FROMLIST: mm: introduce __lru_cache_add_active_or_unevictable

The speculative page fault handler which is run without holding the
mmap_sem is calling lru_cache_add_active_or_unevictable() but the vm_flags
is not guaranteed to remain constant.
Introducing __lru_cache_add_active_or_unevictable() which has the vma flags
value parameter instead of the vma pointer.

Change-Id: I68decbe0f80847403127c45c97565e47512532e9
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Link: https://lore.kernel.org/lkml/1523975611-15978-15-git-send-email-ldufour@linux.vnet.ibm.com/
Bug: 161210518
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
diff --git a/mm/memory.c b/mm/memory.c
index 733ce08..eca5654 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2947,7 +2947,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf)
 		 */
 		ptep_clear_flush_notify(vma, vmf->address, vmf->pte);
 		page_add_new_anon_rmap(new_page, vma, vmf->address, false);
-		lru_cache_add_inactive_or_unevictable(new_page, vma);
+		__lru_cache_add_inactive_or_unevictable(new_page, vmf->vma_flags);
 		/*
 		 * We call the notify macro here because, when using secondary
 		 * mmu page tables (such as kvm shadow page tables), we want the
@@ -3489,7 +3489,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
 	/* ksm created a completely new copy */
 	if (unlikely(page != swapcache && swapcache)) {
 		page_add_new_anon_rmap(page, vma, vmf->address, false);
-		lru_cache_add_inactive_or_unevictable(page, vma);
+		__lru_cache_add_inactive_or_unevictable(page, vmf->vma_flags);
 	} else {
 		do_page_add_anon_rmap(page, vma, vmf->address, exclusive);
 	}
@@ -3639,7 +3639,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
 
 	inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES);
 	page_add_new_anon_rmap(page, vma, vmf->address, false);
-	lru_cache_add_inactive_or_unevictable(page, vma);
+	__lru_cache_add_inactive_or_unevictable(page, vmf->vma_flags);
 setpte:
 	set_pte_at(vma->vm_mm, vmf->address, vmf->pte, entry);
 
@@ -3901,7 +3901,7 @@ vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct page *page)
 	if (write && !(vmf->vma_flags & VM_SHARED)) {
 		inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES);
 		page_add_new_anon_rmap(page, vma, vmf->address, false);
-		lru_cache_add_inactive_or_unevictable(page, vma);
+		__lru_cache_add_inactive_or_unevictable(page, vmf->vma_flags);
 	} else {
 		inc_mm_counter_fast(vma->vm_mm, mm_counter_file(page));
 		page_add_file_rmap(page, false);
diff --git a/mm/swap.c b/mm/swap.c
index 47a4768..d160a078 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -483,14 +483,14 @@ EXPORT_SYMBOL(lru_cache_add);
  * Place @page on the inactive or unevictable LRU list, depending on its
  * evictability.
  */
-void lru_cache_add_inactive_or_unevictable(struct page *page,
-					 struct vm_area_struct *vma)
+void __lru_cache_add_inactive_or_unevictable(struct page *page,
+					 unsigned long vma_flags)
 {
 	bool unevictable;
 
 	VM_BUG_ON_PAGE(PageLRU(page), page);
 
-	unevictable = (vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) == VM_LOCKED;
+	unevictable = (vma_flags & (VM_LOCKED | VM_SPECIAL)) == VM_LOCKED;
 	if (unlikely(unevictable) && !TestSetPageMlocked(page)) {
 		int nr_pages = thp_nr_pages(page);
 		/*