Merge branch 'for-7.0/cxl-init' into cxl-for-next

Merge in patches to support several patch series such as Soft Reserve
handling, type2 accelerator enabling, and LSA 2.1 labeling support.
Mainly addition of cxl_memdev_attach() to allow the memdev probe
to make a decision of proceed/fail depending success of CXL topology
enumeration.

dax/hmem, e820, resource: Defer Soft Reserved insertion until hmem is ready
cxl/mem: Introduce cxl_memdev_attach for CXL-dependent operation
cxl/mem: Drop @host argument to devm_cxl_add_memdev()
cxl/mem: Convert devm_cxl_add_memdev() to scope-based-cleanup
cxl/port: Arrange for always synchronous endpoint attach
cxl/mem: Arrange for always-synchronous memdev attach
cxl/mem: Fix devm_cxl_memdev_edac_release() confusion

Author: davejiang

arch/x86/kernel/e820.c

@@ -1151,11 +1151,18 @@ void __init e820__reserve_resources_late(void)
 	int i;
 	struct resource *res;
 
-	res = e820_res;
-	for (i = 0; i < e820_table->nr_entries; i++) {
-		if (!res->parent && res->end)
+	for (i = 0, res = e820_res; i < e820_table->nr_entries; i++, res++) {
+		/* skip added or uninitialized resources */
+		if (res->parent || !res->end)
+			continue;
+
+		/* set aside soft-reserved resources for driver consideration */
+		if (res->desc == IORES_DESC_SOFT_RESERVED) {
+			insert_resource_expand_to_fit(&soft_reserve_resource, res);
+		} else {
+			/* publish the rest immediately */
 			insert_resource_expand_to_fit(&iomem_resource, res);
-		res++;
+		}
 	}
 
 	/*

drivers/cxl/Kconfig

@@ -22,6 +22,7 @@ if CXL_BUS
 config CXL_PCI
 	tristate "PCI manageability"
 	default CXL_BUS
+	select CXL_MEM
 	help
 	  The CXL specification defines a "CXL memory device" sub-class in the
 	  PCI "memory controller" base class of devices. Device's identified by
@@ -89,7 +90,6 @@ config CXL_PMEM
 
 config CXL_MEM
 	tristate "CXL: Memory Expansion"
-	depends on CXL_PCI
 	default CXL_BUS
 	help
 	  The CXL.mem protocol allows a device to act as a provider of "System

drivers/cxl/core/edac.c

@@ -1988,6 +1988,40 @@ static int cxl_memdev_soft_ppr_init(struct cxl_memdev *cxlmd,
 	return 0;
 }
 
+static void err_rec_free(void *_cxlmd)
+{
+	struct cxl_memdev *cxlmd = _cxlmd;
+	struct cxl_mem_err_rec *array_rec = cxlmd->err_rec_array;
+	struct cxl_event_gen_media *rec_gen_media;
+	struct cxl_event_dram *rec_dram;
+	unsigned long index;
+
+	cxlmd->err_rec_array = NULL;
+	xa_for_each(&array_rec->rec_dram, index, rec_dram)
+		kfree(rec_dram);
+	xa_destroy(&array_rec->rec_dram);
+
+	xa_for_each(&array_rec->rec_gen_media, index, rec_gen_media)
+		kfree(rec_gen_media);
+	xa_destroy(&array_rec->rec_gen_media);
+	kfree(array_rec);
+}
+
+static int devm_cxl_memdev_setup_err_rec(struct cxl_memdev *cxlmd)
+{
+	struct cxl_mem_err_rec *array_rec =
+		kzalloc(sizeof(*array_rec), GFP_KERNEL);
+
+	if (!array_rec)
+		return -ENOMEM;
+
+	xa_init(&array_rec->rec_gen_media);
+	xa_init(&array_rec->rec_dram);
+	cxlmd->err_rec_array = array_rec;
+
+	return devm_add_action_or_reset(&cxlmd->dev, err_rec_free, cxlmd);
+}
+
 int devm_cxl_memdev_edac_register(struct cxl_memdev *cxlmd)
 {
 	struct edac_dev_feature ras_features[CXL_NR_EDAC_DEV_FEATURES];
@@ -2038,15 +2072,9 @@ int devm_cxl_memdev_edac_register(struct cxl_memdev *cxlmd)
 		}
 
 		if (repair_inst) {
-			struct cxl_mem_err_rec *array_rec =
-				devm_kzalloc(&cxlmd->dev, sizeof(*array_rec),
-					     GFP_KERNEL);
-			if (!array_rec)
-				return -ENOMEM;
-
-			xa_init(&array_rec->rec_gen_media);
-			xa_init(&array_rec->rec_dram);
-			cxlmd->err_rec_array = array_rec;
+			rc = devm_cxl_memdev_setup_err_rec(cxlmd);
+			if (rc)
+				return rc;
 		}
 	}
 
@@ -2088,22 +2116,4 @@ int devm_cxl_region_edac_register(struct cxl_region *cxlr)
 }
 EXPORT_SYMBOL_NS_GPL(devm_cxl_region_edac_register, "CXL");
 
-void devm_cxl_memdev_edac_release(struct cxl_memdev *cxlmd)
-{
-	struct cxl_mem_err_rec *array_rec = cxlmd->err_rec_array;
-	struct cxl_event_gen_media *rec_gen_media;
-	struct cxl_event_dram *rec_dram;
-	unsigned long index;
-
-	if (!IS_ENABLED(CONFIG_CXL_EDAC_MEM_REPAIR) || !array_rec)
-		return;
-
-	xa_for_each(&array_rec->rec_dram, index, rec_dram)
-		kfree(rec_dram);
-	xa_destroy(&array_rec->rec_dram);
 
-	xa_for_each(&array_rec->rec_gen_media, index, rec_gen_media)
-		kfree(rec_gen_media);
-	xa_destroy(&array_rec->rec_gen_media);
-}
-EXPORT_SYMBOL_NS_GPL(devm_cxl_memdev_edac_release, "CXL");

drivers/cxl/core/memdev.c

@@ -27,7 +27,6 @@ static void cxl_memdev_release(struct device *dev)
 	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
 
 	ida_free(&cxl_memdev_ida, cxlmd->id);
-	devm_cxl_memdev_edac_release(cxlmd);
 	kfree(cxlmd);
 }
 
@@ -642,14 +641,24 @@ static void detach_memdev(struct work_struct *work)
 	struct cxl_memdev *cxlmd;
 
 	cxlmd = container_of(work, typeof(*cxlmd), detach_work);
-	device_release_driver(&cxlmd->dev);
+
+	/*
+	 * When the creator of @cxlmd sets ->attach it indicates CXL operation
+	 * is required. In that case, @cxlmd detach escalates to parent device
+	 * detach.
+	 */
+	if (cxlmd->attach)
+		device_release_driver(cxlmd->dev.parent);
+	else
+		device_release_driver(&cxlmd->dev);
 	put_device(&cxlmd->dev);
 }
 
 static struct lock_class_key cxl_memdev_key;
 
 static struct cxl_memdev *cxl_memdev_alloc(struct cxl_dev_state *cxlds,
-					   const struct file_operations *fops)
+					   const struct file_operations *fops,
+					   const struct cxl_memdev_attach *attach)
 {
 	struct cxl_memdev *cxlmd;
 	struct device *dev;
@@ -665,6 +674,8 @@ static struct cxl_memdev *cxl_memdev_alloc(struct cxl_dev_state *cxlds,
 		goto err;
 	cxlmd->id = rc;
 	cxlmd->depth = -1;
+	cxlmd->attach = attach;
+	cxlmd->endpoint = ERR_PTR(-ENXIO);
 
 	dev = &cxlmd->dev;
 	device_initialize(dev);
@@ -1051,50 +1062,84 @@ static const struct file_operations cxl_memdev_fops = {
 	.llseek = noop_llseek,
 };
 
-struct cxl_memdev *devm_cxl_add_memdev(struct device *host,
-				       struct cxl_dev_state *cxlds)
+/*
+ * Activate ioctl operations, no cxl_memdev_rwsem manipulation needed as this is
+ * ordered with cdev_add() publishing the device.
+ */
+static int cxlmd_add(struct cxl_memdev *cxlmd, struct cxl_dev_state *cxlds)
+{
+	int rc;
+
+	cxlmd->cxlds = cxlds;
+	cxlds->cxlmd = cxlmd;
+
+	rc = cdev_device_add(&cxlmd->cdev, &cxlmd->dev);
+	if (rc) {
+		/*
+		 * The cdev was briefly live, shutdown any ioctl operations that
+		 * saw that state.
+		 */
+		cxl_memdev_shutdown(&cxlmd->dev);
+		return rc;
+	}
+
+	return 0;
+}
+
+DEFINE_FREE(put_cxlmd, struct cxl_memdev *,
+	    if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
+
+static struct cxl_memdev *cxl_memdev_autoremove(struct cxl_memdev *cxlmd)
+{
+	int rc;
+
+	/*
+	 * If @attach is provided fail if the driver is not attached upon
+	 * return. Note that failure here could be the result of a race to
+	 * teardown the CXL port topology. I.e. cxl_mem_probe() could have
+	 * succeeded and then cxl_mem unbound before the lock is acquired.
+	 */
+	guard(device)(&cxlmd->dev);
+	if (cxlmd->attach && !cxlmd->dev.driver) {
+		cxl_memdev_unregister(cxlmd);
+		return ERR_PTR(-ENXIO);
+	}
+
+	rc = devm_add_action_or_reset(cxlmd->cxlds->dev, cxl_memdev_unregister,
+				      cxlmd);
+	if (rc)
+		return ERR_PTR(rc);
+
+	return cxlmd;
+}
+
+/*
+ * Core helper for devm_cxl_add_memdev() that wants to both create a device and
+ * assert to the caller that upon return cxl_mem::probe() has been invoked.
+ */
+struct cxl_memdev *__devm_cxl_add_memdev(struct cxl_dev_state *cxlds,
+					 const struct cxl_memdev_attach *attach)
 {
-	struct cxl_memdev *cxlmd;
 	struct device *dev;
-	struct cdev *cdev;
 	int rc;
 
-	cxlmd = cxl_memdev_alloc(cxlds, &cxl_memdev_fops);
+	struct cxl_memdev *cxlmd __free(put_cxlmd) =
+		cxl_memdev_alloc(cxlds, &cxl_memdev_fops, attach);
 	if (IS_ERR(cxlmd))
 		return cxlmd;
 
 	dev = &cxlmd->dev;
 	rc = dev_set_name(dev, "mem%d", cxlmd->id);
 	if (rc)
-		goto err;
-
-	/*
-	 * Activate ioctl operations, no cxl_memdev_rwsem manipulation
-	 * needed as this is ordered with cdev_add() publishing the device.
-	 */
-	cxlmd->cxlds = cxlds;
-	cxlds->cxlmd = cxlmd;
-
-	cdev = &cxlmd->cdev;
-	rc = cdev_device_add(cdev, dev);
-	if (rc)
-		goto err;
+		return ERR_PTR(rc);
 
-	rc = devm_add_action_or_reset(host, cxl_memdev_unregister, cxlmd);
+	rc = cxlmd_add(cxlmd, cxlds);
 	if (rc)
 		return ERR_PTR(rc);
-	return cxlmd;
 
-err:
-	/*
-	 * The cdev was briefly live, shutdown any ioctl operations that
-	 * saw that state.
-	 */
-	cxl_memdev_shutdown(dev);
-	put_device(dev);
-	return ERR_PTR(rc);
+	return cxl_memdev_autoremove(no_free_ptr(cxlmd));
 }
-EXPORT_SYMBOL_NS_GPL(devm_cxl_add_memdev, "CXL");
+EXPORT_SYMBOL_FOR_MODULES(__devm_cxl_add_memdev, "cxl_mem");
 
 static void sanitize_teardown_notifier(void *data)
 {

drivers/cxl/cxl.h

@@ -780,6 +780,8 @@ struct cxl_port *devm_cxl_add_port(struct device *host,
 				   struct cxl_dport *parent_dport);
 struct cxl_root *devm_cxl_add_root(struct device *host,
 				   const struct cxl_root_ops *ops);
+int devm_cxl_add_endpoint(struct device *host, struct cxl_memdev *cxlmd,
+			  struct cxl_dport *parent_dport);
 struct cxl_root *find_cxl_root(struct cxl_port *port);
 
 DEFINE_FREE(put_cxl_root, struct cxl_root *, if (_T) put_device(&_T->port.dev))

drivers/cxl/cxlmem.h

@@ -34,6 +34,10 @@
 	(FIELD_GET(CXLMDEV_RESET_NEEDED_MASK, status) !=                       \
 	 CXLMDEV_RESET_NEEDED_NOT)
 
+struct cxl_memdev_attach {
+	int (*probe)(struct cxl_memdev *cxlmd);
+};
+
 /**
  * struct cxl_memdev - CXL bus object representing a Type-3 Memory Device
  * @dev: driver core device object
@@ -43,6 +47,7 @@
  * @cxl_nvb: coordinate removal of @cxl_nvd if present
  * @cxl_nvd: optional bridge to an nvdimm if the device supports pmem
  * @endpoint: connection to the CXL port topology for this memory device
+ * @attach: creator of this memdev depends on CXL link attach to operate
  * @id: id number of this memdev instance.
  * @depth: endpoint port depth
  * @scrub_cycle: current scrub cycle set for this device
@@ -59,11 +64,12 @@ struct cxl_memdev {
 	struct cxl_nvdimm_bridge *cxl_nvb;
 	struct cxl_nvdimm *cxl_nvd;
 	struct cxl_port *endpoint;
+	const struct cxl_memdev_attach *attach;
 	int id;
 	int depth;
 	u8 scrub_cycle;
 	int scrub_region_id;
-	void *err_rec_array;
+	struct cxl_mem_err_rec *err_rec_array;
 };
 
 static inline struct cxl_memdev *to_cxl_memdev(struct device *dev)
@@ -95,8 +101,10 @@ 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);
+struct cxl_memdev *__devm_cxl_add_memdev(struct cxl_dev_state *cxlds,
+					 const struct cxl_memdev_attach *attach);
+struct cxl_memdev *devm_cxl_add_memdev(struct cxl_dev_state *cxlds,
+				       const struct cxl_memdev_attach *attach);
 int devm_cxl_sanitize_setup_notifier(struct device *host,
 				     struct cxl_memdev *cxlmd);
 struct cxl_memdev_state;
@@ -877,7 +885,6 @@ int devm_cxl_memdev_edac_register(struct cxl_memdev *cxlmd);
 int devm_cxl_region_edac_register(struct cxl_region *cxlr);
 int cxl_store_rec_gen_media(struct cxl_memdev *cxlmd, union cxl_event *evt);
 int cxl_store_rec_dram(struct cxl_memdev *cxlmd, union cxl_event *evt);
-void devm_cxl_memdev_edac_release(struct cxl_memdev *cxlmd);
 #else
 static inline int devm_cxl_memdev_edac_register(struct cxl_memdev *cxlmd)
 { return 0; }
@@ -889,8 +896,6 @@ static inline int cxl_store_rec_gen_media(struct cxl_memdev *cxlmd,
 static inline int cxl_store_rec_dram(struct cxl_memdev *cxlmd,
 				     union cxl_event *evt)
 { return 0; }
-static inline void devm_cxl_memdev_edac_release(struct cxl_memdev *cxlmd)
-{ return; }
 #endif
 
 #ifdef CONFIG_CXL_SUSPEND