Re: btrfs restore

[Marc MERLIN <marc@merlins.org>]

I just created 
https://btrfs.wiki.kernel.org/index.php/Btrfs-zero-log

and added the info about this failure of btrfs-zero-log as well as the
patch from Chris.
Whenever it's in a new version of btrfs-zero-log, I or someone else can
update that wiki page to tell people to just update to a newer version
to get around this "Couldn't setup log root tree" problem.

However, re-reading your error message you got a different error, so the
patch isn't likely to work for you

read block failed check_tree_block 
is a warhing

Your actual error is
	if (!extent_buffer_uptodate(root->node)) {
		fprintf(stderr, "Couldn't read tree root\n");
		return -EIO;
	}

This looks more serious, and I'm not sure if btrfs-zero-log can help
with that.

I'll let someone else answer.

Marc


On Thu, Aug 21, 2014 at 06:52:16PM -0700, Marc MERLIN wrote:
> On Thu, Aug 21, 2014 at 05:52:01AM +0000, Mihail Zaporozhets wrote:
> > # btrfs-zero-log /dev/sda1                         
> > warning devid 5 not found already
> > Check tree block failed, want=16845270495232, have=0
> > read block failed check_tree_block
> > Couldn't read tree root
> 
> You may be hitting the same problem I was a week back. See the thread
> that says "btrfs-zero-log fails, can't mount FS"
> 
> Download the source for btrfs-progs, and apply this patch from Chris:
> 
> diff --git a/disk-io.c b/disk-io.c
> index 8db0335..d9a8e19 100644
> --- a/disk-io.c
> +++ b/disk-io.c
> @@ -911,13 +911,13 @@ int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
>                         return -EIO;
>         }
>         fs_info->csum_root->track_dirty = 1;
> -
> +#if 0
>         ret = find_and_setup_log_root(root, fs_info, sb);
>         if (ret) {
>                 printk("Couldn't setup log root tree\n");
>                 return -EIO;
>         }
> -
> +#endif
>         fs_info->generation = generation;
>         fs_info->last_trans_committed = generation;
>         if (extent_buffer_uptodate(fs_info->extent_root->node) &&
> 
> 
> Or if you're desparate and want a binary, I'll Email you one directly
> (not that you should run a binary you got from someone via Email as
> root, so it's only if you're desperate)
> 
> Marc
> -- 
> "A mouse is a device used to point at the xterm you want to type in" - A.S.R.
> Microsoft is to operating systems ....
>                                       .... what McDonalds is to gourmet cooking
> Home page: http://marc.merlins.org/                         | PGP 1024R/763BE901

-- 
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
                                      .... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/                         | PGP 1024R/763BE901