Commit 1bc8927c authored by Sebastian Ott's avatar Sebastian Ott Committed by Martin Schwidefsky
Browse files

s390/cio: improve cio_commit_config 



The modify subchannel wrapper cio_commit_config can fail when
(unexpected) status is pending on the subchannel.

Callers of cio_commit_config (that operated on enabled subchannels)
needed to do error handling for that case (clear the unexpected
status with test subchannel and retry). This error handling is
missing in some code paths and caused online setting of devices to
fail.

Fix this for all callers by moving the error handling inside
cio_commit_config.

Reviewed-by: default avatarPeter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: default avatarSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 8d7f6690

drivers/s390/cio/cio.c

+14 −26
Original line number Diff line number Diff line
@@ -342,8 +342,9 @@ static int cio_check_config(struct subchannel *sch, struct schib *schib) 
 */

int cio_commit_config(struct subchannel *sch)

{

	struct schib schib;

	int ccode, retry, ret = 0;

	struct schib schib;

	struct irb irb;



	if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib))

		return -ENODEV;
@@ -367,7 +368,10 @@ int cio_commit_config(struct subchannel *sch) 
			ret = -EAGAIN;

			break;

		case 1: /* status pending */

			return -EBUSY;

			ret = -EBUSY;

			if (tsch(sch->schid, &irb))

				return ret;

			break;

		case 2: /* busy */

			udelay(100); /* allow for recovery */

			ret = -EBUSY;
@@ -403,7 +407,6 @@ EXPORT_SYMBOL_GPL(cio_update_schib); 
 */

int cio_enable_subchannel(struct subchannel *sch, u32 intparm)

{

	int retry;

	int ret;



	CIO_TRACE_EVENT(2, "ensch");
@@ -418,7 +421,6 @@ int cio_enable_subchannel(struct subchannel *sch, u32 intparm) 
	sch->config.isc = sch->isc;

	sch->config.intparm = intparm;



	for (retry = 0; retry < 3; retry++) {

	ret = cio_commit_config(sch);

	if (ret == -EIO) {

		/*
@@ -426,12 +428,7 @@ int cio_enable_subchannel(struct subchannel *sch, u32 intparm) 
		 * the concurrent sense bit the next time.

		 */

		sch->config.csense = 0;

		} else if (ret == -EBUSY) {

			struct irb irb;

			if (tsch(sch->schid, &irb) != 0)

				break;

		} else

			break;

		ret = cio_commit_config(sch);

	}

	CIO_HEX_EVENT(2, &ret, sizeof(ret));

	return ret;
@@ -444,7 +441,6 @@ EXPORT_SYMBOL_GPL(cio_enable_subchannel); 
 */

int cio_disable_subchannel(struct subchannel *sch)

{

	int retry;

	int ret;



	CIO_TRACE_EVENT(2, "dissch");
@@ -456,16 +452,8 @@ int cio_disable_subchannel(struct subchannel *sch) 
		return -ENODEV;



	sch->config.ena = 0;



	for (retry = 0; retry < 3; retry++) {

	ret = cio_commit_config(sch);

		if (ret == -EBUSY) {

			struct irb irb;

			if (tsch(sch->schid, &irb) != 0)

				break;

		} else

			break;

	}



	CIO_HEX_EVENT(2, &ret, sizeof(ret));

	return ret;

}

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