linux/arch/powerpc/platforms/pseries/dlpar.c
Akinobu Mita 3aef19f0a1 powerpc/pseries: Introduce pSeries_reconfig_notify()
This introduces pSeries_reconfig_notify() as a just wrapper of
blocking_notifier_call_chain() for pSeries_reconfig_chain.

This is a preparation to improvement of error code on reconfiguration
notifier failure.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29 17:48:22 +10:00

561 lines
11 KiB
C

/*
* 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 <linux/slab.h>
#include "offline_states.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;
};
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 = kmemdup(value, prop->length, GFP_KERNEL);
if (!prop->value) {
dlpar_free_cc_property(prop);
return NULL;
}
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;
/* The configure connector reported name does not contain a
* preceding '/', so we allocate a buffer large enough to
* prepend this to the full_name.
*/
name = (char *)ccwa + ccwa->name_offset;
dn->full_name = kasprintf(GFP_KERNEL, "/%s", name);
if (!dn->full_name) {
kfree(dn);
return NULL;
}
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);
}
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;
char *data_buf;
int cc_token;
int rc = -1;
cc_token = rtas_token("ibm,configure-connector");
if (cc_token == RTAS_UNKNOWN_SERVICE)
return NULL;
data_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
if (!data_buf)
return NULL;
ccwa = (struct cc_workarea *)&data_buf[0];
ccwa->drc_index = drc_index;
ccwa->zero = 0;
do {
/* Since we release the rtas_data_buf lock between configure
* connector calls we want to re-populate the rtas_data_buffer
* with the contents of the previous call.
*/
spin_lock(&rtas_data_buf_lock);
memcpy(rtas_data_buf, data_buf, RTAS_DATA_BUF_SIZE);
rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
memcpy(data_buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
spin_unlock(&rtas_data_buf_lock);
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;
}
} while (rc);
cc_error:
kfree(data_buf);
if (rc) {
if (first_dn)
dlpar_free_cc_nodes(first_dn);
return NULL;
}
return first_dn;
}
static struct device_node *derive_parent(const char *path)
{
struct device_node *parent;
char *last_slash;
last_slash = strrchr(path, '/');
if (last_slash == path) {
parent = of_find_node_by_path("/");
} else {
char *parent_path;
int parent_path_len = last_slash - path + 1;
parent_path = kmalloc(parent_path_len, GFP_KERNEL);
if (!parent_path)
return NULL;
strlcpy(parent_path, path, parent_path_len);
parent = of_find_node_by_path(parent_path);
kfree(parent_path);
}
return parent;
}
int dlpar_attach_node(struct device_node *dn)
{
#ifdef CONFIG_PROC_DEVICETREE
struct proc_dir_entry *ent;
#endif
int rc;
of_node_set_flag(dn, OF_DYNAMIC);
kref_init(&dn->kref);
dn->parent = derive_parent(dn->full_name);
if (!dn->parent)
return -ENOMEM;
rc = pSeries_reconfig_notify(PSERIES_RECONFIG_ADD, dn);
if (rc) {
printk(KERN_ERR "Failed to add device node %s\n",
dn->full_name);
return rc;
}
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)
{
#ifdef CONFIG_PROC_DEVICETREE
struct device_node *parent = dn->parent;
struct property *prop = dn->properties;
while (prop) {
remove_proc_entry(prop->name, dn->pde);
prop = prop->next;
}
if (dn->pde)
remove_proc_entry(dn->pde->name, parent->pde);
#endif
pSeries_reconfig_notify(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;
}
#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 u32 *intserv;
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++) {
for_each_present_cpu(cpu) {
if (get_hard_smp_processor_id(cpu) != intserv[i])
continue;
BUG_ON(get_cpu_current_state(cpu)
!= CPU_STATE_OFFLINE);
cpu_maps_update_done();
rc = cpu_up(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", intserv[i]);
}
cpu_maps_update_done();
out:
return rc;
}
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;
cpu_hotplug_driver_lock();
rc = strict_strtoul(buf, 0, &drc_index);
if (rc) {
rc = -EINVAL;
goto out;
}
dn = dlpar_configure_connector(drc_index);
if (!dn) {
rc = -EINVAL;
goto out;
}
/* 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 = kasprintf(GFP_KERNEL, "/cpus%s", dn->full_name);
if (!cpu_name) {
dlpar_free_cc_nodes(dn);
rc = -ENOMEM;
goto out;
}
kfree(dn->full_name);
dn->full_name = cpu_name;
rc = dlpar_acquire_drc(drc_index);
if (rc) {
dlpar_free_cc_nodes(dn);
rc = -EINVAL;
goto out;
}
rc = dlpar_attach_node(dn);
if (rc) {
dlpar_release_drc(drc_index);
dlpar_free_cc_nodes(dn);
goto out;
}
rc = dlpar_online_cpu(dn);
out:
cpu_hotplug_driver_unlock();
return rc ? rc : count;
}
static int dlpar_offline_cpu(struct device_node *dn)
{
int rc = 0;
unsigned int cpu;
int len, nthreads, i;
const u32 *intserv;
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++) {
for_each_present_cpu(cpu) {
if (get_hard_smp_processor_id(cpu) != intserv[i])
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 = cpu_down(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, intserv[i])
!= 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", intserv[i]);
}
cpu_maps_update_done();
out:
return rc;
}
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;
}
cpu_hotplug_driver_lock();
rc = dlpar_offline_cpu(dn);
if (rc) {
of_node_put(dn);
rc = -EINVAL;
goto out;
}
rc = dlpar_release_drc(*drc_index);
if (rc) {
of_node_put(dn);
goto out;
}
rc = dlpar_detach_node(dn);
if (rc) {
dlpar_acquire_drc(*drc_index);
goto out;
}
of_node_put(dn);
out:
cpu_hotplug_driver_unlock();
return rc ? rc : 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 */