Re: [PATCH v5 2/3] uacce: add uacce driver

[zhangfei]

On 2019/10/16 äå1:55, reg Kroah-Hartman wrote:
> On Tue, Oct 15, 2019 at 03:39:00PM +0800, zhangfei wrote:
> > Hi, Jonathan
> >
> > On 2019/10/14 äå6:32, Jonathan Cameron wrote:
> > > On Mon, 14 Oct 2019 14:48:54 +0800
> > > Zhangfei Gao <zhangfei.gao@xxxxxxxxxx> wrote:
> > >
> > > > From: Kenneth Lee <liguozhu@xxxxxxxxxxxxx>
> > > >
> > > > Uacce (Unified/User-space-access-intended Accelerator Framework) targets to
> > > > provide Shared Virtual Addressing (SVA) between accelerators and processes.
> > > > So accelerator can access any data structure of the main cpu.
> > > > This differs from the data sharing between cpu and io device, which share
> > > > data content rather than address.
> > > > Since unified address, hardware and user space of process can share the
> > > > same virtual address in the communication.
> > > >
> > > > Uacce create a chrdev for every registration, the queue is allocated to
> > > > the process when the chrdev is opened. Then the process can access the
> > > > hardware resource by interact with the queue file. By mmap the queue
> > > > file space to user space, the process can directly put requests to the
> > > > hardware without syscall to the kernel space.
> > > >
> > > > Signed-off-by: Kenneth Lee <liguozhu@xxxxxxxxxxxxx>
> > > > Signed-off-by: Zaibo Xu <xuzaibo@xxxxxxxxxx>
> > > > Signed-off-by: Zhou Wang <wangzhou1@xxxxxxxxxxxxx>
> > > > Signed-off-by: Zhangfei Gao <zhangfei.gao@xxxxxxxxxx>
> > > Hi,
> > >
> > > Some superficial comments from me.
> > Thanks for the suggestion.
> > > > +/*
> > > > + * While user space releases a queue, all the relatives on the queue
> > > > + * should be released immediately by this putting.
> > > This one needs rewording but I'm not quite sure what
> > > relatives are in this case.
> > > > + */
> > > > +static long uacce_put_queue(struct uacce_queue *q)
> > > > +{
> > > > +	struct uacce_device *uacce = q->uacce;
> > > > +
> > > > +	mutex_lock(&uacce_mutex);
> > > > +
> > > > +	if ((q->state == UACCE_Q_STARTED) && uacce->ops->stop_queue)
> > > > +		uacce->ops->stop_queue(q);
> > > > +
> > > > +	if ((q->state == UACCE_Q_INIT || q->state == UACCE_Q_STARTED) &&
> > > > +	     uacce->ops->put_queue)
> > > > +		uacce->ops->put_queue(q);
> > > > +
> > > > +	q->state = UACCE_Q_ZOMBIE;
> > > > +	mutex_unlock(&uacce_mutex);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > ..
> > >
> > > > +
> > > > +static ssize_t qfrs_size_show(struct device *dev,
> > > > +				struct device_attribute *attr, char *buf)
> > > > +{
> > > > +	struct uacce_device *uacce = to_uacce_device(dev);
> > > > +	unsigned long size;
> > > > +	int i, ret;
> > > > +
> > > > +	for (i = 0, ret = 0; i < UACCE_QFRT_MAX; i++) {
> > > > +		size = uacce->qf_pg_size[i] << PAGE_SHIFT;
> > > > +		if (i == UACCE_QFRT_SS)
> > > > +			break;
> > > > +		ret += sprintf(buf + ret, "%lu\t", size);
> > > > +	}
> > > > +	ret += sprintf(buf + ret, "%lu\n", size);
> > > > +
> > > > +	return ret;
> > > > +}
> > > This may break the sysfs rule of one thing per file.  If you have
> > > multiple regions, they should probably each have their own file
> > > to give their size.
> > Is the rule must be applied?
> Yes, it always must be followed.  Please fix.
OK, understand. Have updated in v6.

Thanks for the patience.