(*pageBits)(b).setRange(i, n)
}

// allocAll allocates all the bits of b.
func (b *pallocBits) allocAll() {
	(*pageBits)(b).setAll()
}

// free1 frees a single page in the pallocBits at i.
func (b *pallocBits) free1(i uint) {
	(*pageBits)(b).clear(i)
}

// free frees the range [i, i+n) of pages in the pallocBits.
func (b *pallocBits) free(i, n uint) {
	(*pageBits)(b).clearRange(i, n)
}

	if npages == 1 {
		// Fast path: we're clearing a single bit, and we know exactly
		// where it is, so mark it directly.
		i := chunkIndex(base)
		pi := chunkPageIndex(base)
		p.chunkOf(i).free1(pi)
		p.scav.index.free(i, pi, 1)
	} else {
		// Slow path: we're clearing more bits so we may need to iterate.
		sc, ec := chunkIndex(base), chunkIndex(limit)
		si, ei := chunkPageIndex(base), chunkPageIndex(limit)