From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Auger Subject: [PATCH v4 19/22] vfio-pci: Register an iommu fault handler Date: Mon, 18 Feb 2019 14:55:00 +0100 Message-ID: <20190218135504.25048-20-eric.auger@redhat.com> References: <20190218135504.25048-1-eric.auger@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190218135504.25048-1-eric.auger@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: eric.auger.pro@gmail.com, eric.auger@redhat.com, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, joro@8bytes.org, alex.williamson@redhat.com, jacob.jun.pan@linux.intel.com, yi.l.liu@linux.intel.com, jean-philippe.brucker@arm.com, will.deacon@arm.com, robin.murphy@arm.com Cc: marc.zyngier@arm.com, kevin.tian@intel.com, ashok.raj@intel.com List-Id: iommu@lists.linux-foundation.org This patch registers a fault handler which records faults in a circular buffer and then signals an eventfd. This buffer is exposed within the fault region. Signed-off-by: Eric Auger --- drivers/vfio/pci/vfio_pci.c | 49 +++++++++++++++++++++++++++++ drivers/vfio/pci/vfio_pci_private.h | 1 + 2 files changed, 50 insertions(+) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index aaf63e5ca2b6..019c9fd380a5 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -29,6 +29,7 @@ #include #include #include +#include #include "vfio_pci_private.h" @@ -244,6 +245,46 @@ static const struct vfio_pci_regops vfio_pci_fault_prod_regops = { .add_capability = vfio_pci_fault_prod_add_capability, }; +int vfio_pci_iommu_dev_fault_handler(struct iommu_fault_event *evt, void *data) +{ + struct vfio_pci_device *vdev = (struct vfio_pci_device *) data; + struct vfio_region_fault_prod *prod_region = + (struct vfio_region_fault_prod *)vdev->fault_pages; + struct vfio_region_fault_cons *cons_region = + (struct vfio_region_fault_cons *)(vdev->fault_pages + 2 * PAGE_SIZE); + struct iommu_fault *new = + (struct iommu_fault *)(vdev->fault_pages + prod_region->offset + + prod_region->prod * prod_region->entry_size); + int prod, cons, size; + + mutex_lock(&vdev->fault_queue_lock); + + if (!vdev->fault_abi) + goto unlock; + + prod = prod_region->prod; + cons = cons_region->cons; + size = prod_region->nb_entries; + + if (CIRC_SPACE(prod, cons, size) < 1) + goto unlock; + + *new = evt->fault; + prod = (prod + 1) % size; + prod_region->prod = prod; + mutex_unlock(&vdev->fault_queue_lock); + + mutex_lock(&vdev->igate); + if (vdev->dma_fault_trigger) + eventfd_signal(vdev->dma_fault_trigger, 1); + mutex_unlock(&vdev->igate); + return 0; + +unlock: + mutex_unlock(&vdev->fault_queue_lock); + return -EINVAL; +} + static int vfio_pci_init_fault_region(struct vfio_pci_device *vdev) { struct vfio_region_fault_prod *header; @@ -276,6 +317,13 @@ static int vfio_pci_init_fault_region(struct vfio_pci_device *vdev) header = (struct vfio_region_fault_prod *)vdev->fault_pages; header->version = -1; header->offset = PAGE_SIZE; + + ret = iommu_register_device_fault_handler(&vdev->pdev->dev, + vfio_pci_iommu_dev_fault_handler, + vdev); + if (ret) + goto out; + return 0; out: kfree(vdev->fault_pages); @@ -1420,6 +1468,7 @@ static void vfio_pci_remove(struct pci_dev *pdev) vfio_iommu_group_put(pdev->dev.iommu_group, &pdev->dev); kfree(vdev->region); kfree(vdev->fault_pages); + iommu_unregister_device_fault_handler(&pdev->dev); mutex_destroy(&vdev->ioeventfds_lock); kfree(vdev); diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h index 047708aaad66..6f4309c4fe87 100644 --- a/drivers/vfio/pci/vfio_pci_private.h +++ b/drivers/vfio/pci/vfio_pci_private.h @@ -120,6 +120,7 @@ struct vfio_pci_device { int ioeventfds_nr; struct eventfd_ctx *err_trigger; struct eventfd_ctx *req_trigger; + struct eventfd_ctx *dma_fault_trigger; struct mutex fault_queue_lock; int fault_abi; struct list_head dummy_resources_list; -- 2.20.1