f2fs_sync_file()             remount_ro
 - f2fs_readonly
                               - destroy_flush_cmd_control
 - f2fs_issue_flush
   - no fcc pointer!

So, this patch doesn't free fcc in this case, but just stop its kernel thread
which sends flush commands.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This fixes missing freeing meta pages in the error case.
Tested-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Previous mkfs.f2fs allows small partition inappropriately, so f2fs should detect
that as well.

Refer this in f2fs-tools.

mkfs.f2fs: detect small partition by overprovision ratio and # of segments
Reported-and-Tested-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The sync_fs in f2fs_balance_fs_bg must avoid interrupting current user requests.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This reverts commit 1beba1b3.

The perpcu_counter doesn't provide atomicity in single core and consume more
DRAM. That incurs fs_mark test failure due to ENOMEM.

Cc: stable@vger.kernel.org # 4.7+
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

We should use AOP_WRITEPAGE_ACTIVATE when we bypass writing pages.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If a file needs to keep its i_size by fallocate, we need to turn off auto
recovery during roll-forward recovery.

This will resolve the below scenario.

1. xfs_io -f /mnt/f2fs/file -c "pwrite 0 4096" -c "fsync"
2. xfs_io -f /mnt/f2fs/file -c "falloc -k 4096 4096" -c "fsync"
3. md5sum /mnt/f2fs/file;
4. godown /mnt/f2fs/
5. umount /mnt/f2fs/
6. mount -t f2fs /dev/sdx /mnt/f2fs
7. md5sum /mnt/f2fs/file
Reported-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

We don't guarantee cp_addr is fixed by cp_version.
This is to sync with f2fs-tools.

Cc: stable@vger.kernel.org
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The addition of multiple-device support broke CONFIG_BLK_DEV_ZONED
on 32-bit machines because of a 64-bit division:

fs/f2fs/f2fs.o: In function `__issue_discard_async':
extent_cache.c:(.text.__issue_discard_async+0xd4): undefined reference to `__aeabi_uldivmod'

Fortunately, bdev_zone_size() is guaranteed to return a power-of-two
number, so we can replace the % operator with a cheaper bit mask.

Fixes: 792b84b74b54 ("f2fs: support multiple devices")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The struct file_operations instance serving the f2fs/status debugfs file
lacks an initialization of its ->owner.

This means that although that file might have been opened, the f2fs module
can still get removed. Any further operation on that opened file, releasing
included,  will cause accesses to unmapped memory.

Indeed, Mike Marshall reported the following:

  BUG: unable to handle kernel paging request at ffffffffa0307430
  IP: [<ffffffff8132a224>] full_proxy_release+0x24/0x90
  <...>
  Call Trace:
   [] __fput+0xdf/0x1d0
   [] ____fput+0xe/0x10
   [] task_work_run+0x8e/0xc0
   [] do_exit+0x2ae/0xae0
   [] ? __audit_syscall_entry+0xae/0x100
   [] ? syscall_trace_enter+0x1ca/0x310
   [] do_group_exit+0x44/0xc0
   [] SyS_exit_group+0x14/0x20
   [] do_syscall_64+0x61/0x150
   [] entry_SYSCALL64_slow_path+0x25/0x25
  <...>
  ---[ end trace f22ae883fa3ea6b8 ]---
  Fixing recursive fault but reboot is needed!

Fix this by initializing the f2fs/status file_operations' ->owner with
THIS_MODULE.

This will allow debugfs to grab a reference to the f2fs module upon any
open on that file, thus preventing it from getting removed.

Fixes: 902829aa ("f2fs: move proc files to debugfs")
Reported-by: Mike Marshall <hubcap@omnibond.com>
Reported-by: Martin Brandenburg <martin@omnibond.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

While calculating inode count that we can create at most in the left space,
we should consider space which data/node blocks occupied, since we create
data/node mixly in main area. So fix the wrong calculation in ->statfs.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Drop duplicate header timer.h from segment.c.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If i_size is not aligned to the f2fs's block size, we should not skip inode
update during fsync.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If i_size is already valid during roll_forward recovery, we should not update
it according to the block alignment.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

For below two cases, we can't guarantee data consistence:

a)
1. xfs_io "pwrite 0 4195328" "fsync"
2. xfs_io "pwrite 4195328 1024" "fdatasync"
3. godown
4. umount & mount
--> isize we updated before fdatasync won't be recovered

b)
1. xfs_io "pwrite -S 0xcc 0 4202496" "fsync"
2. xfs_io "fpunch 4194304 4096" "fdatasync"
3. godown
4. umount & mount
--> dnode we punched before fdatasync won't be recovered

The reason is that normally fdatasync won't be aware of modification
of metadata in file, e.g. isize changing, dnode updating, so in ->fsync
we will skip flushing node pages for above cases, result in making
fdatasynced file being lost during recovery.

Currently we have introduced DIRTY_META global list in sbi for tracking
dirty inode selectively, so in fdatasync we can choose to flush nodes
depend on dirty state of current inode in the list.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Thread A		Thread B		Thread C
- f2fs_create
 - f2fs_new_inode
  - f2fs_lock_op
   - alloc_nid
    alloc last nid
  - f2fs_unlock_op
			- f2fs_create
			 - f2fs_new_inode
			  - f2fs_lock_op
			   - alloc_nid
			    as node count still not
			    be increased, we will
			    loop in alloc_nid
						- f2fs_write_node_pages
						 - f2fs_balance_fs_bg
						  - f2fs_sync_fs
						   - write_checkpoint
						    - block_operations
						     - f2fs_lock_all
 - f2fs_lock_op

While creating new inode, we do not allocate and account nid atomically,
so that when there is almost no free nids left, we may encounter deadloop
like above stack.

In order to avoid that, reuse nm_i::available_nids for accounting free nids
and make nid allocation and counting being atomical during node creation.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Thread A			Thread B

- write_checkpoint
 - block_operations
   -blk_start_plug
    -sync_node_pages		- f2fs_do_sync_file
				 - fsync_node_pages
				  - f2fs_wait_on_page_writeback

Thread A wait for global F2FS_DIRTY_NODES decreased to zero,
it start a plug list, some requests have been added to this list.
Thread B lock one dirty node page, and wait this page write back.
But this page has been in plug list of thread A with PG_writeback flag.
Thread A keep on running and its plug list has no chance to finish,
so it seems a deadlock between cp and fsync path.

This patch add a wait on page write back before set node page dirty
to avoid this problem.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Pengyang Hou <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Normally, while committing checkpoint, we will wait on all pages to be
writebacked no matter the page is data or metadata, so in scenario where
there are lots of data IO being submitted with metadata, we may suffer
long latency for waiting writeback during checkpoint.

Indeed, we only care about persistence for pages with metadata, but not
pages with data, as file system consistent are only related to metadate,
so in order to avoid encountering long latency in above scenario, let's
recognize and reference metadata in submitted IOs, wait writeback only
for metadatas.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Previously, written_valid_blocks was got by ckpt->valid_block_count. But if
the last checkpoint has some NEW_ADDR due to power-cut, we can get wrong value.
Fix it to get the number from actual written block count from sit entries.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If many threads hit has_not_enough_free_secs() in f2fs_balance_fs() at the same
time, all the threads would do FG_GC or BG_GC.
In this critical path, we totally don't need to do BG_GC at all.
Let's avoid that.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

In direct_IO path of f2fs_file_write_iter(),
1. f2fs_preallocate_blocks(F2FS_GET_BLOCK_PRE_DIO)
   -> allocate LBA X
2. f2fs_direct_IO()
   -> return 0;

Then,
f2fs_write_data_page() will allocate another LBA X+1.

This makes EIO triggered by HM-SMR.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch has no functional change.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch implements multiple devices support for f2fs.
Given multiple devices by mkfs.f2fs, f2fs shows them entirely as one big
volume under one f2fs instance.

Internal block management is very simple, but we will modify block allocation
and background GC policy to boost IO speed by exploiting them accoording to
each device speed.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

We can allow dio reads for LFS mode, while doing buffered writes for dio writes.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Now we don't need to be too much careful about storage alignment for dio, since
its speed becomes quite fast and we'd better avoid any misalignment first.

Revert: 38aa0889 (f2fs: align direct_io'ed data to section)
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If one block has been to written to a new place, just return
in move data process. This patch check it again with holding
page lock.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

i_times of inode will be set with current system time which can be
configured through 'date', so it's not safe to judge dnode block as
garbage data or unchanged inode depend on i_times.

Now, we have used enhanced 'cp_ver + cp' crc method to verify valid
dnode block, so I expect recoverying invalid dnode is almost not
possible.

This reverts commit 807b1e1c.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The generic freeze_super() calls sync_filesystems() before f2fs_freeze().
So, basically we don't need to do checkpoint in f2fs_freeze(). But, in xfs/068,
it triggers circular locking problem below due to gc_mutex for checkpoint.

======================================================
[ INFO: possible circular locking dependency detected ]
4.9.0-rc1+ #132 Tainted: G           OE
-------------------------------------------------------

1. wait for __sb_start_write() by

 [<ffffffff9845f353>] dump_stack+0x85/0xc2
 [<ffffffff980e80bf>] print_circular_bug+0x1cf/0x230
 [<ffffffff980eb4d0>] __lock_acquire+0x19e0/0x1bc0
 [<ffffffff980ebdcb>] lock_acquire+0x11b/0x220
 [<ffffffffc08c7c3b>] ? f2fs_drop_inode+0x9b/0x160 [f2fs]
 [<ffffffff9826bdd0>] __sb_start_write+0x130/0x200
 [<ffffffffc08c7c3b>] ? f2fs_drop_inode+0x9b/0x160 [f2fs]
 [<ffffffffc08c7c3b>] f2fs_drop_inode+0x9b/0x160 [f2fs]
 [<ffffffff98289991>] iput+0x171/0x2c0
 [<ffffffffc08cfccf>] f2fs_sync_inode_meta+0x3f/0xf0 [f2fs]
 [<ffffffffc08cfe04>] block_operations+0x84/0x110 [f2fs]
 [<ffffffffc08cff78>] write_checkpoint+0xe8/0xf20 [f2fs]
 [<ffffffff980e979d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffffc08c6de9>] ? f2fs_sync_fs+0x79/0x190 [f2fs]
 [<ffffffff9803e9d9>] ? sched_clock+0x9/0x10
 [<ffffffffc08c6de9>] ? f2fs_sync_fs+0x79/0x190 [f2fs]
 [<ffffffffc08c6df5>] f2fs_sync_fs+0x85/0x190 [f2fs]
 [<ffffffff982a4f90>] ? do_fsync+0x70/0x70
 [<ffffffff982a4f90>] ? do_fsync+0x70/0x70
 [<ffffffff982a4fb0>] sync_fs_one_sb+0x20/0x30
 [<ffffffff9826ca3e>] iterate_supers+0xae/0x100
 [<ffffffff982a50b5>] sys_sync+0x55/0x90
 [<ffffffff9890b345>] entry_SYSCALL_64_fastpath+0x23/0xc6

2. wait for sbi->gc_mutex by

 [<ffffffff980ebdcb>] lock_acquire+0x11b/0x220
 [<ffffffff989063d6>] mutex_lock_nested+0x76/0x3f0
 [<ffffffffc08c6de9>] f2fs_sync_fs+0x79/0x190 [f2fs]
 [<ffffffffc08c7a6c>] f2fs_freeze+0x1c/0x20 [f2fs]
 [<ffffffff9826b6ef>] freeze_super+0xcf/0x190
 [<ffffffff9827eebc>] do_vfs_ioctl+0x53c/0x6a0
 [<ffffffff9827f099>] SyS_ioctl+0x79/0x90
 [<ffffffff9890b345>] entry_SYSCALL_64_fastpath+0x23/0xc6
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Previously, we assigned CURSEG_WARM_DATA for direct_io, but if we have two or
four logs, we do not use that type at all.
Let's fix it.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Shouldn't update in-memory i_atime with on-disk i_mtime of inode when
recovering inode.

Shuoran found this bug which is hidden for a long time, honour is belong
to him.
Signed-off-by: Shuoran Liu <liushuoran@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

We should record updating status of inode only for living inode, for those
unlinked inode it needs to clear its ino cache, otherwise after the ino
was been reused, it will cause unneeded node page writing during ->fsync.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Similarly to the regular discard, trace zone reset events.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

When a zoned block device is mounted, discarding sections
contained in sequential zones must reset the zone write pointer.
For sections contained in conventional zones, the regular discard
is used if the drive supports it.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

With the zoned block device feature enabled, section discard
need to do a zone reset for sections contained in sequential
zones, and a regular discard (if supported) for sections
stored in conventional zones. Avoid the need for a costly
report zones to obtain a section zone type when discarding it
by caching the types of the device zones in the super block
information. This cache is initialized at mount time for mounts
with the zoned block device feature enabled.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The LFS mode is mandatory for host-managed zoned block devices as
update in place optimizations are not possible for segments in
sequential zones.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Zone write pointer reset acts as discard for zoned block
devices. So if the zoned block device feature is enabled,
always declare that discard is enabled, even if the device
does not actually support the command.
For the same reason, prevent the use the "nodicard" mount
option.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

For zoned block devices, discard is replaced by zone reset. So
do not warn if the device does not supports discard.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The F2FS_FEATURE_BLKZONED feature indicates that the drive was formatted
 with zone alignment optimization. This is optional for host-aware
devices, but mandatory for host-managed zoned block devices.
So check that the feature is set in this latter case.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

SMR stands for "Shingled Magnetic Recording" which makes sense
only for hard disk drives (spinning rust). The ZBC/ZAC standards
enable management of SMR disks, but solid state drives may also
support those standards. So rename the HMSMR feature to BLKZONED
to avoid a HDD centric terminology. For the same reason, rename
f2fs_sb_mounted_hmsmr to f2fs_sb_mounted_blkzoned.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>