Re: [PATCH] s390: Hypervisor File System

[Michael Holzheu <holzheu@de.ibm.com>]

Greg KH <greg@kroah.com> wrote on 05/04/2006 05:34:11 PM:
> > So you want a new config option CONFIG_HYPERVISOR?
> 
> Sure.  But don't make it a user selectable config option, but rather,
> one your S390 option sets.
> 
> That way the Xen and other groups can also set it when they need it.
> 

[snip]
> 
> The Xen people need it too.  Now who knows when their code will ever hit
> mainline...

I added a invisible config option CONFIG_SYS_HYPERVISOR. If this
option is enabled, /sys/hypervisor is created. CONFIG_S390_HYPFS
enables this option automatically using "select".

This the following patch acceptable for you?

---

 drivers/base/Kconfig      |    4 ++++
 drivers/base/Makefile     |    2 +-
 drivers/base/hypervisor.c |   30 ++++++++++++++++++++++++++++++
 drivers/base/init.c       |    1 +
 include/linux/kobject.h   |    4 ++++
 5 files changed, 40 insertions(+), 1 deletion(-)

diff -urpN linux-2.6.16/drivers/base/Kconfig linux-2.6.16-hypervisor/drivers/base/Kconfig
--- linux-2.6.16/drivers/base/Kconfig	2006-03-20 06:53:29.000000000 +0100
+++ linux-2.6.16-hypervisor/drivers/base/Kconfig	2006-05-05 15:13:10.000000000 +0200
@@ -38,3 +38,7 @@ config DEBUG_DRIVER
 	  If you are unsure about this, say N here.
 
 endmenu
+
+config SYS_HYPERVISOR
+	bool
+	default n
diff -urpN linux-2.6.16/drivers/base/Makefile linux-2.6.16-hypervisor/drivers/base/Makefile
--- linux-2.6.16/drivers/base/Makefile	2006-03-20 06:53:29.000000000 +0100
+++ linux-2.6.16-hypervisor/drivers/base/Makefile	2006-05-05 15:12:48.000000000 +0200
@@ -3,7 +3,7 @@
 obj-y			:= core.o sys.o bus.o dd.o \
 			   driver.o class.o platform.o \
 			   cpu.o firmware.o init.o map.o dmapool.o \
-			   attribute_container.o transport_class.o
+			   attribute_container.o transport_class.o hypervisor.o
 obj-y			+= power/
 obj-$(CONFIG_FW_LOADER)	+= firmware_class.o
 obj-$(CONFIG_NUMA)	+= node.o
diff -urpN linux-2.6.16/drivers/base/hypervisor.c linux-2.6.16-hypervisor/drivers/base/hypervisor.c
--- linux-2.6.16/drivers/base/hypervisor.c	1970-01-01 01:00:00.000000000 +0100
+++ linux-2.6.16-hypervisor/drivers/base/hypervisor.c	2006-05-05 15:12:57.000000000 +0200
@@ -0,0 +1,30 @@
+/*
+ * hypervisor.c - /sys/hypervisor subsystem.
+ *
+ * This file is released under the GPLv2
+ *
+ */
+
+#include <linux/kobject.h>
+#include <linux/device.h>
+
+#include "base.h"
+
+#ifdef CONFIG_SYS_HYPERVISOR
+
+decl_subsys(hypervisor, NULL, NULL);
+EXPORT_SYMBOL_GPL(hypervisor_subsys);
+
+int __init hypervisor_init(void)
+{
+	return subsystem_register(&hypervisor_subsys);
+}
+
+#else
+
+int __init hypervisor_init(void)
+{
+	return -1;
+}
+
+#endif /* CONFIG_SYS_HYPERVISOR */
diff -urpN linux-2.6.16/drivers/base/init.c linux-2.6.16-hypervisor/drivers/base/init.c
--- linux-2.6.16/drivers/base/init.c	2006-03-20 06:53:29.000000000 +0100
+++ linux-2.6.16-hypervisor/drivers/base/init.c	2006-05-05 15:12:40.000000000 +0200
@@ -27,6 +27,7 @@ void __init driver_init(void)
 	buses_init();
 	classes_init();
 	firmware_init();
+	hypervisor_init();
 
 	/* These are also core pieces, but must come after the
 	 * core core pieces.
diff -urpN linux-2.6.16/include/linux/kobject.h linux-2.6.16-hypervisor/include/linux/kobject.h
--- linux-2.6.16/include/linux/kobject.h	2006-03-20 06:53:29.000000000 +0100
+++ linux-2.6.16-hypervisor/include/linux/kobject.h	2006-05-05 15:13:35.000000000 +0200
@@ -186,6 +186,10 @@ struct subsystem _varname##_subsys = { \
 
 /* The global /sys/kernel/ subsystem for people to chain off of */
 extern struct subsystem kernel_subsys;
+#ifdef CONFIG_SYS_HYPERVISOR
+/* The global /sys/hypervisor/ subsystem  */
+extern struct subsystem hypervisor_subsys;
+#endif /* CONFIG_SYS_HYPERVISOR */
 
 /**
  * Helpers for setting the kset of registered objects.