* Kirti Wankhede (kwankh...@nvidia.com) wrote: > With vIOMMU, IO virtual address range can get unmapped while in pre-copy > phase of migration. In that case, unmap ioctl should return pages pinned > in that range and QEMU should find its correcponding guest physical > addresses and report those dirty. > > Suggested-by: Alex Williamson <alex.william...@redhat.com> > Signed-off-by: Kirti Wankhede <kwankh...@nvidia.com> > Reviewed-by: Neo Jia <c...@nvidia.com> > --- > hw/vfio/common.c | 84 > +++++++++++++++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 80 insertions(+), 4 deletions(-) > > diff --git a/hw/vfio/common.c b/hw/vfio/common.c > index 3f7049fbd1b0..2dd9e8b24788 100644 > --- a/hw/vfio/common.c > +++ b/hw/vfio/common.c > @@ -311,11 +311,82 @@ static bool vfio_devices_are_stopped_and_saving(void) > return true; > } > > +static bool vfio_devices_are_running_and_saving(void) > +{ > + VFIOGroup *group; > + VFIODevice *vbasedev; > + > + QLIST_FOREACH(group, &vfio_group_list, next) { > + QLIST_FOREACH(vbasedev, &group->device_list, next) { > + if ((vbasedev->device_state & VFIO_DEVICE_STATE_SAVING) && > + (vbasedev->device_state & VFIO_DEVICE_STATE_RUNNING)) { > + continue; > + } else { > + return false; > + } > + } > + } > + return true; > +} > + > +static int vfio_dma_unmap_bitmap(VFIOContainer *container, > + hwaddr iova, ram_addr_t size, > + IOMMUTLBEntry *iotlb) > +{ > + struct vfio_iommu_type1_dma_unmap *unmap; > + struct vfio_bitmap *bitmap; > + uint64_t pages = TARGET_PAGE_ALIGN(size) >> TARGET_PAGE_BITS; > + int ret; > + > + unmap = g_malloc0(sizeof(*unmap) + sizeof(*bitmap)); > + if (!unmap) { > + return -ENOMEM; > + }
Again that's a fixed size thing so you don't really need to malloc it; g_malloc0 won't return NULL; it'll just assert (which it shouldn't do anyway because those structures are small). Personally I'd just put it on the stack. > + unmap->argsz = sizeof(*unmap) + sizeof(*bitmap); > + unmap->iova = iova; > + unmap->size = size; > + unmap->flags |= VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP; > + bitmap = (struct vfio_bitmap *)&unmap->data; > + > + /* > + * cpu_physical_memory_set_dirty_lebitmap() expects pages in bitmap of > + * TARGET_PAGE_SIZE to mark those dirty. Hence set bitmap_pgsize to > + * TARGET_PAGE_SIZE. > + */ > + > + bitmap->pgsize = TARGET_PAGE_SIZE; > + bitmap->size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) / > + BITS_PER_BYTE; > + > + if (bitmap->size > container->max_dirty_bitmap_size) { > + error_report("UNMAP: Size of bitmap too big 0x%llx", bitmap->size); > + ret = -E2BIG; > + goto unmap_exit; > + } > + > + bitmap->data = g_malloc0(bitmap->size); That one should be a g_try_malloc0 and check it's non-null. > + > + ret = ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, unmap); > + if (!ret) { > + cpu_physical_memory_set_dirty_lebitmap((uint64_t *)bitmap->data, > + iotlb->translated_addr, pages); > + } else { > + error_report("VFIO_UNMAP_DMA with DIRTY_BITMAP : %d", -errno); You're allowed touse %m in hw/vfio for printing the error nicely. > + } > + > + g_free(bitmap->data); > +unmap_exit: > + g_free(unmap); > + return ret; > +} > + > /* > * DMA - Mapping and unmapping for the "type1" IOMMU interface used on x86 > */ > static int vfio_dma_unmap(VFIOContainer *container, > - hwaddr iova, ram_addr_t size) > + hwaddr iova, ram_addr_t size, > + IOMMUTLBEntry *iotlb) > { > struct vfio_iommu_type1_dma_unmap unmap = { > .argsz = sizeof(unmap), > @@ -324,6 +395,11 @@ static int vfio_dma_unmap(VFIOContainer *container, > .size = size, > }; > > + if (iotlb && container->dirty_pages_supported && > + vfio_devices_are_running_and_saving()) { > + return vfio_dma_unmap_bitmap(container, iova, size, iotlb); > + } > + > while (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) { > /* > * The type1 backend has an off-by-one bug in the kernel > (71a7d3d78e3c > @@ -371,7 +447,7 @@ static int vfio_dma_map(VFIOContainer *container, hwaddr > iova, > * the VGA ROM space. > */ > if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0 || > - (errno == EBUSY && vfio_dma_unmap(container, iova, size) == 0 && > + (errno == EBUSY && vfio_dma_unmap(container, iova, size, NULL) == 0 > && > ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0)) { > return 0; > } > @@ -519,7 +595,7 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, > IOMMUTLBEntry *iotlb) > iotlb->addr_mask + 1, vaddr, ret); > } > } else { > - ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1); > + ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1, iotlb); > if (ret) { > error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", " > "0x%"HWADDR_PRIx") = %d (%m)", > @@ -822,7 +898,7 @@ static void vfio_listener_region_del(MemoryListener > *listener, > } > > if (try_unmap) { > - ret = vfio_dma_unmap(container, iova, int128_get64(llsize)); > + ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL); > if (ret) { > error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", " > "0x%"HWADDR_PRIx") = %d (%m)", > -- > 2.7.0 > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK