[v13,09/22] cxl: prepare memdev creation for type2

Commit Message

Lucero Palau, Alejandro April 14, 2025, 3:13 p.m. UTC

From: Alejandro Lucero <[e-mail]>

Current cxl core is relying on a CXL_DEVTYPE_CLASSMEM type device when
creating a memdev leading to problems when obtaining cxl_memdev_state
references from a CXL_DEVTYPE_DEVMEM type.

Modify check for obtaining cxl_memdev_state adding CXL_DEVTYPE_DEVMEM
support.

Make devm_cxl_add_memdev accessible from a accel driver.

Signed-off-by: Alejandro Lucero <[e-mail]>
Reviewed-by: Ben Cheatham <[e-mail]>
Reviewed-by: Jonathan Cameron <[e-mail]>
Reviewed-by: Dave Jiang <[e-mail]>
---
 drivers/cxl/core/memdev.c | 15 +++++++++++++--
 drivers/cxl/cxlmem.h      |  2 --
 drivers/cxl/mem.c         | 25 +++++++++++++++++++------
 include/cxl/cxl.h         |  2 ++
 4 files changed, 34 insertions(+), 10 deletions(-)

Patch

diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
index 6cc732aeb9de..31af5c1ebe11 100644
--- a/drivers/cxl/core/memdev.c
+++ b/drivers/cxl/core/memdev.c
@@ -7,6 +7,7 @@ 
 #include <linux/slab.h>
 #include <linux/idr.h>
 #include <linux/pci.h>
+#include <cxl/cxl.h>
 #include <cxlmem.h>
 #include "trace.h"
 #include "core.h"
@@ -562,9 +563,16 @@  static const struct device_type cxl_memdev_type = {
 	.groups = cxl_memdev_attribute_groups,
 };
 
+static const struct device_type cxl_accel_memdev_type = {
+	.name = "cxl_accel_memdev",
+	.release = cxl_memdev_release,
+	.devnode = cxl_memdev_devnode,
+};
+
 bool is_cxl_memdev(const struct device *dev)
 {
-	return dev->type == &cxl_memdev_type;
+	return (dev->type == &cxl_memdev_type ||
+		dev->type == &cxl_accel_memdev_type);
 }
 EXPORT_SYMBOL_NS_GPL(is_cxl_memdev, "CXL");
 
@@ -689,7 +697,10 @@  static struct cxl_memdev *cxl_memdev_alloc(struct cxl_dev_state *cxlds,
 	dev->parent = cxlds->dev;
 	dev->bus = &cxl_bus_type;
 	dev->devt = MKDEV(cxl_mem_major, cxlmd->id);
-	dev->type = &cxl_memdev_type;
+	if (cxlds->type == CXL_DEVTYPE_DEVMEM)
+		dev->type = &cxl_accel_memdev_type;
+	else
+		dev->type = &cxl_memdev_type;
 	device_set_pm_not_required(dev);
 	INIT_WORK(&cxlmd->detach_work, detach_memdev);
 
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index e47f51025efd..9fdaf5cf1dd9 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -88,8 +88,6 @@  static inline bool is_cxl_endpoint(struct cxl_port *port)
 	return is_cxl_memdev(port->uport_dev);
 }
 
-struct cxl_memdev *devm_cxl_add_memdev(struct device *host,
-				       struct cxl_dev_state *cxlds);
 int devm_cxl_sanitize_setup_notifier(struct device *host,
 				     struct cxl_memdev *cxlmd);
 struct cxl_memdev_state;
diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 9675243bd05b..7f39790d9d98 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -130,12 +130,18 @@  static int cxl_mem_probe(struct device *dev)
 	dentry = cxl_debugfs_create_dir(dev_name(dev));
 	debugfs_create_devm_seqfile(dev, "dpamem", dentry, cxl_mem_dpa_show);
 
-	if (test_bit(CXL_POISON_ENABLED_INJECT, mds->poison.enabled_cmds))
-		debugfs_create_file("inject_poison", 0200, dentry, cxlmd,
-				    &cxl_poison_inject_fops);
-	if (test_bit(CXL_POISON_ENABLED_CLEAR, mds->poison.enabled_cmds))
-		debugfs_create_file("clear_poison", 0200, dentry, cxlmd,
-				    &cxl_poison_clear_fops);
+	/*
+	 * Avoid poison debugfs files for Type2 devices as they rely on
+	 * cxl_memdev_state.
+	 */
+	if (mds) {
+		if (test_bit(CXL_POISON_ENABLED_INJECT, mds->poison.enabled_cmds))
+			debugfs_create_file("inject_poison", 0200, dentry, cxlmd,
+					    &cxl_poison_inject_fops);
+		if (test_bit(CXL_POISON_ENABLED_CLEAR, mds->poison.enabled_cmds))
+			debugfs_create_file("clear_poison", 0200, dentry, cxlmd,
+					    &cxl_poison_clear_fops);
+	}
 
 	rc = devm_add_action_or_reset(dev, remove_debugfs, dentry);
 	if (rc)
@@ -219,6 +225,13 @@  static umode_t cxl_mem_visible(struct kobject *kobj, struct attribute *a, int n)
 	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
 
+	/*
+	 * Avoid poison sysfs files for Type2 devices as they rely on
+	 * cxl_memdev_state.
+	 */
+	if (!mds)
+		return 0;
+
 	if (a == &dev_attr_trigger_poison_list.attr)
 		if (!test_bit(CXL_POISON_ENABLED_LIST,
 			      mds->poison.enabled_cmds))
diff --git a/include/cxl/cxl.h b/include/cxl/cxl.h
index d1bd136fe556..879725793f38 100644
--- a/include/cxl/cxl.h
+++ b/include/cxl/cxl.h
@@ -249,4 +249,6 @@  int cxl_pci_accel_setup_regs(struct pci_dev *pdev, struct cxl_dev_state *cxlmds,
 void cxl_mem_dpa_init(struct cxl_dpa_info *info, u64 volatile_bytes,
 		      u64 persistent_bytes);
 int cxl_dpa_setup(struct cxl_dev_state *cxlds, const struct cxl_dpa_info *info);
+struct cxl_memdev *devm_cxl_add_memdev(struct device *host,
+				       struct cxl_dev_state *cxlmds);
 #endif /* __CXL_CXL_H__ */