Le 20/09/2016 à 20:56, Austin S. Hemmelgarn a écrit : > On 2016-09-20 13:54, Chris Murphy wrote: >> On Tue, Sep 20, 2016 at 11:03 AM, Alexandre Poux <pums974@xxxxxxxxx> >> wrote: >> >>> If I wanted to try to edit my partitions with an hex editor, where >>> would >>> I find infos on how to do that ? >>> I really don't want to go this way, but if this is relatively >>> simple, it >>> may be worth to try. >> >> Simple is relative. First you'd need >> https://btrfs.wiki.kernel.org/index.php/On-disk_Format to get some >> understanding of where things are to edit, and then btrfs-map-logical >> to convert btrfs logical addresses to physical device and sector to >> know what to edit. >> >> I'd call it distinctly non-trivial and very tedious. >> > It really is. I've done this before, but I had a copy of the on-disk > format documentation, a couple of working filesystems, a full copy of > the current kernel sources for reference, and about 8 cups of green > tea (my beverage of choice for staying awake and focused). I got > _really_ lucky and it was something that really was simple to fix once > I found it (it amounted to about 64 bytes of changes, it took me maybe > 5 minutes to actually correct the issue once I found where it was), > but it took me a good couple of hours to figure out what to even look > for, plus another hour just to find it, and I'm not sure I would be > able to do it any faster if I had to again (unlike doing so for ext4, > which is a walk in the park by comparison). > > TBH the only thing I'd worry about using a hex editor to fix in BTRFS > is the super-blocks or system chunks, because they're pretty easy to > find, and usually not all that hard to fix. In fact, if it hadn't > been for the fact that I had no backup of the data I would lose by > recreating that filesystem, and I was _really_ bored that day, I > probably wouldn't have even tried. OK I will forget this. Thank you -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
