linux-kernel - Re: [PATCH v2 3/5] xfs: Replace xfs_isilocked with xfs_assert

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <ZSMmQm/DbJQ0/oH9@dread.disaster.area>
Date:   Mon, 9 Oct 2023 08:59:30 +1100
From:   Dave Chinner <david@...morbit.com>
To:     "Matthew Wilcox (Oracle)" <willy@...radead.org>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>, Will Deacon <will@...nel.org>,
        Waiman Long <longman@...hat.com>, linux-kernel@...r.kernel.org,
        linux-mm@...ck.org, Chandan Babu R <chandan.babu@...cle.com>,
        "Darrick J . Wong" <djwong@...nel.org>, linux-xfs@...r.kernel.org,
        Mateusz Guzik <mjguzik@...il.com>
Subject: Re: [PATCH v2 3/5] xfs: Replace xfs_isilocked with xfs_assert_locked

On Sat, Oct 07, 2023 at 09:35:41PM +0100, Matthew Wilcox (Oracle) wrote:
> To use the new rwsem_assert_held()/rwsem_assert_held_write(), we can't
> use the existing ASSERT macro.
> 
> xfs_assert_ilocked(ip,  XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL) checks both the
> IOLOCK and the ILOCK are held for write.  xfs_isilocked() only checked
> that the ILOCK was held for write.
> 
> xfs_assert_ilocked() is always on, even if DEBUG or XFS_WARN aren't
> defined.  It's a cheap check, so I don't think it's worth defining
> it away.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@...radead.org>
> ---
......

> -bool
> -xfs_isilocked(
> +void
> +xfs_assert_ilocked(
>  	struct xfs_inode	*ip,
>  	uint			lock_flags)
>  {
> -	if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
> -		if (!(lock_flags & XFS_ILOCK_SHARED))
> -			return !!ip->i_lock.mr_writer;
> -		return rwsem_is_locked(&ip->i_lock.mr_lock);
> -	}
> -
> -	if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
> -		return __xfs_rwsem_islocked(&VFS_I(ip)->i_mapping->invalidate_lock,
> -				(lock_flags & XFS_MMAPLOCK_SHARED));
> -	}
> -
> -	if (lock_flags & (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED)) {
> -		return __xfs_rwsem_islocked(&VFS_I(ip)->i_rwsem,
> -				(lock_flags & XFS_IOLOCK_SHARED));
> -	}
> -
> -	ASSERT(0);
> -	return false;
> +	if (lock_flags & XFS_ILOCK_SHARED)
> +		rwsem_assert_held(&ip->i_lock.mr_lock);
> +	else if (lock_flags & XFS_ILOCK_EXCL)
> +		BUG_ON(!ip->i_lock.mr_writer);

		ASSERT(!ip->i_lock.mr_writer);

Otherwise OK.

-Dave.

-- 
Dave Chinner
david@...morbit.com