linux/fs/fat/cache.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/fs/fat/cache.c
 *
 *  Written 1992,1993 by Werner Almesberger
 *
 *  Mar 1999. AV. Changed cache, so that it uses the starting cluster instead
 *	of inode number.
 *  May 1999. AV. Fixed the bogosity with FAT32 (read "FAT28"). Fscking lusers.
 */

#include <linux/slab.h>
#include "fat.h"

/* this must be > 0. */
#define FAT_MAX_CACHE …

struct fat_cache { … };

struct fat_cache_id { … };

static inline int fat_max_cache(struct inode *inode)
{ … }

static struct kmem_cache *fat_cache_cachep;

static void init_once(void *foo)
{ … }

int __init fat_cache_init(void)
{ … }

void fat_cache_destroy(void)
{ … }

static inline struct fat_cache *fat_cache_alloc(struct inode *inode)
{ … }

static inline void fat_cache_free(struct fat_cache *cache)
{ … }

static inline void fat_cache_update_lru(struct inode *inode,
					struct fat_cache *cache)
{ … }

static int fat_cache_lookup(struct inode *inode, int fclus,
			    struct fat_cache_id *cid,
			    int *cached_fclus, int *cached_dclus)
{ … }

static struct fat_cache *fat_cache_merge(struct inode *inode,
					 struct fat_cache_id *new)
{ … }

static void fat_cache_add(struct inode *inode, struct fat_cache_id *new)
{ … }

/*
 * Cache invalidation occurs rarely, thus the LRU chain is not updated. It
 * fixes itself after a while.
 */
static void __fat_cache_inval_inode(struct inode *inode)
{ … }

void fat_cache_inval_inode(struct inode *inode)
{ … }

static inline int cache_contiguous(struct fat_cache_id *cid, int dclus)
{ … }

static inline void cache_init(struct fat_cache_id *cid, int fclus, int dclus)
{ … }

int fat_get_cluster(struct inode *inode, int cluster, int *fclus, int *dclus)
{ … }

static int fat_bmap_cluster(struct inode *inode, int cluster)
{ … }

int fat_get_mapped_cluster(struct inode *inode, sector_t sector,
			   sector_t last_block,
			   unsigned long *mapped_blocks, sector_t *bmap)
{ … }

static int is_exceed_eof(struct inode *inode, sector_t sector,
			 sector_t *last_block, int create)
{ … }

int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
	     unsigned long *mapped_blocks, int create, bool from_bmap)
{ … }