diff options
| author | Christoph Hellwig <hch@lst.de> | 2020-10-17 16:15:14 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-18 09:27:10 -0700 |
| commit | eeb4a05fcef39a720d24846356cf65a07e71d7a1 (patch) | |
| tree | b86c5e8cb38f95eb7f4cbd89dadb50c6caecee86 | |
| parent | 3e9a9e256b1e1e6e8f19faf76fa9c37578ae35ee (diff) | |
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@kernel.org>.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Link: https://lkml.kernel.org/r/20201002122204.1534411-5-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/memory.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/mm/memory.c b/mm/memory.c index 589afe45d0b3..c48f8df6e502 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2391,13 +2391,15 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, 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(); |