This patch adds a tracepoint for f2fs_direct_IO.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We do not need to block on ->node_write among different node page writers e.g.
fsync/flush, unless we have a node page writer from write_checkpoint.
So it's better use rw_semaphore instead of mutex type for ->node_write to
promote performance.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fixes wrong coding style.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

There are redundant lines in allocate_data_block.

In this function, we call refresh_sit_entry with old seg and old curseg.
After that, we call locate_dirty_segment with old curseg.

But, the new address is always allocated from old curseg and
we call locate_dirty_segment with old curseg in refresh_sit_entry.
So, we do not need to call locate_dirty_segment with old curseg again.

We've discussed like below:

Jaegeuk said:
 "When considering SSR, we need to take care of the following scenario.
  - old segno : X
  - new address : Z
  - old curseg : Y
  This means, a new block is supposed to be written to Z from X.
  And Z is newly allocated in the same path from Y.

  In that case, we should trigger locate_dirty_segment for Y, since
  it was a current_segment and can be dirty owing to SSR.
  But that was not included in the dirty list."

Changman said:
 "We already choosed old curseg(Y) and then we allocate new address(Z) from old
  curseg(Y). After that we call refresh_sit_entry(old address, new address).
  In the funcation, we call locate_dirty_segment with old seg and old curseg.
  So calling locate_dirty_segment after refresh_sit_entry again is redundant."

Jaegeuk said:
 "Right. The new address is always allocated from old_curseg."
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NDongho Sim <dh.sim@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a tracepoint for f2fs_issue_flush.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch eliminates the propagation of recovery errors to the next mount.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If the bit is already set, we don't need to reset it, and vice versa.
Because we don't need to make the caches dirty for that.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fixes the wrongly used unlikely condition.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch enforces in-place-updates only when fdatasync is requested.
If we adopt this in-place-updates for the fdatasync, we can skip to write the
recovery information.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch intends to improve the fsync performance by skipping remaining the
recovery information, only when there is no data that we should recover.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces a inode number list in which represents inodes having
appended data writes or updated data writes after last checkpoint.
This will be used at fsync to determine whether the recovery information
should be written or not.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

For better ino management, this patch replaces the data structure from list
to radix tree.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch changes the naming of orphan-related data structures to use as
inode numbers managed globally.
Later, we can use this facility for managing any inode number lists.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch punches out the core functions to manage the inode numbers.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a mount option, nobarrier, in f2fs.
The assumption in here is that file system keeps the IO ordering, but
doesn't care about cache flushes inside the storages.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We should put root inode correctly in error path of fill_super, otherwise we
may encounter a leak case of inode resource.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Reviewed-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Andrey Tsyvarev reported:
"Using memory error detector reveals the following use-after-free error
in 3.15.0:

AddressSanitizer: heap-use-after-free in f2fs_evict_inode
Read of size 8 by thread T22279:
  [<ffffffffa02d8702>] f2fs_evict_inode+0x102/0x2e0 [f2fs]
  [<ffffffff812359af>] evict+0x15f/0x290
  [<     inlined    >] iput+0x196/0x280 iput_final
  [<ffffffff812369a6>] iput+0x196/0x280
  [<ffffffffa02dc416>] f2fs_put_super+0xd6/0x170 [f2fs]
  [<ffffffff81210095>] generic_shutdown_super+0xc5/0x1b0
  [<ffffffff812105fd>] kill_block_super+0x4d/0xb0
  [<ffffffff81210a86>] deactivate_locked_super+0x66/0x80
  [<ffffffff81211c98>] deactivate_super+0x68/0x80
  [<ffffffff8123cc88>] mntput_no_expire+0x198/0x250
  [<     inlined    >] SyS_umount+0xe9/0x1a0 SYSC_umount
  [<ffffffff8123f1c9>] SyS_umount+0xe9/0x1a0
  [<ffffffff81cc8df9>] system_call_fastpath+0x16/0x1b

Freed by thread T3:
  [<ffffffffa02dc337>] f2fs_i_callback+0x27/0x30 [f2fs]
  [<     inlined    >] rcu_process_callbacks+0x2d6/0x930 __rcu_reclaim
  [<     inlined    >] rcu_process_callbacks+0x2d6/0x930 rcu_do_batch
  [<     inlined    >] rcu_process_callbacks+0x2d6/0x930 invoke_rcu_callbacks
  [<     inlined    >] rcu_process_callbacks+0x2d6/0x930 __rcu_process_callbacks
  [<ffffffff810fd266>] rcu_process_callbacks+0x2d6/0x930
  [<ffffffff8107cce2>] __do_softirq+0x142/0x380
  [<ffffffff8107cf50>] run_ksoftirqd+0x30/0x50
  [<ffffffff810b2a87>] smpboot_thread_fn+0x197/0x280
  [<ffffffff810a8238>] kthread+0x148/0x160
  [<ffffffff81cc8d4c>] ret_from_fork+0x7c/0xb0

Allocated by thread T22276:
  [<ffffffffa02dc7dd>] f2fs_alloc_inode+0x2d/0x170 [f2fs]
  [<ffffffff81235e2a>] iget_locked+0x10a/0x230
  [<ffffffffa02d7495>] f2fs_iget+0x35/0xa80 [f2fs]
  [<ffffffffa02e2393>] f2fs_fill_super+0xb53/0xff0 [f2fs]
  [<ffffffff81211bce>] mount_bdev+0x1de/0x240
  [<ffffffffa02dbce0>] f2fs_mount+0x10/0x20 [f2fs]
  [<ffffffff81212a85>] mount_fs+0x55/0x220
  [<ffffffff8123c026>] vfs_kern_mount+0x66/0x200
  [<     inlined    >] do_mount+0x2b4/0x1120 do_new_mount
  [<ffffffff812400d4>] do_mount+0x2b4/0x1120
  [<     inlined    >] SyS_mount+0xb2/0x110 SYSC_mount
  [<ffffffff812414a2>] SyS_mount+0xb2/0x110
  [<ffffffff81cc8df9>] system_call_fastpath+0x16/0x1b

The buggy address ffff8800587866c8 is located 48 bytes inside
  of 680-byte region [ffff880058786698, ffff880058786940)

Memory state around the buggy address:
  ffff880058786100: ffffffff ffffffff ffffffff ffffffff
  ffff880058786200: ffffffff ffffffff ffffffrr rrrrrrrr
  ffff880058786300: rrrrrrrr rrffffff ffffffff ffffffff
  ffff880058786400: ffffffff ffffffff ffffffff ffffffff
  ffff880058786500: ffffffff ffffffff ffffffff fffffffr
 >ffff880058786600: rrrrrrrr rrrrrrrr rrrfffff ffffffff
                                                ^
  ffff880058786700: ffffffff ffffffff ffffffff ffffffff
  ffff880058786800: ffffffff ffffffff ffffffff ffffffff
  ffff880058786900: ffffffff rrrrrrrr rrrrrrrr rrrr....
  ffff880058786a00: ........ ........ ........ ........
  ffff880058786b00: ........ ........ ........ ........
Legend:
  f - 8 freed bytes
  r - 8 redzone bytes
  . - 8 allocated bytes
  x=1..7 - x allocated bytes + (8-x) redzone bytes

Investigation shows, that f2fs_evict_inode, when called for
'meta_inode', uses invalidate_mapping_pages() for 'node_inode'.
But 'node_inode' is deleted before 'meta_inode' in f2fs_put_super via
iput().

It seems that in common usage scenario this use-after-free is benign,
because 'node_inode' remains partially valid data even after
kmem_cache_free().
But things may change if, while 'meta_inode' is evicted in one f2fs
filesystem, another (mounted) f2fs filesystem requests inode from cache,
and formely
'node_inode' of the first filesystem is returned."

Nids for both meta_inode and node_inode are reservation, so it's not necessary
for us to invalidate pages which will never be allocated.
To fix this issue, let's skipping needlessly invalidating pages for
{meta,node}_inode in f2fs_evict_inode.
Reported-by: NAndrey Tsyvarev <tsyvarev@ispras.ru>
Tested-by: NAndrey Tsyvarev <tsyvarev@ispras.ru>
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Now new interface ->rename2() is added to VFS, here are related description:
https://lkml.org/lkml/2014/2/7/873
https://lkml.org/lkml/2014/2/7/758

This patch adds function f2fs_rename2() to support ->rename2() including
handling both RENAME_EXCHANGE and RENAME_NOREPLACE flag.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Otherwise, if a large amount of direct IO writes were done, the
segment allocation may be failed because no enough segments are gced.

Changes:

v2: add f2fs_balance_fs into __get_data_block instead of f2fs_direct_IO.
Signed-off-by: NHuang, Ying <ying.huang@intel.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In __set_test_and_free we will check whether all segment are free in one section
When free one segment, in order to set section to free status.
But the searching region of segmap is from start segno to last segno of f2fs,
it's not necessary. So let's just only check all segment bitmap of target
section.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We assume that modification of some special application could result in zeroed
name_len, or it is consciously made by somebody. We will deadloop in
find_in_block when name_len of dir entry is zero.

This patch is added for preventing deadloop in above scenario.

change log from v1:
 o use f2fs_bug_on rather than break out from searching dir entry suggested by
Jaegeuk Kim.

Jaegeuk describe:
"Well, IMO, it would be good to add f2fs_bug_on() here with a specific comment.
In the current phase of f2fs, it is more important to investigate the file
system bugs, rather than workarounds for any corrupted images.
And, definitely it needs to stop the kernel if any corrupted image was mounted,
so that we can figure out where the bugs are occurred."
Suggested-by: NJaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In this patch we use below inner macro and function to clean up codes.
1. ADDRS_PER_PAGE
2. SM_I
3. f2fs_readonly
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

When we fail in ->write_begin()/->direct_IO(), our allocated node block in disk
and page cache are still kept, despite these may not be used again.

This patch introduce f2fs_write_failed() to handle the error case of these two
interfaces, it will truncate page cache and blocks of this file according to
i_size.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

kernel side(xx_init_acl), the acl is get/cloned from the parent dir's,
which is credible. So remove the redundant validation check of acl
here.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In our rename process, region of f2fs_lock_op covered is too big as some of the
code like f2fs_empty_dir/f2fs_find_entry are not needed to protect by this lock.

So in the extreme case like doing checkpoint when we rename old inode to exist
inode in a large directory could cause lower concurrency.

Let's reduce the region of f2fs_lock_op to fix this.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

kcalloc manages count*sizeof overflow.

Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: linux-f2fs-devel@lists.sourceforge.net
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Although building NAT journal in cursum reduce the read/write work for NAT
block, but previous design leave us lower performance when write checkpoint
frequently for these cases:
1. if journal in cursum has already full, it's a bit of waste that we flush all
   nat entries to page for persistence, but not to cache any entries.
2. if journal in cursum is not full, we fill nat entries to journal util
   journal is full, then flush the left dirty entries to disk without merge
   journaled entries, so these journaled entries may be flushed to disk at next
   checkpoint but lost chance to flushed last time.

In this patch we merge dirty entries located in same NAT block to nat entry set,
and linked all set to list, sorted ascending order by entries' count of set.
Later we flush entries in sparse set into journal as many as we can, and then
flush merged entries to disk. In this way we can not only gain in performance,
but also save lifetime of flash device.

In my testing environment, it shows this patch can help to reduce NAT block
writes obviously. In hard disk test case: cost time of fsstress is stablely
reduced by about 5%.

1. virtual machine + hard disk:
fsstress -p 20 -n 200 -l 5
		node num	cp count	nodes/cp
based		4599.6		1803.0		2.551
patched		2714.6		1829.6		1.483

2. virtual machine + 32g micro SD card:
fsstress -p 20 -n 200 -l 1 -w -f chown=0 -f creat=4 -f dwrite=0
-f fdatasync=4 -f fsync=4 -f link=0 -f mkdir=4 -f mknod=4 -f rename=5
-f rmdir=5 -f symlink=0 -f truncate=4 -f unlink=5 -f write=0 -S

		node num	cp count	nodes/cp
based		84.5		43.7		1.933
patched		49.2		40.0		1.23

Our latency of merging op shows not bad when handling extreme case like:
merging a great number of dirty nats:
latency(ns)	dirty nat count
3089219		24922
5129423		27422
4000250		24523

change log from v1:
 o fix wrong logic in add_nat_entry when grab a new nat entry set.
 o swith to create slab cache in create_node_manager_caches.
 o use GFP_ATOMIC instead of GFP_NOFS to avoid potential long latency.

change log from v2:
 o make comment position more appropriate suggested by Jaegeuk Kim.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch cleans up simple unnecessary codes.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds f2fs_do_tmpfile to eliminate the redundant init_inode_metadata
flow.
Throught this, we can provide the consistent lock usage, e.g., fi->i_sem,  and
this will enable better debugging stuffs.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Add function f2fs_tmpfile() to support O_TMPFILE file creation, and modify logic
of init_inode_metadata to enable linkat temp file.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

After we call find_data_page in truncate_partial_data_page, we could not
guarantee this page is updated or not as error may occurred in lower layer.

We'd better check status of the page to avoid this no updated page be
writebacked to device.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We have already set page update in ->write_begin, so we should remove redundant
SetPageUptodate in ->write_end.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Pull f2fs bugfixes from Jaegeuk Kim:
 "This includes a couple of bug fixes found by xfstests.  In addition,
  one critical bug was reported by Brian Chadwick, which is falling into
  the infinite loop in balance_dirty_pages.  And it turned out due to
  the IO merging policy in f2fs, which was newly merged in 3.16.

   - fix normal and recovery path for fallocated regions
   - fix error case mishandling
   - recover renamed fsync inodes correctly
   - fix to get out of infinite loops in balance_dirty_pages
   - fix kernel NULL pointer error"

* tag 'f2fs-fixes-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: avoid to access NULL pointer in issue_flush_thread
  f2fs: check bdi->dirty_exceeded when trying to skip data writes
  f2fs: do checkpoint for the renamed inode
  f2fs: release new entry page correctly in error path of f2fs_rename
  f2fs: fix error path in init_inode_metadata
  f2fs: check lower bound nid value in check_nid_range
  f2fs: remove unused variables in f2fs_sm_info
  f2fs: fix not to allocate unnecessary blocks during fallocate
  f2fs: recover fallocated data and its i_size together
  f2fs: fix to report newly allocate region as extent

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=75861

Denis 2014-05-10 11:28:59 UTC reported:
"F2FS-fs (mmcblk0p28): mounting..
 Unable to handle kernel NULL pointer dereference at virtual address 00000018
 ...
 [<c0a2f678>] (_raw_spin_lock+0x3c/0x70) from [<c03a0330>] (issue_flush_thread+0x50/0x17c)
 [<c03a0330>] (issue_flush_thread+0x50/0x17c) from [<c01b4064>] (kthread+0x98/0xa4)
 [<c01b4064>] (kthread+0x98/0xa4) from [<c0108060>] (kernel_thread_exit+0x0/0x8)"

This patch assign cmd_control_info in sm_info before issue_flush_thread is being
created, so this make sure that issue flush thread will have no chance to access
invalid info in fcc.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Reviewed-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If we don't check the current backing device status, balance_dirty_pages can
fall into infinite pausing routine.

This can be occurred when a lot of directories make a small number of dirty
dentry pages including files.
Reported-by: NBrian Chadwick <brianchad@westnet.com.au>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If an inode is renamed, it should be registered as file_lost_pino to conduct
checkpoint at f2fs_sync_file.
Otherwise, the inode cannot be recovered due to no dent_mark in the following
scenario.

Note that, this scenario is from xfstests/322.

1. create "a"
2. fsync "a"
3. rename "a" to "b"
4. fsync "b"
5. Sudden power-cut

After recovery is done, "b" should be seen.
However, the result shows "a", since the recovery procedure does not enter
recover_dentry due to no dent_mark.

The reason is like below.
- The nid of "a" is checkpointed during #2, f2fs_sync_file.
- The inode page for "b" produced by #3 is written without dent_mark by
sync_node_pages.

So, this patch fixes this bug by assinging file_lost_pino to the "a"'s inode.
If the pino is lost, f2fs_sync_file conducts checkpoint, and then recovers
the latest pino and its dentry information for further recovery.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>