Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753957AbcDRLAZ (ORCPT ); Mon, 18 Apr 2016 07:00:25 -0400 Received: from e23smtp08.au.ibm.com ([202.81.31.141]:42844 "EHLO e23smtp08.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753621AbcDRLAS (ORCPT ); Mon, 18 Apr 2016 07:00:18 -0400 X-IBM-Helo: d23dlp02.au.ibm.com X-IBM-MailFrom: xyjxie@linux.vnet.ibm.com X-IBM-RcptTo: kvm@vger.kernel.org;linux-doc@vger.kernel.org;linux-kernel@vger.kernel.org;linux-pci@vger.kernel.org From: Yongji Xie To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, iommu@lists.linux-foundation.org, linux-doc@vger.kernel.org Cc: alex.williamson@redhat.com, bhelgaas@google.com, aik@ozlabs.ru, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, joro@8bytes.org, warrier@linux.vnet.ibm.com, zhong@linux.vnet.ibm.com, nikunj@linux.vnet.ibm.com, eric.auger@linaro.org, will.deacon@arm.com, gwshan@linux.vnet.ibm.com, alistair@popple.id.au, ruscur@russell.cc, Yongji Xie Subject: [RFC v6 06/10] PCI: Add a new PCI_BUS_FLAGS_MSI_REMAP flag Date: Mon, 18 Apr 2016 18:58:36 +0800 Message-Id: <1460977120-29367-1-git-send-email-xyjxie@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.9.5 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16041811-0029-0000-0000-0000455E674A Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1472 Lines: 45 We introduce a new pci_bus_flags, PCI_BUS_FLAGS_MSI_REMAP which indicates all devices on the bus are protected by the hardware which supports IRQ remapping(intel naming). This flag will be used to know whether it's safe to expose MSI-X tables of PCI BARs to userspace. Because the capability of IRQ remapping can guarantee the PCI device cannot trigger MSIs that correspond to interrupt IDs of other devices. There is a existing flag for this in the IOMMU space: enum iommu_cap { IOMMU_CAP_CACHE_COHERENCY, ---> IOMMU_CAP_INTR_REMAP, IOMMU_CAP_NOEXEC, }; and Eric also posted a patchset [1] to abstract this capability on MSI controller side for ARM. But it would make sense to have a more common flag like PCI_BUS_FLAGS_MSI_REMAP so that we can use a universal flag to test this capability for different archs on PCI side. [1] http://www.spinics.net/lists/kvm/msg130256.html Signed-off-by: Yongji Xie --- include/linux/pci.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/linux/pci.h b/include/linux/pci.h index 27df4a6..d619228 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -193,6 +193,7 @@ typedef unsigned short __bitwise pci_bus_flags_t; enum pci_bus_flags { PCI_BUS_FLAGS_NO_MSI = (__force pci_bus_flags_t) 1, PCI_BUS_FLAGS_NO_MMRBC = (__force pci_bus_flags_t) 2, + PCI_BUS_FLAGS_MSI_REMAP = (__force pci_bus_flags_t) 4, }; /* These values come from the PCI Express Spec */ -- 1.7.9.5