[mirror_ubuntu-eoan-kernel.git] / drivers / vhost / test.c

// 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 = vq->private_data;
	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);

	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 = vq->private_data;
	vq->private_data = 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_vq(struct vhost_test *n, int index)
{
	vhost_poll_flush(&n->vqs[index].poll);
}

static void vhost_test_flush(struct vhost_test *n)
{
	vhost_test_flush_vq(n, VHOST_TEST_VQ);
}

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_cleanup(&n->dev);
	/* We do an extra flush before freeing memory,
	 * since jobs can re-queue themselves. */
	vhost_test_flush(n);
	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 = vq->private_data;
		vq->private_data = priv;

		r = vhost_vq_init_access(&n->vqs[index]);

		mutex_unlock(&vq->mutex);

		if (r)
			goto err;

		if (oldpriv) {
			vhost_test_flush_vq(n, index);
		}
	}

	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_umem *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_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_ioctl(struct file *f, unsigned int ioctl,
			     unsigned long arg)
{
	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_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;
	}
}

#ifdef CONFIG_COMPAT
static long vhost_test_compat_ioctl(struct file *f, unsigned int ioctl,
				   unsigned long arg)
{
	return vhost_test_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
}
#endif

static const struct file_operations vhost_test_fops = {
	.owner          = THIS_MODULE,
	.release        = vhost_test_release,
	.unlocked_ioctl = vhost_test_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl   = vhost_test_compat_ioctl,
#endif
	.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");
Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0-only
	2	/* Copyright (C) 2009 Red Hat, Inc.
	3	* Author: Michael S. Tsirkin <mst@redhat.com>
	4	*
	5	* test virtio server in host kernel.
	6	*/
	7
	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	/* Max number of bytes transferred before requeueing the job.
	22	* Using this limit prevents one virtqueue from starving others. */
	23	#define VHOST_TEST_WEIGHT 0x80000
	24
	25	/* Max number of packets transferred before requeueing the job.
	26	* Using this limit prevents one virtqueue from starving others with
	27	* pkts.
	28	*/
	29	#define VHOST_TEST_PKT_WEIGHT 256
	30
	31	enum {
	32	VHOST_TEST_VQ = 0,
	33	VHOST_TEST_VQ_MAX = 1,
	34	};
	35
	36	struct vhost_test {
	37	struct vhost_dev dev;
	38	struct vhost_virtqueue vqs[VHOST_TEST_VQ_MAX];
	39	};
	40
	41	/* Expects to be always run from workqueue - which acts as
	42	* read-size critical section for our kind of RCU. */
	43	static 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 = vq->private_data;
	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	/* On error, stop handling until the next kick. */
	66	if (unlikely(head < 0))
	67	break;
	68	/* Nothing new? Wait for eventfd to tell us they refilled. */
	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	/* Sanity check */
	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
	96	static 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
	105	static 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);
	124
	125	f->private_data = n;
	126
	127	return 0;
	128	}
	129
	130	static 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 = vq->private_data;
	137	vq->private_data = NULL;
	138	mutex_unlock(&vq->mutex);
	139	return private;
	140	}
	141
	142	static 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
	147	static void vhost_test_flush_vq(struct vhost_test *n, int index)
	148	{
	149	vhost_poll_flush(&n->vqs[index].poll);
	150	}
	151
	152	static void vhost_test_flush(struct vhost_test *n)
	153	{
	154	vhost_test_flush_vq(n, VHOST_TEST_VQ);
	155	}
	156
	157	static 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_cleanup(&n->dev);
	165	/* We do an extra flush before freeing memory,
	166	* since jobs can re-queue themselves. */
	167	vhost_test_flush(n);
	168	kfree(n);
	169	return 0;
	170	}
	171
	172	static long vhost_test_run(struct vhost_test *n, int test)
	173	{
	174	void priv, oldpriv;
	175	struct vhost_virtqueue *vq;
	176	int r, index;
	177
	178	if (test < 0 \|\| test > 1)
	179	return -EINVAL;
	180
	181	mutex_lock(&n->dev.mutex);
	182	r = vhost_dev_check_owner(&n->dev);
	183	if (r)
	184	goto err;
	185
	186	for (index = 0; index < n->dev.nvqs; ++index) {
	187	/* Verify that ring has been setup correctly. */
	188	if (!vhost_vq_access_ok(&n->vqs[index])) {
	189	r = -EFAULT;
	190	goto err;
	191	}
	192	}
	193
	194	for (index = 0; index < n->dev.nvqs; ++index) {
	195	vq = n->vqs + index;
	196	mutex_lock(&vq->mutex);
	197	priv = test ? n : NULL;
	198
	199	/* start polling new socket */
	200	oldpriv = vq->private_data;
	201	vq->private_data = priv;
	202
	203	r = vhost_vq_init_access(&n->vqs[index]);
	204
	205	mutex_unlock(&vq->mutex);
	206
	207	if (r)
	208	goto err;
	209
	210	if (oldpriv) {
	211	vhost_test_flush_vq(n, index);
	212	}
	213	}
	214
	215	mutex_unlock(&n->dev.mutex);
	216	return 0;
	217
	218	err:
	219	mutex_unlock(&n->dev.mutex);
	220	return r;
	221	}
	222
	223	static long vhost_test_reset_owner(struct vhost_test *n)
	224	{
	225	void *priv = NULL;
	226	long err;
	227	struct vhost_umem *umem;
	228
	229	mutex_lock(&n->dev.mutex);
	230	err = vhost_dev_check_owner(&n->dev);
	231	if (err)
	232	goto done;
	233	umem = vhost_dev_reset_owner_prepare();
	234	if (!umem) {
	235	err = -ENOMEM;
	236	goto done;
	237	}
	238	vhost_test_stop(n, &priv);
	239	vhost_test_flush(n);
	240	vhost_dev_reset_owner(&n->dev, umem);
	241	done:
	242	mutex_unlock(&n->dev.mutex);
	243	return err;
	244	}
	245
	246	static int vhost_test_set_features(struct vhost_test *n, u64 features)
	247	{
	248	struct vhost_virtqueue *vq;
	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	vq = &n->vqs[VHOST_TEST_VQ];
	257	mutex_lock(&vq->mutex);
	258	vq->acked_features = features;
	259	mutex_unlock(&vq->mutex);
	260	mutex_unlock(&n->dev.mutex);
	261	return 0;
	262	}
	263
	264	static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
	265	unsigned long arg)
	266	{
	267	struct vhost_test *n = f->private_data;
	268	void __user argp = (void __user )arg;
	269	u64 __user *featurep = argp;
	270	int test;
	271	u64 features;
	272	int r;
	273	switch (ioctl) {
	274	case VHOST_TEST_RUN:
	275	if (copy_from_user(&test, argp, sizeof test))
	276	return -EFAULT;
	277	return vhost_test_run(n, test);
	278	case VHOST_GET_FEATURES:
	279	features = VHOST_FEATURES;
	280	if (copy_to_user(featurep, &features, sizeof features))
	281	return -EFAULT;
	282	return 0;
	283	case VHOST_SET_FEATURES:
	284	printk(KERN_ERR "1\n");
	285	if (copy_from_user(&features, featurep, sizeof features))
	286	return -EFAULT;
	287	printk(KERN_ERR "2\n");
	288	if (features & ~VHOST_FEATURES)
	289	return -EOPNOTSUPP;
	290	printk(KERN_ERR "3\n");
	291	return vhost_test_set_features(n, features);
	292	case VHOST_RESET_OWNER:
	293	return vhost_test_reset_owner(n);
	294	default:
	295	mutex_lock(&n->dev.mutex);
	296	r = vhost_dev_ioctl(&n->dev, ioctl, argp);
	297	if (r == -ENOIOCTLCMD)
	298	r = vhost_vring_ioctl(&n->dev, ioctl, argp);
	299	vhost_test_flush(n);
	300	mutex_unlock(&n->dev.mutex);
	301	return r;
	302	}
	303	}
	304
	305	#ifdef CONFIG_COMPAT
	306	static long vhost_test_compat_ioctl(struct file *f, unsigned int ioctl,
	307	unsigned long arg)
	308	{
	309	return vhost_test_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
	310	}
	311	#endif
	312
	313	static const struct file_operations vhost_test_fops = {
	314	.owner = THIS_MODULE,
	315	.release = vhost_test_release,
	316	.unlocked_ioctl = vhost_test_ioctl,
	317	#ifdef CONFIG_COMPAT
	318	.compat_ioctl = vhost_test_compat_ioctl,
	319	#endif
	320	.open = vhost_test_open,
	321	.llseek = noop_llseek,
	322	};
	323
	324	static struct miscdevice vhost_test_misc = {
	325	MISC_DYNAMIC_MINOR,
	326	"vhost-test",
	327	&vhost_test_fops,
	328	};
	329	module_misc_device(vhost_test_misc);
	330
	331	MODULE_VERSION("0.0.1");
	332	MODULE_LICENSE("GPL v2");
	333	MODULE_AUTHOR("Michael S. Tsirkin");
	334	MODULE_DESCRIPTION("Host kernel side for virtio simulator");