haiku/headers/private/userlandfs/legacy/cache.h
Ingo Weinhold c10705cbda We do now provide the BeOS style FS add-ons with the kernel interface they
need via library libuserlandfs_beos_kernel.so. Fine-tuned the legacy headers
so they can by used by the the kernel interface emulation code as well as by
the add-ons. This is actually a bit hacky, since we build everything in the
Haiku build environment and thus mix these old headers and Haiku's.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20254 a95241bf-73f2-0310-859d-f6bbb57e9c96
2007-02-28 22:07:40 +00:00

123 lines
3.6 KiB
C

/*
Copyright 1999-2001, Be Incorporated. All Rights Reserved.
This file may be used under the terms of the Be Sample Code License.
*/
#ifndef _CACHE_H_
#define _CACHE_H_
#include <BeBuild.h>
#include <legacy/lock.h>
#ifndef _IMPEXP_KERNEL
#define _IMPEXP_KERNEL
#endif
typedef struct hash_ent {
int dev;
off_t bnum;
off_t hash_val;
void *data;
struct hash_ent *next;
} hash_ent;
typedef struct hash_table {
hash_ent **table;
int max;
int mask; /* == max - 1 */
int num_elements;
} hash_table;
#define HT_DEFAULT_MAX 128
typedef struct cache_ent {
int dev;
off_t block_num;
int bsize;
volatile int flags;
void *data;
void *clone; /* copy of data by set_block_info() */
int lock;
void (*func)(off_t bnum, size_t num_blocks, void *arg);
off_t logged_bnum;
void *arg;
struct cache_ent *next, /* points toward mru end of list */
*prev; /* points toward lru end of list */
} cache_ent;
#define CE_NORMAL 0x0000 /* a nice clean pristine page */
#define CE_DIRTY 0x0002 /* needs to be written to disk */
#define CE_BUSY 0x0004 /* this block has i/o happening, don't touch it */
typedef struct cache_ent_list {
cache_ent *lru; /* tail of the list */
cache_ent *mru; /* head of the list */
} cache_ent_list;
typedef struct block_cache {
struct lock lock;
int flags;
int cur_blocks;
int max_blocks;
hash_table ht;
cache_ent_list normal, /* list of "normal" blocks (clean & dirty) */
locked; /* list of clean and locked blocks */
} block_cache;
#if 0 /* XXXdbg -- need to deal with write through caches */
#define DC_WRITE_THROUGH 0x0001 /* cache is write-through (for floppies) */
#endif
#define ALLOW_WRITES 1
#define NO_WRITES 0
#ifdef __cplusplus
extern "C" {
#endif
extern _IMPEXP_KERNEL int init_block_cache(int max_blocks, int flags);
extern _IMPEXP_KERNEL void shutdown_block_cache(void);
extern _IMPEXP_KERNEL void force_cache_flush(int dev, int prefer_log_blocks);
extern _IMPEXP_KERNEL int flush_blocks(int dev, off_t bnum, int nblocks);
extern _IMPEXP_KERNEL int flush_device(int dev, int warn_locked);
extern _IMPEXP_KERNEL int init_cache_for_device(int fd, off_t max_blocks);
extern _IMPEXP_KERNEL int remove_cached_device_blocks(int dev, int allow_write);
extern _IMPEXP_KERNEL void *get_block(int dev, off_t bnum, int bsize);
extern _IMPEXP_KERNEL void *get_empty_block(int dev, off_t bnum, int bsize);
extern _IMPEXP_KERNEL int release_block(int dev, off_t bnum);
extern _IMPEXP_KERNEL int mark_blocks_dirty(int dev, off_t bnum, int nblocks);
extern _IMPEXP_KERNEL int cached_read(int dev, off_t bnum, void *data, off_t num_blocks, int bsize);
extern _IMPEXP_KERNEL int cached_write(int dev, off_t bnum, const void *data,
off_t num_blocks, int bsize);
extern _IMPEXP_KERNEL int cached_write_locked(int dev, off_t bnum, const void *data,
off_t num_blocks, int bsize);
extern _IMPEXP_KERNEL int set_blocks_info(int dev, off_t *blocks, int nblocks,
void (*func)(off_t bnum, size_t nblocks, void *arg),
void *arg);
extern _IMPEXP_KERNEL size_t read_phys_blocks (int fd, off_t bnum, void *data, uint num_blocks, int bsize);
extern _IMPEXP_KERNEL size_t write_phys_blocks(int fd, off_t bnum, void *data, uint num_blocks, int bsize);
#ifdef __cplusplus
} // extern "C"
#endif
#endif /* _CACHE_H_ */