vhost-scsi: prevent using uninitialized vqs
[qemu.git] / hw / scsi / vhost-scsi.c
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/queue.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/virtio/virtio-access.h"
30 #include "hw/fw-path-provider.h"
31 #include "qemu/cutils.h"
32
33 /* Features supported by host kernel. */
34 static const int kernel_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 VHOST_INVALID_FEATURE_BIT
40 };
41
42 static int vhost_scsi_set_endpoint(VHostSCSI *s)
43 {
44 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
45 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
46 const VhostOps *vhost_ops = vsc->dev.vhost_ops;
47 struct vhost_scsi_target backend;
48 int ret;
49
50 memset(&backend, 0, sizeof(backend));
51 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn);
52 ret = vhost_ops->vhost_scsi_set_endpoint(&vsc->dev, &backend);
53 if (ret < 0) {
54 return -errno;
55 }
56 return 0;
57 }
58
59 static void vhost_scsi_clear_endpoint(VHostSCSI *s)
60 {
61 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
62 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
63 struct vhost_scsi_target backend;
64 const VhostOps *vhost_ops = vsc->dev.vhost_ops;
65
66 memset(&backend, 0, sizeof(backend));
67 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn);
68 vhost_ops->vhost_scsi_clear_endpoint(&vsc->dev, &backend);
69 }
70
71 static int vhost_scsi_start(VHostSCSI *s)
72 {
73 int ret, abi_version;
74 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
75 const VhostOps *vhost_ops = vsc->dev.vhost_ops;
76
77 ret = vhost_ops->vhost_scsi_get_abi_version(&vsc->dev, &abi_version);
78 if (ret < 0) {
79 return -errno;
80 }
81 if (abi_version > VHOST_SCSI_ABI_VERSION) {
82 error_report("vhost-scsi: The running tcm_vhost kernel abi_version:"
83 " %d is greater than vhost_scsi userspace supports: %d,"
84 " please upgrade your version of QEMU", abi_version,
85 VHOST_SCSI_ABI_VERSION);
86 return -ENOSYS;
87 }
88
89 ret = vhost_scsi_common_start(vsc);
90 if (ret < 0) {
91 return ret;
92 }
93
94 ret = vhost_scsi_set_endpoint(s);
95 if (ret < 0) {
96 error_report("Error setting vhost-scsi endpoint");
97 vhost_scsi_common_stop(vsc);
98 }
99
100 return ret;
101 }
102
103 static void vhost_scsi_stop(VHostSCSI *s)
104 {
105 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
106
107 vhost_scsi_clear_endpoint(s);
108 vhost_scsi_common_stop(vsc);
109 }
110
111 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val)
112 {
113 VHostSCSI *s = VHOST_SCSI(vdev);
114 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
115 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK);
116
117 if (vsc->dev.started == start) {
118 return;
119 }
120
121 if (start) {
122 int ret;
123
124 ret = vhost_scsi_start(s);
125 if (ret < 0) {
126 error_report("unable to start vhost-scsi: %s", strerror(-ret));
127 exit(1);
128 }
129 } else {
130 vhost_scsi_stop(s);
131 }
132 }
133
134 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
135 {
136 }
137
138 static void vhost_scsi_realize(DeviceState *dev, Error **errp)
139 {
140 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
141 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev);
142 Error *err = NULL;
143 int vhostfd = -1;
144 int ret;
145
146 if (!vs->conf.wwpn) {
147 error_setg(errp, "vhost-scsi: missing wwpn");
148 return;
149 }
150
151 if (vs->conf.vhostfd) {
152 vhostfd = monitor_fd_param(cur_mon, vs->conf.vhostfd, errp);
153 if (vhostfd == -1) {
154 error_prepend(errp, "vhost-scsi: unable to parse vhostfd: ");
155 return;
156 }
157 } else {
158 vhostfd = open("/dev/vhost-scsi", O_RDWR);
159 if (vhostfd < 0) {
160 error_setg(errp, "vhost-scsi: open vhost char device failed: %s",
161 strerror(errno));
162 return;
163 }
164 }
165
166 virtio_scsi_common_realize(dev,
167 vhost_dummy_handle_output,
168 vhost_dummy_handle_output,
169 vhost_dummy_handle_output,
170 &err);
171 if (err != NULL) {
172 error_propagate(errp, err);
173 goto close_fd;
174 }
175
176 error_setg(&vsc->migration_blocker,
177 "vhost-scsi does not support migration");
178 migrate_add_blocker(vsc->migration_blocker, &err);
179 if (err) {
180 error_propagate(errp, err);
181 error_free(vsc->migration_blocker);
182 goto close_fd;
183 }
184
185 vsc->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
186 vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs);
187 vsc->dev.vq_index = 0;
188 vsc->dev.backend_features = 0;
189
190 ret = vhost_dev_init(&vsc->dev, (void *)(uintptr_t)vhostfd,
191 VHOST_BACKEND_TYPE_KERNEL, 0);
192 if (ret < 0) {
193 error_setg(errp, "vhost-scsi: vhost initialization failed: %s",
194 strerror(-ret));
195 goto free_vqs;
196 }
197
198 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */
199 vsc->channel = 0;
200 vsc->lun = 0;
201 /* Note: we can also get the minimum tpgt from kernel */
202 vsc->target = vs->conf.boot_tpgt;
203
204 return;
205
206 free_vqs:
207 migrate_del_blocker(vsc->migration_blocker);
208 g_free(vsc->dev.vqs);
209 close_fd:
210 close(vhostfd);
211 return;
212 }
213
214 static void vhost_scsi_unrealize(DeviceState *dev, Error **errp)
215 {
216 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
217 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev);
218
219 migrate_del_blocker(vsc->migration_blocker);
220 error_free(vsc->migration_blocker);
221
222 /* This will stop vhost backend. */
223 vhost_scsi_set_status(vdev, 0);
224
225 vhost_dev_cleanup(&vsc->dev);
226 g_free(vsc->dev.vqs);
227
228 virtio_scsi_common_unrealize(dev, errp);
229 }
230
231 static Property vhost_scsi_properties[] = {
232 DEFINE_PROP_STRING("vhostfd", VirtIOSCSICommon, conf.vhostfd),
233 DEFINE_PROP_STRING("wwpn", VirtIOSCSICommon, conf.wwpn),
234 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0),
235 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 1),
236 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size,
237 128),
238 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors,
239 0xFFFF),
240 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128),
241 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features,
242 VIRTIO_SCSI_F_T10_PI,
243 false),
244 DEFINE_PROP_END_OF_LIST(),
245 };
246
247 static void vhost_scsi_class_init(ObjectClass *klass, void *data)
248 {
249 DeviceClass *dc = DEVICE_CLASS(klass);
250 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
251 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass);
252
253 dc->props = vhost_scsi_properties;
254 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
255 vdc->realize = vhost_scsi_realize;
256 vdc->unrealize = vhost_scsi_unrealize;
257 vdc->get_features = vhost_scsi_common_get_features;
258 vdc->set_config = vhost_scsi_common_set_config;
259 vdc->set_status = vhost_scsi_set_status;
260 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path;
261 }
262
263 static void vhost_scsi_instance_init(Object *obj)
264 {
265 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj);
266
267 vsc->feature_bits = kernel_feature_bits;
268
269 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL,
270 DEVICE(vsc), NULL);
271 }
272
273 static const TypeInfo vhost_scsi_info = {
274 .name = TYPE_VHOST_SCSI,
275 .parent = TYPE_VHOST_SCSI_COMMON,
276 .instance_size = sizeof(VHostSCSI),
277 .class_init = vhost_scsi_class_init,
278 .instance_init = vhost_scsi_instance_init,
279 .interfaces = (InterfaceInfo[]) {
280 { TYPE_FW_PATH_PROVIDER },
281 { }
282 },
283 };
284
285 static void virtio_register_types(void)
286 {
287 type_register_static(&vhost_scsi_info);
288 }
289
290 type_init(virtio_register_types)