A toy filesystem based on FUSE

supported operations:

• create
• mknod
• open
• release
• unlink
• mkdir
• opendir
• readdir
• rmdir
• releasedir
• read
• write
• lookup
• getattr
• setattr

NOTE: This is not fully POSIX compliant, as fully implementing POSIX semantics is tedious and complex

How to use

format

$ cargo run --bin mkfs /tmp/meta /tmp/data                                                                                           0 [12:12:58]
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.02s
     Running `target/debug/mkfs /tmp/meta /tmp/data`
formated meta_path => /tmp/meta store_path => /tmp/data

mount to ~/jfs

$ mkdir ~/jfs
$ cargo run --bin junkfs /tmp/meta ~/jfs                                                                                             0 [12:13:35]
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.02s
     Running `target/debug/junkfs /tmp/meta /home/abby/jfs`
log write to /tmp/junkfs.log

in other terminal

$ cat > x.c                                                                                                                          0 [12:14:06]
#include <stdio.h>

int main() {
        printf("hello world!\n");
}
$ cc x.c
$ ./a.out                                                                                                                            0 [12:14:50]
hello world!
$ stat a.out                                                                                                                         0 [12:14:52]
  File: a.out
  Size: 19832           Blocks: 1          IO Block: 4096   regular file
Device: 0,42    Inode: 3           Links: 1
Access: (0755/-rwxr-xr-x)  Uid: ( 1000/    abby)   Gid: ( 1000/    abby)
Access: 2024-06-02 12:14:50.000000000 +0800
Modify: 2024-06-02 12:14:50.000000000 +0800
Change: 2024-06-02 12:14:50.000000000 +0800
 Birth: -
$ stat x.c                                                                                                                           0 [12:14:56]
  File: x.c
  Size: 62              Blocks: 1          IO Block: 4096   regular file
Device: 0,42    Inode: 2           Links: 1
Access: (0644/-rw-r--r--)  Uid: ( 1000/    abby)   Gid: ( 1000/    abby)
Access: 2024-06-02 12:14:26.000000000 +0800
Modify: 2024-06-02 12:14:26.000000000 +0800
Change: 2024-06-02 12:14:26.000000000 +0800
 Birth: -
$ ls -li                                                                                                                             0 [12:19:18]
total 1
3 -rwxr-xr-x 1 abby abby 19832 Jun  2 12:14 a.out*
2 -rw-r--r-- 1 abby abby    62 Jun  2 12:14 x.c

umount, also notify junkfs to quit

$ umount ~/jfs

TODO

• du support
• file lock and concurrency support
• remote MetaData and File storage