If there are multiple containers and unmap-all fails for some container, we need to remap vaddr for the other containers for which unmap-all succeeded. Recover by walking all flat sections of all containers to restore the vaddr for each. Do so by invoking the vfio listener callback, and passing a new "remap" flag that tells it to restore a mapping without re-allocating new userland data structures.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com> --- hw/vfio/common.c | 79 ++++++++++++++++++++++++++++++++++--------- hw/vfio/cpr.c | 36 ++++++++++++++++++++ include/hw/vfio/vfio-common.h | 2 +- 3 files changed, 100 insertions(+), 17 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index b7b35d4..de821e1 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -895,15 +895,35 @@ static bool vfio_known_safe_misalignment(MemoryRegionSection *section) return true; } +static VFIORamDiscardListener *vfio_find_ram_discard_listener( + VFIOContainer *container, MemoryRegionSection *section) +{ + VFIORamDiscardListener *vrdl; + + QLIST_FOREACH(vrdl, &container->vrdl_list, next) { + if (vrdl->mr == section->mr && + vrdl->offset_within_address_space == + section->offset_within_address_space) { + break; + } + } + + if (!vrdl) { + hw_error("vfio: Trying to sync missing RAM discard listener"); + /* does not return */ + } + return vrdl; +} + static void vfio_listener_region_add(MemoryListener *listener, MemoryRegionSection *section) { VFIOContainer *container = container_of(listener, VFIOContainer, listener); - vfio_container_region_add(container, section); + vfio_container_region_add(container, section, false); } void vfio_container_region_add(VFIOContainer *container, - MemoryRegionSection *section) + MemoryRegionSection *section, bool remap) { hwaddr iova, end; Int128 llend, llsize; @@ -1033,6 +1053,30 @@ void vfio_container_region_add(VFIOContainer *container, int iommu_idx; trace_vfio_listener_region_add_iommu(iova, end); + + /* + * If remap, then VFIO_DMA_UNMAP_FLAG_VADDR has been called, and we + * want to remap the vaddr. vfio_container_region_add was already + * called in the past, so the giommu already exists. Find it and + * replay it, which calls vfio_dma_map further down the stack. + */ + + if (remap) { + hwaddr as_offset = section->offset_within_address_space; + hwaddr iommu_offset = as_offset - section->offset_within_region; + + QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) { + if (giommu->iommu_mr == iommu_mr && + giommu->iommu_offset == iommu_offset) { + memory_region_iommu_replay(giommu->iommu_mr, &giommu->n); + return; + } + } + error_report("Container cannot find iommu region %s offset %lx", + memory_region_name(section->mr), iommu_offset); + goto fail; + } + /* * FIXME: For VFIO iommu types which have KVM acceleration to * avoid bouncing all map/unmaps through qemu this way, this @@ -1083,7 +1127,21 @@ void vfio_container_region_add(VFIOContainer *container, * about changes. */ if (memory_region_has_ram_discard_manager(section->mr)) { - vfio_register_ram_discard_listener(container, section); + /* + * If remap, then VFIO_DMA_UNMAP_FLAG_VADDR has been called, and we + * want to remap the vaddr. vfio_container_region_add was already + * called in the past, so the ram discard listener already exists. + * Call its populate function directly, which calls vfio_dma_map. + */ + if (remap) { + VFIORamDiscardListener *vrdl = + vfio_find_ram_discard_listener(container, section); + if (vrdl->listener.notify_populate(&vrdl->listener, section)) { + error_report("listener.notify_populate failed"); + } + } else { + vfio_register_ram_discard_listener(container, section); + } return; } @@ -1417,19 +1475,8 @@ static int vfio_sync_ram_discard_listener_dirty_bitmap(VFIOContainer *container, MemoryRegionSection *section) { RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr); - VFIORamDiscardListener *vrdl = NULL; - - QLIST_FOREACH(vrdl, &container->vrdl_list, next) { - if (vrdl->mr == section->mr && - vrdl->offset_within_address_space == - section->offset_within_address_space) { - break; - } - } - - if (!vrdl) { - hw_error("vfio: Trying to sync missing RAM discard listener"); - } + VFIORamDiscardListener *vrdl = + vfio_find_ram_discard_listener(container, section); /* * We only want/can synchronize the bitmap for actually mapped parts - diff --git a/hw/vfio/cpr.c b/hw/vfio/cpr.c index 83f7872..1f682cb 100644 --- a/hw/vfio/cpr.c +++ b/hw/vfio/cpr.c @@ -34,6 +34,15 @@ vfio_dma_unmap_vaddr_all(VFIOContainer *container, Error **errp) return 0; } +static int +vfio_region_remap(MemoryRegionSection *section, void *handle, Error **errp) +{ + VFIOContainer *container = handle; + vfio_container_region_add(container, section, true); + container->vaddr_unmapped = false; + return 0; +} + static bool vfio_is_cpr_capable(VFIOContainer *container, Error **errp) { if (!ioctl(container->fd, VFIO_CHECK_EXTENSION, VFIO_UPDATE_VADDR) || @@ -99,6 +108,30 @@ static const VMStateDescription vfio_container_vmstate = { } }; +static void vfio_cpr_fail_notifier(Notifier *notifier, void *data) +{ + MigrationState *s = data; + VFIOContainer *container; + Error *err = NULL; + + if (!migration_has_failed(s) || migrate_mode_of(s) != MIG_MODE_CPR_EXEC) { + return; + } + + container = container_of(notifier, VFIOContainer, cpr_notifier); + if (container->vaddr_unmapped) { + + /* Set reused so vfio_dma_map restores vaddr */ + container->reused = true; + if (address_space_flat_for_each_section(container->space->as, + vfio_region_remap, + container, &err)) { + error_report_err(err); + } + container->reused = false; + } +} + int vfio_cpr_register_container(VFIOContainer *container, Error **errp) { container->cpr_blocker = NULL; @@ -109,6 +142,7 @@ int vfio_cpr_register_container(VFIOContainer *container, Error **errp) vmstate_register(NULL, -1, &vfio_container_vmstate, container); + migration_add_notifier(&container->cpr_notifier, vfio_cpr_fail_notifier); return 0; } @@ -117,4 +151,6 @@ void vfio_cpr_unregister_container(VFIOContainer *container) migrate_del_blocker(&container->cpr_blocker); vmstate_unregister(NULL, &vfio_container_vmstate, container); + + migration_remove_notifier(&container->cpr_notifier); } diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index 17ad9ba..b682645 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -244,7 +244,7 @@ vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id); extern const MemoryListener vfio_prereg_listener; void vfio_listener_register(VFIOContainer *container); void vfio_container_region_add(VFIOContainer *container, - MemoryRegionSection *section); + MemoryRegionSection *section, bool remap); int vfio_spapr_create_window(VFIOContainer *container, MemoryRegionSection *section, -- 1.8.3.1