From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68B02C282E1 for ; Thu, 23 May 2019 13:44:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 44C8420881 for ; Thu, 23 May 2019 13:44:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730706AbfEWNov (ORCPT ); Thu, 23 May 2019 09:44:51 -0400 Received: from mx2.suse.de ([195.135.220.15]:50416 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730081AbfEWNov (ORCPT ); Thu, 23 May 2019 09:44:51 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 6207AAC6E; Thu, 23 May 2019 13:44:50 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 010F11E3C69; Thu, 23 May 2019 15:44:49 +0200 (CEST) Date: Thu, 23 May 2019 15:44:49 +0200 From: Jan Kara To: Goldwyn Rodrigues Cc: linux-btrfs@vger.kernel.org, kilobyte@angband.pl, linux-fsdevel@vger.kernel.org, jack@suse.cz, david@fromorbit.com, willy@infradead.org, hch@lst.de, darrick.wong@oracle.com, dsterba@suse.cz, nborisov@suse.com, linux-nvdimm@lists.01.org, Goldwyn Rodrigues Subject: Re: [PATCH 12/18] btrfs: allow MAP_SYNC mmap Message-ID: <20190523134449.GC2949@quack2.suse.cz> References: <20190429172649.8288-1-rgoldwyn@suse.de> <20190429172649.8288-13-rgoldwyn@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190429172649.8288-13-rgoldwyn@suse.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon 29-04-19 12:26:43, Goldwyn Rodrigues wrote: > From: Adam Borowski > > Used by userspace to detect DAX. > [rgoldwyn@suse.com: Added CONFIG_FS_DAX around mmap_supported_flags] Why the CONFIG_FS_DAX bit? Your mmap(2) implementation understands implications of MAP_SYNC flag and that's all that's needed to set .mmap_supported_flags. Honza > Signed-off-by: Adam Borowski > Signed-off-by: Goldwyn Rodrigues > --- > fs/btrfs/file.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > index 9d5a3c99a6b9..362a9cf9dcb2 100644 > --- a/fs/btrfs/file.c > +++ b/fs/btrfs/file.c > @@ -16,6 +16,7 @@ > #include > #include > #include > +#include > #include "ctree.h" > #include "disk-io.h" > #include "transaction.h" > @@ -3319,6 +3320,9 @@ const struct file_operations btrfs_file_operations = { > .splice_read = generic_file_splice_read, > .write_iter = btrfs_file_write_iter, > .mmap = btrfs_file_mmap, > +#ifdef CONFIG_FS_DAX > + .mmap_supported_flags = MAP_SYNC, > +#endif > .open = btrfs_file_open, > .release = btrfs_release_file, > .fsync = btrfs_sync_file, > -- > 2.16.4 > -- Jan Kara SUSE Labs, CR