On Tue, 19 Apr 2011 14:32:59 -0600 Alex Williamson wrote: > When using VFIO to assign a device to a guest, we want to make sure > the device is quiesced on VM reset to stop all DMA within the guest > mapped memory. Add an ioctl which just calls pci_reset_function() > and returns whether it succeeds. > > Signed-off-by: Alex Williamson <alex.william...@redhat.com> > --- > > We've recently needed to add this functionality for current KVM > based device assignment, VFIO should provide a way to do this too. > An example of it being used in the Qemu VFIO driver can be found > here: > > https://github.com/awilliam/qemu-vfio/blob/vfio/hw/vfio.c > > drivers/vfio/vfio_main.c | 4 ++++ > include/linux/vfio.h | 3 +++ > 2 files changed, 7 insertions(+), 0 deletions(-) > > diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c > index 7e427fc..b9bb692 100644 > --- a/drivers/vfio/vfio_main.c > +++ b/drivers/vfio/vfio_main.c > @@ -490,6 +490,10 @@ static long vfio_unl_ioctl(struct file *filep, > ret = vfio_irq_eoi_eventfd(vdev, fd); > break; > > + case VFIO_RESET_FUNCTION: > + ret = pci_reset_function(vdev->pdev); > + break; > + > default: > return -EINVAL; > } > diff --git a/include/linux/vfio.h b/include/linux/vfio.h > index f07d8fe..47d9bb9 100644 > --- a/include/linux/vfio.h > +++ b/include/linux/vfio.h > @@ -215,6 +215,9 @@ struct vfio_dma_map { > /* Re-enable INTx via eventfd */ > #define VFIO_IRQ_EOI_EVENTFD _IOW(';', 110, int) > > +/* Reset PCI function */ > +#define VFIO_RESET_FUNCTION _IO(';', 111) > + > /* > * Reads, writes, and mmaps determine which PCI BAR (or config space) > * from the high level bits of the file offset
I can't find include/linux/vfio.h in linux-next or mainline git, but ioctls need to be documented in Documentation/ioctl/ioctl-number.txt.... --- ~Randy *** Remember to use Documentation/SubmitChecklist when testing your code ***
