From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
x86 overloads the page->index field to store a pointer to the mm_struct.
Rename this to pt_mm so it's visible to other users.
Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
arch/x86/mm/pgtable.c | 5 ++---
include/linux/mm_types.h | 2 +-
2 files changed, 3 insertions(+), 4 deletions(-)
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index ffc8c13c50e4..938dbcd46b97 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -114,13 +114,12 @@ static inline void pgd_list_del(pgd_t *pgd)
static void pgd_set_mm(pgd_t *pgd, struct mm_struct *mm)
{
- BUILD_BUG_ON(sizeof(virt_to_page(pgd)->index) < sizeof(mm));
- virt_to_page(pgd)->index = (pgoff_t)mm;
+ virt_to_page(pgd)->pt_mm = mm;
}
struct mm_struct *pgd_page_get_mm(struct page *page)
{
- return (struct mm_struct *)page->index;
+ return page->pt_mm;
}
static void pgd_ctor(struct mm_struct *mm, pgd_t *pgd)
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index e0e74e91f3e8..0e6117123737 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -134,7 +134,7 @@ struct page {
unsigned long _pt_pad_1; /* compound_head */
pgtable_t pmd_huge_pte; /* protected by page->ptl */
unsigned long _pt_pad_2; /* mapping */
- unsigned long _pt_pad_3;
+ struct mm_struct *pt_mm;
#if ALLOC_SPLIT_PTLOCKS
spinlock_t *ptl;
#else
--
2.17.0
