RE: [PATCH 1/2] f2fs: introduce f2fs_do_tmpfile for code consistency

Chao Yu
2014-06-23T03:14:06Z

Hi,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Monday, June 23, 2014 9:13 AM
> To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org;
> linux-f2fs-devel@lists.sourceforge.net
> Cc: Jaegeuk Kim; Chao Yu
> Subject: [PATCH 1/2] f2fs: introduce f2fs_do_tmpfile for code consistency
>
> This patch adds f2fs_do_tmpfile to eliminate the redundant init_inode_metadata
> flow.
> Throught this, we can provide the consistent lock usage, e.g., fi->i_sem, and
> this will enable better debugging stuffs.
>
> Cc: Chao Yu <chao2.yu@samsung.com>
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
> fs/f2fs/dir.c | 27 ++++++++++++++++++++++++---
> fs/f2fs/f2fs.h | 1 +
> fs/f2fs/namei.c | 30 ++++++++----------------------
> 3 files changed, 33 insertions(+), 25 deletions(-)
>
> diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
> index 09760d5..fe6aaca 100644
> --- a/fs/f2fs/dir.c
> +++ b/fs/f2fs/dir.c
> @@ -337,8 +337,7 @@ static struct page *init_inode_metadata(struct inode *inode,
> struct page *page;
> int err;
>
> - if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE) &&
> - inode->i_nlink) {
> + if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
> page = new_inode_page(inode, name);
> if (IS_ERR(page))
> return page;
> @@ -364,7 +363,8 @@ static struct page *init_inode_metadata(struct inode *inode,
> set_cold_node(inode, page);
> }
>
> - init_dent_inode(name, page);
> + if (name)
> + init_dent_inode(name, page);
>
> /*
> * This file should be checkpointed during fsync.
> @@ -537,6 +537,27 @@ fail:
> return err;
> }
>
> +int f2fs_do_tmpfile(struct inode *inode, struct inode *dir)
> +{
> + struct page *page;
> + int err = 0;
> +
> + down_write(&F2FS_I(inode)->i_sem);

Here I did not find nlink/pino/xattr_ver which we should protect by ->i_sem,
Am I missing something?

> + page = init_inode_metadata(inode, dir, NULL);
> + if (IS_ERR(page)) {
> + err = PTR_ERR(page);
> + goto fail;
> + }
> + /* we don't need to mark_inode_dirty now */
> + update_inode(inode, page);
> + f2fs_put_page(page, 1);
> +
> + update_parent_metadata(dir, inode, F2FS_I(dir)->i_current_depth);

Things we did in update_parent_metadata() is: 1.clear FI_NEW_INODE of inode flag,
2. update mtime&ctime of dir and mark it dirty.
IMO, we do not need the update op because we do not access/modify current dir
as we did normally through f2fs_add_link path.
So how about using clear_inode_flag instead of update_parent_metadata and leave
current dir as clean?

Thanks,
Yu

> +fail:
> + up_write(&F2FS_I(inode)->i_sem);
> + return err;
> +}
> +
> /*
> * It only removes the dentry from the dentry page,corresponding name
> * entry in name page does not need to be touched during deletion.
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 58df97e..ca421a8 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -1136,6 +1136,7 @@ void f2fs_set_link(struct inode *, struct f2fs_dir_entry *,
> int update_dent_inode(struct inode *, const struct qstr *);
> int __f2fs_add_link(struct inode *, const struct qstr *, struct inode *);
> void f2fs_delete_entry(struct f2fs_dir_entry *, struct page *, struct inode *);
> +int f2fs_do_tmpfile(struct inode *, struct inode *);
> int f2fs_make_empty(struct inode *, struct inode *);
> bool f2fs_empty_dir(struct inode *);
>
> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
> index 0d55517..9de4ab3 100644
> --- a/fs/f2fs/namei.c
> +++ b/fs/f2fs/namei.c
> @@ -494,7 +494,6 @@ static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t
> mode)
> struct super_block *sb = dir->i_sb;
> struct f2fs_sb_info *sbi = F2FS_SB(sb);
> struct inode *inode;
> - struct page *page;
> int err;
>
> inode = f2fs_new_inode(dir, mode);
> @@ -509,38 +508,25 @@ static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t
> mode)
> err = acquire_orphan_inode(sbi);
> if (err)
> goto out;
> +
> + err = f2fs_do_tmpfile(inode, dir);
> + if (err)
> + goto release_out;
> +
> /*
> * add this non-linked tmpfile to orphan list, in this way we could
> * remove all unused data of tmpfile after abnormal power-off.
> */
> add_orphan_inode(sbi, inode->i_ino);
> -
> - page = new_inode_page(inode, NULL);
> - if (IS_ERR(page)) {
> - err = PTR_ERR(page);
> - goto remove_out;
> - }
> -
> - err = f2fs_init_acl(inode, dir, page);
> - if (err)
> - goto unlock_out;
> -
> - err = f2fs_init_security(inode, dir, NULL, page);
> - if (err)
> - goto unlock_out;
> -
> - f2fs_put_page(page, 1);
> f2fs_unlock_op(sbi);
>
> alloc_nid_done(sbi, inode->i_ino);
> - mark_inode_dirty(inode);
> d_tmpfile(dentry, inode);
> unlock_new_inode(inode);
> return 0;
> -unlock_out:
> - f2fs_put_page(page, 1);
> -remove_out:
> - remove_orphan_inode(sbi, inode->i_ino);
> +
> +release_out:
> + release_orphan_inode(sbi);
> out:
> f2fs_unlock_op(sbi);
> clear_nlink(inode);
> --
> 1.8.5.2 (Apple Git-48)