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>
diff --git a/drivers/usb/usbip/usbip_common.c b/drivers/usb/usbip/usbip_common.c
index 9756752..45da3e0 100644
--- a/drivers/usb/usbip/usbip_common.c
+++ b/drivers/usb/usbip/usbip_common.c
@@ -309,7 +309,7 @@ int usbip_recv(struct socket *sock, void *buf, int size)
if (!sock || !buf || !size)
return -EINVAL;
- iov_iter_kvec(&msg.msg_iter, READ|ITER_KVEC, &iov, 1, size);
+ iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, size);
usbip_dbg_xmit("enter\n");