f2fs: reduce searching region of segmap when free section

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: add f2fs_balance_fs for direct IO

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: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: support ->rename2()

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Conflicts:
	fs/f2fs/namei.c
f2fs: avoid use invalid mapping of node_inode when evict meta inode

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: Andrey Tsyvarev <tsyvarev@ispras.ru>
Tested-by: Andrey Tsyvarev <tsyvarev@ispras.ru>
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Conflicts:
	fs/f2fs/inode.c
f2fs: fix to put root inode in error path of fill_super

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: Chao Yu <chao2.yu@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: add nobarrier mount option

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: punch the core function for inode management

This patch punches out the core functions to manage the inode numbers.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: add infra for ino management

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: use radix_tree for ino management

For better ino management, this patch replaces the data structure from list
to radix tree.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: add info of appended or updated data writes

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: skip unnecessary data writes during fsync

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: enable in-place-update for fdatasync

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: fix wrong condition for unlikely

This patch fixes the wrongly used unlikely condition.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: test before set/clear bits

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: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: avoid retrying wrong recovery routine when error was occurred

This patch eliminates the propagation of recovery errors to the next mount.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: add tracepoint for f2fs_issue_flush

This patch adds a tracepoint for f2fs_issue_flush.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: remove redundant lines in allocate_data_block

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Dongho Sim <dh.sim@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: fix coding style

This patch fixes wrong coding style.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: reduce competition among node page writes

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: add tracepoint for f2fs_direct_IO

This patch adds a tracepoint for f2fs_direct_IO.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Conflicts:
	fs/f2fs/data.c