mm: convert lock_page_or_retry() to folio_lock_or_retry()

Remove a call to compound_head() in each of the two callers.

Link: https://lkml.kernel.org/r/20220902194653.1739778-58-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/pagemap.h

@@ -989,19 +989,16 @@ static inline int lock_page_killable(struct page *page)
 }
 
 /*
- * lock_page_or_retry - Lock the page, unless this would block and the
+ * folio_lock_or_retry - Lock the folio, unless this would block and the
  * caller indicated that it can handle a retry.
  *
  * Return value and mmap_lock implications depend on flags; see
  * __folio_lock_or_retry().
  */
-static inline bool lock_page_or_retry(struct page *page, struct mm_struct *mm,
-				     unsigned int flags)
+static inline bool folio_lock_or_retry(struct folio *folio,
+		struct mm_struct *mm, unsigned int flags)
 {
-	struct folio *folio;
 	might_sleep();
-
-	folio = page_folio(page);
 	return folio_trylock(folio) || __folio_lock_or_retry(folio, mm, flags);
 }
 

mm/memory.c

@@ -3618,11 +3618,11 @@ EXPORT_SYMBOL(unmap_mapping_range);
  */
 static vm_fault_t remove_device_exclusive_entry(struct vm_fault *vmf)
 {
-	struct page *page = vmf->page;
+	struct folio *folio = page_folio(vmf->page);
 	struct vm_area_struct *vma = vmf->vma;
 	struct mmu_notifier_range range;
 
-	if (!lock_page_or_retry(page, vma->vm_mm, vmf->flags))
+	if (!folio_lock_or_retry(folio, vma->vm_mm, vmf->flags))
 		return VM_FAULT_RETRY;
 	mmu_notifier_range_init_owner(&range, MMU_NOTIFY_EXCLUSIVE, 0, vma,
 				vma->vm_mm, vmf->address & PAGE_MASK,
@@ -3632,10 +3632,10 @@ static vm_fault_t remove_device_exclusive_entry(struct vm_fault *vmf)
 	vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address,
 				&vmf->ptl);
 	if (likely(pte_same(*vmf->pte, vmf->orig_pte)))
-		restore_exclusive_pte(vma, page, vmf->address, vmf->pte);
+		restore_exclusive_pte(vma, vmf->page, vmf->address, vmf->pte);
 
 	pte_unmap_unlock(vmf->pte, vmf->ptl);
-	unlock_page(page);
+	folio_unlock(folio);
 
 	mmu_notifier_invalidate_range_end(&range);
 	return 0;
@@ -3835,7 +3835,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
 		goto out_release;
 	}
 
-	locked = lock_page_or_retry(page, vma->vm_mm, vmf->flags);
+	locked = folio_lock_or_retry(folio, vma->vm_mm, vmf->flags);
 
 	if (!locked) {
 		ret |= VM_FAULT_RETRY;