ocfs2: convert to new timestamp accessors

Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-54-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

ocfs2: convert to ctime accessor functions

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-60-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ocfs2: fix non-auto defrag path not working issue

This fixes three issues on move extents ioctl without auto defrag:

a) In ocfs2_find_victim_alloc_group(), we have to convert bits to block
first in case of global bitmap.

b) In ocfs2_probe_alloc_group(), when finding enough bits in block
group bitmap, we have to back off move_len to start pos as well,
otherwise it may corrupt filesystem.

c) In ocfs2_ioctl_move_extents(), set me_threshold both for non-auto
and auto defrag paths. Otherwise it will set move_max_hop to 0 and
finally cause unexpectedly ENOSPC error.

Currently there are no tools triggering the above issues since
defragfs.ocfs2 enables auto defrag by default. Tested with manually
changing defragfs.ocfs2 to run non auto defrag path.

Link: https://lkml.kernel.org/r/20230220050526.22020-1-heming.zhao@suse.com
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ocfs2: fix defrag path triggering jbd2 ASSERT

code path:

ocfs2_ioctl_move_extents
ocfs2_move_extents
ocfs2_defrag_extent
__ocfs2_move_extent
+ ocfs2_journal_access_di
+ ocfs2_split_extent //sub-paths call jbd2_journal_restart
+ ocfs2_journal_dirty //crash by jbs2 ASSERT

crash stacks:

PID: 11297 TASK: ffff974a676dcd00 CPU: 67 COMMAND: "defragfs.ocfs2"
#0 [ffffb25d8dad3900] machine_kexec at ffffffff8386fe01
#1 [ffffb25d8dad3958] __crash_kexec at ffffffff8395959d
#2 [ffffb25d8dad3a20] crash_kexec at ffffffff8395a45d
#3 [ffffb25d8dad3a38] oops_end at ffffffff83836d3f
#4 [ffffb25d8dad3a58] do_trap at ffffffff83833205
#5 [ffffb25d8dad3aa0] do_invalid_op at ffffffff83833aa6
#6 [ffffb25d8dad3ac0] invalid_op at ffffffff84200d18
[exception RIP: jbd2_journal_dirty_metadata+0x2ba]
RIP: ffffffffc09ca54a RSP: ffffb25d8dad3b70 RFLAGS: 00010207
RAX: 0000000000000000 RBX: ffff9706eedc5248 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffff97337029ea28 RDI: ffff9706eedc5250
RBP: ffff9703c3520200 R8: 000000000f46b0b2 R9: 0000000000000000
R10: 0000000000000001 R11: 00000001000000fe R12: ffff97337029ea28
R13: 0000000000000000 R14: ffff9703de59bf60 R15: ffff9706eedc5250
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#7 [ffffb25d8dad3ba8] ocfs2_journal_dirty at ffffffffc137fb95 [ocfs2]
#8 [ffffb25d8dad3be8] __ocfs2_move_extent at ffffffffc139a950 [ocfs2]
#9 [ffffb25d8dad3c80] ocfs2_defrag_extent at ffffffffc139b2d2 [ocfs2]

Analysis

This bug has the same root cause of 'commit 7f27ec978b0e ("ocfs2: call
ocfs2_journal_access_di() before ocfs2_journal_dirty() in
ocfs2_write_end_nolock()")'. For this bug, jbd2_journal_restart() is
called by ocfs2_split_extent() during defragmenting.

How to fix

For ocfs2_split_extent() can handle journal operations totally by itself.
Caller doesn't need to call journal access/dirty pair, and caller only
needs to call journal start/stop pair. The fix method is to remove
journal access/dirty from __ocfs2_move_extent().

The discussion for this patch:
https://oss.oracle.com/pipermail/ocfs2-devel/2023-February/000647.html

Link: https://lkml.kernel.org/r/20230217003717.32469-1-heming.zhao@suse.com
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

treewide: remove editor modelines and cruft

The section "19) Editor modelines and other cruft" in
Documentation/process/coding-style.rst clearly says, "Do not include any
of these in source files."

I recently receive a patch to explicitly add a new one.

Let's do treewide cleanups, otherwise some people follow the existing code
and attempt to upstream their favoriate editor setups.

It is even nicer if scripts/checkpatch.pl can check it.

If we like to impose coding style in an editor-independent manner, I think
editorconfig (patch [1]) is a saner solution.

[1] https://lore.kernel.org/lkml/20200703073143.423557-1-danny@kdrag0n.dev/

Link: https://lkml.kernel.org/r/20210324054457.1477489-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org> [auxdisplay]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ocfs2: fix deadlock caused by ocfs2_defrag_extent()

ocfs2_defrag_extent may fall into deadlock.

ocfs2_ioctl_move_extents
ocfs2_ioctl_move_extents
ocfs2_move_extents
ocfs2_defrag_extent
ocfs2_lock_allocators_move_extents

ocfs2_reserve_clusters
inode_lock GLOBAL_BITMAP_SYSTEM_INODE

__ocfs2_flush_truncate_log
inode_lock GLOBAL_BITMAP_SYSTEM_INODE

As backtrace shows above, ocfs2_reserve_clusters() will call inode_lock
against the global bitmap if local allocator has not sufficient cluters.
Once global bitmap could meet the demand, ocfs2_reserve_cluster will
return success with global bitmap locked.

After ocfs2_reserve_cluster(), if truncate log is full,
__ocfs2_flush_truncate_log() will definitely fall into deadlock because
it needs to inode_lock global bitmap, which has already been locked.

To fix this bug, we could remove from
ocfs2_lock_allocators_move_extents() the code which intends to lock
global allocator, and put the removed code after
__ocfs2_flush_truncate_log().

ocfs2_lock_allocators_move_extents() is referred by 2 places, one is
here, the other does not need the data allocator context, which means
this patch does not affect the caller so far.

Link: http://lkml.kernel.org/r/20181101071422.14470-1-lchen@suse.com
Signed-off-by: Larry Chen <lchen@suse.com>
Reviewed-by: Changwei Ge <ge.changwei@h3c.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: fix clusters leak in ocfs2_defrag_extent()

ocfs2_defrag_extent() might leak allocated clusters. When the file
system has insufficient space, the number of claimed clusters might be
less than the caller wants. If that happens, the original code might
directly commit the transaction without returning clusters.

This patch is based on code in ocfs2_add_clusters_in_btree().

[akpm@linux-foundation.org: include localalloc.h, reduce scope of data_ac]
Link: http://lkml.kernel.org/r/20180904041621.16874-3-lchen@suse.com
Signed-off-by: Larry Chen <lchen@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: clean up some dead code

clean up some unused functions and parameters.

Link: http://lkml.kernel.org/r/598A5E21.2080807@huawei.com
Signed-off-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Alex Chen <alex.chen@huawei.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: convert inode refcount test to a helper

Replace the open-coded inode refcount flag test with a helper function
to reduce the potential for bugs.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs: Replace CURRENT_TIME with current_time() for inode timestamps

CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

wrappers for ->i_mutex access

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ocfs2: neaten do_error, ocfs2_error and ocfs2_abort

These uses sometimes do and sometimes don't have '\n' terminations. Make
the uses consistently use '\n' terminations and remove the newline from
the functions.

Miscellanea:

o Coalesce formats
o Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: acknowledge return value of ocfs2_error()

Caveat: This may return -EROFS for a read case, which seems wrong. This
is happening even without this patch series though. Should we convert
EROFS to EIO?

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: remove bogus NULL check in ocfs2_move_extents()

"inode" isn't NULL here, and also we dereference it on the previous line
so static checkers get annoyed.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: fix shift left operations overflow

ocfs2_inode_info->ip_clusters and ocfs2_dinode->id1.bitmap1.i_total are
defined as type u32, so the shift left operations may overflow if volume
size is large, for example, 2TB and cluster size is 1MB.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Alex Chen <alex.chen@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: correctly check the return value of ocfs2_search_extent_list

ocfs2_search_extent_list may return -1, so we should check the return
value in ocfs2_split_and_insert, otherwise it may cause array index out of
bound.

And ocfs2_search_extent_list can only return value less than
el->l_next_free_rec, so check if it is equal or larger than
le16_to_cpu(el->l_next_free_rec) is meaningless.

Signed-off-by: Yingtai Xie <xieyingtai@huawei.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: rollback alloc_dinode counts when ocfs2_block_group_set_bits() failed

After updating alloc_dinode counts in ocfs2_alloc_dinode_update_counts(),
if ocfs2_alloc_dinode_update_bitmap() failed, there is a rare case that
some space may be lost.

So, roll back alloc_dinode counts when ocfs2_block_group_set_bits()
failed.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Younger Liu <younger.liucn@gmail.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: call ocfs2_update_inode_fsync_trans when updating any inode

Ensure that ocfs2_update_inode_fsync_trans() is called any time we touch
an inode in a given transaction. This is a follow-on to the previous
patch to reduce lock contention and deadlocking during an fsync
operation.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Wengang <wen.gang.wang@oracle.com>
Cc: Greg Marsden <greg.marsden@oracle.com>
Cc: Srinivas Eeda <srinivas.eeda@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: remove redundant ocfs2_alloc_dinode_update_counts() and ocfs2_block_group_set_bits()

ocfs2_alloc_dinode_update_counts() and ocfs2_block_group_set_bits() are
already provided in suballoc.c. So, the same functions in
move_extents.c are not needed any more.

Declare the functions in suballoc.h and remove redundant functions in
move_extents.c.

Signed-off-by: Younger Liu <liuyiyang@hisense.com>
Cc: Younger Liu <younger.liucn@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: add missing errno in ocfs2_ioctl_move_extents()

If the file is not regular or writeable, it should return errno(EPERM).

This patch is based on 85a258b70d ("ocfs2: fix error handling in
ocfs2_ioctl_move_extents()").

Signed-off-by: Younger Liu <younger.liu@huawei.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ocfs2: remove unnecessary variable bits_wanted from ocfs2_calc_extend_credits

Code cleanup to remove unnecessary variable passed but never used
to ocfs2_calc_extend_credits.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: fix a memory leak in __ocfs2_move_extents()

The ocfs2 path is not properly freed which leads to a memory leak at
__ocfs2_move_extents().

This patch stops the leaks of the ocfs2_path structure.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Younger Liu <younger.liu@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: use i_size_read() to access i_size

Though ocfs2 uses inode->i_mutex to protect i_size, there are both
i_size_read/write() and direct accesses. Clean up all direct access to
eliminate confusion.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Jie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: fix NULL pointer dereference in ocfs2_duplicate_clusters_by_page

Since ocfs2_cow_file_pos will invoke ocfs2_refcount_icow with a NULL as
the struct file pointer, it finally result in a null pointer dereference
in ocfs2_duplicate_clusters_by_page.

This patch replace file pointer with inode pointer in
cow_duplicate_clusters to fix this issue.

[jeff.liu@oracle.com: rebased patch against linux-next tree]
Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: Tao Ma <tm@tao.ma>
Tested-by: David Weber <wb@munzinger.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: fix NULL dereference for moving extents

We can't dereference "bg" before it has been assigned. GCC should have
warned about this but "bg" was initialized to NULL. I've fixed that as
well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: fix error handling in ocfs2_ioctl_move_extents()

Smatch complains that if we hit an error (for example if the file is
immutable) then "range" has uninitialized stack data and we copy it to
the user.

I've re-written the error handling to avoid this problem and make it a
little cleaner as well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ocfs2: deal with __user misannotations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfs: mnt_drop_write_file()

new helper (wrapper around mnt_drop_write()) to be used in pair with
mnt_want_write_file().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

switch a bunch of places to mnt_want_write_file()

it's both faster (in case when file has been opened for write) and cleaner.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

treewide: remove duplicate includes

Many stupid corrections of duplicated includes based on the output of
scripts/checkincludes.pl.

Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

ocfs2: checking the wrong variable in ocfs2_move_extent()

"new_phys_cpos" is always a valid pointer here.
ocfs2_probe_alloc_group() allocates "*new_phys_cpos".

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>

Ocfs2/move_extents: Validate moving goal after the adjustment.

though the goal_to_be_moved will be validated again in following moving, it's
still a good idea to validate it after adjustment at the very beginning, instead
of validating it before adjustment.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: Avoid doing division in extent moving.

It's not wise enough to do a 64bits division anywhere in kernside, replace it
with a decent helper or proper shifts.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: Set several trivial constraints for threshold.

The threshold should be greater than clustersize and less than i_size.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: Let defrag handle partial extent moving.

We're going to support partial extent moving, which may split entire extent
movement into pieces to compromise the insuffice allocations, it eases the
'ENSPC' pain and makes the whole moving much less likely to fail, the downside
is it may make the fs even more fragmented before moving, just let the userspace
make a trade-off here.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: move/defrag extents within a certain range.

the basic logic of moving extents for a file is pretty like punching-hole
sequence, walk the extents within the range as user specified, calculating
an appropriate len to defrag/move, then let ocfs2_defrag/move_extent() to
do the actual moving.

This func ends up setting 'OCFS2_MOVE_EXT_FL_COMPLETE' to userpace if operation
gets done successfully.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: helper to calculate the defraging length in one run.

The helper is to calculate the defrag length in one run according to a threshold,
it will proceed doing defragmentation until the threshold was meet, and skip a
LARGE extent if any.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: move entire/partial extent.

ocfs2_move_extent() logic will validate the goal_offset_in_block,
where extents to be moved, what's more, it also compromises a bit
to probe the appropriate region around given goal_offset when the
original goal is not able to fit the movement.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: helpers to update the group descriptor and global bitmap inode.

These helpers were actually borrowed from alloc.c, which may be publicized
later.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: helper to probe a proper region to move in an alloc group.

Before doing the movement of extents, we'd better probe the alloc group from
'goal_blk' for searching a contiguous region to fit the wanted movement, we
even will have a best-effort try by compromising to a threshold around the
given goal.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: helper to validate and adjust moving goal.

First best-effort attempt to validate and adjust the goal (physical address in
block), while it can't guarantee later operation can succeed all the time since
global_bitmap may change a bit over time.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: find the victim alloc group, where the given #blk fits.

This function tries locate the right alloc group, where a given physical block
resides, it returns the caller a buffer_head of victim group descriptor, and also
the offset of block in this group, by passing the block number.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: defrag a range of extent.

It's a relatively complete function to accomplish defragmentation for entire
or partial extent, one journal handle was kept during the operation, it was
logically doing one more thing than ocfs2_move_extent() acutally, yes, it's
claiming the new clusters itself;-)

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: move a range of extent.

The moving range of __ocfs2_move_extent() was within one extent always, it
consists following parts:

1. Duplicates the clusters in pages to new_blkoffset, where extent to be moved.

2. Split the original extent with new extent, coalecse the nearby extents if possible.

3. Append old clusters to truncate log, or decrease_refcount if the extent was refcounted.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: lock allocators and reserve metadata blocks and data clusters for extents moving.

ocfs2_lock_allocators_move_extents() was like the common ocfs2_lock_allocators(),
to lock metadata and data alloctors during extents moving, reserve appropriate
metadata blocks and data clusters, also performa a best- effort to calculate the
credits for journal transaction in one run of movement.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Ocfs2/move_extents: Add basic framework and source files for extent moving.

Adding new files move_extents.[c|h] and fill it with nothing but
only a context structure.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>