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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/x86/include/asm/irqflags.h
parentInitial commit. (diff)
downloadlinux-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.h213
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