From: Lu Baolu <baolu.lu@linux.intel.com> To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Joerg Roedel <joro@8bytes.org>, Alex Williamson <alex.williamson@redhat.com>, Bjorn Helgaas <bhelgaas@google.com>, Jason Gunthorpe <jgg@nvidia.com>, Christoph Hellwig <hch@infradead.org>, Kevin Tian <kevin.tian@intel.com>, Ashok Raj <ashok.raj@intel.com> Cc: Will Deacon <will@kernel.org>, Robin Murphy <robin.murphy@arm.com>, Dan Williams <dan.j.williams@intel.com>, rafael@kernel.org, Diana Craciun <diana.craciun@oss.nxp.com>, Cornelia Huck <cohuck@redhat.com>, Eric Auger <eric.auger@redhat.com>, Liu Yi L <yi.l.liu@intel.com>, Jacob jun Pan <jacob.jun.pan@intel.com>, Chaitanya Kulkarni <kch@nvidia.com>, Stuart Yoder <stuyoder@gmail.com>, Laurentiu Tudor <laurentiu.tudor@nxp.com>, Thierry Reding <thierry.reding@gmail.com>, David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>, Jonathan Hunter <jonathanh@nvidia.com>, Li Yang <leoyang.li@nxp.com>, Dmitry Osipenko <digetx@gmail.com>, iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Lu Baolu <baolu.lu@linux.intel.com> Subject: [PATCH v8 06/11] PCI: portdrv: Set driver_managed_dma Date: Tue, 8 Mar 2022 13:44:16 +0800 [thread overview] Message-ID: <20220308054421.847385-7-baolu.lu@linux.intel.com> (raw) In-Reply-To: <20220308054421.847385-1-baolu.lu@linux.intel.com> If a switch lacks ACS P2P Request Redirect, a device below the switch can bypass the IOMMU and DMA directly to other devices below the switch, so all the downstream devices must be in the same IOMMU group as the switch itself. The existing VFIO framework allows the portdrv driver to be bound to the bridge while its downstream devices are assigned to user space. The pci_dma_configure() marks the IOMMU group as containing only devices with kernel drivers that manage DMA. Avoid this default behavior for the portdrv driver in order for compatibility with the current VFIO usage. We achieve this by setting ".driver_managed_dma = true" in pci_driver structure. It is safe because the portdrv driver meets below criteria: - This driver doesn't use DMA, as you can't find any related calls like pci_set_master() or any kernel DMA API (dma_map_*() and etc.). - It doesn't use MMIO as you can't find ioremap() or similar calls. It's tolerant to userspace possibly also touching the same MMIO registers via P2P DMA access. Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Suggested-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> --- drivers/pci/pcie/portdrv_pci.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c index 35eca6277a96..6b2adb678c21 100644 --- a/drivers/pci/pcie/portdrv_pci.c +++ b/drivers/pci/pcie/portdrv_pci.c @@ -202,6 +202,8 @@ static struct pci_driver pcie_portdriver = { .err_handler = &pcie_portdrv_err_handler, + .driver_managed_dma = true, + .driver.pm = PCIE_PORTDRV_PM_OPS, }; -- 2.25.1
WARNING: multiple messages have this Message-ID (diff)
From: Lu Baolu <baolu.lu@linux.intel.com> To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Joerg Roedel <joro@8bytes.org>, Alex Williamson <alex.williamson@redhat.com>, Bjorn Helgaas <bhelgaas@google.com>, Jason Gunthorpe <jgg@nvidia.com>, Christoph Hellwig <hch@infradead.org>, Kevin Tian <kevin.tian@intel.com>, Ashok Raj <ashok.raj@intel.com> Cc: kvm@vger.kernel.org, rafael@kernel.org, David Airlie <airlied@linux.ie>, linux-pci@vger.kernel.org, Thierry Reding <thierry.reding@gmail.com>, Diana Craciun <diana.craciun@oss.nxp.com>, Dmitry Osipenko <digetx@gmail.com>, Will Deacon <will@kernel.org>, Stuart Yoder <stuyoder@gmail.com>, Jonathan Hunter <jonathanh@nvidia.com>, Chaitanya Kulkarni <kch@nvidia.com>, Dan Williams <dan.j.williams@intel.com>, Cornelia Huck <cohuck@redhat.com>, linux-kernel@vger.kernel.org, Li Yang <leoyang.li@nxp.com>, iommu@lists.linux-foundation.org, Jacob jun Pan <jacob.jun.pan@intel.com>, Daniel Vetter <daniel@ffwll.ch>, Robin Murphy <robin.murphy@arm.com> Subject: [PATCH v8 06/11] PCI: portdrv: Set driver_managed_dma Date: Tue, 8 Mar 2022 13:44:16 +0800 [thread overview] Message-ID: <20220308054421.847385-7-baolu.lu@linux.intel.com> (raw) In-Reply-To: <20220308054421.847385-1-baolu.lu@linux.intel.com> If a switch lacks ACS P2P Request Redirect, a device below the switch can bypass the IOMMU and DMA directly to other devices below the switch, so all the downstream devices must be in the same IOMMU group as the switch itself. The existing VFIO framework allows the portdrv driver to be bound to the bridge while its downstream devices are assigned to user space. The pci_dma_configure() marks the IOMMU group as containing only devices with kernel drivers that manage DMA. Avoid this default behavior for the portdrv driver in order for compatibility with the current VFIO usage. We achieve this by setting ".driver_managed_dma = true" in pci_driver structure. It is safe because the portdrv driver meets below criteria: - This driver doesn't use DMA, as you can't find any related calls like pci_set_master() or any kernel DMA API (dma_map_*() and etc.). - It doesn't use MMIO as you can't find ioremap() or similar calls. It's tolerant to userspace possibly also touching the same MMIO registers via P2P DMA access. Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Suggested-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> --- drivers/pci/pcie/portdrv_pci.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c index 35eca6277a96..6b2adb678c21 100644 --- a/drivers/pci/pcie/portdrv_pci.c +++ b/drivers/pci/pcie/portdrv_pci.c @@ -202,6 +202,8 @@ static struct pci_driver pcie_portdriver = { .err_handler = &pcie_portdrv_err_handler, + .driver_managed_dma = true, + .driver.pm = PCIE_PORTDRV_PM_OPS, }; -- 2.25.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
next prev parent reply other threads:[~2022-03-08 5:47 UTC|newest] Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-03-08 5:44 [PATCH v8 00/11] Fix BUG_ON in vfio_iommu_group_notifier() Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 5:44 ` [PATCH v8 01/11] iommu: Add DMA ownership management interfaces Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 13:37 ` Robin Murphy 2022-03-08 13:37 ` Robin Murphy 2022-03-08 5:44 ` [PATCH v8 02/11] driver core: Add dma_cleanup callback in bus_type Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 5:44 ` [PATCH v8 03/11] amba: Stop sharing platform_dma_configure() Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 5:44 ` [PATCH v8 04/11] bus: platform, amba, fsl-mc, PCI: Add device DMA ownership management Lu Baolu 2022-03-08 5:44 ` [PATCH v8 04/11] bus: platform,amba,fsl-mc,PCI: " Lu Baolu 2022-03-08 13:39 ` Robin Murphy 2022-03-08 13:39 ` Robin Murphy 2022-03-08 5:44 ` [PATCH v8 05/11] PCI: pci_stub: Set driver_managed_dma Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 5:44 ` Lu Baolu [this message] 2022-03-08 5:44 ` [PATCH v8 06/11] PCI: portdrv: " Lu Baolu 2022-03-08 5:44 ` [PATCH v8 07/11] vfio: Set DMA ownership for VFIO devices Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 5:44 ` [PATCH v8 08/11] vfio: Remove use of vfio_group_viable() Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 5:44 ` [PATCH v8 09/11] vfio: Delete the unbound_list Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 5:44 ` [PATCH v8 10/11] vfio: Remove iommu group notifier Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-08 5:44 ` [PATCH v8 11/11] iommu: Remove iommu group changes notifier Lu Baolu 2022-03-08 5:44 ` Lu Baolu 2022-03-10 9:46 ` [PATCH v8 00/11] Fix BUG_ON in vfio_iommu_group_notifier() Eric Auger 2022-03-10 9:46 ` Eric Auger 2022-03-15 0:21 ` Jason Gunthorpe 2022-03-15 0:21 ` Jason Gunthorpe via iommu 2022-04-08 7:57 ` Joerg Roedel 2022-04-08 7:57 ` Joerg Roedel 2022-04-08 12:22 ` Lu Baolu 2022-04-08 12:22 ` Lu Baolu 2022-04-08 12:23 ` Jason Gunthorpe 2022-04-08 12:23 ` Jason Gunthorpe via iommu 2022-04-08 14:00 ` Joerg Roedel 2022-04-08 14:00 ` Joerg Roedel 2022-04-08 14:17 ` Jason Gunthorpe 2022-04-08 14:17 ` Jason Gunthorpe via iommu 2022-04-08 15:37 ` Joerg Roedel 2022-04-08 15:37 ` Joerg Roedel 2022-04-08 15:59 ` Bjorn Helgaas 2022-04-08 15:59 ` Bjorn Helgaas 2022-04-08 16:07 ` Alex Williamson 2022-04-08 16:07 ` Alex Williamson 2022-04-08 20:24 ` Jason Gunthorpe 2022-04-08 20:24 ` Jason Gunthorpe via iommu
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20220308054421.847385-7-baolu.lu@linux.intel.com \ --to=baolu.lu@linux.intel.com \ --cc=airlied@linux.ie \ --cc=alex.williamson@redhat.com \ --cc=ashok.raj@intel.com \ --cc=bhelgaas@google.com \ --cc=cohuck@redhat.com \ --cc=dan.j.williams@intel.com \ --cc=daniel@ffwll.ch \ --cc=diana.craciun@oss.nxp.com \ --cc=digetx@gmail.com \ --cc=eric.auger@redhat.com \ --cc=gregkh@linuxfoundation.org \ --cc=hch@infradead.org \ --cc=iommu@lists.linux-foundation.org \ --cc=jacob.jun.pan@intel.com \ --cc=jgg@nvidia.com \ --cc=jonathanh@nvidia.com \ --cc=joro@8bytes.org \ --cc=kch@nvidia.com \ --cc=kevin.tian@intel.com \ --cc=kvm@vger.kernel.org \ --cc=laurentiu.tudor@nxp.com \ --cc=leoyang.li@nxp.com \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-pci@vger.kernel.org \ --cc=rafael@kernel.org \ --cc=robin.murphy@arm.com \ --cc=stuyoder@gmail.com \ --cc=thierry.reding@gmail.com \ --cc=will@kernel.org \ --cc=yi.l.liu@intel.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.