Commit graph

72 commits

Author SHA1 Message Date
Christoph Hellwig
e41d12f539 mm: don't include <linux/blk-cgroup.h> in <linux/backing-dev.h>
There is no need to pull blk-cgroup.h and thus blkdev.h in here, so
break the include chain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:01 -06:00
Jaegeuk Kim
827f02842e f2fs: deallocate compressed pages when error happens
In f2fs_write_multi_pages(), f2fs_compress_pages() allocates pages for
compression work in cc->cpages[]. Then, f2fs_write_compressed_pages() initiates
bio submission. But, if there's any error before submitting the IOs like early
f2fs_cp_error(), previously it didn't free cpages by f2fs_compress_free_page().
Let's fix memory leak by putting that just before deallocating cc->cpages.

Fixes: 4c8ff7095b ("f2fs: support data compression")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-08-31 14:39:24 -07:00
Chao Yu
bbe1da7e34 f2fs: compress: do sanity check on cluster
This patch adds f2fs_sanity_check_cluster() to support doing
sanity check on cluster of compressed file, it will be triggered
from below two paths:

- __f2fs_cluster_blocks()
- f2fs_map_blocks(F2FS_GET_BLOCK_FIEMAP)

And it can detect below three kind of cluster insanity status.

C: COMPRESS_ADDR
N: NULL_ADDR or NEW_ADDR
V: valid blkaddr
*: any value

1. [*|C|*|*]
2. [C|*|C|*]
3. [C|N|N|V]

Signed-off-by: Chao Yu <chao@kernel.org>
[Nathan Chancellor: fix missing inline warning]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-08-17 11:59:06 -07:00
Chao Yu
324105775c f2fs: support fault injection for f2fs_kmem_cache_alloc()
This patch supports to inject fault into f2fs_kmem_cache_alloc().

Usage:
a) echo 32768 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=32768 <dev> <mountpoint>

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-08-17 11:59:05 -07:00
Chao Yu
94afd6d6e5 f2fs: extent cache: support unaligned extent
Compressed inode may suffer read performance issue due to it can not
use extent cache, so I propose to add this unaligned extent support
to improve it.

Currently, it only works in readonly format f2fs image.

Unaligned extent: in one compressed cluster, physical block number
will be less than logical block number, so we add an extra physical
block length in extent info in order to indicate such extent status.

The idea is if one whole cluster blocks are contiguous physically,
once its mapping info was readed at first time, we will cache an
unaligned (or aligned) extent info entry in extent cache, it expects
that the mapping info will be hitted when rereading cluster.

Merge policy:
- Aligned extents can be merged.
- Aligned extent and unaligned extent can not be merged.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-08-05 11:26:11 -07:00
Chao Yu
6ce19aff0b f2fs: compress: add compress_inode to cache compressed blocks
Support to use address space of inner inode to cache compressed block,
in order to improve cache hit ratio of random read.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-06-23 01:09:35 -07:00
Jaegeuk Kim
c61404153e f2fs: introduce FI_COMPRESS_RELEASED instead of using IMMUTABLE bit
Once we release compressed blocks, we used to set IMMUTABLE bit. But it turned
out it disallows every fs operations which we don't need for compression.

Let's just prevent writing data only.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-06-23 01:09:34 -07:00
Chao Yu
8f1d498326 f2fs: compress: remove unneeded preallocation
We will reserve iblocks for compression saved, so during compressed
cluster overwrite, we don't need to preallocate blocks for later
write.

In addition, it adds a bug_on to detect wrong reserved iblock number
in __f2fs_cluster_blocks().

Bug fix in the original patch by Jaegeuk:
If we released compressed blocks having an immutable bit, we can see less
number of compressed block addresses. Let's fix wrong BUG_ON.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-06-23 01:09:33 -07:00
Jaegeuk Kim
e3c548323d f2fs: let's allow compression for mmap files
This patch allows to compress mmap files. E.g., for so files.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-05-26 07:00:36 -07:00
Chao Yu
91f0fb6903 f2fs: compress: clean up parameter of __f2fs_cluster_blocks()
Previously, in order to reuse __f2fs_cluster_blocks(),
f2fs_is_compressed_cluster() assigned a compress_ctx type variable,
which is used to pass few parameters (cc.inode, cc.cluster_size,
cc.cluster_idx), it's wasteful to allocate such large space in stack.

Let's clean up parameters of __f2fs_cluster_blocks() to avoid that.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-05-14 11:22:09 -07:00
Chao Yu
b763f3bedc f2fs: restructure f2fs page.private layout
Restruct f2fs page private layout for below reasons:

There are some cases that f2fs wants to set a flag in a page to
indicate a specified status of page:
a) page is in transaction list for atomic write
b) page contains dummy data for aligned write
c) page is migrating for GC
d) page contains inline data for inline inode flush
e) page belongs to merkle tree, and is verified for fsverity
f) page is dirty and has filesystem/inode reference count for writeback
g) page is temporary and has decompress io context reference for compression

There are existed places in page structure we can use to store
f2fs private status/data:
- page.flags: PG_checked, PG_private
- page.private

However it was a mess when we using them, which may cause potential
confliction:
		page.private	PG_private	PG_checked	page._refcount (+1 at most)
a)		-1		set				+1
b)		-2		set
c), d), e)					set
f)		0		set				+1
g)		pointer		set

The other problem is page.flags has no free slot, if we can avoid set
zero to page.private and set PG_private flag, then we use non-zero value
to indicate PG_private status, so that we may have chance to reclaim
PG_private slot for other usage. [1]

The other concern is f2fs has bad scalability in aspect of indicating
more page status.

So in this patch, let's restructure f2fs' page.private as below to
solve above issues:

Layout A: lowest bit should be 1
| bit0 = 1 | bit1 | bit2 | ... | bit MAX | private data .... |
 bit 0	PAGE_PRIVATE_NOT_POINTER
 bit 1	PAGE_PRIVATE_ATOMIC_WRITE
 bit 2	PAGE_PRIVATE_DUMMY_WRITE
 bit 3	PAGE_PRIVATE_ONGOING_MIGRATION
 bit 4	PAGE_PRIVATE_INLINE_INODE
 bit 5	PAGE_PRIVATE_REF_RESOURCE
 bit 6-	f2fs private data

Layout B: lowest bit should be 0
 page.private is a wrapped pointer.

After the change:
		page.private	PG_private	PG_checked	page._refcount (+1 at most)
a)		11		set				+1
b)		101		set				+1
c)		1001		set				+1
d)		10001		set				+1
e)						set
f)		100001		set				+1
g)		pointer		set				+1

[1] https://lore.kernel.org/linux-f2fs-devel/20210422154705.GO3596236@casper.infradead.org/T/#u

Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-05-14 11:22:08 -07:00
Chao Yu
ee68d27181 f2fs: add cp_error check in f2fs_write_compressed_pages
This patch adds cp_error check in f2fs_write_compressed_pages() 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>
2021-05-14 11:22:07 -07:00
Chao Yu
5db479f049 f2fs: compress: rename __cluster_may_compress
This patch renames __cluster_may_compress() to cluster_has_invalid_data() for
better readability.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-05-14 11:22:07 -07:00
Chao Yu
8bfbfb0ddd f2fs: compress: fix to assign cc.cluster_idx correctly
In f2fs_destroy_compress_ctx(), after f2fs_destroy_compress_ctx(),
cc.cluster_idx will be cleared w/ NULL_CLUSTER, f2fs_cluster_blocks()
may check wrong cluster metadata, fix it.

Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-05-11 14:48:12 -07:00
Chao Yu
a949dc5f2c f2fs: compress: fix race condition of overwrite vs truncate
pos_fsstress testcase complains a panic as belew:

------------[ cut here ]------------
kernel BUG at fs/f2fs/compress.c:1082!
invalid opcode: 0000 [#1] SMP PTI
CPU: 4 PID: 2753477 Comm: kworker/u16:2 Tainted: G           OE     5.12.0-rc1-custom #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Workqueue: writeback wb_workfn (flush-252:16)
RIP: 0010:prepare_compress_overwrite+0x4c0/0x760 [f2fs]
Call Trace:
 f2fs_prepare_compress_overwrite+0x5f/0x80 [f2fs]
 f2fs_write_cache_pages+0x468/0x8a0 [f2fs]
 f2fs_write_data_pages+0x2a4/0x2f0 [f2fs]
 do_writepages+0x38/0xc0
 __writeback_single_inode+0x44/0x2a0
 writeback_sb_inodes+0x223/0x4d0
 __writeback_inodes_wb+0x56/0xf0
 wb_writeback+0x1dd/0x290
 wb_workfn+0x309/0x500
 process_one_work+0x220/0x3c0
 worker_thread+0x53/0x420
 kthread+0x12f/0x150
 ret_from_fork+0x22/0x30

The root cause is truncate() may race with overwrite as below,
so that one reference count left in page can not guarantee the
page attaching in mapping tree all the time, after truncation,
later find_lock_page() may return NULL pointer.

- prepare_compress_overwrite
 - f2fs_pagecache_get_page
 - unlock_page
					- f2fs_setattr
					 - truncate_setsize
					  - truncate_inode_page
					   - delete_from_page_cache
 - find_lock_page

Fix this by avoiding referencing updated page.

Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-05-11 14:48:12 -07:00
Chao Yu
a12cc5b423 f2fs: compress: fix to free compress page correctly
In error path of f2fs_write_compressed_pages(), it needs to call
f2fs_compress_free_page() to release temporary page.

Fixes: 5e6bbde959 ("f2fs: introduce mempool for {,de}compress intermediate page allocation")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-05-11 14:48:12 -07:00
Chao Yu
8af85f712f f2fs: compress: remove unneed check condition
In only call path of __cluster_may_compress(), __f2fs_write_data_pages()
has checked SBI_POR_DOING condition, and also cluster_may_compress()
has checked CP_ERROR_FLAG condition, so remove redundant check condition
in __cluster_may_compress() for cleanup.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-04-26 09:50:36 -07:00
Chao Yu
2e22d48dca f2fs: clean up left deprecated IO trace codes
Commit d5f7bc0064 ("f2fs: deprecate f2fs_trace_io") left some
dead codes, delete them.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-04-24 17:41:50 -07:00
Daeho Jeong
5ac443e26a f2fs: add sysfs nodes to get runtime compression stat
I've added new sysfs nodes to show runtime compression stat since mount.
compr_written_block - show the block count written after compression
compr_saved_block - show the saved block count with compression
compr_new_inode - show the count of inode newly enabled for compression

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-03-25 18:20:50 -07:00
Chao Yu
3afae09ffe f2fs: compress: fix potential deadlock
generic/269 reports a hangtask issue, the root cause is ABBA deadlock
described as below:

Thread A			Thread B
- down_write(&sbi->gc_lock) -- A
				- f2fs_write_data_pages
				 - lock all pages in cluster -- B
				 - f2fs_write_multi_pages
				  - f2fs_write_raw_pages
				   - f2fs_write_single_data_page
				    - f2fs_balance_fs
				     - down_write(&sbi->gc_lock) -- A
- f2fs_gc
 - do_garbage_collect
  - ra_data_block
   - pagecache_get_page -- B

To fix this, it needs to avoid calling f2fs_balance_fs() if there is
still cluster pages been locked in context of cluster writeback, so
instead, let's call f2fs_balance_fs() in the end of
f2fs_write_raw_pages() when all cluster pages were unlocked.

Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-01-27 15:20:05 -08:00
Eric Biggers
7f59b277f7 f2fs: clean up post-read processing
Rework the post-read processing logic to be much easier to understand.

At least one bug is fixed by this: if an I/O error occurred when reading
from disk, decryption and verity would be performed on the uninitialized
data, causing misleading messages in the kernel log.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-01-27 15:20:04 -08:00
Chao Yu
3fde13f817 f2fs: compress: support compress level
Expand 'compress_algorithm' mount option to accept parameter as format of
<algorithm>:<level>, by this way, it gives a way to allow user to do more
specified config on lz4 and zstd compression level, then f2fs compression
can provide higher compress ratio.

In order to set compress level for lz4 algorithm, it needs to set
CONFIG_LZ4HC_COMPRESS and CONFIG_F2FS_FS_LZ4HC config to enable lz4hc
compress algorithm.

CR and performance number on lz4/lz4hc algorithm:

dd if=enwik9 of=compressed_file conv=fsync

Original blocks:	244382

			lz4			lz4hc-9
compressed blocks	170647			163270
compress ratio		69.8%			66.8%
speed			16.4207 s, 60.9 MB/s	26.7299 s, 37.4 MB/s

compress ratio = after / before

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-01-27 15:20:02 -08:00
Chao Yu
75e91c8889 f2fs: compress: fix compression chksum
This patch addresses minor issues in compression chksum.

Fixes: b28f047b28 ("f2fs: compress: support chksum")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-12-10 09:13:53 -08:00
Daeho Jeong
6422a71ef4 f2fs: fix race of pending_pages in decompression
I found out f2fs_free_dic() is invoked in a wrong timing, but
f2fs_verify_bio() still needed the dic info and it triggered the
below kernel panic. It has been caused by the race condition of
pending_pages value between decompression and verity logic, when
the same compression cluster had been split in different bios.
By split bios, f2fs_verify_bio() ended up with decreasing
pending_pages value before it is reset to nr_cpages by
f2fs_decompress_pages() and caused the kernel panic.

[ 4416.564763] Unable to handle kernel NULL pointer dereference
               at virtual address 0000000000000000
...
[ 4416.896016] Workqueue: fsverity_read_queue f2fs_verity_work
[ 4416.908515] pc : fsverity_verify_page+0x20/0x78
[ 4416.913721] lr : f2fs_verify_bio+0x11c/0x29c
[ 4416.913722] sp : ffffffc019533cd0
[ 4416.913723] x29: ffffffc019533cd0 x28: 0000000000000402
[ 4416.913724] x27: 0000000000000001 x26: 0000000000000100
[ 4416.913726] x25: 0000000000000001 x24: 0000000000000004
[ 4416.913727] x23: 0000000000001000 x22: 0000000000000000
[ 4416.913728] x21: 0000000000000000 x20: ffffffff2076f9c0
[ 4416.913729] x19: ffffffff2076f9c0 x18: ffffff8a32380c30
[ 4416.913731] x17: ffffffc01f966d97 x16: 0000000000000298
[ 4416.913732] x15: 0000000000000000 x14: 0000000000000000
[ 4416.913733] x13: f074faec89ffffff x12: 0000000000000000
[ 4416.913734] x11: 0000000000001000 x10: 0000000000001000
[ 4416.929176] x9 : ffffffff20d1f5c7 x8 : 0000000000000000
[ 4416.929178] x7 : 626d7464ff286b6b x6 : ffffffc019533ade
[ 4416.929179] x5 : 000000008049000e x4 : ffffffff2793e9e0
[ 4416.929180] x3 : 000000008049000e x2 : ffffff89ecfa74d0
[ 4416.929181] x1 : 0000000000000c40 x0 : ffffffff2076f9c0
[ 4416.929184] Call trace:
[ 4416.929187]  fsverity_verify_page+0x20/0x78
[ 4416.929189]  f2fs_verify_bio+0x11c/0x29c
[ 4416.929192]  f2fs_verity_work+0x58/0x84
[ 4417.050667]  process_one_work+0x270/0x47c
[ 4417.055354]  worker_thread+0x27c/0x4d8
[ 4417.059784]  kthread+0x13c/0x320
[ 4417.063693]  ret_from_fork+0x10/0x18

Chao pointed this can happen by the below race condition.

Thread A        f2fs_post_read_wq          fsverity_wq
- f2fs_read_multi_pages()
  - f2fs_alloc_dic
   - dic->pending_pages = 2
   - submit_bio()
   - submit_bio()
               - f2fs_post_read_work() handle first bio
                - f2fs_decompress_work()
                 - __read_end_io()
                  - f2fs_decompress_pages()
                   - dic->pending_pages--
                - enqueue f2fs_verity_work()
                                           - f2fs_verity_work() handle first bio
                                            - f2fs_verify_bio()
                                             - dic->pending_pages--
               - f2fs_post_read_work() handle second bio
                - f2fs_decompress_work()
                - enqueue f2fs_verity_work()
                                            - f2fs_verify_pages()
                                            - f2fs_free_dic()

                                          - f2fs_verity_work() handle second bio
                                           - f2fs_verfy_bio()
                                                 - use-after-free on dic

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-12-08 15:39:14 -08:00
Daeho Jeong
602a16d58e f2fs: add compress_mode mount option
We will add a new "compress_mode" mount option to control file
compression mode. This supports "fs" and "user". In "fs" mode (default),
f2fs does automatic compression on the compression enabled files.
In "user" mode, f2fs disables the automaic compression and gives the
user discretion of choosing the target file and the timing. It means
the user can do manual compression/decompression on the compression
enabled files using ioctls.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-12-03 00:11:57 -08:00
Chao Yu
b28f047b28 f2fs: compress: support chksum
This patch supports to store chksum value with compressed
data, and verify the integrality of compressed data while
reading the data.

The feature can be enabled through specifying mount option
'compress_chksum'.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-12-02 22:00:22 -08:00
Jaegeuk Kim
adfc694330 f2fs: fix slab leak of rpages pointer
This fixes the below mem leak.

[  130.157600] =============================================================================
[  130.159662] BUG f2fs_page_array_entry-252:16 (Tainted: G        W  O     ): Objects remaining in f2fs_page_array_entry-252:16 on __kmem_cache_shutdown()
[  130.162742] -----------------------------------------------------------------------------
[  130.162742]
[  130.164979] Disabling lock debugging due to kernel taint
[  130.166188] INFO: Slab 0x000000009f5a52d2 objects=22 used=4 fp=0x00000000ba72c3e9 flags=0xfffffc0010200
[  130.168269] CPU: 7 PID: 3560 Comm: umount Tainted: G    B   W  O      5.9.0-rc4+ #35
[  130.170019] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014
[  130.171941] Call Trace:
[  130.172528]  dump_stack+0x74/0x9a
[  130.173298]  slab_err+0xb7/0xdc
[  130.174044]  ? kernel_poison_pages+0xc0/0xc0
[  130.175065]  ? on_each_cpu_cond_mask+0x48/0x90
[  130.176096]  __kmem_cache_shutdown.cold+0x34/0x141
[  130.177190]  kmem_cache_destroy+0x59/0x100
[  130.178223]  f2fs_destroy_page_array_cache+0x15/0x20 [f2fs]
[  130.179527]  f2fs_put_super+0x1bc/0x380 [f2fs]
[  130.180538]  generic_shutdown_super+0x72/0x110
[  130.181547]  kill_block_super+0x27/0x50
[  130.182438]  kill_f2fs_super+0x76/0xe0 [f2fs]
[  130.183448]  deactivate_locked_super+0x3b/0x80
[  130.184456]  deactivate_super+0x3e/0x50
[  130.185363]  cleanup_mnt+0x109/0x160
[  130.186179]  __cleanup_mnt+0x12/0x20
[  130.187003]  task_work_run+0x70/0xb0
[  130.187841]  exit_to_user_mode_prepare+0x18f/0x1b0
[  130.188917]  syscall_exit_to_user_mode+0x31/0x170
[  130.189989]  do_syscall_64+0x45/0x90
[  130.190828]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  130.191986] RIP: 0033:0x7faf868ea2eb
[  130.192815] Code: 7b 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 90 f3 0f 1e fa 31 f6 e9 05 00 00 00 0f 1f 44 00 00 f3 0f 1e fa b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 75 7b 0c 00 f7 d8 64 89 01
[  130.196872] RSP: 002b:00007fffb7edb478 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[  130.198494] RAX: 0000000000000000 RBX: 00007faf86a18204 RCX: 00007faf868ea2eb
[  130.201021] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055971df71c50
[  130.203415] RBP: 000055971df71a40 R08: 0000000000000000 R09: 00007fffb7eda1f0
[  130.205772] R10: 00007faf86a04339 R11: 0000000000000246 R12: 000055971df71c50
[  130.208150] R13: 0000000000000000 R14: 000055971df71b38 R15: 0000000000000000
[  130.210515] INFO: Object 0x00000000a980843a @offset=744
[  130.212476] INFO: Allocated in page_array_alloc+0x3d/0xe0 [f2fs] age=1572 cpu=0 pid=3297
[  130.215030] 	__slab_alloc+0x20/0x40
[  130.216566] 	kmem_cache_alloc+0x2a0/0x2e0
[  130.218217] 	page_array_alloc+0x3d/0xe0 [f2fs]
[  130.219940] 	f2fs_init_compress_ctx+0x1f/0x40 [f2fs]
[  130.221736] 	f2fs_write_cache_pages+0x3db/0x860 [f2fs]
[  130.223591] 	f2fs_write_data_pages+0x2c9/0x300 [f2fs]
[  130.225414] 	do_writepages+0x43/0xd0
[  130.226907] 	__filemap_fdatawrite_range+0xd5/0x110
[  130.228632] 	filemap_write_and_wait_range+0x48/0xb0
[  130.230336] 	__generic_file_write_iter+0x18a/0x1d0
[  130.232035] 	f2fs_file_write_iter+0x226/0x550 [f2fs]
[  130.233737] 	new_sync_write+0x113/0x1a0
[  130.235204] 	vfs_write+0x1a6/0x200
[  130.236579] 	ksys_write+0x67/0xe0
[  130.237898] 	__x64_sys_write+0x1a/0x20
[  130.239309] 	do_syscall_64+0x38/0x90

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-29 09:16:36 -07:00
Chao Yu
c68d6c8830 f2fs: compress: introduce cic/dic slab cache
Add two slab caches: "f2fs_cic_entry" and "f2fs_dic_entry" for memory
allocation of compress_io_ctx and decompress_io_ctx structure.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-29 09:16:36 -07:00
Chao Yu
3108303170 f2fs: compress: introduce page array slab cache
Add a per-sbi slab cache "f2fs_page_array_entry-%u:%u" for memory
allocation of page pointer array in compress context.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: Fix wrong memory allocation]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-29 09:16:32 -07:00
Daeho Jeong
6fcaebac66 f2fs: change virtual mapping way for compression pages
By profiling f2fs compression works, I've found vmap() callings have
unexpected hikes in the execution time in our test environment and
those are bottlenecks of f2fs decompression path. Changing these with
vm_map_ram(), we can enhance f2fs decompression speed pretty much.

[Verification]
Android Pixel 3(ARM64, 6GB RAM, 128GB UFS)
Turned on only 0-3 little cores(at 1.785GHz)

dd if=/dev/zero of=dummy bs=1m count=1000
echo 3 > /proc/sys/vm/drop_caches
dd if=dummy of=/dev/zero bs=512k

- w/o compression -
1048576000 bytes (0.9 G) copied, 2.082554 s, 480 M/s
1048576000 bytes (0.9 G) copied, 2.081634 s, 480 M/s
1048576000 bytes (0.9 G) copied, 2.090861 s, 478 M/s

- before patch -
1048576000 bytes (0.9 G) copied, 7.407527 s, 135 M/s
1048576000 bytes (0.9 G) copied, 7.283734 s, 137 M/s
1048576000 bytes (0.9 G) copied, 7.291508 s, 137 M/s

- after patch -
1048576000 bytes (0.9 G) copied, 1.998959 s, 500 M/s
1048576000 bytes (0.9 G) copied, 1.987554 s, 503 M/s
1048576000 bytes (0.9 G) copied, 1.986380 s, 503 M/s

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-11 11:11:26 -07:00
Chao Yu
0e2b7385cb f2fs: allocate proper size memory for zstd decompress
As 5kft <5kft@5kft.org> reported:

 kworker/u9:3: page allocation failure: order:9, mode:0x40c40(GFP_NOFS|__GFP_COMP), nodemask=(null),cpuset=/,mems_allowed=0
 CPU: 3 PID: 8168 Comm: kworker/u9:3 Tainted: G         C        5.8.3-sunxi #trunk
 Hardware name: Allwinner sun8i Family
 Workqueue: f2fs_post_read_wq f2fs_post_read_work
 [<c010d6d5>] (unwind_backtrace) from [<c0109a55>] (show_stack+0x11/0x14)
 [<c0109a55>] (show_stack) from [<c056d489>] (dump_stack+0x75/0x84)
 [<c056d489>] (dump_stack) from [<c0243b53>] (warn_alloc+0xa3/0x104)
 [<c0243b53>] (warn_alloc) from [<c024473b>] (__alloc_pages_nodemask+0xb87/0xc40)
 [<c024473b>] (__alloc_pages_nodemask) from [<c02267c5>] (kmalloc_order+0x19/0x38)
 [<c02267c5>] (kmalloc_order) from [<c02267fd>] (kmalloc_order_trace+0x19/0x90)
 [<c02267fd>] (kmalloc_order_trace) from [<c047c665>] (zstd_init_decompress_ctx+0x21/0x88)
 [<c047c665>] (zstd_init_decompress_ctx) from [<c047e9cf>] (f2fs_decompress_pages+0x97/0x228)
 [<c047e9cf>] (f2fs_decompress_pages) from [<c045d0ab>] (__read_end_io+0xfb/0x130)
 [<c045d0ab>] (__read_end_io) from [<c045d141>] (f2fs_post_read_work+0x61/0x84)
 [<c045d141>] (f2fs_post_read_work) from [<c0130b2f>] (process_one_work+0x15f/0x3b0)
 [<c0130b2f>] (process_one_work) from [<c0130e7b>] (worker_thread+0xfb/0x3e0)
 [<c0130e7b>] (worker_thread) from [<c0135c3b>] (kthread+0xeb/0x10c)
 [<c0135c3b>] (kthread) from [<c0100159>]

zstd may allocate large size memory for {,de}compression, it may cause
file copy failure on low-end device which has very few memory.

For decompression, let's just allocate proper size memory based on current
file's cluster size instead of max cluster size.

Reported-by: 5kft <5kft@5kft.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-11 11:11:25 -07:00
Chao Yu
e6c3948de2 f2fs: compress: use more readable atomic_t type for {cic,dic}.ref
refcount_t type variable should never be less than one, so it's a
little bit hard to understand when we use it to indicate pending
compressed page count, let's change to use atomic_t for better
readability.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-10 14:03:31 -07:00
Chao Yu
376207af4b f2fs: compress: remove unneeded code
- f2fs_write_multi_pages
 - f2fs_compress_pages
  - init_compress_ctx
  - compress_pages
  - destroy_compress_ctx  --- 1
 - f2fs_write_compressed_pages
 - destroy_compress_ctx  --- 2

destroy_compress_ctx() in f2fs_write_multi_pages() is redundant, remove
it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-10 14:03:30 -07:00
Linus Torvalds
086ba2ec16 f2fs-for-5.9-rc1
In this round, we've added two small interfaces, 1) GC_URGENT_LOW mode for
 performance, and 2) F2FS_IOC_SEC_TRIM_FILE ioctl for security. The new GC
 mode allows Android to run some lower priority GCs in background, while new
 ioctl discards user information without race condition when the account is
 removed. In addition, some patches were merged to address latency-related
 issues. We've fixed some compression-related bug fixes as well as edge race
 conditions.
 
 Enhancement:
  - add GC_URGENT_LOW mode in gc_urgent
  - introduce F2FS_IOC_SEC_TRIM_FILE ioctl
  - bypass racy readahead to improve read latencies
  - shrink node_write lock coverage to avoid long latency
 
 Bug fix:
  - fix missing compression flag control, i_size, and mount option
  - fix deadlock between quota writes and checkpoint
  - remove inode eviction path in synchronous path to avoid deadlock
  - fix to wait GCed compressed page writeback
  - fix a kernel panic in f2fs_is_compressed_page
  - check page dirty status before writeback
  - wait page writeback before update in node page write flow
  - fix a race condition between f2fs_write_end_io and f2fs_del_fsync_node_entry
 
 We've added some minor sanity checks and refactored trivial code blocks for
 better readability and debugging information.
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Merge tag 'f2fs-for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've added two small interfaces: (a) GC_URGENT_LOW
  mode for performance and (b) F2FS_IOC_SEC_TRIM_FILE ioctl for
  security.

  The new GC mode allows Android to run some lower priority GCs in
  background, while new ioctl discards user information without race
  condition when the account is removed.

  In addition, some patches were merged to address latency-related
  issues. We've fixed some compression-related bug fixes as well as edge
  race conditions.

  Enhancements:
   - add GC_URGENT_LOW mode in gc_urgent
   - introduce F2FS_IOC_SEC_TRIM_FILE ioctl
   - bypass racy readahead to improve read latencies
   - shrink node_write lock coverage to avoid long latency

  Bug fixes:
   - fix missing compression flag control, i_size, and mount option
   - fix deadlock between quota writes and checkpoint
   - remove inode eviction path in synchronous path to avoid deadlock
   - fix to wait GCed compressed page writeback
   - fix a kernel panic in f2fs_is_compressed_page
   - check page dirty status before writeback
   - wait page writeback before update in node page write flow
   - fix a race condition between f2fs_write_end_io and f2fs_del_fsync_node_entry

  We've added some minor sanity checks and refactored trivial code
  blocks for better readability and debugging information"

* tag 'f2fs-for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (52 commits)
  f2fs: prepare a waiter before entering io_schedule
  f2fs: update_sit_entry: Make the judgment condition of f2fs_bug_on more intuitive
  f2fs: replace test_and_set/clear_bit() with set/clear_bit()
  f2fs: make file immutable even if releasing zero compression block
  f2fs: compress: disable compression mount option if compression is off
  f2fs: compress: add sanity check during compressed cluster read
  f2fs: use macro instead of f2fs verity version
  f2fs: fix deadlock between quota writes and checkpoint
  f2fs: correct comment of f2fs_exist_written_data
  f2fs: compress: delay temp page allocation
  f2fs: compress: fix to update isize when overwriting compressed file
  f2fs: space related cleanup
  f2fs: fix use-after-free issue
  f2fs: Change the type of f2fs_flush_inline_data() to void
  f2fs: add F2FS_IOC_SEC_TRIM_FILE ioctl
  f2fs: should avoid inode eviction in synchronous path
  f2fs: segment.h: delete a duplicated word
  f2fs: compress: fix to avoid memory leak on cc->cpages
  f2fs: use generic names for generic ioctls
  f2fs: don't keep meta inode pages used for compressed block migration
  ...
2020-08-10 18:33:22 -07:00
Chao Yu
b2f57a8e6b f2fs: compress: delay temp page allocation
Currently, we allocate temp pages which is used to pad hole in
cluster during read IO submission, it may take long time before
releasing them in f2fs_decompress_pages(), since they are only
used as temp output buffer in decompression context, so let's
just do the allocation in that context to reduce time of memory
pool resource occupation.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-07-26 08:20:16 -07:00
Chao Yu
02772fbfcb f2fs: compress: fix to avoid memory leak on cc->cpages
Memory allocated for storing compressed pages' poitner should be
released after f2fs_write_compressed_pages(), otherwise it will
cause memory leak issue.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-07-20 15:47:38 -07:00
Satya Tangirala
27aacd28ea f2fs: add inline encryption support
Wire up f2fs to support inline encryption via the helper functions which
fs/crypto/ now provides.  This includes:

- Adding a mount option 'inlinecrypt' which enables inline encryption
  on encrypted files where it can be used.

- Setting the bio_crypt_ctx on bios that will be submitted to an
  inline-encrypted file.

- Not adding logically discontiguous data to bios that will be submitted
  to an inline-encrypted file.

- Not doing filesystem-layer crypto on inline-encrypted files.

This patch includes a fix for a race during IPU by
Sahitya Tummala <stummala@codeaurora.org>

Signed-off-by: Satya Tangirala <satyat@google.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20200702015607.1215430-4-satyat@google.com
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-07-08 10:29:43 -07:00
Chao Yu
f567adb034 f2fs: fix to wait GCed compressed page writeback
like we did for encrypted page.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-07-08 10:11:19 -07:00
Yu Changchun
29b993c7cd f2fs: fix an oops in f2fs_is_compressed_page
This patch is to fix a crash:

 #3 [ffffb6580689f898] oops_end at ffffffffa2835bc2
 #4 [ffffb6580689f8b8] no_context at ffffffffa28766e7
 #5 [ffffb6580689f920] async_page_fault at ffffffffa320135e
    [exception RIP: f2fs_is_compressed_page+34]
    RIP: ffffffffa2ba83a2  RSP: ffffb6580689f9d8  RFLAGS: 00010213
    RAX: 0000000000000001  RBX: fffffc0f50b34bc0  RCX: 0000000000002122
    RDX: 0000000000002123  RSI: 0000000000000c00  RDI: fffffc0f50b34bc0
    RBP: ffff97e815a40178   R8: 0000000000000000   R9: ffff97e83ffc9000
    R10: 0000000000032300  R11: 0000000000032380  R12: ffffb6580689fa38
    R13: fffffc0f50b34bc0  R14: ffff97e825cbd000  R15: 0000000000000c00
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #6 [ffffb6580689f9d8] __is_cp_guaranteed at ffffffffa2b7ea98
 #7 [ffffb6580689f9f0] f2fs_submit_page_write at ffffffffa2b81a69
 #8 [ffffb6580689fa30] f2fs_do_write_meta_page at ffffffffa2b99777
 #9 [ffffb6580689fae0] __f2fs_write_meta_page at ffffffffa2b75f1a
 #10 [ffffb6580689fb18] f2fs_sync_meta_pages at ffffffffa2b77466
 #11 [ffffb6580689fc98] do_checkpoint at ffffffffa2b78e46
 #12 [ffffb6580689fd88] f2fs_write_checkpoint at ffffffffa2b79c29
 #13 [ffffb6580689fdd0] f2fs_sync_fs at ffffffffa2b69d95
 #14 [ffffb6580689fe20] sync_filesystem at ffffffffa2ad2574
 #15 [ffffb6580689fe30] generic_shutdown_super at ffffffffa2a9b582
 #16 [ffffb6580689fe48] kill_block_super at ffffffffa2a9b6d1
 #17 [ffffb6580689fe60] kill_f2fs_super at ffffffffa2b6abe1
 #18 [ffffb6580689fea0] deactivate_locked_super at ffffffffa2a9afb6
 #19 [ffffb6580689feb8] cleanup_mnt at ffffffffa2abcad4
 #20 [ffffb6580689fee0] task_work_run at ffffffffa28bca28
 #21 [ffffb6580689ff00] exit_to_usermode_loop at ffffffffa28050b7
 #22 [ffffb6580689ff38] do_syscall_64 at ffffffffa280560e
 #23 [ffffb6580689ff50] entry_SYSCALL_64_after_hwframe at ffffffffa320008c

This occurred when umount f2fs if enable F2FS_FS_COMPRESSION
with F2FS_IO_TRACE. Fixes it by adding IS_IO_TRACED_PAGE to check
validity of pid for page_private.

Signed-off-by: Yu Changchun <yuchangchun1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-07-07 21:51:47 -07:00
Chao Yu
eb1353cfa9 f2fs: fix to check page dirty status before writeback
In f2fs_write_raw_pages(), we need to check page dirty status before
writeback, because there could be a racer (e.g. reclaimer) helps
writebacking the dirty page.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-07-07 21:51:47 -07:00
Wang Xiaojun
d078319d06 f2fs: remove the unused compr parameter
The parameter compr is unused in the f2fs_cluster_blocks function
so we no longer need to pass it as a parameter.

Signed-off-by: Wang Xiaojun <wangxiaojun11@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-07-07 21:51:46 -07:00
Chao Yu
79963d967b f2fs: shrink node_write lock coverage
- to avoid race between checkpoint and quota file writeback, it
just needs to hold read lock of node_write in writeback path.
- node_write lock has covered all LFS data write paths, it's not
necessary, we only need to hold node_write lock at write path of
quota file.

This refactors commit ca7f76e680 ("f2fs: fix wrong discard space").

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-07-07 21:51:44 -07:00
Chao Yu
0ef818335f f2fs: add prefix for exported symbols
to avoid polluting global symbol namespace.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-07-07 21:51:43 -07:00
Jaegeuk Kim
99bbe30701 f2fs: avoid checkpatch error
ERROR:INITIALISED_STATIC: do not initialise statics to NULL

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-06-18 12:33:11 -07:00
Chao Yu
bc67c5d0ce f2fs: remove unused parameter of f2fs_put_rpages_mapping()
Just cleanup, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-06-08 20:37:53 -07:00
Chao Yu
dc35d73a42 f2fs: compress: don't compress any datas after cp stop
While compressed data writeback, we need to drop dirty pages like we did
for non-compressed pages if cp stops, however it's not needed to compress
any data in such case, so let's detect cp stop condition in
cluster_may_compress() to avoid redundant compressing and let following
f2fs_write_raw_pages() drops dirty pages correctly.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-05-28 12:00:43 -07:00
Chao Yu
1454c978ef f2fs: compress: fix zstd data corruption
During zstd compression, ZSTD_endStream() may return non-zero value
because distination buffer is full, but there is still compressed data
remained in intermediate buffer, it means that zstd algorithm can not
save at last one block space, let's just writeback raw data instead of
compressed one, this can fix data corruption when decompressing
incomplete stored compression data.

Fixes: 50cfa66f0d ("f2fs: compress: support zstd compress algorithm")
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-05-11 20:37:13 -07:00
Chao Yu
f6644143c6 f2fs: compress: let lz4 compressor handle output buffer budget properly
Commonly, in order to handle lz4 worst compress case, caller should
allocate buffer with size of LZ4_compressBound(inputsize) for target
compressed data storing, however in this case, if caller didn't
allocate enough space, lz4 compressor still can handle output buffer
budget properly, and end up compressing when left space in output
buffer is not enough.

So we don't have to allocate buffer with size for worst case, then
we can avoid 2 * 4KB size intermediate buffer allocation when
log_cluster_size is 2, and avoid unnecessary compressing work of
compressor if we can not save at least 4KB space.

Suggested-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-05-11 20:36:47 -07:00
Chao Yu
6d92b20103 f2fs: compress: support lzo-rle compress algorithm
LZO-RLE extension (run length encoding) was introduced to improve
performance of LZO algorithm in scenario of data contains many zeros,
zram has changed to use this extended algorithm by default, this
patch adds to support this algorithm extension, to enable this
extension, it needs to enable F2FS_FS_LZO and F2FS_FS_LZORLE config,
and specifies "compress_algorithm=lzo-rle" mountoption.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-05-11 20:36:46 -07:00
Chao Yu
5e6bbde959 f2fs: introduce mempool for {,de}compress intermediate page allocation
If compression feature is on, in scenario of no enough free memory,
page refault ratio is higher than before, the root cause is:
- {,de}compression flow needs to allocate intermediate pages to store
compressed data in cluster, so during their allocation, vm may reclaim
mmaped pages.
- if above reclaimed pages belong to compressed cluster, during its
refault, it may cause more intermediate pages allocation, result in
reclaiming more mmaped pages.

So this patch introduces a mempool for intermediate page allocation,
in order to avoid high refault ratio, by default, number of
preallocated page in pool is 512, user can change the number by
assigning 'num_compress_pages' parameter during module initialization.

Ma Feng found warnings in the original patch and fixed like below.

Fix the following sparse warning:
fs/f2fs/compress.c:501:5: warning: symbol 'num_compress_pages' was not declared.
 Should it be static?
fs/f2fs/compress.c:530:6: warning: symbol 'f2fs_compress_free_page' was not
declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Ma Feng <mafeng.ma@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-05-11 20:35:51 -07:00