[PATCH -v8 2/4] Update ctime and mtime for memory-mapped files

[Anton Salikhmetov <salikhmetov@gmail.com>]

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>
---
 mm/memory.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index 6dd1cd8..4b0144b 100644
--- 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);
 	}
-- 
1.4.4.4