linux_dsm_epyc7002/drivers/s390/cio/isc.c
Greg Kroah-Hartman 724117b77b s390: cio: add SPDX identifiers to the remaining files
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/s390/cio/ files with the correct SPDX license
identifier based on the license text in the file itself.  The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-24 14:28:41 +01:00

70 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Functions for registration of I/O interruption subclasses on s390.
*
* Copyright IBM Corp. 2008
* Authors: Sebastian Ott <sebott@linux.vnet.ibm.com>
*/
#include <linux/spinlock.h>
#include <linux/module.h>
#include <asm/isc.h>
static unsigned int isc_refs[MAX_ISC + 1];
static DEFINE_SPINLOCK(isc_ref_lock);
/**
* isc_register - register an I/O interruption subclass.
* @isc: I/O interruption subclass to register
*
* The number of users for @isc is increased. If this is the first user to
* register @isc, the corresponding I/O interruption subclass mask is enabled.
*
* Context:
* This function must not be called in interrupt context.
*/
void isc_register(unsigned int isc)
{
if (isc > MAX_ISC) {
WARN_ON(1);
return;
}
spin_lock(&isc_ref_lock);
if (isc_refs[isc] == 0)
ctl_set_bit(6, 31 - isc);
isc_refs[isc]++;
spin_unlock(&isc_ref_lock);
}
EXPORT_SYMBOL_GPL(isc_register);
/**
* isc_unregister - unregister an I/O interruption subclass.
* @isc: I/O interruption subclass to unregister
*
* The number of users for @isc is decreased. If this is the last user to
* unregister @isc, the corresponding I/O interruption subclass mask is
* disabled.
* Note: This function must not be called if isc_register() hasn't been called
* before by the driver for @isc.
*
* Context:
* This function must not be called in interrupt context.
*/
void isc_unregister(unsigned int isc)
{
spin_lock(&isc_ref_lock);
/* check for misuse */
if (isc > MAX_ISC || isc_refs[isc] == 0) {
WARN_ON(1);
goto out_unlock;
}
if (isc_refs[isc] == 1)
ctl_clear_bit(6, 31 - isc);
isc_refs[isc]--;
out_unlock:
spin_unlock(&isc_ref_lock);
}
EXPORT_SYMBOL_GPL(isc_unregister);