device_ops.c

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/*
 *  drivers/s390/cio/device_ops.c
 *
 *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
 *			 IBM Corporation
 *    Author(s): Martin Schwidefsky ([e-mail])
 *               Cornelia Huck ([e-mail])
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/device.h>
#include <linux/delay.h>

#include <asm/ccwdev.h>
#include <asm/idals.h>
#include <asm/chpid.h>

#include "cio.h"
#include "cio_debug.h"
#include "css.h"
#include "chsc.h"
#include "device.h"
#include "chp.h"

/**
 * ccw_device_set_options_mask() - set some options and unset the rest
 * @cdev: device for which the options are to be set
 * @flags: options to be set
 *
 * All flags specified in @flags are set, all flags not specified in @flags
 * are cleared.
 * Returns:
 *   %0 on success, -%EINVAL on an invalid flag combination.
 */
int ccw_device_set_options_mask(struct ccw_device *cdev, unsigned long flags)
{
       /*
	* The flag usage is mutal exclusive ...
	*/
	if ((flags & CCWDEV_EARLY_NOTIFICATION) &&
	    (flags & CCWDEV_REPORT_ALL))
		return -EINVAL;
	cdev->private->options.fast = (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
	cdev->private->options.repall = (flags & CCWDEV_REPORT_ALL) != 0;
	cdev->private->options.pgroup = (flags & CCWDEV_DO_PATHGROUP) != 0;
	cdev->private->options.force = (flags & CCWDEV_ALLOW_FORCE) != 0;
	return 0;
}

/**
 * ccw_device_set_options() - set some options
 * @cdev: device for which the options are to be set
 * @flags: options to be set
 *
 * All flags specified in @flags are set, the remainder is left untouched.
 * Returns:
 *   %0 on success, -%EINVAL if an invalid flag combination would ensue.
 */
int ccw_device_set_options(struct ccw_device *cdev, unsigned long flags)
{
       /*
	* The flag usage is mutal exclusive ...
	*/
	if (((flags & CCWDEV_EARLY_NOTIFICATION) &&
	    (flags & CCWDEV_REPORT_ALL)) ||
	    ((flags & CCWDEV_EARLY_NOTIFICATION) &&
	     cdev->private->options.repall) ||
	    ((flags & CCWDEV_REPORT_ALL) &&
	     cdev->private->options.fast))
		return -EINVAL;
	cdev->private->options.fast |= (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
	cdev->private->options.repall |= (flags & CCWDEV_REPORT_ALL) != 0;
	cdev->private->options.pgroup |= (flags & CCWDEV_DO_PATHGROUP) != 0;
	cdev->private->options.force |= (flags & CCWDEV_ALLOW_FORCE) != 0;
	return 0;
}

/**
 * ccw_device_clear_options() - clear some options
 * @cdev: device for which the options are to be cleared
 * @flags: options to be cleared
 *
 * All flags specified in @flags are cleared, the remainder is left untouched.
 */
void ccw_device_clear_options(struct ccw_device *cdev, unsigned long flags)
{
	cdev->private->options.fast &= (flags & CCWDEV_EARLY_NOTIFICATION) == 0;
	cdev->private->options.repall &= (flags & CCWDEV_REPORT_ALL) == 0;
	cdev->private->options.pgroup &= (flags & CCWDEV_DO_PATHGROUP) == 0;
	cdev->private->options.force &= (flags & CCWDEV_ALLOW_FORCE) == 0;
}

/**
 * ccw_device_clear() - terminate I/O request processing
 * @cdev: target ccw device
 * @intparm: interruption parameter; value is only used if no I/O is
 *	     outstanding, otherwise the intparm associated with the I/O request
 *	     is returned
 *
 * ccw_device_clear() calls csch on @cdev's subchannel.
 * Returns:
 *  %0 on success,
 *  -%ENODEV on device not operational,
 *  -%EINVAL on invalid device state.
 * Context:
 *  Interrupts disabled, ccw device lock held
 */
int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
{
	struct subchannel *sch;
	int ret;

	if (!cdev)
		return -ENODEV;
	if (cdev->private->state == DEV_STATE_NOT_OPER)
		return -ENODEV;
	if (cdev->private->state != DEV_STATE_ONLINE &&
	    cdev->private->state != DEV_STATE_W4SENSE)
		return -EINVAL;
	sch = to_subchannel(cdev->dev.parent);
	if (!sch)
		return -ENODEV;
	ret = cio_clear(sch);
	if (ret == 0)
		cdev->private->intparm = intparm;
	return ret;
}

/**
 * ccw_device_start_key() - start a s390 channel program with key
 * @cdev: target ccw device
 * @cpa: logical start address of channel program
 * @intparm: user specific interruption parameter; will be presented back to
 *	     @cdev's interrupt handler. Allows a device driver to associate
 *	     the interrupt with a particular I/O request.
 * @lpm: defines the channel path to be used for a specific I/O request. A
 *	 value of 0 will make cio use the opm.
 * @key: storage key to be used for the I/O
 * @flags: additional flags; defines the action to be performed for I/O
 *	   processing.
 *
 * Start a S/390 channel program. When the interrupt arrives, the
 * IRQ handler is called, either immediately, delayed (dev-end missing,
 * or sense required) or never (no IRQ handler registered).
 * Returns:
 *  %0, if the operation was successful;
 *  -%EBUSY, if the device is busy, or status pending;
 *  -%EACCES, if no path specified in @lpm is operational;
 *  -%ENODEV, if the device is not operational.
 * Context:
 *  Interrupts disabled, ccw device lock held
 */
int ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
			 unsigned long intparm, __u8 lpm, __u8 key,
			 unsigned long flags)
{
	struct subchannel *sch;
	int ret;

	if (!cdev)
		return -ENODEV;
	sch = to_subchannel(cdev->dev.parent);
	if (!sch)
		return -ENODEV;
	if (cdev->private->state == DEV_STATE_NOT_OPER)
		return -ENODEV;
	if (cdev->private->state == DEV_STATE_VERIFY ||
	    cdev->private->state == DEV_STATE_CLEAR_VERIFY) {
		/* Remember to fake irb when finished. */
		if (!cdev->private->flags.fake_irb) {
			cdev->private->flags.fake_irb = 1;
			cdev->private->intparm = intparm;
			return 0;
		} else
			/* There's already a fake I/O around. */
			return -EBUSY;
	}
	if (cdev->private->state != DEV_STATE_ONLINE ||
	    ((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
	     !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
	    cdev->private->flags.doverify)
		return -EBUSY;
	ret = cio_set_options (sch, flags);
	if (ret)
		return ret;
	/* Adjust requested path mask to excluded varied off paths. */
	if (lpm) {
		lpm &= sch->opm;
		if (lpm == 0)
			return -EACCES;
	}
	ret = cio_start_key (sch, cpa, lpm, key);
	if (ret == 0)
		cdev->private->intparm = intparm;
	return ret;
}

/**
 * ccw_device_start_timeout_key() - start a s390 channel program with timeout and key
 * @cdev: target ccw device
 * @cpa: logical start address of channel program
 * @intparm: user specific interruption parameter; will be presented back to
 *	     @cdev's interrupt handler. Allows a device driver to associate
 *	     the interrupt with a particular I/O request.
 * @lpm: defines the channel path to be used for a specific I/O request. A
 *	 value of 0 will make cio use the opm.
 * @key: storage key to be used for the I/O
 * @flags: additional flags; defines the action to be performed for I/O
 *	   processing.
 * @expires: timeout value in jiffies
 *
 * Start a S/390 channel program. When the interrupt arrives, the
 * IRQ handler is called, either immediately, delayed (dev-end missing,
 * or sense required) or never (no IRQ handler registered).
 * This function notifies the device driver if the channel program has not
 * completed during the time specified by @expires. If a timeout occurs, the
 * channel program is terminated via xsch, hsch or csch, and the device's
 * interrupt handler will be called with an irb containing ERR_PTR(-%ETIMEDOUT).
 * Returns:
 *  %0, if the operation was successful;
 *  -%EBUSY, if the device is busy, or status pending;
 *  -%EACCES, if no path specified in @lpm is operational;
 *  -%ENODEV, if the device is not operational.
 * Context:
 *  Interrupts disabled, ccw device lock held
 */
int ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa,
				 unsigned long intparm, __u8 lpm, __u8 key,
				 unsigned long flags, int expires)
{
	int ret;

	if (!cdev)
		return -ENODEV;
	ccw_device_set_timeout(cdev, expires);
	ret = ccw_device_start_key(cdev, cpa, intparm, lpm, key, flags);
	if (ret != 0)
		ccw_device_set_timeout(cdev, 0);
	return ret;
}

/**
 * ccw_device_start() - start a s390 channel program
 * @cdev: target ccw device
 * @cpa: logical start address of channel program
 * @intparm: user specific interruption parameter; will be presented back to
 *	     @cdev's interrupt handler. Allows a device driver to associate
 *	     the interrupt with a particular I/O request.
 * @lpm: defines the channel path to be used for a specific I/O request. A
 *	 value of 0 will make cio use the opm.
 * @flags: additional flags; defines the action to be performed for I/O
 *	   processing.
 *
 * Start a S/390 channel program. When the interrupt arrives, the
 * IRQ handler is called, either immediately, delayed (dev-end missing,
 * or sense required) or never (no IRQ handler registered).
 * Returns:
 *  %0, if the operation was successful;
 *  -%EBUSY, if the device is busy, or status pending;
 *  -%EACCES, if no path specified in @lpm is operational;
 *  -%ENODEV, if the device is not operational.
 * Context:
 *  Interrupts disabled, ccw device lock held
 */
int ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa,
		     unsigned long intparm, __u8 lpm, unsigned long flags)
{
	return ccw_device_start_key(cdev, cpa, intparm, lpm,
				    PAGE_DEFAULT_KEY, flags);
}

/**
 * ccw_device_start_timeout() - start a s390 channel program with timeout
 * @cdev: target ccw device
 * @cpa: logical start address of channel program
 * @intparm: user specific interruption parameter; will be presented back to
 *	     @cdev's interrupt handler. Allows a device driver to associate
 *	     the interrupt with a particular I/O request.
 * @lpm: defines the channel path to be used for a specific I/O request. A
 *	 value of 0 will make cio use the opm.
 * @flags: additional flags; defines the action to be performed for I/O
 *	   processing.
 * @expires: timeout value in jiffies
 *
 * Start a S/390 channel program. When the interrupt arrives, the
 * IRQ handler is called, either immediately, delayed (dev-end missing,
 * or sense required) or never (no IRQ handler registered).
 * This function notifies the device driver if the channel program has not
 * completed during the time specified by @expires. If a timeout occurs, the
 * channel program is terminated via xsch, hsch or csch, and the device's
 * interrupt handler will be called with an irb containing ERR_PTR(-%ETIMEDOUT).