1 files changed, 19 insertions, 0 deletions

diff --git a/mm/fremap.c b/mm/fremap.c
index 5f50d736a037..c395b1abf082 100644
--- a/mm/fremap.c
+++ b/mm/fremap.c
@@ -181,6 +181,25 @@ asmlinkage long sys_remap_file_pages(unsigned long start, unsigned long size,
                         goto retry;
                 }
                 mapping = vma->vm_file->f_mapping;
+                /*
+                 * page_mkclean doesn't work on nonlinear vmas, so if
+                 * dirty pages need to be accounted, emulate with linear
+                 * vmas.
+                 */
+                if (mapping_cap_account_dirty(mapping)) {
+                        unsigned long addr;
+
+                        flags &= MAP_NONBLOCK;
+                        addr = mmap_region(vma->vm_file, start, size,
+                                        flags, vma->vm_flags, pgoff, 1);
+                        if (IS_ERR_VALUE(addr)) {
+                                err = addr;
+                        } else {
+                                BUG_ON(addr != start);
+                                err = 0;
+                        }
+                        goto out;
+                }
                 spin_lock(&mapping->i_mmap_lock);
                 flush_dcache_mmap_lock(mapping);
                 vma->vm_flags |= VM_NONLINEAR;