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| author | Gao Xiang <hsiangkao@linux.alibaba.com> | 2023-08-10 18:48:59 +0300 |
|---|---|---|
| committer | Gao Xiang <hsiangkao@linux.alibaba.com> | 2023-08-11 07:11:17 +0300 |
| commit | ffa09b3bd02427ab631f0c1b64714ce6fc885f61 (patch) | |
| tree | 7b872de63b71a6e3c99c07a7dbd832955f3f35c2 /fs/erofs/internal.h | |
| parent | 52a93d39b17dc7eb98b6aa3edb93943248e03b2f (diff) | |
| download | linux-ffa09b3bd02427ab631f0c1b64714ce6fc885f61.tar.xz | |
erofs: DEFLATE compression support
Add DEFLATE compression as the 3rd supported algorithm.
DEFLATE is a popular generic-purpose compression algorithm for quite
long time (many advanced formats like gzip, zlib, zip, png are all
based on that) as Apple documentation written "If you require
interoperability with non-Apple devices, use COMPRESSION_ZLIB. [1]".
Due to its popularity, there are several hardware on-market DEFLATE
accelerators, such as (s390) DFLTCC, (Intel) IAA/QAT, (HiSilicon) ZIP
accelerator, etc. In addition, there are also several high-performence
IP cores and even open-source FPGA approches available for DEFLATE.
Therefore, it's useful to support DEFLATE compression in order to find
a way to utilize these accelerators for asynchronous I/Os and get
benefits from these later.
Besides, it's a good choice to trade off between compression ratios
and performance compared to LZ4 and LZMA. The DEFLATE core format is
simple as well as easy to understand, therefore the code size of its
decompressor is small even for the bootloader use cases. The runtime
memory consumption is quite limited too (e.g. 32K + ~7K for each zlib
stream). As usual, EROFS ourperforms similar approaches too.
Alternatively, DEFLATE could still be used for some specific files
since EROFS supports multiple compression algorithms in one image.
[1] https://developer.apple.com/documentation/compression/compression_algorithm
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230810154859.118330-1-hsiangkao@linux.alibaba.com
Diffstat (limited to 'fs/erofs/internal.h')
| -rw-r--r-- | fs/erofs/internal.h | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 36e32fa542f0..fb45855cfd5d 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -519,6 +519,26 @@ static inline int z_erofs_load_lzma_config(struct super_block *sb, } #endif /* !CONFIG_EROFS_FS_ZIP_LZMA */ +#ifdef CONFIG_EROFS_FS_ZIP_DEFLATE +int __init z_erofs_deflate_init(void); +void z_erofs_deflate_exit(void); +int z_erofs_load_deflate_config(struct super_block *sb, + struct erofs_super_block *dsb, + struct z_erofs_deflate_cfgs *dfl, int size); +#else +static inline int z_erofs_deflate_init(void) { return 0; } +static inline int z_erofs_deflate_exit(void) { return 0; } +static inline int z_erofs_load_deflate_config(struct super_block *sb, + struct erofs_super_block *dsb, + struct z_erofs_deflate_cfgs *dfl, int size) { + if (dfl) { + erofs_err(sb, "deflate algorithm isn't enabled"); + return -EINVAL; + } + return 0; +} +#endif /* !CONFIG_EROFS_FS_ZIP_DEFLATE */ + #ifdef CONFIG_EROFS_FS_ONDEMAND int erofs_fscache_register_fs(struct super_block *sb); void erofs_fscache_unregister_fs(struct super_block *sb); |