* [PATCH v5 1/3] cxl/core/region: move pmem region driver logic into region_pmem.c
2026-03-27 2:02 [PATCH v5 0/3] pull region-specific logic into new files Gregory Price
@ 2026-03-27 2:02 ` Gregory Price
2026-03-27 16:56 ` Ira Weiny
2026-03-27 2:02 ` [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c Gregory Price
` (2 subsequent siblings)
3 siblings, 1 reply; 12+ messages in thread
From: Gregory Price @ 2026-03-27 2:02 UTC (permalink / raw)
To: linux-cxl
Cc: linux-kernel, kernel-team, dave, jonathan.cameron, dave.jiang,
alison.schofield, vishal.l.verma, ira.weiny, dan.j.williams
core/region.c is overloaded with per-region control logic (pmem, dax,
sysram, etc). Move the pmem region driver logic from region.c into
region_pmem.c make it clear that this code only applies to pmem regions.
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>
---
drivers/cxl/core/Makefile | 2 +-
drivers/cxl/core/core.h | 1 +
drivers/cxl/core/region.c | 184 -------------------------------
drivers/cxl/core/region_pmem.c | 191 +++++++++++++++++++++++++++++++++
tools/testing/cxl/Kbuild | 2 +-
5 files changed, 194 insertions(+), 186 deletions(-)
create mode 100644 drivers/cxl/core/region_pmem.c
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index a639a9499972..f73776fe323b 100644
--- 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
+cxl_core-$(CONFIG_CXL_REGION) += region.o region_pmem.o
cxl_core-$(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 5539e941782f..ef03966eeabd 100644
--- 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_pmem_region(struct cxl_region *cxlr);
#else
static inline u64 cxl_dpa_to_hpa(struct cxl_region *cxlr,
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index f24b7e754727..72aee1408efb 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -2781,46 +2781,6 @@ 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");
-
struct cxl_poison_context {
struct cxl_port *port;
int part;
@@ -3476,64 +3436,6 @@ static int region_offset_to_dpa_result(struct cxl_region *cxlr, u64 offset,
return -ENXIO;
}
-static struct lock_class_key cxl_pmem_region_key;
-
-static int cxl_pmem_region_alloc(struct cxl_region *cxlr)
-{
- struct cxl_region_params *p = &cxlr->params;
- struct cxl_nvdimm_bridge *cxl_nvb;
- struct device *dev;
- int i;
-
- guard(rwsem_read)(&cxl_rwsem.region);
- if (p->state != CXL_CONFIG_COMMIT)
- return -ENXIO;
-
- struct cxl_pmem_region *cxlr_pmem __free(kfree) =
- kzalloc_flex(*cxlr_pmem, mapping, p->nr_targets);
- if (!cxlr_pmem)
- return -ENOMEM;
-
- cxlr_pmem->hpa_range.start = p->res->start;
- cxlr_pmem->hpa_range.end = p->res->end;
-
- /* Snapshot the region configuration underneath the cxl_rwsem.region */
- 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];
-
- /*
- * Regions never span CXL root devices, so by definition the
- * bridge for one device is the same for all.
- */
- if (i == 0) {
- cxl_nvb = cxl_find_nvdimm_bridge(cxlmd->endpoint);
- if (!cxl_nvb)
- return -ENODEV;
- cxlr->cxl_nvb = cxl_nvb;
- }
- 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;
- 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;
- cxlr_pmem->cxlr = cxlr;
- cxlr->cxlr_pmem = no_free_ptr(cxlr_pmem);
-
- return 0;
-}
-
static void cxl_dax_region_release(struct device *dev)
{
struct cxl_dax_region *cxlr_dax = to_cxl_dax_region(dev);
@@ -3597,92 +3499,6 @@ static struct cxl_dax_region *cxl_dax_region_alloc(struct cxl_region *cxlr)
return cxlr_dax;
}
-static void cxlr_pmem_unregister(void *_cxlr_pmem)
-{
- struct cxl_pmem_region *cxlr_pmem = _cxlr_pmem;
- struct cxl_region *cxlr = cxlr_pmem->cxlr;
- struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
-
- /*
- * Either the bridge is in ->remove() context under the device_lock(),
- * or cxlr_release_nvdimm() is cancelling the bridge's release action
- * for @cxlr_pmem and doing it itself (while manually holding the bridge
- * lock).
- */
- device_lock_assert(&cxl_nvb->dev);
- cxlr->cxlr_pmem = NULL;
- cxlr_pmem->cxlr = NULL;
- device_unregister(&cxlr_pmem->dev);
-}
-
-static void cxlr_release_nvdimm(void *_cxlr)
-{
- struct cxl_region *cxlr = _cxlr;
- struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
-
- scoped_guard(device, &cxl_nvb->dev) {
- if (cxlr->cxlr_pmem)
- devm_release_action(&cxl_nvb->dev, cxlr_pmem_unregister,
- cxlr->cxlr_pmem);
- }
- cxlr->cxl_nvb = NULL;
- put_device(&cxl_nvb->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 cxl_nvdimm_bridge *cxl_nvb;
- struct device *dev;
- int rc;
-
- rc = cxl_pmem_region_alloc(cxlr);
- if (rc)
- return rc;
- cxlr_pmem = cxlr->cxlr_pmem;
- cxl_nvb = cxlr->cxl_nvb;
-
- 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));
-
- scoped_guard(device, &cxl_nvb->dev) {
- if (cxl_nvb->dev.driver)
- rc = devm_add_action_or_reset(&cxl_nvb->dev,
- cxlr_pmem_unregister,
- cxlr_pmem);
- else
- rc = -ENXIO;
- }
-
- if (rc)
- goto err_bridge;
-
- /* @cxlr carries a reference on @cxl_nvb until cxlr_release_nvdimm */
- return devm_add_action_or_reset(&cxlr->dev, cxlr_release_nvdimm, cxlr);
-
-err:
- put_device(dev);
-err_bridge:
- put_device(&cxl_nvb->dev);
- cxlr->cxl_nvb = NULL;
- return rc;
-}
-
static void cxlr_dax_unregister(void *_cxlr_dax)
{
struct cxl_dax_region *cxlr_dax = _cxlr_dax;
diff --git a/drivers/cxl/core/region_pmem.c b/drivers/cxl/core/region_pmem.c
new file mode 100644
index 000000000000..b2f1e567d398
--- /dev/null
+++ b/drivers/cxl/core/region_pmem.c
@@ -0,0 +1,191 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2022 Intel Corporation. All rights reserved. */
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <cxlmem.h>
+#include <cxl.h>
+#include "core.h"
+
+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 int cxl_pmem_region_alloc(struct cxl_region *cxlr)
+{
+ struct cxl_region_params *p = &cxlr->params;
+ struct cxl_nvdimm_bridge *cxl_nvb;
+ struct device *dev;
+ int i;
+
+ guard(rwsem_read)(&cxl_rwsem.region);
+ if (p->state != CXL_CONFIG_COMMIT)
+ return -ENXIO;
+
+ struct cxl_pmem_region *cxlr_pmem __free(kfree) =
+ kzalloc_flex(*cxlr_pmem, mapping, p->nr_targets);
+ if (!cxlr_pmem)
+ return -ENOMEM;
+
+ cxlr_pmem->hpa_range.start = p->res->start;
+ cxlr_pmem->hpa_range.end = p->res->end;
+
+ /* Snapshot the region configuration underneath the cxl_rwsem.region */
+ 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];
+
+ /*
+ * Regions never span CXL root devices, so by definition the
+ * bridge for one device is the same for all.
+ */
+ if (i == 0) {
+ cxl_nvb = cxl_find_nvdimm_bridge(cxlmd->endpoint);
+ if (!cxl_nvb)
+ return -ENODEV;
+ cxlr->cxl_nvb = cxl_nvb;
+ }
+ 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;
+ 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;
+ cxlr_pmem->cxlr = cxlr;
+ cxlr->cxlr_pmem = no_free_ptr(cxlr_pmem);
+
+ return 0;
+}
+
+static void cxlr_pmem_unregister(void *_cxlr_pmem)
+{
+ struct cxl_pmem_region *cxlr_pmem = _cxlr_pmem;
+ struct cxl_region *cxlr = cxlr_pmem->cxlr;
+ struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
+
+ /*
+ * Either the bridge is in ->remove() context under the device_lock(),
+ * or cxlr_release_nvdimm() is cancelling the bridge's release action
+ * for @cxlr_pmem and doing it itself (while manually holding the bridge
+ * lock).
+ */
+ device_lock_assert(&cxl_nvb->dev);
+ cxlr->cxlr_pmem = NULL;
+ cxlr_pmem->cxlr = NULL;
+ device_unregister(&cxlr_pmem->dev);
+}
+
+static void cxlr_release_nvdimm(void *_cxlr)
+{
+ struct cxl_region *cxlr = _cxlr;
+ struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
+
+ scoped_guard(device, &cxl_nvb->dev) {
+ if (cxlr->cxlr_pmem)
+ devm_release_action(&cxl_nvb->dev, cxlr_pmem_unregister,
+ cxlr->cxlr_pmem);
+ }
+ cxlr->cxl_nvb = NULL;
+ put_device(&cxl_nvb->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.
+ */
+int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
+{
+ struct cxl_pmem_region *cxlr_pmem;
+ struct cxl_nvdimm_bridge *cxl_nvb;
+ struct device *dev;
+ int rc;
+
+ rc = cxl_pmem_region_alloc(cxlr);
+ if (rc)
+ return rc;
+ cxlr_pmem = cxlr->cxlr_pmem;
+ cxl_nvb = cxlr->cxl_nvb;
+
+ 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));
+
+ scoped_guard(device, &cxl_nvb->dev) {
+ if (cxl_nvb->dev.driver)
+ rc = devm_add_action_or_reset(&cxl_nvb->dev,
+ cxlr_pmem_unregister,
+ cxlr_pmem);
+ else
+ rc = -ENXIO;
+ }
+
+ if (rc)
+ goto err_bridge;
+
+ /* @cxlr carries a reference on @cxl_nvb until cxlr_release_nvdimm */
+ return devm_add_action_or_reset(&cxlr->dev, cxlr_release_nvdimm, cxlr);
+
+err:
+ put_device(dev);
+err_bridge:
+ put_device(&cxl_nvb->dev);
+ cxlr->cxl_nvb = NULL;
+ return rc;
+}
diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild
index 53d84a6874b7..f53d79a05661 100644
--- 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) += $(CXL_CORE_SRC)/region.o
+cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o $(CXL_CORE_SRC)/region_pmem.o
cxl_core-$(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
--
2.53.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH v5 1/3] cxl/core/region: move pmem region driver logic into region_pmem.c
2026-03-27 2:02 ` [PATCH v5 1/3] cxl/core/region: move pmem region driver logic into region_pmem.c Gregory Price
@ 2026-03-27 16:56 ` Ira Weiny
0 siblings, 0 replies; 12+ messages in thread
From: Ira Weiny @ 2026-03-27 16:56 UTC (permalink / raw)
To: Gregory Price, linux-cxl
Cc: linux-kernel, kernel-team, dave, jonathan.cameron, dave.jiang,
alison.schofield, vishal.l.verma, ira.weiny, dan.j.williams
Gregory Price wrote:
> core/region.c is overloaded with per-region control logic (pmem, dax,
> sysram, etc). Move the pmem region driver logic from region.c into
> region_pmem.c make it clear that this code only applies to pmem regions.
>
> No functional changes.
>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
> 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>
> ---
[snip]
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c
2026-03-27 2:02 [PATCH v5 0/3] pull region-specific logic into new files Gregory Price
2026-03-27 2:02 ` [PATCH v5 1/3] cxl/core/region: move pmem region driver logic into region_pmem.c Gregory Price
@ 2026-03-27 2:02 ` Gregory Price
2026-03-27 16:57 ` Ira Weiny
2026-04-11 0:02 ` Anisa Su
2026-03-27 2:02 ` [PATCH v5 3/3] cxl/core: use cleanup.h for devm_cxl_add_dax_region Gregory Price
2026-03-27 18:57 ` [PATCH v5 0/3] pull region-specific logic into new files Dave Jiang
3 siblings, 2 replies; 12+ messages in thread
From: Gregory Price @ 2026-03-27 2:02 UTC (permalink / raw)
To: linux-cxl
Cc: linux-kernel, kernel-team, dave, jonathan.cameron, dave.jiang,
alison.schofield, vishal.l.verma, ira.weiny, dan.j.williams
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>
---
drivers/cxl/core/Makefile | 2 +-
drivers/cxl/core/core.h | 1 +
drivers/cxl/core/region.c | 99 ------------------------------
drivers/cxl/core/region_dax.c | 109 ++++++++++++++++++++++++++++++++++
tools/testing/cxl/Kbuild | 2 +-
5 files changed, 112 insertions(+), 101 deletions(-)
create mode 100644 drivers/cxl/core/region_dax.c
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index f73776fe323b..ce7213818d3c 100644
--- 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 ef03966eeabd..82ca3a476708 100644
--- 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 72aee1408efb..6a2ef3475764 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -3436,105 +3436,6 @@ 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
index 000000000000..fe367759ac69
--- /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 f53d79a05661..d2b291e5f842 100644
--- 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
--
2.53.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c
2026-03-27 2:02 ` [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c Gregory Price
@ 2026-03-27 16:57 ` Ira Weiny
2026-04-11 0:02 ` Anisa Su
1 sibling, 0 replies; 12+ messages in thread
From: Ira Weiny @ 2026-03-27 16:57 UTC (permalink / raw)
To: Gregory Price, linux-cxl
Cc: linux-kernel, kernel-team, dave, jonathan.cameron, dave.jiang,
alison.schofield, vishal.l.verma, ira.weiny, dan.j.williams
Gregory Price wrote:
> 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.
>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
> 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>
> ---
[snip]
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c
2026-03-27 2:02 ` [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c Gregory Price
2026-03-27 16:57 ` Ira Weiny
@ 2026-04-11 0:02 ` Anisa Su
2026-04-11 0:26 ` Dave Jiang
2026-04-11 5:09 ` Gregory Price
1 sibling, 2 replies; 12+ messages in thread
From: Anisa Su @ 2026-04-11 0:02 UTC (permalink / raw)
To: Gregory Price
Cc: linux-cxl, linux-kernel, kernel-team, dave, jonathan.cameron,
dave.jiang, alison.schofield, vishal.l.verma, ira.weiny,
dan.j.williams
On Thu, Mar 26, 2026 at 10:02:02PM -0400, Gregory Price wrote:
> 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>
> ---
> drivers/cxl/core/Makefile | 2 +-
> drivers/cxl/core/core.h | 1 +
> drivers/cxl/core/region.c | 99 ------------------------------
> drivers/cxl/core/region_dax.c | 109 ++++++++++++++++++++++++++++++++++
> tools/testing/cxl/Kbuild | 2 +-
> 5 files changed, 112 insertions(+), 101 deletions(-)
> create mode 100644 drivers/cxl/core/region_dax.c
>
> diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
> index f73776fe323b..ce7213818d3c 100644
> --- 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 ef03966eeabd..82ca3a476708 100644
> --- 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 72aee1408efb..6a2ef3475764 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -3436,105 +3436,6 @@ 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
> index 000000000000..fe367759ac69
> --- /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;
cxlr->cxlr_dax = cxlr_dax;
Running into segfaults without this ^
> + 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 f53d79a05661..d2b291e5f842 100644
> --- 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) += $(CXL_CORE_SRC)/edac.o
> --
> 2.53.0
>
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c
2026-04-11 0:02 ` Anisa Su
@ 2026-04-11 0:26 ` Dave Jiang
2026-04-11 5:09 ` Gregory Price
1 sibling, 0 replies; 12+ messages in thread
From: Dave Jiang @ 2026-04-11 0:26 UTC (permalink / raw)
To: Anisa Su, Gregory Price
Cc: linux-cxl, linux-kernel, kernel-team, dave, jonathan.cameron,
alison.schofield, vishal.l.verma, ira.weiny, dan.j.williams
On 4/10/26 5:02 PM, Anisa Su wrote:
> On Thu, Mar 26, 2026 at 10:02:02PM -0400, Gregory Price wrote:
>> core/region.c is overloaded with per-region control logic (pmem, dax,
>> sysram, etc). Move the CXL DAX region device infrastructure from
>> region.c into a new region_dax.c file.
>>
>> This will also allow us to add additional dax-driver integration paths
>> that don't further dirty the core region.c logic.
>>
>> No functional changes.
>>
>> Signed-off-by: Gregory Price <gourry@gourry.net>
>> Co-developed-by: Ira Weiny <ira.weiny@intel.com>
>> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
>> ---
>> drivers/cxl/core/Makefile | 2 +-
>> drivers/cxl/core/core.h | 1 +
>> drivers/cxl/core/region.c | 99 ------------------------------
>> drivers/cxl/core/region_dax.c | 109 ++++++++++++++++++++++++++++++++++
>> tools/testing/cxl/Kbuild | 2 +-
>> 5 files changed, 112 insertions(+), 101 deletions(-)
>> create mode 100644 drivers/cxl/core/region_dax.c
>>
>> diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
>> index f73776fe323b..ce7213818d3c 100644
>> --- a/drivers/cxl/core/Makefile
>> +++ b/drivers/cxl/core/Makefile
>> @@ -15,7 +15,7 @@ cxl_core-y += hdm.o
>> cxl_core-y += pmu.o
>> cxl_core-y += cdat.o
>> cxl_core-$(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 ef03966eeabd..82ca3a476708 100644
>> --- 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 72aee1408efb..6a2ef3475764 100644
>> --- a/drivers/cxl/core/region.c
>> +++ b/drivers/cxl/core/region.c
>> @@ -3436,105 +3436,6 @@ 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
>> index 000000000000..fe367759ac69
>> --- /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;
> cxlr->cxlr_dax = cxlr_dax;
>
> Running into segfaults without this ^
Can you pls create a fixes patch?
DJ
>> + 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 f53d79a05661..d2b291e5f842 100644
>> --- 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
>> --
>> 2.53.0
>>
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c
2026-04-11 0:02 ` Anisa Su
2026-04-11 0:26 ` Dave Jiang
@ 2026-04-11 5:09 ` Gregory Price
2026-04-11 17:39 ` Dan Williams
1 sibling, 1 reply; 12+ messages in thread
From: Gregory Price @ 2026-04-11 5:09 UTC (permalink / raw)
To: Anisa Su
Cc: linux-cxl, linux-kernel, kernel-team, dave, jonathan.cameron,
dave.jiang, alison.schofield, vishal.l.verma, ira.weiny,
dan.j.williams
On Fri, Apr 10, 2026 at 05:02:00PM -0700, Anisa Su wrote:
> > +
> > + cxlr_dax->hpa_range.start = p->res->start;
> > + cxlr_dax->hpa_range.end = p->res->end;
> > +
> > + dev = &cxlr_dax->dev;
> > + cxlr_dax->cxlr = cxlr;
> cxlr->cxlr_dax = cxlr_dax;
>
> Running into segfaults without this ^
This should have been a purely non-functional change (the code is just
moving from A to B without changes).
That would mean the original code should run into this too unless I
mucked up the move.
~Gregory
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c
2026-04-11 5:09 ` Gregory Price
@ 2026-04-11 17:39 ` Dan Williams
0 siblings, 0 replies; 12+ messages in thread
From: Dan Williams @ 2026-04-11 17:39 UTC (permalink / raw)
To: Gregory Price
Cc: linux-cxl, linux-kernel, kernel-team, dave, jonathan.cameron,
dave.jiang, alison.schofield, vishal.l.verma, ira.weiny
Gregory Price wrote:
> On Fri, Apr 10, 2026 at 05:02:00PM -0700, Anisa Su wrote:
> > > +
> > > + cxlr_dax->hpa_range.start = p->res->start;
> > > + cxlr_dax->hpa_range.end = p->res->end;
> > > +
> > > + dev = &cxlr_dax->dev;
> > > + cxlr_dax->cxlr = cxlr;
> > cxlr->cxlr_dax = cxlr_dax;
> >
> > Running into segfaults without this ^
>
> This should have been a purely non-functional change (the code is just
> moving from A to B without changes).
>
> That would mean the original code should run into this too unless I
> mucked up the move.
I do not think you mucked anything up ->cxlr_dax does not exist in mainline.
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v5 3/3] cxl/core: use cleanup.h for devm_cxl_add_dax_region
2026-03-27 2:02 [PATCH v5 0/3] pull region-specific logic into new files Gregory Price
2026-03-27 2:02 ` [PATCH v5 1/3] cxl/core/region: move pmem region driver logic into region_pmem.c Gregory Price
2026-03-27 2:02 ` [PATCH v5 2/3] cxl/core/region: move dax region device logic into region_dax.c Gregory Price
@ 2026-03-27 2:02 ` Gregory Price
2026-03-27 17:05 ` Ira Weiny
2026-03-27 18:57 ` [PATCH v5 0/3] pull region-specific logic into new files Dave Jiang
3 siblings, 1 reply; 12+ messages in thread
From: Gregory Price @ 2026-03-27 2:02 UTC (permalink / raw)
To: linux-cxl
Cc: linux-kernel, kernel-team, dave, jonathan.cameron, dave.jiang,
alison.schofield, vishal.l.verma, ira.weiny, dan.j.williams
Cleanup the gotos in the function. No functional change.
Signed-off-by: Gregory Price <gourry@gourry.net>
---
drivers/cxl/core/region_dax.c | 13 +++++--------
drivers/cxl/cxl.h | 1 +
2 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/drivers/cxl/core/region_dax.c b/drivers/cxl/core/region_dax.c
index fe367759ac69..de04f78f6ad8 100644
--- a/drivers/cxl/core/region_dax.c
+++ b/drivers/cxl/core/region_dax.c
@@ -81,29 +81,26 @@ static void cxlr_dax_unregister(void *_cxlr_dax)
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);
+ struct cxl_dax_region *cxlr_dax __free(put_cxl_dax_region) =
+ 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;
+ return rc;
rc = device_add(dev);
if (rc)
- goto err;
+ return rc;
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;
+ no_free_ptr(cxlr_dax));
}
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index f08be12e0e53..249a2f5ffc7b 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -712,6 +712,7 @@ DEFINE_FREE(put_cxl_root, struct cxl_root *, if (_T) put_device(&_T->port.dev))
DEFINE_FREE(put_cxl_port, struct cxl_port *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
DEFINE_FREE(put_cxl_root_decoder, struct cxl_root_decoder *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->cxlsd.cxld.dev))
DEFINE_FREE(put_cxl_region, struct cxl_region *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
+DEFINE_FREE(put_cxl_dax_region, struct cxl_dax_region *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
void cxl_bus_rescan(void);
--
2.53.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH v5 3/3] cxl/core: use cleanup.h for devm_cxl_add_dax_region
2026-03-27 2:02 ` [PATCH v5 3/3] cxl/core: use cleanup.h for devm_cxl_add_dax_region Gregory Price
@ 2026-03-27 17:05 ` Ira Weiny
0 siblings, 0 replies; 12+ messages in thread
From: Ira Weiny @ 2026-03-27 17:05 UTC (permalink / raw)
To: Gregory Price, linux-cxl
Cc: linux-kernel, kernel-team, dave, jonathan.cameron, dave.jiang,
alison.schofield, vishal.l.verma, ira.weiny, dan.j.williams
Gregory Price wrote:
> Cleanup the gotos in the function. No functional change.
>
> Signed-off-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[snip]
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v5 0/3] pull region-specific logic into new files
2026-03-27 2:02 [PATCH v5 0/3] pull region-specific logic into new files Gregory Price
` (2 preceding siblings ...)
2026-03-27 2:02 ` [PATCH v5 3/3] cxl/core: use cleanup.h for devm_cxl_add_dax_region Gregory Price
@ 2026-03-27 18:57 ` Dave Jiang
3 siblings, 0 replies; 12+ messages in thread
From: Dave Jiang @ 2026-03-27 18:57 UTC (permalink / raw)
To: Gregory Price, linux-cxl
Cc: linux-kernel, kernel-team, dave, jonathan.cameron,
alison.schofield, vishal.l.verma, ira.weiny, dan.j.williams
On 3/26/26 7:02 PM, Gregory Price wrote:
> cxl/core/region.c presently contains logic to handle cxl_region,
> cxl_pmem_region, and cxl_dax_region. The cxl_pmem_region and
> cxl_dax_region management code deserves new files to make it clear
> that this logic applies to a specific types of regions.
>
> This also breaks up development space so fewer conflicts can occur, and
> it becomes clear where changes are actually happening.
>
> I snuck in a cleanup.h fixup for devm_cxl_add_dax_region to tidy up some
> of the existing functions.
>
> v4 -> v5: Ira test fixes
> Jonathan nit fixes
>
> v3 -> v4: address DJ's feedback on cleanup.h patch:
> move __free() declaration to assignment point
> restore local dev variable
>
> v2 -> v3: renamed from x_region to region_x because it's prettier
> added cleanup.h
> small nits asked for by Jonathan (commas)
>
> Gregory Price (3):
> cxl/core/region: move pmem region driver logic into region_pmem.c
> cxl/core/region: move dax region device logic into region_dax.c
> cxl/core: use cleanup.h for devm_cxl_add_dax_region
>
> drivers/cxl/core/Makefile | 2 +-
> drivers/cxl/core/core.h | 2 +
> drivers/cxl/core/region.c | 283 ---------------------------------
> drivers/cxl/core/region_dax.c | 106 ++++++++++++
> drivers/cxl/core/region_pmem.c | 191 ++++++++++++++++++++++
> drivers/cxl/cxl.h | 1 +
> tools/testing/cxl/Kbuild | 2 +-
> 7 files changed, 302 insertions(+), 285 deletions(-)
> create mode 100644 drivers/cxl/core/region_dax.c
> create mode 100644 drivers/cxl/core/region_pmem.c
>
I applied to for-7.1/cxl-region-refactor branch and pushed to the cxl.git so it gets 0-day coverage. But I'm going hold off until the end to merge this in case of merge conflicts.
29990ab5cb40 cxl/core: use cleanup.h for devm_cxl_add_dax_region
d747cf98f091 cxl/core/region: move dax region device logic into region_dax.c
8a1ec5fb2360 cxl/core/region: move pmem region driver logic into region_pmem.c
^ permalink raw reply [flat|nested] 12+ messages in thread