static void xennet_tx_buf_gc(struct net_device *dev)
{
RING_IDX cons, prod;
unsigned short id;
struct netfront_info *np = netdev_priv(dev);
struct sk_buff *skb;
BUG_ON(!netif_carrier_ok(dev));
do {
prod = np->tx.sring->rsp_prod;
rmb(); /* Ensure we see responses up to 'rp'. */
for (cons = np->tx.rsp_cons; cons != prod; cons++) {
struct xen_netif_tx_response *txrsp;
txrsp = RING_GET_RESPONSE(&np->tx, cons);
if (txrsp->status == NETIF_RSP_NULL)
continue;
id = txrsp->id;
skb = np->tx_skbs[id].skb;
if (unlikely(gnttab_query_foreign_access(
np->grant_tx_ref[id]) != 0)) {
printk(KERN_ALERT "xennet_tx_buf_gc: warning "
"-- grant still in use by backend "
"domain.\n");
BUG();
}
gnttab_end_foreign_access_ref(
np->grant_tx_ref[id], GNTMAP_readonly);
gnttab_release_grant_reference(
&np->gref_tx_head, np->grant_tx_ref[id]);
np->grant_tx_ref[id] = GRANT_INVALID_REF;
add_id_to_freelist(&np->tx_skb_freelist, np->tx_skbs, id);
dev_kfree_skb_irq(skb);
}
np->tx.rsp_cons = prod;
/*
* Set a new event, then check for race with update of tx_cons.
* Note that it is essential to schedule a callback, no matter
* how few buffers are pending. Even if there is space in the
* transmit ring, higher layers may be blocked because too much
* data is outstanding: in such cases notification from Xen is
* likely to be the only kick that we'll get.
*/
np->tx.sring->rsp_event =
prod + ((np->tx.sring->req_prod - prod) >> 1) + 1;
mb(); /* update shared area */
} while ((cons == prod) && (prod != np->tx.sring->rsp_prod));
xennet_maybe_wake_tx(dev);
}
int net_accel_ungrant_page(grant_ref_t gntref)
{
if (unlikely(gnttab_query_foreign_access(gntref) != 0)) {
EPRINTK("%s: remote domain still using grant %d\n", __FUNCTION__,
gntref);
return -EBUSY;
}
gnttab_end_foreign_access(gntref, 0);
return 0;
}
static void xennet_tx_buf_gc(struct net_device *dev)
{
RING_IDX cons, prod;
unsigned short id;
struct netfront_info *np = netdev_priv(dev);
struct sk_buff *skb;
BUG_ON(!netif_carrier_ok(dev));
do {
prod = np->tx.sring->rsp_prod;
rmb();
for (cons = np->tx.rsp_cons; cons != prod; cons++) {
struct xen_netif_tx_response *txrsp;
txrsp = RING_GET_RESPONSE(&np->tx, cons);
if (txrsp->status == NETIF_RSP_NULL)
continue;
id = txrsp->id;
skb = np->tx_skbs[id].skb;
if (unlikely(gnttab_query_foreign_access(
np->grant_tx_ref[id]) != 0)) {
printk(KERN_ALERT "xennet_tx_buf_gc: warning "
"-- grant still in use by backend "
"domain.\n");
BUG();
}
gnttab_end_foreign_access_ref(
np->grant_tx_ref[id], GNTMAP_readonly);
gnttab_release_grant_reference(
&np->gref_tx_head, np->grant_tx_ref[id]);
np->grant_tx_ref[id] = GRANT_INVALID_REF;
add_id_to_freelist(&np->tx_skb_freelist, np->tx_skbs, id);
dev_kfree_skb_irq(skb);
}
np->tx.rsp_cons = prod;
np->tx.sring->rsp_event =
prod + ((np->tx.sring->req_prod - prod) >> 1) + 1;
mb();
} while ((cons == prod) && (prod != np->tx.sring->rsp_prod));
xennet_maybe_wake_tx(dev);
}
void gnt_exit(void)
{
printk(KERN_DEBUG "\ncleanup grant ref:");
if (gnttab_query_foreign_access(info.gref) == 0) {
printk(KERN_DEBUG "\n xen:No one has mapped this frame");
gnttab_end_foreign_access(info.gref, 0, page);
//gnttab_end_foreign_access(info.gref, 0, sring);
} else {
printk(KERN_DEBUG "\n xen:Someone has mapped this frame");
gnttab_end_foreign_access(info.gref, 0, page);
//gnttab_end_foreign_access(info.gref, 0, sring);
}
remove_proc_entry("file", proc_dir);
remove_proc_entry("demo", NULL);
printk(KERN_DEBUG "...\n...");
}
static void scsifront_gnttab_done(struct vscsifrnt_info *info, uint32_t id)
{
struct vscsifrnt_shadow *s = info->shadow[id];
int i;
if (s->sc->sc_data_direction == DMA_NONE)
return;
for (i = 0; i < s->nr_grants; i++) {
if (unlikely(gnttab_query_foreign_access(s->gref[i]) != 0)) {
shost_printk(KERN_ALERT, info->host, KBUILD_MODNAME
"grant still in use by backend\n");
BUG();
}
gnttab_end_foreign_access(s->gref[i], 0, 0UL);
}
kfree(s->sg);
}
