unicore32: switch to gate_vma straight copy of arm patch Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/arch/unicore32/include/asm/elf.h b/arch/unicore32/include/asm/elf.h
index 829042d..eeba258 100644
--- a/arch/unicore32/include/asm/elf.h
+++ b/arch/unicore32/include/asm/elf.h

@@ -87,8 +87,4 @@
 extern unsigned long arch_randomize_brk(struct mm_struct *mm);
 #define arch_randomize_brk arch_randomize_brk
 
-extern int vectors_user_mapping(void);
-#define arch_setup_additional_pages(bprm, uses_interp) vectors_user_mapping()
-#define ARCH_HAS_SETUP_ADDITIONAL_PAGES
-
 #endif

diff --git a/arch/unicore32/include/asm/mmu_context.h b/arch/unicore32/include/asm/mmu_context.h
index 1cb5220..8c25da9 100644
--- a/arch/unicore32/include/asm/mmu_context.h
+++ b/arch/unicore32/include/asm/mmu_context.h

@@ -20,6 +20,7 @@
 
 #include <asm/cacheflush.h>
 #include <asm/cpu-single.h>
+#include <asm-generic/mm_hooks.h>
 
 #define init_new_context(tsk, mm)	0
 
@@ -58,29 +59,6 @@
 #define deactivate_mm(tsk, mm)	do { } while (0)
 #define activate_mm(prev, next)	switch_mm(prev, next, NULL)
 
-/*
- * We are inserting a "fake" vma for the user-accessible vector page so
- * gdb and friends can get to it through ptrace and /proc/<pid>/mem.
- * But we also want to remove it before the generic code gets to see it
- * during process exit or the unmapping of it would  cause total havoc.
- * (the macro is used as remove_vma() is static to mm/mmap.c)
- */
-#define arch_exit_mmap(mm) \
-do { \
-	struct vm_area_struct *high_vma = find_vma(mm, 0xffff0000); \
-	if (high_vma) { \
-		BUG_ON(high_vma->vm_next);  /* it should be last */ \
-		if (high_vma->vm_prev) \
-			high_vma->vm_prev->vm_next = NULL; \
-		else \
-			mm->mmap = NULL; \
-		rb_erase(&high_vma->vm_rb, &mm->mm_rb); \
-		vmacache_invalidate(mm); \
-		mm->map_count--; \
-		remove_vma(high_vma); \
-	} \
-} while (0)
-
 static inline void arch_dup_mmap(struct mm_struct *oldmm,
 				 struct mm_struct *mm)
 {
@@ -96,5 +74,4 @@
 				     struct vm_area_struct *vma)
 {
 }
-
 #endif

diff --git a/arch/unicore32/include/asm/page.h b/arch/unicore32/include/asm/page.h
index 594b322..e79da8b 100644
--- a/arch/unicore32/include/asm/page.h
+++ b/arch/unicore32/include/asm/page.h

@@ -28,6 +28,8 @@
 #define clear_user_page(page, vaddr, pg)	clear_page(page)
 #define copy_user_page(to, from, vaddr, pg)	copy_page(to, from)
 
+#define __HAVE_ARCH_GATE_AREA 1
+
 #undef STRICT_MM_TYPECHECKS
 
 #ifdef STRICT_MM_TYPECHECKS

diff --git a/arch/unicore32/kernel/process.c b/arch/unicore32/kernel/process.c
index b008e99..2c0cee1 100644
--- a/arch/unicore32/kernel/process.c
+++ b/arch/unicore32/kernel/process.c

@@ -308,21 +308,39 @@
 
 /*
  * The vectors page is always readable from user space for the
- * atomic helpers and the signal restart code.  Let's declare a mapping
- * for it so it is visible through ptrace and /proc/<pid>/mem.
+ * atomic helpers and the signal restart code. Insert it into the
+ * gate_vma so that it is visible through ptrace and /proc/<pid>/mem.
  */
+static struct vm_area_struct gate_vma;
 
-int vectors_user_mapping(void)
+static int __init gate_vma_init(void)
 {
-	struct mm_struct *mm = current->mm;
-	return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
-				       VM_READ | VM_EXEC |
-				       VM_MAYREAD | VM_MAYEXEC |
-				       VM_DONTEXPAND | VM_DONTDUMP,
-				       NULL);
+	gate_vma.vm_start	= 0xffff0000;
+	gate_vma.vm_end		= 0xffff0000 + PAGE_SIZE;
+	gate_vma.vm_page_prot	= PAGE_READONLY_EXEC;
+	gate_vma.vm_flags	= VM_READ | VM_EXEC |
+				  VM_MAYREAD | VM_MAYEXEC |
+				  VM_DONTEXPAND | VM_DONTDUMP;
+	return 0;
+}
+arch_initcall(gate_vma_init);
+
+struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
+{
+	return &gate_vma;
+}
+
+int in_gate_area(struct mm_struct *mm, unsigned long addr)
+{
+	return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
+}
+
+int in_gate_area_no_mm(unsigned long addr)
+{
+	return in_gate_area(NULL, addr);
 }
 
 const char *arch_vma_name(struct vm_area_struct *vma)
 {
-	return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
+	return (vma == &gate_vma) ? "[vectors]" : NULL;
 }