powerpc/pseries: Move CPU DLPAR into the kernel

index fe6320d..438fdbd 100644
@@ -20,7 +20,6 @@
 #include <linux/of.h>
 
 #include "of_helpers.h"
-#include "offline_states.h"
 #include "pseries.h"
 
 #include <asm/prom.h>

@@ -338,220 +337,6 @@ int dlpar_release_drc(u32 drc_index)
 	return 0;
 }
 
-#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
-
-static int dlpar_online_cpu(struct device_node *dn)
-{
-	int rc = 0;
-	unsigned int cpu;
-	int len, nthreads, i;
-	const __be32 *intserv;
-	u32 thread;
-
-	intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
-	if (!intserv)
-		return -EINVAL;
-
-	nthreads = len / sizeof(u32);
-
-	cpu_maps_update_begin();
-	for (i = 0; i < nthreads; i++) {
-		thread = be32_to_cpu(intserv[i]);
-		for_each_present_cpu(cpu) {
-			if (get_hard_smp_processor_id(cpu) != thread)
-				continue;
-			BUG_ON(get_cpu_current_state(cpu)
-					!= CPU_STATE_OFFLINE);
-			cpu_maps_update_done();
-			rc = device_online(get_cpu_device(cpu));
-			if (rc)
-				goto out;
-			cpu_maps_update_begin();
-
-			break;
-		}
-		if (cpu == num_possible_cpus())
-			printk(KERN_WARNING "Could not find cpu to online "
-			       "with physical id 0x%x\n", thread);
-	}
-	cpu_maps_update_done();
-
-out:
-	return rc;
-
-}
-
-static bool dlpar_cpu_exists(struct device_node *parent, u32 drc_index)
-{
-	struct device_node *child = NULL;
-	u32 my_drc_index;
-	bool found;
-	int rc;
-
-	/* Assume cpu doesn't exist */
-	found = false;
-
-	for_each_child_of_node(parent, child) {
-		rc = of_property_read_u32(child, "ibm,my-drc-index",
-					  &my_drc_index);
-		if (rc)
-			continue;
-
-		if (my_drc_index == drc_index) {
-			of_node_put(child);
-			found = true;
-			break;
-		}
-	}
-
-	return found;
-}
-
-static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
-{
-	struct device_node *dn, *parent;
-	u32 drc_index;
-	int rc;
-
-	rc = kstrtou32(buf, 0, &drc_index);
-	if (rc)
-		return -EINVAL;
-
-	parent = of_find_node_by_path("/cpus");
-	if (!parent)
-		return -ENODEV;
-
-	if (dlpar_cpu_exists(parent, drc_index)) {
-		of_node_put(parent);
-		printk(KERN_WARNING "CPU with drc index %x already exists\n",
-		       drc_index);
-		return -EINVAL;
-	}
-
-	rc = dlpar_acquire_drc(drc_index);
-	if (rc) {
-		of_node_put(parent);
-		return -EINVAL;
-	}
-
-	dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
-	of_node_put(parent);
-	if (!dn) {
-		dlpar_release_drc(drc_index);
-		return -EINVAL;
-	}
-
-	rc = dlpar_attach_node(dn);
-	if (rc) {
-		dlpar_release_drc(drc_index);
-		dlpar_free_cc_nodes(dn);
-		return rc;
-	}
-
-	rc = dlpar_online_cpu(dn);
-	if (rc)
-		return rc;
-
-	return count;
-}
-
-static int dlpar_offline_cpu(struct device_node *dn)
-{
-	int rc = 0;
-	unsigned int cpu;
-	int len, nthreads, i;
-	const __be32 *intserv;
-	u32 thread;
-
-	intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
-	if (!intserv)
-		return -EINVAL;
-
-	nthreads = len / sizeof(u32);
-
-	cpu_maps_update_begin();
-	for (i = 0; i < nthreads; i++) {
-		thread = be32_to_cpu(intserv[i]);
-		for_each_present_cpu(cpu) {
-			if (get_hard_smp_processor_id(cpu) != thread)
-				continue;
-
-			if (get_cpu_current_state(cpu) == CPU_STATE_OFFLINE)
-				break;
-
-			if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
-				set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
-				cpu_maps_update_done();
-				rc = device_offline(get_cpu_device(cpu));
-				if (rc)
-					goto out;
-				cpu_maps_update_begin();
-				break;
-
-			}
-
-			/*
-			 * The cpu is in CPU_STATE_INACTIVE.
-			 * Upgrade it's state to CPU_STATE_OFFLINE.
-			 */
-			set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
-			BUG_ON(plpar_hcall_norets(H_PROD, thread)
-								!= H_SUCCESS);
-			__cpu_die(cpu);
-			break;
-		}
-		if (cpu == num_possible_cpus())
-			printk(KERN_WARNING "Could not find cpu to offline "
-			       "with physical id 0x%x\n", thread);
-	}
-	cpu_maps_update_done();
-
-out:
-	return rc;
-
-}
-
-static ssize_t dlpar_cpu_release(const char *buf, size_t count)
-{
-	struct device_node *dn;
-	u32 drc_index;
-	int rc;
-
-	dn = of_find_node_by_path(buf);
-	if (!dn)
-		return -EINVAL;
-
-	rc = of_property_read_u32(dn, "ibm,my-drc-index", &drc_index);
-	if (rc) {
-		of_node_put(dn);
-		return -EINVAL;
-	}
-
-	rc = dlpar_offline_cpu(dn);
-	if (rc) {
-		of_node_put(dn);
-		return -EINVAL;
-	}
-
-	rc = dlpar_release_drc(drc_index);
-	if (rc) {
-		of_node_put(dn);
-		return rc;
-	}
-
-	rc = dlpar_detach_node(dn);
-	if (rc) {
-		dlpar_acquire_drc(drc_index);
-		return rc;
-	}
-
-	of_node_put(dn);
-
-	return count;
-}
-
-#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
-
 static int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
 {
 	int rc;

@@ -659,16 +444,7 @@ static CLASS_ATTR(dlpar, S_IWUSR, NULL, dlpar_store);
 
 static int __init pseries_dlpar_init(void)
 {
-	int rc;
-
-#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
-	ppc_md.cpu_probe = dlpar_cpu_probe;
-	ppc_md.cpu_release = dlpar_cpu_release;
-#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
-
-	rc = sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
-
-	return rc;
+	return sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
 }
 machine_device_initcall(pseries, pseries_dlpar_init);
 

236 lines not on this page · raw message

index 10c2942..d6cb184 100644
@@ -340,8 +340,6 @@ static void pseries_remove_processor(struct device_node *np)
 	cpu_maps_update_done();
 }
 
-#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
-
 static int dlpar_online_cpu(struct device_node *dn)
 {
 	int rc = 0;

@@ -409,16 +407,11 @@ static bool dlpar_cpu_exists(struct device_node *parent, u32 drc_index)
 	return found;
 }
 
-static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
+static ssize_t dlpar_cpu_add(u32 drc_index)
 {
 	struct device_node *dn, *parent;
-	u32 drc_index;
 	int rc;
 
-	rc = kstrtou32(buf, 0, &drc_index);
-	if (rc)
-		return -EINVAL;
-
 	parent = of_find_node_by_path("/cpus");
 	if (!parent)
 		return -ENODEV;

@@ -449,10 +442,7 @@ static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
 	}
 
 	rc = dlpar_online_cpu(dn);
-	if (rc)
-		return rc;
-
-	return count;
+	return rc;
 }
 
 static int dlpar_offline_cpu(struct device_node *dn)

@@ -511,6 +501,41 @@ out:
 
 }
 
+static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index)
+{
+	int rc;
+
+	rc = dlpar_offline_cpu(dn);
+	if (rc)
+		return -EINVAL;
+
+	rc = dlpar_release_drc(drc_index);
+	if (rc)
+		return rc;
+
+	rc = dlpar_detach_node(dn);
+	if (rc)
+		dlpar_acquire_drc(drc_index);
+
+	return rc;
+}
+
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
+
+static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
+{
+	u32 drc_index;
+	int rc;
+
+	rc = kstrtou32(buf, 0, &drc_index);
+	if (rc)
+		return -EINVAL;
+
+	rc = dlpar_cpu_add(drc_index);
+
+	return rc ? rc : count;
+}
+
 static ssize_t dlpar_cpu_release(const char *buf, size_t count)
 {
 	struct device_node *dn;

@@ -527,27 +552,10 @@ static ssize_t dlpar_cpu_release(const char *buf, size_t count)
 		return -EINVAL;
 	}
 
-	rc = dlpar_offline_cpu(dn);
-	if (rc) {
-		of_node_put(dn);
-		return -EINVAL;
-	}
-
-	rc = dlpar_release_drc(drc_index);
-	if (rc) {
-		of_node_put(dn);
-		return rc;
-	}
-
-	rc = dlpar_detach_node(dn);
-	if (rc) {
-		dlpar_acquire_drc(drc_index);
-		return rc;
-	}
-
+	rc = dlpar_cpu_remove(dn, drc_index);
 	of_node_put(dn);
 
-	return count;
+	return rc ? rc : count;
 }
 
 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */

index d6cb184..f080e81 100644
@@ -18,6 +18,8 @@
  *      2 of the License, or (at your option) any later version.
  */
 
+#define pr_fmt(fmt)     "pseries-hotplug-cpu: " fmt
+
 #include <linux/kernel.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>

@@ -410,38 +412,67 @@ static bool dlpar_cpu_exists(struct device_node *parent, u32 drc_index)
 static ssize_t dlpar_cpu_add(u32 drc_index)
 {
 	struct device_node *dn, *parent;
-	int rc;
+	int rc, saved_rc;
+
+	pr_debug("Attempting to add CPU, drc index: %x\n", drc_index);
 
 	parent = of_find_node_by_path("/cpus");
-	if (!parent)
+	if (!parent) {
+		pr_warn("Failed to find CPU root node \"/cpus\"\n");
 		return -ENODEV;
+	}
 
 	if (dlpar_cpu_exists(parent, drc_index)) {
 		of_node_put(parent);
-		printk(KERN_WARNING "CPU with drc index %x already exists\n",
-		       drc_index);
+		pr_warn("CPU with drc index %x already exists\n", drc_index);
 		return -EINVAL;
 	}
 
 	rc = dlpar_acquire_drc(drc_index);
 	if (rc) {
+		pr_warn("Failed to acquire DRC, rc: %d, drc index: %x\n",
+			rc, drc_index);
 		of_node_put(parent);
 		return -EINVAL;
 	}
 
 	dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
 	of_node_put(parent);
-	if (!dn)
+	if (!dn) {
+		pr_warn("Failed call to configure-connector, drc index: %x\n",
+			drc_index);
+		dlpar_release_drc(drc_index);
 		return -EINVAL;
+	}
 
 	rc = dlpar_attach_node(dn);
 	if (rc) {
-		dlpar_release_drc(drc_index);
-		dlpar_free_cc_nodes(dn);
-		return rc;
+		saved_rc = rc;
+		pr_warn("Failed to attach node %s, rc: %d, drc index: %x\n",
+			dn->name, rc, drc_index);
+
+		rc = dlpar_release_drc(drc_index);
+		if (!rc)
+			dlpar_free_cc_nodes(dn);
+
+		return saved_rc;
 	}
 
 	rc = dlpar_online_cpu(dn);
+	if (rc) {
+		saved_rc = rc;
+		pr_warn("Failed to online cpu %s, rc: %d, drc index: %x\n",
+			dn->name, rc, drc_index);
+
+		rc = dlpar_detach_node(dn);
+		if (!rc)
+			dlpar_release_drc(drc_index);
+
+		return saved_rc;
+	}
+
+	pr_debug("Successfully added CPU %s, drc index: %x\n", dn->name,
+		 drc_index);
 	return rc;
 }
 

@@ -505,19 +536,38 @@ static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index)
 {
 	int rc;
 
+	pr_debug("Attemping to remove CPU %s, drc index: %x\n",
+		 dn->name, drc_index);
+
 	rc = dlpar_offline_cpu(dn);
-	if (rc)
+	if (rc) {
+		pr_warn("Failed to offline CPU %s, rc: %d\n", dn->name, rc);
 		return -EINVAL;
+	}
 
 	rc = dlpar_release_drc(drc_index);
-	if (rc)
+	if (rc) {
+		pr_warn("Failed to release drc (%x) for CPU %s, rc: %d\n",
+			drc_index, dn->name, rc);
+		dlpar_online_cpu(dn);
 		return rc;
+	}
 
 	rc = dlpar_detach_node(dn);
-	if (rc)
-		dlpar_acquire_drc(drc_index);
+	if (rc) {
+		int saved_rc = rc;
 
-	return rc;
+		pr_warn("Failed to detach CPU %s, rc: %d", dn->name, rc);
+
+		rc = dlpar_acquire_drc(drc_index);
+		if (!rc)
+			dlpar_online_cpu(dn);
+
+		return saved_rc;
+	}
+
+	pr_debug("Successfully removed CPU, drc index: %x\n", drc_index);
+	return 0;
 }
 
 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE

index f080e81..635f0ba 100644
@@ -26,6 +26,7 @@
 #include <linux/sched.h>	/* for idle_task_exit */
 #include <linux/cpu.h>
 #include <linux/of.h>
+#include <linux/slab.h>
 #include <asm/prom.h>
 #include <asm/rtas.h>
 #include <asm/firmware.h>

@@ -570,6 +571,143 @@ static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index)
 	return 0;
 }
 
+static struct device_node *cpu_drc_index_to_dn(u32 drc_index)
+{
+	struct device_node *dn;
+	u32 my_index;
+	int rc;
+
+	for_each_node_by_type(dn, "cpu") {
+		rc = of_property_read_u32(dn, "ibm,my-drc-index", &my_index);
+		if (rc)
+			continue;
+
+		if (my_index == drc_index)
+			break;
+	}
+
+	return dn;
+}
+
+static int dlpar_cpu_remove_by_index(u32 drc_index)
+{
+	struct device_node *dn;
+	int rc;
+
+	dn = cpu_drc_index_to_dn(drc_index);
+	if (!dn)
+		return -ENODEV;
+
+	rc = dlpar_cpu_remove(dn, drc_index);
+	of_node_put(dn);
+	return rc;
+}
+
+static u32 *dlpar_cpus_to_remove(int cpus_to_remove)
+{
+	struct device_node *dn;
+	u32 *cpu_drcs;
+	int cpus_found = 0;
+	int i, rc;
+
+	cpu_drcs = kcalloc(cpus_to_remove, sizeof(*cpu_drcs), GFP_KERNEL);
+	if (!cpu_drcs)
+		return NULL;
+
+	i = 0;
+	for_each_node_by_type(dn, "cpu") {
+		cpus_found++;
+
+		if (cpus_found > cpus_to_remove) {
+			of_node_put(dn);
+			break;
+		}
+
+		rc = of_property_read_u32(dn, "ibm,my-drc-index",
+					  &cpu_drcs[i++]);
+		if (rc) {
+			of_node_put(dn);
+			break;
+		}
+	}
+
+	/* We want to find cpus_to_remove + 1 CPUs to ensure we do not
+	 * remove the last CPU.
+	 */
+	if (cpus_found <= cpus_to_remove) {
+		pr_warn("Failed to find enough CPUs (%d of %d) to remove\n",
+			cpus_found, cpus_to_remove);
+		kfree(cpu_drcs);
+		cpu_drcs = NULL;
+	}
+
+	return cpu_drcs;
+}
+
+static int dlpar_cpu_remove_by_count(u32 cpus_to_remove)
+{
+	u32 *cpu_drcs;
+	int cpus_removed = 0;
+	int i, rc;
+
+	pr_debug("Attempting to hot-remove %d CPUs\n", cpus_to_remove);
+
+	cpu_drcs = dlpar_cpus_to_remove(cpus_to_remove);
+	if (!cpu_drcs)
+		return -EINVAL;
+
+	for (i = 0; i < cpus_to_remove; i++) {
+		rc = dlpar_cpu_remove_by_index(cpu_drcs[i]);
+		if (rc)
+			break;
+
+		cpus_removed++;
+	}
+
+	if (cpus_removed != cpus_to_remove) {
+		pr_warn("CPU hot-remove failed, adding back removed CPUs\n");
+
+		for (i = 0; i < cpus_removed; i++)
+			dlpar_cpu_add(cpu_drcs[i]);
+
+		rc = -EINVAL;
+	} else {
+		rc = 0;
+	}
+
+	kfree(cpu_drcs);
+	return rc;
+}
+
+int dlpar_cpu(struct pseries_hp_errorlog *hp_elog)
+{
+	u32 count, drc_index;
+	int rc;
+
+	count = hp_elog->_drc_u.drc_count;
+	drc_index = hp_elog->_drc_u.drc_index;
+
+	lock_device_hotplug();
+
+	switch (hp_elog->action) {
+	case PSERIES_HP_ELOG_ACTION_REMOVE:
+		if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
+			rc = dlpar_cpu_remove_by_count(count);
+		else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
+			rc = dlpar_cpu_remove_by_index(drc_index);
+		else
+			rc = -EINVAL;
+		break;
+	default:
+		pr_err("Invalid action (%d) specified\n", hp_elog->action);
+		rc = -EINVAL;
+		break;
+	}
+
+	unlock_device_hotplug();
+	return rc;
+}
+
 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
 
 static ssize_t dlpar_cpu_probe(const char *buf, size_t count)

index 8411c27..7aa83f0 100644
@@ -73,6 +73,15 @@ static inline int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 }
 #endif
 
+#ifdef CONFIG_HOTPLUG_CPU
+int dlpar_cpu(struct pseries_hp_errorlog *hp_elog);
+#else
+static inline int dlpar_cpu(struct pseries_hp_errorlog *hp_elog)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
 /* PCI root bridge prepare function override for pseries */
 struct pci_host_bridge;
 int pseries_root_bridge_prepare(struct pci_host_bridge *bridge);

index 635f0ba..8ec52c0 100644
@@ -679,6 +679,92 @@ static int dlpar_cpu_remove_by_count(u32 cpus_to_remove)
 	return rc;
 }
 
+static u32 *dlpar_cpus_to_add(u32 cpus_to_add)
+{
+	struct device_node *parent;
+	u32 *cpu_drcs;
+	int cpus_found = 0;
+	int i, index, rc;
+
+	cpu_drcs = kcalloc(cpus_to_add, sizeof(*cpu_drcs), GFP_KERNEL);
+	if (!cpu_drcs)
+		return NULL;
+
+	parent = of_find_node_by_path("/cpus");
+	if (!parent) {
+		kfree(cpu_drcs);
+		return NULL;
+	}
+
+	/* Search the ibm,drc-indexes array for possible CPU drcs to
+	 * add. Note that the format of the ibm,drc-indexes array is
+	 * the number of entries in the array followed by the array
+	 * of drc values so we start looking at index = 1.
+	 */
+	i = 0;
+	index = 1;
+	while (cpus_found < cpus_to_add) {
+		u32 drc;
+
+		rc = of_property_read_u32_index(parent, "ibm,drc-indexes",
+						index++, &drc);
+		if (rc)
+			break;
+
+		if (dlpar_cpu_exists(parent, drc))
+			continue;
+
+		cpu_drcs[i++] = drc;
+		cpus_found++;
+	}
+
+	of_node_put(parent);
+
+	if (cpus_found < cpus_to_add) {
+		pr_warn("Failed to find enough CPUs (%d of %d) to add\n",
+			cpus_found, cpus_to_add);
+		kfree(cpu_drcs);
+		cpu_drcs = NULL;
+	}
+
+	return cpu_drcs;
+}
+
+static int dlpar_cpu_add_by_count(u32 cpus_to_add)
+{
+	u32 *cpu_drcs;
+	int cpus_added = 0;
+	int i, rc;
+
+	pr_debug("Attempting to hot-add %d CPUs\n", cpus_to_add);
+
+	cpu_drcs = dlpar_cpus_to_add(cpus_to_add);
+	if (!cpu_drcs)
+		return -EINVAL;
+
+	for (i = 0; i < cpus_to_add; i++) {
+		rc = dlpar_cpu_add(cpu_drcs[i]);
+		if (rc)
+			break;
+
+		cpus_added++;
+	}
+
+	if (cpus_added < cpus_to_add) {
+		pr_warn("CPU hot-add failed, removing any added CPUs\n");
+
+		for (i = 0; i < cpus_added; i++)
+			dlpar_cpu_remove_by_index(cpu_drcs[i]);
+
+		rc = -EINVAL;
+	} else {
+		rc = 0;
+	}
+
+	kfree(cpu_drcs);
+	return rc;
+}
+
 int dlpar_cpu(struct pseries_hp_errorlog *hp_elog)
 {
 	u32 count, drc_index;

@@ -698,6 +784,14 @@ int dlpar_cpu(struct pseries_hp_errorlog *hp_elog)
 		else
 			rc = -EINVAL;
 		break;
+	case PSERIES_HP_ELOG_ACTION_ADD:
+		if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
+			rc = dlpar_cpu_add_by_count(count);
+		else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
+			rc = dlpar_cpu_add(drc_index);
+		else
+			rc = -EINVAL;
+		break;
 	default:
 		pr_err("Invalid action (%d) specified\n", hp_elog->action);
 		rc = -EINVAL;

index 438fdbd..2b93ae8 100644
@@ -356,6 +356,9 @@ static int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
 	case PSERIES_HP_ELOG_RESOURCE_MEM:
 		rc = dlpar_memory(hp_elog);
 		break;
+	case PSERIES_HP_ELOG_RESOURCE_CPU:
+		rc = dlpar_cpu(hp_elog);
+		break;
 	default:
 		pr_warn_ratelimited("Invalid resource (%d) specified\n",
 				    hp_elog->resource);

@@ -385,6 +388,9 @@ static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
 	if (!strncmp(arg, "memory", 6)) {
 		hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_MEM;
 		arg += strlen("memory ");
+	} else if (!strncmp(arg, "cpu", 3)) {
+		hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_CPU;
+		arg += strlen("cpu ");
 	} else {
 		pr_err("Invalid resource specified: \"%s\"\n", buf);
 		rc = -EINVAL;