From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751918AbbEASHR (ORCPT ); Fri, 1 May 2015 14:07:17 -0400 Received: from g9t5009.houston.hp.com ([15.240.92.67]:56488 "EHLO g9t5009.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750913AbbEASHP (ORCPT ); Fri, 1 May 2015 14:07:15 -0400 Message-ID: <1430502493.23761.145.camel@misato.fc.hp.com> Subject: Re: [Linux-nvdimm] [PATCH v2 05/20] libnd, nd_acpi: dimm/memory-devices From: Toshi Kani To: Dan Williams Cc: linux-nvdimm@ml01.01.org, Neil Brown , Greg KH , "Rafael J. Wysocki" , Robert Moore , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org Date: Fri, 01 May 2015 11:48:13 -0600 In-Reply-To: <20150428182439.35812.81191.stgit@dwillia2-desk3.amr.corp.intel.com> References: <20150428181203.35812.60474.stgit@dwillia2-desk3.amr.corp.intel.com> <20150428182439.35812.81191.stgit@dwillia2-desk3.amr.corp.intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4 (3.10.4-4.fc20) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2015-04-28 at 14:24 -0400, Dan Williams wrote: > Register the memory devices described in the nfit as libnd 'dimm' > devices on an nd bus. The kernel assigned device id for dimms is > dynamic. If userspace needs a more static identifier it should consult > a provider-specific attribute. In the case where NFIT is the provider, > the 'nmemX/nfit/handle' or 'nmemX/nfit/serial' attributes may be used > for this purpose. : > + > +static int nd_acpi_register_dimms(struct acpi_nfit_desc *acpi_desc) > +{ > + struct nfit_mem *nfit_mem; > + > + list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) { > + struct nd_dimm *nd_dimm; > + unsigned long flags = 0; > + u32 nfit_handle; > + > + nfit_handle = __to_nfit_memdev(nfit_mem)->nfit_handle; > + nd_dimm = nd_acpi_dimm_by_handle(acpi_desc, nfit_handle); > + if (nd_dimm) { > + /* > + * If for some reason we find multiple DCRs the > + * first one wins > + */ > + dev_err(acpi_desc->dev, "duplicate DCR detected: %s\n", > + nd_dimm_name(nd_dimm)); > + continue; > + } > + > + if (nfit_mem->bdw && nfit_mem->memdev_pmem) > + flags |= NDD_ALIASING; Does this check work for a NVDIMM card which has multiple pmem regions with label info, but does not have any bdw region configured? The code assumes that namespace_pmem (NDD_ALIASING) and namespace_blk have label info. There may be an NVDIMM card with a single blk region without label info. Instead of using the namespace types to assume the label info, how about adding a flag to indicate the presence of the label info? This avoids the separation of namespace_io and namespace_pmem for the same pmem driver. Thanks, -Toshi