mm: remove the vma linked list

Replace any vm_next use with vma_find().

Update free_pgtables(), unmap_vmas(), and zap_page_range() to use the
maple tree.

Use the new free_pgtables() and unmap_vmas() in do_mas_align_munmap().  At
the same time, alter the loop to be more compact.

Now that free_pgtables() and unmap_vmas() take a maple tree as an
argument, rearrange do_mas_align_munmap() to use the new tree to hold the
vmas to remove.

Remove __vma_link_list() and __vma_unlink_list() as they are exclusively
used to update the linked list.

Drop linked list update from __insert_vm_struct().

Rework validation of tree as it was depending on the linked list.

[yang.lee@linux.alibaba.com: fix one kernel-doc comment]
  Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=1949
  Link: https://lkml.kernel.org/r/20220824021918.94116-1-yang.lee@linux.alibaba.comLink: https://lkml.kernel.org/r/20220906194824.2110408-69-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 0 insertions, 6 deletions

diff --git a/mm/nommu.c b/mm/nommu.c
index 269df51e9226..214c70e1d059 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -584,17 +584,12 @@ static void setup_vma_to_mm(struct vm_area_struct *vma, struct mm_struct *mm)
 static void mas_add_vma_to_mm(struct ma_state *mas, struct mm_struct *mm,
 			      struct vm_area_struct *vma)
 {
-	struct vm_area_struct *prev;
-
 	BUG_ON(!vma->vm_region);
 
 	setup_vma_to_mm(vma, mm);
 
-	prev = mas_prev(mas, 0);
-	mas_reset(mas);
 	/* add the VMA to the tree */
 	vma_mas_store(vma, mas);
-	__vma_link_list(mm, vma, prev);
 }
 
 /*
@@ -647,7 +642,6 @@ static int delete_vma_from_mm(struct vm_area_struct *vma)
 
 	/* remove from the MM's tree and list */
 	vma_mas_remove(vma, &mas);
-	__vma_unlink_list(vma->vm_mm, vma);
 	return 0;
 }