Re: [PATCH] vhost-test: Make vhost/test.c work

[Asias He <asias@redhat.com>]

On Tue, May 07, 2013 at 02:22:32PM +0300, Michael S. Tsirkin wrote:
> On Tue, May 07, 2013 at 02:52:45PM +0800, Asias He wrote:
> > Fix it by:
> > 1) switching to use the new device specific fields per vq
> > 2) not including vhost.c, instead make vhost-test.ko depend on vhost.ko.
> 
> Please split this up.
> 1. make test work for 3.10
> 2. make test work for 3.11
> 
> thanks!

okay.

> > ---
> >  drivers/vhost/test.c | 37 +++++++++++++++++++++++++------------
> >  1 file changed, 25 insertions(+), 12 deletions(-)
> > 
> > diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c
> > index 1ee45bc..dc526eb 100644
> > --- a/drivers/vhost/test.c
> > +++ b/drivers/vhost/test.c
> > @@ -18,7 +18,7 @@
> >  #include <linux/slab.h>
> >  
> >  #include "test.h"
> > -#include "vhost.c"
> > +#include "vhost.h"
> >  
> >  /* Max number of bytes transferred before requeueing the job.
> >   * Using this limit prevents one virtqueue from starving others. */
> > @@ -29,16 +29,20 @@ enum {
> >  	VHOST_TEST_VQ_MAX = 1,
> >  };
> >  
> > +struct vhost_test_virtqueue {
> > +	struct vhost_virtqueue vq;
> > +};
> > +
> 
> This isn't needed or useful. Drop above change pls and patch
> size will shrink.

The difference is:

 drivers/vhost/test.c | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

 drivers/vhost/test.c | 35 ++++++++++++++++++++++++-----------
 1 file changed, 24 insertions(+), 11 deletions(-)

which is not significant.

So, I think it is better to code the same way as we do in vhost-net and
vhost-scsi which makes the device specific usage more consistent.

> >  struct vhost_test {
> >  	struct vhost_dev dev;
> > -	struct vhost_virtqueue vqs[VHOST_TEST_VQ_MAX];
> > +	struct vhost_test_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->dev.vqs[VHOST_TEST_VQ];
> > +	struct vhost_virtqueue *vq = n->dev.vqs[VHOST_TEST_VQ];
> >  	unsigned out, in;
> >  	int head;
> >  	size_t len, total_len = 0;
> > @@ -101,15 +105,23 @@ static void handle_vq_kick(struct vhost_work *work)
> >  static int vhost_test_open(struct inode *inode, struct file *f)
> >  {
> >  	struct vhost_test *n = kmalloc(sizeof *n, GFP_KERNEL);
> > +	struct vhost_virtqueue **vqs;
> >  	struct vhost_dev *dev;
> >  	int r;
> >  
> >  	if (!n)
> >  		return -ENOMEM;
> >  
> > +	vqs = kmalloc(VHOST_TEST_VQ_MAX * sizeof(*vqs), GFP_KERNEL);
> > +	if (!vqs) {
> > +		kfree(n);
> > +		return -ENOMEM;
> > +	}
> > +
> >  	dev = &n->dev;
> > -	n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick;
> > -	r = vhost_dev_init(dev, n->vqs, VHOST_TEST_VQ_MAX);
> > +	vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ].vq;
> > +	n->vqs[VHOST_TEST_VQ].vq.handle_kick = handle_vq_kick;
> > +	r = vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX);
> >  	if (r < 0) {
> >  		kfree(n);
> >  		return r;
> > @@ -135,12 +147,12 @@ static void *vhost_test_stop_vq(struct vhost_test *n,
> >  
> >  static void vhost_test_stop(struct vhost_test *n, void **privatep)
> >  {
> > -	*privatep = vhost_test_stop_vq(n, n->vqs + VHOST_TEST_VQ);
> > +	*privatep = vhost_test_stop_vq(n, &n->vqs[VHOST_TEST_VQ].vq);
> >  }
> >  
> >  static void vhost_test_flush_vq(struct vhost_test *n, int index)
> >  {
> > -	vhost_poll_flush(&n->dev.vqs[index].poll);
> > +	vhost_poll_flush(&n->vqs[index].vq.poll);
> >  }
> >  
> >  static void vhost_test_flush(struct vhost_test *n)
> > @@ -159,6 +171,7 @@ static int vhost_test_release(struct inode *inode, struct file *f)
> >  	/* We do an extra flush before freeing memory,
> >  	 * since jobs can re-queue themselves. */
> >  	vhost_test_flush(n);
> > +	kfree(n->dev.vqs);
> >  	kfree(n);
> >  	return 0;
> >  }
> > @@ -179,14 +192,14 @@ static long vhost_test_run(struct vhost_test *n, int test)
> >  
> >  	for (index = 0; index < n->dev.nvqs; ++index) {
> >  		/* Verify that ring has been setup correctly. */
> > -		if (!vhost_vq_access_ok(&n->vqs[index])) {
> > +		if (!vhost_vq_access_ok(&n->vqs[index].vq)) {
> >  			r = -EFAULT;
> >  			goto err;
> >  		}
> >  	}
> >  
> >  	for (index = 0; index < n->dev.nvqs; ++index) {
> > -		vq = n->vqs + index;
> > +		vq = &n->vqs[index].vq;
> >  		mutex_lock(&vq->mutex);
> >  		priv = test ? n : NULL;
> >  
> > @@ -195,7 +208,7 @@ static long vhost_test_run(struct vhost_test *n, int test)
> >  						    lockdep_is_held(&vq->mutex));
> >  		rcu_assign_pointer(vq->private_data, priv);
> >  
> > -		r = vhost_init_used(&n->vqs[index]);
> > +		r = vhost_init_used(&n->vqs[index].vq);
> >  
> >  		mutex_unlock(&vq->mutex);
> >  
> > @@ -268,14 +281,14 @@ static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
> >  			return -EFAULT;
> >  		return vhost_test_run(n, test);
> >  	case VHOST_GET_FEATURES:
> > -		features = VHOST_NET_FEATURES;
> > +		features = VHOST_FEATURES;
> >  		if (copy_to_user(featurep, &features, sizeof features))
> >  			return -EFAULT;
> >  		return 0;
> >  	case VHOST_SET_FEATURES:
> >  		if (copy_from_user(&features, featurep, sizeof features))
> >  			return -EFAULT;
> > -		if (features & ~VHOST_NET_FEATURES)
> > +		if (features & ~VHOST_FEATURES)
> >  			return -EOPNOTSUPP;
> >  		return vhost_test_set_features(n, features);
> >  	case VHOST_RESET_OWNER:
> > -- 
> > 1.8.1.4

-- 
Asias