mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-06 06:26:40 +07:00
a96dfddbcc
Reading a sysfs "memoryN/valid_zones" file leads to the following oops
when the first page of a range is not backed by struct page.
show_valid_zones() assumes that 'start_pfn' is always valid for
page_zone().
BUG: unable to handle kernel paging request at ffffea017a000000
IP: show_valid_zones+0x6f/0x160
This issue may happen on x86-64 systems with 64GiB or more memory since
their memory block size is bumped up to 2GiB. [1] An example of such
systems is desribed below. 0x3240000000 is only aligned by 1GiB and
this memory block starts from 0x3200000000, which is not backed by
struct page.
BIOS-e820: [mem 0x0000003240000000-0x000000603fffffff] usable
Since test_pages_in_a_zone() already checks holes, fix this issue by
extending this function to return 'valid_start' and 'valid_end' for a
given range. show_valid_zones() then proceeds with the valid range.
[1] 'Commit bdee237c03
("x86: mm: Use 2GB memory block size on
large-memory x86-64 systems")'
Link: http://lkml.kernel.org/r/20170127222149.30893-3-toshi.kani@hpe.com
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Zhang Zhen <zhenzhang.zhang@huawei.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org> [4.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
834 lines
20 KiB
C
834 lines
20 KiB
C
/*
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* Memory subsystem support
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*
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* Written by Matt Tolentino <matthew.e.tolentino@intel.com>
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* Dave Hansen <haveblue@us.ibm.com>
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*
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* This file provides the necessary infrastructure to represent
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* a SPARSEMEM-memory-model system's physical memory in /sysfs.
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* All arch-independent code that assumes MEMORY_HOTPLUG requires
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* SPARSEMEM should be contained here, or in mm/memory_hotplug.c.
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/topology.h>
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#include <linux/capability.h>
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#include <linux/device.h>
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#include <linux/memory.h>
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#include <linux/memory_hotplug.h>
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#include <linux/mm.h>
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#include <linux/mutex.h>
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#include <linux/stat.h>
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#include <linux/slab.h>
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#include <linux/atomic.h>
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#include <linux/uaccess.h>
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static DEFINE_MUTEX(mem_sysfs_mutex);
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#define MEMORY_CLASS_NAME "memory"
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#define to_memory_block(dev) container_of(dev, struct memory_block, dev)
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static int sections_per_block;
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static inline int base_memory_block_id(int section_nr)
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{
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return section_nr / sections_per_block;
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}
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static int memory_subsys_online(struct device *dev);
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static int memory_subsys_offline(struct device *dev);
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static struct bus_type memory_subsys = {
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.name = MEMORY_CLASS_NAME,
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.dev_name = MEMORY_CLASS_NAME,
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.online = memory_subsys_online,
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.offline = memory_subsys_offline,
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};
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static BLOCKING_NOTIFIER_HEAD(memory_chain);
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int register_memory_notifier(struct notifier_block *nb)
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{
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return blocking_notifier_chain_register(&memory_chain, nb);
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}
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EXPORT_SYMBOL(register_memory_notifier);
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void unregister_memory_notifier(struct notifier_block *nb)
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{
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blocking_notifier_chain_unregister(&memory_chain, nb);
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}
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EXPORT_SYMBOL(unregister_memory_notifier);
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static ATOMIC_NOTIFIER_HEAD(memory_isolate_chain);
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int register_memory_isolate_notifier(struct notifier_block *nb)
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{
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return atomic_notifier_chain_register(&memory_isolate_chain, nb);
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}
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EXPORT_SYMBOL(register_memory_isolate_notifier);
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void unregister_memory_isolate_notifier(struct notifier_block *nb)
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{
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atomic_notifier_chain_unregister(&memory_isolate_chain, nb);
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}
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EXPORT_SYMBOL(unregister_memory_isolate_notifier);
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static void memory_block_release(struct device *dev)
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{
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struct memory_block *mem = to_memory_block(dev);
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kfree(mem);
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}
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unsigned long __weak memory_block_size_bytes(void)
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{
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return MIN_MEMORY_BLOCK_SIZE;
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}
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static unsigned long get_memory_block_size(void)
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{
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unsigned long block_sz;
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block_sz = memory_block_size_bytes();
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/* Validate blk_sz is a power of 2 and not less than section size */
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if ((block_sz & (block_sz - 1)) || (block_sz < MIN_MEMORY_BLOCK_SIZE)) {
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WARN_ON(1);
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block_sz = MIN_MEMORY_BLOCK_SIZE;
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}
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return block_sz;
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}
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/*
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* use this as the physical section index that this memsection
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* uses.
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*/
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static ssize_t show_mem_start_phys_index(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct memory_block *mem = to_memory_block(dev);
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unsigned long phys_index;
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phys_index = mem->start_section_nr / sections_per_block;
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return sprintf(buf, "%08lx\n", phys_index);
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}
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/*
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* Show whether the section of memory is likely to be hot-removable
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*/
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static ssize_t show_mem_removable(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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unsigned long i, pfn;
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int ret = 1;
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struct memory_block *mem = to_memory_block(dev);
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for (i = 0; i < sections_per_block; i++) {
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if (!present_section_nr(mem->start_section_nr + i))
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continue;
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pfn = section_nr_to_pfn(mem->start_section_nr + i);
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ret &= is_mem_section_removable(pfn, PAGES_PER_SECTION);
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}
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return sprintf(buf, "%d\n", ret);
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}
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/*
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* online, offline, going offline, etc.
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*/
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static ssize_t show_mem_state(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct memory_block *mem = to_memory_block(dev);
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ssize_t len = 0;
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/*
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* We can probably put these states in a nice little array
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* so that they're not open-coded
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*/
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switch (mem->state) {
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case MEM_ONLINE:
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len = sprintf(buf, "online\n");
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break;
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case MEM_OFFLINE:
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len = sprintf(buf, "offline\n");
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break;
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case MEM_GOING_OFFLINE:
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len = sprintf(buf, "going-offline\n");
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break;
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default:
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len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
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mem->state);
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WARN_ON(1);
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break;
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}
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return len;
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}
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int memory_notify(unsigned long val, void *v)
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{
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return blocking_notifier_call_chain(&memory_chain, val, v);
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}
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int memory_isolate_notify(unsigned long val, void *v)
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{
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return atomic_notifier_call_chain(&memory_isolate_chain, val, v);
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}
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/*
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* The probe routines leave the pages reserved, just as the bootmem code does.
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* Make sure they're still that way.
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*/
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static bool pages_correctly_reserved(unsigned long start_pfn)
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{
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int i, j;
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struct page *page;
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unsigned long pfn = start_pfn;
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/*
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* memmap between sections is not contiguous except with
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* SPARSEMEM_VMEMMAP. We lookup the page once per section
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* and assume memmap is contiguous within each section
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*/
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for (i = 0; i < sections_per_block; i++, pfn += PAGES_PER_SECTION) {
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if (WARN_ON_ONCE(!pfn_valid(pfn)))
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return false;
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page = pfn_to_page(pfn);
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for (j = 0; j < PAGES_PER_SECTION; j++) {
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if (PageReserved(page + j))
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continue;
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printk(KERN_WARNING "section number %ld page number %d "
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"not reserved, was it already online?\n",
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pfn_to_section_nr(pfn), j);
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return false;
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}
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}
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return true;
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}
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/*
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* MEMORY_HOTPLUG depends on SPARSEMEM in mm/Kconfig, so it is
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* OK to have direct references to sparsemem variables in here.
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* Must already be protected by mem_hotplug_begin().
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*/
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static int
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memory_block_action(unsigned long phys_index, unsigned long action, int online_type)
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{
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unsigned long start_pfn;
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unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
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int ret;
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start_pfn = section_nr_to_pfn(phys_index);
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switch (action) {
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case MEM_ONLINE:
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if (!pages_correctly_reserved(start_pfn))
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return -EBUSY;
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ret = online_pages(start_pfn, nr_pages, online_type);
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break;
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case MEM_OFFLINE:
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ret = offline_pages(start_pfn, nr_pages);
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break;
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default:
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WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
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"%ld\n", __func__, phys_index, action, action);
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ret = -EINVAL;
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}
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return ret;
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}
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int memory_block_change_state(struct memory_block *mem,
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unsigned long to_state, unsigned long from_state_req)
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{
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int ret = 0;
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if (mem->state != from_state_req)
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return -EINVAL;
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if (to_state == MEM_OFFLINE)
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mem->state = MEM_GOING_OFFLINE;
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ret = memory_block_action(mem->start_section_nr, to_state,
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mem->online_type);
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mem->state = ret ? from_state_req : to_state;
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return ret;
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}
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/* The device lock serializes operations on memory_subsys_[online|offline] */
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static int memory_subsys_online(struct device *dev)
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{
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struct memory_block *mem = to_memory_block(dev);
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int ret;
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if (mem->state == MEM_ONLINE)
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return 0;
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/*
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* If we are called from store_mem_state(), online_type will be
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* set >= 0 Otherwise we were called from the device online
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* attribute and need to set the online_type.
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*/
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if (mem->online_type < 0)
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mem->online_type = MMOP_ONLINE_KEEP;
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/* Already under protection of mem_hotplug_begin() */
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ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
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/* clear online_type */
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mem->online_type = -1;
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return ret;
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}
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static int memory_subsys_offline(struct device *dev)
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{
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struct memory_block *mem = to_memory_block(dev);
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if (mem->state == MEM_OFFLINE)
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return 0;
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/* Can't offline block with non-present sections */
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if (mem->section_count != sections_per_block)
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return -EINVAL;
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return memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
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}
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static ssize_t
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store_mem_state(struct device *dev,
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struct device_attribute *attr, const char *buf, size_t count)
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{
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struct memory_block *mem = to_memory_block(dev);
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int ret, online_type;
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ret = lock_device_hotplug_sysfs();
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if (ret)
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return ret;
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if (sysfs_streq(buf, "online_kernel"))
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online_type = MMOP_ONLINE_KERNEL;
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else if (sysfs_streq(buf, "online_movable"))
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online_type = MMOP_ONLINE_MOVABLE;
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else if (sysfs_streq(buf, "online"))
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online_type = MMOP_ONLINE_KEEP;
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else if (sysfs_streq(buf, "offline"))
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online_type = MMOP_OFFLINE;
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else {
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ret = -EINVAL;
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goto err;
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}
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/*
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* Memory hotplug needs to hold mem_hotplug_begin() for probe to find
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* the correct memory block to online before doing device_online(dev),
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* which will take dev->mutex. Take the lock early to prevent an
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* inversion, memory_subsys_online() callbacks will be implemented by
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* assuming it's already protected.
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*/
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mem_hotplug_begin();
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switch (online_type) {
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case MMOP_ONLINE_KERNEL:
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case MMOP_ONLINE_MOVABLE:
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case MMOP_ONLINE_KEEP:
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mem->online_type = online_type;
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ret = device_online(&mem->dev);
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break;
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case MMOP_OFFLINE:
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ret = device_offline(&mem->dev);
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break;
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default:
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ret = -EINVAL; /* should never happen */
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}
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mem_hotplug_done();
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err:
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unlock_device_hotplug();
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if (ret < 0)
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return ret;
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if (ret)
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return -EINVAL;
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return count;
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}
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/*
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* phys_device is a bad name for this. What I really want
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* is a way to differentiate between memory ranges that
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* are part of physical devices that constitute
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* a complete removable unit or fru.
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* i.e. do these ranges belong to the same physical device,
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* s.t. if I offline all of these sections I can then
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* remove the physical device?
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*/
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static ssize_t show_phys_device(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct memory_block *mem = to_memory_block(dev);
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return sprintf(buf, "%d\n", mem->phys_device);
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}
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#ifdef CONFIG_MEMORY_HOTREMOVE
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static ssize_t show_valid_zones(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct memory_block *mem = to_memory_block(dev);
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unsigned long start_pfn, end_pfn;
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unsigned long valid_start, valid_end, valid_pages;
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unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
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struct zone *zone;
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int zone_shift = 0;
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start_pfn = section_nr_to_pfn(mem->start_section_nr);
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end_pfn = start_pfn + nr_pages;
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/* The block contains more than one zone can not be offlined. */
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if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start, &valid_end))
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return sprintf(buf, "none\n");
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zone = page_zone(pfn_to_page(valid_start));
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valid_pages = valid_end - valid_start;
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/* MMOP_ONLINE_KEEP */
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sprintf(buf, "%s", zone->name);
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|
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/* MMOP_ONLINE_KERNEL */
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zone_can_shift(valid_start, valid_pages, ZONE_NORMAL, &zone_shift);
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if (zone_shift) {
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strcat(buf, " ");
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strcat(buf, (zone + zone_shift)->name);
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}
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|
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/* MMOP_ONLINE_MOVABLE */
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zone_can_shift(valid_start, valid_pages, ZONE_MOVABLE, &zone_shift);
|
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if (zone_shift) {
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strcat(buf, " ");
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strcat(buf, (zone + zone_shift)->name);
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}
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|
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strcat(buf, "\n");
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|
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return strlen(buf);
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}
|
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static DEVICE_ATTR(valid_zones, 0444, show_valid_zones, NULL);
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#endif
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|
|
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static DEVICE_ATTR(phys_index, 0444, show_mem_start_phys_index, NULL);
|
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static DEVICE_ATTR(state, 0644, show_mem_state, store_mem_state);
|
|
static DEVICE_ATTR(phys_device, 0444, show_phys_device, NULL);
|
|
static DEVICE_ATTR(removable, 0444, show_mem_removable, NULL);
|
|
|
|
/*
|
|
* Block size attribute stuff
|
|
*/
|
|
static ssize_t
|
|
print_block_size(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
return sprintf(buf, "%lx\n", get_memory_block_size());
|
|
}
|
|
|
|
static DEVICE_ATTR(block_size_bytes, 0444, print_block_size, NULL);
|
|
|
|
/*
|
|
* Memory auto online policy.
|
|
*/
|
|
|
|
static ssize_t
|
|
show_auto_online_blocks(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
if (memhp_auto_online)
|
|
return sprintf(buf, "online\n");
|
|
else
|
|
return sprintf(buf, "offline\n");
|
|
}
|
|
|
|
static ssize_t
|
|
store_auto_online_blocks(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
if (sysfs_streq(buf, "online"))
|
|
memhp_auto_online = true;
|
|
else if (sysfs_streq(buf, "offline"))
|
|
memhp_auto_online = false;
|
|
else
|
|
return -EINVAL;
|
|
|
|
return count;
|
|
}
|
|
|
|
static DEVICE_ATTR(auto_online_blocks, 0644, show_auto_online_blocks,
|
|
store_auto_online_blocks);
|
|
|
|
/*
|
|
* Some architectures will have custom drivers to do this, and
|
|
* will not need to do it from userspace. The fake hot-add code
|
|
* as well as ppc64 will do all of their discovery in userspace
|
|
* and will require this interface.
|
|
*/
|
|
#ifdef CONFIG_ARCH_MEMORY_PROBE
|
|
static ssize_t
|
|
memory_probe_store(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
u64 phys_addr;
|
|
int nid, ret;
|
|
unsigned long pages_per_block = PAGES_PER_SECTION * sections_per_block;
|
|
|
|
ret = kstrtoull(buf, 0, &phys_addr);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (phys_addr & ((pages_per_block << PAGE_SHIFT) - 1))
|
|
return -EINVAL;
|
|
|
|
nid = memory_add_physaddr_to_nid(phys_addr);
|
|
ret = add_memory(nid, phys_addr,
|
|
MIN_MEMORY_BLOCK_SIZE * sections_per_block);
|
|
|
|
if (ret)
|
|
goto out;
|
|
|
|
ret = count;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static DEVICE_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
|
|
#endif
|
|
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
/*
|
|
* Support for offlining pages of memory
|
|
*/
|
|
|
|
/* Soft offline a page */
|
|
static ssize_t
|
|
store_soft_offline_page(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
int ret;
|
|
u64 pfn;
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
if (kstrtoull(buf, 0, &pfn) < 0)
|
|
return -EINVAL;
|
|
pfn >>= PAGE_SHIFT;
|
|
if (!pfn_valid(pfn))
|
|
return -ENXIO;
|
|
ret = soft_offline_page(pfn_to_page(pfn), 0);
|
|
return ret == 0 ? count : ret;
|
|
}
|
|
|
|
/* Forcibly offline a page, including killing processes. */
|
|
static ssize_t
|
|
store_hard_offline_page(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
int ret;
|
|
u64 pfn;
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
if (kstrtoull(buf, 0, &pfn) < 0)
|
|
return -EINVAL;
|
|
pfn >>= PAGE_SHIFT;
|
|
ret = memory_failure(pfn, 0, 0);
|
|
return ret ? ret : count;
|
|
}
|
|
|
|
static DEVICE_ATTR(soft_offline_page, S_IWUSR, NULL, store_soft_offline_page);
|
|
static DEVICE_ATTR(hard_offline_page, S_IWUSR, NULL, store_hard_offline_page);
|
|
#endif
|
|
|
|
/*
|
|
* Note that phys_device is optional. It is here to allow for
|
|
* differentiation between which *physical* devices each
|
|
* section belongs to...
|
|
*/
|
|
int __weak arch_get_memory_phys_device(unsigned long start_pfn)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* A reference for the returned object is held and the reference for the
|
|
* hinted object is released.
|
|
*/
|
|
struct memory_block *find_memory_block_hinted(struct mem_section *section,
|
|
struct memory_block *hint)
|
|
{
|
|
int block_id = base_memory_block_id(__section_nr(section));
|
|
struct device *hintdev = hint ? &hint->dev : NULL;
|
|
struct device *dev;
|
|
|
|
dev = subsys_find_device_by_id(&memory_subsys, block_id, hintdev);
|
|
if (hint)
|
|
put_device(&hint->dev);
|
|
if (!dev)
|
|
return NULL;
|
|
return to_memory_block(dev);
|
|
}
|
|
|
|
/*
|
|
* For now, we have a linear search to go find the appropriate
|
|
* memory_block corresponding to a particular phys_index. If
|
|
* this gets to be a real problem, we can always use a radix
|
|
* tree or something here.
|
|
*
|
|
* This could be made generic for all device subsystems.
|
|
*/
|
|
struct memory_block *find_memory_block(struct mem_section *section)
|
|
{
|
|
return find_memory_block_hinted(section, NULL);
|
|
}
|
|
|
|
static struct attribute *memory_memblk_attrs[] = {
|
|
&dev_attr_phys_index.attr,
|
|
&dev_attr_state.attr,
|
|
&dev_attr_phys_device.attr,
|
|
&dev_attr_removable.attr,
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE
|
|
&dev_attr_valid_zones.attr,
|
|
#endif
|
|
NULL
|
|
};
|
|
|
|
static struct attribute_group memory_memblk_attr_group = {
|
|
.attrs = memory_memblk_attrs,
|
|
};
|
|
|
|
static const struct attribute_group *memory_memblk_attr_groups[] = {
|
|
&memory_memblk_attr_group,
|
|
NULL,
|
|
};
|
|
|
|
/*
|
|
* register_memory - Setup a sysfs device for a memory block
|
|
*/
|
|
static
|
|
int register_memory(struct memory_block *memory)
|
|
{
|
|
memory->dev.bus = &memory_subsys;
|
|
memory->dev.id = memory->start_section_nr / sections_per_block;
|
|
memory->dev.release = memory_block_release;
|
|
memory->dev.groups = memory_memblk_attr_groups;
|
|
memory->dev.offline = memory->state == MEM_OFFLINE;
|
|
|
|
return device_register(&memory->dev);
|
|
}
|
|
|
|
static int init_memory_block(struct memory_block **memory,
|
|
struct mem_section *section, unsigned long state)
|
|
{
|
|
struct memory_block *mem;
|
|
unsigned long start_pfn;
|
|
int scn_nr;
|
|
int ret = 0;
|
|
|
|
mem = kzalloc(sizeof(*mem), GFP_KERNEL);
|
|
if (!mem)
|
|
return -ENOMEM;
|
|
|
|
scn_nr = __section_nr(section);
|
|
mem->start_section_nr =
|
|
base_memory_block_id(scn_nr) * sections_per_block;
|
|
mem->end_section_nr = mem->start_section_nr + sections_per_block - 1;
|
|
mem->state = state;
|
|
start_pfn = section_nr_to_pfn(mem->start_section_nr);
|
|
mem->phys_device = arch_get_memory_phys_device(start_pfn);
|
|
|
|
ret = register_memory(mem);
|
|
|
|
*memory = mem;
|
|
return ret;
|
|
}
|
|
|
|
static int add_memory_block(int base_section_nr)
|
|
{
|
|
struct memory_block *mem;
|
|
int i, ret, section_count = 0, section_nr;
|
|
|
|
for (i = base_section_nr;
|
|
(i < base_section_nr + sections_per_block) && i < NR_MEM_SECTIONS;
|
|
i++) {
|
|
if (!present_section_nr(i))
|
|
continue;
|
|
if (section_count == 0)
|
|
section_nr = i;
|
|
section_count++;
|
|
}
|
|
|
|
if (section_count == 0)
|
|
return 0;
|
|
ret = init_memory_block(&mem, __nr_to_section(section_nr), MEM_ONLINE);
|
|
if (ret)
|
|
return ret;
|
|
mem->section_count = section_count;
|
|
return 0;
|
|
}
|
|
|
|
static bool is_zone_device_section(struct mem_section *ms)
|
|
{
|
|
struct page *page;
|
|
|
|
page = sparse_decode_mem_map(ms->section_mem_map, __section_nr(ms));
|
|
return is_zone_device_page(page);
|
|
}
|
|
|
|
/*
|
|
* need an interface for the VM to add new memory regions,
|
|
* but without onlining it.
|
|
*/
|
|
int register_new_memory(int nid, struct mem_section *section)
|
|
{
|
|
int ret = 0;
|
|
struct memory_block *mem;
|
|
|
|
if (is_zone_device_section(section))
|
|
return 0;
|
|
|
|
mutex_lock(&mem_sysfs_mutex);
|
|
|
|
mem = find_memory_block(section);
|
|
if (mem) {
|
|
mem->section_count++;
|
|
put_device(&mem->dev);
|
|
} else {
|
|
ret = init_memory_block(&mem, section, MEM_OFFLINE);
|
|
if (ret)
|
|
goto out;
|
|
mem->section_count++;
|
|
}
|
|
|
|
if (mem->section_count == sections_per_block)
|
|
ret = register_mem_sect_under_node(mem, nid);
|
|
out:
|
|
mutex_unlock(&mem_sysfs_mutex);
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE
|
|
static void
|
|
unregister_memory(struct memory_block *memory)
|
|
{
|
|
BUG_ON(memory->dev.bus != &memory_subsys);
|
|
|
|
/* drop the ref. we got in remove_memory_block() */
|
|
put_device(&memory->dev);
|
|
device_unregister(&memory->dev);
|
|
}
|
|
|
|
static int remove_memory_section(unsigned long node_id,
|
|
struct mem_section *section, int phys_device)
|
|
{
|
|
struct memory_block *mem;
|
|
|
|
if (is_zone_device_section(section))
|
|
return 0;
|
|
|
|
mutex_lock(&mem_sysfs_mutex);
|
|
mem = find_memory_block(section);
|
|
unregister_mem_sect_under_nodes(mem, __section_nr(section));
|
|
|
|
mem->section_count--;
|
|
if (mem->section_count == 0)
|
|
unregister_memory(mem);
|
|
else
|
|
put_device(&mem->dev);
|
|
|
|
mutex_unlock(&mem_sysfs_mutex);
|
|
return 0;
|
|
}
|
|
|
|
int unregister_memory_section(struct mem_section *section)
|
|
{
|
|
if (!present_section(section))
|
|
return -EINVAL;
|
|
|
|
return remove_memory_section(0, section, 0);
|
|
}
|
|
#endif /* CONFIG_MEMORY_HOTREMOVE */
|
|
|
|
/* return true if the memory block is offlined, otherwise, return false */
|
|
bool is_memblock_offlined(struct memory_block *mem)
|
|
{
|
|
return mem->state == MEM_OFFLINE;
|
|
}
|
|
|
|
static struct attribute *memory_root_attrs[] = {
|
|
#ifdef CONFIG_ARCH_MEMORY_PROBE
|
|
&dev_attr_probe.attr,
|
|
#endif
|
|
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
&dev_attr_soft_offline_page.attr,
|
|
&dev_attr_hard_offline_page.attr,
|
|
#endif
|
|
|
|
&dev_attr_block_size_bytes.attr,
|
|
&dev_attr_auto_online_blocks.attr,
|
|
NULL
|
|
};
|
|
|
|
static struct attribute_group memory_root_attr_group = {
|
|
.attrs = memory_root_attrs,
|
|
};
|
|
|
|
static const struct attribute_group *memory_root_attr_groups[] = {
|
|
&memory_root_attr_group,
|
|
NULL,
|
|
};
|
|
|
|
/*
|
|
* Initialize the sysfs support for memory devices...
|
|
*/
|
|
int __init memory_dev_init(void)
|
|
{
|
|
unsigned int i;
|
|
int ret;
|
|
int err;
|
|
unsigned long block_sz;
|
|
|
|
ret = subsys_system_register(&memory_subsys, memory_root_attr_groups);
|
|
if (ret)
|
|
goto out;
|
|
|
|
block_sz = get_memory_block_size();
|
|
sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
|
|
|
|
/*
|
|
* Create entries for memory sections that were found
|
|
* during boot and have been initialized
|
|
*/
|
|
mutex_lock(&mem_sysfs_mutex);
|
|
for (i = 0; i < NR_MEM_SECTIONS; i += sections_per_block) {
|
|
err = add_memory_block(i);
|
|
if (!ret)
|
|
ret = err;
|
|
}
|
|
mutex_unlock(&mem_sysfs_mutex);
|
|
|
|
out:
|
|
if (ret)
|
|
printk(KERN_ERR "%s() failed: %d\n", __func__, ret);
|
|
return ret;
|
|
}
|