From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id B8BEB6B0033 for ; Fri, 27 Oct 2017 05:13:04 -0400 (EDT) Received: by mail-wm0-f69.google.com with SMTP id n8so3028836wmg.4 for ; Fri, 27 Oct 2017 02:13:04 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id g13si5392290wrh.413.2017.10.27.02.13.03 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 27 Oct 2017 02:13:03 -0700 (PDT) Date: Fri, 27 Oct 2017 11:13:01 +0200 From: Jan Kara Subject: Re: [PATCH 17/17] xfs: support for synchronous DAX faults Message-ID: <20171027091301.GG31161@quack2.suse.cz> References: <20171024152415.22864-1-jack@suse.cz> <20171024152415.22864-18-jack@suse.cz> <20171024222322.GX3666@dastard> <20171026154804.GF31161@quack2.suse.cz> <20171027064301.GC22931@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171027064301.GC22931@lst.de> Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Hellwig Cc: Jan Kara , Dave Chinner , Dan Williams , Ross Zwisler , Christoph Hellwig , linux-ext4@vger.kernel.org, linux-nvdimm@lists.01.org, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-api@vger.kernel.org, linux-mm@kvack.org On Fri 27-10-17 08:43:01, Christoph Hellwig wrote: > On Thu, Oct 26, 2017 at 05:48:04PM +0200, Jan Kara wrote: > > But now that I look at XFS implementation again, it misses handling > > of VM_FAULT_NEEDSYNC in xfs_filemap_pfn_mkwrite() (ext4 gets this right). > > I'll fix this by using __xfs_filemap_fault() for xfs_filemap_pfn_mkwrite() > > as well since it mostly duplicates it anyway... Thanks for inquiring! > > My first patches move xfs_filemap_pfn_mkwrite to use __xfs_filemap_fault, > but that didn't work. Wish I'd remember why, though. Maybe due to the additional check on IS_DAX(inode) in __xfs_filemap_fault() which could do the wrong thing if per-inode DAX flag is switched? Because otherwise __xfs_filemap_fault(vmf, PE_SIZE_PTE, true) does exactly the same thing as xfs_filemap_pfn_mkwrite() did. If we do care about per-inode DAX flag switching, I can just fixup xfs_filemap_pfn_mkwrite() but my understanding was that we ditched the idea at least until someone comes up with a reliable way to implement that... Honza -- Jan Kara SUSE Labs, CR -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org