Re: [PATCH v2] riscv: Use PMD_SIZE to repalce PTE_PARENT_SIZE

From: Christoph Hellwig
Date: Fri Nov 08 2019 - 02:25:25 EST


On Mon, Nov 04, 2019 at 06:20:12PM -0800, Zong Li wrote:
> uintptr_t map_size = PAGE_SIZE;
>
> - /* Upgrade to PMD/PGDIR mappings whenever possible */
> - if (!(base & (PTE_PARENT_SIZE - 1)) &&
> - !(size & (PTE_PARENT_SIZE - 1)))
> - map_size = PTE_PARENT_SIZE;
> + /* Upgrade to PMD_SIZE mappings whenever possible */
> + if (!(base & (PMD_SIZE - 1)) &&
> + !(size & (PMD_SIZE - 1)))
> + map_size = PMD_SIZE;

The check easily fits onto a single line now. Also the map_size
variable is rather pointless. Why not:

if ((base & (PMD_SIZE - 1) || (size & (PMD_SIZE - 1)))
return PAGE_SIZE;
return PMD_SIZE;