Re: [PATCH] s390: crypto make ap_bus explicitly non-modular

[Paul Gortmaker <paul.gortmaker@windriver.com>]

[Re: [PATCH] s390: crypto make ap_bus explicitly non-modular] On 13/02/2017 (Mon 13:03) Harald Freudenberger wrote:

> On 02/09/2017 03:48 PM, Paul Gortmaker wrote:
> > The Makefile in drivers/s390 has:
> >
> > 	obj-y += cio/ block/ char/ crypto/ net/ scsi/ virtio/
> >
> > ..and the Makefile in crypto/ has:
> >
> > 	ap-objs := ap_bus.o ap_card.o ap_queue.o
> >
> > ...meaning that it currently is not being built as a module by anyone.
> >
> > Lets remove the modular code that is essentially orphaned, so that
> > when reading the driver there is no doubt it is builtin-only.
> >
> > Since module_init translates to device_initcall in the non-modular
> > case, the init ordering remains unchanged with this commit.
> >
> > Also note that MODULE_ALIAS is a no-op for non-module builds.
> >
> > We also delete the MODULE_LICENSE tag etc. since all that information
> > is already contained at the top of the file in the comments.
> >
> > We replace module.h with moduleparam.h since the file does declare
> > some module parameters even though it is not modular itself.
> >
> > Cc: Harald Freudenberger <freude@de.ibm.com>
> > Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
> > Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
> > Cc: linux-s390@vger.kernel.org
> > Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
> > ---
> >  drivers/s390/crypto/ap_bus.c | 54 +++-----------------------------------------
> >  1 file changed, 3 insertions(+), 51 deletions(-)
> >
> > diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
> > index 5fa699192864..7183a316f9be 100644
> > --- a/drivers/s390/crypto/ap_bus.c
> > +++ b/drivers/s390/crypto/ap_bus.c
> > @@ -27,7 +27,7 @@
> >  #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
> >
> >  #include <linux/kernel_stat.h>
> > -#include <linux/module.h>
> > +#include <linux/moduleparam.h>
> >  #include <linux/init.h>
> >  #include <linux/delay.h>
> >  #include <linux/err.h>
> > @@ -54,16 +54,7 @@
> >  #include "ap_debug.h"
> >
> >  /*
> > - * Module description.
> > - */
> > -MODULE_AUTHOR("IBM Corporation");
> > -MODULE_DESCRIPTION("Adjunct Processor Bus driver, " \
> > -		   "Copyright IBM Corp. 2006, 2012");
> > -MODULE_LICENSE("GPL");
> > -MODULE_ALIAS_CRYPTO("z90crypt");
> > -
> > -/*
> > - * Module parameter
> > + * Module parameters; note though this file itself isn't modular.
> >   */
> >  int ap_domain_index = -1;	/* Adjunct Processor Domain Index */
> >  static DEFINE_SPINLOCK(ap_domain_lock);
> > @@ -1270,43 +1261,4 @@ int __init ap_module_init(void)
> >  	kfree(ap_configuration);
> >  	return rc;
> >  }
> > -
> > -/**
> > - * ap_modules_exit(): The module termination code
> > - *
> > - * Terminates the module.
> > - */
> > -void ap_module_exit(void)
> > -{
> > -	int i;
> > -
> > -	initialised = false;
> > -	ap_reset_domain();
> > -	ap_poll_thread_stop();
> > -	del_timer_sync(&ap_config_timer);
> > -	hrtimer_cancel(&ap_poll_timer);
> > -	tasklet_kill(&ap_tasklet);
> > -
> > -	/* first remove queue devices */
> > -	bus_for_each_dev(&ap_bus_type, NULL, NULL,
> > -			 __ap_queue_devices_unregister);
> > -	/* now remove the card devices */
> > -	bus_for_each_dev(&ap_bus_type, NULL, NULL,
> > -			 __ap_card_devices_unregister);
> > -
> > -	/* remove bus attributes */
> > -	for (i = 0; ap_bus_attrs[i]; i++)
> > -		bus_remove_file(&ap_bus_type, ap_bus_attrs[i]);
> > -	unregister_pm_notifier(&ap_power_notifier);
> > -	root_device_unregister(ap_root_device);
> > -	bus_unregister(&ap_bus_type);
> > -	kfree(ap_configuration);
> > -	unregister_reset_call(&ap_reset_call);
> > -	if (ap_using_interrupts())
> > -		unregister_adapter_interrupt(&ap_airq);
> > -
> > -	ap_debug_exit();
> > -}
> > -
> > -module_init(ap_module_init);
> > -module_exit(ap_module_exit);
> > +device_initcall(ap_module_init);
> Thanks Paul for this patch.
> I am struggling with the change as I still like to build the ap device driver as a kernel module.
> It makes the development cycle somewhat easier to have this possibility with just a oneline
> change in the Makefile (replace obj-$(subst m,y,$(CONFIG_ZCRYPT)) += ap.o
> with obj-$(CONFIG_ZCRYPT) += ap.o).
> 
> However, you are right. As the ap driver is official not supported as a module the module
> code may get removed. Let me think about this some hours ...

May I suggest that if it can load and remove properly with the Makefile
change, that we change the Kconfig option to tristate and also change
the Makefile to match, and then anyone can build/debug it as you do.

Thanks,
Paul.
--

> 
> regards H.Freudenberger
> 
>