Re: [PATCH 1/5] VFS: merge lookup_one_qstr_excl_raw() back into lookup_one_qstr_excl()

[Jeff Layton <jlayton@kernel.org>]

On Mon, 2025-06-09 at 09:09 +1000, NeilBrown wrote:
> The effect of lookup_one_qstr_excl_raw() can be achieved by passing
> LOOKUP_CREATE() to lookup_one_qstr_excl() - we don't need a separate
> function.
> 
> Signed-off-by: NeilBrown <neil@brown.name>
> ---
>  fs/namei.c | 37 ++++++++++++++-----------------------
>  1 file changed, 14 insertions(+), 23 deletions(-)
> 
> diff --git a/fs/namei.c b/fs/namei.c
> index 4bb889fc980b..dc42bfac5c57 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -1665,9 +1665,17 @@ static struct dentry *lookup_dcache(const struct qstr *name,
>  	return dentry;
>  }
>  
> -static struct dentry *lookup_one_qstr_excl_raw(const struct qstr *name,
> -					       struct dentry *base,
> -					       unsigned int flags)
> +/*
> + * Parent directory has inode locked exclusive.  This is one
> + * and only case when ->lookup() gets called on non in-lookup
> + * dentries - as the matter of fact, this only gets called
> + * when directory is guaranteed to have no in-lookup children
> + * at all.
> + * Will return -ENOENT if name isn't found and LOOKUP_CREATE wasn't passed.
> + * Will return -EEXIST if name is found and LOOKUP_EXCL was passed.
> + */
> +struct dentry *lookup_one_qstr_excl(const struct qstr *name,
> +				    struct dentry *base, unsigned int flags)
>  {
>  	struct dentry *dentry;
>  	struct dentry *old;
> @@ -1675,7 +1683,7 @@ static struct dentry *lookup_one_qstr_excl_raw(const struct qstr *name,
>  
>  	dentry = lookup_dcache(name, base, flags);
>  	if (dentry)
> -		return dentry;
> +		goto found;
>  
>  	/* Don't create child dentry for a dead directory. */
>  	dir = base->d_inode;
> @@ -1691,24 +1699,7 @@ static struct dentry *lookup_one_qstr_excl_raw(const struct qstr *name,
>  		dput(dentry);
>  		dentry = old;
>  	}
> -	return dentry;
> -}
> -
> -/*
> - * Parent directory has inode locked exclusive.  This is one
> - * and only case when ->lookup() gets called on non in-lookup
> - * dentries - as the matter of fact, this only gets called
> - * when directory is guaranteed to have no in-lookup children
> - * at all.
> - * Will return -ENOENT if name isn't found and LOOKUP_CREATE wasn't passed.
> - * Will return -EEXIST if name is found and LOOKUP_EXCL was passed.
> - */
> -struct dentry *lookup_one_qstr_excl(const struct qstr *name,
> -				    struct dentry *base, unsigned int flags)
> -{
> -	struct dentry *dentry;
> -
> -	dentry = lookup_one_qstr_excl_raw(name, base, flags);
> +found:
>  	if (IS_ERR(dentry))
>  		return dentry;
>  	if (d_is_negative(dentry) && !(flags & LOOKUP_CREATE)) {
> @@ -2790,7 +2781,7 @@ struct dentry *kern_path_locked_negative(const char *name, struct path *path)
>  	if (unlikely(type != LAST_NORM))
>  		return ERR_PTR(-EINVAL);
>  	inode_lock_nested(parent_path.dentry->d_inode, I_MUTEX_PARENT);
> -	d = lookup_one_qstr_excl_raw(&last, parent_path.dentry, 0);
> +	d = lookup_one_qstr_excl(&last, parent_path.dentry, LOOKUP_CREATE);
>  	if (IS_ERR(d)) {
>  		inode_unlock(parent_path.dentry->d_inode);
>  		return d;

Nice little cleanup.

Reviewed-by: Jeff Layton <jlayton@kernel.org>