Commit 672e405b authored by Ursula Braun's avatar Ursula Braun Committed by Martin Schwidefsky
Browse files

[S390] pm: iucv power management callbacks. 



Patch calls the PM callback functions of iucv-bus devices, which are
responsible for removal of their established iucv pathes.

The PM freeze callback for the first iucv-bus device disables all iucv
interrupts except the connection severed interrupt.
The PM freeze callback for the last iucv-bus device shuts down iucv.

The PM thaw callback for the first iucv-bus device re-enables iucv
if it has been shut down during freeze. If freezing has been interrupted,
it re-enables iucv interrupts according to the needs of iucv-exploiters.

The PM restore callback for the first iucv-bus device re-enables iucv.

Signed-off-by: default avatarUrsula Braun <ursula.braun@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 6c005961

net/iucv/iucv.c

+179 −0
Original line number Diff line number Diff line
@@ -11,6 +11,8 @@ 
 *	Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)

 *    Rewritten for af_iucv:

 *	Martin Schwidefsky <schwidefsky@de.ibm.com>

 *    PM functions:

 *	Ursula Braun (ursula.braun@de.ibm.com)

 *

 * Documentation used:

 *    The original source
@@ -77,9 +79,24 @@ static int iucv_bus_match(struct device *dev, struct device_driver *drv) 
	return 0;

}



static int iucv_pm_prepare(struct device *);

static void iucv_pm_complete(struct device *);

static int iucv_pm_freeze(struct device *);

static int iucv_pm_thaw(struct device *);

static int iucv_pm_restore(struct device *);



static struct dev_pm_ops iucv_pm_ops = {

	.prepare = iucv_pm_prepare,

	.complete = iucv_pm_complete,

	.freeze = iucv_pm_freeze,

	.thaw = iucv_pm_thaw,

	.restore = iucv_pm_restore,

};



struct bus_type iucv_bus = {

	.name = "iucv",

	.match = iucv_bus_match,

	.pm = &iucv_pm_ops,

};

EXPORT_SYMBOL(iucv_bus);
@@ -149,6 +166,7 @@ enum iucv_command_codes { 
	IUCV_RESUME = 14,

	IUCV_SEVER = 15,

	IUCV_SETMASK = 16,

	IUCV_SETCONTROLMASK = 17,

};



/*
@@ -366,6 +384,18 @@ static void iucv_allow_cpu(void *data) 
	parm->set_mask.ipmask = 0xf8;

	iucv_call_b2f0(IUCV_SETMASK, parm);



	/*

	 * Enable all iucv control interrupts.

	 * ipmask contains bits for the different interrupts

	 *	0x80 - Flag to allow pending connections interrupts

	 *	0x40 - Flag to allow connection complete interrupts

	 *	0x20 - Flag to allow connection severed interrupts

	 *	0x10 - Flag to allow connection quiesced interrupts

	 *	0x08 - Flag to allow connection resumed interrupts

	 */

	memset(parm, 0, sizeof(union iucv_param));

	parm->set_mask.ipmask = 0xf8;

	iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);

	/* Set indication that iucv interrupts are allowed for this cpu. */

	cpu_set(cpu, iucv_irq_cpumask);

}
@@ -390,6 +420,31 @@ static void iucv_block_cpu(void *data) 
	cpu_clear(cpu, iucv_irq_cpumask);

}



/**

 * iucv_block_cpu_almost

 * @data: unused

 *

 * Allow connection-severed interrupts only on this cpu.

 */

static void iucv_block_cpu_almost(void *data)

{

	int cpu = smp_processor_id();

	union iucv_param *parm;



	/* Allow iucv control interrupts only */

	parm = iucv_param_irq[cpu];

	memset(parm, 0, sizeof(union iucv_param));

	parm->set_mask.ipmask = 0x08;

	iucv_call_b2f0(IUCV_SETMASK, parm);

	/* Allow iucv-severed interrupt only */

	memset(parm, 0, sizeof(union iucv_param));

	parm->set_mask.ipmask = 0x20;

	iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);



	/* Clear indication that iucv interrupts are allowed for this cpu. */

	cpu_clear(cpu, iucv_irq_cpumask);

}



/**

 * iucv_declare_cpu

 * @data: unused
@@ -1766,6 +1821,130 @@ static void iucv_external_interrupt(u16 code) 
	spin_unlock(&iucv_queue_lock);

}



static int iucv_pm_prepare(struct device *dev)

{

	int rc = 0;



#ifdef CONFIG_PM_DEBUG

	printk(KERN_INFO "iucv_pm_prepare\n");

#endif

	if (dev->driver && dev->driver->pm && dev->driver->pm->prepare)

		rc = dev->driver->pm->prepare(dev);

	return rc;

}



static void iucv_pm_complete(struct device *dev)

{

#ifdef CONFIG_PM_DEBUG

	printk(KERN_INFO "iucv_pm_complete\n");

#endif

	if (dev->driver && dev->driver->pm && dev->driver->pm->complete)

		dev->driver->pm->complete(dev);

}



/**

 * iucv_path_table_empty() - determine if iucv path table is empty

 *

 * Returns 0 if there are still iucv pathes defined

 *	   1 if there are no iucv pathes defined

 */

int iucv_path_table_empty(void)

{

	int i;



	for (i = 0; i < iucv_max_pathid; i++) {

		if (iucv_path_table[i])

			return 0;

	}

	return 1;

}



/**

 * iucv_pm_freeze() - Freeze PM callback

 * @dev:	iucv-based device

 *

 * disable iucv interrupts

 * invoke callback function of the iucv-based driver

 * shut down iucv, if no iucv-pathes are established anymore

 */

static int iucv_pm_freeze(struct device *dev)

{

	int cpu;

	int rc = 0;



#ifdef CONFIG_PM_DEBUG

	printk(KERN_WARNING "iucv_pm_freeze\n");

#endif

	for_each_cpu_mask_nr(cpu, iucv_irq_cpumask)

		smp_call_function_single(cpu, iucv_block_cpu_almost, NULL, 1);

	if (dev->driver && dev->driver->pm && dev->driver->pm->freeze)

		rc = dev->driver->pm->freeze(dev);

	if (iucv_path_table_empty())

		iucv_disable();

	return rc;

}



/**

 * iucv_pm_thaw() - Thaw PM callback

 * @dev:	iucv-based device

 *

 * make iucv ready for use again: allocate path table, declare interrupt buffers

 *				  and enable iucv interrupts

 * invoke callback function of the iucv-based driver

 */

static int iucv_pm_thaw(struct device *dev)

{

	int rc = 0;



#ifdef CONFIG_PM_DEBUG

	printk(KERN_WARNING "iucv_pm_thaw\n");

#endif

	if (!iucv_path_table) {

		rc = iucv_enable();

		if (rc)

			goto out;

	}

	if (cpus_empty(iucv_irq_cpumask)) {

		if (iucv_nonsmp_handler)

			/* enable interrupts on one cpu */

			iucv_allow_cpu(NULL);

		else

			/* enable interrupts on all cpus */

			iucv_setmask_mp();

	}

	if (dev->driver && dev->driver->pm && dev->driver->pm->thaw)

		rc = dev->driver->pm->thaw(dev);

out:

	return rc;

}



/**

 * iucv_pm_restore() - Restore PM callback

 * @dev:	iucv-based device

 *

 * make iucv ready for use again: allocate path table, declare interrupt buffers

 *				  and enable iucv interrupts

 * invoke callback function of the iucv-based driver

 */

static int iucv_pm_restore(struct device *dev)

{

	int rc = 0;



#ifdef CONFIG_PM_DEBUG

	printk(KERN_WARNING "iucv_pm_restore %p\n", iucv_path_table);

#endif

	if (cpus_empty(iucv_irq_cpumask)) {

		rc = iucv_query_maxconn();

		rc = iucv_enable();

		if (rc)

			goto out;

	}

	if (dev->driver && dev->driver->pm && dev->driver->pm->restore)

		rc = dev->driver->pm->restore(dev);

out:

	return rc;

}



/**

 * iucv_init

 *

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