powerpc/mm: Don't update page->_mapcount for hugetlb tail pages

The changes to increment _mapcount was added w.r.t THP change
3526741f0964c88bc2ce511e1078359052bf225b. Later this was fixed
to to handle the hugetlb case in 44518d2b32646e37b4b7a0813bbbe98dc21c7f8f
Instead of backporting 44518, we can remove the _mapcount update since
we don't support THP for kvm host yet.

Fixes: bz# 108558
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

1 files changed, 0 insertions, 10 deletions

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 77fdd2cef33b5a..4d10493afffc0a 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -809,16 +809,6 @@ int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
 		return 0;
 	}
 
-	/*
-	 * Any tail page need their mapcount reference taken before we
-	 * return.
-	 */
-	while (refs--) {
-		if (PageTail(tail))
-			get_huge_page_tail(tail);
-		tail++;
-	}
-
 	return 1;
 }