Re: [f2fs-dev] [PATCH] f2fs: get parent inode when recovering pino

[Eric Biggers]

On Tue, May 05, 2020 at 11:49:32AM -0700, Jaegeuk Kim wrote:
> How about this?
> 
> From 2a6b0e53e592854306062a2dc35db2d8f79062f2 Mon Sep 17 00:00:00 2001
> From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> Date: Tue, 5 May 2020 11:33:29 -0700
> Subject: [PATCH] f2fs: find a living dentry when finding parent ino
> 
> We need to check any dentry still alive to get parent inode number.
> 
> Suggested-by: Eric Biggers <ebiggers@xxxxxxxxxx>
> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> ---
>  fs/f2fs/file.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index a0a4413d6083b..95139cb85faca 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -169,9 +169,8 @@ static int get_parent_ino(struct inode *inode, nid_t *pino)
>  {
>  	struct dentry *dentry;
>  
> -	inode = igrab(inode);
> -	dentry = d_find_any_alias(inode);
> -	iput(inode);
> +	/* Need to check if valid dentry still exists. */
> +	dentry = d_find_alias(inode);
>  	if (!dentry)
>  		return 0;
>  

It's fine, but it could use some more explanation.  (What's a "valid dentry"?)
How about the following?