From d9bcfe28139d190ed9847217dd309296580c2b7e Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Fri, 10 Apr 2015 16:34:13 +0200 Subject: [PATCH 07/14] vfio: Use vfio type1 v2 IOMMU interface Message-id: <20150410163413.15324.90697.stgit@gimli.home> Patchwork-id: 64787 O-Subject: [RHEL7.2 qemu-kvm PATCH 7/8] vfio: Use vfio type1 v2 IOMMU interface Bugzilla: 1210508 RH-Acked-by: Thomas Huth RH-Acked-by: Laszlo Ersek RH-Acked-by: Bandan Das Upstream: 2e6e697e166568fdd09ceaa8c7c8c8c53a5e345b The difference between v1 and v2 is fairly subtle, simply more deterministic behavior for unmaps. The v1 interface allows the user to attempt to unmap sub-regions of previous mappings, returning success with zero size if unable to comply. This was a reflection of the underlying IOMMU API. The v2 interface requires that the user may only unmap fully contained mappings, ie. an unmap cannot intersect or bisect a previous mapping, but may cover multiple mappings. QEMU never made use of the sub-region v1 support anyway, so we can support either v1 or v2. We'll favor v2 since it's newer. Signed-off-by: Alex Williamson Signed-off-by: Miroslav Rezanina --- hw/misc/vfio.c | 8 ++++++-- linux-headers/linux/vfio.h | 1 + 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c index 607dbf4..d06b485 100644 --- a/hw/misc/vfio.c +++ b/hw/misc/vfio.c @@ -3312,7 +3312,10 @@ static int vfio_connect_container(VFIOGroup *group) container = g_malloc0(sizeof(*container)); container->fd = fd; - if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU)) { + if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU) || + ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU)) { + bool v2 = !!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU); + ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd); if (ret) { error_report("vfio: failed to set group container: %m"); @@ -3321,7 +3324,8 @@ static int vfio_connect_container(VFIOGroup *group) return -errno; } - ret = ioctl(fd, VFIO_SET_IOMMU, VFIO_TYPE1_IOMMU); + ret = ioctl(fd, VFIO_SET_IOMMU, + v2 ? VFIO_TYPE1v2_IOMMU : VFIO_TYPE1_IOMMU); if (ret) { error_report("vfio: failed to set iommu for container: %m"); g_free(container); diff --git a/linux-headers/linux/vfio.h b/linux-headers/linux/vfio.h index d341312..7919c76 100644 --- a/linux-headers/linux/vfio.h +++ b/linux-headers/linux/vfio.h @@ -22,6 +22,7 @@ /* Extensions */ #define VFIO_TYPE1_IOMMU 1 +#define VFIO_TYPE1v2_IOMMU 3 /* * The IOCTL interface is designed for extensibility by embedding the -- 1.8.3.1