/* netmap_pipe_krings_delete.
*
* There are two cases:
*
* 1) state is
*
* usr1 --> e1 --> e2
*
* and we are e1 (e2 is not registered, so krings_delete cannot be
* called on it);
*
* 2) state is
*
* usr1 --> e1 e2 <-- usr2
*
* and we are either e1 or e2.
*
* In the former case we have to also delete the krings of e2;
* in the latter case we do nothing (note that our krings
* have already been hidden in the unregister callback).
*/
static void
netmap_pipe_krings_delete(struct netmap_adapter *na)
{
struct netmap_pipe_adapter *pna =
(struct netmap_pipe_adapter *)na;
struct netmap_adapter *ona; /* na of the other end */
int i;
if (!pna->peer_ref) {
ND("%p: case 2, kept alive by peer", na);
return;
}
/* case 1) above */
ND("%p: case 1, deleting everyhing", na);
netmap_krings_delete(na); /* also zeroes tx_rings etc. */
/* restore the ring to be deleted on the peer */
ona = &pna->peer->up;
if (ona->tx_rings == NULL) {
/* already deleted, we must be on an
* cleanup-after-error path */
return;
}
for (i = 0; i < ona->num_tx_rings + 1; i++)
ona->tx_rings[i].ring = ona->tx_rings[i].save_ring;
for (i = 0; i < ona->num_rx_rings + 1; i++)
ona->rx_rings[i].ring = ona->rx_rings[i].save_ring;
netmap_mem_rings_delete(ona);
netmap_krings_delete(ona);
}
/* nm_krings_delete callback for monitors */
static void
netmap_monitor_krings_delete(struct netmap_adapter *na)
{
netmap_krings_delete(na);
}
/* netmap_pipe_krings_delete.
*
* There are two cases:
*
* 1) state is
*
* usr1 --> e1 --> e2
*
* and we are e1. We have to create both sets
* of krings.
*
* 2) state is
*
* usr1 --> e1 --> e2
*
* and we are e2. e1 is certainly registered and our
* krings already exist, but they may be hidden.
*/
static int
netmap_pipe_krings_create(struct netmap_adapter *na)
{
struct netmap_pipe_adapter *pna =
(struct netmap_pipe_adapter *)na;
struct netmap_adapter *ona = &pna->peer->up;
int error = 0;
if (pna->peer_ref) {
int i;
/* case 1) above */
D("%p: case 1, create everything", na);
error = netmap_krings_create(na, 0);
if (error)
goto err;
/* we also create all the rings, since we need to
* update the save_ring pointers.
* netmap_mem_rings_create (called by our caller)
* will not create the rings again
*/
error = netmap_mem_rings_create(na);
if (error)
goto del_krings1;
/* update our hidden ring pointers */
for (i = 0; i < na->num_tx_rings + 1; i++)
na->tx_rings[i].save_ring = na->tx_rings[i].ring;
for (i = 0; i < na->num_rx_rings + 1; i++)
na->rx_rings[i].save_ring = na->rx_rings[i].ring;
/* now, create krings and rings of the other end */
error = netmap_krings_create(ona, 0);
if (error)
goto del_rings1;
error = netmap_mem_rings_create(ona);
if (error)
goto del_krings2;
for (i = 0; i < ona->num_tx_rings + 1; i++)
ona->tx_rings[i].save_ring = ona->tx_rings[i].ring;
for (i = 0; i < ona->num_rx_rings + 1; i++)
ona->rx_rings[i].save_ring = ona->rx_rings[i].ring;
/* cross link the krings */
for (i = 0; i < na->num_tx_rings; i++) {
na->tx_rings[i].pipe = pna->peer->up.rx_rings + i;
na->rx_rings[i].pipe = pna->peer->up.tx_rings + i;
pna->peer->up.tx_rings[i].pipe = na->rx_rings + i;
pna->peer->up.rx_rings[i].pipe = na->tx_rings + i;
}
} else {
int i;
/* case 2) above */
/* recover the hidden rings */
ND("%p: case 2, hidden rings", na);
for (i = 0; i < na->num_tx_rings + 1; i++)
na->tx_rings[i].ring = na->tx_rings[i].save_ring;
for (i = 0; i < na->num_rx_rings + 1; i++)
na->rx_rings[i].ring = na->rx_rings[i].save_ring;
}
return 0;
del_krings2:
netmap_krings_delete(ona);
del_rings1:
netmap_mem_rings_delete(na);
del_krings1:
netmap_krings_delete(na);
err:
return error;
}
