Re: [PATCH v4 1/3] Documentatiion/ABI: Add ABI documentation for sys-bus-dax

From: Jonathan Cameron
Date: Wed Dec 13 2023 - 11:51:02 EST


On Tue, 12 Dec 2023 12:08:30 -0700
Vishal Verma <vishal.l.verma@xxxxxxxxx> wrote:

> Add the missing sysfs ABI documentation for the device DAX subsystem.
> Various ABI attributes under this have been present since v5.1, and more
> have been added over time. In preparation for adding a new attribute,
> add this file with the historical details.
>
> Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> Signed-off-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>

Hi Vishal, One editorial suggestions.

I don't know the interface well enough to do a good review of the content
so leaving that for Dan or others.

> +What: /sys/bus/dax/devices/daxX.Y/mapping[0..N]/start
> +Date: October, 2020
> +KernelVersion: v5.10
> +Contact: nvdimm@xxxxxxxxxxxxxxx
> +Description:
> + (RO) A dax device may have multiple constituent discontiguous
> + address ranges. These are represented by the different
> + 'mappingX' subdirectories. The 'start' attribute indicates the
> + start physical address for the given range.

A common option for these files is to have a single entry with two What:
lines. Here that would avoid duplication of majority of this text across
the start, end and page_offset entries. Alternatively you could do an
entry for the mapping[0..N] directory with the shared text then separate
entries for the 3 files under there.


> +
> +What: /sys/bus/dax/devices/daxX.Y/mapping[0..N]/end
> +Date: October, 2020
> +KernelVersion: v5.10
> +Contact: nvdimm@xxxxxxxxxxxxxxx
> +Description:
> + (RO) A dax device may have multiple constituent discontiguous
> + address ranges. These are represented by the different
> + 'mappingX' subdirectories. The 'end' attribute indicates the
> + end physical address for the given range.
> +
> +What: /sys/bus/dax/devices/daxX.Y/mapping[0..N]/page_offset
> +Date: October, 2020
> +KernelVersion: v5.10
> +Contact: nvdimm@xxxxxxxxxxxxxxx
> +Description:
> + (RO) A dax device may have multiple constituent discontiguous
> + address ranges. These are represented by the different
> + 'mappingX' subdirectories. The 'page_offset' attribute indicates the
> + offset of the current range in the dax device.