The patch titled Subject: userfaultfd: convert mfill_atomic_pte_copy() to use a folio has been added to the -mm mm-unstable branch. Its filename is userfaultfd-convert-mfill_atomic_pte_copy-to-use-a-folio.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/userfaultfd-convert-mfill_atomic_pte_copy-to-use-a-folio.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: ZhangPeng <zhangpeng362@xxxxxxxxxx> Subject: userfaultfd: convert mfill_atomic_pte_copy() to use a folio Date: Fri, 31 Mar 2023 17:39:32 +0800 Patch series "userfaultfd: convert userfaultfd functions to use folios", v5. This series converts several userfaultfd functions to use folios. This patch (of 6): Call vma_alloc_folio() directly instead of alloc_page_vma() and convert page_kaddr to kaddr in mfill_atomic_pte_copy(). Removes several calls to compound_head(). Link: https://lkml.kernel.org/r/20230331093937.945725-1-zhangpeng362@xxxxxxxxxx Link: https://lkml.kernel.org/r/20230331093937.945725-2-zhangpeng362@xxxxxxxxxx Signed-off-by: ZhangPeng <zhangpeng362@xxxxxxxxxx> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> Cc: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Muchun Song <muchun.song@xxxxxxxxx> Cc: Nanyong Sun <sunnanyong@xxxxxxxxxx> Cc: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/userfaultfd.c | 33 +++++++++++++++++---------------- 1 file changed, 17 insertions(+), 16 deletions(-) --- a/mm/userfaultfd.c~userfaultfd-convert-mfill_atomic_pte_copy-to-use-a-folio +++ a/mm/userfaultfd.c @@ -135,17 +135,18 @@ static int mfill_atomic_pte_copy(pmd_t * uffd_flags_t flags, struct page **pagep) { - void *page_kaddr; + void *kaddr; int ret; - struct page *page; + struct folio *folio; if (!*pagep) { ret = -ENOMEM; - page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, dst_vma, dst_addr); - if (!page) + folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0, dst_vma, + dst_addr, false); + if (!folio) goto out; - page_kaddr = kmap_local_page(page); + kaddr = kmap_local_folio(folio, 0); /* * The read mmap_lock is held here. Despite the * mmap_lock being read recursive a deadlock is still @@ -162,45 +163,45 @@ static int mfill_atomic_pte_copy(pmd_t * * and retry the copy outside the mmap_lock. */ pagefault_disable(); - ret = copy_from_user(page_kaddr, - (const void __user *) src_addr, + ret = copy_from_user(kaddr, (const void __user *) src_addr, PAGE_SIZE); pagefault_enable(); - kunmap_local(page_kaddr); + kunmap_local(kaddr); /* fallback to copy_from_user outside mmap_lock */ if (unlikely(ret)) { ret = -ENOENT; - *pagep = page; + *pagep = &folio->page; /* don't free the page */ goto out; } - flush_dcache_page(page); + flush_dcache_folio(folio); } else { - page = *pagep; + folio = page_folio(*pagep); + VM_BUG_ON_FOLIO(folio_test_large(folio), folio); *pagep = NULL; } /* - * The memory barrier inside __SetPageUptodate makes sure that + * The memory barrier inside __folio_mark_uptodate makes sure that * preceding stores to the page contents become visible before * the set_pte_at() write. */ - __SetPageUptodate(page); + __folio_mark_uptodate(folio); ret = -ENOMEM; - if (mem_cgroup_charge(page_folio(page), dst_vma->vm_mm, GFP_KERNEL)) + if (mem_cgroup_charge(folio, dst_vma->vm_mm, GFP_KERNEL)) goto out_release; ret = mfill_atomic_install_pte(dst_pmd, dst_vma, dst_addr, - page, true, flags); + &folio->page, true, flags); if (ret) goto out_release; out: return ret; out_release: - put_page(page); + folio_put(folio); goto out; } _ Patches currently in -mm which might be from zhangpeng362@xxxxxxxxxx are userfaultfd-convert-mfill_atomic_pte_copy-to-use-a-folio.patch userfaultfd-use-kmap_local_page-in-copy_huge_page_from_user.patch userfaultfd-convert-copy_huge_page_from_user-to-copy_folio_from_user.patch userfaultfd-convert-mfill_atomic_hugetlb-to-use-a-folio.patch mm-convert-copy_user_huge_page-to-copy_user_folio.patch userfaultfd-convert-mfill_atomic-to-use-a-folio.patch