diff options
| author | Jeff Moyer <jmoyer@redhat.com> | 2005-06-22 22:05:59 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2005-06-22 22:05:59 -0700 |
| commit | fbeec2e1552949002065435c9829dc244ad85407 (patch) | |
| tree | d97dc663bbef4bf59a1858b23a327f14043c33d1 /net | |
| parent | 115c1d6e61b70851d9a363328c3b8d4c2559a1d3 (diff) | |
| download | linux-fbeec2e1552949002065435c9829dc244ad85407.tar.gz | |
[NETPOLL]: allow multiple netpoll_clients to register against one interface
This patch provides support for registering multiple netpoll clients to the same network device. Only one of these clients may register an rx_hook, however. In practice, this restriction has not been problematic. It is worth mentioning, though, that the current design can be easily extended to allow for the registration of multiple rx_hooks. The basic idea of the patch is that the rx_np pointer in the netpoll_info structure points to the struct netpoll that has rx_hook filled in. Aside from this one case, there is no need for a pointer from the struct net_device to an individual struct netpoll. A lock is introduced to protect the setting and clearing of the np_rx pointer. The pointer will only be cleared upon netpoll client module removal, and the lock should be uncontested. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/netpoll.c | 39 |
1 files changed, 29 insertions, 10 deletions
diff --git a/net/core/netpoll.c b/net/core/netpoll.c index ab3c0c9713b0..c327c9edadc5 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -349,11 +349,15 @@ static void arp_reply(struct sk_buff *skb) unsigned char *arp_ptr; int size, type = ARPOP_REPLY, ptype = ETH_P_ARP; u32 sip, tip; + unsigned long flags; struct sk_buff *send_skb; struct netpoll *np = NULL; - if (npinfo) - np = npinfo->np; + spin_lock_irqsave(&npinfo->rx_lock, flags); + if (npinfo->rx_np && npinfo->rx_np->dev == skb->dev) + np = npinfo->rx_np; + spin_unlock_irqrestore(&npinfo->rx_lock, flags); + if (!np) return; @@ -436,9 +440,9 @@ int __netpoll_rx(struct sk_buff *skb) int proto, len, ulen; struct iphdr *iph; struct udphdr *uh; - struct netpoll *np = skb->dev->npinfo->np; + struct netpoll *np = skb->dev->npinfo->rx_np; - if (!np->rx_hook) + if (!np) goto out; if (skb->dev->type != ARPHRD_ETHER) goto out; @@ -619,6 +623,7 @@ int netpoll_setup(struct netpoll *np) struct net_device *ndev = NULL; struct in_device *in_dev; struct netpoll_info *npinfo; + unsigned long flags; if (np->dev_name) ndev = dev_get_by_name(np->dev_name); @@ -634,9 +639,10 @@ int netpoll_setup(struct netpoll *np) if (!npinfo) goto release; - npinfo->np = NULL; + npinfo->rx_np = NULL; npinfo->poll_lock = SPIN_LOCK_UNLOCKED; npinfo->poll_owner = -1; + npinfo->rx_lock = SPIN_LOCK_UNLOCKED; } else npinfo = ndev->npinfo; @@ -706,9 +712,13 @@ int netpoll_setup(struct netpoll *np) np->name, HIPQUAD(np->local_ip)); } - if(np->rx_hook) - npinfo->rx_flags = NETPOLL_RX_ENABLED; - npinfo->np = np; + if (np->rx_hook) { + spin_lock_irqsave(&npinfo->rx_lock, flags); + npinfo->rx_flags |= NETPOLL_RX_ENABLED; + npinfo->rx_np = np; + spin_unlock_irqrestore(&npinfo->rx_lock, flags); + } + /* last thing to do is link it to the net device structure */ ndev->npinfo = npinfo; return 0; @@ -723,11 +733,20 @@ int netpoll_setup(struct netpoll *np) void netpoll_cleanup(struct netpoll *np) { + struct netpoll_info *npinfo; + unsigned long flags; + if (np->dev) { - if (np->dev->npinfo) - np->dev->npinfo->np = NULL; + npinfo = np->dev->npinfo; + if (npinfo && npinfo->rx_np == np) { + spin_lock_irqsave(&npinfo->rx_lock, flags); + npinfo->rx_np = NULL; + npinfo->rx_flags &= ~NETPOLL_RX_ENABLED; + spin_unlock_irqrestore(&npinfo->rx_lock, flags); + } dev_put(np->dev); } + np->dev = NULL; } |