Re: [PATCH v8 09/10] nvdimm: sysfs shows which dsm support full command ioctl.

On Mon, Apr 11, 2016 at 4:58 PM, Jerry Hoemann <jerry.hoemann(a)hpe.com&gt; wrote: > On Mon, Apr 11, 2016 at 02:43:39PM -0700, Dan Williams wrote: >> On Mon, Mar 21, 2016 at 12:37 PM, Jerry Hoemann <jerry.hoemann(a)hpe.com&gt; wrote: >> > NVDIMM DSMs whose functions map to the Intel Example DSM, can >> > be called with the ND_IOCTL_.* ioctl interface. Those that >> > don't map, can only be called with the pass thru command. >> > >> > Save this indication in struct nvdimm to be passed to >> > the sysfs interface. >> > >> >> I'm having trouble understanding the intent of cmd_ioctl. I don't >> want a flag for "supports Intel Example DSM", I want a mask of ND >> commands the bus provider knows how to handle in its ->ndctl() entry >> point for the given dimm. The bus provider is free to provide a >> translation of ND command to the bus specific command. It's just an >> arbitrary coincidence that the current list of ND commands matches the >> Intel ACPI _DSM command format. > > This is my extension of your earlier RFC patch, so I may > have misunderstood your original intent. > > The commands_show functions prints the listing of commands for that device. > There is one version for root, and one version for non-root. > > For root commands, both dsm spec match on names and semantics, so no > code works for both nvdimms types. > > But for non-root commands the names/semantics don't match. So, this > is an attempt to show that on an NVDIMM-N, only the pass thru command > is supported. Ah, ok. Rather than telling the core about a dsm_mask and a cmd_ioctl at nvdimm_create() time, it should just be passing the mask of generic ND commands that the dimm supports. For NVDIMM-N that mask will just be (1 << 10) it's up to the nfit driver to manage any ND command to ACPI _DSM command number translation.