diff options
| -rw-r--r-- | drivers/net/ppp/ppp_generic.c | 38 |
1 files changed, 29 insertions, 9 deletions
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 4cf9d1822a83..8c98cbd4b06d 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -107,6 +107,11 @@ struct ppp_file { #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp) #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel) +struct ppp_xmit_recursion { + struct task_struct *owner; + local_lock_t bh_lock; +}; + /* * Data structure describing one ppp unit. * A ppp unit corresponds to a ppp network interface device @@ -120,7 +125,7 @@ struct ppp { int n_channels; /* how many channels are attached 54 */ spinlock_t rlock; /* lock for receive side 58 */ spinlock_t wlock; /* lock for transmit side 5c */ - int __percpu *xmit_recursion; /* xmit recursion detect */ + struct ppp_xmit_recursion __percpu *xmit_recursion; /* xmit recursion detect */ int mru; /* max receive unit 60 */ unsigned int flags; /* control bits 64 */ unsigned int xstate; /* transmit state bits 68 */ @@ -1249,13 +1254,18 @@ static int ppp_dev_configure(struct net *src_net, struct net_device *dev, spin_lock_init(&ppp->rlock); spin_lock_init(&ppp->wlock); - ppp->xmit_recursion = alloc_percpu(int); + ppp->xmit_recursion = alloc_percpu(struct ppp_xmit_recursion); if (!ppp->xmit_recursion) { err = -ENOMEM; goto err1; } - for_each_possible_cpu(cpu) - (*per_cpu_ptr(ppp->xmit_recursion, cpu)) = 0; + for_each_possible_cpu(cpu) { + struct ppp_xmit_recursion *xmit_recursion; + + xmit_recursion = per_cpu_ptr(ppp->xmit_recursion, cpu); + xmit_recursion->owner = NULL; + local_lock_init(&xmit_recursion->bh_lock); + } #ifdef CONFIG_PPP_MULTILINK ppp->minseq = -1; @@ -1660,15 +1670,20 @@ static void __ppp_xmit_process(struct ppp *ppp, struct sk_buff *skb) static void ppp_xmit_process(struct ppp *ppp, struct sk_buff *skb) { + struct ppp_xmit_recursion *xmit_recursion; + local_bh_disable(); - if (unlikely(*this_cpu_ptr(ppp->xmit_recursion))) + xmit_recursion = this_cpu_ptr(ppp->xmit_recursion); + if (xmit_recursion->owner == current) goto err; + local_lock_nested_bh(&ppp->xmit_recursion->bh_lock); + xmit_recursion->owner = current; - (*this_cpu_ptr(ppp->xmit_recursion))++; __ppp_xmit_process(ppp, skb); - (*this_cpu_ptr(ppp->xmit_recursion))--; + xmit_recursion->owner = NULL; + local_unlock_nested_bh(&ppp->xmit_recursion->bh_lock); local_bh_enable(); return; @@ -2169,11 +2184,16 @@ static void __ppp_channel_push(struct channel *pch) static void ppp_channel_push(struct channel *pch) { + struct ppp_xmit_recursion *xmit_recursion; + read_lock_bh(&pch->upl); if (pch->ppp) { - (*this_cpu_ptr(pch->ppp->xmit_recursion))++; + xmit_recursion = this_cpu_ptr(pch->ppp->xmit_recursion); + local_lock_nested_bh(&pch->ppp->xmit_recursion->bh_lock); + xmit_recursion->owner = current; __ppp_channel_push(pch); - (*this_cpu_ptr(pch->ppp->xmit_recursion))--; + xmit_recursion->owner = NULL; + local_unlock_nested_bh(&pch->ppp->xmit_recursion->bh_lock); } else { __ppp_channel_push(pch); } |