From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Tue, 11 Aug 2020 15:05:06 +0000 (+0100)
Subject: x86/asm: Split __wr{fs,gs}base() out of write_{fs,gs}_base()
X-Git-Tag: archive/raspbian/4.16.0+51-g0941d6cb-1+rpi1~2^2~42^2~1583
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=ecc9553a12cb14537c851bca43a9f55f23eb6bf0;p=xen.git

x86/asm: Split __wr{fs,gs}base() out of write_{fs,gs}_base()

To match the read side which is already split out.  A future change will want
to use them.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
---

diff --git a/xen/include/asm-x86/msr.h b/xen/include/asm-x86/msr.h
index 5e141ac5a5..16f95e7344 100644
--- a/xen/include/asm-x86/msr.h
+++ b/xen/include/asm-x86/msr.h
@@ -156,6 +156,24 @@ static inline unsigned long __rdgsbase(void)
     return base;
 }
 
+static inline void __wrfsbase(unsigned long base)
+{
+#ifdef HAVE_AS_FSGSBASE
+    asm volatile ( "wrfsbase %0" :: "r" (base) );
+#else
+    asm volatile ( ".byte 0xf3, 0x48, 0x0f, 0xae, 0xd0" :: "a" (base) );
+#endif
+}
+
+static inline void __wrgsbase(unsigned long base)
+{
+#ifdef HAVE_AS_FSGSBASE
+    asm volatile ( "wrgsbase %0" :: "r" (base) );
+#else
+    asm volatile ( ".byte 0xf3, 0x48, 0x0f, 0xae, 0xd8" :: "a" (base) );
+#endif
+}
+
 static inline unsigned long read_fs_base(void)
 {
     unsigned long base;
@@ -199,11 +217,7 @@ static inline unsigned long read_gs_shadow(void)
 static inline void write_fs_base(unsigned long base)
 {
     if ( read_cr4() & X86_CR4_FSGSBASE )
-#ifdef HAVE_AS_FSGSBASE
-        asm volatile ( "wrfsbase %0" :: "r" (base) );
-#else
-        asm volatile ( ".byte 0xf3, 0x48, 0x0f, 0xae, 0xd0" :: "a" (base) );
-#endif
+        __wrfsbase(base);
     else
         wrmsrl(MSR_FS_BASE, base);
 }
@@ -211,11 +225,7 @@ static inline void write_fs_base(unsigned long base)
 static inline void write_gs_base(unsigned long base)
 {
     if ( read_cr4() & X86_CR4_FSGSBASE )
-#ifdef HAVE_AS_FSGSBASE
-        asm volatile ( "wrgsbase %0" :: "r" (base) );
-#else
-        asm volatile ( ".byte 0xf3, 0x48, 0x0f, 0xae, 0xd8" :: "a" (base) );
-#endif
+        __wrgsbase(base);
     else
         wrmsrl(MSR_GS_BASE, base);
 }