/*
* Remove the service connection from the peer's tree, thereby removing it as a
* target for incoming packets.
*/
void rxrpc_unpublish_service_conn(struct rxrpc_connection *conn)
{
struct rxrpc_peer *peer = conn->params.peer;
write_seqlock_bh(&peer->service_conn_lock);
if (test_and_clear_bit(RXRPC_CONN_IN_SERVICE_CONNS, &conn->flags))
rb_erase(&conn->service_node, &peer->service_conns);
write_sequnlock_bh(&peer->service_conn_lock);
}
/* Update system visible IP port range */
static void set_local_port_range(struct net *net, int range[2])
{
bool same_parity = !((range[0] ^ range[1]) & 1);
write_seqlock_bh(&net->ipv4.ip_local_ports.lock);
if (same_parity && !net->ipv4.ip_local_ports.warned) {
net->ipv4.ip_local_ports.warned = true;
pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
}
net->ipv4.ip_local_ports.range[0] = range[0];
net->ipv4.ip_local_ports.range[1] = range[1];
write_sequnlock_bh(&net->ipv4.ip_local_ports.lock);
}
/*
* Insert a service connection into a peer's tree, thereby making it a target
* for incoming packets.
*/
static void rxrpc_publish_service_conn(struct rxrpc_peer *peer,
struct rxrpc_connection *conn)
{
struct rxrpc_connection *cursor = NULL;
struct rxrpc_conn_proto k = conn->proto;
struct rb_node **pp, *parent;
write_seqlock_bh(&peer->service_conn_lock);
pp = &peer->service_conns.rb_node;
parent = NULL;
while (*pp) {
parent = *pp;
cursor = rb_entry(parent,
struct rxrpc_connection, service_node);
if (cursor->proto.index_key < k.index_key)
pp = &(*pp)->rb_left;
else if (cursor->proto.index_key > k.index_key)
pp = &(*pp)->rb_right;
else
goto found_extant_conn;
}
rb_link_node_rcu(&conn->service_node, parent, pp);
rb_insert_color(&conn->service_node, &peer->service_conns);
conn_published:
set_bit(RXRPC_CONN_IN_SERVICE_CONNS, &conn->flags);
write_sequnlock_bh(&peer->service_conn_lock);
_leave(" = %d [new]", conn->debug_id);
return;
found_extant_conn:
if (atomic_read(&cursor->usage) == 0)
goto replace_old_connection;
write_sequnlock_bh(&peer->service_conn_lock);
/* We should not be able to get here. rxrpc_incoming_connection() is
* called in a non-reentrant context, so there can't be a race to
* insert a new connection.
*/
BUG();
replace_old_connection:
/* The old connection is from an outdated epoch. */
_debug("replace conn");
rb_replace_node_rcu(&cursor->service_node,
&conn->service_node,
&peer->service_conns);
clear_bit(RXRPC_CONN_IN_SERVICE_CONNS, &cursor->flags);
goto conn_published;
}
/* Stolen from ip_finish_output2
* PRE : skb->dev is set to the device we are leaving by
* skb->dst is not NULL
* POST: the packet is sent with the link layer header pushed
* the packet is destroyed
*/
static void ip_direct_send(struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
struct hh_cache *hh = dst->hh;
struct net_device *dev = dst->dev;
int hh_len = LL_RESERVED_SPACE(dev);
/* Be paranoid, rather than too clever. */
if (unlikely(skb_headroom(skb) < hh_len )) {
struct sk_buff *skb2;
skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
if (skb2 == NULL) {
kfree_skb(skb);
return;
}
if (skb->sk)
skb_set_owner_w(skb2, skb->sk);
kfree_skb(skb);
skb = skb2;
}
if (hh) {
int hh_alen;
write_seqlock_bh(&hh->hh_lock);
hh_alen = HH_DATA_ALIGN(hh->hh_len);
memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
write_sequnlock_bh(&hh->hh_lock);
skb_push(skb, hh->hh_len);
hh->hh_output(skb);
} else if (dst->neighbour)
dst->neighbour->output(skb);
else {
if (net_ratelimit())
pr_debug(KERN_DEBUG "ipt_ROUTE: no hdr & no neighbour cache!\n");
kfree_skb(skb);
}
}
/*
* Must not be called with IRQs off. This should only be used on the
* slow path.
*
* Copy a foreign granted page to local memory.
*/
int gnttab_copy_grant_page(grant_ref_t ref, struct page **pagep)
{
struct gnttab_unmap_and_replace unmap;
mmu_update_t mmu;
struct page *page;
struct page *new_page;
void *new_addr;
void *addr;
paddr_t pfn;
maddr_t mfn;
maddr_t new_mfn;
int err;
page = *pagep;
if (!get_page_unless_zero(page))
return -ENOENT;
err = -ENOMEM;
new_page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
if (!new_page)
goto out;
new_addr = page_address(new_page);
addr = page_address(page);
copy_page(new_addr, addr);
pfn = page_to_pfn(page);
mfn = pfn_to_mfn(pfn);
new_mfn = virt_to_mfn(new_addr);
write_seqlock_bh(&gnttab_dma_lock);
/* Make seq visible before checking page_mapped. */
smp_mb();
/* Has the page been DMA-mapped? */
if (unlikely(page_mapped(page))) {
write_sequnlock_bh(&gnttab_dma_lock);
put_page(new_page);
err = -EBUSY;
goto out;
}
if (!xen_feature(XENFEAT_auto_translated_physmap))
set_phys_to_machine(pfn, new_mfn);
gnttab_set_replace_op(&unmap, (unsigned long)addr,
(unsigned long)new_addr, ref);
err = HYPERVISOR_grant_table_op(GNTTABOP_unmap_and_replace,
&unmap, 1);
BUG_ON(err);
BUG_ON(unmap.status != GNTST_okay);
write_sequnlock_bh(&gnttab_dma_lock);
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
set_phys_to_machine(page_to_pfn(new_page), INVALID_P2M_ENTRY);
mmu.ptr = (new_mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE;
mmu.val = pfn;
err = HYPERVISOR_mmu_update(&mmu, 1, NULL, DOMID_SELF);
BUG_ON(err);
}
new_page->mapping = page->mapping;
new_page->index = page->index;
set_bit(PG_foreign, &new_page->flags);
if (PageReserved(page))
SetPageReserved(new_page);
*pagep = new_page;
SetPageForeign(page, gnttab_page_free);
page->mapping = NULL;
out:
put_page(page);
return err;
}