Re: [Linux-nvdimm] [PATCH v2 08/20] libnd, nd_acpi: regions (block-data-window, persistent memory, volatile memory)

> -----Original Message----- > From: Linux-nvdimm [mailto:linux-nvdimm-bounces@lists.01.org] On Behalf Of > Dan Williams > Sent: Tuesday, April 28, 2015 1:25 PM > Subject: [Linux-nvdimm] [PATCH v2 08/20] libnd, nd_acpi: regions (block- > data-window, persistent memory, volatile memory) > > A "region" device represents the maximum capacity of a BLK range (mmio > block-data-window(s)), or a PMEM range (DAX-capable persistent memory or > volatile memory), without regard for aliasing. Aliasing, in the > dimm-local address space (DPA), is resolved by metadata on a dimm to > designate which exclusive interface will access the aliased DPA ranges. > Support for the per-dimm metadata/label arrvies is in a subsequent > patch. > > The name format of "region" devices is "regionN" where, like dimms, N is > a global ida index assigned at discovery time. This id is not reliable > across reboots nor in the presence of hotplug. Look to attributes of > the region or static id-data of the sub-namespace to generate a > persistent name. ... > +++ b/drivers/block/nd/region_devs.c ... > +static noinline struct nd_region *nd_region_create(struct nd_bus *nd_bus, > + struct nd_region_desc *ndr_desc, struct device_type *dev_type) > +{ > + struct nd_region *nd_region; > + struct device *dev; > + u16 i; > + > + for (i = 0; i < ndr_desc->num_mappings; i++) { > + struct nd_mapping *nd_mapping = &ndr_desc->nd_mapping[i]; > + struct nd_dimm *nd_dimm = nd_mapping->nd_dimm; > + > + if ((nd_mapping->start | nd_mapping->size) % SZ_4K) { > + dev_err(&nd_bus->dev, "%pf: %s mapping%d is not 4K > aligned\n", > + __builtin_return_address(0), Please use "KiB" rather than the unclear "K".

Same comment for a dev_dbg print in patch 14.

Could this include "nd" in the name, like "ndregion%d"? The other dev_set_name calls in this patch set use: btt%d ndbus%d nmem%d namespace%d.%d which are a bit more distinctive.