Callers of alloc_test_extent_buffer have not correctly interpreted the
return value as error pointer, as alloc_test_extent_buffer should behave
as alloc_extent_buffer. The self-tests were unaffected but
btrfs_find_create_tree_block could call both functions and that would
cause problems up in the call chain.
Fixes: faa2dbf004 ("Btrfs: add sanity tests for new qgroup accounting code")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The type name is misleading, a single entry is named 'cache' while this
normally means a collection of objects. Rename that everywhere. Also the
identifier was quite long, making function prototypes harder to format.
Suggested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The on-disk format of block group item makes use of the key that stores
the offset and length. This is further used in the code, although this
makes thing harder to understand. The key is also packed so the
offset/length is not properly aligned as u64.
Add start (key.objectid) and length (key.offset) members to block group
and remove the embedded key. When the item is searched or written, a
local variable for key is used.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Some of the self tests create a test inode, setup some extents and then do
calls to btrfs_get_extent() to test that the corresponding extent maps
exist and are correct. However btrfs_get_extent(), since the 5.2 merge
window, now errors out when it finds a regular or prealloc extent for an
inode that does not correspond to a regular file (its ->i_mode is not
S_IFREG). This causes the self tests to fail sometimes, specially when
KASAN, slub_debug and page poisoning are enabled:
$ modprobe btrfs
modprobe: ERROR: could not insert 'btrfs': Invalid argument
$ dmesg
[ 9414.691648] Btrfs loaded, crc32c=crc32c-intel, debug=on, assert=on, integrity-checker=on, ref-verify=on
[ 9414.692655] BTRFS: selftest: sectorsize: 4096 nodesize: 4096
[ 9414.692658] BTRFS: selftest: running btrfs free space cache tests
[ 9414.692918] BTRFS: selftest: running extent only tests
[ 9414.693061] BTRFS: selftest: running bitmap only tests
[ 9414.693366] BTRFS: selftest: running bitmap and extent tests
[ 9414.696455] BTRFS: selftest: running space stealing from bitmap to extent tests
[ 9414.697131] BTRFS: selftest: running extent buffer operation tests
[ 9414.697133] BTRFS: selftest: running btrfs_split_item tests
[ 9414.697564] BTRFS: selftest: running extent I/O tests
[ 9414.697583] BTRFS: selftest: running find delalloc tests
[ 9415.081125] BTRFS: selftest: running find_first_clear_extent_bit test
[ 9415.081278] BTRFS: selftest: running extent buffer bitmap tests
[ 9415.124192] BTRFS: selftest: running inode tests
[ 9415.124195] BTRFS: selftest: running btrfs_get_extent tests
[ 9415.127909] BTRFS: selftest: running hole first btrfs_get_extent test
[ 9415.128343] BTRFS critical (device (efault)): regular/prealloc extent found for non-regular inode 256
[ 9415.131428] BTRFS: selftest: fs/btrfs/tests/inode-tests.c:904 expected a real extent, got 0
This happens because the test inodes are created without ever initializing
the i_mode field of the inode, and neither VFS's new_inode() nor the btrfs
callback btrfs_alloc_inode() initialize the i_mode. Initialization of the
i_mode is done through the various callbacks used by the VFS to create
new inodes (regular files, directories, symlinks, tmpfiles, etc), which
all call btrfs_new_inode() which in turn calls inode_init_owner(), which
sets the inode's i_mode. Since the tests only uses new_inode() to create
the test inodes, the i_mode was never initialized.
This always happens on a VM I used with kasan, slub_debug and many other
debug facilities enabled. It also happened to someone who reported this
on bugzilla (on a 5.3-rc).
Fix this by setting i_mode to S_IFREG at btrfs_new_test_inode().
Fixes: 6bf9e4bd6a ("btrfs: inode: Verify inode mode to avoid NULL pointer dereference")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204397
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since commit fee187d9d9 ("Btrfs: do not set EXTENT_DIRTY along with
EXTENT_DELALLOC"), we never set EXTENT_DIRTY in inode->io_tree, so we
can simplify and stop trying to clear it.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If any call to find_first_clear_extent_bit() returns an unexpected result,
the test should fail and not just print an error message, otherwise it
makes detection of regressions much harder to notice.
Fixes: 1eaebb341d ("btrfs: Don't trim returned range based on input value in find_first_clear_extent_bit")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The test creates an extent io tree and sets several ranges with the
CHUNK_ALLOCATED and CHUNK_TRIMMED bits, resulting in the allocation of
several extent state structures. However the test never clears those
ranges, resulting in memory leaks of the extent state structures.
This is detected when CONFIG_BTRFS_DEBUG is set once we remove the
btrfs module (rmmod btrfs):
[57399.787918] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.790155] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.791941] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
[57399.793753] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.795188] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.796453] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
[57399.797765] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.799049] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.800142] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
[57399.801126] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.802106] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.803119] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
[57399.804153] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.805196] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.806191] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
The start and end offsets reported correspond exactly to the ranges
used by the test.
So fix that by clearing all the ranges when the test finishes.
Fixes: 1eaebb341d ("btrfs: Don't trim returned range based on input value in find_first_clear_extent_bit")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is prep work for moving all of the block group cache code into its
own file.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
It's unlikely in-band dedupe is going to land so just remove any
leftovers - dedupe.h header as well as the 'dedupe' parameter to
btrfs_set_extent_delalloc.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull vfs mount updates from Al Viro:
"The first part of mount updates.
Convert filesystems to use the new mount API"
* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
mnt_init(): call shmem_init() unconditionally
constify ksys_mount() string arguments
don't bother with registering rootfs
init_rootfs(): don't bother with init_ramfs_fs()
vfs: Convert smackfs to use the new mount API
vfs: Convert selinuxfs to use the new mount API
vfs: Convert securityfs to use the new mount API
vfs: Convert apparmorfs to use the new mount API
vfs: Convert openpromfs to use the new mount API
vfs: Convert xenfs to use the new mount API
vfs: Convert gadgetfs to use the new mount API
vfs: Convert oprofilefs to use the new mount API
vfs: Convert ibmasmfs to use the new mount API
vfs: Convert qib_fs/ipathfs to use the new mount API
vfs: Convert efivarfs to use the new mount API
vfs: Convert configfs to use the new mount API
vfs: Convert binfmt_misc to use the new mount API
convenience helper: get_tree_single()
convenience helper get_tree_nodev()
vfs: Kill sget_userns()
...
Simplification. No point passing the tree variable when it can be
evaluated from inode. The tests now use the io_tree from btrfs_inode as
opposed to creating one.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are no concerns about locking during the selftests so the locks
are not necessary, but following patches will add lockdep assertions to
add_extent_mapping so this is needed in tests too.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently find_first_clear_extent_bit always returns a range whose
starting value is >= passed 'start'. This implicit trimming behavior is
somewhat subtle and an implementation detail.
Instead, this patch modifies the function such that now it always
returns the range which contains passed 'start' and has the given bits
unset. This range could either be due to presence of existing records
which contains 'start' but have the bits unset or because there are no
records that contain the given starting offset.
This patch also adds test cases which cover find_first_clear_extent_bit
since they were missing up until now.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Convert the btrfs_test filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.
See Documentation/filesystems/mount_api.txt for more information.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: David Sterba <dsterba@suse.com>
cc: Chris Mason <clm@fb.com>
cc: Josef Bacik <josef@toxicpanda.com>
cc: linux-btrfs@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Once upon a time we used to set ->d_name of e.g. pipefs root
so that d_path() on pipes would work. These days it's
completely pointless - dentries of pipes are not even connected
to pipefs root. However, mount_pseudo() had set the root
dentry name (passed as the second argument) and callers
kept inventing names to pass to it. Including those that
didn't *have* any non-root dentries to start with...
All of that had been pointless for about 8 years now; it's
time to get rid of that cargo-culting...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-----BEGIN PGP SIGNATURE-----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=fEkD
-----END PGP SIGNATURE-----
Merge tag 'for-5.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"This time the majority of changes are cleanups, though there's still a
number of changes of user interest.
User visible changes:
- better read time and write checks to catch errors early and before
writing data to disk (to catch potential memory corruption on data
that get checksummed)
- qgroups + metadata relocation: last speed up patch int the series
to address the slowness, there should be no overhead comparing
balance with and without qgroups
- FIEMAP ioctl does not start a transaction unnecessarily, this can
result in a speed up and less blocking due to IO
- LOGICAL_INO (v1, v2) does not start transaction unnecessarily, this
can speed up the mentioned ioctl and scrub as well
- fsync on files with many (but not too many) hardlinks is faster,
finer decision if the links should be fsynced individually or
completely
- send tries harder to find ranges to clone
- trim/discard will skip unallocated chunks that haven't been touched
since the last mount
Fixes:
- send flushes delayed allocation before start, otherwise it could
miss some changes in case of a very recent rw->ro switch of a
subvolume
- fix fallocate with qgroups that could lead to space accounting
underflow, reported as a warning
- trim/discard ioctl honours the requested range
- starting send and dedupe on a subvolume at the same time will let
only one of them succeed, this is to prevent changes that send
could miss due to dedupe; both operations are restartable
Core changes:
- more tree-checker validations, errors reported by fuzzing tools:
- device item
- inode item
- block group profiles
- tracepoints for extent buffer locking
- async cow preallocates memory to avoid errors happening too deep in
the call chain
- metadata reservations for delalloc reworked to better adapt in
many-writers/low-space scenarios
- improved space flushing logic for intense DIO vs buffered workloads
- lots of cleanups
- removed unused struct members
- redundant argument removal
- properties and xattrs
- extent buffer locking
- selftests
- use common file type conversions
- many-argument functions reduction"
* tag 'for-5.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (227 commits)
btrfs: Use kvmalloc for allocating compressed path context
btrfs: Factor out common extent locking code in submit_compressed_extents
btrfs: Set io_tree only once in submit_compressed_extents
btrfs: Replace clear_extent_bit with unlock_extent
btrfs: Make compress_file_range take only struct async_chunk
btrfs: Remove fs_info from struct async_chunk
btrfs: Rename async_cow to async_chunk
btrfs: Preallocate chunks in cow_file_range_async
btrfs: reserve delalloc metadata differently
btrfs: track DIO bytes in flight
btrfs: merge calls of btrfs_setxattr and btrfs_setxattr_trans in btrfs_set_prop
btrfs: delete unused function btrfs_set_prop_trans
btrfs: start transaction in xattr_handler_set_prop
btrfs: drop local copy of inode i_mode
btrfs: drop old_fsflags in btrfs_ioctl_setflags
btrfs: modify local copy of btrfs_inode flags
btrfs: drop useless inode i_flags copy and restore
btrfs: start transaction in btrfs_ioctl_setflags()
btrfs: export btrfs_set_prop
btrfs: refactor btrfs_set_props to validate externally
...
We can read fs_info from the block group cache structure and can drop it
from the parameters. Though the transaction is also availabe, it's not
guaranteed to be non-NULL.
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
When accessing a file on a crafted image, btrfs can crash in block layer:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
PGD 136501067 P4D 136501067 PUD 124519067 PMD 0
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.0.0-rc8-default #252
RIP: 0010:end_bio_extent_readpage+0x144/0x700
Call Trace:
<IRQ>
blk_update_request+0x8f/0x350
blk_mq_end_request+0x1a/0x120
blk_done_softirq+0x99/0xc0
__do_softirq+0xc7/0x467
irq_exit+0xd1/0xe0
call_function_single_interrupt+0xf/0x20
</IRQ>
RIP: 0010:default_idle+0x1e/0x170
[CAUSE]
The crafted image has a tricky corruption, the INODE_ITEM has a
different type against its parent dir:
item 20 key (268 INODE_ITEM 0) itemoff 2808 itemsize 160
generation 13 transid 13 size 1048576 nbytes 1048576
block group 0 mode 121644 links 1 uid 0 gid 0 rdev 0
sequence 9 flags 0x0(none)
This mode number 0120000 means it's a symlink.
But the dir item think it's still a regular file:
item 8 key (264 DIR_INDEX 5) itemoff 3707 itemsize 32
location key (268 INODE_ITEM 0) type FILE
transid 13 data_len 0 name_len 2
name: f4
item 40 key (264 DIR_ITEM 51821248) itemoff 1573 itemsize 32
location key (268 INODE_ITEM 0) type FILE
transid 13 data_len 0 name_len 2
name: f4
For symlink, we don't set BTRFS_I(inode)->io_tree.ops and leave it
empty, as symlink is only designed to have inlined extent, all handled
by tree block read. Thus no need to trigger btrfs_submit_bio_hook() for
inline file extent.
However end_bio_extent_readpage() expects tree->ops populated, as it's
reading regular data extent. This causes NULL pointer dereference.
[FIX]
This patch fixes the problem in two ways:
- Verify inode mode against its dir item when looking up inode
So in btrfs_lookup_dentry() if we find inode mode mismatch with dir
item, we error out so that corrupted inode will not be accessed.
- Verify inode mode when getting extent mapping
Only regular file should have regular or preallocated extent.
If we found regular/preallocated file extent for symlink or
the rest, we error out before submitting the read bio.
With this fix that crafted image can be rejected gracefully:
BTRFS critical (device loop0): inode mode mismatch with dir: inode mode=0121644 btrfs type=7 dir type=1
Reported-by: Yoon Jungyeon <jungyeon@gatech.edu>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=202763
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The commit fcebe4562d ("Btrfs: rework qgroup accounting") reworked
qgroups and added some new structures. Another rework of qgroup
mechanics e69bcee376 ("btrfs: qgroup: Cleanup the old
ref_node-oriented mechanism.") stopped using them and left uncleaned.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The messages like 'extent I/O tests finished' are redundant, if the test
fails it's quite obvious in the log and hang is also noticeable. No
other then extent_io and free space tree tests print that so make it
consistent.
Signed-off-by: David Sterba <dsterba@suse.com>
Comments about ranges did not match the code, the correct calculation is
to use start and start+len as the interval boundaries.
Signed-off-by: David Sterba <dsterba@suse.com>
The way the extent map tests handle errors does not conform to the rest
of the suite, where the first failure is reported and then it stops.
Do the same now that we have the errors returned from all the functions.
Signed-off-by: David Sterba <dsterba@suse.com>
The individual testcases for extent maps do not return an error on
allocation failures. This is not a big problem as the allocation don't
fail in general but there are functional tests handled with ASSERTS.
This makes tests dependent on them and it's not reliable.
This patch adds the allocation failure handling and allows for the
conversion of the asserts to proper error handling and reporting.
Signed-off-by: David Sterba <dsterba@suse.com>
Allocation of main objects like fs_info or extent buffers is in each
test so let's simplify and unify the error messages to a table and add a
convenience helper.
Signed-off-by: David Sterba <dsterba@suse.com>
For better diagnostics print the file name and line to locate the
errors. Sample output:
[ 9.052924] BTRFS: selftest: fs/btrfs/tests/extent-io-tests.c:283 offset bits do not match
Signed-off-by: David Sterba <dsterba@suse.com>
The fs_info is not freed at the end of the function and leaks. The
function is called twice so there can be up to 2x sizeof(struct
btrfs_fs_info) of leaked memory. Fortunatelly this affects only testing
builds, the size could be 16k with several debugging features enabled.
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs has the following different extent_io_trees used:
- fs_info::free_extents[2]
- btrfs_inode::io_tree - for both normal inodes and the btree inode
- btrfs_inode::io_failure_tree
- btrfs_transaction::dirty_pages
- btrfs_root::dirty_log_pages
If we want to trace changes in those trees, it will be pretty hard to
distinguish them.
Instead of using hard-to-read pointer address, this patch will introduce
a new member extent_io_tree::owner to track the owner.
This modification needs all the callers of extent_io_tree_init() to
accept a new parameter @owner.
This patch provides the basis for later trace events.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch will add a new member fs_info to extent_io_tree.
This provides the basis for later trace events to distinguish the output
between different btrfs filesystems. While this increases the size of
the structure, we want to know the source of the trace events and
passing the fs_info as an argument to all contexts is not possible.
The selftests are now allowed to set it to NULL as they don't use the
tracepoints.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The @found is always false when it comes to the if branch. Besides, the
bool type is more suitable for @found. Change the return value of the
function and its caller to bool as well.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Several functions in BTRFS are only used inside the source file they are
declared if CONFIG_BTRFS_FS_RUN_SANITY_TESTS is not defined. However if
CONFIG_BTRFS_FS_RUN_SANITY_TESTS is defined these functions are shared
with the unit tests code.
Before the introduction of the EXPORT_FOR_TESTS macro, these functions
could not be declared as static and the compiler had a harder task when
optimizing and inlining them.
As we have EXPORT_FOR_TESTS now, use it where appropriate to support the
compiler.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All callers of this function pass BTRFS_MAX_EXTENT_SIZE (128M) so let's
reduce the argument count and make that a local variable. No functional
changes.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The loop construct in free_extent_buffer was added in
242e18c7c1 ("Btrfs: reduce lock contention on extent buffer locks")
as means of reducing the times the eb lock is taken, the non-last ref
count is decremented and lock is released. As the special handling
of UNMAPPED extent buffers was removed now there is only one decrement
op which is happening for EXTENT_BUFFER_UNMAPPED case.
This commit modifies the loop condition so that in case of UNMAPPED
buffers the eb's lock is taken only if we are 100% sure the eb is going
to be freed by the current executor of the code. Additionally, remove
superfluous ref count ops in btrfs test.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that the whole of btrfs code has been audited for eb reference count
management it's time to remove the hunk in free_extent_buffer that
essentially considered the condition
"eb->ref == 2 && EXTENT_BUFFER_DUMMY"
to equal "eb->ref = 1". Also remove the last location
which takes an extra reference count in alloc_test_extent_buffer.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In extent-io self test, we need 2 ordered extents at its maximum size to
do the test.
Instead of using the intermediate numbers, use BTRFS_MAX_EXTENT_SIZE for
@max_bytes, and twice @max_bytes for @total_dirty. This should explain
why we need all these magic numbers and prevent people to modify them by
accident.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
