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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 01B11C31E40 for ; Tue, 6 Aug 2019 22:46:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C060721738 for ; Tue, 6 Aug 2019 22:46:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="O9b4Y0AL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727266AbfHFWqA (ORCPT ); Tue, 6 Aug 2019 18:46:00 -0400 Received: from mail-oi1-f196.google.com ([209.85.167.196]:38534 "EHLO mail-oi1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726069AbfHFWqA (ORCPT ); Tue, 6 Aug 2019 18:46:00 -0400 Received: by mail-oi1-f196.google.com with SMTP id v186so69070818oie.5 for ; Tue, 06 Aug 2019 15:45:59 -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=dt4aiSrkRERX1Bfp8k3z3Xn3AM67tm5WpoUKfvE2/lw=; b=O9b4Y0ALJLQfgNjuXwl/+eKwVHhroXtjWSmezluXfLLMNQgPp8TuqVh0vlpMLoyrrE /flMTEyZWMQJActUEFPwrTzmTj+dZNXTnabHvzKghqZFM4hLa2Lsib9oV2afBxCmnJ3d WtSZKeJhJ1YQiWQ2GhBmifWC90Bdabjk6RalM= 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=dt4aiSrkRERX1Bfp8k3z3Xn3AM67tm5WpoUKfvE2/lw=; b=uluVXexzMGvHBCLTtcqR3lyvEcskgXalEgsIASS0txRGAlW44Lgrci7CFlK7O49AwF mplJKnSZ2u6nIDxuS+gC9pN4K1noQ55Ud1KYuDwRuwo00o6vFsT5wlegjq9OJdRJ6aRR 4qmVeV9nxj0zl3UzvS+y2iHBVVlsHQbEfBpN3dlhQBwUbmLevZCYagKkS3QTIRKaSaXK bUksDuSCsYY7ixSuLG4Y0Lr1l2qF0bSxz9hffPcjBOuRIRTcYPfaOqcSoQSChs4zaeeT H/AqRVnL03OprxqV2yoF9QDeH9xLuLdQ0Y246Q0l30LbYf/E7thCNMYlg3Craowi6Z45 e6TQ== X-Gm-Message-State: APjAAAVdZm3IvabxF3/mUEg/Sp7O7ywkKfSKtnOPcVk8YUM34jbjWnJJ exJeHb+7ReH5WNI5pkH7sFLxxm61gfg53uGeBUJeQQ== X-Google-Smtp-Source: APXvYqxLlSOHTSyILonwS6wVkz5p/KQXRjYB80bDESDnW0Pe43KmYkFcn08gNzz1iuCYMODwuRL6JnBVVREOF+NHWXY= X-Received: by 2002:a05:6638:303:: with SMTP id w3mr6640136jap.103.1565131559097; Tue, 06 Aug 2019 15:45:59 -0700 (PDT) MIME-Version: 1.0 References: <20190806213319.19203-1-sashal@kernel.org> <20190806213319.19203-37-sashal@kernel.org> In-Reply-To: <20190806213319.19203-37-sashal@kernel.org> From: Rob Clark Date: Tue, 6 Aug 2019 15:45:48 -0700 Message-ID: Subject: Re: [PATCH AUTOSEL 5.2 37/59] drm/vgem: fix cache synchronization on arm/arm64 To: Sasha Levin Cc: LKML , stable@vger.kernel.org, Daniel Vetter , Sean Paul , dri-devel Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org please don't queue this one for stable branches.. it was causing problems in intel CI BR, -R On Tue, Aug 6, 2019 at 2:34 PM Sasha Levin wrote: > > From: Rob Clark > > [ Upstream commit 7e9e5ead55beacc11116b3fb90b0de6e7cf55a69 ] > > drm_cflush_pages() is no-op on arm/arm64. But instead we can use > dma_sync API. > > Fixes failures w/ vgem_test. > > Acked-by: Daniel Vetter > Signed-off-by: Rob Clark > Signed-off-by: Sean Paul > Link: https://patchwork.freedesktop.org/patch/msgid/20190717211542.30482-1-robdclark@gmail.com > Signed-off-by: Sasha Levin > --- > drivers/gpu/drm/vgem/vgem_drv.c | 130 ++++++++++++++++++++------------ > 1 file changed, 83 insertions(+), 47 deletions(-) > > diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c > index 11a8f99ba18c5..fc04803ff4035 100644 > --- a/drivers/gpu/drm/vgem/vgem_drv.c > +++ b/drivers/gpu/drm/vgem/vgem_drv.c > @@ -47,10 +47,16 @@ static struct vgem_device { > struct platform_device *platform; > } *vgem_device; > > +static void sync_and_unpin(struct drm_vgem_gem_object *bo); > +static struct page **pin_and_sync(struct drm_vgem_gem_object *bo); > + > static void vgem_gem_free_object(struct drm_gem_object *obj) > { > struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj); > > + if (!obj->import_attach) > + sync_and_unpin(vgem_obj); > + > kvfree(vgem_obj->pages); > mutex_destroy(&vgem_obj->pages_lock); > > @@ -78,40 +84,15 @@ static vm_fault_t vgem_gem_fault(struct vm_fault *vmf) > return VM_FAULT_SIGBUS; > > mutex_lock(&obj->pages_lock); > + if (!obj->pages) > + pin_and_sync(obj); > if (obj->pages) { > get_page(obj->pages[page_offset]); > vmf->page = obj->pages[page_offset]; > ret = 0; > } > mutex_unlock(&obj->pages_lock); > - if (ret) { > - struct page *page; > - > - page = shmem_read_mapping_page( > - file_inode(obj->base.filp)->i_mapping, > - page_offset); > - if (!IS_ERR(page)) { > - vmf->page = page; > - ret = 0; > - } else switch (PTR_ERR(page)) { > - case -ENOSPC: > - case -ENOMEM: > - ret = VM_FAULT_OOM; > - break; > - case -EBUSY: > - ret = VM_FAULT_RETRY; > - break; > - case -EFAULT: > - case -EINVAL: > - ret = VM_FAULT_SIGBUS; > - break; > - default: > - WARN_ON(PTR_ERR(page)); > - ret = VM_FAULT_SIGBUS; > - break; > - } > > - } > return ret; > } > > @@ -277,32 +258,93 @@ static const struct file_operations vgem_driver_fops = { > .release = drm_release, > }; > > -static struct page **vgem_pin_pages(struct drm_vgem_gem_object *bo) > +/* Called under pages_lock, except in free path (where it can't race): */ > +static void sync_and_unpin(struct drm_vgem_gem_object *bo) > { > - mutex_lock(&bo->pages_lock); > - if (bo->pages_pin_count++ == 0) { > - struct page **pages; > + struct drm_device *dev = bo->base.dev; > + > + if (bo->table) { > + dma_sync_sg_for_cpu(dev->dev, bo->table->sgl, > + bo->table->nents, DMA_BIDIRECTIONAL); > + sg_free_table(bo->table); > + kfree(bo->table); > + bo->table = NULL; > + } > + > + if (bo->pages) { > + drm_gem_put_pages(&bo->base, bo->pages, true, true); > + bo->pages = NULL; > + } > +} > + > +static struct page **pin_and_sync(struct drm_vgem_gem_object *bo) > +{ > + struct drm_device *dev = bo->base.dev; > + int npages = bo->base.size >> PAGE_SHIFT; > + struct page **pages; > + struct sg_table *sgt; > + > + WARN_ON(!mutex_is_locked(&bo->pages_lock)); > + > + pages = drm_gem_get_pages(&bo->base); > + if (IS_ERR(pages)) { > + bo->pages_pin_count--; > + mutex_unlock(&bo->pages_lock); > + return pages; > + } > > - pages = drm_gem_get_pages(&bo->base); > - if (IS_ERR(pages)) { > - bo->pages_pin_count--; > - mutex_unlock(&bo->pages_lock); > - return pages; > - } > + sgt = drm_prime_pages_to_sg(pages, npages); > + if (IS_ERR(sgt)) { > + dev_err(dev->dev, > + "failed to allocate sgt: %ld\n", > + PTR_ERR(bo->table)); > + drm_gem_put_pages(&bo->base, pages, false, false); > + mutex_unlock(&bo->pages_lock); > + return ERR_CAST(bo->table); > + } > + > + /* > + * Flush the object from the CPU cache so that importers > + * can rely on coherent indirect access via the exported > + * dma-address. > + */ > + dma_sync_sg_for_device(dev->dev, sgt->sgl, > + sgt->nents, DMA_BIDIRECTIONAL); > + > + bo->pages = pages; > + bo->table = sgt; > + > + return pages; > +} > + > +static struct page **vgem_pin_pages(struct drm_vgem_gem_object *bo) > +{ > + struct page **pages; > > - bo->pages = pages; > + mutex_lock(&bo->pages_lock); > + if (bo->pages_pin_count++ == 0 && !bo->pages) { > + pages = pin_and_sync(bo); > + } else { > + WARN_ON(!bo->pages); > + pages = bo->pages; > } > mutex_unlock(&bo->pages_lock); > > - return bo->pages; > + return pages; > } > > static void vgem_unpin_pages(struct drm_vgem_gem_object *bo) > { > + /* > + * We shouldn't hit this for imported bo's.. in the import > + * case we don't own the scatter-table > + */ > + WARN_ON(bo->base.import_attach); > + > mutex_lock(&bo->pages_lock); > if (--bo->pages_pin_count == 0) { > - drm_gem_put_pages(&bo->base, bo->pages, true, true); > - bo->pages = NULL; > + WARN_ON(!bo->table); > + sync_and_unpin(bo); > } > mutex_unlock(&bo->pages_lock); > } > @@ -310,18 +352,12 @@ static void vgem_unpin_pages(struct drm_vgem_gem_object *bo) > static int vgem_prime_pin(struct drm_gem_object *obj) > { > struct drm_vgem_gem_object *bo = to_vgem_bo(obj); > - long n_pages = obj->size >> PAGE_SHIFT; > struct page **pages; > > pages = vgem_pin_pages(bo); > if (IS_ERR(pages)) > return PTR_ERR(pages); > > - /* Flush the object from the CPU cache so that importers can rely > - * on coherent indirect access via the exported dma-address. > - */ > - drm_clflush_pages(pages, n_pages); > - > return 0; > } > > -- > 2.20.1 >