Re: [PATCH v2 1/4] erofs: add file-backed mount support

From: Gao Xiang
Date: Fri Aug 30 2024 - 23:00:39 EST


Hi Sandeep,

On 2024/8/31 08:30, Sandeep Dhavale via Linux-erofs wrote:
On Thu, Aug 29, 2024 at 8:29 PM Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx> wrote:

It actually has been around for years: For containers and other sandbox
use cases, there will be thousands (and even more) of authenticated
(sub)images running on the same host, unlike OS images.

Of course, all scenarios can use the same EROFS on-disk format, but
bdev-backed mounts just work well for OS images since golden data is
dumped into real block devices. However, it's somewhat hard for
container runtimes to manage and isolate so many unnecessary virtual
block devices safely and efficiently [1]: they just look like a burden
to orchestrators and file-backed mounts are preferred indeed. There
were already enough attempts such as Incremental FS, the original
ComposeFS and PuzzleFS acting in the same way for immutable fses. As
for current EROFS users, ComposeFS, containerd and Android APEXs will
be directly benefited from it.

Hi Gao,
Thank you for the series! This is an interesting idea and will
definitely help the Android ecosystem for APEXes if we can remove the
loopback device. I will take a deeper look and provide comments soon.

Yes, I've seen no issue so far, and it will be submited for 6.12
since there are many users which really need this and wait for it.

Thanks,
Gao Xiang