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From:   Andreas Gruenbacher <agruenba@redhat.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>,
        "Darrick J. Wong" <djwong@kernel.org>
Cc:     Jan Kara <jack@suse.cz>, Matthew Wilcox <willy@infradead.org>,
        cluster-devel@redhat.com, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, ocfs2-devel@oss.oracle.com,
        Andreas Gruenbacher <agruenba@redhat.com>
Subject: [PATCH v7 14/19] iomap: Fix iomap_dio_rw return value for user copies
Date:   Fri, 27 Aug 2021 18:49:21 +0200
Message-Id: <20210827164926.1726765-15-agruenba@redhat.com>
In-Reply-To: <20210827164926.1726765-1-agruenba@redhat.com>
References: <20210827164926.1726765-1-agruenba@redhat.com>
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When a user copy fails in one of the helpers of iomap_dio_rw, fail with
-EFAULT instead of returning 0.  This matches what iomap_dio_bio_actor
returns when it gets an -EFAULT from bio_iov_iter_get_pages.  With these
changes, iomap_dio_actor now consistently fails with -EFAULT when a user
page cannot be faulted in.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
---
 fs/iomap/direct-io.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 9398b8c31323..8054f5d6c273 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -370,7 +370,7 @@ iomap_dio_hole_actor(loff_t length, struct iomap_dio *dio)
 {
 	length = iov_iter_zero(length, dio->submit.iter);
 	dio->size += length;
-	return length;
+	return length ? length : -EFAULT;
 }
 
 static loff_t
@@ -397,7 +397,7 @@ iomap_dio_inline_actor(struct inode *inode, loff_t pos, loff_t length,
 		copied = copy_to_iter(iomap->inline_data + pos, length, iter);
 	}
 	dio->size += copied;
-	return copied;
+	return copied ? copied : -EFAULT;
 }
 
 static loff_t
-- 
2.26.3