OpenCloudOS-Kernel/drivers/s390/cio/airq.c

96 lines
2.3 KiB
C

/*
* Support for adapter interruptions
*
* Copyright IBM Corp. 1999, 2007
* Author(s): Ingo Adlung <adlung@de.ibm.com>
* Cornelia Huck <cornelia.huck@de.ibm.com>
* Arnd Bergmann <arndb@de.ibm.com>
* Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
*/
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/rculist.h>
#include <linux/slab.h>
#include <asm/airq.h>
#include <asm/isc.h>
#include "cio.h"
#include "cio_debug.h"
#include "ioasm.h"
static DEFINE_SPINLOCK(airq_lists_lock);
static struct hlist_head airq_lists[MAX_ISC+1];
/**
* register_adapter_interrupt() - register adapter interrupt handler
* @airq: pointer to adapter interrupt descriptor
*
* Returns 0 on success, or -EINVAL.
*/
int register_adapter_interrupt(struct airq_struct *airq)
{
char dbf_txt[32];
if (!airq->handler || airq->isc > MAX_ISC)
return -EINVAL;
if (!airq->lsi_ptr) {
airq->lsi_ptr = kzalloc(1, GFP_KERNEL);
if (!airq->lsi_ptr)
return -ENOMEM;
airq->flags |= AIRQ_PTR_ALLOCATED;
}
if (!airq->lsi_mask)
airq->lsi_mask = 0xff;
snprintf(dbf_txt, sizeof(dbf_txt), "rairq:%p", airq);
CIO_TRACE_EVENT(4, dbf_txt);
isc_register(airq->isc);
spin_lock(&airq_lists_lock);
hlist_add_head_rcu(&airq->list, &airq_lists[airq->isc]);
spin_unlock(&airq_lists_lock);
return 0;
}
EXPORT_SYMBOL(register_adapter_interrupt);
/**
* unregister_adapter_interrupt - unregister adapter interrupt handler
* @airq: pointer to adapter interrupt descriptor
*/
void unregister_adapter_interrupt(struct airq_struct *airq)
{
char dbf_txt[32];
if (hlist_unhashed(&airq->list))
return;
snprintf(dbf_txt, sizeof(dbf_txt), "urairq:%p", airq);
CIO_TRACE_EVENT(4, dbf_txt);
spin_lock(&airq_lists_lock);
hlist_del_rcu(&airq->list);
spin_unlock(&airq_lists_lock);
synchronize_rcu();
isc_unregister(airq->isc);
if (airq->flags & AIRQ_PTR_ALLOCATED) {
kfree(airq->lsi_ptr);
airq->lsi_ptr = NULL;
airq->flags &= ~AIRQ_PTR_ALLOCATED;
}
}
EXPORT_SYMBOL(unregister_adapter_interrupt);
void do_adapter_IO(u8 isc)
{
struct airq_struct *airq;
struct hlist_head *head;
head = &airq_lists[isc];
rcu_read_lock();
hlist_for_each_entry_rcu(airq, head, list)
if ((*airq->lsi_ptr & airq->lsi_mask) != 0)
airq->handler(airq);
rcu_read_unlock();
}