Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Andreas Gruenbacher <agruenba@redhat.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.15 121/177] gfs2: Make sure not to return short direct writes
Date:   Wed,  4 May 2022 18:45:14 +0200
Message-Id: <20220504153103.971992183@linuxfoundation.org>
In-Reply-To: <20220504153053.873100034@linuxfoundation.org>
References: <20220504153053.873100034@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Andreas Gruenbacher <agruenba@redhat.com>

[ Upstream commit 3bde4c48586074202044456285a97ccdf9048988 ]

When direct writes fail with -ENOTBLK because we're writing into a
hole (gfs2_iomap_begin()) or because of a page invalidation failure
(iomap_dio_rw()), we're falling back to buffered writes.  In that case,
when we lose the inode glock in gfs2_file_buffered_write(), we want to
re-acquire it instead of returning a short write.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/gfs2/file.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 964c19e27ce2..42fa4b5b81a0 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -1076,7 +1076,7 @@ static ssize_t gfs2_file_buffered_write(struct kiocb *iocb,
 			from->count = min(from->count, window_size - leftover);
 			if (gfs2_holder_queued(gh))
 				goto retry_under_glock;
-			if (read)
+			if (read && !(iocb->ki_flags & IOCB_DIRECT))
 				goto out_uninit;
 			goto retry;
 		}
-- 
2.35.1