From nobody Thu Dec 18 15:24:26 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F7C7C4167B for ; Tue, 28 Nov 2023 15:53:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346479AbjK1Pw5 (ORCPT ); Tue, 28 Nov 2023 10:52:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346381AbjK1Pwr (ORCPT ); Tue, 28 Nov 2023 10:52:47 -0500 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B045010CA; Tue, 28 Nov 2023 07:52:52 -0800 (PST) Received: from pps.filterd (m0353727.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3ASFqCmn025863; Tue, 28 Nov 2023 15:52:41 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=mAMWAmx4tTbSFhnG6X+oeskqJ2cVVuibj42I4REYo6w=; b=Iv1BKINlJnjhQCioZR2zg1N8UHxJUloCT/s/MTX8CSLCFyQc1zCdNXrstOAdHlXXaWFv yUpDrsDDw9ufWbZhOt72QqcvbbxYiF7iyXjLl6po22zKS3Op107ST/o1uGYUxZDudjI0 mgie6ngJ3qAACu9/fuQGcF+6wiOhnfd09jeb9Ndvw5BMbkz/KgmxFHOhIZYwZMIzebzP KDj1zHjTJXaKCz+wv2ZHOgXucXcK45fqfAyvX9OKgo1wtrJxMnGXlB+NC0CsixnvTNFw IVftl62HLAKO7TTwjcjZQipedtK5C8VN7W2cRRB5kTpFEkE26cU7inZyfPClEJynIcJh iw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3unk7n00f5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 28 Nov 2023 15:52:40 +0000 Received: from m0353727.ppops.net (m0353727.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3ASFqegg027840; Tue, 28 Nov 2023 15:52:40 GMT Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3unk7n00ea-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 28 Nov 2023 15:52:40 +0000 Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 3ASDS1w4031065; Tue, 28 Nov 2023 15:52:38 GMT Received: from smtprelay06.fra02v.mail.ibm.com ([9.218.2.230]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 3uku8t0y8c-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 28 Nov 2023 15:52:38 +0000 Received: from smtpav05.fra02v.mail.ibm.com (smtpav05.fra02v.mail.ibm.com [10.20.54.104]) by smtprelay06.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 3ASFqa4L43188918 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 28 Nov 2023 15:52:36 GMT Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 04A5920040; Tue, 28 Nov 2023 15:52:36 +0000 (GMT) Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9E3422004B; Tue, 28 Nov 2023 15:52:35 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by smtpav05.fra02v.mail.ibm.com (Postfix) with ESMTP; Tue, 28 Nov 2023 15:52:35 +0000 (GMT) From: Sumanth Korikkar To: linux-mm , Andrew Morton , David Hildenbrand Cc: Oscar Salvador , Michal Hocko , "Aneesh Kumar K.V" , Anshuman Khandual , Gerald Schaefer , Alexander Gordeev , Heiko Carstens , Vasily Gorbik , linux-s390 , LKML Subject: [PATCH v5 4/5] s390/mm: implement MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiers Date: Tue, 28 Nov 2023 16:52:26 +0100 Message-Id: <20231128155227.1315063-5-sumanthk@linux.ibm.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20231128155227.1315063-1-sumanthk@linux.ibm.com> References: <20231128155227.1315063-1-sumanthk@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: IvgOVkupz2u_q2vxVUHixm_jiZzz_VAT X-Proofpoint-GUID: xthJt4AmJ-iVsHgqcPT9Eh_Rh0ZkO93N X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-28_18,2023-11-27_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 mlxlogscore=999 impostorscore=0 suspectscore=0 mlxscore=0 clxscore=1015 adultscore=0 bulkscore=0 priorityscore=1501 spamscore=0 phishscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311280127 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" MEM_PREPARE_ONLINE memory notifier makes memory block physical accessible via sclp assign command. The notifier ensures self-contained memory maps are accessible and hence enabling the "memmap on memory" on s390. MEM_FINISH_OFFLINE memory notifier shifts the memory block to an inaccessible state via sclp unassign command. Implementation considerations: * When MHP_MEMMAP_ON_MEMORY is disabled, the system retains the old behavior. This means the memory map is allocated from default memory. * If MACHINE_HAS_EDAT1 is unavailable, MHP_MEMMAP_ON_MEMORY is automatically disabled. This ensures that vmemmap pagetables do not consume additional memory from the default memory allocator. * The MEM_GOING_ONLINE notifier has been modified to perform no operation, as MEM_PREPARE_ONLINE already executes the sclp assign command. * The MEM_CANCEL_ONLINE/MEM_OFFLINE notifier now performs no operation, as MEM_FINISH_OFFLINE already executes the sclp unassign command. Reviewed-by: Gerald Schaefer Reviewed-by: David Hildenbrand Signed-off-by: Sumanth Korikkar --- drivers/s390/char/sclp_cmd.c | 41 ++++++++++++++++++++++++++++++------ 1 file changed, 35 insertions(+), 6 deletions(-) diff --git a/drivers/s390/char/sclp_cmd.c b/drivers/s390/char/sclp_cmd.c index 355e63e44e95..7815e9bea69a 100644 --- a/drivers/s390/char/sclp_cmd.c +++ b/drivers/s390/char/sclp_cmd.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -26,6 +27,7 @@ #include #include #include +#include =20 #include "sclp.h" =20 @@ -340,13 +342,38 @@ static int sclp_mem_notifier(struct notifier_block *n= b, if (contains_standby_increment(start, start + size)) rc =3D -EPERM; break; - case MEM_GOING_ONLINE: + case MEM_PREPARE_ONLINE: + /* + * Access the altmap_start_pfn and altmap_nr_pages fields + * within the struct memory_notify specifically when dealing + * with only MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiers. + * + * When altmap is in use, take the specified memory range + * online, which includes the altmap. + */ + if (arg->altmap_nr_pages) { + start =3D PFN_PHYS(arg->altmap_start_pfn); + size +=3D PFN_PHYS(arg->altmap_nr_pages); + } rc =3D sclp_mem_change_state(start, size, 1); + if (rc || !arg->altmap_nr_pages) + break; + /* + * Set CMMA state to nodat here, since the struct page memory + * at the beginning of the memory block will not go through the + * buddy allocator later. + */ + __arch_set_page_nodat((void *)__va(start), arg->altmap_nr_pages); break; - case MEM_CANCEL_ONLINE: - sclp_mem_change_state(start, size, 0); - break; - case MEM_OFFLINE: + case MEM_FINISH_OFFLINE: + /* + * When altmap is in use, take the specified memory range + * offline, which includes the altmap. + */ + if (arg->altmap_nr_pages) { + start =3D PFN_PHYS(arg->altmap_start_pfn); + size +=3D PFN_PHYS(arg->altmap_nr_pages); + } sclp_mem_change_state(start, size, 0); break; default: @@ -397,7 +424,9 @@ static void __init add_memory_merged(u16 rn) if (!size) goto skip_add; for (addr =3D start; addr < start + size; addr +=3D block_size) - add_memory(0, addr, block_size, MHP_NONE); + add_memory(0, addr, block_size, + MACHINE_HAS_EDAT1 ? + MHP_MEMMAP_ON_MEMORY | MHP_OFFLINE_INACCESSIBLE : MHP_NONE); skip_add: first_rn =3D rn; num =3D 1; --=20 2.40.1