On Mon, 07 Oct 2024 18:16:28 -0500 ira.weiny@xxxxxxxxx wrote: > From: Navneet Singh <navneet.singh@xxxxxxxxx> > > Extent information can be helpful to the user to coordinate memory usage > with the external orchestrator and FM. > > Expose the details of region extents by creating the following > sysfs entries. > > /sys/bus/cxl/devices/dax_regionX/extentX.Y > /sys/bus/cxl/devices/dax_regionX/extentX.Y/offset > /sys/bus/cxl/devices/dax_regionX/extentX.Y/length > /sys/bus/cxl/devices/dax_regionX/extentX.Y/tag > > Signed-off-by: Navneet Singh <navneet.singh@xxxxxxxxx> > Co-developed-by: Ira Weiny <ira.weiny@xxxxxxxxx> > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> > Trivial comments inline. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > --- > Changes: > [djiang: Split sysfs docs up] > [iweiny: Adjust sysfs docs dates] > --- > Documentation/ABI/testing/sysfs-bus-cxl | 32 ++++++++++++++++++ > drivers/cxl/core/extent.c | 58 +++++++++++++++++++++++++++++++++ > 2 files changed, 90 insertions(+) > > diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl > index b63ab622515f..64918180a3c9 100644 > --- a/Documentation/ABI/testing/sysfs-bus-cxl > +++ b/Documentation/ABI/testing/sysfs-bus-cxl > @@ -632,3 +632,35 @@ Description: > See Documentation/ABI/stable/sysfs-devices-node. access0 provides > the number to the closest initiator and access1 provides the > number to the closest CPU. > + > +What: /sys/bus/cxl/devices/dax_regionX/extentX.Y/offset > +Date: December, 2024 > +KernelVersion: v6.13 > +Contact: linux-cxl@xxxxxxxxxxxxxxx > +Description: > + (RO) [For Dynamic Capacity regions only] Users can use the > + extent information to create DAX devices on specific extents. > + This is done by creating and destroying DAX devices in specific > + sequences and looking at the mappings created. Similar to earlier patch, maybe put this doc for the directory, then have much less duplication? > Extent offset > + within the region. > + > +What: /sys/bus/cxl/devices/dax_regionX/extentX.Y/length > +Date: December, 2024 > +KernelVersion: v6.13 > +Contact: linux-cxl@xxxxxxxxxxxxxxx > +Description: > + (RO) [For Dynamic Capacity regions only] Users can use the > + extent information to create DAX devices on specific extents. > + This is done by creating and destroying DAX devices in specific > + sequences and looking at the mappings created. Extent length > + within the region. > + > +What: /sys/bus/cxl/devices/dax_regionX/extentX.Y/tag > +Date: December, 2024 > +KernelVersion: v6.13 > +Contact: linux-cxl@xxxxxxxxxxxxxxx > +Description: > + (RO) [For Dynamic Capacity regions only] Users can use the > + extent information to create DAX devices on specific extents. > + This is done by creating and destroying DAX devices in specific > + sequences and looking at the mappings created. Extent tag. Maybe say we are treating it as a UUID? > diff --git a/drivers/cxl/core/extent.c b/drivers/cxl/core/extent.c > index 69a7614ba6a9..a1eb6e8e4f1a 100644 > --- a/drivers/cxl/core/extent.c > +++ b/drivers/cxl/core/extent.c > @@ -6,6 +6,63 @@ > +static struct attribute *region_extent_attrs[] = { > + &dev_attr_offset.attr, > + &dev_attr_length.attr, > + &dev_attr_tag.attr, > + NULL, No need for trailing comma (one of my 'favourite' review comments :) > +};