xsk: remove rebind support

Supporting rebind, i.e. after a successful bind the process can call
bind again without closing the socket, makes the AF_XDP setup state
machine more complex. Constrain the state space, by not supporting
rebind.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Björn Töpel 2018-05-22 09:34:56 +02:00 committed by Daniel Borkmann
parent d849f9f976
commit 959b71db53

View File

@ -227,14 +227,6 @@ static int xsk_init_queue(u32 entries, struct xsk_queue **queue,
return 0;
}
static void __xsk_release(struct xdp_sock *xs)
{
/* Wait for driver to stop using the xdp socket. */
synchronize_net();
dev_put(xs->dev);
}
static int xsk_release(struct socket *sock)
{
struct sock *sk = sock->sk;
@ -251,7 +243,9 @@ static int xsk_release(struct socket *sock)
local_bh_enable();
if (xs->dev) {
__xsk_release(xs);
/* Wait for driver to stop using the xdp socket. */
synchronize_net();
dev_put(xs->dev);
xs->dev = NULL;
}
@ -285,9 +279,8 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
{
struct sockaddr_xdp *sxdp = (struct sockaddr_xdp *)addr;
struct sock *sk = sock->sk;
struct net_device *dev, *dev_curr;
struct xdp_sock *xs = xdp_sk(sk);
struct xdp_umem *old_umem = NULL;
struct net_device *dev;
int err = 0;
if (addr_len < sizeof(struct sockaddr_xdp))
@ -296,7 +289,11 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
return -EINVAL;
mutex_lock(&xs->mutex);
dev_curr = xs->dev;
if (xs->dev) {
err = -EBUSY;
goto out_release;
}
dev = dev_get_by_index(sock_net(sk), sxdp->sxdp_ifindex);
if (!dev) {
err = -ENODEV;
@ -343,7 +340,6 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
}
xdp_get_umem(umem_xs->umem);
old_umem = xs->umem;
xs->umem = umem_xs->umem;
sockfd_put(sock);
} else if (!xs->umem || !xdp_umem_validate_queues(xs->umem)) {
@ -355,14 +351,6 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
xskq_set_umem(xs->umem->cq, &xs->umem->props);
}
/* Rebind? */
if (dev_curr && (dev_curr != dev ||
xs->queue_id != sxdp->sxdp_queue_id)) {
__xsk_release(xs);
if (old_umem)
xdp_put_umem(old_umem);
}
xs->dev = dev;
xs->queue_id = sxdp->sxdp_queue_id;