On Tue, Oct 30, 2012 at 6:34 AM, Greg KH [off-list ref] wrote:

On Tue, Oct 30, 2012 at 06:25:50AM +0800, Zhi Yong Wu wrote:

quoted

On Tue, Oct 30, 2012 at 2:11 AM, Greg KH [off-list ref] wrote:

quoted

On Mon, Oct 29, 2012 at 12:30:55PM +0800, zwu.kernel@gmail.com wrote:

quoted

From: Zhi Yong Wu <redacted>

  The debugfs function is used to get expected dentry.

Huh?  Why do you need this?  Why haven't you added documentation for the

It is used to determine if one sysfs directory has been created. OK, i
will add some doc, thanks for your suggestion.

You didn't answer the "why" part here.  How come you think you need

ah, Let me say its scenario at first. If we do two mount ops as below:
1.) mount -o loop,hot_track image1 /data1
2.) mount -o loop,hot_track image2 /data2

The mount -o hot_track operation will automatically create one sysfs
directory /sys/kernel/debug/hot_track. To prevent this dir being
created again when 2.) is done, we need to know if it has existed at
first. In my patch, i at first get its dentry by this new function,
then determine if its d_inode field is NULL, if no, it means that this
sysfs dir has existed.
This is the reason that i want to add one new function.

this?  Can't you just save off the dentry you created somewhere so you
don't need to look it up again?

Because i can't find one appropriate place to save it.

greg k-h

-- 
Regards,

Zhi Yong Wu