AT91RM9200 Ethernet: Support additional PHYs
[powerpc.git] / drivers / net / pppoe.c
index ebfa296..6f98834 100644 (file)
@@ -207,7 +207,7 @@ static inline struct pppox_sock *get_item(unsigned long sid,
 
 static inline struct pppox_sock *get_item_by_addr(struct sockaddr_pppox *sp)
 {
-       struct net_device *dev = NULL;
+       struct net_device *dev;
        int ifindex;
 
        dev = dev_get_by_name(sp->sa_addr.pppoe.dev);
@@ -218,20 +218,6 @@ static inline struct pppox_sock *get_item_by_addr(struct sockaddr_pppox *sp)
        return get_item(sp->sa_addr.pppoe.sid, sp->sa_addr.pppoe.remote, ifindex);
 }
 
-static inline int set_item(struct pppox_sock *po)
-{
-       int i;
-
-       if (!po)
-               return -EINVAL;
-
-       write_lock_bh(&pppoe_hash_lock);
-       i = __set_item(po);
-       write_unlock_bh(&pppoe_hash_lock);
-
-       return i;
-}
-
 static inline struct pppox_sock *delete_item(unsigned long sid, char *addr, int ifindex)
 {
        struct pppox_sock *ret;
@@ -255,54 +241,53 @@ static inline struct pppox_sock *delete_item(unsigned long sid, char *addr, int
 static void pppoe_flush_dev(struct net_device *dev)
 {
        int hash;
-
        BUG_ON(dev == NULL);
 
-       read_lock_bh(&pppoe_hash_lock);
+       write_lock_bh(&pppoe_hash_lock);
        for (hash = 0; hash < PPPOE_HASH_SIZE; hash++) {
                struct pppox_sock *po = item_hash_table[hash];
 
                while (po != NULL) {
-                       if (po->pppoe_dev == dev) {
-                               struct sock *sk = sk_pppox(po);
-
-                               sock_hold(sk);
-                               po->pppoe_dev = NULL;
+                       struct sock *sk = sk_pppox(po);
+                       if (po->pppoe_dev != dev) {
+                               po = po->next;
+                               continue;
+                       }
+                       po->pppoe_dev = NULL;
+                       dev_put(dev);
 
-                               /* We hold a reference to SK, now drop the
-                                * hash table lock so that we may attempt
-                                * to lock the socket (which can sleep).
-                                */
-                               read_unlock_bh(&pppoe_hash_lock);
 
-                               lock_sock(sk);
+                       /* We always grab the socket lock, followed by the
+                        * pppoe_hash_lock, in that order.  Since we should
+                        * hold the sock lock while doing any unbinding,
+                        * we need to release the lock we're holding.
+                        * Hold a reference to the sock so it doesn't disappear
+                        * as we're jumping between locks.
+                        */
 
-                               if (sk->sk_state &
-                                   (PPPOX_CONNECTED | PPPOX_BOUND)) {
-                                       pppox_unbind_sock(sk);
-                                       dev_put(dev);
-                                       sk->sk_state = PPPOX_ZOMBIE;
-                                       sk->sk_state_change(sk);
-                               }
+                       sock_hold(sk);
 
-                               release_sock(sk);
+                       write_unlock_bh(&pppoe_hash_lock);
+                       lock_sock(sk);
 
-                               sock_put(sk);
+                       if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
+                               pppox_unbind_sock(sk);
+                               sk->sk_state = PPPOX_ZOMBIE;
+                               sk->sk_state_change(sk);
+                       }
 
-                               read_lock_bh(&pppoe_hash_lock);
+                       release_sock(sk);
+                       sock_put(sk);
 
-                               /* Now restart from the beginning of this
-                                * hash chain.  We always NULL out pppoe_dev
-                                * so we are guaranteed to make forward
-                                * progress.
-                                */
-                               po = item_hash_table[hash];
-                               continue;
-                       }
-                       po = po->next;
+                       /* Restart scan at the beginning of this hash chain.
+                        * While the lock was dropped the chain contents may
+                        * have changed.
+                        */
+                       write_lock_bh(&pppoe_hash_lock);
+                       po = item_hash_table[hash];
                }
        }
-       read_unlock_bh(&pppoe_hash_lock);
+       write_unlock_bh(&pppoe_hash_lock);
 }
 
 static int pppoe_device_event(struct notifier_block *this,
@@ -344,10 +329,10 @@ static struct notifier_block pppoe_notifier = {
 static int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
 {
        struct pppox_sock *po = pppox_sk(sk);
-       struct pppox_sock *relay_po = NULL;
+       struct pppox_sock *relay_po;
 
        if (sk->sk_state & PPPOX_BOUND) {
-               struct pppoe_hdr *ph = (struct pppoe_hdr *) skb->nh.raw;
+               struct pppoe_hdr *ph = pppoe_hdr(skb);
                int len = ntohs(ph->length);
                skb_pull_rcsum(skb, sizeof(struct pppoe_hdr));
                if (pskb_trim_rcsum(skb, len))
@@ -401,7 +386,7 @@ static int pppoe_rcv(struct sk_buff *skb,
        if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
                goto out;
 
-       ph = (struct pppoe_hdr *) skb->nh.raw;
+       ph = pppoe_hdr(skb);
 
        po = get_item((unsigned long) ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
        if (po != NULL)
@@ -433,7 +418,7 @@ static int pppoe_disc_rcv(struct sk_buff *skb,
        if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
                goto out;
 
-       ph = (struct pppoe_hdr *) skb->nh.raw;
+       ph = pppoe_hdr(skb);
        if (ph->code != PADT_CODE)
                goto abort;
 
@@ -514,36 +499,49 @@ static int pppoe_release(struct socket *sock)
 {
        struct sock *sk = sock->sk;
        struct pppox_sock *po;
-       int error = 0;
 
        if (!sk)
                return 0;
 
-       if (sock_flag(sk, SOCK_DEAD))
+       lock_sock(sk);
+       if (sock_flag(sk, SOCK_DEAD)){
+               release_sock(sk);
                return -EBADF;
+       }
 
        pppox_unbind_sock(sk);
 
        /* Signal the death of the socket. */
        sk->sk_state = PPPOX_DEAD;
 
+
+       /* Write lock on hash lock protects the entire "po" struct from
+        * concurrent updates via pppoe_flush_dev. The "po" struct should
+        * be considered part of the hash table contents, thus protected
+        * by the hash table lock */
+       write_lock_bh(&pppoe_hash_lock);
+
        po = pppox_sk(sk);
        if (po->pppoe_pa.sid) {
-               delete_item(po->pppoe_pa.sid, po->pppoe_pa.remote, po->pppoe_ifindex);
+               __delete_item(po->pppoe_pa.sid,
+                             po->pppoe_pa.remote, po->pppoe_ifindex);
        }
 
-       if (po->pppoe_dev)
+       if (po->pppoe_dev) {
                dev_put(po->pppoe_dev);
+               po->pppoe_dev = NULL;
+       }
 
-       po->pppoe_dev = NULL;
+       write_unlock_bh(&pppoe_hash_lock);
 
        sock_orphan(sk);
        sock->sk = NULL;
 
        skb_queue_purge(&sk->sk_receive_queue);
+       release_sock(sk);
        sock_put(sk);
 
-       return error;
+       return 0;
 }
 
 
@@ -599,14 +597,18 @@ static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
                po->pppoe_dev = dev;
                po->pppoe_ifindex = dev->ifindex;
 
-               if (!(dev->flags & IFF_UP))
+               write_lock_bh(&pppoe_hash_lock);
+               if (!(dev->flags & IFF_UP)){
+                       write_unlock_bh(&pppoe_hash_lock);
                        goto err_put;
+               }
 
                memcpy(&po->pppoe_pa,
                       &sp->sa_addr.pppoe,
                       sizeof(struct pppoe_addr));
 
-               error = set_item(po);
+               error = __set_item(po);
+               write_unlock_bh(&pppoe_hash_lock);
                if (error < 0)
                        goto err_put;
 
@@ -762,10 +764,10 @@ static int pppoe_ioctl(struct socket *sock, unsigned int cmd,
 static int pppoe_sendmsg(struct kiocb *iocb, struct socket *sock,
                  struct msghdr *m, size_t total_len)
 {
-       struct sk_buff *skb = NULL;
+       struct sk_buff *skb;
        struct sock *sk = sock->sk;
        struct pppox_sock *po = pppox_sk(sk);
-       int error = 0;
+       int error;
        struct pppoe_hdr hdr;
        struct pppoe_hdr *ph;
        struct net_device *dev;
@@ -799,7 +801,7 @@ static int pppoe_sendmsg(struct kiocb *iocb, struct socket *sock,
 
        /* Reserve space for headers. */
        skb_reserve(skb, dev->hard_header_len);
-       skb->nh.raw = skb->data;
+       skb_reset_network_header(skb);
 
        skb->dev = dev;
 
@@ -869,7 +871,8 @@ static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
                        goto abort;
 
                skb_reserve(skb2, dev->hard_header_len + sizeof(struct pppoe_hdr));
-               memcpy(skb_put(skb2, skb->len), skb->data, skb->len);
+               skb_copy_from_linear_data(skb, skb_put(skb2, skb->len),
+                                         skb->len);
        } else {
                /* Make a clone so as to not disturb the original skb,
                 * give dev_queue_xmit something it can free.
@@ -884,7 +887,7 @@ static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
        memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
        skb2->protocol = __constant_htons(ETH_P_PPP_SES);
 
-       skb2->nh.raw = skb2->data;
+       skb_reset_network_header(skb2);
 
        skb2->dev = dev;
 
@@ -929,10 +932,8 @@ static int pppoe_recvmsg(struct kiocb *iocb, struct socket *sock,
                  struct msghdr *m, size_t total_len, int flags)
 {
        struct sock *sk = sock->sk;
-       struct sk_buff *skb = NULL;
+       struct sk_buff *skb;
        int error = 0;
-       int len;
-       struct pppoe_hdr *ph = NULL;
 
        if (sk->sk_state & PPPOX_BOUND) {
                error = -EIO;
@@ -942,26 +943,21 @@ static int pppoe_recvmsg(struct kiocb *iocb, struct socket *sock,
        skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
                                flags & MSG_DONTWAIT, &error);
 
-       if (error < 0) {
+       if (error < 0)
                goto end;
-       }
 
        m->msg_namelen = 0;
 
        if (skb) {
-               error = 0;
-               ph = (struct pppoe_hdr *) skb->nh.raw;
-               len = ntohs(ph->length);
+               struct pppoe_hdr *ph = pppoe_hdr(skb);
+               const int len = ntohs(ph->length);
 
                error = memcpy_toiovec(m->msg_iov, (unsigned char *) &ph->tag[0], len);
-               if (error < 0)
-                       goto do_skb_free;
-               error = len;
+               if (error == 0)
+                       error = len;
        }
 
-do_skb_free:
-       if (skb)
-               kfree_skb(skb);
+       kfree_skb(skb);
 end:
        return error;
 }
@@ -991,7 +987,7 @@ out:
 
 static __inline__ struct pppox_sock *pppoe_get_idx(loff_t pos)
 {
-       struct pppox_sock *po = NULL;
+       struct pppox_sock *po;
        int i = 0;
 
        for (; i < PPPOE_HASH_SIZE; i++) {