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net/appletalk: push down BKL into a atalk_dgram_ops
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Making the BKL usage explicit in appletalk makes it more
obvious where it is used, reduces code size and helps
getting rid of the BKL in common code.

I did not analyse how to kill lock_kernel from appletalk
entirely, this will involve either proving that it's not
needed, or replacing with a proper mutex or spinlock,
after finding out which data structures are protected
by the lock.

Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: [email protected]
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
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@arndb @davem330
arndb authored and davem330 committed Nov 7, 2009
1 parent c6060be commit ecced8b
Showing 1 changed file with 77 additions and 28 deletions.
105 changes: 77 additions & 28 deletions net/appletalk/ddp.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1055,11 +1055,13 @@ static int atalk_release(struct socket *sock)
{
struct sock *sk = sock->sk;

lock_kernel();
if (sk) {
sock_orphan(sk);
sock->sk = NULL;
atalk_destroy_socket(sk);
}
unlock_kernel();
return 0;
}

Expand Down Expand Up @@ -1135,6 +1137,7 @@ static int atalk_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
struct sockaddr_at *addr = (struct sockaddr_at *)uaddr;
struct sock *sk = sock->sk;
struct atalk_sock *at = at_sk(sk);
int err;

if (!sock_flag(sk, SOCK_ZAPPED) ||
addr_len != sizeof(struct sockaddr_at))
Expand All @@ -1143,37 +1146,44 @@ static int atalk_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
if (addr->sat_family != AF_APPLETALK)
return -EAFNOSUPPORT;

lock_kernel();
if (addr->sat_addr.s_net == htons(ATADDR_ANYNET)) {
struct atalk_addr *ap = atalk_find_primary();

err = -EADDRNOTAVAIL;
if (!ap)
return -EADDRNOTAVAIL;
goto out;

at->src_net = addr->sat_addr.s_net = ap->s_net;
at->src_node = addr->sat_addr.s_node= ap->s_node;
} else {
err = -EADDRNOTAVAIL;
if (!atalk_find_interface(addr->sat_addr.s_net,
addr->sat_addr.s_node))
return -EADDRNOTAVAIL;
goto out;

at->src_net = addr->sat_addr.s_net;
at->src_node = addr->sat_addr.s_node;
}

if (addr->sat_port == ATADDR_ANYPORT) {
int n = atalk_pick_and_bind_port(sk, addr);
err = atalk_pick_and_bind_port(sk, addr);

if (n < 0)
return n;
if (err < 0)
goto out;
} else {
at->src_port = addr->sat_port;

err = -EADDRINUSE;
if (atalk_find_or_insert_socket(sk, addr))
return -EADDRINUSE;
goto out;
}

sock_reset_flag(sk, SOCK_ZAPPED);
return 0;
err = 0;
out:
unlock_kernel();
return err;
}

/* Set the address we talk to */
Expand All @@ -1183,6 +1193,7 @@ static int atalk_connect(struct socket *sock, struct sockaddr *uaddr,
struct sock *sk = sock->sk;
struct atalk_sock *at = at_sk(sk);
struct sockaddr_at *addr;
int err;

sk->sk_state = TCP_CLOSE;
sock->state = SS_UNCONNECTED;
Expand All @@ -1207,20 +1218,26 @@ static int atalk_connect(struct socket *sock, struct sockaddr *uaddr,
#endif
}

lock_kernel();
err = -EBUSY;
if (sock_flag(sk, SOCK_ZAPPED))
if (atalk_autobind(sk) < 0)
return -EBUSY;
goto out;

err = -ENETUNREACH;
if (!atrtr_get_dev(&addr->sat_addr))
return -ENETUNREACH;
goto out;

at->dest_port = addr->sat_port;
at->dest_net = addr->sat_addr.s_net;
at->dest_node = addr->sat_addr.s_node;

sock->state = SS_CONNECTED;
sk->sk_state = TCP_ESTABLISHED;
return 0;
err = 0;
out:
unlock_kernel();
return err;
}

/*
Expand All @@ -1233,17 +1250,21 @@ static int atalk_getname(struct socket *sock, struct sockaddr *uaddr,
struct sockaddr_at sat;
struct sock *sk = sock->sk;
struct atalk_sock *at = at_sk(sk);
int err;

lock_kernel();
err = -ENOBUFS;
if (sock_flag(sk, SOCK_ZAPPED))
if (atalk_autobind(sk) < 0)
return -ENOBUFS;
goto out;

*uaddr_len = sizeof(struct sockaddr_at);
memset(&sat.sat_zero, 0, sizeof(sat.sat_zero));

if (peer) {
err = -ENOTCONN;
if (sk->sk_state != TCP_ESTABLISHED)
return -ENOTCONN;
goto out;

sat.sat_addr.s_net = at->dest_net;
sat.sat_addr.s_node = at->dest_node;
Expand All @@ -1254,9 +1275,23 @@ static int atalk_getname(struct socket *sock, struct sockaddr *uaddr,
sat.sat_port = at->src_port;
}

err = 0;
sat.sat_family = AF_APPLETALK;
memcpy(uaddr, &sat, sizeof(sat));
return 0;

out:
unlock_kernel();
return err;
}

static unsigned int atalk_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
int err;
lock_kernel();
err = datagram_poll(file, sock, wait);
unlock_kernel();
return err;
}

#if defined(CONFIG_IPDDP) || defined(CONFIG_IPDDP_MODULE)
Expand Down Expand Up @@ -1564,23 +1599,28 @@ static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
if (len > DDP_MAXSZ)
return -EMSGSIZE;

lock_kernel();
if (usat) {
err = -EBUSY;
if (sock_flag(sk, SOCK_ZAPPED))
if (atalk_autobind(sk) < 0)
return -EBUSY;
goto out;

err = -EINVAL;
if (msg->msg_namelen < sizeof(*usat) ||
usat->sat_family != AF_APPLETALK)
return -EINVAL;
goto out;

err = -EPERM;
/* netatalk didn't implement this check */
if (usat->sat_addr.s_node == ATADDR_BCAST &&
!sock_flag(sk, SOCK_BROADCAST)) {
return -EPERM;
goto out;
}
} else {
err = -ENOTCONN;
if (sk->sk_state != TCP_ESTABLISHED)
return -ENOTCONN;
goto out;
usat = &local_satalk;
usat->sat_family = AF_APPLETALK;
usat->sat_port = at->dest_port;
Expand All @@ -1604,8 +1644,9 @@ static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr

rt = atrtr_find(&at_hint);
}
err = ENETUNREACH;
if (!rt)
return -ENETUNREACH;
goto out;

dev = rt->dev;

Expand All @@ -1615,7 +1656,7 @@ static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
size += dev->hard_header_len;
skb = sock_alloc_send_skb(sk, size, (flags & MSG_DONTWAIT), &err);
if (!skb)
return err;
goto out;

skb->sk = sk;
skb_reserve(skb, ddp_dl->header_length);
Expand All @@ -1638,7 +1679,8 @@ static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
if (err) {
kfree_skb(skb);
return -EFAULT;
err = -EFAULT;
goto out;
}

if (sk->sk_no_check == 1)
Expand Down Expand Up @@ -1677,7 +1719,8 @@ static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
rt = atrtr_find(&at_lo);
if (!rt) {
kfree_skb(skb);
return -ENETUNREACH;
err = -ENETUNREACH;
goto out;
}
dev = rt->dev;
skb->dev = dev;
Expand All @@ -1697,7 +1740,9 @@ static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
}
SOCK_DEBUG(sk, "SK %p: Done write (%Zd).\n", sk, len);

return len;
out:
unlock_kernel();
return err ? : len;
}

static int atalk_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
Expand All @@ -1709,10 +1754,13 @@ static int atalk_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
int copied = 0;
int offset = 0;
int err = 0;
struct sk_buff *skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
struct sk_buff *skb;

lock_kernel();
skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
flags & MSG_DONTWAIT, &err);
if (!skb)
return err;
goto out;

/* FIXME: use skb->cb to be able to use shared skbs */
ddp = ddp_hdr(skb);
Expand Down Expand Up @@ -1740,6 +1788,9 @@ static int atalk_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
}

skb_free_datagram(sk, skb); /* Free the datagram. */

out:
unlock_kernel();
return err ? : copied;
}

Expand Down Expand Up @@ -1830,7 +1881,7 @@ static const struct net_proto_family atalk_family_ops = {
.owner = THIS_MODULE,
};

static const struct proto_ops SOCKOPS_WRAPPED(atalk_dgram_ops) = {
static const struct proto_ops atalk_dgram_ops = {
.family = PF_APPLETALK,
.owner = THIS_MODULE,
.release = atalk_release,
Expand All @@ -1839,7 +1890,7 @@ static const struct proto_ops SOCKOPS_WRAPPED(atalk_dgram_ops) = {
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = atalk_getname,
.poll = datagram_poll,
.poll = atalk_poll,
.ioctl = atalk_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = atalk_compat_ioctl,
Expand All @@ -1854,8 +1905,6 @@ static const struct proto_ops SOCKOPS_WRAPPED(atalk_dgram_ops) = {
.sendpage = sock_no_sendpage,
};

SOCKOPS_WRAP(atalk_dgram, PF_APPLETALK);

static struct notifier_block ddp_notifier = {
.notifier_call = ddp_device_event,
};
Expand Down

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