just thought of something. You searched with standard (little, I think) endianess i.e. the image from my mail to you. try the image from YOUR main superblock: 0002 0000 0000 3434 and see if the backup copy surfaces.
jan. On Wed, Nov 4, 2009 at 9:31 PM, Paul L <[email protected]> wrote: > 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 >
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