[PATCH v6 01/34] vfs: Unconditionally set IOCB_WRITE in call_write_iter()

[David Howells <dhowells@xxxxxxxxxx>]

IOCB_WRITE is set by aio, io_uring and cachefiles before submitting a write
operation to the VFS, but it isn't set by, say, the write() system call.

Fix this by setting IOCB_WRITE unconditionally in call_write_iter().

This will allow drivers to use IOCB_WRITE instead of the iterator data
source to determine the I/O direction.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
cc: Christoph Hellwig <hch@xxxxxx>
cc: Jens Axboe <axboe@xxxxxxxxx>
cc: linux-block@xxxxxxxxxxxxxxx
cc: linux-fsdevel@xxxxxxxxxxxxxxx
---

 include/linux/fs.h |    1 +
 1 file changed, 1 insertion(+)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 066555ad1bf8..649ff061440e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2183,6 +2183,7 @@ static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,
 static inline ssize_t call_write_iter(struct file *file, struct kiocb *kio,
 				      struct iov_iter *iter)
 {
+	kio->ki_flags |= IOCB_WRITE;
 	return file->f_op->write_iter(kio, iter);
 }