The LIBNVDIMM subsystem is a platform agnostic representation of system
NVDIMM / persistent memory resources. To date, the CXL subsystem's
interaction with LIBNVDIMM has been to register an nvdimm-bridge device
and cxl_nvdimm objects to proxy CXL capabilities into existing LIBNVDIMM
subsystem mechanics.
With regions the approach is the same. Create a new cxl_pmem_region
object to proxy CXL region details into a LIBNVDIMM definition. With
this enabling LIBNVDIMM can partition CXL persistent memory regions with
legacy namespace labels. A follow-on patch will add CXL region label and
CXL namespace label support to persist region configurations across
driver reload / system-reset events.
Co-developed-by: Ben Widawsky <bwidawsk@xxxxxxxxxx>
Signed-off-by: Ben Widawsky <bwidawsk@xxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/cxl/core/core.h | 3 +
drivers/cxl/core/pmem.c | 4 -
drivers/cxl/core/port.c | 2
drivers/cxl/core/region.c | 142 +++++++++++++++++++++++++
drivers/cxl/cxl.h | 36 ++++++
drivers/cxl/pmem.c | 238 ++++++++++++++++++++++++++++++++++++++++++
drivers/nvdimm/region_devs.c | 28 ++++-
include/linux/libnvdimm.h | 5 +
8 files changed, 446 insertions(+), 12 deletions(-)
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 391aadf9e7fa..1d8f87be283f 100644
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -13,11 +13,13 @@ extern struct attribute_group cxl_base_attribute_group;
extern struct device_attribute dev_attr_create_pmem_region;
extern struct device_attribute dev_attr_delete_region;
extern struct device_attribute dev_attr_region;
+extern const struct device_type cxl_pmem_region_type;
extern const struct device_type cxl_region_type;
void cxl_decoder_kill_region(struct cxl_endpoint_decoder *cxled);
#define CXL_REGION_ATTR(x) (&dev_attr_##x.attr)
#define CXL_REGION_TYPE(x) (&cxl_region_type)
#define SET_CXL_REGION_ATTR(x) (&dev_attr_##x.attr),
+#define CXL_PMEM_REGION_TYPE(x) (&cxl_pmem_region_type)
int cxl_region_init(void);
void cxl_region_exit(void);
#else
@@ -34,6 +36,7 @@ static inline void cxl_region_exit(void)
#define CXL_REGION_ATTR(x) NULL
#define CXL_REGION_TYPE(x) NULL
#define SET_CXL_REGION_ATTR(x)
+#define CXL_PMEM_REGION_TYPE(x) NULL
#endif
struct cxl_send_command;
diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c
index bec7cfb54ebf..1d12a8206444 100644
--- a/drivers/cxl/core/pmem.c
+++ b/drivers/cxl/core/pmem.c
@@ -62,9 +62,9 @@ static int match_nvdimm_bridge(struct device *dev, void *data)
return is_cxl_nvdimm_bridge(dev);
}
-struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd)
+struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *start)
{
- struct cxl_port *port = find_cxl_root(&cxl_nvd->dev);
+ struct cxl_port *port = find_cxl_root(start);
struct device *dev;
if (!port)
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 194003525397..af65491d878b 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -44,6 +44,8 @@ static int cxl_device_id(struct device *dev)
return CXL_DEVICE_NVDIMM_BRIDGE;
if (dev->type == &cxl_nvdimm_type)
return CXL_DEVICE_NVDIMM;
+ if (dev->type == CXL_PMEM_REGION_TYPE())
+ return CXL_DEVICE_PMEM_REGION;
if (is_cxl_port(dev)) {
if (is_cxl_root(to_cxl_port(dev)))
return CXL_DEVICE_ROOT;
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 20871bdb6858..23d1a34077be 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -1644,6 +1644,139 @@ static ssize_t delete_region_store(struct device *dev,
}
DEVICE_ATTR_WO(delete_region);
+static void cxl_pmem_region_release(struct device *dev)
+{
+ struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
+ int i;
+
+ for (i = 0; i < cxlr_pmem->nr_mappings; i++) {
+ struct cxl_memdev *cxlmd = cxlr_pmem->mapping[i].cxlmd;
+
+ put_device(&cxlmd->dev);
+ }
+
+ kfree(cxlr_pmem);
+}
+
+static const struct attribute_group *cxl_pmem_region_attribute_groups[] = {
+ &cxl_base_attribute_group,
+ NULL,
+};
+
+const struct device_type cxl_pmem_region_type = {
+ .name = "cxl_pmem_region",
+ .release = cxl_pmem_region_release,
+ .groups = cxl_pmem_region_attribute_groups,
+};
+
+bool is_cxl_pmem_region(struct device *dev)
+{
+ return dev->type == &cxl_pmem_region_type;
+}
+EXPORT_SYMBOL_NS_GPL(is_cxl_pmem_region, CXL);
+
+struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
+{
+ if (dev_WARN_ONCE(dev, !is_cxl_pmem_region(dev),
+ "not a cxl_pmem_region device\n"))
+ return NULL;
+ return container_of(dev, struct cxl_pmem_region, dev);
+}
+EXPORT_SYMBOL_NS_GPL(to_cxl_pmem_region, CXL);
+
+static struct lock_class_key cxl_pmem_region_key;
+
+static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr)
+{
+ struct cxl_region_params *p = &cxlr->params;
+ struct cxl_pmem_region *cxlr_pmem;
+ struct device *dev;
+ int i;
+
+ down_read(&cxl_region_rwsem);
+ if (p->state != CXL_CONFIG_COMMIT) {
+ cxlr_pmem = ERR_PTR(-ENXIO);
+ goto out;
+ }
+
+ cxlr_pmem = kzalloc(struct_size(cxlr_pmem, mapping, p->nr_targets),
+ GFP_KERNEL);
+ if (!cxlr_pmem) {
+ cxlr_pmem = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ cxlr_pmem->hpa_range.start = p->res->start;
+ cxlr_pmem->hpa_range.end = p->res->end;
+
+ /* Snapshot the region configuration underneath the cxl_region_rwsem */
+ cxlr_pmem->nr_mappings = p->nr_targets;
+ for (i = 0; i < p->nr_targets; i++) {
+ struct cxl_endpoint_decoder *cxled = p->targets[i];
+ struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
+ struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i];
+
+ m->cxlmd = cxlmd;
+ get_device(&cxlmd->dev);
+ m->start = cxled->dpa_res->start;
+ m->size = resource_size(cxled->dpa_res);
+ m->position = i;
+ }
+
+ dev = &cxlr_pmem->dev;
+ cxlr_pmem->cxlr = cxlr;
+ device_initialize(dev);
+ lockdep_set_class(&dev->mutex, &cxl_pmem_region_key);
+ device_set_pm_not_required(dev);
+ dev->parent = &cxlr->dev;
+ dev->bus = &cxl_bus_type;
+ dev->type = &cxl_pmem_region_type;
+out:
+ up_read(&cxl_region_rwsem);
+
+ return cxlr_pmem;
+}
+
+static void cxlr_pmem_unregister(void *dev)
+{
+ device_unregister(dev);
+}
+
+/**
+ * devm_cxl_add_pmem_region() - add a cxl_region-to-nd_region bridge
+ * @cxlr: parent CXL region for this pmem region bridge device
+ *
+ * Return: 0 on success negative error code on failure.
+ */
+static int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
+{
+ struct cxl_pmem_region *cxlr_pmem;
+ struct device *dev;
+ int rc;
+
+ cxlr_pmem = cxl_pmem_region_alloc(cxlr);
+ if (IS_ERR(cxlr_pmem))
+ return PTR_ERR(cxlr_pmem);
+
+ dev = &cxlr_pmem->dev;
+ rc = dev_set_name(dev, "pmem_region%d", cxlr->id);
+ if (rc)
+ goto err;
+
+ rc = device_add(dev);
+ if (rc)
+ goto err;
+
+ dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent),
+ dev_name(dev));
+
+ return devm_add_action_or_reset(&cxlr->dev, cxlr_pmem_unregister, dev);
+
+err:
+ put_device(dev);
+ return rc;
+}
+
static int cxl_region_probe(struct device *dev)
{
struct cxl_region *cxlr = to_cxl_region(dev);
@@ -1667,7 +1800,14 @@ static int cxl_region_probe(struct device *dev)
*/
up_read(&cxl_region_rwsem);
- return rc;
+ switch (cxlr->mode) {
+ case CXL_DECODER_PMEM:
+ return devm_cxl_add_pmem_region(cxlr);
+ default:
+ dev_dbg(&cxlr->dev, "unsupported region mode: %d\n",
+ cxlr->mode);
+ return -ENXIO;
+ }
}
static struct cxl_driver cxl_region_driver = {
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index a32093602df9..8a484acbb32d 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -419,6 +419,25 @@ struct cxl_nvdimm {
struct device dev;
struct cxl_memdev *cxlmd;
struct cxl_nvdimm_bridge *bridge;
+ struct cxl_pmem_region *region;
+};
+
+struct cxl_pmem_region_mapping {
+ struct cxl_memdev *cxlmd;
+ struct cxl_nvdimm *cxl_nvd;
+ u64 start;
+ u64 size;
+ int position;
+};
+
+struct cxl_pmem_region {
+ struct device dev;
+ struct cxl_region *cxlr;
+ struct nd_region *nd_region;
+ struct cxl_nvdimm_bridge *bridge;
+ struct range hpa_range;
+ int nr_mappings;
+ struct cxl_pmem_region_mapping mapping[];
};
/**
@@ -594,6 +613,7 @@ void cxl_driver_unregister(struct cxl_driver *cxl_drv);
#define CXL_DEVICE_ROOT 4
#define CXL_DEVICE_MEMORY_EXPANDER 5
#define CXL_DEVICE_REGION 6
+#define CXL_DEVICE_PMEM_REGION 7
#define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
#define CXL_MODALIAS_FMT "cxl:t%d"
@@ -605,7 +625,21 @@ struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
bool is_cxl_nvdimm(struct device *dev);
bool is_cxl_nvdimm_bridge(struct device *dev);
int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd);
-struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd);
+struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *dev);
+
+#ifdef CONFIG_CXL_REGION
+bool is_cxl_pmem_region(struct device *dev);
+struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
+#else
+static inline bool is_cxl_pmem_region(struct device *dev)
+{
+ return false;
+}
+static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
+{
+ return NULL;
+}
+#endif
/*
* Unit test builds overrides this to __weak, find the 'strong' version
diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
index b271f6e90b91..e69f99a0747d 100644
--- a/drivers/cxl/pmem.c
+++ b/drivers/cxl/pmem.c
@@ -7,6 +7,7 @@
#include <linux/ndctl.h>
#include <linux/async.h>
#include <linux/slab.h>
+#include <linux/nd.h>
#include "cxlmem.h"
#include "cxl.h"
@@ -27,6 +28,19 @@ static void clear_exclusive(void *cxlds)
static void unregister_nvdimm(void *nvdimm)
{
struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
+ struct cxl_nvdimm_bridge *cxl_nvb = cxl_nvd->bridge;
+ struct cxl_pmem_region *cxlr_pmem;
+
+ device_lock(&cxl_nvb->dev);
+ cxlr_pmem = cxl_nvd->region;
+ dev_set_drvdata(&cxl_nvd->dev, NULL);
+ cxl_nvd->region = NULL;
+ device_unlock(&cxl_nvb->dev);
+
+ if (cxlr_pmem) {
+ device_release_driver(&cxlr_pmem->dev);
+ put_device(&cxlr_pmem->dev);
+ }
nvdimm_delete(nvdimm);
cxl_nvd->bridge = NULL;
@@ -42,7 +56,7 @@ static int cxl_nvdimm_probe(struct device *dev)
struct nvdimm *nvdimm;
int rc;
- cxl_nvb = cxl_find_nvdimm_bridge(cxl_nvd);
+ cxl_nvb = cxl_find_nvdimm_bridge(dev);
if (!cxl_nvb)
return -ENXIO;
@@ -223,6 +237,21 @@ static int cxl_nvdimm_release_driver(struct device *dev, void *cxl_nvb)
return 0;
}
+static int cxl_pmem_region_release_driver(struct device *dev, void *cxl_nvb)
+{
+ struct cxl_pmem_region *cxlr_pmem;
+
+ if (!is_cxl_pmem_region(dev))
+ return 0;
+
+ cxlr_pmem = to_cxl_pmem_region(dev);
+ if (cxlr_pmem->bridge != cxl_nvb)
+ return 0;
+
+ device_release_driver(dev);
+ return 0;
+}
+
static void offline_nvdimm_bus(struct cxl_nvdimm_bridge *cxl_nvb,
struct nvdimm_bus *nvdimm_bus)
{
@@ -234,6 +263,8 @@ static void offline_nvdimm_bus(struct cxl_nvdimm_bridge *cxl_nvb,
* nvdimm_bus_unregister() rips the nvdimm objects out from
* underneath them.
*/
+ bus_for_each_dev(&cxl_bus_type, NULL, cxl_nvb,
+ cxl_pmem_region_release_driver);
bus_for_each_dev(&cxl_bus_type, NULL, cxl_nvb,
cxl_nvdimm_release_driver);
nvdimm_bus_unregister(nvdimm_bus);
@@ -328,6 +359,203 @@ static struct cxl_driver cxl_nvdimm_bridge_driver = {
.id = CXL_DEVICE_NVDIMM_BRIDGE,
};
+static int match_cxl_nvdimm(struct device *dev, void *data)
+{
+ return is_cxl_nvdimm(dev);
+}
+
+static void unregister_nvdimm_region(void *nd_region)
+{
+ struct cxl_nvdimm_bridge *cxl_nvb;
+ struct cxl_pmem_region *cxlr_pmem;
+ int i;
+
+ cxlr_pmem = nd_region_provider_data(nd_region);
+ cxl_nvb = cxlr_pmem->bridge;
+ device_lock(&cxl_nvb->dev);
+ for (i = 0; i < cxlr_pmem->nr_mappings; i++) {
+ struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i];
+ struct cxl_nvdimm *cxl_nvd = m->cxl_nvd;
+
+ if (cxl_nvd->region) {
+ put_device(&cxlr_pmem->dev);
+ cxl_nvd->region = NULL;
+ }
+ }
+ device_unlock(&cxl_nvb->dev);
+
+ nvdimm_region_delete(nd_region);
+}
+
+static void cxlr_pmem_remove_resource(void *res)
+{
+ remove_resource(res);
+}
+
+struct cxl_pmem_region_info {
+ u64 offset;
+ u64 serial;
+};
+
+static int cxl_pmem_region_probe(struct device *dev)
+{
+ struct nd_mapping_desc mappings[CXL_DECODER_MAX_INTERLEAVE];
+ struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
+ struct cxl_region *cxlr = cxlr_pmem->cxlr;
+ struct cxl_pmem_region_info *info = NULL;
+ struct cxl_nvdimm_bridge *cxl_nvb;
+ struct nd_interleave_set *nd_set;
+ struct nd_region_desc ndr_desc;
+ struct cxl_nvdimm *cxl_nvd;
+ struct nvdimm *nvdimm;
+ struct resource *res;
+ int rc, i = 0;
+
+ cxl_nvb = cxl_find_nvdimm_bridge(&cxlr_pmem->mapping[0].cxlmd->dev);
+ if (!cxl_nvb) {
+ dev_dbg(dev, "bridge not found\n");
+ return -ENXIO;
+ }
+ cxlr_pmem->bridge = cxl_nvb;
+
+ device_lock(&cxl_nvb->dev);
+ if (!cxl_nvb->nvdimm_bus) {
+ dev_dbg(dev, "nvdimm bus not found\n");
+ rc = -ENXIO;
+ goto err;
+ }
+
+ memset(&mappings, 0, sizeof(mappings));
+ memset(&ndr_desc, 0, sizeof(ndr_desc));
+
+ res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL);
+ if (!res) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ res->name = "Persistent Memory";
+ res->start = cxlr_pmem->hpa_range.start;
+ res->end = cxlr_pmem->hpa_range.end;
+ res->flags = IORESOURCE_MEM;
+ res->desc = IORES_DESC_PERSISTENT_MEMORY;
+
+ rc = insert_resource(&iomem_resource, res);
+ if (rc)
+ goto err;
+
+ rc = devm_add_action_or_reset(dev, cxlr_pmem_remove_resource, res);
+ if (rc)
+ goto err;
+
+ ndr_desc.res = res;
+ ndr_desc.provider_data = cxlr_pmem;
+
+ ndr_desc.numa_node = memory_add_physaddr_to_nid(res->start);
+ ndr_desc.target_node = phys_to_target_node(res->start);
+ if (ndr_desc.target_node == NUMA_NO_NODE) {
+ ndr_desc.target_node = ndr_desc.numa_node;
+ dev_dbg(&cxlr->dev, "changing target node from %d to %d",
+ NUMA_NO_NODE, ndr_desc.target_node);
+ }
+
+ nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL);
+ if (!nd_set) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ ndr_desc.memregion = cxlr->id;
+ set_bit(ND_REGION_CXL, &ndr_desc.flags);
+ set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
+
+ info = kmalloc_array(cxlr_pmem->nr_mappings, sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ for (i = 0; i < cxlr_pmem->nr_mappings; i++) {
+ struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i];
+ struct cxl_memdev *cxlmd = m->cxlmd;
+ struct cxl_dev_state *cxlds = cxlmd->cxlds;
+ struct device *d;
+
+ d = device_find_child(&cxlmd->dev, NULL, match_cxl_nvdimm);
+ if (!d) {
+ dev_dbg(dev, "[%d]: %s: no cxl_nvdimm found\n", i,
+ dev_name(&cxlmd->dev));
+ rc = -ENODEV;
+ goto err;
+ }
+
+ /* safe to drop ref now with bridge lock held */
+ put_device(d);
+
+ cxl_nvd = to_cxl_nvdimm(d);
+ nvdimm = dev_get_drvdata(&cxl_nvd->dev);
+ if (!nvdimm) {
+ dev_dbg(dev, "[%d]: %s: no nvdimm found\n", i,
+ dev_name(&cxlmd->dev));
+ rc = -ENODEV;
+ goto err;
+ }
+ cxl_nvd->region = cxlr_pmem;
+ get_device(&cxlr_pmem->dev);
+ m->cxl_nvd = cxl_nvd;
+ mappings[i] = (struct nd_mapping_desc) {
+ .nvdimm = nvdimm,
+ .start = m->start,
+ .size = m->size,
+ .position = i,
+ };
+ info[i].offset = m->start;
+ info[i].serial = cxlds->serial;
+ }
+ ndr_desc.num_mappings = cxlr_pmem->nr_mappings;
+ ndr_desc.mapping = mappings;
+
+ /*
+ * TODO enable CXL labels which skip the need for 'interleave-set cookie'
+ */
+ nd_set->cookie1 =
+ nd_fletcher64(info, sizeof(*info) * cxlr_pmem->nr_mappings, 0);
+ nd_set->cookie2 = nd_set->cookie1;
+ ndr_desc.nd_set = nd_set;
+
+ cxlr_pmem->nd_region =
+ nvdimm_pmem_region_create(cxl_nvb->nvdimm_bus, &ndr_desc);
+ if (IS_ERR(cxlr_pmem->nd_region)) {
+ rc = PTR_ERR(cxlr_pmem->nd_region);
+ goto err;
+ }
+
+ rc = devm_add_action_or_reset(dev, unregister_nvdimm_region,
+ cxlr_pmem->nd_region);
+out:
+ kfree(info);
+ device_unlock(&cxl_nvb->dev);
+ put_device(&cxl_nvb->dev);
+
+ return rc;
+
+err:
+ dev_dbg(dev, "failed to create nvdimm region\n");
+ for (i--; i >= 0; i--) {
+ nvdimm = mappings[i].nvdimm;
+ cxl_nvd = nvdimm_provider_data(nvdimm);
+ put_device(&cxl_nvd->region->dev);
+ cxl_nvd->region = NULL;
+ }
+ goto out;
+}
+
+static struct cxl_driver cxl_pmem_region_driver = {
+ .name = "cxl_pmem_region",
+ .probe = cxl_pmem_region_probe,
+ .id = CXL_DEVICE_PMEM_REGION,
+};
+
/*
* Return all bridges to the CXL_NVB_NEW state to invalidate any
* ->state_work referring to the now destroyed cxl_pmem_wq.
@@ -372,8 +600,14 @@ static __init int cxl_pmem_init(void)
if (rc)
goto err_nvdimm;
+ rc = cxl_driver_register(&cxl_pmem_region_driver);
+ if (rc)
+ goto err_region;
+
return 0;
+err_region:
+ cxl_driver_unregister(&cxl_nvdimm_driver);
err_nvdimm:
cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
err_bridge:
@@ -383,6 +617,7 @@ static __init int cxl_pmem_init(void)
static __exit void cxl_pmem_exit(void)
{
+ cxl_driver_unregister(&cxl_pmem_region_driver);
cxl_driver_unregister(&cxl_nvdimm_driver);
cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
destroy_cxl_pmem_wq();
@@ -394,3 +629,4 @@ module_exit(cxl_pmem_exit);
MODULE_IMPORT_NS(CXL);
MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM_BRIDGE);
MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM);
+MODULE_ALIAS_CXL(CXL_DEVICE_PMEM_REGION);
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;
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 0d61e07b6827..c74acfa1a3fe 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -59,6 +59,9 @@ enum {
/* Platform provides asynchronous flush mechanism */
ND_REGION_ASYNC = 3,
+ /* Region was created by CXL subsystem */
+ ND_REGION_CXL = 4,
+
/* mark newly adjusted resources as requiring a label update */
DPA_RESOURCE_ADJUSTED = 1 << 0,
};
@@ -122,6 +125,7 @@ struct nd_region_desc {
int numa_node;
int target_node;
unsigned long flags;
+ int memregion;
struct device_node *of_node;
int (*flush)(struct nd_region *nd_region, struct bio *bio);
};
@@ -259,6 +263,7 @@ static inline struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus,
cmd_mask, num_flush, flush_wpq, NULL, NULL, NULL);
}
void nvdimm_delete(struct nvdimm *nvdimm);
+void nvdimm_region_delete(struct nd_region *nd_region);
const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd);
const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd);
