mm/mremap: use vmi version of vma_merge()

Use the vma iterator so that the iterator can be invalidated or updated to
avoid each caller doing so.

Link: https://lkml.kernel.org/r/20230120162650.984577-27-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/mremap.c b/mm/mremap.c
index 3cc64c3f8bdb364264ea9bb408511e09f30d03ac..f161516ab3c1e68414b3bbface08e7748e218f16 100644 (file)
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -1018,6 +1018,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
                        unsigned long extension_end = addr + new_len;
                        pgoff_t extension_pgoff = vma->vm_pgoff +
                                ((extension_start - vma->vm_start) >> PAGE_SHIFT);
+                       VMA_ITERATOR(vmi, mm, extension_start);
 
                        if (vma->vm_flags & VM_ACCOUNT) {
                                if (security_vm_enough_memory_mm(mm, pages)) {
@@ -1042,10 +1043,12 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
                         * when a vma would be actually removed due to a merge.
                         */
                        if (!vma->vm_ops || !vma->vm_ops->close) {
-                               vma = vma_merge(mm, vma, extension_start, extension_end,
-                                       vma->vm_flags, vma->anon_vma, vma->vm_file,
-                                       extension_pgoff, vma_policy(vma),
-                                       vma->vm_userfaultfd_ctx, anon_vma_name(vma));
+                               vma = vmi_vma_merge(&vmi, mm, vma,
+                                      extension_start, extension_end,
+                                      vma->vm_flags, vma->anon_vma,
+                                      vma->vm_file, extension_pgoff,
+                                      vma_policy(vma), vma->vm_userfaultfd_ctx,
+                                      anon_vma_name(vma));
                        } else if (vma_adjust(vma, vma->vm_start, addr + new_len,
                                   vma->vm_pgoff, NULL)) {
                                vma = NULL;