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 From 98d5c21c812e4e3b795f5bd912f407ed7c5e4e38 Mon Sep 17 00:00:00 2001 From: Badari Pulavarty Date: Fri, 18 Apr 2008 13:33:52 -0700 Subject: [POWERPC] Update lmb data structures for hotplug memory add/remove The powerpc kernel maintains information about logical memory blocks in the lmb.memory structure, which is initialized and updated at boot time, but not when memory is added or removed while the kernel is running. This adds a hotplug memory notifier which updates lmb.memory when memory is added or removed. This information is useful for eHEA driver to find out the memory layout and holes. NOTE: No special locking is needed for lmb_add() and lmb_remove(). Calls to these are serialized by caller. (pSeries_reconfig_chain). Signed-off-by: Badari Pulavarty Cc: Yasunori Goto Cc: Benjamin Herrenschmidt Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Paul Mackerras --- arch/powerpc/platforms/pseries/hotplug-memory.c | 43 +++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'arch/powerpc/platforms/pseries') diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c index 2d3e9a4bd6a..3c5727dd5aa 100644 --- a/arch/powerpc/platforms/pseries/hotplug-memory.c +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c @@ -10,6 +10,7 @@ */ #include +#include #include #include #include @@ -57,6 +58,11 @@ static int pseries_remove_memory(struct device_node *np) if (ret) return ret; + /* + * Update memory regions for memory remove + */ + lmb_remove(start_pfn << PAGE_SHIFT, regs[3]); + /* * Remove htab bolted mappings for this section of memory */ @@ -65,6 +71,41 @@ static int pseries_remove_memory(struct device_node *np) return ret; } +static int pseries_add_memory(struct device_node *np) +{ + const char *type; + const unsigned int *my_index; + const unsigned int *regs; + u64 start_pfn; + 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 memory index and size of the added 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); + + /* + * Update memory region to represent the memory add + */ + lmb_add(start_pfn << PAGE_SHIFT, regs[3]); + return 0; +} + static int pseries_memory_notifier(struct notifier_block *nb, unsigned long action, void *node) { @@ -72,6 +113,8 @@ static int pseries_memory_notifier(struct notifier_block *nb, switch (action) { case PSERIES_RECONFIG_ADD: + if (pseries_add_memory(node)) + err = NOTIFY_BAD; break; case PSERIES_RECONFIG_REMOVE: if (pseries_remove_memory(node)) -- cgit v1.2.3