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-rw-r--r--drivers/base/node.c978
1 files changed, 978 insertions, 0 deletions
diff --git a/drivers/base/node.c b/drivers/base/node.c
new file mode 100644
index 0000000000..4d588f4658
--- /dev/null
+++ b/drivers/base/node.c
@@ -0,0 +1,978 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Basic Node interface support
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/memory.h>
+#include <linux/vmstat.h>
+#include <linux/notifier.h>
+#include <linux/node.h>
+#include <linux/hugetlb.h>
+#include <linux/compaction.h>
+#include <linux/cpumask.h>
+#include <linux/topology.h>
+#include <linux/nodemask.h>
+#include <linux/cpu.h>
+#include <linux/device.h>
+#include <linux/pm_runtime.h>
+#include <linux/swap.h>
+#include <linux/slab.h>
+
+static struct bus_type node_subsys = {
+ .name = "node",
+ .dev_name = "node",
+};
+
+static inline ssize_t cpumap_read(struct file *file, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct node *node_dev = to_node(dev);
+ cpumask_var_t mask;
+ ssize_t n;
+
+ if (!alloc_cpumask_var(&mask, GFP_KERNEL))
+ return 0;
+
+ cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
+ n = cpumap_print_bitmask_to_buf(buf, mask, off, count);
+ free_cpumask_var(mask);
+
+ return n;
+}
+
+static BIN_ATTR_RO(cpumap, CPUMAP_FILE_MAX_BYTES);
+
+static inline ssize_t cpulist_read(struct file *file, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct node *node_dev = to_node(dev);
+ cpumask_var_t mask;
+ ssize_t n;
+
+ if (!alloc_cpumask_var(&mask, GFP_KERNEL))
+ return 0;
+
+ cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
+ n = cpumap_print_list_to_buf(buf, mask, off, count);
+ free_cpumask_var(mask);
+
+ return n;
+}
+
+static BIN_ATTR_RO(cpulist, CPULIST_FILE_MAX_BYTES);
+
+/**
+ * struct node_access_nodes - Access class device to hold user visible
+ * relationships to other nodes.
+ * @dev: Device for this memory access class
+ * @list_node: List element in the node's access list
+ * @access: The access class rank
+ * @hmem_attrs: Heterogeneous memory performance attributes
+ */
+struct node_access_nodes {
+ struct device dev;
+ struct list_head list_node;
+ unsigned int access;
+#ifdef CONFIG_HMEM_REPORTING
+ struct node_hmem_attrs hmem_attrs;
+#endif
+};
+#define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev)
+
+static struct attribute *node_init_access_node_attrs[] = {
+ NULL,
+};
+
+static struct attribute *node_targ_access_node_attrs[] = {
+ NULL,
+};
+
+static const struct attribute_group initiators = {
+ .name = "initiators",
+ .attrs = node_init_access_node_attrs,
+};
+
+static const struct attribute_group targets = {
+ .name = "targets",
+ .attrs = node_targ_access_node_attrs,
+};
+
+static const struct attribute_group *node_access_node_groups[] = {
+ &initiators,
+ &targets,
+ NULL,
+};
+
+static void node_remove_accesses(struct node *node)
+{
+ struct node_access_nodes *c, *cnext;
+
+ list_for_each_entry_safe(c, cnext, &node->access_list, list_node) {
+ list_del(&c->list_node);
+ device_unregister(&c->dev);
+ }
+}
+
+static void node_access_release(struct device *dev)
+{
+ kfree(to_access_nodes(dev));
+}
+
+static struct node_access_nodes *node_init_node_access(struct node *node,
+ unsigned int access)
+{
+ struct node_access_nodes *access_node;
+ struct device *dev;
+
+ list_for_each_entry(access_node, &node->access_list, list_node)
+ if (access_node->access == access)
+ return access_node;
+
+ access_node = kzalloc(sizeof(*access_node), GFP_KERNEL);
+ if (!access_node)
+ return NULL;
+
+ access_node->access = access;
+ dev = &access_node->dev;
+ dev->parent = &node->dev;
+ dev->release = node_access_release;
+ dev->groups = node_access_node_groups;
+ if (dev_set_name(dev, "access%u", access))
+ goto free;
+
+ if (device_register(dev))
+ goto free_name;
+
+ pm_runtime_no_callbacks(dev);
+ list_add_tail(&access_node->list_node, &node->access_list);
+ return access_node;
+free_name:
+ kfree_const(dev->kobj.name);
+free:
+ kfree(access_node);
+ return NULL;
+}
+
+#ifdef CONFIG_HMEM_REPORTING
+#define ACCESS_ATTR(property) \
+static ssize_t property##_show(struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ return sysfs_emit(buf, "%u\n", \
+ to_access_nodes(dev)->hmem_attrs.property); \
+} \
+static DEVICE_ATTR_RO(property)
+
+ACCESS_ATTR(read_bandwidth);
+ACCESS_ATTR(read_latency);
+ACCESS_ATTR(write_bandwidth);
+ACCESS_ATTR(write_latency);
+
+static struct attribute *access_attrs[] = {
+ &dev_attr_read_bandwidth.attr,
+ &dev_attr_read_latency.attr,
+ &dev_attr_write_bandwidth.attr,
+ &dev_attr_write_latency.attr,
+ NULL,
+};
+
+/**
+ * node_set_perf_attrs - Set the performance values for given access class
+ * @nid: Node identifier to be set
+ * @hmem_attrs: Heterogeneous memory performance attributes
+ * @access: The access class the for the given attributes
+ */
+void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
+ unsigned int access)
+{
+ struct node_access_nodes *c;
+ struct node *node;
+ int i;
+
+ if (WARN_ON_ONCE(!node_online(nid)))
+ return;
+
+ node = node_devices[nid];
+ c = node_init_node_access(node, access);
+ if (!c)
+ return;
+
+ c->hmem_attrs = *hmem_attrs;
+ for (i = 0; access_attrs[i] != NULL; i++) {
+ if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i],
+ "initiators")) {
+ pr_info("failed to add performance attribute to node %d\n",
+ nid);
+ break;
+ }
+ }
+}
+
+/**
+ * struct node_cache_info - Internal tracking for memory node caches
+ * @dev: Device represeting the cache level
+ * @node: List element for tracking in the node
+ * @cache_attrs:Attributes for this cache level
+ */
+struct node_cache_info {
+ struct device dev;
+ struct list_head node;
+ struct node_cache_attrs cache_attrs;
+};
+#define to_cache_info(device) container_of(device, struct node_cache_info, dev)
+
+#define CACHE_ATTR(name, fmt) \
+static ssize_t name##_show(struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ return sysfs_emit(buf, fmt "\n", \
+ to_cache_info(dev)->cache_attrs.name); \
+} \
+static DEVICE_ATTR_RO(name);
+
+CACHE_ATTR(size, "%llu")
+CACHE_ATTR(line_size, "%u")
+CACHE_ATTR(indexing, "%u")
+CACHE_ATTR(write_policy, "%u")
+
+static struct attribute *cache_attrs[] = {
+ &dev_attr_indexing.attr,
+ &dev_attr_size.attr,
+ &dev_attr_line_size.attr,
+ &dev_attr_write_policy.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(cache);
+
+static void node_cache_release(struct device *dev)
+{
+ kfree(dev);
+}
+
+static void node_cacheinfo_release(struct device *dev)
+{
+ struct node_cache_info *info = to_cache_info(dev);
+ kfree(info);
+}
+
+static void node_init_cache_dev(struct node *node)
+{
+ struct device *dev;
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev)
+ return;
+
+ device_initialize(dev);
+ dev->parent = &node->dev;
+ dev->release = node_cache_release;
+ if (dev_set_name(dev, "memory_side_cache"))
+ goto put_device;
+
+ if (device_add(dev))
+ goto put_device;
+
+ pm_runtime_no_callbacks(dev);
+ node->cache_dev = dev;
+ return;
+put_device:
+ put_device(dev);
+}
+
+/**
+ * node_add_cache() - add cache attribute to a memory node
+ * @nid: Node identifier that has new cache attributes
+ * @cache_attrs: Attributes for the cache being added
+ */
+void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs)
+{
+ struct node_cache_info *info;
+ struct device *dev;
+ struct node *node;
+
+ if (!node_online(nid) || !node_devices[nid])
+ return;
+
+ node = node_devices[nid];
+ list_for_each_entry(info, &node->cache_attrs, node) {
+ if (info->cache_attrs.level == cache_attrs->level) {
+ dev_warn(&node->dev,
+ "attempt to add duplicate cache level:%d\n",
+ cache_attrs->level);
+ return;
+ }
+ }
+
+ if (!node->cache_dev)
+ node_init_cache_dev(node);
+ if (!node->cache_dev)
+ return;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return;
+
+ dev = &info->dev;
+ device_initialize(dev);
+ dev->parent = node->cache_dev;
+ dev->release = node_cacheinfo_release;
+ dev->groups = cache_groups;
+ if (dev_set_name(dev, "index%d", cache_attrs->level))
+ goto put_device;
+
+ info->cache_attrs = *cache_attrs;
+ if (device_add(dev)) {
+ dev_warn(&node->dev, "failed to add cache level:%d\n",
+ cache_attrs->level);
+ goto put_device;
+ }
+ pm_runtime_no_callbacks(dev);
+ list_add_tail(&info->node, &node->cache_attrs);
+ return;
+put_device:
+ put_device(dev);
+}
+
+static void node_remove_caches(struct node *node)
+{
+ struct node_cache_info *info, *next;
+
+ if (!node->cache_dev)
+ return;
+
+ list_for_each_entry_safe(info, next, &node->cache_attrs, node) {
+ list_del(&info->node);
+ device_unregister(&info->dev);
+ }
+ device_unregister(node->cache_dev);
+}
+
+static void node_init_caches(unsigned int nid)
+{
+ INIT_LIST_HEAD(&node_devices[nid]->cache_attrs);
+}
+#else
+static void node_init_caches(unsigned int nid) { }
+static void node_remove_caches(struct node *node) { }
+#endif
+
+#define K(x) ((x) << (PAGE_SHIFT - 10))
+static ssize_t node_read_meminfo(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int len = 0;
+ int nid = dev->id;
+ struct pglist_data *pgdat = NODE_DATA(nid);
+ struct sysinfo i;
+ unsigned long sreclaimable, sunreclaimable;
+ unsigned long swapcached = 0;
+
+ si_meminfo_node(&i, nid);
+ sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B);
+ sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B);
+#ifdef CONFIG_SWAP
+ swapcached = node_page_state_pages(pgdat, NR_SWAPCACHE);
+#endif
+ len = sysfs_emit_at(buf, len,
+ "Node %d MemTotal: %8lu kB\n"
+ "Node %d MemFree: %8lu kB\n"
+ "Node %d MemUsed: %8lu kB\n"
+ "Node %d SwapCached: %8lu kB\n"
+ "Node %d Active: %8lu kB\n"
+ "Node %d Inactive: %8lu kB\n"
+ "Node %d Active(anon): %8lu kB\n"
+ "Node %d Inactive(anon): %8lu kB\n"
+ "Node %d Active(file): %8lu kB\n"
+ "Node %d Inactive(file): %8lu kB\n"
+ "Node %d Unevictable: %8lu kB\n"
+ "Node %d Mlocked: %8lu kB\n",
+ nid, K(i.totalram),
+ nid, K(i.freeram),
+ nid, K(i.totalram - i.freeram),
+ nid, K(swapcached),
+ nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
+ node_page_state(pgdat, NR_ACTIVE_FILE)),
+ nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
+ node_page_state(pgdat, NR_INACTIVE_FILE)),
+ nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
+ nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
+ nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
+ nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
+ nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
+ nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
+
+#ifdef CONFIG_HIGHMEM
+ len += sysfs_emit_at(buf, len,
+ "Node %d HighTotal: %8lu kB\n"
+ "Node %d HighFree: %8lu kB\n"
+ "Node %d LowTotal: %8lu kB\n"
+ "Node %d LowFree: %8lu kB\n",
+ nid, K(i.totalhigh),
+ nid, K(i.freehigh),
+ nid, K(i.totalram - i.totalhigh),
+ nid, K(i.freeram - i.freehigh));
+#endif
+ len += sysfs_emit_at(buf, len,
+ "Node %d Dirty: %8lu kB\n"
+ "Node %d Writeback: %8lu kB\n"
+ "Node %d FilePages: %8lu kB\n"
+ "Node %d Mapped: %8lu kB\n"
+ "Node %d AnonPages: %8lu kB\n"
+ "Node %d Shmem: %8lu kB\n"
+ "Node %d KernelStack: %8lu kB\n"
+#ifdef CONFIG_SHADOW_CALL_STACK
+ "Node %d ShadowCallStack:%8lu kB\n"
+#endif
+ "Node %d PageTables: %8lu kB\n"
+ "Node %d SecPageTables: %8lu kB\n"
+ "Node %d NFS_Unstable: %8lu kB\n"
+ "Node %d Bounce: %8lu kB\n"
+ "Node %d WritebackTmp: %8lu kB\n"
+ "Node %d KReclaimable: %8lu kB\n"
+ "Node %d Slab: %8lu kB\n"
+ "Node %d SReclaimable: %8lu kB\n"
+ "Node %d SUnreclaim: %8lu kB\n"
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ "Node %d AnonHugePages: %8lu kB\n"
+ "Node %d ShmemHugePages: %8lu kB\n"
+ "Node %d ShmemPmdMapped: %8lu kB\n"
+ "Node %d FileHugePages: %8lu kB\n"
+ "Node %d FilePmdMapped: %8lu kB\n"
+#endif
+#ifdef CONFIG_UNACCEPTED_MEMORY
+ "Node %d Unaccepted: %8lu kB\n"
+#endif
+ ,
+ nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
+ nid, K(node_page_state(pgdat, NR_WRITEBACK)),
+ nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
+ nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
+ nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
+ nid, K(i.sharedram),
+ nid, node_page_state(pgdat, NR_KERNEL_STACK_KB),
+#ifdef CONFIG_SHADOW_CALL_STACK
+ nid, node_page_state(pgdat, NR_KERNEL_SCS_KB),
+#endif
+ nid, K(node_page_state(pgdat, NR_PAGETABLE)),
+ nid, K(node_page_state(pgdat, NR_SECONDARY_PAGETABLE)),
+ nid, 0UL,
+ nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
+ nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
+ nid, K(sreclaimable +
+ node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)),
+ nid, K(sreclaimable + sunreclaimable),
+ nid, K(sreclaimable),
+ nid, K(sunreclaimable)
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ ,
+ nid, K(node_page_state(pgdat, NR_ANON_THPS)),
+ nid, K(node_page_state(pgdat, NR_SHMEM_THPS)),
+ nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)),
+ nid, K(node_page_state(pgdat, NR_FILE_THPS)),
+ nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED))
+#endif
+#ifdef CONFIG_UNACCEPTED_MEMORY
+ ,
+ nid, K(sum_zone_node_page_state(nid, NR_UNACCEPTED))
+#endif
+ );
+ len += hugetlb_report_node_meminfo(buf, len, nid);
+ return len;
+}
+
+#undef K
+static DEVICE_ATTR(meminfo, 0444, node_read_meminfo, NULL);
+
+static ssize_t node_read_numastat(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ fold_vm_numa_events();
+ return sysfs_emit(buf,
+ "numa_hit %lu\n"
+ "numa_miss %lu\n"
+ "numa_foreign %lu\n"
+ "interleave_hit %lu\n"
+ "local_node %lu\n"
+ "other_node %lu\n",
+ sum_zone_numa_event_state(dev->id, NUMA_HIT),
+ sum_zone_numa_event_state(dev->id, NUMA_MISS),
+ sum_zone_numa_event_state(dev->id, NUMA_FOREIGN),
+ sum_zone_numa_event_state(dev->id, NUMA_INTERLEAVE_HIT),
+ sum_zone_numa_event_state(dev->id, NUMA_LOCAL),
+ sum_zone_numa_event_state(dev->id, NUMA_OTHER));
+}
+static DEVICE_ATTR(numastat, 0444, node_read_numastat, NULL);
+
+static ssize_t node_read_vmstat(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int nid = dev->id;
+ struct pglist_data *pgdat = NODE_DATA(nid);
+ int i;
+ int len = 0;
+
+ for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
+ len += sysfs_emit_at(buf, len, "%s %lu\n",
+ zone_stat_name(i),
+ sum_zone_node_page_state(nid, i));
+
+#ifdef CONFIG_NUMA
+ fold_vm_numa_events();
+ for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++)
+ len += sysfs_emit_at(buf, len, "%s %lu\n",
+ numa_stat_name(i),
+ sum_zone_numa_event_state(nid, i));
+
+#endif
+ for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
+ unsigned long pages = node_page_state_pages(pgdat, i);
+
+ if (vmstat_item_print_in_thp(i))
+ pages /= HPAGE_PMD_NR;
+ len += sysfs_emit_at(buf, len, "%s %lu\n", node_stat_name(i),
+ pages);
+ }
+
+ return len;
+}
+static DEVICE_ATTR(vmstat, 0444, node_read_vmstat, NULL);
+
+static ssize_t node_read_distance(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int nid = dev->id;
+ int len = 0;
+ int i;
+
+ /*
+ * buf is currently PAGE_SIZE in length and each node needs 4 chars
+ * at the most (distance + space or newline).
+ */
+ BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
+
+ for_each_online_node(i) {
+ len += sysfs_emit_at(buf, len, "%s%d",
+ i ? " " : "", node_distance(nid, i));
+ }
+
+ len += sysfs_emit_at(buf, len, "\n");
+ return len;
+}
+static DEVICE_ATTR(distance, 0444, node_read_distance, NULL);
+
+static struct attribute *node_dev_attrs[] = {
+ &dev_attr_meminfo.attr,
+ &dev_attr_numastat.attr,
+ &dev_attr_distance.attr,
+ &dev_attr_vmstat.attr,
+ NULL
+};
+
+static struct bin_attribute *node_dev_bin_attrs[] = {
+ &bin_attr_cpumap,
+ &bin_attr_cpulist,
+ NULL
+};
+
+static const struct attribute_group node_dev_group = {
+ .attrs = node_dev_attrs,
+ .bin_attrs = node_dev_bin_attrs
+};
+
+static const struct attribute_group *node_dev_groups[] = {
+ &node_dev_group,
+#ifdef CONFIG_HAVE_ARCH_NODE_DEV_GROUP
+ &arch_node_dev_group,
+#endif
+#ifdef CONFIG_MEMORY_FAILURE
+ &memory_failure_attr_group,
+#endif
+ NULL
+};
+
+static void node_device_release(struct device *dev)
+{
+ kfree(to_node(dev));
+}
+
+/*
+ * register_node - Setup a sysfs device for a node.
+ * @num - Node number to use when creating the device.
+ *
+ * Initialize and register the node device.
+ */
+static int register_node(struct node *node, int num)
+{
+ int error;
+
+ node->dev.id = num;
+ node->dev.bus = &node_subsys;
+ node->dev.release = node_device_release;
+ node->dev.groups = node_dev_groups;
+ error = device_register(&node->dev);
+
+ if (error) {
+ put_device(&node->dev);
+ } else {
+ hugetlb_register_node(node);
+ compaction_register_node(node);
+ }
+
+ return error;
+}
+
+/**
+ * unregister_node - unregister a node device
+ * @node: node going away
+ *
+ * Unregisters a node device @node. All the devices on the node must be
+ * unregistered before calling this function.
+ */
+void unregister_node(struct node *node)
+{
+ hugetlb_unregister_node(node);
+ compaction_unregister_node(node);
+ node_remove_accesses(node);
+ node_remove_caches(node);
+ device_unregister(&node->dev);
+}
+
+struct node *node_devices[MAX_NUMNODES];
+
+/*
+ * register cpu under node
+ */
+int register_cpu_under_node(unsigned int cpu, unsigned int nid)
+{
+ int ret;
+ struct device *obj;
+
+ if (!node_online(nid))
+ return 0;
+
+ obj = get_cpu_device(cpu);
+ if (!obj)
+ return 0;
+
+ ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
+ &obj->kobj,
+ kobject_name(&obj->kobj));
+ if (ret)
+ return ret;
+
+ return sysfs_create_link(&obj->kobj,
+ &node_devices[nid]->dev.kobj,
+ kobject_name(&node_devices[nid]->dev.kobj));
+}
+
+/**
+ * register_memory_node_under_compute_node - link memory node to its compute
+ * node for a given access class.
+ * @mem_nid: Memory node number
+ * @cpu_nid: Cpu node number
+ * @access: Access class to register
+ *
+ * Description:
+ * For use with platforms that may have separate memory and compute nodes.
+ * This function will export node relationships linking which memory
+ * initiator nodes can access memory targets at a given ranked access
+ * class.
+ */
+int register_memory_node_under_compute_node(unsigned int mem_nid,
+ unsigned int cpu_nid,
+ unsigned int access)
+{
+ struct node *init_node, *targ_node;
+ struct node_access_nodes *initiator, *target;
+ int ret;
+
+ if (!node_online(cpu_nid) || !node_online(mem_nid))
+ return -ENODEV;
+
+ init_node = node_devices[cpu_nid];
+ targ_node = node_devices[mem_nid];
+ initiator = node_init_node_access(init_node, access);
+ target = node_init_node_access(targ_node, access);
+ if (!initiator || !target)
+ return -ENOMEM;
+
+ ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets",
+ &targ_node->dev.kobj,
+ dev_name(&targ_node->dev));
+ if (ret)
+ return ret;
+
+ ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators",
+ &init_node->dev.kobj,
+ dev_name(&init_node->dev));
+ if (ret)
+ goto err;
+
+ return 0;
+ err:
+ sysfs_remove_link_from_group(&initiator->dev.kobj, "targets",
+ dev_name(&targ_node->dev));
+ return ret;
+}
+
+int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
+{
+ struct device *obj;
+
+ if (!node_online(nid))
+ return 0;
+
+ obj = get_cpu_device(cpu);
+ if (!obj)
+ return 0;
+
+ sysfs_remove_link(&node_devices[nid]->dev.kobj,
+ kobject_name(&obj->kobj));
+ sysfs_remove_link(&obj->kobj,
+ kobject_name(&node_devices[nid]->dev.kobj));
+
+ return 0;
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+static int __ref get_nid_for_pfn(unsigned long pfn)
+{
+#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
+ if (system_state < SYSTEM_RUNNING)
+ return early_pfn_to_nid(pfn);
+#endif
+ return pfn_to_nid(pfn);
+}
+
+static void do_register_memory_block_under_node(int nid,
+ struct memory_block *mem_blk,
+ enum meminit_context context)
+{
+ int ret;
+
+ memory_block_add_nid(mem_blk, nid, context);
+
+ ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
+ &mem_blk->dev.kobj,
+ kobject_name(&mem_blk->dev.kobj));
+ if (ret && ret != -EEXIST)
+ dev_err_ratelimited(&node_devices[nid]->dev,
+ "can't create link to %s in sysfs (%d)\n",
+ kobject_name(&mem_blk->dev.kobj), ret);
+
+ ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj,
+ &node_devices[nid]->dev.kobj,
+ kobject_name(&node_devices[nid]->dev.kobj));
+ if (ret && ret != -EEXIST)
+ dev_err_ratelimited(&mem_blk->dev,
+ "can't create link to %s in sysfs (%d)\n",
+ kobject_name(&node_devices[nid]->dev.kobj),
+ ret);
+}
+
+/* register memory section under specified node if it spans that node */
+static int register_mem_block_under_node_early(struct memory_block *mem_blk,
+ void *arg)
+{
+ unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE;
+ unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
+ unsigned long end_pfn = start_pfn + memory_block_pfns - 1;
+ int nid = *(int *)arg;
+ unsigned long pfn;
+
+ for (pfn = start_pfn; pfn <= end_pfn; pfn++) {
+ int page_nid;
+
+ /*
+ * memory block could have several absent sections from start.
+ * skip pfn range from absent section
+ */
+ if (!pfn_in_present_section(pfn)) {
+ pfn = round_down(pfn + PAGES_PER_SECTION,
+ PAGES_PER_SECTION) - 1;
+ continue;
+ }
+
+ /*
+ * We need to check if page belongs to nid only at the boot
+ * case because node's ranges can be interleaved.
+ */
+ page_nid = get_nid_for_pfn(pfn);
+ if (page_nid < 0)
+ continue;
+ if (page_nid != nid)
+ continue;
+
+ do_register_memory_block_under_node(nid, mem_blk, MEMINIT_EARLY);
+ return 0;
+ }
+ /* mem section does not span the specified node */
+ return 0;
+}
+
+/*
+ * During hotplug we know that all pages in the memory block belong to the same
+ * node.
+ */
+static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk,
+ void *arg)
+{
+ int nid = *(int *)arg;
+
+ do_register_memory_block_under_node(nid, mem_blk, MEMINIT_HOTPLUG);
+ return 0;
+}
+
+/*
+ * Unregister a memory block device under the node it spans. Memory blocks
+ * with multiple nodes cannot be offlined and therefore also never be removed.
+ */
+void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
+{
+ if (mem_blk->nid == NUMA_NO_NODE)
+ return;
+
+ sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj,
+ kobject_name(&mem_blk->dev.kobj));
+ sysfs_remove_link(&mem_blk->dev.kobj,
+ kobject_name(&node_devices[mem_blk->nid]->dev.kobj));
+}
+
+void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
+ unsigned long end_pfn,
+ enum meminit_context context)
+{
+ walk_memory_blocks_func_t func;
+
+ if (context == MEMINIT_HOTPLUG)
+ func = register_mem_block_under_node_hotplug;
+ else
+ func = register_mem_block_under_node_early;
+
+ walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn),
+ (void *)&nid, func);
+ return;
+}
+#endif /* CONFIG_MEMORY_HOTPLUG */
+
+int __register_one_node(int nid)
+{
+ int error;
+ int cpu;
+ struct node *node;
+
+ node = kzalloc(sizeof(struct node), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&node->access_list);
+ node_devices[nid] = node;
+
+ error = register_node(node_devices[nid], nid);
+
+ /* link cpu under this node */
+ for_each_present_cpu(cpu) {
+ if (cpu_to_node(cpu) == nid)
+ register_cpu_under_node(cpu, nid);
+ }
+
+ node_init_caches(nid);
+
+ return error;
+}
+
+void unregister_one_node(int nid)
+{
+ if (!node_devices[nid])
+ return;
+
+ unregister_node(node_devices[nid]);
+ node_devices[nid] = NULL;
+}
+
+/*
+ * node states attributes
+ */
+
+struct node_attr {
+ struct device_attribute attr;
+ enum node_states state;
+};
+
+static ssize_t show_node_state(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct node_attr *na = container_of(attr, struct node_attr, attr);
+
+ return sysfs_emit(buf, "%*pbl\n",
+ nodemask_pr_args(&node_states[na->state]));
+}
+
+#define _NODE_ATTR(name, state) \
+ { __ATTR(name, 0444, show_node_state, NULL), state }
+
+static struct node_attr node_state_attr[] = {
+ [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
+ [N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
+ [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
+#ifdef CONFIG_HIGHMEM
+ [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
+#endif
+ [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
+ [N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
+ [N_GENERIC_INITIATOR] = _NODE_ATTR(has_generic_initiator,
+ N_GENERIC_INITIATOR),
+};
+
+static struct attribute *node_state_attrs[] = {
+ &node_state_attr[N_POSSIBLE].attr.attr,
+ &node_state_attr[N_ONLINE].attr.attr,
+ &node_state_attr[N_NORMAL_MEMORY].attr.attr,
+#ifdef CONFIG_HIGHMEM
+ &node_state_attr[N_HIGH_MEMORY].attr.attr,
+#endif
+ &node_state_attr[N_MEMORY].attr.attr,
+ &node_state_attr[N_CPU].attr.attr,
+ &node_state_attr[N_GENERIC_INITIATOR].attr.attr,
+ NULL
+};
+
+static const struct attribute_group memory_root_attr_group = {
+ .attrs = node_state_attrs,
+};
+
+static const struct attribute_group *cpu_root_attr_groups[] = {
+ &memory_root_attr_group,
+ NULL,
+};
+
+void __init node_dev_init(void)
+{
+ int ret, i;
+
+ BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
+ BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
+
+ ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
+ if (ret)
+ panic("%s() failed to register subsystem: %d\n", __func__, ret);
+
+ /*
+ * Create all node devices, which will properly link the node
+ * to applicable memory block devices and already created cpu devices.
+ */
+ for_each_online_node(i) {
+ ret = register_one_node(i);
+ if (ret)
+ panic("%s() failed to add node: %d\n", __func__, ret);
+ }
+}