Messages in this thread | | | Subject | Re: [PATCH] powerpc/mm: setting mmaped page cache property through device tree | From | Benjamin Herrenschmidt <> | Date | Fri, 04 Dec 2009 13:37:37 +1100 |
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On Tue, 2009-12-01 at 19:34 +0800, Li Yang wrote: > The scenario for the second case is to pre-allocate some memory to a > certain application or device (probably through mem=XXX kernel > parameter or limit through device tree). The memory is not known to > kernel, but fully managed by the application/device. We need being > able to map the region cachable for better performance. > > > trying to achieve here ? We can find a solution though it might > involve > > a specific driver to handle that memory. > > Right, but what the user to kernel API should be used? Is it ok to > use the O_SYNC flag as I previously proposed?
If it's cachable, why don't you write yourself a little driver that allocates memory maps it to userspace and provides you with the physical addresses and problem solved ?
Cheers, Ben.
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