Merge tag 'edgar/xilinx-next-2022-09-21.for-upstream' of https://github.com/edgarigl...
[qemu.git] / hw / virtio / vhost-user-fs.c
1 /*
2 * Vhost-user filesystem virtio device
3 *
4 * Copyright 2018-2019 Red Hat, Inc.
5 *
6 * Authors:
7 * Stefan Hajnoczi <stefanha@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2 or
10 * (at your option) any later version. See the COPYING file in the
11 * top-level directory.
12 */
13
14 #include "qemu/osdep.h"
15 #include <sys/ioctl.h>
16 #include "standard-headers/linux/virtio_fs.h"
17 #include "qapi/error.h"
18 #include "hw/qdev-properties.h"
19 #include "hw/qdev-properties-system.h"
20 #include "hw/virtio/virtio-bus.h"
21 #include "hw/virtio/virtio-access.h"
22 #include "qemu/error-report.h"
23 #include "hw/virtio/vhost-user-fs.h"
24 #include "monitor/monitor.h"
25 #include "sysemu/sysemu.h"
26
27 static const int user_feature_bits[] = {
28 VIRTIO_F_VERSION_1,
29 VIRTIO_RING_F_INDIRECT_DESC,
30 VIRTIO_RING_F_EVENT_IDX,
31 VIRTIO_F_NOTIFY_ON_EMPTY,
32 VIRTIO_F_RING_PACKED,
33 VIRTIO_F_IOMMU_PLATFORM,
34
35 VHOST_INVALID_FEATURE_BIT
36 };
37
38 static void vuf_get_config(VirtIODevice *vdev, uint8_t *config)
39 {
40 VHostUserFS *fs = VHOST_USER_FS(vdev);
41 struct virtio_fs_config fscfg = {};
42
43 memcpy((char *)fscfg.tag, fs->conf.tag,
44 MIN(strlen(fs->conf.tag) + 1, sizeof(fscfg.tag)));
45
46 virtio_stl_p(vdev, &fscfg.num_request_queues, fs->conf.num_request_queues);
47
48 memcpy(config, &fscfg, sizeof(fscfg));
49 }
50
51 static void vuf_start(VirtIODevice *vdev)
52 {
53 VHostUserFS *fs = VHOST_USER_FS(vdev);
54 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
55 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
56 int ret;
57 int i;
58
59 if (!k->set_guest_notifiers) {
60 error_report("binding does not support guest notifiers");
61 return;
62 }
63
64 ret = vhost_dev_enable_notifiers(&fs->vhost_dev, vdev);
65 if (ret < 0) {
66 error_report("Error enabling host notifiers: %d", -ret);
67 return;
68 }
69
70 ret = k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, true);
71 if (ret < 0) {
72 error_report("Error binding guest notifier: %d", -ret);
73 goto err_host_notifiers;
74 }
75
76 fs->vhost_dev.acked_features = vdev->guest_features;
77 ret = vhost_dev_start(&fs->vhost_dev, vdev);
78 if (ret < 0) {
79 error_report("Error starting vhost: %d", -ret);
80 goto err_guest_notifiers;
81 }
82
83 /*
84 * guest_notifier_mask/pending not used yet, so just unmask
85 * everything here. virtio-pci will do the right thing by
86 * enabling/disabling irqfd.
87 */
88 for (i = 0; i < fs->vhost_dev.nvqs; i++) {
89 vhost_virtqueue_mask(&fs->vhost_dev, vdev, i, false);
90 }
91
92 return;
93
94 err_guest_notifiers:
95 k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, false);
96 err_host_notifiers:
97 vhost_dev_disable_notifiers(&fs->vhost_dev, vdev);
98 }
99
100 static void vuf_stop(VirtIODevice *vdev)
101 {
102 VHostUserFS *fs = VHOST_USER_FS(vdev);
103 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
104 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
105 int ret;
106
107 if (!k->set_guest_notifiers) {
108 return;
109 }
110
111 vhost_dev_stop(&fs->vhost_dev, vdev);
112
113 ret = k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, false);
114 if (ret < 0) {
115 error_report("vhost guest notifier cleanup failed: %d", ret);
116 return;
117 }
118
119 vhost_dev_disable_notifiers(&fs->vhost_dev, vdev);
120 }
121
122 static void vuf_set_status(VirtIODevice *vdev, uint8_t status)
123 {
124 VHostUserFS *fs = VHOST_USER_FS(vdev);
125 bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
126
127 if (!vdev->vm_running) {
128 should_start = false;
129 }
130
131 if (fs->vhost_dev.started == should_start) {
132 return;
133 }
134
135 if (should_start) {
136 vuf_start(vdev);
137 } else {
138 vuf_stop(vdev);
139 }
140 }
141
142 static uint64_t vuf_get_features(VirtIODevice *vdev,
143 uint64_t features,
144 Error **errp)
145 {
146 VHostUserFS *fs = VHOST_USER_FS(vdev);
147
148 return vhost_get_features(&fs->vhost_dev, user_feature_bits, features);
149 }
150
151 static void vuf_handle_output(VirtIODevice *vdev, VirtQueue *vq)
152 {
153 /*
154 * Not normally called; it's the daemon that handles the queue;
155 * however virtio's cleanup path can call this.
156 */
157 }
158
159 static void vuf_guest_notifier_mask(VirtIODevice *vdev, int idx,
160 bool mask)
161 {
162 VHostUserFS *fs = VHOST_USER_FS(vdev);
163
164 vhost_virtqueue_mask(&fs->vhost_dev, vdev, idx, mask);
165 }
166
167 static bool vuf_guest_notifier_pending(VirtIODevice *vdev, int idx)
168 {
169 VHostUserFS *fs = VHOST_USER_FS(vdev);
170
171 return vhost_virtqueue_pending(&fs->vhost_dev, idx);
172 }
173
174 static void vuf_device_realize(DeviceState *dev, Error **errp)
175 {
176 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
177 VHostUserFS *fs = VHOST_USER_FS(dev);
178 unsigned int i;
179 size_t len;
180 int ret;
181
182 if (!fs->conf.chardev.chr) {
183 error_setg(errp, "missing chardev");
184 return;
185 }
186
187 if (!fs->conf.tag) {
188 error_setg(errp, "missing tag property");
189 return;
190 }
191 len = strlen(fs->conf.tag);
192 if (len == 0) {
193 error_setg(errp, "tag property cannot be empty");
194 return;
195 }
196 if (len > sizeof_field(struct virtio_fs_config, tag)) {
197 error_setg(errp, "tag property must be %zu bytes or less",
198 sizeof_field(struct virtio_fs_config, tag));
199 return;
200 }
201
202 if (fs->conf.num_request_queues == 0) {
203 error_setg(errp, "num-request-queues property must be larger than 0");
204 return;
205 }
206
207 if (!is_power_of_2(fs->conf.queue_size)) {
208 error_setg(errp, "queue-size property must be a power of 2");
209 return;
210 }
211
212 if (fs->conf.queue_size > VIRTQUEUE_MAX_SIZE) {
213 error_setg(errp, "queue-size property must be %u or smaller",
214 VIRTQUEUE_MAX_SIZE);
215 return;
216 }
217
218 if (!vhost_user_init(&fs->vhost_user, &fs->conf.chardev, errp)) {
219 return;
220 }
221
222 virtio_init(vdev, "vhost-user-fs", VIRTIO_ID_FS,
223 sizeof(struct virtio_fs_config));
224
225 /* Hiprio queue */
226 fs->hiprio_vq = virtio_add_queue(vdev, fs->conf.queue_size, vuf_handle_output);
227
228 /* Request queues */
229 fs->req_vqs = g_new(VirtQueue *, fs->conf.num_request_queues);
230 for (i = 0; i < fs->conf.num_request_queues; i++) {
231 fs->req_vqs[i] = virtio_add_queue(vdev, fs->conf.queue_size, vuf_handle_output);
232 }
233
234 /* 1 high prio queue, plus the number configured */
235 fs->vhost_dev.nvqs = 1 + fs->conf.num_request_queues;
236 fs->vhost_dev.vqs = g_new0(struct vhost_virtqueue, fs->vhost_dev.nvqs);
237 ret = vhost_dev_init(&fs->vhost_dev, &fs->vhost_user,
238 VHOST_BACKEND_TYPE_USER, 0, errp);
239 if (ret < 0) {
240 goto err_virtio;
241 }
242
243 return;
244
245 err_virtio:
246 vhost_user_cleanup(&fs->vhost_user);
247 virtio_delete_queue(fs->hiprio_vq);
248 for (i = 0; i < fs->conf.num_request_queues; i++) {
249 virtio_delete_queue(fs->req_vqs[i]);
250 }
251 g_free(fs->req_vqs);
252 virtio_cleanup(vdev);
253 g_free(fs->vhost_dev.vqs);
254 return;
255 }
256
257 static void vuf_device_unrealize(DeviceState *dev)
258 {
259 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
260 VHostUserFS *fs = VHOST_USER_FS(dev);
261 int i;
262
263 /* This will stop vhost backend if appropriate. */
264 vuf_set_status(vdev, 0);
265
266 vhost_dev_cleanup(&fs->vhost_dev);
267
268 vhost_user_cleanup(&fs->vhost_user);
269
270 virtio_delete_queue(fs->hiprio_vq);
271 for (i = 0; i < fs->conf.num_request_queues; i++) {
272 virtio_delete_queue(fs->req_vqs[i]);
273 }
274 g_free(fs->req_vqs);
275 virtio_cleanup(vdev);
276 g_free(fs->vhost_dev.vqs);
277 fs->vhost_dev.vqs = NULL;
278 }
279
280 static const VMStateDescription vuf_vmstate = {
281 .name = "vhost-user-fs",
282 .unmigratable = 1,
283 };
284
285 static Property vuf_properties[] = {
286 DEFINE_PROP_CHR("chardev", VHostUserFS, conf.chardev),
287 DEFINE_PROP_STRING("tag", VHostUserFS, conf.tag),
288 DEFINE_PROP_UINT16("num-request-queues", VHostUserFS,
289 conf.num_request_queues, 1),
290 DEFINE_PROP_UINT16("queue-size", VHostUserFS, conf.queue_size, 128),
291 DEFINE_PROP_END_OF_LIST(),
292 };
293
294 static void vuf_instance_init(Object *obj)
295 {
296 VHostUserFS *fs = VHOST_USER_FS(obj);
297
298 device_add_bootindex_property(obj, &fs->bootindex, "bootindex",
299 "/filesystem@0", DEVICE(obj));
300 }
301
302 static void vuf_class_init(ObjectClass *klass, void *data)
303 {
304 DeviceClass *dc = DEVICE_CLASS(klass);
305 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
306
307 device_class_set_props(dc, vuf_properties);
308 dc->vmsd = &vuf_vmstate;
309 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
310 vdc->realize = vuf_device_realize;
311 vdc->unrealize = vuf_device_unrealize;
312 vdc->get_features = vuf_get_features;
313 vdc->get_config = vuf_get_config;
314 vdc->set_status = vuf_set_status;
315 vdc->guest_notifier_mask = vuf_guest_notifier_mask;
316 vdc->guest_notifier_pending = vuf_guest_notifier_pending;
317 }
318
319 static const TypeInfo vuf_info = {
320 .name = TYPE_VHOST_USER_FS,
321 .parent = TYPE_VIRTIO_DEVICE,
322 .instance_size = sizeof(VHostUserFS),
323 .instance_init = vuf_instance_init,
324 .class_init = vuf_class_init,
325 };
326
327 static void vuf_register_types(void)
328 {
329 type_register_static(&vuf_info);
330 }
331
332 type_init(vuf_register_types)