Convert the ext4_has_group_desc_csum predicate to look for a checksum
driver instead of the metadata_csum flag and change the bg checksum
calculation function to look for GDT_CSUM before taking the crc16
path.

Without this patch, if we mount with ^uninit_bg,^metadata_csum and
later metadata_csum gets turned on by accident, the block group
checksum functions will incorrectly assume that checksumming is
enabled (metadata_csum) but that crc16 should be used
(!s_chksum_driver).  This is totally wrong, so fix the predicate
and the checksum formula selection.

(Granted, if the metadata_csum feature bit gets enabled on a live FS
then something underhanded is going on, but we could at least avoid
writing garbage into the on-disk fields.)
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NDmitry Monakhov <dmonakhov@openvz.org>
Cc: stable@vger.kernel.org

Error report likely result in IO so it is bad idea to do it from
atomic context.

This patch should fix following issue:

BUG: sleeping function called from invalid context at include/linux/buffer_head.h:349
in_atomic(): 1, irqs_disabled(): 0, pid: 137, name: kworker/u128:1
5 locks held by kworker/u128:1/137:
 #0:  ("writeback"){......}, at: [<ffffffff81085618>] process_one_work+0x228/0x4d0
 #1:  ((&(&wb->dwork)->work)){......}, at: [<ffffffff81085618>] process_one_work+0x228/0x4d0
 #2:  (jbd2_handle){......}, at: [<ffffffff81242622>] start_this_handle+0x712/0x7b0
 #3:  (&ei->i_data_sem){......}, at: [<ffffffff811fa387>] ext4_map_blocks+0x297/0x430
 #4:  (&(&bgl->locks[i].lock)->rlock){......}, at: [<ffffffff811f3180>] ext4_read_block_bitmap_nowait+0x5d0/0x630
CPU: 3 PID: 137 Comm: kworker/u128:1 Not tainted 3.17.0-rc2-00184-g82752e4 #165
Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011
Workqueue: writeback bdi_writeback_workfn (flush-1:0)
 0000000000000411 ffff880813777288 ffffffff815c7fdc ffff880813777288
 ffff880813a8bba0 ffff8808137772a8 ffffffff8108fb30 ffff880803e01e38
 ffff880803e01e38 ffff8808137772c8 ffffffff811a8d53 ffff88080ecc6000
Call Trace:
 [<ffffffff815c7fdc>] dump_stack+0x51/0x6d
 [<ffffffff8108fb30>] __might_sleep+0xf0/0x100
 [<ffffffff811a8d53>] __sync_dirty_buffer+0x43/0xe0
 [<ffffffff811a8e03>] sync_dirty_buffer+0x13/0x20
 [<ffffffff8120f581>] ext4_commit_super+0x1d1/0x230
 [<ffffffff8120fa03>] save_error_info+0x23/0x30
 [<ffffffff8120fd06>] __ext4_error+0xb6/0xd0
 [<ffffffff8120f260>] ? ext4_group_desc_csum+0x140/0x190
 [<ffffffff811f2d8c>] ext4_read_block_bitmap_nowait+0x1dc/0x630
 [<ffffffff8122e23a>] ext4_mb_init_cache+0x21a/0x8f0
 [<ffffffff8113ae95>] ? lru_cache_add+0x55/0x60
 [<ffffffff8112e16c>] ? add_to_page_cache_lru+0x6c/0x80
 [<ffffffff8122eaa0>] ext4_mb_init_group+0x190/0x280
 [<ffffffff8122ec51>] ext4_mb_good_group+0xc1/0x190
 [<ffffffff8123309a>] ext4_mb_regular_allocator+0x17a/0x410
 [<ffffffff8122c821>] ? ext4_mb_use_preallocated+0x31/0x380
 [<ffffffff81233535>] ? ext4_mb_new_blocks+0x205/0x8e0
 [<ffffffff8116ed5c>] ? kmem_cache_alloc+0xfc/0x180
 [<ffffffff812335b0>] ext4_mb_new_blocks+0x280/0x8e0
 [<ffffffff8116f2c4>] ? __kmalloc+0x144/0x1c0
 [<ffffffff81221797>] ? ext4_find_extent+0x97/0x320
 [<ffffffff812257f4>] ext4_ext_map_blocks+0xbc4/0x1050
 [<ffffffff811fa387>] ? ext4_map_blocks+0x297/0x430
 [<ffffffff811fa3ab>] ext4_map_blocks+0x2bb/0x430
 [<ffffffff81200e43>] ? ext4_init_io_end+0x23/0x50
 [<ffffffff811feb44>] ext4_writepages+0x564/0xaf0
 [<ffffffff815cde3b>] ? _raw_spin_unlock+0x2b/0x40
 [<ffffffff810ac7bd>] ? lock_release_non_nested+0x2fd/0x3c0
 [<ffffffff811a009e>] ? writeback_sb_inodes+0x10e/0x490
 [<ffffffff811a009e>] ? writeback_sb_inodes+0x10e/0x490
 [<ffffffff811377e3>] do_writepages+0x23/0x40
 [<ffffffff8119c8ce>] __writeback_single_inode+0x9e/0x280
 [<ffffffff811a026b>] writeback_sb_inodes+0x2db/0x490
 [<ffffffff811a0664>] wb_writeback+0x174/0x2d0
 [<ffffffff810ac359>] ? lock_release_holdtime+0x29/0x190
 [<ffffffff811a0863>] wb_do_writeback+0xa3/0x200
 [<ffffffff811a0a40>] bdi_writeback_workfn+0x80/0x230
 [<ffffffff81085618>] ? process_one_work+0x228/0x4d0
 [<ffffffff810856cd>] process_one_work+0x2dd/0x4d0
 [<ffffffff81085618>] ? process_one_work+0x228/0x4d0
 [<ffffffff81085c1d>] worker_thread+0x35d/0x460
 [<ffffffff810858c0>] ? process_one_work+0x4d0/0x4d0
 [<ffffffff810858c0>] ? process_one_work+0x4d0/0x4d0
 [<ffffffff8108a885>] kthread+0xf5/0x100
 [<ffffffff810990e5>] ? local_clock+0x25/0x30
 [<ffffffff8108a790>] ? __init_kthread_worker+0x70/0x70
 [<ffffffff815ce2ac>] ret_from_fork+0x7c/0xb0
 [<ffffffff8108a790>] ? __init_kthread_work
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

Besides the fact that this replacement improves code readability
it also protects from errors caused direct EXT4_S(sb)->s_es manipulation
which may result attempt to use uninitialized  csum machinery.

#Testcase_BEGIN
IMG=/dev/ram0
MNT=/mnt
mkfs.ext4 $IMG
mount $IMG $MNT
#Enable feature directly on disk, on mounted fs
tune2fs -O metadata_csum  $IMG
# Provoke metadata update, likey result in OOPS
touch $MNT/test
umount $MNT
#Testcase_END

# Replacement script
@@
expression E;
@@
- EXT4_HAS_RO_COMPAT_FEATURE(E, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
+ ext4_has_metadata_csum(E)

https://bugzilla.kernel.org/show_bug.cgi?id=82201Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

In patch 'ext4: refactor ext4_move_extents code base',  Dmitry Monakhov has
refactored ext4_move_extents' implementation, but forgot to update the
corresponding comments, this patch will try to delete some useless comments.
Reviewed-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NXiaoguang Wang <wangxg.fnst@cn.fujitsu.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Delalloc write journal reservations only reserve 1 credit,
to update the inode if necessary.  However, it may happen
once in a filesystem's lifetime that a file will cross
the 2G threshold, and require the LARGE_FILE feature to
be set in the superblock as well, if it was not set already.

This overruns the transaction reservation, and can be
demonstrated simply on any ext4 filesystem without the LARGE_FILE
feature already set:

dd if=/dev/zero of=testfile bs=1 seek=2147483646 count=1 \
	conv=notrunc of=testfile
sync
dd if=/dev/zero of=testfile bs=1 seek=2147483647 count=1 \
	conv=notrunc of=testfile

leads to:

EXT4-fs: ext4_do_update_inode:4296: aborting transaction: error 28 in __ext4_handle_dirty_super
EXT4-fs error (device loop0) in ext4_do_update_inode:4301: error 28
EXT4-fs error (device loop0) in ext4_reserve_inode_write:4757: Readonly filesystem
EXT4-fs error (device loop0) in ext4_dirty_inode:4876: error 28
EXT4-fs error (device loop0) in ext4_da_write_end:2685: error 28

Adjust the number of credits based on whether the flag is
already set, and whether the current write may extend past the
LARGE_FILE limit.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NAndreas Dilger <adilger@dilger.ca>
Cc: stable@vger.kernel.org

If there is a corrupted file system which has directory entries that
point at reserved, metadata inodes, prohibit them from being used by
treating them the same way we treat Boot Loader inodes --- that is,
mark them to be bad inodes.  This prohibits them from being opened,
deleted, or modified via chmod, chown, utimes, etc.

In particular, this prevents a corrupted file system which has a
directory entry which points at the journal inode from being deleted
and its blocks released, after which point Much Hilarity Ensues.
Reported-by: NSami Liedes <sami.liedes@iki.fi>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

The boot loader inode (inode #5) should never be visible in the
directory hierarchy, but it's possible if the file system is corrupted
that there will be a directory entry that points at inode #5.  In
order to avoid accidentally trashing it, when such a directory inode
is opened, the inode will be marked as a bad inode, so that it's not
possible to modify (or read) the inode from userspace.

Unfortunately, when we unlink this (invalid/illegal) directory entry,
we will put the bad inode on the ophan list, and then when try to
unlink the directory, we don't actually remove the bad inode from the
orphan list before freeing in-memory inode structure.  This means the
in-memory orphan list is corrupted, leading to a kernel oops.

In addition, avoid truncating a bad inode in ext4_destroy_inode(),
since truncating the boot loader inode is not a smart thing to do.
Reported-by: NSami Liedes <sami.liedes@iki.fi>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

Otherwise this provokes complain like follows:
WARNING: CPU: 12 PID: 5795 at fs/ext4/ext4_jbd2.c:48 ext4_journal_check_start+0x4e/0xa0()
Modules linked in: brd iTCO_wdt lpc_ich mfd_core igb ptp dm_mirror dm_region_hash dm_log dm_mod
CPU: 12 PID: 5795 Comm: python Not tainted 3.17.0-rc2-00175-gae5344f #158
Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011
 0000000000000030 ffff8808116cfd28 ffffffff815c7dfc 0000000000000030
 0000000000000000 ffff8808116cfd68 ffffffff8106ce8c ffff8808116cfdc8
 ffff880813b16000 ffff880806ad6ae8 ffffffff81202008 0000000000000000
Call Trace:
 [<ffffffff815c7dfc>] dump_stack+0x51/0x6d
 [<ffffffff8106ce8c>] warn_slowpath_common+0x8c/0xc0
 [<ffffffff81202008>] ? ext4_ioctl+0x9e8/0xeb0
 [<ffffffff8106ceda>] warn_slowpath_null+0x1a/0x20
 [<ffffffff8122867e>] ext4_journal_check_start+0x4e/0xa0
 [<ffffffff81228c10>] __ext4_journal_start_sb+0x90/0x110
 [<ffffffff81202008>] ext4_ioctl+0x9e8/0xeb0
 [<ffffffff8107b0bd>] ? ptrace_stop+0x24d/0x2f0
 [<ffffffff81088530>] ? alloc_pid+0x480/0x480
 [<ffffffff8107b1f2>] ? ptrace_do_notify+0x92/0xb0
 [<ffffffff81186545>] do_vfs_ioctl+0x4e5/0x550
 [<ffffffff815cdbcb>] ? _raw_spin_unlock_irq+0x2b/0x40
 [<ffffffff81186603>] SyS_ioctl+0x53/0x80
 [<ffffffff815ce2ce>] tracesys+0xd0/0xd5
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

It is reasonable to prepend newly created index to older one.

[ Dropped no longer used function parameter newext. -tytso ]
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

When ext4_do_update_inode() gets error from ext4_inode_blocks_set(),
error number should be returned.
Signed-off-by: NLi Xi <lixi@ddn.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NJan Kara <jack@suse.cz>

Use truncate_isize_extended() when hole is being created in a file so that
->page_mkwrite() will get called for the partial tail page if it is
mmaped (see the first patch in the series for details).
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

->page_mkwrite() is used by filesystems to allocate blocks under a page
which is becoming writeably mmapped in some process' address space. This
allows a filesystem to return a page fault if there is not enough space
available, user exceeds quota or similar problem happens, rather than
silently discarding data later when writepage is called.

However VFS fails to call ->page_mkwrite() in all the cases where
filesystems need it when blocksize < pagesize. For example when
blocksize = 1024, pagesize = 4096 the following is problematic:
  ftruncate(fd, 0);
  pwrite(fd, buf, 1024, 0);
  map = mmap(NULL, 1024, PROT_WRITE, MAP_SHARED, fd, 0);
  map[0] = 'a';       ----> page_mkwrite() for index 0 is called
  ftruncate(fd, 10000); /* or even pwrite(fd, buf, 1, 10000) */
  mremap(map, 1024, 10000, 0);
  map[4095] = 'a';    ----> no page_mkwrite() called

At the moment ->page_mkwrite() is called, filesystem can allocate only
one block for the page because i_size == 1024. Otherwise it would create
blocks beyond i_size which is generally undesirable. But later at
->writepage() time, we also need to store data at offset 4095 but we
don't have block allocated for it.

This patch introduces a helper function filesystems can use to have
->page_mkwrite() called at all the necessary moments.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

There's no longer any need to have a separate set of super_operations
for nojournal mode.
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Through an oversight, when we added nojournal support to ext4, we
didn't add support to allow file system freezing.  This is relatively
easy to add, so let's do it.
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reported-by: NDexuan Cui <decui@microsoft.com>

This allows us to eliminate duplicate code, and eventually allow us to
also fold ext4_sops and ext4_nojournal_sops together.
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

The check whether quota format is set even though there are no
quota files with journalled quota is pointless and it actually
makes it impossible to turn off journalled quotas (as there's
no way to unset journalled quota format). Just remove the check.

CC: stable@vger.kernel.org
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

__jbd2_journal_clean_checkpoint_list() returns number of buffers it
freed but noone was using the value so just stop doing that. This
also allows for simplifying the calling convention for
journal_clean_once_cp_list().
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Yuanhan has reported that when he is running fsync(2) heavy workload
creating new files over ramdisk, significant amount of time is spent in
__jbd2_journal_clean_checkpoint_list() trying to clean old transactions
(but they cannot be cleaned up because flusher hasn't yet checkpointed
those buffers). The workload can be generated by:
  fs_mark -d /fs/ram0/1 -D 2 -N 2560 -n 1000000 -L 1 -S 1 -s 4096

Reduce the amount of scanning by stopping to scan the transaction list
once we find a transaction that cannot be checkpointed. Note that this
way of cleaning is still enough to keep freeing space in the journal
after fully checkpointed transactions.
Reported-and-tested-by: NYuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Production fs likely compiled/mounted w/o jbd debugging, so orphan
list clearing will be silent.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

If EIO happens after we have dropped j_state_lock, we won't notice
that the journal has been aborted.  So it is reasonable to move this
check after we have grabbed the j_checkpoint_mutex and re-grabbed the
j_state_lock.  This patch helps to prevent false positive complain
after EIO.

#DMESG:
__jbd2_log_wait_for_space: needed 8448 blocks and only had 8386 space available
__jbd2_log_wait_for_space: no way to get more journal space in ram1-8
------------[ cut here ]------------
WARNING: CPU: 15 PID: 6739 at fs/jbd2/checkpoint.c:168 __jbd2_log_wait_for_space+0x188/0x200()
Modules linked in: brd iTCO_wdt lpc_ich mfd_core igb ptp dm_mirror dm_region_hash dm_log dm_mod
CPU: 15 PID: 6739 Comm: fsstress Tainted: G        W      3.17.0-rc2-00429-g684de574 #139
Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011
 00000000000000a8 ffff88077aaab878 ffffffff815c1a8c 00000000000000a8
 0000000000000000 ffff88077aaab8b8 ffffffff8106ce8c ffff88077aaab898
 ffff8807c57e6000 ffff8807c57e6028 0000000000002100 ffff8807c57e62f0
Call Trace:
 [<ffffffff815c1a8c>] dump_stack+0x51/0x6d
 [<ffffffff8106ce8c>] warn_slowpath_common+0x8c/0xc0
 [<ffffffff8106ceda>] warn_slowpath_null+0x1a/0x20
 [<ffffffff812419f8>] __jbd2_log_wait_for_space+0x188/0x200
 [<ffffffff8123be9a>] start_this_handle+0x4da/0x7b0
 [<ffffffff810990e5>] ? local_clock+0x25/0x30
 [<ffffffff810aba87>] ? lockdep_init_map+0xe7/0x180
 [<ffffffff8123c5bc>] jbd2__journal_start+0xdc/0x1d0
 [<ffffffff811f2414>] ? __ext4_new_inode+0x7f4/0x1330
 [<ffffffff81222a38>] __ext4_journal_start_sb+0xf8/0x110
 [<ffffffff811f2414>] __ext4_new_inode+0x7f4/0x1330
 [<ffffffff810ac359>] ? lock_release_holdtime+0x29/0x190
 [<ffffffff812025bb>] ext4_create+0x8b/0x150
 [<ffffffff8117fe3b>] vfs_create+0x7b/0xb0
 [<ffffffff8118097b>] do_last+0x7db/0xcf0
 [<ffffffff8117e31d>] ? inode_permission+0x4d/0x50
 [<ffffffff811845d2>] path_openat+0x242/0x590
 [<ffffffff81191a76>] ? __alloc_fd+0x36/0x140
 [<ffffffff81184a6a>] do_filp_open+0x4a/0xb0
 [<ffffffff81191b61>] ? __alloc_fd+0x121/0x140
 [<ffffffff81172f20>] do_sys_open+0x170/0x220
 [<ffffffff8117300e>] SyS_open+0x1e/0x20
 [<ffffffff811715d6>] SyS_creat+0x16/0x20
 [<ffffffff815c7e12>] system_call_fastpath+0x16/0x1b
---[ end trace cd71c831f82059db ]---
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Free the buffer head if the journal descriptor block fails checksum
verification.

This is the jbd2 port of the e2fsprogs patch "e2fsck: free bh on csum
verify error in do_one_pass".
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Cc: stable@vger.kernel.org

When loading extended attributes, check each entry's value offset to
make sure it doesn't collide with the entries.

Without this check it is easy to crash the kernel by mounting a
malicious FS containing a file with an EA wherein e_value_offs = 0 and
e_value_size > 0 and then deleting the EA, which corrupts the name
list.

(See the f_ea_value_crash test's FS image in e2fsprogs for an example.)
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

If inline->extent conversion fails (most probably due to ENOSPC) and
we release the temporary page that we allocated to transfer the file
contents, don't keep using the page pointer after releasing the page.
This occasionally leads to complaints about evicting locked pages or
hangs when blocksize > pagesize, because it's possible for the page to
get reallocated elsewhere in the meantime.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Tao Ma <tm@tao.ma>

If the external journal device has metadata_csum enabled, verify
that the superblock checksum matches the block before we try to
mount.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Clear all three journal checksum feature flags before turning on
whichever journal checksum options we want.  Rearrange the error
checking so that newer flags get complained about first.
Reported-by: NTR Reardon <thomas_reardon@hotmail.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Currently sysfs feature files uses ext4_attr_ops as the file operations
to show/store data. However the feature files is not supposed to contain
any data at all, the sole existence of the file means that the module
support the feature. Moreover, none of the sysfs feature attributes
actually register show/store functions so that would not be a problem.

However if a sysfs feature attribute register a show or store function
we might be in trouble because the kobject in this case is _not_ embedded
in the ext4_sb_info structure as ext4_attr_show/store expect.

So just to be safe, provide separate empty sysfs_ops to use in
ext4_feat_ktype. This might safe us from potential problems in the
future. As a bonus we can "store" something more descriptive than
nothing in the files, so let it contain "enabled" to make it clear that
the feature is really present in the module.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Currently there is no easy way to tell that the mounted file system
contains errors other than checking for log messages, or reading the
information directly from superblock.

This patch adds new sysfs entries:

errors_count		(number of fs errors we encounter)
first_error_time	(unix timestamp for the first error we see)
last_error_time		(unix timestamp for the last error we see)

If the file system is not marked as containing errors then any of the
file will return 0. Otherwise it will contain valid information. More
details about the errors should as always be found in the logs.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

MAXQUOTAS value defines maximum number of quota types VFS supports.
This isn't necessarily the number of types ext4 supports. Although
ext4 will support project quotas, use ext4 private definition for
consistency with other filesystems.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Sicne the jbd/jbd2 superblock is not released until the file system is
unmounted, allocate the buffer cache from the non-moveable area to
allow page migration and CMA allocations to more easily succeed.
Signed-off-by: NGioh Kim <gioh.kim@lge.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

Since the ext4 superblock is not released until the file system is
unmounted, allocate the buffer cache entry for the ext4 superblock out
of the non-moveable are to allow page migrations and thus CMA
allocations to more easily succeed if the CMA area is limited.
Signed-off-by: NGioh Kim <gioh.kim@lge.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

A buffer cache is allocated from movable area because it is referred
for a while and released soon.  But some filesystems are taking buffer
cache for a long time and it can disturb page migration.

New APIs are introduced to allocate buffer cache with user specific
flag.  *_gfp APIs are for user want to set page allocation flag for
page cache allocation.  And *_unmovable APIs are for the user wants to
allocate page cache from non-movable area.
Signed-off-by: NGioh Kim <gioh.kim@lge.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

Suggested-by: NAndreas Dilger <adilger@dilger.ca>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

When we discover written out buffer in transaction checkpoint list we
don't have to recheck validity of a transaction. Either this is the
last buffer in a transaction - and then we are done - or this isn't
and then we can just take another buffer from the checkpoint list
without dropping j_list_lock.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

The __jbd2_journal_remove_checkpoint() doesn't require an elevated
b_count; indeed, until the jh structure gets released by the call to
jbd2_journal_put_journal_head(), the bh's b_count is elevated by
virtue of the existence of the jh structure.
Suggested-by: NJan Kara <jack@suse.cz>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Having done a full regression test, we can now drop the
DELALLOC_RESERVED state flag.
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

The EXT4_STATE_DELALLOC_RESERVED flag was originally implemented
because it was too hard to make sure the mballoc and get_block flags
could be reliably passed down through all of the codepaths that end up
calling ext4_mb_new_blocks().

Since then, we have mb_flags passed down through most of the code
paths, so getting rid of EXT4_STATE_DELALLOC_RESERVED isn't as tricky
as it used to.

This commit plumbs in the last of what is required, and then adds a
WARN_ON check to make sure we haven't missed anything.  If this passes
a full regression test run, we can then drop
EXT4_STATE_DELALLOC_RESERVED.
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

Instead of initializing the allocation_request structure in
ext4_alloc_branch(), set it up in ext4_ind_map_blocks(), and then pass
it to ext4_alloc_branch() and ext4_splice_branch().

This allows ext4_ind_map_blocks to pass flags in the allocation
request structure without having to add Yet Another argument to
ext4_alloc_branch().
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

This commit adds some statictics in extent status tree shrinker.  The
purpose to add these is that we want to collect more details when we
encounter a stall caused by extent status tree shrinker.  Here we count
the following statictics:
  stats:
    the number of all objects on all extent status trees
    the number of reclaimable objects on lru list
    cache hits/misses
    the last sorted interval
    the number of inodes on lru list
  average:
    scan time for shrinking some objects
    the number of shrunk objects
  maximum:
    the inode that has max nr. of objects on lru list
    the maximum scan time for shrinking some objects

The output looks like below:
  $ cat /proc/fs/ext4/sda1/es_shrinker_info
  stats:
    28228 objects
    6341 reclaimable objects
    5281/631 cache hits/misses
    586 ms last sorted interval
    250 inodes on lru list
  average:
    153 us scan time
    128 shrunk objects
  maximum:
    255 inode (255 objects, 198 reclaimable)
    125723 us max scan time

If the lru list has never been sorted, the following line will not be
printed:
    586ms last sorted interval
If there is an empty lru list, the following lines also will not be
printed:
    250 inodes on lru list
  ...
  maximum:
    255 inode (255 objects, 198 reclaimable)
    0 us max scan time

Meanwhile in this commit a new trace point is defined to print some
details in __ext4_es_shrink().

Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NZheng Liu <wenqing.lz@taobao.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>