nvidia-open-gpu-kernel-modules/kernel-open/common/inc/nv-kref.h

62 lines
1.9 KiB
C

/*
* SPDX-FileCopyrightText: Copyright (c) 2017 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
* SPDX-License-Identifier: MIT
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#ifndef __NV_KREF_H__
#define __NV_KREF_H__
#include <asm/atomic.h>
typedef struct nv_kref
{
atomic_t refcount;
} nv_kref_t;
static inline void nv_kref_init(nv_kref_t *nv_kref)
{
atomic_set(&nv_kref->refcount, 1);
}
static inline void nv_kref_get(nv_kref_t *nv_kref)
{
atomic_inc(&nv_kref->refcount);
}
static inline int nv_kref_put(nv_kref_t *nv_kref,
void (*release)(nv_kref_t *nv_kref))
{
if (atomic_dec_and_test(&nv_kref->refcount))
{
release(nv_kref);
return 1;
}
return 0;
}
static inline unsigned int nv_kref_read(const nv_kref_t *nv_kref)
{
return atomic_read(&nv_kref->refcount);
}
#endif // __NV_KREF_H__