Merge tag 'cxl-for-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull cxl updates from Dan Williams:
 "Compute Express Link (CXL) updates for 6.0:

   - Introduce a 'struct cxl_region' object with support for
     provisioning and assembling persistent memory regions.

   - Introduce alloc_free_mem_region() to accompany the existing
     request_free_mem_region() as a method to allocate physical memory
     capacity out of an existing resource.

   - Export insert_resource_expand_to_fit() for the CXL subsystem to
     late-publish CXL platform windows in iomem_resource.

   - Add a polled mode PCI DOE (Data Object Exchange) driver service and
     use it in cxl_pci to retrieve the CDAT (Coherent Device Attribute
     Table)"

* tag 'cxl-for-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (74 commits)
  cxl/hdm: Fix skip allocations vs multiple pmem allocations
  cxl/region: Disallow region granularity != window granularity
  cxl/region: Fix x1 interleave to greater than x1 interleave routing
  cxl/region: Move HPA setup to cxl_region_attach()
  cxl/region: Fix decoder interleave programming
  Documentation: cxl: remove dangling kernel-doc reference
  cxl/region: describe targets and nr_targets members of cxl_region_params
  cxl/regions: add padding for cxl_rr_ep_add nested lists
  cxl/region: Fix IS_ERR() vs NULL check
  cxl/region: Fix region reference target accounting
  cxl/region: Fix region commit uninitialized variable warning
  cxl/region: Fix port setup uninitialized variable warnings
  cxl/region: Stop initializing interleave granularity
  cxl/hdm: Fix DPA reservation vs cxl_endpoint_decoder lifetime
  cxl/acpi: Minimize granularity for x1 interleaves
  cxl/region: Delete 'region' attribute from root decoders
  cxl/acpi: Autoload driver for 'cxl_acpi' test devices
  cxl/region: decrement ->nr_targets on error in cxl_region_attach()
  cxl/region: prevent underflow in ways_to_cxl()
  cxl/region: uninitialized variable in alloc_hpa()
  ...

1 files changed, 21 insertions, 7 deletions

diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index d976260eca7a..473a71bbd9c9 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -133,7 +133,8 @@ static void nd_region_release(struct device *dev)
 		put_device(&nvdimm->dev);
 	}
 	free_percpu(nd_region->lane);
-	memregion_free(nd_region->id);
+	if (!test_bit(ND_REGION_CXL, &nd_region->flags))
+		memregion_free(nd_region->id);
 	kfree(nd_region);
 }
 
@@ -982,9 +983,14 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 
 	if (!nd_region)
 		return NULL;
-	nd_region->id = memregion_alloc(GFP_KERNEL);
-	if (nd_region->id < 0)
-		goto err_id;
+	/* CXL pre-assigns memregion ids before creating nvdimm regions */
+	if (test_bit(ND_REGION_CXL, &ndr_desc->flags)) {
+		nd_region->id = ndr_desc->memregion;
+	} else {
+		nd_region->id = memregion_alloc(GFP_KERNEL);
+		if (nd_region->id < 0)
+			goto err_id;
+	}
 
 	nd_region->lane = alloc_percpu(struct nd_percpu_lane);
 	if (!nd_region->lane)
@@ -1043,9 +1049,10 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 
 	return nd_region;
 
- err_percpu:
-	memregion_free(nd_region->id);
- err_id:
+err_percpu:
+	if (!test_bit(ND_REGION_CXL, &ndr_desc->flags))
+		memregion_free(nd_region->id);
+err_id:
 	kfree(nd_region);
 	return NULL;
 }
@@ -1068,6 +1075,13 @@ struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
 }
 EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create);
 
+void nvdimm_region_delete(struct nd_region *nd_region)
+{
+	if (nd_region)
+		nd_device_unregister(&nd_region->dev, ND_SYNC);
+}
+EXPORT_SYMBOL_GPL(nvdimm_region_delete);
+
 int nvdimm_flush(struct nd_region *nd_region, struct bio *bio)
 {
 	int rc = 0;