lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Sun, 17 Oct 2021 23:25:49 +0800
From:   Chao Yu <>
To:     Gao Xiang <>,
Cc:     LKML <>, Yue Hu <>,
        Gao Xiang <>
Subject: Re: [PATCH v2 1/3] erofs: get compression algorithms directly on

On 2021/10/9 4:08, Gao Xiang wrote:
> From: Gao Xiang <>
> Currently, z_erofs_map_blocks_iter() returns whether extents are
> compressed or not, and the decompression frontend gets the specific
> algorithms then.
> It works but not quite well in many aspests, for example:
>   - The decompression frontend has to deal with whether extents are
>     compressed or not again and lookup the algorithms if compressed.
>     It's duplicated and too detailed about the on-disk mapping.
>   - A new secondary compression head will be introduced later so that
>     each file can have 2 compression algorithms at most for different
>     type of data. It could increase the complexity of the decompression
>     frontend if still handled in this way;
>   - A new readmore decompression strategy will be introduced to get
>     better performance for much bigger pcluster and lzma, which needs
>     the specific algorithm in advance as well.
> Let's look up compression algorithms in z_erofs_map_blocks_iter()
> directly instead.
> Signed-off-by: Gao Xiang <>

Reviewed-by: Chao Yu <>


Powered by blists - more mailing lists