[PATCH v1 9/9] mm: Use unmap_desc struct for freeing page tables.

[Liam R. Howlett]

Pass through the unmap_desc to free_pgtables() because it almost has
everything necessary and is already on the stack.

Updates testing code as necessary.

No functional changes intended.

Signed-off-by: Liam R. Howlett <Liam.Howlett at oracle.com>
---
 mm/internal.h                    |  5 +----
 mm/memory.c                      | 21 ++++++++++-----------
 mm/mmap.c                        |  6 +++---
 mm/vma.c                         |  7 ++-----
 tools/testing/vma/vma_internal.h | 11 ++---------
 5 files changed, 18 insertions(+), 32 deletions(-)

diff --git a/mm/internal.h b/mm/internal.h
index 1239944f2830a..f22329967e908 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -445,10 +445,7 @@ bool __folio_end_writeback(struct folio *folio);
 void deactivate_file_folio(struct folio *folio);
 void folio_activate(struct folio *folio);
 
-void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
-		   struct vm_area_struct *start_vma, unsigned long floor,
-		   unsigned long ceiling, unsigned long tree_max,
-		   bool mm_wr_locked);
+void free_pgtables(struct mmu_gather *tlb, struct unmap_desc *desc);
 
 void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte);
 
diff --git a/mm/memory.c b/mm/memory.c
index 8d4d976311037..98c5ffd28a109 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -387,15 +387,14 @@ void free_pgd_range(struct mmu_gather *tlb,
  * The tree_max differs from the ceiling when a dup_mmap() failed and the tree
  * has unrelated data to the mm_struct being torn down.
  */
-void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
-		   struct vm_area_struct *vma, unsigned long floor,
-		   unsigned long ceiling, unsigned long tree_max,
-		   bool mm_wr_locked)
+void free_pgtables(struct mmu_gather *tlb, struct unmap_desc *desc)
 {
 	struct unlink_vma_file_batch vb;
+	struct ma_state *mas = desc->mas;
+	struct vm_area_struct *vma = desc->first;
 
 	/* underflow can happen and is fine */
-	WARN_ON_ONCE(tree_max - 1 > ceiling - 1);
+	WARN_ON_ONCE(desc->tree_max - 1 > desc->last_pgaddr - 1);
 
 	tlb_free_vmas(tlb);
 
@@ -407,13 +406,13 @@ void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
 		 * Note: USER_PGTABLES_CEILING may be passed as ceiling and may
 		 * be 0.  This will underflow and is okay.
 		 */
-		next = mas_find(mas, tree_max - 1);
+		next = mas_find(mas, desc->tree_max - 1);
 
 		/*
 		 * Hide vma from rmap and truncate_pagecache before freeing
 		 * pgtables
 		 */
-		if (mm_wr_locked)
+		if (desc->mm_wr_locked)
 			vma_start_write(vma);
 		unlink_anon_vmas(vma);
 
@@ -425,16 +424,16 @@ void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
 		 */
 		while (next && next->vm_start <= vma->vm_end + PMD_SIZE) {
 			vma = next;
-			next = mas_find(mas, tree_max - 1);
-			if (mm_wr_locked)
+			next = mas_find(mas, desc->tree_max - 1);
+			if (desc->mm_wr_locked)
 				vma_start_write(vma);
 			unlink_anon_vmas(vma);
 			unlink_file_vma_batch_add(&vb, vma);
 		}
 		unlink_file_vma_batch_final(&vb);
 
-		free_pgd_range(tlb, addr, vma->vm_end,
-			floor, next ? next->vm_start : ceiling);
+		free_pgd_range(tlb, addr, vma->vm_end, desc->first_pgaddr,
+			       next ? next->vm_start : desc->last_pgaddr);
 		vma = next;
 	} while (vma);
 }
diff --git a/mm/mmap.c b/mm/mmap.c
index 6011f62b0a294..9908481452780 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1311,10 +1311,10 @@ void exit_mmap(struct mm_struct *mm)
 	 */
 	mm_flags_set(MMF_OOM_SKIP, mm);
 	mmap_write_lock(mm);
+	unmap.mm_wr_locked = true;
 	mt_clear_in_rcu(&mm->mm_mt);
-	vma_iter_set(&vmi, vma->vm_end);
-	free_pgtables(&tlb, &vmi.mas, vma, FIRST_USER_ADDRESS,
-		      USER_PGTABLES_CEILING, USER_PGTABLES_CEILING, true);
+	vma_iter_set(&vmi, unmap.tree_reset);
+	free_pgtables(&tlb, &unmap);
 	tlb_finish_mmu(&tlb);
 
 	/*
diff --git a/mm/vma.c b/mm/vma.c
index ad64cd9795ef3..ba155a539d160 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -476,16 +476,13 @@ void remove_vma(struct vm_area_struct *vma)
 void unmap_region(struct unmap_desc *desc)
 {
 	struct mm_struct *mm = desc->first->vm_mm;
-	struct ma_state *mas = desc->mas;
 	struct mmu_gather tlb;
 
 	tlb_gather_mmu(&tlb, mm);
 	update_hiwater_rss(mm);
 	unmap_vmas(&tlb, desc);
-	mas_set(mas, desc->tree_reset);
-	free_pgtables(&tlb, mas, desc->first, desc->first_pgaddr,
-		      desc->last_pgaddr, desc->tree_max,
-		      desc->mm_wr_locked);
+	mas_set(desc->mas, desc->tree_reset);
+	free_pgtables(&tlb, desc);
 	tlb_finish_mmu(&tlb);
 }
 
diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h
index d73ad4747d40a..435c5a24480bc 100644
--- a/tools/testing/vma/vma_internal.h
+++ b/tools/testing/vma/vma_internal.h
@@ -892,17 +892,10 @@ static inline void unmap_vmas(struct mmu_gather *tlb, struct unmap_desc *unmap)
 	(void)unmap;
 }
 
-static inline void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
-		   struct vm_area_struct *vma, unsigned long floor,
-		   unsigned long ceiling, unsigned long tree_max,
-		   bool mm_wr_locked)
+static inline void free_pgtables(struct mmu_gather *tlb, struct unmap_desc *desc)
 {
 	(void)tlb;
-	(void)mas;
-	(void)vma;
-	(void)floor;
-	(void)ceiling;
-	(void)mm_wr_locked;
+	(void)desc;
 }
 
 static inline void mapping_unmap_writable(struct address_space *)
-- 
2.47.2