linux_dsm_epyc7002/arch/powerpc/platforms/pseries/hotplug-memory.c
Akinobu Mita de2780a3d8 powerpc/pseries: Improve error code on reconfiguration notifier failure
Reconfiguration notifier call for device node may fail by several reasons,
but it always assumes kmalloc failures.

This enables reconfiguration notifier call chain to get the actual error
code rather than -ENOMEM by converting all reconfiguration notifier calls
to return encapsulate error code with notifier_from_errno().

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 17:48:24 +10:00

229 lines
5.1 KiB
C

/*
* pseries Memory Hotplug infrastructure.
*
* Copyright (C) 2008 Badari Pulavarty, IBM Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/of.h>
#include <linux/memblock.h>
#include <linux/vmalloc.h>
#include <asm/firmware.h>
#include <asm/machdep.h>
#include <asm/pSeries_reconfig.h>
#include <asm/sparsemem.h>
static unsigned long get_memblock_size(void)
{
struct device_node *np;
unsigned int memblock_size = 0;
np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
if (np) {
const unsigned long *size;
size = of_get_property(np, "ibm,lmb-size", NULL);
memblock_size = size ? *size : 0;
of_node_put(np);
} else {
unsigned int memzero_size = 0;
const unsigned int *regs;
np = of_find_node_by_path("/memory@0");
if (np) {
regs = of_get_property(np, "reg", NULL);
memzero_size = regs ? regs[3] : 0;
of_node_put(np);
}
if (memzero_size) {
/* We now know the size of memory@0, use this to find
* the first memoryblock and get its size.
*/
char buf[64];
sprintf(buf, "/memory@%x", memzero_size);
np = of_find_node_by_path(buf);
if (np) {
regs = of_get_property(np, "reg", NULL);
memblock_size = regs ? regs[3] : 0;
of_node_put(np);
}
}
}
return memblock_size;
}
unsigned long memory_block_size_bytes(void)
{
return get_memblock_size();
}
static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
{
unsigned long start, start_pfn;
struct zone *zone;
int ret;
start_pfn = base >> PAGE_SHIFT;
if (!pfn_valid(start_pfn)) {
memblock_remove(base, memblock_size);
return 0;
}
zone = page_zone(pfn_to_page(start_pfn));
/*
* Remove section mappings and sysfs entries for the
* section of the memory we are removing.
*
* NOTE: Ideally, this should be done in generic code like
* remove_memory(). But remove_memory() gets called by writing
* to sysfs "state" file and we can't remove sysfs entries
* while writing to it. So we have to defer it to here.
*/
ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT);
if (ret)
return ret;
/*
* Update memory regions for memory remove
*/
memblock_remove(base, memblock_size);
/*
* Remove htab bolted mappings for this section of memory
*/
start = (unsigned long)__va(base);
ret = remove_section_mapping(start, start + memblock_size);
/* Ensure all vmalloc mappings are flushed in case they also
* hit that section of memory
*/
vm_unmap_aliases();
return ret;
}
static int pseries_remove_memory(struct device_node *np)
{
const char *type;
const unsigned int *regs;
unsigned long base;
unsigned int lmb_size;
int ret = -EINVAL;
/*
* Check to see if we are actually removing memory
*/
type = of_get_property(np, "device_type", NULL);
if (type == NULL || strcmp(type, "memory") != 0)
return 0;
/*
* Find the bae address and size of the memblock
*/
regs = of_get_property(np, "reg", NULL);
if (!regs)
return ret;
base = *(unsigned long *)regs;
lmb_size = regs[3];
ret = pseries_remove_memblock(base, lmb_size);
return ret;
}
static int pseries_add_memory(struct device_node *np)
{
const char *type;
const unsigned int *regs;
unsigned long base;
unsigned int lmb_size;
int ret = -EINVAL;
/*
* Check to see if we are actually adding memory
*/
type = of_get_property(np, "device_type", NULL);
if (type == NULL || strcmp(type, "memory") != 0)
return 0;
/*
* Find the base and size of the memblock
*/
regs = of_get_property(np, "reg", NULL);
if (!regs)
return ret;
base = *(unsigned long *)regs;
lmb_size = regs[3];
/*
* Update memory region to represent the memory add
*/
ret = memblock_add(base, lmb_size);
return (ret < 0) ? -EINVAL : 0;
}
static int pseries_drconf_memory(unsigned long *base, unsigned int action)
{
unsigned long memblock_size;
int rc;
memblock_size = get_memblock_size();
if (!memblock_size)
return -EINVAL;
if (action == PSERIES_DRCONF_MEM_ADD) {
rc = memblock_add(*base, memblock_size);
rc = (rc < 0) ? -EINVAL : 0;
} else if (action == PSERIES_DRCONF_MEM_REMOVE) {
rc = pseries_remove_memblock(*base, memblock_size);
} else {
rc = -EINVAL;
}
return rc;
}
static int pseries_memory_notifier(struct notifier_block *nb,
unsigned long action, void *node)
{
int err = 0;
switch (action) {
case PSERIES_RECONFIG_ADD:
err = pseries_add_memory(node);
break;
case PSERIES_RECONFIG_REMOVE:
err = pseries_remove_memory(node);
break;
case PSERIES_DRCONF_MEM_ADD:
case PSERIES_DRCONF_MEM_REMOVE:
err = pseries_drconf_memory(node, action);
break;
}
return notifier_from_errno(err);
}
static struct notifier_block pseries_mem_nb = {
.notifier_call = pseries_memory_notifier,
};
static int __init pseries_memory_hotplug_init(void)
{
if (firmware_has_feature(FW_FEATURE_LPAR))
pSeries_reconfig_notifier_register(&pseries_mem_nb);
return 0;
}
machine_device_initcall(pseries, pseries_memory_hotplug_init);