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Subject: Re: [PATCH v6 0/3] ubi: Add block interface
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Date: Mon, 17 Feb 2014 12:19:52 +0200
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Thanks!

On Sun, 2014-02-16 at 17:03 -0300, Ezequiel Garcia wrote:
> The main target of this patch is supporting lighter, read-only
> filesystem,
> by putting a squashfs on top of ubiblock. And since squashfs already
> provides
> a file cache (which is even configurable), a first uncached
> implementation
> it's good enough for now.

Doesn't Linux provide a fake inode for _every_ block device, and uses
page-cache to cache pages?

There is even entire special-purpose file-system for managing these fake
block device inodes, see fs/block_dev.c

static struct file_system_type bd_type = {
        .name           = "bdev",
        .mount          = bd_mount,
        .kill_sb        = kill_anon_super,
};

I am really not sure which other cache do we need. The only thing coming
to my mind is about emulating a HW disk cache in software. But I would
not go that far without a really good reason.

If what I say is correct, I guess we can just drop the "cache" subject
completely now.

-- 
Best Regards,
Artem Bityutskiy