Introduce ethernet announcement function.

This patch adds an ethernet announce function that will minimize downtime
when doing a live migration.  This code originates from KVM.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5477 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aliguori 2008-10-13 03:13:12 +00:00
parent 5bb7910af0
commit 210f41ba93
2 changed files with 41 additions and 0 deletions

View file

@ -48,6 +48,8 @@ void do_loadvm(const char *name);
void do_delvm(const char *name);
void do_info_snapshots(void);
void qemu_announce_self(void);
void main_loop_wait(int timeout);
int qemu_savevm_state_begin(QEMUFile *f);

39
vl.c
View file

@ -6186,6 +6186,45 @@ void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
}
#endif
#define SELF_ANNOUNCE_ROUNDS 5
#define ETH_P_EXPERIMENTAL 0x01F1 /* just a number */
//#define ETH_P_EXPERIMENTAL 0x0012 /* make it the size of the packet */
#define EXPERIMENTAL_MAGIC 0xf1f23f4f
static int announce_self_create(uint8_t *buf,
uint8_t *mac_addr)
{
uint32_t magic = EXPERIMENTAL_MAGIC;
uint16_t proto = htons(ETH_P_EXPERIMENTAL);
/* FIXME: should we send a different packet (arp/rarp/ping)? */
memset(buf, 0xff, 6); /* h_dst */
memcpy(buf + 6, mac_addr, 6); /* h_src */
memcpy(buf + 12, &proto, 2); /* h_proto */
memcpy(buf + 14, &magic, 4); /* magic */
return 18; /* len */
}
void qemu_announce_self(void)
{
int i, j, len;
VLANState *vlan;
VLANClientState *vc;
uint8_t buf[256];
for (i = 0; i < nb_nics; i++) {
len = announce_self_create(buf, nd_table[i].macaddr);
vlan = nd_table[i].vlan;
for(vc = vlan->first_client; vc != NULL; vc = vc->next) {
if (vc->fd_read == tap_receive) /* send only if tap */
for (j=0; j < SELF_ANNOUNCE_ROUNDS; j++)
vc->fd_read(vc->opaque, buf, len);
}
}
}
/***********************************************************/
/* savevm/loadvm support */