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>
Rename system_blks to s_system_blks inside ext4_sb_info, keep
the naming rules consistent with other variables, which is
convenient for code reading and writing.
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/1600916623-544-2-git-send-email-brookxu@tencent.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Rename journal_dev to s_journal_dev inside ext4_sb_info, keep
the naming rules consistent with other variables, which is
convenient for code reading and writing.
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/1600916623-544-1-git-send-email-brookxu@tencent.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>
When ext4_journal_get_write_access() fails, we should
terminate the execution flow and release n_group_desc,
iloc.bh, dind and gdb_bh.
Cc: stable@kernel.org
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20200829025403.3139-1-dinghao.liu@zju.edu.cn
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The 'handle' argument is not used for anything so simply remove it.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200826133116.11592-1-nborisov@suse.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Fields s_free_blocks_count_hi, s_r_blocks_count_hi and s_blocks_count_hi
are not valid if EXT4_FEATURE_INCOMPAT_64BIT is not enabled and should be
treated as zeroes.
Signed-off-by: Petr Malat <oss@malat.biz>
Link: https://lore.kernel.org/r/20200825150016.3363-1-oss@malat.biz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Delete repeated words in fs/ext4/.
{the, this, of, we, after}
Also change spelling of "xttr" in inline.c to "xattr" in 2 places.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200805024850.12129-1-rdunlap@infradead.org
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>
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Merge tag 'writeback_for_v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
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
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.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
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>
Reorganize the if statement of ext4_mb_release_context(), make it
easier to read.
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Link: https://lore.kernel.org/r/5439ac6f-db79-ad68-76c1-a4dda9aa0cc3@gmail.com
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Lost chunks are when some other process raced with the current thread
to grab a particular block allocation. Add mb_debug log for
developers who wants to see how often this is happening for a
particular workload.
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Link: https://lore.kernel.org/r/0a165ac0-1912-aebd-8a0d-b42e7cd1aea1@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The ext4_generic_delete_entry function does not use the parameter
handle, so it can be removed.
Signed-off-by: Kyoungho Koo <rnrudgh@gmail.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200810080701.GA14160@koo-Z370-HD3
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
seq_puts is a lot cheaper than seq_printf, so use that to print
literal strings.
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200810022158.9167-1-vulab@iscas.ac.cn
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>
These comments do not seem to be related to ext4_mb_check_limits(),
it may be invalid.
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/c49faf0c-d5d5-9c51-6911-9e0ff57c6bfa@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_search_dir() and ext4_generic_delete_entry() can be called both for
standard director blocks and for inline directories stored inside inode
or inline xattr space. For the second case we didn't call
ext4_check_dir_entry() with proper constraints that could result in
accepting corrupted directory entry as well as false positive filesystem
errors like:
EXT4-fs error (device dm-0): ext4_search_dir:1395: inode #28320400:
block 113246792: comm dockerd: bad entry in directory: directory entry too
close to block end - offset=0, inode=28320403, rec_len=32, name_len=8,
size=4096
Fix the arguments passed to ext4_check_dir_entry().
Fixes: 109ba779d6 ("ext4: check for directory entries too close to block end")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200731162135.8080-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If a device is hot-removed --- for example, when a physical device is
unplugged from pcie slot or a nbd device's network is shutdown ---
this can result in a BUG_ON() crash in submit_bh_wbc(). This is
because the when the block device dies, the buffer heads will have
their Buffer_Mapped flag get cleared, leading to the crash in
submit_bh_wbc.
We had attempted to work around this problem in commit a17712c8
("ext4: check superblock mapped prior to committing"). Unfortunately,
it's still possible to hit the BUG_ON(!buffer_mapped(bh)) if the
device dies between when the work-around check in ext4_commit_super()
and when submit_bh_wbh() is finally called:
Code path:
ext4_commit_super
judge if 'buffer_mapped(sbh)' is false, return <== commit a17712c8
lock_buffer(sbh)
...
unlock_buffer(sbh)
__sync_dirty_buffer(sbh,...
lock_buffer(sbh)
judge if 'buffer_mapped(sbh))' is false, return <== added by this patch
submit_bh(...,sbh)
submit_bh_wbc(...,sbh,...)
[100722.966497] kernel BUG at fs/buffer.c:3095! <== BUG_ON(!buffer_mapped(bh))' in submit_bh_wbc()
[100722.966503] invalid opcode: 0000 [#1] SMP
[100722.966566] task: ffff8817e15a9e40 task.stack: ffffc90024744000
[100722.966574] RIP: 0010:submit_bh_wbc+0x180/0x190
[100722.966575] RSP: 0018:ffffc90024747a90 EFLAGS: 00010246
[100722.966576] RAX: 0000000000620005 RBX: ffff8818a80603a8 RCX: 0000000000000000
[100722.966576] RDX: ffff8818a80603a8 RSI: 0000000000020800 RDI: 0000000000000001
[100722.966577] RBP: ffffc90024747ac0 R08: 0000000000000000 R09: ffff88207f94170d
[100722.966578] R10: 00000000000437c8 R11: 0000000000000001 R12: 0000000000020800
[100722.966578] R13: 0000000000000001 R14: 000000000bf9a438 R15: ffff88195f333000
[100722.966580] FS: 00007fa2eee27700(0000) GS:ffff88203d840000(0000) knlGS:0000000000000000
[100722.966580] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[100722.966581] CR2: 0000000000f0b008 CR3: 000000201a622003 CR4: 00000000007606e0
[100722.966582] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[100722.966583] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[100722.966583] PKRU: 55555554
[100722.966583] Call Trace:
[100722.966588] __sync_dirty_buffer+0x6e/0xd0
[100722.966614] ext4_commit_super+0x1d8/0x290 [ext4]
[100722.966626] __ext4_std_error+0x78/0x100 [ext4]
[100722.966635] ? __ext4_journal_get_write_access+0xca/0x120 [ext4]
[100722.966646] ext4_reserve_inode_write+0x58/0xb0 [ext4]
[100722.966655] ? ext4_dirty_inode+0x48/0x70 [ext4]
[100722.966663] ext4_mark_inode_dirty+0x53/0x1e0 [ext4]
[100722.966671] ? __ext4_journal_start_sb+0x6d/0xf0 [ext4]
[100722.966679] ext4_dirty_inode+0x48/0x70 [ext4]
[100722.966682] __mark_inode_dirty+0x17f/0x350
[100722.966686] generic_update_time+0x87/0xd0
[100722.966687] touch_atime+0xa9/0xd0
[100722.966690] generic_file_read_iter+0xa09/0xcd0
[100722.966694] ? page_cache_tree_insert+0xb0/0xb0
[100722.966704] ext4_file_read_iter+0x4a/0x100 [ext4]
[100722.966707] ? __inode_security_revalidate+0x4f/0x60
[100722.966709] __vfs_read+0xec/0x160
[100722.966711] vfs_read+0x8c/0x130
[100722.966712] SyS_pread64+0x87/0xb0
[100722.966716] do_syscall_64+0x67/0x1b0
[100722.966719] entry_SYSCALL64_slow_path+0x25/0x25
To address this, add the check of 'buffer_mapped(bh)' to
__sync_dirty_buffer(). This also has the benefit of fixing this for
other file systems.
With this addition, we can drop the workaround in ext4_commit_supper().
[ Commit description rewritten by tytso. ]
Signed-off-by: Xianting Tian <xianting_tian@126.com>
Link: https://lore.kernel.org/r/1596211825-8750-1-git-send-email-xianting_tian@126.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When remounting filesystem fails late during remount handling and
block_validity mount option is also changed during the remount, we fail
to restore system zone information to a state matching the mount option.
This is mostly harmless, just the block validity checking will not match
the situation described by the mount option. Make sure these two are always
consistent.
Reported-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200728130437.7804-7-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There's one place that fails to handle error from add_system_zone() call
and thus we can fail to protect superblock and group-descriptor blocks
properly in case of ENOMEM. Fix it.
Reported-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200728130437.7804-6-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After the previous patch, ext4_data_block_valid_rcu() has a single
caller. Fold it into it.
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200728130437.7804-5-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently, system zones just track ranges of block, that are "important"
fs metadata (bitmaps, group descriptors, journal blocks, etc.). This
however complicates how extent tree (or indirect blocks) can be checked
for inodes that actually track such metadata - currently the journal
inode but arguably we should be treating quota files or resize inode
similarly. We cannot run __ext4_ext_check() on such metadata inodes when
loading their extents as that would immediately trigger the validity
checks and so we just hack around that and special-case the journal
inode. This however leads to a situation that a journal inode which has
extent tree of depth at least one can have invalid extent tree that gets
unnoticed until ext4_cache_extents() crashes.
To overcome this limitation, track inode number each system zone belongs
to (0 is used for zones not belonging to any inode). We can then verify
inode number matches the expected one when verifying extent tree and
thus avoid the false errors. With this there's no need to to
special-case journal inode during extent tree checking anymore so remove
it.
Fixes: 0a944e8a6c ("ext4: don't perform block validity checks on the journal inode")
Reported-by: Wolfgang Frisch <wolfgang.frisch@suse.com>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200728130437.7804-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently, add_system_zone() just silently merges two added system zones
that overlap. However the overlap should not happen and it generally
suggests that some unrelated metadata overlap which indicates the fs is
corrupted. We should have caught such problems earlier (e.g. in
ext4_check_descriptors()) but add this check as another line of defense.
In later patch we also use this for stricter checking of journal inode
extent tree.
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200728130437.7804-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_setup_system_zone() can fail. Handle the failure in ext4_remount().
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200728130437.7804-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This numbers can be analized by system automation similar to errors_count.
In ideal world it would be nice to have separate counters for different
log-levels, but this makes this patch too intrusive.
Signed-off-by: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Link: https://lore.kernel.org/r/20200725123313.4467-1-dmtrmonakhov@yandex-team.ru
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently there is a problem with mount options that can be both set by
vfs using mount flags or by a string parsing in ext4.
i_version/iversion options gets lost after remount, for example
$ mount -o i_version /dev/pmem0 /mnt
$ grep pmem0 /proc/self/mountinfo | grep i_version
310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,seclabel,i_version
$ mount -o remount,ro /mnt
$ grep pmem0 /proc/self/mountinfo | grep i_version
nolazytime gets ignored by ext4 on remount, for example
$ mount -o lazytime /dev/pmem0 /mnt
$ grep pmem0 /proc/self/mountinfo | grep lazytime
310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,lazytime,seclabel
$ mount -o remount,nolazytime /mnt
$ grep pmem0 /proc/self/mountinfo | grep lazytime
310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,lazytime,seclabel
Fix it by applying the SB_LAZYTIME and SB_I_VERSION flags from *flags to
s_flags before we parse the option and use the resulting state of the
same flags in *flags at the end of successful remount.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200723150526.19931-1-lczerner@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
For file systems where we can afford to keep the buddy bitmaps cached,
we can speed up initial writes to large file systems by starting to
load the block allocation bitmaps as soon as the file system is
mounted. This won't work well for _super_ large file systems, or
memory constrained systems, so we only enable this when it is
requested via a mount option.
Addresses-Google-Bug: 159488342
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Modify the ext4_read_block_bitmap_load tracepoint so that it tells us
whether a block bitmap is being prefetched.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Artem Blagodarenko <artem.blagodarenko@gmail.com>
Parameter gfp_mask in jbd2_journal_try_to_free_buffers() is no longer
used after commit <536fc240e7147> ("jbd2: clean up
jbd2_journal_try_to_free_buffers()"), so just remove it.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20200620025427.1756360-6-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There is a risk of filesystem inconsistency if we failed to async write
back metadata buffer in the background. Because of current buffer's end
io procedure is handled by end_buffer_async_write() in the block layer,
and it only clear the buffer's uptodate flag and mark the write_io_error
flag, so ext4 cannot detect such failure immediately. In most cases of
getting metadata buffer (e.g. ext4_read_inode_bitmap()), although the
buffer's data is actually uptodate, it may still read data from disk
because the buffer's uptodate flag has been cleared. Finally, it may
lead to on-disk filesystem inconsistency if reading old data from the
disk successfully and write them out again.
This patch detect bdev mapping->wb_err when getting journal's write
access and mark the filesystem error if bdev's mapping->wb_err was
increased, this could prevent further writing and potential
inconsistency.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200620025427.1756360-2-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
