Re: [PATCH] mei, make modules.alias UUID information easier to read

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

Hi Prarit,

On Fri, Aug 28, 2015 at 07:50:52AM -0400, Prarit Bhargava wrote:
> Heikki, Tomas?

I'm afraid I don't know much about Intel's Management Engine
Interface. Looks like the driver is from Samuel (CC'd) so I'm guessing
he is the person you wanted comments from and not me.

cheers,

> On 08/14/2015 09:05 AM, Prarit Bhargava wrote:
> > 2nd try on this ...
> > 
> > P.
> > 
> > ---8<---
> > 
> > scripts/mod/file2alias.c:add_uuid() munges a UUID into a single string
> > which does not conform to the standard little endian UUID.  This patch
> > changes add_uuid() to use the UUID correctly so that future drivers which
> > use UUID matches can simply use the %pUL format, and modifies the mei
> > driver with those changes.
> > 
> > Cc: Tomas Winkler <tomas.winkler@intel.com>
> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > Cc: Joe Perches <joe@perches.com>
> > Cc: "David S. Miller" <davem@davemloft.net>
> > Cc: Jiri Kosina <jkosina@suse.cz>
> > Cc: Sharon Dvir <sharon.dvir1@mail.huji.ac.il>
> > Cc: "Suthikulpanit, Suravee" <Suravee.Suthikulpanit@amd.com>
> > Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> > Cc: James Hogan <james.hogan@imgtec.com>
> > Cc: Daniel Thompson <daniel.thompson@linaro.org>
> > Cc: Michael Opdenacker <michael.opdenacker@free-electrons.com>
> > Cc: David Cohen <david.a.cohen@linux.intel.com>
> > Cc: Felipe Balbi <balbi@ti.com>
> > Cc: Ralf Baechle <ralf@linux-mips.org>
> > 
> > Signed-off-by: Prarit Bhargava <prarit@redhat.com>
> > ---
> >  drivers/misc/mei/bus.c          |    6 ++----
> >  include/linux/mod_devicetable.h |    4 ----
> >  scripts/mod/file2alias.c        |    9 ++++++---
> >  3 files changed, 8 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
> > index 458aa5a..457e132 100644
> > --- a/drivers/misc/mei/bus.c
> > +++ b/drivers/misc/mei/bus.c
> > @@ -141,8 +141,7 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
> >  	const uuid_le *uuid = mei_me_cl_uuid(device->me_cl);
> >  	size_t len;
> >  
> > -	len = snprintf(buf, PAGE_SIZE, "mei:%s:" MEI_CL_UUID_FMT ":",
> > -		device->name, MEI_CL_UUID_ARGS(uuid->b));
> > +	len = snprintf(buf, PAGE_SIZE, "mei:%s:%pUl:", device->name, uuid);
> >  
> >  	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
> >  }
> > @@ -167,8 +166,7 @@ static int mei_cl_uevent(struct device *dev, struct kobj_uevent_env *env)
> >  	if (add_uevent_var(env, "MEI_CL_NAME=%s", device->name))
> >  		return -ENOMEM;
> >  
> > -	if (add_uevent_var(env, "MODALIAS=mei:%s:" MEI_CL_UUID_FMT ":",
> > -		device->name, MEI_CL_UUID_ARGS(uuid->b)))
> > +	if (add_uevent_var(env, "MODALIAS=mei:%s:%pUl:", device->name, uuid))
> >  		return -ENOMEM;
> >  
> >  	return 0;
> > diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
> > index 34f25b7..becda6f 100644
> > --- a/include/linux/mod_devicetable.h
> > +++ b/include/linux/mod_devicetable.h
> > @@ -601,10 +601,6 @@ struct ipack_device_id {
> >  
> >  #define MEI_CL_MODULE_PREFIX "mei:"
> >  #define MEI_CL_NAME_SIZE 32
> > -#define MEI_CL_UUID_FMT "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x"
> > -#define MEI_CL_UUID_ARGS(_u) \
> > -	_u[0], _u[1], _u[2], _u[3], _u[4], _u[5], _u[6], _u[7], \
> > -	_u[8], _u[9], _u[10], _u[11], _u[12], _u[13], _u[14], _u[15]
> >  
> >  /**
> >   * struct mei_cl_device_id - MEI client device identifier
> > diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
> > index 5f20882..8a46c60 100644
> > --- a/scripts/mod/file2alias.c
> > +++ b/scripts/mod/file2alias.c
> > @@ -137,10 +137,13 @@ static inline void add_wildcard(char *str)
> >  static inline void add_uuid(char *str, uuid_le uuid)
> >  {
> >  	int len = strlen(str);
> > -	int i;
> >  
> > -	for (i = 0; i < 16; i++)
> > -		sprintf(str + len + (i << 1), "%02x", uuid.b[i]);
> > +	sprintf(str + len,
> > +		"%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
> > +		uuid.b[3], uuid.b[2], uuid.b[1], uuid.b[0],
> > +		uuid.b[5], uuid.b[4], uuid.b[7], uuid.b[6],
> > +		uuid.b[8], uuid.b[9], uuid.b[10], uuid.b[11],
> > +		uuid.b[12], uuid.b[13], uuid.b[14], uuid.b[15]);
> >  }
> >  
> >  /**

-- 
heikki