Re: [PATCH] Fix /sys to /dev node name translation

[Karel Zak <kzak@redhat.com>]

On Tue, May 19, 2015 at 02:35:54PM +0200, Stanislav Brabec wrote:
> Karel Zak wrote:
> >On Mon, May 18, 2015 at 09:31:34PM +0200, Stanislav Brabec wrote:
> >>linux/drivers/base/core.c: device_get_devnode() defines a translation of
> >>'!' in sysfs nodes to '/' in /dev nodes. The same translation has to be
> >>done to properly support device nodes with slash (e. g. device nodes of
> >>cciss driver and several other drivers).
> >
> >Strange feature.
> 
> It was probably introduced to support drivers that already used /dev
> sub-directories in time of introduction /sys.
> 
> >>+	/* replace '!' in the name with '/', see
> >>+	 * linux/drivers/base/core.c: device_get_devnode() */
> >>+	while ((s = strchr(name, '!')))
> >>+		s[0] = '/';
> >
> >
> >  What about to add small inline function sysfs_fix_devname() to
> >  include/sysfs.h ?
> 
> Yes, it makes sense.
> 
> Do you have an idea how to locate all parts of code that make assumptions
> basename (sysfs_block_path) == basename (dev_path).

I hope we use lib/sysfs.c code always when possible. It should be
possible to detect all /sys code by 

    git grep _PATH_SYS_

so

    disk-utils/partx.c
    lib/loopdev.c
    lib/sysfs.c
    libblkid/src/devname.c
    misc-utils/lsblk.c

 the rest is irrelevant lscpu..

    Karel

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com