On Thu, 2014-06-05 at 15:49 +1000, Alexey Kardashevskiy wrote: > To perform DMA mapping via TCE table correctly, the guest must > know where DMA window is located on the PCI bus. A hypervisor is > expected to provide such information. Since QEMU has no control > over this setting, we need a way to obtain a start address and size > from the host VFIO driver. > > This adds a helper which returns the default DMA window properties > for the specific IOMMU group. The upstream kernel implements this ioctl > already.
Couldn't this be done with Gavin's vfio_pci_container_ioctl()? Thanks, Alex > Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru> > --- > Changes: > v7: > * do not return a group fd from the helper > > v6: > * added dup() to protect group_fd from accidental disposal > > v5: > * reworked to reflect change in vfio_get_group() from one > of previous patches change > > v4: > * fixed possible leaks on error paths > --- > hw/misc/vfio.c | 36 ++++++++++++++++++++++++++++++++++++ > include/hw/misc/vfio.h | 11 +++++++++++ > 2 files changed, 47 insertions(+) > create mode 100644 include/hw/misc/vfio.h > > diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c > index 7437c2e..99141f3 100644 > --- a/hw/misc/vfio.c > +++ b/hw/misc/vfio.c > @@ -39,6 +39,7 @@ > #include "qemu/range.h" > #include "sysemu/kvm.h" > #include "sysemu/sysemu.h" > +#include "hw/misc/vfio.h" > > /* #define DEBUG_VFIO */ > #ifdef DEBUG_VFIO > @@ -4318,3 +4319,38 @@ static void register_vfio_pci_dev_type(void) > } > > type_init(register_vfio_pci_dev_type) > + > +int vfio_container_spapr_get_info(AddressSpace *as, > + int32_t groupid, > + struct vfio_iommu_spapr_tce_info *info) > +{ > + VFIOGroup *group; > + VFIOContainer *container; > + int ret, fd; > + > + group = vfio_get_group(groupid, as); > + if (!group) { > + return -1; > + } > + container = group->container; > + if (!group->container) { > + goto put_group_exit; > + } > + fd = container->fd; > + if (!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_IOMMU)) { > + goto put_group_exit; > + } > + ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, info); > + if (ret) { > + error_report("vfio: failed to get iommu info for container: %s", > + strerror(errno)); > + goto put_group_exit; > + } > + > + return 0; > + > +put_group_exit: > + vfio_put_group(group); > + > + return -1; > +} > diff --git a/include/hw/misc/vfio.h b/include/hw/misc/vfio.h > new file mode 100644 > index 0000000..e82f5a3 > --- /dev/null > +++ b/include/hw/misc/vfio.h > @@ -0,0 +1,11 @@ > +#ifndef VFIO_API_H > +#define VFIO_API_H > + > +#include "qemu/typedefs.h" > +#include <linux/vfio.h> > + > +extern int vfio_container_spapr_get_info(AddressSpace *as, > + int32_t groupid, > + struct vfio_iommu_spapr_tce_info > *info); > + > +#endif