diff mbox

[v12,04/18] vfio/platform: return info for bound device

Message ID 1421844606-24751-5-git-send-email-b.reynal@virtualopensystems.com (mailing list archive)
State New, archived
Headers show

Commit Message

Baptiste Reynal Jan. 21, 2015, 12:49 p.m. UTC 
From: Antonios Motakis <a.motakis@virtualopensystems.com>

A VFIO userspace driver will start by opening the VFIO device
that corresponds to an IOMMU group, and will use the ioctl interface
to get the basic device info, such as number of memory regions and
interrupts, and their properties. This patch enables the
VFIO_DEVICE_GET_INFO ioctl call.

Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
---
 drivers/vfio/platform/vfio_platform_common.c | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)
diff mbox

Patch

diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 34d023b..862b43b 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -38,10 +38,27 @@  static int vfio_platform_open(void *device_data)
 static long vfio_platform_ioctl(void *device_data,
 				unsigned int cmd, unsigned long arg)
 {
-	if (cmd == VFIO_DEVICE_GET_INFO)
-		return -EINVAL;
+	struct vfio_platform_device *vdev = device_data;
+	unsigned long minsz;
+
+	if (cmd == VFIO_DEVICE_GET_INFO) {
+		struct vfio_device_info info;
+
+		minsz = offsetofend(struct vfio_device_info, num_irqs);
+
+		if (copy_from_user(&info, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (info.argsz < minsz)
+			return -EINVAL;
+
+		info.flags = vdev->flags;
+		info.num_regions = 0;
+		info.num_irqs = 0;
+
+		return copy_to_user((void __user *)arg, &info, minsz);
 
-	else if (cmd == VFIO_DEVICE_GET_REGION_INFO)
+	} else if (cmd == VFIO_DEVICE_GET_REGION_INFO)
 		return -EINVAL;
 
 	else if (cmd == VFIO_DEVICE_GET_IRQ_INFO)