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8#include <linux/compat.h>
9#include <linux/eventfd.h>
10#include <linux/vhost.h>
11#include <linux/miscdevice.h>
12#include <linux/module.h>
13#include <linux/mutex.h>
14#include <linux/workqueue.h>
15#include <linux/file.h>
16#include <linux/slab.h>
17
18#include "test.h"
19#include "vhost.h"
20
21
22
23#define VHOST_TEST_WEIGHT 0x80000
24
25
26
27
28
29#define VHOST_TEST_PKT_WEIGHT 256
30
31enum {
32 VHOST_TEST_VQ = 0,
33 VHOST_TEST_VQ_MAX = 1,
34};
35
36struct vhost_test {
37 struct vhost_dev dev;
38 struct vhost_virtqueue vqs[VHOST_TEST_VQ_MAX];
39};
40
41
42
43static void handle_vq(struct vhost_test *n)
44{
45 struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ];
46 unsigned out, in;
47 int head;
48 size_t len, total_len = 0;
49 void *private;
50
51 mutex_lock(&vq->mutex);
52 private = vhost_vq_get_backend(vq);
53 if (!private) {
54 mutex_unlock(&vq->mutex);
55 return;
56 }
57
58 vhost_disable_notify(&n->dev, vq);
59
60 for (;;) {
61 head = vhost_get_vq_desc(vq, vq->iov,
62 ARRAY_SIZE(vq->iov),
63 &out, &in,
64 NULL, NULL);
65
66 if (unlikely(head < 0))
67 break;
68
69 if (head == vq->num) {
70 if (unlikely(vhost_enable_notify(&n->dev, vq))) {
71 vhost_disable_notify(&n->dev, vq);
72 continue;
73 }
74 break;
75 }
76 if (in) {
77 vq_err(vq, "Unexpected descriptor format for TX: "
78 "out %d, int %d\n", out, in);
79 break;
80 }
81 len = iov_length(vq->iov, out);
82
83 if (!len) {
84 vq_err(vq, "Unexpected 0 len for TX\n");
85 break;
86 }
87 vhost_add_used_and_signal(&n->dev, vq, head, 0);
88 total_len += len;
89 if (unlikely(vhost_exceeds_weight(vq, 0, total_len)))
90 break;
91 }
92
93 mutex_unlock(&vq->mutex);
94}
95
96static void handle_vq_kick(struct vhost_work *work)
97{
98 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
99 poll.work);
100 struct vhost_test *n = container_of(vq->dev, struct vhost_test, dev);
101
102 handle_vq(n);
103}
104
105static int vhost_test_open(struct inode *inode, struct file *f)
106{
107 struct vhost_test *n = kmalloc(sizeof *n, GFP_KERNEL);
108 struct vhost_dev *dev;
109 struct vhost_virtqueue **vqs;
110
111 if (!n)
112 return -ENOMEM;
113 vqs = kmalloc_array(VHOST_TEST_VQ_MAX, sizeof(*vqs), GFP_KERNEL);
114 if (!vqs) {
115 kfree(n);
116 return -ENOMEM;
117 }
118
119 dev = &n->dev;
120 vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ];
121 n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick;
122 vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX, UIO_MAXIOV,
123 VHOST_TEST_PKT_WEIGHT, VHOST_TEST_WEIGHT, true, NULL);
124
125 f->private_data = n;
126
127 return 0;
128}
129
130static void *vhost_test_stop_vq(struct vhost_test *n,
131 struct vhost_virtqueue *vq)
132{
133 void *private;
134
135 mutex_lock(&vq->mutex);
136 private = vhost_vq_get_backend(vq);
137 vhost_vq_set_backend(vq, NULL);
138 mutex_unlock(&vq->mutex);
139 return private;
140}
141
142static void vhost_test_stop(struct vhost_test *n, void **privatep)
143{
144 *privatep = vhost_test_stop_vq(n, n->vqs + VHOST_TEST_VQ);
145}
146
147static void vhost_test_flush_vq(struct vhost_test *n, int index)
148{
149 vhost_poll_flush(&n->vqs[index].poll);
150}
151
152static void vhost_test_flush(struct vhost_test *n)
153{
154 vhost_test_flush_vq(n, VHOST_TEST_VQ);
155}
156
157static int vhost_test_release(struct inode *inode, struct file *f)
158{
159 struct vhost_test *n = f->private_data;
160 void *private;
161
162 vhost_test_stop(n, &private);
163 vhost_test_flush(n);
164 vhost_dev_stop(&n->dev);
165 vhost_dev_cleanup(&n->dev);
166
167
168 vhost_test_flush(n);
169 kfree(n->dev.vqs);
170 kfree(n);
171 return 0;
172}
173
174static long vhost_test_run(struct vhost_test *n, int test)
175{
176 void *priv, *oldpriv;
177 struct vhost_virtqueue *vq;
178 int r, index;
179
180 if (test < 0 || test > 1)
181 return -EINVAL;
182
183 mutex_lock(&n->dev.mutex);
184 r = vhost_dev_check_owner(&n->dev);
185 if (r)
186 goto err;
187
188 for (index = 0; index < n->dev.nvqs; ++index) {
189
190 if (!vhost_vq_access_ok(&n->vqs[index])) {
191 r = -EFAULT;
192 goto err;
193 }
194 }
195
196 for (index = 0; index < n->dev.nvqs; ++index) {
197 vq = n->vqs + index;
198 mutex_lock(&vq->mutex);
199 priv = test ? n : NULL;
200
201
202 oldpriv = vhost_vq_get_backend(vq);
203 vhost_vq_set_backend(vq, priv);
204
205 r = vhost_vq_init_access(&n->vqs[index]);
206
207 mutex_unlock(&vq->mutex);
208
209 if (r)
210 goto err;
211
212 if (oldpriv) {
213 vhost_test_flush_vq(n, index);
214 }
215 }
216
217 mutex_unlock(&n->dev.mutex);
218 return 0;
219
220err:
221 mutex_unlock(&n->dev.mutex);
222 return r;
223}
224
225static long vhost_test_reset_owner(struct vhost_test *n)
226{
227 void *priv = NULL;
228 long err;
229 struct vhost_iotlb *umem;
230
231 mutex_lock(&n->dev.mutex);
232 err = vhost_dev_check_owner(&n->dev);
233 if (err)
234 goto done;
235 umem = vhost_dev_reset_owner_prepare();
236 if (!umem) {
237 err = -ENOMEM;
238 goto done;
239 }
240 vhost_test_stop(n, &priv);
241 vhost_test_flush(n);
242 vhost_dev_stop(&n->dev);
243 vhost_dev_reset_owner(&n->dev, umem);
244done:
245 mutex_unlock(&n->dev.mutex);
246 return err;
247}
248
249static int vhost_test_set_features(struct vhost_test *n, u64 features)
250{
251 struct vhost_virtqueue *vq;
252
253 mutex_lock(&n->dev.mutex);
254 if ((features & (1 << VHOST_F_LOG_ALL)) &&
255 !vhost_log_access_ok(&n->dev)) {
256 mutex_unlock(&n->dev.mutex);
257 return -EFAULT;
258 }
259 vq = &n->vqs[VHOST_TEST_VQ];
260 mutex_lock(&vq->mutex);
261 vq->acked_features = features;
262 mutex_unlock(&vq->mutex);
263 mutex_unlock(&n->dev.mutex);
264 return 0;
265}
266
267static long vhost_test_set_backend(struct vhost_test *n, unsigned index, int fd)
268{
269 static void *backend;
270
271 const bool enable = fd != -1;
272 struct vhost_virtqueue *vq;
273 int r;
274
275 mutex_lock(&n->dev.mutex);
276 r = vhost_dev_check_owner(&n->dev);
277 if (r)
278 goto err;
279
280 if (index >= VHOST_TEST_VQ_MAX) {
281 r = -ENOBUFS;
282 goto err;
283 }
284 vq = &n->vqs[index];
285 mutex_lock(&vq->mutex);
286
287
288 if (!vhost_vq_access_ok(vq)) {
289 r = -EFAULT;
290 goto err_vq;
291 }
292 if (!enable) {
293 vhost_poll_stop(&vq->poll);
294 backend = vhost_vq_get_backend(vq);
295 vhost_vq_set_backend(vq, NULL);
296 } else {
297 vhost_vq_set_backend(vq, backend);
298 r = vhost_vq_init_access(vq);
299 if (r == 0)
300 r = vhost_poll_start(&vq->poll, vq->kick);
301 }
302
303 mutex_unlock(&vq->mutex);
304
305 if (enable) {
306 vhost_test_flush_vq(n, index);
307 }
308
309 mutex_unlock(&n->dev.mutex);
310 return 0;
311
312err_vq:
313 mutex_unlock(&vq->mutex);
314err:
315 mutex_unlock(&n->dev.mutex);
316 return r;
317}
318
319static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
320 unsigned long arg)
321{
322 struct vhost_vring_file backend;
323 struct vhost_test *n = f->private_data;
324 void __user *argp = (void __user *)arg;
325 u64 __user *featurep = argp;
326 int test;
327 u64 features;
328 int r;
329 switch (ioctl) {
330 case VHOST_TEST_RUN:
331 if (copy_from_user(&test, argp, sizeof test))
332 return -EFAULT;
333 return vhost_test_run(n, test);
334 case VHOST_TEST_SET_BACKEND:
335 if (copy_from_user(&backend, argp, sizeof backend))
336 return -EFAULT;
337 return vhost_test_set_backend(n, backend.index, backend.fd);
338 case VHOST_GET_FEATURES:
339 features = VHOST_FEATURES;
340 if (copy_to_user(featurep, &features, sizeof features))
341 return -EFAULT;
342 return 0;
343 case VHOST_SET_FEATURES:
344 printk(KERN_ERR "1\n");
345 if (copy_from_user(&features, featurep, sizeof features))
346 return -EFAULT;
347 printk(KERN_ERR "2\n");
348 if (features & ~VHOST_FEATURES)
349 return -EOPNOTSUPP;
350 printk(KERN_ERR "3\n");
351 return vhost_test_set_features(n, features);
352 case VHOST_RESET_OWNER:
353 return vhost_test_reset_owner(n);
354 default:
355 mutex_lock(&n->dev.mutex);
356 r = vhost_dev_ioctl(&n->dev, ioctl, argp);
357 if (r == -ENOIOCTLCMD)
358 r = vhost_vring_ioctl(&n->dev, ioctl, argp);
359 vhost_test_flush(n);
360 mutex_unlock(&n->dev.mutex);
361 return r;
362 }
363}
364
365static const struct file_operations vhost_test_fops = {
366 .owner = THIS_MODULE,
367 .release = vhost_test_release,
368 .unlocked_ioctl = vhost_test_ioctl,
369 .compat_ioctl = compat_ptr_ioctl,
370 .open = vhost_test_open,
371 .llseek = noop_llseek,
372};
373
374static struct miscdevice vhost_test_misc = {
375 MISC_DYNAMIC_MINOR,
376 "vhost-test",
377 &vhost_test_fops,
378};
379module_misc_device(vhost_test_misc);
380
381MODULE_VERSION("0.0.1");
382MODULE_LICENSE("GPL v2");
383MODULE_AUTHOR("Michael S. Tsirkin");
384MODULE_DESCRIPTION("Host kernel side for virtio simulator");
385
