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