[13/20] mm: Pass vm_fault structure into do_page_mkwrite()

Commit Message

Jan Kara Sept. 27, 2016, 4:08 p.m. UTC

We will need more information in the ->page_mkwrite() helper for DAX to
be able to fully finish faults there. Pass vm_fault structure to
do_page_mkwrite() and use it there so that information propagates
properly from upper layers.

Signed-off-by: Jan Kara <[e-mail]>
---
 mm/memory.c | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

Comments

Ross Zwisler Oct. 17, 2016, 10:29 p.m. UTC | #1

On Tue, Sep 27, 2016 at 06:08:17PM +0200, Jan Kara wrote:
> We will need more information in the ->page_mkwrite() helper for DAX to
> be able to fully finish faults there. Pass vm_fault structure to
> do_page_mkwrite() and use it there so that information propagates
> properly from upper layers.
> 
> Signed-off-by: Jan Kara <[e-mail]>

Reviewed-by: Ross Zwisler <[e-mail]>

Patch

diff --git a/mm/memory.c b/mm/memory.c
index 0643b3b5a12a..7c87edaa7a8f 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2034,20 +2034,14 @@  static gfp_t __get_fault_gfp_mask(struct vm_area_struct *vma)
  *
  * We do this without the lock held, so that it can sleep if it needs to.
  */
-static int do_page_mkwrite(struct vm_area_struct *vma, struct page *page,
-	       unsigned long address)
+static int do_page_mkwrite(struct vm_fault *vmf)
 {
-	struct vm_fault vmf;
 	int ret;
+	struct page *page = vmf->page;
 
-	vmf.virtual_address = address & PAGE_MASK;
-	vmf.pgoff = page->index;
-	vmf.flags = FAULT_FLAG_WRITE|FAULT_FLAG_MKWRITE;
-	vmf.gfp_mask = __get_fault_gfp_mask(vma);
-	vmf.page = page;
-	vmf.cow_page = NULL;
+	vmf->flags = FAULT_FLAG_WRITE|FAULT_FLAG_MKWRITE;
 
-	ret = vma->vm_ops->page_mkwrite(vma, &vmf);
+	ret = vmf->vma->vm_ops->page_mkwrite(vmf->vma, vmf);
 	if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
 		return ret;
 	if (unlikely(!(ret & VM_FAULT_LOCKED))) {
@@ -2323,7 +2317,8 @@  static int wp_page_shared(struct vm_fault *vmf, struct page *old_page)
 		int tmp;
 
 		pte_unmap_unlock(vmf->pte, vmf->ptl);
-		tmp = do_page_mkwrite(vma, old_page, vmf->address);
+		vmf->page = old_page;
+		tmp = do_page_mkwrite(vmf);
 		if (unlikely(!tmp || (tmp &
 				      (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))) {
 			put_page(old_page);
@@ -3286,7 +3281,7 @@  static int do_shared_fault(struct vm_fault *vmf)
 	 */
 	if (vma->vm_ops->page_mkwrite) {
 		unlock_page(vmf->page);
-		tmp = do_page_mkwrite(vma, vmf->page, vmf->address);
+		tmp = do_page_mkwrite(vmf);
 		if (unlikely(!tmp ||
 				(tmp & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))) {
 			put_page(vmf->page);