Function find_possible_backrefs() is used to locate the file extents
referring to an data extent.
For data extent backref, its btrfs_extent_data_ref structure has
the following members:
- root
Which root refers to this data extent
- objectid
Which inode refers to this data extent
- offset
Search *hint*.
Its value is @file_offset - @extent_offset.
While for @file_offset, it's directly recorded in (INO EXTENT_DATA
FILE_OFFSET) key.
So when searching the file extents refers to this data extent, we can't
use btrfs_extent_data_ref::offset as search key::offset.
We must search from file offset 0, and iterate all file extents until we
hit a file extent matches the data backref.
Thankfully such time consuming behavior is not triggered frequently,
it only gets called for repair, so it shouldn't affect normal check
routine.
Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
[Update commit message]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Commit 0ddf63c09f ("btrfs-progs: Record orphan data extent ref to
corresponding root.") introduces the ability to record a file extent
even all other related info is lost (data backref, inode item).
However this patch only records such info without doing any proper
repair, further more, it could even record invalid file extents, and the
report part only happens after all check is done.
Since we will later introduce proper file extent repair functionality,
we could revert that patch.
Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
[Update commit message, solve merge conflicts]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Commit ad03f840f0 ("btrfs-progs: Add repair and report function for
orphan file extent.") will record and try to repair orphan file extents
by:
- Removing the orphan file extent item if no extent backref can be found
Or
- Re-insert a file extent using data backref
Especially the later case is far from ideal, as normally extent tree is
more fragile and corruption prone.
Use any data from extent tree to try to repair could easily lead to
further corruption.
So here we revert commit ad03f840f0 ("btrfs-progs: Add repair and report
function for orphan file extent.") to cleanup the space for later proper
repair in original mode.
Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
[Update commit message, solve conflicts with DIR_ITEM hash mismatch patchset]
Signed-off-by: Qu Wenruo <wqu@suse.com>
If found a extent data item has unaligned part, lowmem repair
just deletes it.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
The function can delete items in trees besides extent tree.
Rename and move it for further use.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
[Update comment, solve merge conflicts]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Add support to check unaligned disk_bytenr for extent_data.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Previously, @err are assigned immediately after check but before
repair.
repair_extent_item()'s return value also confuses the caller. If
error has been repaired and returns 0, check_extent_item() will try
to continue check the nonexistent and cause flase alerts.
Here make repair_extent_item()'s return codes only represents status
of the extent item, error bits are handled in caller of the repair
function.
Change of @err after repair.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
[Solve conflicts with DIR_ITEM hash mismatch patchset]
Signed-off-by: Qu Wenruo <wqu@suse.com>
For files, lowmem repair will try to check nbytes and isize,
but isize check depends nbytes.
Once bytes has been repaired, then isize should be checked and
repaired.
So move nbytes check before isize check. Also set nbytes to
extent_size once repaired successfully.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Since repair will do CoW, the outer path may be invalid.
This patch will add an argument, @path, to punch_extent_hole().
When punch_extent_hole() returns, path will still point to the same key.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
[Update comment and commit message]
Signed-off-by: Qu Wenruo <wqu@suse.com>
The 'end' parameter of check_file_extent tracks the ending offset of the
last checked extent. This is used to detect gaps between adjacent extents.
Currently such gaps are wrongly detected since for regular extents only
the size of the extent is added to the 'end' parameter. This results in
wrongly considering all extents of a file as having gaps between them
when only 2 of them really have a gap as seen in the example below.
Solution:
The extent_end variable should set to the sum of the offset and the
extent_num_bytes of the file extent.
Example:
Suppose that lowmem check the following file extent of inode 257.
item 6 key (257 EXTENT_DATA 0) itemoff 15813 itemsize 53
generation 6 type 1 (regular)
extent data disk byte 13631488 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression 0 (none)
item 7 key (257 EXTENT_DATA 8192) itemoff 15760 itemsize 53
generation 6 type 1 (regular)
extent data disk byte 13631488 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression 0 (none)
item 8 key (257 EXTENT_DATA 12288) itemoff 15707 itemsize 53
generation 6 type 1 (regular)
extent data disk byte 13631488 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression 0 (none)
For inode 257, check_inode_item set extent_end to 0, then call
check_file_extent to check item {6,7,8}.
item 6)
offset(0) == extent_end(0)
extent_end = extent_end(0) + extent_num_bytes(4096)
item 7)
offset(8192) != extent_end(4096)
extent_end = extent_end(4096) + extent_num_bytes(4096)
^^^
The old extent_end should replace by offset(8192).
item 8)
offset(12288) != extent_end(8192)
^^^
But there is no gap between item {7,8}.
Fixes: d88da10ddd ("btrfs-progs: check: introduce function to check file extent")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
[Move this patch as the 1st patch, since it's an independent fix]
Signed-off-by: Qu Wenruo <wqu@suse.com>
GCC 8.2.1 will report the following error:
check/main.c: In function 'try_repair_inode':
check/main.c:2606:5: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]
if (!ret) {
^
check/main.c:2584:6: note: 'ret' was declared here
int ret;
^~~
The offending code is in repair_mismatch_dir_hash():
int ret;
printf(
"Deleting bad dir items with invalid hash for root %llu ino %llu\n",
root->root_key.objectid, rec->ino);
while (!list_empty(&rec->mismatch_dir_hash)) {
/* do some repair */
}
if (!ret) { <<< Here
/* do some fix */
}
The truth is, to enter try_repair_inode(), we must have
I_ERR_MISMATCH_DIR_HASH bit set for rec->errors.
And just after we set I_ERR_MISMATCH_DIR_HASH, we call
add_mismatch_dir_hash() and handled its error correctly.
So it's impossible to to skip the while loop.
Fix it by initializing @ret to -EUCLEAN, so even we hit some impossible
case, repair_mismatch_dir_hash() won't falsely consider the mismatch
hash fixed.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit e578b59bf6 ("btrfs-progs: convert strerror to implicit %m")
missed adding braces after a conditional so we will see the following
message whenever a tree block needs repair, regardless of whether repair
was successful: "Failed to repair btree: Success"
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The repair function is reusing delete_corrupted_dir_item().
Since the error can happen for root dir inode, also call
try_repair_inode() on root dir inode.
This is especially important for old filesystems, since later kernel
introduces stricter tree-checker, which could detect such hash mismatch
and refuse to read the corrupted leaf.
With this repair ability, user could repair with btrfs check --repair.
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1111991
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This changes reporting from current in-place, like:
ERROR: DIR_ITEM[256 751495445] name foor.WvG1c1TdU namelen 13 filetype 1 mismatch with its hash, wanted 751495445 have 2870353892
root 5 root dir 256 error
To new summary report at the end of the pass:
root 5 root dir 256 error
root 5 inode 256 errors 40000
Dir items with mismatch hash:
name: foor.WvG1c1Td namelen: 13 wanted 0xab161fe4 has 0x2ccae915
Also, with mismatch_dir_hash_record structure, it provides the base for
later original mode repair.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For DIR_ITEM with mismatch hash, we could just remove the offending dir
item from the tree.
Lowmem mode will handle the rest, either re-create the correct dir_item
or move the orphan inode to lost+found.
This is especially important for old filesystems, since later kernel
introduces stricter tree-checker, which could detect such hash mismatch
and refuse to read the corrupted leaf.
With this repair ability, user could repair with 'btrfs check
--mode=lowmem --repair'.
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1111991
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unlike lowmem mode check, we don't have good place for original mode to
check overlapping device extents.
So this patch introduces a new function, btrfs_check_dev_extents(), to
handle such extents.
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add such check to check_dev_item(), since at that time we're also
iterating dev extents for dev item accounting.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add support for a new metadata_uuid field. This is just a preparatory
commit which switches all users of the fsid field for metdata comparison
purposes to utilize the new field. This more or less mirrors the
kernel patch, additionally:
* Update 'btrfs inspect-internal dump-super' to account for the new
field. This involes introducing the 'metadata_uuid' line to the
output and updating the logic for comparing the fs uuid to the
dev_item uuid.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Move "\n" at end of the sentence to print.
Fixes: 281eec7a9d ("btrfs-progs: check: repair inode nbytes in lowmem mode")
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This header is exported to /usr/include/btrfs but there are no known
users, so the change should be safe.
Generated by https://github.com/jsoref/spelling
Issue: #154
Author: Josh Soref <jsoref@users.noreply.github.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Found using -Wmissing-prototypes in GCC. This should improve LTO
behavior.
Note that set_free_space_tree_thresholds is an unused function. Adding
inline seems to remove the unused function warning.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Rosen Penev <rosenp@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Similar to the changes where strerror(errno) was converted, continue
with the remaining cases where the argument was stored in another
variable.
The savings in object size are about 4500 bytes:
$ size btrfs.old btrfs.new
text data bss dec hex filename
805055 24248 19748 849051 cf49b btrfs.old
804527 24248 19748 848523 cf28b btrfs.new
Signed-off-by: David Sterba <dsterba@suse.com>
Make the checks in check_file_extent a bit more explicit. First we check
for unknown type and fail accordingly. Then we check for inline extent
and handle it in the newly introduced check_file_extent_inline. Finally
if none of the above checks triggered then we must have a regular or
prealloc extents.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of having another top-level if which checks for
'extent_num_bytes != item_inline_len' only if we are !compressed, just
move the 'if' inside the 'else' branch of the first top-level if, since
it has already checked for !compressed or not. No functional changes.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since the inline extent code can be largely self-sufficient, factor
it out from check_file_extent. No functional changes.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that all the prerequisite code for proper support of free space
tree repair is in, it's time to wire it in. This is achieved by first
hooking the freespace tree to the __free_extent/alloc_reserved_tree_block
functions. And then introducing a wrapper function to contains the
existing check_space_cache and the newly introduced repair code.
Finally, it's important to note that FST repair code first clears the
existing FST in case of any problem found and rebuilds it from scratch.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit enables the delayed refs infrastructures. This entails doing
the following:
1. Replacing existing calls of btrfs_extent_post_op (which is the
equivalent of delayed refs) with the proper btrfs_run_delayed_refs.
As well as eliminating open-coded calls to finish_current_insert and
del_pending_extents which execute the delayed ops.
2. Wiring up the addition of delayed refs when freeing extents
(btrfs_free_extent) and when adding new extents (alloc_tree_block).
3. Adding calls to btrfs_run_delayed refs in the transaction commit
path alongside comments why every call is needed, since it's not
always obvious (those call sites were derived empirically by running
and debugging existing tests)
4. Correctly flagging the transaction in which we are reinitialising
the extent tree.
5. Moving btrfs_write_dirty_block_groups to
btrfs_write_dirty_block_groups since blockgroups should be written to
disk after the last delayed refs have been run.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
An infinite loop can be triggered during fuzz/003:
====== RUN MAYFAIL btrfs check --repair tests/fuzz-tests/images/bko-199833-reloc-recovery-crash.raw.restored
[1/7] checking root items
Fixed 0 roots.
[2/7] checking extents
ctree.c:1650: leaf_space_used: Warning: assertion `data_len < 0` failed, value 1
bad key ordering 18 19
ctree.c:1650: leaf_space_used: Warning: assertion `data_len < 0` failed, value 1
bad key ordering 18 19
ctree.c:1650: leaf_space_used: Warning: assertion `data_len < 0` failed, value 1
bad key ordering 18 19
[CAUSE]
In try_to_fix_bad_block() it's possible that btrfs_find_all_roots()
finds no root referring to that tree block, thus we can't do any repair.
However in that case, we still return 0 since the last caller assigning
@ret is btrfs_find_all_roots(), and the ulist while loop doesn't get run
at all.
And since try_to_fix_bad_block() returns 0, check_block() in
check/main.c will return -EAGAIN to re-check the tree block.
This leads to the infinite loop.
[FIX]
Change the default return value from 0 to -EIO in
try_to_fix_bad_block(), so if there is no tree referring to the bad tree
block, it won't cause infinite loop anymore.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In check_inode_recs(), for repair mode we always reset @ret to 0. It
makes no sense and later we check @ret to determine if the repair is
successful.
Fix it by removing the offending overwrite.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Exposed by fuzz-tests/003-multi-check-unmounted/ on fuzzed image
bko-161811.raw.xz.
It's caused by the fact when check_fs_roots() finds tree root is
modified, it re-search tree root by goto again: label.
However again: label. will also reset root objectid to 0.
If we failed to repair one fs root but still modified tree root, we will
go into such infinite loop.
Fix it by recording which root we should skip for repair mode.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have function btrfs_fsck_reinit_root() to reinit csum or extent tree.
However this function allows us to let it overwrite existing tree blocks
using @overwrite parameter.
Such behavior is pretty dangerous while no caller is using this feature
explicitly.
So just remove @overwrite parameter and allow btrfs_fsck_reinit_root()
to error out when it fails to allocate tree block.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We reuse the task_position enum and task_ctx struct of the original progress
indicator, adding more values and fields for our needs.
Then add hooks in all steps of the check to properly record progress.
Here's how the output looks like on a 22 Tb 5-disk RAID1 FS:
Opening filesystem to check...
Checking filesystem on /dev/mapper/luks-ST10000VN0004-XXXXXXXX
UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
[1/7] checking extents (0:20:21 elapsed, 950958 items checked)
[2/7] checking root items (0:01:29 elapsed, 15121 items checked)
[3/7] checking free space cache (0:00:11 elapsed, 4928 items checked)
[4/7] checking fs roots (0:51:31 elapsed, 600892 items checked)
[5/7] checking csums (0:14:35 elapsed, 754522 items checked)
[6/7] checking root refs (0:00:00 elapsed, 232 items checked)
[7/7] checking quota groups skipped (not enabled on this FS)
found 5286458060800 bytes used, no error found
Signed-off-by: Stéphane Lesimple <stephane_btrfs@lesimple.fr>
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs lowmem check reports such false alerts:
=========
ERROR: extent[1419709677568, 1703936] referencer count mismatch (root: 2192, owner: 327635, offset: 0) wanted: 9, have: 13
=========
While in extent tree, the extent has:
=========
item 98 key (1419709677568 EXTENT_ITEM 1703936) itemoff 10745 itemsize 92
refs 35 gen 16921 flags DATA
extent data backref root 2192 objectid 327635 offset 0 count 9
shared data backref parent 1232784752640 count 4
shared data backref parent 1232784736256 count 13
shared data backref parent 1232784719872 count 9
=========
The extent data 327635 starts in this leaf without BTRFS_HEADER_FLAG_RELOC:
=========
leaf 1471521390592 items 146 free space 3671 generation 18581 owner 2192
leaf 1471521390592 flags 0x1(WRITTEN) backref revision 1
...
item 137 key (327635 EXTENT_DATA 0) itemoff 7745 itemsize 53
generation 15770 type 1 (regular)
extent data disk byte 1419709677568 nr 1703936
extent data offset 0 nr 131072 ram 1703936
extent compression 0 (none)
item 138 key (327635 EXTENT_DATA 131072) itemoff 7692 itemsize 53
generation 15770 type 1 (regular)
extent data disk byte 1419709677568 nr 1703936
extent data offset 131072 nr 131072 ram 1703936
extent compression 0 (none)
...(Exactly 9 items here)
=========
The next leaf is flaged as relocated, so extent data backrefs are
shared not keyed:
=========
leaf 1232784752640 items 159 free space 2503 generation 16924 owner 2192
leaf 1232784752640 flags 0x3(WRITTEN|RELOC) backref revision 1
fs uuid 0f43f49d-6e63-4b1b-bc8c-c54da409872d
chunk uuid e558e6f7-4f08-4292-91fb-9a775fdd530b
item 0 key (327635 EXTENT_DATA 1179648) itemoff 16230 itemsize 53
generation 15770 type 1 (regular)
extent data disk byte 1419709677568 nr 1703936
extent data offset 1179648 nr 131072 ram 1703936
extent compression 0 (none)
item 1 key (327635 EXTENT_DATA 1310720) itemoff 16177 itemsize 53
generation 15770 type 1 (regular)
extent data disk byte 1419709677568 nr 1703936
extent data offset 1310720 nr 131072 ram 1703936
extent compression 0 (none)
item 2 key (327635 EXTENT_DATA 1441792) itemoff 16124 itemsize 53
generation 15770 type 1 (regular)
extent data disk byte 1419709677568 nr 1703936
extent data offset 1441792 nr 131072 ram 1703936
extent compression 0 (none)
item 3 key (327635 EXTENT_DATA 1572864) itemoff 16071 itemsize 53
=======
Lowmem mode starts to count extent data backrefs in first leaf, those
backrefs are keyed as wanted.
It calls btrfs_next_item to skip to next leaf.
However, the next leaf was relocated, extent data items in this leaf
should have shared backrefs shouldn't be counted.
So let lowmem mode do not count data backrefs if leaf is flaged with
BTRFS_HEADER_FLAG_RELOC.
Reported-by: Chris Murphy <chris@colorremedies.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With crafted image, expected root item can refer to certain extent, and
original mode uses BUG_ON() to handle such case.
Fix it by gracefully return error.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200403
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
They are not really needed, what free_extent_hook wants is really a
pointer to fs_info so give it to it directly. This is in preparation
of delayed refs code.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The experimental flag is already carried in the manpage, but was removed
from the btrfs check usage message as part of refactoring via
87c1bd13c1. Add it back.
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Similar to the original mode repair.
Reported-by: Steve Leung <sjleung@shaw.ca>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Current check_file_extent() doesn't support later repair work, since it
doesn't accept btrfs_path structure as parameter, thus it can't modify
btrfs trees, or later check will still use the old and wrong path.
Use btrfs_path to replace btrfs_key, extent_buffer and slot parameters,
so we can modify @path directly for repair, and reduce the number of
parameters for check_file_extent().
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It looks like that around 2014, btrfs kernel has a regression that would
cause offset-by-one ram_bytes for inline extent.
Add the ability to repair it in original mode.
Reported-by: Steve Leung <sjleung@shaw.ca>
Tested-by: Steve Leung <sjleung@shaw.ca>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
If one uncompressed inline extent has incorrect ram_bytes, neither btrfs
check nor dump-tree could detect such corruption.
[CAUSE]
Every caller tries to read inline extent ram_bytes is using
btrfs_file_extent_inline_len(), other than directly calling
btrfs_file_extent_ram_bytes().
For compressed extent, it's just calling btrfs_file_extent_ram_bytes().
However for uncompressed extent, it falls back to
btrfs_file_extent_inline_item_len(), makes us unable to detect anything
wrong in ram_bytes.
[FIX]
Just get rid of such confusing btrfs_file_extent_inline_len() function.
Reported-by: Steve Leung <sjleung@shaw.ca>
Tested-by: Steve Leung <sjleung@shaw.ca>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
check_chunks_and_extents does quite a number of distinct things. The
first of those is going through all root items in the root tree and
classify every root depending on whether they have a dropping operation
in progress or not. Lets factor out this code and move the variables
specific to this in a separate function so clean up check_chunks_and_extents
a bit. Accidentally, this patch fixes some reference leaks since
in error conditions in the loop the code does "goto out" but at that
label we don't really release the path. Having this code extracted in a
separate function which always releases the path avoids this problem
entirely.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The first thing that check_chunks_and_extents does is to iterate all
the root items in the root tree and link them to either the "normal_list"
or "dropping_trees" list. If a leaf has to be crossed during this
operation btrfs_next_leaf is called to do that. However, currently it's
called with a wrong argument for its 'root' parameter. Since we are
iterating the root tree the passed root should be fs_info->tree_rot,
whereas right now we are passing the local variable 'root' which is
assigned to the fs_tree. As it stands, this bug is actually benign since
the passed root is only passed to reada_for_search, where it's used to
reference the fs_info. Nevertheless the code is wrong and at the very least
misleading, so fix it by passing the correct root.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Initialize all filed of btrfs_inode_item to zero in order to prevent
having some garbage, especially for flags field.
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Define new error bit INODE_FLAGS_ERROR to represents invalid inode
flags error.
Symlinks should never have append/immutable flags set.
While checking inodes, if found a symlink with append/immutable
flags, report and record the inode flags error.
This is for lowmem mode.
Issue: #133
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Define new macro I_ERR_ODD_INODE_FLAGS to represents odd inode flags.
Symlinks should never have append/immutable flags.
While processing inodes, if found a symlink with append/immutable
flags, mark the inode record with I_ERR_ODD_INODE_FLAGS.
This is for original mode.
Issue: #133
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
That function really wants an fs_info and not a root. Accidentally,
this also makes the kernel/user space signatures to be coherent.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is no longer used by the callees of that function so remove it.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's always set to extent_root and the function already takes a
transaction handle where fs_info could be referenced and in turn
the extent_tree.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function is always passed the extent_root as "root" parameter. In
turn it uses the root parameter to mostly access fs_info and performs
only a single call to btrfs_update_block_group where it passses the
passed root. This is all redundant since fs_info can be referenced
from the transaction handle and in turn extent_root can be referenced
from the fs_info. So do that to simplify the function's signature.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For btrfs_leaf_free_space(), to get leaf data size, we have two way to
get it:
1) leaf->fs_info->nodesize
2) leaf->len
Anyway, we could get rid of @fs_info parameter for
btrfs_leaf_free_space().
And here we choose method 2), as it provides extra benefit to get leaf
free space without initializing a real fs_info.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All real consumers of that variable have inlined the checks since they
are simple enough. So just remove it.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's no longer used so just remove it.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's no longer used in that function so can be dropped altogether.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's no longer used so just remove it.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's no longer use and can be dropped.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's no longer used in the function so just remove it
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We can derive this argument from root->fs_info and also make it local
to the sole switch case it's used.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This parameter is no longer used in this function, so drop it
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a boolean parameter which signals whether the fs has the
EXTENDED_IREF feature flag toggled or not. Since a reference to fs_info
can be obtained there is no need to pollute the interface.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When checking the validity of a DIR_ITEM item the index variable is
explicitly set to -1 so that the index check in find_inode_ref() is
ignored. This is necessary due to possible name collisions in DIR_ITEMS
(i.e. multiple files with the same crc32c for their names, resulting in
the identical key->offset). Currently the code is broken due to index
being set to -1 at the beginning of check_dir_item and subsequently
reset to the index found in find_inode_ref. On subsequent iterations of
the while loop in check_dir_items we are going to erroneously perform
index checking, since index is not -1 but whatever the index value of
the last handled INODE_REF ITEM.
Without this patch check in lowmem mode produces the following false
warnings positivess:
ERROR: root 5 INODE REF[1991456, 256] name 5ab4e28b~~~~~~~~QBXUT2GBJDRT5CB6ZWAJVDHK filetype 1 missing
But the items for this name are in fact correct:
------------------SNIP------------------------
item 13 key (256 DIR_ITEM 4227063046) itemoff 2945 itemsize 140
location key (220890 INODE_ITEM 0) type FILE
transid 2278 data_len 0 name_len 40
name: 5ab4e1bb~~~~~~~~65KNTAWVJ5VD4SV2R3BKFCXL
location key (1991456 INODE_ITEM 0) type FILE
transid 2285 data_len 0 name_len 40
name: 5ab4e28b~~~~~~~~QBXUT2GBJDRT5CB6ZWAJVDHK
item 21 key (1991456 INODE_REF 256) itemoff 2104 itemsize 50
index 1934146 namelen 40 name: 5ab4e28b~~~~~~~~QBXUT2GBJDRT5CB6ZWAJVDHK
-------------------SNIP-------------------------
Fix this by moving the code setting index at the beginning of the while
loop. This ensure that for each item in DIR_ITEM we have index set
correctly.
Fixes: 564901eac7 ("btrfs-progs: check: introduce print_dir_item_err()")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Current btrfs-check will check qgroup consistency, but even when it
finds something wrong, the return value is still 0.
Fix it by allowing report_qgroups() to return int to indicate qgroup
mismatch, and also add extra logic to return no error if qgroup repair
is successful.
Without this patch, fstests can't detect qgroup corruption by its fsck
alone.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This parameter was introduced with the original implementation of the
function but has never really been used, so just remove it.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Remove @trans in check_chunks_and_extents_lowmem().
After this patch, lowmem repair works again.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Introduce repair_block_accounting() which calls
btrfs_fix_block_accounting() to repair block group accouting.
Replace btrfs_fix_block_accounting() with the new function.
Note: This patch and next patches cause error in lowmem repair like:
"Error: Commit_root already set when starting transaction".
Such error will disappear after removing @trans finished.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Remove parameters @trans of delete_extent_item() and walk_down_tree_v2().
Note: This patch and next patches cause error in lowmem repair like:
"Error: Commit_root already set when starting transaction".
Such error will disappear after removing @trans finished.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch removes parameter @trans of repair_tree_back_ref().
It calls try_avoid_extents_overwrite() and starts a transaction by
itself.
Note: This patch and next patches cause error in lowmem repair like:
"Error: Commit_root already set when starting transaction".
Such error will disappear after removing @trans finished.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch removes parameter @trans of check_leaf_items().
Note: This patch and next patches cause error in lowmem repair like:
"Error: Commit_root already set when starting transaction".
Such error will disappear after removing @trans finished.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch removes parameter @trans of repair_extent_item().
It calls try_avoid_extents_overwrite() and starts a transaction by
itself.
Note: This patch and next patches cause error in lowmem repair like:
"Error: Commit_root already set when starting transaction".
Such error will disappear after removing @trans finished.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch removes parameter @trans of repair_chunk_item().
It calls try_avoid_extents_overwrite() and starts a transaction by
itself.
Note: This patch and next patches cause error in lowmem repair like:
"Error: Commit_root already set when starting transaction".
Such error will disappear after removing @trans finished.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch removes the parameter @trans of delete_extent_item().
It calls try_avoid_extents_overwrite() and starts a transaction
by itself.
Note: This patch and next patches cause error in lowmem repair like:
"Error: Commit_root already set when starting transaction".
Such error will disappear after removing @trans finished.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since extents can be avoided to be overwrittten by excluding or chunk
allocation. It's not necessary to do all repairs in one transaction.
This patch removes parameter @trans of repair_extent_data_item().
repair_extent_data_item() calls try_avoid_extents_overwrite()
and starts a transaction by itself.
Note: This patch and next patches cause error in lowmem repair like:
"Error: Commit_root already set when starting transaction".
Such error will disappear after removing @trans finished.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If options '--init-extent-tree' and '--mode=lowmem' are both
input, all metadata blocks will be traversed twice.
First one is done by pin_metadata_blocks() in reinit_extent_tree().
Second one is in check_chunks_and_extents_v2().
Excluding instead of pinning metadata blocks before reinitializing th
extent tree in lowmem can save some time.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Declare a global u64 variable last_allocated_chunk records start of
the last chunk allocated by lowmem repair.
Although global variable is not nice, it simplifies the code a lot.
avoid_extents_overwrite() prefers to allocate a new chunk first.
If it failed because of no space or wrong used bytes (like in
fsck-tests/004), then it tries to exclude metadata blocks which costs
a lot of time in large filesystems.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Introduce create_chunk_and_block_block_group() to allocate a new chunk
and corresponding block group.
The new function force_cow_in_new_chunk() firstly allocates new chunk
and records its start.
Then it modifies all metadata block groups cached and full.
Finally it marks the new block group uncached and unfree.
In the next COW, extents states will be updated automatically by
cache_block_group().
New function try_to_force_cow_in_new_chunk() will try to mark block
groups full, allocate a new chunk and records the start.
If the last allocated chunk is almost full, a new chunk will be
allocated.
Suggested-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Excluding or pining all metadata blocks is time-inefficient for large
filesystems. Here is another way to mark all metadata block groups full
and allocate new chunks for COW. Then new reserved extents never
overwrite extents.
Introduce modify_block_groups_cache() to modify all blocks groups
cache state and set all extents in block groups unfree in free space
cache.
mark/clear_block_groups_full() are wrappers of above function.
Suggested-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit d17d6663c99c ("btrfs-progs: lowmem check: Fix regression which
screws up extent allocator") removes pin_metadata_blocks() from lowmem
repair. So we have to find another way to exclude extents which should
be occupied by existing tree blocks.
Modify pin_down_tree_blocks() and rename it to traverse_tree_blocks
for sharing code with new function exclude_metadata_blocks().
* exclude_metadata_blocks() traverses and marks extents of all tree
blocks dirty in fs_info->excluded_extents.
* cleanup_excluded_extents() is responsible for cleanup.
Export them to mode-common.h since they will be used both in original
and lowmem modes.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Move pin_down_tree_blocks from main.c to mode-common.c for
further patches.
And export pin_metadata_blocks to mode-common.h.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
No matter --check-data-csum is passed or not, btrfs check will always
output message like "checking csum".
This message could be a little confusing, change it according to
--check-data-csum option.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since data csum mismatch is not a fatal error compared to fs/extent
trees, continue check.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When --check-data-csum option found csum mismatch, btrfs check still
return 0.
Fix it so log-replay could automatically pause when it finds csum error.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Original --check-data-csum option will skip the extra copy if the first
copy matches csum.
Since offline scrub (with recoverability report) is still out-of-tree, at
least enhance --check-data-csum option to handle multiple copies.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The variable @eb is assigned to leaf in fs_tree before insertion of
backref. It will cause wrong parent of new inserted backref.
Set @parent at beginning to fix the problem.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In lowmem mode with '--repair', check_chunks_and_extents_v2 will fix
accounting in block groups and clear the error bit BG_ACCOUNTING_ERROR.
However, return value of check_btrfs_root() doesn't contain error bits.
If extent tree is on error, lowmem repair always prints error and
returns nonzero value even the filesystem is fine after repair.
Introduce FATAL_ERROR for lowmem mode to represent negative return
values since negative and positive can't be mixed in the bit operations.
Then let check_btrfs_root() return error bits.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In repair_extent_data_item(), path is not released if some errors occurs
which causes extent buffer leak.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For repair_ternary_lowmem() used in lowmem mode, if it found 1 of
DIR_INDEX/DIR_ITEM/INODE_REF missing, it will try to insert correct
link.
However for case like invalid type in DIR_INDEX, we should delete the
corrupted DIR_INDEX first before inserting the correct link.
This patch will remove the corrupted link before re-inserting.
This should solve the duplicated DIR_INDEX problem in old lowmem mode
repair.
Reported-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of struct btrfs_root, use struct btrfs_fs_info, since nodesize
is now a per-fs setting, and with the need to pass a @root, caller don't
need to wonder which root should be passed.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For metadata dump (fs restored by btrfs-image), no data is restored
and check sum verification will definitely report error.
Add such check in check_csums() and prompt for user input.
Issue: #103
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This @first_key variable is introduced in f5c4c4f3b7
("btrfsck: add code to rebuild extent records"), however it's not only
unused, but also used incorrectly.
It's calling btrfs_item_key_to_cpu() on an node extent buffer.
Anyway, just remove it.
Fixes: f5c4c4f3b7 ("btrfsck: add code to rebuild extent records")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For inline compressed file extent, kernel doesn't allow inline extent
ram size larger than sector size and on-disk inline extent size should
not exceed BTRFS_MAX_INLINE_DATA_SIZE().
For inline uncompressed file extent, kernel doesn't allow inline extent
ram and on-disk size larger than either BTRFS_MAX_INLINE_DATA_SIZE() or
sector size.
Check it in original mode.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Under some cases the filesystem checker reports an error when it finds
checksum items for an extent that is referenced by an inode as a prealloc
extent. Such cases are not an error when the extent is actually shared
(was cloned/reflinked) with other inodes and was written through one of
those other inodes.
Example:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ touch /mnt/foo
$ xfs_io -c "falloc 0 256K" /mnt/foo
$ sync
$ xfs_io -c "pwrite -S 0xab 0 256K" /mnt/foo
$ touch /mnt/bar
$ xfs_io -c "reflink /mnt/foo 0 0 256K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
<power fail>
$ mount /dev/sdb /mnt
$ umount /mnt
$ btrfs check /dev/sdc
Checking filesystem on /dev/sdb
UUID: 52d3006e-ee3b-40eb-aa21-e56253a03d39
checking extents
checking free space cache
checking fs roots
root 5 inode 257 errors 800, odd csum item
ERROR: errors found in fs roots
found 688128 bytes used, error(s) found
total csum bytes: 256
total tree bytes: 163840
total fs tree bytes: 65536
total extent tree bytes: 16384
btree space waste bytes: 138819
file data blocks allocated: 10747904
referenced 10747904
$ echo $?
1
So teach check to not report such cases as errors by checking if the
extent is shared with other inodes and if so, consider it an error the
existence of checksum items only if all those other inodes are referencing
the extent as a prealloc extent.
This case can be hit often when running the generic/475 testcase from
fstests.
A test case will follow in a separate patch.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs can delay inode deletion and in that case btrfs will unlink the
victim inode from its parent dir, and insert a marker to info btrfs to
delete it later.
In that case, such victim inode will have nlinks == 0, but is still
completely valid.
Original mode won't report such problem, but lowmem mode doesn't check
the ORPHAN_ITEM key for such inode, and can report false alert like:
------
ERROR: root 257 INODE[28891726] is orphan item
------
Fix such false alert by checking orphan item for inode whose nlink is 0.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs lowmem check reports the following false alert:
------
ERROR: file extent[267 2162688] root 256 owner 5 backref lost
------
The file extent is in the leaf which is shared by file tree 256 and fs
tree.
------
leaf 30605312 items 46 free space 4353 generation 7 owner 5
......
item 45 key (267 EXTENT_DATA 2162688) itemoff 5503 itemsize 53
generation 7 type 2 (prealloc)
prealloc data disk byte 13631488 nr 65536
prealloc data offset 32768 nr 32768
------
And there is the corresponding extent_data_ref item in the extent tree.
------
item 1 key (13631488 EXTENT_DATA_REF 1007496934287921081) itemoff 15274 itemsize 28
extent data backref root 5 objectid 267 offset 2129920 count 1
------
The offset of EXTENT_DATA_REF which is the hash of the owner root objectid,
the inode number and the calculated offset (file offset - extent offset).
What caused the false alert is the code mix up the owner root objectid and
the file tree objectid.
Fixes: b0d360b541 ("btrfs-progs: check: introduce function to check data backref in extent tree")
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Su Yanjun