[PATCH v5 06/33] mm: Convert ptlock_alloc() to use ptdescs

["Vishal Moola (Oracle)" <vishal.moola@xxxxxxxxx>]

This removes some direct accesses to struct page, working towards
splitting out struct ptdesc from struct page.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
---
 include/linux/mm.h | 6 +++---
 mm/memory.c        | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 1511faf0263c..39b0a4661e44 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2798,7 +2798,7 @@ static inline void pagetable_free(struct ptdesc *pt)
 #if USE_SPLIT_PTE_PTLOCKS
 #if ALLOC_SPLIT_PTLOCKS
 void __init ptlock_cache_init(void);
-extern bool ptlock_alloc(struct page *page);
+bool ptlock_alloc(struct ptdesc *ptdesc);
 extern void ptlock_free(struct page *page);
 
 static inline spinlock_t *ptlock_ptr(struct page *page)
@@ -2810,7 +2810,7 @@ static inline void ptlock_cache_init(void)
 {
 }
 
-static inline bool ptlock_alloc(struct page *page)
+static inline bool ptlock_alloc(struct ptdesc *ptdesc)
 {
        return true;
 }
@@ -2840,7 +2840,7 @@ static inline bool ptlock_init(struct page *page)
         * slab code uses page->slab_cache, which share storage with page->ptl.
         */
        VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page);
-       if (!ptlock_alloc(page))
+       if (!ptlock_alloc(page_ptdesc(page)))
                return false;
        spin_lock_init(ptlock_ptr(page));
        return true;
diff --git a/mm/memory.c b/mm/memory.c
index 80faf3e76232..2ff14f50c7b3 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -5920,14 +5920,14 @@ void __init ptlock_cache_init(void)
                        SLAB_PANIC, NULL);
 }
 
-bool ptlock_alloc(struct page *page)
+bool ptlock_alloc(struct ptdesc *ptdesc)
 {
        spinlock_t *ptl;
 
        ptl = kmem_cache_alloc(page_ptl_cachep, GFP_KERNEL);
        if (!ptl)
                return false;
-       page->ptl = ptl;
+       ptdesc->ptl = ptl;
        return true;
 }
 
-- 
2.40.1