Merge tag 'seabios-20211203-pull-request' of git://git.kraxel.org/qemu into staging
[qemu.git] / hw / 9pfs / virtio-9p-device.c
1 /*
2 * Virtio 9p backend
3 *
4 * Copyright IBM, Corp. 2010
5 *
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 *
12 */
13
14 #include "qemu/osdep.h"
15 #include "hw/virtio/virtio.h"
16 #include "qemu/sockets.h"
17 #include "virtio-9p.h"
18 #include "fsdev/qemu-fsdev.h"
19 #include "coth.h"
20 #include "hw/qdev-properties.h"
21 #include "hw/virtio/virtio-access.h"
22 #include "qemu/iov.h"
23 #include "qemu/module.h"
24 #include "sysemu/qtest.h"
25
26 static void virtio_9p_push_and_notify(V9fsPDU *pdu)
27 {
28 V9fsState *s = pdu->s;
29 V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
30 VirtQueueElement *elem = v->elems[pdu->idx];
31
32 /* push onto queue and notify */
33 virtqueue_push(v->vq, elem, pdu->size);
34 g_free(elem);
35 v->elems[pdu->idx] = NULL;
36
37 /* FIXME: we should batch these completions */
38 virtio_notify(VIRTIO_DEVICE(v), v->vq);
39 }
40
41 static void handle_9p_output(VirtIODevice *vdev, VirtQueue *vq)
42 {
43 V9fsVirtioState *v = (V9fsVirtioState *)vdev;
44 V9fsState *s = &v->state;
45 V9fsPDU *pdu;
46 ssize_t len;
47 VirtQueueElement *elem;
48
49 while ((pdu = pdu_alloc(s))) {
50 P9MsgHeader out;
51
52 elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
53 if (!elem) {
54 goto out_free_pdu;
55 }
56
57 if (iov_size(elem->in_sg, elem->in_num) < 7) {
58 virtio_error(vdev,
59 "The guest sent a VirtFS request without space for "
60 "the reply");
61 goto out_free_req;
62 }
63
64 len = iov_to_buf(elem->out_sg, elem->out_num, 0, &out, 7);
65 if (len != 7) {
66 virtio_error(vdev, "The guest sent a malformed VirtFS request: "
67 "header size is %zd, should be 7", len);
68 goto out_free_req;
69 }
70
71 v->elems[pdu->idx] = elem;
72
73 pdu_submit(pdu, &out);
74 }
75
76 return;
77
78 out_free_req:
79 virtqueue_detach_element(vq, elem, 0);
80 g_free(elem);
81 out_free_pdu:
82 pdu_free(pdu);
83 }
84
85 static uint64_t virtio_9p_get_features(VirtIODevice *vdev, uint64_t features,
86 Error **errp)
87 {
88 virtio_add_feature(&features, VIRTIO_9P_MOUNT_TAG);
89 return features;
90 }
91
92 static void virtio_9p_get_config(VirtIODevice *vdev, uint8_t *config)
93 {
94 int len;
95 struct virtio_9p_config *cfg;
96 V9fsVirtioState *v = VIRTIO_9P(vdev);
97 V9fsState *s = &v->state;
98
99 len = strlen(s->tag);
100 cfg = g_malloc0(sizeof(struct virtio_9p_config) + len);
101 virtio_stw_p(vdev, &cfg->tag_len, len);
102 /* We don't copy the terminating null to config space */
103 memcpy(cfg->tag, s->tag, len);
104 memcpy(config, cfg, v->config_size);
105 g_free(cfg);
106 }
107
108 static void virtio_9p_reset(VirtIODevice *vdev)
109 {
110 V9fsVirtioState *v = (V9fsVirtioState *)vdev;
111
112 v9fs_reset(&v->state);
113 }
114
115 static ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
116 const char *fmt, va_list ap)
117 {
118 V9fsState *s = pdu->s;
119 V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
120 VirtQueueElement *elem = v->elems[pdu->idx];
121 ssize_t ret;
122
123 ret = v9fs_iov_vmarshal(elem->in_sg, elem->in_num, offset, 1, fmt, ap);
124 if (ret < 0) {
125 VirtIODevice *vdev = VIRTIO_DEVICE(v);
126
127 virtio_error(vdev, "Failed to encode VirtFS reply type %d",
128 pdu->id + 1);
129 }
130 return ret;
131 }
132
133 static ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
134 const char *fmt, va_list ap)
135 {
136 V9fsState *s = pdu->s;
137 V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
138 VirtQueueElement *elem = v->elems[pdu->idx];
139 ssize_t ret;
140
141 ret = v9fs_iov_vunmarshal(elem->out_sg, elem->out_num, offset, 1, fmt, ap);
142 if (ret < 0) {
143 VirtIODevice *vdev = VIRTIO_DEVICE(v);
144
145 virtio_error(vdev, "Failed to decode VirtFS request type %d", pdu->id);
146 }
147 return ret;
148 }
149
150 static void virtio_init_in_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
151 unsigned int *pniov, size_t size)
152 {
153 V9fsState *s = pdu->s;
154 V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
155 VirtQueueElement *elem = v->elems[pdu->idx];
156 size_t buf_size = iov_size(elem->in_sg, elem->in_num);
157
158 if (buf_size < size) {
159 VirtIODevice *vdev = VIRTIO_DEVICE(v);
160
161 virtio_error(vdev,
162 "VirtFS reply type %d needs %zu bytes, buffer has %zu",
163 pdu->id + 1, size, buf_size);
164 }
165
166 *piov = elem->in_sg;
167 *pniov = elem->in_num;
168 }
169
170 static void virtio_init_out_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
171 unsigned int *pniov, size_t size)
172 {
173 V9fsState *s = pdu->s;
174 V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
175 VirtQueueElement *elem = v->elems[pdu->idx];
176 size_t buf_size = iov_size(elem->out_sg, elem->out_num);
177
178 if (buf_size < size) {
179 VirtIODevice *vdev = VIRTIO_DEVICE(v);
180
181 virtio_error(vdev,
182 "VirtFS request type %d needs %zu bytes, buffer has %zu",
183 pdu->id, size, buf_size);
184 }
185
186 *piov = elem->out_sg;
187 *pniov = elem->out_num;
188 }
189
190 static const V9fsTransport virtio_9p_transport = {
191 .pdu_vmarshal = virtio_pdu_vmarshal,
192 .pdu_vunmarshal = virtio_pdu_vunmarshal,
193 .init_in_iov_from_pdu = virtio_init_in_iov_from_pdu,
194 .init_out_iov_from_pdu = virtio_init_out_iov_from_pdu,
195 .push_and_notify = virtio_9p_push_and_notify,
196 };
197
198 static void virtio_9p_device_realize(DeviceState *dev, Error **errp)
199 {
200 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
201 V9fsVirtioState *v = VIRTIO_9P(dev);
202 V9fsState *s = &v->state;
203 FsDriverEntry *fse = get_fsdev_fsentry(s->fsconf.fsdev_id);
204
205 if (qtest_enabled() && fse) {
206 fse->export_flags |= V9FS_NO_PERF_WARN;
207 }
208
209 if (v9fs_device_realize_common(s, &virtio_9p_transport, errp)) {
210 return;
211 }
212
213 v->config_size = sizeof(struct virtio_9p_config) + strlen(s->fsconf.tag);
214 virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, v->config_size);
215 v->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output);
216 }
217
218 static void virtio_9p_device_unrealize(DeviceState *dev)
219 {
220 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
221 V9fsVirtioState *v = VIRTIO_9P(dev);
222 V9fsState *s = &v->state;
223
224 virtio_delete_queue(v->vq);
225 virtio_cleanup(vdev);
226 v9fs_device_unrealize_common(s);
227 }
228
229 /* virtio-9p device */
230
231 static const VMStateDescription vmstate_virtio_9p = {
232 .name = "virtio-9p",
233 .minimum_version_id = 1,
234 .version_id = 1,
235 .fields = (VMStateField[]) {
236 VMSTATE_VIRTIO_DEVICE,
237 VMSTATE_END_OF_LIST()
238 },
239 };
240
241 static Property virtio_9p_properties[] = {
242 DEFINE_PROP_STRING("mount_tag", V9fsVirtioState, state.fsconf.tag),
243 DEFINE_PROP_STRING("fsdev", V9fsVirtioState, state.fsconf.fsdev_id),
244 DEFINE_PROP_END_OF_LIST(),
245 };
246
247 static void virtio_9p_class_init(ObjectClass *klass, void *data)
248 {
249 DeviceClass *dc = DEVICE_CLASS(klass);
250 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
251
252 device_class_set_props(dc, virtio_9p_properties);
253 dc->vmsd = &vmstate_virtio_9p;
254 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
255 vdc->realize = virtio_9p_device_realize;
256 vdc->unrealize = virtio_9p_device_unrealize;
257 vdc->get_features = virtio_9p_get_features;
258 vdc->get_config = virtio_9p_get_config;
259 vdc->reset = virtio_9p_reset;
260 }
261
262 static const TypeInfo virtio_device_info = {
263 .name = TYPE_VIRTIO_9P,
264 .parent = TYPE_VIRTIO_DEVICE,
265 .instance_size = sizeof(V9fsVirtioState),
266 .class_init = virtio_9p_class_init,
267 };
268
269 static void virtio_9p_register_types(void)
270 {
271 type_register_static(&virtio_device_info);
272 }
273
274 type_init(virtio_9p_register_types)