Re: [PATCH v5 2/9] moduleparam: add data member to struct kernel_param

2021-08-13 Thread jim . cromie
On Fri, Aug 13, 2021 at 9:44 AM Andy Shevchenko
 wrote:
>
> On Fri, Aug 13, 2021 at 09:17:10AM -0600, Jim Cromie wrote:
> > Add a const void* data member to the struct, to allow attaching
> > private data that will be used soon by a setter method (via kp->data)
> > to perform more elaborate actions.
> >
> > To attach the data at compile time, add new macros:
> >
> > module_param_cbd() derives from module_param_cb(), adding data param,
> > and latter is redefined to use former.
> >
> > It calls __module_param_call_wdata(), which accepts a new data param
> > and inits .data with it. Re-define __module_param_call() to use it.
> >
> > Use of this new data member will be rare, it might be worth redoing
> > this as a separate/sub-type to de-bloat the base case.
>
> ...
>
> > +#define module_param_cbd(name, ops, arg, perm, data)   
> >   \
> > + __module_param_call_wdata(MODULE_PARAM_PREFIX, name, ops, arg, perm, 
> > -1, 0, data)
>
> Cryptic name. Moreover, inconsistent with the rest.
> What about module_param_cb_data() ?
>
> >  #define module_param_cb_unsafe(name, ops, arg, perm)   
> > \
> >   __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1,
> > \
> >   KERNEL_PARAM_FL_UNSAFE)
>
> (above left for the above comment)
>
> ...
>
> > +#define __module_param_call_wdata(prefix, name, ops, arg, perm, level, 
> > flags, data) \
>
> Similar __module_param_call_with_data()
>
> --
> With Best Regards,
> Andy Shevchenko
>
>

yes to all renames, revised.
thanks


Re: [PATCH v5 2/9] moduleparam: add data member to struct kernel_param

2021-08-13 Thread Andy Shevchenko
On Fri, Aug 13, 2021 at 09:17:10AM -0600, Jim Cromie wrote:
> Add a const void* data member to the struct, to allow attaching
> private data that will be used soon by a setter method (via kp->data)
> to perform more elaborate actions.
> 
> To attach the data at compile time, add new macros:
> 
> module_param_cbd() derives from module_param_cb(), adding data param,
> and latter is redefined to use former.
> 
> It calls __module_param_call_wdata(), which accepts a new data param
> and inits .data with it. Re-define __module_param_call() to use it.
> 
> Use of this new data member will be rare, it might be worth redoing
> this as a separate/sub-type to de-bloat the base case.

...

> +#define module_param_cbd(name, ops, arg, perm, data) 
> \
> + __module_param_call_wdata(MODULE_PARAM_PREFIX, name, ops, arg, perm, 
> -1, 0, data)

Cryptic name. Moreover, inconsistent with the rest.
What about module_param_cb_data() ?

>  #define module_param_cb_unsafe(name, ops, arg, perm)   \
>   __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1,\
>   KERNEL_PARAM_FL_UNSAFE)

(above left for the above comment)

...

> +#define __module_param_call_wdata(prefix, name, ops, arg, perm, level, 
> flags, data) \

Similar __module_param_call_with_data()

-- 
With Best Regards,
Andy Shevchenko




[PATCH v5 2/9] moduleparam: add data member to struct kernel_param

2021-08-13 Thread Jim Cromie
Add a const void* data member to the struct, to allow attaching
private data that will be used soon by a setter method (via kp->data)
to perform more elaborate actions.

To attach the data at compile time, add new macros:

module_param_cbd() derives from module_param_cb(), adding data param,
and latter is redefined to use former.

It calls __module_param_call_wdata(), which accepts a new data param
and inits .data with it. Re-define __module_param_call() to use it.

Use of this new data member will be rare, it might be worth redoing
this as a separate/sub-type to de-bloat the base case.

---
v4+:
. const void* data - 

Signed-off-by: Jim Cromie 
---
 include/linux/moduleparam.h | 11 +--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h
index eed280fae433..878387e0b2d9 100644
--- a/include/linux/moduleparam.h
+++ b/include/linux/moduleparam.h
@@ -78,6 +78,7 @@ struct kernel_param {
const struct kparam_string *str;
const struct kparam_array *arr;
};
+   const void *data;
 };
 
 extern const struct kernel_param __start___param[], __stop___param[];
@@ -175,6 +176,9 @@ struct kparam_array
 #define module_param_cb(name, ops, arg, perm)\
__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1, 0)
 
+#define module_param_cbd(name, ops, arg, perm, data)   
\
+   __module_param_call_wdata(MODULE_PARAM_PREFIX, name, ops, arg, perm, 
-1, 0, data)
+
 #define module_param_cb_unsafe(name, ops, arg, perm) \
__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1,\
KERNEL_PARAM_FL_UNSAFE)
@@ -284,14 +288,17 @@ struct kparam_array
 
 /* This is the fundamental function for registering boot/module
parameters. */
-#define __module_param_call(prefix, name, ops, arg, perm, level, flags)
\
+#define __module_param_call(prefix, name, ops, arg, perm, level, flags) \
+   __module_param_call_wdata(prefix, name, ops, arg, perm, level, flags, 
NULL)
+
+#define __module_param_call_wdata(prefix, name, ops, arg, perm, level, flags, 
data) \
/* Default value instead of permissions? */ \
static const char __param_str_##name[] = prefix #name;  \
static struct kernel_param __moduleparam_const __param_##name   \
__used __section("__param") \
__aligned(__alignof__(struct kernel_param)) \
= { __param_str_##name, THIS_MODULE, ops,   \
-   VERIFY_OCTAL_PERMISSIONS(perm), level, flags, { arg } }
+   VERIFY_OCTAL_PERMISSIONS(perm), level, flags, { arg }, data }
 
 /* Obsolete - use module_param_cb() */
 #define module_param_call(name, _set, _get, arg, perm) \
-- 
2.31.1