From 213f627104daf8589aad8ee73fcaeb603ab0af15 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 23 Jan 2021 10:06:10 -0800 Subject: iomap: add a IOMAP_DIO_OVERWRITE_ONLY flag Add a flag to signal that only pure overwrites are allowed. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Reviewed-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/iomap/direct-io.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'fs/iomap') diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 947343730e2c..65d32364345d 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -485,6 +485,13 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, iomap_flags |= IOMAP_NOWAIT; } + if (dio_flags & IOMAP_DIO_OVERWRITE_ONLY) { + ret = -EAGAIN; + if (pos >= dio->i_size || pos + count > dio->i_size) + goto out_free_dio; + iomap_flags |= IOMAP_OVERWRITE_ONLY; + } + ret = filemap_write_and_wait_range(mapping, pos, end); if (ret) goto out_free_dio; -- cgit v1.2.3