bpf: offload: factor out netdev checking at allocation time

Add a helper to check if netdev could be found and whether it
has .ndo_bpf callback.  There is no need to check the callback
every time it's invoked, ndos can't reasonably be swapped for
a set without .ndp_bpf while program is loaded.

bpf_dev_offload_check() will also be used by map offload.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Jakub Kicinski 2018-01-11 20:29:08 -08:00 committed by Daniel Borkmann
parent 0a9c1991f2
commit 5bc2d55c6a
1 changed files with 20 additions and 8 deletions

View File

@ -30,9 +30,19 @@
static DECLARE_RWSEM(bpf_devs_lock);
static LIST_HEAD(bpf_prog_offload_devs);
static int bpf_dev_offload_check(struct net_device *netdev)
{
if (!netdev)
return -EINVAL;
if (!netdev->netdev_ops->ndo_bpf)
return -EOPNOTSUPP;
return 0;
}
int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr)
{
struct bpf_prog_offload *offload;
int err;
if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS &&
attr->prog_type != BPF_PROG_TYPE_XDP)
@ -49,12 +59,15 @@ int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr)
offload->netdev = dev_get_by_index(current->nsproxy->net_ns,
attr->prog_ifindex);
if (!offload->netdev)
goto err_free;
err = bpf_dev_offload_check(offload->netdev);
if (err)
goto err_maybe_put;
down_write(&bpf_devs_lock);
if (offload->netdev->reg_state != NETREG_REGISTERED)
if (offload->netdev->reg_state != NETREG_REGISTERED) {
err = -EINVAL;
goto err_unlock;
}
prog->aux->offload = offload;
list_add_tail(&offload->offloads, &bpf_prog_offload_devs);
dev_put(offload->netdev);
@ -63,10 +76,11 @@ int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr)
return 0;
err_unlock:
up_write(&bpf_devs_lock);
dev_put(offload->netdev);
err_free:
err_maybe_put:
if (offload->netdev)
dev_put(offload->netdev);
kfree(offload);
return -EINVAL;
return err;
}
static int __bpf_offload_ndo(struct bpf_prog *prog, enum bpf_netdev_command cmd,
@ -80,8 +94,6 @@ static int __bpf_offload_ndo(struct bpf_prog *prog, enum bpf_netdev_command cmd,
if (!offload)
return -ENODEV;
netdev = offload->netdev;
if (!netdev->netdev_ops->ndo_bpf)
return -EOPNOTSUPP;
data->command = cmd;