1 files changed, 25 insertions, 13 deletions

diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index d976260eca7a..e0875d369762 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);
 }
 
@@ -508,16 +509,13 @@ static ssize_t align_store(struct device *dev,
 {
 	struct nd_region *nd_region = to_nd_region(dev);
 	unsigned long val, dpa;
-	u32 remainder;
+	u32 mappings, remainder;
 	int rc;
 
 	rc = kstrtoul(buf, 0, &val);
 	if (rc)
 		return rc;
 
-	if (!nd_region->ndr_mappings)
-		return -ENXIO;
-
 	/*
 	 * Ensure space-align is evenly divisible by the region
 	 * interleave-width because the kernel typically has no facility
@@ -525,7 +523,8 @@ static ssize_t align_store(struct device *dev,
 	 * contribute to the tail capacity in system-physical-address
 	 * space for the namespace.
 	 */
-	dpa = div_u64_rem(val, nd_region->ndr_mappings, &remainder);
+	mappings = max_t(u32, 1, nd_region->ndr_mappings);
+	dpa = div_u64_rem(val, mappings, &remainder);
 	if (!is_power_of_2(dpa) || dpa < PAGE_SIZE
 			|| val > region_size(nd_region) || remainder)
 		return -EINVAL;
@@ -982,9 +981,14 @@ 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 +1047,10 @@ 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 +1073,13 @@ 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;
@@ -1082,7 +1094,7 @@ int nvdimm_flush(struct nd_region *nd_region, struct bio *bio)
 	return rc;
 }
 /**
- * nvdimm_flush - flush any posted write queues between the cpu and pmem media
+ * generic_nvdimm_flush() - flush any posted write queues between the cpu and pmem media
  * @nd_region: interleaved pmem region
  */
 int generic_nvdimm_flush(struct nd_region *nd_region)