The function read_extent_from_disk() is only a wrapper to read tree
block.
And read_extent_data() is just a while loop to eliminate short read
caused by stripe boundary.
In fact, a lot of call sites of read_extent_data() are either reading
metadata (thus no possible short read) or doing extra loop by
themselves.
This patch will replace those two functions with read_data_from_disk(),
making it the only entrance for data/metadata read.
And update read_data_from_disk() to return the read bytes, so caller can
do a simple while loop.
For the few callers of read_extent_data(), open-code a small while loop
for them.
This will allow later RAID56 read repair using P/Q much easier.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're going to start create global roots from mkfs, and we need to have
a offset set for the root key. Make the btrfs_create_tree() take a key
for the root_key instead of just the objectid so we can setup these new
style roots properly.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The free space tree code already does this, but we need it for cleaning
up per block group roots. Abstract this code out into a helper so that
we can use it in multiple places in the future.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We will now be using block_group->chunk_objectid to point at the global
root id for this particular block group. For now we'll assign this
based on mod'ing the offset of the block group against the number of
global root id's and handle the block_group_item updating appropriately.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds the ability to load the block group root, as well as make sure
the various backup super block and super block updates are made
appropriately.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is still work in progress but can survive some stress testing.
There are still some sanity checks missing, do not user this on valuable
data. To enables this, configure must be run with the experimental
features enabled.
$ mkfs.btrfs --csum crc32c /dev/sdx
$ <mount, fill with data, unmount>
$ btrfstune --csum sha256
Will change the checksum to sha256.
Implementation:
- set bit on superblock when the checksums are being changed (similar to
the uuid rewrite)
- metadata checksums are overwritten in place
- data checksums:
- the checksum tree is completely deleted and no checksums are
verified
- data blocks are enumerated and all checksums generated (same as
check --init-csum-tree)
To make it usable, it should be restartable and track the current
progress somehow. Also the previous data checksums should be verified
any time they're available.
Signed-off-by: David Sterba <dsterba@suse.com>
We are going to have multiples of these trees with extent tree v2, so
add a rb tree to track them based on their root key value. This works
for both v1 and v2, so we can remove the direct pointers to these roots
in our fs_info.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we switch to multiple global trees we'll need to access the
appropriate extent root depending on the block group or possibly root.
To handle this, use a helper in most places and then the actual root in
places where it is required. We will whittle down the direct accessors
with future patches, but this does the bulk of the preparatory work.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With extent tree v2 we will have per-block group checksums, so add a
helper to access the csum root and rename the fs_info csum_root to
_csum_root to catch all the places that are accessing it directly.
Convert everybody to use the helper except for internal things.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Just like kernel change, pad struct btrfs_super_block to 4096 bytes. As
ctree.h is part of public headers, use raw number for the superblock
offset.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
There is a report that, btrfstune can even work while the fs has transid
mismatch problems.
$ btrfstune -f -u /dev/sdb1
Current fsid: b2b5ae8d-4c49-45f0-b42e-46fe7dcfcb07
New fsid: b2b5ae8d-4c49-45f0-b42e-46fe7dcfcb07
Set superblock flag CHANGING_FSID
Change fsid in extents
parent transid verify failed on 792854528 wanted 20103 found 20091
parent transid verify failed on 792854528 wanted 20103 found 20091
parent transid verify failed on 792854528 wanted 20103 found 20091
Ignoring transid failure
parent transid verify failed on 792870912 wanted 20103 found 20091
parent transid verify failed on 792870912 wanted 20103 found 20091
parent transid verify failed on 792870912 wanted 20103 found 20091
Ignoring transid failure
parent transid verify failed on 792887296 wanted 20103 found 20091
parent transid verify failed on 792887296 wanted 20103 found 20091
parent transid verify failed on 792887296 wanted 20103 found 20091
Ignoring transid failure
ERROR: child eb corrupted: parent bytenr=38010880 item=69 parent level=1 child level=1
ERROR: failed to change UUID of metadata: -5
ERROR: btrfstune failed
This leaves a corrupted fs even more corrupted, and due to the extra
CHANGING_FSID flag, btrfs check will not even try to run on it:
Opening filesystem to check...
ERROR: Filesystem UUID change in progress
ERROR: cannot open file system
[CAUSE]
Unlike kernel, btrfs-progs has a less strict check on transid mismatch.
In read_tree_block() we will fall back to use the tree block even its
transid mismatch if we can't find any better copy.
However not all commands in btrfs-progs needs this feature, only
btrfs-check (which may fix the problem) and btrfs-restore (it just tries
to ignore any problems) really utilize this feature.
[FIX]
Introduce a new open ctree flag, OPEN_CTREE_ALLOW_TRANSID_MISMATCH, to
be explicit about whether we really want to ignore transid error.
Currently only btrfs-check and btrfs-restore will utilize this new flag.
Also add btrfs-image to allow opening such fs with transid error.
Link: https://www.reddit.com/r/btrfs/comments/pivpqk/failure_during_btrfstune_u/
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For passing authentication keys to the checksumming functions we need a
container for the key.
Pass in a btrfs_fs_info to btrfs_csum_data() so we can use the fs_info
as a container for the authentication key.
Note this is not always possible for all callers of btrfs_csum_data() so
we're just passing in NULL for now
Functions calling btrfs_csum_data() with a NULL fs_info argument are
currently not supported in the context of an authenticated file system.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Extending open_ctree with more parameters would be difficult, we'll need
to add more so factor out the parameters to a structure for easier
extension.
Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo
Josef Bacik
David Sterba
Johannes Thumshirn