For foreground gc, greedy algorithm should be adapted, which makes
this formula work well:

	(2 * (100 / config.overprovision + 1) + 6)

But currently, we fg_gc have a prior to select bg_gc victim segments to gc
first, these victims are selected by cost-benefit algorithm, we can't guarantee
such segments have the small valid blocks, which may destroy the f2fs rule, on
the worstest case, would consume all the free segments.

This patch fix this by add a filter in check_bg_victims, if segment's has # of
valid blocks over overprovision ratio, skip such segments.

Cc: <stable@vger.kernel.org>
Signed-off-by: NHou Pengyang <houpengyang@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Otherwise we can get livelock like below.

[79880.428136] dbench          D    0 18405  18404 0x00000000
[79880.428139] Call Trace:
[79880.428142]  __schedule+0x219/0x6b0
[79880.428144]  schedule+0x36/0x80
[79880.428147]  schedule_timeout+0x243/0x2e0
[79880.428152]  ? update_sd_lb_stats+0x16b/0x5f0
[79880.428155]  ? ktime_get+0x3c/0xb0
[79880.428157]  io_schedule_timeout+0xa6/0x110
[79880.428161]  __lock_page+0xf7/0x130
[79880.428164]  ? unlock_page+0x30/0x30
[79880.428167]  pagecache_get_page+0x16b/0x250
[79880.428171]  grab_cache_page_write_begin+0x20/0x40
[79880.428182]  f2fs_write_begin+0xa2/0xdb0 [f2fs]
[79880.428192]  ? f2fs_mark_inode_dirty_sync+0x16/0x30 [f2fs]
[79880.428197]  ? kmem_cache_free+0x79/0x200
[79880.428203]  ? __mark_inode_dirty+0x17f/0x360
[79880.428206]  generic_perform_write+0xbb/0x190
[79880.428213]  ? file_update_time+0xa4/0xf0
[79880.428217]  __generic_file_write_iter+0x19b/0x1e0
[79880.428226]  f2fs_file_write_iter+0x9c/0x180 [f2fs]
[79880.428231]  __vfs_write+0xc5/0x140
[79880.428235]  vfs_write+0xb2/0x1b0
[79880.428238]  SyS_write+0x46/0xa0
[79880.428242]  entry_SYSCALL_64_fastpath+0x1e/0xad

Fixes: cae96a5c8ab6 ("f2fs: check io submission more precisely")
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In FG_GC process, it will search victim section twice. This will
cause some dirty section with less valid blocks skip garbage
collection.

section # 26425 : valid blocks # 3
142.037567: get_victim_by_default: victim 26425 : valid blocks # 3
142.037585: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244
142.039494: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19022 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24
142.070247: new_curseg: Debug: alloc new segment 26746
142.244341: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26054 ofs_unit = 1, pre_victim_secno = 26054, prefree = 0, free = 243
142.254475: do_garbage_collect: Debug: FG_GC, seg_freed = 1
142.293131: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23466 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244
142.319001: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23467 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244
142.368879: get_victim_by_default: victim 26425 : valid blocks # 3
142.368894: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244
142.378127: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19612 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24
142.416917: new_curseg: Debug: alloc new segment 26054
142.656794: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 25404 ofs_unit = 1, pre_victim_secno = 25404, prefree = 0, free = 243
142.662139: do_garbage_collect: Debug: FG_GC, seg_freed = 1
142.684159: new_curseg: Debug: alloc new segment 25197
142.685059: get_victim_by_default: victim 26425 : valid blocks # 3
142.685079: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 243
142.701427: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26238 ofs_unit = 1, pre_victim_secno = 26238, prefree = 0, free = 243
142.707105: do_garbage_collect: Debug: FG_GC, seg_freed = 1
142.802444: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23473 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244
142.804422: get_victim_by_default: victim 26425 : valid blocks # 3
142.804443: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244
142.851567: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19092 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24
142.865014: new_curseg: Debug: alloc new segment 26238
143.082245: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26307 ofs_unit = 1, pre_victim_secno = 26307, prefree = 0, free = 244
143.088252: do_garbage_collect: Debug: FG_GC, seg_freed = 1
143.128307: new_curseg: Debug: alloc new segment 25404
143.181846: get_victim_by_default: victim 26425 : valid blocks # 3
143.181872: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244
Signed-off-by: NYunlei He <heyunlei@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds min_cost of each victims.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

It turns out a stakable filesystem like sdcardfs in AOSP can trigger multiple
vfs_create() to lower filesystem. In that case, f2fs will add multiple dentries
having same name which breaks filesystem consistency.

Until upper layer fixes, let's work around by f2fs, which shows actually not
much performance regression.

Cc: <stable@vger.kernel.org>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch shows actual device information in the tracepoints.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We have had node chains, but haven't used it so far due to stale node blocks.
Now, we have crc|cp_ver in node footer and give random cp_ver at format time,
we can start to use it again.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In android, since SElinux is enable, security policy will be appliedd for
each file, it stores in inode as an xattr entry, so it will take one 4k
size node block additionally for each file.

Let's enable inline_xattr by default in order to save storage space.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces new mount option 'noinline_xattr', so we can disable
inline xattr functionality which is already set as a default mount option.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We've not seen this buggy case for a long time, so it's time to avoid this
unnecessary get_node_info() call which reading NAT page to cache nat entry.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Let's avoid build_free_nids() in checkpoint path.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Currently, if we call fsync after updating the xattr date belongs to the
file, f2fs needs to trigger checkpoint to keep xattr data consistent. But,
this policy cause low performance as checkpoint will block most foreground
operations and cause unneeded and unrelated IOs around checkpoint.

This patch will reuse regular file recovery policy for xattr node block,
so, we change to write xattr node block tagged with fsync flag to warm
area instead of cold area, and during recovery, we search warm node chain
for fsynced xattr block, and do the recovery.

So, for below application IO pattern, performance can be improved
obviously:
- touch file
- create/update/delete xattr entry in file
- fsync file
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Declare fscrypt_operations structure as const as it is only stored in
the s_cop field of a super_block structure. This field is of type const,
so fscrypt_operations structure having this property can be made const
too.

File size before: fs/f2fs/super.o
   text	   data	    bss	    dec	    hex	filename
  54131	  31355	    184	  85670	  14ea6	fs/f2fs/super.o

File size after: fs/f2fs/super.o
   text	   data	    bss	    dec	    hex	filename
  54227	  31259	    184	  85670	  14ea6	fs/f2fs/super.o
Signed-off-by: NBhumika Goyal <bhumirks@gmail.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If we mounted f2fs successfully, let's show current checkpoint version.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

There is a typo "f2f2" in f2fs.txt, this patch fixes it.
Signed-off-by: NTiezhu Yang <kernelpatch@126.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch removes REQ_PREFLUSH in the nobarrier case.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If the cached bio has the last page's index, then we need to submit it.
Otherwise, we don't need to submit it and can wait for further IO merges.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch check IO submission more precisely than previous rough check.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces __write_data_page to call it by f2fs_write_cache_pages
directly..
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We need to flush data writes before flushing last node block writes by using
FUA with PREFLUSH. We don't need to guarantee precedent node writes since if
those are not written, we can't reach to the last node block when scanning
node block chain during roll-forward recovery.
Afterwards f2fs_wait_on_page_writeback guarantees all the IO submission to
disk, which builds a valid node block chain.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch just moves write_node_page and introduces an inner function.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch moves the tracepoint location for flush command.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch shows cached # of APPEND and UPDATE inode entries.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

1) Nine coding style warnings below have been resolved:
"Missing a blank line after declarations"

2) 435 coding style warnings below have been resolved:
"function definition argument 'x' should also have an identifier name"

3) Two coding style warnings below have been resolved:
"macros should not use a trailing semicolon"
Signed-off-by: NDongOh Shin <doscode.kr@gmail.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Two coding style errors below have been resolved:
"Macros with complex values should be enclosed in parentheses"

And a coding style error below has been resolved:
"space prohibited before that ',' (ctx:WxW)"
Signed-off-by: NDongOh Shin <doscode.kr@gmail.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We missed two functions declared as static functions.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch shows the fault injection mount option in
f2fs_show_options().
Signed-off-by: NKaixu Xia <xiakaixu@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We only allocate flush merge control structure sbi::sm_info::fcc_info when
flush_merge option is on, but in f2fs_issue_flush we still try to access
member of the control structure without that option, it incurs panic as
show below, fix it.

Call Trace:
 __remove_ino_entry+0xa9/0xc0 [f2fs]
 f2fs_do_sync_file.isra.27+0x214/0x6d0 [f2fs]
 f2fs_sync_file+0x18/0x20 [f2fs]
 vfs_fsync_range+0x3d/0xb0
 __do_page_fault+0x261/0x4d0
 do_fsync+0x3d/0x70
 SyS_fsync+0x10/0x20
 do_syscall_64+0x6e/0x180
 entry_SYSCALL64_slow_path+0x25/0x25
RIP: 0033:0x7f18ce260de0
RSP: 002b:00007ffdd4589258 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f18ce260de0
RDX: 0000000000000006 RSI: 00000000016c0360 RDI: 0000000000000003
RBP: 00000000016c0360 R08: 000000000000ffff R09: 000000000000001f
R10: 00007ffdd4589020 R11: 0000000000000246 R12: 00000000016c0100
R13: 0000000000000000 R14: 00000000016c1f00 R15: 00000000016c0100
Code: fb 81 e3 00 08 00 00 48 89 45 a0 0f 1f 44 00 00 31 c0 85 db 75 27 41 81 e7 00 04 00 00 74 0c 41 8b 45 20 85 c0 0f 85 81 00 00 00 <f0> 41 ff 45 20 4c 89 e7 e8 f8 e9 ff ff f0 41 ff 4d 20 48 83 c4
RIP: f2fs_issue_flush+0x5b/0x170 [f2fs] RSP: ffffc90003b5fd78
CR2: 0000000000000020
---[ end trace a09314c24f037648 ]---
Reported-by: NShuoran Liu <liushuoran@huawei.com>
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We use following method to calculate size with current page index:
size = index << PAGE_SHIFT
If type of index has only 32-bits size, left shifting will incur overflow,
which makes result incorrect.

So let's cast index with 64-bits type to avoid such issue.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Previously, in getxattr we will load all entries both in inline xattr and
xattr node block, and then do the lookup in all entries, but our lookup
flow shows low efficiency, since if we can lookup and hit in inline xattr
of inode page cache first, we don't need to load and lookup xattr node
block, which can obviously save cpu time and IO latency.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: initialize NULL to avoid warning]
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fix a typo in f2fs.txt
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

A dead loop can be triggered in f2fs_fiemap() using the test case
as below:

	...
	fd = open();
	fallocate(fd, 0, 0, 4294967296);
	ioctl(fd, FS_IOC_FIEMAP, fiemap_buf);
	...

It's caused by an overflow in __get_data_block():
	...
	bh->b_size = map.m_len << inode->i_blkbits;
	...
map.m_len is an unsigned int, and bh->b_size is a size_t which is 64 bits
on 64 bits archtecture, type conversion from an unsigned int to a size_t
will result in an overflow.

In the above-mentioned case, bh->b_size will be zero, and f2fs_fiemap()
will call get_data_block() at block 0 again an again.

Fix this by adding a force conversion before left shift.
Signed-off-by: NWei Fang <fangwei1@huawei.com>
Acked-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Sheng Yong reports needless preallocation if write(small_buffer, large_size)
is called.

In that case, f2fs preallocates large_size, but vfs returns early due to
small_buffer size. Let's detect it before preallocation phase in f2fs.
Reported-by: NSheng Yong <shengyong1@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds stat information for flush and discard commands.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a kernel thread to issue discard commands.
It proposes three states, D_PREP, D_SUBMIT, and D_DONE to identify current
bio status.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds discard_cmd_control with the existing discarding controls.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch modifies stat information more clearly.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch simply cleans up the names for flush/discard commands.
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a mirror for sit version bitmap, and use it to detect
in-memory bitmap corruption which may be caused by bit-transition of
cache or memory overflow.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a mirror for nat version bitmap, and use it to detect
in-memory bitmap corruption which may be caused by bit-transition of
cache or memory overflow.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>