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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/x86/include/asm/irqflags.h | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/include/asm/irqflags.h')
-rw-r--r-- | arch/x86/include/asm/irqflags.h | 213 |
1 files changed, 213 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..c99c66b41 --- /dev/null +++ b/arch/x86/include/asm/irqflags.h @@ -0,0 +1,213 @@ +/* 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 __attribute__((__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 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 inline void native_irq_disable(void) +{ + asm volatile("cli": : :"memory"); +} + +static 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 +#include <asm/paravirt.h> +#else +#ifndef __ASSEMBLY__ +#include <linux/types.h> + +static inline notrace unsigned long arch_local_save_flags(void) +{ + return native_save_fl(); +} + +static inline notrace void arch_local_irq_restore(unsigned long flags) +{ + native_restore_fl(flags); +} + +static inline notrace void arch_local_irq_disable(void) +{ + native_irq_disable(); +} + +static inline notrace 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 inline notrace 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 +#define SWAPGS swapgs +/* + * Currently paravirt can't handle swapgs nicely when we + * don't have a stack we can rely on (such as a user space + * stack). So we either find a way around these or just fault + * and emulate if a guest tries to call swapgs directly. + * + * Either way, this is a good way to document that we don't + * have a reliable stack. x86_64 only. + */ +#define SWAPGS_UNSAFE_STACK swapgs + +#define PARAVIRT_ADJUST_EXCEPTION_FRAME /* */ + +#define INTERRUPT_RETURN jmp native_iret +#define USERGS_SYSRET64 \ + swapgs; \ + sysretq; +#define USERGS_SYSRET32 \ + swapgs; \ + sysretl + +#ifdef CONFIG_DEBUG_ENTRY +#define SAVE_FLAGS(x) pushfq; popq %rax +#endif +#else +#define INTERRUPT_RETURN iret +#define ENABLE_INTERRUPTS_SYSEXIT sti; sysexit +#define GET_CR0_INTO_EAX movl %cr0, %eax +#endif + + +#endif /* __ASSEMBLY__ */ +#endif /* CONFIG_PARAVIRT */ + +#ifndef __ASSEMBLY__ +static inline int arch_irqs_disabled_flags(unsigned long flags) +{ + return !(flags & X86_EFLAGS_IF); +} + +static inline int arch_irqs_disabled(void) +{ + unsigned long flags = arch_local_save_flags(); + + return arch_irqs_disabled_flags(flags); +} +#endif /* !__ASSEMBLY__ */ + +#ifdef __ASSEMBLY__ +#ifdef CONFIG_TRACE_IRQFLAGS +# define TRACE_IRQS_ON call trace_hardirqs_on_thunk; +# define TRACE_IRQS_OFF call trace_hardirqs_off_thunk; +#else +# define TRACE_IRQS_ON +# define TRACE_IRQS_OFF +#endif +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# ifdef CONFIG_X86_64 +# define LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk +# define LOCKDEP_SYS_EXIT_IRQ \ + TRACE_IRQS_ON; \ + sti; \ + call lockdep_sys_exit_thunk; \ + cli; \ + TRACE_IRQS_OFF; +# else +# define LOCKDEP_SYS_EXIT \ + pushl %eax; \ + pushl %ecx; \ + pushl %edx; \ + call lockdep_sys_exit; \ + popl %edx; \ + popl %ecx; \ + popl %eax; +# define LOCKDEP_SYS_EXIT_IRQ +# endif +#else +# define LOCKDEP_SYS_EXIT +# define LOCKDEP_SYS_EXIT_IRQ +#endif +#endif /* __ASSEMBLY__ */ + +#endif |