Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
[firefly-linux-kernel-4.4.55.git] / drivers / vhost / test.c
1 /* Copyright (C) 2009 Red Hat, Inc.
2  * Author: Michael S. Tsirkin <mst@redhat.com>
3  *
4  * This work is licensed under the terms of the GNU GPL, version 2.
5  *
6  * test virtio server in host kernel.
7  */
8
9 #include <linux/compat.h>
10 #include <linux/eventfd.h>
11 #include <linux/vhost.h>
12 #include <linux/miscdevice.h>
13 #include <linux/module.h>
14 #include <linux/mutex.h>
15 #include <linux/workqueue.h>
16 #include <linux/file.h>
17 #include <linux/slab.h>
18
19 #include "test.h"
20 #include "vhost.h"
21
22 /* Max number of bytes transferred before requeueing the job.
23  * Using this limit prevents one virtqueue from starving others. */
24 #define VHOST_TEST_WEIGHT 0x80000
25
26 enum {
27         VHOST_TEST_VQ = 0,
28         VHOST_TEST_VQ_MAX = 1,
29 };
30
31 struct vhost_test {
32         struct vhost_dev dev;
33         struct vhost_virtqueue vqs[VHOST_TEST_VQ_MAX];
34 };
35
36 /* Expects to be always run from workqueue - which acts as
37  * read-size critical section for our kind of RCU. */
38 static void handle_vq(struct vhost_test *n)
39 {
40         struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ];
41         unsigned out, in;
42         int head;
43         size_t len, total_len = 0;
44         void *private;
45
46         mutex_lock(&vq->mutex);
47         private = vq->private_data;
48         if (!private) {
49                 mutex_unlock(&vq->mutex);
50                 return;
51         }
52
53         vhost_disable_notify(&n->dev, vq);
54
55         for (;;) {
56                 head = vhost_get_vq_desc(&n->dev, vq, vq->iov,
57                                          ARRAY_SIZE(vq->iov),
58                                          &out, &in,
59                                          NULL, NULL);
60                 /* On error, stop handling until the next kick. */
61                 if (unlikely(head < 0))
62                         break;
63                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
64                 if (head == vq->num) {
65                         if (unlikely(vhost_enable_notify(&n->dev, vq))) {
66                                 vhost_disable_notify(&n->dev, vq);
67                                 continue;
68                         }
69                         break;
70                 }
71                 if (in) {
72                         vq_err(vq, "Unexpected descriptor format for TX: "
73                                "out %d, int %d\n", out, in);
74                         break;
75                 }
76                 len = iov_length(vq->iov, out);
77                 /* Sanity check */
78                 if (!len) {
79                         vq_err(vq, "Unexpected 0 len for TX\n");
80                         break;
81                 }
82                 vhost_add_used_and_signal(&n->dev, vq, head, 0);
83                 total_len += len;
84                 if (unlikely(total_len >= VHOST_TEST_WEIGHT)) {
85                         vhost_poll_queue(&vq->poll);
86                         break;
87                 }
88         }
89
90         mutex_unlock(&vq->mutex);
91 }
92
93 static void handle_vq_kick(struct vhost_work *work)
94 {
95         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
96                                                   poll.work);
97         struct vhost_test *n = container_of(vq->dev, struct vhost_test, dev);
98
99         handle_vq(n);
100 }
101
102 static int vhost_test_open(struct inode *inode, struct file *f)
103 {
104         struct vhost_test *n = kmalloc(sizeof *n, GFP_KERNEL);
105         struct vhost_dev *dev;
106         struct vhost_virtqueue **vqs;
107         int r;
108
109         if (!n)
110                 return -ENOMEM;
111         vqs = kmalloc(VHOST_TEST_VQ_MAX * sizeof(*vqs), GFP_KERNEL);
112         if (!vqs) {
113                 kfree(n);
114                 return -ENOMEM;
115         }
116
117         dev = &n->dev;
118         vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ];
119         n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick;
120         r = vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX);
121         if (r < 0) {
122                 kfree(vqs);
123                 kfree(n);
124                 return r;
125         }
126
127         f->private_data = n;
128
129         return 0;
130 }
131
132 static void *vhost_test_stop_vq(struct vhost_test *n,
133                                 struct vhost_virtqueue *vq)
134 {
135         void *private;
136
137         mutex_lock(&vq->mutex);
138         private = vq->private_data;
139         vq->private_data = NULL;
140         mutex_unlock(&vq->mutex);
141         return private;
142 }
143
144 static void vhost_test_stop(struct vhost_test *n, void **privatep)
145 {
146         *privatep = vhost_test_stop_vq(n, n->vqs + VHOST_TEST_VQ);
147 }
148
149 static void vhost_test_flush_vq(struct vhost_test *n, int index)
150 {
151         vhost_poll_flush(&n->vqs[index].poll);
152 }
153
154 static void vhost_test_flush(struct vhost_test *n)
155 {
156         vhost_test_flush_vq(n, VHOST_TEST_VQ);
157 }
158
159 static int vhost_test_release(struct inode *inode, struct file *f)
160 {
161         struct vhost_test *n = f->private_data;
162         void  *private;
163
164         vhost_test_stop(n, &private);
165         vhost_test_flush(n);
166         vhost_dev_cleanup(&n->dev, false);
167         /* We do an extra flush before freeing memory,
168          * since jobs can re-queue themselves. */
169         vhost_test_flush(n);
170         kfree(n);
171         return 0;
172 }
173
174 static 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                 /* Verify that ring has been setup correctly. */
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                 /* start polling new socket */
202                 oldpriv = vq->private_data;
203                 vq->private_data = priv;
204
205                 r = vhost_init_used(&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
220 err:
221         mutex_unlock(&n->dev.mutex);
222         return r;
223 }
224
225 static long vhost_test_reset_owner(struct vhost_test *n)
226 {
227         void *priv = NULL;
228         long err;
229         struct vhost_memory *memory;
230
231         mutex_lock(&n->dev.mutex);
232         err = vhost_dev_check_owner(&n->dev);
233         if (err)
234                 goto done;
235         memory = vhost_dev_reset_owner_prepare();
236         if (!memory) {
237                 err = -ENOMEM;
238                 goto done;
239         }
240         vhost_test_stop(n, &priv);
241         vhost_test_flush(n);
242         vhost_dev_reset_owner(&n->dev, memory);
243 done:
244         mutex_unlock(&n->dev.mutex);
245         return err;
246 }
247
248 static int vhost_test_set_features(struct vhost_test *n, u64 features)
249 {
250         mutex_lock(&n->dev.mutex);
251         if ((features & (1 << VHOST_F_LOG_ALL)) &&
252             !vhost_log_access_ok(&n->dev)) {
253                 mutex_unlock(&n->dev.mutex);
254                 return -EFAULT;
255         }
256         n->dev.acked_features = features;
257         smp_wmb();
258         vhost_test_flush(n);
259         mutex_unlock(&n->dev.mutex);
260         return 0;
261 }
262
263 static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
264                              unsigned long arg)
265 {
266         struct vhost_test *n = f->private_data;
267         void __user *argp = (void __user *)arg;
268         u64 __user *featurep = argp;
269         int test;
270         u64 features;
271         int r;
272         switch (ioctl) {
273         case VHOST_TEST_RUN:
274                 if (copy_from_user(&test, argp, sizeof test))
275                         return -EFAULT;
276                 return vhost_test_run(n, test);
277         case VHOST_GET_FEATURES:
278                 features = VHOST_FEATURES;
279                 if (copy_to_user(featurep, &features, sizeof features))
280                         return -EFAULT;
281                 return 0;
282         case VHOST_SET_FEATURES:
283                 if (copy_from_user(&features, featurep, sizeof features))
284                         return -EFAULT;
285                 if (features & ~VHOST_FEATURES)
286                         return -EOPNOTSUPP;
287                 return vhost_test_set_features(n, features);
288         case VHOST_RESET_OWNER:
289                 return vhost_test_reset_owner(n);
290         default:
291                 mutex_lock(&n->dev.mutex);
292                 r = vhost_dev_ioctl(&n->dev, ioctl, argp);
293                 if (r == -ENOIOCTLCMD)
294                         r = vhost_vring_ioctl(&n->dev, ioctl, argp);
295                 vhost_test_flush(n);
296                 mutex_unlock(&n->dev.mutex);
297                 return r;
298         }
299 }
300
301 #ifdef CONFIG_COMPAT
302 static long vhost_test_compat_ioctl(struct file *f, unsigned int ioctl,
303                                    unsigned long arg)
304 {
305         return vhost_test_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
306 }
307 #endif
308
309 static const struct file_operations vhost_test_fops = {
310         .owner          = THIS_MODULE,
311         .release        = vhost_test_release,
312         .unlocked_ioctl = vhost_test_ioctl,
313 #ifdef CONFIG_COMPAT
314         .compat_ioctl   = vhost_test_compat_ioctl,
315 #endif
316         .open           = vhost_test_open,
317         .llseek         = noop_llseek,
318 };
319
320 static struct miscdevice vhost_test_misc = {
321         MISC_DYNAMIC_MINOR,
322         "vhost-test",
323         &vhost_test_fops,
324 };
325
326 static int vhost_test_init(void)
327 {
328         return misc_register(&vhost_test_misc);
329 }
330 module_init(vhost_test_init);
331
332 static void vhost_test_exit(void)
333 {
334         misc_deregister(&vhost_test_misc);
335 }
336 module_exit(vhost_test_exit);
337
338 MODULE_VERSION("0.0.1");
339 MODULE_LICENSE("GPL v2");
340 MODULE_AUTHOR("Michael S. Tsirkin");
341 MODULE_DESCRIPTION("Host kernel side for virtio simulator");