Until now if one of device's first superblock is corrupt,btrfs will
fail to mount. Luckily, btrfs have at least two superblocks for
every disk.
In theory, if silent corrupting happens when we are writting superblocks
into disk, we must hold at least one good superblock.
One side effect is that user must gurantee that the disk must be
a btrfs disk. Otherwise, this tool may destroy other fs.(This is also
reason why btrfs only use first superblock in every disk to mount)
This little program will try to correct bad superblocks from
good superblocks with max generation.
There will be five kinds of return values:
0: all supers are valid, no need to recover
1: usage or syntax error
2: recover all bad superblocks successfully
3: fail to recover bad superblocks
4: abort to recover bad superblocks
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
If some fatal superblocks are damaged, running ioctl will return failure,
in this case, we should avoid run ioctl.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
In files copied from the kernel, mark many functions as static,
and remove any resulting dead code.
Some functions are left unmarked if they aren't static in the
kernel tree.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
For most time, In open_ctree_*(), we use the first superblock
(BTRFS_SUPER_INFO_OFFSET). However, for btrfs-convert, we don't,
we should pass the correct sb_bytenr to btrfs_scan_fs_devices() rather
than always use BTRFS_SUPER_INFO_OFFSET.This patch fix the following
regression:
mkfs.ext2 <dev>
btrfs-convert <dev>
warning, device 1 is missing
Check tree block failed, want=2670592, have=0
read block failed check_tree_block
Couldn't read chunk root
Segmentation fault (core dumped)
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This adds a 'btrfs-image -m' option, which let us restore an image that
is built from a btrfs of multiple disks onto several disks altogether.
This aims to address the following case,
$ mkfs.btrfs -m raid0 sda sdb
$ btrfs-image sda image.file
$ btrfs-image -r image.file sdc
---------
so we can only restore metadata onto sdc, and another thing is we can
only mount sdc with degraded mode as we don't provide informations of
another disk. And, it's built as RAID0 and we have only one disk,
so after mount sdc we'll get into readonly mode.
This is just annoying for people(like me) who're trying to restore image
but turn to find they cannot make it work.
So this'll make your life easier, just tap
$ btrfs-image -m image.file sdc sdd
---------
then you get everything about metadata done, the same offset with that of
the originals(of course, you need offer enough disk size, at least the disk
size of the original disks).
Besides, this also works with raid5 and raid6 metadata image.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Add chunk-recover program to check or rebuild chunk tree when the system
chunk array or chunk tree is broken.
Due to the importance of the system chunk array and chunk tree, if one of
them is broken, the whole btrfs will be broken even other data are OK.
But we have some hint(fsid, checksum...) to salvage the old metadata.
So this function will first scan the whole file system and collect the
needed data(chunk/block group/dev extent), and check for the references
between them. If the references are OK, the chunk tree can be rebuilt and
luckily the file system will be mountable.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
In fact, the code of many rb-tree insert/search/delete functions is similar,
so we can abstract them, and implement common functions for rb-tree, and then
simplify them.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
All we need for restore to work is the chunk root, the tree root and the fs root
we want to restore from. So to do this we need to make a few adjustments
1) Make open_ctree_fs_info fail completely if it can't read the chunk tree.
There is no sense in continuing if we can't read the chunk tree since we won't
be able to translate logical to physical blocks.
2) Use open_ctree_fs_info in restore, and if we didn't load a tree root or
fs root go ahead and try to set those up manually ourselves.
This is related to work I did last year on restore, but it uses the
open_ctree_fs_info instead of my open coded open_ctree. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
__setup_root() was present in find-root.c as well
as disk-io.c. No need for the cut and paste, just
use the one in disk-io.c
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Zach Brown <zab@redhat.com>
David Woodhouse originally contributed this code, and Chris Mason
changed it around to reflect the current design goals for raid56.
The original code expected all metadata and data writes to be full
stripes. This meant metadata block size == stripe size, and had a few
other restrictions.
This version allows metadata blocks smaller than the stripe size. It
implements both raid5 and raid6, although it does not have code to
rebuild from parity if one of the drives is missing or incorrect.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
fsck needs to be able to open a damaged FS, which means open_ctree needs
to be able to return a damaged FS.
This adds a new open_ctree_fs_info which can be used to open any and all
roots that are valid. btrfs-debug-tree is changed to use it.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Btrfs stores multiple copies of the superblock, and for common power-failure
crashes where barriers were not in use, one of the super copies is often
valid while the first copy is not.
This adds a btrfs-select-super -s N /dev/xxx command, which can
overwrite all the super blocks with a copy that you have already
determined is valid with btrfsck -s
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit introduces a new kind of back reference for btrfs metadata.
Once a filesystem has been mounted with this commit, IT WILL NO LONGER
BE MOUNTABLE BY OLDER KERNELS.
The new back ref provides information about pointer's key, level and in which
tree the pointer lives. This information allow us to find the pointer by
searching the tree. The shortcoming of the new back ref is that it only works
for pointers in tree blocks referenced by their owner trees.
This is mostly a problem for snapshots, where resolving one of these fuzzy back
references would be O(number_of_snapshots) and quite slow. The solution used
here is to use the fuzzy back references in the common case where a given tree
block is only referenced by one root, and use the full back references when
multiple roots have a reference
This patch updates the ext3 to btrfs converter for the new
disk format. This mainly involves changing the convert's
data relocation and free space management code. This patch
also ports some functions from kernel module to btrfs-progs.
Thank you,
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
This patch updates btrfs-progs for superblock duplication.
Note: I didn't make this patch as complete as the one for
kernel since updating the converter requires changing the
code again. Thank you,
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
This is the btrfs-progs version of the patch to add the ability to have
different csum algorithims. Note I didn't change the image maker since it
seemed a bit more complicated than just changing some stuff around so I will let
Yan take care of that.
Everything else was converted and for now a mkfs just
sets the type to be BTRFS_CSUM_TYPE_CRC32.
Signed-off-by: Josef Bacik <jbacik@redhat.com>
