Creating kernel mappings for memory initially marked with bootmem NOMAP?

Russell King - ARM Linux linux at armlinux.org.uk
Wed Mar 8 11:26:53 PST 2017


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?

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