(VHostSCSI * s)107 static void vhost_scsi_stop(VHostSCSI *s)
108 {
109 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
110
111 vhost_scsi_clear_endpoint(s);
112 vhost_scsi_common_stop(vsc);
113 }
114
vhost_scsi_set_status(VirtIODevice * vdev,uint8_t val)115 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val)
116 {
117 VHostSCSI *s = VHOST_SCSI(vdev);
118 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
119 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK);
120
121 if (!vdev->vm_running) {
122 start = false;
123 }
124
125 if (vhost_dev_is_started(&vsc->dev) == start) {
126 return;
127 }
128
129 if (start) {
130 int ret;
131
132 ret = vhost_scsi_start(s);
133 if (ret < 0) {
134 error_report("unable to start vhost-scsi: %s", strerror(-ret));
135 exit(1);
136 }
137 } else {
138 vhost_scsi_stop(s);
139 }
140 }
141
vhost_dummy_handle_output(VirtIODevice * vdev,VirtQueue * vq)142 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
143 {
144 }
145
vhost_scsi_pre_save(void * opaque)146 static int vhost_scsi_pre_save(void *opaque)
147 {
148 VHostSCSICommon *vsc = opaque;
149
150 /* At this point, backend must be stopped, otherwise
151 * it might keep writing to memory. */
152 assert(!vhost_dev_is_started(&vsc->dev));
153
154 return 0;
155 }
156
157 static const VMStateDescription vmstate_virtio_vhost_scsi = {
158 .name = "virtio-vhost_scsi",
159 .minimum_version_id = 1,
160 .version_id = 1,
161 .fields = (VMStateField[]) {
162 VMSTATE_VIRTIO_DEVICE,
163 VMSTATE_END_OF_LIST()
164 },
165 .pre_save = vhost_scsi_pre_save,
166 };
167
vhost_scsi_realize(DeviceState * dev,Error ** errp)168 static void vhost_scsi_realize(DeviceState *dev, Error **errp)
169 {
170 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
171 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev);
172 Error *err = NULL;
173 int vhostfd = -1;
174 int ret;
175 struct vhost_virtqueue *vqs = NULL;
176
177 if (!vs->conf.wwpn) {
178 error_setg(errp, "vhost-scsi: missing wwpn");
179 return;
180 }
181
182 if (vs->conf.vhostfd) {
183 vhostfd = monitor_fd_param(monitor_cur(), vs->conf.vhostfd, errp);
184 if (vhostfd == -1) {
185 error_prepend(errp, "vhost-scsi: unable to parse vhostfd: ");
186 return;
187 }
188 } else {
189 vhostfd = open("/dev/vhost-scsi", O_RDWR);
190 if (vhostfd < 0) {
191 error_setg(errp, "vhost-scsi: open vhost char device failed: %s",
192 strerror(errno));
193 return;
194 }
195 }
196
197 virtio_scsi_common_realize(dev,
198 vhost_dummy_handle_output,
199 vhost_dummy_handle_output,
200 vhost_dummy_handle_output,
201 &err);
202 if (err != NULL) {
203 error_propagate(errp, err);
204 goto close_fd;
205 }
206
207 if (!vsc->migratable) {
208 error_setg(&vsc->migration_blocker,
209 "vhost-scsi does not support migration in all cases. "
210 "When external environment supports it (Orchestrator migrates "
211 "target SCSI device state or use shared storage over network), "
212 "set 'migratable' property to true to enable migration.");
213 if (migrate_add_blocker_normal(&vsc->migration_blocker, errp) < 0) {
214 goto free_virtio;
215 }
216 }
217
218 vsc->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
219 vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs);
220 vsc->dev.vqs = vqs;
221 vsc->dev.vq_index = 0;
222 vsc->dev.backend_features = 0;
223
224 ret = vhost_dev_init(&vsc->dev, (void *)(uintptr_t)vhostfd,
225 VHOST_BACKEND_TYPE_KERNEL, 0, errp);
226 if (ret < 0) {
227 /*
228 * vhost_dev_init calls vhost_dev_cleanup on error, which closes
229 * vhostfd, don't double close it.
230 */
231 vhostfd = -1;
232 goto free_vqs;
233 }
234
235 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */
236 vsc->channel = 0;
237 vsc->lun = 0;
238 /* Note: we can also get the minimum tpgt from kernel */
239 vsc->target = vs->conf.boot_tpgt;
240
241 return;
242
243 free_vqs:
244 g_free(vqs);
245 if (!vsc->migratable) {
246 migrate_del_blocker(&vsc->migration_blocker);
247 }
248 free_virtio:
249 virtio_scsi_common_unrealize(dev);
250 close_fd:
251 if (vhostfd >= 0) {
252 close(vhostfd);
253 }
254 return;
255 }
256
vhost_scsi_unrealize(DeviceState * dev)257 static void vhost_scsi_unrealize(DeviceState *dev)
258 {
259 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
260 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev);
261 struct vhost_virtqueue *vqs = vsc->dev.vqs;
262
263 if (!vsc->migratable) {
264 migrate_del_blocker(&vsc->migration_blocker);
265 }
266
267 /* This will stop vhost backend. */
268 vhost_scsi_set_status(vdev, 0);
269
270 vhost_dev_cleanup(&vsc->dev);
271 g_free(vqs);
272
273 virtio_scsi_common_unrealize(dev);
274 }
275
vhost_scsi_get_vhost(VirtIODevice * vdev)276 static struct vhost_dev *vhost_scsi_get_vhost(VirtIODevice *vdev)
277 {
278 VHostSCSI *s = VHOST_SCSI(vdev);
279 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
280 return &vsc->dev;
281 }
282
283 static Property vhost_scsi_properties[] = {
284 DEFINE_PROP_STRING("vhostfd", VirtIOSCSICommon, conf.vhostfd),
285 DEFINE_PROP_STRING("wwpn", VirtIOSCSICommon, conf.wwpn),
286 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
287 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues,
288 VIRTIO_SCSI_AUTO_NUM_QUEUES),
289 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
290 128),
291 DEFINE_PROP_BOOL("seg_max_adjust", VirtIOSCSICommon, conf.seg_max_adjust,
292 true),
293 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
294 0xFFFF),
295 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
296 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features,
297 VIRTIO_SCSI_F_T10_PI,
298 false),
299 DEFINE_PROP_BOOL("migratable", VHostSCSICommon, migratable, false),
300 DEFINE_PROP_END_OF_LIST(),
301 };
302
vhost_scsi_class_init(ObjectClass * klass,void * data)303 static void vhost_scsi_class_init(ObjectClass *klass, void *data)
304 {
305 DeviceClass *dc = DEVICE_CLASS(klass);
306 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
307 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass);
308
309 device_class_set_props(dc, vhost_scsi_properties);
310 dc->vmsd = &vmstate_virtio_vhost_scsi;
311 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
312 vdc->realize = vhost_scsi_realize;
313 vdc->unrealize = vhost_scsi_unrealize;
314 vdc->get_features = vhost_scsi_common_get_features;
315 vdc->set_config = vhost_scsi_common_set_config;
316 vdc->set_status = vhost_scsi_set_status;
317 vdc->get_vhost = vhost_scsi_get_vhost;
318 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
319 }
320
vhost_scsi_instance_init(Object * obj)321 static void vhost_scsi_instance_init(Object *obj)
322 {
323 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj);
324
325 vsc->feature_bits = kernel_feature_bits;
326
327 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL,
328 DEVICE(vsc));
329 }
330
331 static const TypeInfo vhost_scsi_info = {
332 .name = TYPE_VHOST_SCSI,
333 .parent = TYPE_VHOST_SCSI_COMMON,
334 .instance_size = sizeof(VHostSCSI),
335 .class_init = vhost_scsi_class_init,
336 .instance_init = vhost_scsi_instance_init,
337 .interfaces = (InterfaceInfo[]) {
338 { TYPE_FW_PATH_PROVIDER },
339 { }
340 },
341 };
342
virtio_register_types(void)343 static void virtio_register_types(void)
344 {
345 type_register_static(&vhost_scsi_info);
346 }
347
348 type_init(virtio_register_types)
349