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Date:   Tue, 9 Feb 2021 17:04:44 +0100 (CET)
From:   Richard Weinberger <richard@nod.at>
To:     Luca Risolia <luca.risolia@studio.unibo.it>
Cc:     Miklos Szeredi <miklos@szeredi.hu>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        fuse-devel <fuse-devel@lists.sourceforge.net>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Boris Brezillon <boris.brezillon@collabora.com>,
        linux-mtd <linux-mtd@lists.infradead.org>,
        Ron Minnich <rminnich@google.com>, sven <sven@narfation.org>
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Subject: Re: [fuse-devel] [PATCH 0/8] MUSE: Userspace backed MTD v3
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Thread-Topic: MUSE: Userspace backed MTD v3
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----- Ursprüngliche Mail -----
> for example, many existing video applications use mmap() to map the
> device memory to userspace memory. Adding support for mmap() to CUSE
> would allow these apps to work without any modifications with CUSE-based
>   device drivers other than kernel drivers.

So you want to access device memory via CUSE?
We have plenty of mechanisms in Linux to allow userspace accessing device memory.
E.g. /dev/mem, UIO, VFIO.

A simple (but ugly!) approach would be redirecting mmap() requests on CUSE devices to /dev/mem.
hmm?

Thanks,
//richard