Commit 2a483d33 authored by Holger Dengler's avatar Holger Dengler Committed by Alexander Gordeev
Browse files

s390/chsc: use notifier for AP configuration changes 



The direct dependency of chsc and the AP bus prevents the
modularization of ap bus. Introduce a notifier interface for AP
changes, which decouples the producer of the change events (chsc) from
the consumer (ap_bus).

Remove the ap_cfg_chg() interface and replace it with the notifier
invocation. The ap bus module registers a notification handler, which
triggers the AP bus scan.

Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: default avatarHolger Dengler <dengler@linux.ibm.com>
Reviewed-by: default avatarHarald Freudenberger <freude@linux.ibm.com>
Acked-by: default avatarVineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent 05272aa4

arch/s390/include/asm/ap.h

+0 −11
Original line number Diff line number Diff line
@@ -549,15 +549,4 @@ static inline struct ap_queue_status ap_dqap(ap_qid_t qid, 
	return reg1.status;

}



/*

 * Interface to tell the AP bus code that a configuration

 * change has happened. The bus code should at least do

 * an ap bus resource rescan.

 */

#if IS_ENABLED(CONFIG_ZCRYPT)

void ap_bus_cfg_chg(void);

#else

static inline void ap_bus_cfg_chg(void){}

#endif



#endif /* _ASM_S390_AP_H_ */

arch/s390/include/asm/chsc.h

+15 −0
Original line number Diff line number Diff line
@@ -11,6 +11,9 @@ 


#include <uapi/asm/chsc.h>



/* struct from linux/notifier.h */

struct notifier_block;



/**

 * Operation codes for CHSC PNSO:

 *    PNSO_OC_NET_BRIDGE_INFO - only addresses that are visible to a bridgeport
@@ -66,4 +69,16 @@ struct chsc_pnso_area { 
	struct chsc_pnso_naid_l2 entries[];

} __packed __aligned(PAGE_SIZE);



/*

 * notifier interface - registered notifiers gets called on

 * the following events:

 * - ap config changed (CHSC_NOTIFY_AP_CFG)

 */

enum chsc_notify_type {

	CHSC_NOTIFY_AP_CFG = 3,

};



int chsc_notifier_register(struct notifier_block *nb);

int chsc_notifier_unregister(struct notifier_block *nb);



#endif /* _ASM_S390_CHSC_H */

drivers/s390/cio/chsc.c

+16 −2
Original line number Diff line number Diff line
@@ -24,7 +24,6 @@ 
#include <asm/crw.h>

#include <asm/isc.h>

#include <asm/ebcdic.h>

#include <asm/ap.h>



#include "css.h"

#include "cio.h"
@@ -40,6 +39,20 @@ static DEFINE_SPINLOCK(chsc_page_lock); 
#define SEI_VF_FLA	0xc0 /* VF flag for Full Link Address */

#define SEI_RS_CHPID	0x4  /* 4 in RS field indicates CHPID */



static BLOCKING_NOTIFIER_HEAD(chsc_notifiers);



int chsc_notifier_register(struct notifier_block *nb)

{

	return blocking_notifier_chain_register(&chsc_notifiers, nb);

}

EXPORT_SYMBOL(chsc_notifier_register);



int chsc_notifier_unregister(struct notifier_block *nb)

{

	return blocking_notifier_chain_unregister(&chsc_notifiers, nb);

}

EXPORT_SYMBOL(chsc_notifier_unregister);



/**

 * chsc_error_from_response() - convert a chsc response to an error

 * @response: chsc response code
@@ -581,7 +594,8 @@ static void chsc_process_sei_ap_cfg_chg(struct chsc_sei_nt0_area *sei_area) 
	if (sei_area->rs != 5)

		return;



	ap_bus_cfg_chg();

	blocking_notifier_call_chain(&chsc_notifiers,

				     CHSC_NOTIFY_AP_CFG, NULL);

}



static void chsc_process_sei_fces_event(struct chsc_sei_nt0_area *sei_area)

drivers/s390/crypto/ap_bus.c

+19 −2
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ 
#include <linux/ctype.h>

#include <linux/module.h>

#include <asm/uv.h>

#include <asm/chsc.h>



#include "ap_bus.h"

#include "ap_debug.h"
@@ -1024,13 +1025,23 @@ EXPORT_SYMBOL(ap_bus_force_rescan); 
/*

 * A config change has happened, force an ap bus rescan.

 */

void ap_bus_cfg_chg(void)

static int ap_bus_cfg_chg(struct notifier_block *nb,

			  unsigned long action, void *data)

{

	if (action != CHSC_NOTIFY_AP_CFG)

		return NOTIFY_DONE;



	pr_debug("%s config change, forcing bus rescan\n", __func__);



	ap_bus_force_rescan();



	return NOTIFY_OK;

}



static struct notifier_block ap_bus_nb = {

	.notifier_call = ap_bus_cfg_chg,

};



/*

 * hex2bitmap() - parse hex mask string and set bitmap.

 * Valid strings are "0x012345678" with at least one valid hex number.
@@ -2291,16 +2302,22 @@ static inline int __init ap_async_init(void) 


	queue_work(system_long_wq, &ap_scan_bus_work);



	rc = chsc_notifier_register(&ap_bus_nb);

	if (rc)

		goto out;



	/* Start the low priority AP bus poll thread. */

	if (!ap_thread_flag)

		return 0;



	rc = ap_poll_thread_start();

	if (rc)

		goto out;

		goto out_notifier;



	return 0;



out_notifier:

	chsc_notifier_unregister(&ap_bus_nb);

out:

	cancel_work(&ap_scan_bus_work);

	hrtimer_cancel(&ap_poll_timer);