Commit Graph

161 Commits

Author SHA1 Message Date
Rosen Penev
5d72055066 btrfs-progs: Fix printf formats
Discovered with cppcheck. Fix signed/unsigned int mismatches, sizeof and
long formats.

Pull-request: #197
Signed-off-by: Rosen Penev <rosenp@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-14 17:31:05 +02:00
Johannes Thumshirn
ed33908b44 btrfs-progs: update checksumming api
Update the checksumming API to be able to cope with more checksum types
than just CRC32C. The finalization call is merged into btrfs_csum_data.

There are some fixme's and asserts added that need to be resolved.

Co-developed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-14 17:28:34 +02:00
Johannes Thumshirn
7b4f1035a6 btrfs-progs: pass checksum type to btrfs_csum_data()/btrfs_csum_final()
In preparation to supporting new checksum algorithm pass the checksum type
to btrfs_csum_data/btrfs_csum_final, this allows us to encapsulate any
differences in processing into the respective functions

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-14 17:28:28 +02:00
Johannes Thumshirn
de68086e35 btrfs-progs: don't assume checksums are always 4 bytes
Pass pointer to a generic buffer instead of fixed size that crc32c
currently uses.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-14 17:28:25 +02:00
David Sterba
0889161127 btrfs-progs: check: move device_record to main.c
The structure is used only inside main.c, no need to export it.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-14 17:27:41 +02:00
David Sterba
705f4ecf02 btrfs-progs: check: remove flat include switch from common.h
The header will be used only internally, so the FLAT_INCLUDES is not
needed.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-14 17:27:39 +02:00
David Sterba
1b42e71053 btrfs-progs: copy btrfsck.h to check/common.h
We want just one header for the check API (similar to what mkfs does)
but as btrfsck.h is exported header (libbtrfs), it needs some
deprecation beriod before it's moved through there are probably no users
of that header file in particular.

Copy the header to check, all modifications and cleanups won't affect
the public header.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-14 17:27:37 +02:00
David Sterba
8e68287d88 btrfs-progs: move qgroup-verify.[ch] to check/
The only user of the functionality is in check.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-14 17:27:35 +02:00
Qu Wenruo
c31bd8db54 btrfs-progs: check/lowmem: Skip nbytes check for orphan inodes
For orphan inodes, kernel won't update its nbytes and size since it's a
waste of time.

So lowmem check can report false alert on some orphan inodes.

Fix it by checking if the inode is an orphan before
complaining/repairing its nbytes.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-04 16:08:56 +02:00
Josef Bacik
73ff25c65d btrfs-progs: check: don't check nbytes on unlinked files
We don't update the inode when evicting it, so the nbytes will be wrong
in between transaction commits.  This isn't a problem, stop complaining
about it to make generic/269 stop randomly failing. The orphan outdated
inodes can be still present but check will not skip them.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-04 16:08:11 +02:00
Qu Wenruo
1baf729743 btrfs-progs: check/original: Check and repair root item geneartion
Add such ability to original mode to fix root generation mismatch, which
can be rejected by kernel.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-04 16:06:52 +02:00
Qu Wenruo
ebf29e39c3 btrfs-progs: check/lowmem: Check and repair root generation
Since kernel is going to reject any root item which is newer than super
block generation, we need to provide a way to fix such problem in
btrfs-check.

This patch addes the ability to report and repair root generation in
lowmem mode.

This is done by cowing the root node, so we will update the root
generation along with the root node generation at commit transaction
time.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-04 16:06:50 +02:00
Adam Borowski
90a87e817d btrfs-progs: check: fix option parsing for -E
The option -E has a mandatory argument that was missing from the short
option spec, thus it always crashed.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-04 16:06:24 +02:00
Naohiro Aota
8ca6c0c3c7 btrfs-progs: check: initialize qgroup_item_count in earlier stage
"btrfsck -Q" segfaults because it does not call qgroup_set_item_count_ptr()
properly:

  # btrfsck -Q /dev/sdk
  Opening filesystem to check...
  Checking filesystem on /dev/sdk
  UUID: 34a35bbc-43f8-40f0-8043-65ed33f2e6c3
  Print quota groups for /dev/sdk
  UUID: 34a35bbc-43f8-40f0-8043-65ed33f2e6c3
  Segmentation fault (core dumped)

Since "struct task_ctx ctx" is global, we can just move
qgroup_set_item_count_ptr() much earlier stage in the check process to
avoid to forget initializing it.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-26 17:46:42 +02:00
Josef Bacik
42a1aaeec4 btrfs-progs: deal with drop_progress properly in fsck
While testing snapshot deletion with dm-log-writes I saw that I was
failing the fsck sometimes when the fs was actually in the correct
state.  This is because we only skip blocks on the same level of
root_item->drop_level.  If the drop_level < the root level then we could
very well walk into nodes that we wouldn't actually walk into on fs
mount, because the drop_progress is further ahead in the slot of the
root.  Instead only process the slots of the nodes that are above the
drop_progress key.  With this patch in place we no longer improperly
fail to check fs'es that have a drop_progress set with a drop_level <
root level.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-26 17:46:42 +02:00
David Sterba
c8bea2b84b btrfs-progs: move rbtree-utils.[ch] to common/
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 20:49:04 +02:00
David Sterba
c07960c8be btrfs-progs: move utils.[ch] to common/
Update include paths and remove some duplicates.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 20:49:04 +02:00
David Sterba
aac564aca6 btrfs-progs: move commonh to common/
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 20:49:03 +02:00
David Sterba
f93b471143 btrfs-progs: move help.[ch] to common/
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 20:49:03 +02:00
David Sterba
d0970a05cd btrfs-progs: move task-utils.[ch] to common/
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 20:49:03 +02:00
David Sterba
d1efe50d0a btrfs-progs: move messages.[ch] to common/
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 20:49:03 +02:00
David Sterba
f63f29e9e9 btrfs-progs: move internal.h to common/
Create directory for all sources that can be used by anything that's not
rellated to a relevant kernel part, all common functions, helpers,
utilities that do not fit any other specific category.

The traditional location would be probably lib/ with all things that are
statically linked to the main binaries, but we have libbtrfs and
libbtrfsutil so this would be confusing.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 20:49:03 +02:00
Nikolay Borisov
32f75c87a0 btrfs-progs: check: Remove duplicated and commented functions
Commit 756105181e ("btrfs-progs: check: supplement extent backref
list with rbtree") changed the backref implementation to use rb tree
and also commented the old implementations. It's been almost 2 years
since that change and it's unlikely the old version will ever be used,
so just remove it.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 13:31:16 +02:00
Jeff Mahoney
91a1476d53 btrfs-progs: pass cmd_struct to usage()
Now that every call site has a cmd_struct, we can just pass the cmd_struct
to usage to print the usager information.  This allows us to interpret
the format flags we'll add later in this series to inform the user of
which output formats any given command supports.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 13:31:15 +02:00
Jeff Mahoney
b44445131f btrfs-progs: pass cmd_struct to command callback function
This patch passes the cmd_struct to the command callback function.  This
has several purposes: It allows the command callback to identify which
command was used to call it.  It also gives us direct access to the
usage associated with that command.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 13:31:15 +02:00
Jeff Mahoney
82d48463ea btrfs-progs: use cmd_struct as command entry point
Rather than having global command usage and callbacks used to create
cmd_structs in the command array, establish the cmd_struct structures
separately and use those.  The next commit in the series passes the
cmd_struct to the command callbacks such that we can access flags
and determine which of several potential command we were called as.

This establishes several macros to more easily define the commands
within each command's source.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-03 13:31:15 +02:00
Qu Wenruo
48248693cd btrfs-progs: check/lowmem: Reset path in repair mode to avoid incorrect item from being passed to lowmem check.
In lowmem mode, we check fs roots and free space cache by iterating
each root item and inode item, using btrfs_next_item() and a path
pointing to the root tree.

However in repair mode, check_fs_root() can modify the fs root, thus
CoWs the tree root, and the old path in check_fs

It could lead to strange behavior, e.g. after repairing a fs tree, the
path can point to a fs tree.
Since no ROOT_ITEM exists in fs tree, all remaining trees are skipped in
repair mode.

This bug exists from the early time of lowmem mode repair, and is only
exposed by recent free space inode check code. (Fs tree inodes are
passed to free space inode check, causing false alerts and repair
failure).

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-06-05 18:02:05 +02:00
Qu Wenruo
085445e793 btrfs-progs: Cleanup BTRFS_COMPAT_EXTENT_TREE_V0
BTRFS_COMPAT_EXTENT_TREE_V0 is introduced for a short time in kernel,
and it's over 10 years ago.

Nowadays there should be no user for that feature, and kernel has remove
this support in Jun, 2018. There is no need for btrfs-progs to support
it.

This patch will remove EXTENT_TREE_V0 related code and replace those
BUG_ON() to a more graceful error message.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-06-05 18:00:07 +02:00
Qu Wenruo
d73427b76d btrfs-progs: check/original: Add checks for compressed extent without csum
There is one report of compressed extent happens in btrfs, but has no
csum and then leads to possible decompress error screwing up kernel
memory.

Although it's a kernel bug, and won't cause problem until compressed
data get corrupted, let's catch such problem in advance.

This patch will catch any unexpected compressed extent with:

1) 0 or less than expected csum

2) nodatasum flag set in the inode item

This is for original mode.

Reported-by: James Harvey <jamespharvey20@gmail.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-05-17 12:32:38 +02:00
Qu Wenruo
cc7a35f642 btrfs-progs: check/lowmem: Add checks for compressed extent without csum
There is one report of compressed extent happens in btrfs, but has no
csum and then leads to possible decompress error screwing up kernel
memory.

Although it's a kernel bug, and won't cause problem until compressed
data get corrupted, let's catch such problem in advance.

This patch will catch any unexpected compressed extent with:

1) missing csum

2) nodatasum flag set in the inode item

This is for lowmem mode.

Reported-by: James Harvey <jamespharvey20@gmail.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-05-17 12:32:38 +02:00
Jeff Mahoney
50faf73f22 btrfs-progs: check: fixup_extent_flags needs to deal with non-skinny metadata
When repairing a file system created by a very old kernel, I ran into
issues fixing up the extent flags since fixup_extent_flags assumed
that a METADATA_ITEM would be present if the record was for metadata.

Since METADATA_ITEMs don't exist without skinny metadata, we need to
fall back to EXTENT_ITEMs.  This also falls back to EXTENT_ITEMs even
with skinny metadata enabled as other parts of the tools do.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-05-17 12:32:38 +02:00
Qu Wenruo
427990ad74 btrfs-progs: check/original: Check and repair free space cache inode item
Just like lowmem mode, also check and repair free space cache inode
item.

And since we don't really have a good timing/function to check free
space chace inodes, we use the same common mode
check_repair_free_space_inode() when iterating root tree.

Signed-off-by: Qu Wenruo <wqu@suse.com>
2019-04-16 09:04:25 +08:00
Qu Wenruo
77fe19ba16 btrfs-progs: check/lowmem: Check and repair free space cache inode mode
Unlike inodes in fs roots, we don't really check the inode items in root
tree, in fact we just skip everything other than ROOT_ITEM and ROOT_REF.

This makes invalid inode items sneak into root tree.
For example:
        item 9 key (256 INODE_ITEM 0) itemoff 13702 itemsize 160
                generation 30 transid 30 size 65536 nbytes 1507328
                block group 0 mode 0 links 1 uid 0 gid 0 rdev 0
				   ^ Should be 100600
                sequence 23 flags 0x1b(NODATASUM|NODATACOW|NOCOMPRESS|PREALLOC)
                atime 0.0 (1970-01-01 08:00:00)
                ctime 1553491158.189771625 (2019-03-25 13:19:18)
                mtime 0.0 (1970-01-01 08:00:00)
                otime 0.0 (1970-01-01 08:00:00)

There is a report of such problem in the mail list.

This patch will check and repair inode items of free space cache inodes in
lowmem mode.

Since free space cache inodes doesn't have INODE_REF but still has 1
link, we can't use check_inode_item() directly.
Instead we only check the inode mode, as that's the important part.

The check and repair function: check_repair_free_space_inode() is also
exported for original mode.

Signed-off-by: Qu Wenruo <wqu@suse.com>
2019-04-16 09:04:25 +08:00
Qu Wenruo
11fd6cff82 btrfs-progs: check/original: Repair invalid inode mode in root tree
This patch will reuse the mode independent repair_imode() function, to
repair invalid inode mode.

Signed-off-by: Qu Wenruo <wqu@suse.com>
2019-04-16 09:04:25 +08:00
Qu Wenruo
64ca43a8ad btrfs-progs: check/lowmem: Repair invalid inode mode in root tree
In root tree, we only have 2 types of inodes:
- ROOT_TREE_DIR inode
  Its mode is fixed to 40755
- free space cache inodes
  Its mode is fixed to 100600

This patch will add the ability to repair such inodes to lowmem mode.
For fs/subvolume tree error, at least we haven't see such corruption
yet, so we don't need to rush to fix corruption in fs trees yet.

The repair function, reset_imode() and repair_imode_common() can be
reused by later original mode patch, so it's placed in check/mode-common.c.

Signed-off-by: Qu Wenruo <wqu@suse.com>
2019-04-16 09:04:25 +08:00
Qu Wenruo
23f1e9a13f btrfs-progs: check/original: Add inode mode check
Just like lowmem mode, check inode mode, specially for S_IFMT bits and
beyond.

Please note that, this check only applies to inodes in fs/subvol trees.
It doesn't apply to free space cache inodes.

Reported-by: Thorsten Hirsch <t.hirsch@web.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
2019-04-16 09:04:25 +08:00
Qu Wenruo
c06c5eef88 btrfs-progs: check/lowmem: Add inode mode check
There is one report about invalid free space cache inode mode.
Normally free space cache inode should have mode 100600 (regular file,
no uid/gid/sticky bit, rw------ bit).

But in that report, we have free space cache inode mode as 0.

So at least btrfs check should report invalid inode mode.

This patch will at least make btrfs check lowmem mode to detect this
problem.

Please note that, this check only applies to inodes in fs/subvol trees.
It doesn't apply to free space cache inodes.

Reported-by: Thorsten Hirsch <t.hirsch@web.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
2019-04-16 09:04:25 +08:00
Qu Wenruo
db51d8d8f6 btrfs-progs: Use @fs_info to replace @root for btrfs_check_leaf/node()
Signed-off-by: Qu Wenruo <wqu@suse.com>
2019-04-16 09:04:25 +08:00
Su Yanjun
cedbfc2561 btrfs-progs: check: Delete file extent item with unaligned disk bytenr
For test case fsck-tests/001-bad-file-extent-bytenr, we have an
obviously hand crafted image with unaligned file extent:

        item 7 key (257 EXTENT_DATA 0) itemoff 3453 itemsize 53
                generation 6 type 1 (regular)
                extent data disk byte 755944791 nr 1048576
                extent data offset 0 nr 1048576 ram 1048576
                extent compression 0 (none)

disk bytenr 755944791 is obviously unaligned (not even).

For such obviously corrupted file extent, we should just delete the file
extent.

Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
[Update commit message and comment]
Signed-off-by: Qu Wenruo <wqu@suse.com>
2019-04-16 09:04:25 +08:00
Su Yanjun
3b35deeadd btrfs-progs: check: fix wrong @offset used in find_possible_backrefs()
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>
2019-04-16 09:04:25 +08:00
Su Yanjun
b6a0d97cba Revert "btrfs-progs: Record orphan data extent ref to corresponding root."
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>
2019-04-16 09:03:51 +08:00
Su Yanjun
872c116c75 Revert "btrfs-progs: Add repair and report function for orphan file extent."
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>
2019-04-16 09:03:02 +08:00
Su Yue
0617bde3bc btrfs-progs: lowmem: delete unaligned bytes extent data under repair
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>
2019-04-16 09:02:13 +08:00
Su Yue
a170ef86ff btrfs-progs: lowmem: rename delete_extent_tree_item() to delete_item()
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>
2019-04-16 09:02:09 +08:00
Su Yue
2a058a2204 btrfs-progs: lowmem: check unaligned disk_bytenr for extent_data
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>
2019-04-16 09:02:08 +08:00
Su Yue
cbe66f5804 btrfs-progs: lowmem: fix false alert if extent item has been repaired
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>
2019-04-16 09:02:06 +08:00
Su Yue
0ea38ae08d btrfs-progs: lowmem: move nbytes check before isize check
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>
2019-04-16 09:02:04 +08:00
Su Yue
ee455db07e btrfs-progs: lowmem: add argument path to punch_extent_hole()
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>
2019-04-16 09:02:01 +08:00
Lu Fengqi
fa13420cc7 btrfs-progs: lowmem: fix false alert about the existence of gaps in the check_file_extent
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>
2019-04-16 09:01:53 +08:00
Qu Wenruo
e76fb663a7 btrfs-progs: check: Fix false alert about uninitialized variable
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>
2019-03-05 12:57:41 +01:00