For many use cases (e.g. container images are just fetched from remote),
performance will be impacted if underlay page cache is up-to-date but
direct i/o flushes dirty pages first.
Instead, let's use buffered I/O by default to keep in sync with loop
devices and add a (re)mount option to explicitly give a try to use
direct I/O if supported by the underlying files.
The container startup time is improved as below:
[workload] docker.io/library/workpress:latest
unpack 1st run non-1st runs
EROFS snapshotter buffered I/O file 4.586404265s 0.308s 0.198s
EROFS snapshotter direct I/O file 4.581742849s 2.238s 0.222s
EROFS snapshotter loop 4.596023152s 0.346s 0.201s
Overlayfs snapshotter 5.382851037s 0.206s 0.214s
Fixes: fb17675026 ("erofs: add file-backed mount support")
Cc: Derek McGowan <derek@mcg.dev>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241212134336.2059899-1-hsiangkao@linux.alibaba.com
Record `m_sb` and `m_dif` to replace `m_fscache`, `m_daxdev`, `m_fp`
and `m_dax_part_off` in order to simplify the codebase.
Note that `m_bdev` is still left since it can be assigned from
`sb->s_bdev` directly.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241212235401.2857246-1-hsiangkao@linux.alibaba.com
Instead of just listing each one directly in `struct erofs_sb_info`
except that we still use `sb->s_bdev` for the primary block device.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241216125310.930933-2-hsiangkao@linux.alibaba.com
Unify the common parts of erofs_fc_free() and erofs_kill_sb() as
erofs_sb_free().
Thus, fput() in erofs_fc_get_tree() is no longer needed, too.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241212133504.2047178-1-hsiangkao@linux.alibaba.com
There may still exist some pcluster with valid reference counts
during unmounting. Instead of introducing another synchronization
primitive, just try again as unmounting is relatively rare. This
approach is similar to z_erofs_cache_invalidate_folio().
It was also reported by syzbot as a UAF due to commit f5ad9f9a60
("erofs: free pclusters if no cached folio is attached"):
BUG: KASAN: slab-use-after-free in do_raw_spin_trylock+0x72/0x1f0 kernel/locking/spinlock_debug.c:123
..
queued_spin_trylock include/asm-generic/qspinlock.h:92 [inline]
do_raw_spin_trylock+0x72/0x1f0 kernel/locking/spinlock_debug.c:123
__raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline]
_raw_spin_trylock+0x20/0x80 kernel/locking/spinlock.c:138
spin_trylock include/linux/spinlock.h:361 [inline]
z_erofs_put_pcluster fs/erofs/zdata.c:959 [inline]
z_erofs_decompress_pcluster fs/erofs/zdata.c:1403 [inline]
z_erofs_decompress_queue+0x3798/0x3ef0 fs/erofs/zdata.c:1425
z_erofs_decompressqueue_work+0x99/0xe0 fs/erofs/zdata.c:1437
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
However, it seems a long outstanding memory leak. Fix it now.
Fixes: f5ad9f9a60 ("erofs: free pclusters if no cached folio is attached")
Reported-by: syzbot+7ff87b095e7ca0c5ac39@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/r/674c1235.050a0220.ad585.0032.GAE@google.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241203072821.1885740-1-hsiangkao@linux.alibaba.com
Adjust sb->s_blocksize{,_bits} directly for file-backed
mounts when the fs block size is smaller than PAGE_SIZE.
Previously, EROFS used sb_set_blocksize(), which caused
a panic if bdev-backed mounts is not used.
Fixes: fb17675026 ("erofs: add file-backed mount support")
Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241015103836.3757438-1-hongzhen@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
After commit 927e5010ff ("erofs: use kmap_local_page() only for
erofs_bread()"), `buf->kmap_type` actually has no use at all.
Let's get rid of `buf->kmap_type` now.
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241114095813.839866-1-hsiangkao@linux.alibaba.com
Add a sysfs node to drop compression-related caches, currently used to
drop in-memory pclusters and cached compressed folios.
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241113041148.749129-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Once a pcluster is fully decompressed and there are no attached cached
folios, its corresponding `struct z_erofs_pcluster` will be freed. This
will significantly reduce the frequency of calls to erofs_shrink_scan()
and the memory allocated for `struct z_erofs_pcluster`.
The tables below show approximately a 96% reduction in the calls to
erofs_shrink_scan() and in the memory allocated for `struct
z_erofs_pcluster` after applying this patch. The results were obtained
by performing a test to copy a 4.1GB partition on ARM64 Android devices
running the 6.6 kernel with an 8-core CPU and 12GB of memory.
1. The reduction in calls to erofs_shrink_scan():
+-----------------+-----------+----------+---------+
| | w/o patch | w/ patch | diff |
+-----------------+-----------+----------+---------+
| Average (times) | 11390 | 390 | -96.57% |
+-----------------+-----------+----------+---------+
2. The reduction in memory released by erofs_shrink_scan():
+-----------------+-----------+----------+---------+
| | w/o patch | w/ patch | diff |
+-----------------+-----------+----------+---------+
| Average (Byte) | 133612656 | 4434552 | -96.68% |
+-----------------+-----------+----------+---------+
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241112043235.546164-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
`struct erofs_workgroup` was introduced to provide a unique header
for all physically indexed objects. However, after big pclusters and
shared pclusters are implemented upstream, it seems that all EROFS
encoded data (which requires transformation) can be represented with
`struct z_erofs_pcluster` directly.
Move all members into `struct z_erofs_pcluster` for simplicity.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241021035323.3280682-3-hsiangkao@linux.alibaba.com
- Make sure only regular inodes can be used for file-backed mounts;
- Two minor codebase cleanups.
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Merge tag 'erofs-for-6.12-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs fixes from Gao Xiang:
"The main one fixes a syzbot issue due to the invalid inode type out of
file-backed mounts. The others are minor cleanups without actual logic
changes.
Summary:
- Make sure only regular inodes can be used for file-backed mounts
- Two minor codebase cleanups"
* tag 'erofs-for-6.12-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: get rid of kaddr in `struct z_erofs_maprecorder`
erofs: get rid of z_erofs_try_to_claim_pcluster()
erofs: ensure regular inodes for file-backed mounts
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
Negative i_size is never supported, although crafted images with inodes
having negative i_size will NOT lead to security issues in our current
codebase:
The following image can verify this (gzip+base64 encoded):
H4sICCmk4mYAA3Rlc3QuaW1nAGNgGAWjYBSMVPDo4dcH3jP2aTED2TwMKgxMUHHNJY/SQDQX
LxcDIw3tZwXit44MDNpQ/n8gQJZ/vxjijosPuSyZ0DUDgQqcZoKzVYFsDShbHeh6PT29ktTi
Eqz2g/y2pBFiLxDMh4lhs5+W4TAKRsEoGAWjYBSMglEwCkYBPQAAS2DbowAQAAA=
Mark as bad inodes for such corrupted inodes explicitly.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240912083538.3011860-1-hsiangkao@linux.alibaba.com
Error out if {en,de}encoded size of a pcluster is unsupported:
Maximum supported encoded size (of a pcluster): 1 MiB
Maximum supported decoded size (of a pcluster): 12 MiB
Users can still choose to use supported large configurations (e.g.,
for archival purposes), but there may be performance penalties in
low-memory scenarios compared to smaller pclusters.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240912074156.2925394-1-hsiangkao@linux.alibaba.com
This patch aims to allocate bvpages and short-lived compressed pages
from the reserved pool first.
After applying this patch, there are three benefits.
1. It reduces the page allocation time.
The bvpages and short-lived compressed pages account for about 4% of
the pages allocated from the system in the multi-app launch benchmarks
[1]. It reduces the page allocation time accordingly and lowers the
likelihood of blockage by page allocation in low memory scenarios.
2. The pages in the reserved pool will be allocated on demand.
Currently, bvpages and short-lived compressed pages are short-lived
pages allocated from the system, and the pages in the reserved pool all
originate from short-lived pages. Consequently, the number of reserved
pool pages will increase to z_erofs_rsv_nrpages over time.
With this patch, all short-lived pages are allocated from the reserved
pool first, so the number of reserved pool pages will only increase when
there are not enough pages. Thus, even if z_erofs_rsv_nrpages is set to
a large number for specific reasons, the actual number of reserved pool
pages may remain low as per demand. In the multi-app launch benchmarks
[1], z_erofs_rsv_nrpages is set at 256, while the number of reserved
pool pages remains below 64.
3. When erofs cache decompression is disabled
(EROFS_ZIP_CACHE_DISABLED), all pages will *only* be allocated from
the reserved pool for erofs. This will significantly reduce the memory
pressure from erofs.
[1] For additional details on the multi-app launch benchmarks, please
refer to commit 0f6273ab46 ("erofs: add a reserved buffer pool for lz4
decompression").
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20240906121110.3701889-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
With iterative development, our codebase can now deal with compressed
buffer misses properly if both in-place I/O and compressed buffer
allocation fail.
Note that if readahead fails (with non-uptodate folios), the original
request will then fall back to synchronous read, and `.read_folio()`
should return appropriate errnos; otherwise -EIO will be passed to
user space, which is unexpected.
To simplify rarely encountered failure paths, a mimic decompression
will be just used. Before that, failure reasons are recorded in
compressed_bvecs[] and they also act as placeholders to avoid in-place
pages. They will be parsed just before decompression and then pass
back to `.read_folio()`.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240905084732.2684515-1-hsiangkao@linux.alibaba.com
Get rid of redundant variables (nblocks, offset) and a dead branch
(!tailendpacking).
Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20240905030339.1474396-1-hongzhen@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Refactor out the iop binding behavior out of the erofs_fill_symlink
and move erofs_buf into the erofs_read_inode, so that erofs_fill_inode
can only deal with inode operation bindings and can be decoupled from
metabuf operations. This results in better calling conventions.
Note that after this patch, we do not need erofs_buf and ofs as
parameters any more when calling erofs_read_inode as
all the data operations are now included in itself.
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/all/20240425222847.GN2118490@ZenIV/
Signed-off-by: Yiyang Wu <toolmanp@tlmp.cc>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20240902093412.509083-1-toolmanp@tlmp.cc
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Although fscache is still described as "General Filesystem Caching" for
network filesystems and other things such as ISO9660 filesystems, it has
actually become a part of netfslib recently, which was unexpected at the
time when "EROFS over fscache" proposed (2021) since EROFS is entirely a
disk filesystem and the dependency is redundant.
Mark it deprecated and it will be removed after "fanotify pre-content
hooks" lands, which will provide the same functionality for EROFS.
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240830032840.3783206-4-hsiangkao@linux.alibaba.com
Use pseudo bios just like the previous fscache approach since
merged bio_vecs can be filled properly with unique interfaces.
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240830032840.3783206-3-hsiangkao@linux.alibaba.com
Since EROFS only needs to handle read requests in simple contexts,
Just directly use vfs_iocb_iter_read() for data I/Os.
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240905093031.2745929-1-hsiangkao@linux.alibaba.com
It actually has been around for years: For containers and other sandbox
use cases, there will be thousands (and even more) of authenticated
(sub)images running on the same host, unlike OS images.
Of course, all scenarios can use the same EROFS on-disk format, but
bdev-backed mounts just work well for OS images since golden data is
dumped into real block devices. However, it's somewhat hard for
container runtimes to manage and isolate so many unnecessary virtual
block devices safely and efficiently [1]: they just look like a burden
to orchestrators and file-backed mounts are preferred indeed. There
were already enough attempts such as Incremental FS, the original
ComposeFS and PuzzleFS acting in the same way for immutable fses. As
for current EROFS users, ComposeFS, containerd and Android APEXs will
be directly benefited from it.
On the other hand, previous experimental feature "erofs over fscache"
was once also intended to provide a similar solution (inspired by
Incremental FS discussion [2]), but the following facts show file-backed
mounts will be a better approach:
- Fscache infrastructure has recently been moved into new Netfslib
which is an unexpected dependency to EROFS really, although it
originally claims "it could be used for caching other things such as
ISO9660 filesystems too." [3]
- It takes an unexpectedly long time to upstream Fscache/Cachefiles
enhancements. For example, the failover feature took more than
one year, and the deamonless feature is still far behind now;
- Ongoing HSM "fanotify pre-content hooks" [4] together with this will
perfectly supersede "erofs over fscache" in a simpler way since
developers (mainly containerd folks) could leverage their existing
caching mechanism entirely in userspace instead of strictly following
the predefined in-kernel caching tree hierarchy.
After "fanotify pre-content hooks" lands upstream to provide the same
functionality, "erofs over fscache" will be removed then (as an EROFS
internal improvement and EROFS will not have to bother with on-demand
fetching and/or caching improvements anymore.)
[1] https://github.com/containers/storage/pull/2039
[2] https://lore.kernel.org/r/CAOQ4uxjbVxnubaPjVaGYiSwoGDTdpWbB=w_AeM6YM=zVixsUfQ@mail.gmail.com
[3] https://docs.kernel.org/filesystems/caching/fscache.html
[4] https://lore.kernel.org/r/cover.1723670362.git.josef@toxicpanda.com
Closes: https://github.com/containers/composefs/issues/144
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240830032840.3783206-1-hsiangkao@linux.alibaba.com
syzbot reported a task hang issue due to a deadlock case where it is
waiting for the folio lock of a cached folio that will be used for
cache I/Os.
After looking into the crafted fuzzed image, I found it's formed with
several overlapped big pclusters as below:
Ext: logical offset | length : physical offset | length
0: 0.. 16384 | 16384 : 151552.. 167936 | 16384
1: 16384.. 32768 | 16384 : 155648.. 172032 | 16384
2: 32768.. 49152 | 16384 : 537223168.. 537239552 | 16384
...
Here, extent 0/1 are physically overlapped although it's entirely
_impossible_ for normal filesystem images generated by mkfs.
First, managed folios containing compressed data will be marked as
up-to-date and then unlocked immediately (unlike in-place folios) when
compressed I/Os are complete. If physical blocks are not submitted in
the incremental order, there should be separate BIOs to avoid dependency
issues. However, the current code mis-arranges z_erofs_fill_bio_vec()
and BIO submission which causes unexpected BIO waits.
Second, managed folios will be connected to their own pclusters for
efficient inter-queries. However, this is somewhat hard to implement
easily if overlapped big pclusters exist. Again, these only appear in
fuzzed images so let's simply fall back to temporary short-lived pages
for correctness.
Additionally, it justifies that referenced managed folios cannot be
truncated for now and reverts part of commit 2080ca1ed3 ("erofs: tidy
up `struct z_erofs_bvec`") for simplicity although it shouldn't be any
difference.
Reported-by: syzbot+4fc98ed414ae63d1ada2@syzkaller.appspotmail.com
Reported-by: syzbot+de04e06b28cfecf2281c@syzkaller.appspotmail.com
Reported-by: syzbot+c8c8238b394be4a1087d@syzkaller.appspotmail.com
Tested-by: syzbot+4fc98ed414ae63d1ada2@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/r/0000000000002fda01061e334873@google.com
Fixes: 8e6c8fa9f2 ("erofs: enable big pcluster feature")
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240910070847.3356592-1-hsiangkao@linux.alibaba.com
If we get a failure at the first decompressor init (i = 0),
the clean up while loop could enter infinite loop due to wrong while
check. Check the value of i now to see if we need any clean up at all.
Fixes: 5a7cce827e ("erofs: refine z_erofs_{init,exit}_subsystem()")
Reported-by: liujinbao1 <liujinbao1@xiaomi.com>
Signed-off-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20240905060027.2388893-1-dhavale@google.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
After commit 684b290abc ("erofs: add support for
FS_IOC_GETFSSYSFSPATH"), `sb->s_sysfs_name` is now valid.
Just use it to get rid of duplicated logic.
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240828095232.571946-1-hsiangkao@linux.alibaba.com
Fast symlink can be used if the on-disk symlink data is stored
in the same block as the on-disk inode, so we don’t need to trigger
another I/O for symlink data. However, currently fs correction could be
reported _incorrectly_ if inode xattrs are too large.
In fact, these should be valid images although they cannot be handled as
fast symlinks.
Many thanks to Colin for reporting this!
Reported-by: Colin Walters <walters@verbum.org>
Reported-by: https://honggfuzz.dev/
Link: https://lore.kernel.org/r/bb2dd430-7de0-47da-ae5b-82ab2dd4d945@app.fastmail.com
Fixes: 431339ba90 ("staging: erofs: add inode operations")
[ Note that it's a runtime misbehavior instead of a security issue. ]
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240909031911.1174718-1-hsiangkao@linux.alibaba.com
If z_erofs_gbuf_growsize() partially fails on a global buffer due to
memory allocation failure or fault injection (as reported by syzbot [1]),
new pages need to be freed by comparing to the existing pages to avoid
memory leaks.
However, the old gbuf->pages[] array may not be large enough, which can
lead to null-ptr-deref or out-of-bound access.
Fix this by checking against gbuf->nrpages in advance.
[1] https://lore.kernel.org/r/000000000000f7b96e062018c6e3@google.com
Reported-by: syzbot+242ee56aaa9585553766@syzkaller.appspotmail.com
Fixes: d6db47e571 ("erofs: do not use pagepool in z_erofs_gbuf_growsize()")
Cc: <stable@vger.kernel.org> # 6.10+
Reviewed-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240820085619.1375963-1-hsiangkao@linux.alibaba.com
As commit 2e6506e1c4 ("mm/migrate: fix deadlock in
migrate_pages_batch() on large folios") has landed upstream, large
folios can be safely enabled for compressed inodes since all
prerequisites have already landed in 6.11-rc1.
Stress tests has been running on my fleet for over 20 days without any
regression. Additionally, users [1] have requested it for months.
Let's allow large folios for EROFS full cases upstream now for wider
testing.
[1] https://lore.kernel.org/r/CAGsJ_4wtE8OcpinuqVwG4jtdx6Qh5f+TON6wz+4HMCq=A2qFcA@mail.gmail.com
Cc: Barry Song <21cnbao@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
[ Gao Xiang: minor commit typo fixes. ]
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240819025207.3808649-1-hsiangkao@linux.alibaba.com
- Use i_size instead of i_size_read() due to immutable fses;
- Get rid of an unneeded goto since erofs_fill_dentries() also works;
- Remove unnecessary lines.
Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240801112622.2164029-1-hongzhen@linux.alibaba.com
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
FS_IOC_GETFSSYSFSPATH ioctl exposes /sys/fs path of a given filesystem,
potentially standarizing sysfs reporting. This patch add support for
FS_IOC_GETFSSYSFSPATH for erofs, "erofs/<dev>" will be outputted for bdev
cases, "erofs/[domain_id,]<fs_id>" will be outputted for fscache cases.
Signed-off-by: Huang Xiaojia <huangxiaojia2@huawei.com>
Link: https://lore.kernel.org/r/20240720082335.441563-1-huangxiaojia2@huawei.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Add support for STATX_DIOALIGN to EROFS, so that direct I/O
alignment restrictions are exposed to userspace in a generic
way.
[Before]
```
./statx_test /mnt/erofs/testfile
statx(/mnt/erofs/testfile) = 0
dio mem align:0
dio offset align:0
```
[After]
```
./statx_test /mnt/erofs/testfile
statx(/mnt/erofs/testfile) = 0
dio mem align:512
dio offset align:512
```
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240718083243.2485437-1-hsiangkao@linux.alibaba.com
Smatch complains that:
fs/erofs/zdata.c:1047 z_erofs_scan_folio()
error: uninitialized symbol 'err'.
The issue is if we hit this (!(map->m_flags & EROFS_MAP_MAPPED)) {
condition then "err" isn't set. It's inside a loop so we would have to
hit that condition on every iteration. Initialize "err" to zero to
solve this.
Fixes: 5b9654efb6 ("erofs: teach z_erofs_scan_folios() to handle multi-page folios")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/f78ab50e-ed6d-4275-8dd4-a4159fa565a2@stanley.mountain
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
LZ4 always reuses the decompressed buffer as its LZ77 sliding window
(dynamic dictionary) for optimal performance. However, in specific
cases, the output buffer may not fully contain valid page cache pages,
resulting in the use of short-lived pages for temporary purposes.
Due to the limited sliding window size, LZ4 shortlived bounce pages can
also be reused in a sliding manner, so each bounce page can be vmapped
multiple times in different relative positions by design. In order to
avoiding double frees, currently, reuse counts are recorded via page
refcount, but it will no longer be used as-is in the future world of
Memdescs.
Just maintain a lookup table to check if a shortlived page is reused.
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240711053659.1364989-1-hsiangkao@linux.alibaba.com
