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