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-rw-r--r--drivers/vhost/test.c376
1 files changed, 376 insertions, 0 deletions
diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c
new file mode 100644
index 000000000..bc8e7fb1e
--- /dev/null
+++ b/drivers/vhost/test.c
@@ -0,0 +1,376 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ *
+ * test virtio server in host kernel.
+ */
+
+#include <linux/compat.h>
+#include <linux/eventfd.h>
+#include <linux/vhost.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+
+#include "test.h"
+#include "vhost.h"
+
+/* Max number of bytes transferred before requeueing the job.
+ * Using this limit prevents one virtqueue from starving others. */
+#define VHOST_TEST_WEIGHT 0x80000
+
+/* Max number of packets transferred before requeueing the job.
+ * Using this limit prevents one virtqueue from starving others with
+ * pkts.
+ */
+#define VHOST_TEST_PKT_WEIGHT 256
+
+enum {
+ VHOST_TEST_VQ = 0,
+ VHOST_TEST_VQ_MAX = 1,
+};
+
+struct vhost_test {
+ struct vhost_dev dev;
+ struct vhost_virtqueue vqs[VHOST_TEST_VQ_MAX];
+};
+
+/* Expects to be always run from workqueue - which acts as
+ * read-size critical section for our kind of RCU. */
+static void handle_vq(struct vhost_test *n)
+{
+ struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ];
+ unsigned out, in;
+ int head;
+ size_t len, total_len = 0;
+ void *private;
+
+ mutex_lock(&vq->mutex);
+ private = vhost_vq_get_backend(vq);
+ if (!private) {
+ mutex_unlock(&vq->mutex);
+ return;
+ }
+
+ vhost_disable_notify(&n->dev, vq);
+
+ for (;;) {
+ head = vhost_get_vq_desc(vq, vq->iov,
+ ARRAY_SIZE(vq->iov),
+ &out, &in,
+ NULL, NULL);
+ /* On error, stop handling until the next kick. */
+ if (unlikely(head < 0))
+ break;
+ /* Nothing new? Wait for eventfd to tell us they refilled. */
+ if (head == vq->num) {
+ if (unlikely(vhost_enable_notify(&n->dev, vq))) {
+ vhost_disable_notify(&n->dev, vq);
+ continue;
+ }
+ break;
+ }
+ if (in) {
+ vq_err(vq, "Unexpected descriptor format for TX: "
+ "out %d, int %d\n", out, in);
+ break;
+ }
+ len = iov_length(vq->iov, out);
+ /* Sanity check */
+ if (!len) {
+ vq_err(vq, "Unexpected 0 len for TX\n");
+ break;
+ }
+ vhost_add_used_and_signal(&n->dev, vq, head, 0);
+ total_len += len;
+ if (unlikely(vhost_exceeds_weight(vq, 0, total_len)))
+ break;
+ }
+
+ mutex_unlock(&vq->mutex);
+}
+
+static void handle_vq_kick(struct vhost_work *work)
+{
+ struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
+ poll.work);
+ struct vhost_test *n = container_of(vq->dev, struct vhost_test, dev);
+
+ handle_vq(n);
+}
+
+static int vhost_test_open(struct inode *inode, struct file *f)
+{
+ struct vhost_test *n = kmalloc(sizeof *n, GFP_KERNEL);
+ struct vhost_dev *dev;
+ struct vhost_virtqueue **vqs;
+
+ if (!n)
+ return -ENOMEM;
+ vqs = kmalloc_array(VHOST_TEST_VQ_MAX, sizeof(*vqs), GFP_KERNEL);
+ if (!vqs) {
+ kfree(n);
+ return -ENOMEM;
+ }
+
+ dev = &n->dev;
+ vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ];
+ n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick;
+ vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX, UIO_MAXIOV,
+ VHOST_TEST_PKT_WEIGHT, VHOST_TEST_WEIGHT, true, NULL);
+
+ f->private_data = n;
+
+ return 0;
+}
+
+static void *vhost_test_stop_vq(struct vhost_test *n,
+ struct vhost_virtqueue *vq)
+{
+ void *private;
+
+ mutex_lock(&vq->mutex);
+ private = vhost_vq_get_backend(vq);
+ vhost_vq_set_backend(vq, NULL);
+ mutex_unlock(&vq->mutex);
+ return private;
+}
+
+static void vhost_test_stop(struct vhost_test *n, void **privatep)
+{
+ *privatep = vhost_test_stop_vq(n, n->vqs + VHOST_TEST_VQ);
+}
+
+static void vhost_test_flush(struct vhost_test *n)
+{
+ vhost_dev_flush(&n->dev);
+}
+
+static int vhost_test_release(struct inode *inode, struct file *f)
+{
+ struct vhost_test *n = f->private_data;
+ void *private;
+
+ vhost_test_stop(n, &private);
+ vhost_test_flush(n);
+ vhost_dev_stop(&n->dev);
+ vhost_dev_cleanup(&n->dev);
+ kfree(n->dev.vqs);
+ kfree(n);
+ return 0;
+}
+
+static long vhost_test_run(struct vhost_test *n, int test)
+{
+ void *priv, *oldpriv;
+ struct vhost_virtqueue *vq;
+ int r, index;
+
+ if (test < 0 || test > 1)
+ return -EINVAL;
+
+ mutex_lock(&n->dev.mutex);
+ r = vhost_dev_check_owner(&n->dev);
+ if (r)
+ goto err;
+
+ for (index = 0; index < n->dev.nvqs; ++index) {
+ /* Verify that ring has been setup correctly. */
+ if (!vhost_vq_access_ok(&n->vqs[index])) {
+ r = -EFAULT;
+ goto err;
+ }
+ }
+
+ for (index = 0; index < n->dev.nvqs; ++index) {
+ vq = n->vqs + index;
+ mutex_lock(&vq->mutex);
+ priv = test ? n : NULL;
+
+ /* start polling new socket */
+ oldpriv = vhost_vq_get_backend(vq);
+ vhost_vq_set_backend(vq, priv);
+
+ r = vhost_vq_init_access(&n->vqs[index]);
+
+ mutex_unlock(&vq->mutex);
+
+ if (r)
+ goto err;
+
+ if (oldpriv) {
+ vhost_test_flush(n);
+ }
+ }
+
+ mutex_unlock(&n->dev.mutex);
+ return 0;
+
+err:
+ mutex_unlock(&n->dev.mutex);
+ return r;
+}
+
+static long vhost_test_reset_owner(struct vhost_test *n)
+{
+ void *priv = NULL;
+ long err;
+ struct vhost_iotlb *umem;
+
+ mutex_lock(&n->dev.mutex);
+ err = vhost_dev_check_owner(&n->dev);
+ if (err)
+ goto done;
+ umem = vhost_dev_reset_owner_prepare();
+ if (!umem) {
+ err = -ENOMEM;
+ goto done;
+ }
+ vhost_test_stop(n, &priv);
+ vhost_test_flush(n);
+ vhost_dev_stop(&n->dev);
+ vhost_dev_reset_owner(&n->dev, umem);
+done:
+ mutex_unlock(&n->dev.mutex);
+ return err;
+}
+
+static int vhost_test_set_features(struct vhost_test *n, u64 features)
+{
+ struct vhost_virtqueue *vq;
+
+ mutex_lock(&n->dev.mutex);
+ if ((features & (1 << VHOST_F_LOG_ALL)) &&
+ !vhost_log_access_ok(&n->dev)) {
+ mutex_unlock(&n->dev.mutex);
+ return -EFAULT;
+ }
+ vq = &n->vqs[VHOST_TEST_VQ];
+ mutex_lock(&vq->mutex);
+ vq->acked_features = features;
+ mutex_unlock(&vq->mutex);
+ mutex_unlock(&n->dev.mutex);
+ return 0;
+}
+
+static long vhost_test_set_backend(struct vhost_test *n, unsigned index, int fd)
+{
+ static void *backend;
+
+ const bool enable = fd != -1;
+ struct vhost_virtqueue *vq;
+ int r;
+
+ mutex_lock(&n->dev.mutex);
+ r = vhost_dev_check_owner(&n->dev);
+ if (r)
+ goto err;
+
+ if (index >= VHOST_TEST_VQ_MAX) {
+ r = -ENOBUFS;
+ goto err;
+ }
+ vq = &n->vqs[index];
+ mutex_lock(&vq->mutex);
+
+ /* Verify that ring has been setup correctly. */
+ if (!vhost_vq_access_ok(vq)) {
+ r = -EFAULT;
+ goto err_vq;
+ }
+ if (!enable) {
+ vhost_poll_stop(&vq->poll);
+ backend = vhost_vq_get_backend(vq);
+ vhost_vq_set_backend(vq, NULL);
+ } else {
+ vhost_vq_set_backend(vq, backend);
+ r = vhost_vq_init_access(vq);
+ if (r == 0)
+ r = vhost_poll_start(&vq->poll, vq->kick);
+ }
+
+ mutex_unlock(&vq->mutex);
+
+ if (enable) {
+ vhost_test_flush(n);
+ }
+
+ mutex_unlock(&n->dev.mutex);
+ return 0;
+
+err_vq:
+ mutex_unlock(&vq->mutex);
+err:
+ mutex_unlock(&n->dev.mutex);
+ return r;
+}
+
+static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
+ unsigned long arg)
+{
+ struct vhost_vring_file backend;
+ struct vhost_test *n = f->private_data;
+ void __user *argp = (void __user *)arg;
+ u64 __user *featurep = argp;
+ int test;
+ u64 features;
+ int r;
+ switch (ioctl) {
+ case VHOST_TEST_RUN:
+ if (copy_from_user(&test, argp, sizeof test))
+ return -EFAULT;
+ return vhost_test_run(n, test);
+ case VHOST_TEST_SET_BACKEND:
+ if (copy_from_user(&backend, argp, sizeof backend))
+ return -EFAULT;
+ return vhost_test_set_backend(n, backend.index, backend.fd);
+ case VHOST_GET_FEATURES:
+ features = VHOST_FEATURES;
+ if (copy_to_user(featurep, &features, sizeof features))
+ return -EFAULT;
+ return 0;
+ case VHOST_SET_FEATURES:
+ printk(KERN_ERR "1\n");
+ if (copy_from_user(&features, featurep, sizeof features))
+ return -EFAULT;
+ printk(KERN_ERR "2\n");
+ if (features & ~VHOST_FEATURES)
+ return -EOPNOTSUPP;
+ printk(KERN_ERR "3\n");
+ return vhost_test_set_features(n, features);
+ case VHOST_RESET_OWNER:
+ return vhost_test_reset_owner(n);
+ default:
+ mutex_lock(&n->dev.mutex);
+ r = vhost_dev_ioctl(&n->dev, ioctl, argp);
+ if (r == -ENOIOCTLCMD)
+ r = vhost_vring_ioctl(&n->dev, ioctl, argp);
+ vhost_test_flush(n);
+ mutex_unlock(&n->dev.mutex);
+ return r;
+ }
+}
+
+static const struct file_operations vhost_test_fops = {
+ .owner = THIS_MODULE,
+ .release = vhost_test_release,
+ .unlocked_ioctl = vhost_test_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+ .open = vhost_test_open,
+ .llseek = noop_llseek,
+};
+
+static struct miscdevice vhost_test_misc = {
+ MISC_DYNAMIC_MINOR,
+ "vhost-test",
+ &vhost_test_fops,
+};
+module_misc_device(vhost_test_misc);
+
+MODULE_VERSION("0.0.1");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Michael S. Tsirkin");
+MODULE_DESCRIPTION("Host kernel side for virtio simulator");