Update ctime and mtime for memory-mapped files

Update ctime and mtime for memory-mapped files at a write access on
a present, read-only PTE, as well as at a write on a non-present PTE.

Signed-off-by: Anton Salikhmetov <salikhmetov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory.c b/mm/memory.c
index 6dd1cd8..4b0144b 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1670,6 +1670,9 @@ gotten:
 unlock:
        pte_unmap_unlock(page_table, ptl);
        if (dirty_page) {
+               if (vma->vm_file)
+                       file_update_time(vma->vm_file);
+
                /*
                 * Yes, Virginia, this is actually required to prevent a race
                 * with clear_page_dirty_for_io() from clearing the page dirty
@@ -2343,6 +2346,9 @@ out_unlocked:
        if (anon)
                page_cache_release(vmf.page);
        else if (dirty_page) {
+               if (vma->vm_file)
+                       file_update_time(vma->vm_file);
+
                set_page_dirty_balance(dirty_page, page_mkwrite);
                put_page(dirty_page);
        }