mm: add folio_mk_pmd()

Removes five conversions from folio to page.  Also removes both callers of
mk_pmd() that aren't part of mk_huge_pmd(), getting us a step closer to
removing the confusion between mk_pmd(), mk_huge_pmd() and pmd_mkhuge().

Link: https://lkml.kernel.org/r/20250402181709.2386022-11-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Richard Weinberger <richard@nod.at>
Cc: <x86@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/dax.c b/fs/dax.c
index 6763034..5087ca3 100644 (file)
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1422,8 +1422,7 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
                pgtable_trans_huge_deposit(vma->vm_mm, vmf->pmd, pgtable);
                mm_inc_nr_ptes(vma->vm_mm);
        }
-       pmd_entry = mk_pmd(&zero_folio->page, vmf->vma->vm_page_prot);
-       pmd_entry = pmd_mkhuge(pmd_entry);
+       pmd_entry = folio_mk_pmd(zero_folio, vmf->vma->vm_page_prot);
        set_pmd_at(vmf->vma->vm_mm, pmd_addr, vmf->pmd, pmd_entry);
        spin_unlock(ptl);
        trace_dax_pmd_load_hole(inode, vmf, zero_folio, *entry);

diff --git a/include/linux/mm.h b/include/linux/mm.h
index cbad8c6..733dd71 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2024,7 +2024,24 @@ static inline pte_t folio_mk_pte(struct folio *folio, pgprot_t pgprot)
 {
        return pfn_pte(folio_pfn(folio), pgprot);
 }
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+/**
+ * folio_mk_pmd - Create a PMD for this folio
+ * @folio: The folio to create a PMD for
+ * @pgprot: The page protection bits to use
+ *
+ * Create a page table entry for the first page of this folio.
+ * This is suitable for passing to set_pmd_at().
+ *
+ * Return: A page table entry suitable for mapping this folio.
+ */
+static inline pmd_t folio_mk_pmd(struct folio *folio, pgprot_t pgprot)
+{
+       return pmd_mkhuge(pfn_pmd(folio_pfn(folio), pgprot));
+}
 #endif
+#endif /* CONFIG_MMU */
 
 static inline bool folio_has_pincount(const struct folio *folio)
 {

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 47d76d0..1cd9755 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1203,7 +1203,7 @@ static void map_anon_folio_pmd(struct folio *folio, pmd_t *pmd,
 {
        pmd_t entry;
 
-       entry = mk_huge_pmd(&folio->page, vma->vm_page_prot);
+       entry = folio_mk_pmd(folio, vma->vm_page_prot);
        entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
        folio_add_new_anon_rmap(folio, vma, haddr, RMAP_EXCLUSIVE);
        folio_add_lru_vma(folio, vma);
@@ -1309,8 +1309,7 @@ static void set_huge_zero_folio(pgtable_t pgtable, struct mm_struct *mm,
                struct folio *zero_folio)
 {
        pmd_t entry;
-       entry = mk_pmd(&zero_folio->page, vma->vm_page_prot);
-       entry = pmd_mkhuge(entry);
+       entry = folio_mk_pmd(zero_folio, vma->vm_page_prot);
        pgtable_trans_huge_deposit(mm, pmd, pgtable);
        set_pmd_at(mm, haddr, pmd, entry);
        mm_inc_nr_ptes(mm);
@@ -2653,12 +2652,12 @@ int move_pages_huge_pmd(struct mm_struct *mm, pmd_t *dst_pmd, pmd_t *src_pmd, pm
                folio_move_anon_rmap(src_folio, dst_vma);
                src_folio->index = linear_page_index(dst_vma, dst_addr);
 
-               _dst_pmd = mk_huge_pmd(&src_folio->page, dst_vma->vm_page_prot);
+               _dst_pmd = folio_mk_pmd(src_folio, dst_vma->vm_page_prot);
                /* Follow mremap() behavior and treat the entry dirty after the move */
                _dst_pmd = pmd_mkwrite(pmd_mkdirty(_dst_pmd), dst_vma);
        } else {
                src_pmdval = pmdp_huge_clear_flush(src_vma, src_addr, src_pmd);
-               _dst_pmd = mk_huge_pmd(src_page, dst_vma->vm_page_prot);
+               _dst_pmd = folio_mk_pmd(src_folio, dst_vma->vm_page_prot);
        }
        set_pmd_at(mm, dst_addr, dst_pmd, _dst_pmd);
 
@@ -4680,7 +4679,7 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new)
 
        entry = pmd_to_swp_entry(*pvmw->pmd);
        folio_get(folio);
-       pmde = mk_huge_pmd(new, READ_ONCE(vma->vm_page_prot));
+       pmde = folio_mk_pmd(folio, READ_ONCE(vma->vm_page_prot));
        if (pmd_swp_soft_dirty(*pvmw->pmd))
                pmde = pmd_mksoft_dirty(pmde);
        if (is_writable_migration_entry(entry))

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index cc945c6..b8838ba 100644 (file)
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1239,7 +1239,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address,
        __folio_mark_uptodate(folio);
        pgtable = pmd_pgtable(_pmd);
 
-       _pmd = mk_huge_pmd(&folio->page, vma->vm_page_prot);
+       _pmd = folio_mk_pmd(folio, vma->vm_page_prot);
        _pmd = maybe_pmd_mkwrite(pmd_mkdirty(_pmd), vma);
 
        spin_lock(pmd_ptl);

diff --git a/mm/memory.c b/mm/memory.c
index a9e6319..86e7e66 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -5188,7 +5188,7 @@ vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
 
        flush_icache_pages(vma, page, HPAGE_PMD_NR);
 
-       entry = mk_huge_pmd(page, vma->vm_page_prot);
+       entry = folio_mk_pmd(folio, vma->vm_page_prot);
        if (write)
                entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);