Re: [PATCH] firmware: remove request_firmware_into_buf()

[Alan Cox]

On Mon, 2017-06-26 at 13:22 -0700, Bjorn Andersson wrote:
> On Fri, Jun 23, 2017 at 9:03 AM, Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > 
> > As Luis pointed out, there are no in-kernel users of
> > request_firmware_into_buf(), so remove it, and the now unused
> > internal
> > flag, which simplifies the logic around buffer handling a bit.
> > 
> 
> This API was implemented to reduce the memory pressure during
> firmware
> load in the Qualcomm remoteprocs, but it wasn't available when I
> upstreamed that code and I apparently forgot to send out the patch
> moving us over to use this API...
> 
> Especially when loading the Qualcomm modem we have a couple of files
> that we request_firmware() that are 10-15MB in size, so this
> functionality is definitely wanted.

It may also at some point be very useful for FPGA partial reprogramming
- the FPGA bitstreams are *not* small and most FPGAs you don't need all
of it in kernel memory at the same moment.

Alan