1// SPDX-License-Identifier: GPL-2.0 2/* 3 * Basic Node interface support 4 */ 5 6#include <linux/module.h> 7#include <linux/init.h> 8#include <linux/mm.h> 9#include <linux/memory.h> 10#include <linux/vmstat.h> 11#include <linux/notifier.h> 12#include <linux/node.h> 13#include <linux/hugetlb.h> 14#include <linux/compaction.h> 15#include <linux/cpumask.h> 16#include <linux/topology.h> 17#include <linux/nodemask.h> 18#include <linux/cpu.h> 19#include <linux/device.h> 20#include <linux/pm_runtime.h> 21#include <linux/swap.h> 22#include <linux/slab.h> 23 24static struct bus_type node_subsys = { 25 .name = "node", 26 .dev_name = "node", 27}; 28 29 30static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf) 31{ 32 ssize_t n; 33 cpumask_var_t mask; 34 struct node *node_dev = to_node(dev); 35 36 /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */ 37 BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1)); 38 39 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) 40 return 0; 41 42 cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask); 43 n = cpumap_print_to_pagebuf(list, buf, mask); 44 free_cpumask_var(mask); 45 46 return n; 47} 48 49static inline ssize_t cpumap_show(struct device *dev, 50 struct device_attribute *attr, 51 char *buf) 52{ 53 return node_read_cpumap(dev, false, buf); 54} 55 56static DEVICE_ATTR_RO(cpumap); 57 58static inline ssize_t cpulist_show(struct device *dev, 59 struct device_attribute *attr, 60 char *buf) 61{ 62 return node_read_cpumap(dev, true, buf); 63} 64 65static DEVICE_ATTR_RO(cpulist); 66 67/** 68 * struct node_access_nodes - Access class device to hold user visible 69 * relationships to other nodes. 70 * @dev: Device for this memory access class 71 * @list_node: List element in the node's access list 72 * @access: The access class rank 73 * @hmem_attrs: Heterogeneous memory performance attributes 74 */ 75struct node_access_nodes { 76 struct device dev; 77 struct list_head list_node; 78 unsigned access; 79#ifdef CONFIG_HMEM_REPORTING 80 struct node_hmem_attrs hmem_attrs; 81#endif 82}; 83#define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev) 84 85static struct attribute *node_init_access_node_attrs[] = { 86 NULL, 87}; 88 89static struct attribute *node_targ_access_node_attrs[] = { 90 NULL, 91}; 92 93static const struct attribute_group initiators = { 94 .name = "initiators", 95 .attrs = node_init_access_node_attrs, 96}; 97 98static const struct attribute_group targets = { 99 .name = "targets", 100 .attrs = node_targ_access_node_attrs, 101}; 102 103static const struct attribute_group *node_access_node_groups[] = { 104 &initiators, 105 &targets, 106 NULL, 107}; 108 109static void node_remove_accesses(struct node *node) 110{ 111 struct node_access_nodes *c, *cnext; 112 113 list_for_each_entry_safe(c, cnext, &node->access_list, list_node) { 114 list_del(&c->list_node); 115 device_unregister(&c->dev); 116 } 117} 118 119static void node_access_release(struct device *dev) 120{ 121 kfree(to_access_nodes(dev)); 122} 123 124static struct node_access_nodes *node_init_node_access(struct node *node, 125 unsigned access) 126{ 127 struct node_access_nodes *access_node; 128 struct device *dev; 129 130 list_for_each_entry(access_node, &node->access_list, list_node) 131 if (access_node->access == access) 132 return access_node; 133 134 access_node = kzalloc(sizeof(*access_node), GFP_KERNEL); 135 if (!access_node) 136 return NULL; 137 138 access_node->access = access; 139 dev = &access_node->dev; 140 dev->parent = &node->dev; 141 dev->release = node_access_release; 142 dev->groups = node_access_node_groups; 143 if (dev_set_name(dev, "access%u", access)) 144 goto free; 145 146 if (device_register(dev)) 147 goto free_name; 148 149 pm_runtime_no_callbacks(dev); 150 list_add_tail(&access_node->list_node, &node->access_list); 151 return access_node; 152free_name: 153 kfree_const(dev->kobj.name); 154free: 155 kfree(access_node); 156 return NULL; 157} 158 159#ifdef CONFIG_HMEM_REPORTING 160#define ACCESS_ATTR(name) \ 161static ssize_t name##_show(struct device *dev, \ 162 struct device_attribute *attr, \ 163 char *buf) \ 164{ \ 165 return sysfs_emit(buf, "%u\n", \ 166 to_access_nodes(dev)->hmem_attrs.name); \ 167} \ 168static DEVICE_ATTR_RO(name) 169 170ACCESS_ATTR(read_bandwidth); 171ACCESS_ATTR(read_latency); 172ACCESS_ATTR(write_bandwidth); 173ACCESS_ATTR(write_latency); 174 175static struct attribute *access_attrs[] = { 176 &dev_attr_read_bandwidth.attr, 177 &dev_attr_read_latency.attr, 178 &dev_attr_write_bandwidth.attr, 179 &dev_attr_write_latency.attr, 180 NULL, 181}; 182 183/** 184 * node_set_perf_attrs - Set the performance values for given access class 185 * @nid: Node identifier to be set 186 * @hmem_attrs: Heterogeneous memory performance attributes 187 * @access: The access class the for the given attributes 188 */ 189void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, 190 unsigned access) 191{ 192 struct node_access_nodes *c; 193 struct node *node; 194 int i; 195 196 if (WARN_ON_ONCE(!node_online(nid))) 197 return; 198 199 node = node_devices[nid]; 200 c = node_init_node_access(node, access); 201 if (!c) 202 return; 203 204 c->hmem_attrs = *hmem_attrs; 205 for (i = 0; access_attrs[i] != NULL; i++) { 206 if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i], 207 "initiators")) { 208 pr_info("failed to add performance attribute to node %d\n", 209 nid); 210 break; 211 } 212 } 213} 214 215/** 216 * struct node_cache_info - Internal tracking for memory node caches 217 * @dev: Device represeting the cache level 218 * @node: List element for tracking in the node 219 * @cache_attrs:Attributes for this cache level 220 */ 221struct node_cache_info { 222 struct device dev; 223 struct list_head node; 224 struct node_cache_attrs cache_attrs; 225}; 226#define to_cache_info(device) container_of(device, struct node_cache_info, dev) 227 228#define CACHE_ATTR(name, fmt) \ 229static ssize_t name##_show(struct device *dev, \ 230 struct device_attribute *attr, \ 231 char *buf) \ 232{ \ 233 return sysfs_emit(buf, fmt "\n", \ 234 to_cache_info(dev)->cache_attrs.name); \ 235} \ 236DEVICE_ATTR_RO(name); 237 238CACHE_ATTR(size, "%llu") 239CACHE_ATTR(line_size, "%u") 240CACHE_ATTR(indexing, "%u") 241CACHE_ATTR(write_policy, "%u") 242 243static struct attribute *cache_attrs[] = { 244 &dev_attr_indexing.attr, 245 &dev_attr_size.attr, 246 &dev_attr_line_size.attr, 247 &dev_attr_write_policy.attr, 248 NULL, 249}; 250ATTRIBUTE_GROUPS(cache); 251 252static void node_cache_release(struct device *dev) 253{ 254 kfree(dev); 255} 256 257static void node_cacheinfo_release(struct device *dev) 258{ 259 struct node_cache_info *info = to_cache_info(dev); 260 kfree(info); 261} 262 263static void node_init_cache_dev(struct node *node) 264{ 265 struct device *dev; 266 267 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 268 if (!dev) 269 return; 270 271 device_initialize(dev); 272 dev->parent = &node->dev; 273 dev->release = node_cache_release; 274 if (dev_set_name(dev, "memory_side_cache")) 275 goto put_device; 276 277 if (device_add(dev)) 278 goto put_device; 279 280 pm_runtime_no_callbacks(dev); 281 node->cache_dev = dev; 282 return; 283put_device: 284 put_device(dev); 285} 286 287/** 288 * node_add_cache() - add cache attribute to a memory node 289 * @nid: Node identifier that has new cache attributes 290 * @cache_attrs: Attributes for the cache being added 291 */ 292void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs) 293{ 294 struct node_cache_info *info; 295 struct device *dev; 296 struct node *node; 297 298 if (!node_online(nid) || !node_devices[nid]) 299 return; 300 301 node = node_devices[nid]; 302 list_for_each_entry(info, &node->cache_attrs, node) { 303 if (info->cache_attrs.level == cache_attrs->level) { 304 dev_warn(&node->dev, 305 "attempt to add duplicate cache level:%d\n", 306 cache_attrs->level); 307 return; 308 } 309 } 310 311 if (!node->cache_dev) 312 node_init_cache_dev(node); 313 if (!node->cache_dev) 314 return; 315 316 info = kzalloc(sizeof(*info), GFP_KERNEL); 317 if (!info) 318 return; 319 320 dev = &info->dev; 321 device_initialize(dev); 322 dev->parent = node->cache_dev; 323 dev->release = node_cacheinfo_release; 324 dev->groups = cache_groups; 325 if (dev_set_name(dev, "index%d", cache_attrs->level)) 326 goto put_device; 327 328 info->cache_attrs = *cache_attrs; 329 if (device_add(dev)) { 330 dev_warn(&node->dev, "failed to add cache level:%d\n", 331 cache_attrs->level); 332 goto put_device; 333 } 334 pm_runtime_no_callbacks(dev); 335 list_add_tail(&info->node, &node->cache_attrs); 336 return; 337put_device: 338 put_device(dev); 339} 340 341static void node_remove_caches(struct node *node) 342{ 343 struct node_cache_info *info, *next; 344 345 if (!node->cache_dev) 346 return; 347 348 list_for_each_entry_safe(info, next, &node->cache_attrs, node) { 349 list_del(&info->node); 350 device_unregister(&info->dev); 351 } 352 device_unregister(node->cache_dev); 353} 354 355static void node_init_caches(unsigned int nid) 356{ 357 INIT_LIST_HEAD(&node_devices[nid]->cache_attrs); 358} 359#else 360static void node_init_caches(unsigned int nid) { } 361static void node_remove_caches(struct node *node) { } 362#endif 363 364#define K(x) ((x) << (PAGE_SHIFT - 10)) 365static ssize_t node_read_meminfo(struct device *dev, 366 struct device_attribute *attr, char *buf) 367{ 368 int len = 0; 369 int nid = dev->id; 370 struct pglist_data *pgdat = NODE_DATA(nid); 371 struct sysinfo i; 372 unsigned long sreclaimable, sunreclaimable; 373 374 si_meminfo_node(&i, nid); 375 sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B); 376 sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B); 377 len = sysfs_emit_at(buf, len, 378 "Node %d MemTotal: %8lu kB\n" 379 "Node %d MemFree: %8lu kB\n" 380 "Node %d MemUsed: %8lu kB\n" 381 "Node %d Active: %8lu kB\n" 382 "Node %d Inactive: %8lu kB\n" 383 "Node %d Active(anon): %8lu kB\n" 384 "Node %d Inactive(anon): %8lu kB\n" 385 "Node %d Active(file): %8lu kB\n" 386 "Node %d Inactive(file): %8lu kB\n" 387 "Node %d Unevictable: %8lu kB\n" 388 "Node %d Mlocked: %8lu kB\n", 389 nid, K(i.totalram), 390 nid, K(i.freeram), 391 nid, K(i.totalram - i.freeram), 392 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) + 393 node_page_state(pgdat, NR_ACTIVE_FILE)), 394 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) + 395 node_page_state(pgdat, NR_INACTIVE_FILE)), 396 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)), 397 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)), 398 nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)), 399 nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)), 400 nid, K(node_page_state(pgdat, NR_UNEVICTABLE)), 401 nid, K(sum_zone_node_page_state(nid, NR_MLOCK))); 402 403#ifdef CONFIG_HIGHMEM 404 len += sysfs_emit_at(buf, len, 405 "Node %d HighTotal: %8lu kB\n" 406 "Node %d HighFree: %8lu kB\n" 407 "Node %d LowTotal: %8lu kB\n" 408 "Node %d LowFree: %8lu kB\n", 409 nid, K(i.totalhigh), 410 nid, K(i.freehigh), 411 nid, K(i.totalram - i.totalhigh), 412 nid, K(i.freeram - i.freehigh)); 413#endif 414 len += sysfs_emit_at(buf, len, 415 "Node %d Dirty: %8lu kB\n" 416 "Node %d Writeback: %8lu kB\n" 417 "Node %d FilePages: %8lu kB\n" 418 "Node %d Mapped: %8lu kB\n" 419 "Node %d AnonPages: %8lu kB\n" 420 "Node %d Shmem: %8lu kB\n" 421 "Node %d KernelStack: %8lu kB\n" 422#ifdef CONFIG_SHADOW_CALL_STACK 423 "Node %d ShadowCallStack:%8lu kB\n" 424#endif 425 "Node %d PageTables: %8lu kB\n" 426 "Node %d NFS_Unstable: %8lu kB\n" 427 "Node %d Bounce: %8lu kB\n" 428 "Node %d WritebackTmp: %8lu kB\n" 429 "Node %d KReclaimable: %8lu kB\n" 430 "Node %d Slab: %8lu kB\n" 431 "Node %d SReclaimable: %8lu kB\n" 432 "Node %d SUnreclaim: %8lu kB\n" 433#ifdef CONFIG_TRANSPARENT_HUGEPAGE 434 "Node %d AnonHugePages: %8lu kB\n" 435 "Node %d ShmemHugePages: %8lu kB\n" 436 "Node %d ShmemPmdMapped: %8lu kB\n" 437 "Node %d FileHugePages: %8lu kB\n" 438 "Node %d FilePmdMapped: %8lu kB\n" 439#endif 440 , 441 nid, K(node_page_state(pgdat, NR_FILE_DIRTY)), 442 nid, K(node_page_state(pgdat, NR_WRITEBACK)), 443 nid, K(node_page_state(pgdat, NR_FILE_PAGES)), 444 nid, K(node_page_state(pgdat, NR_FILE_MAPPED)), 445 nid, K(node_page_state(pgdat, NR_ANON_MAPPED)), 446 nid, K(i.sharedram), 447 nid, node_page_state(pgdat, NR_KERNEL_STACK_KB), 448#ifdef CONFIG_SHADOW_CALL_STACK 449 nid, node_page_state(pgdat, NR_KERNEL_SCS_KB), 450#endif 451 nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)), 452 nid, 0UL, 453 nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)), 454 nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)), 455 nid, K(sreclaimable + 456 node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)), 457 nid, K(sreclaimable + sunreclaimable), 458 nid, K(sreclaimable), 459 nid, K(sunreclaimable) 460#ifdef CONFIG_TRANSPARENT_HUGEPAGE 461 , 462 nid, K(node_page_state(pgdat, NR_ANON_THPS) * 463 HPAGE_PMD_NR), 464 nid, K(node_page_state(pgdat, NR_SHMEM_THPS) * 465 HPAGE_PMD_NR), 466 nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) * 467 HPAGE_PMD_NR), 468 nid, K(node_page_state(pgdat, NR_FILE_THPS) * 469 HPAGE_PMD_NR), 470 nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED) * 471 HPAGE_PMD_NR) 472#endif 473 ); 474 len += hugetlb_report_node_meminfo(buf, len, nid); 475 return len; 476} 477 478#undef K 479static DEVICE_ATTR(meminfo, 0444, node_read_meminfo, NULL); 480 481static ssize_t node_read_numastat(struct device *dev, 482 struct device_attribute *attr, char *buf) 483{ 484 return sysfs_emit(buf, 485 "numa_hit %lu\n" 486 "numa_miss %lu\n" 487 "numa_foreign %lu\n" 488 "interleave_hit %lu\n" 489 "local_node %lu\n" 490 "other_node %lu\n", 491 sum_zone_numa_state(dev->id, NUMA_HIT), 492 sum_zone_numa_state(dev->id, NUMA_MISS), 493 sum_zone_numa_state(dev->id, NUMA_FOREIGN), 494 sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT), 495 sum_zone_numa_state(dev->id, NUMA_LOCAL), 496 sum_zone_numa_state(dev->id, NUMA_OTHER)); 497} 498static DEVICE_ATTR(numastat, 0444, node_read_numastat, NULL); 499 500static ssize_t node_read_vmstat(struct device *dev, 501 struct device_attribute *attr, char *buf) 502{ 503 int nid = dev->id; 504 struct pglist_data *pgdat = NODE_DATA(nid); 505 int i; 506 int len = 0; 507 508 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) 509 len += sysfs_emit_at(buf, len, "%s %lu\n", 510 zone_stat_name(i), 511 sum_zone_node_page_state(nid, i)); 512 513#ifdef CONFIG_NUMA 514 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) 515 len += sysfs_emit_at(buf, len, "%s %lu\n", 516 numa_stat_name(i), 517 sum_zone_numa_state(nid, i)); 518 519#endif 520 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) 521 len += sysfs_emit_at(buf, len, "%s %lu\n", 522 node_stat_name(i), 523 node_page_state_pages(pgdat, i)); 524 525 return len; 526} 527static DEVICE_ATTR(vmstat, 0444, node_read_vmstat, NULL); 528 529static ssize_t node_read_distance(struct device *dev, 530 struct device_attribute *attr, char *buf) 531{ 532 int nid = dev->id; 533 int len = 0; 534 int i; 535 536 /* 537 * buf is currently PAGE_SIZE in length and each node needs 4 chars 538 * at the most (distance + space or newline). 539 */ 540 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE); 541 542 for_each_online_node(i) { 543 len += sysfs_emit_at(buf, len, "%s%d", 544 i ? " " : "", node_distance(nid, i)); 545 } 546 547 len += sysfs_emit_at(buf, len, "\n"); 548 return len; 549} 550static DEVICE_ATTR(distance, 0444, node_read_distance, NULL); 551 552static struct attribute *node_dev_attrs[] = { 553 &dev_attr_cpumap.attr, 554 &dev_attr_cpulist.attr, 555 &dev_attr_meminfo.attr, 556 &dev_attr_numastat.attr, 557 &dev_attr_distance.attr, 558 &dev_attr_vmstat.attr, 559 NULL 560}; 561ATTRIBUTE_GROUPS(node_dev); 562 563#ifdef CONFIG_HUGETLBFS 564/* 565 * hugetlbfs per node attributes registration interface: 566 * When/if hugetlb[fs] subsystem initializes [sometime after this module], 567 * it will register its per node attributes for all online nodes with 568 * memory. It will also call register_hugetlbfs_with_node(), below, to 569 * register its attribute registration functions with this node driver. 570 * Once these hooks have been initialized, the node driver will call into 571 * the hugetlb module to [un]register attributes for hot-plugged nodes. 572 */ 573static node_registration_func_t __hugetlb_register_node; 574static node_registration_func_t __hugetlb_unregister_node; 575 576static inline bool hugetlb_register_node(struct node *node) 577{ 578 if (__hugetlb_register_node && 579 node_state(node->dev.id, N_MEMORY)) { 580 __hugetlb_register_node(node); 581 return true; 582 } 583 return false; 584} 585 586static inline void hugetlb_unregister_node(struct node *node) 587{ 588 if (__hugetlb_unregister_node) 589 __hugetlb_unregister_node(node); 590} 591 592void register_hugetlbfs_with_node(node_registration_func_t doregister, 593 node_registration_func_t unregister) 594{ 595 __hugetlb_register_node = doregister; 596 __hugetlb_unregister_node = unregister; 597} 598#else 599static inline void hugetlb_register_node(struct node *node) {} 600 601static inline void hugetlb_unregister_node(struct node *node) {} 602#endif 603 604static void node_device_release(struct device *dev) 605{ 606 struct node *node = to_node(dev); 607 608#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS) 609 /* 610 * We schedule the work only when a memory section is 611 * onlined/offlined on this node. When we come here, 612 * all the memory on this node has been offlined, 613 * so we won't enqueue new work to this work. 614 * 615 * The work is using node->node_work, so we should 616 * flush work before freeing the memory. 617 */ 618 flush_work(&node->node_work); 619#endif 620 kfree(node); 621} 622 623/* 624 * register_node - Setup a sysfs device for a node. 625 * @num - Node number to use when creating the device. 626 * 627 * Initialize and register the node device. 628 */ 629static int register_node(struct node *node, int num) 630{ 631 int error; 632 633 node->dev.id = num; 634 node->dev.bus = &node_subsys; 635 node->dev.release = node_device_release; 636 node->dev.groups = node_dev_groups; 637 error = device_register(&node->dev); 638 639 if (error) 640 put_device(&node->dev); 641 else { 642 hugetlb_register_node(node); 643 644 compaction_register_node(node); 645 } 646 return error; 647} 648 649/** 650 * unregister_node - unregister a node device 651 * @node: node going away 652 * 653 * Unregisters a node device @node. All the devices on the node must be 654 * unregistered before calling this function. 655 */ 656void unregister_node(struct node *node) 657{ 658 compaction_unregister_node(node); 659 hugetlb_unregister_node(node); /* no-op, if memoryless node */ 660 node_remove_accesses(node); 661 node_remove_caches(node); 662 device_unregister(&node->dev); 663} 664 665struct node *node_devices[MAX_NUMNODES]; 666 667/* 668 * register cpu under node 669 */ 670int register_cpu_under_node(unsigned int cpu, unsigned int nid) 671{ 672 int ret; 673 struct device *obj; 674 675 if (!node_online(nid)) 676 return 0; 677 678 obj = get_cpu_device(cpu); 679 if (!obj) 680 return 0; 681 682 ret = sysfs_create_link(&node_devices[nid]->dev.kobj, 683 &obj->kobj, 684 kobject_name(&obj->kobj)); 685 if (ret) 686 return ret; 687 688 return sysfs_create_link(&obj->kobj, 689 &node_devices[nid]->dev.kobj, 690 kobject_name(&node_devices[nid]->dev.kobj)); 691} 692 693/** 694 * register_memory_node_under_compute_node - link memory node to its compute 695 * node for a given access class. 696 * @mem_nid: Memory node number 697 * @cpu_nid: Cpu node number 698 * @access: Access class to register 699 * 700 * Description: 701 * For use with platforms that may have separate memory and compute nodes. 702 * This function will export node relationships linking which memory 703 * initiator nodes can access memory targets at a given ranked access 704 * class. 705 */ 706int register_memory_node_under_compute_node(unsigned int mem_nid, 707 unsigned int cpu_nid, 708 unsigned access) 709{ 710 struct node *init_node, *targ_node; 711 struct node_access_nodes *initiator, *target; 712 int ret; 713 714 if (!node_online(cpu_nid) || !node_online(mem_nid)) 715 return -ENODEV; 716 717 init_node = node_devices[cpu_nid]; 718 targ_node = node_devices[mem_nid]; 719 initiator = node_init_node_access(init_node, access); 720 target = node_init_node_access(targ_node, access); 721 if (!initiator || !target) 722 return -ENOMEM; 723 724 ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets", 725 &targ_node->dev.kobj, 726 dev_name(&targ_node->dev)); 727 if (ret) 728 return ret; 729 730 ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators", 731 &init_node->dev.kobj, 732 dev_name(&init_node->dev)); 733 if (ret) 734 goto err; 735 736 return 0; 737 err: 738 sysfs_remove_link_from_group(&initiator->dev.kobj, "targets", 739 dev_name(&targ_node->dev)); 740 return ret; 741} 742 743int unregister_cpu_under_node(unsigned int cpu, unsigned int nid) 744{ 745 struct device *obj; 746 747 if (!node_online(nid)) 748 return 0; 749 750 obj = get_cpu_device(cpu); 751 if (!obj) 752 return 0; 753 754 sysfs_remove_link(&node_devices[nid]->dev.kobj, 755 kobject_name(&obj->kobj)); 756 sysfs_remove_link(&obj->kobj, 757 kobject_name(&node_devices[nid]->dev.kobj)); 758 759 return 0; 760} 761 762#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE 763static int __ref get_nid_for_pfn(unsigned long pfn) 764{ 765 if (!pfn_valid_within(pfn)) 766 return -1; 767#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 768 if (system_state < SYSTEM_RUNNING) 769 return early_pfn_to_nid(pfn); 770#endif 771 return pfn_to_nid(pfn); 772} 773 774static void do_register_memory_block_under_node(int nid, 775 struct memory_block *mem_blk) 776{ 777 int ret; 778 779 /* 780 * If this memory block spans multiple nodes, we only indicate 781 * the last processed node. 782 */ 783 mem_blk->nid = nid; 784 785 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, 786 &mem_blk->dev.kobj, 787 kobject_name(&mem_blk->dev.kobj)); 788 if (ret && ret != -EEXIST) 789 dev_err_ratelimited(&node_devices[nid]->dev, 790 "can't create link to %s in sysfs (%d)\n", 791 kobject_name(&mem_blk->dev.kobj), ret); 792 793 ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj, 794 &node_devices[nid]->dev.kobj, 795 kobject_name(&node_devices[nid]->dev.kobj)); 796 if (ret && ret != -EEXIST) 797 dev_err_ratelimited(&mem_blk->dev, 798 "can't create link to %s in sysfs (%d)\n", 799 kobject_name(&node_devices[nid]->dev.kobj), 800 ret); 801} 802 803/* register memory section under specified node if it spans that node */ 804static int register_mem_block_under_node_early(struct memory_block *mem_blk, 805 void *arg) 806{ 807 unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE; 808 unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); 809 unsigned long end_pfn = start_pfn + memory_block_pfns - 1; 810 int nid = *(int *)arg; 811 unsigned long pfn; 812 813 for (pfn = start_pfn; pfn <= end_pfn; pfn++) { 814 int page_nid; 815 816 /* 817 * memory block could have several absent sections from start. 818 * skip pfn range from absent section 819 */ 820 if (!pfn_in_present_section(pfn)) { 821 pfn = round_down(pfn + PAGES_PER_SECTION, 822 PAGES_PER_SECTION) - 1; 823 continue; 824 } 825 826 /* 827 * We need to check if page belongs to nid only at the boot 828 * case because node's ranges can be interleaved. 829 */ 830 page_nid = get_nid_for_pfn(pfn); 831 if (page_nid < 0) 832 continue; 833 if (page_nid != nid) 834 continue; 835 836 do_register_memory_block_under_node(nid, mem_blk); 837 return 0; 838 } 839 /* mem section does not span the specified node */ 840 return 0; 841} 842 843/* 844 * During hotplug we know that all pages in the memory block belong to the same 845 * node. 846 */ 847static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, 848 void *arg) 849{ 850 int nid = *(int *)arg; 851 852 do_register_memory_block_under_node(nid, mem_blk); 853 return 0; 854} 855 856/* 857 * Unregister a memory block device under the node it spans. Memory blocks 858 * with multiple nodes cannot be offlined and therefore also never be removed. 859 */ 860void unregister_memory_block_under_nodes(struct memory_block *mem_blk) 861{ 862 if (mem_blk->nid == NUMA_NO_NODE) 863 return; 864 865 sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj, 866 kobject_name(&mem_blk->dev.kobj)); 867 sysfs_remove_link(&mem_blk->dev.kobj, 868 kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); 869} 870 871void link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, 872 enum meminit_context context) 873{ 874 walk_memory_blocks_func_t func; 875 876 if (context == MEMINIT_HOTPLUG) 877 func = register_mem_block_under_node_hotplug; 878 else 879 func = register_mem_block_under_node_early; 880 881 walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn), 882 (void *)&nid, func); 883 return; 884} 885 886#ifdef CONFIG_HUGETLBFS 887/* 888 * Handle per node hstate attribute [un]registration on transistions 889 * to/from memoryless state. 890 */ 891static void node_hugetlb_work(struct work_struct *work) 892{ 893 struct node *node = container_of(work, struct node, node_work); 894 895 /* 896 * We only get here when a node transitions to/from memoryless state. 897 * We can detect which transition occurred by examining whether the 898 * node has memory now. hugetlb_register_node() already check this 899 * so we try to register the attributes. If that fails, then the 900 * node has transitioned to memoryless, try to unregister the 901 * attributes. 902 */ 903 if (!hugetlb_register_node(node)) 904 hugetlb_unregister_node(node); 905} 906 907static void init_node_hugetlb_work(int nid) 908{ 909 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work); 910} 911 912static int node_memory_callback(struct notifier_block *self, 913 unsigned long action, void *arg) 914{ 915 struct memory_notify *mnb = arg; 916 int nid = mnb->status_change_nid; 917 918 switch (action) { 919 case MEM_ONLINE: 920 case MEM_OFFLINE: 921 /* 922 * offload per node hstate [un]registration to a work thread 923 * when transitioning to/from memoryless state. 924 */ 925 if (nid != NUMA_NO_NODE) 926 schedule_work(&node_devices[nid]->node_work); 927 break; 928 929 case MEM_GOING_ONLINE: 930 case MEM_GOING_OFFLINE: 931 case MEM_CANCEL_ONLINE: 932 case MEM_CANCEL_OFFLINE: 933 default: 934 break; 935 } 936 937 return NOTIFY_OK; 938} 939#endif /* CONFIG_HUGETLBFS */ 940#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ 941 942#if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \ 943 !defined(CONFIG_HUGETLBFS) 944static inline int node_memory_callback(struct notifier_block *self, 945 unsigned long action, void *arg) 946{ 947 return NOTIFY_OK; 948} 949 950static void init_node_hugetlb_work(int nid) { } 951 952#endif 953 954int __register_one_node(int nid) 955{ 956 int error; 957 int cpu; 958 959 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL); 960 if (!node_devices[nid]) 961 return -ENOMEM; 962 963 error = register_node(node_devices[nid], nid); 964 965 /* link cpu under this node */ 966 for_each_present_cpu(cpu) { 967 if (cpu_to_node(cpu) == nid) 968 register_cpu_under_node(cpu, nid); 969 } 970 971 INIT_LIST_HEAD(&node_devices[nid]->access_list); 972 /* initialize work queue for memory hot plug */ 973 init_node_hugetlb_work(nid); 974 node_init_caches(nid); 975 976 return error; 977} 978 979void unregister_one_node(int nid) 980{ 981 if (!node_devices[nid]) 982 return; 983 984 unregister_node(node_devices[nid]); 985 node_devices[nid] = NULL; 986} 987 988/* 989 * node states attributes 990 */ 991 992struct node_attr { 993 struct device_attribute attr; 994 enum node_states state; 995}; 996 997static ssize_t show_node_state(struct device *dev, 998 struct device_attribute *attr, char *buf) 999{ 1000 struct node_attr *na = container_of(attr, struct node_attr, attr); 1001 1002 return sysfs_emit(buf, "%*pbl\n", 1003 nodemask_pr_args(&node_states[na->state])); 1004} 1005 1006#define _NODE_ATTR(name, state) \ 1007 { __ATTR(name, 0444, show_node_state, NULL), state } 1008 1009static struct node_attr node_state_attr[] = { 1010 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE), 1011 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE), 1012 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY), 1013#ifdef CONFIG_HIGHMEM 1014 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY), 1015#endif 1016 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY), 1017 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU), 1018 [N_GENERIC_INITIATOR] = _NODE_ATTR(has_generic_initiator, 1019 N_GENERIC_INITIATOR), 1020}; 1021 1022static struct attribute *node_state_attrs[] = { 1023 &node_state_attr[N_POSSIBLE].attr.attr, 1024 &node_state_attr[N_ONLINE].attr.attr, 1025 &node_state_attr[N_NORMAL_MEMORY].attr.attr, 1026#ifdef CONFIG_HIGHMEM 1027 &node_state_attr[N_HIGH_MEMORY].attr.attr, 1028#endif 1029 &node_state_attr[N_MEMORY].attr.attr, 1030 &node_state_attr[N_CPU].attr.attr, 1031 &node_state_attr[N_GENERIC_INITIATOR].attr.attr, 1032 NULL 1033}; 1034 1035static struct attribute_group memory_root_attr_group = { 1036 .attrs = node_state_attrs, 1037}; 1038 1039static const struct attribute_group *cpu_root_attr_groups[] = { 1040 &memory_root_attr_group, 1041 NULL, 1042}; 1043 1044#define NODE_CALLBACK_PRI 2 /* lower than SLAB */ 1045static int __init register_node_type(void) 1046{ 1047 int ret; 1048 1049 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); 1050 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); 1051 1052 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups); 1053 if (!ret) { 1054 static struct notifier_block node_memory_callback_nb = { 1055 .notifier_call = node_memory_callback, 1056 .priority = NODE_CALLBACK_PRI, 1057 }; 1058 register_hotmemory_notifier(&node_memory_callback_nb); 1059 } 1060 1061 /* 1062 * Note: we're not going to unregister the node class if we fail 1063 * to register the node state class attribute files. 1064 */ 1065 return ret; 1066} 1067postcore_initcall(register_node_type); 1068