[SCTP]: Rewrite of sctp buffer management code

[linux-2.6-omap-h63xx.git] / net / sctp / socket.c

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 772fbfb4bfda801e63229c4ac6479278e823459c..b9952425c79ae398ebd6aef9ee9a28cce587ba69 100644 (file)
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -107,23 +107,42 @@ static void sctp_sock_migrate(struct sock *, struct sock *,
                              struct sctp_association *, sctp_socket_type_t);
 static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG;
 
+extern struct kmem_cache *sctp_bucket_cachep;
+extern int sysctl_sctp_mem[3];
+extern int sysctl_sctp_rmem[3];
+extern int sysctl_sctp_wmem[3];
+
+int sctp_memory_pressure;
+atomic_t sctp_memory_allocated;
+atomic_t sctp_sockets_allocated;
+
+static void sctp_enter_memory_pressure(void)
+{
+       sctp_memory_pressure = 1;
+}
+
+
 /* Get the sndbuf space available at the time on the association.  */
 static inline int sctp_wspace(struct sctp_association *asoc)
 {
-       struct sock *sk = asoc->base.sk;
-       int amt = 0;
+       int amt;
 
-       if (asoc->ep->sndbuf_policy) {
-               /* make sure that no association uses more than sk_sndbuf */
-               amt = sk->sk_sndbuf - asoc->sndbuf_used;
+       if (asoc->ep->sndbuf_policy)
+               amt = asoc->sndbuf_used;
+       else
+               amt = atomic_read(&asoc->base.sk->sk_wmem_alloc);
+
+       if (amt >= asoc->base.sk->sk_sndbuf) {
+               if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
+                       amt = 0;
+               else {
+                       amt = sk_stream_wspace(asoc->base.sk);
+                       if (amt < 0)
+                               amt = 0;
+               }
        } else {
-               /* do socket level accounting */
-               amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
+               amt = asoc->base.sk->sk_sndbuf - amt;
        }
-
-       if (amt < 0)
-               amt = 0;
-
        return amt;
 }
 
@@ -155,6 +174,7 @@ static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
                                sizeof(struct sctp_chunk);
 
        atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
+       sk_charge_skb(sk, chunk->skb);
 }
 
 /* Verify that this is a valid address. */
@@ -3293,6 +3313,7 @@ SCTP_STATIC int sctp_init_sock(struct sock *sk)
        sp->hmac = NULL;
 
        SCTP_DBG_OBJCNT_INC(sock);
+       atomic_inc(&sctp_sockets_allocated);
        return 0;
 }
 
@@ -3306,7 +3327,7 @@ SCTP_STATIC int sctp_destroy_sock(struct sock *sk)
        /* Release our hold on the endpoint. */
        ep = sctp_sk(sk)->ep;
        sctp_endpoint_free(ep);
-
+       atomic_dec(&sctp_sockets_allocated);
        return 0;
 }
 
@@ -5720,6 +5741,12 @@ static void sctp_wfree(struct sk_buff *skb)
 
        atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
 
+       /*
+        * This undoes what is done via sk_charge_skb
+        */
+       sk->sk_wmem_queued   -= skb->truesize;
+       sk->sk_forward_alloc += skb->truesize;
+
        sock_wfree(skb);
        __sctp_write_space(asoc);
 
@@ -5737,6 +5764,11 @@ void sctp_sock_rfree(struct sk_buff *skb)
        struct sctp_ulpevent *event = sctp_skb2event(skb);
 
        atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
+
+       /*
+        * Mimic the behavior of sk_stream_rfree
+        */
+       sk->sk_forward_alloc += event->rmem_len;
 }
 
 
@@ -6126,6 +6158,7 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
        sctp_release_sock(newsk);
 }
 
+
 /* This proto struct describes the ULP interface for SCTP.  */
 struct proto sctp_prot = {
        .name        =  "SCTP",
@@ -6148,6 +6181,12 @@ struct proto sctp_prot = {
        .unhash      =  sctp_unhash,
        .get_port    =  sctp_get_port,
        .obj_size    =  sizeof(struct sctp_sock),
+       .sysctl_mem  =  sysctl_sctp_mem,
+       .sysctl_rmem =  sysctl_sctp_rmem,
+       .sysctl_wmem =  sysctl_sctp_wmem,
+       .memory_pressure = &sctp_memory_pressure,
+       .enter_memory_pressure = sctp_enter_memory_pressure,
+       .memory_allocated = &sctp_memory_allocated,
 };
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
@@ -6172,5 +6211,11 @@ struct proto sctpv6_prot = {
        .unhash         = sctp_unhash,
        .get_port       = sctp_get_port,
        .obj_size       = sizeof(struct sctp6_sock),
+       .sysctl_mem     = sysctl_sctp_mem,
+       .sysctl_rmem    = sysctl_sctp_rmem,
+       .sysctl_wmem    = sysctl_sctp_wmem,
+       .memory_pressure = &sctp_memory_pressure,
+       .enter_memory_pressure = sctp_enter_memory_pressure,
+       .memory_allocated = &sctp_memory_allocated,
 };
 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */