powerpc: Define and use PPC64_ELF_ABI_v2/v1

We're approaching 20 locations where we need to check for ELF ABI v2.
That's fine, except the logic is a bit awkward, because we have to check
that _CALL_ELF is defined and then what its value is.

So check it once in asm/types.h and define PPC64_ELF_ABI_v2 when ELF ABI
v2 is detected.

We also have a few places where what we're really trying to check is
that we are using the 64-bit v1 ABI, ie. function descriptors. So also
add a #define for that, which simplifies several checks.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

16 files changed, 39 insertions, 35 deletions

diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h
index 994c60a857ce..2015b072422c 100644
--- a/arch/powerpc/include/asm/code-patching.h
+++ b/arch/powerpc/include/asm/code-patching.h
@@ -49,8 +49,7 @@ void __patch_exception(int exc, unsigned long addr);
 
 static inline unsigned long ppc_function_entry(void *func)
 {
-#if defined(CONFIG_PPC64)
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
         u32 *insn = func;
 
         /*
@@ -75,14 +74,13 @@ static inline unsigned long ppc_function_entry(void *func)
                 return (unsigned long)(insn + 2);
         else
                 return (unsigned long)func;
-#else
+#elif defined(PPC64_ELF_ABI_v1)
         /*
          * On PPC64 ABIv1 the function pointer actually points to the
          * function's descriptor. The first entry in the descriptor is the
          * address of the function text.
          */
         return ((func_descr_t *)func)->entry;
-#endif
 #else
         return (unsigned long)func;
 #endif
@@ -90,7 +88,7 @@ static inline unsigned long ppc_function_entry(void *func)
 
 static inline unsigned long ppc_global_function_entry(void *func)
 {
-#if defined(CONFIG_PPC64) && defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
         /* PPC64 ABIv2 the global entry point is at the address */
         return (unsigned long)func;
 #else
@@ -106,7 +104,7 @@ static inline unsigned long ppc_global_function_entry(void *func)
  */
 
 /* This must match the definition of STK_GOT in <asm/ppc_asm.h> */
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
 #define R2_STACK_OFFSET         24
 #else
 #define R2_STACK_OFFSET         40
diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h
index 50ca7585abe2..686c5f70eb84 100644
--- a/arch/powerpc/include/asm/ftrace.h
+++ b/arch/powerpc/include/asm/ftrace.h
@@ -1,6 +1,8 @@
 #ifndef _ASM_POWERPC_FTRACE
 #define _ASM_POWERPC_FTRACE
 
+#include <asm/types.h>
+
 #ifdef CONFIG_FUNCTION_TRACER
 #define MCOUNT_ADDR             ((unsigned long)(_mcount))
 #define MCOUNT_INSN_SIZE        4 /* sizeof mcount call */
@@ -65,8 +67,8 @@ struct dyn_arch_ftrace {
 #endif
 #endif
 
-#if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_PPC64) && !defined(__ASSEMBLY__)
-#if !defined(_CALL_ELF) || _CALL_ELF != 2
+#if defined(CONFIG_FTRACE_SYSCALLS) && !defined(__ASSEMBLY__)
+#ifdef PPC64_ELF_ABI_v1
 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
 {
@@ -79,6 +81,6 @@ static inline bool arch_syscall_match_sym_name(const char *sym, const char *name
         return !strcmp(sym + 4, name + 3);
 }
 #endif
-#endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_PPC64 && !__ASSEMBLY__ */
+#endif /* CONFIG_FTRACE_SYSCALLS && !__ASSEMBLY__ */
 
 #endif /* _ASM_POWERPC_FTRACE */
diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h
index 039b583db029..2c9759bdb63b 100644
--- a/arch/powerpc/include/asm/kprobes.h
+++ b/arch/powerpc/include/asm/kprobes.h
@@ -40,8 +40,7 @@ struct kprobe;
 typedef ppc_opcode_t kprobe_opcode_t;
 #define MAX_INSN_SIZE 1
 
-#ifdef CONFIG_PPC64
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
 /* PPC64 ABIv2 needs local entry point */
 #define kprobe_lookup_name(name, addr)                                  \
 {                                                                       \
@@ -49,7 +48,7 @@ typedef ppc_opcode_t kprobe_opcode_t;
         if (addr)                                                       \
                 addr = (kprobe_opcode_t *)ppc_function_entry(addr);     \
 }
-#else
+#elif defined(PPC64_ELF_ABI_v1)
 /*
  * 64bit powerpc ABIv1 uses function descriptors:
  * - Check for the dot variant of the symbol first.
@@ -92,8 +91,7 @@ typedef ppc_opcode_t kprobe_opcode_t;
                 addr = (kprobe_opcode_t *)kallsyms_lookup_name(name);   \
         }                                                               \
 }
-#endif /* defined(_CALL_ELF) && _CALL_ELF == 2 */
-#endif /* CONFIG_PPC64 */
+#endif
 
 #define flush_insn_slot(p)      do { } while (0)
 #define kretprobe_blacklist_size 0
diff --git a/arch/powerpc/include/asm/linkage.h b/arch/powerpc/include/asm/linkage.h
index e3ad5c72724a..0cf5e21179fc 100644
--- a/arch/powerpc/include/asm/linkage.h
+++ b/arch/powerpc/include/asm/linkage.h
@@ -1,8 +1,9 @@
 #ifndef _ASM_POWERPC_LINKAGE_H
 #define _ASM_POWERPC_LINKAGE_H
 
-#ifdef CONFIG_PPC64
-#if !defined(_CALL_ELF) || _CALL_ELF != 2
+#include <asm/types.h>
+
+#ifdef PPC64_ELF_ABI_v1
 #define cond_syscall(x) \
         asm ("\t.weak " #x "\n\t.set " #x ", sys_ni_syscall\n"          \
              "\t.weak ." #x "\n\t.set ." #x ", .sys_ni_syscall\n")
@@ -10,6 +11,5 @@
         asm ("\t.globl " #alias "\n\t.set " #alias ", " #name "\n"      \
              "\t.globl ." #alias "\n\t.set ." #alias ", ." #name)
 #endif
-#endif
 
 #endif  /* _ASM_POWERPC_LINKAGE_H */
diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index 2b31632376a5..7b591f98edcc 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -189,7 +189,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
 #define __STK_REG(i)   (112 + ((i)-14)*8)
 #define STK_REG(i)     __STK_REG(__REG_##i)
 
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
 #define STK_GOT         24
 #define __STK_PARAM(i)  (32 + ((i)-3)*8)
 #else
@@ -198,7 +198,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
 #endif
 #define STK_PARAM(i)    __STK_PARAM(__REG_##i)
 
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
 
 #define _GLOBAL(name) \
         .section ".text"; \
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index c0c61fa9cd9e..e4923686e43a 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -47,7 +47,7 @@
                                  STACK_FRAME_OVERHEAD + KERNEL_REDZONE_SIZE)
 #define STACK_FRAME_MARKER      12
 
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
 #define STACK_FRAME_MIN_SIZE    32
 #else
 #define STACK_FRAME_MIN_SIZE    STACK_FRAME_OVERHEAD
diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h
index abf5866e08c6..7dc006b58369 100644
--- a/arch/powerpc/include/asm/sections.h
+++ b/arch/powerpc/include/asm/sections.h
@@ -62,7 +62,7 @@ static inline int overlaps_kvm_tmp(unsigned long start, unsigned long end)
 #endif
 }
 
-#if !defined(_CALL_ELF) || _CALL_ELF != 2
+#ifdef PPC64_ELF_ABI_v1
 #undef dereference_function_descriptor
 static inline void *dereference_function_descriptor(void *ptr)
 {
@@ -73,7 +73,7 @@ static inline void *dereference_function_descriptor(void *ptr)
                 ptr = p;
         return ptr;
 }
-#endif
+#endif /* PPC64_ELF_ABI_v1 */
 
 #endif
 
diff --git a/arch/powerpc/include/asm/types.h b/arch/powerpc/include/asm/types.h
index bfb6ded38ffa..49a0678a53fa 100644
--- a/arch/powerpc/include/asm/types.h
+++ b/arch/powerpc/include/asm/types.h
@@ -15,6 +15,14 @@
 
 #include <uapi/asm/types.h>
 
+#ifdef __powerpc64__
+#if defined(_CALL_ELF) && _CALL_ELF == 2
+#define PPC64_ELF_ABI_v2
+#else
+#define PPC64_ELF_ABI_v1
+#endif
+#endif /* __powerpc64__ */
+
 #ifndef __ASSEMBLY__
 
 typedef __vector128 vector128;
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 73e461a3dfbb..2e0c565754aa 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -453,7 +453,7 @@ _GLOBAL(ret_from_kernel_thread)
         REST_NVGPRS(r1)
         mtlr    r14
         mr      r3,r15
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
         mr      r12,r14
 #endif
         blrl
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index 1123a4d8d8dd..7af6c4de044b 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -608,7 +608,7 @@ unsigned long __init arch_syscall_addr(int nr)
 }
 #endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_PPC64 */
 
-#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF != 2)
+#ifdef PPC64_ELF_ABI_v1
 char *arch_ftrace_match_adjust(char *str, const char *search)
 {
         if (str[0] == '.' && search[0] != '.')
@@ -616,4 +616,4 @@ char *arch_ftrace_match_adjust(char *str, const char *search)
         else
                 return str;
 }
-#endif /* defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF != 2) */
+#endif /* PPC64_ELF_ABI_v1 */
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 2d14774af6b4..064cd9397836 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -401,7 +401,7 @@ generic_secondary_common_init:
         ld      r12,CPU_SPEC_RESTORE(r23)
         cmpdi   0,r12,0
         beq     3f
-#if !defined(_CALL_ELF) || _CALL_ELF != 2
+#ifdef PPC64_ELF_ABI_v1
         ld      r12,0(r12)
 #endif
         mtctr   r12
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 7c053f281406..7d48e3baa38b 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -506,13 +506,11 @@ int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
 
         /* setup return addr to the jprobe handler routine */
         regs->nip = arch_deref_entry_point(jp->entry);
-#ifdef CONFIG_PPC64
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
         regs->gpr[12] = (unsigned long)jp->entry;
-#else
+#elif defined(PPC64_ELF_ABI_v1)
         regs->gpr[2] = (unsigned long)(((func_descr_t *)jp->entry)->toc);
 #endif
-#endif
 
         return 1;
 }
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index f28754c497e5..7a8519052b14 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -661,7 +661,7 @@ _GLOBAL(kexec_sequence)
 
 #ifndef CONFIG_PPC_BOOK3E
         /* clear out hardware hash page table and tlb */
-#if !defined(_CALL_ELF) || _CALL_ELF != 2
+#ifdef PPC64_ELF_ABI_v1
         ld      r12,0(r27)              /* deref function descriptor */
 #else
         mr      r12,r27
diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c
index 9ce9a25f58b5..f703f343358e 100644
--- a/arch/powerpc/kernel/module_64.c
+++ b/arch/powerpc/kernel/module_64.c
@@ -41,7 +41,7 @@
    this, and makes other things simpler.  Anton?
    --RR.  */
 
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
 
 /* An address is simply the address of the function. */
 typedef unsigned long func_desc_t;
@@ -132,7 +132,7 @@ static u32 ppc64_stub_insns[] = {
         /* Save current r2 value in magic place on the stack. */
         0xf8410000|R2_STACK_OFFSET,     /* std     r2,R2_STACK_OFFSET(r1) */
         0xe98b0020,                     /* ld      r12,32(r11) */
-#if !defined(_CALL_ELF) || _CALL_ELF != 2
+#ifdef PPC64_ELF_ABI_v1
         /* Set up new r2 from function descriptor */
         0xe84b0028,                     /* ld      r2,40(r11) */
 #endif
diff --git a/arch/powerpc/kvm/book3s_interrupts.S b/arch/powerpc/kvm/book3s_interrupts.S
index d044b8b7c69d..901e6fe00c39 100644
--- a/arch/powerpc/kvm/book3s_interrupts.S
+++ b/arch/powerpc/kvm/book3s_interrupts.S
@@ -25,7 +25,7 @@
 #include <asm/exception-64s.h>
 
 #if defined(CONFIG_PPC_BOOK3S_64)
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
 #define FUNC(name)              name
 #else
 #define FUNC(name)              GLUE(.,name)
diff --git a/arch/powerpc/kvm/book3s_rmhandlers.S b/arch/powerpc/kvm/book3s_rmhandlers.S
index 16c4d88ba27d..42a4b237df5f 100644
--- a/arch/powerpc/kvm/book3s_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_rmhandlers.S
@@ -36,7 +36,7 @@
 
 #if defined(CONFIG_PPC_BOOK3S_64)
 
-#if defined(_CALL_ELF) && _CALL_ELF == 2
+#ifdef PPC64_ELF_ABI_v2
 #define FUNC(name)              name
 #else
 #define FUNC(name)              GLUE(.,name)