init_f2fs_fs does:
    1) f2fs_build_trace_ios
    2) init_inodecache
    3) create_node_manager_caches
    4) create_segment_manager_caches
    5) create_checkpoint_caches
    6) create_extent_cache
    7) kset_create_and_add
    8) kobject_init_and_add
    9) register_shrinker
    10) register_filesystem
    11) f2fs_create_root_stats
    12) proc_mkdir

exit_f2fs_fs should do cleanup in the reverse order
to make the code more clear.
Signed-off-by: Tiezhu Yang <kernelpatch@126.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch uses percpu_counter to avoid stat_lock.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch uses percpu_count for sbi->alloc_valid_block_count.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds percpu_counter for # of dirty pages in inode.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch substitutes percpu_counter for atomic_counter when counting
various types of pages.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This can reduce page counting overhead.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

It needs to maintain dirty file inodes only if DATA_FLUSH is set.
Otherwise, let's avoid its overhead.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch introduces a new struct f2fs_fault_info and a global f2fs_fault
to save fault injection status. Fault injection entries are created in
/sys/fs/f2fs/fault_injection/ during initializing f2fs module.
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

No need inc dirty pages under inode lock
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Fix two bugs in error path of f2fs_move_rehashed_dirents:
 - release dir's inode page if fail to call kmalloc
 - recover i_current_depth if fail to converting
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

With below steps, we will see that dentry page becoming unaccessable later.
This is because we forget updating i_current_depth in inode during inline
dentry conversion, after that, once we failed at somewhere, it will leave
i_current_depth as 0 in non-inline directory. Then, during ->lookup, the
current_depth value makes all dentry pages in first level invisible. Fix
it.

1) mount f2fs with inline_dentry option
2) mkdir dir
3) touch 180 files named [0-179] in dir
4) touch 180 in dir (fail after inline dir conversion)
5) ll dir

ls: cannot access /mnt/f2fs/dir/0: No such file or directory
ls: cannot access /mnt/f2fs/dir/1: No such file or directory
ls: cannot access /mnt/f2fs/dir/2: No such file or directory
ls: cannot access /mnt/f2fs/dir/3: No such file or directory
ls: cannot access /mnt/f2fs/dir/4: No such file or directory

drwxr-xr-x 2 root root 4096  may 13 21:47 ./
drwxr-xr-x 3 root root 4096  may 13 21:46 ../
-????????? ? ?    ?       ?             ? 0
-????????? ? ?    ?       ?             ? 1
-????????? ? ?    ?       ?             ? 10
-????????? ? ?    ?       ?             ? 100
-????????? ? ?    ?       ?             ? 101
-????????? ? ?    ?       ?             ? 102
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Below backtrace info was reported by Yunlei He:

Call Trace:
 [<ffffffff817a9395>] schedule+0x35/0x80
 [<ffffffff817abb7d>] rwsem_down_read_failed+0xed/0x130
 [<ffffffff813c12a8>] call_rwsem_down_read_failed+0x18/0x
 [<ffffffff817ab1d0>] down_read+0x20/0x30
 [<ffffffffa02a1a12>] f2fs_evict_inode+0x242/0x3a0 [f2fs]
 [<ffffffff81217057>] evict+0xc7/0x1a0
 [<ffffffff81217cd6>] iput+0x196/0x200
 [<ffffffff812134f9>] __dentry_kill+0x179/0x1e0
 [<ffffffff812136f9>] dput+0x199/0x1f0
 [<ffffffff811fe77b>] __fput+0x18b/0x220
 [<ffffffff811fe84e>] ____fput+0xe/0x10
 [<ffffffff81097427>] task_work_run+0x77/0x90
 [<ffffffff81074d62>] exit_to_usermode_loop+0x73/0xa2
 [<ffffffff81003b7a>] do_syscall_64+0xfa/0x110
 [<ffffffff817acf65>] entry_SYSCALL64_slow_path+0x25/0x25

Call Trace:
 [<ffffffff817a9395>] schedule+0x35/0x80
 [<ffffffff81216dc3>] __wait_on_freeing_inode+0xa3/0xd0
 [<ffffffff810bc300>] ? autoremove_wake_function+0x40/0x4
 [<ffffffff8121771d>] find_inode_fast+0x7d/0xb0
 [<ffffffff8121794a>] ilookup+0x6a/0xd0
 [<ffffffffa02bc740>] sync_node_pages+0x210/0x650 [f2fs]
 [<ffffffff8122e690>] ? do_fsync+0x70/0x70
 [<ffffffffa02b085e>] block_operations+0x9e/0xf0 [f2fs]
 [<ffffffff8137b795>] ? bio_endio+0x55/0x60
 [<ffffffffa02b0942>] write_checkpoint+0x92/0xba0 [f2fs]
 [<ffffffff8117da57>] ? mempool_free_slab+0x17/0x20
 [<ffffffff8117de8b>] ? mempool_free+0x2b/0x80
 [<ffffffff8122e690>] ? do_fsync+0x70/0x70
 [<ffffffffa02a53e3>] f2fs_sync_fs+0x63/0xd0 [f2fs]
 [<ffffffff8129630f>] ? ext4_sync_fs+0xbf/0x190
 [<ffffffff8122e6b0>] sync_fs_one_sb+0x20/0x30
 [<ffffffff812002e9>] iterate_supers+0xb9/0x110
 [<ffffffff8122e7b5>] sys_sync+0x55/0x90
 [<ffffffff81003ae9>] do_syscall_64+0x69/0x110
 [<ffffffff817acf65>] entry_SYSCALL64_slow_path+0x25/0x25

With following excuting serials, we will set inline_node in inode page
after inode was unlinked, result in a deadloop described as below:
1. open file
2. write file
3. unlink file
4. write file
5. close file

Thread A				Thread B
 - dput
  - iput_final
   - inode->i_state |= I_FREEING
   - evict
    - f2fs_evict_inode
					 - f2fs_sync_fs
					  - write_checkpoint
					   - block_operations
					    - f2fs_lock_all (down_write(cp_rwsem))
     - f2fs_lock_op (down_read(cp_rwsem))
					    - sync_node_pages
					     - ilookup
					      - find_inode_fast
					       - __wait_on_freeing_inode
					         (wait on I_FREEING clear)

Here, we change to set inline_node flag only for linked inode for fixing.
Reported-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Tested-by: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: stable@vger.kernel.org # v4.6
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

We don't need to use f2fs_bug_on() to treat with any error case when allocating
a block during recovery.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This adds debug information for # of orphan inodes.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch tries to speedup fzero_range by making space preallocation and
address removal of blocks in one dnode page as in batch operation.

In virtual machine, with zram driver:

dd if=/dev/zero of=/mnt/f2fs/file bs=1M count=4096
time xfs_io -f /mnt/f2fs/file -c "fzero 0 4096M"

Before:
real	0m3.276s
user	0m0.008s
sys	0m3.260s

After:
real	0m1.568s
user	0m0.000s
sys	0m1.564s
Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: consider ENOSPC case]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch introduces reserve_new_blocks to make preallocation of multi
blocks as in batch operation, so it can avoid lots of redundant
operation, result in better performance.

In virtual machine, with rotational device:

time fallocate -l 32G /mnt/f2fs/file

Before:
real	0m4.584s
user	0m0.000s
sys	0m4.580s

After:
real	0m0.292s
user	0m0.000s
sys	0m0.272s

In x86, with SSD:

time fallocate -l 500G $MNT/testfile

Before : 24.758 s
After  :  1.604 s
Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: fix bugs and add performance numbers measured in x86.]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

atomic/volatile ioctl interfaces are exposed to user like other file
operation interface, it needs to make them getting exclusion against
to each other to avoid potential conflict among these operations
in concurrent scenario.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

In interfaces of ioctl, mnt_{want,drop}_write_file should be used for:
- get exclusion against file system freezing which may used by lvm
  snapshot.
- do telling filesystem that a write is about to be performed on it, and
  make sure that the writes are permitted.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Previously f2fs_preallocate_blocks() tries to allocate unaligned blocks.
In f2fs_write_begin(), however, prepare_write_begin() does not skip its
allocation due to (len != 4KB).
So, it needs locking node page twice unexpectedly.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch enables reading node blocks in advance when truncating large
data blocks.

 > time rm $MNT/testfile (500GB) after drop_cachees
Before : 9.422 s
After  : 4.821 s
Reported-by: Stephen Bates <stephen.bates@microsemi.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch is to improve the expand_inode speed in fallocate by allocating
data blocks as many as possible in single locked node page.

In SSD,
 # time fallocate -l 500G $MNT/testfile

Before : 1m 33.410 s
After  : 24.758 s
Reported-by: Stephen Bates <stephen.bates@microsemi.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

When testing f2fs with inline_dentry option, generic/342 reports:
VFS: Busy inodes after unmount of dm-0. Self-destruct in 5 seconds.  Have a nice day...

After rmmod f2fs module, kenrel shows following dmesg:
 =============================================================================
 BUG f2fs_inode_cache (Tainted: G           O   ): Objects remaining in f2fs_inode_cache on __kmem_cache_shutdown()
 -----------------------------------------------------------------------------

 Disabling lock debugging due to kernel taint
 INFO: Slab 0xf51ca0e0 objects=22 used=1 fp=0xd1e6fc60 flags=0x40004080
 CPU: 3 PID: 7455 Comm: rmmod Tainted: G    B      O    4.6.0-rc4+ #16
 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
  00000086 00000086 d062fe18 c13a83a0 f51ca0e0 d062fe38 d062fea4 c11c7276
  c1981040 f51ca0e0 00000016 00000001 d1e6fc60 40004080 656a624f 20737463
  616d6572 6e696e69 6e692067 66326620 6e695f73 5f65646f 68636163 6e6f2065
 Call Trace:
  [<c13a83a0>] dump_stack+0x5f/0x8f
  [<c11c7276>] slab_err+0x76/0x80
  [<c11cbfc0>] ? __kmem_cache_shutdown+0x100/0x2f0
  [<c11cbfc0>] ? __kmem_cache_shutdown+0x100/0x2f0
  [<c11cbfe5>] __kmem_cache_shutdown+0x125/0x2f0
  [<c1198a38>] kmem_cache_destroy+0x158/0x1f0
  [<c176b43d>] ? mutex_unlock+0xd/0x10
  [<f8f15aa3>] exit_f2fs_fs+0x4b/0x5a8 [f2fs]
  [<c10f596c>] SyS_delete_module+0x16c/0x1d0
  [<c1001b10>] ? do_fast_syscall_32+0x30/0x1c0
  [<c13c59bf>] ? __this_cpu_preempt_check+0xf/0x20
  [<c10afa7d>] ? trace_hardirqs_on_caller+0xdd/0x210
  [<c10ad50b>] ? trace_hardirqs_off+0xb/0x10
  [<c1001b81>] do_fast_syscall_32+0xa1/0x1c0
  [<c176d888>] sysenter_past_esp+0x45/0x74
 INFO: Object 0xd1e6d9e0 @offset=6624
 kmem_cache_destroy f2fs_inode_cache: Slab cache still has objects
 CPU: 3 PID: 7455 Comm: rmmod Tainted: G    B      O    4.6.0-rc4+ #16
 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
  00000286 00000286 d062fef4 c13a83a0 f174b000 d062ff14 d062ff28 c1198ac7
  c197fe18 f3c5b980 d062ff20 000d04f2 d062ff0c d062ff0c d062ff14 d062ff14
  f8f20dc0 fffffff5 d062e000 d062ff30 f8f15aa3 d062ff7c c10f596c 73663266
 Call Trace:
  [<c13a83a0>] dump_stack+0x5f/0x8f
  [<c1198ac7>] kmem_cache_destroy+0x1e7/0x1f0
  [<f8f15aa3>] exit_f2fs_fs+0x4b/0x5a8 [f2fs]
  [<c10f596c>] SyS_delete_module+0x16c/0x1d0
  [<c1001b10>] ? do_fast_syscall_32+0x30/0x1c0
  [<c13c59bf>] ? __this_cpu_preempt_check+0xf/0x20
  [<c10afa7d>] ? trace_hardirqs_on_caller+0xdd/0x210
  [<c10ad50b>] ? trace_hardirqs_off+0xb/0x10
  [<c1001b81>] do_fast_syscall_32+0xa1/0x1c0
  [<c176d888>] sysenter_past_esp+0x45/0x74

The reason is: in recovery flow, we use delayed iput mechanism for directory
which has recovered dentry block. It means the reference of inode will be
held until last dirty dentry page being writebacked.

But when we mount f2fs with inline_dentry option, during recovery, dirent
may only be recovered into dir inode page rather than dentry page, so there
are no chance for us to release inode reference in ->writepage when
writebacking last dentry page.

We can call paired iget/iput explicityly for inline_dentry case, but for
non-inline_dentry case, iput will call writeback_single_inode to write all
data pages synchronously, but during recovery, ->writepages of f2fs skips
writing all pages, result in losing dirent.

This patch fixes this issue by obsoleting old mechanism, and introduce a
new dir_list to hold all directory inodes which has recovered datas until
finishing recovery.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch allows fscrypto to handle a second key prefix given by filesystem.
The main reason is to provide backward compatibility, since previously f2fs
used "f2fs:" as a crypto prefix instead of "fscrypt:".
Later, ext4 should also provide key_prefix() to give "ext4:".

One concern decribed by Ted would be kinda double check overhead of prefixes.
In x86, for example, validate_user_key consumes 8 ms after boot-up, which turns
out derive_key_aes() consumed most of the time to load specific crypto module.
After such the cold miss, it shows almost zero latencies, which treats as a
negligible overhead.
Note that request_key() detects wrong prefix in prior to derive_key_aes() even.

Cc: Ted Tso <tytso@mit.edu>
Cc: stable@vger.kernel.org # v4.6
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The following panic occurs when truncating inode which has inline
xattr to max filesize.

[<ffffffffa013d3be>] get_dnode_of_data+0x4e/0x580 [f2fs]
[<ffffffffa013aca1>] ? read_node_page+0x51/0x90 [f2fs]
[<ffffffffa013ad99>] ? get_node_page.part.34+0xb9/0x170 [f2fs]
[<ffffffffa01235b1>] truncate_blocks+0x131/0x3f0 [f2fs]
[<ffffffffa01238e3>] f2fs_truncate+0x73/0x100 [f2fs]
[<ffffffffa01239d2>] f2fs_setattr+0x62/0x2a0 [f2fs]
[<ffffffff811a72c8>] notify_change+0x158/0x300
[<ffffffff8118a42b>] do_truncate+0x6b/0xa0
[<ffffffff8118e539>] ? __sb_start_write+0x49/0x100
[<ffffffff8118a798>] do_sys_ftruncate.constprop.12+0x118/0x170
[<ffffffff8118a82e>] SyS_ftruncate+0xe/0x10
[<ffffffff8169efcf>] tracesys+0xe1/0xe6
[<ffffffffa0139ae0>] get_node_path+0x210/0x220 [f2fs]
 <ffff880206a89ce8>
--[ end trace 5fea664dfbcc6625 ]---

The reason is truncate_blocks tries to truncate all node and data blocks
start from specified block offset with value of (max filesize / block
size), but actually, our valid max block offset is (max filesize / block
size) - 1, so f2fs detects such invalid block offset with BUG_ON in
truncation path.

This patch lets f2fs skip truncating data which is exceeding max
filesize.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Currently, generic_block_bmap is used in f2fs_bmap, its semantics is when
the mapping is been found, return position of target physical block,
otherwise return zero.

But, previously, when there is no mapping info for specified logical block,
f2fs_bmap will map target physical block to a uninitialized variable, which
should be wrong. Fix it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch removes an obsolete variable used in add_free_nid.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Even if an inode failed to release its blocks, it should be kept in an orphan
inode list, so it will be released later.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Restructure struct seg_entry to eliminate holes in it, after that,
in 32-bits machine, it reduces size from 32 bytes to 24 bytes; in
64-bits machine, it reduces size from 56 bytes to 40 bytes.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Reuse get_extent_info for readability.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Each of fields in struct f2fs_xattr_entry will be assigned later,
so previously we don't need to memset the struct.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

In find_fsync_dnodes, get_tmp_page will read dnode page synchronously,
previously, ra_meta_page did the same work, which is redundant, remove
it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch modifies to retry truncating node blocks in -ENOMEM case.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

When unmounting filesystem, we should release all the ino entries.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch fixes a couple of bugs regarding to orphan inodes when handling
errors.

This tries to
 - call alloc_nid_done with add_orphan_inode in handle_failed_inode
 - let truncate blocks in f2fs_evict_inode
 - not make a bad inode due to i_mode change
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch injects ENOSPC failures.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds page allocation failures.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch injects kmalloc failure given a fault injection rate.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds a mount option to select fault ratio.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch converts grab_cache_page to f2fs_grab_cache_page.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>