On Tue, Dec 1, 2015 at 2:32 PM, Sinclair Yeh [off-list ref] wrote:

Hi,

On Tue, Dec 01, 2015 at 02:24:14PM -0800, Dmitry Torokhov wrote:

quoted

On Tue, Dec 01, 2015 at 02:18:49PM -0800, Sinclair Yeh wrote:

quoted

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 <redacted>
Reviewed-by: Thomas Hellstrom <redacted>
Reviewed-by: Alok N Kataria <redacted>
Cc: pv-drivers@vmware.com
Cc: linux-graphics-maintainer@vmware.com
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: linux-input@vger.kernel.org
---
 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.

The vmmouse commands do not use them as input though, so it seems we
are simply wasting CPU cycles setting them to 0 just because we are
using the new VMW_PORT here. Why do we need to switch? What is the
benefit of doing this?

Thanks.

-- 
Dmitry