powerpc/32: Call bad_page_fault() from do_page_fault()

Now that non volatile registers are saved at all time, no
need to split bad_page_fault() out of do_page_fault().

Remove handle_page_fault() and use do_page_fault() directly.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/cfb95be8863204cc2bf45a22ea44dd1d0dc16b7f.1615552867.git.christophe.leroy@csgroup.eu

arch/powerpc/kernel/entry_32.S

@@ -220,22 +220,6 @@ ret_from_kernel_thread:
 	li	r3,0
 	b	ret_from_syscall
 
-/*
- * Top-level page fault handling.
- * This is in assembler because if do_page_fault tells us that
- * it is a bad kernel page fault, we want to save the non-volatile
- * registers before calling bad_page_fault.
- */
-	.globl	handle_page_fault
-handle_page_fault:
-	bl	do_page_fault
-	cmpwi	r3,0
-	beq+	ret_from_except
-	mr	r4,r3		/* err arg for bad_page_fault */
-	addi	r3,r1,STACK_FRAME_OVERHEAD
-	bl	__bad_page_fault
-	b	ret_from_except_full
-
 /*
  * This routine switches between two different tasks.  The process
  * state of one is saved on its kernel stack.  Then the state

arch/powerpc/kernel/head_40x.S

@@ -207,7 +207,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
  */
 	START_EXCEPTION(0x0300,	DataStorage)
 	EXCEPTION_PROLOG DataStorage handle_dar_dsisr=1
-	EXC_XFER_LITE(0x300, handle_page_fault)
+	EXC_XFER_LITE(0x300, do_page_fault)
 
 /*
  * 0x0400 - Instruction Storage Exception
@@ -218,7 +218,7 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
 	li	r5,0
 	stw	r5, _ESR(r11)		/* Zero ESR */
 	stw	r12, _DEAR(r11)		/* SRR0 as DEAR */
-	EXC_XFER_LITE(0x400, handle_page_fault)
+	EXC_XFER_LITE(0x400, do_page_fault)
 
 /* 0x0500 - External Interrupt Exception */
 	EXCEPTION(0x0500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE)

arch/powerpc/kernel/head_8xx.S

@@ -301,7 +301,7 @@ instruction_counter:
 .Litlbie:
 	stw	r12, _DAR(r11)
 	stw	r5, _DSISR(r11)
-	EXC_XFER_LITE(0x400, handle_page_fault)
+	EXC_XFER_LITE(0x400, do_page_fault)
 
 /* This is the data TLB error on the MPC8xx.  This could be due to
  * many reasons, including a dirty update to a pte.  We bail out to
@@ -322,7 +322,7 @@ DARFixed:/* Return from dcbx instruction bug workaround */
 	tlbie	r4
 .Ldtlbie:
 	/* 0x300 is DataAccess exception, needed by bad_page_fault() */
-	EXC_XFER_LITE(0x300, handle_page_fault)
+	EXC_XFER_LITE(0x300, do_page_fault)
 
 #ifdef CONFIG_VMAP_STACK
 	vmap_stack_overflow_exception

arch/powerpc/kernel/head_book3s_32.S

@@ -299,7 +299,7 @@ ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_HPTE_TABLE)
 	lwz	r5, _DSISR(r11)
 	andis.	r0, r5, DSISR_DABRMATCH@h
 	bne-	1f
-	EXC_XFER_LITE(0x300, handle_page_fault)
+	EXC_XFER_LITE(0x300, do_page_fault)
 1:	EXC_XFER_STD(0x300, do_break)
 
 
@@ -328,7 +328,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
 	andis.	r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
 	stw	r5, _DSISR(r11)
 	stw	r12, _DAR(r11)
-	EXC_XFER_LITE(0x400, handle_page_fault)
+	EXC_XFER_LITE(0x400, do_page_fault)
 
 /* External interrupt */
 	EXCEPTION(0x500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE)

arch/powerpc/kernel/head_booke.h

@@ -462,7 +462,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
 	stw	r5,_ESR(r11);						      \
 	mfspr	r4,SPRN_DEAR;		/* Grab the DEAR */		      \
 	stw	r4, _DEAR(r11);						      \
-	EXC_XFER_LITE(0x0300, handle_page_fault)
+	EXC_XFER_LITE(0x0300, do_page_fault)
 
 #define INSTRUCTION_STORAGE_EXCEPTION					      \
 	START_EXCEPTION(InstructionStorage)				      \
@@ -470,7 +470,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
 	mfspr	r5,SPRN_ESR;		/* Grab the ESR and save it */	      \
 	stw	r5,_ESR(r11);						      \
 	stw	r12, _DEAR(r11);	/* Pass SRR0 as arg2 */		      \
-	EXC_XFER_LITE(0x0400, handle_page_fault)
+	EXC_XFER_LITE(0x0400, do_page_fault)
 
 #define ALIGNMENT_EXCEPTION						      \
 	START_EXCEPTION(Alignment)					      \

arch/powerpc/kernel/head_fsl_booke.S

@@ -370,7 +370,7 @@ interrupt_base:
 	stw	r4, _DEAR(r11)
 	andis.	r10,r5,(ESR_ILK|ESR_DLK)@h
 	bne	1f
-	EXC_XFER_LITE(0x0300, handle_page_fault)
+	EXC_XFER_LITE(0x0300, do_page_fault)
 1:
 	EXC_XFER_LITE(0x0300, CacheLockingException)
 

arch/powerpc/mm/fault.c

@@ -557,7 +557,7 @@ static long __do_page_fault(struct pt_regs *regs)
 	if (likely(entry)) {
 		instruction_pointer_set(regs, extable_fixup(entry));
 		return 0;
-	} else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64)) {
+	} else if (!IS_ENABLED(CONFIG_PPC_BOOK3E_64)) {
 		__bad_page_fault(regs, err);
 		return 0;
 	} else {