[PATCH v5 4/5] x86/gsseg: move load_gs_index() to its own new header file

From: Xin Li
Date: Mon Nov 28 2022 - 12:05:22 EST


From: "H. Peter Anvin (Intel)" <hpa@xxxxxxxxx>

GS is a special segment on x86_64, move load_gs_index() to its own new
header file.

Signed-off-by: H. Peter Anvin (Intel) <hpa@xxxxxxxxx>
Signed-off-by: Xin Li <xin3.li@xxxxxxxxx>
---
arch/x86/ia32/ia32_signal.c | 1 +
arch/x86/include/asm/gsseg.h | 41 ++++++++++++++++++++++++++++
arch/x86/include/asm/mmu_context.h | 1 +
arch/x86/include/asm/special_insns.h | 21 --------------
arch/x86/kernel/paravirt.c | 1 +
arch/x86/kernel/tls.c | 1 +
6 files changed, 45 insertions(+), 21 deletions(-)
create mode 100644 arch/x86/include/asm/gsseg.h

diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index c9c3859322fa..14c739303099 100644
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -34,6 +34,7 @@
#include <asm/sigframe.h>
#include <asm/sighandling.h>
#include <asm/smap.h>
+#include <asm/gsseg.h>

static inline void reload_segments(struct sigcontext_32 *sc)
{
diff --git a/arch/x86/include/asm/gsseg.h b/arch/x86/include/asm/gsseg.h
new file mode 100644
index 000000000000..d15577c39e8d
--- /dev/null
+++ b/arch/x86/include/asm/gsseg.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _ASM_X86_GSSEG_H
+#define _ASM_X86_GSSEG_H
+
+#include <linux/types.h>
+
+#include <asm/asm.h>
+#include <asm/cpufeature.h>
+#include <asm/alternative.h>
+#include <asm/processor.h>
+#include <asm/nops.h>
+
+#ifdef CONFIG_X86_64
+
+extern asmlinkage void asm_load_gs_index(u16 selector);
+
+static inline void native_load_gs_index(unsigned int selector)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ asm_load_gs_index(selector);
+ local_irq_restore(flags);
+}
+
+#endif /* CONFIG_X86_64 */
+
+#ifndef CONFIG_PARAVIRT_XXL
+
+static inline void load_gs_index(unsigned int selector)
+{
+#ifdef CONFIG_X86_64
+ native_load_gs_index(selector);
+#else
+ loadsegment(gs, selector);
+#endif
+}
+
+#endif /* CONFIG_PARAVIRT_XXL */
+
+#endif /* _ASM_X86_GSSEG_H */
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index b8d40ddeab00..e01aa74a6de7 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -12,6 +12,7 @@
#include <asm/tlbflush.h>
#include <asm/paravirt.h>
#include <asm/debugreg.h>
+#include <asm/gsseg.h>

extern atomic64_t last_mm_ctx_id;

diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h
index a71d0e8d4684..cfd9499b617c 100644
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -120,17 +120,6 @@ static inline void native_wbinvd(void)
asm volatile("wbinvd": : :"memory");
}

-extern asmlinkage void asm_load_gs_index(u16 selector);
-
-static inline void native_load_gs_index(unsigned int selector)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- asm_load_gs_index(selector);
- local_irq_restore(flags);
-}
-
static inline unsigned long __read_cr4(void)
{
return native_read_cr4();
@@ -184,16 +173,6 @@ static inline void wbinvd(void)
native_wbinvd();
}

-
-static inline void load_gs_index(unsigned int selector)
-{
-#ifdef CONFIG_X86_64
- native_load_gs_index(selector);
-#else
- loadsegment(gs, selector);
-#endif
-}
-
#endif /* CONFIG_PARAVIRT_XXL */

static inline void clflush(volatile void *__p)
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 7ca2d46c08cc..00f6a92551d2 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -32,6 +32,7 @@
#include <asm/special_insns.h>
#include <asm/tlb.h>
#include <asm/io_bitmap.h>
+#include <asm/gsseg.h>

/*
* nop stub, which must not clobber anything *including the stack* to
diff --git a/arch/x86/kernel/tls.c b/arch/x86/kernel/tls.c
index 3c883e064242..3ffbab0081f4 100644
--- a/arch/x86/kernel/tls.c
+++ b/arch/x86/kernel/tls.c
@@ -12,6 +12,7 @@
#include <asm/ldt.h>
#include <asm/processor.h>
#include <asm/proto.h>
+#include <asm/gsseg.h>

#include "tls.h"

--
2.34.1