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=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 C2259C433DF for ; Thu, 2 Jul 2020 21:17:28 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 889252070C for ; Thu, 2 Jul 2020 21:17:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="eaoi8ywr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 889252070C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 5F76589567; Thu, 2 Jul 2020 21:17:28 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id FHo1prndB1MD; Thu, 2 Jul 2020 21:17:27 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id 654BF89565; Thu, 2 Jul 2020 21:17:27 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 568F3C0888; Thu, 2 Jul 2020 21:17:27 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 8B36FC0733 for ; Thu, 2 Jul 2020 21:17:25 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 722C5882A7 for ; Thu, 2 Jul 2020 21:17:25 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id e6TmLYSDlRz7 for ; Thu, 2 Jul 2020 21:17:24 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from us-smtp-delivery-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) by whitealder.osuosl.org (Postfix) with ESMTPS id 0A2F988269 for ; Thu, 2 Jul 2020 21:17:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1593724642; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Nhsfj68WtE/EyvfIEb3mG+EhoeOueYT0YuXe7zxekwU=; b=eaoi8ywrHp92xLhEpR+p3HXGEMFFojm/ONOVmH1hn0gJCsdH9dqzgel8MWDvEZHRwusiB1 cwvhR9apXYiNzJAyWgAS/rR3v05AQ1kcsdK+2BFymOGFpMr2pmm+iqyS/CtX0I0aRxZzYh Os+ltenPJvZqFDtp6IRUgM7PaQ5TLd0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-422-2wOEVkpsNQe8e9GXPpAiNg-1; Thu, 02 Jul 2020 17:17:14 -0400 X-MC-Unique: 2wOEVkpsNQe8e9GXPpAiNg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 402718015F4; Thu, 2 Jul 2020 21:17:12 +0000 (UTC) Received: from x1.home (ovpn-112-156.phx2.redhat.com [10.3.112.156]) by smtp.corp.redhat.com (Postfix) with ESMTP id 294166109F; Thu, 2 Jul 2020 21:17:03 +0000 (UTC) Date: Thu, 2 Jul 2020 15:17:02 -0600 From: Alex Williamson To: Liu Yi L Subject: Re: [PATCH v3 04/14] vfio: Add PASID allocation/free support Message-ID: <20200702151702.1baa65cb@x1.home> In-Reply-To: <1592988927-48009-5-git-send-email-yi.l.liu@intel.com> References: <1592988927-48009-1-git-send-email-yi.l.liu@intel.com> <1592988927-48009-5-git-send-email-yi.l.liu@intel.com> Organization: Red Hat MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Cc: jean-philippe@linaro.org, kevin.tian@intel.com, ashok.raj@intel.com, kvm@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, yi.y.sun@intel.com, hao.wu@intel.com, jun.j.tian@intel.com X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Wed, 24 Jun 2020 01:55:17 -0700 Liu Yi L wrote: > Shared Virtual Addressing (a.k.a Shared Virtual Memory) allows sharing > multiple process virtual address spaces with the device for simplified > programming model. PASID is used to tag an virtual address space in DMA > requests and to identify the related translation structure in IOMMU. When > a PASID-capable device is assigned to a VM, we want the same capability > of using PASID to tag guest process virtual address spaces to achieve > virtual SVA (vSVA). > > PASID management for guest is vendor specific. Some vendors (e.g. Intel > VT-d) requires system-wide managed PASIDs cross all devices, regardless > of whether a device is used by host or assigned to guest. Other vendors > (e.g. ARM SMMU) may allow PASIDs managed per-device thus could be fully > delegated to the guest for assigned devices. > > For system-wide managed PASIDs, this patch introduces a vfio module to > handle explicit PASID alloc/free requests from guest. Allocated PASIDs > are associated to a process (or, mm_struct) in IOASID core. A vfio_mm > object is introduced to track mm_struct. Multiple VFIO containers within > a process share the same vfio_mm object. > > A quota mechanism is provided to prevent malicious user from exhausting > available PASIDs. Currently the quota is a global parameter applied to > all VFIO devices. In the future per-device quota might be supported too. > > Cc: Kevin Tian > CC: Jacob Pan > Cc: Eric Auger > Cc: Jean-Philippe Brucker > Cc: Joerg Roedel > Cc: Lu Baolu > Suggested-by: Alex Williamson > Signed-off-by: Liu Yi L > --- > v1 -> v2: > *) added in v2, split from the pasid alloc/free support of v1 > --- > drivers/vfio/Kconfig | 5 ++ > drivers/vfio/Makefile | 1 + > drivers/vfio/vfio_pasid.c | 151 ++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/vfio.h | 28 +++++++++ > 4 files changed, 185 insertions(+) > create mode 100644 drivers/vfio/vfio_pasid.c > > diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig > index fd17db9..3d8a108 100644 > --- a/drivers/vfio/Kconfig > +++ b/drivers/vfio/Kconfig > @@ -19,6 +19,11 @@ config VFIO_VIRQFD > depends on VFIO && EVENTFD > default n > > +config VFIO_PASID > + tristate > + depends on IOASID && VFIO > + default n > + > menuconfig VFIO > tristate "VFIO Non-Privileged userspace driver framework" > depends on IOMMU_API > diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile > index de67c47..bb836a3 100644 > --- a/drivers/vfio/Makefile > +++ b/drivers/vfio/Makefile > @@ -3,6 +3,7 @@ vfio_virqfd-y := virqfd.o > > obj-$(CONFIG_VFIO) += vfio.o > obj-$(CONFIG_VFIO_VIRQFD) += vfio_virqfd.o > +obj-$(CONFIG_VFIO_PASID) += vfio_pasid.o > obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o > obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o > obj-$(CONFIG_VFIO_SPAPR_EEH) += vfio_spapr_eeh.o > diff --git a/drivers/vfio/vfio_pasid.c b/drivers/vfio/vfio_pasid.c > new file mode 100644 > index 0000000..dd5b6d1 > --- /dev/null > +++ b/drivers/vfio/vfio_pasid.c > @@ -0,0 +1,151 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2020 Intel Corporation. > + * Author: Liu Yi L > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define DRIVER_VERSION "0.1" > +#define DRIVER_AUTHOR "Liu Yi L " > +#define DRIVER_DESC "PASID management for VFIO bus drivers" > + > +#define VFIO_DEFAULT_PASID_QUOTA 1000 > +static int pasid_quota = VFIO_DEFAULT_PASID_QUOTA; > +module_param_named(pasid_quota, pasid_quota, uint, 0444); > +MODULE_PARM_DESC(pasid_quota, > + " Set the quota for max number of PASIDs that an application is allowed to request (default 1000)"); > + > +struct vfio_mm_token { > + unsigned long long val; > +}; > + > +struct vfio_mm { > + struct kref kref; > + struct vfio_mm_token token; > + int ioasid_sid; > + int pasid_quota; > + struct list_head next; > +}; > + > +static struct vfio_pasid { > + struct mutex vfio_mm_lock; > + struct list_head vfio_mm_list; > +} vfio_pasid; > + > +/* called with vfio.vfio_mm_lock held */ > +static void vfio_mm_release(struct kref *kref) > +{ > + struct vfio_mm *vmm = container_of(kref, struct vfio_mm, kref); > + > + list_del(&vmm->next); > + mutex_unlock(&vfio_pasid.vfio_mm_lock); > + ioasid_free_set(vmm->ioasid_sid, true); > + kfree(vmm); > +} > + > +void vfio_mm_put(struct vfio_mm *vmm) > +{ > + kref_put_mutex(&vmm->kref, vfio_mm_release, &vfio_pasid.vfio_mm_lock); > +} > + > +static void vfio_mm_get(struct vfio_mm *vmm) > +{ > + kref_get(&vmm->kref); > +} > + > +struct vfio_mm *vfio_mm_get_from_task(struct task_struct *task) > +{ > + struct mm_struct *mm = get_task_mm(task); > + struct vfio_mm *vmm; > + unsigned long long val = (unsigned long long) mm; > + int ret; > + > + mutex_lock(&vfio_pasid.vfio_mm_lock); > + /* Search existing vfio_mm with current mm pointer */ > + list_for_each_entry(vmm, &vfio_pasid.vfio_mm_list, next) { > + if (vmm->token.val == val) { > + vfio_mm_get(vmm); > + goto out; > + } > + } > + > + vmm = kzalloc(sizeof(*vmm), GFP_KERNEL); > + if (!vmm) > + return ERR_PTR(-ENOMEM); lock leaked, mm leaked. > + > + /* > + * IOASID core provides a 'IOASID set' concept to track all > + * PASIDs associated with a token. Here we use mm_struct as > + * the token and create a IOASID set per mm_struct. All the > + * containers of the process share the same IOASID set. > + */ > + ret = ioasid_alloc_set((struct ioasid_set *) mm, pasid_quota, > + &vmm->ioasid_sid); > + if (ret) { > + kfree(vmm); > + return ERR_PTR(ret); lock leaked, mm leaked. > + } > + > + kref_init(&vmm->kref); > + vmm->token.val = (unsigned long long) mm; We already have it in @val. > + vmm->pasid_quota = pasid_quota; This field on the structure and this assignment seems to serve no purpose. Thanks, Alex > + > + list_add(&vmm->next, &vfio_pasid.vfio_mm_list); > +out: > + mutex_unlock(&vfio_pasid.vfio_mm_lock); > + mmput(mm); > + return vmm; > +} > + > +int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max) > +{ > + ioasid_t pasid; > + > + pasid = ioasid_alloc(vmm->ioasid_sid, min, max, NULL); > + > + return (pasid == INVALID_IOASID) ? -ENOSPC : pasid; > +} > + > +void vfio_pasid_free_range(struct vfio_mm *vmm, > + ioasid_t min, ioasid_t max) > +{ > + ioasid_t pasid = min; > + > + if (min > max) > + return; > + > + /* > + * IOASID core will notify PASID users (e.g. IOMMU driver) to > + * teardown necessary structures depending on the to-be-freed > + * PASID. > + */ > + for (; pasid <= max; pasid++) > + ioasid_free(pasid); > +} > + > +static int __init vfio_pasid_init(void) > +{ > + mutex_init(&vfio_pasid.vfio_mm_lock); > + INIT_LIST_HEAD(&vfio_pasid.vfio_mm_list); > + return 0; > +} > + > +static void __exit vfio_pasid_exit(void) > +{ > + WARN_ON(!list_empty(&vfio_pasid.vfio_mm_list)); > +} > + > +module_init(vfio_pasid_init); > +module_exit(vfio_pasid_exit); > + > +MODULE_VERSION(DRIVER_VERSION); > +MODULE_LICENSE("GPL v2"); > +MODULE_AUTHOR(DRIVER_AUTHOR); > +MODULE_DESCRIPTION(DRIVER_DESC); > diff --git a/include/linux/vfio.h b/include/linux/vfio.h > index 38d3c6a..74e077d 100644 > --- a/include/linux/vfio.h > +++ b/include/linux/vfio.h > @@ -97,6 +97,34 @@ extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops); > extern void vfio_unregister_iommu_driver( > const struct vfio_iommu_driver_ops *ops); > > +struct vfio_mm; > +#if IS_ENABLED(CONFIG_VFIO_PASID) > +extern struct vfio_mm *vfio_mm_get_from_task(struct task_struct *task); > +extern void vfio_mm_put(struct vfio_mm *vmm); > +extern int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max); > +extern void vfio_pasid_free_range(struct vfio_mm *vmm, > + ioasid_t min, ioasid_t max); > +#else > +static inline struct vfio_mm *vfio_mm_get_from_task(struct task_struct *task) > +{ > + return NULL; > +} > + > +static inline void vfio_mm_put(struct vfio_mm *vmm) > +{ > +} > + > +static inline int vfio_pasid_alloc(struct vfio_mm *vmm, int min, int max) > +{ > + return -ENOTTY; > +} > + > +static inline void vfio_pasid_free_range(struct vfio_mm *vmm, > + ioasid_t min, ioasid_t max) > +{ > +} > +#endif /* CONFIG_VFIO_PASID */ > + > /* > * External user API > */ _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu