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 address ranges 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 | 45 ++++++++++++++++++++++++++++++++--- hw/vfio/cpr-legacy.c | 44 ++++++++++++++++++++++++++++++++++ include/hw/vfio/vfio-common.h | 4 +++- include/hw/vfio/vfio-container-base.h | 1 + 4 files changed, 90 insertions(+), 4 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 5c7baad..da2e0ec 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -586,11 +586,12 @@ static void vfio_listener_region_add(MemoryListener *listener, { VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase, listener); - vfio_container_region_add(bcontainer, section); + vfio_container_region_add(bcontainer, section, false); } void vfio_container_region_add(VFIOContainerBase *bcontainer, - MemoryRegionSection *section) + MemoryRegionSection *section, + bool remap) { hwaddr iova, end; Int128 llend, llsize; @@ -626,6 +627,30 @@ void vfio_container_region_add(VFIOContainerBase *bcontainer, 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, &bcontainer->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 @@ -676,7 +701,21 @@ void vfio_container_region_add(VFIOContainerBase *bcontainer, * about changes. */ if (memory_region_has_ram_discard_manager(section->mr)) { - vfio_register_ram_discard_listener(bcontainer, 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(bcontainer, section); + if (vrdl->listener.notify_populate(&vrdl->listener, section)) { + error_report("listener.notify_populate failed"); + } + } else { + vfio_register_ram_discard_listener(bcontainer, section); + } return; } diff --git a/hw/vfio/cpr-legacy.c b/hw/vfio/cpr-legacy.c index bc51ebe..c4b95a8 100644 --- a/hw/vfio/cpr-legacy.c +++ b/hw/vfio/cpr-legacy.c @@ -29,9 +29,18 @@ static bool vfio_dma_unmap_vaddr_all(VFIOContainer *container, Error **errp) error_setg_errno(errp, errno, "vfio_dma_unmap_vaddr_all"); return false; } + container->vaddr_unmapped = true; return true; } +static void vfio_region_remap(MemoryListener *listener, + MemoryRegionSection *section) +{ + VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase, + remap_listener); + vfio_container_region_add(bcontainer, section, true); +} + static bool vfio_can_cpr_exec(VFIOContainer *container, Error **errp) { if (!ioctl(container->fd, VFIO_CHECK_EXTENSION, VFIO_UPDATE_VADDR)) { @@ -95,6 +104,37 @@ static const VMStateDescription vfio_container_vmstate = { } }; +static int vfio_cpr_fail_notifier(NotifierWithReturn *notifier, + MigrationEvent *e, Error **errp) +{ + VFIOContainer *container = + container_of(notifier, VFIOContainer, cpr_exec_notifier); + VFIOContainerBase *bcontainer = &container->bcontainer; + + if (e->type != MIG_EVENT_PRECOPY_FAILED) { + return 0; + } + + if (container->vaddr_unmapped) { + /* + * Force a call to vfio_region_remap for each mapped section by + * temporarily registering a listener, which calls vfio_dma_map + * further down the stack. Set reused so vfio_dma_map restores vaddr. + */ + bcontainer->reused = true; + bcontainer->remap_listener = (MemoryListener) { + .name = "vfio recover", + .region_add = vfio_region_remap + }; + memory_listener_register(&bcontainer->remap_listener, + bcontainer->space->as); + memory_listener_unregister(&bcontainer->remap_listener); + bcontainer->reused = false; + container->vaddr_unmapped = false; + } + return 0; +} + bool vfio_legacy_cpr_register_container(VFIOContainerBase *bcontainer, Error **errp) { @@ -107,6 +147,9 @@ bool vfio_legacy_cpr_register_container(VFIOContainerBase *bcontainer, vmstate_register(NULL, -1, &vfio_container_vmstate, container); + migration_add_notifier_mode(&container->cpr_exec_notifier, + vfio_cpr_fail_notifier, + MIG_MODE_CPR_EXEC); return true; } @@ -115,4 +158,5 @@ void vfio_legacy_cpr_unregister_container(VFIOContainerBase *bcontainer) VFIOContainer *container = VFIO_CONTAINER(bcontainer); vmstate_unregister(NULL, &vfio_container_vmstate, container); + migration_remove_notifier(&container->cpr_exec_notifier); } diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index 7c4283b..1902c8f 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -81,6 +81,8 @@ typedef struct VFIOContainer { VFIOContainerBase bcontainer; int fd; /* /dev/vfio/vfio, empowered by the attached groups */ unsigned iommu_type; + NotifierWithReturn cpr_exec_notifier; + bool vaddr_unmapped; QLIST_HEAD(, VFIOGroup) group_list; } VFIOContainer; @@ -292,7 +294,7 @@ int vfio_get_dirty_bitmap(const VFIOContainerBase *bcontainer, uint64_t iova, uint64_t size, ram_addr_t ram_addr, Error **errp); void vfio_container_region_add(VFIOContainerBase *bcontainer, - MemoryRegionSection *section); + MemoryRegionSection *section, bool remap); void vfio_listener_register(VFIOContainerBase *bcontainer); /* Returns 0 on success, or a negative errno. */ diff --git a/include/hw/vfio/vfio-container-base.h b/include/hw/vfio/vfio-container-base.h index 82ccf0c..3d30365 100644 --- a/include/hw/vfio/vfio-container-base.h +++ b/include/hw/vfio/vfio-container-base.h @@ -37,6 +37,7 @@ typedef struct VFIOContainerBase { Object parent; VFIOAddressSpace *space; MemoryListener listener; + MemoryListener remap_listener; Error *error; bool initialized; bool reused; -- 1.8.3.1