From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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> In-Reply-To: <20180508180436.716-1-mfasheh@suse.de> References: <20180508180436.716-1-mfasheh@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: 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 */ -- 2.15.1