kernel_liteos_a/fs/vfs/include/path_cache.h

64 lines
2.8 KiB
C

/*
* Copyright (c) 2021-2021 Huawei Device Co., Ltd. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _PATH_CACHE_H
#define _PATH_CACHE_H
#include "los_list.h"
#include "fs/mount.h"
#include "vnode.h"
struct PathCache {
struct Vnode *parentVnode; /* vnode points to the cache */
struct Vnode *childVnode; /* vnode the cache points to */
LIST_ENTRY parentEntry; /* list entry for cache list in the parent vnode */
LIST_ENTRY childEntry; /* list entry for cache list in the child vnode */
LIST_ENTRY hashEntry; /* list entry for buckets in the hash table */
uint8_t nameLen; /* length of path component */
#ifdef LOSCFG_DEBUG_VERSION
int hit; /* cache hit count*/
#endif
char name[0]; /* path component name */
};
int PathCacheInit(void);
int PathCacheFree(struct PathCache *cache);
struct PathCache *PathCacheAlloc(struct Vnode *parent, struct Vnode *vnode, const char *name, uint8_t len);
int PathCacheLookup(struct Vnode *parent, const char *name, int len, struct Vnode **vnode);
void VnodePathCacheFree(struct Vnode *vnode);
void PathCacheMemoryDump(void);
void PathCacheDump(void);
LIST_HEAD* GetPathCacheList(void);
#ifdef LOSCFG_DEBUG_VERSION
void ResetPathCacheHitInfo(int *hit, int *try);
#endif
#endif /* _PATH_CACHE_H */