Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
---
arch/powerpc/mm/hugetlbpage.c | 43 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 80f6d2ed551a..5c829a83a4cc 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -17,6 +17,8 @@
#include <linux/memblock.h>
#include <linux/bootmem.h>
#include <linux/moduleparam.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
@@ -618,6 +620,46 @@ void hugetlb_free_pgd_range(struct mmu_gather *tlb,
}
/*
+ * 64 bit book3s use generic follow_page_mask
+ */
+#ifdef CONFIG_PPC_BOOK3S_64
+
+struct page *follow_huge_pd(struct vm_area_struct *vma,
+ unsigned long address, hugepd_t hpd,
+ int flags, int pdshift)
+{
+ pte_t *ptep;
+ spinlock_t *ptl;
+ struct page *page = NULL;
+ unsigned long mask;
+ int shift = hugepd_shift(hpd);
+ struct mm_struct *mm = vma->vm_mm;
+
+retry:
+ ptl = &mm->page_table_lock;
+ spin_lock(ptl);
+
+ ptep = hugepte_offset(hpd, address, pdshift);
+ if (pte_present(*ptep)) {
+ mask = (1UL << shift) - 1;
+ page = pte_page(*ptep);
+ page += ((address & mask) >> PAGE_SHIFT);
+ if (flags & FOLL_GET)
+ get_page(page);
+ } else {
+ if (is_hugetlb_entry_migration(*ptep)) {
+ spin_unlock(ptl);
+ __migration_entry_wait(mm, ptep, ptl);
+ goto retry;
+ }
+ }
+ spin_unlock(ptl);
+ return page;
+}
+
+#else /* !CONFIG_PPC_BOOK3S_64 */
+
+/*
* We are holding mmap_sem, so a parallel huge page collapse cannot run.
* To prevent hugepage split, disable irq.
*/
@@ -672,6 +714,7 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address,
BUG();
return NULL;
}
+#endif
static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
unsigned long sz)
--
2.7.4
