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Diffstat (limited to 'mm/hugetlb.c')
-rw-r--r--mm/hugetlb.c35
1 files changed, 22 insertions, 13 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ea2ed8e301ef..eaaec19caa7c 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5340,7 +5340,7 @@ again:
break;
}
ret = copy_user_large_folio(new_folio, pte_folio,
- ALIGN_DOWN(addr, sz), dst_vma);
+ addr, dst_vma);
folio_put(pte_folio);
if (ret) {
folio_put(new_folio);
@@ -5402,6 +5402,7 @@ static void move_huge_pte(struct vm_area_struct *vma, unsigned long old_addr,
unsigned long new_addr, pte_t *src_pte, pte_t *dst_pte,
unsigned long sz)
{
+ bool need_clear_uffd_wp = vma_has_uffd_without_event_remap(vma);
struct hstate *h = hstate_vma(vma);
struct mm_struct *mm = vma->vm_mm;
spinlock_t *src_ptl, *dst_ptl;
@@ -5418,7 +5419,18 @@ static void move_huge_pte(struct vm_area_struct *vma, unsigned long old_addr,
spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
pte = huge_ptep_get_and_clear(mm, old_addr, src_pte);
- set_huge_pte_at(mm, new_addr, dst_pte, pte, sz);
+
+ if (need_clear_uffd_wp && pte_marker_uffd_wp(pte))
+ huge_pte_clear(mm, new_addr, dst_pte, sz);
+ else {
+ if (need_clear_uffd_wp) {
+ if (pte_present(pte))
+ pte = huge_pte_clear_uffd_wp(pte);
+ else if (is_swap_pte(pte))
+ pte = pte_swp_clear_uffd_wp(pte);
+ }
+ set_huge_pte_at(mm, new_addr, dst_pte, pte, sz);
+ }
if (src_ptl != dst_ptl)
spin_unlock(src_ptl);
@@ -6643,8 +6655,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
*foliop = NULL;
goto out;
}
- ret = copy_user_large_folio(folio, *foliop,
- ALIGN_DOWN(dst_addr, size), dst_vma);
+ ret = copy_user_large_folio(folio, *foliop, dst_addr, dst_vma);
folio_put(*foliop);
*foliop = NULL;
if (ret) {
@@ -7212,7 +7223,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
spte = hugetlb_walk(svma, saddr,
vma_mmu_pagesize(svma));
if (spte) {
- get_page(virt_to_page(spte));
+ ptdesc_pmd_pts_inc(virt_to_ptdesc(spte));
break;
}
}
@@ -7227,7 +7238,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
(pmd_t *)((unsigned long)spte & PAGE_MASK));
mm_inc_nr_pmds(mm);
} else {
- put_page(virt_to_page(spte));
+ ptdesc_pmd_pts_dec(virt_to_ptdesc(spte));
}
spin_unlock(&mm->page_table_lock);
out:
@@ -7239,10 +7250,6 @@ out:
/*
* unmap huge page backed by shared pte.
*
- * Hugetlb pte page is ref counted at the time of mapping. If pte is shared
- * indicated by page_count > 1, unmap is achieved by clearing pud and
- * decrementing the ref count. If count == 1, the pte page is not shared.
- *
* Called with page table lock held.
*
* returns: 1 successfully unmapped a shared pte page
@@ -7251,18 +7258,20 @@ out:
int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep)
{
+ unsigned long sz = huge_page_size(hstate_vma(vma));
pgd_t *pgd = pgd_offset(mm, addr);
p4d_t *p4d = p4d_offset(pgd, addr);
pud_t *pud = pud_offset(p4d, addr);
i_mmap_assert_write_locked(vma->vm_file->f_mapping);
hugetlb_vma_assert_locked(vma);
- BUG_ON(page_count(virt_to_page(ptep)) == 0);
- if (page_count(virt_to_page(ptep)) == 1)
+ if (sz != PMD_SIZE)
+ return 0;
+ if (!ptdesc_pmd_pts_count(virt_to_ptdesc(ptep)))
return 0;
pud_clear(pud);
- put_page(virt_to_page(ptep));
+ ptdesc_pmd_pts_dec(virt_to_ptdesc(ptep));
mm_dec_nr_pmds(mm);
return 1;
}