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=-8.2 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 08830C67839 for ; Fri, 14 Dec 2018 08:35:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A66BA208E7 for ; Fri, 14 Dec 2018 08:35:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="HRJNZk6M" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A66BA208E7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727769AbeLNIfZ (ORCPT ); Fri, 14 Dec 2018 03:35:25 -0500 Received: from mail-ed1-f65.google.com ([209.85.208.65]:35913 "EHLO mail-ed1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726998AbeLNIfZ (ORCPT ); Fri, 14 Dec 2018 03:35:25 -0500 Received: by mail-ed1-f65.google.com with SMTP id f23so4288565edb.3 for ; Fri, 14 Dec 2018 00:35:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=sender:date:from:to:cc:subject:message-id:mail-followup-to :references:mime-version:content-disposition:in-reply-to:user-agent; bh=70dVirz4fnBbVianUK2jDuCnZkgXC35g87hwr8o0saU=; b=HRJNZk6MutYi1mFHPwQp9kpRAsNeTIo3bQ+qM+OcbEfn/ewtayo4d9y4XDTQ+/11tm dEMYMGhkJKigqhR8PsHaf/h4nFjzFAhUpNAkeAAwbx6lmUgxpj08mWmsbH+hyM9u1DsT LQiPJg1Vgn89rD3wkAwBlTr7RS2zEJQbEEM/k= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :mail-followup-to:references:mime-version:content-disposition :in-reply-to:user-agent; bh=70dVirz4fnBbVianUK2jDuCnZkgXC35g87hwr8o0saU=; b=MBXHxrCIscaALMBs4GB9UjcRTwqgok0jFI9iV948AUc3+48//g+95qjb71mH/DiNNe X8mdngwdzVGYT34SjNcQ9A4Rx/x4aHzRTWTVLz1pwBHQd41QyCDrLSiCCWn1wKEOU5Ex GEzoZc+tslF03UOaN0T3Y02zWLECM3yCYfCHTbEu3G56q2FVWoj7eIo3fCFV9nLWKmgR hXEVkMr3lTxHWa7h9N4dkoLyplJ7BTFuA0tGg5a73w5X60UWaSUqdEysB2bxSVEOO5lL m7QKE2MupJEPSEBKsc8Q092iX2XBdb/tPw0BhGI0C1IIdDHA+nYWUESict/RlGxjthkU qZUw== X-Gm-Message-State: AA+aEWbNQzqL0AmFvUMoLiIjT0HkXJwWD61Kg5gdyaGlDd+YQKzua7tC eillTVruHPojwIPdS3itBJBRkA== X-Google-Smtp-Source: AFSGD/VLxxPKxlCj9M8MP5ypWnxHmE6jVHKKBBFhwkLbPcnlADHGhSQcfw2pCFSKlaVOrFJTGiutdw== X-Received: by 2002:aa7:c0d0:: with SMTP id j16mr2164856edp.173.1544776522781; Fri, 14 Dec 2018 00:35:22 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:569e:0:3106:d637:d723:e855]) by smtp.gmail.com with ESMTPSA id t26sm1308279eda.22.2018.12.14.00.35.21 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 14 Dec 2018 00:35:21 -0800 (PST) Date: Fri, 14 Dec 2018 09:35:19 +0100 From: Daniel Vetter To: Oleksandr Andrushchenko Cc: Daniel Vetter , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, jgross@suse.com, boris.ostrovsky@oracle.com, Oleksandr Andrushchenko Subject: Re: [PATCH] drm/xen-front: Make shmem backed display buffer coherent Message-ID: <20181214083519.GI21184@phenom.ffwll.local> Mail-Followup-To: Oleksandr Andrushchenko , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, jgross@suse.com, boris.ostrovsky@oracle.com, Oleksandr Andrushchenko References: <20181127103252.20994-1-andr2000@gmail.com> <20181213154845.GF21184@phenom.ffwll.local> <57b468f5-cf7a-0dcd-fef8-fd399025fb45@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <57b468f5-cf7a-0dcd-fef8-fd399025fb45@gmail.com> X-Operating-System: Linux phenom 4.18.0-2-amd64 User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 14, 2018 at 09:09:45AM +0200, Oleksandr Andrushchenko wrote: > On 12/13/18 5:48 PM, Daniel Vetter wrote: > > On Thu, Dec 13, 2018 at 12:17:54PM +0200, Oleksandr Andrushchenko wrote: > > > Daniel, could you please comment? > > Cross-revieweing someone else's stuff would scale better, > fair enough > > I don't think > > I'll get around to anything before next year. > > I put you on CC explicitly because you had comments on other patch [1] > > and this one tries to solve the issue raised (I tried to figure out > > at [2] if this is the way to go, but it seems I have no alternative here). > > While at it [3] (I hope) addresses your comments and the series just > > needs your single ack/nack to get in: all the rest ack/r-b are already > > there. Do you mind looking at it? As mentioned, much better if you aim for more per review with others, not just me. And all that dma coherency stuff isn't something a really understand all that well (I just know we have lots of pain). For options maybe work together with Gerd Hoffman or Noralf Tronnes, I think either has some patches pending that also need some review. -Daniel > > > -Daniel > > Thank you very much for your time, > > Oleksandr > > > > Thank you > > > > > > On 11/27/18 12:32 PM, Oleksandr Andrushchenko wrote: > > > > From: Oleksandr Andrushchenko > > > > > > > > When GEM backing storage is allocated with drm_gem_get_pages > > > > the backing pages may be cached, thus making it possible that > > > > the backend sees only partial content of the buffer which may > > > > lead to screen artifacts. Make sure that the frontend's > > > > memory is coherent and the backend always sees correct display > > > > buffer content. > > > > > > > > Fixes: c575b7eeb89f ("drm/xen-front: Add support for Xen PV display frontend") > > > > > > > > Signed-off-by: Oleksandr Andrushchenko > > > > --- > > > > drivers/gpu/drm/xen/xen_drm_front_gem.c | 62 +++++++++++++++++++------ > > > > 1 file changed, 48 insertions(+), 14 deletions(-) > > > > > > > > diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c > > > > index 47ff019d3aef..c592735e49d2 100644 > > > > --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c > > > > +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c > > > > @@ -33,8 +33,11 @@ struct xen_gem_object { > > > > /* set for buffers allocated by the backend */ > > > > bool be_alloc; > > > > - /* this is for imported PRIME buffer */ > > > > - struct sg_table *sgt_imported; > > > > + /* > > > > + * this is for imported PRIME buffer or the one allocated via > > > > + * drm_gem_get_pages. > > > > + */ > > > > + struct sg_table *sgt; > > > > }; > > > > static inline struct xen_gem_object * > > > > @@ -77,10 +80,21 @@ static struct xen_gem_object *gem_create_obj(struct drm_device *dev, > > > > return xen_obj; > > > > } > > > > +struct sg_table *xen_drm_front_gem_get_sg_table(struct drm_gem_object *gem_obj) > > > > +{ > > > > + struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj); > > > > + > > > > + if (!xen_obj->pages) > > > > + return ERR_PTR(-ENOMEM); > > > > + > > > > + return drm_prime_pages_to_sg(xen_obj->pages, xen_obj->num_pages); > > > > +} > > > > + > > > > static struct xen_gem_object *gem_create(struct drm_device *dev, size_t size) > > > > { > > > > struct xen_drm_front_drm_info *drm_info = dev->dev_private; > > > > struct xen_gem_object *xen_obj; > > > > + struct address_space *mapping; > > > > int ret; > > > > size = round_up(size, PAGE_SIZE); > > > > @@ -113,10 +127,14 @@ static struct xen_gem_object *gem_create(struct drm_device *dev, size_t size) > > > > xen_obj->be_alloc = true; > > > > return xen_obj; > > > > } > > > > + > > > > /* > > > > * need to allocate backing pages now, so we can share those > > > > * with the backend > > > > */ > > > > + mapping = xen_obj->base.filp->f_mapping; > > > > + mapping_set_gfp_mask(mapping, GFP_USER | __GFP_DMA32); > > > > + > > > > xen_obj->num_pages = DIV_ROUND_UP(size, PAGE_SIZE); > > > > xen_obj->pages = drm_gem_get_pages(&xen_obj->base); > > > > if (IS_ERR_OR_NULL(xen_obj->pages)) { > > > > @@ -125,8 +143,27 @@ static struct xen_gem_object *gem_create(struct drm_device *dev, size_t size) > > > > goto fail; > > > > } > > > > + xen_obj->sgt = xen_drm_front_gem_get_sg_table(&xen_obj->base); > > > > + if (IS_ERR_OR_NULL(xen_obj->sgt)){ > > > > + ret = PTR_ERR(xen_obj->sgt); > > > > + xen_obj->sgt = NULL; > > > > + goto fail_put_pages; > > > > + } > > > > + > > > > + if (!dma_map_sg(dev->dev, xen_obj->sgt->sgl, xen_obj->sgt->nents, > > > > + DMA_BIDIRECTIONAL)) { > > > > + ret = -EFAULT; > > > > + goto fail_free_sgt; > > > > + } > > > > + > > > > return xen_obj; > > > > +fail_free_sgt: > > > > + sg_free_table(xen_obj->sgt); > > > > + xen_obj->sgt = NULL; > > > > +fail_put_pages: > > > > + drm_gem_put_pages(&xen_obj->base, xen_obj->pages, true, false); > > > > + xen_obj->pages = NULL; > > > > fail: > > > > DRM_ERROR("Failed to allocate buffer with size %zu\n", size); > > > > return ERR_PTR(ret); > > > > @@ -149,7 +186,7 @@ void xen_drm_front_gem_free_object_unlocked(struct drm_gem_object *gem_obj) > > > > struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj); > > > > if (xen_obj->base.import_attach) { > > > > - drm_prime_gem_destroy(&xen_obj->base, xen_obj->sgt_imported); > > > > + drm_prime_gem_destroy(&xen_obj->base, xen_obj->sgt); > > > > gem_free_pages_array(xen_obj); > > > > } else { > > > > if (xen_obj->pages) { > > > > @@ -158,6 +195,13 @@ void xen_drm_front_gem_free_object_unlocked(struct drm_gem_object *gem_obj) > > > > xen_obj->pages); > > > > gem_free_pages_array(xen_obj); > > > > } else { > > > > + if (xen_obj->sgt) { > > > > + dma_unmap_sg(xen_obj->base.dev->dev, > > > > + xen_obj->sgt->sgl, > > > > + xen_obj->sgt->nents, > > > > + DMA_BIDIRECTIONAL); > > > > + sg_free_table(xen_obj->sgt); > > > > + } > > > > drm_gem_put_pages(&xen_obj->base, > > > > xen_obj->pages, true, false); > > > > } > > > > @@ -174,16 +218,6 @@ struct page **xen_drm_front_gem_get_pages(struct drm_gem_object *gem_obj) > > > > return xen_obj->pages; > > > > } > > > > -struct sg_table *xen_drm_front_gem_get_sg_table(struct drm_gem_object *gem_obj) > > > > -{ > > > > - struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj); > > > > - > > > > - if (!xen_obj->pages) > > > > - return ERR_PTR(-ENOMEM); > > > > - > > > > - return drm_prime_pages_to_sg(xen_obj->pages, xen_obj->num_pages); > > > > -} > > > > - > > > > struct drm_gem_object * > > > > xen_drm_front_gem_import_sg_table(struct drm_device *dev, > > > > struct dma_buf_attachment *attach, > > > > @@ -203,7 +237,7 @@ xen_drm_front_gem_import_sg_table(struct drm_device *dev, > > > > if (ret < 0) > > > > return ERR_PTR(ret); > > > > - xen_obj->sgt_imported = sgt; > > > > + xen_obj->sgt = sgt; > > > > ret = drm_prime_sg_to_page_addr_arrays(sgt, xen_obj->pages, > > > > NULL, xen_obj->num_pages); > > > _______________________________________________ > > > dri-devel mailing list > > > dri-devel@lists.freedesktop.org > > > https://lists.freedesktop.org/mailman/listinfo/dri-devel > > [1] https://patchwork.kernel.org/patch/10693787/ > > [2] https://lists.xen.org/archives/html/xen-devel/2018-11/msg02882.html > > [3] https://patchwork.kernel.org/patch/10705853/ > > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch