Commit 5434da4d authored by Dong Jia Shi's avatar Dong Jia Shi Committed by Cornelia Huck
Browse files

s390: cio: introduce cio_cancel_halt_clear 



For future code reuse purpose, this decouples the cio code with
the ccw device specific parts from ccw_device_cancel_halt_clear,
and makes a new common I/O interface named cio_cancel_halt_clear.

Reviewed-by: default avatarPierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: default avatarDong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Acked-by: default avatarSebastian Ott <sebott@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-2-bjsdjshi@linux.vnet.ibm.com>
[CH: Fix typo]
Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
parent 97da3854

drivers/s390/cio/cio.c

+59 −0
Original line number Diff line number Diff line
@@ -309,6 +309,65 @@ cio_cancel (struct subchannel *sch) 
	}

}



/**

 * cio_cancel_halt_clear - Cancel running I/O by performing cancel, halt

 * and clear ordinally if subchannel is valid.

 * @sch: subchannel on which to perform the cancel_halt_clear operation

 * @iretry: the number of the times remained to retry the next operation

 *

 * This should be called repeatedly since halt/clear are asynchronous

 * operations. We do one try with cio_cancel, three tries with cio_halt,

 * 255 tries with cio_clear. The caller should initialize @iretry with

 * the value 255 for its first call to this, and keep using the same

 * @iretry in the subsequent calls until it gets a non -EBUSY return.

 *

 * Returns 0 if device now idle, -ENODEV for device not operational,

 * -EBUSY if an interrupt is expected (either from halt/clear or from a

 * status pending), and -EIO if out of retries.

 */

int cio_cancel_halt_clear(struct subchannel *sch, int *iretry)

{

	int ret;



	if (cio_update_schib(sch))

		return -ENODEV;

	if (!sch->schib.pmcw.ena)

		/* Not operational -> done. */

		return 0;

	/* Stage 1: cancel io. */

	if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&

	    !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {

		if (!scsw_is_tm(&sch->schib.scsw)) {

			ret = cio_cancel(sch);

			if (ret != -EINVAL)

				return ret;

		}

		/*

		 * Cancel io unsuccessful or not applicable (transport mode).

		 * Continue with asynchronous instructions.

		 */

		*iretry = 3;	/* 3 halt retries. */

	}

	/* Stage 2: halt io. */

	if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {

		if (*iretry) {

			*iretry -= 1;

			ret = cio_halt(sch);

			if (ret != -EBUSY)

				return (ret == 0) ? -EBUSY : ret;

		}

		/* Halt io unsuccessful. */

		*iretry = 255;	/* 255 clear retries. */

	}

	/* Stage 3: clear io. */

	if (*iretry) {

		*iretry -= 1;

		ret = cio_clear(sch);

		return (ret == 0) ? -EBUSY : ret;

	}

	/* Function was unsuccessful */

	return -EIO;

}



static void cio_apply_config(struct subchannel *sch, struct schib *schib)

{

drivers/s390/cio/cio.h

+1 −0
Original line number Diff line number Diff line
@@ -123,6 +123,7 @@ extern int cio_enable_subchannel(struct subchannel *, u32); 
extern int cio_disable_subchannel (struct subchannel *);

extern int cio_cancel (struct subchannel *);

extern int cio_clear (struct subchannel *);

extern int cio_cancel_halt_clear(struct subchannel *, int *);

extern int cio_resume (struct subchannel *);

extern int cio_halt (struct subchannel *);

extern int cio_start (struct subchannel *, struct ccw1 *, __u8);

drivers/s390/cio/device_fsm.c

+8 −46
Original line number Diff line number Diff line
@@ -124,14 +124,6 @@ ccw_device_set_timeout(struct ccw_device *cdev, int expires) 
	add_timer(&cdev->private->timer);

}



/*

 * Cancel running i/o. This is called repeatedly since halt/clear are

 * asynchronous operations. We do one try with cio_cancel, two tries

 * with cio_halt, 255 tries with cio_clear. If everythings fails panic.

 * Returns 0 if device now idle, -ENODEV for device not operational and

 * -EBUSY if an interrupt is expected (either from halt/clear or from a

 * status pending).

 */

int

ccw_device_cancel_halt_clear(struct ccw_device *cdev)

{
@@ -139,44 +131,14 @@ ccw_device_cancel_halt_clear(struct ccw_device *cdev) 
	int ret;



	sch = to_subchannel(cdev->dev.parent);

	if (cio_update_schib(sch))

		return -ENODEV; 

	if (!sch->schib.pmcw.ena)

		/* Not operational -> done. */

		return 0;

	/* Stage 1: cancel io. */

	if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&

	    !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {

		if (!scsw_is_tm(&sch->schib.scsw)) {

			ret = cio_cancel(sch);

			if (ret != -EINVAL)

				return ret;

		}

		/* cancel io unsuccessful or not applicable (transport mode).

		 * Continue with asynchronous instructions. */

		cdev->private->iretry = 3;	/* 3 halt retries. */

	}

	if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {

		/* Stage 2: halt io. */

		if (cdev->private->iretry) {

			cdev->private->iretry--;

			ret = cio_halt(sch);

			if (ret != -EBUSY)

				return (ret == 0) ? -EBUSY : ret;

		}

		/* halt io unsuccessful. */

		cdev->private->iretry = 255;	/* 255 clear retries. */

	}

	/* Stage 3: clear io. */

	if (cdev->private->iretry) {

		cdev->private->iretry--;

		ret = cio_clear (sch);

		return (ret == 0) ? -EBUSY : ret;

	}

	/* Function was unsuccessful */

	ret = cio_cancel_halt_clear(sch, &cdev->private->iretry);



	if (ret == -EIO)

		CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",

		      cdev->private->dev_id.ssid, cdev->private->dev_id.devno);

	return -EIO;

			      cdev->private->dev_id.ssid,

			      cdev->private->dev_id.devno);



	return ret;

}



void ccw_device_update_sense_data(struct ccw_device *cdev)

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