[PATCH 11/11] mm: Update file times from fault path only if .page_mkwrite is not set

[Jan Kara <jack@suse.cz>]

Filesystems wanting to properly support freezing need to have control
when file_update_time() is called. After pushing file_update_time()
to all relevant .page_mkwrite implementations we can just stop calling
file_update_time() when filesystem implements .page_mkwrite.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 mm/memory.c |    9 ++++-----
 1 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index fa2f04e..17b72d7 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2621,6 +2621,9 @@ reuse:
 		if (!page_mkwrite) {
 			wait_on_page_locked(dirty_page);
 			set_page_dirty_balance(dirty_page, page_mkwrite);
+			/* file_update_time outside page_lock */
+			if (vma->vm_file)
+				file_update_time(vma->vm_file);
 		}
 		put_page(dirty_page);
 		if (page_mkwrite) {
@@ -2638,10 +2641,6 @@ reuse:
 			}
 		}
 
-		/* file_update_time outside page_lock */
-		if (vma->vm_file)
-			file_update_time(vma->vm_file);
-
 		return ret;
 	}
 
@@ -3324,7 +3323,7 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 		}
 
 		/* file_update_time outside page_lock */
-		if (vma->vm_file)
+		if (vma->vm_file && !page_mkwrite)
 			file_update_time(vma->vm_file);
 	} else {
 		unlock_page(vmf.page);
-- 
1.7.1