From 293f496db088f4a674f7246f64ca2968cfeab435 Mon Sep 17 00:00:00 2001
From: Steffen Vogel <post@steffenvogel.de>
Date: Tue, 30 Jan 2018 19:09:19 +0100
Subject: [PATCH 1/3] pci: add function to get currently loaded kernel driver

---
 fpga/include/villas/kernel/pci.h |  3 +++
 fpga/lib/kernel/pci.c            | 21 ++++++++++++++++++++-
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/fpga/include/villas/kernel/pci.h b/fpga/include/villas/kernel/pci.h
index d784cedf8..db6beb0e6 100644
--- a/fpga/include/villas/kernel/pci.h
+++ b/fpga/include/villas/kernel/pci.h
@@ -57,6 +57,9 @@ int pci_device_compare(const struct pci_device *d, const struct pci_device *f);
 
 struct pci_device * pci_lookup_device(struct pci *p, struct pci_device *filter);
 
+/** Get currently loaded driver for device */
+int pci_get_driver(struct pci_device *d, char *buf, size_t buflen);
+
 /** Bind a new LKM to the PCI device */
 int pci_attach_driver(struct pci_device *d, const char *driver);
 
diff --git a/fpga/lib/kernel/pci.c b/fpga/lib/kernel/pci.c
index 56a8c17bd..e4d6793ba 100644
--- a/fpga/lib/kernel/pci.c
+++ b/fpga/lib/kernel/pci.c
@@ -254,10 +254,29 @@ struct pci_device * pci_lookup_device(struct pci *p, struct pci_device *f)
 	return list_search(&p->devices, (cmp_cb_t) pci_device_compare, (void *) f);
 }
 
+int pci_get_driver(struct pci_device *d, char *buf, size_t buflen)
+{
+	int ret;
+	char sysfs[1024], syml[1024];
+
+	snprintf(sysfs, sizeof(sysfs), "%s/bus/pci/devices/%04x:%02x:%02x.%x/driver", SYSFS_PATH,
+		d->slot.domain, d->slot.bus, d->slot.device, d->slot.function);
+
+	ret = readlink(sysfs, syml, sizeof(syml));
+	if (ret < 0)
+		return ret;
+
+	char *driver = basename(syml);
+
+	strncpy(buf, driver, buflen);
+
+	return 0;
+}
+
 int pci_attach_driver(struct pci_device *d, const char *driver)
 {
 	FILE *f;
-	char fn[256];
+	char fn[1024];
 
 	/* Add new ID to driver */
 	snprintf(fn, sizeof(fn), "%s/bus/pci/drivers/%s/new_id", SYSFS_PATH, driver);

From 3047f5bb7a2b34646c6b587c83da13b84401803b Mon Sep 17 00:00:00 2001
From: Steffen Vogel <post@steffenvogel.de>
Date: Tue, 30 Jan 2018 19:09:56 +0100
Subject: [PATCH 2/3] vfio: only rebind pci device to VFIO driver if not
 already bound

---
 fpga/lib/kernel/vfio.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/fpga/lib/kernel/vfio.c b/fpga/lib/kernel/vfio.c
index 018f42dcf..0c0de58d4 100644
--- a/fpga/lib/kernel/vfio.c
+++ b/fpga/lib/kernel/vfio.c
@@ -229,10 +229,13 @@ int vfio_pci_attach(struct vfio_device *d, struct vfio_container *c, struct pci_
 	if (kernel_module_load("vfio_pci"))
 		error("Failed to load kernel driver: %s", "vfio_pci");
 
-	/* Bind PCI card to vfio-pci driver*/
-	ret = pci_attach_driver(pdev, "vfio-pci");
-	if (ret)
-		error("Failed to attach device to driver");
+	/* Bind PCI card to vfio-pci driver if not already bound */
+	ret = pci_get_driver(pdev, name, sizeof(name));
+	if (ret || strcmp(name, "vfio-pci")) {
+		ret = pci_attach_driver(pdev, "vfio-pci");
+		if (ret)
+			error("Failed to attach device to driver");
+	}
 
 	/* Get IOMMU group of device */
 	int index = pci_get_iommu_group(pdev);

From 4f86b98fdd7c6dda813b9f9380780a0b010c55df Mon Sep 17 00:00:00 2001
From: Steffen Vogel <post@steffenvogel.de>
Date: Tue, 30 Jan 2018 19:15:45 +0100
Subject: [PATCH 3/3] add script to configure system for non-root access to
 FPGA

---
 fpga/scripts/non_root.sh | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 fpga/scripts/non_root.sh

diff --git a/fpga/scripts/non_root.sh b/fpga/scripts/non_root.sh
new file mode 100644
index 000000000..22e4f941d
--- /dev/null
+++ b/fpga/scripts/non_root.sh
@@ -0,0 +1,18 @@
+#!/bin/bash
+
+IOMMU_GROUP=24
+PCI_BDF="0000:03:00.0"
+
+modprobe vfio
+modprobe vfio_pci
+
+echo "10ee 7022" > /sys/bus/pci/drivers/vfio-pci/new_id
+echo ${PCI_BDF} > /sys/bus/pci/drivers/vfio-pci/bind
+
+groupadd -f fpga
+usermod -G fpga -a svg
+
+chgrp fpga /dev/vfio/${IOMMU_GROUP}
+chmod g+rw /dev/vfio/${IOMMU_GROUP}
+
+