From nobody Thu Apr 2 18:11:27 2026 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 632E5C6FA86 for ; Thu, 22 Sep 2022 09:53:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231207AbiIVJxX (ORCPT ); Thu, 22 Sep 2022 05:53:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229736AbiIVJxL (ORCPT ); Thu, 22 Sep 2022 05:53:11 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 572C2D4AB5; Thu, 22 Sep 2022 02:53:10 -0700 (PDT) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 28M9l6rl004094; Thu, 22 Sep 2022 09:52:48 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=iFPzyc+1zpfNBkQxlnUTKpOGKxYzWSgrTkAMFIFkP0M=; b=kXqoF+ylTtQKHUmiyTSfAD7BhHLNRXiHH74SETVPYLzop7Horzkku9llDA1Vvg6Ajo79 c34nTb+j7yX+k9jidex3lTUWBKi/aqG95raZXuQfltZ96g4soBGadq/386RdD6cdcZR3 pBi9kUIXfXU4CclFTIZ9y0v3IzROp8a/W8FauhA7vQb+A8X81qOOv3hpjx/Iy1gnEy6O d/3xn7QZR5YnoB22GO81MfNfFWa1FkL/AZP+tLaVNKq+2ecH49cerzYQgv84DcY0yDMR 1JoyWfa4tUL/eUg+Ei/jpXrsPbdp1xzuXTK2GlHqoZN7dpm7CgHPsjMjnPNvmy+P2zdD sA== Received: from ppma04fra.de.ibm.com (6a.4a.5195.ip4.static.sl-reverse.com [149.81.74.106]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3jrk3t4ejr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 22 Sep 2022 09:52:47 +0000 Received: from pps.filterd (ppma04fra.de.ibm.com [127.0.0.1]) by ppma04fra.de.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 28M9pICB031345; Thu, 22 Sep 2022 09:52:45 GMT Received: from b06avi18626390.portsmouth.uk.ibm.com (b06avi18626390.portsmouth.uk.ibm.com [9.149.26.192]) by ppma04fra.de.ibm.com with ESMTP id 3jn5v94u0b-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 22 Sep 2022 09:52:45 +0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 28M9mdx733620342 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 22 Sep 2022 09:48:39 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 311C44C04E; Thu, 22 Sep 2022 09:52:42 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B50D44C044; Thu, 22 Sep 2022 09:52:41 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 22 Sep 2022 09:52:41 +0000 (GMT) From: Niklas Schnelle To: Matthew Rosato , Pierre Morel , iommu@lists.linux.dev Cc: linux-s390@vger.kernel.org, borntraeger@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com, gerald.schaefer@linux.ibm.com, agordeev@linux.ibm.com, svens@linux.ibm.com, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, jgg@nvidia.com, linux-kernel@vger.kernel.org Subject: [PATCH v2 3/3] iommu/s390: Get rid of s390_domain_device Date: Thu, 22 Sep 2022 11:52:39 +0200 Message-Id: <20220922095239.2115309-4-schnelle@linux.ibm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220922095239.2115309-1-schnelle@linux.ibm.com> References: <20220922095239.2115309-1-schnelle@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: zVi65bFWdXyqlcOAKOFoh6E3zjfsOLzU X-Proofpoint-GUID: zVi65bFWdXyqlcOAKOFoh6E3zjfsOLzU X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.528,FMLib:17.11.122.1 definitions=2022-09-22_06,2022-09-20_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 bulkscore=0 mlxscore=0 adultscore=0 phishscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 mlxlogscore=999 spamscore=0 priorityscore=1501 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2209130000 definitions=main-2209220063 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" When an s390_domain is freed without previously detaching all devices the corresponding s390_domain_device is leaked. Instead of fixing this leak by freeing the s390_domain_devices in s390_domain_free() do one better and just get rid of s390_domain_device entirely by threading the domain's device list through struct zpci_dev. This also gets rid of a level of indirection during operations but also the allocation of the s390_domain_device during attach thus making it more reliable under memory pressure. Signed-off-by: Niklas Schnelle --- Changes since v1: - No need to iterate the devices list on detach just delete with the zpci_dev handle we have (Jason) - Don't remove list entries on s390_domain_free() instead warn on non-empty list as part of patch 1 arch/s390/include/asm/pci.h | 1 + drivers/iommu/s390-iommu.c | 33 ++++++--------------------------- 2 files changed, 7 insertions(+), 27 deletions(-) diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h index 108e732d7b14..15f8714ca9b7 100644 --- a/arch/s390/include/asm/pci.h +++ b/arch/s390/include/asm/pci.h @@ -117,6 +117,7 @@ struct zpci_bus { struct zpci_dev { struct zpci_bus *zbus; struct list_head entry; /* list of all zpci_devices, needed for hotplug,= etc. */ + struct list_head iommu_list; struct kref kref; struct hotplug_slot hotplug_slot; =20 diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c index 187d2c7ba9ff..e58b5d089418 100644 --- a/drivers/iommu/s390-iommu.c +++ b/drivers/iommu/s390-iommu.c @@ -29,11 +29,6 @@ struct s390_domain { spinlock_t list_lock; }; =20 -struct s390_domain_device { - struct list_head list; - struct zpci_dev *zdev; -}; - static struct s390_domain *to_s390_domain(struct iommu_domain *dom) { return container_of(dom, struct s390_domain, domain); @@ -90,19 +85,11 @@ static void s390_domain_free(struct iommu_domain *domai= n) static int __s390_iommu_detach_device(struct s390_domain *s390_domain, struct zpci_dev *zdev) { - struct s390_domain_device *domain_device, *tmp; unsigned long flags; =20 WARN_ON(zdev->s390_domain !=3D s390_domain); spin_lock_irqsave(&s390_domain->list_lock, flags); - list_for_each_entry_safe(domain_device, tmp, &s390_domain->devices, - list) { - if (domain_device->zdev =3D=3D zdev) { - list_del(&domain_device->list); - kfree(domain_device); - break; - } - } + list_del_init(&zdev->iommu_list); spin_unlock_irqrestore(&s390_domain->list_lock, flags); =20 zpci_unregister_ioat(zdev, 0); @@ -116,7 +103,6 @@ static int s390_iommu_attach_device(struct iommu_domain= *domain, { struct s390_domain *s390_domain =3D to_s390_domain(domain); struct zpci_dev *zdev =3D to_zpci_dev(dev); - struct s390_domain_device *domain_device; struct s390_domain *prev_domain =3D NULL; unsigned long flags; int cc, rc =3D 0; @@ -124,10 +110,6 @@ static int s390_iommu_attach_device(struct iommu_domai= n *domain, if (!zdev) return -ENODEV; =20 - domain_device =3D kzalloc(sizeof(*domain_device), GFP_KERNEL); - if (!domain_device) - return -ENOMEM; - if (zdev->s390_domain) { prev_domain =3D zdev->s390_domain; rc =3D __s390_iommu_detach_device(zdev->s390_domain, zdev); @@ -136,7 +118,7 @@ static int s390_iommu_attach_device(struct iommu_domain= *domain, rc =3D -EIO; } if (rc) - goto out_free; + return rc; =20 zdev->dma_table =3D s390_domain->dma_table; cc =3D zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma, @@ -159,9 +141,8 @@ static int s390_iommu_attach_device(struct iommu_domain= *domain, spin_unlock_irqrestore(&s390_domain->list_lock, flags); goto out_unregister_restore; } - domain_device->zdev =3D zdev; zdev->s390_domain =3D s390_domain; - list_add(&domain_device->list, &s390_domain->devices); + list_add(&zdev->iommu_list, &s390_domain->devices); spin_unlock_irqrestore(&s390_domain->list_lock, flags); =20 return 0; @@ -175,8 +156,6 @@ static int s390_iommu_attach_device(struct iommu_domain= *domain, dev); else zpci_dma_init_device(zdev); -out_free: - kfree(domain_device); =20 return rc; } @@ -228,10 +207,10 @@ static int s390_iommu_update_trans(struct s390_domain= *s390_domain, phys_addr_t pa, dma_addr_t dma_addr, size_t size, int flags) { - struct s390_domain_device *domain_device; phys_addr_t page_addr =3D pa & PAGE_MASK; dma_addr_t start_dma_addr =3D dma_addr; unsigned long irq_flags, nr_pages, i; + struct zpci_dev *zdev; unsigned long *entry; int rc =3D 0; =20 @@ -256,8 +235,8 @@ static int s390_iommu_update_trans(struct s390_domain *= s390_domain, } =20 spin_lock(&s390_domain->list_lock); - list_for_each_entry(domain_device, &s390_domain->devices, list) { - rc =3D zpci_refresh_trans((u64) domain_device->zdev->fh << 32, + list_for_each_entry(zdev, &s390_domain->devices, iommu_list) { + rc =3D zpci_refresh_trans((u64)zdev->fh << 32, start_dma_addr, nr_pages * PAGE_SIZE); if (rc) break; --=20 2.34.1