[PATCH v5 4/6] userfaultfd: convert mfill_atomic_hugetlb() to use a folio

Peng Zhang
2023-03-31T09:42:15Z

From: ZhangPeng <zhangpeng362@huawei.com>

Convert hugetlb_mfill_atomic_pte() to take in a folio pointer instead of
a page pointer. Convert mfill_atomic_hugetlb() to use a folio.

Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
---
include/linux/hugetlb.h | 4 ++--
mm/hugetlb.c | 26 +++++++++++++-------------
mm/userfaultfd.c | 16 ++++++++--------
3 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 2a758bcd6719..28703fe22386 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -163,7 +163,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
unsigned long dst_addr,
unsigned long src_addr,
uffd_flags_t flags,
- struct page **pagep);
+ struct folio **foliop);
#endif /* CONFIG_USERFAULTFD */
bool hugetlb_reserve_pages(struct inode *inode, long from, long to,
struct vm_area_struct *vma,
@@ -397,7 +397,7 @@ static inline int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
unsigned long dst_addr,
unsigned long src_addr,
uffd_flags_t flags,
- struct page **pagep)
+ struct folio **foliop)
{
BUG();
return 0;
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index aade1b513474..c88f856ec2e2 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -6178,7 +6178,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
unsigned long dst_addr,
unsigned long src_addr,
uffd_flags_t flags,
- struct page **pagep)
+ struct folio **foliop)
{
struct mm_struct *dst_mm = dst_vma->vm_mm;
bool is_continue = uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE);
@@ -6201,8 +6201,8 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
if (IS_ERR(folio))
goto out;
folio_in_pagecache = true;
- } else if (!*pagep) {
- /* If a page already exists, then it's UFFDIO_COPY for
+ } else if (!*foliop) {
+ /* If a folio already exists, then it's UFFDIO_COPY for
* a non-missing case. Return -EEXIST.
*/
if (vm_shared &&
@@ -6237,33 +6237,33 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
ret = -ENOMEM;
goto out;
}
- *pagep = &folio->page;
- /* Set the outparam pagep and return to the caller to
+ *foliop = folio;
+ /* Set the outparam foliop and return to the caller to
* copy the contents outside the lock. Don't free the
- * page.
+ * folio.
*/
goto out;
}
} else {
if (vm_shared &&
hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) {
- put_page(*pagep);
+ folio_put(*foliop);
ret = -EEXIST;
- *pagep = NULL;
+ *foliop = NULL;
goto out;
}

folio = alloc_hugetlb_folio(dst_vma, dst_addr, 0);
if (IS_ERR(folio)) {
- put_page(*pagep);
+ folio_put(*foliop);
ret = -ENOMEM;
- *pagep = NULL;
+ *foliop = NULL;
goto out;
}
- copy_user_huge_page(&folio->page, *pagep, dst_addr, dst_vma,
+ copy_user_huge_page(&folio->page, &(*foliop)->page, dst_addr, dst_vma,
pages_per_huge_page(h));
- put_page(*pagep);
- *pagep = NULL;
+ folio_put(*foliop);
+ *foliop = NULL;
}

/*
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 78fed9003cf7..f9ebaa079a6a 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -322,7 +322,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb(
pte_t *dst_pte;
unsigned long src_addr, dst_addr;
long copied;
- struct page *page;
+ struct folio *folio;
unsigned long vma_hpagesize;
pgoff_t idx;
u32 hash;
@@ -342,7 +342,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb(
src_addr = src_start;
dst_addr = dst_start;
copied = 0;
- page = NULL;
+ folio = NULL;
vma_hpagesize = vma_kernel_pagesize(dst_vma);

/*
@@ -411,7 +411,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb(
}

err = hugetlb_mfill_atomic_pte(dst_pte, dst_vma, dst_addr,
- src_addr, flags, &page);
+ src_addr, flags, &folio);

hugetlb_vma_unlock_read(dst_vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
@@ -420,9 +420,9 @@ static __always_inline ssize_t mfill_atomic_hugetlb(

if (unlikely(err == -ENOENT)) {
mmap_read_unlock(dst_mm);
- BUG_ON(!page);
+ BUG_ON(!folio);

- err = copy_folio_from_user(page_folio(page),
+ err = copy_folio_from_user(folio,
(const void __user *)src_addr, true);
if (unlikely(err)) {
err = -EFAULT;
@@ -433,7 +433,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb(
dst_vma = NULL;
goto retry;
} else
- BUG_ON(page);
+ BUG_ON(folio);

if (!err) {
dst_addr += vma_hpagesize;
@@ -450,8 +450,8 @@ static __always_inline ssize_t mfill_atomic_hugetlb(
out_unlock:
mmap_read_unlock(dst_mm);
out:
- if (page)
- put_page(page);
+ if (folio)
+ folio_put(folio);
BUG_ON(copied < 0);
BUG_ON(err > 0);
BUG_ON(!copied && !err);
--
2.25.1