1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2019, Intel Corporation.
4  *
5  * Heterogeneous Memory Attributes Table (HMAT) representation
6  *
7  * This program parses and reports the platform's HMAT tables, and registers
8  * the applicable attributes with the node's interfaces.
9  */
10 
11 #include <linux/acpi.h>
12 #include <linux/bitops.h>
13 #include <linux/device.h>
14 #include <linux/init.h>
15 #include <linux/list.h>
16 #include <linux/list_sort.h>
17 #include <linux/memory.h>
18 #include <linux/mutex.h>
19 #include <linux/node.h>
20 #include <linux/sysfs.h>
21 
22 static u8 hmat_revision;
23 
24 static LIST_HEAD(targets);
25 static LIST_HEAD(initiators);
26 static LIST_HEAD(localities);
27 
28 static DEFINE_MUTEX(target_lock);
29 
30 /*
31  * The defined enum order is used to prioritize attributes to break ties when
32  * selecting the best performing node.
33  */
34 enum locality_types {
35 	WRITE_LATENCY,
36 	READ_LATENCY,
37 	WRITE_BANDWIDTH,
38 	READ_BANDWIDTH,
39 };
40 
41 static struct memory_locality *localities_types[4];
42 
43 struct target_cache {
44 	struct list_head node;
45 	struct node_cache_attrs cache_attrs;
46 };
47 
48 struct memory_target {
49 	struct list_head node;
50 	unsigned int memory_pxm;
51 	unsigned int processor_pxm;
52 	struct node_hmem_attrs hmem_attrs;
53 	struct list_head caches;
54 	struct node_cache_attrs cache_attrs;
55 	bool registered;
56 };
57 
58 struct memory_initiator {
59 	struct list_head node;
60 	unsigned int processor_pxm;
61 };
62 
63 struct memory_locality {
64 	struct list_head node;
65 	struct acpi_hmat_locality *hmat_loc;
66 };
67 
find_mem_initiator(unsigned int cpu_pxm)68 static struct memory_initiator *find_mem_initiator(unsigned int cpu_pxm)
69 {
70 	struct memory_initiator *initiator;
71 
72 	list_for_each_entry(initiator, &initiators, node)
73 		if (initiator->processor_pxm == cpu_pxm)
74 			return initiator;
75 	return NULL;
76 }
77 
find_mem_target(unsigned int mem_pxm)78 static struct memory_target *find_mem_target(unsigned int mem_pxm)
79 {
80 	struct memory_target *target;
81 
82 	list_for_each_entry(target, &targets, node)
83 		if (target->memory_pxm == mem_pxm)
84 			return target;
85 	return NULL;
86 }
87 
alloc_memory_initiator(unsigned int cpu_pxm)88 static __init void alloc_memory_initiator(unsigned int cpu_pxm)
89 {
90 	struct memory_initiator *initiator;
91 
92 	if (pxm_to_node(cpu_pxm) == NUMA_NO_NODE)
93 		return;
94 
95 	initiator = find_mem_initiator(cpu_pxm);
96 	if (initiator)
97 		return;
98 
99 	initiator = kzalloc(sizeof(*initiator), GFP_KERNEL);
100 	if (!initiator)
101 		return;
102 
103 	initiator->processor_pxm = cpu_pxm;
104 	list_add_tail(&initiator->node, &initiators);
105 }
106 
alloc_memory_target(unsigned int mem_pxm)107 static __init void alloc_memory_target(unsigned int mem_pxm)
108 {
109 	struct memory_target *target;
110 
111 	target = find_mem_target(mem_pxm);
112 	if (target)
113 		return;
114 
115 	target = kzalloc(sizeof(*target), GFP_KERNEL);
116 	if (!target)
117 		return;
118 
119 	target->memory_pxm = mem_pxm;
120 	target->processor_pxm = PXM_INVAL;
121 	list_add_tail(&target->node, &targets);
122 	INIT_LIST_HEAD(&target->caches);
123 }
124 
hmat_data_type(u8 type)125 static __init const char *hmat_data_type(u8 type)
126 {
127 	switch (type) {
128 	case ACPI_HMAT_ACCESS_LATENCY:
129 		return "Access Latency";
130 	case ACPI_HMAT_READ_LATENCY:
131 		return "Read Latency";
132 	case ACPI_HMAT_WRITE_LATENCY:
133 		return "Write Latency";
134 	case ACPI_HMAT_ACCESS_BANDWIDTH:
135 		return "Access Bandwidth";
136 	case ACPI_HMAT_READ_BANDWIDTH:
137 		return "Read Bandwidth";
138 	case ACPI_HMAT_WRITE_BANDWIDTH:
139 		return "Write Bandwidth";
140 	default:
141 		return "Reserved";
142 	}
143 }
144 
hmat_data_type_suffix(u8 type)145 static __init const char *hmat_data_type_suffix(u8 type)
146 {
147 	switch (type) {
148 	case ACPI_HMAT_ACCESS_LATENCY:
149 	case ACPI_HMAT_READ_LATENCY:
150 	case ACPI_HMAT_WRITE_LATENCY:
151 		return " nsec";
152 	case ACPI_HMAT_ACCESS_BANDWIDTH:
153 	case ACPI_HMAT_READ_BANDWIDTH:
154 	case ACPI_HMAT_WRITE_BANDWIDTH:
155 		return " MB/s";
156 	default:
157 		return "";
158 	}
159 }
160 
hmat_normalize(u16 entry,u64 base,u8 type)161 static u32 hmat_normalize(u16 entry, u64 base, u8 type)
162 {
163 	u32 value;
164 
165 	/*
166 	 * Check for invalid and overflow values
167 	 */
168 	if (entry == 0xffff || !entry)
169 		return 0;
170 	else if (base > (UINT_MAX / (entry)))
171 		return 0;
172 
173 	/*
174 	 * Divide by the base unit for version 1, convert latency from
175 	 * picosenonds to nanoseconds if revision 2.
176 	 */
177 	value = entry * base;
178 	if (hmat_revision == 1) {
179 		if (value < 10)
180 			return 0;
181 		value = DIV_ROUND_UP(value, 10);
182 	} else if (hmat_revision == 2) {
183 		switch (type) {
184 		case ACPI_HMAT_ACCESS_LATENCY:
185 		case ACPI_HMAT_READ_LATENCY:
186 		case ACPI_HMAT_WRITE_LATENCY:
187 			value = DIV_ROUND_UP(value, 1000);
188 			break;
189 		default:
190 			break;
191 		}
192 	}
193 	return value;
194 }
195 
hmat_update_target_access(struct memory_target * target,u8 type,u32 value)196 static void hmat_update_target_access(struct memory_target *target,
197 					     u8 type, u32 value)
198 {
199 	switch (type) {
200 	case ACPI_HMAT_ACCESS_LATENCY:
201 		target->hmem_attrs.read_latency = value;
202 		target->hmem_attrs.write_latency = value;
203 		break;
204 	case ACPI_HMAT_READ_LATENCY:
205 		target->hmem_attrs.read_latency = value;
206 		break;
207 	case ACPI_HMAT_WRITE_LATENCY:
208 		target->hmem_attrs.write_latency = value;
209 		break;
210 	case ACPI_HMAT_ACCESS_BANDWIDTH:
211 		target->hmem_attrs.read_bandwidth = value;
212 		target->hmem_attrs.write_bandwidth = value;
213 		break;
214 	case ACPI_HMAT_READ_BANDWIDTH:
215 		target->hmem_attrs.read_bandwidth = value;
216 		break;
217 	case ACPI_HMAT_WRITE_BANDWIDTH:
218 		target->hmem_attrs.write_bandwidth = value;
219 		break;
220 	default:
221 		break;
222 	}
223 }
224 
hmat_add_locality(struct acpi_hmat_locality * hmat_loc)225 static __init void hmat_add_locality(struct acpi_hmat_locality *hmat_loc)
226 {
227 	struct memory_locality *loc;
228 
229 	loc = kzalloc(sizeof(*loc), GFP_KERNEL);
230 	if (!loc) {
231 		pr_notice_once("Failed to allocate HMAT locality\n");
232 		return;
233 	}
234 
235 	loc->hmat_loc = hmat_loc;
236 	list_add_tail(&loc->node, &localities);
237 
238 	switch (hmat_loc->data_type) {
239 	case ACPI_HMAT_ACCESS_LATENCY:
240 		localities_types[READ_LATENCY] = loc;
241 		localities_types[WRITE_LATENCY] = loc;
242 		break;
243 	case ACPI_HMAT_READ_LATENCY:
244 		localities_types[READ_LATENCY] = loc;
245 		break;
246 	case ACPI_HMAT_WRITE_LATENCY:
247 		localities_types[WRITE_LATENCY] = loc;
248 		break;
249 	case ACPI_HMAT_ACCESS_BANDWIDTH:
250 		localities_types[READ_BANDWIDTH] = loc;
251 		localities_types[WRITE_BANDWIDTH] = loc;
252 		break;
253 	case ACPI_HMAT_READ_BANDWIDTH:
254 		localities_types[READ_BANDWIDTH] = loc;
255 		break;
256 	case ACPI_HMAT_WRITE_BANDWIDTH:
257 		localities_types[WRITE_BANDWIDTH] = loc;
258 		break;
259 	default:
260 		break;
261 	}
262 }
263 
hmat_parse_locality(union acpi_subtable_headers * header,const unsigned long end)264 static __init int hmat_parse_locality(union acpi_subtable_headers *header,
265 				      const unsigned long end)
266 {
267 	struct acpi_hmat_locality *hmat_loc = (void *)header;
268 	struct memory_target *target;
269 	unsigned int init, targ, total_size, ipds, tpds;
270 	u32 *inits, *targs, value;
271 	u16 *entries;
272 	u8 type, mem_hier;
273 
274 	if (hmat_loc->header.length < sizeof(*hmat_loc)) {
275 		pr_notice("HMAT: Unexpected locality header length: %d\n",
276 			 hmat_loc->header.length);
277 		return -EINVAL;
278 	}
279 
280 	type = hmat_loc->data_type;
281 	mem_hier = hmat_loc->flags & ACPI_HMAT_MEMORY_HIERARCHY;
282 	ipds = hmat_loc->number_of_initiator_Pds;
283 	tpds = hmat_loc->number_of_target_Pds;
284 	total_size = sizeof(*hmat_loc) + sizeof(*entries) * ipds * tpds +
285 		     sizeof(*inits) * ipds + sizeof(*targs) * tpds;
286 	if (hmat_loc->header.length < total_size) {
287 		pr_notice("HMAT: Unexpected locality header length:%d, minimum required:%d\n",
288 			 hmat_loc->header.length, total_size);
289 		return -EINVAL;
290 	}
291 
292 	pr_info("HMAT: Locality: Flags:%02x Type:%s Initiator Domains:%d Target Domains:%d Base:%lld\n",
293 		hmat_loc->flags, hmat_data_type(type), ipds, tpds,
294 		hmat_loc->entry_base_unit);
295 
296 	inits = (u32 *)(hmat_loc + 1);
297 	targs = inits + ipds;
298 	entries = (u16 *)(targs + tpds);
299 	for (init = 0; init < ipds; init++) {
300 		alloc_memory_initiator(inits[init]);
301 		for (targ = 0; targ < tpds; targ++) {
302 			value = hmat_normalize(entries[init * tpds + targ],
303 					       hmat_loc->entry_base_unit,
304 					       type);
305 			pr_info("  Initiator-Target[%d-%d]:%d%s\n",
306 				inits[init], targs[targ], value,
307 				hmat_data_type_suffix(type));
308 
309 			if (mem_hier == ACPI_HMAT_MEMORY) {
310 				target = find_mem_target(targs[targ]);
311 				if (target && target->processor_pxm == inits[init])
312 					hmat_update_target_access(target, type, value);
313 			}
314 		}
315 	}
316 
317 	if (mem_hier == ACPI_HMAT_MEMORY)
318 		hmat_add_locality(hmat_loc);
319 
320 	return 0;
321 }
322 
hmat_parse_cache(union acpi_subtable_headers * header,const unsigned long end)323 static __init int hmat_parse_cache(union acpi_subtable_headers *header,
324 				   const unsigned long end)
325 {
326 	struct acpi_hmat_cache *cache = (void *)header;
327 	struct memory_target *target;
328 	struct target_cache *tcache;
329 	u32 attrs;
330 
331 	if (cache->header.length < sizeof(*cache)) {
332 		pr_notice("HMAT: Unexpected cache header length: %d\n",
333 			 cache->header.length);
334 		return -EINVAL;
335 	}
336 
337 	attrs = cache->cache_attributes;
338 	pr_info("HMAT: Cache: Domain:%d Size:%llu Attrs:%08x SMBIOS Handles:%d\n",
339 		cache->memory_PD, cache->cache_size, attrs,
340 		cache->number_of_SMBIOShandles);
341 
342 	target = find_mem_target(cache->memory_PD);
343 	if (!target)
344 		return 0;
345 
346 	tcache = kzalloc(sizeof(*tcache), GFP_KERNEL);
347 	if (!tcache) {
348 		pr_notice_once("Failed to allocate HMAT cache info\n");
349 		return 0;
350 	}
351 
352 	tcache->cache_attrs.size = cache->cache_size;
353 	tcache->cache_attrs.level = (attrs & ACPI_HMAT_CACHE_LEVEL) >> 4;
354 	tcache->cache_attrs.line_size = (attrs & ACPI_HMAT_CACHE_LINE_SIZE) >> 16;
355 
356 	switch ((attrs & ACPI_HMAT_CACHE_ASSOCIATIVITY) >> 8) {
357 	case ACPI_HMAT_CA_DIRECT_MAPPED:
358 		tcache->cache_attrs.indexing = NODE_CACHE_DIRECT_MAP;
359 		break;
360 	case ACPI_HMAT_CA_COMPLEX_CACHE_INDEXING:
361 		tcache->cache_attrs.indexing = NODE_CACHE_INDEXED;
362 		break;
363 	case ACPI_HMAT_CA_NONE:
364 	default:
365 		tcache->cache_attrs.indexing = NODE_CACHE_OTHER;
366 		break;
367 	}
368 
369 	switch ((attrs & ACPI_HMAT_WRITE_POLICY) >> 12) {
370 	case ACPI_HMAT_CP_WB:
371 		tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_BACK;
372 		break;
373 	case ACPI_HMAT_CP_WT:
374 		tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_THROUGH;
375 		break;
376 	case ACPI_HMAT_CP_NONE:
377 	default:
378 		tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_OTHER;
379 		break;
380 	}
381 	list_add_tail(&tcache->node, &target->caches);
382 
383 	return 0;
384 }
385 
hmat_parse_proximity_domain(union acpi_subtable_headers * header,const unsigned long end)386 static int __init hmat_parse_proximity_domain(union acpi_subtable_headers *header,
387 					      const unsigned long end)
388 {
389 	struct acpi_hmat_proximity_domain *p = (void *)header;
390 	struct memory_target *target = NULL;
391 
392 	if (p->header.length != sizeof(*p)) {
393 		pr_notice("HMAT: Unexpected address range header length: %d\n",
394 			 p->header.length);
395 		return -EINVAL;
396 	}
397 
398 	if (hmat_revision == 1)
399 		pr_info("HMAT: Memory (%#llx length %#llx) Flags:%04x Processor Domain:%d Memory Domain:%d\n",
400 			p->reserved3, p->reserved4, p->flags, p->processor_PD,
401 			p->memory_PD);
402 	else
403 		pr_info("HMAT: Memory Flags:%04x Processor Domain:%d Memory Domain:%d\n",
404 			p->flags, p->processor_PD, p->memory_PD);
405 
406 	if (p->flags & ACPI_HMAT_MEMORY_PD_VALID && hmat_revision == 1) {
407 		target = find_mem_target(p->memory_PD);
408 		if (!target) {
409 			pr_debug("HMAT: Memory Domain missing from SRAT\n");
410 			return -EINVAL;
411 		}
412 	}
413 	if (target && p->flags & ACPI_HMAT_PROCESSOR_PD_VALID) {
414 		int p_node = pxm_to_node(p->processor_PD);
415 
416 		if (p_node == NUMA_NO_NODE) {
417 			pr_debug("HMAT: Invalid Processor Domain\n");
418 			return -EINVAL;
419 		}
420 		target->processor_pxm = p_node;
421 	}
422 
423 	return 0;
424 }
425 
hmat_parse_subtable(union acpi_subtable_headers * header,const unsigned long end)426 static int __init hmat_parse_subtable(union acpi_subtable_headers *header,
427 				      const unsigned long end)
428 {
429 	struct acpi_hmat_structure *hdr = (void *)header;
430 
431 	if (!hdr)
432 		return -EINVAL;
433 
434 	switch (hdr->type) {
435 	case ACPI_HMAT_TYPE_PROXIMITY:
436 		return hmat_parse_proximity_domain(header, end);
437 	case ACPI_HMAT_TYPE_LOCALITY:
438 		return hmat_parse_locality(header, end);
439 	case ACPI_HMAT_TYPE_CACHE:
440 		return hmat_parse_cache(header, end);
441 	default:
442 		return -EINVAL;
443 	}
444 }
445 
srat_parse_mem_affinity(union acpi_subtable_headers * header,const unsigned long end)446 static __init int srat_parse_mem_affinity(union acpi_subtable_headers *header,
447 					  const unsigned long end)
448 {
449 	struct acpi_srat_mem_affinity *ma = (void *)header;
450 
451 	if (!ma)
452 		return -EINVAL;
453 	if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
454 		return 0;
455 	alloc_memory_target(ma->proximity_domain);
456 	return 0;
457 }
458 
hmat_initiator_perf(struct memory_target * target,struct memory_initiator * initiator,struct acpi_hmat_locality * hmat_loc)459 static u32 hmat_initiator_perf(struct memory_target *target,
460 			       struct memory_initiator *initiator,
461 			       struct acpi_hmat_locality *hmat_loc)
462 {
463 	unsigned int ipds, tpds, i, idx = 0, tdx = 0;
464 	u32 *inits, *targs;
465 	u16 *entries;
466 
467 	ipds = hmat_loc->number_of_initiator_Pds;
468 	tpds = hmat_loc->number_of_target_Pds;
469 	inits = (u32 *)(hmat_loc + 1);
470 	targs = inits + ipds;
471 	entries = (u16 *)(targs + tpds);
472 
473 	for (i = 0; i < ipds; i++) {
474 		if (inits[i] == initiator->processor_pxm) {
475 			idx = i;
476 			break;
477 		}
478 	}
479 
480 	if (i == ipds)
481 		return 0;
482 
483 	for (i = 0; i < tpds; i++) {
484 		if (targs[i] == target->memory_pxm) {
485 			tdx = i;
486 			break;
487 		}
488 	}
489 	if (i == tpds)
490 		return 0;
491 
492 	return hmat_normalize(entries[idx * tpds + tdx],
493 			      hmat_loc->entry_base_unit,
494 			      hmat_loc->data_type);
495 }
496 
hmat_update_best(u8 type,u32 value,u32 * best)497 static bool hmat_update_best(u8 type, u32 value, u32 *best)
498 {
499 	bool updated = false;
500 
501 	if (!value)
502 		return false;
503 
504 	switch (type) {
505 	case ACPI_HMAT_ACCESS_LATENCY:
506 	case ACPI_HMAT_READ_LATENCY:
507 	case ACPI_HMAT_WRITE_LATENCY:
508 		if (!*best || *best > value) {
509 			*best = value;
510 			updated = true;
511 		}
512 		break;
513 	case ACPI_HMAT_ACCESS_BANDWIDTH:
514 	case ACPI_HMAT_READ_BANDWIDTH:
515 	case ACPI_HMAT_WRITE_BANDWIDTH:
516 		if (!*best || *best < value) {
517 			*best = value;
518 			updated = true;
519 		}
520 		break;
521 	}
522 
523 	return updated;
524 }
525 
initiator_cmp(void * priv,struct list_head * a,struct list_head * b)526 static int initiator_cmp(void *priv, struct list_head *a, struct list_head *b)
527 {
528 	struct memory_initiator *ia;
529 	struct memory_initiator *ib;
530 	unsigned long *p_nodes = priv;
531 
532 	ia = list_entry(a, struct memory_initiator, node);
533 	ib = list_entry(b, struct memory_initiator, node);
534 
535 	set_bit(ia->processor_pxm, p_nodes);
536 	set_bit(ib->processor_pxm, p_nodes);
537 
538 	return ia->processor_pxm - ib->processor_pxm;
539 }
540 
hmat_register_target_initiators(struct memory_target * target)541 static void hmat_register_target_initiators(struct memory_target *target)
542 {
543 	static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
544 	struct memory_initiator *initiator;
545 	unsigned int mem_nid, cpu_nid;
546 	struct memory_locality *loc = NULL;
547 	u32 best = 0;
548 	int i;
549 
550 	mem_nid = pxm_to_node(target->memory_pxm);
551 	/*
552 	 * If the Address Range Structure provides a local processor pxm, link
553 	 * only that one. Otherwise, find the best performance attributes and
554 	 * register all initiators that match.
555 	 */
556 	if (target->processor_pxm != PXM_INVAL) {
557 		cpu_nid = pxm_to_node(target->processor_pxm);
558 		register_memory_node_under_compute_node(mem_nid, cpu_nid, 0);
559 		return;
560 	}
561 
562 	if (list_empty(&localities))
563 		return;
564 
565 	/*
566 	 * We need the initiator list sorted so we can use bitmap_clear for
567 	 * previously set initiators when we find a better memory accessor.
568 	 * We'll also use the sorting to prime the candidate nodes with known
569 	 * initiators.
570 	 */
571 	bitmap_zero(p_nodes, MAX_NUMNODES);
572 	list_sort(p_nodes, &initiators, initiator_cmp);
573 	for (i = WRITE_LATENCY; i <= READ_BANDWIDTH; i++) {
574 		loc = localities_types[i];
575 		if (!loc)
576 			continue;
577 
578 		best = 0;
579 		list_for_each_entry(initiator, &initiators, node) {
580 			u32 value;
581 
582 			if (!test_bit(initiator->processor_pxm, p_nodes))
583 				continue;
584 
585 			value = hmat_initiator_perf(target, initiator, loc->hmat_loc);
586 			if (hmat_update_best(loc->hmat_loc->data_type, value, &best))
587 				bitmap_clear(p_nodes, 0, initiator->processor_pxm);
588 			if (value != best)
589 				clear_bit(initiator->processor_pxm, p_nodes);
590 		}
591 		if (best)
592 			hmat_update_target_access(target, loc->hmat_loc->data_type, best);
593 	}
594 
595 	for_each_set_bit(i, p_nodes, MAX_NUMNODES) {
596 		cpu_nid = pxm_to_node(i);
597 		register_memory_node_under_compute_node(mem_nid, cpu_nid, 0);
598 	}
599 }
600 
hmat_register_target_cache(struct memory_target * target)601 static void hmat_register_target_cache(struct memory_target *target)
602 {
603 	unsigned mem_nid = pxm_to_node(target->memory_pxm);
604 	struct target_cache *tcache;
605 
606 	list_for_each_entry(tcache, &target->caches, node)
607 		node_add_cache(mem_nid, &tcache->cache_attrs);
608 }
609 
hmat_register_target_perf(struct memory_target * target)610 static void hmat_register_target_perf(struct memory_target *target)
611 {
612 	unsigned mem_nid = pxm_to_node(target->memory_pxm);
613 	node_set_perf_attrs(mem_nid, &target->hmem_attrs, 0);
614 }
615 
hmat_register_target(struct memory_target * target)616 static void hmat_register_target(struct memory_target *target)
617 {
618 	int nid = pxm_to_node(target->memory_pxm);
619 
620 	/*
621 	 * Skip offline nodes. This can happen when memory
622 	 * marked EFI_MEMORY_SP, "specific purpose", is applied
623 	 * to all the memory in a promixity domain leading to
624 	 * the node being marked offline / unplugged, or if
625 	 * memory-only "hotplug" node is offline.
626 	 */
627 	if (nid == NUMA_NO_NODE || !node_online(nid))
628 		return;
629 
630 	mutex_lock(&target_lock);
631 	if (!target->registered) {
632 		hmat_register_target_initiators(target);
633 		hmat_register_target_cache(target);
634 		hmat_register_target_perf(target);
635 		target->registered = true;
636 	}
637 	mutex_unlock(&target_lock);
638 }
639 
hmat_register_targets(void)640 static void hmat_register_targets(void)
641 {
642 	struct memory_target *target;
643 
644 	list_for_each_entry(target, &targets, node)
645 		hmat_register_target(target);
646 }
647 
hmat_callback(struct notifier_block * self,unsigned long action,void * arg)648 static int hmat_callback(struct notifier_block *self,
649 			 unsigned long action, void *arg)
650 {
651 	struct memory_target *target;
652 	struct memory_notify *mnb = arg;
653 	int pxm, nid = mnb->status_change_nid;
654 
655 	if (nid == NUMA_NO_NODE || action != MEM_ONLINE)
656 		return NOTIFY_OK;
657 
658 	pxm = node_to_pxm(nid);
659 	target = find_mem_target(pxm);
660 	if (!target)
661 		return NOTIFY_OK;
662 
663 	hmat_register_target(target);
664 	return NOTIFY_OK;
665 }
666 
667 static struct notifier_block hmat_callback_nb = {
668 	.notifier_call = hmat_callback,
669 	.priority = 2,
670 };
671 
hmat_free_structures(void)672 static __init void hmat_free_structures(void)
673 {
674 	struct memory_target *target, *tnext;
675 	struct memory_locality *loc, *lnext;
676 	struct memory_initiator *initiator, *inext;
677 	struct target_cache *tcache, *cnext;
678 
679 	list_for_each_entry_safe(target, tnext, &targets, node) {
680 		list_for_each_entry_safe(tcache, cnext, &target->caches, node) {
681 			list_del(&tcache->node);
682 			kfree(tcache);
683 		}
684 		list_del(&target->node);
685 		kfree(target);
686 	}
687 
688 	list_for_each_entry_safe(initiator, inext, &initiators, node) {
689 		list_del(&initiator->node);
690 		kfree(initiator);
691 	}
692 
693 	list_for_each_entry_safe(loc, lnext, &localities, node) {
694 		list_del(&loc->node);
695 		kfree(loc);
696 	}
697 }
698 
hmat_init(void)699 static __init int hmat_init(void)
700 {
701 	struct acpi_table_header *tbl;
702 	enum acpi_hmat_type i;
703 	acpi_status status;
704 
705 	if (srat_disabled())
706 		return 0;
707 
708 	status = acpi_get_table(ACPI_SIG_SRAT, 0, &tbl);
709 	if (ACPI_FAILURE(status))
710 		return 0;
711 
712 	if (acpi_table_parse_entries(ACPI_SIG_SRAT,
713 				sizeof(struct acpi_table_srat),
714 				ACPI_SRAT_TYPE_MEMORY_AFFINITY,
715 				srat_parse_mem_affinity, 0) < 0)
716 		goto out_put;
717 	acpi_put_table(tbl);
718 
719 	status = acpi_get_table(ACPI_SIG_HMAT, 0, &tbl);
720 	if (ACPI_FAILURE(status))
721 		goto out_put;
722 
723 	hmat_revision = tbl->revision;
724 	switch (hmat_revision) {
725 	case 1:
726 	case 2:
727 		break;
728 	default:
729 		pr_notice("Ignoring HMAT: Unknown revision:%d\n", hmat_revision);
730 		goto out_put;
731 	}
732 
733 	for (i = ACPI_HMAT_TYPE_PROXIMITY; i < ACPI_HMAT_TYPE_RESERVED; i++) {
734 		if (acpi_table_parse_entries(ACPI_SIG_HMAT,
735 					     sizeof(struct acpi_table_hmat), i,
736 					     hmat_parse_subtable, 0) < 0) {
737 			pr_notice("Ignoring HMAT: Invalid table");
738 			goto out_put;
739 		}
740 	}
741 	hmat_register_targets();
742 
743 	/* Keep the table and structures if the notifier may use them */
744 	if (!register_hotmemory_notifier(&hmat_callback_nb))
745 		return 0;
746 out_put:
747 	hmat_free_structures();
748 	acpi_put_table(tbl);
749 	return 0;
750 }
751 subsys_initcall(hmat_init);
752