powerpc: add CFUNC assembly label annotation

This macro is to be used in assembly where C functions are called.
pcrel addressing mode requires branches to functions with a
localentry value of 1 to have either a trailing nop or @notoc.
This macro permits the latter without changing callers.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add dummy definitions to fix selftests build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-5-npiggin@gmail.com

arch/powerpc/include/asm/ppc_asm.h

@@ -180,6 +180,11 @@
 
 #ifdef __KERNEL__
 
+/*
+ * Used to name C functions called from asm
+ */
+#define CFUNC(name) name
+
 /*
  * We use __powerpc64__ here because we want the compat VDSO to use the 32-bit
  * version below in the else case of the ifdef.

arch/powerpc/kernel/head_64.S

@@ -608,7 +608,7 @@ __boot_from_prom:
 
 	/* Do all of the interaction with OF client interface */
 	mr	r8,r26
-	bl	prom_init
+	bl	CFUNC(prom_init)
 #endif /* #CONFIG_PPC_OF_BOOT_TRAMPOLINE */
 
 	/* We never return. We also hit that trap if trying to boot
@@ -836,7 +836,7 @@ __secondary_start:
 	 * can turn it on below. This is a call to C, which is OK, we're still
 	 * running on the emergency stack.
 	 */
-	bl	early_setup_secondary
+	bl	CFUNC(early_setup_secondary)
 
 	/*
 	 * The primary has initialized our kernel stack for us in the paca, grab
@@ -875,7 +875,7 @@ start_secondary_prolog:
 	LOAD_PACA_TOC()
 	li	r3,0
 	std	r3,0(r1)		/* Zero the stack frame pointer	*/
-	bl	start_secondary
+	bl	CFUNC(start_secondary)
 	b	.
 /*
  * Reset stack pointer and call start_secondary
@@ -886,7 +886,7 @@ _GLOBAL(start_secondary_resume)
 	ld	r1,PACAKSAVE(r13)	/* Reload kernel stack pointer */
 	li	r3,0
 	std	r3,0(r1)		/* Zero the stack frame pointer	*/
-	bl	start_secondary
+	bl	CFUNC(start_secondary)
 	b	.
 #endif
 
@@ -991,7 +991,7 @@ start_here_multiplatform:
 	 */
 
 #ifdef CONFIG_KASAN
-	bl	kasan_early_init
+	bl	CFUNC(kasan_early_init)
 #endif
 	/* Restore parameters passed from prom_init/kexec */
 	mr	r3,r31
@@ -1024,7 +1024,7 @@ start_here_common:
 	stb	r0,PACAIRQHAPPENED(r13)
 
 	/* Generic kernel entry */
-	bl	start_kernel
+	bl	CFUNC(start_kernel)
 
 	/* Not reached */
 0:	trap

arch/powerpc/kernel/interrupt_64.S

@@ -101,12 +101,12 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	 * state of kernel code.
 	 */
 	SANITIZE_SYSCALL_GPRS()
-	bl	system_call_exception
+	bl	CFUNC(system_call_exception)
 
 .Lsyscall_vectored_\name\()_exit:
 	addi	r4,r1,STACK_INT_FRAME_REGS
 	li	r5,1 /* scv */
-	bl	syscall_exit_prepare
+	bl	CFUNC(syscall_exit_prepare)
 	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
 .Lsyscall_vectored_\name\()_rst_start:
 	lbz	r11,PACAIRQHAPPENED(r13)
@@ -185,7 +185,7 @@ _ASM_NOKPROBE_SYMBOL(syscall_vectored_\name\()_restart)
 	addi	r4,r1,STACK_INT_FRAME_REGS
 	li	r11,IRQS_ALL_DISABLED
 	stb	r11,PACAIRQSOFTMASK(r13)
-	bl	syscall_exit_restart
+	bl	CFUNC(syscall_exit_restart)
 	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
 	b	.Lsyscall_vectored_\name\()_rst_start
 1:
@@ -286,12 +286,12 @@ END_BTB_FLUSH_SECTION
 	 * state of kernel code.
 	 */
 	SANITIZE_SYSCALL_GPRS()
-	bl	system_call_exception
+	bl	CFUNC(system_call_exception)
 
 .Lsyscall_exit:
 	addi	r4,r1,STACK_INT_FRAME_REGS
 	li	r5,0 /* !scv */
-	bl	syscall_exit_prepare
+	bl	CFUNC(syscall_exit_prepare)
 	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
 #ifdef CONFIG_PPC_BOOK3S
 .Lsyscall_rst_start:
@@ -372,7 +372,7 @@ _ASM_NOKPROBE_SYMBOL(syscall_restart)
 	addi	r4,r1,STACK_INT_FRAME_REGS
 	li	r11,IRQS_ALL_DISABLED
 	stb	r11,PACAIRQSOFTMASK(r13)
-	bl	syscall_exit_restart
+	bl	CFUNC(syscall_exit_restart)
 	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
 	b	.Lsyscall_rst_start
 1:
@@ -401,7 +401,7 @@ _ASM_NOKPROBE_SYMBOL(fast_interrupt_return_srr)
 	li	r3,0 /* 0 return value, no EMULATE_STACK_STORE */
 	bne+	.Lfast_kernel_interrupt_return_srr
 	addi	r3,r1,STACK_INT_FRAME_REGS
-	bl	unrecoverable_exception
+	bl	CFUNC(unrecoverable_exception)
 	b	. /* should not get here */
 #else
 	bne	.Lfast_user_interrupt_return_srr
@@ -419,7 +419,7 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\())
 interrupt_return_\srr\()_user: /* make backtraces match the _kernel variant */
 _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user)
 	addi	r3,r1,STACK_INT_FRAME_REGS
-	bl	interrupt_exit_user_prepare
+	bl	CFUNC(interrupt_exit_user_prepare)
 #ifndef CONFIG_INTERRUPT_SANITIZE_REGISTERS
 	cmpdi	r3,0
 	bne-	.Lrestore_nvgprs_\srr
@@ -523,7 +523,7 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user_restart)
 	addi	r3,r1,STACK_INT_FRAME_REGS
 	li	r11,IRQS_ALL_DISABLED
 	stb	r11,PACAIRQSOFTMASK(r13)
-	bl	interrupt_exit_user_restart
+	bl	CFUNC(interrupt_exit_user_restart)
 	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
 	b	.Linterrupt_return_\srr\()_user_rst_start
 1:
@@ -536,7 +536,7 @@ RESTART_TABLE(.Linterrupt_return_\srr\()_user_rst_start, .Linterrupt_return_\srr
 interrupt_return_\srr\()_kernel:
 _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel)
 	addi	r3,r1,STACK_INT_FRAME_REGS
-	bl	interrupt_exit_kernel_prepare
+	bl	CFUNC(interrupt_exit_kernel_prepare)
 
 	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
 .Linterrupt_return_\srr\()_kernel_rst_start:
@@ -705,7 +705,7 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel_restart)
 	addi	r3,r1,STACK_INT_FRAME_REGS
 	li	r11,IRQS_ALL_DISABLED
 	stb	r11,PACAIRQSOFTMASK(r13)
-	bl	interrupt_exit_kernel_restart
+	bl	CFUNC(interrupt_exit_kernel_restart)
 	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
 	b	.Linterrupt_return_\srr\()_kernel_rst_start
 1:
@@ -727,20 +727,20 @@ DEFINE_FIXED_SYMBOL(__end_soft_masked, text)
 
 #ifdef CONFIG_PPC_BOOK3S
 _GLOBAL(ret_from_fork_scv)
-	bl	schedule_tail
+	bl	CFUNC(schedule_tail)
 	HANDLER_RESTORE_NVGPRS()
 	li	r3,0	/* fork() return value */
 	b	.Lsyscall_vectored_common_exit
 #endif
 
 _GLOBAL(ret_from_fork)
-	bl	schedule_tail
+	bl	CFUNC(schedule_tail)
 	HANDLER_RESTORE_NVGPRS()
 	li	r3,0	/* fork() return value */
 	b	.Lsyscall_exit
 
 _GLOBAL(ret_from_kernel_user_thread)
-	bl	schedule_tail
+	bl	CFUNC(schedule_tail)
 	mtctr	r14
 	mr	r3,r15
 #ifdef CONFIG_PPC64_ELF_ABI_V2

arch/powerpc/kernel/misc_64.S

@@ -432,7 +432,7 @@ _GLOBAL(kexec_sequence)
 1:
 	/* copy dest pages, flush whole dest image */
 	mr	r3,r29
-	bl	kexec_copy_flush	/* (image) */
+	bl	CFUNC(kexec_copy_flush)	/* (image) */
 
 	/* turn off mmu now if not done earlier */
 	cmpdi	r26,0

arch/powerpc/kernel/vdso/gettimeofday.S

@@ -38,7 +38,11 @@
 	.else
 	addi		r4, r5, VDSO_DATA_OFFSET
 	.endif
-	bl		DOTSYM(\funct)
+#ifdef __powerpc64__
+	bl		CFUNC(DOTSYM(\funct))
+#else
+	bl		\funct
+#endif
 	PPC_LL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
 #ifdef __powerpc64__
 	PPC_LL		r2, PPC_MIN_STKFRM + STK_GOT(r1)

arch/powerpc/kvm/book3s_hv_rmhandlers.S

@@ -381,7 +381,7 @@ kvm_secondary_got_guest:
 	bne	kvm_no_guest
 
 	li	r3,0			/* NULL argument */
-	bl	hmi_exception_realmode
+	bl	CFUNC(hmi_exception_realmode)
 /*
  * At this point we have finished executing in the guest.
  * We need to wait for hwthread_req to become zero, since
@@ -458,7 +458,7 @@ kvm_unsplit_nap:
 	cmpwi	r12, BOOK3S_INTERRUPT_HMI
 	bne	55f
 	li	r3, 0			/* NULL argument */
-	bl	hmi_exception_realmode
+	bl	CFUNC(hmi_exception_realmode)
 55:
 	/*
 	 * Ensure that secondary doesn't nap when it has
@@ -858,7 +858,7 @@ deliver_guest_interrupt:	/* r4 = vcpu, r13 = paca */
 	cmpdi	r0, 0
 	beq	71f
 	mr	r3, r4
-	bl	kvmppc_guest_entry_inject_int
+	bl	CFUNC(kvmppc_guest_entry_inject_int)
 	ld	r4, HSTATE_KVM_VCPU(r13)
 71:
 	ld	r6, VCPU_SRR0(r4)
@@ -1544,7 +1544,7 @@ kvmppc_guest_external:
 	/* External interrupt, first check for host_ipi. If this is
 	 * set, we know the host wants us out so let's do it now
 	 */
-	bl	kvmppc_read_intr
+	bl	CFUNC(kvmppc_read_intr)
 
 	/*
 	 * Restore the active volatile registers after returning from
@@ -1626,7 +1626,7 @@ kvmppc_hdsi:
 	/* Search the hash table. */
 	mr	r3, r9			/* vcpu pointer */
 	li	r7, 1			/* data fault */
-	bl	kvmppc_hpte_hv_fault
+	bl	CFUNC(kvmppc_hpte_hv_fault)
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	ld	r10, VCPU_PC(r9)
 	ld	r11, VCPU_MSR(r9)
@@ -1702,7 +1702,7 @@ kvmppc_hisi:
 	mr	r4, r10
 	mr	r6, r11
 	li	r7, 0			/* instruction fault */
-	bl	kvmppc_hpte_hv_fault
+	bl	CFUNC(kvmppc_hpte_hv_fault)
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	ld	r10, VCPU_PC(r9)
 	ld	r11, VCPU_MSR(r9)
@@ -2342,7 +2342,7 @@ hmi_realmode:
 	lbz	r0, HSTATE_PTID(r13)
 	cmpwi	r0, 0
 	bne	guest_exit_cont
-	bl	kvmppc_realmode_hmi_handler
+	bl	CFUNC(kvmppc_realmode_hmi_handler)
 	ld	r9, HSTATE_KVM_VCPU(r13)
 	li	r12, BOOK3S_INTERRUPT_HMI
 	b	guest_exit_cont
@@ -2413,7 +2413,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 7:	mflr	r0
 	std	r0, PPC_LR_STKOFF(r1)
 	stdu	r1, -PPC_MIN_STKFRM(r1)
-	bl	kvmppc_read_intr
+	bl	CFUNC(kvmppc_read_intr)
 	nop
 	li	r12, BOOK3S_INTERRUPT_EXTERNAL
 	cmpdi	r3, 1

arch/powerpc/lib/copypage_power7.S

@@ -45,7 +45,7 @@ _GLOBAL(copypage_power7)
 	std	r4,-STACKFRAMESIZE+STK_REG(R30)(r1)
 	std	r0,16(r1)
 	stdu	r1,-STACKFRAMESIZE(r1)
-	bl	enter_vmx_ops
+	bl	CFUNC(enter_vmx_ops)
 	cmpwi	r3,0
 	ld	r0,STACKFRAMESIZE+16(r1)
 	ld	r3,STK_REG(R31)(r1)
@@ -88,7 +88,7 @@ _GLOBAL(copypage_power7)
 	addi	r3,r3,128
 	bdnz	1b
 
-	b	exit_vmx_ops		/* tail call optimise */
+	b	CFUNC(exit_vmx_ops)		/* tail call optimise */
 
 #else
 	li	r0,(PAGE_SIZE/128)

arch/powerpc/lib/copyuser_power7.S

@@ -47,7 +47,7 @@
 	ld	r15,STK_REG(R15)(r1)
 	ld	r14,STK_REG(R14)(r1)
 .Ldo_err3:
-	bl	exit_vmx_usercopy
+	bl	CFUNC(exit_vmx_usercopy)
 	ld	r0,STACKFRAMESIZE+16(r1)
 	mtlr	r0
 	b	.Lexit
@@ -272,7 +272,7 @@ err1;	stb	r0,0(r3)
 	mflr	r0
 	std	r0,16(r1)
 	stdu	r1,-STACKFRAMESIZE(r1)
-	bl	enter_vmx_usercopy
+	bl	CFUNC(enter_vmx_usercopy)
 	cmpwi	cr1,r3,0
 	ld	r0,STACKFRAMESIZE+16(r1)
 	ld	r3,STK_REG(R31)(r1)
@@ -488,7 +488,7 @@ err3;	lbz	r0,0(r4)
 err3;	stb	r0,0(r3)
 
 15:	addi	r1,r1,STACKFRAMESIZE
-	b	exit_vmx_usercopy	/* tail call optimise */
+	b	CFUNC(exit_vmx_usercopy)	/* tail call optimise */
 
 .Lvmx_unaligned_copy:
 	/* Get the destination 16B aligned */
@@ -691,5 +691,5 @@ err3;	lbz	r0,0(r4)
 err3;	stb	r0,0(r3)
 
 15:	addi	r1,r1,STACKFRAMESIZE
-	b	exit_vmx_usercopy	/* tail call optimise */
+	b	CFUNC(exit_vmx_usercopy)	/* tail call optimise */
 #endif /* CONFIG_ALTIVEC */

arch/powerpc/lib/hweight_64.S

@@ -14,7 +14,7 @@
 
 _GLOBAL(__arch_hweight8)
 BEGIN_FTR_SECTION
-	b __sw_hweight8
+	b CFUNC(__sw_hweight8)
 	nop
 	nop
 FTR_SECTION_ELSE
@@ -26,7 +26,7 @@ EXPORT_SYMBOL(__arch_hweight8)
 
 _GLOBAL(__arch_hweight16)
 BEGIN_FTR_SECTION
-	b __sw_hweight16
+	b CFUNC(__sw_hweight16)
 	nop
 	nop
 	nop
@@ -49,7 +49,7 @@ EXPORT_SYMBOL(__arch_hweight16)
 
 _GLOBAL(__arch_hweight32)
 BEGIN_FTR_SECTION
-	b __sw_hweight32
+	b CFUNC(__sw_hweight32)
 	nop
 	nop
 	nop
@@ -75,7 +75,7 @@ EXPORT_SYMBOL(__arch_hweight32)
 
 _GLOBAL(__arch_hweight64)
 BEGIN_FTR_SECTION
-	b __sw_hweight64
+	b CFUNC(__sw_hweight64)
 	nop
 	nop
 	nop

arch/powerpc/lib/memcmp_64.S

@@ -44,7 +44,7 @@
 	std     r5,-STACKFRAMESIZE+STK_REG(R29)(r1); \
 	std     r0,16(r1); \
 	stdu    r1,-STACKFRAMESIZE(r1); \
-	bl      enter_vmx_ops; \
+	bl      CFUNC(enter_vmx_ops); \
 	cmpwi   cr1,r3,0; \
 	ld      r0,STACKFRAMESIZE+16(r1); \
 	ld      r3,STK_REG(R31)(r1); \
@@ -60,7 +60,7 @@
 	std     r5,-STACKFRAMESIZE+STK_REG(R29)(r1); \
 	std     r0,16(r1); \
 	stdu    r1,-STACKFRAMESIZE(r1); \
-	bl      exit_vmx_ops; \
+	bl      CFUNC(exit_vmx_ops); \
 	ld      r0,STACKFRAMESIZE+16(r1); \
 	ld      r3,STK_REG(R31)(r1); \
 	ld      r4,STK_REG(R30)(r1); \

arch/powerpc/lib/memcpy_power7.S

@@ -218,7 +218,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	std	r5,-STACKFRAMESIZE+STK_REG(R29)(r1)
 	std	r0,16(r1)
 	stdu	r1,-STACKFRAMESIZE(r1)
-	bl	enter_vmx_ops
+	bl	CFUNC(enter_vmx_ops)
 	cmpwi	cr1,r3,0
 	ld	r0,STACKFRAMESIZE+16(r1)
 	ld	r3,STK_REG(R31)(r1)
@@ -433,7 +433,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 
 15:	addi	r1,r1,STACKFRAMESIZE
 	ld	r3,-STACKFRAMESIZE+STK_REG(R31)(r1)
-	b	exit_vmx_ops		/* tail call optimise */
+	b	CFUNC(exit_vmx_ops)		/* tail call optimise */
 
 .Lvmx_unaligned_copy:
 	/* Get the destination 16B aligned */
@@ -637,5 +637,5 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 
 15:	addi	r1,r1,STACKFRAMESIZE
 	ld	r3,-STACKFRAMESIZE+STK_REG(R31)(r1)
-	b	exit_vmx_ops		/* tail call optimise */
+	b	CFUNC(exit_vmx_ops)		/* tail call optimise */
 #endif /* CONFIG_ALTIVEC */

arch/powerpc/platforms/pseries/hvCall.S

@@ -44,7 +44,7 @@ hcall_tracepoint_refcount:
 	std	r0,16(r1);					\
 	addi	r4,r1,STK_PARAM(FIRST_REG);			\
 	stdu	r1,-STACK_FRAME_MIN_SIZE(r1);			\
-	bl	__trace_hcall_entry;				\
+	bl	CFUNC(__trace_hcall_entry);			\
 	ld	r3,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1);	\
 	ld	r4,STACK_FRAME_MIN_SIZE+STK_PARAM(R4)(r1);	\
 	ld	r5,STACK_FRAME_MIN_SIZE+STK_PARAM(R5)(r1);	\
@@ -63,7 +63,7 @@ hcall_tracepoint_refcount:
 	std	r3,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1);	\
 	mr	r4,r3;						\
 	mr	r3,r0;						\
-	bl	__trace_hcall_exit;				\
+	bl	CFUNC(__trace_hcall_exit);			\
 	ld	r0,STACK_FRAME_MIN_SIZE+16(r1);			\
 	addi	r1,r1,STACK_FRAME_MIN_SIZE;			\
 	ld	r3,STK_PARAM(R3)(r1);				\

tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h

@@ -27,6 +27,7 @@
 #define _GLOBAL_TOC(A) _GLOBAL(A)
 #define _GLOBAL_TOC_KASAN(A) _GLOBAL(A)
 #define _GLOBAL_KASAN(A) _GLOBAL(A)
+#define CFUNC(name) name
 
 #define PPC_MTOCRF(A, B)	mtocrf A, B
 

tools/testing/selftests/powerpc/stringloops/asm/ppc_asm.h

@@ -9,6 +9,7 @@
 
 #define _GLOBAL(A) FUNC_START(test_ ## A)
 #define _GLOBAL_TOC(A) FUNC_START(test_ ## A)
+#define CFUNC(name) name
 
 #define CONFIG_ALTIVEC