Re: [PATCH v3 06/10] debugfs: simplify __debugfs_remove_file()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Sun, May 26, 2019 at 05:34:07PM +0300, Amir Goldstein wrote:
> Move simple_unlink()+d_delete() from __debugfs_remove_file() into
> caller __debugfs_remove() and rename helper for post remove file to
> __debugfs_file_removed().
> 
> This will simplify adding fsnotify_unlink() hook.
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
> ---
>  fs/debugfs/inode.c | 20 ++++++++------------
>  1 file changed, 8 insertions(+), 12 deletions(-)
> 
> diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
> index acef14ad53db..d89874da9791 100644
> --- a/fs/debugfs/inode.c
> +++ b/fs/debugfs/inode.c
> @@ -617,13 +617,10 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
>  }
>  EXPORT_SYMBOL_GPL(debugfs_create_symlink);
>  
> -static void __debugfs_remove_file(struct dentry *dentry, struct dentry *parent)
> +static void __debugfs_file_removed(struct dentry *dentry)
>  {
>  	struct debugfs_fsdata *fsd;
>  
> -	simple_unlink(d_inode(parent), dentry);
> -	d_delete(dentry);
> -
>  	/*
>  	 * Paired with the closing smp_mb() implied by a successful
>  	 * cmpxchg() in debugfs_file_get(): either
> @@ -644,16 +641,15 @@ static int __debugfs_remove(struct dentry *dentry, struct dentry *parent)
>  
>  	if (simple_positive(dentry)) {
>  		dget(dentry);
> -		if (!d_is_reg(dentry)) {
> -			if (d_is_dir(dentry))
> -				ret = simple_rmdir(d_inode(parent), dentry);
> -			else
> -				simple_unlink(d_inode(parent), dentry);
> -			if (!ret)
> -				d_delete(dentry);
> +		if (d_is_dir(dentry)) {
> +			ret = simple_rmdir(d_inode(parent), dentry);
>  		} else {
> -			__debugfs_remove_file(dentry, parent);
> +			simple_unlink(d_inode(parent), dentry);
>  		}
> +		if (!ret)
> +			d_delete(dentry);
> +		if (d_is_reg(dentry))
> +			__debugfs_file_removed(dentry);
>  		dput(dentry);
>  	}
>  	return ret;

Ugh, I had to stare at this for a long time.  I _think_ it all looks
equalivant now, but if this breaks, I know who to blame :)

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>