Commit 02e0409a authored by Nathan Lynch's avatar Nathan Lynch Committed by Russell King
Browse files

ARM: 8154/1: use _install_special_mapping for sigpage 



_install_special_mapping allows the VMA to be identifed in
/proc/pid/maps without the use of arch_vma_name, providing a
slight net reduction in object size:

  text    data     bss     dec     hex filename
  2996      96     144    3236     ca4 arch/arm/kernel/process.o (before)
  2956     104     144    3204     c84 arch/arm/kernel/process.o (after)

Signed-off-by: default avatarNathan Lynch <nathan_lynch@mentor.com>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 75c34906

arch/arm/kernel/process.c

+16 −8
Original line number Diff line number Diff line
@@ -472,19 +472,23 @@ int in_gate_area_no_mm(unsigned long addr) 


const char *arch_vma_name(struct vm_area_struct *vma)

{

	return is_gate_vma(vma) ? "[vectors]" :

		(vma->vm_mm && vma->vm_start == vma->vm_mm->context.sigpage) ?

		 "[sigpage]" : NULL;

	return is_gate_vma(vma) ? "[vectors]" : NULL;

}



static struct page *signal_page;

extern struct page *get_signal_page(void);



static const struct vm_special_mapping sigpage_mapping = {

	.name = "[sigpage]",

	.pages = &signal_page,

};



int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)

{

	struct mm_struct *mm = current->mm;

	struct vm_area_struct *vma;

	unsigned long addr;

	int ret;

	int ret = 0;



	if (!signal_page)

		signal_page = get_signal_page();
@@ -498,11 +502,15 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 
		goto up_fail;

	}



	ret = install_special_mapping(mm, addr, PAGE_SIZE,

	vma = _install_special_mapping(mm, addr, PAGE_SIZE,

		VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,

		&signal_page);

		&sigpage_mapping);



	if (IS_ERR(vma)) {

		ret = PTR_ERR(vma);

		goto up_fail;

	}



	if (ret == 0)

	mm->context.sigpage = addr;



 up_fail:

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