[RFC PATCH v1 28/41] powerpc/32: Add a prepare_transfer_to_handler macro for exception prologs

[Christophe Leroy]

In order to increase flexibility, add a macro that will for now
call transfer_to_handler.

As transfer_to_handler doesn't do the actual transfer anymore,
also name it prepare_transfer_to_handler. The following patches
will progressively remove the use of transfer_to_handler label.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
 arch/powerpc/kernel/entry_32.S   | 3 +++
 arch/powerpc/kernel/head_32.h    | 4 ++++
 arch/powerpc/kernel/head_booke.h | 4 ++++
 3 files changed, 11 insertions(+)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 890a4508c1f1..03f4d07f4176 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -86,6 +86,8 @@ _ASM_NOKPROBE_SYMBOL(transfer_to_handler_full)
 
 	.globl	transfer_to_handler
 transfer_to_handler:
+	.globl	prepare_transfer_to_handler
+prepare_transfer_to_handler:
 	SAVE_NVGPRS(r11)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	stw	r2,GPR2(r11)
@@ -133,6 +135,7 @@ transfer_to_handler_cont:
 	stw	r9,_MSR(r11)
 	b	fast_exception_return
 #endif
+_ASM_NOKPROBE_SYMBOL(prepare_transfer_to_handler)
 _ASM_NOKPROBE_SYMBOL(transfer_to_handler)
 _ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont)
 
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index bf4c288173ad..3ab0f3ad9a6a 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -115,6 +115,10 @@
 _ASM_NOKPROBE_SYMBOL(\name\()_virt)
 .endm
 
+.macro prepare_transfer_to_handler
+	bl	prepare_transfer_to_handler
+.endm
+
 .macro SYSCALL_ENTRY trapno
 	mfspr	r9, SPRN_SRR1
 	mfspr	r10, SPRN_SRR0
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index 12add20edbb1..9bc86aab65ef 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -87,6 +87,10 @@ END_BTB_FLUSH_SECTION
 	SAVE_4GPRS(3, r11);						     \
 	SAVE_2GPRS(7, r11)
 
+.macro prepare_transfer_to_handler
+	bl	prepare_transfer_to_handler
+.endm
+
 .macro SYSCALL_ENTRY trapno intno srr1
 	mfspr	r10, SPRN_SPRG_THREAD
 #ifdef CONFIG_KVM_BOOKE_HV
-- 
2.25.0