1 files changed, 171 insertions, 0 deletions
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
new file mode 100644
index 000000000..8c86edefa
--- /dev/null
+++ b/arch/x86/include/asm/irqflags.h
@@ -0,0 +1,171 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _X86_IRQFLAGS_H_
+#define _X86_IRQFLAGS_H_
+
+#include <asm/processor-flags.h>
+
+#ifndef __ASSEMBLY__
+
+#include <asm/nospec-branch.h>
+
+/* Provide __cpuidle; we can't safely include <linux/cpu.h> */
+#define __cpuidle __section(".cpuidle.text")
+
+/*
+ * Interrupt control:
+ */
+
+/* Declaration required for gcc < 4.9 to prevent -Werror=missing-prototypes */
+extern inline unsigned long native_save_fl(void);
+extern __always_inline unsigned long native_save_fl(void)
+{
+	unsigned long flags;
+
+	/*
+	 * "=rm" is safe here, because "pop" adjusts the stack before
+	 * it evaluates its effective address -- this is part of the
+	 * documented behavior of the "pop" instruction.
+	 */
+	asm volatile("# __raw_save_flags\n\t"
+		     "pushf ; pop %0"
+		     : "=rm" (flags)
+		     : /* no input */
+		     : "memory");
+
+	return flags;
+}
+
+extern inline void native_restore_fl(unsigned long flags);
+extern inline void native_restore_fl(unsigned long flags)
+{
+	asm volatile("push %0 ; popf"
+		     : /* no output */
+		     :"g" (flags)
+		     :"memory", "cc");
+}
+
+static __always_inline void native_irq_disable(void)
+{
+	asm volatile("cli": : :"memory");
+}
+
+static __always_inline void native_irq_enable(void)
+{
+	asm volatile("sti": : :"memory");
+}
+
+static inline __cpuidle void native_safe_halt(void)
+{
+	mds_idle_clear_cpu_buffers();
+	asm volatile("sti; hlt": : :"memory");
+}
+
+static inline __cpuidle void native_halt(void)
+{
+	mds_idle_clear_cpu_buffers();
+	asm volatile("hlt": : :"memory");
+}
+
+#endif
+
+#ifdef CONFIG_PARAVIRT_XXL
+#include <asm/paravirt.h>
+#else
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+
+static __always_inline unsigned long arch_local_save_flags(void)
+{
+	return native_save_fl();
+}
+
+static __always_inline void arch_local_irq_restore(unsigned long flags)
+{
+	native_restore_fl(flags);
+}
+
+static __always_inline void arch_local_irq_disable(void)
+{
+	native_irq_disable();
+}
+
+static __always_inline void arch_local_irq_enable(void)
+{
+	native_irq_enable();
+}
+
+/*
+ * Used in the idle loop; sti takes one instruction cycle
+ * to complete:
+ */
+static inline __cpuidle void arch_safe_halt(void)
+{
+	native_safe_halt();
+}
+
+/*
+ * Used when interrupts are already enabled or to
+ * shutdown the processor:
+ */
+static inline __cpuidle void halt(void)
+{
+	native_halt();
+}
+
+/*
+ * For spinlocks, etc:
+ */
+static __always_inline unsigned long arch_local_irq_save(void)
+{
+	unsigned long flags = arch_local_save_flags();
+	arch_local_irq_disable();
+	return flags;
+}
+#else
+
+#define ENABLE_INTERRUPTS(x)	sti
+#define DISABLE_INTERRUPTS(x)	cli
+
+#ifdef CONFIG_X86_64
+#ifdef CONFIG_DEBUG_ENTRY
+#define SAVE_FLAGS(x)		pushfq; popq %rax
+#endif
+
+#define INTERRUPT_RETURN	jmp native_iret
+#define USERGS_SYSRET64				\
+	swapgs;					\
+	sysretq;
+#define USERGS_SYSRET32				\
+	swapgs;					\
+	sysretl
+
+#else
+#define INTERRUPT_RETURN		iret
+#endif
+
+#endif /* __ASSEMBLY__ */
+#endif /* CONFIG_PARAVIRT_XXL */
+
+#ifndef __ASSEMBLY__
+static __always_inline int arch_irqs_disabled_flags(unsigned long flags)
+{
+	return !(flags & X86_EFLAGS_IF);
+}
+
+static __always_inline int arch_irqs_disabled(void)
+{
+	unsigned long flags = arch_local_save_flags();
+
+	return arch_irqs_disabled_flags(flags);
+}
+#else
+#ifdef CONFIG_X86_64
+#ifdef CONFIG_XEN_PV
+#define SWAPGS	ALTERNATIVE "swapgs", "", X86_FEATURE_XENPV
+#else
+#define SWAPGS	swapgs
+#endif
+#endif
+#endif /* !__ASSEMBLY__ */
+
+#endif