linux-kernel - Re: [PATCH 03/13] vfs: add try_break_deleg calls for parents to vfs

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Message-ID: <n5ihwvsits3u7fwvzuk42vmqdv45ap6u4gh77diegtxik42emp@whyfqmynxnl2>
Date: Mon, 20 Oct 2025 11:38:14 +0200
From: Jan Kara <jack@...e.cz>
To: Jeff Layton <jlayton@...nel.org>
Cc: Miklos Szeredi <miklos@...redi.hu>, 
	Alexander Viro <viro@...iv.linux.org.uk>, Christian Brauner <brauner@...nel.org>, Jan Kara <jack@...e.cz>, 
	Chuck Lever <chuck.lever@...cle.com>, Alexander Aring <alex.aring@...il.com>, 
	Trond Myklebust <trondmy@...nel.org>, Anna Schumaker <anna@...nel.org>, 
	Steve French <sfrench@...ba.org>, Paulo Alcantara <pc@...guebit.org>, 
	Ronnie Sahlberg <ronniesahlberg@...il.com>, Shyam Prasad N <sprasad@...rosoft.com>, 
	Tom Talpey <tom@...pey.com>, Bharath SM <bharathsm@...rosoft.com>, 
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>, "Rafael J. Wysocki" <rafael@...nel.org>, 
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	netdev@...r.kernel.org
Subject: Re: [PATCH 03/13] vfs: add try_break_deleg calls for parents to
 vfs_{link,rename,unlink}

On Mon 13-10-25 10:48:01, Jeff Layton wrote:
> In order to add directory delegation support, we need to break
> delegations on the parent whenever there is going to be a change in the
> directory.
> 
> vfs_link, vfs_unlink, and vfs_rename all have existing delegation break
> handling for the children in the rename. Add the necessary calls for
> breaking delegations in the parent(s) as well.
> 
> Signed-off-by: Jeff Layton <jlayton@...nel.org>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@...e.cz>

								Honza

> ---
>  fs/namei.c | 15 ++++++++++++++-
>  1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/namei.c b/fs/namei.c
> index 7377020a2cba02501483020e0fc93c279fb38d3e..6e61e0215b34134b1690f864e2719e3f82cf71a8 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -4667,6 +4667,9 @@ int vfs_unlink(struct mnt_idmap *idmap, struct inode *dir,
>  	else {
>  		error = security_inode_unlink(dir, dentry);
>  		if (!error) {
> +			error = try_break_deleg(dir, delegated_inode);
> +			if (error)
> +				goto out;
>  			error = try_break_deleg(target, delegated_inode);
>  			if (error)
>  				goto out;
> @@ -4936,7 +4939,9 @@ int vfs_link(struct dentry *old_dentry, struct mnt_idmap *idmap,
>  	else if (max_links && inode->i_nlink >= max_links)
>  		error = -EMLINK;
>  	else {
> -		error = try_break_deleg(inode, delegated_inode);
> +		error = try_break_deleg(dir, delegated_inode);
> +		if (!error)
> +			error = try_break_deleg(inode, delegated_inode);
>  		if (!error)
>  			error = dir->i_op->link(old_dentry, dir, new_dentry);
>  	}
> @@ -5203,6 +5208,14 @@ int vfs_rename(struct renamedata *rd)
>  		    old_dir->i_nlink >= max_links)
>  			goto out;
>  	}
> +	error = try_break_deleg(old_dir, delegated_inode);
> +	if (error)
> +		goto out;
> +	if (new_dir != old_dir) {
> +		error = try_break_deleg(new_dir, delegated_inode);
> +		if (error)
> +			goto out;
> +	}
>  	if (!is_dir) {
>  		error = try_break_deleg(source, delegated_inode);
>  		if (error)
> 
> -- 
> 2.51.0
> 
-- 
Jan Kara <jack@...e.com>
SUSE Labs, CR