malloc: add a helper returning size allocated for given request

Sample usage: kernel modules can decide whether to stick to malloc or
create their own zone.

Reviewed by:	markj
Differential Revision:	https://reviews.freebsd.org/D27097

1 files changed, 1 insertions, 0 deletions

diff --git a/sys/sys/malloc.h b/sys/sys/malloc.h
index c13ebaacbf6e..a793b1d77797 100644
--- a/sys/sys/malloc.h
+++ b/sys/sys/malloc.h
@@ -250,6 +250,7 @@ void	malloc_type_allocated(struct malloc_type *type, unsigned long size);
 void	malloc_type_freed(struct malloc_type *type, unsigned long size);
 void	malloc_type_list(malloc_type_list_func_t *, void *);
 void	malloc_uninit(void *);
+size_t	malloc_size(size_t);
 size_t	malloc_usable_size(const void *);
 void	*realloc(void *addr, size_t size, struct malloc_type *type, int flags)
 	    __result_use_check __alloc_size(2);