fscrypt currently only supports AES encryption. However, many low-end
mobile devices have older CPUs that don't have AES instructions, e.g.
the ARMv8 Cryptography Extensions. Currently, user data on such devices
is not encrypted at rest because AES is too slow, even when the NEON
bit-sliced implementation of AES is used. Unfortunately, it is
infeasible to encrypt these devices at all when AES is the only option.
Therefore, this patch updates fscrypt to support the Speck block cipher,
which was recently added to the crypto API. The C implementation of
Speck is not especially fast, but Speck can be implemented very
efficiently with general-purpose vector instructions, e.g. ARM NEON.
For example, on an ARMv7 processor, we measured the NEON-accelerated
Speck128/256-XTS at 69 MB/s for both encryption and decryption, while
AES-256-XTS with the NEON bit-sliced implementation was only 22 MB/s
encryption and 19 MB/s decryption.
There are multiple variants of Speck. This patch only adds support for
Speck128/256, which is the variant with a 128-bit block size and 256-bit
key size -- the same as AES-256. This is believed to be the most secure
variant of Speck, and it's only about 6% slower than Speck128/128.
Speck64/128 would be at least 20% faster because it has 20% rounds, and
it can be even faster on CPUs that can't efficiently do the 64-bit
operations needed for Speck128. However, Speck64's 64-bit block size is
not preferred security-wise. ARM NEON also supports the needed 64-bit
operations even on 32-bit CPUs, resulting in Speck128 being fast enough
for our targeted use cases so far.
The chosen modes of operation are XTS for contents and CTS-CBC for
filenames. These are the same modes of operation that fscrypt defaults
to for AES. Note that as with the other fscrypt modes, Speck will not
be used unless userspace chooses to use it. Nor are any of the existing
modes (which are all AES-based) being removed, of course.
We intentionally don't make CONFIG_FS_ENCRYPTION select
CONFIG_CRYPTO_SPECK, so people will have to enable Speck support
themselves if they need it. This is because we shouldn't bloat the
FS_ENCRYPTION dependencies with every new cipher, especially ones that
aren't recommended for most users. Moreover, CRYPTO_SPECK is just the
generic implementation, which won't be fast enough for many users; in
practice, they'll need to enable CRYPTO_SPECK_NEON to get acceptable
performance.
More details about our choice of Speck can be found in our patches that
added Speck to the crypto API, and the follow-on discussion threads.
We're planning a publication that explains the choice in more detail.
But briefly, we can't use ChaCha20 as we previously proposed, since it
would be insecure to use a stream cipher in this context, with potential
IV reuse during writes on f2fs and/or on wear-leveling flash storage.
We also evaluated many other lightweight and/or ARX-based block ciphers
such as Chaskey-LTS, RC5, LEA, CHAM, Threefish, RC6, NOEKEON, SPARX, and
XTEA. However, all had disadvantages vs. Speck, such as insufficient
performance with NEON, much less published cryptanalysis, or an
insufficient security level. Various design choices in Speck make it
perform better with NEON than competing ciphers while still having a
security margin similar to AES, and in the case of Speck128 also the
same available security levels. Unfortunately, Speck does have some
political baggage attached -- it's an NSA designed cipher, and was
rejected from an ISO standard (though for context, as far as I know none
of the above-mentioned alternatives are ISO standards either).
Nevertheless, we believe it is a good solution to the problem from a
technical perspective.
Certain algorithms constructed from ChaCha or the ChaCha permutation,
such as MEM (Masked Even-Mansour) or HPolyC, may also meet our
performance requirements. However, these are new constructions that
need more time to receive the cryptographic review and acceptance needed
to be confident in their security. HPolyC hasn't been published yet,
and we are concerned that MEM makes stronger assumptions about the
underlying permutation than the ChaCha stream cipher does. In contrast,
the XTS mode of operation is relatively well accepted, and Speck has
over 70 cryptanalysis papers. Of course, these ChaCha-based algorithms
can still be added later if they become ready.
The best known attack on Speck128/256 is a differential cryptanalysis
attack on 25 of 34 rounds with 2^253 time complexity and 2^125 chosen
plaintexts, i.e. only marginally faster than brute force. There is no
known attack on the full 34 rounds.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently the key derivation function in fscrypt uses the master key
length as the amount of output key material to derive. This works, but
it means we can waste time deriving more key material than is actually
used, e.g. most commonly, deriving 64 bytes for directories which only
take a 32-byte AES-256-CTS-CBC key. It also forces us to validate that
the master key length is a multiple of AES_BLOCK_SIZE, which wouldn't
otherwise be necessary.
Fix it to only derive the needed length key.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Refactor the confusingly-named function 'validate_user_key()' into a new
function 'find_and_derive_key()' which first finds the keyring key, then
does the key derivation. Among other benefits this avoids the strange
behavior we had previously where if key derivation failed for some
reason, then we would fall back to the alternate key prefix. Now, we'll
only fall back to the alternate key prefix if a valid key isn't found.
This patch also improves the warning messages that are logged when the
keyring key's payload is invalid.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Use a common function for fscrypt warning and error messages so that all
the messages are consistently ratelimited, include the "fscrypt:"
prefix, and include the filesystem name if applicable.
Also fix up a few of the log messages to be more descriptive.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
With one exception, the internal key size constants such as
FS_AES_256_XTS_KEY_SIZE are only used for the 'available_modes' array,
where they really only serve to obfuscate what the values are. Also
some of the constants are unused, and the key sizes tend to be in the
names of the algorithms anyway. In the past these values were also
misused, e.g. we used to have FS_AES_256_XTS_KEY_SIZE in places that
technically should have been FS_MAX_KEY_SIZE.
The exception is that FS_AES_128_ECB_KEY_SIZE is used for key
derivation. But it's more appropriate to use
FS_KEY_DERIVATION_NONCE_SIZE for that instead.
Thus, just put the sizes directly in the 'available_modes' array.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We're passing 'key_type_logon' to request_key(), so the found key is
guaranteed to be of type "logon". Thus, there is no reason to check
later that the key is really a "logon" key.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now ->max_namelen() is only called to limit the filename length when
adding NUL padding, and only for real filenames -- not symlink targets.
It also didn't give the correct length for symlink targets anyway since
it forgot to subtract 'sizeof(struct fscrypt_symlink_data)'.
Thus, change ->max_namelen from a function to a simple 'unsigned int'
that gives the filesystem's maximum filename length.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fname_decrypt() is validating that the encrypted filename is nonempty.
However, earlier a stronger precondition was already enforced: the
encrypted filename must be at least 16 (FS_CRYPTO_BLOCK_SIZE) bytes.
Drop the redundant check for an empty filename.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fname_decrypt() returns an error if the input filename is longer than
the inode's ->max_namelen() as given by the filesystem. But, this
doesn't actually make sense because the filesystem provided the input
filename in the first place, where it was subject to the filesystem's
limits. And fname_decrypt() has no internal limit itself.
Thus, remove this unnecessary check.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In fscrypt_setup_filename(), remove the unnecessary check for
fscrypt_get_encryption_info() returning EOPNOTSUPP. There's no reason
to handle this error differently from any other. I think there may have
been some confusion because the "notsupp" version of
fscrypt_get_encryption_info() returns EOPNOTSUPP -- but that's not
applicable from inside fs/crypto/.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fscrypt is clearing the flags on the crypto_skcipher it allocates for
each inode. But, this is unnecessary and may cause problems in the
future because it will even clear flags that are meant to be internal to
the crypto API, e.g. CRYPTO_TFM_NEED_KEY.
Remove the unnecessary flag clearing.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
skcipher_request_alloc() can only fail due to lack of memory, and in
that case the memory allocator will have already printed a detailed
error message. Thus, remove the redundant error messages from fscrypt.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
crypto_alloc_skcipher() returns an ERR_PTR() on failure, not NULL.
Remove the unnecessary check for NULL.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now that all filesystems have been converted to use
fscrypt_prepare_lookup(), we can remove the fscrypt_set_d_op() and
fscrypt_set_encrypted_dentry() functions as well as un-export
fscrypt_d_ops.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Improve fscrypt read performance by switching the decryption workqueue
from bound to unbound. With the bound workqueue, when multiple bios
completed on the same CPU, they were decrypted on that same CPU. But
with the unbound queue, they are now decrypted in parallel on any CPU.
Although fscrypt read performance can be tough to measure due to the
many sources of variation, this change is most beneficial when
decryption is slow, e.g. on CPUs without AES instructions. For example,
I timed tarring up encrypted directories on f2fs. On x86 with AES-NI
instructions disabled, the unbound workqueue improved performance by
about 25-35%, using 1 to NUM_CPUs jobs with 4 or 8 CPUs available. But
with AES-NI enabled, performance was unchanged to within ~2%.
I also did the same test on a quad-core ARM CPU using xts-speck128-neon
encryption. There performance was usually about 10% better with the
unbound workqueue, bringing it closer to the unencrypted speed.
The unbound workqueue may be worse in some cases due to worse locality,
but I think it's still the better default. dm-crypt uses an unbound
workqueue by default too, so this change makes fscrypt match.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We don't need to wait for whole bunch of discard candidates in fstrim, since
runtime discard will issue them in idle time.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In order to avoid interfering normal r/w IO, let's turn down IO
priority of discard issued from background.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Now, we issue discard asynchronously in separated thread instead of in
checkpoint, after that, we won't encounter long latency in checkpoint
due to huge number of synchronous discard command handling, so, we don't
need to split checkpoint to do trim in batch, merge it and obsolete
related sysfs entry.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In the high utilization like over 80%, we don't expect huge # of large discard
commands, but do many small pending discards which affects FTL GCs a lot.
Let's issue them in that case.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
For non-atomic files, this patch adds an option to give nobarrier which
doesn't issue flush commands to the device.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The fstrim gathers huge number of large discard commands, and tries to issue
without IO awareness, which results in long user-perceive IO latencies on
READ, WRITE, and FLUSH in UFS. We've observed some of commands take several
seconds due to long discard latency.
This patch limits the maximum size to 2MB per candidate, and check IO congestion
when issuing them to disk.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
pageout() in MM traslates EAGAIN, so calls handle_write_error()
-> mapping_set_error() -> set_bit(AS_EIO, ...).
file_write_and_wait_range() will see EIO error, which is critical
to return value of fsync() followed by atomic_write failure to user.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch clears PageError in some pages tagged by read path, but when we
write the pages with valid contents, writepage should clear the bit likewise
ext4.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch changes the rule to check cap_resource for data blocks, not inode
or node blocks in order to avoid selinux denial.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch reverts copied f2fs_set_page_dirty_nobuffer to use generic function
for stability.
This reverts commit fe76b796fc5194cc3d57265002e3a748566d073f.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch clears PageError in some pages tagged by read path, but when we
write the pages with valid contents, writepage should clear the bit likewise
ext4.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
xfstest generic/429 sometimes hangs on f2fs, caused by a thread being
unable to take a directory's i_rwsem for write in vfs_rmdir(). In the
test, one thread repeatedly creates and removes a directory, and other
threads repeatedly look up a file in the directory. The bug is that
f2fs_mkdir() calls d_instantiate() before unlock_new_inode(), resulting
in the directory inode being exposed to lookups before it has been fully
initialized. And with CONFIG_DEBUG_LOCK_ALLOC, unlock_new_inode()
reinitializes ->i_rwsem, corrupting its state when it is already held.
Fix it by calling unlock_new_inode() before d_instantiate(). This
matches what other filesystems do.
Fixes: 57397d86c6 ("f2fs: add inode operations for special inodes")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Currently f2fs's ->readpage() and ->readpages() assume that either the
data undergoes no postprocessing, or decryption only. But with
fs-verity, there will be an additional authenticity verification step,
and it may be needed either by itself, or combined with decryption.
To support this, store a 'struct bio_post_read_ctx' in ->bi_private
which contains a work struct, a bitmask of postprocessing steps that are
enabled, and an indicator of the current step. The bio completion
routine, if there was no I/O error, enqueues the first postprocessing
step. When that completes, it continues to the next step. Pages that
fail any postprocessing step have PageError set. Once all steps have
completed, pages without PageError set are set Uptodate, and all pages
are unlocked.
Also replace f2fs_encrypted_file() with a new function
f2fs_post_read_required() in places like direct I/O and garbage
collection that really should be testing whether the file needs special
I/O processing, not whether it is encrypted specifically.
This may also be useful for other future f2fs features such as
compression.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Currently, fscrypt provides fscrypt_decrypt_bio_pages() which decrypts a
bio's pages asynchronously, then unlocks them afterwards. But, this
assumes that decryption is the last "postprocessing step" for the bio,
so it's incompatible with additional postprocessing steps such as
authenticity verification after decryption.
Therefore, rename the existing fscrypt_decrypt_bio_pages() to
fscrypt_enqueue_decrypt_bio(). Then, add fscrypt_decrypt_bio() which
decrypts the pages in the bio synchronously without unlocking the pages,
nor setting them Uptodate; and add fscrypt_enqueue_decrypt_work(), which
enqueues work on the fscrypt_read_workqueue. The new functions will be
used by filesystems that support both fscrypt and fs-verity.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This fixes xfstests/generic/392.
The failure was caused by different times between 1) one marked in the last
fsync(2) call and 2) the other given by roll-forward recovery after power-cut.
The reason was that we skipped updating inode block at 1), since its i_size
was recoverable along with 4KB-aligned data writes, which was fixed by:
"f2fs: fix a wrong condition in f2fs_skip_inode_update"
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In make_dentry_ptr_block, it is confused with "&" for t->dentry_bitmap
but without "&" for t->dentry, so delete "&" to make code more readable.
Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If write is failed, we must deallocate the blocks that we couldn't write.
Cc: stable@vger.kernel.org
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Fix commit 97dd26ad8347 (f2fs: fix wrong AUTO_RECOVER condition).
We should use ~PAGE_MASK to determine whether i_size is aligned to
the f2fs's block size or not.
Signed-off-by: Junling Zheng <zhengjunling@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Reserve an F2FS feature flag and inode flag for fs-verity. This is an
in-development feature that is planned be discussed at LSF/MM 2018 [1].
It will provide file-based integrity and authenticity for read-only
files. Most code will be in a filesystem-independent module, with
smaller changes needed to individual filesystems that opt-in to
supporting the feature. An early prototype supporting F2FS is available
[2]. Reserving the F2FS on-disk bits for fs-verity will prevent users
of the prototype from conflicting with other new F2FS features.
Note that we're reserving the inode flag in f2fs_inode.i_advise, which
isn't really appropriate since it's not a hint or advice. But
->i_advise is already being used to hold the 'encrypt' flag; and F2FS's
->i_flags uses the generic FS_* values, so it seems ->i_flags can't be
used for an F2FS-specific flag without additional work to remove the
assumption that ->i_flags uses the generic flags namespace.
[1] https://marc.info/?l=linux-fsdevel&m=151690752225644
[2] https://git.kernel.org/pub/scm/linux/kernel/git/mhalcrow/linux.git/log/?h=fs-verity-dev
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch add a segment type check in IPU, in
case of something wrong with blkadd in dnode.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Since f2fs_inode_info is allocated with flag GFP_F2FS_ZERO, so we do not
need to initialize zero value for its member any more.
Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Nat entry set is used only in checkpoint(), and during checkpoint() we
won't flush new nat entry with unallocated address, so we don't need to
add new nat entry into nat set, then nat_entry_set::entry_cnt can
indicate actual entry count we need to flush in checkpoint().
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch check blkaddr more accuratly before issue a
write or read bio.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a new mount option `test_dummy_encryption'
to allow fscrypt to create a fake fscrypt context. This is used
by xfstests.
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a new feature, F2FS_FEATURE_LOST_FOUND, which
is set by mkfs. mkfs creates a directory named lost+found, which saves
unreachable files. If fsck finds a file which has no parent, or its
parent is removed by fsck, the file will be placed under lost+found
directory by fsck.
lost+found directory could not be encrypted. As a result, the root
directory cannot be encrypted too. So if LOST_FOUND feature is enabled,
let's avoid to encrypt root directory.
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Currently, we will leave the kernel with locks still held when the gc_range
is invalid. This patch fixes the bug.
Signed-off-by: Qiuyang Sun <sunqiuyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
For example, in arm64, free_nid_bitmap should be aligned to word size in order
to use bit operations.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When setting COLD_BIT_SHIFT flag in node block, we only need to call
set_cold_node() in new_node_page() and recover_inode_page() during
node page initialization. So remove unneeded set_cold_node() in other
places.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds nowait aio support[1].
Return EAGAIN if any of the following checks fail for direct I/O:
- i_rwsem is not lockable
- Blocks are not allocated at the write location
And xfstests generic/471 is passed.
[1]: 6be96d "Introduce RWF_NOWAIT and FMODE_AIO_NOWAIT"
Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch merges miscellaneous mount options into struct f2fs_mount_info,
After this patch, once we add new mount option, we don't need to worry
about recovery of it in remount_fs(), since we will recover the
f2fs_sb_info.mount_opt including all options.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Currently, we enable node SSR by default, and mixed
different types of node segment to do SSR more intensively.
Although reuse warm node is not allowed, warm node chain
will be destroyed by errors introduced by other types
node chain. So we'd better forbid reusing all types
of node to keep warm node chain.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Commit "0a007b97aad6"(f2fs: recover directory operations by fsync)
fixed xfstest generic/342 case, but it also increased the written
data and caused the performance degradation. In most cases, there's
no need to do so heavy fsync actually.
So we introduce new mount option "fsync_mode={posix,strict}" to
control the policy of fsync. "fsync_mode=posix" is set by default,
and means that f2fs uses a light fsync, which follows POSIX semantics.
And "fsync_mode=strict" means that it's a heavy fsync, which behaves
in line with xfs, ext4 and btrfs, where generic/342 will pass, but
the performance will regress.
Signed-off-by: Junling Zheng <zhengjunling@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
