x86, um: ... and asm-x86 move

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 211 insertions, 0 deletions

diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
new file mode 100644
index 0000000..2bdab21
--- /dev/null
+++ b/arch/x86/include/asm/irqflags.h
@@ -0,0 +1,211 @@
+#ifndef _X86_IRQFLAGS_H_
+#define _X86_IRQFLAGS_H_
+
+#include <asm/processor-flags.h>
+
+#ifndef __ASSEMBLY__
+/*
+ * Interrupt control:
+ */
+
+static inline unsigned long native_save_fl(void)
+{
+	unsigned long flags;
+
+	asm volatile("# __raw_save_flags\n\t"
+		     "pushf ; pop %0"
+		     : "=g" (flags)
+		     : /* no input */
+		     : "memory");
+
+	return flags;
+}
+
+static 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 void native_safe_halt(void)
+{
+	asm volatile("sti; hlt": : :"memory");
+}
+
+static inline void native_halt(void)
+{
+	asm volatile("hlt": : :"memory");
+}
+
+#endif
+
+#ifdef CONFIG_PARAVIRT
+#include <asm/paravirt.h>
+#else
+#ifndef __ASSEMBLY__
+
+static inline unsigned long __raw_local_save_flags(void)
+{
+	return native_save_fl();
+}
+
+static inline void raw_local_irq_restore(unsigned long flags)
+{
+	native_restore_fl(flags);
+}
+
+static inline void raw_local_irq_disable(void)
+{
+	native_irq_disable();
+}
+
+static inline void raw_local_irq_enable(void)
+{
+	native_irq_enable();
+}
+
+/*
+ * Used in the idle loop; sti takes one instruction cycle
+ * to complete:
+ */
+static inline void raw_safe_halt(void)
+{
+	native_safe_halt();
+}
+
+/*
+ * Used when interrupts are already enabled or to
+ * shutdown the processor:
+ */
+static inline void halt(void)
+{
+	native_halt();
+}
+
+/*
+ * For spinlocks, etc:
+ */
+static inline unsigned long __raw_local_irq_save(void)
+{
+	unsigned long flags = __raw_local_save_flags();
+
+	raw_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	iretq
+#define USERGS_SYSRET64				\
+	swapgs;					\
+	sysretq;
+#define USERGS_SYSRET32				\
+	swapgs;					\
+	sysretl
+#define ENABLE_INTERRUPTS_SYSEXIT32		\
+	swapgs;					\
+	sti;					\
+	sysexit
+
+#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__
+#define raw_local_save_flags(flags)				\
+	do { (flags) = __raw_local_save_flags(); } while (0)
+
+#define raw_local_irq_save(flags)				\
+	do { (flags) = __raw_local_irq_save(); } while (0)
+
+static inline int raw_irqs_disabled_flags(unsigned long flags)
+{
+	return !(flags & X86_EFLAGS_IF);
+}
+
+static inline int raw_irqs_disabled(void)
+{
+	unsigned long flags = __raw_local_save_flags();
+
+	return raw_irqs_disabled_flags(flags);
+}
+
+#else
+
+#ifdef CONFIG_X86_64
+#define ARCH_LOCKDEP_SYS_EXIT		call lockdep_sys_exit_thunk
+#define ARCH_LOCKDEP_SYS_EXIT_IRQ	\
+	TRACE_IRQS_ON; \
+	sti; \
+	SAVE_REST; \
+	LOCKDEP_SYS_EXIT; \
+	RESTORE_REST; \
+	cli; \
+	TRACE_IRQS_OFF;
+
+#else
+#define ARCH_LOCKDEP_SYS_EXIT			\
+	pushl %eax;				\
+	pushl %ecx;				\
+	pushl %edx;				\
+	call lockdep_sys_exit;			\
+	popl %edx;				\
+	popl %ecx;				\
+	popl %eax;
+
+#define ARCH_LOCKDEP_SYS_EXIT_IRQ
+#endif
+
+#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
+#  define LOCKDEP_SYS_EXIT	ARCH_LOCKDEP_SYS_EXIT
+#  define LOCKDEP_SYS_EXIT_IRQ	ARCH_LOCKDEP_SYS_EXIT_IRQ
+# else
+#  define LOCKDEP_SYS_EXIT
+#  define LOCKDEP_SYS_EXIT_IRQ
+# endif
+
+#endif /* __ASSEMBLY__ */
+#endif