diff options
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/vfio/ccw.c | 9 | ||||
| -rw-r--r-- | hw/vfio/common.c | 23 | ||||
| -rw-r--r-- | hw/vfio/pci.c | 26 | ||||
| -rw-r--r-- | hw/vfio/trace-events | 1 |
4 files changed, 57 insertions, 2 deletions
diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c index 351b305e1a..e96bbdc78b 100644 --- a/hw/vfio/ccw.c +++ b/hw/vfio/ccw.c @@ -349,6 +349,15 @@ static void vfio_ccw_get_device(VFIOGroup *group, VFIOCCWDevice *vcdev, } } + /* + * All vfio-ccw devices are believed to operate in a way compatible with + * memory ballooning, ie. pages pinned in the host are in the current + * working set of the guest driver and therefore never overlap with pages + * available to the guest balloon driver. This needs to be set before + * vfio_get_device() for vfio common to handle the balloon inhibitor. + */ + vcdev->vdev.balloon_allowed = true; + if (vfio_get_device(group, vcdev->cdev.mdevid, &vcdev->vdev, errp)) { goto out_err; } diff --git a/hw/vfio/common.c b/hw/vfio/common.c index a3d758af8d..cd1f4af18a 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -1381,7 +1381,9 @@ void vfio_put_group(VFIOGroup *group) return; } - qemu_balloon_inhibit(false); + if (!group->balloon_allowed) { + qemu_balloon_inhibit(false); + } vfio_kvm_device_del_group(group); vfio_disconnect_container(group); QLIST_REMOVE(group, next); @@ -1417,6 +1419,25 @@ int vfio_get_device(VFIOGroup *group, const char *name, return ret; } + /* + * Clear the balloon inhibitor for this group if the driver knows the + * device operates compatibly with ballooning. Setting must be consistent + * per group, but since compatibility is really only possible with mdev + * currently, we expect singleton groups. + */ + if (vbasedev->balloon_allowed != group->balloon_allowed) { + if (!QLIST_EMPTY(&group->device_list)) { + error_setg(errp, + "Inconsistent device balloon setting within group"); + return -1; + } + + if (!group->balloon_allowed) { + group->balloon_allowed = true; + qemu_balloon_inhibit(false); + } + } + vbasedev->fd = fd; vbasedev->group = group; QLIST_INSERT_HEAD(&group->device_list, vbasedev, next); diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 6cbb8fa054..056f3a887a 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -2804,12 +2804,13 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev); VFIODevice *vbasedev_iter; VFIOGroup *group; - char *tmp, group_path[PATH_MAX], *group_name; + char *tmp, *subsys, group_path[PATH_MAX], *group_name; Error *err = NULL; ssize_t len; struct stat st; int groupid; int i, ret; + bool is_mdev; if (!vdev->vbasedev.sysfsdev) { if (!(~vdev->host.domain || ~vdev->host.bus || @@ -2869,6 +2870,27 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) } } + /* + * Mediated devices *might* operate compatibly with memory ballooning, but + * we cannot know for certain, it depends on whether the mdev vendor driver + * stays in sync with the active working set of the guest driver. Prevent + * the x-balloon-allowed option unless this is minimally an mdev device. + */ + tmp = g_strdup_printf("%s/subsystem", vdev->vbasedev.sysfsdev); + subsys = realpath(tmp, NULL); + g_free(tmp); + is_mdev = (strcmp(subsys, "/sys/bus/mdev") == 0); + free(subsys); + + trace_vfio_mdev(vdev->vbasedev.name, is_mdev); + + if (vdev->vbasedev.balloon_allowed && !is_mdev) { + error_setg(errp, "x-balloon-allowed only potentially compatible " + "with mdev devices"); + vfio_put_group(group); + goto error; + } + ret = vfio_get_device(group, vdev->vbasedev.name, &vdev->vbasedev, errp); if (ret) { vfio_put_group(group); @@ -3170,6 +3192,8 @@ static Property vfio_pci_dev_properties[] = { DEFINE_PROP_BIT("x-igd-opregion", VFIOPCIDevice, features, VFIO_FEATURE_ENABLE_IGD_OPREGION_BIT, false), DEFINE_PROP_BOOL("x-no-mmap", VFIOPCIDevice, vbasedev.no_mmap, false), + DEFINE_PROP_BOOL("x-balloon-allowed", VFIOPCIDevice, + vbasedev.balloon_allowed, false), DEFINE_PROP_BOOL("x-no-kvm-intx", VFIOPCIDevice, no_kvm_intx, false), DEFINE_PROP_BOOL("x-no-kvm-msi", VFIOPCIDevice, no_kvm_msi, false), DEFINE_PROP_BOOL("x-no-kvm-msix", VFIOPCIDevice, no_kvm_msix, false), diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events index d2a74952e3..a85e8662ea 100644 --- a/hw/vfio/trace-events +++ b/hw/vfio/trace-events @@ -39,6 +39,7 @@ vfio_pci_hot_reset_result(const char *name, const char *result) "%s hot reset: % vfio_populate_device_config(const char *name, unsigned long size, unsigned long offset, unsigned long flags) "Device %s config:\n size: 0x%lx, offset: 0x%lx, flags: 0x%lx" vfio_populate_device_get_irq_info_failure(void) "VFIO_DEVICE_GET_IRQ_INFO failure: %m" vfio_realize(const char *name, int group_id) " (%s) group %d" +vfio_mdev(const char *name, bool is_mdev) " (%s) is_mdev %d" vfio_add_ext_cap_dropped(const char *name, uint16_t cap, uint16_t offset) "%s 0x%x@0x%x" vfio_pci_reset(const char *name) " (%s)" vfio_pci_reset_flr(const char *name) "%s FLR/VFIO_DEVICE_RESET" |