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Date:   Thu, 12 Jan 2023 17:54:21 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Andreas Gruenbacher <agruenba@redhat.com>
Cc:     Josef Bacik <josef@redhat.com>, Jan Kara <jack@suse.cz>,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 2/3] fs: Introduce { freeze, thaw }_active_super functions
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References: <20221129230736.3462830-1-agruenba@redhat.com>
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On Wed, Nov 30, 2022 at 12:07:34AM +0100, Andreas Gruenbacher wrote:

> -int freeze_super(struct super_block *sb)
> +int freeze_active_super(struct super_block *sb)
>  {
>  	int ret;
>  
> -	atomic_inc(&sb->s_active);
>  	down_write(&sb->s_umount);
>  	if (sb->s_writers.frozen != SB_UNFROZEN) {
>  		deactivate_locked_super(sb);

Not fond of the calling conventions, to be honest...  "On success return 0;
on failure return -E... *and* drop an active reference passed by the caller"?

If you go that way, at least take the deactivate_locked_super() into the
caller and I would argue that ->s_umount handling also belongs in the caller,
both grabbing and dropping it.