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Message-ID: <f555b324b79829d6fc63da0d05995ce337969f65.camel@kernel.org>
Subject: Re: [PATCH 17/26] netfs: Fix writethrough-mode error handling
From: Jeff Layton <jlayton@kernel.org>
To: David Howells <dhowells@redhat.com>, Christian Brauner
	 <christian@brauner.io>, Gao Xiang <hsiangkao@linux.alibaba.com>, Dominique
	Martinet <asmadeus@codewreck.org>
Cc: Matthew Wilcox <willy@infradead.org>, Steve French <smfrench@gmail.com>,
  Marc Dionne <marc.dionne@auristor.com>, Paulo Alcantara
 <pc@manguebit.com>, Shyam Prasad N <sprasad@microsoft.com>, Tom Talpey
 <tom@talpey.com>, Eric Van Hensbergen <ericvh@kernel.org>, Ilya Dryomov
 <idryomov@gmail.com>, netfs@lists.linux.dev,  linux-cachefs@redhat.com,
 linux-afs@lists.infradead.org,  linux-cifs@vger.kernel.org,
 linux-nfs@vger.kernel.org,  ceph-devel@vger.kernel.org,
 v9fs@lists.linux.dev, linux-erofs@lists.ozlabs.org, 
 linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, 
 linux-kernel@vger.kernel.org
Date: Mon, 15 Apr 2024 08:40:21 -0400
In-Reply-To: <20240328163424.2781320-18-dhowells@redhat.com>
References: <20240328163424.2781320-1-dhowells@redhat.com>
	 <20240328163424.2781320-18-dhowells@redhat.com>
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On Thu, 2024-03-28 at 16:34 +0000, David Howells wrote:
> Fix the error return in netfs_perform_write() acting in writethrough-mode
> to return any cached error in the case that netfs_end_writethrough()
> returns 0.
>=20
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jeff Layton <jlayton@kernel.org>
> cc: netfs@lists.linux.dev
> cc: linux-fsdevel@vger.kernel.org
> ---
>  fs/netfs/buffered_write.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
>=20
> diff --git a/fs/netfs/buffered_write.c b/fs/netfs/buffered_write.c
> index 8e4a3fb287e3..db4ad158948b 100644
> --- a/fs/netfs/buffered_write.c
> +++ b/fs/netfs/buffered_write.c
> @@ -188,7 +188,7 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struc=
t iov_iter *iter,
>  	enum netfs_how_to_modify howto;
>  	enum netfs_folio_trace trace;
>  	unsigned int bdp_flags =3D (iocb->ki_flags & IOCB_SYNC) ? 0: BDP_ASYNC;
> -	ssize_t written =3D 0, ret;
> +	ssize_t written =3D 0, ret, ret2;
>  	loff_t i_size, pos =3D iocb->ki_pos, from, to;
>  	size_t max_chunk =3D PAGE_SIZE << MAX_PAGECACHE_ORDER;
>  	bool maybe_trouble =3D false;
> @@ -409,10 +409,12 @@ ssize_t netfs_perform_write(struct kiocb *iocb, str=
uct iov_iter *iter,
> =20
>  out:
>  	if (unlikely(wreq)) {
> -		ret =3D netfs_end_writethrough(wreq, iocb);
> +		ret2 =3D netfs_end_writethrough(wreq, iocb);
>  		wbc_detach_inode(&wbc);
> -		if (ret =3D=3D -EIOCBQUEUED)
> -			return ret;
> +		if (ret2 =3D=3D -EIOCBQUEUED)
> +			return ret2;
> +		if (ret =3D=3D 0)
> +			ret =3D ret2;
>  	}
> =20
>  	iocb->ki_pos +=3D written;
>=20

Should this be merged independently? It looks like a bug that's present
now.

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