[PATCH] arm/mm: fix compiler warning in pmdp_invalidate() (in -next)

[Andre Przywara]

Commit ff61d185f4e7 ("mm: convert p[te|md]_mknonnuma and remaining
page table manipulations") removed a check in
mm/pgtable-generic.c:pmdp_invalidate(), which leaves the
pmd_mknotpresent macro the only user of the entry variable.
For ARM/LPAE we use a constant 0 without referencing the argument to
mark this condition, so the entry variable is no longer used here:

mm/pgtable-generic.c: In function 'pmdp_invalidate':
mm/pgtable-generic.c:195:8: warning: unused variable 'entry' [-Wunused-variable]
  pmd_t entry = *pmdp;
        ^

Replace the ARM macro implementation with a static inline function to
get rid of this warning.

Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---
 arch/arm/include/asm/pgtable-3level.h |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 370684d..0e51fbe 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -259,7 +259,10 @@ PMD_BIT_FUNC(mkyoung,   |= PMD_SECT_AF);
 #define mk_pmd(page,prot)	pfn_pmd(page_to_pfn(page),prot)
 
 /* represent a notpresent pmd by zero, this is used by pmdp_invalidate */
-#define pmd_mknotpresent(pmd)	(__pmd(0))
+static inline pmd_t pmd_mknotpresent(pmd_t pmd)
+{
+	return 0;
+}
 
 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
 {
-- 
1.7.9.5