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>

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>

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>

Previous get_block in f2fs didn't report the newly allocated region which has
NEW_ADDR.
For reader, it should not report, but fiemap needs this.
So, this patch introduces two get_block sharing core function.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch links f2fs_fiemap with generic function with get_block.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If data are overwritten through dio, previous f2fs doesn't remain the fsync mark
due to no additional node writes.

Note that this patch should resolve the xfstests:311.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a tracepoint for f2fs_read_data_page to trace when page is
readed by user.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_write_{meta,node,data}_pages to trace when
pages are fsyncing/flushing.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_write_{meta,node,data}_page to trace when
page is writting out.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_write_end to trace write op of user.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_write_begin to trace write op of user.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch reduces the lock granularity during write_begin.
When the system is under memory pressure, it would be better to reduce
the locking time for the data pages.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

We don't need to wait on page writeback for these cases.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Introduce help macro ADDRS_PER_PAGE() to get the number of address pointers in
direct node or inode.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If f2fs_write_data_page is called through the reclaim path, we should submit
the bio right away.

This patch resolves the following issue that Marc Dietrich reported.
"It took me a while to bisect a problem which causes my ARM (tegra2) netbook to
frequently stall for 5-10 seconds when I enable EXA acceleration (opentegra
experimental ddx)."
And this patch fixes that.
Reported-by: NMarc Dietrich <marvin24@gmx.de>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

We'd better handle inline data case independently in f2fs_bmap().
It can reduce our handling time in f2fs_bmap().
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If so many dirty dentry blocks are cached, not reached to the flush condition,
we should fall into livelock in balance_dirty_pages.
So, let's consider the mem size for the condition.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch replace some general codes with redirty_page_for_writepage, which
can be enabled after consideration on additional procedure like counting dirty
pages appropriately.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

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

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

unmodified, for now
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We should unlock page in ->readpage() path and also should unlock & release page
in error path of ->write_begin() to avoid deadlock or memory leak.
So let's add release code to fix the problem when we fail to read inline data.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduce is_merged_page() to check whether current page is merged
in f2fs bio cache. When page is not in cache, we can avoid submitting bio cache,
resulting in having more chance to merge pages.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduces nr_pages_to_write to align page writes to the segment
or other operational unit size, which can be tuned according to the system
environment.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch increases pages_skipped when skipping writepages.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduces nr_pages_to_skip(sbi, type) to determine writepages can
be skipped.
The dentry, node, and meta pages can be conrolled by F2FS without breaking the
FS consistency.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

We should de-account dirty counters for page when redirty in ->writepage().

Wu Fengguang described in 'commit 971767ca':
"writeback: fix dirtied pages accounting on redirty
De-account the accumulative dirty counters on page redirty.

Page redirties (very common in ext4) will introduce mismatch between
counters (a) and (b)

a) NR_DIRTIED, BDI_DIRTIED, tsk->nr_dirtied
b) NR_WRITTEN, BDI_WRITTEN

This will introduce systematic errors in balanced_rate and result in
dirty page position errors (ie. the dirty pages are no longer balanced
around the global/bdi setpoints)."
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Even if f2fs_write_data_page is called by the page reclaiming path, we should
not write the page to provide enough free segments for the worst case scenario.
Otherwise, f2fs can face with no free segment while gc is conducted, resulting
in:

 ------------[ cut here ]------------
 kernel BUG at /home/zeus/f2fs_test/src/fs/f2fs/segment.c:565!
 RIP: 0010:[<ffffffffa02c3b11>]  [<ffffffffa02c3b11>] new_curseg+0x331/0x340 [f2fs]
 Call Trace:
  allocate_segment_by_default+0x204/0x280 [f2fs]
  allocate_data_block+0x108/0x210 [f2fs]
  write_data_page+0x8a/0xc0 [f2fs]
  do_write_data_page+0xe1/0x2a0 [f2fs]
  move_data_page+0x8a/0xf0 [f2fs]
  f2fs_gc+0x446/0x970 [f2fs]
  f2fs_balance_fs+0xb6/0xd0 [f2fs]
  f2fs_write_begin+0x50/0x350 [f2fs]
  ? unlock_page+0x27/0x30
  ? unlock_page+0x27/0x30
  generic_file_buffered_write+0x10a/0x280
  ? file_update_time+0xa3/0xf0
  __generic_file_aio_write+0x1c8/0x3d0
  ? generic_file_aio_write+0x52/0xb0
  ? generic_file_aio_write+0x52/0xb0
  generic_file_aio_write+0x65/0xb0
  do_sync_write+0x5a/0x90
  vfs_write+0xc5/0x1f0
  SyS_write+0x55/0xa0
  system_call_fastpath+0x16/0x1b
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch integrates inode_[inc|dec]_dirty_dents with inc_page_count to remove
redundant calls.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch modifies the use of bi_private to remove pointer chasing for sbi.
Previously, we had a bi_private structure, but it needs memory allocation.
So this patch uses bi_private by the sbi pointer and adds a completion pointer
into the sbi.
This can achieve no memory allocation and nice use of the bi_private.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

In order to make fs consistency, update_inode_page should not be failed all
the time. Otherwise, it is possible to lose some metadata in the inode like
a link count.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If a dentry page is updated, we should call mark_inode_dirty to add the inode
into the dirty list, so that its dentry pages are flushed to the disk.
Otherwise, the inode can be evicted without flush.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Fixed a variety of trivial checkpatch warnings.  The only delta should
be some minor formatting on log strings that were split / too long.
Signed-off-by: NChris Fries <cfries@motorola.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Doing sync_meta_pages with META_FLUSH when checkpoint, we overide rw
using WRITE_FLUSH_FUA. At this time, we also should set
REQ_META|REQ_PRIO.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch should resolve the following bug.

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
3.13.0-rc5.f2fs+ #6 Not tainted
---------------------------------------------------------
kswapd0/41 just changed the state of lock:
 (&sbi->gc_mutex){+.+.-.}, at: [<ffffffffa030503e>] f2fs_balance_fs+0xae/0xd0 [f2fs]
but this lock took another, RECLAIM_FS-READ-unsafe lock in the past:
 (&sbi->cp_rwsem){++++.?}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
Chain exists of:
  &sbi->gc_mutex --> &sbi->cp_mutex --> &sbi->cp_rwsem

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sbi->cp_rwsem);
                               local_irq_disable();
                               lock(&sbi->gc_mutex);
                               lock(&sbi->cp_mutex);
  <Interrupt>
    lock(&sbi->gc_mutex);

 *** DEADLOCK ***

This bug is due to the f2fs_balance_fs call in f2fs_write_data_page.
If f2fs_write_data_page is triggered by wbc->for_reclaim via kswapd, it should
not call f2fs_balance_fs which tries to get a mutex grabbed by original syscall
flow.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

"boo sync" parameter is never referenced in f2fs_wait_on_page_writeback.
We should remove this parameter.
Signed-off-by: NYuan Zhong <yuan.mark.zhong@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

The get_dnode_of_data nullifies inode and node page when error is occurred.

There are two cases that passes inode page into get_dnode_of_data().

1. make_empty_dir()
    -> get_new_data_page()
      -> f2fs_reserve_block(ipage)
	-> get_dnode_of_data()

2. f2fs_convert_inline_data()
    -> __f2fs_convert_inline_data()
      -> f2fs_reserve_block(ipage)
	-> get_dnode_of_data()

This patch adds correct error handling codes when get_dnode_of_data() returns
an error.

At first, f2fs_reserve_block() calls f2fs_put_dnode() whenever reserve_new_block
returns an error.
So, the rule of f2fs_reserve_block() is to nullify inode page when there is any
error internally.

Finally, two callers of f2fs_reserve_block() should call f2fs_put_dnode()
appropriately if they got an error since successful f2fs_reserve_block().
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Change log from v1:
 o handle NULL pointer of grab_cache_page_write_begin() pointed by Chao Yu.

This patch refactors f2fs_convert_inline_data to check a couple of conditions
internally for deciding whether it needs to convert inline_data or not.

So, the new f2fs_convert_inline_data initially checks:
1) f2fs_has_inline_data(), and
2) the data size to be changed.

If the inode has inline_data but the size to fill is less than MAX_INLINE_DATA,
then we don't need to convert the inline_data with data allocation.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

In f2fs_write_begin(), if f2fs_conver_inline_data() returns an error like
-ENOSPC, f2fs should call f2fs_put_page().
Otherwise, it is remained as a locked page, resulting in the following bug.

[<ffffffff8114657e>] sleep_on_page+0xe/0x20
[<ffffffff81146567>] __lock_page+0x67/0x70
[<ffffffff81157d08>] truncate_inode_pages_range+0x368/0x5d0
[<ffffffff81157ff5>] truncate_inode_pages+0x15/0x20
[<ffffffff8115804b>] truncate_pagecache+0x4b/0x70
[<ffffffff81158082>] truncate_setsize+0x12/0x20
[<ffffffffa02a1842>] f2fs_setattr+0x72/0x270 [f2fs]
[<ffffffff811cdae3>] notify_change+0x213/0x400
[<ffffffff811ab376>] do_truncate+0x66/0xa0
[<ffffffff811ab541>] vfs_truncate+0x191/0x1b0
[<ffffffff811ab5bc>] do_sys_truncate+0x5c/0xa0
[<ffffffff811ab78e>] SyS_truncate+0xe/0x10
[<ffffffff81756052>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Hook inline data read/write, truncate, fallocate, setattr, etc.

Files need meet following 2 requirement to inline:
 1) file size is not greater than MAX_INLINE_DATA;
 2) file doesn't pre-allocate data blocks by fallocate().

FI_INLINE_DATA will not be set while creating a new regular inode because
most of the files are bigger than ~3.4K. Set FI_INLINE_DATA only when
data is submitted to block layer, ranther than set it while creating a new
inode, this also avoids converting data from inline to normal data block
and vice versa.

While writting inline data to inode block, the first data block should be
released if the file has a block indexed by i_addr[0].

On the other hand, when a file operation is appied to a file with inline
data, we need to test if this file can remain inline by doing this
operation, otherwise it should be convert into normal file by reserving
a new data block, copying inline data to this new block and clear
FI_INLINE_DATA flag. Because reserve a new data block here will make use
of i_addr[0], if we save inline data in i_addr[0..872], then the first
4 bytes would be overwriten. This problem can be avoided simply by
not using i_addr[0] for inline data.
Signed-off-by: NHuajun Li <huajun.li@intel.com>
Signed-off-by: NHaicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: NWeihong Xu <weihong.xu@intel.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>