mm: remove mlock_vma_page()

All callers now have a folio and can call mlock_vma_folio().  Update the
documentation to refer to mlock_vma_folio().

Link: https://lkml.kernel.org/r/20230116192827.2146732-3-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Documentation/mm/unevictable-lru.rst

@@ -311,7 +311,7 @@ do end up getting faulted into this VM_LOCKED VMA, they will be handled in the
 fault path - which is also how mlock2()'s MLOCK_ONFAULT areas are handled.
 
 For each PTE (or PMD) being faulted into a VMA, the page add rmap function
-calls mlock_vma_page(), which calls mlock_folio() when the VMA is VM_LOCKED
+calls mlock_vma_folio(), which calls mlock_folio() when the VMA is VM_LOCKED
 (unless it is a PTE mapping of a part of a transparent huge page).  Or when
 it is a newly allocated anonymous page, folio_add_lru_vma() calls
 mlock_new_folio() instead: similar to mlock_folio(), but can make better
@@ -413,7 +413,7 @@ However, since mlock_vma_pages_range() starts by setting VM_LOCKED on a VMA,
 before mlocking any pages already present, if one of those pages were migrated
 before mlock_pte_range() reached it, it would get counted twice in mlock_count.
 To prevent that, mlock_vma_pages_range() temporarily marks the VMA as VM_IO,
-so that mlock_vma_page() will skip it.
+so that mlock_vma_folio() will skip it.
 
 To complete page migration, we place the old and new pages back onto the LRU
 afterwards.  The "unneeded" page - old page on success, new page on failure -
@@ -552,6 +552,6 @@ and node unevictable list.
 
 rmap's folio_referenced_one(), called via vmscan's shrink_active_list() or
 shrink_page_list(), and rmap's try_to_unmap_one() called via shrink_page_list(),
-check for (3) pages still mapped into VM_LOCKED VMAs, and call mlock_vma_page()
+check for (3) pages still mapped into VM_LOCKED VMAs, and call mlock_vma_folio()
 to correct them.  Such pages are culled to the unevictable list when released
 by the shrinker.

mm/internal.h

@@ -518,7 +518,7 @@ extern long faultin_vma_page_range(struct vm_area_struct *vma,
 extern int mlock_future_check(struct mm_struct *mm, unsigned long flags,
 			      unsigned long len);
 /*
- * mlock_vma_page() and munlock_vma_page():
+ * mlock_vma_folio() and munlock_vma_folio():
  * should be called with vma's mmap_lock held for read or write,
  * under page table lock for the pte/pmd being added or removed.
  *
@@ -547,12 +547,6 @@ static inline void mlock_vma_folio(struct folio *folio,
 		mlock_folio(folio);
 }
 
-static inline void mlock_vma_page(struct page *page,
-			struct vm_area_struct *vma, bool compound)
-{
-	mlock_vma_folio(page_folio(page), vma, compound);
-}
-
 void munlock_folio(struct folio *folio);
 
 static inline void munlock_vma_folio(struct folio *folio,
@@ -656,8 +650,6 @@ static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf,
 }
 #else /* !CONFIG_MMU */
 static inline void unmap_mapping_folio(struct folio *folio) { }
-static inline void mlock_vma_page(struct page *page,
-			struct vm_area_struct *vma, bool compound) { }
 static inline void munlock_vma_page(struct page *page,
 			struct vm_area_struct *vma, bool compound) { }
 static inline void mlock_new_folio(struct folio *folio) { }

mm/mlock.c

@@ -370,9 +370,9 @@ static void mlock_vma_pages_range(struct vm_area_struct *vma,
 	/*
 	 * There is a slight chance that concurrent page migration,
 	 * or page reclaim finding a page of this now-VM_LOCKED vma,
-	 * will call mlock_vma_page() and raise page's mlock_count:
+	 * will call mlock_vma_folio() and raise page's mlock_count:
 	 * double counting, leaving the page unevictable indefinitely.
-	 * Communicate this danger to mlock_vma_page() with VM_IO,
+	 * Communicate this danger to mlock_vma_folio() with VM_IO,
 	 * which is a VM_SPECIAL flag not allowed on VM_LOCKED vmas.
 	 * mmap_lock is held in write mode here, so this weird
 	 * combination should not be visible to other mmap_lock users;

mm/rmap.c

@@ -1260,7 +1260,7 @@ void page_add_anon_rmap(struct page *page, struct vm_area_struct *vma,
 			__page_check_anon_rmap(page, vma, address);
 	}
 
-	mlock_vma_page(page, vma, compound);
+	mlock_vma_folio(folio, vma, compound);
 }
 
 /**
@@ -1351,7 +1351,7 @@ void page_add_file_rmap(struct page *page, struct vm_area_struct *vma,
 	if (nr)
 		__lruvec_stat_mod_folio(folio, NR_FILE_MAPPED, nr);
 
-	mlock_vma_page(page, vma, compound);
+	mlock_vma_folio(folio, vma, compound);
 }
 
 /**