jffs2文件系统使用

jffs2文件系统使用

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参考

u-boot增加对jffs2分区的识别与加载
u-boot访问jffs2文件系统
JFFS2 文件系统及新特性介绍
Uboot对jffs2的支持
JFFS2文件系统挂载过程优化的分析报告
AR# 71439 2017.1-2018.2: Zynq UltraScale+ MPSoC: Linux kernel panic for JFFS2 filesystem on POR or reboot
AR# 71114 2017.1-2018.2 Zynq UltraScale+ MPSoC: Linux kernel boot failed while mounting a JFFS2 filesystem in QSPI boot mode
在Linux PC上挂载JFFS2文件系统
jffs2文件系统镜像挂载到Ubuntu
ubuntu下挂载jffs2文件系统

uboot

uboot打开宏支持，

#define CONFIG_CMD_JFFS2/*modify by zhuce*/
#define CONFIG_MTD_DEVICE
#define CONFIG_MTD_PARTITIONS
#define CONFIG_CMD_MTDPARTS
#define CONFIG_FLASH_CFI_MTD

在FreeScale T2080的u-boot下，编译错误，更改jffs2.c的命令列表，

cmd/jffs2.o:(.u_boot_list_2_cmd_2_ls+0x0): multiple definition of `_u_boot_list_2_cmd_2_ls'
cmd/fs.o:(.u_boot_list_2_cmd_2_ls+0x0): first defined here
scripts/Makefile.build:359: recipe for target 'cmd/built-in.o' failed
make[1]: *** [cmd/built-in.o] Error 1
Makefile:1223: recipe for target 'cmd' failed
make: *** [cmd] Error 2

更改环境变量，

partition=nor0,0
mtdids=nor0&#
mtdparts=mtdparts&#:768k(boot),128k@7f00000(fman),-(user)

-(user)的-表示剩余空间，jffs2.c官方的环境变量介绍，

/** Three environment variables are used by the parsing routines:** 'partition' - keeps current partition identifier** partition  := <part-id>* <part-id>  := <dev-id>,part_num*** 'mtdids' - linux kernel mtd device id <-> u-boot device id mapping** mtdids=<idmap>[,<idmap>,...]** <idmap>    := <dev-id>=<mtd-id>* <dev-id>   := 'nand'|'nor'|'onenand'<dev-num>* <dev-num>  := mtd device number, 0...* <mtd-id>   := unique device tag used by linux kernel to find mtd device (mtd->name)*** 'mtdparts' - partition list** mtdparts=mtdparts=<mtd-def>[;<mtd-def>...]** <mtd-def>  := <mtd-id>:<part-def>[,<part-def>...]* <mtd-id>   := unique device tag used by linux kernel to find mtd device (mtd->name)* <part-def> := <size>[@<offset>][<name>][<ro-flag>]* <size>     := standard linux memsize OR '-' to denote all remaining space* <offset>   := partition start offset within the device* <name>     := '(' NAME ')'* <ro-flag>  := when set to 'ro' makes partition read-only (not used, passed to kernel)** Notes:* - each <mtd-id> used in mtdparts must albo exist in 'mtddis' mapping* - if the above variables are not set defaults for a given target are used** Examples:** 1 NOR Flash, with 1 single writable partition:* mtdids=nor0=edb7312-nor* mtdparts=mtdparts=edb7312-nor:-** 1 NOR Flash with 2 partitions, 1 NAND with one* mtdids=nor0=edb7312-nor,nand0=edb7312-nand* mtdparts=mtdparts=edb7312-nor:256k(ARMboot)ro,-(root);edb7312-nand:-(home)**/

u-boot下切换分区，查看分区命令，

T2080> chpart nor0,1
partition changed to nor0,1
T2080> mtdpartsdevice nor0 &>, # parts = 7#: name                size            offset          mask_flags0: rcw                 0x00020000      0x00000000      01: fs                  0x0f5e0000      0x00020000      02: dtb                 0x00020000      0x0f600000      03: kernel              0x008e0000      0x0f620000      04: fman                0x00020000      0x0ff00000      05: bootenv             0x00020000      0x0ff20000      06: boot                0x000c0000      0x0ff40000      0active partition: nor0,1 - (fs) 0x0f5e0000 @ 0x00020000defaults:
mtdids  : nor0&#
mtdparts: mtdparts&#:128k(rcw),251776k(fs),128k(dtb),9088k(kernel),128k(fman),128k(bootenv),768k(boot)

jffs2相关命令，

T2080> jffs2info
### filesystem type is JFFS2
Scanning JFFS2 FS: ................................... done.
Compression: NONEfrag count: 1522compressed sum: 379035uncompressed sum: 379035
Compression: ZEROfrag count: 0compressed sum: 0uncompressed sum: 0
Compression: RTIMEfrag count: 11compressed sum: 68uncompressed sum: 174
Compression: RUBINMIPSfrag count: 0compressed sum: 0uncompressed sum: 0
Compression: COPYfrag count: 0compressed sum: 0uncompressed sum: 0
Compression: DYNRUBINfrag count: 0compressed sum: 0uncompressed sum: 0
Compression: ZLIBfrag count: 32260compressed sum: 52613058uncompressed sum: 126003035
T2080> jffs2lsdrwxr-xr-x        0 Wed Mar 13 07:24:22 2019 bindrwxr-xr-x        0 Sat Mar 17 13:20:29 2018 bootdrwxr-xr-x        0 Sat Mar 17 13:20:29 2018 devdrwxr-xr-x        0 Wed Mar 13 07:24:27 2019 etcdrwxr-xr-x        0 Sat Mar 17 13:20:29 2018 homedrwxr-xr-x        0 Wed Mar 21 07:24:15 2018 libdrwxr-xr-x        0 Wed Mar 13 07:24:27 2019 lib64lrwxrwxrwx       12 Wed Mar 21 07:23:37 2018 linuxrc -> /bin/busyboxdrwx------        0 Wed Mar 21 07:24:22 2018 lost+founddrwxr-xr-x        0 Sat Mar 17 13:20:29 2018 mediadrwxr-xr-x        0 Sat Mar 17 13:20:29 2018 mntdrwxr-xr-x        0 Sat Mar 17 13:20:29 2018 procdrwxr-xr-x        0 Wed Mar 21 07:24:11 2018 rootdrwxr-xr-x        0 Sat Mar 17 13:20:29 2018 rundrwxr-xr-x        0 Wed Mar 21 07:24:15 2018 sbindrwxr-xr-x        0 Sat Mar 17 13:20:29 2018 sysdrwxrwxrwt        0 Sat Mar 17 13:20:29 2018 tmpdrwxr-xr-x        0 Sat Mar 17 13:43:18 2018 usrdrwxr-xr-x        0 Wed Mar 21 07:24:15 2018 var

制作jffs2镜像

$ sudo apt install mtd-utils
# 没有网，离线装[mtd-utils](/+source/mtd-utils)，
$ sudo dpkg -i /mnt/hgfs/F/mtd-utils_1.5.2-1_amd64.deb
$ mkfs.jffs2 -h
Make a JFFS2 file system image from an existing directory treeOptions:-p, --pad[=SIZE]        Pad output to SIZE bytes with 0xFF. If SIZE isnot specified, the output is padded to the end ofthe final erase block-r, -d, --root=DIR      Build file system from directory DIR (default: cwd)-s, --pagesize=SIZE     Use page size (max data node size) SIZE.Set according to target system's memory managementpage size (default: 4KiB)-e, --eraseblock=SIZE   Use erase block size SIZE (default: 64KiB)-c, --cleanmarker=SIZE  Size of cleanmarker (default 12)-m, --compr-mode=MODE   Select compression mode (default: priority)-x, --disable-compressor=COMPRESSOR_NAMEDisable a compressor-X, --enable-compressor=COMPRESSOR_NAMEEnable a compressor-y, --compressor-priority=PRIORITY:COMPRESSOR_NAMESet the priority of a compressor-L, --list-compressors  Show the list of the available compressors-t, --test-compression  Call decompress and compare with the original (for test)-n, --no-cleanmarkers   Don't add a cleanmarker to every eraseblock-o, --output=FILE       Output to FILE (default: stdout)-l, --little-endian     Create a little-endian filesystem-b, --big-endian        Create a big-endian filesystem-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       Squash owners making all files be owned by root-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              Display this help text-v, --verbose           Verbose operation-V, --version           Display version information-i, --incremental=FILE  Parse FILE and generate appendage output for it
$ sumtool -h
sumtool: error!: Usage: sumtool [OPTIONS] -i inputfile -o outputfileConvert the input JFFS2 image to a summarized JFFS2 image
Summary makes mounting faster - if summary support enabled in your kernelOptions:-e, --eraseblock=SIZE     Use erase block size SIZE (default: 64KiB)(usually 16KiB on NAND)-c, --cleanmarker=SIZE    Size of cleanmarker (default 12).(usually 16 bytes on NAND, and will be set tothis value if left at the default 12). Will bestored in OOB after each physical page composinga physical eraseblock.-n, --no-cleanmarkers     Don't add a cleanmarker to every eraseblock-o, --output=FILE         Output to FILE -i, --input=FILE          Input from FILE -b, --bigendian           Image is big endian-l  --littleendian        Image is little endian-h, --help                Display this help text-v, --verbose             Verbose operation-V, --version             Display version information-p, --pad                 Pad the OUTPUT with 0xFF to the end of the finaleraseblock

其中-s指定Page size，这里是系统的Page，不是Flash的Page，

$ mkfs.jffs2 -n -e 0x20000 -p 0x3200000 -d rootfs/ -o rootfs.jffs2
$ sumtool -n -e 0x20000 -p -i rootfs.jffs2 -o rootfs.jffs2.sum$ mkfs.jffs2 -b -n -e 0x20000 -p 0x3200000 -d rootfs/ -o rootfs.jffs2
$ sumtool -b -n -e 0x20000 -p -i rootfs.jffs2 -o rootfs.jffs2.sum

从jffs2启动，

bootargs=rootfstype=jffs2 noinitrd root=/dev/mtdblock1 rw console=ttyS0,115200

PC挂载jffs2

使用sudo ./jffs2_mount_mtdram.sh mtd7 ./jffs2 256，

$ cat jffs2_mount_mtdram.sh 
#!/bin/bash## Script to mount jffs2 filesystem using mtd kernel modules.
## EMAC, Inc. 2009if [[ $# -lt 2 ]]
thenecho "Usage: $0 FSNAME.JFFS2 MOUNTPOINT [ERASEBLOCK_SIZE]"exit 1
fiif [ "$(whoami)" != "root" ]
thenecho "$0 must be run as root!"exit 1
fiif [[ ! -e $1 ]]
thenecho "$1 does not exist"exit 1
fiif [[ ! -d $2 ]]
thenecho "$2 is not a valid mount point"exit 1
fiif [[ "$3" == "" ]]
thenesize="128"
elseesize="$3"
fi# cleanup if necessary
umount /dev/mtdblock0 &>/dev/null
modprobe -r mtdram &>/dev/null
modprobe -r mtdblock &>/dev/nullmodprobe mtdram total_size=32768 erase_size=$esize || exit 1
modprobe mtdblock || exit 1
dd if="$1" of=/dev/mtdblock0 || exit 1
mount -t jffs2 /dev/mtdblock0 $2 || exit 1echo "Successfully mounted $1 on $2"
exit 0

问题

操作小文件（两行字符串）之后，重启输出，再次重启，不输出错误，

jffs2: Empty flash at 0x036f2358 ends at 0x036f239c
jffs2: Empty flash at 0x036f23cc ends at 0x036f2400
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f2404: 0x0600 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f2408: 0x998a instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f240c: 0x0e7d instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f2410: 0x785e instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f2414: 0x596f instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f2418: 0x0cf6 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f241c: 0xa31f instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f2420: 0x063b instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f2424: 0xcfad instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x036f2428: 0xb1db instead
jffs2: Further such events for this erase block will not be printed

操作大文件（8MB）之后，该问题是我的设备树配置错误。

root@t2080rdb:/boot# ls -l
jffs2: notice: (1745) jffs2_get_inode_nodes: Node header CRC failed at 0x4878630. {ffff,ffff,ffffffff,ffffffff}
jffs2: notice: (1745) jffs2_get_inode_nodes: Node header CRC failed at 0x485e108. {ffff,ffff,ffffffff,ffffffff}
jffs2: notice: (1745) jffs2_get_inode_nodes: Node header CRC failed at 0x484dcb0. {ffff,ffff,ffffffff,ffffffff}

下面问题是mkfs时参数设置错误，

fs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f6024: 0x858b instead
[   40.543687] jffs2: Further such events for this erase block will not be printed
[   40.554010] jffs2: Node at 0x000f6c80 with length 0x00000b40 would run over the end of the erase block
[   40.566171] jffs2: Perhaps the file system was created with the wrong erase size?
[   40.576693] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f7000: 0x61e3 instead
[   40.589138] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f7004: 0x5ce6 instead
[   40.601580] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f7008: 0x669e instead
[   40.614016] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f700c: 0xad53 instead
[   40.626457] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f7010: 0x05ab instead
[   40.638897] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f7014: 0x0cce instead
[   40.651335] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f7018: 0x26c1 instead
[   40.663772] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f701c: 0x887b instead
[   40.676211] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f7020: 0x5a36 instead
[   40.688603] jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x000f7024: 0xcf46 instead

开机打印，

[    4.849632] jffs2: notice: (1) jffs2_build_xattr_subsystem: complete building xattr subsystem, 0 of xdatum (0 unchecked, 0 orphan) and 0 of xref (0 dead, 0 orphan) found.