實例：mkfs.jffs2 -r rootfs -o rootfs.jffs2 -e 0x4000 --pad=0x1000000 -s 0x200 -n

mkfs.jffs2: Usage: mkfs.jffs2 [OPTIONS]
Make a JFFS2 file system image from an existing directory tree
Options:
-p, --pad[=SIZE]?用16進制來表示所要輸出檔案的大小，也就是root.jffs2?很重要的是, 為了不浪費flash空間, 這個值最好符合flash driver所規劃的區塊大小。如果不足則使用0xff來填充補滿。
-r, -d, --root=DIR??????指定要做成image的源資料夾.(默認：當前文件夾)
-s, --pagesize=SIZE?????節點頁大小(默認: 4KiB)
-e, --eraseblock=SIZE???設定擦除塊的大小為(默認: 64KiB)
-c, --cleanmarker=SIZE Size of cleanmarker (default 12)
-m, --compr-mode=MODE???Select compression mode (default: priortiry)
-x, --disable-compressor=COMPRESSOR_NAME
??????????????????????????Disable a compressor
-X, --enable-compressor=COMPRESSOR_NAME
??????????????????????????Enable a compressor
-y, --compressor-priority=PRIORITY:COMPRESSOR_NAME
??????????????????????????Set the priority of a compressor
-L, --list-compressors Show the list of the avaiable compressors
-t, --test-compression Call decompress and compare with the original (for test)
-n, --no-cleanmarkers???指明不添加清楚標記（nand flash 有自己的校檢塊，存放相關的信息。）?????如果掛載后會出現類似：
?CLEANMARKER node found at 0x0042c000 has totlen 0xc != normal 0x0
??????????????????????????的警告，則加上-n 就會消失。
-o, --output=FILE???????指定輸出image檔案的文件名.(default: stdout)
-l, --little-endian?????指定使用小端格式
-b, --big-endian????????指定使用大端格式
-D, --devtable=FILE?????Use the named FILE as a device table file
-f, --faketime??????????Change all file times to '0' for regression testing
-q, --squash????????????Squash permissions and owners making all files be owned by root
-U, --squash-uids???????將所有文件的擁有者設為root用戶
-P, --squash-perms??????Squash permissions on all files
??????--with-xattr????????stuff all xattr entries into image
??????--with-selinux??????stuff only SELinux Labels into jffs2 image
??????--with-posix-acl????stuff only POSIX ACL entries into jffs2 image
-h, --help??????????????顯示這些文字
-v, --verbose???????????Verbose operation
-V, --version???????????顯示版本
-i, --incremental=FILE Parse FILE and generate appendage output for it