slackcoder/qemu - QEMU is a generic and open source machine & userspace emulator and virtualizer

Age	Commit message (Collapse)	Author
2016-09-27	filter-rewriter: rewrite tcp packet to keep secondary connection	Zhang Chen
	We will rewrite tcp packet secondary received and sent. When colo guest is a tcp server. Firstly, client start a tcp handshake. the packet's seq=client_seq, ack=0,flag=SYN. COLO primary guest get this pkt and mirror(filter-mirror) to secondary guest, secondary get it use filter-redirector. Then,primary guest response pkt (seq=primary_seq,ack=client_seq+1,flag=ACK\|SYN). secondary guest response pkt (seq=secondary_seq,ack=client_seq+1,flag=ACK\|SYN). In here,we use filter-rewriter save the secondary_seq to it's tcp connection. Finally handshake,client send pkt (seq=client_seq+1,ack=primary_seq+1,flag=ACK). Here,filter-rewriter can get primary_seq, and rewrite ack from primary_seq+1 to secondary_seq+1, recalculate checksum. So the secondary tcp connection kept good. When we send/recv packet. client send pkt(seq=client_seq+1+data_len,ack=primary_seq+1,flag=ACK\|PSH). filter-rewriter rewrite ack and send to secondary guest. primary guest response pkt (seq=primary_seq+1,ack=client_seq+1+data_len,flag=ACK) secondary guest response pkt (seq=secondary_seq+1,ack=client_seq+1+data_len,flag=ACK) we rewrite secondary guest seq from secondary_seq+1 to primary_seq+1. So tcp connection kept good. In code We use offset( = secondary_seq - primary_seq ) to rewrite seq or ack. handle_primary_tcp_pkt: tcp_pkt->th_ack += offset; handle_secondary_tcp_pkt: tcp_pkt->th_seq -= offset; Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27	filter-rewriter: track connection and parse packet	Zhang Chen
	We use net/colo.h to track connection and parse packet Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27	colo-compare: introduce packet comparison thread	Zhang Chen
	If primary packet is same with secondary packet, we will send primary packet and drop secondary packet, otherwise notify COLO frame to do checkpoint. If primary packet comes but secondary packet does not, after REGULAR_PACKET_CHECK_MS milliseconds we set the primary packet as old_packet,then do a checkpoint. Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27	colo-compare: track connection and enqueue packet	Zhang Chen
	In this patch we use kernel jhash table to track connection, and then enqueue net packet like this: + CompareState ++ \| \| +---------------+ +---------------+ +---------------+ \|conn list +--->conn +--------->conn \| +---------------+ +---------------+ +---------------+ \| \| \| \| \| \| +---------------+ +---v----+ +---v----+ +---v----+ +---v----+ \|primary \| \|secondary \|primary \| \|secondary \|packet \| \|packet + \|packet \| \|packet + +--------+ +--------+ +--------+ +--------+ \| \| \| \| +---v----+ +---v----+ +---v----+ +---v----+ \|primary \| \|secondary \|primary \| \|secondary \|packet \| \|packet + \|packet \| \|packet + +--------+ +--------+ +--------+ +--------+ \| \| \| \| +---v----+ +---v----+ +---v----+ +---v----+ \|primary \| \|secondary \|primary \| \|secondary \|packet \| \|packet + \|packet \| \|packet + +--------+ +--------+ +--------+ +--------+ We use conn_list to record connection info. When we want to enqueue a packet, firstly get the connection from connection_track_table. then push the packet to g_queue(pri/sec) in it's own conn. Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27	net/colo.c: add colo.c to define and handle packet	Zhang Chen
	The net/colo.c is used by colo-compare and filter-rewriter. this can share common data structure like net packet, and other functions. Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Jason Wang <jasowang@redhat.com>