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:   Wed, 6 Sep 2017 06:47:31 -0700
From:   Christoph Hellwig <>
To:     Javier González <>
        Javier González <>,
        Matias Bjørling <>
Subject: Re: [PATCH 10/18] lightnvm: pblk: use bio_copy_kern when possible

On Wed, Sep 06, 2017 at 12:51:03PM +0200, Javier González wrote:
> In pblk, buffers forming bios can be allocated on physically contiguous
> or virtually contiguous memory. For physically contiguous memory, we
> already use the bio_map_kern helper funciton, however, for virtually
> contiguous memory, we from the bio manually. This makes the code more
> complex, specially on the completion path, where mapped pages need to be
> freed.
> Instead, use bio_copy_kern, which does the same and at the same time
> simplifies the completion path.

Nope.  You want to loop over vmalloc_to_page and call bio_add_page
for each page, after taking care of virtually tagged caches instead
of this bounce buffering.

And you really want to allocate the request first and only then map
the data to the request, as said before.

Powered by blists - more mailing lists