f2fs: put the bio when issue_flush completed

Put the bio when the flush cmd issued, it also can fix the following
kmemleak:
unreferenced object 0xffff8800270c73c0 (size 200):
  comm "f2fs_flush-7:0", pid 27161, jiffies 4312127988 (age 988.503s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 40 07 81 19 01 88 ff ff  ........@.......
    01 00 00 00 00 00 00 f0 11 14 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81559866>] kmemleak_alloc+0x72/0x96
    [<ffffffff81156f7e>] slab_post_alloc_hook+0x28/0x2a
    [<ffffffff811595b1>] kmem_cache_alloc+0xec/0x157
    [<ffffffff8111924d>] mempool_alloc_slab+0x15/0x17
    [<ffffffff81119513>] mempool_alloc+0x71/0x138
    [<ffffffff81193548>] bio_alloc_bioset+0x93/0x18c
    [<ffffffffa040f857>] issue_flush_thread+0x8d/0x145 [f2fs]
    [<ffffffff8107ac16>] kthread+0xba/0xc2
    [<ffffffff81571b2c>] ret_from_fork+0x7c/0xb0
    [<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: use __GFP_ZERO to avoid appending set-NULL

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: enable flush_merge only in f2fs is not read-only

Enable flush_merge only in f2fs is not read-only, so does the mount
option show.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: avoid to conduct roll-forward due to the remained garbage
 blocks

The f2fs always scans the next chain of direct node blocks.
But some garbage blocks are able to be remained due to no discard support or
SSR triggers.
This occasionally wreaks recovering wrong inodes that were used or BUG_ONs
due to reallocating node ids as follows.

When mount this f2fs image:
http://linuxtesting.org/downloads/f2fs_fault_image.zip
BUG_ON is triggered in f2fs driver (messages below are generated on
kernel 3.13.2; for other kernels output is similar):

kernel BUG at fs/f2fs/node.c:215!
 Call Trace:
 [<ffffffffa032ebad>] recover_inode_page+0x1fd/0x3e0 [f2fs]
 [<ffffffff811446e7>] ? __lock_page+0x67/0x70
 [<ffffffff81089990>] ? autoremove_wake_function+0x50/0x50
 [<ffffffffa0337788>] recover_fsync_data+0x1398/0x15d0 [f2fs]
 [<ffffffff812b9e5c>] ? selinux_d_instantiate+0x1c/0x20
 [<ffffffff811cb20b>] ? d_instantiate+0x5b/0x80
 [<ffffffffa0321044>] f2fs_fill_super+0xb04/0xbf0 [f2fs]
 [<ffffffff811b861e>] ? mount_bdev+0x7e/0x210
 [<ffffffff811b8769>] mount_bdev+0x1c9/0x210
 [<ffffffffa0320540>] ? validate_superblock+0x210/0x210 [f2fs]
 [<ffffffffa031cf8d>] f2fs_mount+0x1d/0x30 [f2fs]
 [<ffffffff811b9497>] mount_fs+0x47/0x1c0
 [<ffffffff81166e00>] ? __alloc_percpu+0x10/0x20
 [<ffffffff811d4032>] vfs_kern_mount+0x72/0x110
 [<ffffffff811d6763>] do_mount+0x493/0x910
 [<ffffffff811615cb>] ? strndup_user+0x5b/0x80
 [<ffffffff811d6c70>] SyS_mount+0x90/0xe0
 [<ffffffff8166f8d9>] system_call_fastpath+0x16/0x1b

Found by Linux File System Verification project (linuxtesting.org).

Reported-by: Andrey Tsyvarev <tsyvarev@ispras.ru>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: check the acl's validity before setting

Before setting the acl, call posix_acl_valid() to check if it is
valid or not.

Signed-off-by: zhangzhen <zhenzhang.zhang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: fix wrong statistics of inline data

If we remove a file that has inline data after mount, our statistics turns to
inaccurate.

cat /sys/kernel/debug/f2fs/status
  - Inline_data Inode: 4294967295

Let's add stat_inc_inline_inode() to stat inline info of the file when lookup.

Change log from v1:
 o stat in f2fs_lookup() instead of in do_read_inode() for excluding wrong stat.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: call redirty_page_for_writepage

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: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: adjust free mem size to flush dentry blocks

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: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: remove costly dirty_dir_inode operations

This patch removes list opeations in handling dirty dir inodes.
Previously, F2FS traverses whole the list of dirty dir inodes to check whether
there is an existing inode or not, resulting in heavy CPU overheads.

So this patch removes such the traverse operations by adding FI_DIRTY_DIR to
indicate the inode lies on the list or not.
Through this simple flag, we can remove redundant operations gracefully.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>