mm/rmap: remove page_remove_rmap()

All callers are gone, let's remove it and some leftover traces.

Link: https://lkml.kernel.org/r/20231220224504.646757-33-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yin Fengwei <fengwei.yin@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/rmap.h

@@ -241,8 +241,6 @@ void folio_add_file_rmap_ptes(struct folio *, struct page *, int nr_pages,
 	folio_add_file_rmap_ptes(folio, page, 1, vma)
 void folio_add_file_rmap_pmd(struct folio *, struct page *,
 		struct vm_area_struct *);
-void page_remove_rmap(struct page *, struct vm_area_struct *,
-		bool compound);
 void folio_remove_rmap_ptes(struct folio *, struct page *, int nr_pages,
 		struct vm_area_struct *);
 #define folio_remove_rmap_pte(folio, page, vma) \
@@ -389,7 +387,7 @@ dup:
  *
  * This is similar to page_try_dup_anon_rmap(), however, not used during fork()
  * to duplicate a mapping, but instead to prepare for KSM or temporarily
- * unmapping a page (swap, migration) via page_remove_rmap().
+ * unmapping a page (swap, migration) via folio_remove_rmap_*().
  *
  * Marking the page shared can only fail if the page may be pinned; device
  * private pages cannot get pinned and consequently this function cannot fail.

mm/filemap.c

@@ -113,11 +113,11 @@
  *    ->i_pages lock		(try_to_unmap_one)
  *    ->lruvec->lru_lock	(follow_page->mark_page_accessed)
  *    ->lruvec->lru_lock	(check_pte_range->isolate_lru_page)
- *    ->private_lock		(page_remove_rmap->set_page_dirty)
+ *    ->private_lock		(folio_remove_rmap_pte->set_page_dirty)
- *    ->i_pages lock		(page_remove_rmap->set_page_dirty)
+ *    ->i_pages lock		(folio_remove_rmap_pte->set_page_dirty)
- *    bdi.wb->list_lock		(page_remove_rmap->set_page_dirty)
+ *    bdi.wb->list_lock		(folio_remove_rmap_pte->set_page_dirty)
- *    ->inode->i_lock		(page_remove_rmap->set_page_dirty)
+ *    ->inode->i_lock		(folio_remove_rmap_pte->set_page_dirty)
- *    ->memcg->move_lock	(page_remove_rmap->folio_memcg_lock)
+ *    ->memcg->move_lock	(folio_remove_rmap_pte->folio_memcg_lock)
  *    bdi.wb->list_lock		(zap_pte_range->set_page_dirty)
  *    ->inode->i_lock		(zap_pte_range->set_page_dirty)
  *    ->private_lock		(zap_pte_range->block_dirty_folio)

mm/internal.h

@@ -651,7 +651,7 @@ folio_within_vma(struct folio *folio, struct vm_area_struct *vma)
  * under page table lock for the pte/pmd being added or removed.
  *
  * mlock is usually called at the end of page_add_*_rmap(), munlock at
- * the end of page_remove_rmap(); but new anon folios are managed by
+ * the end of folio_remove_rmap_*(); but new anon folios are managed by
  * folio_add_lru_vma() calling mlock_new_folio().
  */
 void mlock_folio(struct folio *folio);

mm/memory-failure.c

@@ -2315,8 +2315,8 @@ try_again:
 	 * We use page flags to determine what action should be taken, but
 	 * the flags can be modified by the error containment action.  One
 	 * example is an mlocked page, where PG_mlocked is cleared by
-	 * page_remove_rmap() in try_to_unmap_one(). So to determine page status
+	 * folio_remove_rmap_*() in try_to_unmap_one(). So to determine page
-	 * correctly, we save a copy of the page flags at this time.
+	 * status correctly, we save a copy of the page flags at this time.
 	 */
 	page_flags = p->flags;
 

mm/rmap.c

@@ -470,7 +470,7 @@ void __init anon_vma_init(void)
 /*
  * Getting a lock on a stable anon_vma from a page off the LRU is tricky!
  *
- * Since there is no serialization what so ever against page_remove_rmap()
+ * Since there is no serialization what so ever against folio_remove_rmap_*()
  * the best this function can do is return a refcount increased anon_vma
  * that might have been relevant to this page.
  *
@@ -487,7 +487,7 @@ void __init anon_vma_init(void)
  * [ something equivalent to page_mapped_in_vma() ].
  *
  * Since anon_vma's slab is SLAB_TYPESAFE_BY_RCU and we know from
- * page_remove_rmap() that the anon_vma pointer from page->mapping is valid
+ * folio_remove_rmap_*() that the anon_vma pointer from page->mapping is valid
  * if there is a mapcount, we can dereference the anon_vma after observing
  * those.
  *
@@ -1498,25 +1498,6 @@ void folio_add_file_rmap_pmd(struct folio *folio, struct page *page,
 #endif
 }
 
-/**
- * page_remove_rmap - take down pte mapping from a page
- * @page:	page to remove mapping from
- * @vma:	the vm area from which the mapping is removed
- * @compound:	uncharge the page as compound or small page
- *
- * The caller needs to hold the pte lock.
- */
-void page_remove_rmap(struct page *page, struct vm_area_struct *vma,
-		bool compound)
-{
-	struct folio *folio = page_folio(page);
-
-	if (likely(!compound))
-		folio_remove_rmap_pte(folio, page, vma);
-	else
-		folio_remove_rmap_pmd(folio, page, vma);
-}
-
 static __always_inline void __folio_remove_rmap(struct folio *folio,
 		struct page *page, int nr_pages, struct vm_area_struct *vma,
 		enum rmap_level level)