From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: [PATCH 01/10] xen/swiotlb: Simplify the logic. Date: Mon, 10 Sep 2012 15:45:58 -0400 Message-ID: <1347306367-28669-2-git-send-email-konrad.wilk@oracle.com> References: <1347306367-28669-1-git-send-email-konrad.wilk@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1347306367-28669-1-git-send-email-konrad.wilk@oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, stefano.stabellini@eu.citrix.com Cc: Konrad Rzeszutek Wilk List-Id: xen-devel@lists.xenproject.org Its pretty easy: 1). We only check to see if we need Xen SWIOTLB for PV guests. 2). If swiotlb=force or iommu=soft is set, then Xen SWIOTLB will be enabled. 3). If it is an initial domain, then Xen SWIOTLB will be enabled. 4). Native SWIOTLB must be disabled for PV guests. Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/pci-swiotlb-xen.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c index 967633a..b6a5340 100644 --- a/arch/x86/xen/pci-swiotlb-xen.c +++ b/arch/x86/xen/pci-swiotlb-xen.c @@ -34,19 +34,20 @@ static struct dma_map_ops xen_swiotlb_dma_ops = { int __init pci_xen_swiotlb_detect(void) { + if (!xen_pv_domain()) + return 0; + /* If running as PV guest, either iommu=soft, or swiotlb=force will * activate this IOMMU. If running as PV privileged, activate it * irregardless. */ - if ((xen_initial_domain() || swiotlb || swiotlb_force) && - (xen_pv_domain())) + if ((xen_initial_domain() || swiotlb || swiotlb_force)) xen_swiotlb = 1; /* If we are running under Xen, we MUST disable the native SWIOTLB. * Don't worry about swiotlb_force flag activating the native, as * the 'swiotlb' flag is the only one turning it on. */ - if (xen_pv_domain()) - swiotlb = 0; + swiotlb = 0; return xen_swiotlb; } -- 1.7.7.6