The patch titled
Subject: mm: allow a NULL fn callback in apply_to_page_range
has been removed from the -mm tree. Its filename was
mm-allow-a-null-fn-callback-in-apply_to_page_range.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Christoph Hellwig <hch@xxxxxx>
Subject: mm: allow a NULL fn callback in apply_to_page_range
Besides calling the callback on each page, apply_to_page_range also has
the effect of pre-faulting all PTEs for the range. To support callers
that only need the pre-faulting, make the callback optional.
Based on a patch from Minchan Kim <minchan@xxxxxxxxxx>.
Link: https://lkml.kernel.org/r/20201002122204.1534411-5-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Cc: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Matthew Auld <matthew.auld@xxxxxxxxx>
Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Cc: Nitin Gupta <ngupta@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
Cc: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)
--- a/mm/memory.c~mm-allow-a-null-fn-callback-in-apply_to_page_range
+++ a/mm/memory.c
@@ -2391,13 +2391,15 @@ static int apply_to_pte_range(struct mm_
arch_enter_lazy_mmu_mode();
- do {
- if (create || !pte_none(*pte)) {
- err = fn(pte++, addr, data);
- if (err)
- break;
- }
- } while (addr += PAGE_SIZE, addr != end);
+ if (fn) {
+ do {
+ if (create || !pte_none(*pte)) {
+ err = fn(pte++, addr, data);
+ if (err)
+ break;
+ }
+ } while (addr += PAGE_SIZE, addr != end);
+ }
*mask |= PGTBL_PTE_MODIFIED;
arch_leave_lazy_mmu_mode();
_
Patches currently in -mm which might be from hch@xxxxxx are
