arm64,ia64,ppc,s390,sh,tile,um,x86,mm: remove default gate area

The core mm code will provide a default gate area based on
FIXADDR_USER_START and FIXADDR_USER_END if
!defined(__HAVE_ARCH_GATE_AREA) && defined(AT_SYSINFO_EHDR).

This default is only useful for ia64.  arm64, ppc, s390, sh, tile, 64-bit
UML, and x86_32 have their own code just to disable it.  arm, 32-bit UML,
and x86_64 have gate areas, but they have their own implementations.

This gets rid of the default and moves the code into ia64.

This should save some code on architectures without a gate area: it's now
possible to inline the gate_area functions in the default case.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [in principle]
Acked-by: Richard Weinberger <richard@nod.at> [for um]
Acked-by: Will Deacon <will.deacon@arm.com> [for arm64]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5 files changed, 3 insertions, 35 deletions

diff --git a/arch/x86/include/asm/page.h b/arch/x86/include/asm/page.h
index 775873d3be55..802dde30c928 100644
--- a/arch/x86/include/asm/page.h
+++ b/arch/x86/include/asm/page.h
@@ -70,7 +70,6 @@ extern bool __virt_addr_valid(unsigned long kaddr);
 #include <asm-generic/memory_model.h>
 #include <asm-generic/getorder.h>
 
-#define __HAVE_ARCH_GATE_AREA 1
 #define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
 
 #endif  /* __KERNEL__ */
diff --git a/arch/x86/include/asm/page_64.h b/arch/x86/include/asm/page_64.h
index 0f1ddee6a0ce..f408caf73430 100644
--- a/arch/x86/include/asm/page_64.h
+++ b/arch/x86/include/asm/page_64.h
@@ -39,4 +39,6 @@ void copy_page(void *to, void *from);
 
 #endif  /* !__ASSEMBLY__ */
 
+#define __HAVE_ARCH_GATE_AREA 1
+
 #endif /* _ASM_X86_PAGE_64_H */
diff --git a/arch/x86/um/asm/elf.h b/arch/x86/um/asm/elf.h
index 0feee2fd5077..25a1022dd793 100644
--- a/arch/x86/um/asm/elf.h
+++ b/arch/x86/um/asm/elf.h
@@ -216,6 +216,5 @@ extern long elf_aux_hwcap;
 #define ELF_HWCAP (elf_aux_hwcap)
 
 #define SET_PERSONALITY(ex) do ; while(0)
-#define __HAVE_ARCH_GATE_AREA 1
 
 #endif
diff --git a/arch/x86/um/mem_64.c b/arch/x86/um/mem_64.c
index c6492e75797b..f8fecaddcc0d 100644
--- a/arch/x86/um/mem_64.c
+++ b/arch/x86/um/mem_64.c
@@ -9,18 +9,3 @@ const char *arch_vma_name(struct vm_area_struct *vma)
 
         return NULL;
 }
-
-struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
-{
-        return NULL;
-}
-
-int in_gate_area(struct mm_struct *mm, unsigned long addr)
-{
-        return 0;
-}
-
-int in_gate_area_no_mm(unsigned long addr)
-{
-        return 0;
-}
diff --git a/arch/x86/vdso/vdso32-setup.c b/arch/x86/vdso/vdso32-setup.c
index e4f7781ee162..e904c270573b 100644
--- a/arch/x86/vdso/vdso32-setup.c
+++ b/arch/x86/vdso/vdso32-setup.c
@@ -115,23 +115,6 @@ static __init int ia32_binfmt_init(void)
         return 0;
 }
 __initcall(ia32_binfmt_init);
-#endif
-
-#else  /* CONFIG_X86_32 */
-
-struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
-{
-        return NULL;
-}
-
-int in_gate_area(struct mm_struct *mm, unsigned long addr)
-{
-        return 0;
-}
-
-int in_gate_area_no_mm(unsigned long addr)
-{
-        return 0;
-}
+#endif /* CONFIG_SYSCTL */
 
 #endif  /* CONFIG_X86_64 */