Commit Graph

36 Commits

Author SHA1 Message Date
Yue Hu fdffc091e6 erofs: support interlaced uncompressed data for compressed files
Currently, uncompressed data is all handled in the shifted way, which
means we have to shift the whole on-disk plain pcluster to get the
logical data.   However, since we are also using in-place I/O for
uncompressed data, data copy will be reduced a lot if pcluster is
recorded in the interlaced way as illustrated below:
 _______________________________________________________________
|               |    |               |_ tail part |_ head part _|
|<-   blk0    ->| .. |<-   blkn-2  ->|<-         blkn-1       ->|

The logical data then becomes:
 ________________________________________________________
|_ head part _|_  blk0  _| .. |_  blkn-2  _|_ tail part _|

In addition, non-4k plain pclusters are also survived by the
interlaced way, which can be used for non-4k lclusters as well.

However, it's almost impossible to de-duplicate uncompressed data
in the interlaced way, therefore shifted uncompressed data is still
useful.

Signed-off-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/8369112678604fdf4ef796626d59b1fdd0745a53.1663898962.git.huyue2@coolpad.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-23 10:55:56 +08:00
Gao Xiang 267f2492c8 erofs: introduce multi-reference pclusters (fully-referenced)
Let's introduce multi-reference pclusters at runtime. In details,
if one pcluster is requested by multiple extents at almost the same
time (even belong to different files), the longest extent will be
decompressed as representative and the other extents are actually
copied from the longest one in one round.

After this patch, fully-referenced extents can be correctly handled
and the full decoding check needs to be bypassed for
partial-referenced extents.

Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220715154203.48093-17-hsiangkao@linux.alibaba.com
2022-07-22 21:44:27 +08:00
Gao Xiang 448b5a1548 erofs: avoid consecutive detection for Highmem memory
Currently, vmap()s are avoided if physical addresses are
consecutive for decompressed buffers.

I observed that is very common for 4KiB pclusters since the
numbers of decompressed pages are almost 2 or 3.

However, such detection doesn't work for Highmem pages on
32-bit machines, let's fix it now.

Reported-by: Liu Jinbao <liujinbao1@xiaomi.com>
Fixes: 7fc45dbc93 ("staging: erofs: introduce generic decompression backend")
Link: https://lore.kernel.org/r/20220708101001.21242-1-hsiangkao@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-07-09 06:35:09 +08:00
Gao Xiang dcbe6803ff erofs: fix buffer copy overflow of ztailpacking feature
I got some KASAN report as below:

[   46.959738] ==================================================================
[   46.960430] BUG: KASAN: use-after-free in z_erofs_shifted_transform+0x2bd/0x370
[   46.960430] Read of size 4074 at addr ffff8880300c2f8e by task fssum/188
...
[   46.960430] Call Trace:
[   46.960430]  <TASK>
[   46.960430]  dump_stack_lvl+0x41/0x5e
[   46.960430]  print_report.cold+0xb2/0x6b7
[   46.960430]  ? z_erofs_shifted_transform+0x2bd/0x370
[   46.960430]  kasan_report+0x8a/0x140
[   46.960430]  ? z_erofs_shifted_transform+0x2bd/0x370
[   46.960430]  kasan_check_range+0x14d/0x1d0
[   46.960430]  memcpy+0x20/0x60
[   46.960430]  z_erofs_shifted_transform+0x2bd/0x370
[   46.960430]  z_erofs_decompress_pcluster+0xaae/0x1080

The root cause is that the tail pcluster won't be a complete filesystem
block anymore. So if ztailpacking is used, the second part of an
uncompressed tail pcluster may not be ``rq->pageofs_out``.

Fixes: ab749badf9 ("erofs: support unaligned data decompression")
Fixes: cecf864d3d ("erofs: support inline data decompression")
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20220512115833.24175-1-hsiangkao@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17 23:38:14 +08:00
Yue Hu 1e59af07c7 erofs: do not prompt for risk any more when using big pcluster
The big pcluster feature has been merged for a year, it has been mostly
stable now.

Signed-off-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/20220407050505.12683-1-huyue2@coolpad.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17 23:38:02 +08:00
Gao Xiang ab749badf9 erofs: support unaligned data decompression
Previously, compressed data was assumed as block-aligned. This
should be changed due to in-block tail-packing inline data.

Link: https://lore.kernel.org/r/20211228054604.114518-4-hsiangkao@linux.alibaba.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-12-31 00:48:43 +08:00
Gao Xiang 10e5f6e482 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>
2021-12-29 06:42:07 +08:00
Gao Xiang d67aee76d4 erofs: tidy up z_erofs_lz4_decompress
To prepare for the upcoming ztailpacking feature and further
cleanups, introduce a unique z_erofs_lz4_decompress_ctx to keep
the context, including inpages, outpages and oend, which are
frequently used by the lz4 decompressor.

No logic changes.

Link: https://lore.kernel.org/r/20211228054604.114518-2-hsiangkao@linux.alibaba.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-12-29 06:41:59 +08:00
Huang Jianan 7e508f2ca8 erofs: rename lz4_0pading to zero_padding
Renaming lz4_0padding to zero_padding globally since LZMA and later
algorithms also need that.

Link: https://lore.kernel.org/r/20211112160935.19394-1-jnhuang95@gmail.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-12-01 21:28:00 +08:00
Gao Xiang a0961f351d erofs: don't trigger WARN() when decompression fails
syzbot reported a WARNING [1] due to corrupted compressed data.

As Dmitry said, "If this is not a kernel bug, then the code should
not use WARN. WARN if for kernel bugs and is recognized as such by
all testing systems and humans."

[1] https://lore.kernel.org/r/000000000000b3586105cf0ff45e@google.com

Link: https://lore.kernel.org/r/20211025074311.130395-1-hsiangkao@linux.alibaba.com
Cc: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Reported-by: syzbot+d8aaffc3719597e8cfb4@syzkaller.appspotmail.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-10-31 21:00:28 +08:00
Gao Xiang eaa9172ad9 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>
2021-10-25 08:22:59 +08:00
Gao Xiang 622ceaddb7 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>
2021-10-19 23:44:30 +08:00
Gao Xiang 966edfb0a3 erofs: rename some generic methods in decompressor
Previously, some LZ4 methods were named with `generic'. However, while
evaluating the effective LZMA approach, it seems they aren't quite
generic at all (e.g. no need preparing dstpages for most LZMA cases.)

Avoid such naming instead.

Link: https://lore.kernel.org/r/20211010213145.17462-7-xiang@kernel.org
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-10-19 23:44:30 +08:00
Yue Hu 5b6e7e120e erofs: remove the fast path of per-CPU buffer decompression
As Xiang mentioned, such path has no real impact to our current
decompression strategy, remove it directly. Also, update the return
value of z_erofs_lz4_decompress() to 0 if success to keep consistent
with LZMA which will return 0 as well for that case.

Link: https://lore.kernel.org/r/20211014065744.1787-1-zbestahu@gmail.com
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-10-15 00:14:26 +08:00
Gao Xiang c5fcb51111 erofs: clean up file headers & footers
- Remove my outdated misleading email address;

 - Get rid of all unnecessary trailing newline by accident.

Link: https://lore.kernel.org/r/20210602160634.10757-1-xiang@kernel.org
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-06-08 00:41:24 +08:00
Gao Xiang 598162d050 erofs: support decompress big pcluster for lz4 backend
Prior to big pcluster, there was only one compressed page so it'd
easy to map this. However, when big pcluster is enabled, more work
needs to be done to handle multiple compressed pages. In detail,

 - (maptype 0) if there is only one compressed page + no need
   to copy inplace I/O, just map it directly what we did before;

 - (maptype 1) if there are more compressed pages + no need to
   copy inplace I/O, vmap such compressed pages instead;

 - (maptype 2) if inplace I/O needs to be copied, use per-CPU
   buffers for decompression then.

Another thing is how to detect inplace decompression is feasable or
not (it's still quite easy for non big pclusters), apart from the
inplace margin calculation, inplace I/O page reusing order is also
needed to be considered for each compressed page. Currently, if the
compressed page is the xth page, it shouldn't be reused as [0 ...
nrpages_out - nrpages_in + x], otherwise a full copy will be triggered.

Although there are some extra optimization ideas for this, I'd like
to make big pcluster work correctly first and obviously it can be
further optimized later since it has nothing with the on-disk format
at all.

Link: https://lore.kernel.org/r/20210407043927.10623-10-xiang@kernel.org
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-04-10 03:20:19 +08:00
Gao Xiang 4fea63f7d7 erofs: adjust per-CPU buffers according to max_pclusterblks
Adjust per-CPU buffers on demand since big pcluster definition is
available. Also, bail out unsupported pcluster size according to
Z_EROFS_PCLUSTER_MAX_SIZE.

Link: https://lore.kernel.org/r/20210407043927.10623-7-xiang@kernel.org
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-04-10 03:20:17 +08:00
Gao Xiang 524887347f erofs: introduce multipage per-CPU buffers
To deal the with the cases which inplace decompression is infeasible
for some inplace I/O. Per-CPU buffers was introduced to get rid of page
allocation latency and thrash for low-latency decompression algorithms
such as lz4.

For the big pcluster feature, introduce multipage per-CPU buffers to
keep such inplace I/O pclusters temporarily as well but note that
per-CPU pages are just consecutive virtually.

When a new big pcluster fs is mounted, its max pclustersize will be
read and per-CPU buffers can be growed if needed. Shrinking adjustable
per-CPU buffers is more complex (because we don't know if such size
is still be used), so currently just release them all when unloading.

Link: https://lore.kernel.org/r/20210409190630.19569-1-xiang@kernel.org
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-04-10 03:19:59 +08:00
Gao Xiang 14373711dd erofs: add on-disk compression configurations
Add a bitmap for available compression algorithms and a variable-sized
on-disk table for compression options in preparation for upcoming big
pcluster and LZMA algorithm, which follows the end of super block.

To parse the compression options, the bitmap is scanned one by one.
For each available algorithm, there is data followed by 2-byte `length'
correspondingly (it's enough for most cases, or entire fs blocks should
be used.)

With such available algorithm bitmap, kernel itself can also refuse to
mount such filesystem if any unsupported compression algorithm exists.

Note that COMPR_CFGS feature will be enabled with BIG_PCLUSTER.

Link: https://lore.kernel.org/r/20210329100012.12980-1-hsiangkao@aol.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-03-29 18:01:42 +08:00
Gao Xiang 46249cded1 erofs: introduce on-disk lz4 fs configurations
Introduce z_erofs_lz4_cfgs to store all lz4 configurations.
Currently it's only max_distance, but will be used for new
features later.

Link: https://lore.kernel.org/r/20210329012308.28743-4-hsiangkao@aol.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-03-29 10:24:58 +08:00
Huang Jianan 5d50538fc5 erofs: support adjust lz4 history window size
lz4 uses LZ4_DISTANCE_MAX to record history preservation. When
using rolling decompression, a block with a higher compression
ratio will cause a larger memory allocation (up to 64k). It may
cause a large resource burden in extreme cases on devices with
small memory and a large number of concurrent IOs. So appropriately
reducing this value can improve performance.

Decreasing this value will reduce the compression ratio (except
when input_size <LZ4_DISTANCE_MAX). But considering that erofs
currently only supports 4k output, reducing this value will not
significantly reduce the compression benefits.

The maximum value of LZ4_DISTANCE_MAX defined by lz4 is 64k, and
we can only reduce this value. For the old kernel, it just can't
reduce the memory allocation during rolling decompression without
affecting the decompression result.

Link: https://lore.kernel.org/r/20210329012308.28743-3-hsiangkao@aol.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Guo Weichao <guoweichao@oppo.com>
[ Gao Xiang: introduce struct erofs_sb_lz4_info for configurations. ]
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-03-29 10:24:58 +08:00
Gao Xiang de06a6a375 erofs: introduce erofs_sb_has_xxx() helpers
Introduce erofs_sb_has_xxx() to make long checks short, especially
for later big pcluster & LZMA features.

Link: https://lore.kernel.org/r/20210329012308.28743-2-hsiangkao@aol.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-03-29 10:24:57 +08:00
Huang Jianan b4892fa3e7 erofs: avoid memory allocation failure during rolling decompression
Currently, err would be treated as io error. Therefore, it'd be
better to ensure memory allocation during rolling decompression
to avoid such io error.

In the long term, we might consider adding another !Uptodate case
for such case.

Link: https://lore.kernel.org/r/20210316031515.90954-1-huangjianan@oppo.com
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Guo Weichao <guoweichao@oppo.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2021-03-29 10:18:00 +08:00
Gao Xiang 6aaa7b0664 erofs: get rid of magical Z_EROFS_MAPPING_STAGING
Previously, we played around with magical page->mapping for short-lived
temporary pages since we need to identify different types of pages in
the same pcluster but both invalidated and short-lived temporary pages
can have page->mapping == NULL. It was considered as safe because that
temporary pages are all non-LRU / non-movable pages.

This patch tends to use specific page->private to identify short-lived
pages instead so it won't rely on page->mapping anymore. Details are
described in "compress.h" as well.

Link: https://lore.kernel.org/r/20201208095834.3133565-1-hsiangkao@redhat.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2020-12-08 18:08:21 +08:00
Alexander A. Klimov 592e7cd00b erofs: Replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
	  If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
            If both the HTTP and HTTPS versions
            return 200 OK and serve the same content:
              Replace HTTP with HTTPS.

Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200713130944.34419-1-grandmaster@al2klimov.de
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
2020-08-03 21:04:29 +08:00
Christoph Hellwig d4efd79a81 mm: remove the prot argument from vm_map_ram
This is always PAGE_KERNEL - for long term mappings with other properties
vmap should be used.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-19-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 10:59:11 -07:00
Gao Xiang aa99a76b40 erofs: handle corrupted images whose decompressed size less than it'd be
As Lasse pointed out, "Looking at fs/erofs/decompress.c,
the return value from LZ4_decompress_safe_partial is only
checked for negative value to catch errors. ... So if
I understood it correctly, if there is bad data whose
uncompressed size is much less than it should be, it can
leave part of the output buffer untouched and expose the
previous data as the file content. "

Let's fix it now.

Cc: Lasse Collin <lasse.collin@tukaani.org>
Fixes: 7fc45dbc93 ("staging: erofs: introduce generic decompression backend")
[ Gao Xiang: v5.3+, I will manually backport this to stable later. ]
Link: https://lore.kernel.org/r/20200226081008.86348-3-gaoxiang25@huawei.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
2020-03-03 23:40:52 +08:00
Gao Xiang af1038abbd erofs: use LZ4_decompress_safe() for full decoding
As Lasse pointed out, "EROFS uses LZ4_decompress_safe_partial
for both partial and full blocks. Thus when it is decoding a
full block, it doesn't know if the LZ4 decoder actually decoded
all the input. The real uncompressed size could be bigger than
the value stored in the file system metadata.

Using LZ4_decompress_safe instead of _safe_partial when
decompressing a full block would help to detect errors."

So it's reasonable to use _safe in case of potential corrupted
images and it might have some speed gain as well although
I didn't observe much difference.

Note that legacy compressor (< 5.3, no LZ4_0PADDING) could
encode extra data in a pcluster, which is excluded as well.

Cc: Lasse Collin <lasse.collin@tukaani.org>
Fixes: 0ffd71bcc3 ("staging: erofs: introduce LZ4 decompression inplace")
[ Gao Xiang: v5.3+, I will manually backport this to stable later. ]
Link: https://lore.kernel.org/r/20200226081008.86348-2-gaoxiang25@huawei.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
2020-03-03 23:40:16 +08:00
Gao Xiang 4d2024370d erofs: fix out-of-bound read for shifted uncompressed block
rq->out[1] should be valid before accessing. Otherwise,
in very rare cases, out-of-bound dirty onstack rq->out[1]
can equal to *in and lead to unintended memmove behavior.

Link: https://lore.kernel.org/r/20200107022546.19432-1-gaoxiang25@huawei.com
Fixes: 7fc45dbc93 ("staging: erofs: introduce generic decompression backend")
Cc: <stable@vger.kernel.org> # 5.3+
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
2020-01-11 18:29:19 +08:00
Gao Xiang 5ddcee1f3a erofs: get rid of __stagingpage_alloc helper
Now open code is much cleaner due to iterative development.

Link: https://lore.kernel.org/r/20191124025217.12345-1-hsiangkao@aol.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
2019-11-24 10:57:48 +08:00
Gao Xiang 4f761fa253 erofs: rename errln/infoln/debugln to erofs_{err, info, dbg}
Add prefix "erofs_" to these functions and print
sb->s_id as a prefix to erofs_{err, info} so that
the user knows which file system is affected.

Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190904020912.63925-23-gaoxiang25@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 20:10:09 +02:00
Gao Xiang 73d03931be erofs: kill use_vmap module parameter
As Christoph said [1],
"vm_map_ram is supposed to generally behave better.  So if
it doesn't please report that that to the arch maintainer
and linux-mm so that they can look into the issue.  Having
user make choices of deep down kernel internals is just
a horrible interface.

Please talk to maintainers of other bits of the kernel
if you see issues and / or need enhancements. "

Let's redo the previous conclusion and kill the vmap
approach.

[1] https://lore.kernel.org/r/20190830165533.GA10909@infradead.org/
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190904020912.63925-21-gaoxiang25@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 20:10:09 +02:00
Gao Xiang 99634bf388 erofs: add "erofs_" prefix for common and short functions
Add erofs_ prefix to free_inode, alloc_inode, ...

Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190904020912.63925-19-gaoxiang25@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 20:10:08 +02:00
Gao Xiang 426a930891 erofs: use feature_incompat rather than requirements
As Christoph said [1], "This is only cosmetic, why
not stick to feature_compat and feature_incompat?"

In my thought, requirements means "incompatible"
instead of "feature" though.

[1] https://lore.kernel.org/r/20190902125109.GA9826@infradead.org/
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190904020912.63925-7-gaoxiang25@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 20:10:07 +02:00
Gao Xiang 8d8a09b093 erofs: remove all likely/unlikely annotations
As Dan Carpenter suggested [1], I have to remove
all erofs likely/unlikely annotations.

[1] https://lore.kernel.org/linux-fsdevel/20190829154346.GK23584@kadam/
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190829163827.203274-1-gaoxiang25@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-30 09:02:02 +02:00
Gao Xiang 47e4937a4a erofs: move erofs out of staging
EROFS filesystem has been merged into linux-staging for a year.

EROFS is designed to be a better solution of saving extra storage
space with guaranteed end-to-end performance for read-only files
with the help of reduced metadata, fixed-sized output compression
and decompression inplace technologies.

In the past year, EROFS was greatly improved by many people as
a staging driver, self-tested, betaed by a large number of our
internal users, successfully applied to almost all in-service
HUAWEI smartphones as the part of EMUI 9.1 and proven to be stable
enough to be moved out of staging.

EROFS is a self-contained filesystem driver. Although there are
still some TODOs to be more generic, we have a dedicated team
actively keeping on working on EROFS in order to make it better
with the evolution of Linux kernel as the other in-kernel filesystems.

As Pavel suggested, it's better to do as one commit since git
can do moves and all histories will be saved in this way.

Let's promote it from staging and enhance it more actively as
a "real" part of kernel for more wider scenarios!

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Pavel Machek <pavel@denx.de>
Cc: David Sterba <dsterba@suse.cz>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Darrick J . Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Richard Weinberger <richard@nod.at>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: Miao Xie <miaoxie@huawei.com>
Cc: Li Guifu <bluce.liguifu@huawei.com>
Cc: Fang Wei <fangwei1@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190822213659.5501-1-hsiangkao@aol.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-24 14:20:10 +02:00