Re: [ndctl PATCH v3 1/6] libcxl: add GET_PARTITION_INFO mailbox command and accessors

[Alison Schofield <alison.schofield@intel.com>]

On Wed, Jan 26, 2022 at 08:07:17AM -0800, Dan Williams wrote:
> On Tue, Jan 18, 2022 at 12:20 PM <alison.schofield@intel.com> wrote:
> >
> > From: Alison Schofield <alison.schofield@intel.com>
> >
> > Users need access to the CXL GET_PARTITION_INFO mailbox command
> > to inspect and confirm changes to the partition layout of a memory
> > device.
> >
> > Add libcxl APIs to create a new GET_PARTITION_INFO mailbox command,
> > the command output data structure (privately), and accessor APIs to
> > return the different fields in the partition info output.
> >
> > Per the CXL 2.0 specification, devices report partition capacities
> > as multiples of 256MB. Define and use a capacity multiplier to
> > convert the raw data into bytes for user consumption. Use byte
> > format as the norm for all capacity values produced or consumed
> > using CXL Mailbox commands.
> >
> > Signed-off-by: Alison Schofield <alison.schofield@intel.com>
> 
> Looks good to me, you might want to also add a short note about the
> "cxl_cmd_new_get_partition_info()" API in the "=== MEMDEV: Commands"
> section of Documentation/cxl/lib/libcxl.txt that I started here:
> 
> https://lore.kernel.org/r/164298557771.3021641.14904324834528700206.stgit@dwillia2-desk3.amr.corp.intel.com

Will do.

> 
> Note that I'm not adding every single API there, but I think each
> cxl_cmd_new_<command_type>() API could use a short note.
> 
> That can be a follow on depending on whether Vishal merges this first
> or the topology enumeration series.

Vishal - I think this should follow the topology enumeration series
because it wants to use the cxl_filter_walk() that the topo series
introduces. (to spit out the updated partition info upon completion
of the set-partition-info cmd.)

So, a v4 posting will apply after topo series.

> 
> Reviewed-by: Dan Williams <dan.j.williams@intel.com>