On Thu, 14 Jul 2022 17:02:41 -0700
Dan Williams <dan.j.williams@xxxxxxxxx> wrote:
> The region provisioning process involves allocating DPA to a set of
> endpoint decoders, and HPA plus the region geometry to a region device.
> Then the decoder is assigned to the region. At this point several
> validation steps can be performed to validate that the decoder is
> suitable to participate in the region.
>
> Co-developed-by: Ben Widawsky <bwidawsk@xxxxxxxxxx>
> Signed-off-by: Ben Widawsky <bwidawsk@xxxxxxxxxx>
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
I think you've lost some planned changes here as typos from v1 review
still here as is the stale comment.
With those fixed
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index b1e847827c6b..871bfdbb9bc8 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> +/*
> + * - Check that the given endpoint is attached to a host-bridge identified
> + * in the root interleave.
In reply to v1 review I think you said you had dropped this comment as stale?
> + */
> +static int cxl_region_attach(struct cxl_region *cxlr,
> + struct cxl_endpoint_decoder *cxled, int pos)
> +{
> + struct cxl_region_params *p = &cxlr->params;
> +
> + if (cxled->mode == CXL_DECODER_DEAD) {
> + dev_dbg(&cxlr->dev, "%s dead\n", dev_name(&cxled->cxld.dev));
> + return -ENODEV;
> + }
> +
> + if (pos >= p->interleave_ways) {
> + dev_dbg(&cxlr->dev, "position %d out of range %d\n", pos,
> + p->interleave_ways);
> + return -ENXIO;
> + }
> +
> + if (p->targets[pos] == cxled)
> + return 0;
> +
> + if (p->targets[pos]) {
> + struct cxl_endpoint_decoder *cxled_target = p->targets[pos];
> + struct cxl_memdev *cxlmd_target = cxled_to_memdev(cxled_target);
> +
> + dev_dbg(&cxlr->dev, "position %d already assigned to %s:%s\n",
> + pos, dev_name(&cxlmd_target->dev),
> + dev_name(&cxled_target->cxld.dev));
> + return -EBUSY;
> + }
> +
> + p->targets[pos] = cxled;
> + cxled->pos = pos;
> + p->nr_targets++;
> +
> + return 0;
> +}
> +
> +static void cxl_region_detach(struct cxl_endpoint_decoder *cxled)
> +{
> + struct cxl_region *cxlr = cxled->cxld.region;
> + struct cxl_region_params *p;
> +
> + lockdep_assert_held_write(&cxl_region_rwsem);
> +
> + if (!cxlr)
> + return;
> +
> + p = &cxlr->params;
> + get_device(&cxlr->dev);
> +
> + if (cxled->pos < 0 || cxled->pos >= p->interleave_ways ||
> + p->targets[cxled->pos] != cxled) {
> + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
> +
> + dev_WARN_ONCE(&cxlr->dev, 1, "expected %s:%s at position %d\n",
> + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
> + cxled->pos);
> + goto out;
> + }
> +
> + p->targets[cxled->pos] = NULL;
> + p->nr_targets--;
> +
> + /* notify the region driver that one of its targets has deparated */
typo still here.
> + up_write(&cxl_region_rwsem);
> + device_release_driver(&cxlr->dev);
> + down_write(&cxl_region_rwsem);
> +out:
> + put_device(&cxlr->dev);
> +}
