Re: [PATCH 3/6] Input: Update vmmouse.c to use the common VMW_PORT macros

From: Sinclair Yeh
Date: Tue Dec 01 2015 - 17:31:39 EST


Hi,

On Tue, Dec 01, 2015 at 02:24:14PM -0800, Dmitry Torokhov wrote:
> On Tue, Dec 01, 2015 at 02:18:49PM -0800, Sinclair Yeh wrote:
> > v2:
> > Instead of replacing existing VMMOUSE defines, only modify enough
> > to use the new VMW_PORT define.
> >
> > v3:
> > Use updated VMWARE_PORT() which requires hypervisor magic as an added
> > parameter
> >
> > Signed-off-by: Sinclair Yeh <syeh@xxxxxxxxxx>
> > Reviewed-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
> > Reviewed-by: Alok N Kataria <akataria@xxxxxxxxxx>
> > Cc: pv-drivers@xxxxxxxxxx
> > Cc: linux-graphics-maintainer@xxxxxxxxxx
> > Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> > Cc: Arnd Bergmann <arnd@xxxxxxxx>
> > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> > Cc: linux-kernel@xxxxxxxxxxxxxxx
> > Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
> > Cc: linux-input@xxxxxxxxxxxxxxx
> > ---
> > drivers/input/mouse/vmmouse.c | 22 +++++++---------------
> > 1 file changed, 7 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/input/mouse/vmmouse.c b/drivers/input/mouse/vmmouse.c
> > index e272f06..d34e3e4 100644
> > --- a/drivers/input/mouse/vmmouse.c
> > +++ b/drivers/input/mouse/vmmouse.c
> > @@ -19,6 +19,7 @@
> > #include <linux/slab.h>
> > #include <linux/module.h>
> > #include <asm/hypervisor.h>
> > +#include <asm/vmware.h>
> >
> > #include "psmouse.h"
> > #include "vmmouse.h"
> > @@ -84,21 +85,12 @@ struct vmmouse_data {
> > * implementing the vmmouse protocol. Should never execute on
> > * bare metal hardware.
> > */
> > -#define VMMOUSE_CMD(cmd, in1, out1, out2, out3, out4) \
> > -({ \
> > - unsigned long __dummy1, __dummy2; \
> > - __asm__ __volatile__ ("inl %%dx" : \
> > - "=a"(out1), \
> > - "=b"(out2), \
> > - "=c"(out3), \
> > - "=d"(out4), \
> > - "=S"(__dummy1), \
> > - "=D"(__dummy2) : \
> > - "a"(VMMOUSE_PROTO_MAGIC), \
> > - "b"(in1), \
> > - "c"(VMMOUSE_PROTO_CMD_##cmd), \
> > - "d"(VMMOUSE_PROTO_PORT) : \
> > - "memory"); \
> > +#define VMMOUSE_CMD(cmd, in1, out1, out2, out3, out4) \
> > +({ \
> > + unsigned long __dummy1 = 0, __dummy2 = 0; \
>
> Why do we need to initialize dummies?

Because for some commands those parameters to VMW_PORT() can be both
input and outout. So it's safer to initialize them to 0. Since
they can potentially be an output, we can't make them a constant.

>
> > + VMW_PORT(in1, VMMOUSE_PROTO_CMD_##cmd, VMMOUSE_PROTO_PORT, \
> > + VMMOUSE_PROTO_MAGIC, \
> > + out1, out2, out3, out4, __dummy1, __dummy2); \
> > })
> >
>
> Thanks.
>
> --
> Dmitry
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/