linux/arch/x86/include/asm/vmware.h
Thomas Hellstrom b4dd4f6e36 x86/vmware: Add a header file for hypercall definitions
The new header is intended to be used by drivers using the backdoor.
Follow the KVM example using alternatives self-patching to choose
between vmcall, vmmcall and io instructions.

Also define two new CPU feature flags to indicate hypervisor support
for vmcall- and vmmcall instructions. The new XF86_FEATURE_VMW_VMMCALL
flag is needed because using XF86_FEATURE_VMMCALL might break QEMU/KVM
setups using the vmmouse driver. They rely on XF86_FEATURE_VMMCALL
on AMD to get the kvm_hypercall() right. But they do not yet implement
vmmcall for the VMware hypercall used by the vmmouse driver.

 [ bp: reflow hypercall %edx usage explanation comment. ]

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Doug Covelli <dcovelli@vmware.com>
Cc: Aaron Lewis <aaronlewis@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: linux-graphics-maintainer@vmware.com
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Robert Hoo <robert.hu@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: <pv-drivers@vmware.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190828080353.12658-3-thomas_os@shipmail.org
2019-08-28 13:32:06 +02:00

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1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 or MIT */
#ifndef _ASM_X86_VMWARE_H
#define _ASM_X86_VMWARE_H
#include <asm/cpufeatures.h>
#include <asm/alternative.h>
/*
* The hypercall definitions differ in the low word of the %edx argument
* in the following way: the old port base interface uses the port
* number to distinguish between high- and low bandwidth versions.
*
* The new vmcall interface instead uses a set of flags to select
* bandwidth mode and transfer direction. The flags should be loaded
* into %dx by any user and are automatically replaced by the port
* number if the VMWARE_HYPERVISOR_PORT method is used.
*
* In short, new driver code should strictly use the new definition of
* %dx content.
*/
/* Old port-based version */
#define VMWARE_HYPERVISOR_PORT "0x5658"
#define VMWARE_HYPERVISOR_PORT_HB "0x5659"
/* Current vmcall / vmmcall version */
#define VMWARE_HYPERVISOR_HB BIT(0)
#define VMWARE_HYPERVISOR_OUT BIT(1)
/* The low bandwidth call. The low word of edx is presumed clear. */
#define VMWARE_HYPERCALL \
ALTERNATIVE_2("movw $" VMWARE_HYPERVISOR_PORT ", %%dx; inl (%%dx)", \
"vmcall", X86_FEATURE_VMCALL, \
"vmmcall", X86_FEATURE_VMW_VMMCALL)
/*
* The high bandwidth out call. The low word of edx is presumed to have the
* HB and OUT bits set.
*/
#define VMWARE_HYPERCALL_HB_OUT \
ALTERNATIVE_2("movw $" VMWARE_HYPERVISOR_PORT_HB ", %%dx; rep outsb", \
"vmcall", X86_FEATURE_VMCALL, \
"vmmcall", X86_FEATURE_VMW_VMMCALL)
/*
* The high bandwidth in call. The low word of edx is presumed to have the
* HB bit set.
*/
#define VMWARE_HYPERCALL_HB_IN \
ALTERNATIVE_2("movw $" VMWARE_HYPERVISOR_PORT_HB ", %%dx; rep insb", \
"vmcall", X86_FEATURE_VMCALL, \
"vmmcall", X86_FEATURE_VMW_VMMCALL)
#endif