cxl/core/region: move dax region device logic into region_dax.c

core/region.c is overloaded with per-region control logic (pmem, dax,
sysram, etc). Move the CXL DAX region device infrastructure from
region.c into a new region_dax.c file.

This will also allow us to add additional dax-driver integration paths
that don't further dirty the core region.c logic.

No functional changes.

Signed-off-by: Gregory Price <gourry@gourry.net>
Co-developed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Link: https://patch.msgid.link/20260327020203.876122-3-gourry@gourry.net
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index f73776fe323be2e1dc87aab4eca2c0c8d71cdd42..ce7213818d3c09edf2f2aacf626723f46f0e7fb5 100644 (file)
--- a/drivers/cxl/core/Makefile
+++ b/drivers/cxl/core/Makefile
@@ -15,7 +15,7 @@ cxl_core-y += hdm.o
 cxl_core-y += pmu.o
 cxl_core-y += cdat.o
 cxl_core-$(CONFIG_TRACING) += trace.o
-cxl_core-$(CONFIG_CXL_REGION) += region.o region_pmem.o
+cxl_core-$(CONFIG_CXL_REGION) += region.o region_pmem.o region_dax.o
 cxl_core-$(CONFIG_CXL_MCE) += mce.o
 cxl_core-$(CONFIG_CXL_FEATURES) += features.o
 cxl_core-$(CONFIG_CXL_EDAC_MEM_FEATURES) += edac.o

diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 2fa5f2f58c9bd0c272b6591018da56d613fd93f8..5d91e8d0e5bc66f72770539a51390e37ecde66b9 100644 (file)
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -50,6 +50,7 @@ int cxl_get_poison_by_endpoint(struct cxl_port *port);
 struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa);
 u64 cxl_dpa_to_hpa(struct cxl_region *cxlr, const struct cxl_memdev *cxlmd,
                   u64 dpa);
+int devm_cxl_add_dax_region(struct cxl_region *cxlr);
 int devm_cxl_add_pmem_region(struct cxl_region *cxlr);
 
 #else

diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index cf1b7e0617f3254afcc618f8b7f9e33afb23111c..34e2208ff105a3a5b22957e1007bfefd3cd04f3d 100644 (file)
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -3410,105 +3410,6 @@ static int region_offset_to_dpa_result(struct cxl_region *cxlr, u64 offset,
        return -ENXIO;
 }
 
-static void cxl_dax_region_release(struct device *dev)
-{
-       struct cxl_dax_region *cxlr_dax = to_cxl_dax_region(dev);
-
-       kfree(cxlr_dax);
-}
-
-static const struct attribute_group *cxl_dax_region_attribute_groups[] = {
-       &cxl_base_attribute_group,
-       NULL,
-};
-
-const struct device_type cxl_dax_region_type = {
-       .name = "cxl_dax_region",
-       .release = cxl_dax_region_release,
-       .groups = cxl_dax_region_attribute_groups,
-};
-
-static bool is_cxl_dax_region(struct device *dev)
-{
-       return dev->type == &cxl_dax_region_type;
-}
-
-struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
-{
-       if (dev_WARN_ONCE(dev, !is_cxl_dax_region(dev),
-                         "not a cxl_dax_region device\n"))
-               return NULL;
-       return container_of(dev, struct cxl_dax_region, dev);
-}
-EXPORT_SYMBOL_NS_GPL(to_cxl_dax_region, "CXL");
-
-static struct lock_class_key cxl_dax_region_key;
-
-static struct cxl_dax_region *cxl_dax_region_alloc(struct cxl_region *cxlr)
-{
-       struct cxl_region_params *p = &cxlr->params;
-       struct cxl_dax_region *cxlr_dax;
-       struct device *dev;
-
-       guard(rwsem_read)(&cxl_rwsem.region);
-       if (p->state != CXL_CONFIG_COMMIT)
-               return ERR_PTR(-ENXIO);
-
-       cxlr_dax = kzalloc_obj(*cxlr_dax);
-       if (!cxlr_dax)
-               return ERR_PTR(-ENOMEM);
-
-       cxlr_dax->hpa_range.start = p->res->start;
-       cxlr_dax->hpa_range.end = p->res->end;
-
-       dev = &cxlr_dax->dev;
-       cxlr_dax->cxlr = cxlr;
-       device_initialize(dev);
-       lockdep_set_class(&dev->mutex, &cxl_dax_region_key);
-       device_set_pm_not_required(dev);
-       dev->parent = &cxlr->dev;
-       dev->bus = &cxl_bus_type;
-       dev->type = &cxl_dax_region_type;
-
-       return cxlr_dax;
-}
-
-static void cxlr_dax_unregister(void *_cxlr_dax)
-{
-       struct cxl_dax_region *cxlr_dax = _cxlr_dax;
-
-       device_unregister(&cxlr_dax->dev);
-}
-
-static int devm_cxl_add_dax_region(struct cxl_region *cxlr)
-{
-       struct cxl_dax_region *cxlr_dax;
-       struct device *dev;
-       int rc;
-
-       cxlr_dax = cxl_dax_region_alloc(cxlr);
-       if (IS_ERR(cxlr_dax))
-               return PTR_ERR(cxlr_dax);
-
-       dev = &cxlr_dax->dev;
-       rc = dev_set_name(dev, "dax_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_dax_unregister,
-                                       cxlr_dax);
-err:
-       put_device(dev);
-       return rc;
-}
-
 static int match_root_decoder(struct device *dev, const void *data)
 {
        const struct range *r1, *r2 = data;

diff --git a/drivers/cxl/core/region_dax.c b/drivers/cxl/core/region_dax.c
new file mode 100644 (file)
index 0000000..fe36775
--- /dev/null
+++ b/drivers/cxl/core/region_dax.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright(c) 2022 Intel Corporation. All rights reserved.
+ * Copyright(c) 2026 Meta Technologies Inc. All rights reserved.
+ */
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <cxlmem.h>
+#include <cxl.h>
+#include "core.h"
+
+static void cxl_dax_region_release(struct device *dev)
+{
+       struct cxl_dax_region *cxlr_dax = to_cxl_dax_region(dev);
+
+       kfree(cxlr_dax);
+}
+
+static const struct attribute_group *cxl_dax_region_attribute_groups[] = {
+       &cxl_base_attribute_group,
+       NULL
+};
+
+const struct device_type cxl_dax_region_type = {
+       .name = "cxl_dax_region",
+       .release = cxl_dax_region_release,
+       .groups = cxl_dax_region_attribute_groups,
+};
+
+static bool is_cxl_dax_region(struct device *dev)
+{
+       return dev->type == &cxl_dax_region_type;
+}
+
+struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
+{
+       if (dev_WARN_ONCE(dev, !is_cxl_dax_region(dev),
+                         "not a cxl_dax_region device\n"))
+               return NULL;
+       return container_of(dev, struct cxl_dax_region, dev);
+}
+EXPORT_SYMBOL_NS_GPL(to_cxl_dax_region, "CXL");
+
+static struct lock_class_key cxl_dax_region_key;
+
+static struct cxl_dax_region *cxl_dax_region_alloc(struct cxl_region *cxlr)
+{
+       struct cxl_region_params *p = &cxlr->params;
+       struct cxl_dax_region *cxlr_dax;
+       struct device *dev;
+
+       guard(rwsem_read)(&cxl_rwsem.region);
+       if (p->state != CXL_CONFIG_COMMIT)
+               return ERR_PTR(-ENXIO);
+
+       cxlr_dax = kzalloc_obj(*cxlr_dax);
+       if (!cxlr_dax)
+               return ERR_PTR(-ENOMEM);
+
+       cxlr_dax->hpa_range.start = p->res->start;
+       cxlr_dax->hpa_range.end = p->res->end;
+
+       dev = &cxlr_dax->dev;
+       cxlr_dax->cxlr = cxlr;
+       device_initialize(dev);
+       lockdep_set_class(&dev->mutex, &cxl_dax_region_key);
+       device_set_pm_not_required(dev);
+       dev->parent = &cxlr->dev;
+       dev->bus = &cxl_bus_type;
+       dev->type = &cxl_dax_region_type;
+
+       return cxlr_dax;
+}
+
+static void cxlr_dax_unregister(void *_cxlr_dax)
+{
+       struct cxl_dax_region *cxlr_dax = _cxlr_dax;
+
+       device_unregister(&cxlr_dax->dev);
+}
+
+int devm_cxl_add_dax_region(struct cxl_region *cxlr)
+{
+       struct cxl_dax_region *cxlr_dax;
+       struct device *dev;
+       int rc;
+
+       cxlr_dax = cxl_dax_region_alloc(cxlr);
+       if (IS_ERR(cxlr_dax))
+               return PTR_ERR(cxlr_dax);
+
+       dev = &cxlr_dax->dev;
+       rc = dev_set_name(dev, "dax_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_dax_unregister,
+                                       cxlr_dax);
+err:
+       put_device(dev);
+       return rc;
+}

diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild
index f53d79a0566158ad75abc2176e1a8d23be9df6db..d2b291e5f8426189cd78398e4bac5c8a723fe53f 100644 (file)
--- a/tools/testing/cxl/Kbuild
+++ b/tools/testing/cxl/Kbuild
@@ -59,7 +59,7 @@ cxl_core-y += $(CXL_CORE_SRC)/hdm.o
 cxl_core-y += $(CXL_CORE_SRC)/pmu.o
 cxl_core-y += $(CXL_CORE_SRC)/cdat.o
 cxl_core-$(CONFIG_TRACING) += $(CXL_CORE_SRC)/trace.o
-cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o $(CXL_CORE_SRC)/region_pmem.o
+cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o $(CXL_CORE_SRC)/region_pmem.o $(CXL_CORE_SRC)/region_dax.o
 cxl_core-$(CONFIG_CXL_MCE) += $(CXL_CORE_SRC)/mce.o
 cxl_core-$(CONFIG_CXL_FEATURES) += $(CXL_CORE_SRC)/features.o
 cxl_core-$(CONFIG_CXL_EDAC_MEM_FEATURES) += $(CXL_CORE_SRC)/edac.o