[linux-2.6-block.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

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(total_len >= VHOST_TEST_WEIGHT)) {
			vhost_poll_queue(&vq->poll);
			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);

	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
7a338472	1	// SPDX-License-Identifier: GPL-2.0-only
71ccc212 MT	2	/* Copyright (C) 2009 Red Hat, Inc.
	3	* Author: Michael S. Tsirkin <mst@redhat.com>
	4	*
71ccc212 MT	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>
71ccc212 MT	15	#include <linux/file.h>
	16	#include <linux/slab.h>
	17
	18	#include "test.h"
6ac1afbf	19	#include "vhost.h"
71ccc212 MT	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	enum {
	26	VHOST_TEST_VQ = 0,
	27	VHOST_TEST_VQ_MAX = 1,
	28	};
	29
	30	struct vhost_test {
	31	struct vhost_dev dev;
	32	struct vhost_virtqueue vqs[VHOST_TEST_VQ_MAX];
	33	};
	34
	35	/* Expects to be always run from workqueue - which acts as
	36	* read-size critical section for our kind of RCU. */
	37	static void handle_vq(struct vhost_test *n)
	38	{
09a34c84	39	struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ];
71ccc212 MT	40	unsigned out, in;
	41	int head;
	42	size_t len, total_len = 0;
	43	void *private;
	44
09a34c84 MT	45	mutex_lock(&vq->mutex);
	46	private = vq->private_data;
	47	if (!private) {
	48	mutex_unlock(&vq->mutex);
71ccc212	49	return;
09a34c84	50	}
71ccc212	51
8ea8cf89	52	vhost_disable_notify(&n->dev, vq);
71ccc212 MT	53
71ccc212 MT	54	for (;;) {
47283bef	55	head = vhost_get_vq_desc(vq, vq->iov,
71ccc212 MT	56	ARRAY_SIZE(vq->iov),
	57	&out, &in,
	58	NULL, NULL);
	59	/* On error, stop handling until the next kick. */
	60	if (unlikely(head < 0))
	61	break;
	62	/* Nothing new? Wait for eventfd to tell us they refilled. */
	63	if (head == vq->num) {
8ea8cf89 MT	64	if (unlikely(vhost_enable_notify(&n->dev, vq))) {
8ea8cf89 MT	65	vhost_disable_notify(&n->dev, vq);
71ccc212 MT	66	continue;
	67	}
	68	break;
	69	}
	70	if (in) {
	71	vq_err(vq, "Unexpected descriptor format for TX: "
	72	"out %d, int %d\n", out, in);
	73	break;
	74	}
	75	len = iov_length(vq->iov, out);
	76	/* Sanity check */
	77	if (!len) {
	78	vq_err(vq, "Unexpected 0 len for TX\n");
	79	break;
	80	}
	81	vhost_add_used_and_signal(&n->dev, vq, head, 0);
	82	total_len += len;
	83	if (unlikely(total_len >= VHOST_TEST_WEIGHT)) {
	84	vhost_poll_queue(&vq->poll);
	85	break;
	86	}
	87	}
	88
	89	mutex_unlock(&vq->mutex);
	90	}
	91
	92	static void handle_vq_kick(struct vhost_work *work)
	93	{
	94	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
	95	poll.work);
	96	struct vhost_test *n = container_of(vq->dev, struct vhost_test, dev);
	97
	98	handle_vq(n);
	99	}
	100
	101	static int vhost_test_open(struct inode inode, struct file f)
	102	{
	103	struct vhost_test n = kmalloc(sizeof n, GFP_KERNEL);
	104	struct vhost_dev *dev;
09a34c84	105	struct vhost_virtqueue **vqs;
71ccc212 MT	106
	107	if (!n)
	108	return -ENOMEM;
6da2ec56	109	vqs = kmalloc_array(VHOST_TEST_VQ_MAX, sizeof(*vqs), GFP_KERNEL);
09a34c84 MT	110	if (!vqs) {
	111	kfree(n);
	112	return -ENOMEM;
	113	}
71ccc212 MT	114
71ccc212 MT	115	dev = &n->dev;
09a34c84	116	vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ];
71ccc212	117	n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick;
93d2c4de	118	vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX, UIO_MAXIOV);
71ccc212 MT	119
	120	f->private_data = n;
	121
	122	return 0;
	123	}
	124
	125	static void vhost_test_stop_vq(struct vhost_test n,
	126	struct vhost_virtqueue *vq)
	127	{
	128	void *private;
	129
	130	mutex_lock(&vq->mutex);
09a34c84 MT	131	private = vq->private_data;
09a34c84 MT	132	vq->private_data = NULL;
71ccc212 MT	133	mutex_unlock(&vq->mutex);
	134	return private;
	135	}
	136
	137	static void vhost_test_stop(struct vhost_test n, void *privatep)
	138	{
	139	*privatep = vhost_test_stop_vq(n, n->vqs + VHOST_TEST_VQ);
	140	}
	141
	142	static void vhost_test_flush_vq(struct vhost_test *n, int index)
	143	{
09a34c84	144	vhost_poll_flush(&n->vqs[index].poll);
71ccc212 MT	145	}
	146
	147	static void vhost_test_flush(struct vhost_test *n)
	148	{
	149	vhost_test_flush_vq(n, VHOST_TEST_VQ);
	150	}
	151
	152	static int vhost_test_release(struct inode inode, struct file f)
	153	{
	154	struct vhost_test *n = f->private_data;
	155	void *private;
	156
	157	vhost_test_stop(n, &private);
	158	vhost_test_flush(n);
f6f93f75	159	vhost_dev_cleanup(&n->dev);
71ccc212 MT	160	/* We do an extra flush before freeing memory,
	161	* since jobs can re-queue themselves. */
	162	vhost_test_flush(n);
	163	kfree(n);
	164	return 0;
	165	}
	166
	167	static long vhost_test_run(struct vhost_test *n, int test)
	168	{
	169	void priv, oldpriv;
	170	struct vhost_virtqueue *vq;
	171	int r, index;
	172
	173	if (test < 0 \|\| test > 1)
	174	return -EINVAL;
	175
	176	mutex_lock(&n->dev.mutex);
	177	r = vhost_dev_check_owner(&n->dev);
	178	if (r)
	179	goto err;
	180
	181	for (index = 0; index < n->dev.nvqs; ++index) {
	182	/* Verify that ring has been setup correctly. */
	183	if (!vhost_vq_access_ok(&n->vqs[index])) {
	184	r = -EFAULT;
	185	goto err;
	186	}
	187	}
	188
	189	for (index = 0; index < n->dev.nvqs; ++index) {
	190	vq = n->vqs + index;
	191	mutex_lock(&vq->mutex);
	192	priv = test ? n : NULL;
	193
	194	/* start polling new socket */
22fa90c7 AH	195	oldpriv = vq->private_data;
22fa90c7 AH	196	vq->private_data = priv;
71ccc212	197
80f7d030	198	r = vhost_vq_init_access(&n->vqs[index]);
f59281da	199
71ccc212 MT	200	mutex_unlock(&vq->mutex);
71ccc212 MT	201
f59281da JW	202	if (r)
	203	goto err;
	204
71ccc212 MT	205	if (oldpriv) {
	206	vhost_test_flush_vq(n, index);
	207	}
	208	}
	209
	210	mutex_unlock(&n->dev.mutex);
	211	return 0;
	212
	213	err:
	214	mutex_unlock(&n->dev.mutex);
	215	return r;
	216	}
	217
	218	static long vhost_test_reset_owner(struct vhost_test *n)
	219	{
	220	void *priv = NULL;
	221	long err;
446374d7	222	struct vhost_umem *umem;
150b9e51	223
71ccc212 MT	224	mutex_lock(&n->dev.mutex);
	225	err = vhost_dev_check_owner(&n->dev);
	226	if (err)
	227	goto done;
446374d7 MT	228	umem = vhost_dev_reset_owner_prepare();
446374d7 MT	229	if (!umem) {
150b9e51 MT	230	err = -ENOMEM;
	231	goto done;
	232	}
71ccc212 MT	233	vhost_test_stop(n, &priv);
71ccc212 MT	234	vhost_test_flush(n);
446374d7	235	vhost_dev_reset_owner(&n->dev, umem);
71ccc212 MT	236	done:
	237	mutex_unlock(&n->dev.mutex);
	238	return err;
	239	}
	240
	241	static int vhost_test_set_features(struct vhost_test *n, u64 features)
	242	{
ea16c514 MT	243	struct vhost_virtqueue *vq;
ea16c514 MT	244
71ccc212 MT	245	mutex_lock(&n->dev.mutex);
	246	if ((features & (1 << VHOST_F_LOG_ALL)) &&
	247	!vhost_log_access_ok(&n->dev)) {
	248	mutex_unlock(&n->dev.mutex);
	249	return -EFAULT;
	250	}
ea16c514 MT	251	vq = &n->vqs[VHOST_TEST_VQ];
	252	mutex_lock(&vq->mutex);
	253	vq->acked_features = features;
	254	mutex_unlock(&vq->mutex);
71ccc212 MT	255	mutex_unlock(&n->dev.mutex);
	256	return 0;
	257	}
	258
	259	static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
	260	unsigned long arg)
	261	{
	262	struct vhost_test *n = f->private_data;
	263	void __user argp = (void __user )arg;
	264	u64 __user *featurep = argp;
	265	int test;
	266	u64 features;
	267	int r;
	268	switch (ioctl) {
	269	case VHOST_TEST_RUN:
	270	if (copy_from_user(&test, argp, sizeof test))
	271	return -EFAULT;
	272	return vhost_test_run(n, test);
	273	case VHOST_GET_FEATURES:
09a34c84	274	features = VHOST_FEATURES;
71ccc212 MT	275	if (copy_to_user(featurep, &features, sizeof features))
	276	return -EFAULT;
	277	return 0;
	278	case VHOST_SET_FEATURES:
4e9fa50c	279	printk(KERN_ERR "1\n");
71ccc212 MT	280	if (copy_from_user(&features, featurep, sizeof features))
71ccc212 MT	281	return -EFAULT;
4e9fa50c	282	printk(KERN_ERR "2\n");
09a34c84	283	if (features & ~VHOST_FEATURES)
71ccc212	284	return -EOPNOTSUPP;
4e9fa50c	285	printk(KERN_ERR "3\n");
71ccc212 MT	286	return vhost_test_set_features(n, features);
	287	case VHOST_RESET_OWNER:
	288	return vhost_test_reset_owner(n);
	289	default:
	290	mutex_lock(&n->dev.mutex);
73640c99 MT	291	r = vhost_dev_ioctl(&n->dev, ioctl, argp);
	292	if (r == -ENOIOCTLCMD)
	293	r = vhost_vring_ioctl(&n->dev, ioctl, argp);
71ccc212 MT	294	vhost_test_flush(n);
	295	mutex_unlock(&n->dev.mutex);
	296	return r;
	297	}
	298	}
	299
	300	#ifdef CONFIG_COMPAT
	301	static long vhost_test_compat_ioctl(struct file *f, unsigned int ioctl,
	302	unsigned long arg)
	303	{
	304	return vhost_test_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
	305	}
	306	#endif
	307
	308	static const struct file_operations vhost_test_fops = {
	309	.owner = THIS_MODULE,
	310	.release = vhost_test_release,
	311	.unlocked_ioctl = vhost_test_ioctl,
	312	#ifdef CONFIG_COMPAT
	313	.compat_ioctl = vhost_test_compat_ioctl,
	314	#endif
	315	.open = vhost_test_open,
	316	.llseek = noop_llseek,
	317	};
	318
	319	static struct miscdevice vhost_test_misc = {
	320	MISC_DYNAMIC_MINOR,
	321	"vhost-test",
	322	&vhost_test_fops,
	323	};
ca75d601	324	module_misc_device(vhost_test_misc);
71ccc212 MT	325
	326	MODULE_VERSION("0.0.1");
	327	MODULE_LICENSE("GPL v2");
	328	MODULE_AUTHOR("Michael S. Tsirkin");
	329	MODULE_DESCRIPTION("Host kernel side for virtio simulator");