From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0AEEDC35247 for ; Mon, 3 Feb 2020 13:20:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E032820658 for ; Mon, 3 Feb 2020 13:20:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728211AbgBCNUE (ORCPT ); Mon, 3 Feb 2020 08:20:04 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:34904 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726913AbgBCNUD (ORCPT ); Mon, 3 Feb 2020 08:20:03 -0500 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 013DGKFf036958 for ; Mon, 3 Feb 2020 08:20:02 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2xxm8kg4tn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 03 Feb 2020 08:20:02 -0500 Received: from m0098410.ppops.net (m0098410.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 013DHYQm061561 for ; Mon, 3 Feb 2020 08:20:02 -0500 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0a-001b2d01.pphosted.com with ESMTP id 2xxm8kg4sx-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 03 Feb 2020 08:20:02 -0500 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 013DHKeG010827; Mon, 3 Feb 2020 13:20:01 GMT Received: from b01cxnp22033.gho.pok.ibm.com (b01cxnp22033.gho.pok.ibm.com [9.57.198.23]) by ppma03dal.us.ibm.com with ESMTP id 2xw0y758yg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 03 Feb 2020 13:20:01 +0000 Received: from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com [9.57.199.106]) by b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 013DJwQq36766058 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 3 Feb 2020 13:19:59 GMT Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 934DF2805E; Mon, 3 Feb 2020 13:19:58 +0000 (GMT) Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8E2462806F; Mon, 3 Feb 2020 13:19:58 +0000 (GMT) Received: from localhost.localdomain (unknown [9.114.17.106]) by b01ledav001.gho.pok.ibm.com (Postfix) with ESMTP; Mon, 3 Feb 2020 13:19:58 +0000 (GMT) From: Christian Borntraeger To: Christian Borntraeger , Janosch Frank Cc: KVM , Cornelia Huck , David Hildenbrand , Thomas Huth , Ulrich Weigand , Claudio Imbrenda , Andrea Arcangeli Subject: [RFCv2 04/37] mm:gup/writeback: add callbacks for inaccessible pages Date: Mon, 3 Feb 2020 08:19:24 -0500 Message-Id: <20200203131957.383915-5-borntraeger@de.ibm.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20200203131957.383915-1-borntraeger@de.ibm.com> References: <20200203131957.383915-1-borntraeger@de.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-02-03_04:2020-02-02,2020-02-03 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 lowpriorityscore=0 suspectscore=2 spamscore=0 malwarescore=0 phishscore=0 clxscore=1015 priorityscore=1501 bulkscore=0 mlxlogscore=893 adultscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1911200001 definitions=main-2002030099 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Claudio Imbrenda With the introduction of protected KVM guests on s390 there is now a concept of inaccessible pages. These pages need to be made accessible before the host can access them. While cpu accesses will trigger a fault that can be resolved, I/O accesses will just fail. We need to add a callback into architecture code for places that will do I/Oi, namely when writeback is started or when a page reference is taken. Signed-off-by: Claudio Imbrenda --- include/linux/gfp.h | 6 ++++++ mm/gup.c | 2 ++ mm/page-writeback.c | 1 + 3 files changed, 9 insertions(+) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index e5b817cb86e7..be2754841369 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -485,6 +485,12 @@ static inline void arch_free_page(struct page *page, int order) { } #ifndef HAVE_ARCH_ALLOC_PAGE static inline void arch_alloc_page(struct page *page, int order) { } #endif +#ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE +static inline int arch_make_page_accessible(struct page *page) +{ + return 0; +} +#endif struct page * __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, diff --git a/mm/gup.c b/mm/gup.c index 7646bf993b25..a01262cd2821 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -257,6 +257,7 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, page = ERR_PTR(-ENOMEM); goto out; } + arch_make_page_accessible(page); } if (flags & FOLL_TOUCH) { if ((flags & FOLL_WRITE) && @@ -1870,6 +1871,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, VM_BUG_ON_PAGE(compound_head(page) != head, page); + arch_make_page_accessible(page); SetPageReferenced(page); pages[*nr] = page; (*nr)++; diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 2caf780a42e7..0f0bd14571b1 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2806,6 +2806,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write) inc_lruvec_page_state(page, NR_WRITEBACK); inc_zone_page_state(page, NR_ZONE_WRITE_PENDING); } + arch_make_page_accessible(page); unlock_page_memcg(page); return ret; -- 2.24.0