mm: softdirty: respect VM_SOFTDIRTY in PTE holes

[firefly-linux-kernel-4.4.55.git] / fs / proc / task_mmu.c

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index cfa63ee92c96c9e8b715fc73864ca81053c2b237..dfc791c42d6491c6d1a4537e6ee5d7c9bd21a24b 100644 (file)
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -925,15 +925,30 @@ static int pagemap_pte_hole(unsigned long start, unsigned long end,
                                struct mm_walk *walk)
 {
        struct pagemapread *pm = walk->private;
-       unsigned long addr;
+       unsigned long addr = start;
        int err = 0;
-       pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2));
 
-       for (addr = start; addr < end; addr += PAGE_SIZE) {
-               err = add_to_pagemap(addr, &pme, pm);
-               if (err)
-                       break;
+       while (addr < end) {
+               struct vm_area_struct *vma = find_vma(walk->mm, addr);
+               pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2));
+               unsigned long vm_end;
+
+               if (!vma) {
+                       vm_end = end;
+               } else {
+                       vm_end = min(end, vma->vm_end);
+                       if (vma->vm_flags & VM_SOFTDIRTY)
+                               pme.pme |= PM_STATUS2(pm->v2, __PM_SOFT_DIRTY);
+               }
+
+               for (; addr < vm_end; addr += PAGE_SIZE) {
+                       err = add_to_pagemap(addr, &pme, pm);
+                       if (err)
+                               goto out;
+               }
        }
+
+out:
        return err;
 }