partfs

FUSE-based file system for accessing partitions on a disk

Building

Run make at the top level.

Your system will need to have:

cmake
libfdisk (libraries and development headers)
libfuse (libraries and development headers)

On a Debian/Ubuntu system:

apt-get install cmake libfdisk1 libfdisk-dev libfuse2 libfuse-dev

About

partfs allows one to access partitions within a device or file. the main purpose of partfs is to allow the creation of disk images without superuser privileges. this can be useful for the enabling automatic partition discovery for containers or for building disk images for embedded software.

the mounted directory presents the partitions as files, allowing mkfs.* to be used to create file systems on the partitions

to create a disk image with a single bootable partition with an ext4 file system:

$ dd if=/dev/zero of=disk.image bs=1M count=4
4+0 records in
4+0 records out
4194304 bytes (4.2 MB, 4.0 MiB) copied, 0.00470867 s, 891 MB/s
$ parted --script disk.image \
    mktable msdos mkpart primary 2048s 100% set 1 boot on
$ mkdir mntdir
$ partfs -o dev=disk.image mntdir
$ mkfs.ext4 mntdir/p1
mke2fs 1.42.13 (17-May-2015)
Creating filesystem with 3072 1k blocks and 768 inodes

Allocating group tables: done
Writing inode tables: done
Creating journal (1024 blocks): done
Writing superblocks and filesystem accounting information: done

$ fusermount -u mntdir

to verify that the partition and file system were successfully created:

$ sudo kpartx -a -v disk.image
add map loop0p1 (253:0): 0 6144 linear 7:0 2048
$ sudo fsck.ext4 /dev/mapper/loop0p1
e2fsck 1.42.13 (17-May-2015)
/dev/mapper/loop0p1: clean, 11/768 files, 1150/3072 blocks
$ sudo kpartx -d disk.image
loop deleted : /dev/loop0