Jonathan Cameron wrote:
> On Thu, 23 Jun 2022 21:19:42 -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>
> > ---
> > Documentation/ABI/testing/sysfs-bus-cxl | 19 ++
> > drivers/cxl/core/core.h | 6 +
> > drivers/cxl/core/hdm.c | 13 +-
> > drivers/cxl/core/port.c | 12 +-
> > drivers/cxl/core/region.c | 286 +++++++++++++++++++++++-
> > drivers/cxl/cxl.h | 11 +
> > 6 files changed, 342 insertions(+), 5 deletions(-)
> >
>
> A few fixes seems to have ended up in wrong patch.
> Other trivial typos etc inline plus what looks to be an
> item left from a todo list...
>
> ...
>
>
> > diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> > index a604c24ff918..4830365f3857 100644
> > --- a/drivers/cxl/core/region.c
> > +++ b/drivers/cxl/core/region.c
> > @@ -24,6 +24,7 @@
> > * but is only visible for persistent regions.
> > * 1. Interleave granularity
> > * 2. Interleave size
> > + * 3. Decoder targets
> > */
> >
> > /*
> > @@ -138,6 +139,8 @@ static ssize_t interleave_ways_show(struct device *dev,
> > return rc;
> > }
> >
> > +static const struct attribute_group *get_cxl_region_target_group(void);
> > +
> > static ssize_t interleave_ways_store(struct device *dev,
> > struct device_attribute *attr,
> > const char *buf, size_t len)
> > @@ -146,7 +149,7 @@ static ssize_t interleave_ways_store(struct device *dev,
> > struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld;
> > struct cxl_region *cxlr = to_cxl_region(dev);
> > struct cxl_region_params *p = &cxlr->params;
> > - int rc, val;
> > + int rc, val, save;
> > u8 iw;
> >
> > rc = kstrtoint(buf, 0, &val);
> > @@ -175,9 +178,13 @@ static ssize_t interleave_ways_store(struct device *dev,
> > goto out;
> > }
> >
> > + save = p->interleave_ways;
> > p->interleave_ways = val;
> > + rc = sysfs_update_group(&cxlr->dev.kobj, get_cxl_region_target_group());
> > + if (rc)
> > + p->interleave_ways = save;
> > out:
> > - up_read(&cxl_region_rwsem);
> > + up_write(&cxl_region_rwsem);
>
> Bug in earlier patch?
yes, fix now folded earlier. Good spot.
>
> > if (rc)
> > return rc;
> > return len;
> > @@ -234,7 +241,7 @@ static ssize_t interleave_granularity_store(struct device *dev,
> >
> > p->interleave_granularity = val;
> > out:
> > - up_read(&cxl_region_rwsem);
> > + up_write(&cxl_region_rwsem);
>
> Bug in earlier patch?
yup.
>
> > if (rc)
> > return rc;
> > return len;
> > @@ -393,9 +400,262 @@ static const struct attribute_group cxl_region_group = {
> > .is_visible = cxl_region_visible,
> > };
>
> ...
>
> > +/*
> > + * - Check that the given endpoint is attached to a host-bridge identified
> > + * in the root interleave.
>
> Comment on something to fix? Or stale comment that can be dropped?
Stale comment, now dropped.
>
> > + */
> > +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 */
>
> departed?
Yup, thanks.
