From 3be2d89cade41c775cdcdce27cdfa0758d26d1a9 Mon Sep 17 00:00:00 2001
From: Mark Rutland <mark.rutland@arm.com>
Date: Thu, 3 Nov 2016 20:23:05 +0000
Subject: [PATCH] UPSTREAM: arm64: factor out current_stack_pointer

We define current_stack_pointer in <asm/thread_info.h>, though other
files and header relying upon it do not have this necessary include, and
are thus fragile to changes in the header soup.

Subsequent patches will affect the header soup such that directly
including <asm/thread_info.h> may result in a circular header include in
some of these cases, so we can't simply include <asm/thread_info.h>.

Instead, factor current_thread_info into its own header, and have all
existing users include this explicitly.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Bug: 38331309
Change-Id: I4d6bc27bef686d0dade1d6abe1ce947cf6c4dfb3
(cherry picked from commit a9ea0017ebe8889dfa136cac2aa7ae0ee6915e1f)
Signed-off-by: Zubin Mithra <zsm@google.com>
---
 arch/arm64/include/asm/percpu.h        | 2 ++
 arch/arm64/include/asm/perf_event.h    | 2 ++
 arch/arm64/include/asm/stack_pointer.h | 9 +++++++++
 arch/arm64/include/asm/thread_info.h   | 6 +-----
 arch/arm64/kernel/return_address.c     | 1 +
 arch/arm64/kernel/stacktrace.c         | 1 +
 arch/arm64/kernel/traps.c              | 1 +
 7 files changed, 17 insertions(+), 5 deletions(-)
 create mode 100644 arch/arm64/include/asm/stack_pointer.h

diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h
index 8a336852eeba..2ce1a0262a59 100644
--- a/arch/arm64/include/asm/percpu.h
+++ b/arch/arm64/include/asm/percpu.h
@@ -16,6 +16,8 @@
 #ifndef __ASM_PERCPU_H
 #define __ASM_PERCPU_H
 
+#include <asm/stack_pointer.h>
+
 static inline void set_my_cpu_offset(unsigned long off)
 {
 	asm volatile("msr tpidr_el1, %0" :: "r" (off) : "memory");
diff --git a/arch/arm64/include/asm/perf_event.h b/arch/arm64/include/asm/perf_event.h
index 7bd3cdb533ea..91b6be092ce2 100644
--- a/arch/arm64/include/asm/perf_event.h
+++ b/arch/arm64/include/asm/perf_event.h
@@ -17,6 +17,8 @@
 #ifndef __ASM_PERF_EVENT_H
 #define __ASM_PERF_EVENT_H
 
+#include <asm/stack_pointer.h>
+
 #ifdef CONFIG_PERF_EVENTS
 struct pt_regs;
 extern unsigned long perf_instruction_pointer(struct pt_regs *regs);
diff --git a/arch/arm64/include/asm/stack_pointer.h b/arch/arm64/include/asm/stack_pointer.h
new file mode 100644
index 000000000000..ffcdf742cddf
--- /dev/null
+++ b/arch/arm64/include/asm/stack_pointer.h
@@ -0,0 +1,9 @@
+#ifndef __ASM_STACK_POINTER_H
+#define __ASM_STACK_POINTER_H
+
+/*
+ * how to get the current stack pointer from C
+ */
+register unsigned long current_stack_pointer asm ("sp");
+
+#endif /* __ASM_STACK_POINTER_H */
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
index 9224bf2d59d5..41e4fd78e345 100644
--- a/arch/arm64/include/asm/thread_info.h
+++ b/arch/arm64/include/asm/thread_info.h
@@ -36,6 +36,7 @@
 
 struct task_struct;
 
+#include <asm/stack_pointer.h>
 #include <asm/types.h>
 
 typedef unsigned long mm_segment_t;
@@ -64,11 +65,6 @@ struct thread_info {
 
 #define init_stack		(init_thread_union.stack)
 
-/*
- * how to get the current stack pointer from C
- */
-register unsigned long current_stack_pointer asm ("sp");
-
 /*
  * how to get the thread information struct from C
  */
diff --git a/arch/arm64/kernel/return_address.c b/arch/arm64/kernel/return_address.c
index 1718706fde83..12a87f2600f2 100644
--- a/arch/arm64/kernel/return_address.c
+++ b/arch/arm64/kernel/return_address.c
@@ -12,6 +12,7 @@
 #include <linux/export.h>
 #include <linux/ftrace.h>
 
+#include <asm/stack_pointer.h>
 #include <asm/stacktrace.h>
 
 struct return_address_data {
diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index a99eff9afc1f..4a93c5e68c48 100644
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -22,6 +22,7 @@
 #include <linux/stacktrace.h>
 
 #include <asm/irq.h>
+#include <asm/stack_pointer.h>
 #include <asm/stacktrace.h>
 
 /*
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index a1cfcaa562a2..d7205de524f0 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -38,6 +38,7 @@
 #include <asm/esr.h>
 #include <asm/insn.h>
 #include <asm/traps.h>
+#include <asm/stack_pointer.h>
 #include <asm/stacktrace.h>
 #include <asm/exception.h>
 #include <asm/system_misc.h>