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xiuos/Ubiquitous/XiZi_AIoT/services/fs/include/fs.h
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2024-01-31 10:30:34 +08:00

111 lines
3.1 KiB
C

/*
* Copyright (c) 2020 AIIT XUOS Lab
* XiUOS is licensed under Mulan PSL v2.
* You can use this software according to the terms and conditions of the Mulan PSL v2.
* You may obtain a copy of Mulan PSL v2 at:
* http://license.coscl.org.cn/MulanPSL2
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
* See the Mulan PSL v2 for more details.
*/
#pragma once
#include <stdint.h>
#include "block_io.h"
// memory file system memlayout.
// [ block 0 ] [ block 1 ] [block 2] [...] [ block 28 ] [ ... ]
// [ unused ] [super block] [Inode bit map] [block bit map] [data blocks]
#define NR_DIRECT_BLOCKS 5 // direct block number
#define NR_INDIRECT_BLOCKS 8 // indirect block number
#define ROOT_INUM 1 // root inode number
#define MAX_INDIRECT_BLOCKS (BLOCK_SIZE / sizeof(uint32_t)) // Mmaximum number of indirect blocks mapped per block
#define MAX_FILE_SIZE (NR_DIRECT_BLOCKS + (NR_INDIRECT_BLOCKS * MAX_INDIRECT_BLOCKS)) // maximum size of a file
// memory fs range
struct MemFsRange {
uintptr_t memfs_start;
uint32_t memfs_nr_blocks;
};
// current state of the Inode
enum INODE_STATE {
I_RESERVED = 0,
I_BUSY,
I_VALID
};
// memfs file type
enum FILE_TYPE {
T_RESERVED = 0,
T_DIR, // Directory
T_FILE, // File
T_DEV, // Device
};
// File system super block
struct SuperBlock {
uint32_t size; // Number of total blocks of file system image
uint32_t nblocks; // Number of data blocks
uint32_t ninodes; // Number of inodes.
};
// state of the Inode
struct State {
short type; // Type of file
int dev; // File system's disk device
uint32_t ino; // Inode number
short nlink; // Number of links to file
uint32_t size; // Size of file in bytes
};
// Inode structure
struct Inode {
uint32_t inum; // Inode number
short type; // File type
short nlink; // Number of links to Inode in file system
uint32_t size; // Size of file (bytes)
uint32_t addrs[NR_DIRECT_BLOCKS + NR_INDIRECT_BLOCKS]; // Data block addresses
};
// directory entry
#define DIR_NAME_SIZE 14
struct DirectEntry {
uint16_t inum;
char name[DIR_NAME_SIZE];
};
// file descriptor definition
#define MAX_PATH_LEN 128
struct FileDescriptor {
char path[MAX_PATH_LEN];
void* data;
struct State st;
};
// range of memory fs
extern struct MemFsRange MemFsRange;
void MemFsInit(uintptr_t _binary_fs_img_start, uint32_t fs_img_len);
void ReadSuperBlock(struct SuperBlock*);
// fs Inode ops
struct Inode* InodeGet(uint32_t inum);
struct Inode* InodeCreate(struct Inode*, char*, short, short, short);
int InodeDelete(struct Inode*, char*);
int InodeRead(struct Inode*, char*, int, int);
int InodeWrite(struct Inode*, char*, uint32_t, uint32_t);
struct Inode* InodeSeek(struct Inode*, char*);
struct Inode* InodeParentSeek(struct Inode*, char*, char*);
void InodeStateGet(struct Inode*, struct State*);
// fs fd ops
struct FileDescriptor* GetFileDescriptor(int fd);
void FreeFileDescriptor(int fd);
int AllocFileDescriptor(void);