From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Auger Subject: Re: [PATCH v9 06/19] vfio/platform: return info for bound device Date: Wed, 12 Nov 2014 11:32:28 +0100 Message-ID: <5463373C.2010202@linaro.org> References: <1414433284-31719-1-git-send-email-a.motakis@virtualopensystems.com> <1414433284-31719-7-git-send-email-a.motakis@virtualopensystems.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1414433284-31719-7-git-send-email-a.motakis-lrHrjnjw1UfHK3s98zE1ajGjJy/sRE9J@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Antonios Motakis , kvmarm-FPEHb7Xf0XXUo1n7N8X6UoWGPAHP3yOg@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, alex.williamson-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Cc: VFIO DRIVER , marc.zyngier-5wv7dgnIgG8@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, open list , tech-lrHrjnjw1UfHK3s98zE1ajGjJy/sRE9J@public.gmane.org, christoffer.dall-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org List-Id: iommu@lists.linux-foundation.org On 10/27/2014 07:07 PM, Antonios Motakis wrote: > 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 > --- > drivers/vfio/platform/vfio_platform_common.c | 23 ++++++++++++++++++++--- > 1 file changed, 20 insertions(+), 3 deletions(-) > > diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c > index e0fdbc8..cb20526 100644 > --- a/drivers/vfio/platform/vfio_platform_common.c > +++ b/drivers/vfio/platform/vfio_platform_common.c > @@ -43,10 +43,27 @@ 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; Seems a bit weird to me to enable the modality but returning zeroed values. Shouldn't we put that patch after VFIO_DEVICE_GET_REGION_INFO and VFIO_DEVICE_GET_IRQ_INFO ones? Best Regards Eric > + > + 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) >