2022-12-08 20:57:53

by Vishal Moola

Subject: [PATCH v3 1/4] mm/memory: Add vm_normal_folio()

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.

Signed-off-by: Vishal Moola (Oracle) <[email protected]>
---
include/linux/mm.h | 2 ++
mm/memory.c | 10 ++++++++++
2 files changed, 12 insertions(+)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 8bbcccbc5565..626ae0757bd3 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1860,6 +1860,8 @@ 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 f88c351aecd4..1247c19c516c 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -672,6 +672,16 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
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)
--
2.38.1

2022-12-08 21:03:23

by Matthew Wilcox

Subject: Re: [PATCH v3 1/4] mm/memory: Add vm_normal_folio()

On Thu, Dec 08, 2022 at 12:35:00PM -0800, Vishal Moola (Oracle) wrote:
> 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.
>
> Signed-off-by: Vishal Moola (Oracle) <[email protected]>

Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>