Commit 22806dc1 authored by Cornelia Huck's avatar Cornelia Huck Committed by Heiko Carstens
Browse files

[S390] cio: Fix race for "fast" path gone/path back situations. 



Make sure we wait for previous evaluations triggered by path state
changes to have settled before we manipulate path states again.

Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
parent 374b8f45

drivers/s390/cio/chsc.c

+10 −2
Original line number Diff line number Diff line
@@ -217,6 +217,8 @@ void chsc_chp_offline(struct chp_id chpid) 


	if (chp_get_status(chpid) <= 0)

		return;

	/* Wait until previous actions have settled. */

	css_wait_for_slow_path();

	for_each_subchannel_staged(s390_subchannel_remove_chpid, NULL, &chpid);

}
@@ -303,7 +305,8 @@ static void s390_process_res_acc (struct res_acc_data *res_data) 
		sprintf(dbf_txt, "fla%x", res_data->fla);

		CIO_TRACE_EVENT( 2, dbf_txt);

	}



	/* Wait until previous actions have settled. */

	css_wait_for_slow_path();

	/*

	 * I/O resources may have become accessible.

	 * Scan through all subchannels that may be concerned and
@@ -561,10 +564,13 @@ void chsc_chp_online(struct chp_id chpid) 
	sprintf(dbf_txt, "cadd%x.%02x", chpid.cssid, chpid.id);

	CIO_TRACE_EVENT(2, dbf_txt);



	if (chp_get_status(chpid) != 0)

	if (chp_get_status(chpid) != 0) {

		/* Wait until previous actions have settled. */

		css_wait_for_slow_path();

		for_each_subchannel_staged(__chp_add, __chp_add_new_sch,

					   &chpid);

	}

}



static void __s390_subchannel_vary_chpid(struct subchannel *sch,

					 struct chp_id chpid, int on)
@@ -650,6 +656,8 @@ __s390_vary_chpid_on(struct subchannel_id schid, void *data) 
 */

int chsc_chp_vary(struct chp_id chpid, int on)

{

	/* Wait until previous actions have settled. */

	css_wait_for_slow_path();

	/*

	 * Redo PathVerification on the devices the chpid connects to

	 */

drivers/s390/cio/css.c

+6 −0
Original line number Diff line number Diff line
@@ -533,6 +533,12 @@ void css_schedule_eval_all(void) 
	spin_unlock_irqrestore(&slow_subchannel_lock, flags);

}



void css_wait_for_slow_path(void)

{

	flush_workqueue(ccw_device_notify_work);

	flush_workqueue(slow_path_wq);

}



/* Reprobe subchannel if unregistered. */

static int reprobe_subchannel(struct subchannel_id schid, void *data)

{

drivers/s390/cio/css.h

+1 −0
Original line number Diff line number Diff line
@@ -144,6 +144,7 @@ struct schib; 
int css_sch_is_valid(struct schib *);



extern struct workqueue_struct *slow_path_wq;

void css_wait_for_slow_path(void);



extern struct attribute_group *subch_attr_groups[];

#endif