This allows auto-assignment of a properly aligned address in guest physical address space. For example, when specifying a 2GB block size for a virtio-mem device with 10GB with a memory setup "-m 4G, 20G", we'll no longer fail when realizing.
Cc: "Michael S. Tsirkin" <m...@redhat.com> Cc: Wei Yang <richardw.y...@linux.intel.com> Cc: Dr. David Alan Gilbert <dgilb...@redhat.com> Cc: Igor Mammedov <imamm...@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.li...@gmail.com> Signed-off-by: David Hildenbrand <da...@redhat.com> --- hw/virtio/virtio-mem-pci.c | 14 ++++++++++++++ hw/virtio/virtio-mem.c | 8 ++++++++ 2 files changed, 22 insertions(+) diff --git a/hw/virtio/virtio-mem-pci.c b/hw/virtio/virtio-mem-pci.c index 590cec041b..2bfa2474fb 100644 --- a/hw/virtio/virtio-mem-pci.c +++ b/hw/virtio/virtio-mem-pci.c @@ -75,6 +75,19 @@ static void virtio_mem_pci_fill_device_info(const MemoryDeviceState *md, info->type = MEMORY_DEVICE_INFO_KIND_VIRTIO_MEM; } +static uint64_t virtio_mem_pci_get_min_alignment(const MemoryDeviceState *md) +{ + /* + * If no block size was configured, returns the default block size. + * Before the device was realized, this might be smaller than the + * final block size (because it ignores the page size of the memory region). + * However, the alignment of the memory region properly considers the + * page size of the memory region. + */ + return object_property_get_uint(OBJECT(md), VIRTIO_MEM_BLOCK_SIZE_PROP, + &error_abort); +} + static void virtio_mem_pci_size_change_notify(Notifier *notifier, void *data) { VirtIOMEMPCI *pci_mem = container_of(notifier, VirtIOMEMPCI, @@ -109,6 +122,7 @@ static void virtio_mem_pci_class_init(ObjectClass *klass, void *data) mdc->get_plugged_size = virtio_mem_pci_get_plugged_size; mdc->get_memory_region = virtio_mem_pci_get_memory_region; mdc->fill_device_info = virtio_mem_pci_fill_device_info; + mdc->get_min_alignment = virtio_mem_pci_get_min_alignment; } static void virtio_mem_pci_instance_init(Object *obj) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 716eddd792..d8222153cf 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -805,6 +805,14 @@ static void virtio_mem_get_block_size(Object *obj, Visitor *v, const char *name, const VirtIOMEM *vmem = VIRTIO_MEM(obj); uint64_t value = vmem->block_size; + /* + * If not configured by the user (and we're not realized yet), use the + * default block size. + */ + if (!value) { + value = virtio_mem_default_block_size(); + } + visit_type_size(v, name, &value, errp); } -- 2.26.2