return rc;
}
-/*
- * - Check that the given endpoint is attached to a host-bridge identified
- * in the root interleave.
+static int match_free_decoder(struct device *dev, void *data)
+{
+ struct cxl_decoder *cxld;
+ int *id = data;
+
+ if (!is_switch_decoder(dev))
+ return 0;
+
+ cxld = to_cxl_decoder(dev);
+
+ /* enforce ordered allocation */
+ if (cxld->id != *id)
+ return 0;
+
+ if (!cxld->region)
+ return 1;
+
+ (*id)++;
+
+ return 0;
+}
+
+static struct cxl_decoder *cxl_region_find_decoder(struct cxl_port *port,
+ struct cxl_region *cxlr)
+{
+ struct device *dev;
+ int id = 0;
+
+ dev = device_find_child(&port->dev, &id, match_free_decoder);
+ if (!dev)
+ return NULL;
+ /*
+ * This decoder is pinned registered as long as the endpoint decoder is
+ * registered, and endpoint decoder unregistration holds the
+ * cxl_region_rwsem over unregister events, so no need to hold on to
+ * this extra reference.
+ */
+ put_device(dev);
+ return to_cxl_decoder(dev);
+}
+
+static struct cxl_region_ref *alloc_region_ref(struct cxl_port *port,
+ struct cxl_region *cxlr)
+{
+ struct cxl_region_ref *cxl_rr;
+ int rc;
+
+ cxl_rr = kzalloc(sizeof(*cxl_rr), GFP_KERNEL);
+ if (!cxl_rr)
+ return NULL;
+ cxl_rr->port = port;
+ cxl_rr->region = cxlr;
+ xa_init(&cxl_rr->endpoints);
+
+ rc = xa_insert(&port->regions, (unsigned long)cxlr, cxl_rr, GFP_KERNEL);
+ if (rc) {
+ dev_dbg(&cxlr->dev,
+ "%s: failed to track region reference: %d\n",
+ dev_name(&port->dev), rc);
+ kfree(cxl_rr);
+ return NULL;
+ }
+
+ return cxl_rr;
+}
+
+static void free_region_ref(struct cxl_region_ref *cxl_rr)
+{
+ struct cxl_port *port = cxl_rr->port;
+ struct cxl_region *cxlr = cxl_rr->region;
+ struct cxl_decoder *cxld = cxl_rr->decoder;
+
+ dev_WARN_ONCE(&cxlr->dev, cxld->region != cxlr, "region mismatch\n");
+ if (cxld->region == cxlr) {
+ cxld->region = NULL;
+ put_device(&cxlr->dev);
+ }
+
+ xa_erase(&port->regions, (unsigned long)cxlr);
+ xa_destroy(&cxl_rr->endpoints);
+ kfree(cxl_rr);
+}
+
+static int cxl_rr_ep_add(struct cxl_region_ref *cxl_rr,
+ struct cxl_endpoint_decoder *cxled)
+{
+ int rc;
+ struct cxl_port *port = cxl_rr->port;
+ struct cxl_region *cxlr = cxl_rr->region;
+ struct cxl_decoder *cxld = cxl_rr->decoder;
+ struct cxl_ep *ep = cxl_ep_load(port, cxled_to_memdev(cxled));
+
+ rc = xa_insert(&cxl_rr->endpoints, (unsigned long)cxled, ep,
+ GFP_KERNEL);
+ if (rc)
+ return rc;
+ cxl_rr->nr_eps++;
+
+ if (!cxld->region) {
+ cxld->region = cxlr;
+ get_device(&cxlr->dev);
+ }
+
+ return 0;
+}
+
+/**
+ * cxl_port_attach_region() - track a region's interest in a port by endpoint
+ * @port: port to add a new region reference 'struct cxl_region_ref'
+ * @cxlr: region to attach to @port
+ * @cxled: endpoint decoder used to create or further pin a region reference
+ * @pos: interleave position of @cxled in @cxlr
+ *
+ * The attach event is an opportunity to validate CXL decode setup
+ * constraints and record metadata needed for programming HDM decoders,
+ * in particular decoder target lists.
+ *
+ * The steps are:
+ * - validate that there are no other regions with a higher HPA already
+ * associated with @port
+ * - establish a region reference if one is not already present
+ * - additionally allocate a decoder instance that will host @cxlr on
+ * @port
+ * - pin the region reference by the endpoint
+ * - account for how many entries in @port's target list are needed to
+ * cover all of the added endpoints.
*/
+static int cxl_port_attach_region(struct cxl_port *port,
+ struct cxl_region *cxlr,
+ struct cxl_endpoint_decoder *cxled, int pos)
+{
+ struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
+ struct cxl_ep *ep = cxl_ep_load(port, cxlmd);
+ struct cxl_region_ref *cxl_rr = NULL, *iter;
+ struct cxl_region_params *p = &cxlr->params;
+ struct cxl_decoder *cxld = NULL;
+ unsigned long index;
+ int rc = -EBUSY;
+
+ lockdep_assert_held_write(&cxl_region_rwsem);
+
+ xa_for_each(&port->regions, index, iter) {
+ struct cxl_region_params *ip = &iter->region->params;
+
+ if (iter->region == cxlr)
+ cxl_rr = iter;
+ if (ip->res->start > p->res->start) {
+ dev_dbg(&cxlr->dev,
+ "%s: HPA order violation %s:%pr vs %pr\n",
+ dev_name(&port->dev),
+ dev_name(&iter->region->dev), ip->res, p->res);
+ return -EBUSY;
+ }
+ }
+
+ if (cxl_rr) {
+ struct cxl_ep *ep_iter;
+ int found = 0;
+
+ cxld = cxl_rr->decoder;
+ xa_for_each(&cxl_rr->endpoints, index, ep_iter) {
+ if (ep_iter == ep)
+ continue;
+ if (ep_iter->next == ep->next) {
+ found++;
+ break;
+ }
+ }
+
+ /*
+ * If this is a new target or if this port is direct connected
+ * to this endpoint then add to the target count.
+ */
+ if (!found || !ep->next)
+ cxl_rr->nr_targets++;
+ } else {
+ cxl_rr = alloc_region_ref(port, cxlr);
+ if (!cxl_rr) {
+ dev_dbg(&cxlr->dev,
+ "%s: failed to allocate region reference\n",
+ dev_name(&port->dev));
+ return -ENOMEM;
+ }
+ }
+
+ if (!cxld) {
+ if (port == cxled_to_port(cxled))
+ cxld = &cxled->cxld;
+ else
+ cxld = cxl_region_find_decoder(port, cxlr);
+ if (!cxld) {
+ dev_dbg(&cxlr->dev, "%s: no decoder available\n",
+ dev_name(&port->dev));
+ goto out_erase;
+ }
+
+ if (cxld->region) {
+ dev_dbg(&cxlr->dev, "%s: %s already attached to %s\n",
+ dev_name(&port->dev), dev_name(&cxld->dev),
+ dev_name(&cxld->region->dev));
+ rc = -EBUSY;
+ goto out_erase;
+ }
+
+ cxl_rr->decoder = cxld;
+ }
+
+ rc = cxl_rr_ep_add(cxl_rr, cxled);
+ if (rc) {
+ dev_dbg(&cxlr->dev,
+ "%s: failed to track endpoint %s:%s reference\n",
+ dev_name(&port->dev), dev_name(&cxlmd->dev),
+ dev_name(&cxld->dev));
+ goto out_erase;
+ }
+
+ return 0;
+out_erase:
+ if (cxl_rr->nr_eps == 0)
+ free_region_ref(cxl_rr);
+ return rc;
+}
+
+static struct cxl_region_ref *cxl_rr_load(struct cxl_port *port,
+ struct cxl_region *cxlr)
+{
+ return xa_load(&port->regions, (unsigned long)cxlr);
+}
+
+static void cxl_port_detach_region(struct cxl_port *port,
+ struct cxl_region *cxlr,
+ struct cxl_endpoint_decoder *cxled)
+{
+ struct cxl_region_ref *cxl_rr;
+ struct cxl_ep *ep;
+
+ lockdep_assert_held_write(&cxl_region_rwsem);
+
+ cxl_rr = cxl_rr_load(port, cxlr);
+ if (!cxl_rr)
+ return;
+
+ ep = xa_erase(&cxl_rr->endpoints, (unsigned long)cxled);
+ if (ep) {
+ struct cxl_ep *ep_iter;
+ unsigned long index;
+ int found = 0;
+
+ cxl_rr->nr_eps--;
+ xa_for_each(&cxl_rr->endpoints, index, ep_iter) {
+ if (ep_iter->next == ep->next) {
+ found++;
+ break;
+ }
+ }
+ if (!found)
+ cxl_rr->nr_targets--;
+ }
+
+ if (cxl_rr->nr_eps == 0)
+ free_region_ref(cxl_rr);
+}
+
static int cxl_region_attach(struct cxl_region *cxlr,
struct cxl_endpoint_decoder *cxled, int pos)
{
+ struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent);
+ struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
+ struct cxl_port *ep_port, *root_port, *iter;
struct cxl_region_params *p = &cxlr->params;
+ struct cxl_dport *dport;
+ int i, rc = -ENXIO;
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) {
+ /* all full of members, or interleave config not established? */
+ if (p->state > CXL_CONFIG_INTERLEAVE_ACTIVE) {
+ dev_dbg(&cxlr->dev, "region already active\n");
+ return -EBUSY;
+ } else if (p->state < CXL_CONFIG_INTERLEAVE_ACTIVE) {
+ dev_dbg(&cxlr->dev, "interleave config missing\n");
+ return -ENXIO;
+ }
+
+ if (pos < 0 || pos >= p->interleave_ways) {
dev_dbg(&cxlr->dev, "position %d out of range %d\n", pos,
p->interleave_ways);
return -ENXIO;
return -EBUSY;
}
+ for (i = 0; i < p->interleave_ways; i++) {
+ struct cxl_endpoint_decoder *cxled_target;
+ struct cxl_memdev *cxlmd_target;
+
+ cxled_target = p->targets[pos];
+ if (!cxled_target)
+ continue;
+
+ cxlmd_target = cxled_to_memdev(cxled_target);
+ if (cxlmd_target == cxlmd) {
+ dev_dbg(&cxlr->dev,
+ "%s already specified at position %d via: %s\n",
+ dev_name(&cxlmd->dev), pos,
+ dev_name(&cxled_target->cxld.dev));
+ return -EBUSY;
+ }
+ }
+
+ ep_port = cxled_to_port(cxled);
+ root_port = cxlrd_to_port(cxlrd);
+ dport = cxl_find_dport_by_dev(root_port, ep_port->host_bridge);
+ if (!dport) {
+ dev_dbg(&cxlr->dev, "%s:%s invalid target for %s\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
+ dev_name(cxlr->dev.parent));
+ return -ENXIO;
+ }
+
+ if (cxlrd->calc_hb(cxlrd, pos) != dport) {
+ dev_dbg(&cxlr->dev, "%s:%s invalid target position for %s\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
+ dev_name(&cxlrd->cxlsd.cxld.dev));
+ return -ENXIO;
+ }
+
+ if (cxled->cxld.target_type != cxlr->type) {
+ dev_dbg(&cxlr->dev, "%s:%s type mismatch: %d vs %d\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
+ cxled->cxld.target_type, cxlr->type);
+ return -ENXIO;
+ }
+
+ if (!cxled->dpa_res) {
+ dev_dbg(&cxlr->dev, "%s:%s: missing DPA allocation.\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev));
+ return -ENXIO;
+ }
+
+ if (resource_size(cxled->dpa_res) * p->interleave_ways !=
+ resource_size(p->res)) {
+ dev_dbg(&cxlr->dev,
+ "%s:%s: decoder-size-%#llx * ways-%d != region-size-%#llx\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
+ (u64)resource_size(cxled->dpa_res), p->interleave_ways,
+ (u64)resource_size(p->res));
+ return -EINVAL;
+ }
+
+ for (iter = ep_port; !is_cxl_root(iter);
+ iter = to_cxl_port(iter->dev.parent)) {
+ rc = cxl_port_attach_region(iter, cxlr, cxled, pos);
+ if (rc)
+ goto err;
+ }
+
p->targets[pos] = cxled;
cxled->pos = pos;
p->nr_targets++;
+ if (p->nr_targets == p->interleave_ways)
+ p->state = CXL_CONFIG_ACTIVE;
+
return 0;
+
+err:
+ for (iter = ep_port; !is_cxl_root(iter);
+ iter = to_cxl_port(iter->dev.parent))
+ cxl_port_detach_region(iter, cxlr, cxled);
+ return rc;
}
static void cxl_region_detach(struct cxl_endpoint_decoder *cxled)
{
+ struct cxl_port *iter, *ep_port = cxled_to_port(cxled);
struct cxl_region *cxlr = cxled->cxld.region;
struct cxl_region_params *p;
p = &cxlr->params;
get_device(&cxlr->dev);
+ for (iter = ep_port; !is_cxl_root(iter);
+ iter = to_cxl_port(iter->dev.parent))
+ cxl_port_detach_region(iter, cxlr, cxled);
+
if (cxled->pos < 0 || cxled->pos >= p->interleave_ways ||
p->targets[cxled->pos] != cxled) {
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
goto out;
}
+ if (p->state == CXL_CONFIG_ACTIVE)
+ p->state = CXL_CONFIG_INTERLEAVE_ACTIVE;
p->targets[cxled->pos] = NULL;
p->nr_targets--;
- /* notify the region driver that one of its targets has deparated */
+ /* notify the region driver that one of its targets has departed */
up_write(&cxl_region_rwsem);
device_release_driver(&cxlr->dev);
down_write(&cxl_region_rwsem);
projects / ceph-client.git / commitdiff