diff options
Diffstat (limited to '')
-rw-r--r-- | arch/x86/include/asm/irqflags.h | 142 |
1 files changed, 142 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..7793e52d6 --- /dev/null +++ b/arch/x86/include/asm/irqflags.h @@ -0,0 +1,142 @@ +/* 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; +} + +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_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 + +#ifdef CONFIG_X86_64 +#ifdef CONFIG_DEBUG_ENTRY +#define SAVE_FLAGS pushfq; popq %rax +#endif + +#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); +} + +static __always_inline void arch_local_irq_restore(unsigned long flags) +{ + if (!arch_irqs_disabled_flags(flags)) + arch_local_irq_enable(); +} +#endif /* !__ASSEMBLY__ */ + +#endif |