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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 D90ECC2D0A3 for ; Tue, 3 Nov 2020 22:04:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8F2A922277 for ; Tue, 3 Nov 2020 22:04:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604441097; bh=RZIrB93nw6gEeMXkrI60E6xeh8zdRZi8nCXx6532nqA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=npKbTsD5vlw2E7Evfn5GnzUZeZk1T9t8lkjMBwvCaFjoTSe9px81zcjgN/x5rkr7n p5HHUK0q0j0VmR5ehQ68xKbx0BbPfinuRazw6EMTevECiqTBQkcjC3FPLlR+InNxca EHOoANYdF48sxc/8+a2Dbcyz3mzBRnwdyo9IB4zg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730848AbgKCWE4 (ORCPT ); Tue, 3 Nov 2020 17:04:56 -0500 Received: from mail.kernel.org ([198.145.29.99]:56444 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730644AbgKCUnJ (ORCPT ); Tue, 3 Nov 2020 15:43:09 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BA474223AC; Tue, 3 Nov 2020 20:43:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604436189; bh=RZIrB93nw6gEeMXkrI60E6xeh8zdRZi8nCXx6532nqA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l9lo6nDCGK4LUCqIkl4cRZ8ll2Ajy5bCtZEGwaXu7csg4kbu4y6a2qZYpl+mhKuQU ZF7GPLuVmfEy6gKaXwf+ZTIsDvdh9lHNCp7WjJvwv1JVQJ+EA1lIVbFBJWgBxLh+vm Ob8g6vrqZ88+Lhc2EFKPpb8bTlHK9Gop6pnV1phw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marek Szyprowski , Qiang Yu , Sasha Levin Subject: [PATCH 5.9 103/391] drm: lima: fix common struct sg_table related issues Date: Tue, 3 Nov 2020 21:32:34 +0100 Message-Id: <20201103203353.780196185@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201103203348.153465465@linuxfoundation.org> References: <20201103203348.153465465@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marek Szyprowski [ Upstream commit c3d9c17f486d5c54940487dc31a54ebfdeeb371a ] The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function returns the number of the created entries in the DMA address space. However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and dma_unmap_sg must be called with the original number of the entries passed to the dma_map_sg(). struct sg_table is a common structure used for describing a non-contiguous memory buffer, used commonly in the DRM and graphics subsystems. It consists of a scatterlist with memory pages and DMA addresses (sgl entry), as well as the number of scatterlist entries: CPU pages (orig_nents entry) and DMA mapped pages (nents entry). It turned out that it was a common mistake to misuse nents and orig_nents entries, calling DMA-mapping functions with a wrong number of entries or ignoring the number of mapped entries returned by the dma_map_sg() function. To avoid such issues, lets use a common dma-mapping wrappers operating directly on the struct sg_table objects and use scatterlist page iterators where possible. This, almost always, hides references to the nents and orig_nents entries, making the code robust, easier to follow and copy/paste safe. Signed-off-by: Marek Szyprowski Reviewed-by: Qiang Yu Signed-off-by: Sasha Levin --- drivers/gpu/drm/lima/lima_gem.c | 11 ++++++++--- drivers/gpu/drm/lima/lima_vm.c | 5 ++--- 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/lima/lima_gem.c b/drivers/gpu/drm/lima/lima_gem.c index 155f2b4b4030a..11223fe348dfe 100644 --- a/drivers/gpu/drm/lima/lima_gem.c +++ b/drivers/gpu/drm/lima/lima_gem.c @@ -69,8 +69,7 @@ int lima_heap_alloc(struct lima_bo *bo, struct lima_vm *vm) return ret; if (bo->base.sgt) { - dma_unmap_sg(dev, bo->base.sgt->sgl, - bo->base.sgt->nents, DMA_BIDIRECTIONAL); + dma_unmap_sgtable(dev, bo->base.sgt, DMA_BIDIRECTIONAL, 0); sg_free_table(bo->base.sgt); } else { bo->base.sgt = kmalloc(sizeof(*bo->base.sgt), GFP_KERNEL); @@ -80,7 +79,13 @@ int lima_heap_alloc(struct lima_bo *bo, struct lima_vm *vm) } } - dma_map_sg(dev, sgt.sgl, sgt.nents, DMA_BIDIRECTIONAL); + ret = dma_map_sgtable(dev, &sgt, DMA_BIDIRECTIONAL, 0); + if (ret) { + sg_free_table(&sgt); + kfree(bo->base.sgt); + bo->base.sgt = NULL; + return ret; + } *bo->base.sgt = sgt; diff --git a/drivers/gpu/drm/lima/lima_vm.c b/drivers/gpu/drm/lima/lima_vm.c index 5b92fb82674a9..2b2739adc7f53 100644 --- a/drivers/gpu/drm/lima/lima_vm.c +++ b/drivers/gpu/drm/lima/lima_vm.c @@ -124,7 +124,7 @@ int lima_vm_bo_add(struct lima_vm *vm, struct lima_bo *bo, bool create) if (err) goto err_out1; - for_each_sg_dma_page(bo->base.sgt->sgl, &sg_iter, bo->base.sgt->nents, 0) { + for_each_sgtable_dma_page(bo->base.sgt, &sg_iter, 0) { err = lima_vm_map_page(vm, sg_page_iter_dma_address(&sg_iter), bo_va->node.start + offset); if (err) @@ -298,8 +298,7 @@ int lima_vm_map_bo(struct lima_vm *vm, struct lima_bo *bo, int pageoff) mutex_lock(&vm->lock); base = bo_va->node.start + (pageoff << PAGE_SHIFT); - for_each_sg_dma_page(bo->base.sgt->sgl, &sg_iter, - bo->base.sgt->nents, pageoff) { + for_each_sgtable_dma_page(bo->base.sgt, &sg_iter, pageoff) { err = lima_vm_map_page(vm, sg_page_iter_dma_address(&sg_iter), base + offset); if (err) -- 2.27.0