[PATCH 05/13] mm: convert THP VMA flag tests to use vma_flags_t

["Lorenzo Stoakes (ARM)" <ljs@kernel.org>]

Replace use of the legacy vm_flags_t flags with vma_flags_t values where
VMA flags are tested directly in the THP and khugepaged logic.

The thp_vma_allowable_orders() family of functions, hugepage_madvise() and
khugepaged_enter_vma() continue to take legacy flags for the time being.

Also update BUG_ON()'s to VM_WARN_ON_ONCE() while here.

No functional change intended.

Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
---
 mm/huge_memory.c | 32 ++++++++++++++++----------------
 mm/khugepaged.c  |  8 +++++---
 2 files changed, 21 insertions(+), 19 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 7e589a2fb02d..764e693b422f 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1257,7 +1257,7 @@ __setup("thp_anon=", setup_thp_anon);
 
 pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma)
 {
-	if (likely(vma->vm_flags & VM_WRITE))
+	if (likely(vma_test(vma, VMA_WRITE_BIT)))
 		pmd = pmd_mkwrite(pmd, vma);
 	return pmd;
 }
@@ -1517,7 +1517,7 @@ vm_fault_t do_huge_pmd_device_private(struct vm_fault *vmf)
  */
 gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma)
 {
-	const bool vma_madvised = vma && (vma->vm_flags & VM_HUGEPAGE);
+	const bool vma_madvised = vma && vma_test(vma, VMA_HUGEPAGE_BIT);
 
 	/* Always do synchronous compaction */
 	if (test_bit(TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, &transparent_hugepage_flags))
@@ -1716,10 +1716,9 @@ vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, unsigned long pfn,
 	 * but we need to be consistent with PTEs and architectures that
 	 * can't support a 'special' bit.
 	 */
-	BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
-	BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
-						(VM_PFNMAP|VM_MIXEDMAP));
-	BUG_ON((vma->vm_flags & VM_PFNMAP) && vma_is_cow_mapping(vma));
+	VM_WARN_ON_ONCE(!vma_test_any(vma, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT));
+	VM_WARN_ON_ONCE(vma_test_all(vma, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT));
+	VM_WARN_ON_ONCE(vma_test(vma, VMA_PFNMAP_BIT) && vma_is_cow_mapping(vma));
 
 	if (unlikely(is_huge_zero_pfn(pfn)))
 		return VM_FAULT_SIGBUS;
@@ -1750,7 +1749,7 @@ EXPORT_SYMBOL_GPL(vmf_insert_folio_pmd);
 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
 static pud_t maybe_pud_mkwrite(pud_t pud, struct vm_area_struct *vma)
 {
-	if (likely(vma->vm_flags & VM_WRITE))
+	if (likely(vma_test(vma, VMA_WRITE_BIT)))
 		pud = pud_mkwrite(pud);
 	return pud;
 }
@@ -1827,10 +1826,9 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, unsigned long pfn,
 	 * but we need to be consistent with PTEs and architectures that
 	 * can't support a 'special' bit.
 	 */
-	BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
-	BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
-						(VM_PFNMAP|VM_MIXEDMAP));
-	BUG_ON((vma->vm_flags & VM_PFNMAP) && vma_is_cow_mapping(vma));
+	VM_WARN_ON_ONCE(!vma_test_any(vma, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT));
+	VM_WARN_ON_ONCE(vma_test_all(vma, VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT));
+	VM_WARN_ON_ONCE(vma_test(vma, VMA_PFNMAP_BIT) && vma_is_cow_mapping(vma));
 
 	pfnmap_setup_cachemode_pfn(pfn, &pgprot);
 
@@ -2262,7 +2260,7 @@ static inline bool can_change_pmd_writable(struct vm_area_struct *vma,
 {
 	struct page *page;
 
-	if (WARN_ON_ONCE(!(vma->vm_flags & VM_WRITE)))
+	if (WARN_ON_ONCE(!vma_test(vma, VMA_WRITE_BIT)))
 		return false;
 
 	/* Don't touch entries that are not even readable (NUMA hinting). */
@@ -2277,7 +2275,7 @@ static inline bool can_change_pmd_writable(struct vm_area_struct *vma,
 	if (userfaultfd_huge_pmd_wp(vma, pmd))
 		return false;
 
-	if (!(vma->vm_flags & VM_SHARED)) {
+	if (!vma_test(vma, VMA_SHARED_BIT)) {
 		/* See can_change_pte_writable(). */
 		page = vm_normal_page_pmd(vma, addr, pmd);
 		return page && PageAnon(page) && PageAnonExclusive(page);
@@ -3568,7 +3566,8 @@ static bool __discard_anon_folio_pmd_locked(struct vm_area_struct *vma,
 
 	if (pmd_dirty(orig_pmd))
 		folio_set_dirty(folio);
-	if (folio_test_dirty(folio) && !(vma->vm_flags & VM_DROPPABLE)) {
+	if (folio_test_dirty(folio) &&
+	    !vma_test_single_mask(vma, VMA_DROPPABLE)) {
 		folio_set_swapbacked(folio);
 		return false;
 	}
@@ -3600,7 +3599,8 @@ static bool __discard_anon_folio_pmd_locked(struct vm_area_struct *vma,
 	 */
 	if (pmd_dirty(orig_pmd))
 		folio_set_dirty(folio);
-	if (folio_test_dirty(folio) && !(vma->vm_flags & VM_DROPPABLE)) {
+	if (folio_test_dirty(folio) &&
+	    !vma_test_single_mask(vma, VMA_DROPPABLE)) {
 		folio_set_swapbacked(folio);
 		set_pmd_at(mm, addr, pmdp, orig_pmd);
 		return false;
@@ -3614,7 +3614,7 @@ static bool __discard_anon_folio_pmd_locked(struct vm_area_struct *vma,
 	folio_remove_rmap_pmd(folio, pmd_page(orig_pmd), vma);
 	zap_deposited_table(mm, pmdp);
 	add_mm_counter(mm, MM_ANONPAGES, -HPAGE_PMD_NR);
-	if (vma->vm_flags & VM_LOCKED)
+	if (vma_test(vma, VMA_LOCKED_BIT))
 		mlock_drain_local();
 	folio_put(folio);
 
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 0d3bd9e23613..a2c7c6a0768d 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -640,7 +640,8 @@ static enum scan_result __collapse_huge_page_isolate(struct vm_area_struct *vma,
 		 * If the vma has the VM_DROPPABLE flag, the collapse will
 		 * preserve the lazyfree property without needing to skip.
 		 */
-		if (cc->policy.anon_skip_lazyfree && !(vma->vm_flags & VM_DROPPABLE) &&
+		if (cc->policy.anon_skip_lazyfree &&
+		    !vma_test_single_mask(vma, VMA_DROPPABLE) &&
 		    folio_test_lazyfree(folio) && !pte_dirty(pteval)) {
 			result = SCAN_PAGE_LAZYFREE;
 			goto out;
@@ -1683,7 +1684,8 @@ static enum scan_result collapse_scan_anon(struct vm_area_struct *vma,
 		 * If the vma has the VM_DROPPABLE flag, the collapse will
 		 * preserve the lazyfree property without needing to skip.
 		 */
-		if (cc->policy.anon_skip_lazyfree && !(vma->vm_flags & VM_DROPPABLE) &&
+		if (cc->policy.anon_skip_lazyfree &&
+		    !vma_test_single_mask(vma, VMA_DROPPABLE) &&
 		    folio_test_lazyfree(folio) && !pte_dirty(pteval)) {
 			result = SCAN_PAGE_LAZYFREE;
 			failed_pfn = folio_pfn(folio);
@@ -1948,7 +1950,7 @@ static enum scan_result try_collapse_pte_mapped_thp(struct mm_struct *mm, unsign
 	 * So page lock of folio does not protect from it, so we must not drop
 	 * ptl before pgt_pmd is removed, so uffd private needs pml taken now.
 	 */
-	if (userfaultfd_armed(vma) && !(vma->vm_flags & VM_SHARED))
+	if (userfaultfd_armed(vma) && !vma_test(vma, VMA_SHARED_BIT))
 		pml = pmd_lock(mm, pmd);
 
 	start_pte = pte_offset_map_rw_nolock(mm, pmd, haddr, &pgt_pmd, &ptl);

-- 
2.56.0