jbd2: increase the journal IO's priority

[ Upstream commit 6a3afb6ac6dfab158ebdd4b87941178f58c8939f ]

Current jbd2 only add REQ_SYNC for descriptor block, metadata log
buffer, commit buffer and sup

jbd2: increase the journal IO's priority

[ Upstream commit 6a3afb6ac6dfab158ebdd4b87941178f58c8939f ]

Current jbd2 only add REQ_SYNC for descriptor block, metadata log
buffer, commit buffer and superblock buffer, the submitted IO could be
throttled by writeback throttle in block layer, that could lead to
priority inversion in some cases. The log IO looks like a kind of high
priority metadata IO, so it should not be throttled by WBT like QOS
policies in block layer, let's add REQ_SYNC | REQ_IDLE to exempt from
writeback throttle, and also add REQ_META together indicates it's a
metadata IO.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20231129114740.2686201-2-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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jbd2: remove unused t_handle_lock

Since commit f7f497cb7024 ("jbd2: kill t_handle_lock
transaction spinlock"), this lock has been no use.

Fixes: f7f497cb7024 ("jbd2: kill t_handle_lock transaction

jbd2: remove unused t_handle_lock

Since commit f7f497cb7024 ("jbd2: kill t_handle_lock
transaction spinlock"), this lock has been no use.

Fixes: f7f497cb7024 ("jbd2: kill t_handle_lock transaction spinlock")
Signed-off-by: Wang Jianjian <wangjianjian0@foxmail.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/tencent_8477CBE568348A1862C64E393D587B342008@qq.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: fix a race when checking checkpoint buffer busy

Before removing checkpoint buffer from the t_checkpoint_list, we have to
check both BH_Dirty and BH_Lock bits together to distinguish buffers
ha

jbd2: fix a race when checking checkpoint buffer busy

Before removing checkpoint buffer from the t_checkpoint_list, we have to
check both BH_Dirty and BH_Lock bits together to distinguish buffers
have not been or were being written back. But __cp_buffer_busy() checks
them separately, it first check lock state and then check dirty, the
window between these two checks could be raced by writing back
procedure, which locks buffer and clears buffer dirty before I/O
completes. So it cannot guarantee checkpointing buffers been written
back to disk if some error happens later. Finally, it may clean
checkpoint transactions and lead to inconsistent filesystem.

jbd2_journal_forget() and __journal_try_to_free_buffer() also have the
same problem (journal_unmap_buffer() escape from this issue since it's
running under the buffer lock), so fix them through introducing a new
helper to try holding the buffer lock and remove really clean buffer.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217490
Cc: stable@vger.kernel.org
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-6-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: remove t_checkpoint_io_list

Since t_checkpoint_io_list was stop using in jbd2_log_do_checkpoint()
now, it's time to remove the whole t_checkpoint_io_list logic.

Signed-off-by: Zhang Yi <yi.zh

jbd2: remove t_checkpoint_io_list

Since t_checkpoint_io_list was stop using in jbd2_log_do_checkpoint()
now, it's time to remove the whole t_checkpoint_io_list logic.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-3-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: continue to record log between each mount

For a newly mounted file system, the journal committing thread always
record new transactions from the start of the journal area, no matter
whether th

jbd2: continue to record log between each mount

For a newly mounted file system, the journal committing thread always
record new transactions from the start of the journal area, no matter
whether the journal was clean or just has been recovered. So the logdump
code in debugfs cannot dump continuous logs between each mount, it is
disadvantageous to analysis corrupted file system image and locate the
file system inconsistency bugs.

If we get a corrupted file system in the running products and want to
find out what has happened, besides lookup the system log, one effective
way is to backtrack the journal log. But we may not always run e2fsck
before each mount and the default fsck -a mode also cannot always
checkout all inconsistencies, so it could left over some inconsistencies
into the next mount until we detect it. Finally, transactions in the
journal may probably discontinuous and some relatively new transactions
has been covered, it becomes hard to analyse. If we could record
transactions continuously between each mount, we could acquire more
useful info from the journal. Like this:

|Previous mount checkpointed/recovered logs|Current mount logs |
|{------}{---}{--------} ... {------}| ... |{======}{========}...000000|

And yes the journal area is limited and cannot record everything, the
problematic transaction may also be covered even if we do this, but
this is still useful for fuzzy tests and short-running products.

This patch save the head blocknr in the superblock after flushing the
journal or unmounting the file system, let the next mount could continue
to record new transaction behind it. This change is backward compatible
because the old kernel does not care about the head blocknr of the
journal. It is also fine if we mount a clean old image without valid
head blocknr, we fail back to set it to s_first just like before.
Finally, for the case of mount an unclean file system, we could also get
the journal head easily after scanning/replaying the journal, it will
continue to record new transaction after the recovered transactions.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230322013353.1843306-2-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: remove j_format_version

journal->j_format_version is no longer used, remove it.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by

jbd2: remove j_format_version

journal->j_format_version is no longer used, remove it.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230315013128.3911115-7-chengzhihao1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: switch to check format version in superblock directly

We should only check and set extented features if journal format version
is 2, and now we check the in memory copy of the superblock
'jour

jbd2: switch to check format version in superblock directly

We should only check and set extented features if journal format version
is 2, and now we check the in memory copy of the superblock
'journal->j_format_version', which relys on the parameter initialization
sequence, switch to use the h_blocktype in superblock cloud be more
clear.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230315013128.3911115-5-chengzhihao1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: remove unused feature macros

JBD2_HAS_[IN|RO_]COMPAT_FEATURE macros are no longer used, just remove
them.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhiha

jbd2: remove unused feature macros

JBD2_HAS_[IN|RO_]COMPAT_FEATURE macros are no longer used, just remove
them.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230315013128.3911115-4-chengzhihao1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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ext4, jbd2: add an optimized bmap for the journal inode

The generic bmap() function exported by the VFS takes locks and does
checks that are not necessary for the journal inode. So allow the
file s

ext4, jbd2: add an optimized bmap for the journal inode

The generic bmap() function exported by the VFS takes locks and does
checks that are not necessary for the journal inode. So allow the
file system to set a journal-optimized bmap function in
journal->j_bmap.

Reported-by: syzbot+9543479984ae9e576000@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=e4aaa78795e490421c79f76ec3679006c8ff4cf0
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2,ocfs2: move jbd2_journal_submit_inode_data_buffers to ocfs2

jbd2_journal_submit_inode_data_buffers is only used by ocfs2, so move it
there to prepare for removing generic_writepages.

Link: htt

jbd2,ocfs2: move jbd2_journal_submit_inode_data_buffers to ocfs2

jbd2_journal_submit_inode_data_buffers is only used by ocfs2, so move it
there to prepare for removing generic_writepages.

Link: https://lkml.kernel.org/r/20221229161031.391878-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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jbd2: switch jbd2_submit_inode_data() to use fs-provided hook for data writeout

jbd2_submit_inode_data() hardcoded use of
jbd2_journal_submit_inode_data_buffers() for submission of data pages.
Make

jbd2: switch jbd2_submit_inode_data() to use fs-provided hook for data writeout

jbd2_submit_inode_data() hardcoded use of
jbd2_journal_submit_inode_data_buffers() for submission of data pages.
Make it use j_submit_inode_data_buffers hook instead. This effectively
switches ext4 fastcommits to use ext4_writepages() for data writeout
instead of generic_writepages().

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221207112722.22220-9-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: unexport jbd2_log_start_commit()

jbd2_log_start_commit() is not used outside of jbd2 so unexport it. Also
make __jbd2_log_start_commit() static when we are at it.

Signed-off-by: Jan Kara <jac

jbd2: unexport jbd2_log_start_commit()

jbd2_log_start_commit() is not used outside of jbd2 so unexport it. Also
make __jbd2_log_start_commit() static when we are at it.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Link: https://lore.kernel.org/r/20220608112355.4397-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: remove unused exports for jbd2 debugging

Jbd2 exports jbd2_journal_enable_debug and __jbd2_debug() depite the
first is used only in fs/jbd2/journal.c and the second only within jbd2
code. Remo

jbd2: remove unused exports for jbd2 debugging

Jbd2 exports jbd2_journal_enable_debug and __jbd2_debug() depite the
first is used only in fs/jbd2/journal.c and the second only within jbd2
code. Remove the pointless exports make jbd2_journal_enable_debug
static.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Link: https://lore.kernel.org/r/20220608112355.4397-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: rename jbd_debug() to jbd2_debug()

The name of jbd_debug() is confusing as all functions inside jbd2 have
jbd2_ prefix. Rename jbd_debug() to jbd2_debug(). No functional changes.

Signed-off-b

jbd2: rename jbd_debug() to jbd2_debug()

The name of jbd_debug() is confusing as all functions inside jbd2 have
jbd2_ prefix. Rename jbd_debug() to jbd2_debug(). No functional changes.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Link: https://lore.kernel.org/r/20220608112355.4397-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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fs/jbd2: Fix the documentation of the jbd2_write_superblock() callers

Commit 2a222ca992c3 ("fs: have submit_bh users pass in op and flags
separately") renamed the jbd2_write_superblock() 'write_op'

fs/jbd2: Fix the documentation of the jbd2_write_superblock() callers

Commit 2a222ca992c3 ("fs: have submit_bh users pass in op and flags
separately") renamed the jbd2_write_superblock() 'write_op' argument into
'write_flags'. Propagate this change to the jbd2_write_superblock()
callers. Additionally, change the type of 'write_flags' into blk_opf_t.

Cc: Mike Christie <michael.christie@oracle.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-57-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio

Also convert it to return a bool since it's called from release_folio().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio

Also convert it to return a bool since it's called from release_folio().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

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ext4: Convert invalidatepage to invalidate_folio

Extensive changes, but fairly mechanical.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@open

ext4: Convert invalidatepage to invalidate_folio

Extensive changes, but fairly mechanical.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs

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jbd2: kill t_handle_lock transaction spinlock

This patch kills t_handle_lock transaction spinlock completely from
jbd2.

To explain the reasoning, currently there were three sites at which
this spin

jbd2: kill t_handle_lock transaction spinlock

This patch kills t_handle_lock transaction spinlock completely from
jbd2.

To explain the reasoning, currently there were three sites at which
this spinlock was used.

1. jbd2_journal_wait_updates()
a. Based on careful code review it can be seen that, we don't need this
lock here. This is since we wait for any currently ongoing updates
based on a atomic variable t_updates. And we anyway don't take any
t_handle_lock while in stop_this_handle().
i.e.

write_lock(&journal->j_state_lock()
jbd2_journal_wait_updates() stop_this_handle()
while (atomic_read(txn->t_updates) { |
DEFINE_WAIT(wait); |
prepare_to_wait(); |
if (atomic_read(txn->t_updates) if (atomic_dec_and_test(txn->t_updates))
write_unlock(&journal->j_state_lock);
schedule(); wake_up()
write_lock(&journal->j_state_lock);
finish_wait();
}
txn->t_state = T_COMMIT
write_unlock(&journal->j_state_lock);

b. Also note that between atomic_inc(&txn->t_updates) in
start_this_handle() and jbd2_journal_wait_updates(), the
synchronization happens via read_lock(journal->j_state_lock) in
start_this_handle();

2. jbd2_journal_extend()
a. jbd2_journal_extend() is called with the handle of each process from
task_struct. So no lock required in updating member fields of handle_t

b. For member fields of h_transaction, all updates happens only via
atomic APIs (which is also within read_lock()).
So, no need of this transaction spinlock.

3. update_t_max_wait()
Based on Jan suggestion, this can be carefully removed using atomic
cmpxchg API.
Note that there can be several processes which are waiting for a new
transaction to be allocated and started. For doing this only one
process will succeed in taking write_lock() and allocating a new txn.
After that all of the process will be updating the t_max_wait (max
transaction wait time). This can be done via below method w/o taking
any locks using atomic cmpxchg.
For more details refer [1]

new = get_new_val();
old = READ_ONCE(ptr->max_val);
while (old < new)
old = cmpxchg(&ptr->max_val, old, new);

[1]: https://lwn.net/Articles/849237/

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/d89e599658b4a1f3893a48c6feded200073037fc.1644992076.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: refactor wait logic for transaction updates into a common function

No functionality change as such in this patch. This only refactors the
common piece of code which waits for t_updates to fini

jbd2: refactor wait logic for transaction updates into a common function

No functionality change as such in this patch. This only refactors the
common piece of code which waits for t_updates to finish into a common
function named as jbd2_journal_wait_updates(journal_t *)

Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/8c564f70f4b2591171677a2a74fccb22a7b6c3a4.1642416995.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: cleanup unused functions declarations from jbd2.h

During code review found no references of few of these below function
declarations. This patch cleans those up from jbd2.h

Signed-off-by: Rit

jbd2: cleanup unused functions declarations from jbd2.h

During code review found no references of few of these below function
declarations. This patch cleans those up from jbd2.h

Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/30d1fc327becda197a4136cf9cdc73d9baa3b7b9.1642416995.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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ext4: fast commit may not fallback for ineligible commit

For the follow scenario:
1. jbd start commit transaction n
2. task A get new handle for transaction n+1
3. task A do some ineligible actions

ext4: fast commit may not fallback for ineligible commit

For the follow scenario:
1. jbd start commit transaction n
2. task A get new handle for transaction n+1
3. task A do some ineligible actions and mark FC_INELIGIBLE
4. jbd complete transaction n and clean FC_INELIGIBLE
5. task A call fsync

In this case fast commit will not fallback to full commit and
transaction n+1 also not handled by jbd.

Make ext4_fc_mark_ineligible() also record transaction tid for
latest ineligible case, when call ext4_fc_cleanup() check
current transaction tid, if small than latest ineligible tid
do not clear the EXT4_MF_FC_INELIGIBLE.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: Ritesh Harjani <riteshh@linux.ibm.com>
Suggested-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Signed-off-by: Xin Yin <yinxin.x@bytedance.com>
Link: https://lore.kernel.org/r/20220117093655.35160-2-yinxin.x@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

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ext4: fast commit may not fallback for ineligible commit

[ Upstream commit e85c81ba8859a4c839bcd69c5d83b32954133a5b ]

For the follow scenario:
1. jbd start commit transaction n
2. task A get new ha

ext4: fast commit may not fallback for ineligible commit

[ Upstream commit e85c81ba8859a4c839bcd69c5d83b32954133a5b ]

For the follow scenario:
1. jbd start commit transaction n
2. task A get new handle for transaction n+1
3. task A do some ineligible actions and mark FC_INELIGIBLE
4. jbd complete transaction n and clean FC_INELIGIBLE
5. task A call fsync

In this case fast commit will not fallback to full commit and
transaction n+1 also not handled by jbd.

Make ext4_fc_mark_ineligible() also record transaction tid for
latest ineligible case, when call ext4_fc_cleanup() check
current transaction tid, if small than latest ineligible tid
do not clear the EXT4_MF_FC_INELIGIBLE.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: Ritesh Harjani <riteshh@linux.ibm.com>
Suggested-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Signed-off-by: Xin Yin <yinxin.x@bytedance.com>
Link: https://lore.kernel.org/r/20220117093655.35160-2-yinxin.x@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

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ext4: inline jbd2_journal_[un]register_shrinker()

The function jbd2_journal_unregister_shrinker() was getting called
twice when the file system was getting unmounted. On Power and ARM
platforms thi

ext4: inline jbd2_journal_[un]register_shrinker()

The function jbd2_journal_unregister_shrinker() was getting called
twice when the file system was getting unmounted. On Power and ARM
platforms this was causing kernel crash when unmounting the file
system, when a percpu_counter was destroyed twice.

Fix this by removing jbd2_journal_[un]register_shrinker() functions,
and inlining the shrinker setup and teardown into
journal_init_common() and jbd2_journal_destroy(). This means that
ext4 and ocfs2 now no longer need to know about registering and
unregistering jbd2's shrinker.

Also, while we're at it, rename the percpu counter from
j_jh_shrink_count to j_checkpoint_jh_count, since this makes it
clearer what this counter is intended to track.

Link: https://lore.kernel.org/r/20210705145025.3363130-1-tytso@mit.edu
Fixes: 4ba3fcdde7e3 ("jbd2,ext4: add a shrinker to release checkpointed buffers")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2,ext4: add a shrinker to release checkpointed buffers

Current metadata buffer release logic in bdev_try_to_free_page() have
a lot of use-after-free issues when umount filesystem concurrently, an

jbd2,ext4: add a shrinker to release checkpointed buffers

Current metadata buffer release logic in bdev_try_to_free_page() have
a lot of use-after-free issues when umount filesystem concurrently, and
it is difficult to fix directly because ext4 is the only user of
s_op->bdev_try_to_free_page callback and we may have to add more special
refcount or lock that is only used by ext4 into the common vfs layer,
which is unacceptable.

One better solution is remove the bdev_try_to_free_page callback, but
the real problem is we cannot easily release journal_head on the
checkpointed buffer, so try_to_free_buffers() cannot release buffers and
page under memory pressure, which is more likely to trigger
out-of-memory. So we cannot remove the callback directly before we find
another way to release journal_head.

This patch introduce a shrinker to free journal_head on the checkpointed
transaction. After the journal_head got freed, try_to_free_buffers()
could free buffer properly.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-6-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

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jbd2: ensure abort the journal if detect IO error when writing original buffer back

Although we merged c044f3d8360 ("jbd2: abort journal if free a async
write error metadata buffer"), there is a rac

jbd2: ensure abort the journal if detect IO error when writing original buffer back

Although we merged c044f3d8360 ("jbd2: abort journal if free a async
write error metadata buffer"), there is a race between
jbd2_journal_try_to_free_buffers() and jbd2_journal_destroy(), so the
jbd2_log_do_checkpoint() may still fail to detect the buffer write
io error flag which may lead to filesystem inconsistency.

jbd2_journal_try_to_free_buffers() ext4_put_super()
jbd2_journal_destroy()
__jbd2_journal_remove_checkpoint()
detect buffer write error jbd2_log_do_checkpoint()
jbd2_cleanup_journal_tail()
<--- lead to inconsistency
jbd2_journal_abort()

Fix this issue by introducing a new atomic flag which only have one
JBD2_CHECKPOINT_IO_ERROR bit now, and set it in
__jbd2_journal_remove_checkpoint() when freeing a checkpoint buffer
which has write_io_error flag. Then jbd2_journal_destroy() will detect
this mark and abort the journal to prevent updating log tail.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-3-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...