Re: [RFC PATCH] fs: introduce ST_HUGE flag and set it to tmpfs and hugetlbfs

From: Matthew Wilcox
Date: Tue Apr 17 2018 - 19:23:15 EST

On Wed, Apr 18, 2018 at 05:08:13AM +0800, Yang Shi wrote:
> When applications use huge page on hugetlbfs, it just need check the
> filesystem magic number, but it is not enough for tmpfs. So, introduce
> ST_HUGE flag to statfs if super block has SB_HUGE set which indicates
> huge page is supported on the specific filesystem.

Hm. What's the plan for communicating support for page sizes other
than PMD page sizes? I know ARM has several different page sizes,
as do PA-RISC and ia64. Even x86 might support 1G page sizes through
tmpfs one day.