Signed-off-by: Gerd Hoffmann <kraxel@suse.de>
Index: source-lnx-stable-22813/drivers/xen/netfront/netfront.c
===================================================================
--- source-lnx-stable-22813.orig/drivers/xen/netfront/netfront.c	2006-08-17 15:20:17.000000000 +0200
+++ source-lnx-stable-22813/drivers/xen/netfront/netfront.c	2006-08-17 15:20:17.000000000 +0200
@@ -494,6 +494,7 @@ static int network_open(struct net_devic
 {
 	struct netfront_info *np = netdev_priv(dev);
 
+	DPRINTK("%s\n", np->xbdev->nodename);
 	memset(&np->stats, 0, sizeof(np->stats));
 
 	network_alloc_rx_buffers(dev);
@@ -1285,10 +1286,80 @@ err:
 	return more_to_do;
 }
 
+static void netif_release_rx_bufs(struct netfront_info *np)
+{
+	struct mmu_update      *mmu = np->rx_mmu;
+	struct multicall_entry *mcl = np->rx_mcl;
+	struct sk_buff *skb;
+	unsigned long mfn;
+	int bufs = 0, gnttab = 0, unused = 0;
+	int id, ref;
+
+	spin_lock(&np->rx_lock);
+
+	for (id = 0; id < NET_RX_RING_SIZE; id++) {
+		if ((ref = np->grant_rx_ref[id]) == GRANT_INVALID_REF) {
+			unused++;
+			continue;
+		}
+		if ((mfn = gnttab_end_foreign_transfer_ref(ref)) == 0) {
+			gnttab++;
+			continue;
+		}
+
+		gnttab_release_grant_reference(&np->gref_rx_head, ref);
+		np->grant_rx_ref[id] = GRANT_INVALID_REF;
+
+		skb = np->rx_skbs[id];
+		add_id_to_freelist(np->rx_skbs, id);
+
+		if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+			/* Remap the page. */
+			MULTI_update_va_mapping(mcl, (unsigned long)skb->head,
+						pfn_pte_ma(mfn, PAGE_KERNEL),
+						0);
+			mcl++;
+			mmu->ptr = ((maddr_t)mfn << PAGE_SHIFT)
+				| MMU_MACHPHYS_UPDATE;
+			mmu->val = __pa(skb->head) >> PAGE_SHIFT;
+			mmu++;
+
+			set_phys_to_machine(__pa(skb->head) >> PAGE_SHIFT,
+					    mfn);
+		}
+		bufs++;
+
+#if 0 /* FIXME */
+		dev_kfree_skb(skb);
+#endif
+	}
+
+	printk("%s: %d released ok, %d gnttab errs, %d unused slots\n",
+	       __FUNCTION__, bufs, gnttab, unused);
+	if (0 == bufs)
+		return;
+
+	/* Some pages are no longer absent... */
+	balloon_update_driver_allowance(-bufs);
+
+	if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+		/* Do all the remapping work, and M2P updates, in one big hypercall. */
+		mcl->op = __HYPERVISOR_mmu_update;
+		mcl->args[0] = (unsigned long)np->rx_mmu;
+		mcl->args[1] = mmu - np->rx_mmu;
+		mcl->args[2] = 0;
+		mcl->args[3] = DOMID_SELF;
+		mcl++;
+		HYPERVISOR_multicall(np->rx_mcl, mcl - np->rx_mcl);
+	}
+
+	spin_unlock(&np->rx_lock);
+}
 
 static int network_close(struct net_device *dev)
 {
 	struct netfront_info *np = netdev_priv(dev);
+	DPRINTK("%s\n", np->xbdev->nodename);
 	netif_stop_queue(np->netdev);
 	return 0;
 }
@@ -1427,6 +1498,8 @@ static void network_connect(struct net_d
 static void netif_uninit(struct net_device *dev)
 {
 	struct netfront_info *np = netdev_priv(dev);
+	DPRINTK("%s\n", np->xbdev->nodename);
+	netif_release_rx_bufs(np);
 	gnttab_free_grant_references(np->gref_tx_head);
 	gnttab_free_grant_references(np->gref_rx_head);
 }