Regionlist overhaul: Shrink struct regl

src/fellow_regionlist.h

@@ -45,7 +45,7 @@
 struct regl {
 	unsigned			magic;
 #define REGL_MAGIC			0xe946b3c2
-	unsigned			n, space;
+	uint16_t			n, space;
 	struct buddy_ptr_page		alloc;
 	VSTAILQ_ENTRY(regl)		list;
 	struct buddy_off_extent	arr[];
@@ -150,8 +150,8 @@ regl_alloc_bits(buddy_t *membuddy, const uint8_t bits, int8_t cram,
 
 	r->magic = REGL_MAGIC;
 	b = sz / sizeof *r->arr;
-	assert(b <= UINT_MAX);
-	r->space = (unsigned)b;
+	assert(b <= UINT16_MAX);
+	r->space = (typeof(r->space))b;
 	r->alloc = alloc;
 	return (r);
 }
@@ -222,7 +222,7 @@ regionlist_add(struct regionlist *rl,
     const struct buddy_off_extent *regs, unsigned n)
 {
 	struct regl *regl;
-	unsigned av, nn;
+	uint16_t av, nn;
 
 	CHECK_OBJ_NOTNULL(rl, REGIONLIST_MAGIC);
 	regl = VSTAILQ_LAST(&rl->head, regl, list);
@@ -240,7 +240,7 @@ regionlist_add(struct regionlist *rl,
 		if (av < n)
 			nn = av;
 		else
-			nn = n;
+			nn = (typeof(nn))n;
 
 		memcpy(&regl->arr[regl->n], regs, nn * sizeof *regs);
 		regl->n += nn;