David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 2 | /* |
| 3 | * acpi_numa.c - ACPI NUMA support |
| 4 | * |
| 5 | * Copyright (C) 2002 Takayoshi Kochi <t-kochi@bq.jp.nec.com> |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | #define pr_fmt(fmt) "ACPI: " fmt |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/types.h> |
| 14 | #include <linux/errno.h> |
| 15 | #include <linux/acpi.h> |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 16 | #include <linux/memblock.h> |
| 17 | #include <linux/numa.h> |
| 18 | #include <linux/nodemask.h> |
| 19 | #include <linux/topology.h> |
| 20 | |
| 21 | static nodemask_t nodes_found_map = NODE_MASK_NONE; |
| 22 | |
| 23 | /* maps to convert between proximity domain and logical node ID */ |
| 24 | static int pxm_to_node_map[MAX_PXM_DOMAINS] |
| 25 | = { [0 ... MAX_PXM_DOMAINS - 1] = NUMA_NO_NODE }; |
| 26 | static int node_to_pxm_map[MAX_NUMNODES] |
| 27 | = { [0 ... MAX_NUMNODES - 1] = PXM_INVAL }; |
| 28 | |
| 29 | unsigned char acpi_srat_revision __initdata; |
| 30 | int acpi_numa __initdata; |
| 31 | |
| 32 | int pxm_to_node(int pxm) |
| 33 | { |
| 34 | if (pxm < 0) |
| 35 | return NUMA_NO_NODE; |
| 36 | return pxm_to_node_map[pxm]; |
| 37 | } |
| 38 | |
| 39 | int node_to_pxm(int node) |
| 40 | { |
| 41 | if (node < 0) |
| 42 | return PXM_INVAL; |
| 43 | return node_to_pxm_map[node]; |
| 44 | } |
| 45 | |
| 46 | static void __acpi_map_pxm_to_node(int pxm, int node) |
| 47 | { |
| 48 | if (pxm_to_node_map[pxm] == NUMA_NO_NODE || node < pxm_to_node_map[pxm]) |
| 49 | pxm_to_node_map[pxm] = node; |
| 50 | if (node_to_pxm_map[node] == PXM_INVAL || pxm < node_to_pxm_map[node]) |
| 51 | node_to_pxm_map[node] = pxm; |
| 52 | } |
| 53 | |
| 54 | int acpi_map_pxm_to_node(int pxm) |
| 55 | { |
| 56 | int node; |
| 57 | |
| 58 | if (pxm < 0 || pxm >= MAX_PXM_DOMAINS || numa_off) |
| 59 | return NUMA_NO_NODE; |
| 60 | |
| 61 | node = pxm_to_node_map[pxm]; |
| 62 | |
| 63 | if (node == NUMA_NO_NODE) { |
| 64 | if (nodes_weight(nodes_found_map) >= MAX_NUMNODES) |
| 65 | return NUMA_NO_NODE; |
| 66 | node = first_unset_node(nodes_found_map); |
| 67 | __acpi_map_pxm_to_node(pxm, node); |
| 68 | node_set(node, nodes_found_map); |
| 69 | } |
| 70 | |
| 71 | return node; |
| 72 | } |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 73 | EXPORT_SYMBOL(acpi_map_pxm_to_node); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 74 | |
| 75 | /** |
| 76 | * acpi_map_pxm_to_online_node - Map proximity ID to online node |
| 77 | * @pxm: ACPI proximity ID |
| 78 | * |
| 79 | * This is similar to acpi_map_pxm_to_node(), but always returns an online |
| 80 | * node. When the mapped node from a given proximity ID is offline, it |
| 81 | * looks up the node distance table and returns the nearest online node. |
| 82 | * |
| 83 | * ACPI device drivers, which are called after the NUMA initialization has |
| 84 | * completed in the kernel, can call this interface to obtain their device |
| 85 | * NUMA topology from ACPI tables. Such drivers do not have to deal with |
| 86 | * offline nodes. A node may be offline when a device proximity ID is |
| 87 | * unique, SRAT memory entry does not exist, or NUMA is disabled, ex. |
| 88 | * "numa=off" on x86. |
| 89 | */ |
| 90 | int acpi_map_pxm_to_online_node(int pxm) |
| 91 | { |
| 92 | int node, min_node; |
| 93 | |
| 94 | node = acpi_map_pxm_to_node(pxm); |
| 95 | |
| 96 | if (node == NUMA_NO_NODE) |
| 97 | node = 0; |
| 98 | |
| 99 | min_node = node; |
| 100 | if (!node_online(node)) { |
| 101 | int min_dist = INT_MAX, dist, n; |
| 102 | |
| 103 | for_each_online_node(n) { |
| 104 | dist = node_distance(node, n); |
| 105 | if (dist < min_dist) { |
| 106 | min_dist = dist; |
| 107 | min_node = n; |
| 108 | } |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | return min_node; |
| 113 | } |
| 114 | EXPORT_SYMBOL(acpi_map_pxm_to_online_node); |
| 115 | |
| 116 | static void __init |
| 117 | acpi_table_print_srat_entry(struct acpi_subtable_header *header) |
| 118 | { |
| 119 | switch (header->type) { |
| 120 | case ACPI_SRAT_TYPE_CPU_AFFINITY: |
| 121 | { |
| 122 | struct acpi_srat_cpu_affinity *p = |
| 123 | (struct acpi_srat_cpu_affinity *)header; |
| 124 | pr_debug("SRAT Processor (id[0x%02x] eid[0x%02x]) in proximity domain %d %s\n", |
| 125 | p->apic_id, p->local_sapic_eid, |
| 126 | p->proximity_domain_lo, |
| 127 | (p->flags & ACPI_SRAT_CPU_ENABLED) ? |
| 128 | "enabled" : "disabled"); |
| 129 | } |
| 130 | break; |
| 131 | |
| 132 | case ACPI_SRAT_TYPE_MEMORY_AFFINITY: |
| 133 | { |
| 134 | struct acpi_srat_mem_affinity *p = |
| 135 | (struct acpi_srat_mem_affinity *)header; |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 136 | pr_debug("SRAT Memory (0x%llx length 0x%llx) in proximity domain %d %s%s%s\n", |
| 137 | (unsigned long long)p->base_address, |
| 138 | (unsigned long long)p->length, |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 139 | p->proximity_domain, |
| 140 | (p->flags & ACPI_SRAT_MEM_ENABLED) ? |
| 141 | "enabled" : "disabled", |
| 142 | (p->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) ? |
| 143 | " hot-pluggable" : "", |
| 144 | (p->flags & ACPI_SRAT_MEM_NON_VOLATILE) ? |
| 145 | " non-volatile" : ""); |
| 146 | } |
| 147 | break; |
| 148 | |
| 149 | case ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY: |
| 150 | { |
| 151 | struct acpi_srat_x2apic_cpu_affinity *p = |
| 152 | (struct acpi_srat_x2apic_cpu_affinity *)header; |
| 153 | pr_debug("SRAT Processor (x2apicid[0x%08x]) in proximity domain %d %s\n", |
| 154 | p->apic_id, |
| 155 | p->proximity_domain, |
| 156 | (p->flags & ACPI_SRAT_CPU_ENABLED) ? |
| 157 | "enabled" : "disabled"); |
| 158 | } |
| 159 | break; |
| 160 | |
| 161 | case ACPI_SRAT_TYPE_GICC_AFFINITY: |
| 162 | { |
| 163 | struct acpi_srat_gicc_affinity *p = |
| 164 | (struct acpi_srat_gicc_affinity *)header; |
| 165 | pr_debug("SRAT Processor (acpi id[0x%04x]) in proximity domain %d %s\n", |
| 166 | p->acpi_processor_uid, |
| 167 | p->proximity_domain, |
| 168 | (p->flags & ACPI_SRAT_GICC_ENABLED) ? |
| 169 | "enabled" : "disabled"); |
| 170 | } |
| 171 | break; |
| 172 | |
| 173 | default: |
| 174 | pr_warn("Found unsupported SRAT entry (type = 0x%x)\n", |
| 175 | header->type); |
| 176 | break; |
| 177 | } |
| 178 | } |
| 179 | |
| 180 | /* |
| 181 | * A lot of BIOS fill in 10 (= no distance) everywhere. This messes |
| 182 | * up the NUMA heuristics which wants the local node to have a smaller |
| 183 | * distance than the others. |
| 184 | * Do some quick checks here and only use the SLIT if it passes. |
| 185 | */ |
| 186 | static int __init slit_valid(struct acpi_table_slit *slit) |
| 187 | { |
| 188 | int i, j; |
| 189 | int d = slit->locality_count; |
| 190 | for (i = 0; i < d; i++) { |
| 191 | for (j = 0; j < d; j++) { |
| 192 | u8 val = slit->entry[d*i + j]; |
| 193 | if (i == j) { |
| 194 | if (val != LOCAL_DISTANCE) |
| 195 | return 0; |
| 196 | } else if (val <= LOCAL_DISTANCE) |
| 197 | return 0; |
| 198 | } |
| 199 | } |
| 200 | return 1; |
| 201 | } |
| 202 | |
| 203 | void __init bad_srat(void) |
| 204 | { |
| 205 | pr_err("SRAT: SRAT not used.\n"); |
| 206 | acpi_numa = -1; |
| 207 | } |
| 208 | |
| 209 | int __init srat_disabled(void) |
| 210 | { |
| 211 | return acpi_numa < 0; |
| 212 | } |
| 213 | |
| 214 | #if defined(CONFIG_X86) || defined(CONFIG_ARM64) |
| 215 | /* |
| 216 | * Callback for SLIT parsing. pxm_to_node() returns NUMA_NO_NODE for |
| 217 | * I/O localities since SRAT does not list them. I/O localities are |
| 218 | * not supported at this point. |
| 219 | */ |
| 220 | void __init acpi_numa_slit_init(struct acpi_table_slit *slit) |
| 221 | { |
| 222 | int i, j; |
| 223 | |
| 224 | for (i = 0; i < slit->locality_count; i++) { |
| 225 | const int from_node = pxm_to_node(i); |
| 226 | |
| 227 | if (from_node == NUMA_NO_NODE) |
| 228 | continue; |
| 229 | |
| 230 | for (j = 0; j < slit->locality_count; j++) { |
| 231 | const int to_node = pxm_to_node(j); |
| 232 | |
| 233 | if (to_node == NUMA_NO_NODE) |
| 234 | continue; |
| 235 | |
| 236 | numa_set_distance(from_node, to_node, |
| 237 | slit->entry[slit->locality_count * i + j]); |
| 238 | } |
| 239 | } |
| 240 | } |
| 241 | |
| 242 | /* |
| 243 | * Default callback for parsing of the Proximity Domain <-> Memory |
| 244 | * Area mappings |
| 245 | */ |
| 246 | int __init |
| 247 | acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma) |
| 248 | { |
| 249 | u64 start, end; |
| 250 | u32 hotpluggable; |
| 251 | int node, pxm; |
| 252 | |
| 253 | if (srat_disabled()) |
| 254 | goto out_err; |
| 255 | if (ma->header.length < sizeof(struct acpi_srat_mem_affinity)) { |
| 256 | pr_err("SRAT: Unexpected header length: %d\n", |
| 257 | ma->header.length); |
| 258 | goto out_err_bad_srat; |
| 259 | } |
| 260 | if ((ma->flags & ACPI_SRAT_MEM_ENABLED) == 0) |
| 261 | goto out_err; |
| 262 | hotpluggable = ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE; |
| 263 | if (hotpluggable && !IS_ENABLED(CONFIG_MEMORY_HOTPLUG)) |
| 264 | goto out_err; |
| 265 | |
| 266 | start = ma->base_address; |
| 267 | end = start + ma->length; |
| 268 | pxm = ma->proximity_domain; |
| 269 | if (acpi_srat_revision <= 1) |
| 270 | pxm &= 0xff; |
| 271 | |
| 272 | node = acpi_map_pxm_to_node(pxm); |
| 273 | if (node == NUMA_NO_NODE || node >= MAX_NUMNODES) { |
| 274 | pr_err("SRAT: Too many proximity domains.\n"); |
| 275 | goto out_err_bad_srat; |
| 276 | } |
| 277 | |
| 278 | if (numa_add_memblk(node, start, end) < 0) { |
| 279 | pr_err("SRAT: Failed to add memblk to node %u [mem %#010Lx-%#010Lx]\n", |
| 280 | node, (unsigned long long) start, |
| 281 | (unsigned long long) end - 1); |
| 282 | goto out_err_bad_srat; |
| 283 | } |
| 284 | |
| 285 | node_set(node, numa_nodes_parsed); |
| 286 | |
| 287 | pr_info("SRAT: Node %u PXM %u [mem %#010Lx-%#010Lx]%s%s\n", |
| 288 | node, pxm, |
| 289 | (unsigned long long) start, (unsigned long long) end - 1, |
| 290 | hotpluggable ? " hotplug" : "", |
| 291 | ma->flags & ACPI_SRAT_MEM_NON_VOLATILE ? " non-volatile" : ""); |
| 292 | |
| 293 | /* Mark hotplug range in memblock. */ |
| 294 | if (hotpluggable && memblock_mark_hotplug(start, ma->length)) |
| 295 | pr_warn("SRAT: Failed to mark hotplug range [mem %#010Lx-%#010Lx] in memblock\n", |
| 296 | (unsigned long long)start, (unsigned long long)end - 1); |
| 297 | |
| 298 | max_possible_pfn = max(max_possible_pfn, PFN_UP(end - 1)); |
| 299 | |
| 300 | return 0; |
| 301 | out_err_bad_srat: |
| 302 | bad_srat(); |
| 303 | out_err: |
| 304 | return -EINVAL; |
| 305 | } |
| 306 | #endif /* defined(CONFIG_X86) || defined (CONFIG_ARM64) */ |
| 307 | |
| 308 | static int __init acpi_parse_slit(struct acpi_table_header *table) |
| 309 | { |
| 310 | struct acpi_table_slit *slit = (struct acpi_table_slit *)table; |
| 311 | |
| 312 | if (!slit_valid(slit)) { |
| 313 | pr_info("SLIT table looks invalid. Not used.\n"); |
| 314 | return -EINVAL; |
| 315 | } |
| 316 | acpi_numa_slit_init(slit); |
| 317 | |
| 318 | return 0; |
| 319 | } |
| 320 | |
| 321 | void __init __weak |
| 322 | acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa) |
| 323 | { |
| 324 | pr_warn("Found unsupported x2apic [0x%08x] SRAT entry\n", pa->apic_id); |
| 325 | } |
| 326 | |
| 327 | static int __init |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 328 | acpi_parse_x2apic_affinity(union acpi_subtable_headers *header, |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 329 | const unsigned long end) |
| 330 | { |
| 331 | struct acpi_srat_x2apic_cpu_affinity *processor_affinity; |
| 332 | |
| 333 | processor_affinity = (struct acpi_srat_x2apic_cpu_affinity *)header; |
| 334 | if (!processor_affinity) |
| 335 | return -EINVAL; |
| 336 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 337 | acpi_table_print_srat_entry(&header->common); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 338 | |
| 339 | /* let architecture-dependent part to do it */ |
| 340 | acpi_numa_x2apic_affinity_init(processor_affinity); |
| 341 | |
| 342 | return 0; |
| 343 | } |
| 344 | |
| 345 | static int __init |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 346 | acpi_parse_processor_affinity(union acpi_subtable_headers *header, |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 347 | const unsigned long end) |
| 348 | { |
| 349 | struct acpi_srat_cpu_affinity *processor_affinity; |
| 350 | |
| 351 | processor_affinity = (struct acpi_srat_cpu_affinity *)header; |
| 352 | if (!processor_affinity) |
| 353 | return -EINVAL; |
| 354 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 355 | acpi_table_print_srat_entry(&header->common); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 356 | |
| 357 | /* let architecture-dependent part to do it */ |
| 358 | acpi_numa_processor_affinity_init(processor_affinity); |
| 359 | |
| 360 | return 0; |
| 361 | } |
| 362 | |
| 363 | static int __init |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 364 | acpi_parse_gicc_affinity(union acpi_subtable_headers *header, |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 365 | const unsigned long end) |
| 366 | { |
| 367 | struct acpi_srat_gicc_affinity *processor_affinity; |
| 368 | |
| 369 | processor_affinity = (struct acpi_srat_gicc_affinity *)header; |
| 370 | if (!processor_affinity) |
| 371 | return -EINVAL; |
| 372 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 373 | acpi_table_print_srat_entry(&header->common); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 374 | |
| 375 | /* let architecture-dependent part to do it */ |
| 376 | acpi_numa_gicc_affinity_init(processor_affinity); |
| 377 | |
| 378 | return 0; |
| 379 | } |
| 380 | |
| 381 | static int __initdata parsed_numa_memblks; |
| 382 | |
| 383 | static int __init |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 384 | acpi_parse_memory_affinity(union acpi_subtable_headers * header, |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 385 | const unsigned long end) |
| 386 | { |
| 387 | struct acpi_srat_mem_affinity *memory_affinity; |
| 388 | |
| 389 | memory_affinity = (struct acpi_srat_mem_affinity *)header; |
| 390 | if (!memory_affinity) |
| 391 | return -EINVAL; |
| 392 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 393 | acpi_table_print_srat_entry(&header->common); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 394 | |
| 395 | /* let architecture-dependent part to do it */ |
| 396 | if (!acpi_numa_memory_affinity_init(memory_affinity)) |
| 397 | parsed_numa_memblks++; |
| 398 | return 0; |
| 399 | } |
| 400 | |
| 401 | static int __init acpi_parse_srat(struct acpi_table_header *table) |
| 402 | { |
| 403 | struct acpi_table_srat *srat = (struct acpi_table_srat *)table; |
| 404 | |
| 405 | acpi_srat_revision = srat->header.revision; |
| 406 | |
| 407 | /* Real work done in acpi_table_parse_srat below. */ |
| 408 | |
| 409 | return 0; |
| 410 | } |
| 411 | |
| 412 | static int __init |
| 413 | acpi_table_parse_srat(enum acpi_srat_type id, |
| 414 | acpi_tbl_entry_handler handler, unsigned int max_entries) |
| 415 | { |
| 416 | return acpi_table_parse_entries(ACPI_SIG_SRAT, |
| 417 | sizeof(struct acpi_table_srat), id, |
| 418 | handler, max_entries); |
| 419 | } |
| 420 | |
| 421 | int __init acpi_numa_init(void) |
| 422 | { |
| 423 | int cnt = 0; |
| 424 | |
| 425 | if (acpi_disabled) |
| 426 | return -EINVAL; |
| 427 | |
| 428 | /* |
| 429 | * Should not limit number with cpu num that is from NR_CPUS or nr_cpus= |
| 430 | * SRAT cpu entries could have different order with that in MADT. |
| 431 | * So go over all cpu entries in SRAT to get apicid to node mapping. |
| 432 | */ |
| 433 | |
| 434 | /* SRAT: System Resource Affinity Table */ |
| 435 | if (!acpi_table_parse(ACPI_SIG_SRAT, acpi_parse_srat)) { |
| 436 | struct acpi_subtable_proc srat_proc[3]; |
| 437 | |
| 438 | memset(srat_proc, 0, sizeof(srat_proc)); |
| 439 | srat_proc[0].id = ACPI_SRAT_TYPE_CPU_AFFINITY; |
| 440 | srat_proc[0].handler = acpi_parse_processor_affinity; |
| 441 | srat_proc[1].id = ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY; |
| 442 | srat_proc[1].handler = acpi_parse_x2apic_affinity; |
| 443 | srat_proc[2].id = ACPI_SRAT_TYPE_GICC_AFFINITY; |
| 444 | srat_proc[2].handler = acpi_parse_gicc_affinity; |
| 445 | |
| 446 | acpi_table_parse_entries_array(ACPI_SIG_SRAT, |
| 447 | sizeof(struct acpi_table_srat), |
| 448 | srat_proc, ARRAY_SIZE(srat_proc), 0); |
| 449 | |
| 450 | cnt = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY, |
| 451 | acpi_parse_memory_affinity, 0); |
| 452 | } |
| 453 | |
| 454 | /* SLIT: System Locality Information Table */ |
| 455 | acpi_table_parse(ACPI_SIG_SLIT, acpi_parse_slit); |
| 456 | |
| 457 | if (cnt < 0) |
| 458 | return cnt; |
| 459 | else if (!parsed_numa_memblks) |
| 460 | return -ENOENT; |
| 461 | return 0; |
| 462 | } |
| 463 | |
| 464 | static int acpi_get_pxm(acpi_handle h) |
| 465 | { |
| 466 | unsigned long long pxm; |
| 467 | acpi_status status; |
| 468 | acpi_handle handle; |
| 469 | acpi_handle phandle = h; |
| 470 | |
| 471 | do { |
| 472 | handle = phandle; |
| 473 | status = acpi_evaluate_integer(handle, "_PXM", NULL, &pxm); |
| 474 | if (ACPI_SUCCESS(status)) |
| 475 | return pxm; |
| 476 | status = acpi_get_parent(handle, &phandle); |
| 477 | } while (ACPI_SUCCESS(status)); |
| 478 | return -1; |
| 479 | } |
| 480 | |
| 481 | int acpi_get_node(acpi_handle handle) |
| 482 | { |
| 483 | int pxm; |
| 484 | |
| 485 | pxm = acpi_get_pxm(handle); |
| 486 | |
| 487 | return acpi_map_pxm_to_node(pxm); |
| 488 | } |
| 489 | EXPORT_SYMBOL(acpi_get_node); |