[PATCH v10 14/20] xen: introduce xenpv bus and a dummy pvcpu device

[Roger Pau Monne]

Since Xen PVH guests doesn't have ACPI, we need to create a dummy
bus so top level Xen devices can attach to it (instead of
attaching directly to the nexus) and a pvcpu device that will be used
to fill the pcpu->pc_device field.
---
 sys/conf/files.amd64 |    1 +
 sys/conf/files.i386  |    1 +
 sys/x86/xen/xenpv.c  |  128 ++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 130 insertions(+), 0 deletions(-)
 create mode 100644 sys/x86/xen/xenpv.c

diff --git a/sys/conf/files.amd64 b/sys/conf/files.amd64
index a3491da..d7c98cc 100644
--- a/sys/conf/files.amd64
+++ b/sys/conf/files.amd64
@@ -570,3 +570,4 @@ x86/xen/hvm.c			optional	xenhvm
 x86/xen/xen_intr.c		optional	xen | xenhvm
 x86/xen/pv.c			optional	xenhvm
 x86/xen/pvcpu_enum.c		optional	xenhvm
+x86/xen/xenpv.c			optional	xenhvm
diff --git a/sys/conf/files.i386 b/sys/conf/files.i386
index 790296d..81142e3 100644
--- a/sys/conf/files.i386
+++ b/sys/conf/files.i386
@@ -603,3 +603,4 @@ x86/x86/tsc.c			standard
 x86/x86/delay.c			standard
 x86/xen/hvm.c			optional xenhvm
 x86/xen/xen_intr.c		optional xen | xenhvm
+x86/xen/xenpv.c			optional xen | xenhvm
diff --git a/sys/x86/xen/xenpv.c b/sys/x86/xen/xenpv.c
new file mode 100644
index 0000000..e1282cf
--- /dev/null
+++ b/sys/x86/xen/xenpv.c
@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2013 Roger Pau Monné <roger.pau at citrix.com>
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 THE AUTHOR OR CONTRIBUTORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+#include <sys/kernel.h>
+#include <sys/module.h>
+#include <sys/pcpu.h>
+#include <sys/smp.h>
+
+#include <xen/xen-os.h>
+
+static devclass_t xenpv_devclass;
+
+static void
+xenpv_identify(driver_t *driver, device_t parent)
+{
+	if (!xen_domain())
+		return;
+
+	/* Make sure there's only one xenpv device. */
+	if (devclass_get_device(xenpv_devclass, 0))
+		return;
+
+	/*
+	 * Use a high order number so xenpv is attached after
+	 * xenpci on HVM guests.
+	 */
+	BUS_ADD_CHILD(parent, 200, "xenpv", 0);
+}
+
+static int
+xenpv_probe(device_t dev)
+{
+
+	device_set_desc(dev, "Xen PV bus");
+	device_quiet(dev);
+	return (BUS_PROBE_NOWILDCARD);
+}
+
+static int
+xenpv_attach(device_t dev)
+{
+	device_t child;
+
+	if (xen_hvm_domain()) {
+		device_t xenpci;
+		devclass_t dc;
+
+		/* Make sure xenpci has been attached */
+		dc = devclass_find("xenpci");
+		if (dc == NULL)
+			panic("unable to find xenpci devclass");
+
+		xenpci = devclass_get_device(dc, 0);
+		if (xenpci == NULL)
+			panic("unable to find xenpci device");
+
+		if (!device_is_attached(xenpci))
+			panic("trying to attach xenpv before xenpci");
+	}
+
+	/*
+	 * Let our child drivers identify any child devices that they
+	 * can find.  Once that is done attach any devices that we
+	 * found.
+	 */
+	bus_generic_probe(dev);
+	bus_generic_attach(dev);
+
+	if (!devclass_get_device(devclass_find("isa"), 0)) {
+		child = BUS_ADD_CHILD(dev, 0, "isa", 0);
+		if (child == NULL)
+			panic("xenpv_attach isa");
+		device_probe_and_attach(child);
+	}
+
+	return 0;
+}
+
+static device_method_t xenpv_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_identify,	xenpv_identify),
+	DEVMETHOD(device_probe,		xenpv_probe),
+	DEVMETHOD(device_attach,	xenpv_attach),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+
+	/* Bus interface */
+	DEVMETHOD(bus_add_child,	bus_generic_add_child),
+
+	DEVMETHOD_END
+};
+
+static driver_t xenpv_driver = {
+	"xenpv",
+	xenpv_methods,
+	1,			/* no softc */
+};
+
+DRIVER_MODULE(xenpv, nexus, xenpv_driver, xenpv_devclass, 0, 0);
-- 
1.7.7.5 (Apple Git-26)