1 files changed, 118 insertions, 0 deletions
diff --git a/sys/dev/usb/usb_ethersubr.c b/sys/dev/usb/usb_ethersubr.c
new file mode 100644
index 0000000..ded747e
--- /dev/null
+++ b/sys/dev/usb/usb_ethersubr.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 1997, 1998, 1999, 2000
+ *	Bill Paul <wpaul@ee.columbia.edu>.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Bill Paul.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * Callbacks in the USB code operate at splusb() (actually splbio()
+ * in FreeBSD). However adding packets to the input queues has to be
+ * done at splimp(). It is conceivable that this arrangement could
+ * trigger a condition where the splimp() is ignored and the input
+ * queues could get trampled in spite of our best effors to prevent
+ * it. To work around this, we implement a special input queue for
+ * USB ethernet adapter drivers. Rather than passing the frames directly
+ * to ether_input(), we pass them here, then schedule a soft interrupt
+ * to hand them to ether_input() later, outside of the USB interrupt
+ * context.
+ *
+ * It's questional as to whether this code should be expanded to
+ * handle other kinds of devices, or handle USB transfer callbacks
+ * in general. Right now, I need USB network interfaces to work
+ * properly.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/sockio.h>
+#include <sys/mbuf.h>
+#include <sys/kernel.h>
+#include <sys/socket.h>
+
+#include <net/if.h>
+#include <net/if_types.h>
+#include <net/if_arp.h>
+#include <net/ethernet.h>
+#include <net/netisr.h>
+
+#include <dev/usb/usb_ethersubr.h>
+
+#ifndef lint
+static const char rcsid[] =
+  "$FreeBSD$";
+#endif
+
+static struct ifqueue usbq;
+
+static void usbintr		__P((void));
+
+static void usbintr()
+{
+	struct ether_header	*eh;
+	struct mbuf		*m;
+	int			s;
+
+	s = splimp();
+
+	while(1) {
+		IF_DEQUEUE(&usbq, m);
+		if (m == NULL)
+			break;
+		eh = mtod(m, struct ether_header *);
+		m_adj(m, sizeof(struct ether_header));
+		ether_input(m->m_pkthdr.rcvif, eh, m);
+	}
+
+	splx(s);
+
+	return;
+}
+
+void usb_register_netisr()
+{
+	register_netisr(NETISR_USB, usbintr);
+	return;
+}
+
+/*
+ * Must be called at splusp() (actually splbio()). This should be
+ * the case when called from a transfer callback routine.
+ */
+void usb_ether_input(m)
+	struct mbuf		*m;
+{
+	int			s;
+	s = splimp();
+	IF_ENQUEUE(&usbq, m);
+	schednetisr(NETISR_USB);
+	splx(s);
+	return;
+}