[074/262] mm: drop first_index/last_index in zap_details

Commit Message

Andrew Morton Nov. 5, 2021, 8:38 p.m. UTC

From: Peter Xu <[e-mail]>
Subject: mm: drop first_index/last_index in zap_details

The first_index/last_index parameters in zap_details are actually only
used in unmap_mapping_range_tree().  At the meantime, this function is
only called by unmap_mapping_pages() once.  Instead of passing these two
variables through the whole stack of page zapping code, remove them from
zap_details and let them simply be parameters of
unmap_mapping_range_tree(), which is inlined.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Peter Xu <[e-mail]>
Reviewed-by: Alistair Popple <[e-mail]>
Reviewed-by: David Hildenbrand <[e-mail]>
Reviewed-by: Liam Howlett <[e-mail]>
Acked-by: Hugh Dickins <[e-mail]>
Cc: Andrea Arcangeli <[e-mail]>
Cc: Axel Rasmussen <[e-mail]>
Cc: Jerome Glisse <[e-mail]>
Cc: "Kirill A . Shutemov" <[e-mail]>
Cc: Matthew Wilcox <[e-mail]>
Cc: Miaohe Lin <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: Yang Shi <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 include/linux/mm.h |    2 --
 mm/memory.c        |   31 ++++++++++++++++++-------------
 2 files changed, 18 insertions(+), 15 deletions(-)

Patch

--- a/include/linux/mm.h~mm-drop-first_index-last_index-in-zap_details
+++ a/include/linux/mm.h
@@ -1688,8 +1688,6 @@  extern void user_shm_unlock(size_t, stru
  */
 struct zap_details {
 	struct address_space *check_mapping;	/* Check page->mapping if set */
-	pgoff_t	first_index;			/* Lowest page->index to unmap */
-	pgoff_t last_index;			/* Highest page->index to unmap */
 	struct page *single_page;		/* Locked page to be unmapped */
 };
 
--- a/mm/memory.c~mm-drop-first_index-last_index-in-zap_details
+++ a/mm/memory.c
@@ -3325,20 +3325,20 @@  static void unmap_mapping_range_vma(stru
 }
 
 static inline void unmap_mapping_range_tree(struct rb_root_cached *root,
+					    pgoff_t first_index,
+					    pgoff_t last_index,
 					    struct zap_details *details)
 {
 	struct vm_area_struct *vma;
 	pgoff_t vba, vea, zba, zea;
 
-	vma_interval_tree_foreach(vma, root,
-			details->first_index, details->last_index) {
-
+	vma_interval_tree_foreach(vma, root, first_index, last_index) {
 		vba = vma->vm_pgoff;
 		vea = vba + vma_pages(vma) - 1;
-		zba = details->first_index;
+		zba = first_index;
 		if (zba < vba)
 			zba = vba;
-		zea = details->last_index;
+		zea = last_index;
 		if (zea > vea)
 			zea = vea;
 
@@ -3364,18 +3364,22 @@  void unmap_mapping_page(struct page *pag
 {
 	struct address_space *mapping = page->mapping;
 	struct zap_details details = { };
+	pgoff_t	first_index;
+	pgoff_t	last_index;
 
 	VM_BUG_ON(!PageLocked(page));
 	VM_BUG_ON(PageTail(page));
 
+	first_index = page->index;
+	last_index = page->index + thp_nr_pages(page) - 1;
+
 	details.check_mapping = mapping;
-	details.first_index = page->index;
-	details.last_index = page->index + thp_nr_pages(page) - 1;
 	details.single_page = page;
 
 	i_mmap_lock_write(mapping);
 	if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap.rb_root)))
-		unmap_mapping_range_tree(&mapping->i_mmap, &details);
+		unmap_mapping_range_tree(&mapping->i_mmap, first_index,
+					 last_index, &details);
 	i_mmap_unlock_write(mapping);
 }
 
@@ -3395,16 +3399,17 @@  void unmap_mapping_pages(struct address_
 		pgoff_t nr, bool even_cows)
 {
 	struct zap_details details = { };
+	pgoff_t	first_index = start;
+	pgoff_t	last_index = start + nr - 1;
 
 	details.check_mapping = even_cows ? NULL : mapping;
-	details.first_index = start;
-	details.last_index = start + nr - 1;
-	if (details.last_index < details.first_index)
-		details.last_index = ULONG_MAX;
+	if (last_index < first_index)
+		last_index = ULONG_MAX;
 
 	i_mmap_lock_write(mapping);
 	if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap.rb_root)))
-		unmap_mapping_range_tree(&mapping->i_mmap, &details);
+		unmap_mapping_range_tree(&mapping->i_mmap, first_index,
+					 last_index, &details);
 	i_mmap_unlock_write(mapping);
 }
 EXPORT_SYMBOL_GPL(unmap_mapping_pages);