[PATCH] xen: rename gntdev and evtdev modules to be less generic

[PATCH] xen: rename gntdev and evtdev modules to be less generic

[Ian Campbell]

Also allow gntdev to be built as a module.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
---
 drivers/xen/Kconfig  |    2 +-
 drivers/xen/Makefile |    7 +++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index 22c8818..a2833bb 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -169,7 +169,7 @@ config XEN_S3
        depends on XEN_DOM0 && ACPI
        
 config XEN_GNTDEV
-	bool "userspace grant access device driver"
+	tristate "userspace grant access device driver"
 	depends on XEN
 	select MMU_NOTIFIER
 	help
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index f7893f3..3288930 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -8,8 +8,8 @@ obj-$(CONFIG_PCI)			+= pci.o
 obj-$(CONFIG_HOTPLUG_CPU)		+= cpu_hotplug.o
 obj-$(CONFIG_XEN_XENCOMM)		+= xencomm.o
 obj-$(CONFIG_XEN_BALLOON)		+= balloon.o
-obj-$(CONFIG_XEN_DEV_EVTCHN)		+= evtchn.o
-obj-$(CONFIG_XEN_GNTDEV)		+= gntdev.o
+obj-$(CONFIG_XEN_DEV_EVTCHN)		+= xen-evtchn.o
+obj-$(CONFIG_XEN_GNTDEV)		+= xen-gntdev.o
 obj-$(CONFIG_XEN_BLKDEV_BACKEND)	+= blkback/
 obj-$(CONFIG_XEN_BLKDEV_TAP)            += blktap/
 obj-$(CONFIG_XEN_NETDEV_BACKEND)	+= netback/
@@ -19,3 +19,6 @@ obj-$(CONFIG_XEN_SYS_HYPERVISOR)	+= sys-hypervisor.o
 obj-$(CONFIG_XEN_S3)			+= acpi.o
 obj-$(CONFIG_XEN_MCE)			+= mce.o
 obj-$(CONFIG_ACPI_PROCESSOR_XEN)	+= acpi_processor.o
+
+xen-evtchn-y				:= evtchn.o
+xen-gntdev-y				:= gntdev.o
-- 
1.6.5.3

Re: [PATCH] xen: rename gntdev and evtdev modules to be less generic

[Jeremy Fitzhardinge]

On 12/06/09 03:07, Ian Campbell wrote:
> Also allow gntdev to be built as a module.
>    

I'm thinking of dropping gntdev; it doesn't work at present (ends up 
trying to take a mutex in a spinlock), and I don't think it has any users.

     J
> Signed-off-by: Ian Campbell<ian.campbell@citrix.com>
> Cc: Jeremy Fitzhardinge<jeremy@goop.org>
> ---
>   drivers/xen/Kconfig  |    2 +-
>   drivers/xen/Makefile |    7 +++++--
>   2 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
> index 22c8818..a2833bb 100644
> --- a/drivers/xen/Kconfig
> +++ b/drivers/xen/Kconfig
> @@ -169,7 +169,7 @@ config XEN_S3
>          depends on XEN_DOM0&&  ACPI
>
>   config XEN_GNTDEV
> -	bool "userspace grant access device driver"
> +	tristate "userspace grant access device driver"
>   	depends on XEN
>   	select MMU_NOTIFIER
>   	help
> diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
> index f7893f3..3288930 100644
> --- a/drivers/xen/Makefile
> +++ b/drivers/xen/Makefile
> @@ -8,8 +8,8 @@ obj-$(CONFIG_PCI)			+= pci.o
>   obj-$(CONFIG_HOTPLUG_CPU)		+= cpu_hotplug.o
>   obj-$(CONFIG_XEN_XENCOMM)		+= xencomm.o
>   obj-$(CONFIG_XEN_BALLOON)		+= balloon.o
> -obj-$(CONFIG_XEN_DEV_EVTCHN)		+= evtchn.o
> -obj-$(CONFIG_XEN_GNTDEV)		+= gntdev.o
> +obj-$(CONFIG_XEN_DEV_EVTCHN)		+= xen-evtchn.o
> +obj-$(CONFIG_XEN_GNTDEV)		+= xen-gntdev.o
>   obj-$(CONFIG_XEN_BLKDEV_BACKEND)	+= blkback/
>   obj-$(CONFIG_XEN_BLKDEV_TAP)            += blktap/
>   obj-$(CONFIG_XEN_NETDEV_BACKEND)	+= netback/
> @@ -19,3 +19,6 @@ obj-$(CONFIG_XEN_SYS_HYPERVISOR)	+= sys-hypervisor.o
>   obj-$(CONFIG_XEN_S3)			+= acpi.o
>   obj-$(CONFIG_XEN_MCE)			+= mce.o
>   obj-$(CONFIG_ACPI_PROCESSOR_XEN)	+= acpi_processor.o
> +
> +xen-evtchn-y				:= evtchn.o
> +xen-gntdev-y				:= gntdev.o
>    

RE: Re: [PATCH] xen: rename gntdev and evtdev modules to beless generic

[James Harper]

> 
> I'm thinking of dropping gntdev; it doesn't work at present (ends up
> trying to take a mutex in a spinlock), and I don't think it has any
users.
> 

>From memory I think that there is a glx passthrough project that makes
use of it

James

Re: Re: [PATCH] xen: rename gntdev and evtdev modules to beless generic

[Jeremy Fitzhardinge]

On 12/07/09 16:29, James Harper wrote:
>> I'm thinking of dropping gntdev; it doesn't work at present (ends up
>> trying to take a mutex in a spinlock), and I don't think it has any
>>      
> users.
>    
>>      
>  From memory I think that there is a glx passthrough project that makes
> use of it
>    

I don't think there's anything that can't be fixed; its just some locks 
got moved around.  I'll mark it BROKEN for now.

     J

Re: [PATCH] xen: rename gntdev and evtdev modules to be less generic

[Jeremy Fitzhardinge]

On 12/06/09 03:07, Ian Campbell wrote:
> Also allow gntdev to be built as a module.
>    

I think this breaks auto-loading of evtchn when its a module; I suspect 
xen-backend.rules needs updating to match.

     J

> Signed-off-by: Ian Campbell<ian.campbell@citrix.com>
> Cc: Jeremy Fitzhardinge<jeremy@goop.org>
> ---
>   drivers/xen/Kconfig  |    2 +-
>   drivers/xen/Makefile |    7 +++++--
>   2 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
> index 22c8818..a2833bb 100644
> --- a/drivers/xen/Kconfig
> +++ b/drivers/xen/Kconfig
> @@ -169,7 +169,7 @@ config XEN_S3
>          depends on XEN_DOM0&&  ACPI
>
>   config XEN_GNTDEV
> -	bool "userspace grant access device driver"
> +	tristate "userspace grant access device driver"
>   	depends on XEN
>   	select MMU_NOTIFIER
>   	help
> diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
> index f7893f3..3288930 100644
> --- a/drivers/xen/Makefile
> +++ b/drivers/xen/Makefile
> @@ -8,8 +8,8 @@ obj-$(CONFIG_PCI)			+= pci.o
>   obj-$(CONFIG_HOTPLUG_CPU)		+= cpu_hotplug.o
>   obj-$(CONFIG_XEN_XENCOMM)		+= xencomm.o
>   obj-$(CONFIG_XEN_BALLOON)		+= balloon.o
> -obj-$(CONFIG_XEN_DEV_EVTCHN)		+= evtchn.o
> -obj-$(CONFIG_XEN_GNTDEV)		+= gntdev.o
> +obj-$(CONFIG_XEN_DEV_EVTCHN)		+= xen-evtchn.o
> +obj-$(CONFIG_XEN_GNTDEV)		+= xen-gntdev.o
>   obj-$(CONFIG_XEN_BLKDEV_BACKEND)	+= blkback/
>   obj-$(CONFIG_XEN_BLKDEV_TAP)            += blktap/
>   obj-$(CONFIG_XEN_NETDEV_BACKEND)	+= netback/
> @@ -19,3 +19,6 @@ obj-$(CONFIG_XEN_SYS_HYPERVISOR)	+= sys-hypervisor.o
>   obj-$(CONFIG_XEN_S3)			+= acpi.o
>   obj-$(CONFIG_XEN_MCE)			+= mce.o
>   obj-$(CONFIG_ACPI_PROCESSOR_XEN)	+= acpi_processor.o
> +
> +xen-evtchn-y				:= evtchn.o
> +xen-gntdev-y				:= gntdev.o
>    

Re: [PATCH] xen: rename gntdev and evtdev modules to be less generic

[Ian Campbell]

On Thu, 2009-12-10 at 21:10 +0000, Jeremy Fitzhardinge wrote: 
> On 12/06/09 03:07, Ian Campbell wrote:
> > Also allow gntdev to be built as a module.
> >    
> 
> I think this breaks auto-loading of evtchn when its a module;

It never occurred to me that autoloading would work at all for this
driver, I always just load the module explicitly by listing
in /etc/modules. What triggers (or is supposed to trigger) autoloading?

> I suspect xen-backend.rules needs updating to match.

That is only to do with making sure the node gets called /dev/xen/evtchn
(presumably it would be /dev/evtchn, now /dev/xen-evtchn, otherwise).
This works for me.

Ian.

Re: [PATCH] xen: rename gntdev and evtdev modules to be less generic

[Jeremy Fitzhardinge]

On 12/10/09 14:50, Ian Campbell wrote:
> It never occurred to me that autoloading would work at all for this
> driver, I always just load the module explicitly by listing
> in /etc/modules. What triggers (or is supposed to trigger) autoloading?
>    

Magic earwigs?  How to misc drivers get autoloaded in general?  Possibly 
not at all.

I always thought it used to work.  Oh well, I made it a builtin.

     J

Re: [PATCH] xen: rename gntdev and evtdev modules to be less generic

[Ian Campbell]

On Thu, 2009-12-10 at 23:25 +0000, Jeremy Fitzhardinge wrote: 
> On 12/10/09 14:50, Ian Campbell wrote:
> > It never occurred to me that autoloading would work at all for this
> > driver, I always just load the module explicitly by listing
> > in /etc/modules. What triggers (or is supposed to trigger) autoloading?
> >    
> 
> Magic earwigs?  How to misc drivers get autoloaded in general?

In the absence of an explicit request_module or module alias which
matches a device on a bus somewhere I don't think anything much has been
autoloaded since udev came along since the only other way was the old
"open a device node with no driver" method and udev effectively removed
those device nodes.

A module alias won't work since there is no device on a bus which could
match this driver and I can't find a request_module for evtchn anywhere.
If we think this driver should always get loaded when Xen is running
then I think a late_initcall which calls request_module might be the way
to go, although I'm not sure late_initcall is late enough sine it needs
to be when the proper root is mounted.

Ian.

Re: [PATCH] xen: rename gntdev and evtdev modules to be less generic

[Ian Campbell]

On Thu, 2009-12-10 at 23:25 +0000, Jeremy Fitzhardinge wrote:
> On 12/10/09 14:50, Ian Campbell wrote:
> > It never occurred to me that autoloading would work at all for this
> > driver, I always just load the module explicitly by listing
> > in /etc/modules. What triggers (or is supposed to trigger) autoloading?
> >    
> 
> Magic earwigs?  How to misc drivers get autoloaded in general?  Possibly 
> not at all.
> 
> I always thought it used to work.  Oh well, I made it a builtin.

I guess you are using Fedora? Looks
like /etc/sysconfig/modules/xen.modules needs updating.

I've cc'd the two most recently listed people in the xen.spec changelog.

Gerd, Justin, the {evtchn,blkbk,netbk}.ko modules are going to be
renamed to xen-{evtchn,blkback,netback}.ko at some point in the future.

Ian.

Re: [PATCH] xen: rename gntdev and evtdev modules to be less generic

[Gerd Hoffmann]

On 12/11/09 12:50, Ian Campbell wrote:
> Gerd, Justin, the {evtchn,blkbk,netbk}.ko modules are going to be
> renamed to xen-{evtchn,blkback,netback}.ko at some point in the future.

New packages (3.4.2 update + this one) are going to enter rawhide and 
f12-updates-testing soon.

cheers,
   Gerd