diff options
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index fac917b78102..29102e3ddf84 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1511,8 +1511,7 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) unsigned long haddr = vmf->address & HPAGE_PMD_MASK; int page_nid = NUMA_NO_NODE; int target_nid, last_cpupid = (-1 & LAST_CPUPID_MASK); - bool migrated = false; - bool was_writable = pmd_savedwrite(oldpmd); + bool migrated = false, writable = false; int flags = 0; vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd); @@ -1522,12 +1521,22 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) } pmd = pmd_modify(oldpmd, vma->vm_page_prot); + + /* + * Detect now whether the PMD could be writable; this information + * is only valid while holding the PT lock. + */ + writable = pmd_write(pmd); + if (!writable && vma_wants_manual_pte_write_upgrade(vma) && + can_change_pmd_writable(vma, vmf->address, pmd)) + writable = true; + page = vm_normal_page_pmd(vma, haddr, pmd); if (!page) goto out_map; /* See similar comment in do_numa_page for explanation */ - if (!was_writable) + if (!writable) flags |= TNF_NO_GROUP; page_nid = page_to_nid(page); @@ -1546,6 +1555,7 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) } spin_unlock(vmf->ptl); + writable = false; migrated = migrate_misplaced_page(page, vma, target_nid); if (migrated) { @@ -1572,7 +1582,7 @@ out_map: /* Restore the PMD */ pmd = pmd_modify(oldpmd, vma->vm_page_prot); pmd = pmd_mkyoung(pmd); - if (was_writable) + if (writable) pmd = pmd_mkwrite(pmd); set_pmd_at(vma->vm_mm, haddr, vmf->pmd, pmd); update_mmu_cache_pmd(vma, vmf->address, vmf->pmd); @@ -1813,11 +1823,10 @@ int change_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, struct mm_struct *mm = vma->vm_mm; spinlock_t *ptl; pmd_t oldpmd, entry; - bool preserve_write; - int ret; bool prot_numa = cp_flags & MM_CP_PROT_NUMA; bool uffd_wp = cp_flags & MM_CP_UFFD_WP; bool uffd_wp_resolve = cp_flags & MM_CP_UFFD_WP_RESOLVE; + int ret = 1; tlb_change_page_size(tlb, HPAGE_PMD_SIZE); @@ -1828,9 +1837,6 @@ int change_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, if (!ptl) return 0; - preserve_write = prot_numa && pmd_write(*pmd); - ret = 1; - #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION if (is_swap_pmd(*pmd)) { swp_entry_t entry = pmd_to_swp_entry(*pmd); @@ -1910,8 +1916,6 @@ int change_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, oldpmd = pmdp_invalidate_ad(vma, addr, pmd); entry = pmd_modify(oldpmd, newprot); - if (preserve_write) - entry = pmd_mk_savedwrite(entry); if (uffd_wp) { entry = pmd_wrprotect(entry); entry = pmd_mkuffd_wp(entry); |