fpga: dfl: fme: add DFL_FPGA_FME_PORT_RELEASE/ASSIGN ioctl support.

In order to support virtualization usage via PCIe SRIOV, this patch
adds two ioctls under FPGA Management Engine (FME) to release and
assign back the port device. In order to safely turn Port from PF
into VF and enable PCIe SRIOV, it requires user to invoke this
PORT_RELEASE ioctl to release port firstly to remove userspace
interfaces, and then configure the PF/VF access register in FME.
After disable SRIOV, it requires user to invoke this PORT_ASSIGN
ioctl to attach the port back to PF.

 Ioctl interfaces:
 * DFL_FPGA_FME_PORT_RELEASE
   Release platform device of given port, it deletes port platform
   device to remove related userspace interfaces on PF. After this
   function, then it's safe to configure PF/VF access mode to VF,
   and enable VFs via SRIOV.

 * DFL_FPGA_FME_PORT_ASSIGN
   Assign platform device of given port back to PF. After configure
   PF/VF access mode to PF, this ioctl adds port platform device
   back to re-enable related userspace interfaces on PF.

Signed-off-by: Zhang Yi Z <yi.z.zhang@intel.com>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Wu Hao <hao.wu@intel.com>
Acked-by: Alan Tull <atull@kernel.org>
Acked-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Link: https://lore.kernel.org/r/1564914022-3710-2-git-send-email-hao.wu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 42 insertions, 0 deletions

diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c
index 0be4635583d5..dfea2dee78c3 100644
--- a/drivers/fpga/dfl-fme-main.c
+++ b/drivers/fpga/dfl-fme-main.c
@@ -16,6 +16,7 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/uaccess.h>
 #include <linux/fpga-dfl.h>
 
 #include "dfl.h"
@@ -104,9 +105,50 @@ static void fme_hdr_uinit(struct platform_device *pdev,
 	device_remove_groups(&pdev->dev, fme_hdr_groups);
 }
 
+static long fme_hdr_ioctl_release_port(struct dfl_feature_platform_data *pdata,
+				       unsigned long arg)
+{
+	struct dfl_fpga_cdev *cdev = pdata->dfl_cdev;
+	int port_id;
+
+	if (get_user(port_id, (int __user *)arg))
+		return -EFAULT;
+
+	return dfl_fpga_cdev_release_port(cdev, port_id);
+}
+
+static long fme_hdr_ioctl_assign_port(struct dfl_feature_platform_data *pdata,
+				      unsigned long arg)
+{
+	struct dfl_fpga_cdev *cdev = pdata->dfl_cdev;
+	int port_id;
+
+	if (get_user(port_id, (int __user *)arg))
+		return -EFAULT;
+
+	return dfl_fpga_cdev_assign_port(cdev, port_id);
+}
+
+static long fme_hdr_ioctl(struct platform_device *pdev,
+			  struct dfl_feature *feature,
+			  unsigned int cmd, unsigned long arg)
+{
+	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
+
+	switch (cmd) {
+	case DFL_FPGA_FME_PORT_RELEASE:
+		return fme_hdr_ioctl_release_port(pdata, arg);
+	case DFL_FPGA_FME_PORT_ASSIGN:
+		return fme_hdr_ioctl_assign_port(pdata, arg);
+	}
+
+	return -ENODEV;
+}
+
 static const struct dfl_feature_ops fme_hdr_ops = {
 	.init = fme_hdr_init,
 	.uinit = fme_hdr_uinit,
+	.ioctl = fme_hdr_ioctl,
 };
 
 static struct dfl_feature_driver fme_feature_drvs[] = {