[PATCH v1 6/8] mm: hugetlb: Convert set_huge_pte_at() to take vma

Ryan Roberts
2023-09-21T21:50:29Z

In order to fix a bug, arm64 needs access to the vma inside it's
implementation of set_huge_pte_at(). Provide for this by converting the
mm parameter to be a vma. Any implementations that require the mm can
access it via vma->vm_mm.

This commit makes the required modifications to the core mm. Separate
commits update the arches, before the actual bug is fixed in arm64.

No behavioral changes intended.

Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
---
include/asm-generic/hugetlb.h | 6 +++---
include/linux/hugetlb.h | 6 +++---
mm/damon/vaddr.c | 2 +-
mm/hugetlb.c | 30 +++++++++++++++---------------
mm/migrate.c | 2 +-
mm/rmap.c | 10 +++++-----
mm/vmalloc.c | 5 ++++-
7 files changed, 32 insertions(+), 29 deletions(-)

diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
index 4da02798a00b..515e4777fb65 100644
--- a/include/asm-generic/hugetlb.h
+++ b/include/asm-generic/hugetlb.h
@@ -75,10 +75,10 @@ static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb,
#endif

#ifndef __HAVE_ARCH_HUGE_SET_HUGE_PTE_AT
-static inline void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pte)
+static inline void set_huge_pte_at(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep, pte_t pte)
{
- set_pte_at(mm, addr, ptep, pte);
+ set_pte_at(vma->vm_mm, addr, ptep, pte);
}
#endif

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 5b2626063f4f..08184f32430c 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -984,7 +984,7 @@ static inline void huge_ptep_modify_prot_commit(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep,
pte_t old_pte, pte_t pte)
{
- set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
+ set_huge_pte_at(vma, addr, ptep, pte);
}
#endif

@@ -1172,8 +1172,8 @@ static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
#endif
}

-static inline void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pte)
+static inline void set_huge_pte_at(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep, pte_t pte)
{
}

diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index 4c81a9dbd044..55da8cee8fbc 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -347,7 +347,7 @@ static void damon_hugetlb_mkold(pte_t *pte, struct mm_struct *mm,
if (pte_young(entry)) {
referenced = true;
entry = pte_mkold(entry);
- set_huge_pte_at(mm, addr, pte, entry);
+ set_huge_pte_at(vma, addr, pte, entry);
}

#ifdef CONFIG_MMU_NOTIFIER
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ba6d39b71cb1..bcc30cd62586 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4988,7 +4988,7 @@ hugetlb_install_folio(struct vm_area_struct *vma, pte_t *ptep, unsigned long add
hugepage_add_new_anon_rmap(new_folio, vma, addr);
if (userfaultfd_wp(vma) && huge_pte_uffd_wp(old))
newpte = huge_pte_mkuffd_wp(newpte);
- set_huge_pte_at(vma->vm_mm, addr, ptep, newpte);
+ set_huge_pte_at(vma, addr, ptep, newpte);
hugetlb_count_add(pages_per_huge_page(hstate_vma(vma)), vma->vm_mm);
folio_set_hugetlb_migratable(new_folio);
}
@@ -5065,7 +5065,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
} else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) {
if (!userfaultfd_wp(dst_vma))
entry = huge_pte_clear_uffd_wp(entry);
- set_huge_pte_at(dst, addr, dst_pte, entry);
+ set_huge_pte_at(dst_vma, addr, dst_pte, entry);
} else if (unlikely(is_hugetlb_entry_migration(entry))) {
swp_entry_t swp_entry = pte_to_swp_entry(entry);
bool uffd_wp = pte_swp_uffd_wp(entry);
@@ -5080,17 +5080,17 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
entry = swp_entry_to_pte(swp_entry);
if (userfaultfd_wp(src_vma) && uffd_wp)
entry = pte_swp_mkuffd_wp(entry);
- set_huge_pte_at(src, addr, src_pte, entry);
+ set_huge_pte_at(src_vma, addr, src_pte, entry);
}
if (!userfaultfd_wp(dst_vma))
entry = huge_pte_clear_uffd_wp(entry);
- set_huge_pte_at(dst, addr, dst_pte, entry);
+ set_huge_pte_at(dst_vma, addr, dst_pte, entry);
} else if (unlikely(is_pte_marker(entry))) {
pte_marker marker = copy_pte_marker(
pte_to_swp_entry(entry), dst_vma);

if (marker)
- set_huge_pte_at(dst, addr, dst_pte,
+ set_huge_pte_at(dst_vma, addr, dst_pte,
make_pte_marker(marker));
} else {
entry = huge_ptep_get(src_pte);
@@ -5166,7 +5166,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
if (!userfaultfd_wp(dst_vma))
entry = huge_pte_clear_uffd_wp(entry);

- set_huge_pte_at(dst, addr, dst_pte, entry);
+ set_huge_pte_at(dst_vma, addr, dst_pte, entry);
hugetlb_count_add(npages, dst);
}
spin_unlock(src_ptl);
@@ -5202,7 +5202,7 @@ 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);
+ set_huge_pte_at(vma, new_addr, dst_pte, pte);

if (src_ptl != dst_ptl)
spin_unlock(src_ptl);
@@ -5336,7 +5336,7 @@ static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct
*/
if (pte_swp_uffd_wp_any(pte) &&
!(zap_flags & ZAP_FLAG_DROP_MARKER))
- set_huge_pte_at(mm, address, ptep,
+ set_huge_pte_at(vma, address, ptep,
make_pte_marker(PTE_MARKER_UFFD_WP));
else
huge_pte_clear(mm, address, ptep, sz);
@@ -5370,7 +5370,7 @@ static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct
/* Leave a uffd-wp pte marker if needed */
if (huge_pte_uffd_wp(pte) &&
!(zap_flags & ZAP_FLAG_DROP_MARKER))
- set_huge_pte_at(mm, address, ptep,
+ set_huge_pte_at(vma, address, ptep,
make_pte_marker(PTE_MARKER_UFFD_WP));
hugetlb_count_sub(pages_per_huge_page(h), mm);
page_remove_rmap(page, vma, true);
@@ -5676,7 +5676,7 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma,
hugepage_add_new_anon_rmap(new_folio, vma, haddr);
if (huge_pte_uffd_wp(pte))
newpte = huge_pte_mkuffd_wp(newpte);
- set_huge_pte_at(mm, haddr, ptep, newpte);
+ set_huge_pte_at(vma, haddr, ptep, newpte);
folio_set_hugetlb_migratable(new_folio);
/* Make the old page be freed below */
new_folio = old_folio;
@@ -5972,7 +5972,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
*/
if (unlikely(pte_marker_uffd_wp(old_pte)))
new_pte = huge_pte_mkuffd_wp(new_pte);
- set_huge_pte_at(mm, haddr, ptep, new_pte);
+ set_huge_pte_at(vma, haddr, ptep, new_pte);

hugetlb_count_add(pages_per_huge_page(h), mm);
if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
@@ -6261,7 +6261,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
}

_dst_pte = make_pte_marker(PTE_MARKER_POISONED);
- set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte);
+ set_huge_pte_at(dst_vma, dst_addr, dst_pte, _dst_pte);

/* No need to invalidate - it was non-present before */
update_mmu_cache(dst_vma, dst_addr, dst_pte);
@@ -6412,7 +6412,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
if (wp_enabled)
_dst_pte = huge_pte_mkuffd_wp(_dst_pte);

- set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte);
+ set_huge_pte_at(dst_vma, dst_addr, dst_pte, _dst_pte);

hugetlb_count_add(pages_per_huge_page(h), dst_mm);

@@ -6598,7 +6598,7 @@ long hugetlb_change_protection(struct vm_area_struct *vma,
else if (uffd_wp_resolve)
newpte = pte_swp_clear_uffd_wp(newpte);
if (!pte_same(pte, newpte))
- set_huge_pte_at(mm, address, ptep, newpte);
+ set_huge_pte_at(vma, address, ptep, newpte);
} else if (unlikely(is_pte_marker(pte))) {
/* No other markers apply for now. */
WARN_ON_ONCE(!pte_marker_uffd_wp(pte));
@@ -6622,7 +6622,7 @@ long hugetlb_change_protection(struct vm_area_struct *vma,
/* None pte */
if (unlikely(uffd_wp))
/* Safe to modify directly (none->non-present). */
- set_huge_pte_at(mm, address, ptep,
+ set_huge_pte_at(vma, address, ptep,
make_pte_marker(PTE_MARKER_UFFD_WP));
}
spin_unlock(ptl);
diff --git a/mm/migrate.c b/mm/migrate.c
index b7fa020003f3..6aa752984f32 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -251,7 +251,7 @@ static bool remove_migration_pte(struct folio *folio,
rmap_flags);
else
page_dup_file_rmap(new, true);
- set_huge_pte_at(vma->vm_mm, pvmw.address, pvmw.pte, pte);
+ set_huge_pte_at(vma, pvmw.address, pvmw.pte, pte);
} else
#endif
{
diff --git a/mm/rmap.c b/mm/rmap.c
index ec7f8e6c9e48..a6353a0c67e8 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1628,7 +1628,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,
pteval = swp_entry_to_pte(make_hwpoison_entry(subpage));
if (folio_test_hugetlb(folio)) {
hugetlb_count_sub(folio_nr_pages(folio), mm);
- set_huge_pte_at(mm, address, pvmw.pte, pteval);
+ set_huge_pte_at(vma, address, pvmw.pte, pteval);
} else {
dec_mm_counter(mm, mm_counter(&folio->page));
set_pte_at(mm, address, pvmw.pte, pteval);
@@ -2020,7 +2020,7 @@ static bool try_to_migrate_one(struct folio *folio, struct vm_area_struct *vma,
pteval = swp_entry_to_pte(make_hwpoison_entry(subpage));
if (folio_test_hugetlb(folio)) {
hugetlb_count_sub(folio_nr_pages(folio), mm);
- set_huge_pte_at(mm, address, pvmw.pte, pteval);
+ set_huge_pte_at(vma, address, pvmw.pte, pteval);
} else {
dec_mm_counter(mm, mm_counter(&folio->page));
set_pte_at(mm, address, pvmw.pte, pteval);
@@ -2044,7 +2044,7 @@ static bool try_to_migrate_one(struct folio *folio, struct vm_area_struct *vma,

if (arch_unmap_one(mm, vma, address, pteval) < 0) {
if (folio_test_hugetlb(folio))
- set_huge_pte_at(mm, address, pvmw.pte, pteval);
+ set_huge_pte_at(vma, address, pvmw.pte, pteval);
else
set_pte_at(mm, address, pvmw.pte, pteval);
ret = false;
@@ -2058,7 +2058,7 @@ static bool try_to_migrate_one(struct folio *folio, struct vm_area_struct *vma,
if (anon_exclusive &&
page_try_share_anon_rmap(subpage)) {
if (folio_test_hugetlb(folio))
- set_huge_pte_at(mm, address, pvmw.pte, pteval);
+ set_huge_pte_at(vma, address, pvmw.pte, pteval);
else
set_pte_at(mm, address, pvmw.pte, pteval);
ret = false;
@@ -2090,7 +2090,7 @@ static bool try_to_migrate_one(struct folio *folio, struct vm_area_struct *vma,
if (pte_uffd_wp(pteval))
swp_pte = pte_swp_mkuffd_wp(swp_pte);
if (folio_test_hugetlb(folio))
- set_huge_pte_at(mm, address, pvmw.pte, swp_pte);
+ set_huge_pte_at(vma, address, pvmw.pte, swp_pte);
else
set_pte_at(mm, address, pvmw.pte, swp_pte);
trace_set_migration_pte(address, pte_val(swp_pte),
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ef8599d394fd..10fa40222f30 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -94,6 +94,9 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
phys_addr_t phys_addr, pgprot_t prot,
unsigned int max_page_shift, pgtbl_mod_mask *mask)
{
+#ifdef CONFIG_HUGETLB_PAGE
+ struct vm_area_struct vma = TLB_FLUSH_VMA(&init_mm, 0);
+#endif
pte_t *pte;
u64 pfn;
unsigned long size = PAGE_SIZE;
@@ -111,7 +114,7 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
pte_t entry = pfn_pte(pfn, prot);

entry = arch_make_huge_pte(entry, ilog2(size), 0);
- set_huge_pte_at(&init_mm, addr, pte, entry);
+ set_huge_pte_at(&vma, addr, pte, entry);
pfn += PFN_DOWN(size);
continue;
}
--
2.25.1