[PATCH 0/3] Kernel handling of Dynamic Logical Partitioning

[PATCH 0/3] Kernel handling of Dynamic Logical Partitioning

[Nathan Fontenot]

The Dynamic Logical Partitioning (DLPAR) capabilities of the powerpc pseries
platform allows for the addition and removal of resources (i.e. cpus,
memory, pci devices) from a partition. The removal of a resource involves
removing the resource's node from the device tree and then returning the
resource to firmware via the rtas set-indicator call.  To add a resource, it
is first obtained from firmware via the rtas set-indicator call and then a
new device tree node is created using the ibm,configure-coinnector rtas call
and added to the device tree.

The following set of patches implements the needed infrastructure to have the
kernel handle the DLPAR addition and removal of cpus (other DLPAR'able items 
to follow in future patches).  The framework for this is to create a set of 
probe/release sysfs files that will facilitate arch-specific call-outs to 
handle addition and removal of cpus to the system.

-Nathan Fontenot

1/3 - powerpc/pseries kernel DLPAR infrastructure
2/3 - Create probe/release sysfs files and the powerpc handlers
3/3 - powerpc/pseries CPU DLPAR handling

 arch/powerpc/Kconfig                        |    4 
 arch/powerpc/include/asm/machdep.h          |    5 
 arch/powerpc/include/asm/pSeries_reconfig.h |    1 
 arch/powerpc/kernel/sysfs.c                 |   19 +
 arch/powerpc/platforms/pseries/Makefile     |    2 
 arch/powerpc/platforms/pseries/dlpar.c      |  412 ++++++++++++++++++++++++++++
 arch/powerpc/platforms/pseries/reconfig.c   |    2 
 drivers/base/cpu.c                          |   32 ++
 include/linux/cpu.h                         |    4 
 9 files changed, 479 insertions(+), 2 deletions(-)

[PATCH 1/3] Kernel DLPAR infrastructure

[Nathan Fontenot]

This patch provides the kernel DLPAR infrastructure in a new filed named
dlpar.c.  The functionality provided is for acquiring and releasing a resource
from firmware and the parsing of information returned from the
ibm,configure-connector rtas call.  Additionally this exports the pSeries
reconfiguration notifier chain so that it can be invoked when device tree 
updates are made.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com> 
---

---
 arch/powerpc/include/asm/pSeries_reconfig.h |    1 
 arch/powerpc/platforms/pseries/Makefile     |    2 
 arch/powerpc/platforms/pseries/dlpar.c      |  324 ++++++++++++++++++++++++++++
 arch/powerpc/platforms/pseries/reconfig.c   |    2 
 4 files changed, 327 insertions(+), 2 deletions(-)

Index: powerpc/arch/powerpc/platforms/pseries/dlpar.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ powerpc/arch/powerpc/platforms/pseries/dlpar.c	2009-11-24 23:31:28.000000000 -0600
@@ -0,0 +1,324 @@
+/*
+ * Support for dynamic reconfiguration for PCI, Memory, and CPU
+ * Hotplug and Dynamic Logical Partitioning on RPA platforms.
+ *
+ * Copyright (C) 2009 Nathan Fontenot
+ * Copyright (C) 2009 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/notifier.h>
+#include <linux/proc_fs.h>
+#include <linux/spinlock.h>
+#include <linux/cpu.h>
+
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/uaccess.h>
+#include <asm/rtas.h>
+#include <asm/pSeries_reconfig.h>
+
+struct cc_workarea {
+	u32	drc_index;
+	u32	zero;
+	u32	name_offset;
+	u32	prop_length;
+	u32	prop_offset;
+};
+
+static void dlpar_free_cc_property(struct property *prop)
+{
+	kfree(prop->name);
+	kfree(prop->value);
+	kfree(prop);
+}
+
+static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
+{
+	struct property *prop;
+	char *name;
+	char *value;
+
+	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+	if (!prop)
+		return NULL;
+
+	name = (char *)ccwa + ccwa->name_offset;
+	prop->name = kstrdup(name, GFP_KERNEL);
+
+	prop->length = ccwa->prop_length;
+	value = (char *)ccwa + ccwa->prop_offset;
+	prop->value = kzalloc(prop->length, GFP_KERNEL);
+	if (!prop->value) {
+		dlpar_free_cc_property(prop);
+		return NULL;
+	}
+
+	memcpy(prop->value, value, prop->length);
+	return prop;
+}
+
+static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa)
+{
+	struct device_node *dn;
+	char *name;
+
+	dn = kzalloc(sizeof(*dn), GFP_KERNEL);
+	if (!dn)
+		return NULL;
+
+	name = (char *)ccwa + ccwa->name_offset;
+	dn->full_name = kstrdup(name, GFP_KERNEL);
+
+	return dn;
+}
+
+static void dlpar_free_one_cc_node(struct device_node *dn)
+{
+	struct property *prop;
+
+	while (dn->properties) {
+		prop = dn->properties;
+		dn->properties = prop->next;
+		dlpar_free_cc_property(prop);
+	}
+
+	kfree(dn->full_name);
+	kfree(dn);
+}
+
+static void dlpar_free_cc_nodes(struct device_node *dn)
+{
+	if (dn->child)
+		dlpar_free_cc_nodes(dn->child);
+
+	if (dn->sibling)
+		dlpar_free_cc_nodes(dn->sibling);
+
+	dlpar_free_one_cc_node(dn);
+}
+
+#define NEXT_SIBLING    1
+#define NEXT_CHILD      2
+#define NEXT_PROPERTY   3
+#define PREV_PARENT     4
+#define MORE_MEMORY     5
+#define CALL_AGAIN	-2
+#define ERR_CFG_USE     -9003
+
+struct device_node *dlpar_configure_connector(u32 drc_index)
+{
+	struct device_node *dn;
+	struct device_node *first_dn = NULL;
+	struct device_node *last_dn = NULL;
+	struct property *property;
+	struct property *last_property = NULL;
+	struct cc_workarea *ccwa;
+	int cc_token;
+	int rc;
+
+	cc_token = rtas_token("ibm,configure-connector");
+	if (cc_token == RTAS_UNKNOWN_SERVICE)
+		return NULL;
+
+	spin_lock(&rtas_data_buf_lock);
+	ccwa = (struct cc_workarea *)&rtas_data_buf[0];
+	ccwa->drc_index = drc_index;
+	ccwa->zero = 0;
+
+	rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
+	while (rc) {
+		switch (rc) {
+		case NEXT_SIBLING:
+			dn = dlpar_parse_cc_node(ccwa);
+			if (!dn)
+				goto cc_error;
+
+			dn->parent = last_dn->parent;
+			last_dn->sibling = dn;
+			last_dn = dn;
+			break;
+
+		case NEXT_CHILD:
+			dn = dlpar_parse_cc_node(ccwa);
+			if (!dn)
+				goto cc_error;
+
+			if (!first_dn)
+				first_dn = dn;
+			else {
+				dn->parent = last_dn;
+				if (last_dn)
+					last_dn->child = dn;
+			}
+
+			last_dn = dn;
+			break;
+
+		case NEXT_PROPERTY:
+			property = dlpar_parse_cc_property(ccwa);
+			if (!property)
+				goto cc_error;
+
+			if (!last_dn->properties)
+				last_dn->properties = property;
+			else
+				last_property->next = property;
+
+			last_property = property;
+			break;
+
+		case PREV_PARENT:
+			last_dn = last_dn->parent;
+			break;
+
+		case CALL_AGAIN:
+			break;
+
+		case MORE_MEMORY:
+		case ERR_CFG_USE:
+		default:
+			printk(KERN_ERR "Unexpected Error (%d) "
+			       "returned from configure-connector\n", rc);
+			goto cc_error;
+		}
+
+		rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
+	}
+
+	spin_unlock(&rtas_data_buf_lock);
+	return first_dn;
+
+cc_error:
+	if (first_dn)
+		dlpar_free_cc_nodes(first_dn);
+	spin_unlock(&rtas_data_buf_lock);
+	return NULL;
+}
+
+static struct device_node *derive_parent(const char *path)
+{
+	struct device_node *parent;
+	char parent_path[128];
+	int parent_path_len;
+
+	parent_path_len = strrchr(path, '/') - path + 1;
+	strlcpy(parent_path, path, parent_path_len);
+
+	parent = of_find_node_by_path(parent_path);
+
+	return parent;
+}
+
+int dlpar_attach_node(struct device_node *dn)
+{
+	struct proc_dir_entry *ent;
+	int rc;
+
+	of_node_set_flag(dn, OF_DYNAMIC);
+	kref_init(&dn->kref);
+	dn->parent = derive_parent(dn->full_name);
+
+	rc = blocking_notifier_call_chain(&pSeries_reconfig_chain,
+					  PSERIES_RECONFIG_ADD, dn);
+	if (rc == NOTIFY_BAD) {
+		printk(KERN_ERR "Failed to add device node %s\n",
+		       dn->full_name);
+		return -ENOMEM; /* For now, safe to assume kmalloc failure */
+	}
+
+	of_attach_node(dn);
+
+#ifdef CONFIG_PROC_DEVICETREE
+	ent = proc_mkdir(strrchr(dn->full_name, '/') + 1, dn->parent->pde);
+	if (ent)
+		proc_device_tree_add_node(dn, ent);
+#endif
+
+	of_node_put(dn->parent);
+	return 0;
+}
+
+int dlpar_detach_node(struct device_node *dn)
+{
+	struct device_node *parent = dn->parent;
+	struct property *prop = dn->properties;
+
+#ifdef CONFIG_PROC_DEVICETREE
+	while (prop) {
+		remove_proc_entry(prop->name, dn->pde);
+		prop = prop->next;
+	}
+
+	if (dn->pde)
+		remove_proc_entry(dn->pde->name, parent->pde);
+#endif
+
+	blocking_notifier_call_chain(&pSeries_reconfig_chain,
+			    PSERIES_RECONFIG_REMOVE, dn);
+	of_detach_node(dn);
+	of_node_put(dn); /* Must decrement the refcount */
+
+	return 0;
+}
+
+#define DR_ENTITY_SENSE		9003
+#define DR_ENTITY_PRESENT	1
+#define DR_ENTITY_UNUSABLE	2
+#define ALLOCATION_STATE	9003
+#define ALLOC_UNUSABLE		0
+#define ALLOC_USABLE		1
+#define ISOLATION_STATE		9001
+#define ISOLATE			0
+#define UNISOLATE		1
+
+int dlpar_acquire_drc(u32 drc_index)
+{
+	int dr_status, rc;
+
+	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
+		       DR_ENTITY_SENSE, drc_index);
+	if (rc || dr_status != DR_ENTITY_UNUSABLE)
+		return -1;
+
+	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
+	if (rc)
+		return rc;
+
+	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
+	if (rc) {
+		rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
+		return rc;
+	}
+
+	return 0;
+}
+
+int dlpar_release_drc(u32 drc_index)
+{
+	int dr_status, rc;
+
+	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
+		       DR_ENTITY_SENSE, drc_index);
+	if (rc || dr_status != DR_ENTITY_PRESENT)
+		return -1;
+
+	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
+	if (rc)
+		return rc;
+
+	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
+	if (rc) {
+		rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
+		return rc;
+	}
+
+	return 0;
+}
+
+
Index: powerpc/arch/powerpc/platforms/pseries/Makefile
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/Makefile	2009-11-20 17:53:54.000000000 -0600
+++ powerpc/arch/powerpc/platforms/pseries/Makefile	2009-11-20 17:55:52.000000000 -0600
@@ -8,7 +8,7 @@
 
 obj-y			:= lpar.o hvCall.o nvram.o reconfig.o \
 			   setup.o iommu.o ras.o rtasd.o \
-			   firmware.o power.o
+			   firmware.o power.o dlpar.o
 obj-$(CONFIG_SMP)	+= smp.o
 obj-$(CONFIG_XICS)	+= xics.o
 obj-$(CONFIG_SCANLOG)	+= scanlog.o
Index: powerpc/arch/powerpc/include/asm/pSeries_reconfig.h
===================================================================
--- powerpc.orig/arch/powerpc/include/asm/pSeries_reconfig.h	2009-11-20 17:53:54.000000000 -0600
+++ powerpc/arch/powerpc/include/asm/pSeries_reconfig.h	2009-11-20 17:55:52.000000000 -0600
@@ -17,6 +17,7 @@
 #ifdef CONFIG_PPC_PSERIES
 extern int pSeries_reconfig_notifier_register(struct notifier_block *);
 extern void pSeries_reconfig_notifier_unregister(struct notifier_block *);
+extern struct blocking_notifier_head pSeries_reconfig_chain;
 #else /* !CONFIG_PPC_PSERIES */
 static inline int pSeries_reconfig_notifier_register(struct notifier_block *nb)
 {
Index: powerpc/arch/powerpc/platforms/pseries/reconfig.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/reconfig.c	2009-11-20 17:53:54.000000000 -0600
+++ powerpc/arch/powerpc/platforms/pseries/reconfig.c	2009-11-20 17:55:52.000000000 -0600
@@ -96,7 +96,7 @@
 	return parent;
 }
 
-static BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
+BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
 
 int pSeries_reconfig_notifier_register(struct notifier_block *nb)
 {

[PATCH 2/3] sysfs cpu probe/release files

[Nathan Fontenot]

Create new probe and release sysfs files to facilitate adding and removing
cpus from the system.  This also creates the powerpc specific stubs to handle
the arch callouts from writes to the sysfs files.

The creation and use of these files is regulated by the 
CONFIG_ARCH_CPU_PROBE_RELEASE option so that only architectures that need the
capability will have the files created.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
---
 arch/powerpc/Kconfig               |    4 ++++
 arch/powerpc/include/asm/machdep.h |    5 +++++
 arch/powerpc/kernel/sysfs.c        |   19 +++++++++++++++++++
 drivers/base/cpu.c                 |   32 ++++++++++++++++++++++++++++++++
 include/linux/cpu.h                |    4 ++++
 5 files changed, 64 insertions(+)

Index: powerpc/drivers/base/cpu.c
===================================================================
--- powerpc.orig/drivers/base/cpu.c	2009-11-23 18:19:23.000000000 -0600
+++ powerpc/drivers/base/cpu.c	2009-11-24 14:30:07.000000000 -0600
@@ -72,6 +72,38 @@
 	per_cpu(cpu_sys_devices, logical_cpu) = NULL;
 	return;
 }
+
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
+static ssize_t cpu_probe_store(struct class *class, const char *buf,
+			       size_t count)
+{
+	return arch_cpu_probe(buf, count);
+}
+
+static ssize_t cpu_release_store(struct class *class, const char *buf,
+				 size_t count)
+{
+	return arch_cpu_release(buf, count);
+}
+
+static CLASS_ATTR(probe, S_IWUSR, NULL, cpu_probe_store);
+static CLASS_ATTR(release, S_IWUSR, NULL, cpu_release_store);
+
+int __init cpu_probe_release_init(void)
+{
+	int rc;
+
+	rc = sysfs_create_file(&cpu_sysdev_class.kset.kobj,
+			       &class_attr_probe.attr);
+	if (!rc)
+		rc = sysfs_create_file(&cpu_sysdev_class.kset.kobj,
+				       &class_attr_release.attr);
+
+	return rc;
+}
+device_initcall(cpu_probe_release_init);
+#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
+
 #else /* ... !CONFIG_HOTPLUG_CPU */
 static inline void register_cpu_control(struct cpu *cpu)
 {
Index: powerpc/arch/powerpc/include/asm/machdep.h
===================================================================
--- powerpc.orig/arch/powerpc/include/asm/machdep.h	2009-11-23 18:19:23.000000000 -0600
+++ powerpc/arch/powerpc/include/asm/machdep.h	2009-11-24 14:30:07.000000000 -0600
@@ -266,6 +266,11 @@
 	void (*suspend_disable_irqs)(void);
 	void (*suspend_enable_irqs)(void);
 #endif
+
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
+	ssize_t (*cpu_probe)(const char *, size_t);
+	ssize_t (*cpu_release)(const char *, size_t);
+#endif
 };
 
 extern void e500_idle(void);
Index: powerpc/arch/powerpc/kernel/sysfs.c
===================================================================
--- powerpc.orig/arch/powerpc/kernel/sysfs.c	2009-11-23 18:19:23.000000000 -0600
+++ powerpc/arch/powerpc/kernel/sysfs.c	2009-11-24 14:43:40.000000000 -0600
@@ -461,6 +461,25 @@
 
 	cacheinfo_cpu_offline(cpu);
 }
+
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
+ssize_t arch_cpu_probe(const char *buf, size_t count)
+{
+	if (ppc_md.cpu_probe)
+		return ppc_md.cpu_probe(buf, count);
+
+	return -EINVAL;
+}
+
+ssize_t arch_cpu_release(const char *buf, size_t count)
+{
+	if (ppc_md.cpu_release)
+		return ppc_md.cpu_release(buf, count);
+
+	return -EINVAL;
+}
+#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
+
 #endif /* CONFIG_HOTPLUG_CPU */
 
 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
Index: powerpc/arch/powerpc/Kconfig
===================================================================
--- powerpc.orig/arch/powerpc/Kconfig	2009-11-23 18:19:23.000000000 -0600
+++ powerpc/arch/powerpc/Kconfig	2009-11-24 14:30:07.000000000 -0600
@@ -320,6 +320,10 @@
 
 	  Say N if you are unsure.
 
+config ARCH_CPU_PROBE_RELEASE
+	def_bool y
+	depends on HOTPLUG_CPU
+
 config ARCH_ENABLE_MEMORY_HOTPLUG
 	def_bool y
 
Index: powerpc/include/linux/cpu.h
===================================================================
--- powerpc.orig/include/linux/cpu.h	2009-11-23 18:19:23.000000000 -0600
+++ powerpc/include/linux/cpu.h	2009-11-24 14:30:07.000000000 -0600
@@ -43,6 +43,10 @@
 
 #ifdef CONFIG_HOTPLUG_CPU
 extern void unregister_cpu(struct cpu *cpu);
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
+extern ssize_t arch_cpu_probe(const char *, size_t);
+extern ssize_t arch_cpu_release(const char *, size_t);
+#endif
 #endif
 struct notifier_block;
 

[PATCH 3/3] CPU DLPAR handling

[Nathan Fontenot]

Register the pseries specific handlers for the powerpc architecture handlers
for the cpu probe and release files.  This also implements the cpu DLPAR
addition and removal of CPUS from the system.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
---

arch/powerpc/platforms/pseries/dlpar.c |   88 +++++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)

Index: powerpc/arch/powerpc/platforms/pseries/dlpar.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/dlpar.c	2009-11-24 23:29:12.000000000 -0600
+++ powerpc/arch/powerpc/platforms/pseries/dlpar.c	2009-11-24 23:29:24.000000000 -0600
@@ -321,4 +321,92 @@
 	return 0;
 }
 
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
 
+static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
+{
+	struct device_node *dn;
+	unsigned long drc_index;
+	char *cpu_name;
+	int rc;
+
+	rc = strict_strtoul(buf, 0, &drc_index);
+	if (rc)
+		return -EINVAL;
+
+	dn = dlpar_configure_connector(drc_index);
+	if (!dn)
+		return -EINVAL;
+
+	/* configure-connector reports cpus as living in the base
+	 * directory of the device tree.  CPUs actually live in the
+	 * cpus directory so we need to fixup the full_name.
+	 */
+	cpu_name = kzalloc(strlen(dn->full_name) + strlen("/cpus/") + 1,
+			   GFP_KERNEL);
+	if (!cpu_name) {
+		dlpar_free_cc_nodes(dn);
+		return -ENOMEM;
+	}
+
+	sprintf(cpu_name, "/cpus/%s", dn->full_name);
+	kfree(dn->full_name);
+	dn->full_name = cpu_name;
+
+	rc = dlpar_acquire_drc(drc_index);
+	if (rc) {
+		dlpar_free_cc_nodes(dn);
+		return -EINVAL;
+	}
+
+	rc = dlpar_attach_node(dn);
+	if (rc) {
+		dlpar_release_drc(drc_index);
+		dlpar_free_cc_nodes(dn);
+	}
+
+	return rc ? rc : count;
+}
+
+static ssize_t dlpar_cpu_release(const char *buf, size_t count)
+{
+	struct device_node *dn;
+	const u32 *drc_index;
+	int rc;
+
+	dn = of_find_node_by_path(buf);
+	if (!dn)
+		return -EINVAL;
+
+	drc_index = of_get_property(dn, "ibm,my-drc-index", NULL);
+	if (!drc_index) {
+		of_node_put(dn);
+		return -EINVAL;
+	}
+
+	rc = dlpar_release_drc(*drc_index);
+	if (rc) {
+		of_node_put(dn);
+		return -EINVAL;
+	}
+
+	rc = dlpar_detach_node(dn);
+	if (rc) {
+		dlpar_acquire_drc(*drc_index);
+		return rc;
+	}
+
+	of_node_put(dn);
+	return count;
+}
+
+static int __init pseries_dlpar_init(void)
+{
+	ppc_md.cpu_probe = dlpar_cpu_probe;
+	ppc_md.cpu_release = dlpar_cpu_release;
+
+	return 0;
+}
+machine_device_initcall(pseries, pseries_dlpar_init);
+
+#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */

Re: [PATCH 1/3] Kernel DLPAR infrastructure

[Michael Neuling]

In message <4B0C8CE3.4010207@austin.ibm.com> you wrote:
> This patch provides the kernel DLPAR infrastructure in a new filed named
> dlpar.c.  The functionality provided is for acquiring and releasing a resourc
e
> from firmware and the parsing of information returned from the
> ibm,configure-connector rtas call.  Additionally this exports the pSeries
> reconfiguration notifier chain so that it can be invoked when device tree 
> updates are made.
> 
> Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com> 

These look like they got white space munged somewhere...

Mikey

> ---
> 
> ---
>  arch/powerpc/include/asm/pSeries_reconfig.h |    1 
>  arch/powerpc/platforms/pseries/Makefile     |    2 
>  arch/powerpc/platforms/pseries/dlpar.c      |  324 +++++++++++++++++++++++++
+++
>  arch/powerpc/platforms/pseries/reconfig.c   |    2 
>  4 files changed, 327 insertions(+), 2 deletions(-)
> 
> Index: powerpc/arch/powerpc/platforms/pseries/dlpar.c
> ===================================================================
> --- /dev/null	1970-01-01 00:00:00.000000000 +0000
> +++ powerpc/arch/powerpc/platforms/pseries/dlpar.c	2009-11-24 23:31:28.000
000000 -0600
> @@ -0,0 +1,324 @@
> +/*
> + * Support for dynamic reconfiguration for PCI, Memory, and CPU
> + * Hotplug and Dynamic Logical Partitioning on RPA platforms.
> + *
> + * Copyright (C) 2009 Nathan Fontenot
> + * Copyright (C) 2009 IBM Corporation
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License version
> + * 2 as published by the Free Software Foundation.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/kref.h>
> +#include <linux/notifier.h>
> +#include <linux/proc_fs.h>
> +#include <linux/spinlock.h>
> +#include <linux/cpu.h>
> +
> +#include <asm/prom.h>
> +#include <asm/machdep.h>
> +#include <asm/uaccess.h>
> +#include <asm/rtas.h>
> +#include <asm/pSeries_reconfig.h>
> +
> +struct cc_workarea {
> +	u32	drc_index;
> +	u32	zero;
> +	u32	name_offset;
> +	u32	prop_length;
> +	u32	prop_offset;
> +};
> +
> +static void dlpar_free_cc_property(struct property *prop)
> +{
> +	kfree(prop->name);
> +	kfree(prop->value);
> +	kfree(prop);
> +}
> +
> +static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
> +{
> +	struct property *prop;
> +	char *name;
> +	char *value;
> +
> +	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
> +	if (!prop)
> +		return NULL;
> +
> +	name = (char *)ccwa + ccwa->name_offset;
> +	prop->name = kstrdup(name, GFP_KERNEL);
> +
> +	prop->length = ccwa->prop_length;
> +	value = (char *)ccwa + ccwa->prop_offset;
> +	prop->value = kzalloc(prop->length, GFP_KERNEL);
> +	if (!prop->value) {
> +		dlpar_free_cc_property(prop);
> +		return NULL;
> +	}
> +
> +	memcpy(prop->value, value, prop->length);
> +	return prop;
> +}
> +
> +static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa)
> +{
> +	struct device_node *dn;
> +	char *name;
> +
> +	dn = kzalloc(sizeof(*dn), GFP_KERNEL);
> +	if (!dn)
> +		return NULL;
> +
> +	name = (char *)ccwa + ccwa->name_offset;
> +	dn->full_name = kstrdup(name, GFP_KERNEL);
> +
> +	return dn;
> +}
> +
> +static void dlpar_free_one_cc_node(struct device_node *dn)
> +{
> +	struct property *prop;
> +
> +	while (dn->properties) {
> +		prop = dn->properties;
> +		dn->properties = prop->next;
> +		dlpar_free_cc_property(prop);
> +	}
> +
> +	kfree(dn->full_name);
> +	kfree(dn);
> +}
> +
> +static void dlpar_free_cc_nodes(struct device_node *dn)
> +{
> +	if (dn->child)
> +		dlpar_free_cc_nodes(dn->child);
> +
> +	if (dn->sibling)
> +		dlpar_free_cc_nodes(dn->sibling);
> +
> +	dlpar_free_one_cc_node(dn);
> +}
> +
> +#define NEXT_SIBLING    1
> +#define NEXT_CHILD      2
> +#define NEXT_PROPERTY   3
> +#define PREV_PARENT     4
> +#define MORE_MEMORY     5
> +#define CALL_AGAIN	-2
> +#define ERR_CFG_USE     -9003
> +
> +struct device_node *dlpar_configure_connector(u32 drc_index)
> +{
> +	struct device_node *dn;
> +	struct device_node *first_dn = NULL;
> +	struct device_node *last_dn = NULL;
> +	struct property *property;
> +	struct property *last_property = NULL;
> +	struct cc_workarea *ccwa;
> +	int cc_token;
> +	int rc;
> +
> +	cc_token = rtas_token("ibm,configure-connector");
> +	if (cc_token == RTAS_UNKNOWN_SERVICE)
> +		return NULL;
> +
> +	spin_lock(&rtas_data_buf_lock);
> +	ccwa = (struct cc_workarea *)&rtas_data_buf[0];
> +	ccwa->drc_index = drc_index;
> +	ccwa->zero = 0;
> +
> +	rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
> +	while (rc) {
> +		switch (rc) {
> +		case NEXT_SIBLING:
> +			dn = dlpar_parse_cc_node(ccwa);
> +			if (!dn)
> +				goto cc_error;
> +
> +			dn->parent = last_dn->parent;
> +			last_dn->sibling = dn;
> +			last_dn = dn;
> +			break;
> +
> +		case NEXT_CHILD:
> +			dn = dlpar_parse_cc_node(ccwa);
> +			if (!dn)
> +				goto cc_error;
> +
> +			if (!first_dn)
> +				first_dn = dn;
> +			else {
> +				dn->parent = last_dn;
> +				if (last_dn)
> +					last_dn->child = dn;
> +			}
> +
> +			last_dn = dn;
> +			break;
> +
> +		case NEXT_PROPERTY:
> +			property = dlpar_parse_cc_property(ccwa);
> +			if (!property)
> +				goto cc_error;
> +
> +			if (!last_dn->properties)
> +				last_dn->properties = property;
> +			else
> +				last_property->next = property;
> +
> +			last_property = property;
> +			break;
> +
> +		case PREV_PARENT:
> +			last_dn = last_dn->parent;
> +			break;
> +
> +		case CALL_AGAIN:
> +			break;
> +
> +		case MORE_MEMORY:
> +		case ERR_CFG_USE:
> +		default:
> +			printk(KERN_ERR "Unexpected Error (%d) "
> +			       "returned from configure-connector\n", rc);
> +			goto cc_error;
> +		}
> +
> +		rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
> +	}
> +
> +	spin_unlock(&rtas_data_buf_lock);
> +	return first_dn;
> +
> +cc_error:
> +	if (first_dn)
> +		dlpar_free_cc_nodes(first_dn);
> +	spin_unlock(&rtas_data_buf_lock);
> +	return NULL;
> +}
> +
> +static struct device_node *derive_parent(const char *path)
> +{
> +	struct device_node *parent;
> +	char parent_path[128];
> +	int parent_path_len;
> +
> +	parent_path_len = strrchr(path, '/') - path + 1;
> +	strlcpy(parent_path, path, parent_path_len);
> +
> +	parent = of_find_node_by_path(parent_path);
> +
> +	return parent;
> +}
> +
> +int dlpar_attach_node(struct device_node *dn)
> +{
> +	struct proc_dir_entry *ent;
> +	int rc;
> +
> +	of_node_set_flag(dn, OF_DYNAMIC);
> +	kref_init(&dn->kref);
> +	dn->parent = derive_parent(dn->full_name);
> +
> +	rc = blocking_notifier_call_chain(&pSeries_reconfig_chain,
> +					  PSERIES_RECONFIG_ADD, dn);
> +	if (rc == NOTIFY_BAD) {
> +		printk(KERN_ERR "Failed to add device node %s\n",
> +		       dn->full_name);
> +		return -ENOMEM; /* For now, safe to assume kmalloc failure */
> +	}
> +
> +	of_attach_node(dn);
> +
> +#ifdef CONFIG_PROC_DEVICETREE
> +	ent = proc_mkdir(strrchr(dn->full_name, '/') + 1, dn->parent->pde);
> +	if (ent)
> +		proc_device_tree_add_node(dn, ent);
> +#endif
> +
> +	of_node_put(dn->parent);
> +	return 0;
> +}
> +
> +int dlpar_detach_node(struct device_node *dn)
> +{
> +	struct device_node *parent = dn->parent;
> +	struct property *prop = dn->properties;
> +
> +#ifdef CONFIG_PROC_DEVICETREE
> +	while (prop) {
> +		remove_proc_entry(prop->name, dn->pde);
> +		prop = prop->next;
> +	}
> +
> +	if (dn->pde)
> +		remove_proc_entry(dn->pde->name, parent->pde);
> +#endif
> +
> +	blocking_notifier_call_chain(&pSeries_reconfig_chain,
> +			    PSERIES_RECONFIG_REMOVE, dn);
> +	of_detach_node(dn);
> +	of_node_put(dn); /* Must decrement the refcount */
> +
> +	return 0;
> +}
> +
> +#define DR_ENTITY_SENSE		9003
> +#define DR_ENTITY_PRESENT	1
> +#define DR_ENTITY_UNUSABLE	2
> +#define ALLOCATION_STATE	9003
> +#define ALLOC_UNUSABLE		0
> +#define ALLOC_USABLE		1
> +#define ISOLATION_STATE		9001
> +#define ISOLATE			0
> +#define UNISOLATE		1
> +
> +int dlpar_acquire_drc(u32 drc_index)
> +{
> +	int dr_status, rc;
> +
> +	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
> +		       DR_ENTITY_SENSE, drc_index);
> +	if (rc || dr_status != DR_ENTITY_UNUSABLE)
> +		return -1;
> +
> +	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
> +	if (rc)
> +		return rc;
> +
> +	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
> +	if (rc) {
> +		rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE)
;
> +		return rc;
> +	}
> +
> +	return 0;
> +}
> +
> +int dlpar_release_drc(u32 drc_index)
> +{
> +	int dr_status, rc;
> +
> +	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
> +		       DR_ENTITY_SENSE, drc_index);
> +	if (rc || dr_status != DR_ENTITY_PRESENT)
> +		return -1;
> +
> +	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
> +	if (rc)
> +		return rc;
> +
> +	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
> +	if (rc) {
> +		rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
> +		return rc;
> +	}
> +
> +	return 0;
> +}
> +
> +
> Index: powerpc/arch/powerpc/platforms/pseries/Makefile
> ===================================================================
> --- powerpc.orig/arch/powerpc/platforms/pseries/Makefile	2009-11-20 17:5
3:54.000000000 -0600
> +++ powerpc/arch/powerpc/platforms/pseries/Makefile	2009-11-20 17:55:52.000
000000 -0600
> @@ -8,7 +8,7 @@
>  
>  obj-y			:= lpar.o hvCall.o nvram.o reconfig.o \
>  			   setup.o iommu.o ras.o rtasd.o \
> -			   firmware.o power.o
> +			   firmware.o power.o dlpar.o
>  obj-$(CONFIG_SMP)	+= smp.o
>  obj-$(CONFIG_XICS)	+= xics.o
>  obj-$(CONFIG_SCANLOG)	+= scanlog.o
> Index: powerpc/arch/powerpc/include/asm/pSeries_reconfig.h
> ===================================================================
> --- powerpc.orig/arch/powerpc/include/asm/pSeries_reconfig.h	2009-11-20 17:5
3:54.000000000 -0600
> +++ powerpc/arch/powerpc/include/asm/pSeries_reconfig.h	2009-11-20 17:5
5:52.000000000 -0600
> @@ -17,6 +17,7 @@
>  #ifdef CONFIG_PPC_PSERIES
>  extern int pSeries_reconfig_notifier_register(struct notifier_block *);
>  extern void pSeries_reconfig_notifier_unregister(struct notifier_block *);
> +extern struct blocking_notifier_head pSeries_reconfig_chain;
>  #else /* !CONFIG_PPC_PSERIES */
>  static inline int pSeries_reconfig_notifier_register(struct notifier_block *
nb)
>  {
> Index: powerpc/arch/powerpc/platforms/pseries/reconfig.c
> ===================================================================
> --- powerpc.orig/arch/powerpc/platforms/pseries/reconfig.c	2009-11-20 17:5
3:54.000000000 -0600
> +++ powerpc/arch/powerpc/platforms/pseries/reconfig.c	2009-11-20 17:55:52.000
000000 -0600
> @@ -96,7 +96,7 @@
>  	return parent;
>  }
>  
> -static BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
> +BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
>  
>  int pSeries_reconfig_notifier_register(struct notifier_block *nb)
>  {
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/linuxppc-dev
> 

Re: [PATCH 1/3] Kernel DLPAR infrastructure

[Michael Neuling]

In message <31581.1259115310@neuling.org> you wrote:
> 
> 
> In message <4B0C8CE3.4010207@austin.ibm.com> you wrote:
> > This patch provides the kernel DLPAR infrastructure in a new filed named
> > dlpar.c.  The functionality provided is for acquiring and releasing a resou
rc
> e
> > from firmware and the parsing of information returned from the
> > ibm,configure-connector rtas call.  Additionally this exports the pSeries
> > reconfiguration notifier chain so that it can be invoked when device tree 
> > updates are made.
> > 
> > Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com> 
> 
> These look like they got white space munged somewhere...

Gah, sorry, they are fine

Mikey

Re: [PATCH 0/3] Kernel handling of Dynamic Logical Partitioning

[Paul Mackerras]

Nathan Fontenot writes:

> The Dynamic Logical Partitioning (DLPAR) capabilities of the powerpc pseries
> platform allows for the addition and removal of resources (i.e. cpus,
> memory, pci devices) from a partition. The removal of a resource involves
> removing the resource's node from the device tree and then returning the
> resource to firmware via the rtas set-indicator call.  To add a resource, it
> is first obtained from firmware via the rtas set-indicator call and then a
> new device tree node is created using the ibm,configure-coinnector rtas call
> and added to the device tree.
> 
> The following set of patches implements the needed infrastructure to have the
> kernel handle the DLPAR addition and removal of cpus (other DLPAR'able items 
> to follow in future patches).  The framework for this is to create a set of 
> probe/release sysfs files that will facilitate arch-specific call-outs to 
> handle addition and removal of cpus to the system.

Nice explanation, but the 0/3 of the series doesn't go into git.
Could you rework some/all of this into the commit message for patch
1/3 so it gets stored permanently with these patches in git?

Thanks,
Paul.

Re: [PATCH 1/3] Kernel DLPAR infrastructure

[Paul Mackerras]

Nathan Fontenot writes:

> This patch provides the kernel DLPAR infrastructure in a new filed named
> dlpar.c.  The functionality provided is for acquiring and releasing a resource
> from firmware and the parsing of information returned from the
> ibm,configure-connector rtas call.  Additionally this exports the pSeries
> reconfiguration notifier chain so that it can be invoked when device tree 
> updates are made.

Mostly looks great.

> +static struct device_node *derive_parent(const char *path)
> +{
> +	struct device_node *parent;
> +	char parent_path[128];
> +	int parent_path_len;
> +
> +	parent_path_len = strrchr(path, '/') - path + 1;
> +	strlcpy(parent_path, path, parent_path_len);

This looks a bit fragile if path could possibly not contain any '/' or
if the '/' is more than 128 characters from the start of path.  Please
fix this to check if strrchr returns NULL and to cope in some
reasonable fashion if the path happens to be very long.

> +#ifdef CONFIG_PROC_DEVICETREE
> +	ent = proc_mkdir(strrchr(dn->full_name, '/') + 1, dn->parent->pde);
> +	if (ent)
> +		proc_device_tree_add_node(dn, ent);

Also assumes that dn->full_name contains a '/'.  If for some reason it
couldn't possibly not contain a '/', put in a comment explaining that.

Thanks,
Paul.

Re: [PATCH 2/3] sysfs cpu probe/release files

[Paul Mackerras]

Nathan Fontenot writes:

> Create new probe and release sysfs files to facilitate adding and removing
> cpus from the system.  This also creates the powerpc specific stubs to handle
> the arch callouts from writes to the sysfs files.
> 
> The creation and use of these files is regulated by the 
> CONFIG_ARCH_CPU_PROBE_RELEASE option so that only architectures that need the
> capability will have the files created.
> 
> Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
> ---
>  arch/powerpc/Kconfig               |    4 ++++
>  arch/powerpc/include/asm/machdep.h |    5 +++++
>  arch/powerpc/kernel/sysfs.c        |   19 +++++++++++++++++++
>  drivers/base/cpu.c                 |   32 ++++++++++++++++++++++++++++++++

Since this touches drivers/base/cpu.c, you should cc Greg KH on this
patch and get an ack from him, assuming these patches are going in
through the powerpc tree.

> --- powerpc.orig/include/linux/cpu.h	2009-11-23 18:19:23.000000000 -0600
> +++ powerpc/include/linux/cpu.h	2009-11-24 14:30:07.000000000 -0600
> @@ -43,6 +43,10 @@
>  
>  #ifdef CONFIG_HOTPLUG_CPU
>  extern void unregister_cpu(struct cpu *cpu);
> +#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
> +extern ssize_t arch_cpu_probe(const char *, size_t);
> +extern ssize_t arch_cpu_release(const char *, size_t);
> +#endif

Since these are just declarations, they don't need the #ifdef around
them.

Paul.

Re: [PATCH 3/3] CPU DLPAR handling

[Paul Mackerras]

Nathan Fontenot writes:

> Register the pseries specific handlers for the powerpc architecture handlers
> for the cpu probe and release files.  This also implements the cpu DLPAR
> addition and removal of CPUS from the system.

...

> +	/* configure-connector reports cpus as living in the base
> +	 * directory of the device tree.  CPUs actually live in the
> +	 * cpus directory so we need to fixup the full_name.
> +	 */
> +	cpu_name = kzalloc(strlen(dn->full_name) + strlen("/cpus/") + 1,
> +			   GFP_KERNEL);
> +	if (!cpu_name) {
> +		dlpar_free_cc_nodes(dn);
> +		return -ENOMEM;
> +	}
> +
> +	sprintf(cpu_name, "/cpus/%s", dn->full_name);

I would have expected dn->full_name to start with a '/' already, in
which case this will end up with two consecutive slashes after
'cpus'.  I think that will probably cause problems.

Paul.

Re: [PATCH 0/3] Kernel handling of Dynamic Logical Partitioning

[Nathan Fontenot]

Paul Mackerras wrote:
> Nathan Fontenot writes:
> 
>> The Dynamic Logical Partitioning (DLPAR) capabilities of the powerpc pseries
>> platform allows for the addition and removal of resources (i.e. cpus,
>> memory, pci devices) from a partition. The removal of a resource involves
>> removing the resource's node from the device tree and then returning the
>> resource to firmware via the rtas set-indicator call.  To add a resource, it
>> is first obtained from firmware via the rtas set-indicator call and then a
>> new device tree node is created using the ibm,configure-coinnector rtas call
>> and added to the device tree.
>>
>> The following set of patches implements the needed infrastructure to have the
>> kernel handle the DLPAR addition and removal of cpus (other DLPAR'able items 
>> to follow in future patches).  The framework for this is to create a set of 
>> probe/release sysfs files that will facilitate arch-specific call-outs to 
>> handle addition and removal of cpus to the system.
> 
> Nice explanation, but the 0/3 of the series doesn't go into git.
> Could you rework some/all of this into the commit message for patch
> 1/3 so it gets stored permanently with these patches in git?
> 
> Thanks,
> Paul.

Thanks for all the feedback.

Version two of the patches are on their way based on your comments.

-Nathan Fontenot