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Unfair rwsem should be used when blk-cg is on. Otherwise, there is regression.
FYI, we noticed a -26.7% regression of aim7.jobs-per-min due to commit:
commit: e4544b63a7 ("f2fs: move f2fs to use reader-unfair rwsems")
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master
in testcase: aim7
on test machine: 88 threads 2 sockets Intel(R) Xeon(R) Gold 6238M CPU @ 2.10GHz with 128G memory
with following parameters:
disk: 4BRD_12G
md: RAID0
fs: f2fs
test: sync_disk_rw
load: 100
cpufreq_governor: performance
ucode: 0x500320a
test-description: AIM7 is a traditional UNIX system level benchmark suite which is used to test and measure the performance of multiuser system.
test-url: https://sourceforge.net/projects/aimbench/files/aim-suite7/
Reported-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Implement 'struct iomap_ops' for f2fs, in preparation for making f2fs
use iomap for direct I/O.
Note that this may be used for other things besides direct I/O in the
future; however, for now I've only tested it for direct I/O.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Added F2FS_IOSTAT config option to support getting IO statistics through
sysfs and printing out periodic IO statistics tracepoint events and
moved I/O statistics related codes into separate files for better
maintenance.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
[Jaegeuk Kim: set default=y]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In fs/f2fs/Kconfig, F2FS_FS_LZ4HC depends on F2FS_FS_LZ4 and F2FS_FS_LZ4
depends on F2FS_FS_COMPRESSION, so no need to make F2FS_FS_LZ4HC depends
on F2FS_FS_COMPRESSION explicitly, remove the redudant "depends on", do
the similar thing for F2FS_FS_LZORLE.
At the same time, it is better to move F2FS_FS_LZORLE next to F2FS_FS_LZO,
it looks like a little more clear when make menuconfig, the location of
"LZO-RLE compression support" is under "LZO compression support" instead
of "F2FS compression feature".
Without this patch:
F2FS compression feature
LZO compression support
LZ4 compression support
LZ4HC compression support
ZSTD compression support
LZO-RLE compression support
With this patch:
F2FS compression feature
LZO compression support
LZO-RLE compression support
LZ4 compression support
LZ4HC compression support
ZSTD compression support
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If F2FS_FS is modular, enabling the compressions options
F2FS_FS_{LZ4,LZ4HZ,LZO,LZORLE,ZSTD} will make the (de)compression
algorithms {LZ4,LZ4HC,LZO,ZSTD}_{,DE}COMPRESS builtin instead of
modular, as the former depend on an intermediate boolean
F2FS_FS_COMPRESSION, which in-turn depends on tristate F2FS_FS.
Indeed, if a boolean symbol A depends directly on a tristate symbol B
and selects another tristate symbol C:
tristate B
tristate C
bool A
depends on B
select C
and B is modular, then C will also be modular.
However, if there is an intermediate boolean D in the dependency chain
between A and B:
tristate B
tristate C
bool D
depends on B
bool A
depends on D
select C
then the modular state won't propagate from B to C, and C will be
builtin instead of modular.
As modular dependency propagation through intermediate symbols is
obscure, fix this in a robust way by moving the selection of tristate
(de)compression algorithms from the boolean compression options to the
tristate main F2FS_FS option.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch deprecates f2fs_trace_io, since f2fs uses page->private more broadly,
resulting in more buggy cases.
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
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>
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>
In this series, we've implemented transparent compression experimentally. It
supports LZO and LZ4, but will add more later as we investigate in the field
more. At this point, the feature doesn't expose compressed space to user
directly in order to guarantee potential data updates later to the space.
Instead, the main goal is to reduce data writes to flash disk as much as
possible, resulting in extending disk life time as well as relaxing IO
congestion. Alternatively, we're also considering to add ioctl() to reclaim
compressed space and show it to user after putting the immutable bit.
Enhancement:
- add compression support
- avoid unnecessary locks in quota ops
- harden power-cut scenario for zoned block devices
- use private bio_set to avoid IO congestion
- replace GC mutex with rwsem to serialize callers
Bug fix:
- fix dentry consistency and memory corruption in rename()'s error case
- fix wrong swap extent reports
- fix casefolding bugs
- change lock coverage to avoid deadlock
- avoid GFP_KERNEL under f2fs_lock_op
And, we've cleaned up sysfs entries to prepare no debugfs.
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Merge tag 'f2fs-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this series, we've implemented transparent compression
experimentally. It supports LZO and LZ4, but will add more later as we
investigate in the field more.
At this point, the feature doesn't expose compressed space to user
directly in order to guarantee potential data updates later to the
space. Instead, the main goal is to reduce data writes to flash disk
as much as possible, resulting in extending disk life time as well as
relaxing IO congestion.
Alternatively, we're also considering to add ioctl() to reclaim
compressed space and show it to user after putting the immutable bit.
Enhancements:
- add compression support
- avoid unnecessary locks in quota ops
- harden power-cut scenario for zoned block devices
- use private bio_set to avoid IO congestion
- replace GC mutex with rwsem to serialize callers
Bug fixes:
- fix dentry consistency and memory corruption in rename()'s error case
- fix wrong swap extent reports
- fix casefolding bugs
- change lock coverage to avoid deadlock
- avoid GFP_KERNEL under f2fs_lock_op
And, we've cleaned up sysfs entries to prepare no debugfs"
* tag 'f2fs-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (31 commits)
f2fs: fix race conditions in ->d_compare() and ->d_hash()
f2fs: fix dcache lookup of !casefolded directories
f2fs: Add f2fs stats to sysfs
f2fs: delete duplicate information on sysfs nodes
f2fs: change to use rwsem for gc_mutex
f2fs: update f2fs document regarding to fsync_mode
f2fs: add a way to turn off ipu bio cache
f2fs: code cleanup for f2fs_statfs_project()
f2fs: fix miscounted block limit in f2fs_statfs_project()
f2fs: show the CP_PAUSE reason in checkpoint traces
f2fs: fix deadlock allocating bio_post_read_ctx from mempool
f2fs: remove unneeded check for error allocating bio_post_read_ctx
f2fs: convert inline_dir early before starting rename
f2fs: fix memleak of kobject
f2fs: fix to add swap extent correctly
f2fs: run fsck when getting bad inode during GC
f2fs: support data compression
f2fs: free sysfs kobject
f2fs: declare nested quota_sem and remove unnecessary sems
f2fs: don't put new_page twice in f2fs_rename
...
Currently f2fs stats are only available from /d/f2fs/status. This patch
adds some of the f2fs stats to sysfs so that they are accessible even
when debugfs is not mounted.
The following sysfs nodes are added:
-/sys/fs/f2fs/<disk>/free_segments
-/sys/fs/f2fs/<disk>/cp_foreground_calls
-/sys/fs/f2fs/<disk>/cp_background_calls
-/sys/fs/f2fs/<disk>/gc_foreground_calls
-/sys/fs/f2fs/<disk>/gc_background_calls
-/sys/fs/f2fs/<disk>/moved_blocks_foreground
-/sys/fs/f2fs/<disk>/moved_blocks_background
-/sys/fs/f2fs/<disk>/avg_vblocks
Signed-off-by: Hridya Valsaraju <hridya@google.com>
[Jaegeuk Kim: allow STAT_FS without DEBUG_FS]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
The commit 643fa9612b ("fscrypt: remove filesystem specific
build config option") removed modular support for fs/crypto. This
causes the Crypto API to be built-in whenever fscrypt is enabled.
This makes it very difficult for me to test modular builds of
the Crypto API without disabling fscrypt which is a pain.
As fscrypt is still evolving and it's developing new ties with the
fs layer, it's hard to build it as a module for now.
However, the actual algorithms are not required until a filesystem
is mounted. Therefore we can allow them to be built as modules.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Link: https://lore.kernel.org/r/20191227024700.7vrzuux32uyfdgum@gondor.apana.org.au
Signed-off-by: Eric Biggers <ebiggers@google.com>
If CONFIG_F2FS_FS=y but CONFIG_NLS=m, building fails:
fs/f2fs/file.o: In function `f2fs_ioctl':
file.c:(.text+0xb86f): undefined reference to `utf16s_to_utf8s'
file.c:(.text+0xe651): undefined reference to `utf8s_to_utf16s'
Select CONFIG_NLS to fix this.
Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 61a3da4d5ef8 ("f2fs: support FS_IOC_{GET,SET}FSLABEL")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to have a common code base for fscrypt "post read" processing
for all filesystems which support encryption, this commit removes
filesystem specific build config option (e.g. CONFIG_EXT4_FS_ENCRYPTION)
and replaces it with a build option (i.e. CONFIG_FS_ENCRYPTION) whose
value affects all the filesystems making use of fscrypt.
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
This link is replicated in most filesystems' config stanzas. Referring
to an archived version of that site is pointless as it mostly deals with
patches; user documentation is available elsewhere.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
CC: Alexander Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: "Yan, Zheng" <zyan@redhat.com>
Acked-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Acked-by: Steve French <smfrench@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The crc function is done bit by bit.
Optimize this by use cryptoapi
crc32 function which is backed by h/w acceleration.
Signed-off-by: Keith Mok <ek9852@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds the renamed functions moved from the f2fs crypto files.
1. definitions for per-file encryption used by ext4 and f2fs.
2. crypto.c for encrypt/decrypt functions
a. IO preparation:
- fscrypt_get_ctx / fscrypt_release_ctx
b. before IOs:
- fscrypt_encrypt_page
- fscrypt_decrypt_page
- fscrypt_zeroout_range
c. after IOs:
- fscrypt_decrypt_bio_pages
- fscrypt_pullback_bio_page
- fscrypt_restore_control_page
3. policy.c supporting context management.
a. For ioctls:
- fscrypt_process_policy
- fscrypt_get_policy
b. For context permission
- fscrypt_has_permitted_context
- fscrypt_inherit_context
4. keyinfo.c to handle permissions
- fscrypt_get_encryption_info
- fscrypt_free_encryption_info
5. fname.c to support filename encryption
a. general wrapper functions
- fscrypt_fname_disk_to_usr
- fscrypt_fname_usr_to_disk
- fscrypt_setup_filename
- fscrypt_free_filename
b. specific filename handling functions
- fscrypt_fname_alloc_buffer
- fscrypt_fname_free_buffer
6. Makefile and Kconfig
Cc: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Uday Savagaonkar <savagaon@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds f2fs encryption config.
This patch integrates:
"ext4 crypto: require CONFIG_CRYPTO_CTR if ext4 encryption is enabled
On arm64 this is apparently needed for CTS mode to function correctly.
Otherwise attempts to use CTS return ENOENT."
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The f2fs has been shipped on many smartphone devices during a couple of years.
So, it is worth to relocate Kconfig into main page from misc filesystems for
developers to choose it more easily.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds:
o initial trace.c and trace.h with skeleton functions
o Kconfig and Makefile to activate this feature
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Fix typo and some grammatical errors.
The words "filesystem" and "readahead" are being used without the space treewide.
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This config will support an option to remove so many BUG_ONs that degrade
the performance potentially.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch adds the support of security labels for f2fs, which will be used
by Linus Security Models (LSMs).
Quote from http://en.wikipedia.org/wiki/Linux_Security_Modules:
"Linux Security Modules (LSM) is a framework that allows the Linux kernel to
support a variety of computer security models while avoiding favoritism toward
any single security implementation. The framework is licensed under the terms of
the GNU General Public License and is standard part of the Linux kernel since
Linux 2.6. AppArmor, SELinux, Smack and TOMOYO Linux are the currently accepted
modules in the official kernel.".
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
There exist two build failures reported by Randy Dunlap as follows.
(on i386)
a. (config-r8857)
ERROR: "f2fs_xattr_advise_handler" [fs/f2fs/f2fs.ko] undefined!
Key configs in (config-r8857) are as follows.
CONFIG_F2FS_FS=m
# CONFIG_F2FS_STAT_FS is not set
CONFIG_F2FS_FS_XATTR=y
# CONFIG_F2FS_FS_POSIX_ACL is not set
The error was occurred due to the function location that we made a mistake.
Recently we added a new functionality for users to indicate cold files
explicitly through xattr operations (i.e., f2fs_xattr_advise_handler).
This handler should have been added in xattr.c instead of acl.c in order
to avoid an undefined operation like in this case where XATTR is set and
ACL is not set.
b. (config-r8855)
fs/f2fs/file.c: In function 'f2fs_vm_page_mkwrite':
fs/f2fs/file.c:97:2: error: implicit declaration of function
'block_page_mkwrite_return'
Key config in (config-r8855) is CONFIG_BLOCK.
Obviously, f2fs works on top of the block device so that we should consider
carefully a sort of config dependencies.
The reason why this error was occurred was that f2fs_vm_page_mkwrite() calls
block_page_mkwrite_return() which is enalbed only if CONFIG_BLOCK is set.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
This adds Makefile and Kconfig for f2fs, and updates Makefile and Kconfig files
in the fs directory.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
