1 /* Copyright (C) 2009 Red Hat, Inc.
2 * Author: Michael S. Tsirkin <mst@redhat.com>
4 * This work is licensed under the terms of the GNU GPL, version 2.
6 * test virtio server in host kernel.
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/rcupdate.h>
17 #include <linux/file.h>
18 #include <linux/slab.h>
23 /* Max number of bytes transferred before requeueing the job.
24 * Using this limit prevents one virtqueue from starving others. */
25 #define VHOST_TEST_WEIGHT 0x80000
29 VHOST_TEST_VQ_MAX = 1,
34 struct vhost_virtqueue vqs[VHOST_TEST_VQ_MAX];
37 /* Expects to be always run from workqueue - which acts as
38 * read-size critical section for our kind of RCU. */
39 static void handle_vq(struct vhost_test *n)
41 struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ];
44 size_t len, total_len = 0;
47 mutex_lock(&vq->mutex);
48 private = vq->private_data;
50 mutex_unlock(&vq->mutex);
54 vhost_disable_notify(&n->dev, vq);
57 head = vhost_get_vq_desc(&n->dev, vq, vq->iov,
61 /* On error, stop handling until the next kick. */
62 if (unlikely(head < 0))
64 /* Nothing new? Wait for eventfd to tell us they refilled. */
65 if (head == vq->num) {
66 if (unlikely(vhost_enable_notify(&n->dev, vq))) {
67 vhost_disable_notify(&n->dev, vq);
73 vq_err(vq, "Unexpected descriptor format for TX: "
74 "out %d, int %d\n", out, in);
77 len = iov_length(vq->iov, out);
80 vq_err(vq, "Unexpected 0 len for TX\n");
83 vhost_add_used_and_signal(&n->dev, vq, head, 0);
85 if (unlikely(total_len >= VHOST_TEST_WEIGHT)) {
86 vhost_poll_queue(&vq->poll);
91 mutex_unlock(&vq->mutex);
94 static void handle_vq_kick(struct vhost_work *work)
96 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
98 struct vhost_test *n = container_of(vq->dev, struct vhost_test, dev);
103 static int vhost_test_open(struct inode *inode, struct file *f)
105 struct vhost_test *n = kmalloc(sizeof *n, GFP_KERNEL);
106 struct vhost_dev *dev;
107 struct vhost_virtqueue **vqs;
112 vqs = kmalloc(VHOST_TEST_VQ_MAX * sizeof(*vqs), GFP_KERNEL);
119 vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ];
120 n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick;
121 r = vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX);
133 static void *vhost_test_stop_vq(struct vhost_test *n,
134 struct vhost_virtqueue *vq)
138 mutex_lock(&vq->mutex);
139 private = vq->private_data;
140 vq->private_data = NULL;
141 mutex_unlock(&vq->mutex);
145 static void vhost_test_stop(struct vhost_test *n, void **privatep)
147 *privatep = vhost_test_stop_vq(n, n->vqs + VHOST_TEST_VQ);
150 static void vhost_test_flush_vq(struct vhost_test *n, int index)
152 vhost_poll_flush(&n->vqs[index].poll);
155 static void vhost_test_flush(struct vhost_test *n)
157 vhost_test_flush_vq(n, VHOST_TEST_VQ);
160 static int vhost_test_release(struct inode *inode, struct file *f)
162 struct vhost_test *n = f->private_data;
165 vhost_test_stop(n, &private);
167 vhost_dev_cleanup(&n->dev, false);
168 /* We do an extra flush before freeing memory,
169 * since jobs can re-queue themselves. */
175 static long vhost_test_run(struct vhost_test *n, int test)
177 void *priv, *oldpriv;
178 struct vhost_virtqueue *vq;
181 if (test < 0 || test > 1)
184 mutex_lock(&n->dev.mutex);
185 r = vhost_dev_check_owner(&n->dev);
189 for (index = 0; index < n->dev.nvqs; ++index) {
190 /* Verify that ring has been setup correctly. */
191 if (!vhost_vq_access_ok(&n->vqs[index])) {
197 for (index = 0; index < n->dev.nvqs; ++index) {
199 mutex_lock(&vq->mutex);
200 priv = test ? n : NULL;
202 /* start polling new socket */
203 oldpriv = rcu_dereference_protected(vq->private_data,
204 lockdep_is_held(&vq->mutex));
205 rcu_assign_pointer(vq->private_data, priv);
207 r = vhost_init_used(&n->vqs[index]);
209 mutex_unlock(&vq->mutex);
215 vhost_test_flush_vq(n, index);
219 mutex_unlock(&n->dev.mutex);
223 mutex_unlock(&n->dev.mutex);
227 static long vhost_test_reset_owner(struct vhost_test *n)
231 struct vhost_memory *memory;
233 mutex_lock(&n->dev.mutex);
234 err = vhost_dev_check_owner(&n->dev);
237 memory = vhost_dev_reset_owner_prepare();
242 vhost_test_stop(n, &priv);
244 vhost_dev_reset_owner(&n->dev, memory);
246 mutex_unlock(&n->dev.mutex);
250 static int vhost_test_set_features(struct vhost_test *n, u64 features)
252 mutex_lock(&n->dev.mutex);
253 if ((features & (1 << VHOST_F_LOG_ALL)) &&
254 !vhost_log_access_ok(&n->dev)) {
255 mutex_unlock(&n->dev.mutex);
258 n->dev.acked_features = features;
261 mutex_unlock(&n->dev.mutex);
265 static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
268 struct vhost_test *n = f->private_data;
269 void __user *argp = (void __user *)arg;
270 u64 __user *featurep = argp;
276 if (copy_from_user(&test, argp, sizeof test))
278 return vhost_test_run(n, test);
279 case VHOST_GET_FEATURES:
280 features = VHOST_FEATURES;
281 if (copy_to_user(featurep, &features, sizeof features))
284 case VHOST_SET_FEATURES:
285 if (copy_from_user(&features, featurep, sizeof features))
287 if (features & ~VHOST_FEATURES)
289 return vhost_test_set_features(n, features);
290 case VHOST_RESET_OWNER:
291 return vhost_test_reset_owner(n);
293 mutex_lock(&n->dev.mutex);
294 r = vhost_dev_ioctl(&n->dev, ioctl, argp);
295 if (r == -ENOIOCTLCMD)
296 r = vhost_vring_ioctl(&n->dev, ioctl, argp);
298 mutex_unlock(&n->dev.mutex);
304 static long vhost_test_compat_ioctl(struct file *f, unsigned int ioctl,
307 return vhost_test_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
311 static const struct file_operations vhost_test_fops = {
312 .owner = THIS_MODULE,
313 .release = vhost_test_release,
314 .unlocked_ioctl = vhost_test_ioctl,
316 .compat_ioctl = vhost_test_compat_ioctl,
318 .open = vhost_test_open,
319 .llseek = noop_llseek,
322 static struct miscdevice vhost_test_misc = {
328 static int vhost_test_init(void)
330 return misc_register(&vhost_test_misc);
332 module_init(vhost_test_init);
334 static void vhost_test_exit(void)
336 misc_deregister(&vhost_test_misc);
338 module_exit(vhost_test_exit);
340 MODULE_VERSION("0.0.1");
341 MODULE_LICENSE("GPL v2");
342 MODULE_AUTHOR("Michael S. Tsirkin");
343 MODULE_DESCRIPTION("Host kernel side for virtio simulator");