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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 0DE41C49EA6 for ; Thu, 24 Jun 2021 04:28:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA727613CF for ; Thu, 24 Jun 2021 04:28:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229776AbhFXEa6 (ORCPT ); Thu, 24 Jun 2021 00:30:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229878AbhFXEay (ORCPT ); Thu, 24 Jun 2021 00:30:54 -0400 Received: from mail-qk1-x72b.google.com (mail-qk1-x72b.google.com [IPv6:2607:f8b0:4864:20::72b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1079CC06175F for ; Wed, 23 Jun 2021 21:28:34 -0700 (PDT) Received: by mail-qk1-x72b.google.com with SMTP id bl4so11135782qkb.8 for ; Wed, 23 Jun 2021 21:28:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Vf6iRayWkpLOoYUf7pNtG+CaRTyVw0JAqulSitMDQO0=; b=XhlMv+xUBROxE3lM6Rw1CgXO1kddD8cgUoOHPx8CrrP4EyoU4DEd7SG1RL9I+0DYan boJUZwUYrjArp3SWtAGk9E+FeS6qz4WFyjdbkPcDaZ6Ojv9o8/zJPPYdzKO3qy5vBtEQ HXmGW25TeHi/8kTi8dJmCqS/q5sIDUcuof6X0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Vf6iRayWkpLOoYUf7pNtG+CaRTyVw0JAqulSitMDQO0=; b=LoNOpSVjFxtJF3rj3/7gV+P+UTMvHNH6c5n/Tw7+uDsaeaPvsXU4yiOvXCDjWUeh+S yV22BOE9K7CSSFECKrFYTtV9QskJ//cs537On3jVcKIm8s4lonJXHwgD9gX71INIV27R 2SeliWQFmLqMaOrAxFzzjDlI8ugMSQP7p/jUcb8uy5zOSXlg9dr0LPeM8ouhhJyTyu4E FGHPVg4bwQJh0zrYvYQoYBCqCoKqWXKlqSqoE8euTPNNlZZ/nOtiidV8Ym061eveJifT GOWt2O1oMRrX/EVr/Cey55XJP2JLBGVp8WriCWyigO4IRp8eRdvYWDyA3GY5Xb/Fty5t JINQ== X-Gm-Message-State: AOAM532t0pOgnPYNDQNJ/JYd1uh94nhw1w6xmqx/ZDs+2F9B+bJggRmf tJhrIAImJw5bEERrvvrdvG8k7p2w3dFCv4s5QdPTHg== X-Google-Smtp-Source: ABdhPJzN6yIAnrutP4mXY4YUqxFUME7cFcfwCCdv9KLoP/1Ux65U8D0qn4SKiYpFY+s6pSHfO29nSf+YvOucHrB1PFc= X-Received: by 2002:a05:620a:1a87:: with SMTP id bl7mr3690332qkb.232.1624508913860; Wed, 23 Jun 2021 21:28:33 -0700 (PDT) MIME-Version: 1.0 References: <20210624035749.4054934-1-stevensd@google.com> <20210624035749.4054934-7-stevensd@google.com> In-Reply-To: <20210624035749.4054934-7-stevensd@google.com> From: David Stevens Date: Thu, 24 Jun 2021 13:28:23 +0900 Message-ID: Subject: Re: [PATCH 6/6] drm/i915/gvt: use gfn_to_pfn's page instead of pfn To: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Paolo Bonzini , Zhenyu Wang , Zhi Wang Cc: James Morse , Alexandru Elisei , Suzuki K Poulose , Will Deacon , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, open list , linux-mips@vger.kernel.org, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, ML dri-devel , David Stevens Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Please ignore this last patch. It was put together as an afterthought and wasn't properly tested. -David On Thu, Jun 24, 2021 at 12:59 PM David Stevens wrote: > > Return struct page instead of pfn from gfn_to_mfn. This function is only > used to determine if the page is a transparent hugepage, to enable 2MB > huge gtt shadowing. Returning the page directly avoids the risk of > calling pfn_to_page on a VM_IO|VM_PFNMAP pfn. > > This change also properly releases the reference on the page returned by > gfn_to_pfn. > > Signed-off-by: David Stevens > --- > drivers/gpu/drm/i915/gvt/gtt.c | 12 ++++++++---- > drivers/gpu/drm/i915/gvt/hypercall.h | 3 ++- > drivers/gpu/drm/i915/gvt/kvmgt.c | 12 ++++-------- > drivers/gpu/drm/i915/gvt/mpt.h | 8 ++++---- > 4 files changed, 18 insertions(+), 17 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c > index 9478c132d7b6..b2951c560582 100644 > --- a/drivers/gpu/drm/i915/gvt/gtt.c > +++ b/drivers/gpu/drm/i915/gvt/gtt.c > @@ -1160,16 +1160,20 @@ static int is_2MB_gtt_possible(struct intel_vgpu *vgpu, > struct intel_gvt_gtt_entry *entry) > { > struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops; > - unsigned long pfn; > + struct page *page; > + bool is_trans_huge; > > if (!HAS_PAGE_SIZES(vgpu->gvt->gt->i915, I915_GTT_PAGE_SIZE_2M)) > return 0; > > - pfn = intel_gvt_hypervisor_gfn_to_mfn(vgpu, ops->get_pfn(entry)); > - if (pfn == INTEL_GVT_INVALID_ADDR) > + page = intel_gvt_hypervisor_gfn_to_mfn_page(vgpu, ops->get_pfn(entry)); > + if (!page) > return -EINVAL; > > - return PageTransHuge(pfn_to_page(pfn)); > + is_trans_huge = PageTransHuge(page); > + put_page(page); > + > + return is_trans_huge; > } > > static int split_2MB_gtt_entry(struct intel_vgpu *vgpu, > diff --git a/drivers/gpu/drm/i915/gvt/hypercall.h b/drivers/gpu/drm/i915/gvt/hypercall.h > index b79da5124f83..017190ff52d5 100644 > --- a/drivers/gpu/drm/i915/gvt/hypercall.h > +++ b/drivers/gpu/drm/i915/gvt/hypercall.h > @@ -60,7 +60,8 @@ struct intel_gvt_mpt { > unsigned long len); > int (*write_gpa)(unsigned long handle, unsigned long gpa, void *buf, > unsigned long len); > - unsigned long (*gfn_to_mfn)(unsigned long handle, unsigned long gfn); > + struct page *(*gfn_to_mfn_page)(unsigned long handle, > + unsigned long gfn); > > int (*dma_map_guest_page)(unsigned long handle, unsigned long gfn, > unsigned long size, dma_addr_t *dma_addr); > diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c > index b829ff67e3d9..1e97ae813ed0 100644 > --- a/drivers/gpu/drm/i915/gvt/kvmgt.c > +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c > @@ -1928,21 +1928,17 @@ static int kvmgt_inject_msi(unsigned long handle, u32 addr, u16 data) > return -EFAULT; > } > > -static unsigned long kvmgt_gfn_to_pfn(unsigned long handle, unsigned long gfn) > +static struct page *kvmgt_gfn_to_page(unsigned long handle, unsigned long gfn) > { > struct kvmgt_guest_info *info; > kvm_pfn_t pfn; > > if (!handle_valid(handle)) > - return INTEL_GVT_INVALID_ADDR; > + return NULL; > > info = (struct kvmgt_guest_info *)handle; > > - pfn = kvm_pfn_page_unwrap(gfn_to_pfn(info->kvm, gfn)); > - if (is_error_noslot_pfn(pfn)) > - return INTEL_GVT_INVALID_ADDR; > - > - return pfn; > + return gfn_to_pfn(info->kvm, gfn).page; > } > > static int kvmgt_dma_map_guest_page(unsigned long handle, unsigned long gfn, > @@ -2112,7 +2108,7 @@ static const struct intel_gvt_mpt kvmgt_mpt = { > .disable_page_track = kvmgt_page_track_remove, > .read_gpa = kvmgt_read_gpa, > .write_gpa = kvmgt_write_gpa, > - .gfn_to_mfn = kvmgt_gfn_to_pfn, > + .gfn_to_mfn_page = kvmgt_gfn_to_page, > .dma_map_guest_page = kvmgt_dma_map_guest_page, > .dma_unmap_guest_page = kvmgt_dma_unmap_guest_page, > .dma_pin_guest_page = kvmgt_dma_pin_guest_page, > diff --git a/drivers/gpu/drm/i915/gvt/mpt.h b/drivers/gpu/drm/i915/gvt/mpt.h > index 550a456e936f..9169b83cf0f6 100644 > --- a/drivers/gpu/drm/i915/gvt/mpt.h > +++ b/drivers/gpu/drm/i915/gvt/mpt.h > @@ -214,17 +214,17 @@ static inline int intel_gvt_hypervisor_write_gpa(struct intel_vgpu *vgpu, > } > > /** > - * intel_gvt_hypervisor_gfn_to_mfn - translate a GFN to MFN > + * intel_gvt_hypervisor_gfn_to_mfn_page - translate a GFN to MFN page > * @vgpu: a vGPU > * @gpfn: guest pfn > * > * Returns: > - * MFN on success, INTEL_GVT_INVALID_ADDR if failed. > + * struct page* on success, NULL if failed. > */ > -static inline unsigned long intel_gvt_hypervisor_gfn_to_mfn( > +static inline unsigned long intel_gvt_hypervisor_gfn_to_mfn_page( > struct intel_vgpu *vgpu, unsigned long gfn) > { > - return intel_gvt_host.mpt->gfn_to_mfn(vgpu->handle, gfn); > + return intel_gvt_host.mpt->gfn_to_mfn_page(vgpu->handle, gfn); > } > > /** > -- > 2.32.0.93.g670b81a890-goog >