[PATCH 8/9] mm/hugetlb: convert hugetlb_wp() to take in a folio

From: Sidhartha Kumar
Date: Thu Jan 19 2023 - 16:23:53 EST


Change the pagecache_page argument of hugetlb_wp to pagecache_folio.
Replaces a call to find_lock_page() with filemap_lock_folio().

Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
---
mm/hugetlb.c | 34 +++++++++++++++++-----------------
1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 4ab3eda6db18..20127271b64c 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5472,7 +5472,7 @@ static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
*/
static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pte_t *ptep, unsigned int flags,
- struct page *pagecache_page, spinlock_t *ptl)
+ struct folio *pagecache_folio, spinlock_t *ptl)
{
const bool unshare = flags & FAULT_FLAG_UNSHARE;
pte_t pte;
@@ -5529,7 +5529,7 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma,
* of the full address range.
*/
if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) &&
- old_page != pagecache_page)
+ page_folio(old_page) != pagecache_folio)
outside_reserve = 1;

get_page(old_page);
@@ -5923,7 +5923,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
hugetlb_count_add(pages_per_huge_page(h), mm);
if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
/* Optimization, do the COW without a second fault */
- ret = hugetlb_wp(mm, vma, address, ptep, flags, &folio->page, ptl);
+ ret = hugetlb_wp(mm, vma, address, ptep, flags, folio, ptl);
}

spin_unlock(ptl);
@@ -5986,7 +5986,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
u32 hash;
pgoff_t idx;
struct page *page = NULL;
- struct page *pagecache_page = NULL;
+ struct folio *pagecache_folio = NULL;
struct hstate *h = hstate_vma(vma);
struct address_space *mapping;
int need_wait_lock = 0;
@@ -6068,7 +6068,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
/* Just decrements count, does not deallocate */
vma_end_reservation(h, vma, haddr);

- pagecache_page = find_lock_page(mapping, idx);
+ pagecache_folio = filemap_lock_folio(mapping, idx);
}

ptl = huge_pte_lock(h, mm, ptep);
@@ -6088,9 +6088,9 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
};

spin_unlock(ptl);
- if (pagecache_page) {
- unlock_page(pagecache_page);
- put_page(pagecache_page);
+ if (pagecache_folio) {
+ folio_unlock(pagecache_folio);
+ folio_put(pagecache_folio);
}
hugetlb_vma_unlock_read(vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
@@ -6099,22 +6099,22 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,

/*
* hugetlb_wp() requires page locks of pte_page(entry) and
- * pagecache_page, so here we need take the former one
- * when page != pagecache_page or !pagecache_page.
+ * pagecache_folio, so here we need take the former one
+ * when page != pagecache_folio or !pagecache_folio.
*/
page = pte_page(entry);
- if (page != pagecache_page)
+ if (page_folio(page) != pagecache_folio)
if (!trylock_page(page)) {
need_wait_lock = 1;
goto out_ptl;
}

- get_page(page);
+ folio_get(pagecache_folio);

if (flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) {
if (!huge_pte_write(entry)) {
ret = hugetlb_wp(mm, vma, address, ptep, flags,
- pagecache_page, ptl);
+ pagecache_folio, ptl);
goto out_put_page;
} else if (likely(flags & FAULT_FLAG_WRITE)) {
entry = huge_pte_mkdirty(entry);
@@ -6125,15 +6125,15 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
flags & FAULT_FLAG_WRITE))
update_mmu_cache(vma, haddr, ptep);
out_put_page:
- if (page != pagecache_page)
+ if (page_folio(page) != pagecache_folio)
unlock_page(page);
put_page(page);
out_ptl:
spin_unlock(ptl);

- if (pagecache_page) {
- unlock_page(pagecache_page);
- put_page(pagecache_page);
+ if (pagecache_folio) {
+ folio_unlock(pagecache_folio);
+ folio_put(pagecache_folio);
}
out_mutex:
hugetlb_vma_unlock_read(vma);
--
2.39.0