Commit Graph

231 Commits

Author SHA1 Message Date
Harshad Shirwadkar 0ee66ddcf3 jbd2: don't touch buffer state until it is filled
Fast commit buffers should be filled in before toucing their
state. Remove code that sets buffer state as dirty before the buffer
is passed to the file system.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201106035911.1942128-12-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-11-06 23:01:04 -05:00
Harshad Shirwadkar 0bce577bf9 jbd2: don't pass tid to jbd2_fc_end_commit_fallback()
In jbd2_fc_end_commit_fallback(), we know which tid to commit. There's
no need for caller to pass it.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201106035911.1942128-10-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-11-06 23:01:03 -05:00
Harshad Shirwadkar c460e5edc8 jbd2: don't use state lock during commit path
Variables journal->j_fc_off, journal->j_fc_wbuf are accessed during
commit path. Since today we allow only one process to perform a fast
commit, there is no need take state lock before accessing these
variables. This patch removes these locks and adds comments to
describe this.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201106035911.1942128-9-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-11-06 23:01:03 -05:00
Harshad Shirwadkar a1e5e465b3 ext4: clean up the JBD2 API that initializes fast commits
This patch removes jbd2_fc_init() API and its related functions to
simplify enabling fast commits. With this change, the number of fast
commit blocks to use is solely determined by the JBD2 layer. So, we
move the default value for minimum number of fast commit blocks from
ext4/fast_commit.h to include/linux/jbd2.h. However, whether or not to
use fast commits is determined by the file system. The file system
just sets the fast commit feature using
jbd2_journal_set_features(). JBD2 layer then determines how many
blocks to use for fast commits (based on the value found in the JBD2
superblock).

Note that the JBD2 feature flag of fast commits is just an indication
that there are fast commit blocks present on disk. It doesn't tell
JBD2 layer about the intent of the file system of whether to it wants
to use fast commit or not. That's why, we blindly clear the fast
commit flag in journal_reset() after the recovery is done.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201106035911.1942128-7-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-11-06 23:01:03 -05:00
Harshad Shirwadkar ede7dc7fa0 jbd2: rename j_maxlen to j_total_len and add jbd2_journal_max_txn_bufs
The on-disk superblock field sb->s_maxlen represents the total size of
the journal including the fast commit area and is no more the max
number of blocks available for a transaction. The maximum number of
blocks available to a transaction is reduced by the number of fast
commit blocks. So, this patch renames j_maxlen to j_total_len to
better represent its intent. Also, it adds a function to calculate max
number of bufs available for a transaction.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201106035911.1942128-6-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-11-06 23:01:02 -05:00
Harshad Shirwadkar ff780b91ef jbd2: add fast commit machinery
This functions adds necessary APIs needed in JBD2 layer for fast
commits.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-5-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-10-21 23:22:37 -04:00
Harshad Shirwadkar 6866d7b3f2 ext4 / jbd2: add fast commit initialization
This patch adds fast commit area trackers in the journal_t
structure. These are initialized via the jbd2_fc_init() routine that
this patch adds. This patch also adds ext4/fast_commit.c and
ext4/fast_commit.h files for fast commit code that will be added in
subsequent patches in this series.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-4-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-10-21 23:22:26 -04:00
Mauricio Faria de Oliveira aa3c0c61f6 jbd2: introduce/export functions jbd2_journal_submit|finish_inode_data_buffers()
Export functions that implement the current behavior done
for an inode in journal_submit|finish_inode_data_buffers().

No functional change.

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/20201006004841.600488-2-mfo@canonical.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-10-18 10:37:15 -04:00
Xianting Tian 60ed633f51 jbd2: fix incorrect code style
Remove unnecessary blank.

Signed-off-by: Xianting Tian <xianting_tian@126.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/1595077057-8048-1-git-send-email-xianting_tian@126.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-07 14:12:35 -04:00
zhangyi (F) ef3f5830b8 jbd2: add the missing unlock_buffer() in the error path of jbd2_write_superblock()
jbd2_write_superblock() is under the buffer lock of journal superblock
before ending that superblock write, so add a missing unlock_buffer() in
in the error path before submitting buffer.

Fixes: 742b06b562 ("jbd2: check superblock mapped prior to committing")
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20200620061948.2049579-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-06 00:15:58 -04:00
zhangyi (F) 7b97d868b7 ext4, jbd2: ensure panic by fix a race between jbd2 abort and ext4 error handlers
In the ext4 filesystem with errors=panic, if one process is recording
errno in the superblock when invoking jbd2_journal_abort() due to some
error cases, it could be raced by another __ext4_abort() which is
setting the SB_RDONLY flag but missing panic because errno has not been
recorded.

jbd2_journal_commit_transaction()
 jbd2_journal_abort()
  journal->j_flags |= JBD2_ABORT;
  jbd2_journal_update_sb_errno()
                                    | ext4_journal_check_start()
                                    |  __ext4_abort()
                                    |   sb->s_flags |= SB_RDONLY;
                                    |   if (!JBD2_REC_ERR)
                                    |        return;
  journal->j_flags |= JBD2_REC_ERR;

Finally, it will no longer trigger panic because the filesystem has
already been set read-only. Fix this by introduce j_abort_mutex to make
sure journal abort is completed before panic, and remove JBD2_REC_ERR
flag.

Fixes: 4327ba52af ("ext4, jbd2: ensure entering into panic after recording an error in superblock")
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200609073540.3810702-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-06-12 14:51:41 -04:00
Linus Torvalds 236f453294 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:

 - bmap series from cmaiolino

 - getting rid of convolutions in copy_mount_options() (use a couple of
   copy_from_user() instead of the __get_user() crap)

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  saner copy_mount_options()
  fibmap: Reject negative block numbers
  fibmap: Use bmap instead of ->bmap method in ioctl_fibmap
  ecryptfs: drop direct calls to ->bmap
  cachefiles: drop direct usage of ->bmap method.
  fs: Enable bmap() function to properly return errors
2020-02-08 13:04:49 -08:00
Alexey Dobriyan 97a32539b9 proc: convert everything to "struct proc_ops"
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Carlos Maiolino 30460e1ea3 fs: Enable bmap() function to properly return errors
By now, bmap() will either return the physical block number related to
the requested file offset or 0 in case of error or the requested offset
maps into a hole.
This patch makes the needed changes to enable bmap() to proper return
errors, using the return value as an error return, and now, a pointer
must be passed to bmap() to be filled with the mapped physical block.

It will change the behavior of bmap() on return:

- negative value in case of error
- zero on success or map fell into a hole

In case of a hole, the *block will be zero too

Since this is a prep patch, by now, the only error return is -EINVAL if
->bmap doesn't exist.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-03 08:05:37 -05:00
zhangyi (F) 7f6225e446 jbd2: clean __jbd2_journal_abort_hard() and __journal_abort_soft()
__jbd2_journal_abort_hard() is no longer used, so now we can merge
__jbd2_journal_abort_hard() and __journal_abort_soft() these two
functions into jbd2_journal_abort() and remove them.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191204124614.45424-5-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-25 03:01:56 -05:00
zhangyi (F) 0e98c084a2 jbd2: make sure ESHUTDOWN to be recorded in the journal superblock
Commit fb7c02445c ("ext4: pass -ESHUTDOWN code to jbd2 layer") want
to allow jbd2 layer to distinguish shutdown journal abort from other
error cases. So the ESHUTDOWN should be taken precedence over any other
errno which has already been recoded after EXT4_FLAGS_SHUTDOWN is set,
but it only update errno in the journal suoerblock now if the old errno
is 0.

Fixes: fb7c02445c ("ext4: pass -ESHUTDOWN code to jbd2 layer")
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191204124614.45424-4-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-25 03:00:20 -05:00
zhangyi (F) 51f57b01e4 ext4, jbd2: ensure panic when aborting with zero errno
JBD2_REC_ERR flag used to indicate the errno has been updated when jbd2
aborted, and then __ext4_abort() and ext4_handle_error() can invoke
panic if ERRORS_PANIC is specified. But if the journal has been aborted
with zero errno, jbd2_journal_abort() didn't set this flag so we can
no longer panic. Fix this by always record the proper errno in the
journal superblock.

Fixes: 4327ba52af ("ext4, jbd2: ensure entering into panic after recording an error in superblock")
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191204124614.45424-3-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-25 02:59:25 -05:00
Vasily Averin 1a8e9cf40c jbd2_seq_info_next should increase position index
if seq_file .next fuction does not change position index,
read after some lseek can generate unexpected output.

Script below generates endless output
 $ q=;while read -r r;do echo "$((++q)) $r";done </proc/fs/jbd2/DEV/info

https://bugzilla.kernel.org/show_bug.cgi?id=206283

Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code and interface")
Cc: stable@kernel.org
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/d13805e5-695e-8ac3-b678-26ca2313629f@virtuozzo.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-25 02:30:46 -05:00
Shijie Luo 17c51d836c jbd2: remove pointless assertion in __journal_remove_journal_head
Only when jh->b_jcount = 0 in jbd2_journal_put_journal_head, we are allowed
to call __journal_remove_journal_head. This assertion is meaningless,
just remove it.

Signed-off-by: Shijie Luo <luoshijie1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200123070054.50585-1-luoshijie1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-25 02:25:56 -05:00
Kai Li a09decff5c jbd2: clear JBD2_ABORT flag before journal_reset to update log tail info when load journal
If the journal is dirty when the filesystem is mounted, jbd2 will replay
the journal but the journal superblock will not be updated by
journal_reset() because JBD2_ABORT flag is still set (it was set in
journal_init_common()). This is problematic because when a new transaction
is then committed, it will be recorded in block 1 (journal->j_tail was set
to 1 in journal_reset()). If unclean shutdown happens again before the
journal superblock is updated, the new recorded transaction will not be
replayed during the next mount (because of stale sb->s_start and
sb->s_sequence values) which can lead to filesystem corruption.

Fixes: 85e0c4e89c ("jbd2: if the journal is aborted then don't allow update of the log tail")
Signed-off-by: Kai Li <li.kai4@h3c.com>
Link: https://lore.kernel.org/r/20200111022542.5008-1-li.kai4@h3c.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-17 16:25:47 -05:00
Theodore Ts'o a6d4040846 Merge branch 'jk/jbd2-revoke-overflow' 2019-11-05 16:02:20 -05:00
Jan Kara fdc3ef882a jbd2: Reserve space for revoke descriptor blocks
Extend functions for starting, extending, and restarting transaction
handles to take number of revoke records handle must be able to
accommodate. These functions then make sure transaction has enough
credits to be able to store resulting revoke descriptor blocks. Also
revoke code tracks number of revoke records created by a handle to catch
situation where some place didn't reserve enough space for revoke
records. Similarly to standard transaction credits, space for unused
reserved revoke records is released when the handle is stopped.

On the ext4 side we currently take a simplistic approach of reserving
space for 1024 revoke records for any transaction. This grows amount of
credits reserved for each handle only by a few and is enough for any
normal workload so that we don't hit warnings in jbd2. We will refine
the logic in following commits.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-20-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara 9f356e5a4f jbd2: Account descriptor blocks into t_outstanding_credits
Currently, journal descriptor blocks were not accounted in
transaction->t_outstanding_credits and we were just leaving some slack
space in the journal for them (in jbd2_log_space_left() and
jbd2_space_needed()). This is making proper accounting (and reservation
we want to add) of descriptor blocks difficult so switch to accounting
descriptor blocks in transaction->t_outstanding_credits and just reserve
the same amount of credits in t_outstanding credits for journal
descriptor blocks when creating transaction.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-18-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara b90bfdf581 jbd2: Completely fill journal descriptor blocks
With 32-bit block numbers, we don't allocate the array for journal
buffer heads large enough for corresponding descriptor tags to fill the
descriptor block. Thus we end up writing out half-full descriptor blocks
to the journal unnecessarily growing the transaction. Fix the logic to
allocate the array large enough.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 12:13:25 -05:00
Thomas Gleixner 7855a57d00 jbd2: Free journal head outside of locked region
On PREEMPT_RT bit-spinlocks have the same semantics as on PREEMPT_RT=n,
i.e. they disable preemption. That means functions which are not safe to be
called in preempt disabled context on RT trigger a might_sleep() assert.

The journal head bit spinlock is mostly held for short code sequences with
trivial RT safe functionality, except for one place:

jbd2_journal_put_journal_head() invokes __journal_remove_journal_head()
with the journal head bit spinlock held. __journal_remove_journal_head()
invokes kmem_cache_free() which must not be called with preemption disabled
on RT.

Jan suggested to rework the removal function so the actual free happens
outside the bit-spinlocked region.

Split it into two parts:

  - Do the sanity checks and the buffer head detach under the lock

  - Do the actual free after dropping the lock

There is error case handling in the free part which needs to dereference
the b_size field of the now detached buffer head. Due to paranoia (caused
by ignorance) the size is retrieved in the detach function and handed into
the free function. Might be over-engineered, but better safe than sorry.

This makes the journal head bit-spinlock usage RT compliant and also avoids
nested locking which is not covered by lockdep.

Suggested-by: Jan Kara <jack@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-ext4@vger.kernel.org
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan Kara <jack@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20190809124233.13277-8-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-21 09:16:46 -04:00
Thomas Gleixner 464170647b jbd2: Make state lock a spinlock
Bit-spinlocks are problematic on PREEMPT_RT if functions which might sleep
on RT, e.g. spin_lock(), alloc/free(), are invoked inside the lock held
region because bit spinlocks disable preemption even on RT.

A first attempt was to replace state lock with a spinlock placed in struct
buffer_head and make the locking conditional on PREEMPT_RT and
DEBUG_BIT_SPINLOCKS.

Jan pointed out that there is a 4 byte hole in struct journal_head where a
regular spinlock fits in and he would not object to convert the state lock
to a spinlock unconditionally.

Aside of solving the RT problem, this also gains lockdep coverage for the
journal head state lock (bit-spinlocks are not covered by lockdep as it's
hard to fit a lockdep map into a single bit).

The trivial change would have been to convert the jbd_*lock_bh_state()
inlines, but that comes with the downside that these functions take a
buffer head pointer which needs to be converted to a journal head pointer
which adds another level of indirection.

As almost all functions which use this lock have a journal head pointer
readily available, it makes more sense to remove the lock helper inlines
and write out spin_*lock() at all call sites.

Fixup all locking comments as well.

Suggested-by: Jan Kara <jack@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jan Kara <jack@suse.com>
Cc: linux-ext4@vger.kernel.org
Link: https://lore.kernel.org/r/20190809124233.13277-7-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-21 09:16:46 -04:00
Joseph Qi 963abb9aeb jbd2: remove jbd2_journal_inode_add_[write|wait]
Since ext4/ocfs2 are using jbd2_inode dirty range scoping APIs now,
jbd2_journal_inode_add_[write|wait] are not used any more, remove them.

Link: http://lkml.kernel.org/r/1562977611-8412-2-git-send-email-joseph.qi@linux.alibaba.com
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Ross Zwisler <zwisler@google.com>
Acked-by: Changwei Ge <chge@linux.alibaba.com>
Cc: Gang He <ghe@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24 15:54:07 -07:00
Theodore Ts'o 9382cde8cd jbd2: drop declaration of journal_sync_buffer()
The journal_sync_buffer() function was never carried over from jbd to
jbd2.  So get rid of the vestigal declaration of this (non-existent)
function.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-20 17:32:21 -04:00
Ross Zwisler 6ba0e7dc64 jbd2: introduce jbd2_inode dirty range scoping
Currently both journal_submit_inode_data_buffers() and
journal_finish_inode_data_buffers() operate on the entire address space
of each of the inodes associated with a given journal entry.  The
consequence of this is that if we have an inode where we are constantly
appending dirty pages we can end up waiting for an indefinite amount of
time in journal_finish_inode_data_buffers() while we wait for all the
pages under writeback to be written out.

The easiest way to cause this type of workload is do just dd from
/dev/zero to a file until it fills the entire filesystem.  This can
cause journal_finish_inode_data_buffers() to wait for the duration of
the entire dd operation.

We can improve this situation by scoping each of the inode dirty ranges
associated with a given transaction.  We do this via the jbd2_inode
structure so that the scoping is contained within jbd2 and so that it
follows the lifetime and locking rules for that structure.

This allows us to limit the writeback & wait in
journal_submit_inode_data_buffers() and
journal_finish_inode_data_buffers() respectively to the dirty range for
a given struct jdb2_inode, keeping us from waiting forever if the inode
in question is still being appended to.

Signed-off-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
2019-06-20 17:24:56 -04:00
Gaowei Pu 7821ce417e jbd2: fix some print format mistakes
There are some print format mistakes in debug messages. Fix them.

Signed-off-by: Gaowei Pu <pugaowei@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2019-05-30 15:08:34 -04:00
Chengguang Xu 0d52154bb0 jbd2: fix potential double free
When failing from creating cache jbd2_inode_cache, we will destroy the
previously created cache jbd2_handle_cache twice.  This patch fixes
this by moving each cache initialization/destruction to its own
separate, individual function.

Signed-off-by: Chengguang Xu <cgxu519@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2019-05-10 21:15:47 -04:00
Jiufei Xue 742b06b562 jbd2: check superblock mapped prior to committing
We hit a BUG at fs/buffer.c:3057 if we detached the nbd device
before unmounting ext4 filesystem.

The typical chain of events leading to the BUG:
jbd2_write_superblock
  submit_bh
    submit_bh_wbc
      BUG_ON(!buffer_mapped(bh));

The block device is removed and all the pages are invalidated. JBD2
was trying to write journal superblock to the block device which is
no longer present.

Fix this by checking the journal superblock's buffer head prior to
submitting.

Reported-by: Eric Ren <renzhen@linux.alibaba.com>
Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
2019-04-06 18:57:40 -04:00
Theodore Ts'o a58ca99266 jbd2: fold jbd2_superblock_csum_{verify,set} into their callers
The functions jbd2_superblock_csum_verify() and
jbd2_superblock_csum_set() only get called from one location, so to
simplify things, fold them into their callers.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-02-14 16:28:14 -05:00
Theodore Ts'o 538bcaa626 jbd2: fix race when writing superblock
The jbd2 superblock is lockless now, so there is probably a race
condition between writing it so disk and modifing contents of it, which
may lead to checksum error. The following race is the one case that we
have captured.

jbd2                                fsstress
jbd2_journal_commit_transaction
 jbd2_journal_update_sb_log_tail
  jbd2_write_superblock
   jbd2_superblock_csum_set         jbd2_journal_revoke
                                     jbd2_journal_set_features(revork)
                                     modify superblock
   submit_bh(checksum incorrect)

Fix this by locking the buffer head before modifing it.  We always
write the jbd2 superblock after we modify it, so this just means
calling the lock_buffer() a little earlier.

This checksum corruption problem can be reproduced by xfstests
generic/475.

Reported-by: zhangyi (F) <yi.zhang@huawei.com>
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-02-14 16:27:14 -05:00
Xiaoguang Wang 53cf978457 jbd2: fix deadlock while checkpoint thread waits commit thread to finish
This issue was found when I tried to put checkpoint work in a separate thread,
the deadlock below happened:
         Thread1                                |   Thread2
__jbd2_log_wait_for_space                       |
jbd2_log_do_checkpoint (hold j_checkpoint_mutex)|
  if (jh->b_transaction != NULL)                |
    ...                                         |
    jbd2_log_start_commit(journal, tid);        |jbd2_update_log_tail
                                                |  will lock j_checkpoint_mutex,
                                                |  but will be blocked here.
                                                |
    jbd2_log_wait_commit(journal, tid);         |
    wait_event(journal->j_wait_done_commit,     |
     !tid_gt(tid, journal->j_commit_sequence)); |
     ...                                        |wake_up(j_wait_done_commit)
  }                                             |

then deadlock occurs, Thread1 will never be waken up.

To fix this issue, drop j_checkpoint_mutex in jbd2_log_do_checkpoint()
when we are going to wait for transaction commit.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-01-31 23:42:11 -05:00
Wang Long 8bdd5b60e0 jbd2: remove NULL check before calling kmem_cache_destroy()
The kmem_cache_destroy() function already checks for null pointers, so
we can remove the check at the call site.

This patch also sets jbd2_handle_cache and jbd2_inode_cache to be NULL
after freeing them in jbd2_journal_destroy_handle_cache().

Signed-off-by: Wang Long <wanglong19@meituan.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2018-05-20 22:38:26 -04:00
Wang Shilong 9196f57151 jbd2: remove bunch of empty lines with jbd2 debug
See following dmesg output with jbd2 debug enabled:

...(start_this_handle, 313): New handle 00000000c88d6ceb going live.

...(start_this_handle, 383): Handle 00000000c88d6ceb given 53 credits (total 53, free 32681)

...(do_get_write_access, 838): journal_head 0000000002856fc0, force_copy 0

...(jbd2_journal_cancel_revoke, 421): journal_head 0000000002856fc0, cancelling revoke

We have an extra line with every messages, this is a waste of buffer,
we can fix it by removing "\n" in the caller or remove it in
the __jbd2_debug(), i checked every jbd2_debug() passed '\n' explicitly.

To avoid more lines, let's remove it inside __jbd2_debug().

Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2018-05-20 22:14:29 -04:00
Theodore Ts'o 85e0c4e89c jbd2: if the journal is aborted then don't allow update of the log tail
This updates the jbd2 superblock unnecessarily, and on an abort we
shouldn't truncate the log.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2018-02-19 12:22:53 -05:00
Theodore Ts'o fb7c02445c ext4: pass -ESHUTDOWN code to jbd2 layer
Previously the jbd2 layer assumed that a file system check would be
required after a journal abort.  In the case of the deliberate file
system shutdown, this should not be necessary.  Allow the jbd2 layer
to distinguish between these two cases by using the ESHUTDOWN errno.

Also add proper locking to __journal_abort_soft().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2018-02-18 23:45:18 -05:00
Theodore Ts'o f516676857 ext4: fix up remaining files with SPDX cleanups
A number of ext4 source files were skipped due because their copyright
permission statements didn't match the expected text used by the
automated conversion utilities.  I've added SPDX tags for the rest.

While looking at some of these files, I've noticed that we have quite
a bit of variation on the licenses that were used --- in particular
some of the Red Hat licenses on the jbd2 files use a GPL2+ license,
and we have some files that have a LGPL-2.1 license (which was quite
surprising).

I've not attempted to do any license changes.  Even if it is perfectly
legal to relicense to GPL 2.0-only for consistency's sake, that should
be done with ext4 developer community discussion.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-12-17 22:00:59 -05:00
Linus Torvalds a3841f94c7 libnvdimm for 4.15
* Introduce MAP_SYNC and MAP_SHARED_VALIDATE, a mechanism to enable
  'userspace flush' of persistent memory updates via filesystem-dax
   mappings. It arranges for any filesystem metadata updates that may be
   required to satisfy a write fault to also be flushed ("on disk") before
   the kernel returns to userspace from the fault handler. Effectively
   every write-fault that dirties metadata completes an fsync() before
   returning from the fault handler. The new MAP_SHARED_VALIDATE mapping
   type guarantees that the MAP_SYNC flag is validated as supported by the
   filesystem's ->mmap() file operation.
 
 * Add support for the standard ACPI 6.2 label access methods that
   replace the NVDIMM_FAMILY_INTEL (vendor specific) label methods. This
   enables interoperability with environments that only implement the
   standardized methods.
 
 * Add support for the ACPI 6.2 NVDIMM media error injection methods.
 
 * Add support for the NVDIMM_FAMILY_INTEL v1.6 DIMM commands for latch
   last shutdown status, firmware update, SMART error injection, and
   SMART alarm threshold control.
 
 * Cleanup physical address information disclosures to be root-only.
 
 * Fix revalidation of the DIMM "locked label area" status to support
   dynamic unlock of the label area.
 
 * Expand unit test infrastructure to mock the ACPI 6.2 Translate SPA
   (system-physical-address) command and error injection commands.
 
 Acknowledgements that came after the commits were pushed to -next:
 
 957ac8c421 dax: fix PMD faults on zero-length files
 Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
 
 a39e596baa xfs: support for synchronous DAX faults
 Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
 
 7b565c9f96 xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault()
 Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
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Merge tag 'libnvdimm-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm and dax updates from Dan Williams:
 "Save for a few late fixes, all of these commits have shipped in -next
  releases since before the merge window opened, and 0day has given a
  build success notification.

  The ext4 touches came from Jan, and the xfs touches have Darrick's
  reviewed-by. An xfstest for the MAP_SYNC feature has been through
  a few round of reviews and is on track to be merged.

   - Introduce MAP_SYNC and MAP_SHARED_VALIDATE, a mechanism to enable
     'userspace flush' of persistent memory updates via filesystem-dax
     mappings. It arranges for any filesystem metadata updates that may
     be required to satisfy a write fault to also be flushed ("on disk")
     before the kernel returns to userspace from the fault handler.
     Effectively every write-fault that dirties metadata completes an
     fsync() before returning from the fault handler. The new
     MAP_SHARED_VALIDATE mapping type guarantees that the MAP_SYNC flag
     is validated as supported by the filesystem's ->mmap() file
     operation.

   - Add support for the standard ACPI 6.2 label access methods that
     replace the NVDIMM_FAMILY_INTEL (vendor specific) label methods.
     This enables interoperability with environments that only implement
     the standardized methods.

   - Add support for the ACPI 6.2 NVDIMM media error injection methods.

   - Add support for the NVDIMM_FAMILY_INTEL v1.6 DIMM commands for
     latch last shutdown status, firmware update, SMART error injection,
     and SMART alarm threshold control.

   - Cleanup physical address information disclosures to be root-only.

   - Fix revalidation of the DIMM "locked label area" status to support
     dynamic unlock of the label area.

   - Expand unit test infrastructure to mock the ACPI 6.2 Translate SPA
     (system-physical-address) command and error injection commands.

  Acknowledgements that came after the commits were pushed to -next:

   - 957ac8c421 ("dax: fix PMD faults on zero-length files"):
       Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>

   - a39e596baa ("xfs: support for synchronous DAX faults") and
     7b565c9f96 ("xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault()")
        Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>"

* tag 'libnvdimm-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (49 commits)
  acpi, nfit: add 'Enable Latch System Shutdown Status' command support
  dax: fix general protection fault in dax_alloc_inode
  dax: fix PMD faults on zero-length files
  dax: stop requiring a live device for dax_flush()
  brd: remove dax support
  dax: quiet bdev_dax_supported()
  fs, dax: unify IOMAP_F_DIRTY read vs write handling policy in the dax core
  tools/testing/nvdimm: unit test clear-error commands
  acpi, nfit: validate commands against the device type
  tools/testing/nvdimm: stricter bounds checking for error injection commands
  xfs: support for synchronous DAX faults
  xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault()
  ext4: Support for synchronous DAX faults
  ext4: Simplify error handling in ext4_dax_huge_fault()
  dax: Implement dax_finish_sync_fault()
  dax, iomap: Add support for synchronous faults
  mm: Define MAP_SYNC and VM_SYNC flags
  dax: Allow tuning whether dax_insert_mapping_entry() dirties entry
  dax: Allow dax_iomap_fault() to return pfn
  dax: Fix comment describing dax_iomap_fault()
  ...
2017-11-17 09:51:57 -08:00
Jan Kara b8a6176c21 ext4: Support for synchronous DAX faults
We return IOMAP_F_DIRTY flag from ext4_iomap_begin() when asked to
prepare blocks for writing and the inode has some uncommitted metadata
changes. In the fault handler ext4_dax_fault() we then detect this case
(through VM_FAULT_NEEDDSYNC return value) and call helper
dax_finish_sync_fault() to flush metadata changes and insert page table
entry. Note that this will also dirty corresponding radix tree entry
which is what we want - fsync(2) will still provide data integrity
guarantees for applications not using userspace flushing. And
applications using userspace flushing can avoid calling fsync(2) and
thus avoid the performance overhead.

Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-11-03 06:26:26 -07:00
Kees Cook e3c957885e jbd2: convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.com>
Cc: linux-ext4@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
2017-10-18 12:40:28 -04:00
Ingo Molnar 2141713616 sched/wait: Standardize 'struct wait_bit_queue' wait-queue entry field name
Rename 'struct wait_bit_queue::wait' to ::wq_entry, to more clearly
name it as a wait-queue entry.

Propagate it to a couple of usage sites where the wait-bit-queue internals
are exposed.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:18:28 +02:00
Linus Torvalds de4d195308 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes are:

   - Debloat RCU headers

   - Parallelize SRCU callback handling (plus overlapping patches)

   - Improve the performance of Tree SRCU on a CPU-hotplug stress test

   - Documentation updates

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits)
  rcu: Open-code the rcu_cblist_n_lazy_cbs() function
  rcu: Open-code the rcu_cblist_n_cbs() function
  rcu: Open-code the rcu_cblist_empty() function
  rcu: Separately compile large rcu_segcblist functions
  srcu: Debloat the <linux/rcu_segcblist.h> header
  srcu: Adjust default auto-expediting holdoff
  srcu: Specify auto-expedite holdoff time
  srcu: Expedite first synchronize_srcu() when idle
  srcu: Expedited grace periods with reduced memory contention
  srcu: Make rcutorture writer stalls print SRCU GP state
  srcu: Exact tracking of srcu_data structures containing callbacks
  srcu: Make SRCU be built by default
  srcu: Fix Kconfig botch when SRCU not selected
  rcu: Make non-preemptive schedule be Tasks RCU quiescent state
  srcu: Expedite srcu_schedule_cbs_snp() callback invocation
  srcu: Parallelize callback handling
  kvm: Move srcu_struct fields to end of struct kvm
  rcu: Fix typo in PER_RCU_NODE_PERIOD header comment
  rcu: Use true/false in assignment to bool
  rcu: Use bool value directly
  ...
2017-05-10 10:30:46 -07:00
Linus Torvalds dd727dad37 Add GETFSMAP support; some performance improvements for very large
file systems and for random write workloads into a preallocated file;
 bug fixes and cleanups.
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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:

 - add GETFSMAP support

 - some performance improvements for very large file systems and for
   random write workloads into a preallocated file

 - bug fixes and cleanups.

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: cleanup write flags handling from jbd2_write_superblock()
  ext4: mark superblock writes synchronous for nobarrier mounts
  ext4: inherit encryption xattr before other xattrs
  ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio()
  ext4: avoid unnecessary transaction stalls during writeback
  ext4: preload block group descriptors
  ext4: make ext4_shutdown() static
  ext4: support GETFSMAP ioctls
  vfs: add common GETFSMAP ioctl definitions
  ext4: evict inline data when writing to memory map
  ext4: remove ext4_xattr_check_entry()
  ext4: rename ext4_xattr_check_names() to ext4_xattr_check_entries()
  ext4: merge ext4_xattr_list() into ext4_listxattr()
  ext4: constify static data that is never modified
  ext4: trim return value and 'dir' argument from ext4_insert_dentry()
  jbd2: fix dbench4 performance regression for 'nobarrier' mounts
  jbd2: Fix lockdep splat with generic/270 test
  mm: retry writepages() on ENOMEM when doing an data integrity writeback
2017-05-08 11:30:05 -07:00
Jan Kara 17f423b516 jbd2: cleanup write flags handling from jbd2_write_superblock()
Currently jbd2_write_superblock() silently adds REQ_SYNC to flags with
which journal superblock is written. Make this explicit by making flags
passed down to jbd2_write_superblock() contain REQ_SYNC.

CC: linux-ext4@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:01:31 -04:00
Michal Hocko eb52da3f48 jbd2: make the whole kjournald2 kthread NOFS safe
kjournald2 is central to the transaction commit processing.  As such any
potential allocation from this kernel thread has to be GFP_NOFS.  Make
sure to mark the whole kernel thread GFP_NOFS by the memalloc_nofs_save.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20170306131408.9828-8-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-03 15:52:09 -07:00
Jan Kara 5052b069ac jbd2: fix dbench4 performance regression for 'nobarrier' mounts
Commit b685d3d65a "block: treat REQ_FUA and REQ_PREFLUSH as
synchronous" removed REQ_SYNC flag from WRITE_FUA implementation. Since
JBD2 strips REQ_FUA and REQ_FLUSH flags from submitted IO when the
filesystem is mounted with nobarrier mount option, journal superblock
writes ended up being async writes after this patch and that caused
heavy performance regression for dbench4 benchmark with high number of
processes. In my test setup with HP RAID array with non-volatile write
cache and 32 GB ram, dbench4 runs with 8 processes regressed by ~25%.

Fix the problem by making sure journal superblock writes are always
treated as synchronous since they generally block progress of the
journalling machinery and thus the whole filesystem.

Fixes: b685d3d65a
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-29 21:07:30 -04:00
Jan Kara c52c47e4b4 jbd2: Fix lockdep splat with generic/270 test
I've hit a lockdep splat with generic/270 test complaining that:

3216.fsstress.b/3533 is trying to acquire lock:
 (jbd2_handle){++++..}, at: [<ffffffff813152e0>] jbd2_log_wait_commit+0x0/0x150

but task is already holding lock:
 (jbd2_handle){++++..}, at: [<ffffffff8130bd3b>] start_this_handle+0x35b/0x850

The underlying problem is that jbd2_journal_force_commit_nested()
(called from ext4_should_retry_alloc()) may get called while a
transaction handle is started. In such case it takes care to not wait
for commit of the running transaction (which would deadlock) but only
for a commit of a transaction that is already committing (which is safe
as that doesn't wait for any filesystem locks).

In fact there are also other callers of jbd2_log_wait_commit() that take
care to pass tid of a transaction that is already committing and for
those cases, the lockdep instrumentation is too restrictive and leading
to false positive reports. Fix the problem by calling
jbd2_might_wait_for_commit() from jbd2_log_wait_commit() only if the
transaction isn't already committing.

Fixes: 1eaa566d36
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-29 20:12:16 -04:00