From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f70.google.com (mail-pl0-f70.google.com [209.85.160.70]) by kanga.kvack.org (Postfix) with ESMTP id 5731A6B0005 for ; Tue, 17 Apr 2018 19:23:01 -0400 (EDT) Received: by mail-pl0-f70.google.com with SMTP id b11-v6so13254740pla.19 for ; Tue, 17 Apr 2018 16:23:01 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [2607:7c80:54:e::133]) by mx.google.com with ESMTPS id f7si12351786pgn.476.2018.04.17.16.22.59 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 17 Apr 2018 16:22:59 -0700 (PDT) Date: Tue, 17 Apr 2018 16:22:48 -0700 From: Matthew Wilcox Subject: Re: [RFC PATCH] fs: introduce ST_HUGE flag and set it to tmpfs and hugetlbfs Message-ID: <20180417232248.GA27631@bombadil.infradead.org> References: <1523999293-94152-1-git-send-email-yang.shi@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1523999293-94152-1-git-send-email-yang.shi@linux.alibaba.com> Sender: owner-linux-mm@kvack.org List-ID: To: Yang Shi Cc: viro@zeniv.linux.org.uk, nyc@holomorphy.com, mike.kravetz@oracle.com, kirill.shutemov@linux.intel.com, hughd@google.com, akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org 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.