Commit graph

20 commits

Author SHA1 Message Date
Chao Yu
8908e75310 f2fs: fix to verify tpage before releasing in f2fs_free_dic()
In below error path, tpages[i] could be NULL, fix to check it before
releasing it.
- f2fs_read_multi_pages
 - f2fs_alloc_dic
  - f2fs_free_dic

Fixes: 61fbae2b2b ("f2fs: fix to avoid NULL pointer dereference")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-04-03 10:21:31 -07:00
Chao Yu
80d0d45ab5 f2fs: clean up dic->tpages assignment
Just cleanup, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-04-03 10:21:31 -07:00
Chao Yu
50cfa66f0d f2fs: compress: support zstd compress algorithm
Add zstd compress algorithm support, use "compress_algorithm=zstd"
mountoption to enable it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-04-03 10:21:10 -07:00
Chao Yu
23b1faaade f2fs: compress: add .{init,destroy}_decompress_ctx callback
Add below two callback interfaces in struct f2fs_compress_ops:

	int (*init_decompress_ctx)(struct decompress_io_ctx *dic);
	void (*destroy_decompress_ctx)(struct decompress_io_ctx *dic);

Which will be used by zstd compress algorithm later.

In addition, this patch adds callback function pointer check, so that
specified algorithm can avoid defining unneeded functions.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-30 20:46:26 -07:00
Chao Yu
09ff48011e f2fs: compress: fix to call missing destroy_compress_ctx()
Otherwise, it will cause memory leak.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-30 20:46:26 -07:00
Chao Yu
887347a09a f2fs: clean up {cic,dic}.ref handling
{cic,dic}.ref should be initialized to number of compressed pages,
let's initialize it directly rather than doing w/
f2fs_set_compressed_page().

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-30 20:46:26 -07:00
Chao Yu
79bbefb19f f2fs: fix NULL pointer dereference in f2fs_verity_work()
If both compression and fsverity feature is on, generic/572 will
report below NULL pointer dereference bug.

 BUG: kernel NULL pointer dereference, address: 0000000000000018
 RIP: 0010:f2fs_verity_work+0x60/0x90 [f2fs]
 #PF: supervisor read access in kernel mode
 Workqueue: fsverity_read_queue f2fs_verity_work [f2fs]
 RIP: 0010:f2fs_verity_work+0x60/0x90 [f2fs]
 Call Trace:
  process_one_work+0x16c/0x3f0
  worker_thread+0x4c/0x440
  ? rescuer_thread+0x350/0x350
  kthread+0xf8/0x130
  ? kthread_unpark+0x70/0x70
  ret_from_fork+0x35/0x40

There are two issue in f2fs_verity_work():
- it needs to traverse and verify all pages in bio.
- if pages in bio belong to non-compressed cluster, accessing
decompress IO context stored in page private will cause NULL
pointer dereference.

Fix them.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-30 20:46:25 -07:00
Chao Yu
23c51bed6f f2fs: fix to clear PG_error if fsverity failed
In f2fs_decompress_end_io(), we should clear PG_error flag before page
unlock, otherwise reread will fail due to the flag as described in
commit fb7d70db30 ("f2fs: clear PageError on the read path").

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-30 20:46:24 -07:00
Chao Yu
466357dc9b f2fs: fix potential deadlock on compressed quota file
generic/232 reports below deadlock:

fsstress        D    0 96980  96969 0x00084000
Call Trace:
 schedule+0x4a/0xb0
 io_schedule+0x12/0x40
 __lock_page+0x127/0x1d0
 pagecache_get_page+0x1d8/0x250
 prepare_compress_overwrite+0xe0/0x490 [f2fs]
 f2fs_prepare_compress_overwrite+0x5d/0x80 [f2fs]
 f2fs_write_begin+0x833/0xb90 [f2fs]
 f2fs_quota_write+0x145/0x1e0 [f2fs]
 write_blk+0x36/0x80 [quota_tree]
 do_insert_tree+0x2ac/0x4a0 [quota_tree]
 do_insert_tree+0x26e/0x4a0 [quota_tree]
 qtree_write_dquot+0x70/0x190 [quota_tree]
 v2_write_dquot+0x43/0x90 [quota_v2]
 dquot_acquire+0x77/0x100
 f2fs_dquot_acquire+0x2f/0x60 [f2fs]
 dqget+0x310/0x450
 dquot_transfer+0xb2/0x120
 f2fs_setattr+0x11a/0x4a0 [f2fs]
 notify_change+0x349/0x480
 chown_common+0x168/0x1c0
 do_fchownat+0xbc/0xf0
 __x64_sys_lchown+0x21/0x30
 do_syscall_64+0x5f/0x220
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  task                        PC stack   pid father
kworker/u256:0  D    0 103444      2 0x80084000
Workqueue: writeback wb_workfn (flush-251:1)
Call Trace:
 schedule+0x4a/0xb0
 schedule_timeout+0x15e/0x2f0
 io_schedule_timeout+0x19/0x40
 congestion_wait+0x7e/0x120
 f2fs_write_multi_pages+0x12a/0x840 [f2fs]
 f2fs_write_cache_pages+0x48f/0x790 [f2fs]
 f2fs_write_data_pages+0x2db/0x330 [f2fs]
 do_writepages+0x1a/0x60
 __writeback_single_inode+0x3d/0x340
 writeback_sb_inodes+0x225/0x4a0
 wb_writeback+0xf7/0x320
 wb_workfn+0xba/0x470
 process_one_work+0x16c/0x3f0
 worker_thread+0x4c/0x440
 kthread+0xf8/0x130
 ret_from_fork+0x35/0x40

fsstress        D    0  5277   5266 0x00084000
Call Trace:
 schedule+0x4a/0xb0
 rwsem_down_write_slowpath+0x29d/0x540
 block_operations+0x105/0x360 [f2fs]
 f2fs_write_checkpoint+0x101/0x1010 [f2fs]
 f2fs_sync_fs+0xa8/0x130 [f2fs]
 f2fs_do_sync_file+0x1ad/0x890 [f2fs]
 do_fsync+0x38/0x60
 __x64_sys_fdatasync+0x13/0x20
 do_syscall_64+0x5f/0x220
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The root cause is there is potential deadlock between quota data
update and writeback.

Kworker					Thread B			Thread C
- f2fs_write_cache_pages
 - lock whole cluster	--- A
 - f2fs_write_multi_pages
  - f2fs_write_raw_pages
   - f2fs_write_single_data_page
    - f2fs_do_write_data_page
					- f2fs_setattr
					 - f2fs_lock_op	--- B
									- f2fs_write_checkpoint
									 - block_operations
									  - f2fs_lock_all --- B
					 - dquot_transfer
					  - f2fs_quota_write
					   - f2fs_prepare_compress_overwrite
					    - pagecache_get_page --- A
     - f2fs_trylock_op failed	--- B
  - congestion_wait
  - goto rewrite

To fix this issue, during quota file writeback, just redirty all pages
left in cluster rather holding pages' lock in cluster and looping retrying
lock cp_rwsem.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-30 20:46:23 -07:00
Chao Yu
1a67cbe141 f2fs: fix to account compressed blocks in f2fs_compressed_blocks()
por_fsstress reports inconsistent status in orphan inode, the root cause
of this is in f2fs_write_raw_pages() we decrease i_compr_blocks incorrectly
due to wrong calculation in f2fs_compressed_blocks().

So this patch exposes below two functions based on __f2fs_cluster_blocks:
- f2fs_compressed_blocks: get count of compressed blocks in compressed cluster
- f2fs_cluster_blocks: get count of valid blocks (including reserved blocks)
in compressed cluster.

Then use f2fs_compress_blocks() to get correct compressed blocks count in
f2fs_write_raw_pages().

sanity_check_inode: inode (ino=ad80) hash inconsistent i_compr_blocks:2, i_blocks:1, run fsck to fix

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-22 21:16:29 -07:00
Chao Yu
0683728ada f2fs: fix to avoid triggering IO in write path
If we are in write IO path, we need to avoid using GFP_KERNEL.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-19 11:41:26 -07:00
Chao Yu
5df7731f60 f2fs: introduce DEFAULT_IO_TIMEOUT
As Geert Uytterhoeven reported:

for parameter HZ/50 in congestion_wait(BLK_RW_ASYNC, HZ/50);

On some platforms, HZ can be less than 50, then unexpected 0 timeout
jiffies will be set in congestion_wait().

This patch introduces a macro DEFAULT_IO_TIMEOUT to wrap a determinate
value with msecs_to_jiffies(20) to instead HZ/50 to avoid such issue.

Quoted from Geert Uytterhoeven:

"A timeout of HZ means 1 second.
HZ/50 means 20 ms, but has the risk of being zero, if HZ < 50.

If you want to use a timeout of 20 ms, you best use msecs_to_jiffies(20),
as that takes care of the special cases, and never returns 0."

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-19 11:41:26 -07:00
Chao Yu
a2ced1ce10 f2fs: clean up codes with {f2fs_,}data_blkaddr()
- rename datablock_addr() to data_blkaddr().
- wrap data_blkaddr() with f2fs_data_blkaddr() to clean up
parameters.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-19 11:41:25 -07:00
Chao Yu
95978caa13 f2fs: fix to avoid use-after-free in f2fs_write_multi_pages()
In compress cluster, if physical block number is less than logic
page number, race condition will cause use-after-free issue as
described below:

- f2fs_write_compressed_pages
 - fio.page = cic->rpages[0];
 - f2fs_outplace_write_data
					- f2fs_compress_write_end_io
					 - kfree(cic->rpages);
					 - kfree(cic);
 - fio.page = cic->rpages[1];

f2fs_write_multi_pages+0xfd0/0x1a98
f2fs_write_data_pages+0x74c/0xb5c
do_writepages+0x64/0x108
__writeback_single_inode+0xdc/0x4b8
writeback_sb_inodes+0x4d0/0xa68
__writeback_inodes_wb+0x88/0x178
wb_writeback+0x1f0/0x424
wb_workfn+0x2f4/0x574
process_one_work+0x210/0x48c
worker_thread+0x2e8/0x44c
kthread+0x110/0x120
ret_from_fork+0x10/0x18

Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-10 09:18:33 -07:00
Chao Yu
c10c982032 f2fs: cover last_disk_size update with spinlock
This change solves below hangtask issue:

INFO: task kworker/u16:1:58 blocked for more than 122 seconds.
      Not tainted 5.6.0-rc2-00590-g9983bdae4974e #11
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u16:1   D    0    58      2 0x00000000
Workqueue: writeback wb_workfn (flush-179:0)
Backtrace:
 (__schedule) from [<c0913234>] (schedule+0x78/0xf4)
 (schedule) from [<c017ec74>] (rwsem_down_write_slowpath+0x24c/0x4c0)
 (rwsem_down_write_slowpath) from [<c0915f2c>] (down_write+0x6c/0x70)
 (down_write) from [<c0435b80>] (f2fs_write_single_data_page+0x608/0x7ac)
 (f2fs_write_single_data_page) from [<c0435fd8>] (f2fs_write_cache_pages+0x2b4/0x7c4)
 (f2fs_write_cache_pages) from [<c043682c>] (f2fs_write_data_pages+0x344/0x35c)
 (f2fs_write_data_pages) from [<c0267ee8>] (do_writepages+0x3c/0xd4)
 (do_writepages) from [<c0310cbc>] (__writeback_single_inode+0x44/0x454)
 (__writeback_single_inode) from [<c03112d0>] (writeback_sb_inodes+0x204/0x4b0)
 (writeback_sb_inodes) from [<c03115cc>] (__writeback_inodes_wb+0x50/0xe4)
 (__writeback_inodes_wb) from [<c03118f4>] (wb_writeback+0x294/0x338)
 (wb_writeback) from [<c0312dac>] (wb_workfn+0x35c/0x54c)
 (wb_workfn) from [<c014f2b8>] (process_one_work+0x214/0x544)
 (process_one_work) from [<c014f634>] (worker_thread+0x4c/0x574)
 (worker_thread) from [<c01564fc>] (kthread+0x144/0x170)
 (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)

Reported-and-tested-by: Ondřej Jirman <megi@xff.cz>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-03-10 09:18:32 -07:00
Chao Yu
df77fbd8c5 f2fs: fix to avoid potential deadlock
Using f2fs_trylock_op() in f2fs_write_compressed_pages() to avoid potential
deadlock like we did in f2fs_write_single_data_page().

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-02-27 10:16:45 -08:00
Chao Yu
0b32dc1864 f2fs: recycle unused compress_data.chksum feild
In Struct compress_data, chksum field was never used, remove it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-02-27 10:16:45 -08:00
Chao Yu
61fbae2b2b f2fs: fix to avoid NULL pointer dereference
Unable to handle kernel NULL pointer dereference at virtual address 00000000
PC is at f2fs_free_dic+0x60/0x2c8
LR is at f2fs_decompress_pages+0x3c4/0x3e8
f2fs_free_dic+0x60/0x2c8
f2fs_decompress_pages+0x3c4/0x3e8
__read_end_io+0x78/0x19c
f2fs_post_read_work+0x6c/0x94
process_one_work+0x210/0x48c
worker_thread+0x2e8/0x44c
kthread+0x110/0x120
ret_from_fork+0x10/0x18

In f2fs_free_dic(), we can not use f2fs_put_page(,1) to release dic->tpages[i],
as the page's mapping is NULL.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-02-27 10:16:45 -08:00
Eric Biggers
7fa6d59816 f2fs: fix leaking uninitialized memory in compressed clusters
When the compressed data of a cluster doesn't end on a page boundary,
the remainder of the last page must be zeroed in order to avoid leaking
uninitialized memory to disk.

Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-02-27 10:16:44 -08:00
Chao Yu
4c8ff7095b f2fs: support data compression
This patch tries to support compression in f2fs.

- New term named cluster is defined as basic unit of compression, file can
be divided into multiple clusters logically. One cluster includes 4 << n
(n >= 0) logical pages, compression size is also cluster size, each of
cluster can be compressed or not.

- In cluster metadata layout, one special flag is used to indicate cluster
is compressed one or normal one, for compressed cluster, following metadata
maps cluster to [1, 4 << n - 1] physical blocks, in where f2fs stores
data including compress header and compressed data.

- In order to eliminate write amplification during overwrite, F2FS only
support compression on write-once file, data can be compressed only when
all logical blocks in file are valid and cluster compress ratio is lower
than specified threshold.

- To enable compression on regular inode, there are three ways:
* chattr +c file
* chattr +c dir; touch dir/file
* mount w/ -o compress_extension=ext; touch file.ext

Compress metadata layout:
                             [Dnode Structure]
             +-----------------------------------------------+
             | cluster 1 | cluster 2 | ......... | cluster N |
             +-----------------------------------------------+
             .           .                       .           .
       .                       .                .                      .
  .         Compressed Cluster       .        .        Normal Cluster            .
+----------+---------+---------+---------+  +---------+---------+---------+---------+
|compr flag| block 1 | block 2 | block 3 |  | block 1 | block 2 | block 3 | block 4 |
+----------+---------+---------+---------+  +---------+---------+---------+---------+
           .                             .
         .                                           .
       .                                                           .
      +-------------+-------------+----------+----------------------------+
      | data length | data chksum | reserved |      compressed data       |
      +-------------+-------------+----------+----------------------------+

Changelog:

20190326:
- fix error handling of read_end_io().
- remove unneeded comments in f2fs_encrypt_one_page().

20190327:
- fix wrong use of f2fs_cluster_is_full() in f2fs_mpage_readpages().
- don't jump into loop directly to avoid uninitialized variables.
- add TODO tag in error path of f2fs_write_cache_pages().

20190328:
- fix wrong merge condition in f2fs_read_multi_pages().
- check compressed file in f2fs_post_read_required().

20190401
- allow overwrite on non-compressed cluster.
- check cluster meta before writing compressed data.

20190402
- don't preallocate blocks for compressed file.

- add lz4 compress algorithm
- process multiple post read works in one workqueue
  Now f2fs supports processing post read work in multiple workqueue,
  it shows low performance due to schedule overhead of multiple
  workqueue executing orderly.

20190921
- compress: support buffered overwrite
C: compress cluster flag
V: valid block address
N: NEW_ADDR

One cluster contain 4 blocks

 before overwrite   after overwrite

- VVVV		->	CVNN
- CVNN		->	VVVV

- CVNN		->	CVNN
- CVNN		->	CVVV

- CVVV		->	CVNN
- CVVV		->	CVVV

20191029
- add kconfig F2FS_FS_COMPRESSION to isolate compression related
codes, add kconfig F2FS_FS_{LZO,LZ4} to cover backend algorithm.
note that: will remove lzo backend if Jaegeuk agreed that too.
- update codes according to Eric's comments.

20191101
- apply fixes from Jaegeuk

20191113
- apply fixes from Jaegeuk
- split workqueue for fsverity

20191216
- apply fixes from Jaegeuk

20200117
- fix to avoid NULL pointer dereference

[Jaegeuk Kim]
- add tracepoint for f2fs_{,de}compress_pages()
- fix many bugs and add some compression stats
- fix overwrite/mmap bugs
- address 32bit build error, reported by Geert.
- bug fixes when handling errors and i_compressed_blocks

Reported-by: <noreply@ellerman.id.au>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-01-17 16:48:07 -08:00