问题描述：
RK3399开发板烧录官网提供的ubuntu镜像： Ubuntu 16.04 Server arm64（下载地址：https://www.96boards.org/documentation/consumer/rock/downloads/ubuntu.md.html）,
开发板上电运行查看系统根目录容量已使用96%：
root@rock960:~# df Filesystem 1K-blocks Used Available Use% Mounted on /dev/root 1515376 1353320 67032 96% / devtmpfs 1951660 0 1951660 0% /dev tmpfs 1952236 0 1952236 0% /dev/shm tmpfs 1952236 49692 1902544 3% /run tmpfs 5120 0 5120 0% /run/lock tmpfs 1952236 0 1952236 0% /sys/fs/cgroup tmpfs 390448 0 390448 0% /run/user/0 root@rock960:~#
再查看磁盘容量，32GB eMMC实际可用容量29GB，除去已分区容量还有27.5GB容量未分区：
root@rock960:~# fdisk -l /dev/mmcblk1 Disk /dev/mmcblk1: 29.1 GiB, 31268536320 bytes, 61071360 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: F464C417-6F1F-4BF8-A1CE-BDB432A3BD1B Device Start End Sectors Size Type /dev/mmcblk1p1 64 8063 8000 3.9M Linux filesystem /dev/mmcblk1p2 16384 24575 8192 4M Linux filesystem /dev/mmcblk1p3 24576 32767 8192 4M Linux filesystem /dev/mmcblk1p4 32768 262143 229376 112M EFI System /dev/mmcblk1p5 262144 3409886 3147743 1.5G Linux filesystem root@rock960:~#
因此需要把未分区的27.5GB磁盘空间追加到/dev/mmcblk1p5并扩容rootfs文件系统。解决方法主要用到两个命令：parted和resize2fs。
首先重新分配/dev/mmcblk1p5分区大小到覆盖整个磁盘剩余容量：（注意fdisk不支持GPT分区）
root@rock960:~# parted /dev/mmcblk1 GNU Parted 3.2 Using /dev/mmcblk1 Welcome to GNU Parted! Type 'help' to view a list of commands. (parted) print Model: MMC BJNB4R (sd/mmc) Disk /dev/mmcblk1: 31.3GB Sector size (logical/physical): 512B/512B Partition Table: gpt Disk Flags: Number Start End Size File system Name Flags 1 32.8kB 4129kB 4096kB loader1 2 8389kB 12.6MB 4194kB loader2 3 12.6MB 16.8MB 4194kB trust 4 16.8MB 134MB 117MB fat16 boot boot, esp 5 134MB 1746MB 1612MB ext4 rootfs (parted) unit s (parted) print Model: MMC BJNB4R (sd/mmc) Disk /dev/mmcblk1: 61071360s Sector size (logical/physical): 512B/512B Partition Table: gpt Disk Flags: Number Start End Size File system Name Flags 1 64s 8063s 8000s loader1 2 16384s 24575s 8192s loader2 3 24576s 32767s 8192s trust 4 32768s 262143s 229376s fat16 boot boot, esp 5 262144s 3409886s 3147743s ext4 rootfs (parted) resizepart 5 100% (parted) print Model: MMC BJNB4R (sd/mmc) Disk /dev/mmcblk1: 61071360s Sector size (logical/physical): 512B/512B Partition Table: gpt Disk Flags: Number Start End Size File system Name Flags 1 64s 8063s 8000s loader1 2 16384s 24575s 8192s loader2 3 24576s 32767s 8192s trust 4 32768s 262143s 229376s fat16 boot boot, esp 5 262144s 61071326s 60809183s ext4 rootfs (parted) Q root@rock960:~#
然后进行EXT文件系统扩容：
root@rock960:~# resize2fs /dev/mmcblk1p5 resize2fs 1.42.13 (17-May-2015) The filesystem is already 7601147 (4k) blocks long. Nothing to do! root@rock960:~#
这时查看根目录下已使用容量已经变成5%
root@rock960:~# df -TH Filesystem Type Size Used Avail Use% Mounted on /dev/root ext4 31G 1.4G 28G 5% / devtmpfs devtmpfs 2.0G 0 2.0G 0% /dev tmpfs tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs tmpfs 2.0G 51M 2.0G 3% /run tmpfs tmpfs 5.3M 0 5.3M 0% /run/lock tmpfs tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup tmpfs tmpfs 400M 0 400M 0% /run/user/0 root@rock960:~#
后续：
TBD