From 57b539269e9eef4dedc533d83c94877bc6b4d44d Mon Sep 17 00:00:00 2001 From: Badari Pulavarty Date: Fri, 18 Apr 2008 13:33:50 -0700 Subject: [POWERPC] Hotplug memory remove notifications for powerpc Hotplug memory remove notifier for 64-bit powerpc. This gets invoked by writing to /proc/ppc64/ofdt the string "remove_node " followed by the firmware device tree pathname of the node that needs to be removed. In response, this adjusts the sections and removes sysfs entries by calling __remove_pages(). Then it calls arch-specific code to get rid of the hardware MMU mappings for the section of memory. Signed-off-by: Badari Pulavarty Reviewed-by: Michael Ellerman Cc: Yasunori Goto Cc: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Paul Mackerras --- arch/powerpc/platforms/pseries/Makefile | 1 + arch/powerpc/platforms/pseries/hotplug-memory.c | 98 +++++++++++++++++++++++++ 2 files changed, 99 insertions(+) create mode 100644 arch/powerpc/platforms/pseries/hotplug-memory.c (limited to 'arch/powerpc/platforms/pseries') diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile index bd2593ed28d..554c6e42ef2 100644 --- a/arch/powerpc/platforms/pseries/Makefile +++ b/arch/powerpc/platforms/pseries/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_PCI) += pci.o pci_dlpar.o obj-$(CONFIG_PCI_MSI) += msi.o obj-$(CONFIG_HOTPLUG_CPU) += hotplug-cpu.o +obj-$(CONFIG_MEMORY_HOTPLUG) += hotplug-memory.o obj-$(CONFIG_HVC_CONSOLE) += hvconsole.o obj-$(CONFIG_HVCS) += hvcserver.o diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c new file mode 100644 index 00000000000..2d3e9a4bd6a --- /dev/null +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c @@ -0,0 +1,98 @@ +/* + * 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 +#include +#include +#include + +static int pseries_remove_memory(struct device_node *np) +{ + const char *type; + const unsigned int *my_index; + const unsigned int *regs; + u64 start_pfn, start; + struct zone *zone; + 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 memory index and size of the removing section + */ + my_index = of_get_property(np, "ibm,my-drc-index", NULL); + if (!my_index) + return ret; + + regs = of_get_property(np, "reg", NULL); + if (!regs) + return ret; + + start_pfn = section_nr_to_pfn(*my_index & 0xffff); + 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, regs[3] >> PAGE_SHIFT); + if (ret) + return ret; + + /* + * Remove htab bolted mappings for this section of memory + */ + start = (unsigned long)__va(start_pfn << PAGE_SHIFT); + ret = remove_section_mapping(start, start + regs[3]); + return ret; +} + +static int pseries_memory_notifier(struct notifier_block *nb, + unsigned long action, void *node) +{ + int err = NOTIFY_OK; + + switch (action) { + case PSERIES_RECONFIG_ADD: + break; + case PSERIES_RECONFIG_REMOVE: + if (pseries_remove_memory(node)) + err = NOTIFY_BAD; + break; + default: + err = NOTIFY_DONE; + break; + } + return 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); -- cgit v1.2.3