Split out a more generic debugnet(4) from netdump(4)

Debugnet is a simplistic and specialized panic- or debug-time reliable
datagram transport.  It can drive a single connection at a time and is
currently unidirectional (debug/panic machine transmit to remote server
only).

It is mostly a verbatim code lift from netdump(4).  Netdump(4) remains
the only consumer (until the rest of this patch series lands).

The INET-specific logic has been extracted somewhat more thoroughly than
previously in netdump(4), into debugnet_inet.c.  UDP-layer logic and up, as
much as possible as is protocol-independent, remains in debugnet.c.  The
separation is not perfect and future improvement is welcome.  Supporting
INET6 is a long-term goal.

Much of the diff is "gratuitous" renaming from 'netdump_' or 'nd_' to
'debugnet_' or 'dn_' -- sorry.  I thought keeping the netdump name on the
generic module would be more confusing than the refactoring.

The only functional change here is the mbuf allocation / tracking.  Instead
of initiating solely on netdump-configured interface(s) at dumpon(8)
configuration time, we watch for any debugnet-enabled NIC for link
activation and query it for mbuf parameters at that time.  If they exceed
the existing high-water mark allocation, we re-allocate and track the new
high-water mark.  Otherwise, we leave the pre-panic mbuf allocation alone.
In a future patch in this series, this will allow initiating netdump from
panic ddb(4) without pre-panic configuration.

No other functional change intended.

Reviewed by:	markj (earlier version)
Some discussion with:	emaste, jhb
Objection from:	marius
Differential Revision:	https://reviews.freebsd.org/D21421

1 files changed, 11 insertions, 11 deletions

diff --git a/sys/dev/bge/if_bge.c b/sys/dev/bge/if_bge.c
index bae18acf96ae..30b8c9ac76b3 100644
--- a/sys/dev/bge/if_bge.c
+++ b/sys/dev/bge/if_bge.c
@@ -84,6 +84,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/sysctl.h>
 #include <sys/taskqueue.h>
 
+#include <net/debugnet.h>
 #include <net/if.h>
 #include <net/if_var.h>
 #include <net/if_arp.h>
@@ -100,7 +101,6 @@ __FBSDID("$FreeBSD$");
 #include <netinet/in.h>
 #include <netinet/ip.h>
 #include <netinet/tcp.h>
-#include <netinet/netdump/netdump.h>
 
 #include <machine/bus.h>
 #include <machine/resource.h>
@@ -519,7 +519,7 @@ static void bge_add_sysctl_stats(struct bge_softc *, struct sysctl_ctx_list *,
     struct sysctl_oid_list *);
 static int bge_sysctl_stats(SYSCTL_HANDLER_ARGS);
 
-NETDUMP_DEFINE(bge);
+DEBUGNET_DEFINE(bge);
 
 static device_method_t bge_methods[] = {
 	/* Device interface */
@@ -3983,8 +3983,8 @@ again:
 		goto fail;
 	}
 
-	/* Attach driver netdump methods. */
-	NETDUMP_SET(ifp, bge);
+	/* Attach driver debugnet methods. */
+	DEBUGNET_SET(ifp, bge);
 
 fail:
 	if (error)
@@ -6844,16 +6844,16 @@ bge_get_counter(if_t ifp, ift_counter cnt)
 	}
 }
 
-#ifdef NETDUMP
+#ifdef DEBUGNET
 static void
-bge_netdump_init(if_t ifp, int *nrxr, int *ncl, int *clsize)
+bge_debugnet_init(if_t ifp, int *nrxr, int *ncl, int *clsize)
 {
 	struct bge_softc *sc;
 
 	sc = if_getsoftc(ifp);
 	BGE_LOCK(sc);
 	*nrxr = sc->bge_return_ring_cnt;
-	*ncl = NETDUMP_MAX_IN_FLIGHT;
+	*ncl = DEBUGNET_MAX_IN_FLIGHT;
 	if ((sc->bge_flags & BGE_FLAG_JUMBO_STD) != 0 &&
 	    (if_getmtu(sc->bge_ifp) + ETHER_HDR_LEN + ETHER_CRC_LEN +
 	    ETHER_VLAN_ENCAP_LEN > (MCLBYTES - ETHER_ALIGN)))
@@ -6864,12 +6864,12 @@ bge_netdump_init(if_t ifp, int *nrxr, int *ncl, int *clsize)
 }
 
 static void
-bge_netdump_event(if_t ifp __unused, enum netdump_ev event __unused)
+bge_debugnet_event(if_t ifp __unused, enum debugnet_ev event __unused)
 {
 }
 
 static int
-bge_netdump_transmit(if_t ifp, struct mbuf *m)
+bge_debugnet_transmit(if_t ifp, struct mbuf *m)
 {
 	struct bge_softc *sc;
 	uint32_t prodidx;
@@ -6888,7 +6888,7 @@ bge_netdump_transmit(if_t ifp, struct mbuf *m)
 }
 
 static int
-bge_netdump_poll(if_t ifp, int count)
+bge_debugnet_poll(if_t ifp, int count)
 {
 	struct bge_softc *sc;
 	uint32_t rx_prod, tx_cons;
@@ -6913,4 +6913,4 @@ bge_netdump_poll(if_t ifp, int count)
 	bge_txeof(sc, tx_cons);
 	return (0);
 }
-#endif /* NETDUMP */
+#endif /* DEBUGNET */