mirror of https://gitee.com/openkylin/linux.git
150 lines
4.3 KiB
C
150 lines
4.3 KiB
C
/*
|
|
* JFFS -- Journaling Flash File System, Linux implementation.
|
|
*
|
|
* Copyright (C) 1999, 2000 Axis Communications AB.
|
|
*
|
|
* Created by Finn Hakansson <finn@axis.com>.
|
|
*
|
|
* This is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* $Id: jffs_fm.h,v 1.13 2001/01/11 12:03:25 dwmw2 Exp $
|
|
*
|
|
* Ported to Linux 2.3.x and MTD:
|
|
* Copyright (C) 2000 Alexander Larsson (alex@cendio.se), Cendio Systems AB
|
|
*
|
|
*/
|
|
|
|
#ifndef __LINUX_JFFS_FM_H__
|
|
#define __LINUX_JFFS_FM_H__
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/jffs.h>
|
|
#include <linux/mtd/mtd.h>
|
|
#include <linux/mutex.h>
|
|
|
|
/* The alignment between two nodes in the flash memory. */
|
|
#define JFFS_ALIGN_SIZE 4
|
|
|
|
/* Mark the on-flash space as obsolete when appropriate. */
|
|
#define JFFS_MARK_OBSOLETE 0
|
|
|
|
#ifndef CONFIG_JFFS_FS_VERBOSE
|
|
#define CONFIG_JFFS_FS_VERBOSE 1
|
|
#endif
|
|
|
|
#if CONFIG_JFFS_FS_VERBOSE > 0
|
|
#define D(x) x
|
|
#define D1(x) D(x)
|
|
#else
|
|
#define D(x)
|
|
#define D1(x)
|
|
#endif
|
|
|
|
#if CONFIG_JFFS_FS_VERBOSE > 1
|
|
#define D2(x) D(x)
|
|
#else
|
|
#define D2(x)
|
|
#endif
|
|
|
|
#if CONFIG_JFFS_FS_VERBOSE > 2
|
|
#define D3(x) D(x)
|
|
#else
|
|
#define D3(x)
|
|
#endif
|
|
|
|
#define ASSERT(x) x
|
|
|
|
/* How many padding bytes should be inserted between two chunks of data
|
|
on the flash? */
|
|
#define JFFS_GET_PAD_BYTES(size) ( (JFFS_ALIGN_SIZE-1) & -(__u32)(size) )
|
|
#define JFFS_PAD(size) ( (size + (JFFS_ALIGN_SIZE-1)) & ~(JFFS_ALIGN_SIZE-1) )
|
|
|
|
|
|
|
|
struct jffs_node_ref
|
|
{
|
|
struct jffs_node *node;
|
|
struct jffs_node_ref *next;
|
|
};
|
|
|
|
|
|
/* The struct jffs_fm represents a chunk of data in the flash memory. */
|
|
struct jffs_fm
|
|
{
|
|
__u32 offset;
|
|
__u32 size;
|
|
struct jffs_fm *prev;
|
|
struct jffs_fm *next;
|
|
struct jffs_node_ref *nodes; /* USED if != 0. */
|
|
};
|
|
|
|
struct jffs_fmcontrol
|
|
{
|
|
__u32 flash_size;
|
|
__u32 used_size;
|
|
__u32 dirty_size;
|
|
__u32 free_size;
|
|
__u32 sector_size;
|
|
__u32 min_free_size; /* The minimum free space needed to be able
|
|
to perform garbage collections. */
|
|
__u32 max_chunk_size; /* The maximum size of a chunk of data. */
|
|
struct mtd_info *mtd;
|
|
struct jffs_control *c;
|
|
struct jffs_fm *head;
|
|
struct jffs_fm *tail;
|
|
struct jffs_fm *head_extra;
|
|
struct jffs_fm *tail_extra;
|
|
struct mutex biglock;
|
|
};
|
|
|
|
/* Notice the two members head_extra and tail_extra in the jffs_control
|
|
structure above. Those are only used during the scanning of the flash
|
|
memory; while the file system is being built. If the data in the flash
|
|
memory is organized like
|
|
|
|
+----------------+------------------+----------------+
|
|
| USED / DIRTY | FREE | USED / DIRTY |
|
|
+----------------+------------------+----------------+
|
|
|
|
then the scan is split in two parts. The first scanned part of the
|
|
flash memory is organized through the members head and tail. The
|
|
second scanned part is organized with head_extra and tail_extra. When
|
|
the scan is completed, the two lists are merged together. The jffs_fm
|
|
struct that head_extra references is the logical beginning of the
|
|
flash memory so it will be referenced by the head member. */
|
|
|
|
|
|
|
|
struct jffs_fmcontrol *jffs_build_begin(struct jffs_control *c, int unit);
|
|
void jffs_build_end(struct jffs_fmcontrol *fmc);
|
|
void jffs_cleanup_fmcontrol(struct jffs_fmcontrol *fmc);
|
|
|
|
int jffs_fmalloc(struct jffs_fmcontrol *fmc, __u32 size,
|
|
struct jffs_node *node, struct jffs_fm **result);
|
|
int jffs_fmfree(struct jffs_fmcontrol *fmc, struct jffs_fm *fm,
|
|
struct jffs_node *node);
|
|
|
|
__u32 jffs_free_size1(struct jffs_fmcontrol *fmc);
|
|
__u32 jffs_free_size2(struct jffs_fmcontrol *fmc);
|
|
void jffs_sync_erase(struct jffs_fmcontrol *fmc, int erased_size);
|
|
struct jffs_fm *jffs_cut_node(struct jffs_fmcontrol *fmc, __u32 size);
|
|
struct jffs_node *jffs_get_oldest_node(struct jffs_fmcontrol *fmc);
|
|
long jffs_erasable_size(struct jffs_fmcontrol *fmc);
|
|
struct jffs_fm *jffs_fmalloced(struct jffs_fmcontrol *fmc, __u32 offset,
|
|
__u32 size, struct jffs_node *node);
|
|
int jffs_add_node(struct jffs_node *node);
|
|
void jffs_fmfree_partly(struct jffs_fmcontrol *fmc, struct jffs_fm *fm,
|
|
__u32 size);
|
|
|
|
#if CONFIG_JFFS_FS_VERBOSE > 0
|
|
void jffs_print_fmcontrol(struct jffs_fmcontrol *fmc);
|
|
#endif
|
|
#if 0
|
|
void jffs_print_node_ref(struct jffs_node_ref *ref);
|
|
#endif /* 0 */
|
|
|
|
#endif /* __LINUX_JFFS_FM_H__ */
|