linux.git/fs/f2fs/segment.c, branch v4.18

treewide: Use array_size in f2fs_kvzalloc()

2018-06-12T23:19:22+00:00

The f2fs_kvzalloc() function has no 2-factor argument form, so
multiplication factors need to be wrapped in array_size(). This patch
replaces cases of:

        f2fs_kvzalloc(handle, a * b, gfp)

with:
        f2fs_kvzalloc(handle, array_size(a, b), gfp)

as well as handling cases of:

        f2fs_kvzalloc(handle, a * b * c, gfp)

with:

        f2fs_kvzalloc(handle, array3_size(a, b, c), gfp)

This does, however, attempt to ignore constant size factors like:

        f2fs_kvzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
  f2fs_kvzalloc(HANDLE,
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  f2fs_kvzalloc(HANDLE,
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE) * COUNT_ID
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING) * COUNT_ID
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

  f2fs_kvzalloc(HANDLE,
-	SIZE * COUNT
+	array_size(COUNT, SIZE)
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
  f2fs_kvzalloc(HANDLE,
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kvzalloc(HANDLE,
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  f2fs_kvzalloc(HANDLE, C1 * C2 * C3, ...)
|
  f2fs_kvzalloc(HANDLE,
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants.
@@
expression HANDLE;
expression E1, E2;
constant C1, C2;
@@

(
  f2fs_kvzalloc(HANDLE, C1 * C2, ...)
|
  f2fs_kvzalloc(HANDLE,
-	E1 * E2
+	array_size(E1, E2)
  , ...)
)

Signed-off-by: Kees Cook

treewide: Use array_size() in f2fs_kzalloc()

2018-06-12T23:19:22+00:00

The f2fs_kzalloc() function has no 2-factor argument form, so
multiplication factors need to be wrapped in array_size(). This patch
replaces cases of:

        f2fs_kzalloc(handle, a * b, gfp)

with:
        f2fs_kzalloc(handle, array_size(a, b), gfp)

as well as handling cases of:

        f2fs_kzalloc(handle, a * b * c, gfp)

with:

        f2fs_kzalloc(handle, array3_size(a, b, c), gfp)

This does, however, attempt to ignore constant size factors like:

        f2fs_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
  f2fs_kzalloc(HANDLE,
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  f2fs_kzalloc(HANDLE,
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT_ID
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING) * COUNT_ID
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

  f2fs_kzalloc(HANDLE,
-	SIZE * COUNT
+	array_size(COUNT, SIZE)
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
  f2fs_kzalloc(HANDLE,
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  f2fs_kzalloc(HANDLE,
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  f2fs_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  f2fs_kzalloc(HANDLE,
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants.
@@
expression HANDLE;
expression E1, E2;
constant C1, C2;
@@

(
  f2fs_kzalloc(HANDLE, C1 * C2, ...)
|
  f2fs_kzalloc(HANDLE,
-	E1 * E2
+	array_size(E1, E2)
  , ...)
)

Signed-off-by: Kees Cook

f2fs: fix to update mtime correctly

2018-06-04T21:31:11+00:00

If we change system time to the past, get_mtime() will return a
overflowed time, and SIT_I(sbi)->max_mtime will be udpated
incorrectly, this patch fixes the two issues.

Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: clean up symbol namespace

2018-05-31T18:31:53+00:00

As Ted reported:

"Hi, I was looking at f2fs's sources recently, and I noticed that there
is a very large number of non-static symbols which don't have a f2fs
prefix.  There's well over a hundred (see attached below).

As one example, in fs/f2fs/dir.c there is:

unsigned char get_de_type(struct f2fs_dir_entry *de)

This function is clearly only useful for f2fs, but it has a generic
name.  This means that if any other file system tries to have the same
symbol name, there will be a symbol conflict and the kernel would not
successfully build.  It also means that when someone is looking f2fs
sources, it's not at all obvious whether a function such as
read_data_page(), invalidate_blocks(), is a generic kernel function
found in the fs, mm, or block layers, or a f2fs specific function.

You might want to fix this at some point.  Hopefully Kent's bcachefs
isn't similarly using genericly named functions, since that might
cause conflicts with f2fs's functions --- but just as this would be a
problem that we would rightly insist that Kent fix, this is something
that we should have rightly insisted that f2fs should have fixed
before it was integrated into the mainline kernel.

acquire_orphan_inode
add_ino_entry
add_orphan_inode
allocate_data_block
allocate_new_segments
alloc_nid
alloc_nid_done
alloc_nid_failed
available_free_memory
...."

This patch adds "f2fs_" prefix for all non-static symbols in order to:
a) avoid conflict with other kernel generic symbols;
b) to indicate the function is f2fs specific one instead of generic
one;

Reported-by: Theodore Ts'o 
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix to let caller retry allocating block address

2018-05-31T18:31:53+00:00

Configure io_bits with 2 and enable LFS mode, generic/013 reports below dmesg:

BUG: unable to handle kernel NULL pointer dereference at 00000104
*pdpt = 0000000029b7b001 *pde = 0000000000000000
Oops: 0002 [#1] PREEMPT SMP
Modules linked in: crc32_generic zram f2fs(O) rfcomm bnep bluetooth ecdh_generic snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq pcbc joydev snd_seq_device aesni_intel snd_timer aes_i586 snd crypto_simd cryptd soundcore i2c_piix4 serio_raw mac_hid video parport_pc ppdev lp parport hid_generic psmouse usbhid hid e1000
CPU: 0 PID: 11161 Comm: fsstress Tainted: G           O      4.17.0-rc2 #38
Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
EIP: f2fs_submit_page_write+0x28d/0x550 [f2fs]
EFLAGS: 00010206 CPU: 0
EAX: e863dcd8 EBX: 00000000 ECX: 00000100 EDX: 00000200
ESI: e863dcf4 EDI: f6f82768 EBP: e863dbb0 ESP: e863db74
 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
CR0: 80050033 CR2: 00000104 CR3: 29a62020 CR4: 000406f0
Call Trace:
 do_write_page+0x6f/0xc0 [f2fs]
 write_data_page+0x4a/0xd0 [f2fs]
 do_write_data_page+0x327/0x630 [f2fs]
 __write_data_page+0x34b/0x820 [f2fs]
 __f2fs_write_data_pages+0x42d/0x8c0 [f2fs]
 f2fs_write_data_pages+0x27/0x30 [f2fs]
 do_writepages+0x1a/0x70
 __filemap_fdatawrite_range+0x94/0xd0
 filemap_write_and_wait_range+0x3d/0xa0
 __generic_file_write_iter+0x11a/0x1f0
 f2fs_file_write_iter+0xdd/0x3b0 [f2fs]
 __vfs_write+0xd2/0x150
 vfs_write+0x9b/0x190
 ksys_write+0x45/0x90
 sys_write+0x16/0x20
 do_fast_syscall_32+0xaa/0x22c
 entry_SYSENTER_32+0x4c/0x7b
EIP: 0xb7fc8c51
EFLAGS: 00000246 CPU: 0
EAX: ffffffda EBX: 00000003 ECX: 09cde000 EDX: 00001000
ESI: 00000003 EDI: 00001000 EBP: 00000000 ESP: bfbded38
 DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b
Code: e8 f9 77 34 c9 8b 45 e0 8b 80 b8 00 00 00 39 45 d8 0f 84 bb 02 00 00 8b 45 e0 8b 80 b8 00 00 00 8d 50 d8 8b 08 89 55 f0 8b 50 04 <89> 51 04 89 0a c7 00 00 01 00 00 c7 40 04 00 02 00 00 8b 45 dc
EIP: f2fs_submit_page_write+0x28d/0x550 [f2fs] SS:ESP: 0068:e863db74
CR2: 0000000000000104
---[ end trace 4cac79c0d1305ee6 ]---

allocate_data_block will submit all sequential pending IOs sorted by a
FIFO list, If we failed to submit other user's IO due to unaligned write,
we will retry to allocate new block address for current IO, then it will
initialize fio.list again, if fio was in the list before, it can break
FIFO list, result in above panic.

Thread A			Thread B
- do_write_page
 - allocate_data_block
  - list_add_tail
  : fioA cached in FIFO list.
				- do_write_page
				 - allocate_data_block
				  - list_add_tail
				  : fioB cached in FIFO list.
				 - f2fs_submit_page_write
				 : fail to submit IO
				 - allocate_data_block
				  - INIT_LIST_HEAD
 - f2fs_submit_page_write
  - list_del  <-- NULL pointer dereference

This patch adds fio.retry parameter to indicate failure status for each
IO, and avoid bailing out if there is still pending IO in FIFO list for
fixing.

Signed-off-by: Chao Yu 

Signed-off-by: Jaegeuk Kim

f2fs: fix to don't trigger writeback during recovery

2018-05-31T18:31:52+00:00

- f2fs_fill_super
 - recover_fsync_data
  - recover_data
   - del_fsync_inode
    - iput
     - iput_final
      - write_inode_now
       - f2fs_write_inode
        - f2fs_balance_fs
         - f2fs_balance_fs_bg
          - sync_dirty_inodes

With data_flush mount option, during recovery, in order to avoid entering
above writeback flow, let's detect recovery status and do skip in
f2fs_balance_fs_bg.

Signed-off-by: Chao Yu 
Signed-off-by: Yunlei He 
Signed-off-by: Jaegeuk Kim

f2fs: clear discard_wake earlier

2018-05-31T18:31:52+00:00

If SBI_NEED_FSCK is set, discard_wake will never be cleared. As a
result, the condition of wait_event_interruptible_timeout() is always
true, which gets discard thread run too frequently.

Signed-off-by: Sheng Yong 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: let discard thread wait a little longer if dev is busy

2018-05-31T18:31:51+00:00

This patch modify discard thread wait policy as below:
	issued       io_interrupted     wait time(ms)
1.        8                 0               50
2.      (0,8)               1               50
3.        0                 1              500 (dev is busy)
4.        0                 0            60000 (no candidates)

Signed-off-by: Yunlei He 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: avoid stucking GC due to atomic write

2018-05-31T18:31:51+00:00

f2fs doesn't allow abuse on atomic write class interface, so except
limiting in-mem pages' total memory usage capacity, we need to limit
atomic-write usage as well when filesystem is seriously fragmented,
otherwise we may run into infinite loop during foreground GC because
target blocks in victim segment are belong to atomic opened file for
long time.

Now, we will detect failure due to atomic write in foreground GC, if
the count exceeds threshold, we will drop all atomic written data in
cache, by this, I expect it can keep our system running safely to
prevent Dos attack.

In addition, his patch adds to show GC skip information in debugfs,
now it just shows count of skipped caused by atomic write.

Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: introduce sbi->gc_mode to determine the policy

2018-05-31T18:31:51+00:00

This is to avoid sbi->gc_thread pointer access.

Signed-off-by: Jaegeuk Kim