| Message ID | 20210822222009.2035788-2-jim.cromie@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | use DYNAMIC_DEBUG to implement DRM.debug | expand |
On 8/22/21 6:19 PM, 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_cb_data() derives from module_param_cb(), adding data > param, and latter is redefined to use former. > > It calls __module_param_call_with_data(), which accepts 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. > > Signed-off-by: Jim Cromie <jim.cromie@gmail.com> > --- > v6: > . const void* data - <emil.l.velikov@gmail.com> > . better macro names s/_cbd/_cb_data/, s/_wdata/_with_data/ > . more const, no cast - Willy > --- > 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..b8871e514de5 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; > }; > I wonder if kp->arg can just be used for all this and avoid this patch entirely? define something like: struct dd_bitmap_param { int bitmap; struct dyndbg_bitdesc *bitmap_arr; }; and then just pass a pointer to it as 'arg' for module_param_cb? And then in the get/set callbacks you can use kp->bitmap and kp->bitmap_arr. Thanks, -Jason > 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_cb_data(name, ops, arg, perm, data) \ > + __module_param_call_with_data(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_with_data(prefix, name, ops, arg, perm, level, flags, NULL) > + > +#define __module_param_call_with_data(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) \ >
On Wed, Aug 25, 2021 at 11:13 AM Jason Baron <jbaron@akamai.com> wrote: > > > > On 8/22/21 6:19 PM, 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: > > > > I wonder if kp->arg can just be used for all this and avoid this patch entirely? > > define something like: > > struct dd_bitmap_param { > int bitmap; > struct dyndbg_bitdesc *bitmap_arr; > }; > > and then just pass a pointer to it as 'arg' for module_param_cb? And then in > the get/set callbacks you can use kp->bitmap and kp->bitmap_arr. > yes, thanks, this is working out nicely. I think I was thrown off by the arg name, if it had been called data, it would have slapped me > Thanks, > > -Jason >
diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index eed280fae433..b8871e514de5 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_cb_data(name, ops, arg, perm, data) \ + __module_param_call_with_data(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_with_data(prefix, name, ops, arg, perm, level, flags, NULL) + +#define __module_param_call_with_data(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) \
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_cb_data() derives from module_param_cb(), adding data param, and latter is redefined to use former. It calls __module_param_call_with_data(), which accepts 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. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- v6: . const void* data - <emil.l.velikov@gmail.com> . better macro names s/_cbd/_cb_data/, s/_wdata/_with_data/ . more const, no cast - Willy --- include/linux/moduleparam.h | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)