iov_iter: Separate type from direction and use accessor functions

In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index a1c1b7e8a45c..c822e626761b 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -622,7 +622,7 @@ static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
 
 	memset(&msg, 0, sizeof(msg));
 
-	iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
+	iov_iter_kvec(&msg.msg_iter, WRITE, iv, 2, 1 + len);
 
 	l2cap_chan_send(chan, &msg, 1 + len);