When we try to use file already used as a quota file again (for the same
or different quota type), strange things can happen. At the very least
lockdep annotations may be wrong but also inode flags may be wrongly set
/ reset. When the file is used for two quota types at once we can even
corrupt the file and likely crash the kernel. Catch all these cases by
checking whether passed file is already used as quota file and bail
early in that case.
This fixes occasional generic/219 failure due to lockdep complaint.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reported-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201015110330.28716-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
left shifting m_lblk by blkbits was causing value overflow and hence
it was not able to convert unwritten to written extent.
So, make sure we typecast it to loff_t before do left shift operation.
Also in func ext4_convert_unwritten_io_end_vec(), make sure to initialize
ret variable to avoid accidentally returning an uninitialized ret.
This patch fixes the issue reported in ext4 for bs < ps with
dioread_nolock mount option.
Fixes: c8cc88163f ("ext4: Add support for blocksize < pagesize in dioread_nolock")
Cc: stable@kernel.org
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/af902b5db99e8b73980c795d84ad7bb417487e76.1602168865.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This implements journal callbacks j_submit|finish_inode_data_buffers()
with different behavior for data=journal: to write-protect pages under
commit, preventing changes to buffers writeably mapped to userspace.
If a buffer's content changes between commit's checksum calculation
and write-out to disk, it can cause journal recovery/mount failures
upon a kernel crash or power loss.
[ 27.334874] EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!
[ 27.339492] JBD2: Invalid checksum recovering data block 8705 in log
[ 27.342716] JBD2: recovery failed
[ 27.343316] EXT4-fs (loop0): error loading journal
mount: /ext4: can't read superblock on /dev/loop0.
In j_submit_inode_data_buffers() we write-protect the inode's pages
with write_cache_pages() and redirty w/ writepage callback if needed.
In j_finish_inode_data_buffers() there is nothing do to.
And in order to use the callbacks, inodes are added to the inode list
in transaction in __ext4_journalled_writepage() and ext4_page_mkwrite().
In ext4_page_mkwrite() we must make sure that the buffers are attached
to the transaction as jbddirty with write_end_fn(), as already done in
__ext4_journalled_writepage().
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Reported-by: Dann Frazier <dann.frazier@canonical.com>
Reported-by: kernel test robot <lkp@intel.com> # wbc.nr_to_write
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201006004841.600488-5-mfo@canonical.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
These are two fixes for data journalling required by
the next patch, discovered while testing it.
First, the optimization to return early if all buffers
are mapped is not appropriate for the next patch:
The inode _must_ be added to the transaction's list in
data=journal mode (so to write-protect pages on commit)
thus we cannot return early there.
Second, once that optimization to reduce transactions
was disabled for data=journal mode, more transactions
happened, and occasionally hit this warning message:
'JBD2: Spotted dirty metadata buffer'.
Reason is, block_page_mkwrite() will set_buffer_dirty()
before do_journal_get_write_access() that is there to
prevent it. This issue was masked by the optimization.
So, on data=journal use __block_write_begin() instead.
This also requires page locking and len recalculation.
(see block_page_mkwrite() for implementation details.)
Finally, as Jan noted there is little sharing between
data=journal and other modes in ext4_page_mkwrite().
However, a prototype of ext4_journalled_page_mkwrite()
showed there still would be lots of duplicated lines
(tens of) that didn't seem worth it.
Thus this patch ends up with an ugly goto to skip all
non-data journalling code (to avoid long indentations,
but that can be changed..) in the beginning, and just
a conditional in the transaction section.
Well, we skip a common part to data journalling which
is the page truncated check, but we do it again after
ext4_journal_start() when we re-acquire the page lock
(so not to acquire the page lock twice needlessly for
data journalling.)
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201006004841.600488-4-mfo@canonical.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Introduce journal callbacks to allow different behaviors
for an inode in journal_submit|finish_inode_data_buffers().
The existing users of the current behavior (ext4, ocfs2)
are adapted to use the previously exported functions
that implement the current behavior.
Users are callers of jbd2_journal_inode_ranged_write|wait(),
which adds the inode to the transaction's inode list with
the JI_WRITE|WAIT_DATA flags. Only ext4 and ocfs2 in-tree.
Both CONFIG_EXT4_FS and CONFIG_OCSFS2_FS select CONFIG_JBD2,
which builds fs/jbd2/commit.c and journal.c that define and
export the functions, so we can call directly in ext4/ocfs2.
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201006004841.600488-3-mfo@canonical.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now we only use sb_bread_unmovable() to read superblock and descriptor
block at mount time, so there is no opportunity that we need to clear
buffer verified bit and also handle buffer write_io error bit. But for
the sake of unification, let's introduce ext4_sb_bread_unmovable() to
replace all sb_bread_unmovable(). After this patch, we stop using read
helpers in fs/buffer.c.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20200924073337.861472-8-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If we readahead inode tables in __ext4_get_inode_loc(), it may bypass
buffer_write_io_error() check, so introduce ext4_sb_breadahead_unmovable()
to handle this special case.
This patch also replace sb_breadahead_unmovable() in ext4_fill_super()
for the sake of unification.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20200924073337.861472-6-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The previous patch add clear_buffer_verified() before we read metadata
block from disk again, but it's rather easy to miss clearing of this bit
because currently we read metadata buffer through different open codes
(e.g. ll_rw_block(), bh_submit_read() and invoke submit_bh() directly).
So, it's time to add common helpers to unify in all the places reading
metadata buffers instead. This patch add 3 helpers:
- ext4_read_bh_nowait(): async read metadata buffer if it's actually
not uptodate, clear buffer_verified bit before read from disk.
- ext4_read_bh(): sync version of read metadata buffer, it will wait
until the read operation return and check the return status.
- ext4_read_bh_lock(): try to lock the buffer before read buffer, it
will skip reading if the buffer is already locked.
After this patch, we need to use these helpers in all the places reading
metadata buffer instead of different open codes.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200924073337.861472-3-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The metadata buffer is no longer trusted after we read it from disk
again because it is not uptodate for some reasons (e.g. failed to write
back). Otherwise we may get below memory corruption problem in
ext4_ext_split()->memset() if we read stale data from the newly
allocated extent block on disk which has been failed to async write
out but miss verify again since the verified bit has already been set
on the buffer.
[ 29.774674] BUG: unable to handle kernel paging request at ffff88841949d000
...
[ 29.783317] Oops: 0002 [#2] SMP
[ 29.784219] R10: 00000000000f4240 R11: 0000000000002e28 R12: ffff88842fa1c800
[ 29.784627] CPU: 1 PID: 126 Comm: kworker/u4:3 Tainted: G D W
[ 29.785546] R13: ffffffff9cddcc20 R14: ffffffff9cddd420 R15: ffff88842fa1c2f8
[ 29.786679] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),BIOS ?-20190727_0738364
[ 29.787588] FS: 0000000000000000(0000) GS:ffff88842fa00000(0000) knlGS:0000000000000000
[ 29.789288] Workqueue: writeback wb_workfn
[ 29.790319] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 29.790321] (flush-8:0)
[ 29.790844] CR2: 0000000000000008 CR3: 00000004234f2000 CR4: 00000000000006f0
[ 29.791924] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 29.792839] RIP: 0010:__memset+0x24/0x30
[ 29.793739] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 29.794256] Code: 90 90 90 90 90 90 0f 1f 44 00 00 49 89 f9 48 89 d1 83 e2 07 48 c1 e9 033
[ 29.795161] Kernel panic - not syncing: Fatal exception in interrupt
...
[ 29.808149] Call Trace:
[ 29.808475] ext4_ext_insert_extent+0x102e/0x1be0
[ 29.809085] ext4_ext_map_blocks+0xa89/0x1bb0
[ 29.809652] ext4_map_blocks+0x290/0x8a0
[ 29.809085] ext4_ext_map_blocks+0xa89/0x1bb0
[ 29.809652] ext4_map_blocks+0x290/0x8a0
[ 29.810161] ext4_writepages+0xc85/0x17c0
...
Fix this by clearing buffer's verified bit if we read meta block from
disk again.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200924073337.861472-2-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If userspace asked fsmap to try to count the number of entries, we cannot
return more than UINT_MAX entries because fmh_entries is u32.
Therefore, stop counting if we hit this limit or else we will waste time
to return truncated results.
Fixes: 0c9ec4beec ("ext4: support GETFSMAP ioctls")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20201001222148.GA49520@magnolia
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Consider a situation when a filesystem was uncleanly shutdown and the
orphan list is not empty and a read-only mount is attempted. The orphan
list cleanup during mount will fail with:
ext4_check_bdev_write_error:193: comm mount: Error while async write back metadata
This happens because sbi->s_bdev_wb_err is not initialized when mounting
the filesystem in read only mode and so ext4_check_bdev_write_error()
falsely triggers.
Initialize sbi->s_bdev_wb_err unconditionally to avoid this problem.
Fixes: bc71726c72 ("ext4: abort the filesystem if failed to async write metadata buffer")
Cc: stable@kernel.org
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200928020556.710971-1-zhangxiaoxu5@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In case if the file already has underlying blocks/extents allocated
then we don't need to start a journal txn and can directly return
the underlying mapping. Currently ext4_iomap_begin() is used by
both DAX & DIO path. We can check if the write request is an
overwrite & then directly return the mapping information.
This could give a significant perf boost for multi-threaded writes
specially random overwrites.
On PPC64 VM with simulated pmem(DAX) device, ~10x perf improvement
could be seen in random writes (overwrite). Also bcoz this optimizes
away the spinlock contention during jbd2 slab cache allocation
(jbd2_journal_handle). On x86 VM, ~2x perf improvement was observed.
Reported-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/88e795d8a4d5cd22165c7ebe857ba91d68d8813e.1600401668.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The race condition could cause the persisted superblock checksum
to not match the contents of the superblock, causing the
superblock to be considered corrupt.
An example of the race follows. A first thread is interrupted in the
middle of a checksum calculation. Then, another thread changes the
superblock, calculates a new checksum, and sets it. Then, the first
thread resumes and sets the checksum based on the older superblock.
To fix, serialize the superblock checksum calculation using the buffer
header lock. While a spinlock is sufficient, the buffer header is
already there and there is precedent for locking it (e.g. in
ext4_commit_super).
Tested the patch by booting up a kernel with the patch, creating
a filesystem and some files (including some orphans), and then
unmounting and remounting the file system.
Cc: stable@kernel.org
Signed-off-by: Constantine Sapuntzakis <costa@purestorage.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200914161014.22275-1-costa@purestorage.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_mb_discard_group_preallocations() can be releasing group lock with
preallocations accumulated on its local list. Thus although
discard_pa_seq was incremented and concurrent allocating processes will
be retrying allocations, it can happen that premature ENOSPC error is
returned because blocks used for preallocations are not available for
reuse yet. Make sure we always free locally accumulated preallocations
before releasing group lock.
Fixes: 07b5b8e1ac ("ext4: mballoc: introduce pcpu seqcnt for freeing PA to improve ENOSPC handling")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200924150959.4335-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
As we test disk offline/online with running fsstress, we find fsstress
process is keeping running state.
kworker/u32:3-262 [004] ...1 140.787471: ext4_mb_discard_preallocations: dev 8,32 needed 114
....
kworker/u32:3-262 [004] ...1 140.787471: ext4_mb_discard_preallocations: dev 8,32 needed 114
ext4_mb_new_blocks
repeat:
ext4_mb_discard_preallocations_should_retry(sb, ac, &seq)
freed = ext4_mb_discard_preallocations
ext4_mb_discard_group_preallocations
this_cpu_inc(discard_pa_seq);
---> freed == 0
seq_retry = ext4_get_discard_pa_seq_sum
for_each_possible_cpu(__cpu)
__seq += per_cpu(discard_pa_seq, __cpu);
if (seq_retry != *seq) {
*seq = seq_retry;
ret = true;
}
As we see seq_retry is sum of discard_pa_seq every cpu, if
ext4_mb_discard_group_preallocations return zero discard_pa_seq in this
cpu maybe increase one, so condition "seq_retry != *seq" have always
been met.
Ritesh Harjani suggest to in ext4_mb_discard_group_preallocations function we
only increase discard_pa_seq when there is some PA to free.
Fixes: 07b5b8e1ac ("ext4: mballoc: introduce pcpu seqcnt for freeing PA to improve ENOSPC handling")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200916113859.1556397-3-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After moving ext4's bmap to iomap interface, swapon functionality
on files created using fallocate (which creates unwritten extents) are
failing. This is since iomap_bmap interface returns 0 for unwritten
extents and thus generic_swapfile_activate considers this as holes
and hence bail out with below kernel msg :-
[340.915835] swapon: swapfile has holes
To fix this we need to implement ->swap_activate aops in ext4
which will use ext4_iomap_report_ops. Since we only need to return
the list of extents so ext4_iomap_report_ops should be enough.
Cc: stable@kernel.org
Reported-by: Yuxuan Shui <yshuiv7@gmail.com>
Fixes: ac58e4fb03 ("ext4: move ext4 bmap to use iomap infrastructure")
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200904091653.1014334-1-riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fscrypt_set_test_dummy_encryption() requires that the optional argument
to the test_dummy_encryption mount option be specified as a substring_t.
That doesn't work well with filesystems that use the new mount API,
since the new way of parsing mount options doesn't use substring_t.
Make it take the argument as a 'const char *' instead.
Instead of moving the match_strdup() into the callers in ext4 and f2fs,
make them just use arg->from directly. Since the pattern is
"test_dummy_encryption=%s", the argument will be null-terminated.
Acked-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20200917041136.178600-14-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
The behavior of the test_dummy_encryption mount option is that when a
new file (or directory or symlink) is created in an unencrypted
directory, it's automatically encrypted using a dummy encryption policy.
That's it; in particular, the encryption (or lack thereof) of existing
files (or directories or symlinks) doesn't change.
Unfortunately the implementation of test_dummy_encryption is a bit weird
and confusing. When test_dummy_encryption is enabled and a file is
being created in an unencrypted directory, we set up an encryption key
(->i_crypt_info) for the directory. This isn't actually used to do any
encryption, however, since the directory is still unencrypted! Instead,
->i_crypt_info is only used for inheriting the encryption policy.
One consequence of this is that the filesystem ends up providing a
"dummy context" (policy + nonce) instead of a "dummy policy". In
commit ed318a6cc0 ("fscrypt: support test_dummy_encryption=v2"), I
mistakenly thought this was required. However, actually the nonce only
ends up being used to derive a key that is never used.
Another consequence of this implementation is that it allows for
'inode->i_crypt_info != NULL && !IS_ENCRYPTED(inode)', which is an edge
case that can be forgotten about. For example, currently
FS_IOC_GET_ENCRYPTION_POLICY on an unencrypted directory may return the
dummy encryption policy when the filesystem is mounted with
test_dummy_encryption. That seems like the wrong thing to do, since
again, the directory itself is not actually encrypted.
Therefore, switch to a more logical and maintainable implementation
where the dummy encryption policy inheritance is done without setting up
keys for unencrypted directories. This involves:
- Adding a function fscrypt_policy_to_inherit() which returns the
encryption policy to inherit from a directory. This can be a real
policy, a dummy policy, or no policy.
- Replacing struct fscrypt_dummy_context, ->get_dummy_context(), etc.
with struct fscrypt_dummy_policy, ->get_dummy_policy(), etc.
- Making fscrypt_fname_encrypted_size() take an fscrypt_policy instead
of an inode.
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Acked-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20200917041136.178600-13-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Convert ext4 to use the new functions fscrypt_prepare_new_inode() and
fscrypt_set_context(). This avoids calling
fscrypt_get_encryption_info() from within a transaction, which can
deadlock because fscrypt_get_encryption_info() isn't GFP_NOFS-safe.
For more details about this problem, see the earlier patch
"fscrypt: add fscrypt_prepare_new_inode() and fscrypt_set_context()".
Link: https://lore.kernel.org/r/20200917041136.178600-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
To compute a new inode's xattr credits, we need to know whether the
inode will be encrypted or not. When we switch to use the new helper
function fscrypt_prepare_new_inode(), we won't find out whether the
inode will be encrypted until slightly later than is currently the case.
That will require moving the code block that computes the xattr credits.
To make this easier and reduce the length of __ext4_new_inode(), move
this code block into a new function ext4_xattr_credits_for_new_inode().
Link: https://lore.kernel.org/r/20200917041136.178600-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Pull writeback fixes from Jan Kara:
"Fixes for writeback code occasionally skipping writeback of some
inodes or livelocking sync(2)"
* tag 'writeback_for_v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
writeback: Drop I_DIRTY_TIME_EXPIRE
writeback: Fix sync livelock due to b_dirty_time processing
writeback: Avoid skipping inode writeback
writeback: Protect inode->i_io_list with inode->i_lock
Pull ext4 updates from Ted Ts'o:
"Improvements to ext4's block allocator performance for very large file
systems, especially when the file system or files which are highly
fragmented. There is a new mount option, prefetch_block_bitmaps which
will pull in the block bitmaps and set up the in-memory buddy bitmaps
when the file system is initially mounted.
Beyond that, a lot of bug fixes and cleanups. In particular, a number
of changes to make ext4 more robust in the face of write errors or
file system corruptions"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (46 commits)
ext4: limit the length of per-inode prealloc list
ext4: reorganize if statement of ext4_mb_release_context()
ext4: add mb_debug logging when there are lost chunks
ext4: Fix comment typo "the the".
jbd2: clean up checksum verification in do_one_pass()
ext4: change to use fallthrough macro
ext4: remove unused parameter of ext4_generic_delete_entry function
mballoc: replace seq_printf with seq_puts
ext4: optimize the implementation of ext4_mb_good_group()
ext4: delete invalid comments near ext4_mb_check_limits()
ext4: fix typos in ext4_mb_regular_allocator() comment
ext4: fix checking of directory entry validity for inline directories
fs: prevent BUG_ON in submit_bh_wbc()
ext4: correctly restore system zone info when remount fails
ext4: handle add_system_zone() failure in ext4_setup_system_zone()
ext4: fold ext4_data_block_valid_rcu() into the caller
ext4: check journal inode extents more carefully
ext4: don't allow overlapping system zones
ext4: handle error of ext4_setup_system_zone() on remount
ext4: delete the invalid BUGON in ext4_mb_load_buddy_gfp()
...
In the scenario of writing sparse files, the per-inode prealloc list may
be very long, resulting in high overhead for ext4_mb_use_preallocated().
To circumvent this problem, we limit the maximum length of per-inode
prealloc list to 512 and allow users to modify it.
After patching, we observed that the sys ratio of cpu has dropped, and
the system throughput has increased significantly. We created a process
to write the sparse file, and the running time of the process on the
fixed kernel was significantly reduced, as follows:
Running time on unfixed kernel：
[root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat
real 0m2.051s
user 0m0.008s
sys 0m2.026s
Running time on fixed kernel：
[root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat
real 0m0.471s
user 0m0.004s
sys 0m0.395s
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Link: https://lore.kernel.org/r/d7a98178-056b-6db5-6bce-4ead23f4a257@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
It might be better to adjust the code in two places:
1. Determine whether grp is currupt or not should be placed first.
2. (cr<=2 && free <ac->ac_g_ex.fe_len)should may belong to the crx
strategy, and it may be more appropriate to put it in the
subsequent switch statement block. For cr1, cr2, the conditions
in switch potentially realize the above judgment. For cr0, we
should add (free <ac->ac_g_ex.fe_len) judgment, and then delete
(free / fragments) >= ac->ac_g_ex.fe_len), because cr0 returns
true by default.
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/e20b2d8f-1154-adb7-3831-a9e11ba842e9@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
