lkml.org 
[lkml]   [2021]   [Feb]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC v1 07/26] x86/tdx: Wire up KVM hypercalls
Date
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>

KVM hypercalls have to be wrapped into vendor-specific TDVMCALLs.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
---
arch/x86/include/asm/kvm_para.h | 21 ++++++
arch/x86/include/asm/tdx.h | 8 +++
arch/x86/kernel/tdx-kvm.c | 116 ++++++++++++++++++++++++++++++++
arch/x86/kernel/tdx.c | 4 ++
4 files changed, 149 insertions(+)
create mode 100644 arch/x86/kernel/tdx-kvm.c

diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h
index 338119852512..2fa85481520b 100644
--- a/arch/x86/include/asm/kvm_para.h
+++ b/arch/x86/include/asm/kvm_para.h
@@ -6,6 +6,7 @@
#include <asm/alternative.h>
#include <linux/interrupt.h>
#include <uapi/asm/kvm_para.h>
+#include <asm/tdx.h>

extern void kvmclock_init(void);

@@ -34,6 +35,10 @@ static inline bool kvm_check_and_clear_guest_paused(void)
static inline long kvm_hypercall0(unsigned int nr)
{
long ret;
+
+ if (is_tdx_guest())
+ return tdx_kvm_hypercall0(nr);
+
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr)
@@ -44,6 +49,10 @@ static inline long kvm_hypercall0(unsigned int nr)
static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
{
long ret;
+
+ if (is_tdx_guest())
+ return tdx_kvm_hypercall1(nr, p1);
+
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1)
@@ -55,6 +64,10 @@ static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
unsigned long p2)
{
long ret;
+
+ if (is_tdx_guest())
+ return tdx_kvm_hypercall2(nr, p1, p2);
+
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2)
@@ -66,6 +79,10 @@ static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
unsigned long p2, unsigned long p3)
{
long ret;
+
+ if (is_tdx_guest())
+ return tdx_kvm_hypercall3(nr, p1, p2, p3);
+
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2), "d"(p3)
@@ -78,6 +95,10 @@ static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
unsigned long p4)
{
long ret;
+
+ if (is_tdx_guest())
+ return tdx_kvm_hypercall4(nr, p1, p2, p3, p4);
+
asm volatile(KVM_HYPERCALL
: "=a"(ret)
: "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index b98de067257b..8c3e5af88643 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -51,4 +51,12 @@ unsigned long tdx_get_ve_info(struct ve_info *ve);
int tdx_handle_virtualization_exception(struct pt_regs *regs,
struct ve_info *ve);

+long tdx_kvm_hypercall0(unsigned int nr);
+long tdx_kvm_hypercall1(unsigned int nr, unsigned long p1);
+long tdx_kvm_hypercall2(unsigned int nr, unsigned long p1, unsigned long p2);
+long tdx_kvm_hypercall3(unsigned int nr, unsigned long p1, unsigned long p2,
+ unsigned long p3);
+long tdx_kvm_hypercall4(unsigned int nr, unsigned long p1, unsigned long p2,
+ unsigned long p3, unsigned long p4);
+
#endif /* _ASM_X86_TDX_H */
diff --git a/arch/x86/kernel/tdx-kvm.c b/arch/x86/kernel/tdx-kvm.c
new file mode 100644
index 000000000000..323d43fcb338
--- /dev/null
+++ b/arch/x86/kernel/tdx-kvm.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+long tdx_kvm_hypercall0(unsigned int nr)
+{
+ register long r10 asm("r10") = TDVMCALL_VENDOR;
+ register long r11 asm("r11") = nr;
+ register long rcx asm("rcx");
+ long ret;
+
+ /* Allow to pass R10 and R11 down to the VMM */
+ rcx = BIT(10) | BIT(11);
+
+ asm volatile(TDCALL
+ : "=a"(ret), "=r"(r10)
+ : "a"(TDVMCALL), "r"(rcx), "r"(r10), "r"(r11)
+ : "memory");
+
+ BUG_ON(ret);
+ return r10;
+}
+EXPORT_SYMBOL_GPL(tdx_kvm_hypercall0);
+
+long tdx_kvm_hypercall1(unsigned int nr, unsigned long p1)
+{
+ register long r10 asm("r10") = TDVMCALL_VENDOR;
+ register long r11 asm("r11") = nr;
+ register long r12 asm("r12") = p1;
+ register long rcx asm("rcx");
+ long ret;
+
+ /* Allow to pass R10, R11 and R12 down to the VMM */
+ rcx = BIT(10) | BIT(11) | BIT(12);
+
+ asm volatile(TDCALL
+ : "=a"(ret), "=r"(r10)
+ : "a"(TDVMCALL), "r"(rcx), "r"(r10), "r"(r11), "r"(r12)
+ : "memory");
+
+ BUG_ON(ret);
+ return r10;
+}
+EXPORT_SYMBOL_GPL(tdx_kvm_hypercall1);
+
+long tdx_kvm_hypercall2(unsigned int nr, unsigned long p1, unsigned long p2)
+{
+ register long r10 asm("r10") = TDVMCALL_VENDOR;
+ register long r11 asm("r11") = nr;
+ register long r12 asm("r12") = p1;
+ register long r13 asm("r13") = p2;
+ register long rcx asm("rcx");
+ long ret;
+
+ /* Allow to pass R10, R11, R12 and R13 down to the VMM */
+ rcx = BIT(10) | BIT(11) | BIT(12) | BIT(13);
+
+ asm volatile(TDCALL
+ : "=a"(ret), "=r"(r10)
+ : "a"(TDVMCALL), "r"(rcx), "r"(r10), "r"(r11), "r"(r12),
+ "r"(r13)
+ : "memory");
+
+ BUG_ON(ret);
+ return r10;
+}
+EXPORT_SYMBOL_GPL(tdx_kvm_hypercall2);
+
+long tdx_kvm_hypercall3(unsigned int nr, unsigned long p1, unsigned long p2,
+ unsigned long p3)
+{
+ register long r10 asm("r10") = TDVMCALL_VENDOR;
+ register long r11 asm("r11") = nr;
+ register long r12 asm("r12") = p1;
+ register long r13 asm("r13") = p2;
+ register long r14 asm("r14") = p3;
+ register long rcx asm("rcx");
+ long ret;
+
+ /* Allow to pass R10, R11, R12, R13 and R14 down to the VMM */
+ rcx = BIT(10) | BIT(11) | BIT(12) | BIT(13) | BIT(14);
+
+ asm volatile(TDCALL
+ : "=a"(ret), "=r"(r10)
+ : "a"(TDVMCALL), "r"(rcx), "r"(r10), "r"(r11), "r"(r12),
+ "r"(r13), "r"(r14)
+ : "memory");
+
+ BUG_ON(ret);
+ return r10;
+}
+EXPORT_SYMBOL_GPL(tdx_kvm_hypercall3);
+
+long tdx_kvm_hypercall4(unsigned int nr, unsigned long p1, unsigned long p2,
+ unsigned long p3, unsigned long p4)
+{
+ register long r10 asm("r10") = TDVMCALL_VENDOR;
+ register long r11 asm("r11") = nr;
+ register long r12 asm("r12") = p1;
+ register long r13 asm("r13") = p2;
+ register long r14 asm("r14") = p3;
+ register long r15 asm("r15") = p4;
+ register long rcx asm("rcx");
+ long ret;
+
+ /* Allow to pass R10, R11, R12, R13, R14 and R15 down to the VMM */
+ rcx = BIT(10) | BIT(11) | BIT(12) | BIT(13) | BIT(14) | BIT(15);
+
+ asm volatile(TDCALL
+ : "=a"(ret), "=r"(r10)
+ : "a"(TDVMCALL), "r"(rcx), "r"(r10), "r"(r11), "r"(r12),
+ "r"(r13), "r"(r14), "r"(r15)
+ : "memory");
+
+ BUG_ON(ret);
+ return r10;
+}
+EXPORT_SYMBOL_GPL(tdx_kvm_hypercall4);
diff --git a/arch/x86/kernel/tdx.c b/arch/x86/kernel/tdx.c
index 25dd33bc2e49..bbefe639a2ed 100644
--- a/arch/x86/kernel/tdx.c
+++ b/arch/x86/kernel/tdx.c
@@ -7,6 +7,10 @@
#include <asm/tdx.h>
#include <asm/vmx.h>

+#ifdef CONFIG_KVM_GUEST
+#include "tdx-kvm.c"
+#endif
+
static struct {
unsigned int gpa_width;
unsigned long attributes;
--
2.25.1
\
 
 \ /
  Last update: 2021-02-06 05:44    [W:0.611 / U:1.204 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site