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-rw-r--r--arch/powerpc/platforms/pseries/mobility.c434
1 files changed, 434 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c
new file mode 100644
index 000000000..f386a7bc3
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/mobility.c
@@ -0,0 +1,434 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Support for Partition Mobility/Migration
+ *
+ * Copyright (C) 2010 Nathan Fontenot
+ * Copyright (C) 2010 IBM Corporation
+ */
+
+
+#define pr_fmt(fmt) "mobility: " fmt
+
+#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(struct device_node *dn)
+{
+ struct device_node *pdn;
+ bool is_platfac;
+
+ pdn = of_get_parent(dn);
+ is_platfac = of_node_is_type(dn, "ibm,platform-facilities") ||
+ of_node_is_type(pdn, "ibm,platform-facilities");
+ of_node_put(pdn);
+
+ /*
+ * The drivers that bind to nodes in the platform-facilities
+ * hierarchy don't support node removal, and the removal directive
+ * from firmware is always followed by an add of an equivalent
+ * node. The capability (e.g. RNG, encryption, compression)
+ * represented by the node is never interrupted by the migration.
+ * So ignore changes to this part of the tree.
+ */
+ if (is_platfac) {
+ pr_notice("ignoring remove operation for %pOFfp\n", dn);
+ return 0;
+ }
+
+ pr_debug("removing node %pOFfp\n", dn);
+ dlpar_detach_node(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) {
+ pr_debug("updating node %pOF property %s\n", dn, name);
+ of_update_property(dn, new_prop);
+ *prop = NULL;
+ }
+
+ return 0;
+}
+
+static int update_dt_node(struct device_node *dn, s32 scope)
+{
+ struct update_props_workarea *upwa;
+ 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;
+
+ upwa = (struct update_props_workarea *)&rtas_buf[0];
+ upwa->phandle = cpu_to_be32(dn->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);
+
+ kfree(rtas_buf);
+ return 0;
+}
+
+static int add_dt_node(struct device_node *parent_dn, __be32 drc_index)
+{
+ struct device_node *dn;
+ int rc;
+
+ dn = dlpar_configure_connector(drc_index, parent_dn);
+ if (!dn)
+ return -ENOENT;
+
+ /*
+ * Since delete_dt_node() ignores this node type, this is the
+ * necessary counterpart. We also know that a platform-facilities
+ * node returned from dlpar_configure_connector() has children
+ * attached, and dlpar_attach_node() only adds the parent, leaking
+ * the children. So ignore these on the add side for now.
+ */
+ if (of_node_is_type(dn, "ibm,platform-facilities")) {
+ pr_notice("ignoring add operation for %pOF\n", dn);
+ dlpar_free_cc_nodes(dn);
+ return 0;
+ }
+
+ rc = dlpar_attach_node(dn, parent_dn);
+ if (rc)
+ dlpar_free_cc_nodes(dn);
+
+ pr_debug("added node %pOFfp\n", dn);
+
+ return rc;
+}
+
+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++) {
+ struct device_node *np;
+ __be32 phandle = *data++;
+ __be32 drc_index;
+
+ np = of_find_node_by_phandle(be32_to_cpu(phandle));
+ if (!np) {
+ pr_warn("Failed lookup: phandle 0x%x for action 0x%x\n",
+ be32_to_cpu(phandle), action);
+ continue;
+ }
+
+ switch (action) {
+ case DELETE_DT_NODE:
+ delete_dt_node(np);
+ break;
+ case UPDATE_DT_NODE:
+ update_dt_node(np, scope);
+ break;
+ case ADD_DT_NODE:
+ drc_index = *data++;
+ add_dt_node(np, drc_index);
+ break;
+ }
+
+ of_node_put(np);
+ 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 L1 flush type */
+ pseries_setup_security_mitigations();
+
+ /* Reinitialise system information for hv-24x7 */
+ read_24x7_sys_info();
+
+ 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;
+
+ do {
+ rc = rtas_ibm_suspend_me(streamid);
+ if (rc == -EAGAIN)
+ ssleep(1);
+ } while (rc == -EAGAIN);
+
+ if (rc)
+ return rc;
+
+ post_mobility_fixup();
+
+ 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("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("unable to create api_version sysfs file (%d)\n", rc);
+
+ return 0;
+}
+machine_device_initcall(pseries, mobility_sysfs_init);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-09 20:35:26 +0000