From mboxrd@z Thu Jan 1 00:00:00 1970 From: keith.busch@intel.com (Busch, Keith) Date: Tue, 27 Oct 2015 22:36:43 +0000 Subject: [PATCH 0/5 v3] Fix NVMe driver support on Power with 32-bit DMA In-Reply-To: <20151027222010.GD7716@linux.vnet.ibm.com> References: <20151023205420.GA10197@linux.vnet.ibm.com> <20151026.182746.1323901353520152838.davem@davemloft.net> <20151027222010.GD7716@linux.vnet.ibm.com> Message-ID: <20151027223643.GA25332@localhost.localdomain> On Tue, Oct 27, 2015@03:20:10PM -0700, Nishanth Aravamudan wrote: > On 26.10.2015 [18:27:46 -0700], David Miller wrote: > > From: Nishanth Aravamudan > > Date: Fri, 23 Oct 2015 13:54:20 -0700 > > > > > 1) add a generic dma_get_page_shift implementation that just returns > > > PAGE_SHIFT > > > > I won't object to this patch series, but if I had implemented this I > > would have required the architectures to implement this explicitly, > > one-by-one. I think it is less error prone and more likely to end > > up with all the architectures setting this correctly. > > Well, looks like I should spin up a v4 anyways for the powerpc changes. > So, to make sure I understand your point, should I make the generic > dma_get_page_shift a compile-error kind of thing? It will only fail on > architectures that actually build the NVME driver (as the only caller). > But I'm not sure how exactly to achieve that, if you could give a bit > more detail I'd appreciate it! If you're suggesting to compile-time break architectures that currently work just fine with NVMe, let me stop you right there.