[PATCH drm-next v4 02/14] maple_tree: split up MA_STATE() macro

[Liam R. Howlett]

* Danilo Krummrich <dakr at redhat.com> [230606 18:31]:
> Split up the MA_STATE() macro such that components using the maple tree
> can easily inherit from struct ma_state and build custom tree walk
> macros to hide their internals from users.
> 
> Example:
> 
> struct sample_iterator {
> 	struct ma_state mas;
> 	struct sample_mgr *mgr;
> };
> 
> \#define SAMPLE_ITERATOR(name, __mgr, start)			\
> 	struct sample_iterator name = {				\
> 		.mas = MA_STATE_INIT(&(__mgr)->mt, start, 0),	\
> 		.mgr = __mgr,					\
> 	}
> 
> \#define sample_iter_for_each_range(it__, entry__, end__) \
> 	mas_for_each(&(it__).mas, entry__, end__)
> 
> --
> 
> struct sample *sample;
> SAMPLE_ITERATOR(si, min);
> 
> sample_iter_for_each_range(&si, sample, max) {
> 	frob(mgr, sample);
> }
> 
> Signed-off-by: Danilo Krummrich <dakr at redhat.com>

Reviewed-by: Liam R. Howlett <Liam.Howlett at oracle.com>

> ---
>  include/linux/maple_tree.h | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h
> index 1fadb5f5978b..87d55334f1c2 100644
> --- a/include/linux/maple_tree.h
> +++ b/include/linux/maple_tree.h
> @@ -423,8 +423,8 @@ struct ma_wr_state {
>  #define MA_ERROR(err) \
>  		((struct maple_enode *)(((unsigned long)err << 2) | 2UL))
>  
> -#define MA_STATE(name, mt, first, end)					\
> -	struct ma_state name = {					\
> +#define MA_STATE_INIT(mt, first, end)					\
> +	{								\
>  		.tree = mt,						\
>  		.index = first,						\
>  		.last = end,						\
> @@ -435,6 +435,9 @@ struct ma_wr_state {
>  		.mas_flags = 0,						\
>  	}
>  
> +#define MA_STATE(name, mt, first, end)					\
> +	struct ma_state name = MA_STATE_INIT(mt, first, end)
> +
>  #define MA_WR_STATE(name, ma_state, wr_entry)				\
>  	struct ma_wr_state name = {					\
>  		.mas = ma_state,					\
> -- 
> 2.40.1
> 
>