From patchwork Tue May 8 18:04:33 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Fasheh X-Patchwork-Id: 10386899 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 486FD60353 for ; Tue, 8 May 2018 18:08:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2C56628E37 for ; Tue, 8 May 2018 18:08:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 21B2028ECB; Tue, 8 May 2018 18:08:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BFDBB28EAE for ; Tue, 8 May 2018 18:08:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933061AbeEHSGg (ORCPT ); Tue, 8 May 2018 14:06:36 -0400 Received: from mx2.suse.de ([195.135.220.15]:54289 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933046AbeEHSGf (ORCPT ); Tue, 8 May 2018 14:06:35 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 0C391AD4A; Tue, 8 May 2018 18:06:34 +0000 (UTC) From: Mark Fasheh To: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, Mark Fasheh Subject: [PATCH 73/76] vfs: Move s_dev to to struct fs_view Date: Tue, 8 May 2018 11:04:33 -0700 Message-Id: <20180508180436.716-74-mfasheh@suse.de> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180508180436.716-1-mfasheh@suse.de> References: <20180508180436.716-1-mfasheh@suse.de> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP There are many places where a dev_t:ino_t pair are passed to userspace to uniquely describe an inode. Some file systems, like btrfs, have multiple inode namespace internally and use a separate dev_t to make the distinction between them. The kernel typically uses sb->s_dev for the inode device. Most filesystems are fine with that but btrfs needs to use the device beloning to the root which that inode resides on. By moving s_dev into the fs_view we allow btrfs and any similar filesystems to set this field on a per inode basis. This patch adds a dev_t field to struct fs_view, v_dev and removes s_dev from struct super_block. I also include a helper, inode_view() to make referencing inode->i_view fields less clunky. Signed-off-by: Mark Fasheh --- include/linux/fs.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index 5d4bb19b2a43..c93486505084 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1351,6 +1351,7 @@ struct sb_writers { */ struct fs_view { struct super_block *v_sb; + dev_t v_dev; /* search index; _not_ kdev_t */ }; static inline struct super_block *inode_sb(const struct inode *inode) @@ -1358,9 +1359,13 @@ static inline struct super_block *inode_sb(const struct inode *inode) return inode->i_view->v_sb; } +static inline struct fs_view *inode_view(const struct inode *inode) +{ + return inode->i_view; +} + struct super_block { struct list_head s_list; /* Keep this first */ - dev_t s_dev; /* search index; _not_ kdev_t */ unsigned char s_blocksize_bits; unsigned long s_blocksize; loff_t s_maxbytes; /* Max file size */