mm/memory: add vm_normal_folio()

Patch series "Convert deactivate_page() to folio_deactivate()", v4.

Deactivate_page() has already been converted to use folios.  This patch
series modifies the callers of deactivate_page() to use folios.  It also
introduces vm_normal_folio() to assist with folio conversions, and
converts deactivate_page() to folio_deactivate() which takes in a folio.

This patch (of 4):

Introduce a wrapper function called vm_normal_folio().  This function
calls vm_normal_page() and returns the folio of the page found, or null if
no page is found.

This function allows callers to get a folio from a pte, which will
eventually allow them to completely replace their struct page variables
with struct folio instead.

Link: https://lkml.kernel.org/r/20221221180848.20774-1-vishal.moola@gmail.com
Link: https://lkml.kernel.org/r/20221221180848.20774-2-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 253b2d7489e6546a5b7557ee8e29ff13cd386b0f..8e14183dfc58f683ef4017540b942dde477c16bd 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1968,6 +1968,8 @@ static inline bool can_do_mlock(void) { return false; }
 extern int user_shm_lock(size_t, struct ucounts *);
 extern void user_shm_unlock(size_t, struct ucounts *);
 
+struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr,
+                            pte_t pte);
 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
                             pte_t pte);
 struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,

diff --git a/mm/memory.c b/mm/memory.c
index ca490596b36f5d761fe58b02061db96ea24b8583..1598051a2a24ced2c62b6f1c7c461a20c118c9c4 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -625,6 +625,16 @@ out:
        return pfn_to_page(pfn);
 }
 
+struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr,
+                           pte_t pte)
+{
+       struct page *page = vm_normal_page(vma, addr, pte);
+
+       if (page)
+               return page_folio(page);
+       return NULL;
+}
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
                                pmd_t pmd)