diff options
Diffstat (limited to 'mm/userfaultfd.c')
| -rw-r--r-- | mm/userfaultfd.c | 18 |
1 files changed, 7 insertions, 11 deletions
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index e6dfd5f28acd..927086bb4a3c 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -1103,7 +1103,7 @@ static long move_present_ptes(struct mm_struct *mm, /* It's safe to drop the reference now as the page-table is holding one. */ folio_put(*first_src_folio); *first_src_folio = NULL; - arch_enter_lazy_mmu_mode(); + lazy_mmu_mode_enable(); while (true) { orig_src_pte = ptep_get_and_clear(mm, src_addr, src_pte); @@ -1140,7 +1140,7 @@ static long move_present_ptes(struct mm_struct *mm, break; } - arch_leave_lazy_mmu_mode(); + lazy_mmu_mode_disable(); if (src_addr > src_start) flush_tlb_range(src_vma, src_start, src_addr); @@ -1190,17 +1190,13 @@ static int move_swap_pte(struct mm_struct *mm, struct vm_area_struct *dst_vma, * Check if the swap entry is cached after acquiring the src_pte * lock. Otherwise, we might miss a newly loaded swap cache folio. * - * Check swap_map directly to minimize overhead, READ_ONCE is sufficient. * We are trying to catch newly added swap cache, the only possible case is * when a folio is swapped in and out again staying in swap cache, using the * same entry before the PTE check above. The PTL is acquired and released - * twice, each time after updating the swap_map's flag. So holding - * the PTL here ensures we see the updated value. False positive is possible, - * e.g. SWP_SYNCHRONOUS_IO swapin may set the flag without touching the - * cache, or during the tiny synchronization window between swap cache and - * swap_map, but it will be gone very quickly, worst result is retry jitters. + * twice, each time after updating the swap table. So holding + * the PTL here ensures we see the updated value. */ - if (READ_ONCE(si->swap_map[swp_offset(entry)]) & SWAP_HAS_CACHE) { + if (swap_cache_has_folio(entry)) { double_pt_unlock(dst_ptl, src_ptl); return -EAGAIN; } @@ -1274,7 +1270,7 @@ retry: * Use the maywrite version to indicate that dst_pte will be modified, * since dst_pte needs to be none, the subsequent pte_same() check * cannot prevent the dst_pte page from being freed concurrently, so we - * also need to abtain dst_pmdval and recheck pmd_same() later. + * also need to obtain dst_pmdval and recheck pmd_same() later. */ dst_pte = pte_offset_map_rw_nolock(mm, dst_pmd, dst_addr, &dst_pmdval, &dst_ptl); @@ -1330,7 +1326,7 @@ retry: goto out; } - /* If PTE changed after we locked the folio them start over */ + /* If PTE changed after we locked the folio then start over */ if (src_folio && unlikely(!pte_same(src_folio_pte, orig_src_pte))) { ret = -EAGAIN; goto out; |