mm/rmap: Convert rmap_walk() to take a folio

This ripples all the way through to every calling and called function
from rmap.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Author: Matthew Wilcox (Oracle)

include/linux/ksm.h

@@ -51,7 +51,7 @@ static inline void ksm_exit(struct mm_struct *mm)
 struct page *ksm_might_need_to_copy(struct page *page,
 			struct vm_area_struct *vma, unsigned long address);
 
-void rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc);
+void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc);
 void folio_migrate_ksm(struct folio *newfolio, struct folio *folio);
 
 #else  /* !CONFIG_KSM */
@@ -78,7 +78,7 @@ static inline struct page *ksm_might_need_to_copy(struct page *page,
 	return page;
 }
 
-static inline void rmap_walk_ksm(struct page *page,
+static inline void rmap_walk_ksm(struct folio *folio,
 			struct rmap_walk_control *rwc)
 {
 }

include/linux/rmap.h

@@ -266,7 +266,6 @@ void remove_migration_ptes(struct folio *src, struct folio *dst, bool locked);
 /*
  * Called by memory-failure.c to kill processes.
  */
-struct anon_vma *page_lock_anon_vma_read(struct page *page);
 struct anon_vma *folio_lock_anon_vma_read(struct folio *folio);
 void page_unlock_anon_vma_read(struct anon_vma *anon_vma);
 int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);
@@ -286,15 +285,15 @@ struct rmap_walk_control {
 	 * Return false if page table scanning in rmap_walk should be stopped.
 	 * Otherwise, return true.
 	 */
-	bool (*rmap_one)(struct page *page, struct vm_area_struct *vma,
+	bool (*rmap_one)(struct folio *folio, struct vm_area_struct *vma,
 					unsigned long addr, void *arg);
-	int (*done)(struct page *page);
-	struct anon_vma *(*anon_lock)(struct page *page);
+	int (*done)(struct folio *folio);
+	struct anon_vma *(*anon_lock)(struct folio *folio);
 	bool (*invalid_vma)(struct vm_area_struct *vma, void *arg);
 };
 
-void rmap_walk(struct page *page, struct rmap_walk_control *rwc);
-void rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc);
+void rmap_walk(struct folio *folio, struct rmap_walk_control *rwc);
+void rmap_walk_locked(struct folio *folio, struct rmap_walk_control *rwc);
 
 #else	/* !CONFIG_MMU */
 

mm/damon/paddr.c

@@ -16,10 +16,10 @@
 #include "../internal.h"
 #include "prmtv-common.h"
 
-static bool __damon_pa_mkold(struct page *page, struct vm_area_struct *vma,
+static bool __damon_pa_mkold(struct folio *folio, struct vm_area_struct *vma,
 		unsigned long addr, void *arg)
 {
-	DEFINE_PAGE_VMA_WALK(pvmw, page, vma, addr, 0);
+	DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, addr, 0);
 
 	while (page_vma_mapped_walk(&pvmw)) {
 		addr = pvmw.address;
@@ -37,7 +37,7 @@ static void damon_pa_mkold(unsigned long paddr)
 	struct page *page = damon_get_page(PHYS_PFN(paddr));
 	struct rmap_walk_control rwc = {
 		.rmap_one = __damon_pa_mkold,
-		.anon_lock = page_lock_anon_vma_read,
+		.anon_lock = folio_lock_anon_vma_read,
 	};
 	bool need_lock;
 
@@ -54,7 +54,7 @@ static void damon_pa_mkold(unsigned long paddr)
 	if (need_lock && !folio_trylock(folio))
 		goto out;
 
-	rmap_walk(&folio->page, &rwc);
+	rmap_walk(folio, &rwc);
 
 	if (need_lock)
 		folio_unlock(folio);
@@ -87,10 +87,9 @@ struct damon_pa_access_chk_result {
 	bool accessed;
 };
 
-static bool __damon_pa_young(struct page *page, struct vm_area_struct *vma,
+static bool __damon_pa_young(struct folio *folio, struct vm_area_struct *vma,
 		unsigned long addr, void *arg)
 {
-	struct folio *folio = page_folio(page);
 	struct damon_pa_access_chk_result *result = arg;
 	DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, addr, 0);
 
@@ -133,7 +132,7 @@ static bool damon_pa_young(unsigned long paddr, unsigned long *page_sz)
 	struct rmap_walk_control rwc = {
 		.arg = &result,
 		.rmap_one = __damon_pa_young,
-		.anon_lock = page_lock_anon_vma_read,
+		.anon_lock = folio_lock_anon_vma_read,
 	};
 	bool need_lock;
 
@@ -156,7 +155,7 @@ static bool damon_pa_young(unsigned long paddr, unsigned long *page_sz)
 		return NULL;
 	}
 
-	rmap_walk(&folio->page, &rwc);
+	rmap_walk(folio, &rwc);
 
 	if (need_lock)
 		folio_unlock(folio);

mm/folio-compat.c

@@ -164,10 +164,3 @@ void putback_lru_page(struct page *page)
 {
 	folio_putback_lru(page_folio(page));
 }
-
-#ifdef CONFIG_MMU
-struct anon_vma *page_lock_anon_vma_read(struct page *page)
-{
-	return folio_lock_anon_vma_read(page_folio(page));
-}
-#endif

mm/huge_memory.c

@@ -2572,7 +2572,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 		 * The caller does not necessarily hold an mmap_lock that would
 		 * prevent the anon_vma disappearing so we first we take a
 		 * reference to it and then lock the anon_vma for write. This
-		 * is similar to page_lock_anon_vma_read except the write lock
+		 * is similar to folio_lock_anon_vma_read except the write lock
 		 * is taken to serialise against parallel split or collapse
 		 * operations.
 		 */

mm/ksm.c

@@ -2588,21 +2588,21 @@ struct page *ksm_might_need_to_copy(struct page *page,
 	return new_page;
 }
 
-void rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc)
+void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc)
 {
 	struct stable_node *stable_node;
 	struct rmap_item *rmap_item;
 	int search_new_forks = 0;
 
-	VM_BUG_ON_PAGE(!PageKsm(page), page);
+	VM_BUG_ON_FOLIO(!folio_test_ksm(folio), folio);
 
 	/*
 	 * Rely on the page lock to protect against concurrent modifications
 	 * to that page's node of the stable tree.
 	 */
-	VM_BUG_ON_PAGE(!PageLocked(page), page);
+	VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
 
-	stable_node = page_stable_node(page);
+	stable_node = folio_stable_node(folio);
 	if (!stable_node)
 		return;
 again:
@@ -2637,11 +2637,11 @@ void rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc)
 			if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
 				continue;
 
-			if (!rwc->rmap_one(page, vma, addr, rwc->arg)) {
+			if (!rwc->rmap_one(folio, vma, addr, rwc->arg)) {
 				anon_vma_unlock_read(anon_vma);
 				return;
 			}
-			if (rwc->done && rwc->done(page)) {
+			if (rwc->done && rwc->done(folio)) {
 				anon_vma_unlock_read(anon_vma);
 				return;
 			}

mm/migrate.c

@@ -171,13 +171,11 @@ void putback_movable_pages(struct list_head *l)
 /*
  * Restore a potential migration pte to a working pte entry
  */
-static bool remove_migration_pte(struct page *page, struct vm_area_struct *vma,
-				 unsigned long addr, void *old)
+static bool remove_migration_pte(struct folio *folio,
+		struct vm_area_struct *vma, unsigned long addr, void *old)
 {
-	struct folio *folio = page_folio(page);
 	DEFINE_FOLIO_VMA_WALK(pvmw, old, vma, addr, PVMW_SYNC | PVMW_MIGRATION);
 
-	VM_BUG_ON_PAGE(PageTail(page), page);
 	while (page_vma_mapped_walk(&pvmw)) {
 		pte_t pte;
 		swp_entry_t entry;
@@ -269,9 +267,9 @@ void remove_migration_ptes(struct folio *src, struct folio *dst, bool locked)
 	};
 
 	if (locked)
-		rmap_walk_locked(&dst->page, &rwc);
+		rmap_walk_locked(dst, &rwc);
 	else
-		rmap_walk(&dst->page, &rwc);
+		rmap_walk(dst, &rwc);
 }
 
 /*

mm/page_idle.c

@@ -46,11 +46,10 @@ static struct page *page_idle_get_page(unsigned long pfn)
 	return page;
 }
 
-static bool page_idle_clear_pte_refs_one(struct page *page,
+static bool page_idle_clear_pte_refs_one(struct folio *folio,
 					struct vm_area_struct *vma,
 					unsigned long addr, void *arg)
 {
-	struct folio *folio = page_folio(page);
 	DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, addr, 0);
 	bool referenced = false;
 
@@ -93,7 +92,7 @@ static void page_idle_clear_pte_refs(struct page *page)
 	 */
 	static const struct rmap_walk_control rwc = {
 		.rmap_one = page_idle_clear_pte_refs_one,
-		.anon_lock = page_lock_anon_vma_read,
+		.anon_lock = folio_lock_anon_vma_read,
 	};
 	bool need_lock;
 
@@ -104,7 +103,7 @@ static void page_idle_clear_pte_refs(struct page *page)
 	if (need_lock && !folio_trylock(folio))
 		return;
 
-	rmap_walk(&folio->page, (struct rmap_walk_control *)&rwc);
+	rmap_walk(folio, (struct rmap_walk_control *)&rwc);
 
 	if (need_lock)
 		folio_unlock(folio);