Commit caff3a2c authored Aug 12, 2008 by Gerald Schaefer Committed by Linus Torvalds Aug 12, 2008

hugetlb: call arch_prepare_hugepage() for surplus pages

The s390 software large page emulation implements shared page tables by
using page->index of the first tail page from a compound large page to
store page table information. This is set up in arch_prepare_hugepage(),
which is called from alloc_fresh_huge_page_node().

A similar call to arch_prepare_hugepage() is missing for surplus large
pages that are allocated in alloc_buddy_huge_page(), which breaks the
software emulation mode for (surplus) large pages on s390. This patch
adds the missing call to arch_prepare_hugepage(). It will have no effect
on other architectures where arch_prepare_hugepage() is a nop.

Also, use the correct order in the error path in alloc_fresh_huge_page_node().

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Acked-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 02eb7eeb

mm/hugetlb.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -565,7 +565,7 @@ static struct page alloc_fresh_huge_page_node(struct hstate h, int nid)
		huge_page_order(h));
		if (page) {
		if (arch_prepare_hugepage(page)) {
		__free_pages(page, HUGETLB_PAGE_ORDER);
		__free_pages(page, huge_page_order(h));
		return NULL;
		}
		prep_new_huge_page(h, page, nid);
		@@ -665,6 +665,11 @@ static struct page alloc_buddy_huge_page(struct hstate h,
		__GFP_REPEAT\|__GFP_NOWARN,
		huge_page_order(h));

		if (page && arch_prepare_hugepage(page)) {
		__free_pages(page, huge_page_order(h));
		return NULL;
		}

		spin_lock(&hugetlb_lock);
		if (page) {
		/*