[PATCH Dovetail v2 2/6] arm: irq_pipeline: Move fault_entry() fault_exit() into separate header

Introducing a new header allows us to keep the implementation as
static inline function. Moving them into asm/dovetail.h or
asm/irq_pipeline.h would require us to rewrite those helpers as macros.

Signed-off-by: Florian Bezdeka <[email protected]>
---
 arch/arm/include/asm/trap_entry.h | 82 +++++++++++++++++++++++++++++++++++++++
 arch/arm/mm/fault.c               | 65 +------------------------------
 2 files changed, 83 insertions(+), 64 deletions(-)

diff --git a/arch/arm/include/asm/trap_entry.h b/arch/arm/include/asm/trap_entry.h
new file mode 100644
index 0000000000000000000000000000000000000000..56cf3352c38d9347e989f9b4f6be0b7d649d9b13
--- /dev/null
+++ b/arch/arm/include/asm/trap_entry.h
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASMARM_TRAP_ENTRY_H
+#define _ASMARM_TRAP_ENTRY_H
+
+#include <asm/dovetail.h>
+#include <asm/trace/exceptions.h>
+
+#ifdef CONFIG_MMU
+#ifdef CONFIG_IRQ_PIPELINE
+/*
+ * We need to synchronize the virtual interrupt state with the hard
+ * interrupt state we received on entry, then turn hardirqs back on to
+ * allow code which does not require strict serialization to be
+ * preempted by an out-of-band activity.
+ */
+static inline unsigned long fault_entry(int exception, struct pt_regs *regs)
+{
+	unsigned long flags;
+
+	trace_ARM_trap_entry(exception, regs);
+
+	flags = hard_local_save_flags();
+
+	/*
+	 * The companion core must demote the current context to
+	 * in-band stage if running oob on entry.
+	 */
+	mark_trap_entry(exception, regs);
+
+	if (raw_irqs_disabled_flags(flags)) {
+		stall_inband();
+		trace_hardirqs_off();
+	}
+
+	hard_local_irq_enable();
+
+	return flags;
+}
+
+static inline void fault_exit(int exception, struct pt_regs *regs,
+			      unsigned long flags)
+{
+	WARN_ON_ONCE(irq_pipeline_debug() && hard_irqs_disabled());
+
+	/*
+	 * We expect kentry_exit_pipelined() to clear the stall bit if
+	 * kentry_enter_pipelined() observed it that way.
+	 */
+	mark_trap_exit(exception, regs);
+	trace_ARM_trap_exit(exception, regs);
+	hard_local_irq_restore(flags);
+}
+
+#else /* !CONFIG_IRQ_PIPELINE */
+
+#define fault_entry(__exception, __regs)		\
+	do {						\
+		(void)(__exception);			\
+		(void)(__regs);				\
+	} while (0)
+
+#define fault_exit(__exception, __regs, __flags)	\
+	do {						\
+		(void)(__exception);			\
+		(void)(__regs);				\
+		(void)(__flags);			\
+	} while (0)
+
+#endif /* !CONFIG_IRQ_PIPELINE */
+
+#else /* CONFIG_MMU */
+unsigned long fault_entry(int exception, struct pt_regs *regs)
+{
+	return 0;
+}
+
+static inline void fault_exit(int exception, struct pt_regs *regs,
+			      unsigned long combo)
+{ }
+#endif /* !CONFIG_MMU */
+
+#endif
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 7a5c0a5a825df5f76eec6aa341d910c3efa63f88..60982ec0627464dd389e1c9b106858bc92ccf260 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -24,6 +24,7 @@
 #include <asm/system_info.h>
 #include <asm/tlbflush.h>
 #include <asm/dovetail.h>
+#include <asm/trap_entry.h>
 #define CREATE_TRACE_POINTS
 #include <asm/trace/exceptions.h>
 
@@ -38,61 +39,6 @@ bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
 	return addr >= TASK_SIZE && ULONG_MAX - addr >= size;
 }
 
-#ifdef CONFIG_IRQ_PIPELINE
-/*
- * We need to synchronize the virtual interrupt state with the hard
- * interrupt state we received on entry, then turn hardirqs back on to
- * allow code which does not require strict serialization to be
- * preempted by an out-of-band activity.
- */
-static inline
-unsigned long fault_entry(int exception, struct pt_regs *regs)
-{
-	unsigned long flags;
-
-	trace_ARM_trap_entry(exception, regs);
-
-	flags = hard_local_save_flags();
-
-	/*
-	 * The companion core must demote the current context to
-	 * in-band stage if running oob on entry.
-	 */
-	mark_trap_entry(exception, regs);
-
-	if (raw_irqs_disabled_flags(flags)) {
-		stall_inband();
-		trace_hardirqs_off();
-	}
-
-	hard_local_irq_enable();
-
-	return flags;
-}
-
-static inline
-void fault_exit(int exception, struct pt_regs *regs,
-		unsigned long flags)
-{
-	WARN_ON_ONCE(irq_pipeline_debug() && hard_irqs_disabled());
-
-	/*
-	 * We expect kentry_exit_pipelined() to clear the stall bit if
-	 * kentry_enter_pipelined() observed it that way.
-	 */
-	mark_trap_exit(exception, regs);
-	trace_ARM_trap_exit(exception, regs);
-	hard_local_irq_restore(flags);
-}
-
-#else	/* !CONFIG_IRQ_PIPELINE */
-
-#define fault_entry(__exception, __regs)  ({ 0; })
-#define fault_exit(__exception, __regs, __flags)  \
-	do { (void)(__flags); } while (0)
-
-#endif	/* !CONFIG_IRQ_PIPELINE */
-
 /*
  * This is useful to dump out the page tables associated with
  * 'addr' in mm 'mm'.
@@ -165,15 +111,6 @@ void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr)
 	pr_cont("\n");
 }
 #else					/* CONFIG_MMU */
-unsigned long fault_entry(int exception, struct pt_regs *regs)
-{
-	return 0;
-}
-
-static inline void fault_exit(int exception, struct pt_regs *regs,
-			unsigned long combo)
-{ }
-
 void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr)
 { }
 #endif					/* CONFIG_MMU */

-- 
2.54.0