I'm using nilfs 2.0.15, slackware current, kernel 2.6.28, on Acer Aspire One model A101, which uses Atom CPU.
I failed to find the superblock towards the end of either mmcblk0 or mmcblk0p1, but a search of hex string 0200000000003434 reveals that: mmcblk0: starts at address 00400400, and the nilfs segment 0 starts at address 00401000. mmcblk0p1: starts at address 003FE400, and the nilfs segment 0 starts at 003FF000. I hope my SD card is not messing up itself by rearranging the blocks! Regards, Paul Liu On 11/4/09, Jan de Kruyf <[email protected]> wrote: > Hallo, > here we go again. As a matter of interest, what version of nilfs and what > distribution are you running? And what processor? > your endiannes confused me at first. > > glad you fixed your hexedit > > I have looked at some numbers in the superblock and they look ok. I do > wonder if you have the garbage collector running. > > now for the second superblock. Please pay attention to the exact place of > it. Because it is of vital > importance if it in in partition 1 or in the root of the disk. > > the first superblock sits as you observed in the root. The flags say amongst > others that it was unmounted cleanly but errors were detected. > > see nilfs2_fs.h - NILFS2 on-disk structures and common declarations. in the > distribution. > /** > * struct nilfs_super_block - structure of super block on disk > */ > struct nilfs_super_block { > .... > translates bit for bit to what you see written in the super block on disk. > > Here is an example from a partition of mine on how to discover the > superblock copy > it should read the same as the 1st but in your case it might not. > It is a leftshift - subtract 1 - right shift algorithm. > go in hexedit to the last data with ">" (shift .) > note the address of the last byte (the size of the partion) > in mine: > 6566B3F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ................ > or the status line might give it > the address of the copy is now at 6566A000 > i.e. 6566B has 1 subtracted from it and the 3 least significant digits have > been zeroed. > > so please dump yours, see if the algorithm works on the 1st part or on the > root or both, > so we know where it is. > And check if it is exactly the same as the first one you send me > "0000400 0002 0000 0000 3434 0100 0000 b209 5b31" > etc. > > the next thing to discover is where the start of (nilfs)segment 0 is. > I am not quite sure what is written in it, but the signature is quite > distinct. > This is what it looks on my machine: > > 00000FC0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ................ > 00000FD0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ................ > 00000FE0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ................ > 00000FF0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ................ > 00001000 C4 1B 47 5B 51 62 19 13 11 FA AF 1E 38 00 10 00 > ..G[Qb......8... > 00001010 FB CE 01 00 00 00 00 00 EE BD F1 4A 00 00 00 00 > ...........J.... > 00001020 00 08 00 00 00 00 00 00 FF 07 00 00 32 00 00 00 > ............2... > 00001030 A0 83 00 00 00 00 00 00 EE 0D 00 00 00 00 00 00 > ................ > 00001040 07 00 00 00 00 00 00 00 7B 00 00 00 7B 00 00 00 > ........{...{... > 00001050 EA 9E 07 00 00 00 00 00 F8 01 00 00 00 00 00 00 > ................ > 00001060 EB 9E 07 00 00 00 00 00 F9 01 00 00 00 00 00 00 > ................ > 00001070 EC 9E 07 00 00 00 00 00 FA 01 00 00 00 00 00 00 > ................ > 00001080 ED 9E 07 00 00 00 00 00 FB 01 00 00 00 00 00 00 > ................ > 00001090 EE 9E 07 00 00 00 00 00 FC 01 00 00 00 00 00 00 > ................ > 000010A0 EF 9E 07 00 00 00 00 00 FD 01 00 00 00 00 00 00 > ................ > 000010B0 F0 9E 07 00 00 00 00 00 FE 01 00 00 00 00 00 00 > ................ > 000010C0 F2 9E 07 00 00 00 00 00 FF 01 00 00 00 00 00 00 > ................ > 000010D0 F3 9E 07 00 00 00 00 00 00 02 00 00 00 00 00 00 > ................ > 000010E0 F4 9E 07 00 00 00 00 00 01 02 00 00 00 00 00 00 > ................ > 000010F0 F5 9E 07 00 00 00 00 00 02 02 00 00 00 00 00 00 > ................ > 00001100 F6 9E 07 00 00 00 00 00 03 02 00 00 00 00 00 00 > ................ > 00001110 F7 9E 07 00 00 00 00 00 04 02 00 00 00 00 00 00 > ................ > 00001120 F8 9E 07 00 00 00 00 00 05 02 00 00 00 00 00 00 > ................ > 00001130 F9 9E 07 00 00 00 00 00 06 02 00 00 00 00 00 00 > ................ > 00001140 FA 9E 07 00 00 00 00 00 07 02 00 00 00 00 00 00 > ................ > 00001150 FB 9E 07 00 00 00 00 00 08 02 00 00 00 00 00 00 > ................ > 00001160 FC 9E 07 00 00 00 00 00 09 02 00 00 00 00 00 00 > ................ > 00001170 FD 9E 07 00 00 00 00 00 0A 02 00 00 00 00 00 00 > ................ > 00001180 FE 9E 07 00 00 00 00 00 0B 02 00 00 00 00 00 00 > ................ > 00001190 FF 9E 07 00 00 00 00 00 0C 02 00 00 00 00 00 00 > ................ > 000011A0 00 9F 07 00 00 00 00 00 0D 02 00 00 00 00 00 00 > ................ > 000011B0 01 9F 07 00 00 00 00 00 0E 02 00 00 00 00 00 00 > ................ > 000011C0 02 9F 07 00 00 00 00 00 0F 02 00 00 00 00 00 00 > ................ > 000011D0 03 9F 07 00 00 00 00 00 10 02 00 00 00 00 00 00 > ................ > 000011E0 04 9F 07 00 00 00 00 00 11 02 00 00 00 00 00 00 > ................ > > Segment 0 starts at hex 1000 of a nilfs partition as you can see above and > carries on for quite a while like this. > > so have a look on your disk if it sits at 1000 of the root partition or at > 1000 of partition 1. > > Once we have these things sorted I would say that we are ready to plant the > _right_ superblock of the 2 > in the right place and see if the partition is recoqnized by nilfs. > Off course we will save the place where we are going to plant that block > first. > > And now back to the birthday party . . . . > > Cheers, > > Jan > > > > On Wed, Nov 4, 2009 at 4:23 AM, Paul L <[email protected]> wrote: > >> On 11/3/09, Jan de Kruyf <[email protected]> wrote: >> > 26 august 98: hexedit 0.9.5 release >> > september 2005: >> > - version 1.2.12 this is the one I am running. >> >> Ah, I must be using the wrong hexedit.. now I've installed the same one >> you >> use. >> >> > did I hear that you have always had /dev/mmcblk0p1 in fstab?? >> >> Yes. What I put there is: >> >> /dev/mmcblk0p1 /home nilfs2 defaults 1 1 >> >> > hd -n1536 /dev/mmcblk0 >part.start >> > hd -s8191 -n1536 /dev/mmcblk0 >part1.start >> > an to verify the last line: >> > hd -n1536 /dev/mmcblk0p1 >part1a.start >> >> Here is the output (I use hexdump instead of hd, hopefully they are the >> same) >> >> bash-3.1# cat part.start >> 0000000 0000 0000 0000 0000 0000 0000 0000 0000 >> * >> 00001b0 0000 0000 0000 0000 0696 6c22 0000 0100 >> 00001c0 0001 0383 ffd0 0010 0000 dff0 01eb 0000 >> 00001d0 0000 0000 0000 0000 0000 0000 0000 0000 >> * >> 00001f0 0000 0000 0000 0000 0000 0000 0000 aa55 >> 0000200 0000 0000 0000 0000 0000 0000 0000 0000 >> * >> 0000400 0002 0000 0000 3434 0100 0000 b209 5b31 >> 0000410 1183 794c 0002 0000 07af 0000 0000 0000 >> 0000420 0000 d780 0003 0000 0001 0000 0000 0000 >> 0000430 0800 0000 0005 0000 090b 000e 0000 0000 >> 0000440 0710 0035 0000 0000 8502 0008 0000 0000 >> 0000450 8800 000b 0000 0000 93c1 493c 0000 0000 >> 0000460 013f 4ae2 0000 0000 2a8f 4aef 0000 0000 >> 0000470 00a2 0032 0003 0001 93c1 493c 0000 0000 >> 0000480 4e00 00ed 0000 0000 0000 0000 000b 0000 >> 0000490 0080 0020 00c0 0010 ed2b 04f5 41cb ae48 >> 00004a0 7f8a 4849 71ec e7f5 0000 0000 0000 0000 >> 00004b0 0000 0000 0000 0000 0000 0000 0000 0000 >> * >> 0000600 >> bash-3.1# cat part1.start >> 0001fff 0000 0000 0000 0000 0000 0000 0000 0000 >> * >> 00025ff >> bash-3.1# cat part1a.start >> 0000000 0000 0000 0000 0000 0000 0000 0000 0000 >> * >> 0000600 >> >> Regards, >> Paul Liu >> >> > On Tue, Nov 3, 2009 at 9:48 PM, Paul L <[email protected]> wrote: >> > >> >> Thanks a lot for the instructions! I'm attaching the mbr and partition >> >> table with this email. >> >> >> >> I'm pretty sure I had 1 partition on the card, since my /etc/fstab >> >> mounts mmcblk0p1. >> >> >> >> I think something corrupted my disk first, and then what I've done to >> >> the disk after noticing the corruption: >> >> >> >> 1. fdisk, it says use "w" will correct the error, so I did. But then >> >> the one parition is gone. >> >> 2. fdisk again, create a single partition, then "w" >> >> >> >> My mistake was that I didn't create a backup copy of the MBR. A hard >> >> lesson learned :( >> >> >> >> Also, why is that my hexedit doesn't take the "-s" option? It's >> >> version 0.9.7, and can't edit bigger than 4.2GB. >> >> >> >> My SD card is A-DATA brand, class 6, and 16GB. >> >> >> >> I'm using Linux, and fdisk version (util-linux-ng 2.14.1) >> >> >> >> Regards, >> >> Paul Liu >> >> >> >> On 11/3/09, Jan de Kruyf <[email protected]> wrote: >> >> > hallo, >> >> > Almost sounds like you had only the root master-boot-record >> /dev/mmcblk0 >> >> > before and now you have added 1 main partition /dev/mmcblk0p1. >> >> > >> >> > If (and only if) that is the case we have to undo the the 1st >> partition >> >> > + >> >> > check that no nilfs is overwritten. >> >> > and I would have to urgently study fdisk to see exactly what it >> >> > writes >> >> when >> >> > and where. >> >> > The last time I did tricks like these is quit a few years ago. >> >> > >> >> > It is the Linux version of fdisk is it?? >> >> > >> >> > So here is the plan of action: >> >> > hexdump the master boot record to file. >> >> > like this: >> >> > >> >> > dd if=/dev/mmcblk0 of=backup-mmcblk0.mbr count=1 bs=512 >> >> > >> >> > then dump any partitions of the device in a format useful as input to >> >> > sfdisk. For example, >> >> > % sfdisk -d /dev/mmcblk0 > mmcblk0 .out >> >> > sfdisk is a tool provided with the util-linux >> >> > package<http://www.kernel.org/pub/linux/utils/util-linux/>. >> >> > >> >> > >> >> > or you could use hexdump to get machine readable or man readable >> images. >> >> > Here is the man readable version: >> >> > hd -n512 /dev/mmcblk0 > backup-mmcblk0.mbr >> >> > hd -n512 /dev/mmcblk0p1 >backup-mmcblk0p1.mbr >> >> > etc. >> >> > >> >> > By the way boor records always end with '55 AA'. >> >> > >> >> > Keep your files in a safe place in case we mess something we can at >> >> > least >> >> go >> >> > back to the present situation. >> >> > If you could dd the whole drive to a file, now that would be magic >> >> indeed! >> >> > but you must have the space on a harddrive. >> >> > count=... is the number of sectors in the above line (dd ...) that >> >> > you >> >> dump >> >> > to file. >> >> > Hexedit will tell you the number of sectors is you start it with -s >> >> option >> >> > and then go to the last sector. >> >> > DONT stop hexedit with control-x use cntl-c. >> >> > DONT use high level or even midlevel tools on a stuffed disk, it >> >> > normally >> >> > messes more than it solves. >> >> > unless of course you really,really know what you are doing. >> >> > Fiddling the bytes is in general safe and gives results, if a man >> keeps >> >> > a >> >> > cool head. >> >> > >> >> > Please send me the fdisk version, the size of the card, and the mbr >> dump >> >> to >> >> > feast my eyes on. >> >> > >> >> > cheers, >> >> > >> >> > Jan de kruyf. >> >> > >> >> > >> >> > >> >> > On Tue, Nov 3, 2009 at 1:27 AM, Paul L <[email protected]> wrote: >> >> > >> >> >> just want to add that I've always been using 1 partition on this >> >> >> device, it's actually /dev/mmcblk0p1. But hexedit /dev/mmcblk0p1 >> >> >> doesn't show that 34 34 at line begining with 0x400, only hexedit >> >> >> /dev/mmcblk0 shows it. Not sure if this is a problem. >> >> >> >> >> >> Any help is greatly appreciated! >> >> >> >> >> >> >> >> >> On 11/2/09, Paul L <[email protected]> wrote: >> >> >> > Thanks for the tips. When I first used the SD card, I used fdisk >> >> >> > to >> >> >> > create the partition. >> >> >> > >> >> >> > The device is /dev/mmcblk0, and hexedit -d -s /dev/mmcblk0 shows >> that >> >> >> > at the line 0x0400, it is indeed 34 34. What should I do then? >> >> >> > >> >> >> > I tried gparted, but apparently it has no support for nilfs2. >> >> >> > >> >> >> > Regards, >> >> >> > Paul Liu >> >> >> > >> >> >> > On 11/2/09, Jan de Kruyf <[email protected]> wrote: >> >> >> >> Did you first format this card with fdisk? >> >> >> >> did you give it the exact same info this time around? >> >> >> >> >> >> >> >> Can you read /dev/'sdcard' ? (sdcard being the device in the dev >> >> >> >> directory >> >> >> >> where the card lives) >> >> >> >> >> >> >> >> If yes can you run hexedit -s /dev/sdcard1 in a terminal as >> >> >> >> root? >> >> >> >> and go to address 0400 - 04B0 to see if nilfs still exists? >> >> >> >> >> >> >> >> be very careful no to save any data in hexedit, it will >> >> >> >> definitely >> >> and >> >> >> >> finally >> >> >> >> destoy your data. >> >> >> >> >> >> >> >> 0400 looks vagely like this: >> >> >> >> 00000400 02 00 00 00 00 00 34 34 00 01 00 00 D3 56 F0 B9 >> >> >> >> ......44.....V.. >> >> >> >> 00000410 39 BF D9 73 02 00 00 00 CA 02 00 00 00 00 00 00 >> >> >> >> 9..s............ >> >> >> >> 00000420 00 B4 66 65 01 00 00 00 01 00 00 00 00 00 00 00 >> >> >> >> ..fe............ >> >> >> >> 00000430 00 08 00 00 05 00 00 00 01 00 00 00 00 00 00 00 >> >> >> >> ................ >> >> >> >> 00000440 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >> >> >> >> ................ >> >> >> >> 00000450 00 48 16 00 00 00 00 00 73 95 DC 4A 00 00 00 00 >> >> >> >> .H......s..J.... >> >> >> >> 00000460 00 00 00 00 00 00 00 00 73 95 DC 4A 00 00 00 00 >> >> >> >> ........s..J.... >> >> >> >> 00000470 00 00 32 00 01 00 01 00 73 95 DC 4A 00 00 00 00 >> >> >> >> ..2.....s..J.... >> >> >> >> 00000480 00 4E ED 00 00 00 00 00 00 00 00 00 0B 00 00 00 >> >> >> >> .N.............. >> >> >> >> 00000490 80 00 20 00 C0 00 10 00 4C 73 DD 3D 01 EC 45 85 .. >> >> >> >> .....Ls.=..E. >> >> >> >> 000004A0 94 28 44 42 3D F6 EF EC 56 61 72 36 34 00 00 00 >> >> >> >> .(DB=...Var64... >> >> >> >> 000004B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >> >> >> >> ................ >> >> >> >> 000004C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >> >> >> >> ................ >> >> >> >> >> >> >> >> the 34 34 in the top line say this is nilfs. >> >> >> >> >> >> >> >> >> >> >> >> cheers >> >> >> >> >> >> >> >> jan de kruyf >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> On Mon, Nov 2, 2009 at 9:06 PM, Paul L <[email protected]> wrote: >> >> >> >> >> >> >> >>> Due to some careless handling of my laptop, the SD card popped >> out >> >> >> >>> when the machine is still running. When I put it back in and >> reboot >> >> >> >>> the machine, it says "partition table error". I then ran fdisk >> and >> >> >> >>> recreated the single partition. Then I can no longer mount the >> >> nilfs2 >> >> >> >>> partition that was on the SD card! >> >> >> >>> >> >> >> >>> Can any one help to me recover the file system? I believe all >> data >> >> are >> >> >> >>> still there, but just some bits and pieces are missing for the >> >> >> >>> mount >> >> >> >>> to work. Any help is greatly appreciated! >> >> >> >>> >> >> >> >>> PS: I've a deadline to meet in 4 hours, not sure if I can get my >> >> stuff >> >> >> >>> back in time... so help please! >> >> >> >>> >> >> >> >>> -- >> >> >> >>> Regards, >> >> >> >>> Paul Liu >> >> >> >>> >> >> >> >>> Yale Haskell Group >> >> >> >>> http://www.haskell.org/yale >> >> >> >>> _______________________________________________ >> >> >> >>> users mailing list >> >> >> >>> [email protected] >> >> >> >>> https://www.nilfs.org/mailman/listinfo/users >> >> >> >>> >> >> >> >> >> >> >> > >> >> >> > >> >> >> > -- >> >> >> > Regards, >> >> >> > Paul Liu >> >> >> > >> >> >> > Yale Haskell Group >> >> >> > http://www.haskell.org/yale >> >> >> > >> >> >> >> >> >> >> >> >> -- >> >> >> Regards, >> >> >> Paul Liu >> >> >> >> >> >> Yale Haskell Group >> >> >> http://www.haskell.org/yale >> >> >> _______________________________________________ >> >> >> users mailing list >> >> >> [email protected] >> >> >> https://www.nilfs.org/mailman/listinfo/users >> >> >> >> >> > >> >> >> >> >> >> -- >> >> Regards, >> >> Paul Liu >> >> >> >> Yale Haskell Group >> >> http://www.haskell.org/yale >> >> >> >> _______________________________________________ >> >> users mailing list >> >> [email protected] >> >> https://www.nilfs.org/mailman/listinfo/users >> >> >> >> >> > >> >> >> -- >> Regards, >> Paul Liu >> >> Yale Haskell Group >> http://www.haskell.org/yale >> _______________________________________________ >> users mailing list >> [email protected] >> https://www.nilfs.org/mailman/listinfo/users >> > -- Regards, Paul Liu Yale Haskell Group http://www.haskell.org/yale _______________________________________________ users mailing list [email protected] https://www.nilfs.org/mailman/listinfo/users
