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=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 CDEBDC282C0 for ; Fri, 25 Jan 2019 17:19:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D3AB2083B for ; Fri, 25 Jan 2019 17:19:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=tronnes.org header.i=@tronnes.org header.b="hYmFchma" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729059AbfAYRTX (ORCPT ); Fri, 25 Jan 2019 12:19:23 -0500 Received: from smtp.domeneshop.no ([194.63.252.55]:37072 "EHLO smtp.domeneshop.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726252AbfAYRTX (ORCPT ); Fri, 25 Jan 2019 12:19:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tronnes.org; s=ds201810; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To:Subject; bh=3sjfNLszyjWDC/jo15UgIwGUs42l1MlpSXqlFMM/Vzo=; b=hYmFchmaiCYj4Wp8ld9rF7bGNoMG51G0cQhPkSCJjRL30Wh3rZkpKE3U+9iy0lnx9/7H0G+k52Q8LnmcDxSklLyKuj8wmY8In3C7TPDItZHMOHb2TBQXqSEOYvTCe76jdXJyYO6+glNtVtDmlxjyonXrmMA62c8fcgBB+2/evKSbLYe/FngcyLO54O4liMSwpJgRkaToEUDBx4i8eDO8dBaQVrK7E53S+Gi/tMGP6sPzEQdRogAC/ptI/iZNKUb/EGu6zBGdo7Y6FMQbAkErgFK/QJQgTYb8uSEVadcHQFU0+BrqEG3NqZ1cocBjbbNks+oDDi+H97gv4VGKaoxwQw==; Received: from 211.81-166-168.customer.lyse.net ([81.166.168.211]:50359 helo=[192.168.10.176]) by smtp.domeneshop.no with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.84_2) (envelope-from ) id 1gn58S-0002TC-Ht; Fri, 25 Jan 2019 18:19:20 +0100 Subject: Re: [PATCH v3 16/23] drm/qxl: implement prime kmap/kunmap To: Gerd Hoffmann , dri-devel@lists.freedesktop.org Cc: David Airlie , open list , "open list:DRM DRIVER FOR QXL VIRTUAL GPU" , "open list:DRM DRIVER FOR QXL VIRTUAL GPU" , Dave Airlie References: <20190118122020.27596-1-kraxel@redhat.com> <20190118122020.27596-17-kraxel@redhat.com> From: =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= Message-ID: Date: Fri, 25 Jan 2019 18:19:16 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20190118122020.27596-17-kraxel@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Den 18.01.2019 13.20, skrev Gerd Hoffmann: > Generic fbdev emulation needs this. Also: We must keep track of the > number of mappings now, so we don't unmap early in case two users want a > kmap of the same bo. Add a sanity check to destroy callback to make > sure kmap/kunmap is balanced. > > Signed-off-by: Gerd Hoffmann > --- Just a note: You catch the one-to-many kmap type of unbalance, but not the one-too-many kunmap situation. Acked-by: Noralf Trønnes > drivers/gpu/drm/qxl/qxl_drv.h | 1 + > drivers/gpu/drm/qxl/qxl_object.c | 6 ++++++ > drivers/gpu/drm/qxl/qxl_prime.c | 17 +++++++++++++---- > 3 files changed, 20 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/qxl/qxl_drv.h b/drivers/gpu/drm/qxl/qxl_drv.h > index 43c6df9cf9..8c3af1cdbe 100644 > --- a/drivers/gpu/drm/qxl/qxl_drv.h > +++ b/drivers/gpu/drm/qxl/qxl_drv.h > @@ -84,6 +84,7 @@ struct qxl_bo { > struct ttm_bo_kmap_obj kmap; > unsigned int pin_count; > void *kptr; > + unsigned int map_count; > int type; > > /* Constant after initialization */ > diff --git a/drivers/gpu/drm/qxl/qxl_object.c b/drivers/gpu/drm/qxl/qxl_object.c > index 024c8dd317..4928fa6029 100644 > --- a/drivers/gpu/drm/qxl/qxl_object.c > +++ b/drivers/gpu/drm/qxl/qxl_object.c > @@ -36,6 +36,7 @@ static void qxl_ttm_bo_destroy(struct ttm_buffer_object *tbo) > qdev = (struct qxl_device *)bo->gem_base.dev->dev_private; > > qxl_surface_evict(qdev, bo, false); > + WARN_ON_ONCE(bo->map_count > 0); > mutex_lock(&qdev->gem.mutex); > list_del_init(&bo->list); > mutex_unlock(&qdev->gem.mutex); > @@ -131,6 +132,7 @@ int qxl_bo_kmap(struct qxl_bo *bo, void **ptr) > if (bo->kptr) { > if (ptr) > *ptr = bo->kptr; > + bo->map_count++; > return 0; > } > r = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.num_pages, &bo->kmap); > @@ -139,6 +141,7 @@ int qxl_bo_kmap(struct qxl_bo *bo, void **ptr) > bo->kptr = ttm_kmap_obj_virtual(&bo->kmap, &is_iomem); > if (ptr) > *ptr = bo->kptr; > + bo->map_count = 1; > return 0; > } > > @@ -180,6 +183,9 @@ void qxl_bo_kunmap(struct qxl_bo *bo) > { > if (bo->kptr == NULL) > return; > + bo->map_count--; > + if (bo->map_count > 0) > + return; > bo->kptr = NULL; > ttm_bo_kunmap(&bo->kmap); > } > diff --git a/drivers/gpu/drm/qxl/qxl_prime.c b/drivers/gpu/drm/qxl/qxl_prime.c > index a55dece118..708378844c 100644 > --- a/drivers/gpu/drm/qxl/qxl_prime.c > +++ b/drivers/gpu/drm/qxl/qxl_prime.c > @@ -22,7 +22,7 @@ > * Authors: Andreas Pokorny > */ > > -#include "qxl_drv.h" > +#include "qxl_object.h" > > /* Empty Implementations as there should not be any other driver for a virtual > * device that might share buffers with qxl */ > @@ -54,13 +54,22 @@ struct drm_gem_object *qxl_gem_prime_import_sg_table( > > void *qxl_gem_prime_vmap(struct drm_gem_object *obj) > { > - WARN_ONCE(1, "not implemented"); > - return ERR_PTR(-ENOSYS); > + struct qxl_bo *bo = gem_to_qxl_bo(obj); > + void *ptr; > + int ret; > + > + ret = qxl_bo_kmap(bo, &ptr); > + if (ret < 0) > + return ERR_PTR(ret); > + > + return ptr; > } > > void qxl_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr) > { > - WARN_ONCE(1, "not implemented"); > + struct qxl_bo *bo = gem_to_qxl_bo(obj); > + > + qxl_bo_kunmap(bo); > } > > int qxl_gem_prime_mmap(struct drm_gem_object *obj, >