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=-8.1 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,USER_AGENT_SANE_1 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 C0536C43331 for ; Tue, 12 Nov 2019 09:55:06 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 89C00206BA for ; Tue, 12 Nov 2019 09:55:06 +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="XpPneiWR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 89C00206BA 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 mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 55A16156D; Tue, 12 Nov 2019 09:55:06 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id D7F271568 for ; Tue, 12 Nov 2019 09:55:05 +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 [207.211.31.81]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 066434C3 for ; Tue, 12 Nov 2019 09:55:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1573552503; 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=m+FxLvEY0C/giy8/h+xtIwqhQ621a6X8ZoITux0zyQI=; b=XpPneiWRg95ZtH7qw3DD6o7MAv5comKy16cAtxa6iW4Xz+QrMSyEQbXt0LlKijngH9Liww uXwaRIyBuO+h2qzZOE/sJzzM1PePuJ9gWUy36w8L5Q1Uynyni1luvq6oe/LBLUMFAQv1b4 sBgXicX7hog/0neE5w6StnDorFLs0lg= 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-39-uiQ0zLRMOBaPn5-IwFwgYg-1; Tue, 12 Nov 2019 04:55:00 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 735E91800D7A; Tue, 12 Nov 2019 09:54:58 +0000 (UTC) Received: from [10.36.116.54] (ovpn-116-54.ams2.redhat.com [10.36.116.54]) by smtp.corp.redhat.com (Postfix) with ESMTPS id EB5785C1C3; Tue, 12 Nov 2019 09:54:50 +0000 (UTC) Subject: Re: [PATCH v7 04/11] iommu/vt-d: Replace Intel specific PASID allocator with IOASID To: Jacob Pan References: <1571946904-86776-1-git-send-email-jacob.jun.pan@linux.intel.com> <1571946904-86776-5-git-send-email-jacob.jun.pan@linux.intel.com> <20191108145506.6bcb6f9e@jacob-builder> From: Auger Eric Message-ID: Date: Tue, 12 Nov 2019 10:54:48 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20191108145506.6bcb6f9e@jacob-builder> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-MC-Unique: uiQ0zLRMOBaPn5-IwFwgYg-1 X-Mimecast-Spam-Score: 0 Cc: "Tian, Kevin" , Raj Ashok , David Woodhouse , iommu@lists.linux-foundation.org, LKML , Alex Williamson , Jean-Philippe Brucker , Jonathan Cameron X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 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 Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org Hi Jacob, On 11/8/19 11:55 PM, Jacob Pan wrote: > On Fri, 8 Nov 2019 12:30:31 +0100 > Auger Eric wrote: > >> Hi Jacob, >> >> On 10/24/19 9:54 PM, Jacob Pan wrote: >>> Make use of generic IOASID code to manage PASID allocation, >>> free, and lookup. Replace Intel specific code. >>> >>> Signed-off-by: Jacob Pan >>> --- >>> drivers/iommu/intel-iommu.c | 12 ++++++------ >>> drivers/iommu/intel-pasid.c | 36 >>> ------------------------------------ drivers/iommu/intel-svm.c | >>> 39 +++++++++++++++++++++++---------------- 3 files changed, 29 >>> insertions(+), 58 deletions(-) >>> >>> diff --git a/drivers/iommu/intel-iommu.c >>> b/drivers/iommu/intel-iommu.c index ced1d89ef977..2ea09b988a23 >>> 100644 --- a/drivers/iommu/intel-iommu.c >>> +++ b/drivers/iommu/intel-iommu.c >>> @@ -5311,7 +5311,7 @@ static void auxiliary_unlink_device(struct >>> dmar_domain *domain, domain->auxd_refcnt--; >>> >>> if (!domain->auxd_refcnt && domain->default_pasid > 0) >>> - intel_pasid_free_id(domain->default_pasid); >>> + ioasid_free(domain->default_pasid); >>> } >>> >>> static int aux_domain_add_dev(struct dmar_domain *domain, >>> @@ -5329,10 +5329,10 @@ static int aux_domain_add_dev(struct >>> dmar_domain *domain, if (domain->default_pasid <= 0) { >>> int pasid; >>> >>> - pasid = intel_pasid_alloc_id(domain, PASID_MIN, >>> - >>> pci_max_pasids(to_pci_dev(dev)), >>> - GFP_KERNEL); >>> - if (pasid <= 0) { >>> + /* No private data needed for the default pasid */ >>> + pasid = ioasid_alloc(NULL, PASID_MIN, >>> pci_max_pasids(to_pci_dev(dev)) - 1, >>> + NULL); >>> + if (pasid == INVALID_IOASID) { >>> pr_err("Can't allocate default pasid\n"); >>> return -ENODEV; >>> } >>> @@ -5368,7 +5368,7 @@ static int aux_domain_add_dev(struct >>> dmar_domain *domain, spin_unlock(&iommu->lock); >>> spin_unlock_irqrestore(&device_domain_lock, flags); >>> if (!domain->auxd_refcnt && domain->default_pasid > 0) >>> - intel_pasid_free_id(domain->default_pasid); >>> + ioasid_free(domain->default_pasid); >>> >>> return ret; >>> } >>> diff --git a/drivers/iommu/intel-pasid.c >>> b/drivers/iommu/intel-pasid.c index d81e857d2b25..e79d680fe300 >>> 100644 --- a/drivers/iommu/intel-pasid.c >>> +++ b/drivers/iommu/intel-pasid.c >>> @@ -26,42 +26,6 @@ >>> */ >>> static DEFINE_SPINLOCK(pasid_lock); >>> u32 intel_pasid_max_id = PASID_MAX; >>> -static DEFINE_IDR(pasid_idr); >>> - >>> -int intel_pasid_alloc_id(void *ptr, int start, int end, gfp_t gfp) >>> -{ >>> - int ret, min, max; >>> - >>> - min = max_t(int, start, PASID_MIN); >>> - max = min_t(int, end, intel_pasid_max_id); >>> - >>> - WARN_ON(in_interrupt()); >>> - idr_preload(gfp); >>> - spin_lock(&pasid_lock); >>> - ret = idr_alloc(&pasid_idr, ptr, min, max, GFP_ATOMIC); >>> - spin_unlock(&pasid_lock); >>> - idr_preload_end(); >>> - >>> - return ret; >>> -} >>> - >>> -void intel_pasid_free_id(int pasid) >>> -{ >>> - spin_lock(&pasid_lock); >>> - idr_remove(&pasid_idr, pasid); >>> - spin_unlock(&pasid_lock); >>> -} >>> - >>> -void *intel_pasid_lookup_id(int pasid) >>> -{ >>> - void *p; >>> - >>> - spin_lock(&pasid_lock); >>> - p = idr_find(&pasid_idr, pasid); >>> - spin_unlock(&pasid_lock); >>> - >>> - return p; >>> -} >>> >>> int vcmd_alloc_pasid(struct intel_iommu *iommu, unsigned int >>> *pasid) { >>> diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c >>> index 9b159132405d..a9a7f85a09bc 100644 >>> --- a/drivers/iommu/intel-svm.c >>> +++ b/drivers/iommu/intel-svm.c >>> @@ -17,6 +17,7 @@ >>> #include >>> #include >>> #include >>> +#include >>> #include >>> >>> #include "intel-pasid.h" >>> @@ -318,16 +319,15 @@ int intel_svm_bind_mm(struct device *dev, int >>> *pasid, int flags, struct svm_dev_ if (pasid_max > >>> intel_pasid_max_id) pasid_max = intel_pasid_max_id; >>> >>> - /* Do not use PASID 0 in caching mode (virtualised >>> IOMMU) */ >>> - ret = intel_pasid_alloc_id(svm, >>> - !!cap_caching_mode(iommu->cap), >>> - pasid_max - 1, >>> GFP_KERNEL); >>> - if (ret < 0) { >>> + /* Do not use PASID 0, reserved for RID to PASID */ >>> + svm->pasid = ioasid_alloc(NULL, PASID_MIN, >>> + pasid_max - 1, svm); >> pasid_max -1 is inclusive. whereas max param in intel_pasid_alloc_id() >> is exclusive right? If you fixed an issue, you can mention it in the >> commit message. > yes, i should mention that. intel_pasid_alloc_id() uses IDR which is > end exclusive. ioasid uses xarray, which is inclusive. >>> + if (svm->pasid == INVALID_IOASID) { >>> kfree(svm);> >>> kfree(sdev); >>> + ret = ENOSPC; >> -ENOSPC. >> Nit: in 2/11 vcmd_alloc_pasid returned -ENOMEM > yes, it should be -ENOSPC as well. > >>> goto out; >>> } >>> - svm->pasid = ret; >>> svm->notifier.ops = &intel_mmuops; >>> svm->mm = mm; >>> svm->flags = flags; >>> @@ -337,7 +337,7 @@ int intel_svm_bind_mm(struct device *dev, int >>> *pasid, int flags, struct svm_dev_ if (mm) { >>> ret = >>> mmu_notifier_register(&svm->notifier, mm); if (ret) { >>> - intel_pasid_free_id(svm->pasid); >>> + ioasid_free(svm->pasid); >>> kfree(svm); >>> kfree(sdev); >>> goto out; >>> @@ -353,7 +353,7 @@ int intel_svm_bind_mm(struct device *dev, int >>> *pasid, int flags, struct svm_dev_ if (ret) { >>> if (mm) >>> mmu_notifier_unregister(&svm->notifier, >>> mm); >>> - intel_pasid_free_id(svm->pasid); >>> + ioasid_free(svm->pasid); >>> kfree(svm); >>> kfree(sdev); >>> goto out; >>> @@ -401,7 +401,12 @@ int intel_svm_unbind_mm(struct device *dev, >>> int pasid) if (!iommu) >>> goto out; >>> >>> - svm = intel_pasid_lookup_id(pasid); >>> + svm = ioasid_find(NULL, pasid, NULL); >>> + if (IS_ERR(svm)) { >>> + ret = PTR_ERR(svm); >>> + goto out; >>> + } >>> + >>> if (!svm) >>> goto out; >>> >>> @@ -423,7 +428,9 @@ int intel_svm_unbind_mm(struct device *dev, int >>> pasid) kfree_rcu(sdev, rcu); >>> >>> if (list_empty(&svm->devs)) { >>> - >>> intel_pasid_free_id(svm->pasid); >>> + /* Clear private data so >>> that free pass check */> + >>> ioasid_set_data(svm->pasid, NULL); >> I don't get the above comment. Why is it needed? > Having private data associated with an IOASID is an indicator that this > IOASID is busy. So we have to clear it to signal it is free. > Actually, I am planning to introduce a refcount per IOASID since there > will be multiple users of IOASID, e.g. IOMMU driver and KVM. When > refcount == 0, we can free. Ah OK I missed that. This is a specificity of the intel custom PASID allocator, ie intel_ioasid_free and not a generic behavior. Thanks Eric > >>> + ioasid_free(svm->pasid); >>> if (svm->mm) >>> mmu_notifier_unregister(&svm->notifier, >>> svm->mm); >>> @@ -458,10 +465,11 @@ int intel_svm_is_pasid_valid(struct device >>> *dev, int pasid) if (!iommu) >>> goto out; >>> >>> - svm = intel_pasid_lookup_id(pasid); >>> - if (!svm) >>> + svm = ioasid_find(NULL, pasid, NULL); >>> + if (IS_ERR(svm)) { >>> + ret = PTR_ERR(svm); >>> goto out; >>> - >>> + } >>> /* init_mm is used in this case */ >>> if (!svm->mm) >>> ret = 1; >>> @@ -568,13 +576,12 @@ static irqreturn_t prq_event_thread(int irq, >>> void *d) >>> if (!svm || svm->pasid != req->pasid) { >>> rcu_read_lock(); >>> - svm = intel_pasid_lookup_id(req->pasid); >>> + svm = ioasid_find(NULL, req->pasid, NULL); >>> /* It *can't* go away, because the driver >>> is not permitted >>> * to unbind the mm while any page faults >>> are outstanding. >>> * So we only need RCU to protect the >>> internal idr code. */ rcu_read_unlock(); >>> - >>> - if (!svm) { >>> + if (IS_ERR(svm) || !svm) { >>> pr_err("%s: Page request for >>> invalid PASID %d: %08llx %08llx\n", iommu->name, req->pasid, >>> ((unsigned long long *)req)[0], ((unsigned long long *)req)[1]); >>> >> Thanks >> >> Eric >> > > [Jacob Pan] > _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu