- Conditionally pickup Giant around the network interface

  ioctl routines if we are running with !mpsafenet
- Change un-conditional Giant acquisition around ifpromisc
  to occur only if we are running with !mpsafenet

With these locking bits in place, we can now remove the Giant
requirement from BPF, so drop the D_NEEDGIANT device flag.
This change removes Giant acquisitions around BPF device
handlers (read, write, ioctl etc).

MFC after:	1 month
Discussed with:	rwatson

1 files changed, 4 insertions, 3 deletions

diff --git a/sys/net/bpf.c b/sys/net/bpf.c
index 728bac2..506d15f 100644
--- a/sys/net/bpf.c
+++ b/sys/net/bpf.c
@@ -144,7 +144,6 @@ static	d_kqfilter_t	bpfkqfilter;
 
 static struct cdevsw bpf_cdevsw = {
 	.d_version =	D_VERSION,
-	.d_flags =	D_NEEDGIANT,
 	.d_open =	bpfopen,
 	.d_close =	bpfclose,
 	.d_read =	bpfread,
@@ -775,8 +774,10 @@ bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
 			if (d->bd_bif == NULL)
 				error = EINVAL;
 			else {
+				NET_LOCK_GIANT();
 				ifp = d->bd_bif->bif_ifp;
 				error = (*ifp->if_ioctl)(ifp, cmd, addr);
+				NET_UNLOCK_GIANT();
 			}
 			break;
 		}
@@ -834,9 +835,9 @@ bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
 			break;
 		}
 		if (d->bd_promisc == 0) {
-			mtx_lock(&Giant);
+			NET_LOCK_GIANT();
 			error = ifpromisc(d->bd_bif->bif_ifp, 1);
-			mtx_unlock(&Giant);
+			NET_UNLOCK_GIANT();
 			if (error == 0)
 				d->bd_promisc = 1;
 		}