erofs: simplify compression configuration parser

[ Upstream commit efb4fb02cef3ab410b603c8f0e1c67f61d55f542 ]

Move erofs_load_compr_cfgs() into decompressor.c as well as introduce
a callback instea

erofs: simplify compression configuration parser

[ Upstream commit efb4fb02cef3ab410b603c8f0e1c67f61d55f542 ]

Move erofs_load_compr_cfgs() into decompressor.c as well as introduce
a callback instead of a hard-coded switch for each algorithm for
simplicity.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20231022130957.11398-1-xiang@kernel.org
Stable-dep-of: 118a8cf504d7 ("erofs: fix inconsistent per-file compression format")
Signed-off-by: Sasha Levin <sashal@kernel.org>

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erofs: fix memory leak of LZMA global compressed deduplication

When stressing microLZMA EROFS images with the new global compressed
deduplication feature enabled (`-Ededupe`), I found some short-liv

erofs: fix memory leak of LZMA global compressed deduplication

When stressing microLZMA EROFS images with the new global compressed
deduplication feature enabled (`-Ededupe`), I found some short-lived
temporary pages weren't properly released, which could slowly cause
unexpected OOMs hours later.

Let's fix it now (LZ4 and DEFLATE don't have this issue.)

Fixes: 5c2a64252c5d ("erofs: introduce partial-referenced pclusters")
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230907050542.97152-1-hsiangkao@linux.alibaba.com

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erofs: avoid hardcoded blocksize for subpage block support

As the first step of converting hardcoded blocksize to that specified in
on-disk superblock, convert all call sites of hardcoded blocksize

erofs: avoid hardcoded blocksize for subpage block support

As the first step of converting hardcoded blocksize to that specified in
on-disk superblock, convert all call sites of hardcoded blocksize to
sb->s_blocksize except for:

1) use sbi->blkszbits instead of sb->s_blocksize in
erofs_superblock_csum_verify() since sb->s_blocksize has not been
updated with the on-disk blocksize yet when the function is called.

2) use inode->i_blkbits instead of sb->s_blocksize in erofs_bread(),
since the inode operated on may be an anonymous inode in fscache mode.
Currently the anonymous inode is allocated from an anonymous mount
maintained in erofs, while in the near future we may allocate anonymous
inodes from a generic API directly and thus have no access to the
anonymous inode's i_sb. Thus we keep the block size in i_blkbits for
anonymous inodes in fscache mode.

Be noted that this patch only gets rid of the hardcoded blocksize, in
preparation for actually setting the on-disk block size in the following
patch. The hard limit of constraining the block size to PAGE_SIZE still
exists until the next patch.

Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20230313135309.75269-2-jefflexu@linux.alibaba.com
[ Gao Xiang: fold a patch to fix incorrect truncated offsets. ]
Link: https://lore.kernel.org/r/20230413035734.15457-1-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

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erofs: fix wrong kunmap when using LZMA on HIGHMEM platforms

As the call trace shown, the root cause is kunmap incorrect pages:

BUG: kernel NULL pointer dereference, address: 00000000
CPU: 1 PID:

erofs: fix wrong kunmap when using LZMA on HIGHMEM platforms

As the call trace shown, the root cause is kunmap incorrect pages:

BUG: kernel NULL pointer dereference, address: 00000000
CPU: 1 PID: 40 Comm: kworker/u5:0 Not tainted 6.2.0-rc5 #4
Workqueue: erofs_worker z_erofs_decompressqueue_work
EIP: z_erofs_lzma_decompress+0x34b/0x8ac
z_erofs_decompress+0x12/0x14
z_erofs_decompress_queue+0x7e7/0xb1c
z_erofs_decompressqueue_work+0x32/0x60
process_one_work+0x24b/0x4d8
? process_one_work+0x1a4/0x4d8
worker_thread+0x14c/0x3fc
kthread+0xe6/0x10c
? rescuer_thread+0x358/0x358
? kthread_complete_and_exit+0x18/0x18
ret_from_fork+0x1c/0x28
---[ end trace 0000000000000000 ]---

The bug is trivial and should be fixed now. It has no impact on
!HIGHMEM platforms.

Fixes: 622ceaddb764 ("erofs: lzma compression support")
Cc: <stable@vger.kernel.org> # 5.16+
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230305134455.88236-1-hsiangkao@linux.alibaba.com

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erofs: mark z_erofs_lzma_init/erofs_pcpubuf_init w/ __init

They are used during the erofs module init phase. Let's mark it as
__init like any other function.

Signed-off-by: Yangtao Li <frank.li@viv

erofs: mark z_erofs_lzma_init/erofs_pcpubuf_init w/ __init

They are used during the erofs module init phase. Let's mark it as
__init like any other function.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20230303063731.66760-1-frank.li@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

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erofs: introduce partial-referenced pclusters

Due to deduplication for compressed data, pclusters can be partially
referenced with their prefixes.

Together with the user-space implementation, it en

erofs: introduce partial-referenced pclusters

Due to deduplication for compressed data, pclusters can be partially
referenced with their prefixes.

Together with the user-space implementation, it enables EROFS
variable-length global compressed data deduplication with rolling
hash.

Link: https://lore.kernel.org/r/20220923014915.4362-1-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

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erofs: wake up all waiters after z_erofs_lzma_head ready

When the user mounts the erofs second times, the decompression thread
may hung. The problem happens due to a sequence of steps like the
follo

erofs: wake up all waiters after z_erofs_lzma_head ready

When the user mounts the erofs second times, the decompression thread
may hung. The problem happens due to a sequence of steps like the
following:

1) Task A called z_erofs_load_lzma_config which obtain all of the node
from the z_erofs_lzma_head.

2) At this time, task B called the z_erofs_lzma_decompress and wanted to
get a node. But the z_erofs_lzma_head was empty, the Task B had to
sleep.

3) Task A release nodes and push nodes into the z_erofs_lzma_head. But
task B was still sleeping.

One example report when the hung happens:
task:kworker/u3:1 state:D stack:14384 pid: 86 ppid: 2 flags:0x00004000
Workqueue: erofs_unzipd z_erofs_decompressqueue_work
Call Trace:
<TASK>
__schedule+0x281/0x760
schedule+0x49/0xb0
z_erofs_lzma_decompress+0x4bc/0x580
? cpu_core_flags+0x10/0x10
z_erofs_decompress_pcluster+0x49b/0xba0
? __update_load_avg_se+0x2b0/0x330
? __update_load_avg_se+0x2b0/0x330
? update_load_avg+0x5f/0x690
? update_load_avg+0x5f/0x690
? set_next_entity+0xbd/0x110
? _raw_spin_unlock+0xd/0x20
z_erofs_decompress_queue.isra.0+0x2e/0x50
z_erofs_decompressqueue_work+0x30/0x60
process_one_work+0x1d3/0x3a0
worker_thread+0x45/0x3a0
? process_one_work+0x3a0/0x3a0
kthread+0xe2/0x110
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x22/0x30
</TASK>

Signed-off-by: Yuwen Chen <chenyuwen1@meizu.com>
Fixes: 622ceaddb764 ("erofs: lzma compression support")
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220626224041.4288-1-chenyuwen1@meizu.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

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erofs: introduce z_erofs_fixup_insize

To prepare for the upcoming ztailpacking feature, introduce
z_erofs_fixup_insize() and pageofs_in to wrap up the process
to get the exact compressed size via ze

erofs: introduce z_erofs_fixup_insize

To prepare for the upcoming ztailpacking feature, introduce
z_erofs_fixup_insize() and pageofs_in to wrap up the process
to get the exact compressed size via zero padding.

Link: https://lore.kernel.org/r/20211228054604.114518-3-hsiangkao@linux.alibaba.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

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erofs: get rid of ->lru usage

Currently, ->lru is a way to arrange non-LRU pages and has some
in-kernel users. In order to minimize noticable issues of page
reclaim and cache thrashing under high me

erofs: get rid of ->lru usage

Currently, ->lru is a way to arrange non-LRU pages and has some
in-kernel users. In order to minimize noticable issues of page
reclaim and cache thrashing under high memory presure, limited
temporary pages were all chained with ->lru and can be reused
during the request. However, it seems that ->lru could be removed
when folio is landing.

Let's use page->private to chain temporary pages for now instead
and transform EROFS formally after the topic of the folio / file
page design is finalized.

Link: https://lore.kernel.org/r/20211022090120.14675-1-hsiangkao@linux.alibaba.com
Cc: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

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erofs: lzma compression support

Add MicroLZMA support in order to maximize compression ratios for
specific scenarios. For example, it's useful for low-end embedded
boards and as a secondary algorith

erofs: lzma compression support

Add MicroLZMA support in order to maximize compression ratios for
specific scenarios. For example, it's useful for low-end embedded
boards and as a secondary algorithm in a file for specific access
patterns.

MicroLZMA is a new container format for raw LZMA1, which was created
by Lasse Collin aiming to minimize old LZMA headers and get rid of
unnecessary EOPM (end of payload marker) as well as to enable
fixed-sized output compression, especially for 4KiB pclusters.

Similar to LZ4, inplace I/O approach is used to minimize runtime
memory footprint when dealing with I/O. Overlapped decompression is
handled with 1) bounced buffer for data under processing or 2) extra
short-lived pages from the on-stack pagepool which will be shared in
the same read request (128KiB for example).

Link: https://lore.kernel.org/r/20211010213145.17462-8-xiang@kernel.org
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

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