mm: Update file times from fault path only if .page_mkwrite is not set (41c4d25f) · Commits · 戴 / test

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. Tested-by:

Kamal Mostafa <kamal@canonical.com> Tested-by:

Peter M. Petrakis <peter.petrakis@canonical.com> Tested-by:

Dann Frazier <dann.frazier@canonical.com> Tested-by:

Massimo Morana <massimo.morana@canonical.com> Signed-off-by:

Jan Kara <jack@suse.cz> Signed-off-by:

Al Viro <viro@zeniv.linux.org.uk>

mm/memory.c

+7 −7

Original line number	Diff line number	Diff line
		@@ -2638,6 +2638,9 @@ 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) {
		@@ -2655,10 +2658,6 @@ reuse:
		}
		}

		/* file_update_time outside page_lock */
		if (vma->vm_file)
		file_update_time(vma->vm_file);

		return ret;
		}

		@@ -3327,12 +3326,13 @@ static int __do_fault(struct mm_struct mm, struct vm_area_struct vma,

		if (dirty_page) {
		struct address_space *mapping = page->mapping;
		int dirtied = 0;

		if (set_page_dirty(dirty_page))
		page_mkwrite = 1;
		dirtied = 1;
		unlock_page(dirty_page);
		put_page(dirty_page);
		if (page_mkwrite && mapping) {
		if ((dirtied \|\| page_mkwrite) && mapping) {
		/*
		* Some device drivers do not set page.mapping but still
		* dirty their pages
		@@ -3341,7 +3341,7 @@ 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);

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