| /* | |
| * JFFS -- Journalling 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.h,v 1.20 2001/09/18 21:33:37 dwmw2 Exp $ | |
| * | |
| * Ported to Linux 2.3.x and MTD: | |
| * Copyright (C) 2000 Alexander Larsson (alex@cendio.se), Cendio Systems AB | |
| * | |
| */ | |
| #ifndef __LINUX_JFFS_H__ | |
| #define __LINUX_JFFS_H__ | |
| #include <linux/types.h> | |
| #include <linux/completion.h> | |
| #define JFFS_VERSION_STRING "1.0" | |
| /* This is a magic number that is used as an identification number for | |
| this file system. It is written to the super_block structure. */ | |
| #define JFFS_MAGIC_SB_BITMASK 0x07c0 /* 1984 */ | |
| /* This is a magic number that every on-flash raw inode begins with. */ | |
| #define JFFS_MAGIC_BITMASK 0x34383931 /* "1984" */ | |
| /* These two bitmasks are the valid ones for the flash memories we have | |
| for the moment. */ | |
| #define JFFS_EMPTY_BITMASK 0xffffffff | |
| #define JFFS_DIRTY_BITMASK 0x00000000 | |
| /* This is the inode number of the root node. */ | |
| #define JFFS_MIN_INO 1 | |
| /* How many slots in the file hash table should we have? */ | |
| #define JFFS_HASH_SIZE 40 | |
| /* Don't use more than 254 bytes as the maximum allowed length of a file's | |
| name due to errors that could occur during the scanning of the flash | |
| memory. In fact, a name length of 255 or 0xff, could be the result of | |
| an uncompleted write. For instance, if a raw inode is written to the | |
| flash memory and there is a power lossage just before the length of | |
| the name is written, the length 255 would be interpreted as an illegal | |
| value. */ | |
| #define JFFS_MAX_NAME_LEN 254 | |
| /* Commands for ioctl(). */ | |
| #define JFFS_IOCTL_MAGIC 't' | |
| #define JFFS_PRINT_HASH _IO(JFFS_IOCTL_MAGIC, 90) | |
| #define JFFS_PRINT_TREE _IO(JFFS_IOCTL_MAGIC, 91) | |
| #define JFFS_GET_STATUS _IO(JFFS_IOCTL_MAGIC, 92) | |
| /* XXX: This is something that we should try to get rid of in the future. */ | |
| #define JFFS_MODIFY_INODE 0x01 | |
| #define JFFS_MODIFY_NAME 0x02 | |
| #define JFFS_MODIFY_DATA 0x04 | |
| #define JFFS_MODIFY_EXIST 0x08 | |
| struct jffs_control; | |
| /* The JFFS raw inode structure: Used for storage on physical media. */ | |
| /* Perhaps the uid, gid, atime, mtime and ctime members should have | |
| more space due to future changes in the Linux kernel. Anyhow, since | |
| a user of this filesystem probably have to fix a large number of | |
| other things, we have decided to not be forward compatible. */ | |
| struct jffs_raw_inode | |
| { | |
| __u32 magic; /* A constant magic number. */ | |
| __u32 ino; /* Inode number. */ | |
| __u32 pino; /* Parent's inode number. */ | |
| __u32 version; /* Version number. */ | |
| __u32 mode; /* The file's type or mode. */ | |
| __u16 uid; /* The file's owner. */ | |
| __u16 gid; /* The file's group. */ | |
| __u32 atime; /* Last access time. */ | |
| __u32 mtime; /* Last modification time. */ | |
| __u32 ctime; /* Creation time. */ | |
| __u32 offset; /* Where to begin to write. */ | |
| __u32 dsize; /* Size of the node's data. */ | |
| __u32 rsize; /* How much are going to be replaced? */ | |
| __u8 nsize; /* Name length. */ | |
| __u8 nlink; /* Number of links. */ | |
| __u8 spare : 6; /* For future use. */ | |
| __u8 rename : 1; /* Rename to a name of an already existing file? */ | |
| __u8 deleted : 1; /* Has this file been deleted? */ | |
| __u8 accurate; /* The inode is obsolete if accurate == 0. */ | |
| __u32 dchksum; /* Checksum for the data. */ | |
| __u16 nchksum; /* Checksum for the name. */ | |
| __u16 chksum; /* Checksum for the raw inode. */ | |
| }; | |
| /* Define the offset of the accurate byte in struct jffs_raw_inode. */ | |
| #define JFFS_RAW_INODE_ACCURATE_OFFSET (sizeof(struct jffs_raw_inode) \ | |
| - 2 * sizeof(__u32) - sizeof(__u8)) | |
| /* Define the offset of the chksum member in struct jffs_raw_inode. */ | |
| #define JFFS_RAW_INODE_CHKSUM_OFFSET (sizeof(struct jffs_raw_inode) \ | |
| - sizeof(__u16)) | |
| /* Define the offset of the dchksum member in struct jffs_raw_inode. */ | |
| #define JFFS_RAW_INODE_DCHKSUM_OFFSET (sizeof(struct jffs_raw_inode) \ | |
| - sizeof(__u16) - sizeof(__u16) \ | |
| - sizeof(__u32)) | |
| /* The RAM representation of the node. The names of pointers to | |
| jffs_nodes are very often just called `n' in the source code. */ | |
| struct jffs_node | |
| { | |
| __u32 ino; /* Inode number. */ | |
| __u32 version; /* Version number. */ | |
| __u32 data_offset; /* Logic location of the data to insert. */ | |
| __u32 data_size; /* The amount of data this node inserts. */ | |
| __u32 removed_size; /* The amount of data that this node removes. */ | |
| __u32 fm_offset; /* Physical location of the data in the actual | |
| flash memory data chunk. */ | |
| __u8 name_size; /* Size of the name. */ | |
| struct jffs_fm *fm; /* Physical memory information. */ | |
| struct jffs_node *version_prev; | |
| struct jffs_node *version_next; | |
| struct jffs_node *range_prev; | |
| struct jffs_node *range_next; | |
| }; | |
| /* The RAM representation of a file (plain files, directories, | |
| links, etc.). Pointers to jffs_files are normally named `f' | |
| in the JFFS source code. */ | |
| struct jffs_file | |
| { | |
| __u32 ino; /* Inode number. */ | |
| __u32 pino; /* Parent's inode number. */ | |
| __u32 mode; /* file_type, mode */ | |
| __u16 uid; /* owner */ | |
| __u16 gid; /* group */ | |
| __u32 atime; /* Last access time. */ | |
| __u32 mtime; /* Last modification time. */ | |
| __u32 ctime; /* Creation time. */ | |
| __u8 nsize; /* Name length. */ | |
| __u8 nlink; /* Number of links. */ | |
| __u8 deleted; /* Has this file been deleted? */ | |
| char *name; /* The name of this file; NULL-terminated. */ | |
| __u32 size; /* The total size of the file's data. */ | |
| __u32 highest_version; /* The highest version number of this file. */ | |
| struct jffs_control *c; | |
| struct jffs_file *parent; /* Reference to the parent directory. */ | |
| struct jffs_file *children; /* Always NULL for plain files. */ | |
| struct jffs_file *sibling_prev; /* Siblings in the same directory. */ | |
| struct jffs_file *sibling_next; | |
| struct list_head hash; /* hash list. */ | |
| struct jffs_node *range_head; /* The final data. */ | |
| struct jffs_node *range_tail; /* The first data. */ | |
| struct jffs_node *version_head; /* The youngest node. */ | |
| struct jffs_node *version_tail; /* The oldest node. */ | |
| }; | |
| /* This is just a definition of a simple list used for keeping track of | |
| files deleted due to a rename. This list is only used during the | |
| mounting of the file system and only if there have been rename operations | |
| earlier. */ | |
| struct jffs_delete_list | |
| { | |
| __u32 ino; | |
| struct jffs_delete_list *next; | |
| }; | |
| /* A struct for the overall file system control. Pointers to | |
| jffs_control structs are named `c' in the source code. */ | |
| struct jffs_control | |
| { | |
| struct super_block *sb; /* Reference to the VFS super block. */ | |
| struct jffs_file *root; /* The root directory file. */ | |
| struct list_head *hash; /* Hash table for finding files by ino. */ | |
| struct jffs_fmcontrol *fmc; /* Flash memory control structure. */ | |
| __u32 hash_len; /* The size of the hash table. */ | |
| __u32 next_ino; /* Next inode number to use for new files. */ | |
| __u16 building_fs; /* Is the file system being built right now? */ | |
| struct jffs_delete_list *delete_list; /* Track deleted files. */ | |
| pid_t thread_pid; /* GC thread's PID */ | |
| struct task_struct *gc_task; /* GC task struct */ | |
| struct completion gc_thread_comp; /* GC thread exit mutex */ | |
| __u32 gc_minfree_threshold; /* GC trigger thresholds */ | |
| __u32 gc_maxdirty_threshold; | |
| }; | |
| /* Used to inform about flash status. */ | |
| struct jffs_flash_status | |
| { | |
| __u32 size; | |
| __u32 used; | |
| __u32 dirty; | |
| __u32 begin; | |
| __u32 end; | |
| }; | |
| /* This stuff could be used for finding memory leaks. */ | |
| #define JFFS_MEMORY_DEBUG 0 | |
| extern long no_jffs_node; | |
| #if defined(JFFS_MEMORY_DEBUG) && JFFS_MEMORY_DEBUG | |
| extern long no_jffs_control; | |
| extern long no_jffs_raw_inode; | |
| extern long no_jffs_node_ref; | |
| extern long no_jffs_fm; | |
| extern long no_jffs_fmcontrol; | |
| extern long no_hash; | |
| extern long no_name; | |
| #define DJM(x) x | |
| #else | |
| #define DJM(x) | |
| #endif | |
| #endif /* __LINUX_JFFS_H__ */ |