Once F2FS_IPU_FORCE policy is enabled in some cases:
a) f2fs forces to use F2FS_IPU_FORCE in a small-sized volume
b) user sets F2FS_IPU_FORCE policy via sysfs
Then we may fail to defragment file due to IPU policy check, it doesn't
make sense, let's introduce a new IPU policy to allow OPU during file
defragmentation.
In small-sized volume, let's enable F2FS_IPU_HONOR_OPU_WRITE policy
by default.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs rw_semaphores work better if writers can starve readers,
especially for the checkpoint thread, because writers are strictly
more important than reader threads. This prevents significant priority
inversion between low-priority readers that blocked while trying to
acquire the read lock and a second acquisition of the write lock that
might be blocking high priority work.
Signed-off-by: Tim Murray <timmurray@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this round, we've tried to address some performance issues in f2fs_checkpoint
and direct IO flows. Also, there was a work to enhance the page cache management
used for compression. Other than them, we've done typical work including sysfs,
code clean-ups, tracepoint, sanity check, in addition to bug fixes on corner
cases.
Enhancement:
- use iomap for direct IO
- try to avoid lock contention to improve f2fs_ckpt speed
- avoid unnecessary memory allocation in compression flow
- POSIX_FADV_DONTNEED drops the page cache containing compression pages
- add some sysfs entries (gc_urgent_high_remaining, pending_discard)
Bug fix:
- try not to expose unwritten blocks to user by DIO
: this was added to avoid merge conflict; another patch is coming to address
other missing case.
- relax minor error condition for file pinning feature used in Android OTA
- fix potential deadlock case in compression flow
- should not truncate any block on pinned file
In addition, we've done some code clean-ups and tracepoint/sanity check
improvement.
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Merge tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've tried to address some performance issues in
f2fs_checkpoint and direct IO flows. Also, there was a work to enhance
the page cache management used for compression. Other than them, we've
done typical work including sysfs, code clean-ups, tracepoint, sanity
check, in addition to bug fixes on corner cases.
Enhancements:
- use iomap for direct IO
- try to avoid lock contention to improve f2fs_ckpt speed
- avoid unnecessary memory allocation in compression flow
- POSIX_FADV_DONTNEED drops the page cache containing compression
pages
- add some sysfs entries (gc_urgent_high_remaining, pending_discard)
Bug fixes:
- try not to expose unwritten blocks to user by DIO (this was added
to avoid merge conflict; another patch is coming to address other
missing case)
- relax minor error condition for file pinning feature used in
Android OTA
- fix potential deadlock case in compression flow
- should not truncate any block on pinned file
In addition, we've done some code clean-ups and tracepoint/sanity
check improvement"
* tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits)
f2fs: do not allow partial truncation on pinned file
f2fs: remove redunant invalidate compress pages
f2fs: Simplify bool conversion
f2fs: don't drop compressed page cache in .{invalidate,release}page
f2fs: fix to reserve space for IO align feature
f2fs: fix to check available space of CP area correctly in update_ckpt_flags()
f2fs: support fault injection to f2fs_trylock_op()
f2fs: clean up __find_inline_xattr() with __find_xattr()
f2fs: fix to do sanity check on last xattr entry in __f2fs_setxattr()
f2fs: do not bother checkpoint by f2fs_get_node_info
f2fs: avoid down_write on nat_tree_lock during checkpoint
f2fs: compress: fix potential deadlock of compress file
f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file
f2fs: add gc_urgent_high_remaining sysfs node
f2fs: fix to do sanity check in is_alive()
f2fs: fix to avoid panic in is_alive() if metadata is inconsistent
f2fs: fix to do sanity check on inode type during garbage collection
f2fs: avoid duplicate call of mark_inode_dirty
f2fs: show number of pending discard commands
f2fs: support POSIX_FADV_DONTNEED drop compressed page cache
...
This includes patches from Christoph Hellwig to split the large data
tables of the unicode subsystem into a loadable module, which allow
users to not have them around if case-insensitive filesystems are not to
be used. It also includes minor code fixes to unicode and its users,
from the same author.
There is a trivial conflict in the function encoding_show in
fs/f2fs/sysfs.c reported by linux-next between commit
84eab2a899 ("f2fs: replace snprintf in show functions with sysfs_emit")
and commit a440943e68 ("unicode: remove the charset field from struct
unicode_map"). from my tree.
All the patches here have been on linux-next releases for the past
months.
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
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Merge tag 'unicode-for-next-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode
Pull unicode updates from Gabriel Krisman Bertazi:
"This includes patches from Christoph Hellwig to split the large data
tables of the unicode subsystem into a loadable module, which allow
users to not have them around if case-insensitive filesystems are not
to be used. It also includes minor code fixes to unicode and its
users, from the same author.
All the patches here have been on linux-next releases for the past
months"
* tag 'unicode-for-next-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode:
unicode: only export internal symbols for the selftests
unicode: Add utf8-data module
unicode: cache the normalization tables in struct unicode_map
unicode: move utf8cursor to utf8-selftest.c
unicode: simplify utf8len
unicode: remove the unused utf8{,n}age{min,max} functions
unicode: pass a UNICODE_AGE() tripple to utf8_load
unicode: mark the version field in struct unicode_map unsigned
unicode: remove the charset field from struct unicode_map
f2fs: simplify f2fs_sb_read_encoding
ext4: simplify ext4_sb_read_encoding
Various places in the kernel - largely in filesystems - respond to a
memory allocation failure by looping around and re-trying. Some of
these cannot conveniently use __GFP_NOFAIL, for reasons such as:
- a GFP_ATOMIC allocation, which __GFP_NOFAIL doesn't work on
- a need to check for the process being signalled between failures
- the possibility that other recovery actions could be performed
- the allocation is quite deep in support code, and passing down an
extra flag to say if __GFP_NOFAIL is wanted would be clumsy.
Many of these currently use congestion_wait() which (in almost all
cases) simply waits the given timeout - congestion isn't tracked for
most devices.
It isn't clear what the best delay is for loops, but it is clear that
the various filesystems shouldn't be responsible for choosing a timeout.
This patch introduces memalloc_retry_wait() with takes on that
responsibility. Code that wants to retry a memory allocation can call
this function passing the GFP flags that were used. It will wait
however is appropriate.
For now, it only considers __GFP_NORETRY and whatever
gfpflags_allow_blocking() tests. If blocking is allowed without
__GFP_NORETRY, then alloc_page either made some reclaim progress, or
waited for a while, before failing. So there is no need for much
further waiting. memalloc_retry_wait() will wait until the current
jiffie ends. If this condition is not met, then alloc_page() won't have
waited much if at all. In that case memalloc_retry_wait() waits about
200ms. This is the delay that most current loops uses.
linux/sched/mm.h needs to be included in some files now,
but linux/backing-dev.h does not.
Link: https://lkml.kernel.org/r/163754371968.13692.1277530886009912421@noble.neil.brown.name
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
https://bugzilla.kernel.org/show_bug.cgi?id=204137
With below script, we will hit panic during new segment allocation:
DISK=bingo.img
MOUNT_DIR=/mnt/f2fs
dd if=/dev/zero of=$DISK bs=1M count=105
mkfs.f2fe -a 1 -o 19 -t 1 -z 1 -f -q $DISK
mount -t f2fs $DISK $MOUNT_DIR -o "noinline_dentry,flush_merge,noextent_cache,mode=lfs,io_bits=7,fsync_mode=strict"
for (( i = 0; i < 4096; i++ )); do
name=`head /dev/urandom | tr -dc A-Za-z0-9 | head -c 10`
mkdir $MOUNT_DIR/$name
done
umount $MOUNT_DIR
rm $DISK
--- Core dump ---
Call Trace:
allocate_segment_by_default+0x9d/0x100 [f2fs]
f2fs_allocate_data_block+0x3c0/0x5c0 [f2fs]
do_write_page+0x62/0x110 [f2fs]
f2fs_outplace_write_data+0x43/0xc0 [f2fs]
f2fs_do_write_data_page+0x386/0x560 [f2fs]
__write_data_page+0x706/0x850 [f2fs]
f2fs_write_cache_pages+0x267/0x6a0 [f2fs]
f2fs_write_data_pages+0x19c/0x2e0 [f2fs]
do_writepages+0x1c/0x70
__filemap_fdatawrite_range+0xaa/0xe0
filemap_fdatawrite+0x1f/0x30
f2fs_sync_dirty_inodes+0x74/0x1f0 [f2fs]
block_operations+0xdc/0x350 [f2fs]
f2fs_write_checkpoint+0x104/0x1150 [f2fs]
f2fs_sync_fs+0xa2/0x120 [f2fs]
f2fs_balance_fs_bg+0x33c/0x390 [f2fs]
f2fs_write_node_pages+0x4c/0x1f0 [f2fs]
do_writepages+0x1c/0x70
__writeback_single_inode+0x45/0x320
writeback_sb_inodes+0x273/0x5c0
wb_writeback+0xff/0x2e0
wb_workfn+0xa1/0x370
process_one_work+0x138/0x350
worker_thread+0x4d/0x3d0
kthread+0x109/0x140
ret_from_fork+0x25/0x30
The root cause here is, with IO alignment feature enables, in worst
case, we need F2FS_IO_SIZE() free blocks space for single one 4k write
due to IO alignment feature will fill dummy pages to make IO being
aligned.
So we will easily run out of free segments during non-inline directory's
data writeback, even in process of foreground GC.
In order to fix this issue, I just propose to reserve additional free
space for IO alignment feature to handle worst case of free space usage
ratio during FGGC.
Fixes: 0a595ebaaa ("f2fs: support IO alignment for DATA and NODE writes")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs: support fault injection for f2fs_trylock_op()
This patch supports to inject fault into f2fs_trylock_op().
Usage:
a) echo 65536 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=65536 <dev> <mountpoint>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Added a new sysfs node called gc_urgent_high_remaining. The user can
set the trial count limit for GC urgent high mode with this value. If
GC thread gets to the limit, the mode will turn back to GC normal mode.
By default, the value is zero, which means there is no limit like before.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This PR includes 5 commits that update the zstd library version:
1. Adds a new kernel-style wrapper around zstd. This wrapper API
is functionally equivalent to the subset of the current zstd API that is
currently used. The wrapper API changes to be kernel style so that the symbols
don't collide with zstd's symbols. The update to zstd-1.4.10 maintains the same
API and preserves the semantics, so that none of the callers need to be
updated. All callers are updated in the commit, because there are zero
functional changes.
2. Adds an indirection for `lib/decompress_unzstd.c` so it
doesn't depend on the layout of `lib/zstd/` to include every source file.
This allows the next patch to be automatically generated.
3. Imports the zstd-1.4.10 source code. This commit is automatically generated
from upstream zstd (https://github.com/facebook/zstd).
4. Adds me (terrelln@fb.com) as the maintainer of `lib/zstd`.
5. Fixes a newly added build warning for clang.
The discussion around this patchset has been pretty long, so I've included a
FAQ-style summary of the history of the patchset, and why we are taking this
approach.
Why do we need to update?
-------------------------
The zstd version in the kernel is based off of zstd-1.3.1, which is was released
August 20, 2017. Since then zstd has seen many bug fixes and performance
improvements. And, importantly, upstream zstd is continuously fuzzed by OSS-Fuzz,
and bug fixes aren't backported to older versions. So the only way to sanely get
these fixes is to keep up to date with upstream zstd. There are no known security
issues that affect the kernel, but we need to be able to update in case there
are. And while there are no known security issues, there are relevant bug fixes.
For example the problem with large kernel decompression has been fixed upstream
for over 2 years https://lkml.org/lkml/2020/9/29/27.
Additionally the performance improvements for kernel use cases are significant.
Measured for x86_64 on my Intel i9-9900k @ 3.6 GHz:
- BtrFS zstd compression at levels 1 and 3 is 5% faster
- BtrFS zstd decompression+read is 15% faster
- SquashFS zstd decompression+read is 15% faster
- F2FS zstd compression+write at level 3 is 8% faster
- F2FS zstd decompression+read is 20% faster
- ZRAM decompression+read is 30% faster
- Kernel zstd decompression is 35% faster
- Initramfs zstd decompression+build is 5% faster
On top of this, there are significant performance improvements coming down the
line in the next zstd release, and the new automated update patch generation
will allow us to pull them easily.
How is the update patch generated?
----------------------------------
The first two patches are preparation for updating the zstd version. Then the
3rd patch in the series imports upstream zstd into the kernel. This patch is
automatically generated from upstream. A script makes the necessary changes and
imports it into the kernel. The changes are:
- Replace all libc dependencies with kernel replacements and rewrite includes.
- Remove unncessary portability macros like: #if defined(_MSC_VER).
- Use the kernel xxhash instead of bundling it.
This automation gets tested every commit by upstream's continuous integration.
When we cut a new zstd release, we will submit a patch to the kernel to update
the zstd version in the kernel.
The automated process makes it easy to keep the kernel version of zstd up to
date. The current zstd in the kernel shares the guts of the code, but has a lot
of API and minor changes to work in the kernel. This is because at the time
upstream zstd was not ready to be used in the kernel envrionment as-is. But,
since then upstream zstd has evolved to support being used in the kernel as-is.
Why are we updating in one big patch?
-------------------------------------
The 3rd patch in the series is very large. This is because it is restructuring
the code, so it both deletes the existing zstd, and re-adds the new structure.
Future updates will be directly proportional to the changes in upstream zstd
since the last import. They will admittidly be large, as zstd is an actively
developed project, and has hundreds of commits between every release. However,
there is no other great alternative.
One option ruled out is to replay every upstream zstd commit. This is not feasible
for several reasons:
- There are over 3500 upstream commits since the zstd version in the kernel.
- The automation to automatically generate the kernel update was only added recently,
so older commits cannot easily be imported.
- Not every upstream zstd commit builds.
- Only zstd releases are "supported", and individual commits may have bugs that were
fixed before a release.
Another option to reduce the patch size would be to first reorganize to the new
file structure, and then apply the patch. However, the current kernel zstd is formatted
with clang-format to be more "kernel-like". But, the new method imports zstd as-is,
without additional formatting, to allow for closer correlation with upstream, and
easier debugging. So the patch wouldn't be any smaller.
It also doesn't make sense to import upstream zstd commit by commit going
forward. Upstream zstd doesn't support production use cases running of the
development branch. We have a lot of post-commit fuzzing that catches many bugs,
so indiviudal commits may be buggy, but fixed before a release. So going forward,
I intend to import every (important) zstd release into the Kernel.
So, while it isn't ideal, updating in one big patch is the only patch I see forward.
Who is responsible for this code?
---------------------------------
I am. This patchset adds me as the maintainer for zstd. Previously, there was no tree
for zstd patches. Because of that, there were several patches that either got ignored,
or took a long time to merge, since it wasn't clear which tree should pick them up.
I'm officially stepping up as maintainer, and setting up my tree as the path through
which zstd patches get merged. I'll make sure that patches to the kernel zstd get
ported upstream, so they aren't erased when the next version update happens.
How is this code tested?
------------------------
I tested every caller of zstd on x86_64 (BtrFS, ZRAM, SquashFS, F2FS, Kernel,
InitRAMFS). I also tested Kernel & InitRAMFS on i386 and aarch64. I checked both
performance and correctness.
Also, thanks to many people in the community who have tested these patches locally.
If you have tested the patches, please reply with a Tested-By so I can collect them
for the PR I will send to Linus.
Lastly, this code will bake in linux-next before being merged into v5.16.
Why update to zstd-1.4.10 when zstd-1.5.0 has been released?
------------------------------------------------------------
This patchset has been outstanding since 2020, and zstd-1.4.10 was the latest
release when it was created. Since the update patch is automatically generated
from upstream, I could generate it from zstd-1.5.0. However, there were some
large stack usage regressions in zstd-1.5.0, and are only fixed in the latest
development branch. And the latest development branch contains some new code that
needs to bake in the fuzzer before I would feel comfortable releasing to the
kernel.
Once this patchset has been merged, and we've released zstd-1.5.1, we can update
the kernel to zstd-1.5.1, and exercise the update process.
You may notice that zstd-1.4.10 doesn't exist upstream. This release is an
artifical release based off of zstd-1.4.9, with some fixes for the kernel
backported from the development branch. I will tag the zstd-1.4.10 release after
this patchset is merged, so the Linux Kernel is running a known version of zstd
that can be debugged upstream.
Why was a wrapper API added?
----------------------------
The first versions of this patchset migrated the kernel to the upstream zstd
API. It first added a shim API that supported the new upstream API with the old
code, then updated callers to use the new shim API, then transitioned to the
new code and deleted the shim API. However, Cristoph Hellwig suggested that we
transition to a kernel style API, and hide zstd's upstream API behind that.
This is because zstd's upstream API is supports many other use cases, and does
not follow the kernel style guide, while the kernel API is focused on the
kernel's use cases, and follows the kernel style guide.
Where is the previous discussion?
---------------------------------
Links for the discussions of the previous versions of the patch set.
The largest changes in the design of the patchset are driven by the discussions
in V11, V5, and V1. Sorry for the mix of links, I couldn't find most of the the
threads on lkml.org.
V12: https://www.spinics.net/lists/linux-crypto/msg58189.html
V11: https://lore.kernel.org/linux-btrfs/20210430013157.747152-1-nickrterrell@gmail.com/
V10: https://lore.kernel.org/lkml/20210426234621.870684-2-nickrterrell@gmail.com/
V9: https://lore.kernel.org/linux-btrfs/20210330225112.496213-1-nickrterrell@gmail.com/
V8: https://lore.kernel.org/linux-f2fs-devel/20210326191859.1542272-1-nickrterrell@gmail.com/
V7: https://lkml.org/lkml/2020/12/3/1195
V6: https://lkml.org/lkml/2020/12/2/1245
V5: https://lore.kernel.org/linux-btrfs/20200916034307.2092020-1-nickrterrell@gmail.com/
V4: https://www.spinics.net/lists/linux-btrfs/msg105783.html
V3: https://lkml.org/lkml/2020/9/23/1074
V2: https://www.spinics.net/lists/linux-btrfs/msg105505.html
V1: https://lore.kernel.org/linux-btrfs/20200916034307.2092020-1-nickrterrell@gmail.com/
Signed-off-by: Nick Terrell <terrelln@fb.com>
Tested By: Paul Jones <paul@pauljones.id.au>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 on x86-64
Tested-by: Jean-Denis Girard <jd.girard@sysnux.pf>
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Merge tag 'zstd-for-linus-v5.16' of git://github.com/terrelln/linux
Pull zstd update from Nick Terrell:
"Update to zstd-1.4.10.
Add myself as the maintainer of zstd and update the zstd version in
the kernel, which is now 4 years out of date, to a much more recent
zstd release. This includes bug fixes, much more extensive fuzzing,
and performance improvements. And generates the kernel zstd
automatically from upstream zstd, so it is easier to keep the zstd
verison up to date, and we don't fall so far out of date again.
This includes 5 commits that update the zstd library version:
- Adds a new kernel-style wrapper around zstd.
This wrapper API is functionally equivalent to the subset of the
current zstd API that is currently used. The wrapper API changes to
be kernel style so that the symbols don't collide with zstd's
symbols. The update to zstd-1.4.10 maintains the same API and
preserves the semantics, so that none of the callers need to be
updated. All callers are updated in the commit, because there are
zero functional changes.
- Adds an indirection for `lib/decompress_unzstd.c` so it doesn't
depend on the layout of `lib/zstd/` to include every source file.
This allows the next patch to be automatically generated.
- Imports the zstd-1.4.10 source code. This commit is automatically
generated from upstream zstd (https://github.com/facebook/zstd).
- Adds me (terrelln@fb.com) as the maintainer of `lib/zstd`.
- Fixes a newly added build warning for clang.
The discussion around this patchset has been pretty long, so I've
included a FAQ-style summary of the history of the patchset, and why
we are taking this approach.
Why do we need to update?
-------------------------
The zstd version in the kernel is based off of zstd-1.3.1, which is
was released August 20, 2017. Since then zstd has seen many bug fixes
and performance improvements. And, importantly, upstream zstd is
continuously fuzzed by OSS-Fuzz, and bug fixes aren't backported to
older versions. So the only way to sanely get these fixes is to keep
up to date with upstream zstd.
There are no known security issues that affect the kernel, but we need
to be able to update in case there are. And while there are no known
security issues, there are relevant bug fixes. For example the problem
with large kernel decompression has been fixed upstream for over 2
years [1]
Additionally the performance improvements for kernel use cases are
significant. Measured for x86_64 on my Intel i9-9900k @ 3.6 GHz:
- BtrFS zstd compression at levels 1 and 3 is 5% faster
- BtrFS zstd decompression+read is 15% faster
- SquashFS zstd decompression+read is 15% faster
- F2FS zstd compression+write at level 3 is 8% faster
- F2FS zstd decompression+read is 20% faster
- ZRAM decompression+read is 30% faster
- Kernel zstd decompression is 35% faster
- Initramfs zstd decompression+build is 5% faster
On top of this, there are significant performance improvements coming
down the line in the next zstd release, and the new automated update
patch generation will allow us to pull them easily.
How is the update patch generated?
----------------------------------
The first two patches are preparation for updating the zstd version.
Then the 3rd patch in the series imports upstream zstd into the
kernel. This patch is automatically generated from upstream. A script
makes the necessary changes and imports it into the kernel. The
changes are:
- Replace all libc dependencies with kernel replacements and rewrite
includes.
- Remove unncessary portability macros like: #if defined(_MSC_VER).
- Use the kernel xxhash instead of bundling it.
This automation gets tested every commit by upstream's continuous
integration. When we cut a new zstd release, we will submit a patch to
the kernel to update the zstd version in the kernel.
The automated process makes it easy to keep the kernel version of zstd
up to date. The current zstd in the kernel shares the guts of the
code, but has a lot of API and minor changes to work in the kernel.
This is because at the time upstream zstd was not ready to be used in
the kernel envrionment as-is. But, since then upstream zstd has
evolved to support being used in the kernel as-is.
Why are we updating in one big patch?
-------------------------------------
The 3rd patch in the series is very large. This is because it is
restructuring the code, so it both deletes the existing zstd, and
re-adds the new structure. Future updates will be directly
proportional to the changes in upstream zstd since the last import.
They will admittidly be large, as zstd is an actively developed
project, and has hundreds of commits between every release. However,
there is no other great alternative.
One option ruled out is to replay every upstream zstd commit. This is
not feasible for several reasons:
- There are over 3500 upstream commits since the zstd version in the
kernel.
- The automation to automatically generate the kernel update was only
added recently, so older commits cannot easily be imported.
- Not every upstream zstd commit builds.
- Only zstd releases are "supported", and individual commits may have
bugs that were fixed before a release.
Another option to reduce the patch size would be to first reorganize
to the new file structure, and then apply the patch. However, the
current kernel zstd is formatted with clang-format to be more
"kernel-like". But, the new method imports zstd as-is, without
additional formatting, to allow for closer correlation with upstream,
and easier debugging. So the patch wouldn't be any smaller.
It also doesn't make sense to import upstream zstd commit by commit
going forward. Upstream zstd doesn't support production use cases
running of the development branch. We have a lot of post-commit
fuzzing that catches many bugs, so indiviudal commits may be buggy,
but fixed before a release. So going forward, I intend to import every
(important) zstd release into the Kernel.
So, while it isn't ideal, updating in one big patch is the only patch
I see forward.
Who is responsible for this code?
---------------------------------
I am. This patchset adds me as the maintainer for zstd. Previously,
there was no tree for zstd patches. Because of that, there were
several patches that either got ignored, or took a long time to merge,
since it wasn't clear which tree should pick them up. I'm officially
stepping up as maintainer, and setting up my tree as the path through
which zstd patches get merged. I'll make sure that patches to the
kernel zstd get ported upstream, so they aren't erased when the next
version update happens.
How is this code tested?
------------------------
I tested every caller of zstd on x86_64 (BtrFS, ZRAM, SquashFS, F2FS,
Kernel, InitRAMFS). I also tested Kernel & InitRAMFS on i386 and
aarch64. I checked both performance and correctness.
Also, thanks to many people in the community who have tested these
patches locally.
Lastly, this code will bake in linux-next before being merged into
v5.16.
Why update to zstd-1.4.10 when zstd-1.5.0 has been released?
------------------------------------------------------------
This patchset has been outstanding since 2020, and zstd-1.4.10 was the
latest release when it was created. Since the update patch is
automatically generated from upstream, I could generate it from
zstd-1.5.0.
However, there were some large stack usage regressions in zstd-1.5.0,
and are only fixed in the latest development branch. And the latest
development branch contains some new code that needs to bake in the
fuzzer before I would feel comfortable releasing to the kernel.
Once this patchset has been merged, and we've released zstd-1.5.1, we
can update the kernel to zstd-1.5.1, and exercise the update process.
You may notice that zstd-1.4.10 doesn't exist upstream. This release
is an artifical release based off of zstd-1.4.9, with some fixes for
the kernel backported from the development branch. I will tag the
zstd-1.4.10 release after this patchset is merged, so the Linux Kernel
is running a known version of zstd that can be debugged upstream.
Why was a wrapper API added?
----------------------------
The first versions of this patchset migrated the kernel to the
upstream zstd API. It first added a shim API that supported the new
upstream API with the old code, then updated callers to use the new
shim API, then transitioned to the new code and deleted the shim API.
However, Cristoph Hellwig suggested that we transition to a kernel
style API, and hide zstd's upstream API behind that. This is because
zstd's upstream API is supports many other use cases, and does not
follow the kernel style guide, while the kernel API is focused on the
kernel's use cases, and follows the kernel style guide.
Where is the previous discussion?
---------------------------------
Links for the discussions of the previous versions of the patch set
below. The largest changes in the design of the patchset are driven by
the discussions in v11, v5, and v1. Sorry for the mix of links, I
couldn't find most of the the threads on lkml.org"
Link: https://lkml.org/lkml/2020/9/29/27 [1]
Link: https://www.spinics.net/lists/linux-crypto/msg58189.html [v12]
Link: https://lore.kernel.org/linux-btrfs/20210430013157.747152-1-nickrterrell@gmail.com/ [v11]
Link: https://lore.kernel.org/lkml/20210426234621.870684-2-nickrterrell@gmail.com/ [v10]
Link: https://lore.kernel.org/linux-btrfs/20210330225112.496213-1-nickrterrell@gmail.com/ [v9]
Link: https://lore.kernel.org/linux-f2fs-devel/20210326191859.1542272-1-nickrterrell@gmail.com/ [v8]
Link: https://lkml.org/lkml/2020/12/3/1195 [v7]
Link: https://lkml.org/lkml/2020/12/2/1245 [v6]
Link: https://lore.kernel.org/linux-btrfs/20200916034307.2092020-1-nickrterrell@gmail.com/ [v5]
Link: https://www.spinics.net/lists/linux-btrfs/msg105783.html [v4]
Link: https://lkml.org/lkml/2020/9/23/1074 [v3]
Link: https://www.spinics.net/lists/linux-btrfs/msg105505.html [v2]
Link: https://lore.kernel.org/linux-btrfs/20200916034307.2092020-1-nickrterrell@gmail.com/ [v1]
Signed-off-by: Nick Terrell <terrelln@fb.com>
Tested By: Paul Jones <paul@pauljones.id.au>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 on x86-64
Tested-by: Jean-Denis Girard <jd.girard@sysnux.pf>
* tag 'zstd-for-linus-v5.16' of git://github.com/terrelln/linux:
lib: zstd: Add cast to silence clang's -Wbitwise-instead-of-logical
MAINTAINERS: Add maintainer entry for zstd
lib: zstd: Upgrade to latest upstream zstd version 1.4.10
lib: zstd: Add decompress_sources.h for decompress_unzstd
lib: zstd: Add kernel-specific API
In this cycle, we've applied relatively small number of patches which fix subtle
corner cases mainly, while introducing a new mount option to be able to fragment
the disk intentionally for performance tests.
Enhancement:
- add a mount option to fragmente on-disk layout to understand the performance
- support direct IO for multi-partitions
- add a fault injection of dquot_initialize
Bug fix:
- address some lockdep complaints
- fix a deadlock issue with quota
- fix a memory tuning condition
- fix compression condition to improve the ratio
- fix disabling compression on the non-empty compressed file
- invalidate cached pages before IPU/DIO writes
And, we've added some minor clean-ups as usual.
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Merge tag 'f2fs-for-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this cycle, we've applied relatively small number of patches which
fix subtle corner cases mainly, while introducing a new mount option
to be able to fragment the disk intentionally for performance tests.
Enhancements:
- add a mount option to fragmente on-disk layout to understand the
performance
- support direct IO for multi-partitions
- add a fault injection of dquot_initialize
Bug fixes:
- address some lockdep complaints
- fix a deadlock issue with quota
- fix a memory tuning condition
- fix compression condition to improve the ratio
- fix disabling compression on the non-empty compressed file
- invalidate cached pages before IPU/DIO writes
And, we've added some minor clean-ups as usual"
* tag 'f2fs-for-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
f2fs: fix UAF in f2fs_available_free_memory
f2fs: invalidate META_MAPPING before IPU/DIO write
f2fs: support fault injection for dquot_initialize()
f2fs: fix incorrect return value in f2fs_sanity_check_ckpt()
f2fs: compress: disallow disabling compress on non-empty compressed file
f2fs: compress: fix overwrite may reduce compress ratio unproperly
f2fs: multidevice: support direct IO
f2fs: introduce fragment allocation mode mount option
f2fs: replace snprintf in show functions with sysfs_emit
f2fs: include non-compressed blocks in compr_written_block
f2fs: fix wrong condition to trigger background checkpoint correctly
f2fs: fix to use WHINT_MODE
f2fs: fix up f2fs_lookup tracepoints
f2fs: set SBI_NEED_FSCK flag when inconsistent node block found
f2fs: introduce excess_dirty_threshold()
f2fs: avoid attaching SB_ACTIVE flag during mount
f2fs: quota: fix potential deadlock
f2fs: should use GFP_NOFS for directory inodes
if2fs_fill_super
-> f2fs_build_segment_manager
-> create_discard_cmd_control
-> f2fs_start_discard_thread
It invokes kthread_run to create a thread and run issue_discard_thread.
However, if f2fs_build_node_manager fails, the control flow goes to
free_nm and calls f2fs_destroy_node_manager. This function will free
sbi->nm_info. However, if issue_discard_thread accesses sbi->nm_info
after the deallocation, but before the f2fs_stop_discard_thread, it will
cause UAF(Use-after-free).
-> f2fs_destroy_segment_manager
-> destroy_discard_cmd_control
-> f2fs_stop_discard_thread
Fix this by stopping discard thread before f2fs_destroy_node_manager.
Note that, the commit d6d2b491a8 introduces the call of
f2fs_available_free_memory into issue_discard_thread.
Cc: stable@vger.kernel.org
Fixes: d6d2b491a8 ("f2fs: allow to change discard policy based on cached discard cmds")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch:
- Moves `include/linux/zstd.h` -> `include/linux/zstd_lib.h`
- Updates modified zstd headers to yearless copyright
- Adds a new API in `include/linux/zstd.h` that is functionally
equivalent to the in-use subset of the current API. Functions are
renamed to avoid symbol collisions with zstd, to make it clear it is
not the upstream zstd API, and to follow the kernel style guide.
- Updates all callers to use the new API.
There are no functional changes in this patch. Since there are no
functional change, I felt it was okay to update all the callers in a
single patch. Once the API is approved, the callers are mechanically
changed.
This patch is preparing for the 3rd patch in this series, which updates
zstd to version 1.4.10. Since the upstream zstd API is no longer exposed
to callers, the update can happen transparently.
Signed-off-by: Nick Terrell <terrelln@fb.com>
Tested By: Paul Jones <paul@pauljones.id.au>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 on x86-64
Tested-by: Jean-Denis Girard <jd.girard@sysnux.pf>
This patch adds a new function f2fs_dquot_initialize() to wrap
dquot_initialize(), and it supports to inject fault into
f2fs_dquot_initialize() to simulate inner failure occurs in
dquot_initialize().
Usage:
a) echo 65536 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=65536 <dev> <mountpoint>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As Pavel Machek reported in [1]
This code looks quite confused: part of function returns 1 on
corruption, part returns -errno. The problem is not stable-specific.
[1] https://lkml.org/lkml/2021/9/19/207
Let's fix to make 'insane cp_payload case' to return 1 rater than
EFSCORRUPTED, so that return value can be kept consistent for all
error cases, it can avoid confusion of code logic.
Fixes: 65ddf65648 ("f2fs: fix to do sanity check for sb/cp fields correctly")
Reported-by: Pavel Machek <pavel@denx.de>
Reviewed-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Commit 3c62be17d4 ("f2fs: support multiple devices") missed
to support direct IO for multiple device feature, this patch
adds to support the missing part of multidevice feature.
In addition, for multiple device image, we should be aware of
any issued direct write IO rather than just buffered write IO,
so that fsync and syncfs can issue a preflush command to the
device where direct write IO goes, to persist user data for
posix compliant.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Added two options into "mode=" mount option to make it possible for
developers to simulate filesystem fragmentation/after-GC situation
itself. The developers use these modes to understand filesystem
fragmentation/after-GC condition well, and eventually get some
insights to handle them better.
"fragment:segment": f2fs allocates a new segment in ramdom position.
With this, we can simulate the after-GC condition.
"fragment:block" : We can scatter block allocation with
"max_fragment_chunk" and "max_fragment_hole" sysfs
nodes. f2fs will allocate 1..<max_fragment_chunk>
blocks in a chunk and make a hole in the length of
1..<max_fragment_hole> by turns in a newly allocated
free segment. Plus, this mode implicitly enables
"fragment:segment" option for more randomness.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Since active_logs can be set to 2 or 4 or NR_CURSEG_PERSIST_TYPE(6),
it cannot be set to NR_CURSEG_TYPE(8).
That is, whint_mode is always off.
Therefore, the condition is changed from NR_CURSEG_TYPE to NR_CURSEG_PERSIST_TYPE.
Cc: Chao Yu <chao@kernel.org>
Fixes: d0b9e42ab6 (f2fs: introduce inmem curseg)
Reported-by: tanghuan <tanghuan@vivo.com>
Signed-off-by: Keoseong Park <keosung.park@samsung.com>
Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Don't bother with pointless string parsing when the caller can just pass
the version in the format that the core expects. Also remove the
fallback to the latest version that none of the callers actually uses.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Return the encoding table as the return value instead of as an argument,
and don't bother with the encoding flags as the caller can handle that
trivially.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
The max_namelen field is unnecessary, as it is set to 255 (NAME_MAX) on
all filesystems that support fscrypt (or plan to support fscrypt). For
simplicity, just use NAME_MAX directly instead.
Link: https://lore.kernel.org/r/20210909184513.139281-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
In this cycle, we've addressed some performance issues such as lock contention,
misbehaving compress_cache, allowing extent_cache for compressed files, and new
sysfs to adjust ra_size for fadvise. In order to diagnose the performance issues
quickly, we also added an iostat which shows the IO latencies periodically. On
the stability side, we've found two memory leakage cases in the error path in
compression flow. And, we've also fixed various corner cases in fiemap, quota,
checkpoint=disable, zstd, and so on.
Enhancement:
- avoid long checkpoint latency by releasing nat_tree_lock
- collect and show iostats periodically
- support extent_cache for compressed files
- add a sysfs entry to manage ra_size given fadvise(POSIX_FADV_SEQUENTIAL)
- report f2fs GC status via sysfs
- add discard_unit=%s in mount option to handle zoned device
Bug fix:
- fix two memory leakages when an error happens in the compressed IO flow
- fix commpress_cache to get the right LBA
- fix fiemap to deal with compressed case correctly
- fix wrong EIO returns due to SBI_NEED_FSCK
- fix missing writes when enabling checkpoint back
- fix quota deadlock
- fix zstd level mount option
In addition to the above major updates, we've cleaned up several code paths such
as dio, unnecessary operations, debugfs/f2fs/status, sanity check, and typos.
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Merge tag 'f2fs-for-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this cycle, we've addressed some performance issues such as lock
contention, misbehaving compress_cache, allowing extent_cache for
compressed files, and new sysfs to adjust ra_size for fadvise.
In order to diagnose the performance issues quickly, we also added an
iostat which shows the IO latencies periodically.
On the stability side, we've found two memory leakage cases in the
error path in compression flow. And, we've also fixed various corner
cases in fiemap, quota, checkpoint=disable, zstd, and so on.
Enhancements:
- avoid long checkpoint latency by releasing nat_tree_lock
- collect and show iostats periodically
- support extent_cache for compressed files
- add a sysfs entry to manage ra_size given fadvise(POSIX_FADV_SEQUENTIAL)
- report f2fs GC status via sysfs
- add discard_unit=%s in mount option to handle zoned device
Bug fixes:
- fix two memory leakages when an error happens in the compressed IO flow
- fix commpress_cache to get the right LBA
- fix fiemap to deal with compressed case correctly
- fix wrong EIO returns due to SBI_NEED_FSCK
- fix missing writes when enabling checkpoint back
- fix quota deadlock
- fix zstd level mount option
In addition to the above major updates, we've cleaned up several code
paths such as dio, unnecessary operations, debugfs/f2fs/status, sanity
check, and typos"
* tag 'f2fs-for-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (46 commits)
f2fs: should put a page beyond EOF when preparing a write
f2fs: deallocate compressed pages when error happens
f2fs: enable realtime discard iff device supports discard
f2fs: guarantee to write dirty data when enabling checkpoint back
f2fs: fix to unmap pages from userspace process in punch_hole()
f2fs: fix unexpected ENOENT comes from f2fs_map_blocks()
f2fs: fix to account missing .skipped_gc_rwsem
f2fs: adjust unlock order for cleanup
f2fs: Don't create discard thread when device doesn't support realtime discard
f2fs: rebuild nat_bits during umount
f2fs: introduce periodic iostat io latency traces
f2fs: separate out iostat feature
f2fs: compress: do sanity check on cluster
f2fs: fix description about main_blkaddr node
f2fs: convert S_IRUGO to 0444
f2fs: fix to keep compatibility of fault injection interface
f2fs: support fault injection for f2fs_kmem_cache_alloc()
f2fs: compress: allow write compress released file after truncate to zero
f2fs: correct comment in segment.h
f2fs: improve sbi status info in debugfs/f2fs/status
...
Let's only enable realtime discard if and only if device supports
discard functionality.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We must flush all the dirty data when enabling checkpoint back. Let's guarantee
that first by adding a retry logic on sync_inodes_sb(). In addition to that,
this patch adds to flush data in fsync when checkpoint is disabled, which can
mitigate the sync_inodes_sb() failures in advance.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Don't create discard thread when device doesn't support realtime discard
or user specifies nodiscard mount option.
Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Whenever we notice some sluggish issues on our machines, we are always
curious about how well all types of I/O in the f2fs filesystem are
handled. But, it's hard to get this kind of real data. First of all,
we need to reproduce the issue while turning on the profiling tool like
blktrace, but the issue doesn't happen again easily. Second, with the
intervention of any tools, the overall timing of the issue will be
slightly changed and it sometimes makes us hard to figure it out.
So, I added the feature printing out IO latency statistics tracepoint
events, which are minimal things to understand filesystem's I/O related
behaviors, into F2FS_IOSTAT kernel config. With "iostat_enable" sysfs
node on, we can get this statistics info in a periodic way and it
would cause the least overhead.
[samples]
f2fs_ckpt-254:1-507 [003] .... 2842.439683: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [136/1/801], rd_node [136/1/1704], rd_meta [4/2/4],
wr_sync_data [164/16/3331], wr_sync_node [152/3/648],
wr_sync_meta [160/2/4243], wr_async_data [24/13/15],
wr_async_node [0/0/0], wr_async_meta [0/0/0]
f2fs_ckpt-254:1-507 [002] .... 2845.450514: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [60/3/456], rd_node [60/3/1258], rd_meta [0/0/1],
wr_sync_data [120/12/2285], wr_sync_node [88/5/428],
wr_sync_meta [52/6/2990], wr_async_data [4/1/3],
wr_async_node [0/0/0], wr_async_meta [0/0/0]
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
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>
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>
This patch fixes below problems of sb/cp sanity check:
- in sanity_check_raw_superi(), it missed to consider log header
blocks while cp_payload check.
- in f2fs_sanity_check_ckpt(), it missed to check nat_bits_blocks.
Cc: <stable@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
fadvise() allows the user to expand the readahead window to double with
POSIX_FADV_SEQUENTIAL, now. But, in some use cases, it is not that
sufficient and we need to meet the need in a restricted way. We can
control the multiplier value of bdi device readahead between 2 (default)
and 256 for POSIX_FADV_SEQUENTIAL advise option.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As James Z reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=213877
[1.] One-line summary of the problem:
Mount multiple SMR block devices exceed certain number cause system non-response
[2.] Full description of the problem/report:
Created some F2FS on SMR devices (mkfs.f2fs -m), then mounted in sequence. Each device is the same Model: HGST HSH721414AL (Size 14TB).
Empirically, found that when the amount of SMR device * 1.5Gb > System RAM, the system ran out of memory and hung. No dmesg output. For example, 24 SMR Disk need 24*1.5GB = 36GB. A system with 32G RAM can only mount 21 devices, the 22nd device will be a reproducible cause of system hang.
The number of SMR devices with other FS mounted on this system does not interfere with the result above.
[3.] Keywords (i.e., modules, networking, kernel):
F2FS, SMR, Memory
[4.] Kernel information
[4.1.] Kernel version (uname -a):
Linux 5.13.4-200.fc34.x86_64 #1 SMP Tue Jul 20 20:27:29 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
[4.2.] Kernel .config file:
Default Fedora 34 with f2fs-tools-1.14.0-2.fc34.x86_64
[5.] Most recent kernel version which did not have the bug:
None
[6.] Output of Oops.. message (if applicable) with symbolic information
resolved (see Documentation/admin-guide/oops-tracing.rst)
None
[7.] A small shell script or example program which triggers the
problem (if possible)
mount /dev/sdX /mnt/0X
[8.] Memory consumption
With 24 * 14T SMR Block device with F2FS
free -g
total used free shared buff/cache available
Mem: 46 36 0 0 10 10
Swap: 0 0 0
With 3 * 14T SMR Block device with F2FS
free -g
total used free shared buff/cache available
Mem: 7 5 0 0 1 1
Swap: 7 0 7
The root cause is, there are three bitmaps:
- cur_valid_map
- ckpt_valid_map
- discard_map
and each of them will cost ~500MB memory, {cur, ckpt}_valid_map are
necessary, but discard_map is optional, since this bitmap will only be
useful in mountpoint that small discard is enabled.
For a blkzoned device such as SMR or ZNS devices, f2fs will only issue
discard for a section(zone) when all blocks of that section are invalid,
so, for such device, we don't need small discard functionality at all.
This patch introduces a new mountoption "discard_unit=block|segment|
section" to support issuing discard with different basic unit which is
aligned to block, segment or section, so that user can specify
"discard_unit=segment" or "discard_unit=section" to disable small
discard functionality.
Note that this mount option can not be changed by remount() due to
related metadata need to be initialized during mount().
In order to save memory, let's use "discard_unit=section" for blkzoned
device by default.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In f2fs_remount(), return value of test_opt() is an unsigned int type
variable, however when we compare it to a bool type variable, it cause
wrong result, fix it.
Fixes: 4354994f09 ("f2fs: checkpoint disabling")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Use invalidate_lock instead of f2fs' private i_mmap_sem. The intended
purpose is exactly the same. By this conversion we fix a long standing
race between hole punching and read(2) / readahead(2) paths that can
lead to stale page cache contents.
CC: Jaegeuk Kim <jaegeuk@kernel.org>
CC: Chao Yu <yuchao0@huawei.com>
CC: linux-f2fs-devel@lists.sourceforge.net
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
When we create a directory with enable compression, all file write into
directory will try to compress.But sometimes we may know, new file
cannot meet compression ratio requirements.
We need a nocompress extension to skip those files to avoid unnecessary
compress page test.
After add nocompress_extension, the priority should be:
dir_flag < comp_extention,nocompress_extension < comp_file_flag,
no_comp_file_flag.
Priority in between FS_COMPR_FL, FS_NOCOMP_FS, extensions:
* compress_extension=so; nocompress_extension=zip; chattr +c dir;
touch dir/foo.so; touch dir/bar.zip; touch dir/baz.txt; then foo.so
and baz.txt should be compresse, bar.zip should be non-compressed.
chattr +c dir/bar.zip can enable compress on bar.zip.
* compress_extension=so; nocompress_extension=zip; chattr -c dir;
touch dir/foo.so; touch dir/bar.zip; touch dir/baz.txt; then foo.so
should be compresse, bar.zip and baz.txt should be non-compressed.
chattr+c dir/bar.zip; chattr+c dir/baz.txt; can enable compress on
bar.zip and baz.txt.
Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Add a slab cache: "f2fs_casefolded_name" for memory allocation
of casefold name.
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
Given RO feature in superblock, we don't need to check provisioning/reserve
spaces and SSA area.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Update the logging uses that have unnecessary newlines as the f2fs_printk
function and so its f2fs_<level> macro callers already adds one.
This allows searching single line logging entries with an easier grep and
also avoids unnecessary blank lines in the logging.
Miscellanea:
o Coalesce formats
o Align to open parenthesis
Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As marcosfrm reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=213089
Initramfs generators rely on "pre" softdeps (and "depends") to include
additional required modules.
F2FS does not declare "pre: crc32" softdep. Then every generator (dracut,
mkinitcpio...) has to maintain a hardcoded list for this purpose.
Hence let's use MODULE_SOFTDEP("pre: crc32") in f2fs code.
Fixes: 43b6573bac ("f2fs: use cryptoapi crc32 functions")
Reported-by: marcosfrm <marcosfrm@gmail.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As syzbot reported, there is an use-after-free issue during f2fs recovery:
Use-after-free write at 0xffff88823bc16040 (in kfence-#10):
kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is multi f2fs filesystem instances can race on accessing
global fsync_entry_slab pointer, result in use-after-free issue of slab
cache, fixes to init/destroy this slab cache only once during module
init/destroy procedure to avoid this issue.
Reported-by: syzbot+9d90dad32dd9727ed084@syzkaller.appspotmail.com
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this round, we added a new mount option, "checkpoint_merge", which introduces
a kernel thread dealing with the f2fs checkpoints. Once we start to manage the
IO priority along with blk-cgroup, the checkpoint operation can be processed in
a lower priority under the process context. Since the checkpoint holds all the
filesystem operations, we give a higher priority to the checkpoint thread all
the time.
Enhancement:
- introduce gc_merge mount option to introduce a checkpoint thread
- improve to run discard thread efficiently
- allow modular compression algorithms
- expose # of overprivision segments to sysfs
- expose runtime compression stat to sysfs
Bug fix:
- fix OOB memory access by the node id lookup
- avoid touching checkpointed data in the checkpoint-disabled mode
- fix the resizing flow to avoid kernel panic and race conditions
- fix block allocation issues on pinned files
- address some swapfile issues
- fix hugtask problem and kernel panic during atomic write operations
- don't start checkpoint thread in RO
And, we've cleaned up some kernel coding style and build warnings. In addition,
we fixed some minor race conditions and error handling routines.
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Merge tag 'f2fs-for-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we added a new mount option, "checkpoint_merge", which
introduces a kernel thread dealing with the f2fs checkpoints. Once we
start to manage the IO priority along with blk-cgroup, the checkpoint
operation can be processed in a lower priority under the process
context. Since the checkpoint holds all the filesystem operations, we
give a higher priority to the checkpoint thread all the time.
Enhancements:
- introduce gc_merge mount option to introduce a checkpoint thread
- improve to run discard thread efficiently
- allow modular compression algorithms
- expose # of overprivision segments to sysfs
- expose runtime compression stat to sysfs
Bug fixes:
- fix OOB memory access by the node id lookup
- avoid touching checkpointed data in the checkpoint-disabled mode
- fix the resizing flow to avoid kernel panic and race conditions
- fix block allocation issues on pinned files
- address some swapfile issues
- fix hugtask problem and kernel panic during atomic write operations
- don't start checkpoint thread in RO
And, we've cleaned up some kernel coding style and build warnings. In
addition, we fixed some minor race conditions and error handling
routines"
* tag 'f2fs-for-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (48 commits)
f2fs: drop inplace IO if fs status is abnormal
f2fs: compress: remove unneed check condition
f2fs: clean up left deprecated IO trace codes
f2fs: avoid using native allocate_segment_by_default()
f2fs: remove unnecessary struct declaration
f2fs: fix to avoid NULL pointer dereference
f2fs: avoid duplicated codes for cleanup
f2fs: document: add description about compressed space handling
f2fs: clean up build warnings
f2fs: fix the periodic wakeups of discard thread
f2fs: fix to avoid accessing invalid fio in f2fs_allocate_data_block()
f2fs: fix to avoid GC/mmap race with f2fs_truncate()
f2fs: set checkpoint_merge by default
f2fs: Fix a hungtask problem in atomic write
f2fs: fix to restrict mount condition on readonly block device
f2fs: introduce gc_merge mount option
f2fs: fix to cover __allocate_new_section() with curseg_lock
f2fs: fix wrong alloc_type in f2fs_do_replace_block
f2fs: delete empty compress.h
f2fs: fix a typo in inode.c
...
This patch combined the below three clean-up patches.
- modify open brace '{' following function definitions
- ERROR: spaces required around that ':'
- ERROR: spaces required before the open parenthesis '('
- ERROR: spaces prohibited before that ','
- Made suggested modifications from checkpatch in reference to WARNING:
Missing a blank line after declarations
Signed-off-by: Yi Zhuang <zhuangyi1@huawei.com>
Signed-off-by: Jia Yang <jiayang5@huawei.com>
Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Once we introduced checkpoint_merge, we've seen some contention w/o the option.
In order to avoid it, let's set it by default.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When we mount an unclean f2fs image in a readonly block device, let's
make mount() succeed only when there is no recoverable data in that
image, otherwise after mount(), file fsyned won't be recovered as user
expected.
Fixes: 938a184265 ("f2fs: give a warning only for readonly partition")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this patch, we will add two new mount options: "gc_merge" and
"nogc_merge", when background_gc is on, "gc_merge" option can be
set to let background GC thread to handle foreground GC requests,
it can eliminate the sluggish issue caused by slow foreground GC
operation when GC is triggered from a process with limited I/O
and CPU resources.
Original idea is from Xiang.
Signed-off-by: Gao Xiang <xiang@kernel.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In error path of f2fs_remount(), it missed to restart/stop kernel thread
or enable/disable checkpoint, then mount option status may not be
consistent with real condition of filesystem, so let's reorder remount
flow a bit as below and do recovery correctly in error path:
1) handle gc thread
2) handle ckpt thread
3) handle flush thread
4) handle checkpoint disabling
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In readonly mountpoint, there should be no write IOs include checkpoint
IO, so that it's not needed to create kernel checkpoint thread.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
LKP reports:
fs/f2fs/super.c:1516:20: warning: unused function 'f2fs_show_compress_options' [-Wunused-function]
static inline void f2fs_show_compress_options(struct seq_file *seq,
Fix this issue by covering f2fs_show_compress_options() with
CONFIG_F2FS_FS_COMPRESSION macro.
Fixes: 4c8ff7095b ("f2fs: support data compression")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
F2FS_IOC_FLUSH_DEVICE/F2FS_IOC_RESIZE_FS needs to migrate all blocks of
target segment to other place, no matter the segment has partially or fully
valid blocks.
However, after commit 803e74be04 ("f2fs: stop GC when the victim becomes
fully valid"), we may skip migration due to target segment is fully valid,
result in failing the ioctl interface, fix this.
Fixes: 803e74be04 ("f2fs: stop GC when the victim becomes fully valid")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been
horribly confusingly misnamed. Rename it to BIO_MAX_VECS to stop
confusing users of the bio API.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>