record/replay: add network support

This patch adds support of recording and replaying network packets in
irount rr mode.

Record and replay for network interactions is performed with the network filter.
Each backend must have its own instance of the replay filter as follows:
 -netdev user,id=net1 -device rtl8139,netdev=net1
 -object filter-replay,id=replay,netdev=net1

Replay network filter is used to record and replay network packets. While
recording the virtual machine this filter puts all packets coming from
the outer world into the log. In replay mode packets from the log are
injected into the network device. All interactions with network backend
in replay mode are disabled.

v5 changes:
 - using iov_to_buf function instead of loop

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Signed-off-by: Jason Wang <jasowang@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/sysemu/replay.h b/include/sysemu/replay.h
index f80d6d28e8..abb35ca8c9 100644
--- a/include/sysemu/replay.h
+++ b/include/sysemu/replay.h
@@ -39,6 +39,8 @@ enum ReplayCheckpoint {
 };
 typedef enum ReplayCheckpoint ReplayCheckpoint;
 
+typedef struct ReplayNetState ReplayNetState;
+
 extern ReplayMode replay_mode;
 
 /* Replay process control functions */
@@ -137,4 +139,14 @@ void replay_char_read_all_save_error(int res);
 /*! Writes character read_all execution result into the replay log. */
 void replay_char_read_all_save_buf(uint8_t *buf, int offset);
 
+/* Network */
+
+/*! Registers replay network filter attached to some backend. */
+ReplayNetState *replay_register_net(NetFilterState *nfs);
+/*! Unregisters replay network filter. */
+void replay_unregister_net(ReplayNetState *rns);
+/*! Called to write network packet to the replay log. */
+void replay_net_packet_event(ReplayNetState *rns, unsigned flags,
+                             const struct iovec *iov, int iovcnt);
+
 #endif