From nobody Wed Dec 17 19:04:13 2025 Received: from out30-101.freemail.mail.aliyun.com (out30-101.freemail.mail.aliyun.com [115.124.30.101]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CE1601420A6 for ; Mon, 6 May 2024 08:46:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.101 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714985212; cv=none; b=pKEkWJs4gdYXEA1NY0VBvi376OZtjzOVkpom3j98AzTBvTAgJkYEdrj617645G9mlmLHMlgB7EXYMwvfC+TBiJCzYT1GHLjT3dFNBHuO5xSacRnLyTg2ELByKdRzu5SDx5kH416IQf7rWWicaGgZLtsro8KFdOsW8+mhSvHDr+c= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714985212; c=relaxed/simple; bh=TtEvthxzqcH6fibOTrZH8nZvm8Cacr0Qx1M3RVs4Sq8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=kiSTuLvQvKid/P8R/UjLKIUs7OC0NsQj09MQSCMMg6pGPFbuZigDeUpvVDdxTCB5nXSKE3t0unBp/GuWOHWLQyvzCXZr7++iie4LNrjXDKg7nHwnq4f66/bB1IjQiUKcjfmtL04UUIdQYWf9DyxxVvYC5umLajgjlKvCjg7POoY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=VaC/kRe1; arc=none smtp.client-ip=115.124.30.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="VaC/kRe1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1714985207; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=zEr/Eu5mgqpEki8XSyTh3V+LovJcAoeI3KW1/F4hkgg=; b=VaC/kRe1uXXZZhETUNZOyPdATJLv9wdN9iawFkKUMls4e7lUzINH4uM0PxZENld2U6PYzjxI7QUSAKP0Az7SdKF6WA6ea1z1iMbU4a+R0Od02k2s4ZvGl6Pkke/GkaIFIoCl7ij1a0NoZcbMhyA1FELXiH5ihqdVzv3+OtK4feY= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R101e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033022160150;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=14;SR=0;TI=SMTPD_---0W5weiKG_1714985205; Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0W5weiKG_1714985205) by smtp.aliyun-inc.com; Mon, 06 May 2024 16:46:46 +0800 From: Baolin Wang To: akpm@linux-foundation.org, hughd@google.com Cc: willy@infradead.org, david@redhat.com, ioworker0@gmail.com, wangkefeng.wang@huawei.com, ying.huang@intel.com, 21cnbao@gmail.com, ryan.roberts@arm.com, shy828301@gmail.com, ziy@nvidia.com, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/8] mm: memory: extend finish_fault() to support large folio Date: Mon, 6 May 2024 16:46:26 +0800 Message-Id: X-Mailer: git-send-email 2.39.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add large folio mapping establishment support for finish_fault() as a prepa= ration, to support multi-size THP allocation of anonymous shmem pages in the follow= ing patches. Signed-off-by: Baolin Wang --- mm/memory.c | 43 +++++++++++++++++++++++++++++++++---------- 1 file changed, 33 insertions(+), 10 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index eea6e4984eae..936377220b77 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4747,9 +4747,12 @@ vm_fault_t finish_fault(struct vm_fault *vmf) { struct vm_area_struct *vma =3D vmf->vma; struct page *page; + struct folio *folio; vm_fault_t ret; bool is_cow =3D (vmf->flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED); + int type, nr_pages, i; + unsigned long addr =3D vmf->address; =20 /* Did we COW the page? */ if (is_cow) @@ -4780,24 +4783,44 @@ vm_fault_t finish_fault(struct vm_fault *vmf) return VM_FAULT_OOM; } =20 + folio =3D page_folio(page); + nr_pages =3D folio_nr_pages(folio); + + if (unlikely(userfaultfd_armed(vma))) { + nr_pages =3D 1; + } else if (nr_pages > 1) { + unsigned long start =3D ALIGN_DOWN(vmf->address, nr_pages * PAGE_SIZE); + unsigned long end =3D start + nr_pages * PAGE_SIZE; + + /* In case the folio size in page cache beyond the VMA limits. */ + addr =3D max(start, vma->vm_start); + nr_pages =3D (min(end, vma->vm_end) - addr) >> PAGE_SHIFT; + + page =3D folio_page(folio, (addr - start) >> PAGE_SHIFT); + } vmf->pte =3D pte_offset_map_lock(vma->vm_mm, vmf->pmd, - vmf->address, &vmf->ptl); + addr, &vmf->ptl); if (!vmf->pte) return VM_FAULT_NOPAGE; =20 /* Re-check under ptl */ - if (likely(!vmf_pte_changed(vmf))) { - struct folio *folio =3D page_folio(page); - int type =3D is_cow ? MM_ANONPAGES : mm_counter_file(folio); - - set_pte_range(vmf, folio, page, 1, vmf->address); - add_mm_counter(vma->vm_mm, type, 1); - ret =3D 0; - } else { - update_mmu_tlb(vma, vmf->address, vmf->pte); + if (nr_pages =3D=3D 1 && unlikely(vmf_pte_changed(vmf))) { + update_mmu_tlb(vma, addr, vmf->pte); + ret =3D VM_FAULT_NOPAGE; + goto unlock; + } else if (nr_pages > 1 && !pte_range_none(vmf->pte, nr_pages)) { + for (i =3D 0; i < nr_pages; i++) + update_mmu_tlb(vma, addr + PAGE_SIZE * i, vmf->pte + i); ret =3D VM_FAULT_NOPAGE; + goto unlock; } =20 + set_pte_range(vmf, folio, page, nr_pages, addr); + type =3D is_cow ? MM_ANONPAGES : mm_counter_file(folio); + add_mm_counter(vma->vm_mm, type, nr_pages); + ret =3D 0; + +unlock: pte_unmap_unlock(vmf->pte, vmf->ptl); return ret; } --=20 2.39.3