From 9e7b0442f23a92c27204d6f81a954f30f3126d33 Mon Sep 17 00:00:00 2001 From: Kirti Wankhede Date: Mon, 26 Oct 2020 15:06:25 +0530 Subject: vfio: Add ioctl to get dirty pages bitmap during dma unmap 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 Signed-off-by: Kirti Wankhede Reviewed-by: Neo Jia [aw: fix error_report types, fix cpu_physical_memory_set_dirty_lebitmap() cast] Signed-off-by: Alex Williamson --- hw/vfio/common.c | 97 +++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 93 insertions(+), 4 deletions(-) (limited to 'hw/vfio') diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 43e6e89090..620358a3d8 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -321,11 +321,95 @@ static bool vfio_devices_all_stopped_and_saving(VFIOContainer *container) return true; } +static bool vfio_devices_all_running_and_saving(VFIOContainer *container) +{ + VFIOGroup *group; + VFIODevice *vbasedev; + MigrationState *ms = migrate_get_current(); + + if (!migration_is_setup_or_active(ms->state)) { + return false; + } + + QLIST_FOREACH(group, &container->group_list, container_next) { + QLIST_FOREACH(vbasedev, &group->device_list, next) { + VFIOMigration *migration = vbasedev->migration; + + if (!migration) { + return false; + } + + if ((migration->device_state & VFIO_DEVICE_STATE_SAVING) && + (migration->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)); + + 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%"PRIx64, + (uint64_t)bitmap->size); + ret = -E2BIG; + goto unmap_exit; + } + + bitmap->data = g_try_malloc0(bitmap->size); + if (!bitmap->data) { + ret = -ENOMEM; + goto unmap_exit; + } + + ret = ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, unmap); + if (!ret) { + cpu_physical_memory_set_dirty_lebitmap((unsigned long *)bitmap->data, + iotlb->translated_addr, pages); + } else { + error_report("VFIO_UNMAP_DMA with DIRTY_BITMAP : %m"); + } + + 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), @@ -334,6 +418,11 @@ static int vfio_dma_unmap(VFIOContainer *container, .size = size, }; + if (iotlb && container->dirty_pages_supported && + vfio_devices_all_running_and_saving(container)) { + 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 @@ -381,7 +470,7 @@ 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; } @@ -531,7 +620,7 @@ 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)", @@ -834,7 +923,7 @@ 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)", -- cgit v1.2.3