From: linux@armlinux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: Creating kernel mappings for memory initially marked with bootmem NOMAP?
Date: Wed, 8 Mar 2017 19:29:28 +0000 [thread overview]
Message-ID: <20170308192928.GC21222@n2100.armlinux.org.uk> (raw)
In-Reply-To: <20170308192653.GB21222@n2100.armlinux.org.uk>
On Wed, Mar 08, 2017 at 07:26:53PM +0000, Russell King - ARM Linux wrote:
> On Wed, Mar 08, 2017 at 11:03:43AM -0800, Florian Fainelli wrote:
> > Now, we have some peripherals that want large chunks of physically and
> > virtually contiguous memory that belong to these memblock NOMAP ranges.
> > I have no problems using mmap() against this memory, because the kernel
> > will do what is necessary for a process to map it for me. The struggle
> > is for a kernel driver which specifies a range of physical memory and
> > size, and expects a virtually contiguous mapping in return (not using
> > DMA-API, because reasons).
>
> Will vm_iomap_memory() do the job?
Sorry, I thought you were asking about userspace. The memremap()
family of functions is what you want for mapping it into the kernel.
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prev parent reply other threads:[~2017-03-08 19:29 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-08 19:03 Creating kernel mappings for memory initially marked with bootmem NOMAP? Florian Fainelli
2017-03-08 19:14 ` Ard Biesheuvel
2017-03-08 19:52 ` Florian Fainelli
2017-03-08 22:06 ` Ard Biesheuvel
2017-03-08 22:10 ` Florian Fainelli
2017-03-16 19:04 ` Florian Fainelli
2017-03-16 20:00 ` Russell King - ARM Linux
2017-03-08 19:26 ` Russell King - ARM Linux
2017-03-08 19:29 ` Russell King - ARM Linux [this message]
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