This patch saves the virtio-net device's MAC table information to compare with later during the stop-and-copy phase.
We leave out mac_table.first_multi since it's derived post-load. Note: we store the exact mac_table.in_use value and the MIN macro is only used to bound copy & compare byte spans for safety. Signed-off-by: Jonah Palmer <[email protected]> --- hw/net/virtio-net.c | 34 ++++++++++++++++++++++++++++++++++ include/hw/virtio/virtio-net.h | 8 ++++++++ 2 files changed, 42 insertions(+) diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 4f14bba510..2dd130777e 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -3884,6 +3884,26 @@ static int virtio_net_early_pre_save(void *opaque) /* VirtIONet MAC info snapshot */ memcpy(vnet_mig->mac_early, n->mac, ETH_ALEN); + vnet_mig->mtable_in_use_early = n->mac_table.in_use; + vnet_mig->mtable_uni_overflow_early = n->mac_table.uni_overflow; + vnet_mig->mtable_multi_overflow_early = n->mac_table.multi_overflow; + /* + * Allocate baseline buffer once. Only copy the used slice each time. + * This avoids repeated allocations and keeps memcmp fast + */ + if (!vnet_mig->mtable_macs_early) { + vnet_mig->mtable_macs_early = + g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN); + } + /* + * Copy used portion only. Cap byte span with MIN for safety even if + * a buggy config reports more than capacity. + */ + if (vnet_mig->mtable_in_use_early) { + uint32_t used = MIN(vnet_mig->mtable_in_use_early, (uint32_t)MAC_TABLE_ENTRIES); + size_t bytes = (size_t)used * ETH_ALEN; + memcpy(vnet_mig->mtable_macs_early, n->mac_table.macs, bytes); + } return 0; } @@ -4171,6 +4191,8 @@ static void virtio_net_device_unrealize(DeviceState *dev) g_free(vdev->migration); vdev->migration = NULL; + g_free(n->migration->mtable_macs_early); + n->migration->mtable_macs_early = NULL; g_free(n->migration); n->migration = NULL; @@ -4286,6 +4308,18 @@ static bool virtio_net_has_delta(VirtIONet *n, VirtIODevice *vdev) if (memcmp(n->mac, vnet_mig->mac_early, ETH_ALEN) != 0) { return true; } + if (n->mac_table.in_use != vnet_mig->mtable_in_use_early || + n->mac_table.uni_overflow != vnet_mig->mtable_uni_overflow_early || + n->mac_table.multi_overflow != vnet_mig->mtable_multi_overflow_early) { + return true; + } + if (n->mac_table.in_use) { + uint32_t used = MIN(n->mac_table.in_use, (uint32_t)MAC_TABLE_ENTRIES); + size_t bytes = (size_t)used * ETH_ALEN; + if (memcmp(n->mac_table.macs, vnet_mig->mtable_macs_early, bytes) != 0) { + return true; + } + } /* * Always return true for now until we're able to detect all possible diff --git a/include/hw/virtio/virtio-net.h b/include/hw/virtio/virtio-net.h index 280155366c..1e1f1a3995 100644 --- a/include/hw/virtio/virtio-net.h +++ b/include/hw/virtio/virtio-net.h @@ -170,9 +170,17 @@ typedef struct VirtIONetQueue { /** * struct VirtIONetMigration - VirtIONet migration structure * @mac_early: MAC address early migration snapshot. + * @mtable_in_use_early: In-use MAC table entries. + * @mtable_uni_overflow_early: Unicast overflow MAC table entries. + * @mtable_multi_overflow_early: Multicast overflow MAC table entries. + * @mtable_macs_early: MAC table entries. */ typedef struct VirtIONetMigration { uint8_t mac_early[ETH_ALEN]; + uint32_t mtable_in_use_early; + uint8_t mtable_uni_overflow_early; + uint8_t mtable_multi_overflow_early; + uint8_t *mtable_macs_early; } VirtIONetMigration; struct VirtIONet { -- 2.51.0
