From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753432AbaH2IB4 (ORCPT ); Fri, 29 Aug 2014 04:01:56 -0400 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:52021 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753148AbaH2H7d (ORCPT ); Fri, 29 Aug 2014 03:59:33 -0400 From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Cc: Alexey Kardashevskiy , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Alex Williamson , Gavin Shan , linux-kernel@vger.kernel.org, cbe-oss-dev@lists.ozlabs.org, kvm@vger.kernel.org, linux-api@vger.kernel.org Subject: [PATCH 07/13] powerpc/powernv: Do not set "read" flag if direction==DMA_NONE Date: Fri, 29 Aug 2014 17:59:10 +1000 Message-Id: <1409299156-618-8-git-send-email-aik@ozlabs.ru> X-Mailer: git-send-email 2.0.0 In-Reply-To: <1409299156-618-1-git-send-email-aik@ozlabs.ru> References: <1409299156-618-1-git-send-email-aik@ozlabs.ru> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14082907-1618-0000-0000-000000D19C8D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Normally a bitmap from the iommu_table is used to track what TCE entry is in use. Since we are going to use iommu_table without its locks and do xchg() instead, it becomes essential not to put bits which are not implied in the direction flag. Signed-off-by: Alexey Kardashevskiy --- arch/powerpc/platforms/powernv/pci.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c index deddcad..ab79e2d 100644 --- a/arch/powerpc/platforms/powernv/pci.c +++ b/arch/powerpc/platforms/powernv/pci.c @@ -628,10 +628,18 @@ static int pnv_tce_build(struct iommu_table *tbl, long index, long npages, __be64 *tcep, *tces; u64 rpn; - proto_tce = TCE_PCI_READ; // Read allowed - - if (direction != DMA_TO_DEVICE) - proto_tce |= TCE_PCI_WRITE; + switch (direction) { + case DMA_BIDIRECTIONAL: + case DMA_FROM_DEVICE: + proto_tce = TCE_PCI_READ | TCE_PCI_WRITE; + break; + case DMA_TO_DEVICE: + proto_tce = TCE_PCI_READ; + break; + default: + proto_tce = 0; + break; + } tces = tcep = ((__be64 *)tbl->it_base) + index - tbl->it_offset; rpn = __pa(uaddr) >> tbl->it_page_shift; -- 2.0.0