Commit 57761da4 authored by Sven Schnelle's avatar Sven Schnelle Committed by Heiko Carstens
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s390/vdso: move vdso mapping to its own function 



This is a preparation patch for adding vdso randomization to s390.
It adds a function vdso_size(), which will be used later in calculating
the STACK_TOP value. It also moves the vdso mapping into a new function
vdso_map(), to keep the code similar to other architectures.

Signed-off-by: default avatarSven Schnelle <svens@linux.ibm.com>
Reviewed-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
parent f2f47d0e

arch/s390/include/asm/processor.h

+1 −0
Original line number Original line Diff line number Diff line
@@ -83,6 +83,7 @@ void cpu_detect_mhz_feature(void); 
extern const struct seq_operations cpuinfo_op;

extern const struct seq_operations cpuinfo_op;

extern void execve_tail(void);

extern void execve_tail(void);

extern void __bpon(void);

extern void __bpon(void);

unsigned long vdso_size(void);





/*

/*

 * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.

 * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.

arch/s390/kernel/vdso.c

+19 −5
Original line number Original line Diff line number Diff line
@@ -160,10 +160,9 @@ int vdso_getcpu_init(void) 
}

}

early_initcall(vdso_getcpu_init); /* Must be called before SMP init */

early_initcall(vdso_getcpu_init); /* Must be called before SMP init */





int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)

static int map_vdso(unsigned long addr, unsigned long vdso_mapping_len)

{

{

	unsigned long vdso_text_len, vdso_mapping_len;

	unsigned long vvar_start, vdso_text_start, vdso_text_len;

	unsigned long vvar_start, vdso_text_start;

	struct vm_special_mapping *vdso_mapping;

	struct vm_special_mapping *vdso_mapping;

	struct mm_struct *mm = current->mm;

	struct mm_struct *mm = current->mm;

	struct vm_area_struct *vma;

	struct vm_area_struct *vma;
@@ -180,8 +179,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 
		vdso_text_len = vdso64_end - vdso64_start;

		vdso_text_len = vdso64_end - vdso64_start;

		vdso_mapping = &vdso64_mapping;

		vdso_mapping = &vdso64_mapping;

	}

	}

	vdso_mapping_len = vdso_text_len + VVAR_NR_PAGES * PAGE_SIZE;

	vvar_start = get_unmapped_area(NULL, addr, vdso_mapping_len, 0, 0);

	vvar_start = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0);

	rc = vvar_start;

	rc = vvar_start;

	if (IS_ERR_VALUE(vvar_start))

	if (IS_ERR_VALUE(vvar_start))

		goto out;

		goto out;
@@ -210,6 +208,22 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 
	return rc;

	return rc;

}

}





unsigned long vdso_size(void)

{

	unsigned long size = VVAR_NR_PAGES * PAGE_SIZE;



	if (is_compat_task())

		size += vdso32_end - vdso32_start;

	else

		size += vdso64_end - vdso64_start;

	return PAGE_ALIGN(size);

}



int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)

{

	return map_vdso(0, vdso_size());

}



static struct page ** __init vdso_setup_pages(void *start, void *end)

static struct page ** __init vdso_setup_pages(void *start, void *end)

{

{

	int pages = (end - start) >> PAGE_SHIFT;

	int pages = (end - start) >> PAGE_SHIFT;