arch/powerpc/platforms/pseries/mobility.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Support for Partition Mobility/Migration
  *
  * Copyright (C) 2010 Nathan Fontenot
  * Copyright (C) 2010 IBM Corporation
  */

 #include <linux/cpu.h>
 #include <linux/kernel.h>
 #include <linux/kobject.h>
 #include <linux/sched.h>
 #include <linux/smp.h>
 #include <linux/stat.h>
 #include <linux/completion.h>
 #include <linux/device.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/stringify.h>

 #include <asm/machdep.h>
 #include <asm/rtas.h>
 #include "pseries.h"
 #include "../../kernel/cacheinfo.h"

 static struct kobject *mobility_kobj;

 struct update_props_workarea {
 	__be32 phandle;
 	__be32 state;
 	__be64 reserved;
 	__be32 nprops;
 } __packed;

 #define NODE_ACTION_MASK	0xff000000
 #define NODE_COUNT_MASK		0x00ffffff

 #define DELETE_DT_NODE	0x01000000
 #define UPDATE_DT_NODE	0x02000000
 #define ADD_DT_NODE	0x03000000

 #define MIGRATION_SCOPE	(1)
 #define PRRN_SCOPE -2

 static int mobility_rtas_call(int token, char *buf, s32 scope)
 {
 	int rc;

 	spin_lock(&rtas_data_buf_lock);

 	memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
 	rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, scope);
 	memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);

 	spin_unlock(&rtas_data_buf_lock);
 	return rc;
 }

 static int delete_dt_node(__be32 phandle)
 {
 	struct device_node *dn;

 	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
 	if (!dn)
 		return -ENOENT;

 	dlpar_detach_node(dn);
 	of_node_put(dn);
 	return 0;
 }

 static int update_dt_property(struct device_node *dn, struct property **prop,
 			      const char *name, u32 vd, char *value)
 {
 	struct property *new_prop = *prop;
 	int more = 0;

 	/* A negative 'vd' value indicates that only part of the new property
 	 * value is contained in the buffer and we need to call
 	 * ibm,update-properties again to get the rest of the value.
 	 *
 	 * A negative value is also the two's compliment of the actual value.
 	 */
 	if (vd & 0x80000000) {
 		vd = ~vd + 1;
 		more = 1;
 	}

 	if (new_prop) {
 		/* partial property fixup */
 		char *new_data = kzalloc(new_prop->length + vd, GFP_KERNEL);
 		if (!new_data)
 			return -ENOMEM;

 		memcpy(new_data, new_prop->value, new_prop->length);
 		memcpy(new_data + new_prop->length, value, vd);

 		kfree(new_prop->value);
 		new_prop->value = new_data;
 		new_prop->length += vd;
 	} else {
 		new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
 		if (!new_prop)
 			return -ENOMEM;

 		new_prop->name = kstrdup(name, GFP_KERNEL);
 		if (!new_prop->name) {
 			kfree(new_prop);
 			return -ENOMEM;
 		}

 		new_prop->length = vd;
 		new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
 		if (!new_prop->value) {
 			kfree(new_prop->name);
 			kfree(new_prop);
 			return -ENOMEM;
 		}

 		memcpy(new_prop->value, value, vd);
 		*prop = new_prop;
 	}

 	if (!more) {
 		of_update_property(dn, new_prop);
 		*prop = NULL;
 	}

 	return 0;
 }

 static int update_dt_node(__be32 phandle, s32 scope)
 {
 	struct update_props_workarea *upwa;
 	struct device_node *dn;
 	struct property *prop = NULL;
 	int i, rc, rtas_rc;
 	char *prop_data;
 	char *rtas_buf;
 	int update_properties_token;
 	u32 nprops;
 	u32 vd;

 	update_properties_token = rtas_token("ibm,update-properties");
 	if (update_properties_token == RTAS_UNKNOWN_SERVICE)
 		return -EINVAL;

 	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
 	if (!rtas_buf)
 		return -ENOMEM;

 	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
 	if (!dn) {
 		kfree(rtas_buf);
 		return -ENOENT;
 	}

 	upwa = (struct update_props_workarea *)&rtas_buf[0];
 	upwa->phandle = phandle;

 	do {
 		rtas_rc = mobility_rtas_call(update_properties_token, rtas_buf,
 					scope);
 		if (rtas_rc < 0)
 			break;

 		prop_data = rtas_buf + sizeof(*upwa);
 		nprops = be32_to_cpu(upwa->nprops);

 		/* On the first call to ibm,update-properties for a node the
 		 * the first property value descriptor contains an empty
 		 * property name, the property value length encoded as u32,
 		 * and the property value is the node path being updated.
 		 */
 		if (*prop_data == 0) {
 			prop_data++;
 			vd = be32_to_cpu(*(__be32 *)prop_data);
 			prop_data += vd + sizeof(vd);
 			nprops--;
 		}

 		for (i = 0; i < nprops; i++) {
 			char *prop_name;

 			prop_name = prop_data;
 			prop_data += strlen(prop_name) + 1;
 			vd = be32_to_cpu(*(__be32 *)prop_data);
 			prop_data += sizeof(vd);

 			switch (vd) {
 			case 0x00000000:
 				/* name only property, nothing to do */
 				break;

 			case 0x80000000:
 				of_remove_property(dn, of_find_property(dn,
 							prop_name, NULL));
 				prop = NULL;
 				break;

 			default:
 				rc = update_dt_property(dn, &prop, prop_name,
 							vd, prop_data);
 				if (rc) {
 					printk(KERN_ERR "Could not update %s"
 					       " property\n", prop_name);
 				}

 				prop_data += vd;
 			}

 			cond_resched();
 		}

 		cond_resched();
 	} while (rtas_rc == 1);

 	of_node_put(dn);
 	kfree(rtas_buf);
 	return 0;
 }

 static int add_dt_node(__be32 parent_phandle, __be32 drc_index)
 {
 	struct device_node *dn;
 	struct device_node *parent_dn;
 	int rc;

 	parent_dn = of_find_node_by_phandle(be32_to_cpu(parent_phandle));
 	if (!parent_dn)
 		return -ENOENT;

 	dn = dlpar_configure_connector(drc_index, parent_dn);
 	if (!dn) {
 		of_node_put(parent_dn);
 		return -ENOENT;
 	}

 	rc = dlpar_attach_node(dn, parent_dn);
 	if (rc)
 		dlpar_free_cc_nodes(dn);

 	of_node_put(parent_dn);
 	return rc;
 }

 static void prrn_update_node(__be32 phandle)
 {
 	struct pseries_hp_errorlog hp_elog;
 	struct device_node *dn;

 	/*
 	 * If a node is found from a the given phandle, the phandle does not
 	 * represent the drc index of an LMB and we can ignore.
 	 */
 	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
 	if (dn) {
 		of_node_put(dn);
 		return;
 	}

 	hp_elog.resource = PSERIES_HP_ELOG_RESOURCE_MEM;
 	hp_elog.action = PSERIES_HP_ELOG_ACTION_READD;
 	hp_elog.id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
 	hp_elog._drc_u.drc_index = phandle;

 	handle_dlpar_errorlog(&hp_elog);
 }

 int pseries_devicetree_update(s32 scope)
 {
 	char *rtas_buf;
 	__be32 *data;
 	int update_nodes_token;
 	int rc;

 	update_nodes_token = rtas_token("ibm,update-nodes");
 	if (update_nodes_token == RTAS_UNKNOWN_SERVICE)
 		return -EINVAL;

 	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
 	if (!rtas_buf)
 		return -ENOMEM;

 	do {
 		rc = mobility_rtas_call(update_nodes_token, rtas_buf, scope);
 		if (rc && rc != 1)
 			break;

 		data = (__be32 *)rtas_buf + 4;
 		while (be32_to_cpu(*data) & NODE_ACTION_MASK) {
 			int i;
 			u32 action = be32_to_cpu(*data) & NODE_ACTION_MASK;
 			u32 node_count = be32_to_cpu(*data) & NODE_COUNT_MASK;

 			data++;

 			for (i = 0; i < node_count; i++) {
 				__be32 phandle = *data++;
 				__be32 drc_index;

 				switch (action) {
 				case DELETE_DT_NODE:
 					delete_dt_node(phandle);
 					break;
 				case UPDATE_DT_NODE:
 					update_dt_node(phandle, scope);

 					if (scope == PRRN_SCOPE)
 						prrn_update_node(phandle);

 					break;
 				case ADD_DT_NODE:
 					drc_index = *data++;
 					add_dt_node(phandle, drc_index);
 					break;
 				}

 				cond_resched();
 			}
 		}

 		cond_resched();
 	} while (rc == 1);

 	kfree(rtas_buf);
 	return rc;
 }

 void post_mobility_fixup(void)
 {
 	int rc;
 	int activate_fw_token;

 	activate_fw_token = rtas_token("ibm,activate-firmware");
 	if (activate_fw_token == RTAS_UNKNOWN_SERVICE) {
 		printk(KERN_ERR "Could not make post-mobility "
 		       "activate-fw call.\n");
 		return;
 	}

 	do {
 		rc = rtas_call(activate_fw_token, 0, 1, NULL);
 	} while (rtas_busy_delay(rc));

 	if (rc)
 		printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);

 	/*
 	 * We don't want CPUs to go online/offline while the device
 	 * tree is being updated.
 	 */
 	cpus_read_lock();

 	/*
 	 * It's common for the destination firmware to replace cache
 	 * nodes.  Release all of the cacheinfo hierarchy's references
 	 * before updating the device tree.
 	 */
 	cacheinfo_teardown();

 	rc = pseries_devicetree_update(MIGRATION_SCOPE);
 	if (rc)
 		printk(KERN_ERR "Post-mobility device tree update "
 			"failed: %d\n", rc);

 	cacheinfo_rebuild();

 	cpus_read_unlock();

 	/* Possibly switch to a new RFI flush type */
 	pseries_setup_rfi_flush();

 	return;
 }

 static ssize_t migration_store(struct class *class,
 			       struct class_attribute *attr, const char *buf,
 			       size_t count)
 {
 	u64 streamid;
 	int rc;

 	rc = kstrtou64(buf, 0, &streamid);
 	if (rc)
 		return rc;

 	stop_topology_update();

 	do {
 		rc = rtas_ibm_suspend_me(streamid);
 		if (rc == -EAGAIN)
 			ssleep(1);
 	} while (rc == -EAGAIN);

 	if (rc)
 		return rc;

 	post_mobility_fixup();

 	start_topology_update();

 	return count;
 }

 /*
  * Used by drmgr to determine the kernel behavior of the migration interface.
  *
  * Version 1: Performs all PAPR requirements for migration including
  *	firmware activation and device tree update.
  */
 #define MIGRATION_API_VERSION	1

 static CLASS_ATTR_WO(migration);
 static CLASS_ATTR_STRING(api_version, 0444, __stringify(MIGRATION_API_VERSION));

 static int __init mobility_sysfs_init(void)
 {
 	int rc;

 	mobility_kobj = kobject_create_and_add("mobility", kernel_kobj);
 	if (!mobility_kobj)
 		return -ENOMEM;

 	rc = sysfs_create_file(mobility_kobj, &class_attr_migration.attr);
 	if (rc)
 		pr_err("mobility: unable to create migration sysfs file (%d)\n", rc);

 	rc = sysfs_create_file(mobility_kobj, &class_attr_api_version.attr.attr);
 	if (rc)
 		pr_err("mobility: unable to create api_version sysfs file (%d)\n", rc);

 	return 0;
 }
 machine_device_initcall(pseries, mobility_sysfs_init);
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Support for Partition Mobility/Migration
	*
	* Copyright (C) 2010 Nathan Fontenot
	* Copyright (C) 2010 IBM Corporation
	*/

	#include <linux/cpu.h>
	#include <linux/kernel.h>
	#include <linux/kobject.h>
	#include <linux/sched.h>
	#include <linux/smp.h>
	#include <linux/stat.h>
	#include <linux/completion.h>
	#include <linux/device.h>
	#include <linux/delay.h>
	#include <linux/slab.h>
	#include <linux/stringify.h>

	#include <asm/machdep.h>
	#include <asm/rtas.h>
	#include "pseries.h"
	#include "../../kernel/cacheinfo.h"

	static struct kobject *mobility_kobj;

	struct update_props_workarea {
	__be32 phandle;
	__be32 state;
	__be64 reserved;
	__be32 nprops;
	} __packed;

	#define NODE_ACTION_MASK 0xff000000
	#define NODE_COUNT_MASK 0x00ffffff

	#define DELETE_DT_NODE 0x01000000
	#define UPDATE_DT_NODE 0x02000000
	#define ADD_DT_NODE 0x03000000

	#define MIGRATION_SCOPE (1)
	#define PRRN_SCOPE -2

	static int mobility_rtas_call(int token, char *buf, s32 scope)
	{
	int rc;

	spin_lock(&rtas_data_buf_lock);

	memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
	rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, scope);
	memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);

	spin_unlock(&rtas_data_buf_lock);
	return rc;
	}

	static int delete_dt_node(__be32 phandle)
	{
	struct device_node *dn;

	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
	if (!dn)
	return -ENOENT;

	dlpar_detach_node(dn);
	of_node_put(dn);
	return 0;
	}

	static int update_dt_property(struct device_node dn, struct property *prop,
	const char name, u32 vd, char value)
	{
	struct property new_prop = prop;
	int more = 0;

	/* A negative 'vd' value indicates that only part of the new property
	* value is contained in the buffer and we need to call
	* ibm,update-properties again to get the rest of the value.
	*
	* A negative value is also the two's compliment of the actual value.
	*/
	if (vd & 0x80000000) {
	vd = ~vd + 1;
	more = 1;
	}

	if (new_prop) {
	/* partial property fixup */
	char *new_data = kzalloc(new_prop->length + vd, GFP_KERNEL);
	if (!new_data)
	return -ENOMEM;

	memcpy(new_data, new_prop->value, new_prop->length);
	memcpy(new_data + new_prop->length, value, vd);

	kfree(new_prop->value);
	new_prop->value = new_data;
	new_prop->length += vd;
	} else {
	new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
	if (!new_prop)
	return -ENOMEM;

	new_prop->name = kstrdup(name, GFP_KERNEL);
	if (!new_prop->name) {
	kfree(new_prop);
	return -ENOMEM;
	}

	new_prop->length = vd;
	new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
	if (!new_prop->value) {
	kfree(new_prop->name);
	kfree(new_prop);
	return -ENOMEM;
	}

	memcpy(new_prop->value, value, vd);
	*prop = new_prop;
	}

	if (!more) {
	of_update_property(dn, new_prop);
	*prop = NULL;
	}

	return 0;
	}

	static int update_dt_node(__be32 phandle, s32 scope)
	{
	struct update_props_workarea *upwa;
	struct device_node *dn;
	struct property *prop = NULL;
	int i, rc, rtas_rc;
	char *prop_data;
	char *rtas_buf;
	int update_properties_token;
	u32 nprops;
	u32 vd;

	update_properties_token = rtas_token("ibm,update-properties");
	if (update_properties_token == RTAS_UNKNOWN_SERVICE)
	return -EINVAL;

	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
	if (!rtas_buf)
	return -ENOMEM;

	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
	if (!dn) {
	kfree(rtas_buf);
	return -ENOENT;
	}

	upwa = (struct update_props_workarea *)&rtas_buf[0];
	upwa->phandle = phandle;

	do {
	rtas_rc = mobility_rtas_call(update_properties_token, rtas_buf,
	scope);
	if (rtas_rc < 0)
	break;

	prop_data = rtas_buf + sizeof(*upwa);
	nprops = be32_to_cpu(upwa->nprops);

	/* On the first call to ibm,update-properties for a node the
	* the first property value descriptor contains an empty
	* property name, the property value length encoded as u32,
	* and the property value is the node path being updated.
	*/
	if (*prop_data == 0) {
	prop_data++;
	vd = be32_to_cpu((__be32 )prop_data);
	prop_data += vd + sizeof(vd);
	nprops--;
	}

	for (i = 0; i < nprops; i++) {
	char *prop_name;

	prop_name = prop_data;
	prop_data += strlen(prop_name) + 1;
	vd = be32_to_cpu((__be32 )prop_data);
	prop_data += sizeof(vd);

	switch (vd) {
	case 0x00000000:
	/* name only property, nothing to do */
	break;

	case 0x80000000:
	of_remove_property(dn, of_find_property(dn,
	prop_name, NULL));
	prop = NULL;
	break;

	default:
	rc = update_dt_property(dn, &prop, prop_name,
	vd, prop_data);
	if (rc) {
	printk(KERN_ERR "Could not update %s"
	" property\n", prop_name);
	}

	prop_data += vd;
	}

	cond_resched();
	}

	cond_resched();
	} while (rtas_rc == 1);

	of_node_put(dn);
	kfree(rtas_buf);
	return 0;
	}

	static int add_dt_node(__be32 parent_phandle, __be32 drc_index)
	{
	struct device_node *dn;
	struct device_node *parent_dn;
	int rc;

	parent_dn = of_find_node_by_phandle(be32_to_cpu(parent_phandle));
	if (!parent_dn)
	return -ENOENT;

	dn = dlpar_configure_connector(drc_index, parent_dn);
	if (!dn) {
	of_node_put(parent_dn);
	return -ENOENT;
	}

	rc = dlpar_attach_node(dn, parent_dn);
	if (rc)
	dlpar_free_cc_nodes(dn);

	of_node_put(parent_dn);
	return rc;
	}

	static void prrn_update_node(__be32 phandle)
	{
	struct pseries_hp_errorlog hp_elog;
	struct device_node *dn;

	/*
	* If a node is found from a the given phandle, the phandle does not
	* represent the drc index of an LMB and we can ignore.
	*/
	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
	if (dn) {
	of_node_put(dn);
	return;
	}

	hp_elog.resource = PSERIES_HP_ELOG_RESOURCE_MEM;
	hp_elog.action = PSERIES_HP_ELOG_ACTION_READD;
	hp_elog.id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
	hp_elog._drc_u.drc_index = phandle;

	handle_dlpar_errorlog(&hp_elog);
	}

	int pseries_devicetree_update(s32 scope)
	{
	char *rtas_buf;
	__be32 *data;
	int update_nodes_token;
	int rc;

	update_nodes_token = rtas_token("ibm,update-nodes");
	if (update_nodes_token == RTAS_UNKNOWN_SERVICE)
	return -EINVAL;

	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
	if (!rtas_buf)
	return -ENOMEM;

	do {
	rc = mobility_rtas_call(update_nodes_token, rtas_buf, scope);
	if (rc && rc != 1)
	break;

	data = (__be32 *)rtas_buf + 4;
	while (be32_to_cpu(*data) & NODE_ACTION_MASK) {
	int i;
	u32 action = be32_to_cpu(*data) & NODE_ACTION_MASK;
	u32 node_count = be32_to_cpu(*data) & NODE_COUNT_MASK;

	data++;

	for (i = 0; i < node_count; i++) {
	__be32 phandle = *data++;
	__be32 drc_index;

	switch (action) {
	case DELETE_DT_NODE:
	delete_dt_node(phandle);
	break;
	case UPDATE_DT_NODE:
	update_dt_node(phandle, scope);

	if (scope == PRRN_SCOPE)
	prrn_update_node(phandle);

	break;
	case ADD_DT_NODE:
	drc_index = *data++;
	add_dt_node(phandle, drc_index);
	break;
	}

	cond_resched();
	}
	}

	cond_resched();
	} while (rc == 1);

	kfree(rtas_buf);
	return rc;
	}

	void post_mobility_fixup(void)
	{
	int rc;
	int activate_fw_token;

	activate_fw_token = rtas_token("ibm,activate-firmware");
	if (activate_fw_token == RTAS_UNKNOWN_SERVICE) {
	printk(KERN_ERR "Could not make post-mobility "
	"activate-fw call.\n");
	return;
	}

	do {
	rc = rtas_call(activate_fw_token, 0, 1, NULL);
	} while (rtas_busy_delay(rc));

	if (rc)
	printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);

	/*
	* We don't want CPUs to go online/offline while the device
	* tree is being updated.
	*/
	cpus_read_lock();

	/*
	* It's common for the destination firmware to replace cache
	* nodes. Release all of the cacheinfo hierarchy's references
	* before updating the device tree.
	*/
	cacheinfo_teardown();

	rc = pseries_devicetree_update(MIGRATION_SCOPE);
	if (rc)
	printk(KERN_ERR "Post-mobility device tree update "
	"failed: %d\n", rc);

	cacheinfo_rebuild();

	cpus_read_unlock();

	/* Possibly switch to a new RFI flush type */
	pseries_setup_rfi_flush();

	return;
	}

	static ssize_t migration_store(struct class *class,
	struct class_attribute attr, const char buf,
	size_t count)
	{
	u64 streamid;
	int rc;

	rc = kstrtou64(buf, 0, &streamid);
	if (rc)
	return rc;

	stop_topology_update();

	do {
	rc = rtas_ibm_suspend_me(streamid);
	if (rc == -EAGAIN)
	ssleep(1);
	} while (rc == -EAGAIN);

	if (rc)
	return rc;

	post_mobility_fixup();

	start_topology_update();

	return count;
	}

	/*
	* Used by drmgr to determine the kernel behavior of the migration interface.
	*
	* Version 1: Performs all PAPR requirements for migration including
	* firmware activation and device tree update.
	*/
	#define MIGRATION_API_VERSION 1

	static CLASS_ATTR_WO(migration);
	static CLASS_ATTR_STRING(api_version, 0444, __stringify(MIGRATION_API_VERSION));

	static int __init mobility_sysfs_init(void)
	{
	int rc;

	mobility_kobj = kobject_create_and_add("mobility", kernel_kobj);
	if (!mobility_kobj)
	return -ENOMEM;

	rc = sysfs_create_file(mobility_kobj, &class_attr_migration.attr);
	if (rc)
	pr_err("mobility: unable to create migration sysfs file (%d)\n", rc);

	rc = sysfs_create_file(mobility_kobj, &class_attr_api_version.attr.attr);
	if (rc)
	pr_err("mobility: unable to create api_version sysfs file (%d)\n", rc);

	return 0;
	}
	machine_device_initcall(pseries, mobility_sysfs_init);