xref: /linux/drivers/acpi/nfit/core.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  */
13 #include <linux/list_sort.h>
14 #include <linux/libnvdimm.h>
15 #include <linux/module.h>
16 #include <linux/mutex.h>
17 #include <linux/ndctl.h>
18 #include <linux/sysfs.h>
19 #include <linux/delay.h>
20 #include <linux/list.h>
21 #include <linux/acpi.h>
22 #include <linux/sort.h>
23 #include <linux/pmem.h>
24 #include <linux/io.h>
25 #include <linux/nd.h>
26 #include <asm/cacheflush.h>
27 #include "nfit.h"
28 
29 /*
30  * For readq() and writeq() on 32-bit builds, the hi-lo, lo-hi order is
31  * irrelevant.
32  */
33 #include <linux/io-64-nonatomic-hi-lo.h>
34 
35 static bool force_enable_dimms;
36 module_param(force_enable_dimms, bool, S_IRUGO|S_IWUSR);
37 MODULE_PARM_DESC(force_enable_dimms, "Ignore _STA (ACPI DIMM device) status");
38 
39 static unsigned int scrub_timeout = NFIT_ARS_TIMEOUT;
40 module_param(scrub_timeout, uint, S_IRUGO|S_IWUSR);
41 MODULE_PARM_DESC(scrub_timeout, "Initial scrub timeout in seconds");
42 
43 /* after three payloads of overflow, it's dead jim */
44 static unsigned int scrub_overflow_abort = 3;
45 module_param(scrub_overflow_abort, uint, S_IRUGO|S_IWUSR);
46 MODULE_PARM_DESC(scrub_overflow_abort,
47 		"Number of times we overflow ARS results before abort");
48 
49 static bool disable_vendor_specific;
50 module_param(disable_vendor_specific, bool, S_IRUGO);
51 MODULE_PARM_DESC(disable_vendor_specific,
52 		"Limit commands to the publicly specified set\n");
53 
54 LIST_HEAD(acpi_descs);
55 DEFINE_MUTEX(acpi_desc_lock);
56 
57 static struct workqueue_struct *nfit_wq;
58 
59 struct nfit_table_prev {
60 	struct list_head spas;
61 	struct list_head memdevs;
62 	struct list_head dcrs;
63 	struct list_head bdws;
64 	struct list_head idts;
65 	struct list_head flushes;
66 };
67 
68 static u8 nfit_uuid[NFIT_UUID_MAX][16];
69 
70 const u8 *to_nfit_uuid(enum nfit_uuids id)
71 {
72 	return nfit_uuid[id];
73 }
74 EXPORT_SYMBOL(to_nfit_uuid);
75 
76 static struct acpi_nfit_desc *to_acpi_nfit_desc(
77 		struct nvdimm_bus_descriptor *nd_desc)
78 {
79 	return container_of(nd_desc, struct acpi_nfit_desc, nd_desc);
80 }
81 
82 static struct acpi_device *to_acpi_dev(struct acpi_nfit_desc *acpi_desc)
83 {
84 	struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
85 
86 	/*
87 	 * If provider == 'ACPI.NFIT' we can assume 'dev' is a struct
88 	 * acpi_device.
89 	 */
90 	if (!nd_desc->provider_name
91 			|| strcmp(nd_desc->provider_name, "ACPI.NFIT") != 0)
92 		return NULL;
93 
94 	return to_acpi_device(acpi_desc->dev);
95 }
96 
97 static int xlat_bus_status(void *buf, unsigned int cmd, u32 status)
98 {
99 	struct nd_cmd_clear_error *clear_err;
100 	struct nd_cmd_ars_status *ars_status;
101 	u16 flags;
102 
103 	switch (cmd) {
104 	case ND_CMD_ARS_CAP:
105 		if ((status & 0xffff) == NFIT_ARS_CAP_NONE)
106 			return -ENOTTY;
107 
108 		/* Command failed */
109 		if (status & 0xffff)
110 			return -EIO;
111 
112 		/* No supported scan types for this range */
113 		flags = ND_ARS_PERSISTENT | ND_ARS_VOLATILE;
114 		if ((status >> 16 & flags) == 0)
115 			return -ENOTTY;
116 		return 0;
117 	case ND_CMD_ARS_START:
118 		/* ARS is in progress */
119 		if ((status & 0xffff) == NFIT_ARS_START_BUSY)
120 			return -EBUSY;
121 
122 		/* Command failed */
123 		if (status & 0xffff)
124 			return -EIO;
125 		return 0;
126 	case ND_CMD_ARS_STATUS:
127 		ars_status = buf;
128 		/* Command failed */
129 		if (status & 0xffff)
130 			return -EIO;
131 		/* Check extended status (Upper two bytes) */
132 		if (status == NFIT_ARS_STATUS_DONE)
133 			return 0;
134 
135 		/* ARS is in progress */
136 		if (status == NFIT_ARS_STATUS_BUSY)
137 			return -EBUSY;
138 
139 		/* No ARS performed for the current boot */
140 		if (status == NFIT_ARS_STATUS_NONE)
141 			return -EAGAIN;
142 
143 		/*
144 		 * ARS interrupted, either we overflowed or some other
145 		 * agent wants the scan to stop.  If we didn't overflow
146 		 * then just continue with the returned results.
147 		 */
148 		if (status == NFIT_ARS_STATUS_INTR) {
149 			if (ars_status->out_length >= 40 && (ars_status->flags
150 						& NFIT_ARS_F_OVERFLOW))
151 				return -ENOSPC;
152 			return 0;
153 		}
154 
155 		/* Unknown status */
156 		if (status >> 16)
157 			return -EIO;
158 		return 0;
159 	case ND_CMD_CLEAR_ERROR:
160 		clear_err = buf;
161 		if (status & 0xffff)
162 			return -EIO;
163 		if (!clear_err->cleared)
164 			return -EIO;
165 		if (clear_err->length > clear_err->cleared)
166 			return clear_err->cleared;
167 		return 0;
168 	default:
169 		break;
170 	}
171 
172 	/* all other non-zero status results in an error */
173 	if (status)
174 		return -EIO;
175 	return 0;
176 }
177 
178 static int xlat_status(struct nvdimm *nvdimm, void *buf, unsigned int cmd,
179 		u32 status)
180 {
181 	if (!nvdimm)
182 		return xlat_bus_status(buf, cmd, status);
183 	if (status)
184 		return -EIO;
185 	return 0;
186 }
187 
188 int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
189 		unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc)
190 {
191 	struct acpi_nfit_desc *acpi_desc = to_acpi_nfit_desc(nd_desc);
192 	union acpi_object in_obj, in_buf, *out_obj;
193 	const struct nd_cmd_desc *desc = NULL;
194 	struct device *dev = acpi_desc->dev;
195 	struct nd_cmd_pkg *call_pkg = NULL;
196 	const char *cmd_name, *dimm_name;
197 	unsigned long cmd_mask, dsm_mask;
198 	u32 offset, fw_status = 0;
199 	acpi_handle handle;
200 	unsigned int func;
201 	const u8 *uuid;
202 	int rc, i;
203 
204 	func = cmd;
205 	if (cmd == ND_CMD_CALL) {
206 		call_pkg = buf;
207 		func = call_pkg->nd_command;
208 	}
209 
210 	if (nvdimm) {
211 		struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
212 		struct acpi_device *adev = nfit_mem->adev;
213 
214 		if (!adev)
215 			return -ENOTTY;
216 		if (call_pkg && nfit_mem->family != call_pkg->nd_family)
217 			return -ENOTTY;
218 
219 		dimm_name = nvdimm_name(nvdimm);
220 		cmd_name = nvdimm_cmd_name(cmd);
221 		cmd_mask = nvdimm_cmd_mask(nvdimm);
222 		dsm_mask = nfit_mem->dsm_mask;
223 		desc = nd_cmd_dimm_desc(cmd);
224 		uuid = to_nfit_uuid(nfit_mem->family);
225 		handle = adev->handle;
226 	} else {
227 		struct acpi_device *adev = to_acpi_dev(acpi_desc);
228 
229 		cmd_name = nvdimm_bus_cmd_name(cmd);
230 		cmd_mask = nd_desc->cmd_mask;
231 		dsm_mask = cmd_mask;
232 		desc = nd_cmd_bus_desc(cmd);
233 		uuid = to_nfit_uuid(NFIT_DEV_BUS);
234 		handle = adev->handle;
235 		dimm_name = "bus";
236 	}
237 
238 	if (!desc || (cmd && (desc->out_num + desc->in_num == 0)))
239 		return -ENOTTY;
240 
241 	if (!test_bit(cmd, &cmd_mask) || !test_bit(func, &dsm_mask))
242 		return -ENOTTY;
243 
244 	in_obj.type = ACPI_TYPE_PACKAGE;
245 	in_obj.package.count = 1;
246 	in_obj.package.elements = &in_buf;
247 	in_buf.type = ACPI_TYPE_BUFFER;
248 	in_buf.buffer.pointer = buf;
249 	in_buf.buffer.length = 0;
250 
251 	/* libnvdimm has already validated the input envelope */
252 	for (i = 0; i < desc->in_num; i++)
253 		in_buf.buffer.length += nd_cmd_in_size(nvdimm, cmd, desc,
254 				i, buf);
255 
256 	if (call_pkg) {
257 		/* skip over package wrapper */
258 		in_buf.buffer.pointer = (void *) &call_pkg->nd_payload;
259 		in_buf.buffer.length = call_pkg->nd_size_in;
260 	}
261 
262 	if (IS_ENABLED(CONFIG_ACPI_NFIT_DEBUG)) {
263 		dev_dbg(dev, "%s:%s cmd: %d: func: %d input length: %d\n",
264 				__func__, dimm_name, cmd, func,
265 				in_buf.buffer.length);
266 		print_hex_dump_debug("nvdimm in  ", DUMP_PREFIX_OFFSET, 4, 4,
267 			in_buf.buffer.pointer,
268 			min_t(u32, 256, in_buf.buffer.length), true);
269 	}
270 
271 	out_obj = acpi_evaluate_dsm(handle, uuid, 1, func, &in_obj);
272 	if (!out_obj) {
273 		dev_dbg(dev, "%s:%s _DSM failed cmd: %s\n", __func__, dimm_name,
274 				cmd_name);
275 		return -EINVAL;
276 	}
277 
278 	if (call_pkg) {
279 		call_pkg->nd_fw_size = out_obj->buffer.length;
280 		memcpy(call_pkg->nd_payload + call_pkg->nd_size_in,
281 			out_obj->buffer.pointer,
282 			min(call_pkg->nd_fw_size, call_pkg->nd_size_out));
283 
284 		ACPI_FREE(out_obj);
285 		/*
286 		 * Need to support FW function w/o known size in advance.
287 		 * Caller can determine required size based upon nd_fw_size.
288 		 * If we return an error (like elsewhere) then caller wouldn't
289 		 * be able to rely upon data returned to make calculation.
290 		 */
291 		return 0;
292 	}
293 
294 	if (out_obj->package.type != ACPI_TYPE_BUFFER) {
295 		dev_dbg(dev, "%s:%s unexpected output object type cmd: %s type: %d\n",
296 				__func__, dimm_name, cmd_name, out_obj->type);
297 		rc = -EINVAL;
298 		goto out;
299 	}
300 
301 	if (IS_ENABLED(CONFIG_ACPI_NFIT_DEBUG)) {
302 		dev_dbg(dev, "%s:%s cmd: %s output length: %d\n", __func__,
303 				dimm_name, cmd_name, out_obj->buffer.length);
304 		print_hex_dump_debug(cmd_name, DUMP_PREFIX_OFFSET, 4,
305 				4, out_obj->buffer.pointer, min_t(u32, 128,
306 					out_obj->buffer.length), true);
307 	}
308 
309 	for (i = 0, offset = 0; i < desc->out_num; i++) {
310 		u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i, buf,
311 				(u32 *) out_obj->buffer.pointer,
312 				out_obj->buffer.length - offset);
313 
314 		if (offset + out_size > out_obj->buffer.length) {
315 			dev_dbg(dev, "%s:%s output object underflow cmd: %s field: %d\n",
316 					__func__, dimm_name, cmd_name, i);
317 			break;
318 		}
319 
320 		if (in_buf.buffer.length + offset + out_size > buf_len) {
321 			dev_dbg(dev, "%s:%s output overrun cmd: %s field: %d\n",
322 					__func__, dimm_name, cmd_name, i);
323 			rc = -ENXIO;
324 			goto out;
325 		}
326 		memcpy(buf + in_buf.buffer.length + offset,
327 				out_obj->buffer.pointer + offset, out_size);
328 		offset += out_size;
329 	}
330 
331 	/*
332 	 * Set fw_status for all the commands with a known format to be
333 	 * later interpreted by xlat_status().
334 	 */
335 	if (i >= 1 && ((cmd >= ND_CMD_ARS_CAP && cmd <= ND_CMD_CLEAR_ERROR)
336 			|| (cmd >= ND_CMD_SMART && cmd <= ND_CMD_VENDOR)))
337 		fw_status = *(u32 *) out_obj->buffer.pointer;
338 
339 	if (offset + in_buf.buffer.length < buf_len) {
340 		if (i >= 1) {
341 			/*
342 			 * status valid, return the number of bytes left
343 			 * unfilled in the output buffer
344 			 */
345 			rc = buf_len - offset - in_buf.buffer.length;
346 			if (cmd_rc)
347 				*cmd_rc = xlat_status(nvdimm, buf, cmd,
348 						fw_status);
349 		} else {
350 			dev_err(dev, "%s:%s underrun cmd: %s buf_len: %d out_len: %d\n",
351 					__func__, dimm_name, cmd_name, buf_len,
352 					offset);
353 			rc = -ENXIO;
354 		}
355 	} else {
356 		rc = 0;
357 		if (cmd_rc)
358 			*cmd_rc = xlat_status(nvdimm, buf, cmd, fw_status);
359 	}
360 
361  out:
362 	ACPI_FREE(out_obj);
363 
364 	return rc;
365 }
366 EXPORT_SYMBOL_GPL(acpi_nfit_ctl);
367 
368 static const char *spa_type_name(u16 type)
369 {
370 	static const char *to_name[] = {
371 		[NFIT_SPA_VOLATILE] = "volatile",
372 		[NFIT_SPA_PM] = "pmem",
373 		[NFIT_SPA_DCR] = "dimm-control-region",
374 		[NFIT_SPA_BDW] = "block-data-window",
375 		[NFIT_SPA_VDISK] = "volatile-disk",
376 		[NFIT_SPA_VCD] = "volatile-cd",
377 		[NFIT_SPA_PDISK] = "persistent-disk",
378 		[NFIT_SPA_PCD] = "persistent-cd",
379 
380 	};
381 
382 	if (type > NFIT_SPA_PCD)
383 		return "unknown";
384 
385 	return to_name[type];
386 }
387 
388 int nfit_spa_type(struct acpi_nfit_system_address *spa)
389 {
390 	int i;
391 
392 	for (i = 0; i < NFIT_UUID_MAX; i++)
393 		if (memcmp(to_nfit_uuid(i), spa->range_guid, 16) == 0)
394 			return i;
395 	return -1;
396 }
397 
398 static bool add_spa(struct acpi_nfit_desc *acpi_desc,
399 		struct nfit_table_prev *prev,
400 		struct acpi_nfit_system_address *spa)
401 {
402 	struct device *dev = acpi_desc->dev;
403 	struct nfit_spa *nfit_spa;
404 
405 	if (spa->header.length != sizeof(*spa))
406 		return false;
407 
408 	list_for_each_entry(nfit_spa, &prev->spas, list) {
409 		if (memcmp(nfit_spa->spa, spa, sizeof(*spa)) == 0) {
410 			list_move_tail(&nfit_spa->list, &acpi_desc->spas);
411 			return true;
412 		}
413 	}
414 
415 	nfit_spa = devm_kzalloc(dev, sizeof(*nfit_spa) + sizeof(*spa),
416 			GFP_KERNEL);
417 	if (!nfit_spa)
418 		return false;
419 	INIT_LIST_HEAD(&nfit_spa->list);
420 	memcpy(nfit_spa->spa, spa, sizeof(*spa));
421 	list_add_tail(&nfit_spa->list, &acpi_desc->spas);
422 	dev_dbg(dev, "%s: spa index: %d type: %s\n", __func__,
423 			spa->range_index,
424 			spa_type_name(nfit_spa_type(spa)));
425 	return true;
426 }
427 
428 static bool add_memdev(struct acpi_nfit_desc *acpi_desc,
429 		struct nfit_table_prev *prev,
430 		struct acpi_nfit_memory_map *memdev)
431 {
432 	struct device *dev = acpi_desc->dev;
433 	struct nfit_memdev *nfit_memdev;
434 
435 	if (memdev->header.length != sizeof(*memdev))
436 		return false;
437 
438 	list_for_each_entry(nfit_memdev, &prev->memdevs, list)
439 		if (memcmp(nfit_memdev->memdev, memdev, sizeof(*memdev)) == 0) {
440 			list_move_tail(&nfit_memdev->list, &acpi_desc->memdevs);
441 			return true;
442 		}
443 
444 	nfit_memdev = devm_kzalloc(dev, sizeof(*nfit_memdev) + sizeof(*memdev),
445 			GFP_KERNEL);
446 	if (!nfit_memdev)
447 		return false;
448 	INIT_LIST_HEAD(&nfit_memdev->list);
449 	memcpy(nfit_memdev->memdev, memdev, sizeof(*memdev));
450 	list_add_tail(&nfit_memdev->list, &acpi_desc->memdevs);
451 	dev_dbg(dev, "%s: memdev handle: %#x spa: %d dcr: %d\n",
452 			__func__, memdev->device_handle, memdev->range_index,
453 			memdev->region_index);
454 	return true;
455 }
456 
457 /*
458  * An implementation may provide a truncated control region if no block windows
459  * are defined.
460  */
461 static size_t sizeof_dcr(struct acpi_nfit_control_region *dcr)
462 {
463 	if (dcr->header.length < offsetof(struct acpi_nfit_control_region,
464 				window_size))
465 		return 0;
466 	if (dcr->windows)
467 		return sizeof(*dcr);
468 	return offsetof(struct acpi_nfit_control_region, window_size);
469 }
470 
471 static bool add_dcr(struct acpi_nfit_desc *acpi_desc,
472 		struct nfit_table_prev *prev,
473 		struct acpi_nfit_control_region *dcr)
474 {
475 	struct device *dev = acpi_desc->dev;
476 	struct nfit_dcr *nfit_dcr;
477 
478 	if (!sizeof_dcr(dcr))
479 		return false;
480 
481 	list_for_each_entry(nfit_dcr, &prev->dcrs, list)
482 		if (memcmp(nfit_dcr->dcr, dcr, sizeof_dcr(dcr)) == 0) {
483 			list_move_tail(&nfit_dcr->list, &acpi_desc->dcrs);
484 			return true;
485 		}
486 
487 	nfit_dcr = devm_kzalloc(dev, sizeof(*nfit_dcr) + sizeof(*dcr),
488 			GFP_KERNEL);
489 	if (!nfit_dcr)
490 		return false;
491 	INIT_LIST_HEAD(&nfit_dcr->list);
492 	memcpy(nfit_dcr->dcr, dcr, sizeof_dcr(dcr));
493 	list_add_tail(&nfit_dcr->list, &acpi_desc->dcrs);
494 	dev_dbg(dev, "%s: dcr index: %d windows: %d\n", __func__,
495 			dcr->region_index, dcr->windows);
496 	return true;
497 }
498 
499 static bool add_bdw(struct acpi_nfit_desc *acpi_desc,
500 		struct nfit_table_prev *prev,
501 		struct acpi_nfit_data_region *bdw)
502 {
503 	struct device *dev = acpi_desc->dev;
504 	struct nfit_bdw *nfit_bdw;
505 
506 	if (bdw->header.length != sizeof(*bdw))
507 		return false;
508 	list_for_each_entry(nfit_bdw, &prev->bdws, list)
509 		if (memcmp(nfit_bdw->bdw, bdw, sizeof(*bdw)) == 0) {
510 			list_move_tail(&nfit_bdw->list, &acpi_desc->bdws);
511 			return true;
512 		}
513 
514 	nfit_bdw = devm_kzalloc(dev, sizeof(*nfit_bdw) + sizeof(*bdw),
515 			GFP_KERNEL);
516 	if (!nfit_bdw)
517 		return false;
518 	INIT_LIST_HEAD(&nfit_bdw->list);
519 	memcpy(nfit_bdw->bdw, bdw, sizeof(*bdw));
520 	list_add_tail(&nfit_bdw->list, &acpi_desc->bdws);
521 	dev_dbg(dev, "%s: bdw dcr: %d windows: %d\n", __func__,
522 			bdw->region_index, bdw->windows);
523 	return true;
524 }
525 
526 static size_t sizeof_idt(struct acpi_nfit_interleave *idt)
527 {
528 	if (idt->header.length < sizeof(*idt))
529 		return 0;
530 	return sizeof(*idt) + sizeof(u32) * (idt->line_count - 1);
531 }
532 
533 static bool add_idt(struct acpi_nfit_desc *acpi_desc,
534 		struct nfit_table_prev *prev,
535 		struct acpi_nfit_interleave *idt)
536 {
537 	struct device *dev = acpi_desc->dev;
538 	struct nfit_idt *nfit_idt;
539 
540 	if (!sizeof_idt(idt))
541 		return false;
542 
543 	list_for_each_entry(nfit_idt, &prev->idts, list) {
544 		if (sizeof_idt(nfit_idt->idt) != sizeof_idt(idt))
545 			continue;
546 
547 		if (memcmp(nfit_idt->idt, idt, sizeof_idt(idt)) == 0) {
548 			list_move_tail(&nfit_idt->list, &acpi_desc->idts);
549 			return true;
550 		}
551 	}
552 
553 	nfit_idt = devm_kzalloc(dev, sizeof(*nfit_idt) + sizeof_idt(idt),
554 			GFP_KERNEL);
555 	if (!nfit_idt)
556 		return false;
557 	INIT_LIST_HEAD(&nfit_idt->list);
558 	memcpy(nfit_idt->idt, idt, sizeof_idt(idt));
559 	list_add_tail(&nfit_idt->list, &acpi_desc->idts);
560 	dev_dbg(dev, "%s: idt index: %d num_lines: %d\n", __func__,
561 			idt->interleave_index, idt->line_count);
562 	return true;
563 }
564 
565 static size_t sizeof_flush(struct acpi_nfit_flush_address *flush)
566 {
567 	if (flush->header.length < sizeof(*flush))
568 		return 0;
569 	return sizeof(*flush) + sizeof(u64) * (flush->hint_count - 1);
570 }
571 
572 static bool add_flush(struct acpi_nfit_desc *acpi_desc,
573 		struct nfit_table_prev *prev,
574 		struct acpi_nfit_flush_address *flush)
575 {
576 	struct device *dev = acpi_desc->dev;
577 	struct nfit_flush *nfit_flush;
578 
579 	if (!sizeof_flush(flush))
580 		return false;
581 
582 	list_for_each_entry(nfit_flush, &prev->flushes, list) {
583 		if (sizeof_flush(nfit_flush->flush) != sizeof_flush(flush))
584 			continue;
585 
586 		if (memcmp(nfit_flush->flush, flush,
587 					sizeof_flush(flush)) == 0) {
588 			list_move_tail(&nfit_flush->list, &acpi_desc->flushes);
589 			return true;
590 		}
591 	}
592 
593 	nfit_flush = devm_kzalloc(dev, sizeof(*nfit_flush)
594 			+ sizeof_flush(flush), GFP_KERNEL);
595 	if (!nfit_flush)
596 		return false;
597 	INIT_LIST_HEAD(&nfit_flush->list);
598 	memcpy(nfit_flush->flush, flush, sizeof_flush(flush));
599 	list_add_tail(&nfit_flush->list, &acpi_desc->flushes);
600 	dev_dbg(dev, "%s: nfit_flush handle: %d hint_count: %d\n", __func__,
601 			flush->device_handle, flush->hint_count);
602 	return true;
603 }
604 
605 static void *add_table(struct acpi_nfit_desc *acpi_desc,
606 		struct nfit_table_prev *prev, void *table, const void *end)
607 {
608 	struct device *dev = acpi_desc->dev;
609 	struct acpi_nfit_header *hdr;
610 	void *err = ERR_PTR(-ENOMEM);
611 
612 	if (table >= end)
613 		return NULL;
614 
615 	hdr = table;
616 	if (!hdr->length) {
617 		dev_warn(dev, "found a zero length table '%d' parsing nfit\n",
618 			hdr->type);
619 		return NULL;
620 	}
621 
622 	switch (hdr->type) {
623 	case ACPI_NFIT_TYPE_SYSTEM_ADDRESS:
624 		if (!add_spa(acpi_desc, prev, table))
625 			return err;
626 		break;
627 	case ACPI_NFIT_TYPE_MEMORY_MAP:
628 		if (!add_memdev(acpi_desc, prev, table))
629 			return err;
630 		break;
631 	case ACPI_NFIT_TYPE_CONTROL_REGION:
632 		if (!add_dcr(acpi_desc, prev, table))
633 			return err;
634 		break;
635 	case ACPI_NFIT_TYPE_DATA_REGION:
636 		if (!add_bdw(acpi_desc, prev, table))
637 			return err;
638 		break;
639 	case ACPI_NFIT_TYPE_INTERLEAVE:
640 		if (!add_idt(acpi_desc, prev, table))
641 			return err;
642 		break;
643 	case ACPI_NFIT_TYPE_FLUSH_ADDRESS:
644 		if (!add_flush(acpi_desc, prev, table))
645 			return err;
646 		break;
647 	case ACPI_NFIT_TYPE_SMBIOS:
648 		dev_dbg(dev, "%s: smbios\n", __func__);
649 		break;
650 	default:
651 		dev_err(dev, "unknown table '%d' parsing nfit\n", hdr->type);
652 		break;
653 	}
654 
655 	return table + hdr->length;
656 }
657 
658 static void nfit_mem_find_spa_bdw(struct acpi_nfit_desc *acpi_desc,
659 		struct nfit_mem *nfit_mem)
660 {
661 	u32 device_handle = __to_nfit_memdev(nfit_mem)->device_handle;
662 	u16 dcr = nfit_mem->dcr->region_index;
663 	struct nfit_spa *nfit_spa;
664 
665 	list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
666 		u16 range_index = nfit_spa->spa->range_index;
667 		int type = nfit_spa_type(nfit_spa->spa);
668 		struct nfit_memdev *nfit_memdev;
669 
670 		if (type != NFIT_SPA_BDW)
671 			continue;
672 
673 		list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) {
674 			if (nfit_memdev->memdev->range_index != range_index)
675 				continue;
676 			if (nfit_memdev->memdev->device_handle != device_handle)
677 				continue;
678 			if (nfit_memdev->memdev->region_index != dcr)
679 				continue;
680 
681 			nfit_mem->spa_bdw = nfit_spa->spa;
682 			return;
683 		}
684 	}
685 
686 	dev_dbg(acpi_desc->dev, "SPA-BDW not found for SPA-DCR %d\n",
687 			nfit_mem->spa_dcr->range_index);
688 	nfit_mem->bdw = NULL;
689 }
690 
691 static void nfit_mem_init_bdw(struct acpi_nfit_desc *acpi_desc,
692 		struct nfit_mem *nfit_mem, struct acpi_nfit_system_address *spa)
693 {
694 	u16 dcr = __to_nfit_memdev(nfit_mem)->region_index;
695 	struct nfit_memdev *nfit_memdev;
696 	struct nfit_bdw *nfit_bdw;
697 	struct nfit_idt *nfit_idt;
698 	u16 idt_idx, range_index;
699 
700 	list_for_each_entry(nfit_bdw, &acpi_desc->bdws, list) {
701 		if (nfit_bdw->bdw->region_index != dcr)
702 			continue;
703 		nfit_mem->bdw = nfit_bdw->bdw;
704 		break;
705 	}
706 
707 	if (!nfit_mem->bdw)
708 		return;
709 
710 	nfit_mem_find_spa_bdw(acpi_desc, nfit_mem);
711 
712 	if (!nfit_mem->spa_bdw)
713 		return;
714 
715 	range_index = nfit_mem->spa_bdw->range_index;
716 	list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) {
717 		if (nfit_memdev->memdev->range_index != range_index ||
718 				nfit_memdev->memdev->region_index != dcr)
719 			continue;
720 		nfit_mem->memdev_bdw = nfit_memdev->memdev;
721 		idt_idx = nfit_memdev->memdev->interleave_index;
722 		list_for_each_entry(nfit_idt, &acpi_desc->idts, list) {
723 			if (nfit_idt->idt->interleave_index != idt_idx)
724 				continue;
725 			nfit_mem->idt_bdw = nfit_idt->idt;
726 			break;
727 		}
728 		break;
729 	}
730 }
731 
732 static int nfit_mem_dcr_init(struct acpi_nfit_desc *acpi_desc,
733 		struct acpi_nfit_system_address *spa)
734 {
735 	struct nfit_mem *nfit_mem, *found;
736 	struct nfit_memdev *nfit_memdev;
737 	int type = nfit_spa_type(spa);
738 
739 	switch (type) {
740 	case NFIT_SPA_DCR:
741 	case NFIT_SPA_PM:
742 		break;
743 	default:
744 		return 0;
745 	}
746 
747 	list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) {
748 		struct nfit_flush *nfit_flush;
749 		struct nfit_dcr *nfit_dcr;
750 		u32 device_handle;
751 		u16 dcr;
752 
753 		if (nfit_memdev->memdev->range_index != spa->range_index)
754 			continue;
755 		found = NULL;
756 		dcr = nfit_memdev->memdev->region_index;
757 		device_handle = nfit_memdev->memdev->device_handle;
758 		list_for_each_entry(nfit_mem, &acpi_desc->dimms, list)
759 			if (__to_nfit_memdev(nfit_mem)->device_handle
760 					== device_handle) {
761 				found = nfit_mem;
762 				break;
763 			}
764 
765 		if (found)
766 			nfit_mem = found;
767 		else {
768 			nfit_mem = devm_kzalloc(acpi_desc->dev,
769 					sizeof(*nfit_mem), GFP_KERNEL);
770 			if (!nfit_mem)
771 				return -ENOMEM;
772 			INIT_LIST_HEAD(&nfit_mem->list);
773 			nfit_mem->acpi_desc = acpi_desc;
774 			list_add(&nfit_mem->list, &acpi_desc->dimms);
775 		}
776 
777 		list_for_each_entry(nfit_dcr, &acpi_desc->dcrs, list) {
778 			if (nfit_dcr->dcr->region_index != dcr)
779 				continue;
780 			/*
781 			 * Record the control region for the dimm.  For
782 			 * the ACPI 6.1 case, where there are separate
783 			 * control regions for the pmem vs blk
784 			 * interfaces, be sure to record the extended
785 			 * blk details.
786 			 */
787 			if (!nfit_mem->dcr)
788 				nfit_mem->dcr = nfit_dcr->dcr;
789 			else if (nfit_mem->dcr->windows == 0
790 					&& nfit_dcr->dcr->windows)
791 				nfit_mem->dcr = nfit_dcr->dcr;
792 			break;
793 		}
794 
795 		list_for_each_entry(nfit_flush, &acpi_desc->flushes, list) {
796 			struct acpi_nfit_flush_address *flush;
797 			u16 i;
798 
799 			if (nfit_flush->flush->device_handle != device_handle)
800 				continue;
801 			nfit_mem->nfit_flush = nfit_flush;
802 			flush = nfit_flush->flush;
803 			nfit_mem->flush_wpq = devm_kzalloc(acpi_desc->dev,
804 					flush->hint_count
805 					* sizeof(struct resource), GFP_KERNEL);
806 			if (!nfit_mem->flush_wpq)
807 				return -ENOMEM;
808 			for (i = 0; i < flush->hint_count; i++) {
809 				struct resource *res = &nfit_mem->flush_wpq[i];
810 
811 				res->start = flush->hint_address[i];
812 				res->end = res->start + 8 - 1;
813 			}
814 			break;
815 		}
816 
817 		if (dcr && !nfit_mem->dcr) {
818 			dev_err(acpi_desc->dev, "SPA %d missing DCR %d\n",
819 					spa->range_index, dcr);
820 			return -ENODEV;
821 		}
822 
823 		if (type == NFIT_SPA_DCR) {
824 			struct nfit_idt *nfit_idt;
825 			u16 idt_idx;
826 
827 			/* multiple dimms may share a SPA when interleaved */
828 			nfit_mem->spa_dcr = spa;
829 			nfit_mem->memdev_dcr = nfit_memdev->memdev;
830 			idt_idx = nfit_memdev->memdev->interleave_index;
831 			list_for_each_entry(nfit_idt, &acpi_desc->idts, list) {
832 				if (nfit_idt->idt->interleave_index != idt_idx)
833 					continue;
834 				nfit_mem->idt_dcr = nfit_idt->idt;
835 				break;
836 			}
837 			nfit_mem_init_bdw(acpi_desc, nfit_mem, spa);
838 		} else {
839 			/*
840 			 * A single dimm may belong to multiple SPA-PM
841 			 * ranges, record at least one in addition to
842 			 * any SPA-DCR range.
843 			 */
844 			nfit_mem->memdev_pmem = nfit_memdev->memdev;
845 		}
846 	}
847 
848 	return 0;
849 }
850 
851 static int nfit_mem_cmp(void *priv, struct list_head *_a, struct list_head *_b)
852 {
853 	struct nfit_mem *a = container_of(_a, typeof(*a), list);
854 	struct nfit_mem *b = container_of(_b, typeof(*b), list);
855 	u32 handleA, handleB;
856 
857 	handleA = __to_nfit_memdev(a)->device_handle;
858 	handleB = __to_nfit_memdev(b)->device_handle;
859 	if (handleA < handleB)
860 		return -1;
861 	else if (handleA > handleB)
862 		return 1;
863 	return 0;
864 }
865 
866 static int nfit_mem_init(struct acpi_nfit_desc *acpi_desc)
867 {
868 	struct nfit_spa *nfit_spa;
869 
870 	/*
871 	 * For each SPA-DCR or SPA-PMEM address range find its
872 	 * corresponding MEMDEV(s).  From each MEMDEV find the
873 	 * corresponding DCR.  Then, if we're operating on a SPA-DCR,
874 	 * try to find a SPA-BDW and a corresponding BDW that references
875 	 * the DCR.  Throw it all into an nfit_mem object.  Note, that
876 	 * BDWs are optional.
877 	 */
878 	list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
879 		int rc;
880 
881 		rc = nfit_mem_dcr_init(acpi_desc, nfit_spa->spa);
882 		if (rc)
883 			return rc;
884 	}
885 
886 	list_sort(NULL, &acpi_desc->dimms, nfit_mem_cmp);
887 
888 	return 0;
889 }
890 
891 static ssize_t revision_show(struct device *dev,
892 		struct device_attribute *attr, char *buf)
893 {
894 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
895 	struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
896 	struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
897 
898 	return sprintf(buf, "%d\n", acpi_desc->acpi_header.revision);
899 }
900 static DEVICE_ATTR_RO(revision);
901 
902 static ssize_t hw_error_scrub_show(struct device *dev,
903 		struct device_attribute *attr, char *buf)
904 {
905 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
906 	struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
907 	struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
908 
909 	return sprintf(buf, "%d\n", acpi_desc->scrub_mode);
910 }
911 
912 /*
913  * The 'hw_error_scrub' attribute can have the following values written to it:
914  * '0': Switch to the default mode where an exception will only insert
915  *      the address of the memory error into the poison and badblocks lists.
916  * '1': Enable a full scrub to happen if an exception for a memory error is
917  *      received.
918  */
919 static ssize_t hw_error_scrub_store(struct device *dev,
920 		struct device_attribute *attr, const char *buf, size_t size)
921 {
922 	struct nvdimm_bus_descriptor *nd_desc;
923 	ssize_t rc;
924 	long val;
925 
926 	rc = kstrtol(buf, 0, &val);
927 	if (rc)
928 		return rc;
929 
930 	device_lock(dev);
931 	nd_desc = dev_get_drvdata(dev);
932 	if (nd_desc) {
933 		struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
934 
935 		switch (val) {
936 		case HW_ERROR_SCRUB_ON:
937 			acpi_desc->scrub_mode = HW_ERROR_SCRUB_ON;
938 			break;
939 		case HW_ERROR_SCRUB_OFF:
940 			acpi_desc->scrub_mode = HW_ERROR_SCRUB_OFF;
941 			break;
942 		default:
943 			rc = -EINVAL;
944 			break;
945 		}
946 	}
947 	device_unlock(dev);
948 	if (rc)
949 		return rc;
950 	return size;
951 }
952 static DEVICE_ATTR_RW(hw_error_scrub);
953 
954 /*
955  * This shows the number of full Address Range Scrubs that have been
956  * completed since driver load time. Userspace can wait on this using
957  * select/poll etc. A '+' at the end indicates an ARS is in progress
958  */
959 static ssize_t scrub_show(struct device *dev,
960 		struct device_attribute *attr, char *buf)
961 {
962 	struct nvdimm_bus_descriptor *nd_desc;
963 	ssize_t rc = -ENXIO;
964 
965 	device_lock(dev);
966 	nd_desc = dev_get_drvdata(dev);
967 	if (nd_desc) {
968 		struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
969 
970 		rc = sprintf(buf, "%d%s", acpi_desc->scrub_count,
971 				(work_busy(&acpi_desc->work)) ? "+\n" : "\n");
972 	}
973 	device_unlock(dev);
974 	return rc;
975 }
976 
977 static ssize_t scrub_store(struct device *dev,
978 		struct device_attribute *attr, const char *buf, size_t size)
979 {
980 	struct nvdimm_bus_descriptor *nd_desc;
981 	ssize_t rc;
982 	long val;
983 
984 	rc = kstrtol(buf, 0, &val);
985 	if (rc)
986 		return rc;
987 	if (val != 1)
988 		return -EINVAL;
989 
990 	device_lock(dev);
991 	nd_desc = dev_get_drvdata(dev);
992 	if (nd_desc) {
993 		struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
994 
995 		rc = acpi_nfit_ars_rescan(acpi_desc);
996 	}
997 	device_unlock(dev);
998 	if (rc)
999 		return rc;
1000 	return size;
1001 }
1002 static DEVICE_ATTR_RW(scrub);
1003 
1004 static bool ars_supported(struct nvdimm_bus *nvdimm_bus)
1005 {
1006 	struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
1007 	const unsigned long mask = 1 << ND_CMD_ARS_CAP | 1 << ND_CMD_ARS_START
1008 		| 1 << ND_CMD_ARS_STATUS;
1009 
1010 	return (nd_desc->cmd_mask & mask) == mask;
1011 }
1012 
1013 static umode_t nfit_visible(struct kobject *kobj, struct attribute *a, int n)
1014 {
1015 	struct device *dev = container_of(kobj, struct device, kobj);
1016 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
1017 
1018 	if (a == &dev_attr_scrub.attr && !ars_supported(nvdimm_bus))
1019 		return 0;
1020 	return a->mode;
1021 }
1022 
1023 static struct attribute *acpi_nfit_attributes[] = {
1024 	&dev_attr_revision.attr,
1025 	&dev_attr_scrub.attr,
1026 	&dev_attr_hw_error_scrub.attr,
1027 	NULL,
1028 };
1029 
1030 static struct attribute_group acpi_nfit_attribute_group = {
1031 	.name = "nfit",
1032 	.attrs = acpi_nfit_attributes,
1033 	.is_visible = nfit_visible,
1034 };
1035 
1036 static const struct attribute_group *acpi_nfit_attribute_groups[] = {
1037 	&nvdimm_bus_attribute_group,
1038 	&acpi_nfit_attribute_group,
1039 	NULL,
1040 };
1041 
1042 static struct acpi_nfit_memory_map *to_nfit_memdev(struct device *dev)
1043 {
1044 	struct nvdimm *nvdimm = to_nvdimm(dev);
1045 	struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
1046 
1047 	return __to_nfit_memdev(nfit_mem);
1048 }
1049 
1050 static struct acpi_nfit_control_region *to_nfit_dcr(struct device *dev)
1051 {
1052 	struct nvdimm *nvdimm = to_nvdimm(dev);
1053 	struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
1054 
1055 	return nfit_mem->dcr;
1056 }
1057 
1058 static ssize_t handle_show(struct device *dev,
1059 		struct device_attribute *attr, char *buf)
1060 {
1061 	struct acpi_nfit_memory_map *memdev = to_nfit_memdev(dev);
1062 
1063 	return sprintf(buf, "%#x\n", memdev->device_handle);
1064 }
1065 static DEVICE_ATTR_RO(handle);
1066 
1067 static ssize_t phys_id_show(struct device *dev,
1068 		struct device_attribute *attr, char *buf)
1069 {
1070 	struct acpi_nfit_memory_map *memdev = to_nfit_memdev(dev);
1071 
1072 	return sprintf(buf, "%#x\n", memdev->physical_id);
1073 }
1074 static DEVICE_ATTR_RO(phys_id);
1075 
1076 static ssize_t vendor_show(struct device *dev,
1077 		struct device_attribute *attr, char *buf)
1078 {
1079 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1080 
1081 	return sprintf(buf, "0x%04x\n", be16_to_cpu(dcr->vendor_id));
1082 }
1083 static DEVICE_ATTR_RO(vendor);
1084 
1085 static ssize_t rev_id_show(struct device *dev,
1086 		struct device_attribute *attr, char *buf)
1087 {
1088 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1089 
1090 	return sprintf(buf, "0x%04x\n", be16_to_cpu(dcr->revision_id));
1091 }
1092 static DEVICE_ATTR_RO(rev_id);
1093 
1094 static ssize_t device_show(struct device *dev,
1095 		struct device_attribute *attr, char *buf)
1096 {
1097 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1098 
1099 	return sprintf(buf, "0x%04x\n", be16_to_cpu(dcr->device_id));
1100 }
1101 static DEVICE_ATTR_RO(device);
1102 
1103 static ssize_t subsystem_vendor_show(struct device *dev,
1104 		struct device_attribute *attr, char *buf)
1105 {
1106 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1107 
1108 	return sprintf(buf, "0x%04x\n", be16_to_cpu(dcr->subsystem_vendor_id));
1109 }
1110 static DEVICE_ATTR_RO(subsystem_vendor);
1111 
1112 static ssize_t subsystem_rev_id_show(struct device *dev,
1113 		struct device_attribute *attr, char *buf)
1114 {
1115 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1116 
1117 	return sprintf(buf, "0x%04x\n",
1118 			be16_to_cpu(dcr->subsystem_revision_id));
1119 }
1120 static DEVICE_ATTR_RO(subsystem_rev_id);
1121 
1122 static ssize_t subsystem_device_show(struct device *dev,
1123 		struct device_attribute *attr, char *buf)
1124 {
1125 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1126 
1127 	return sprintf(buf, "0x%04x\n", be16_to_cpu(dcr->subsystem_device_id));
1128 }
1129 static DEVICE_ATTR_RO(subsystem_device);
1130 
1131 static int num_nvdimm_formats(struct nvdimm *nvdimm)
1132 {
1133 	struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
1134 	int formats = 0;
1135 
1136 	if (nfit_mem->memdev_pmem)
1137 		formats++;
1138 	if (nfit_mem->memdev_bdw)
1139 		formats++;
1140 	return formats;
1141 }
1142 
1143 static ssize_t format_show(struct device *dev,
1144 		struct device_attribute *attr, char *buf)
1145 {
1146 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1147 
1148 	return sprintf(buf, "0x%04x\n", le16_to_cpu(dcr->code));
1149 }
1150 static DEVICE_ATTR_RO(format);
1151 
1152 static ssize_t format1_show(struct device *dev,
1153 		struct device_attribute *attr, char *buf)
1154 {
1155 	u32 handle;
1156 	ssize_t rc = -ENXIO;
1157 	struct nfit_mem *nfit_mem;
1158 	struct nfit_memdev *nfit_memdev;
1159 	struct acpi_nfit_desc *acpi_desc;
1160 	struct nvdimm *nvdimm = to_nvdimm(dev);
1161 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1162 
1163 	nfit_mem = nvdimm_provider_data(nvdimm);
1164 	acpi_desc = nfit_mem->acpi_desc;
1165 	handle = to_nfit_memdev(dev)->device_handle;
1166 
1167 	/* assumes DIMMs have at most 2 published interface codes */
1168 	mutex_lock(&acpi_desc->init_mutex);
1169 	list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) {
1170 		struct acpi_nfit_memory_map *memdev = nfit_memdev->memdev;
1171 		struct nfit_dcr *nfit_dcr;
1172 
1173 		if (memdev->device_handle != handle)
1174 			continue;
1175 
1176 		list_for_each_entry(nfit_dcr, &acpi_desc->dcrs, list) {
1177 			if (nfit_dcr->dcr->region_index != memdev->region_index)
1178 				continue;
1179 			if (nfit_dcr->dcr->code == dcr->code)
1180 				continue;
1181 			rc = sprintf(buf, "0x%04x\n",
1182 					le16_to_cpu(nfit_dcr->dcr->code));
1183 			break;
1184 		}
1185 		if (rc != ENXIO)
1186 			break;
1187 	}
1188 	mutex_unlock(&acpi_desc->init_mutex);
1189 	return rc;
1190 }
1191 static DEVICE_ATTR_RO(format1);
1192 
1193 static ssize_t formats_show(struct device *dev,
1194 		struct device_attribute *attr, char *buf)
1195 {
1196 	struct nvdimm *nvdimm = to_nvdimm(dev);
1197 
1198 	return sprintf(buf, "%d\n", num_nvdimm_formats(nvdimm));
1199 }
1200 static DEVICE_ATTR_RO(formats);
1201 
1202 static ssize_t serial_show(struct device *dev,
1203 		struct device_attribute *attr, char *buf)
1204 {
1205 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1206 
1207 	return sprintf(buf, "0x%08x\n", be32_to_cpu(dcr->serial_number));
1208 }
1209 static DEVICE_ATTR_RO(serial);
1210 
1211 static ssize_t family_show(struct device *dev,
1212 		struct device_attribute *attr, char *buf)
1213 {
1214 	struct nvdimm *nvdimm = to_nvdimm(dev);
1215 	struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
1216 
1217 	if (nfit_mem->family < 0)
1218 		return -ENXIO;
1219 	return sprintf(buf, "%d\n", nfit_mem->family);
1220 }
1221 static DEVICE_ATTR_RO(family);
1222 
1223 static ssize_t dsm_mask_show(struct device *dev,
1224 		struct device_attribute *attr, char *buf)
1225 {
1226 	struct nvdimm *nvdimm = to_nvdimm(dev);
1227 	struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
1228 
1229 	if (nfit_mem->family < 0)
1230 		return -ENXIO;
1231 	return sprintf(buf, "%#lx\n", nfit_mem->dsm_mask);
1232 }
1233 static DEVICE_ATTR_RO(dsm_mask);
1234 
1235 static ssize_t flags_show(struct device *dev,
1236 		struct device_attribute *attr, char *buf)
1237 {
1238 	u16 flags = to_nfit_memdev(dev)->flags;
1239 
1240 	return sprintf(buf, "%s%s%s%s%s\n",
1241 		flags & ACPI_NFIT_MEM_SAVE_FAILED ? "save_fail " : "",
1242 		flags & ACPI_NFIT_MEM_RESTORE_FAILED ? "restore_fail " : "",
1243 		flags & ACPI_NFIT_MEM_FLUSH_FAILED ? "flush_fail " : "",
1244 		flags & ACPI_NFIT_MEM_NOT_ARMED ? "not_armed " : "",
1245 		flags & ACPI_NFIT_MEM_HEALTH_OBSERVED ? "smart_event " : "");
1246 }
1247 static DEVICE_ATTR_RO(flags);
1248 
1249 static ssize_t id_show(struct device *dev,
1250 		struct device_attribute *attr, char *buf)
1251 {
1252 	struct acpi_nfit_control_region *dcr = to_nfit_dcr(dev);
1253 
1254 	if (dcr->valid_fields & ACPI_NFIT_CONTROL_MFG_INFO_VALID)
1255 		return sprintf(buf, "%04x-%02x-%04x-%08x\n",
1256 				be16_to_cpu(dcr->vendor_id),
1257 				dcr->manufacturing_location,
1258 				be16_to_cpu(dcr->manufacturing_date),
1259 				be32_to_cpu(dcr->serial_number));
1260 	else
1261 		return sprintf(buf, "%04x-%08x\n",
1262 				be16_to_cpu(dcr->vendor_id),
1263 				be32_to_cpu(dcr->serial_number));
1264 }
1265 static DEVICE_ATTR_RO(id);
1266 
1267 static struct attribute *acpi_nfit_dimm_attributes[] = {
1268 	&dev_attr_handle.attr,
1269 	&dev_attr_phys_id.attr,
1270 	&dev_attr_vendor.attr,
1271 	&dev_attr_device.attr,
1272 	&dev_attr_rev_id.attr,
1273 	&dev_attr_subsystem_vendor.attr,
1274 	&dev_attr_subsystem_device.attr,
1275 	&dev_attr_subsystem_rev_id.attr,
1276 	&dev_attr_format.attr,
1277 	&dev_attr_formats.attr,
1278 	&dev_attr_format1.attr,
1279 	&dev_attr_serial.attr,
1280 	&dev_attr_flags.attr,
1281 	&dev_attr_id.attr,
1282 	&dev_attr_family.attr,
1283 	&dev_attr_dsm_mask.attr,
1284 	NULL,
1285 };
1286 
1287 static umode_t acpi_nfit_dimm_attr_visible(struct kobject *kobj,
1288 		struct attribute *a, int n)
1289 {
1290 	struct device *dev = container_of(kobj, struct device, kobj);
1291 	struct nvdimm *nvdimm = to_nvdimm(dev);
1292 
1293 	if (!to_nfit_dcr(dev))
1294 		return 0;
1295 	if (a == &dev_attr_format1.attr && num_nvdimm_formats(nvdimm) <= 1)
1296 		return 0;
1297 	return a->mode;
1298 }
1299 
1300 static struct attribute_group acpi_nfit_dimm_attribute_group = {
1301 	.name = "nfit",
1302 	.attrs = acpi_nfit_dimm_attributes,
1303 	.is_visible = acpi_nfit_dimm_attr_visible,
1304 };
1305 
1306 static const struct attribute_group *acpi_nfit_dimm_attribute_groups[] = {
1307 	&nvdimm_attribute_group,
1308 	&nd_device_attribute_group,
1309 	&acpi_nfit_dimm_attribute_group,
1310 	NULL,
1311 };
1312 
1313 static struct nvdimm *acpi_nfit_dimm_by_handle(struct acpi_nfit_desc *acpi_desc,
1314 		u32 device_handle)
1315 {
1316 	struct nfit_mem *nfit_mem;
1317 
1318 	list_for_each_entry(nfit_mem, &acpi_desc->dimms, list)
1319 		if (__to_nfit_memdev(nfit_mem)->device_handle == device_handle)
1320 			return nfit_mem->nvdimm;
1321 
1322 	return NULL;
1323 }
1324 
1325 void __acpi_nvdimm_notify(struct device *dev, u32 event)
1326 {
1327 	struct nfit_mem *nfit_mem;
1328 	struct acpi_nfit_desc *acpi_desc;
1329 
1330 	dev_dbg(dev->parent, "%s: %s: event: %d\n", dev_name(dev), __func__,
1331 			event);
1332 
1333 	if (event != NFIT_NOTIFY_DIMM_HEALTH) {
1334 		dev_dbg(dev->parent, "%s: unknown event: %d\n", dev_name(dev),
1335 				event);
1336 		return;
1337 	}
1338 
1339 	acpi_desc = dev_get_drvdata(dev->parent);
1340 	if (!acpi_desc)
1341 		return;
1342 
1343 	/*
1344 	 * If we successfully retrieved acpi_desc, then we know nfit_mem data
1345 	 * is still valid.
1346 	 */
1347 	nfit_mem = dev_get_drvdata(dev);
1348 	if (nfit_mem && nfit_mem->flags_attr)
1349 		sysfs_notify_dirent(nfit_mem->flags_attr);
1350 }
1351 EXPORT_SYMBOL_GPL(__acpi_nvdimm_notify);
1352 
1353 static void acpi_nvdimm_notify(acpi_handle handle, u32 event, void *data)
1354 {
1355 	struct acpi_device *adev = data;
1356 	struct device *dev = &adev->dev;
1357 
1358 	device_lock(dev->parent);
1359 	__acpi_nvdimm_notify(dev, event);
1360 	device_unlock(dev->parent);
1361 }
1362 
1363 static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
1364 		struct nfit_mem *nfit_mem, u32 device_handle)
1365 {
1366 	struct acpi_device *adev, *adev_dimm;
1367 	struct device *dev = acpi_desc->dev;
1368 	unsigned long dsm_mask;
1369 	const u8 *uuid;
1370 	int i;
1371 
1372 	/* nfit test assumes 1:1 relationship between commands and dsms */
1373 	nfit_mem->dsm_mask = acpi_desc->dimm_cmd_force_en;
1374 	nfit_mem->family = NVDIMM_FAMILY_INTEL;
1375 	adev = to_acpi_dev(acpi_desc);
1376 	if (!adev)
1377 		return 0;
1378 
1379 	adev_dimm = acpi_find_child_device(adev, device_handle, false);
1380 	nfit_mem->adev = adev_dimm;
1381 	if (!adev_dimm) {
1382 		dev_err(dev, "no ACPI.NFIT device with _ADR %#x, disabling...\n",
1383 				device_handle);
1384 		return force_enable_dimms ? 0 : -ENODEV;
1385 	}
1386 
1387 	if (ACPI_FAILURE(acpi_install_notify_handler(adev_dimm->handle,
1388 		ACPI_DEVICE_NOTIFY, acpi_nvdimm_notify, adev_dimm))) {
1389 		dev_err(dev, "%s: notification registration failed\n",
1390 				dev_name(&adev_dimm->dev));
1391 		return -ENXIO;
1392 	}
1393 
1394 	/*
1395 	 * Until standardization materializes we need to consider 4
1396 	 * different command sets.  Note, that checking for function0 (bit0)
1397 	 * tells us if any commands are reachable through this uuid.
1398 	 */
1399 	for (i = NVDIMM_FAMILY_INTEL; i <= NVDIMM_FAMILY_MSFT; i++)
1400 		if (acpi_check_dsm(adev_dimm->handle, to_nfit_uuid(i), 1, 1))
1401 			break;
1402 
1403 	/* limit the supported commands to those that are publicly documented */
1404 	nfit_mem->family = i;
1405 	if (nfit_mem->family == NVDIMM_FAMILY_INTEL) {
1406 		dsm_mask = 0x3fe;
1407 		if (disable_vendor_specific)
1408 			dsm_mask &= ~(1 << ND_CMD_VENDOR);
1409 	} else if (nfit_mem->family == NVDIMM_FAMILY_HPE1) {
1410 		dsm_mask = 0x1c3c76;
1411 	} else if (nfit_mem->family == NVDIMM_FAMILY_HPE2) {
1412 		dsm_mask = 0x1fe;
1413 		if (disable_vendor_specific)
1414 			dsm_mask &= ~(1 << 8);
1415 	} else if (nfit_mem->family == NVDIMM_FAMILY_MSFT) {
1416 		dsm_mask = 0xffffffff;
1417 	} else {
1418 		dev_dbg(dev, "unknown dimm command family\n");
1419 		nfit_mem->family = -1;
1420 		/* DSMs are optional, continue loading the driver... */
1421 		return 0;
1422 	}
1423 
1424 	uuid = to_nfit_uuid(nfit_mem->family);
1425 	for_each_set_bit(i, &dsm_mask, BITS_PER_LONG)
1426 		if (acpi_check_dsm(adev_dimm->handle, uuid, 1, 1ULL << i))
1427 			set_bit(i, &nfit_mem->dsm_mask);
1428 
1429 	return 0;
1430 }
1431 
1432 static void shutdown_dimm_notify(void *data)
1433 {
1434 	struct acpi_nfit_desc *acpi_desc = data;
1435 	struct nfit_mem *nfit_mem;
1436 
1437 	mutex_lock(&acpi_desc->init_mutex);
1438 	/*
1439 	 * Clear out the nfit_mem->flags_attr and shut down dimm event
1440 	 * notifications.
1441 	 */
1442 	list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) {
1443 		struct acpi_device *adev_dimm = nfit_mem->adev;
1444 
1445 		if (nfit_mem->flags_attr) {
1446 			sysfs_put(nfit_mem->flags_attr);
1447 			nfit_mem->flags_attr = NULL;
1448 		}
1449 		if (adev_dimm)
1450 			acpi_remove_notify_handler(adev_dimm->handle,
1451 					ACPI_DEVICE_NOTIFY, acpi_nvdimm_notify);
1452 	}
1453 	mutex_unlock(&acpi_desc->init_mutex);
1454 }
1455 
1456 static int acpi_nfit_register_dimms(struct acpi_nfit_desc *acpi_desc)
1457 {
1458 	struct nfit_mem *nfit_mem;
1459 	int dimm_count = 0, rc;
1460 	struct nvdimm *nvdimm;
1461 
1462 	list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) {
1463 		struct acpi_nfit_flush_address *flush;
1464 		unsigned long flags = 0, cmd_mask;
1465 		u32 device_handle;
1466 		u16 mem_flags;
1467 
1468 		device_handle = __to_nfit_memdev(nfit_mem)->device_handle;
1469 		nvdimm = acpi_nfit_dimm_by_handle(acpi_desc, device_handle);
1470 		if (nvdimm) {
1471 			dimm_count++;
1472 			continue;
1473 		}
1474 
1475 		if (nfit_mem->bdw && nfit_mem->memdev_pmem)
1476 			flags |= NDD_ALIASING;
1477 
1478 		mem_flags = __to_nfit_memdev(nfit_mem)->flags;
1479 		if (mem_flags & ACPI_NFIT_MEM_NOT_ARMED)
1480 			flags |= NDD_UNARMED;
1481 
1482 		rc = acpi_nfit_add_dimm(acpi_desc, nfit_mem, device_handle);
1483 		if (rc)
1484 			continue;
1485 
1486 		/*
1487 		 * TODO: provide translation for non-NVDIMM_FAMILY_INTEL
1488 		 * devices (i.e. from nd_cmd to acpi_dsm) to standardize the
1489 		 * userspace interface.
1490 		 */
1491 		cmd_mask = 1UL << ND_CMD_CALL;
1492 		if (nfit_mem->family == NVDIMM_FAMILY_INTEL)
1493 			cmd_mask |= nfit_mem->dsm_mask;
1494 
1495 		flush = nfit_mem->nfit_flush ? nfit_mem->nfit_flush->flush
1496 			: NULL;
1497 		nvdimm = nvdimm_create(acpi_desc->nvdimm_bus, nfit_mem,
1498 				acpi_nfit_dimm_attribute_groups,
1499 				flags, cmd_mask, flush ? flush->hint_count : 0,
1500 				nfit_mem->flush_wpq);
1501 		if (!nvdimm)
1502 			return -ENOMEM;
1503 
1504 		nfit_mem->nvdimm = nvdimm;
1505 		dimm_count++;
1506 
1507 		if ((mem_flags & ACPI_NFIT_MEM_FAILED_MASK) == 0)
1508 			continue;
1509 
1510 		dev_info(acpi_desc->dev, "%s flags:%s%s%s%s\n",
1511 				nvdimm_name(nvdimm),
1512 		  mem_flags & ACPI_NFIT_MEM_SAVE_FAILED ? " save_fail" : "",
1513 		  mem_flags & ACPI_NFIT_MEM_RESTORE_FAILED ? " restore_fail":"",
1514 		  mem_flags & ACPI_NFIT_MEM_FLUSH_FAILED ? " flush_fail" : "",
1515 		  mem_flags & ACPI_NFIT_MEM_NOT_ARMED ? " not_armed" : "");
1516 
1517 	}
1518 
1519 	rc = nvdimm_bus_check_dimm_count(acpi_desc->nvdimm_bus, dimm_count);
1520 	if (rc)
1521 		return rc;
1522 
1523 	/*
1524 	 * Now that dimms are successfully registered, and async registration
1525 	 * is flushed, attempt to enable event notification.
1526 	 */
1527 	list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) {
1528 		struct kernfs_node *nfit_kernfs;
1529 
1530 		nvdimm = nfit_mem->nvdimm;
1531 		nfit_kernfs = sysfs_get_dirent(nvdimm_kobj(nvdimm)->sd, "nfit");
1532 		if (nfit_kernfs)
1533 			nfit_mem->flags_attr = sysfs_get_dirent(nfit_kernfs,
1534 					"flags");
1535 		sysfs_put(nfit_kernfs);
1536 		if (!nfit_mem->flags_attr)
1537 			dev_warn(acpi_desc->dev, "%s: notifications disabled\n",
1538 					nvdimm_name(nvdimm));
1539 	}
1540 
1541 	return devm_add_action_or_reset(acpi_desc->dev, shutdown_dimm_notify,
1542 			acpi_desc);
1543 }
1544 
1545 static void acpi_nfit_init_dsms(struct acpi_nfit_desc *acpi_desc)
1546 {
1547 	struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
1548 	const u8 *uuid = to_nfit_uuid(NFIT_DEV_BUS);
1549 	struct acpi_device *adev;
1550 	int i;
1551 
1552 	nd_desc->cmd_mask = acpi_desc->bus_cmd_force_en;
1553 	adev = to_acpi_dev(acpi_desc);
1554 	if (!adev)
1555 		return;
1556 
1557 	for (i = ND_CMD_ARS_CAP; i <= ND_CMD_CLEAR_ERROR; i++)
1558 		if (acpi_check_dsm(adev->handle, uuid, 1, 1ULL << i))
1559 			set_bit(i, &nd_desc->cmd_mask);
1560 }
1561 
1562 static ssize_t range_index_show(struct device *dev,
1563 		struct device_attribute *attr, char *buf)
1564 {
1565 	struct nd_region *nd_region = to_nd_region(dev);
1566 	struct nfit_spa *nfit_spa = nd_region_provider_data(nd_region);
1567 
1568 	return sprintf(buf, "%d\n", nfit_spa->spa->range_index);
1569 }
1570 static DEVICE_ATTR_RO(range_index);
1571 
1572 static struct attribute *acpi_nfit_region_attributes[] = {
1573 	&dev_attr_range_index.attr,
1574 	NULL,
1575 };
1576 
1577 static struct attribute_group acpi_nfit_region_attribute_group = {
1578 	.name = "nfit",
1579 	.attrs = acpi_nfit_region_attributes,
1580 };
1581 
1582 static const struct attribute_group *acpi_nfit_region_attribute_groups[] = {
1583 	&nd_region_attribute_group,
1584 	&nd_mapping_attribute_group,
1585 	&nd_device_attribute_group,
1586 	&nd_numa_attribute_group,
1587 	&acpi_nfit_region_attribute_group,
1588 	NULL,
1589 };
1590 
1591 /* enough info to uniquely specify an interleave set */
1592 struct nfit_set_info {
1593 	struct nfit_set_info_map {
1594 		u64 region_offset;
1595 		u32 serial_number;
1596 		u32 pad;
1597 	} mapping[0];
1598 };
1599 
1600 static size_t sizeof_nfit_set_info(int num_mappings)
1601 {
1602 	return sizeof(struct nfit_set_info)
1603 		+ num_mappings * sizeof(struct nfit_set_info_map);
1604 }
1605 
1606 static int cmp_map_compat(const void *m0, const void *m1)
1607 {
1608 	const struct nfit_set_info_map *map0 = m0;
1609 	const struct nfit_set_info_map *map1 = m1;
1610 
1611 	return memcmp(&map0->region_offset, &map1->region_offset,
1612 			sizeof(u64));
1613 }
1614 
1615 static int cmp_map(const void *m0, const void *m1)
1616 {
1617 	const struct nfit_set_info_map *map0 = m0;
1618 	const struct nfit_set_info_map *map1 = m1;
1619 
1620 	if (map0->region_offset < map1->region_offset)
1621 		return -1;
1622 	else if (map0->region_offset > map1->region_offset)
1623 		return 1;
1624 	return 0;
1625 }
1626 
1627 /* Retrieve the nth entry referencing this spa */
1628 static struct acpi_nfit_memory_map *memdev_from_spa(
1629 		struct acpi_nfit_desc *acpi_desc, u16 range_index, int n)
1630 {
1631 	struct nfit_memdev *nfit_memdev;
1632 
1633 	list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list)
1634 		if (nfit_memdev->memdev->range_index == range_index)
1635 			if (n-- == 0)
1636 				return nfit_memdev->memdev;
1637 	return NULL;
1638 }
1639 
1640 static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
1641 		struct nd_region_desc *ndr_desc,
1642 		struct acpi_nfit_system_address *spa)
1643 {
1644 	int i, spa_type = nfit_spa_type(spa);
1645 	struct device *dev = acpi_desc->dev;
1646 	struct nd_interleave_set *nd_set;
1647 	u16 nr = ndr_desc->num_mappings;
1648 	struct nfit_set_info *info;
1649 
1650 	if (spa_type == NFIT_SPA_PM || spa_type == NFIT_SPA_VOLATILE)
1651 		/* pass */;
1652 	else
1653 		return 0;
1654 
1655 	nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL);
1656 	if (!nd_set)
1657 		return -ENOMEM;
1658 
1659 	info = devm_kzalloc(dev, sizeof_nfit_set_info(nr), GFP_KERNEL);
1660 	if (!info)
1661 		return -ENOMEM;
1662 	for (i = 0; i < nr; i++) {
1663 		struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
1664 		struct nfit_set_info_map *map = &info->mapping[i];
1665 		struct nvdimm *nvdimm = mapping->nvdimm;
1666 		struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
1667 		struct acpi_nfit_memory_map *memdev = memdev_from_spa(acpi_desc,
1668 				spa->range_index, i);
1669 
1670 		if (!memdev || !nfit_mem->dcr) {
1671 			dev_err(dev, "%s: failed to find DCR\n", __func__);
1672 			return -ENODEV;
1673 		}
1674 
1675 		map->region_offset = memdev->region_offset;
1676 		map->serial_number = nfit_mem->dcr->serial_number;
1677 	}
1678 
1679 	sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
1680 			cmp_map, NULL);
1681 	nd_set->cookie = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
1682 
1683 	/* support namespaces created with the wrong sort order */
1684 	sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
1685 			cmp_map_compat, NULL);
1686 	nd_set->altcookie = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
1687 
1688 	ndr_desc->nd_set = nd_set;
1689 	devm_kfree(dev, info);
1690 
1691 	return 0;
1692 }
1693 
1694 static u64 to_interleave_offset(u64 offset, struct nfit_blk_mmio *mmio)
1695 {
1696 	struct acpi_nfit_interleave *idt = mmio->idt;
1697 	u32 sub_line_offset, line_index, line_offset;
1698 	u64 line_no, table_skip_count, table_offset;
1699 
1700 	line_no = div_u64_rem(offset, mmio->line_size, &sub_line_offset);
1701 	table_skip_count = div_u64_rem(line_no, mmio->num_lines, &line_index);
1702 	line_offset = idt->line_offset[line_index]
1703 		* mmio->line_size;
1704 	table_offset = table_skip_count * mmio->table_size;
1705 
1706 	return mmio->base_offset + line_offset + table_offset + sub_line_offset;
1707 }
1708 
1709 static u32 read_blk_stat(struct nfit_blk *nfit_blk, unsigned int bw)
1710 {
1711 	struct nfit_blk_mmio *mmio = &nfit_blk->mmio[DCR];
1712 	u64 offset = nfit_blk->stat_offset + mmio->size * bw;
1713 	const u32 STATUS_MASK = 0x80000037;
1714 
1715 	if (mmio->num_lines)
1716 		offset = to_interleave_offset(offset, mmio);
1717 
1718 	return readl(mmio->addr.base + offset) & STATUS_MASK;
1719 }
1720 
1721 static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw,
1722 		resource_size_t dpa, unsigned int len, unsigned int write)
1723 {
1724 	u64 cmd, offset;
1725 	struct nfit_blk_mmio *mmio = &nfit_blk->mmio[DCR];
1726 
1727 	enum {
1728 		BCW_OFFSET_MASK = (1ULL << 48)-1,
1729 		BCW_LEN_SHIFT = 48,
1730 		BCW_LEN_MASK = (1ULL << 8) - 1,
1731 		BCW_CMD_SHIFT = 56,
1732 	};
1733 
1734 	cmd = (dpa >> L1_CACHE_SHIFT) & BCW_OFFSET_MASK;
1735 	len = len >> L1_CACHE_SHIFT;
1736 	cmd |= ((u64) len & BCW_LEN_MASK) << BCW_LEN_SHIFT;
1737 	cmd |= ((u64) write) << BCW_CMD_SHIFT;
1738 
1739 	offset = nfit_blk->cmd_offset + mmio->size * bw;
1740 	if (mmio->num_lines)
1741 		offset = to_interleave_offset(offset, mmio);
1742 
1743 	writeq(cmd, mmio->addr.base + offset);
1744 	nvdimm_flush(nfit_blk->nd_region);
1745 
1746 	if (nfit_blk->dimm_flags & NFIT_BLK_DCR_LATCH)
1747 		readq(mmio->addr.base + offset);
1748 }
1749 
1750 static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk,
1751 		resource_size_t dpa, void *iobuf, size_t len, int rw,
1752 		unsigned int lane)
1753 {
1754 	struct nfit_blk_mmio *mmio = &nfit_blk->mmio[BDW];
1755 	unsigned int copied = 0;
1756 	u64 base_offset;
1757 	int rc;
1758 
1759 	base_offset = nfit_blk->bdw_offset + dpa % L1_CACHE_BYTES
1760 		+ lane * mmio->size;
1761 	write_blk_ctl(nfit_blk, lane, dpa, len, rw);
1762 	while (len) {
1763 		unsigned int c;
1764 		u64 offset;
1765 
1766 		if (mmio->num_lines) {
1767 			u32 line_offset;
1768 
1769 			offset = to_interleave_offset(base_offset + copied,
1770 					mmio);
1771 			div_u64_rem(offset, mmio->line_size, &line_offset);
1772 			c = min_t(size_t, len, mmio->line_size - line_offset);
1773 		} else {
1774 			offset = base_offset + nfit_blk->bdw_offset;
1775 			c = len;
1776 		}
1777 
1778 		if (rw)
1779 			memcpy_to_pmem(mmio->addr.aperture + offset,
1780 					iobuf + copied, c);
1781 		else {
1782 			if (nfit_blk->dimm_flags & NFIT_BLK_READ_FLUSH)
1783 				mmio_flush_range((void __force *)
1784 					mmio->addr.aperture + offset, c);
1785 
1786 			memcpy_from_pmem(iobuf + copied,
1787 					mmio->addr.aperture + offset, c);
1788 		}
1789 
1790 		copied += c;
1791 		len -= c;
1792 	}
1793 
1794 	if (rw)
1795 		nvdimm_flush(nfit_blk->nd_region);
1796 
1797 	rc = read_blk_stat(nfit_blk, lane) ? -EIO : 0;
1798 	return rc;
1799 }
1800 
1801 static int acpi_nfit_blk_region_do_io(struct nd_blk_region *ndbr,
1802 		resource_size_t dpa, void *iobuf, u64 len, int rw)
1803 {
1804 	struct nfit_blk *nfit_blk = nd_blk_region_provider_data(ndbr);
1805 	struct nfit_blk_mmio *mmio = &nfit_blk->mmio[BDW];
1806 	struct nd_region *nd_region = nfit_blk->nd_region;
1807 	unsigned int lane, copied = 0;
1808 	int rc = 0;
1809 
1810 	lane = nd_region_acquire_lane(nd_region);
1811 	while (len) {
1812 		u64 c = min(len, mmio->size);
1813 
1814 		rc = acpi_nfit_blk_single_io(nfit_blk, dpa + copied,
1815 				iobuf + copied, c, rw, lane);
1816 		if (rc)
1817 			break;
1818 
1819 		copied += c;
1820 		len -= c;
1821 	}
1822 	nd_region_release_lane(nd_region, lane);
1823 
1824 	return rc;
1825 }
1826 
1827 static int nfit_blk_init_interleave(struct nfit_blk_mmio *mmio,
1828 		struct acpi_nfit_interleave *idt, u16 interleave_ways)
1829 {
1830 	if (idt) {
1831 		mmio->num_lines = idt->line_count;
1832 		mmio->line_size = idt->line_size;
1833 		if (interleave_ways == 0)
1834 			return -ENXIO;
1835 		mmio->table_size = mmio->num_lines * interleave_ways
1836 			* mmio->line_size;
1837 	}
1838 
1839 	return 0;
1840 }
1841 
1842 static int acpi_nfit_blk_get_flags(struct nvdimm_bus_descriptor *nd_desc,
1843 		struct nvdimm *nvdimm, struct nfit_blk *nfit_blk)
1844 {
1845 	struct nd_cmd_dimm_flags flags;
1846 	int rc;
1847 
1848 	memset(&flags, 0, sizeof(flags));
1849 	rc = nd_desc->ndctl(nd_desc, nvdimm, ND_CMD_DIMM_FLAGS, &flags,
1850 			sizeof(flags), NULL);
1851 
1852 	if (rc >= 0 && flags.status == 0)
1853 		nfit_blk->dimm_flags = flags.flags;
1854 	else if (rc == -ENOTTY) {
1855 		/* fall back to a conservative default */
1856 		nfit_blk->dimm_flags = NFIT_BLK_DCR_LATCH | NFIT_BLK_READ_FLUSH;
1857 		rc = 0;
1858 	} else
1859 		rc = -ENXIO;
1860 
1861 	return rc;
1862 }
1863 
1864 static int acpi_nfit_blk_region_enable(struct nvdimm_bus *nvdimm_bus,
1865 		struct device *dev)
1866 {
1867 	struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
1868 	struct nd_blk_region *ndbr = to_nd_blk_region(dev);
1869 	struct nfit_blk_mmio *mmio;
1870 	struct nfit_blk *nfit_blk;
1871 	struct nfit_mem *nfit_mem;
1872 	struct nvdimm *nvdimm;
1873 	int rc;
1874 
1875 	nvdimm = nd_blk_region_to_dimm(ndbr);
1876 	nfit_mem = nvdimm_provider_data(nvdimm);
1877 	if (!nfit_mem || !nfit_mem->dcr || !nfit_mem->bdw) {
1878 		dev_dbg(dev, "%s: missing%s%s%s\n", __func__,
1879 				nfit_mem ? "" : " nfit_mem",
1880 				(nfit_mem && nfit_mem->dcr) ? "" : " dcr",
1881 				(nfit_mem && nfit_mem->bdw) ? "" : " bdw");
1882 		return -ENXIO;
1883 	}
1884 
1885 	nfit_blk = devm_kzalloc(dev, sizeof(*nfit_blk), GFP_KERNEL);
1886 	if (!nfit_blk)
1887 		return -ENOMEM;
1888 	nd_blk_region_set_provider_data(ndbr, nfit_blk);
1889 	nfit_blk->nd_region = to_nd_region(dev);
1890 
1891 	/* map block aperture memory */
1892 	nfit_blk->bdw_offset = nfit_mem->bdw->offset;
1893 	mmio = &nfit_blk->mmio[BDW];
1894 	mmio->addr.base = devm_nvdimm_memremap(dev, nfit_mem->spa_bdw->address,
1895                         nfit_mem->spa_bdw->length, ARCH_MEMREMAP_PMEM);
1896 	if (!mmio->addr.base) {
1897 		dev_dbg(dev, "%s: %s failed to map bdw\n", __func__,
1898 				nvdimm_name(nvdimm));
1899 		return -ENOMEM;
1900 	}
1901 	mmio->size = nfit_mem->bdw->size;
1902 	mmio->base_offset = nfit_mem->memdev_bdw->region_offset;
1903 	mmio->idt = nfit_mem->idt_bdw;
1904 	mmio->spa = nfit_mem->spa_bdw;
1905 	rc = nfit_blk_init_interleave(mmio, nfit_mem->idt_bdw,
1906 			nfit_mem->memdev_bdw->interleave_ways);
1907 	if (rc) {
1908 		dev_dbg(dev, "%s: %s failed to init bdw interleave\n",
1909 				__func__, nvdimm_name(nvdimm));
1910 		return rc;
1911 	}
1912 
1913 	/* map block control memory */
1914 	nfit_blk->cmd_offset = nfit_mem->dcr->command_offset;
1915 	nfit_blk->stat_offset = nfit_mem->dcr->status_offset;
1916 	mmio = &nfit_blk->mmio[DCR];
1917 	mmio->addr.base = devm_nvdimm_ioremap(dev, nfit_mem->spa_dcr->address,
1918 			nfit_mem->spa_dcr->length);
1919 	if (!mmio->addr.base) {
1920 		dev_dbg(dev, "%s: %s failed to map dcr\n", __func__,
1921 				nvdimm_name(nvdimm));
1922 		return -ENOMEM;
1923 	}
1924 	mmio->size = nfit_mem->dcr->window_size;
1925 	mmio->base_offset = nfit_mem->memdev_dcr->region_offset;
1926 	mmio->idt = nfit_mem->idt_dcr;
1927 	mmio->spa = nfit_mem->spa_dcr;
1928 	rc = nfit_blk_init_interleave(mmio, nfit_mem->idt_dcr,
1929 			nfit_mem->memdev_dcr->interleave_ways);
1930 	if (rc) {
1931 		dev_dbg(dev, "%s: %s failed to init dcr interleave\n",
1932 				__func__, nvdimm_name(nvdimm));
1933 		return rc;
1934 	}
1935 
1936 	rc = acpi_nfit_blk_get_flags(nd_desc, nvdimm, nfit_blk);
1937 	if (rc < 0) {
1938 		dev_dbg(dev, "%s: %s failed get DIMM flags\n",
1939 				__func__, nvdimm_name(nvdimm));
1940 		return rc;
1941 	}
1942 
1943 	if (nvdimm_has_flush(nfit_blk->nd_region) < 0)
1944 		dev_warn(dev, "unable to guarantee persistence of writes\n");
1945 
1946 	if (mmio->line_size == 0)
1947 		return 0;
1948 
1949 	if ((u32) nfit_blk->cmd_offset % mmio->line_size
1950 			+ 8 > mmio->line_size) {
1951 		dev_dbg(dev, "cmd_offset crosses interleave boundary\n");
1952 		return -ENXIO;
1953 	} else if ((u32) nfit_blk->stat_offset % mmio->line_size
1954 			+ 8 > mmio->line_size) {
1955 		dev_dbg(dev, "stat_offset crosses interleave boundary\n");
1956 		return -ENXIO;
1957 	}
1958 
1959 	return 0;
1960 }
1961 
1962 static int ars_get_cap(struct acpi_nfit_desc *acpi_desc,
1963 		struct nd_cmd_ars_cap *cmd, struct nfit_spa *nfit_spa)
1964 {
1965 	struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
1966 	struct acpi_nfit_system_address *spa = nfit_spa->spa;
1967 	int cmd_rc, rc;
1968 
1969 	cmd->address = spa->address;
1970 	cmd->length = spa->length;
1971 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, cmd,
1972 			sizeof(*cmd), &cmd_rc);
1973 	if (rc < 0)
1974 		return rc;
1975 	return cmd_rc;
1976 }
1977 
1978 static int ars_start(struct acpi_nfit_desc *acpi_desc, struct nfit_spa *nfit_spa)
1979 {
1980 	int rc;
1981 	int cmd_rc;
1982 	struct nd_cmd_ars_start ars_start;
1983 	struct acpi_nfit_system_address *spa = nfit_spa->spa;
1984 	struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
1985 
1986 	memset(&ars_start, 0, sizeof(ars_start));
1987 	ars_start.address = spa->address;
1988 	ars_start.length = spa->length;
1989 	if (nfit_spa_type(spa) == NFIT_SPA_PM)
1990 		ars_start.type = ND_ARS_PERSISTENT;
1991 	else if (nfit_spa_type(spa) == NFIT_SPA_VOLATILE)
1992 		ars_start.type = ND_ARS_VOLATILE;
1993 	else
1994 		return -ENOTTY;
1995 
1996 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_START, &ars_start,
1997 			sizeof(ars_start), &cmd_rc);
1998 
1999 	if (rc < 0)
2000 		return rc;
2001 	return cmd_rc;
2002 }
2003 
2004 static int ars_continue(struct acpi_nfit_desc *acpi_desc)
2005 {
2006 	int rc, cmd_rc;
2007 	struct nd_cmd_ars_start ars_start;
2008 	struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
2009 	struct nd_cmd_ars_status *ars_status = acpi_desc->ars_status;
2010 
2011 	memset(&ars_start, 0, sizeof(ars_start));
2012 	ars_start.address = ars_status->restart_address;
2013 	ars_start.length = ars_status->restart_length;
2014 	ars_start.type = ars_status->type;
2015 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_START, &ars_start,
2016 			sizeof(ars_start), &cmd_rc);
2017 	if (rc < 0)
2018 		return rc;
2019 	return cmd_rc;
2020 }
2021 
2022 static int ars_get_status(struct acpi_nfit_desc *acpi_desc)
2023 {
2024 	struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
2025 	struct nd_cmd_ars_status *ars_status = acpi_desc->ars_status;
2026 	int rc, cmd_rc;
2027 
2028 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_STATUS, ars_status,
2029 			acpi_desc->ars_status_size, &cmd_rc);
2030 	if (rc < 0)
2031 		return rc;
2032 	return cmd_rc;
2033 }
2034 
2035 static int ars_status_process_records(struct acpi_nfit_desc *acpi_desc,
2036 		struct nd_cmd_ars_status *ars_status)
2037 {
2038 	struct nvdimm_bus *nvdimm_bus = acpi_desc->nvdimm_bus;
2039 	int rc;
2040 	u32 i;
2041 
2042 	/*
2043 	 * First record starts at 44 byte offset from the start of the
2044 	 * payload.
2045 	 */
2046 	if (ars_status->out_length < 44)
2047 		return 0;
2048 	for (i = 0; i < ars_status->num_records; i++) {
2049 		/* only process full records */
2050 		if (ars_status->out_length
2051 				< 44 + sizeof(struct nd_ars_record) * (i + 1))
2052 			break;
2053 		rc = nvdimm_bus_add_poison(nvdimm_bus,
2054 				ars_status->records[i].err_address,
2055 				ars_status->records[i].length);
2056 		if (rc)
2057 			return rc;
2058 	}
2059 	if (i < ars_status->num_records)
2060 		dev_warn(acpi_desc->dev, "detected truncated ars results\n");
2061 
2062 	return 0;
2063 }
2064 
2065 static void acpi_nfit_remove_resource(void *data)
2066 {
2067 	struct resource *res = data;
2068 
2069 	remove_resource(res);
2070 }
2071 
2072 static int acpi_nfit_insert_resource(struct acpi_nfit_desc *acpi_desc,
2073 		struct nd_region_desc *ndr_desc)
2074 {
2075 	struct resource *res, *nd_res = ndr_desc->res;
2076 	int is_pmem, ret;
2077 
2078 	/* No operation if the region is already registered as PMEM */
2079 	is_pmem = region_intersects(nd_res->start, resource_size(nd_res),
2080 				IORESOURCE_MEM, IORES_DESC_PERSISTENT_MEMORY);
2081 	if (is_pmem == REGION_INTERSECTS)
2082 		return 0;
2083 
2084 	res = devm_kzalloc(acpi_desc->dev, sizeof(*res), GFP_KERNEL);
2085 	if (!res)
2086 		return -ENOMEM;
2087 
2088 	res->name = "Persistent Memory";
2089 	res->start = nd_res->start;
2090 	res->end = nd_res->end;
2091 	res->flags = IORESOURCE_MEM;
2092 	res->desc = IORES_DESC_PERSISTENT_MEMORY;
2093 
2094 	ret = insert_resource(&iomem_resource, res);
2095 	if (ret)
2096 		return ret;
2097 
2098 	ret = devm_add_action_or_reset(acpi_desc->dev,
2099 					acpi_nfit_remove_resource,
2100 					res);
2101 	if (ret)
2102 		return ret;
2103 
2104 	return 0;
2105 }
2106 
2107 static int acpi_nfit_init_mapping(struct acpi_nfit_desc *acpi_desc,
2108 		struct nd_mapping_desc *mapping, struct nd_region_desc *ndr_desc,
2109 		struct acpi_nfit_memory_map *memdev,
2110 		struct nfit_spa *nfit_spa)
2111 {
2112 	struct nvdimm *nvdimm = acpi_nfit_dimm_by_handle(acpi_desc,
2113 			memdev->device_handle);
2114 	struct acpi_nfit_system_address *spa = nfit_spa->spa;
2115 	struct nd_blk_region_desc *ndbr_desc;
2116 	struct nfit_mem *nfit_mem;
2117 	int blk_valid = 0;
2118 
2119 	if (!nvdimm) {
2120 		dev_err(acpi_desc->dev, "spa%d dimm: %#x not found\n",
2121 				spa->range_index, memdev->device_handle);
2122 		return -ENODEV;
2123 	}
2124 
2125 	mapping->nvdimm = nvdimm;
2126 	switch (nfit_spa_type(spa)) {
2127 	case NFIT_SPA_PM:
2128 	case NFIT_SPA_VOLATILE:
2129 		mapping->start = memdev->address;
2130 		mapping->size = memdev->region_size;
2131 		break;
2132 	case NFIT_SPA_DCR:
2133 		nfit_mem = nvdimm_provider_data(nvdimm);
2134 		if (!nfit_mem || !nfit_mem->bdw) {
2135 			dev_dbg(acpi_desc->dev, "spa%d %s missing bdw\n",
2136 					spa->range_index, nvdimm_name(nvdimm));
2137 		} else {
2138 			mapping->size = nfit_mem->bdw->capacity;
2139 			mapping->start = nfit_mem->bdw->start_address;
2140 			ndr_desc->num_lanes = nfit_mem->bdw->windows;
2141 			blk_valid = 1;
2142 		}
2143 
2144 		ndr_desc->mapping = mapping;
2145 		ndr_desc->num_mappings = blk_valid;
2146 		ndbr_desc = to_blk_region_desc(ndr_desc);
2147 		ndbr_desc->enable = acpi_nfit_blk_region_enable;
2148 		ndbr_desc->do_io = acpi_desc->blk_do_io;
2149 		nfit_spa->nd_region = nvdimm_blk_region_create(acpi_desc->nvdimm_bus,
2150 				ndr_desc);
2151 		if (!nfit_spa->nd_region)
2152 			return -ENOMEM;
2153 		break;
2154 	}
2155 
2156 	return 0;
2157 }
2158 
2159 static bool nfit_spa_is_virtual(struct acpi_nfit_system_address *spa)
2160 {
2161 	return (nfit_spa_type(spa) == NFIT_SPA_VDISK ||
2162 		nfit_spa_type(spa) == NFIT_SPA_VCD   ||
2163 		nfit_spa_type(spa) == NFIT_SPA_PDISK ||
2164 		nfit_spa_type(spa) == NFIT_SPA_PCD);
2165 }
2166 
2167 static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc,
2168 		struct nfit_spa *nfit_spa)
2169 {
2170 	static struct nd_mapping_desc mappings[ND_MAX_MAPPINGS];
2171 	struct acpi_nfit_system_address *spa = nfit_spa->spa;
2172 	struct nd_blk_region_desc ndbr_desc;
2173 	struct nd_region_desc *ndr_desc;
2174 	struct nfit_memdev *nfit_memdev;
2175 	struct nvdimm_bus *nvdimm_bus;
2176 	struct resource res;
2177 	int count = 0, rc;
2178 
2179 	if (nfit_spa->nd_region)
2180 		return 0;
2181 
2182 	if (spa->range_index == 0 && !nfit_spa_is_virtual(spa)) {
2183 		dev_dbg(acpi_desc->dev, "%s: detected invalid spa index\n",
2184 				__func__);
2185 		return 0;
2186 	}
2187 
2188 	memset(&res, 0, sizeof(res));
2189 	memset(&mappings, 0, sizeof(mappings));
2190 	memset(&ndbr_desc, 0, sizeof(ndbr_desc));
2191 	res.start = spa->address;
2192 	res.end = res.start + spa->length - 1;
2193 	ndr_desc = &ndbr_desc.ndr_desc;
2194 	ndr_desc->res = &res;
2195 	ndr_desc->provider_data = nfit_spa;
2196 	ndr_desc->attr_groups = acpi_nfit_region_attribute_groups;
2197 	if (spa->flags & ACPI_NFIT_PROXIMITY_VALID)
2198 		ndr_desc->numa_node = acpi_map_pxm_to_online_node(
2199 						spa->proximity_domain);
2200 	else
2201 		ndr_desc->numa_node = NUMA_NO_NODE;
2202 
2203 	list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) {
2204 		struct acpi_nfit_memory_map *memdev = nfit_memdev->memdev;
2205 		struct nd_mapping_desc *mapping;
2206 
2207 		if (memdev->range_index != spa->range_index)
2208 			continue;
2209 		if (count >= ND_MAX_MAPPINGS) {
2210 			dev_err(acpi_desc->dev, "spa%d exceeds max mappings %d\n",
2211 					spa->range_index, ND_MAX_MAPPINGS);
2212 			return -ENXIO;
2213 		}
2214 		mapping = &mappings[count++];
2215 		rc = acpi_nfit_init_mapping(acpi_desc, mapping, ndr_desc,
2216 				memdev, nfit_spa);
2217 		if (rc)
2218 			goto out;
2219 	}
2220 
2221 	ndr_desc->mapping = mappings;
2222 	ndr_desc->num_mappings = count;
2223 	rc = acpi_nfit_init_interleave_set(acpi_desc, ndr_desc, spa);
2224 	if (rc)
2225 		goto out;
2226 
2227 	nvdimm_bus = acpi_desc->nvdimm_bus;
2228 	if (nfit_spa_type(spa) == NFIT_SPA_PM) {
2229 		rc = acpi_nfit_insert_resource(acpi_desc, ndr_desc);
2230 		if (rc) {
2231 			dev_warn(acpi_desc->dev,
2232 				"failed to insert pmem resource to iomem: %d\n",
2233 				rc);
2234 			goto out;
2235 		}
2236 
2237 		nfit_spa->nd_region = nvdimm_pmem_region_create(nvdimm_bus,
2238 				ndr_desc);
2239 		if (!nfit_spa->nd_region)
2240 			rc = -ENOMEM;
2241 	} else if (nfit_spa_type(spa) == NFIT_SPA_VOLATILE) {
2242 		nfit_spa->nd_region = nvdimm_volatile_region_create(nvdimm_bus,
2243 				ndr_desc);
2244 		if (!nfit_spa->nd_region)
2245 			rc = -ENOMEM;
2246 	} else if (nfit_spa_is_virtual(spa)) {
2247 		nfit_spa->nd_region = nvdimm_pmem_region_create(nvdimm_bus,
2248 				ndr_desc);
2249 		if (!nfit_spa->nd_region)
2250 			rc = -ENOMEM;
2251 	}
2252 
2253  out:
2254 	if (rc)
2255 		dev_err(acpi_desc->dev, "failed to register spa range %d\n",
2256 				nfit_spa->spa->range_index);
2257 	return rc;
2258 }
2259 
2260 static int ars_status_alloc(struct acpi_nfit_desc *acpi_desc,
2261 		u32 max_ars)
2262 {
2263 	struct device *dev = acpi_desc->dev;
2264 	struct nd_cmd_ars_status *ars_status;
2265 
2266 	if (acpi_desc->ars_status && acpi_desc->ars_status_size >= max_ars) {
2267 		memset(acpi_desc->ars_status, 0, acpi_desc->ars_status_size);
2268 		return 0;
2269 	}
2270 
2271 	if (acpi_desc->ars_status)
2272 		devm_kfree(dev, acpi_desc->ars_status);
2273 	acpi_desc->ars_status = NULL;
2274 	ars_status = devm_kzalloc(dev, max_ars, GFP_KERNEL);
2275 	if (!ars_status)
2276 		return -ENOMEM;
2277 	acpi_desc->ars_status = ars_status;
2278 	acpi_desc->ars_status_size = max_ars;
2279 	return 0;
2280 }
2281 
2282 static int acpi_nfit_query_poison(struct acpi_nfit_desc *acpi_desc,
2283 		struct nfit_spa *nfit_spa)
2284 {
2285 	struct acpi_nfit_system_address *spa = nfit_spa->spa;
2286 	int rc;
2287 
2288 	if (!nfit_spa->max_ars) {
2289 		struct nd_cmd_ars_cap ars_cap;
2290 
2291 		memset(&ars_cap, 0, sizeof(ars_cap));
2292 		rc = ars_get_cap(acpi_desc, &ars_cap, nfit_spa);
2293 		if (rc < 0)
2294 			return rc;
2295 		nfit_spa->max_ars = ars_cap.max_ars_out;
2296 		nfit_spa->clear_err_unit = ars_cap.clear_err_unit;
2297 		/* check that the supported scrub types match the spa type */
2298 		if (nfit_spa_type(spa) == NFIT_SPA_VOLATILE &&
2299 				((ars_cap.status >> 16) & ND_ARS_VOLATILE) == 0)
2300 			return -ENOTTY;
2301 		else if (nfit_spa_type(spa) == NFIT_SPA_PM &&
2302 				((ars_cap.status >> 16) & ND_ARS_PERSISTENT) == 0)
2303 			return -ENOTTY;
2304 	}
2305 
2306 	if (ars_status_alloc(acpi_desc, nfit_spa->max_ars))
2307 		return -ENOMEM;
2308 
2309 	rc = ars_get_status(acpi_desc);
2310 	if (rc < 0 && rc != -ENOSPC)
2311 		return rc;
2312 
2313 	if (ars_status_process_records(acpi_desc, acpi_desc->ars_status))
2314 		return -ENOMEM;
2315 
2316 	return 0;
2317 }
2318 
2319 static void acpi_nfit_async_scrub(struct acpi_nfit_desc *acpi_desc,
2320 		struct nfit_spa *nfit_spa)
2321 {
2322 	struct acpi_nfit_system_address *spa = nfit_spa->spa;
2323 	unsigned int overflow_retry = scrub_overflow_abort;
2324 	u64 init_ars_start = 0, init_ars_len = 0;
2325 	struct device *dev = acpi_desc->dev;
2326 	unsigned int tmo = scrub_timeout;
2327 	int rc;
2328 
2329 	if (!nfit_spa->ars_required || !nfit_spa->nd_region)
2330 		return;
2331 
2332 	rc = ars_start(acpi_desc, nfit_spa);
2333 	/*
2334 	 * If we timed out the initial scan we'll still be busy here,
2335 	 * and will wait another timeout before giving up permanently.
2336 	 */
2337 	if (rc < 0 && rc != -EBUSY)
2338 		return;
2339 
2340 	do {
2341 		u64 ars_start, ars_len;
2342 
2343 		if (acpi_desc->cancel)
2344 			break;
2345 		rc = acpi_nfit_query_poison(acpi_desc, nfit_spa);
2346 		if (rc == -ENOTTY)
2347 			break;
2348 		if (rc == -EBUSY && !tmo) {
2349 			dev_warn(dev, "range %d ars timeout, aborting\n",
2350 					spa->range_index);
2351 			break;
2352 		}
2353 
2354 		if (rc == -EBUSY) {
2355 			/*
2356 			 * Note, entries may be appended to the list
2357 			 * while the lock is dropped, but the workqueue
2358 			 * being active prevents entries being deleted /
2359 			 * freed.
2360 			 */
2361 			mutex_unlock(&acpi_desc->init_mutex);
2362 			ssleep(1);
2363 			tmo--;
2364 			mutex_lock(&acpi_desc->init_mutex);
2365 			continue;
2366 		}
2367 
2368 		/* we got some results, but there are more pending... */
2369 		if (rc == -ENOSPC && overflow_retry--) {
2370 			if (!init_ars_len) {
2371 				init_ars_len = acpi_desc->ars_status->length;
2372 				init_ars_start = acpi_desc->ars_status->address;
2373 			}
2374 			rc = ars_continue(acpi_desc);
2375 		}
2376 
2377 		if (rc < 0) {
2378 			dev_warn(dev, "range %d ars continuation failed\n",
2379 					spa->range_index);
2380 			break;
2381 		}
2382 
2383 		if (init_ars_len) {
2384 			ars_start = init_ars_start;
2385 			ars_len = init_ars_len;
2386 		} else {
2387 			ars_start = acpi_desc->ars_status->address;
2388 			ars_len = acpi_desc->ars_status->length;
2389 		}
2390 		dev_dbg(dev, "spa range: %d ars from %#llx + %#llx complete\n",
2391 				spa->range_index, ars_start, ars_len);
2392 		/* notify the region about new poison entries */
2393 		nvdimm_region_notify(nfit_spa->nd_region,
2394 				NVDIMM_REVALIDATE_POISON);
2395 		break;
2396 	} while (1);
2397 }
2398 
2399 static void acpi_nfit_scrub(struct work_struct *work)
2400 {
2401 	struct device *dev;
2402 	u64 init_scrub_length = 0;
2403 	struct nfit_spa *nfit_spa;
2404 	u64 init_scrub_address = 0;
2405 	bool init_ars_done = false;
2406 	struct acpi_nfit_desc *acpi_desc;
2407 	unsigned int tmo = scrub_timeout;
2408 	unsigned int overflow_retry = scrub_overflow_abort;
2409 
2410 	acpi_desc = container_of(work, typeof(*acpi_desc), work);
2411 	dev = acpi_desc->dev;
2412 
2413 	/*
2414 	 * We scrub in 2 phases.  The first phase waits for any platform
2415 	 * firmware initiated scrubs to complete and then we go search for the
2416 	 * affected spa regions to mark them scanned.  In the second phase we
2417 	 * initiate a directed scrub for every range that was not scrubbed in
2418 	 * phase 1. If we're called for a 'rescan', we harmlessly pass through
2419 	 * the first phase, but really only care about running phase 2, where
2420 	 * regions can be notified of new poison.
2421 	 */
2422 
2423 	/* process platform firmware initiated scrubs */
2424  retry:
2425 	mutex_lock(&acpi_desc->init_mutex);
2426 	list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
2427 		struct nd_cmd_ars_status *ars_status;
2428 		struct acpi_nfit_system_address *spa;
2429 		u64 ars_start, ars_len;
2430 		int rc;
2431 
2432 		if (acpi_desc->cancel)
2433 			break;
2434 
2435 		if (nfit_spa->nd_region)
2436 			continue;
2437 
2438 		if (init_ars_done) {
2439 			/*
2440 			 * No need to re-query, we're now just
2441 			 * reconciling all the ranges covered by the
2442 			 * initial scrub
2443 			 */
2444 			rc = 0;
2445 		} else
2446 			rc = acpi_nfit_query_poison(acpi_desc, nfit_spa);
2447 
2448 		if (rc == -ENOTTY) {
2449 			/* no ars capability, just register spa and move on */
2450 			acpi_nfit_register_region(acpi_desc, nfit_spa);
2451 			continue;
2452 		}
2453 
2454 		if (rc == -EBUSY && !tmo) {
2455 			/* fallthrough to directed scrub in phase 2 */
2456 			dev_warn(dev, "timeout awaiting ars results, continuing...\n");
2457 			break;
2458 		} else if (rc == -EBUSY) {
2459 			mutex_unlock(&acpi_desc->init_mutex);
2460 			ssleep(1);
2461 			tmo--;
2462 			goto retry;
2463 		}
2464 
2465 		/* we got some results, but there are more pending... */
2466 		if (rc == -ENOSPC && overflow_retry--) {
2467 			ars_status = acpi_desc->ars_status;
2468 			/*
2469 			 * Record the original scrub range, so that we
2470 			 * can recall all the ranges impacted by the
2471 			 * initial scrub.
2472 			 */
2473 			if (!init_scrub_length) {
2474 				init_scrub_length = ars_status->length;
2475 				init_scrub_address = ars_status->address;
2476 			}
2477 			rc = ars_continue(acpi_desc);
2478 			if (rc == 0) {
2479 				mutex_unlock(&acpi_desc->init_mutex);
2480 				goto retry;
2481 			}
2482 		}
2483 
2484 		if (rc < 0) {
2485 			/*
2486 			 * Initial scrub failed, we'll give it one more
2487 			 * try below...
2488 			 */
2489 			break;
2490 		}
2491 
2492 		/* We got some final results, record completed ranges */
2493 		ars_status = acpi_desc->ars_status;
2494 		if (init_scrub_length) {
2495 			ars_start = init_scrub_address;
2496 			ars_len = ars_start + init_scrub_length;
2497 		} else {
2498 			ars_start = ars_status->address;
2499 			ars_len = ars_status->length;
2500 		}
2501 		spa = nfit_spa->spa;
2502 
2503 		if (!init_ars_done) {
2504 			init_ars_done = true;
2505 			dev_dbg(dev, "init scrub %#llx + %#llx complete\n",
2506 					ars_start, ars_len);
2507 		}
2508 		if (ars_start <= spa->address && ars_start + ars_len
2509 				>= spa->address + spa->length)
2510 			acpi_nfit_register_region(acpi_desc, nfit_spa);
2511 	}
2512 
2513 	/*
2514 	 * For all the ranges not covered by an initial scrub we still
2515 	 * want to see if there are errors, but it's ok to discover them
2516 	 * asynchronously.
2517 	 */
2518 	list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
2519 		/*
2520 		 * Flag all the ranges that still need scrubbing, but
2521 		 * register them now to make data available.
2522 		 */
2523 		if (!nfit_spa->nd_region) {
2524 			nfit_spa->ars_required = 1;
2525 			acpi_nfit_register_region(acpi_desc, nfit_spa);
2526 		}
2527 	}
2528 
2529 	list_for_each_entry(nfit_spa, &acpi_desc->spas, list)
2530 		acpi_nfit_async_scrub(acpi_desc, nfit_spa);
2531 	acpi_desc->scrub_count++;
2532 	if (acpi_desc->scrub_count_state)
2533 		sysfs_notify_dirent(acpi_desc->scrub_count_state);
2534 	mutex_unlock(&acpi_desc->init_mutex);
2535 }
2536 
2537 static int acpi_nfit_register_regions(struct acpi_nfit_desc *acpi_desc)
2538 {
2539 	struct nfit_spa *nfit_spa;
2540 	int rc;
2541 
2542 	list_for_each_entry(nfit_spa, &acpi_desc->spas, list)
2543 		if (nfit_spa_type(nfit_spa->spa) == NFIT_SPA_DCR) {
2544 			/* BLK regions don't need to wait for ars results */
2545 			rc = acpi_nfit_register_region(acpi_desc, nfit_spa);
2546 			if (rc)
2547 				return rc;
2548 		}
2549 
2550 	queue_work(nfit_wq, &acpi_desc->work);
2551 	return 0;
2552 }
2553 
2554 static int acpi_nfit_check_deletions(struct acpi_nfit_desc *acpi_desc,
2555 		struct nfit_table_prev *prev)
2556 {
2557 	struct device *dev = acpi_desc->dev;
2558 
2559 	if (!list_empty(&prev->spas) ||
2560 			!list_empty(&prev->memdevs) ||
2561 			!list_empty(&prev->dcrs) ||
2562 			!list_empty(&prev->bdws) ||
2563 			!list_empty(&prev->idts) ||
2564 			!list_empty(&prev->flushes)) {
2565 		dev_err(dev, "new nfit deletes entries (unsupported)\n");
2566 		return -ENXIO;
2567 	}
2568 	return 0;
2569 }
2570 
2571 static int acpi_nfit_desc_init_scrub_attr(struct acpi_nfit_desc *acpi_desc)
2572 {
2573 	struct device *dev = acpi_desc->dev;
2574 	struct kernfs_node *nfit;
2575 	struct device *bus_dev;
2576 
2577 	if (!ars_supported(acpi_desc->nvdimm_bus))
2578 		return 0;
2579 
2580 	bus_dev = to_nvdimm_bus_dev(acpi_desc->nvdimm_bus);
2581 	nfit = sysfs_get_dirent(bus_dev->kobj.sd, "nfit");
2582 	if (!nfit) {
2583 		dev_err(dev, "sysfs_get_dirent 'nfit' failed\n");
2584 		return -ENODEV;
2585 	}
2586 	acpi_desc->scrub_count_state = sysfs_get_dirent(nfit, "scrub");
2587 	sysfs_put(nfit);
2588 	if (!acpi_desc->scrub_count_state) {
2589 		dev_err(dev, "sysfs_get_dirent 'scrub' failed\n");
2590 		return -ENODEV;
2591 	}
2592 
2593 	return 0;
2594 }
2595 
2596 static void acpi_nfit_destruct(void *data)
2597 {
2598 	struct acpi_nfit_desc *acpi_desc = data;
2599 	struct device *bus_dev = to_nvdimm_bus_dev(acpi_desc->nvdimm_bus);
2600 
2601 	/*
2602 	 * Destruct under acpi_desc_lock so that nfit_handle_mce does not
2603 	 * race teardown
2604 	 */
2605 	mutex_lock(&acpi_desc_lock);
2606 	acpi_desc->cancel = 1;
2607 	/*
2608 	 * Bounce the nvdimm bus lock to make sure any in-flight
2609 	 * acpi_nfit_ars_rescan() submissions have had a chance to
2610 	 * either submit or see ->cancel set.
2611 	 */
2612 	device_lock(bus_dev);
2613 	device_unlock(bus_dev);
2614 
2615 	flush_workqueue(nfit_wq);
2616 	if (acpi_desc->scrub_count_state)
2617 		sysfs_put(acpi_desc->scrub_count_state);
2618 	nvdimm_bus_unregister(acpi_desc->nvdimm_bus);
2619 	acpi_desc->nvdimm_bus = NULL;
2620 	list_del(&acpi_desc->list);
2621 	mutex_unlock(&acpi_desc_lock);
2622 }
2623 
2624 int acpi_nfit_init(struct acpi_nfit_desc *acpi_desc, void *data, acpi_size sz)
2625 {
2626 	struct device *dev = acpi_desc->dev;
2627 	struct nfit_table_prev prev;
2628 	const void *end;
2629 	int rc;
2630 
2631 	if (!acpi_desc->nvdimm_bus) {
2632 		acpi_nfit_init_dsms(acpi_desc);
2633 
2634 		acpi_desc->nvdimm_bus = nvdimm_bus_register(dev,
2635 				&acpi_desc->nd_desc);
2636 		if (!acpi_desc->nvdimm_bus)
2637 			return -ENOMEM;
2638 
2639 		rc = devm_add_action_or_reset(dev, acpi_nfit_destruct,
2640 				acpi_desc);
2641 		if (rc)
2642 			return rc;
2643 
2644 		rc = acpi_nfit_desc_init_scrub_attr(acpi_desc);
2645 		if (rc)
2646 			return rc;
2647 
2648 		/* register this acpi_desc for mce notifications */
2649 		mutex_lock(&acpi_desc_lock);
2650 		list_add_tail(&acpi_desc->list, &acpi_descs);
2651 		mutex_unlock(&acpi_desc_lock);
2652 	}
2653 
2654 	mutex_lock(&acpi_desc->init_mutex);
2655 
2656 	INIT_LIST_HEAD(&prev.spas);
2657 	INIT_LIST_HEAD(&prev.memdevs);
2658 	INIT_LIST_HEAD(&prev.dcrs);
2659 	INIT_LIST_HEAD(&prev.bdws);
2660 	INIT_LIST_HEAD(&prev.idts);
2661 	INIT_LIST_HEAD(&prev.flushes);
2662 
2663 	list_cut_position(&prev.spas, &acpi_desc->spas,
2664 				acpi_desc->spas.prev);
2665 	list_cut_position(&prev.memdevs, &acpi_desc->memdevs,
2666 				acpi_desc->memdevs.prev);
2667 	list_cut_position(&prev.dcrs, &acpi_desc->dcrs,
2668 				acpi_desc->dcrs.prev);
2669 	list_cut_position(&prev.bdws, &acpi_desc->bdws,
2670 				acpi_desc->bdws.prev);
2671 	list_cut_position(&prev.idts, &acpi_desc->idts,
2672 				acpi_desc->idts.prev);
2673 	list_cut_position(&prev.flushes, &acpi_desc->flushes,
2674 				acpi_desc->flushes.prev);
2675 
2676 	end = data + sz;
2677 	while (!IS_ERR_OR_NULL(data))
2678 		data = add_table(acpi_desc, &prev, data, end);
2679 
2680 	if (IS_ERR(data)) {
2681 		dev_dbg(dev, "%s: nfit table parsing error: %ld\n", __func__,
2682 				PTR_ERR(data));
2683 		rc = PTR_ERR(data);
2684 		goto out_unlock;
2685 	}
2686 
2687 	rc = acpi_nfit_check_deletions(acpi_desc, &prev);
2688 	if (rc)
2689 		goto out_unlock;
2690 
2691 	rc = nfit_mem_init(acpi_desc);
2692 	if (rc)
2693 		goto out_unlock;
2694 
2695 	rc = acpi_nfit_register_dimms(acpi_desc);
2696 	if (rc)
2697 		goto out_unlock;
2698 
2699 	rc = acpi_nfit_register_regions(acpi_desc);
2700 
2701  out_unlock:
2702 	mutex_unlock(&acpi_desc->init_mutex);
2703 	return rc;
2704 }
2705 EXPORT_SYMBOL_GPL(acpi_nfit_init);
2706 
2707 struct acpi_nfit_flush_work {
2708 	struct work_struct work;
2709 	struct completion cmp;
2710 };
2711 
2712 static void flush_probe(struct work_struct *work)
2713 {
2714 	struct acpi_nfit_flush_work *flush;
2715 
2716 	flush = container_of(work, typeof(*flush), work);
2717 	complete(&flush->cmp);
2718 }
2719 
2720 static int acpi_nfit_flush_probe(struct nvdimm_bus_descriptor *nd_desc)
2721 {
2722 	struct acpi_nfit_desc *acpi_desc = to_acpi_nfit_desc(nd_desc);
2723 	struct device *dev = acpi_desc->dev;
2724 	struct acpi_nfit_flush_work flush;
2725 	int rc;
2726 
2727 	/* bounce the device lock to flush acpi_nfit_add / acpi_nfit_notify */
2728 	device_lock(dev);
2729 	device_unlock(dev);
2730 
2731 	/*
2732 	 * Scrub work could take 10s of seconds, userspace may give up so we
2733 	 * need to be interruptible while waiting.
2734 	 */
2735 	INIT_WORK_ONSTACK(&flush.work, flush_probe);
2736 	COMPLETION_INITIALIZER_ONSTACK(flush.cmp);
2737 	queue_work(nfit_wq, &flush.work);
2738 
2739 	rc = wait_for_completion_interruptible(&flush.cmp);
2740 	cancel_work_sync(&flush.work);
2741 	return rc;
2742 }
2743 
2744 static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
2745 		struct nvdimm *nvdimm, unsigned int cmd)
2746 {
2747 	struct acpi_nfit_desc *acpi_desc = to_acpi_nfit_desc(nd_desc);
2748 
2749 	if (nvdimm)
2750 		return 0;
2751 	if (cmd != ND_CMD_ARS_START)
2752 		return 0;
2753 
2754 	/*
2755 	 * The kernel and userspace may race to initiate a scrub, but
2756 	 * the scrub thread is prepared to lose that initial race.  It
2757 	 * just needs guarantees that any ars it initiates are not
2758 	 * interrupted by any intervening start reqeusts from userspace.
2759 	 */
2760 	if (work_busy(&acpi_desc->work))
2761 		return -EBUSY;
2762 
2763 	return 0;
2764 }
2765 
2766 int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc)
2767 {
2768 	struct device *dev = acpi_desc->dev;
2769 	struct nfit_spa *nfit_spa;
2770 
2771 	if (work_busy(&acpi_desc->work))
2772 		return -EBUSY;
2773 
2774 	if (acpi_desc->cancel)
2775 		return 0;
2776 
2777 	mutex_lock(&acpi_desc->init_mutex);
2778 	list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
2779 		struct acpi_nfit_system_address *spa = nfit_spa->spa;
2780 
2781 		if (nfit_spa_type(spa) != NFIT_SPA_PM)
2782 			continue;
2783 
2784 		nfit_spa->ars_required = 1;
2785 	}
2786 	queue_work(nfit_wq, &acpi_desc->work);
2787 	dev_dbg(dev, "%s: ars_scan triggered\n", __func__);
2788 	mutex_unlock(&acpi_desc->init_mutex);
2789 
2790 	return 0;
2791 }
2792 
2793 void acpi_nfit_desc_init(struct acpi_nfit_desc *acpi_desc, struct device *dev)
2794 {
2795 	struct nvdimm_bus_descriptor *nd_desc;
2796 
2797 	dev_set_drvdata(dev, acpi_desc);
2798 	acpi_desc->dev = dev;
2799 	acpi_desc->blk_do_io = acpi_nfit_blk_region_do_io;
2800 	nd_desc = &acpi_desc->nd_desc;
2801 	nd_desc->provider_name = "ACPI.NFIT";
2802 	nd_desc->module = THIS_MODULE;
2803 	nd_desc->ndctl = acpi_nfit_ctl;
2804 	nd_desc->flush_probe = acpi_nfit_flush_probe;
2805 	nd_desc->clear_to_send = acpi_nfit_clear_to_send;
2806 	nd_desc->attr_groups = acpi_nfit_attribute_groups;
2807 
2808 	INIT_LIST_HEAD(&acpi_desc->spas);
2809 	INIT_LIST_HEAD(&acpi_desc->dcrs);
2810 	INIT_LIST_HEAD(&acpi_desc->bdws);
2811 	INIT_LIST_HEAD(&acpi_desc->idts);
2812 	INIT_LIST_HEAD(&acpi_desc->flushes);
2813 	INIT_LIST_HEAD(&acpi_desc->memdevs);
2814 	INIT_LIST_HEAD(&acpi_desc->dimms);
2815 	INIT_LIST_HEAD(&acpi_desc->list);
2816 	mutex_init(&acpi_desc->init_mutex);
2817 	INIT_WORK(&acpi_desc->work, acpi_nfit_scrub);
2818 }
2819 EXPORT_SYMBOL_GPL(acpi_nfit_desc_init);
2820 
2821 static int acpi_nfit_add(struct acpi_device *adev)
2822 {
2823 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
2824 	struct acpi_nfit_desc *acpi_desc;
2825 	struct device *dev = &adev->dev;
2826 	struct acpi_table_header *tbl;
2827 	acpi_status status = AE_OK;
2828 	acpi_size sz;
2829 	int rc = 0;
2830 
2831 	status = acpi_get_table(ACPI_SIG_NFIT, 0, &tbl);
2832 	if (ACPI_FAILURE(status)) {
2833 		/* This is ok, we could have an nvdimm hotplugged later */
2834 		dev_dbg(dev, "failed to find NFIT at startup\n");
2835 		return 0;
2836 	}
2837 	sz = tbl->length;
2838 
2839 	acpi_desc = devm_kzalloc(dev, sizeof(*acpi_desc), GFP_KERNEL);
2840 	if (!acpi_desc)
2841 		return -ENOMEM;
2842 	acpi_nfit_desc_init(acpi_desc, &adev->dev);
2843 
2844 	/* Save the acpi header for exporting the revision via sysfs */
2845 	acpi_desc->acpi_header = *tbl;
2846 
2847 	/* Evaluate _FIT and override with that if present */
2848 	status = acpi_evaluate_object(adev->handle, "_FIT", NULL, &buf);
2849 	if (ACPI_SUCCESS(status) && buf.length > 0) {
2850 		union acpi_object *obj = buf.pointer;
2851 
2852 		if (obj->type == ACPI_TYPE_BUFFER)
2853 			rc = acpi_nfit_init(acpi_desc, obj->buffer.pointer,
2854 					obj->buffer.length);
2855 		else
2856 			dev_dbg(dev, "%s invalid type %d, ignoring _FIT\n",
2857 				 __func__, (int) obj->type);
2858 		kfree(buf.pointer);
2859 	} else
2860 		/* skip over the lead-in header table */
2861 		rc = acpi_nfit_init(acpi_desc, (void *) tbl
2862 				+ sizeof(struct acpi_table_nfit),
2863 				sz - sizeof(struct acpi_table_nfit));
2864 	return rc;
2865 }
2866 
2867 static int acpi_nfit_remove(struct acpi_device *adev)
2868 {
2869 	/* see acpi_nfit_destruct */
2870 	return 0;
2871 }
2872 
2873 void __acpi_nfit_notify(struct device *dev, acpi_handle handle, u32 event)
2874 {
2875 	struct acpi_nfit_desc *acpi_desc = dev_get_drvdata(dev);
2876 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
2877 	union acpi_object *obj;
2878 	acpi_status status;
2879 	int ret;
2880 
2881 	dev_dbg(dev, "%s: event: %d\n", __func__, event);
2882 
2883 	if (event != NFIT_NOTIFY_UPDATE)
2884 		return;
2885 
2886 	if (!dev->driver) {
2887 		/* dev->driver may be null if we're being removed */
2888 		dev_dbg(dev, "%s: no driver found for dev\n", __func__);
2889 		return;
2890 	}
2891 
2892 	if (!acpi_desc) {
2893 		acpi_desc = devm_kzalloc(dev, sizeof(*acpi_desc), GFP_KERNEL);
2894 		if (!acpi_desc)
2895 			return;
2896 		acpi_nfit_desc_init(acpi_desc, dev);
2897 	} else {
2898 		/*
2899 		 * Finish previous registration before considering new
2900 		 * regions.
2901 		 */
2902 		flush_workqueue(nfit_wq);
2903 	}
2904 
2905 	/* Evaluate _FIT */
2906 	status = acpi_evaluate_object(handle, "_FIT", NULL, &buf);
2907 	if (ACPI_FAILURE(status)) {
2908 		dev_err(dev, "failed to evaluate _FIT\n");
2909 		return;
2910 	}
2911 
2912 	obj = buf.pointer;
2913 	if (obj->type == ACPI_TYPE_BUFFER) {
2914 		ret = acpi_nfit_init(acpi_desc, obj->buffer.pointer,
2915 				obj->buffer.length);
2916 		if (ret)
2917 			dev_err(dev, "failed to merge updated NFIT\n");
2918 	} else
2919 		dev_err(dev, "Invalid _FIT\n");
2920 	kfree(buf.pointer);
2921 }
2922 EXPORT_SYMBOL_GPL(__acpi_nfit_notify);
2923 
2924 static void acpi_nfit_notify(struct acpi_device *adev, u32 event)
2925 {
2926 	device_lock(&adev->dev);
2927 	__acpi_nfit_notify(&adev->dev, adev->handle, event);
2928 	device_unlock(&adev->dev);
2929 }
2930 
2931 static const struct acpi_device_id acpi_nfit_ids[] = {
2932 	{ "ACPI0012", 0 },
2933 	{ "", 0 },
2934 };
2935 MODULE_DEVICE_TABLE(acpi, acpi_nfit_ids);
2936 
2937 static struct acpi_driver acpi_nfit_driver = {
2938 	.name = KBUILD_MODNAME,
2939 	.ids = acpi_nfit_ids,
2940 	.ops = {
2941 		.add = acpi_nfit_add,
2942 		.remove = acpi_nfit_remove,
2943 		.notify = acpi_nfit_notify,
2944 	},
2945 };
2946 
2947 static __init int nfit_init(void)
2948 {
2949 	BUILD_BUG_ON(sizeof(struct acpi_table_nfit) != 40);
2950 	BUILD_BUG_ON(sizeof(struct acpi_nfit_system_address) != 56);
2951 	BUILD_BUG_ON(sizeof(struct acpi_nfit_memory_map) != 48);
2952 	BUILD_BUG_ON(sizeof(struct acpi_nfit_interleave) != 20);
2953 	BUILD_BUG_ON(sizeof(struct acpi_nfit_smbios) != 9);
2954 	BUILD_BUG_ON(sizeof(struct acpi_nfit_control_region) != 80);
2955 	BUILD_BUG_ON(sizeof(struct acpi_nfit_data_region) != 40);
2956 
2957 	acpi_str_to_uuid(UUID_VOLATILE_MEMORY, nfit_uuid[NFIT_SPA_VOLATILE]);
2958 	acpi_str_to_uuid(UUID_PERSISTENT_MEMORY, nfit_uuid[NFIT_SPA_PM]);
2959 	acpi_str_to_uuid(UUID_CONTROL_REGION, nfit_uuid[NFIT_SPA_DCR]);
2960 	acpi_str_to_uuid(UUID_DATA_REGION, nfit_uuid[NFIT_SPA_BDW]);
2961 	acpi_str_to_uuid(UUID_VOLATILE_VIRTUAL_DISK, nfit_uuid[NFIT_SPA_VDISK]);
2962 	acpi_str_to_uuid(UUID_VOLATILE_VIRTUAL_CD, nfit_uuid[NFIT_SPA_VCD]);
2963 	acpi_str_to_uuid(UUID_PERSISTENT_VIRTUAL_DISK, nfit_uuid[NFIT_SPA_PDISK]);
2964 	acpi_str_to_uuid(UUID_PERSISTENT_VIRTUAL_CD, nfit_uuid[NFIT_SPA_PCD]);
2965 	acpi_str_to_uuid(UUID_NFIT_BUS, nfit_uuid[NFIT_DEV_BUS]);
2966 	acpi_str_to_uuid(UUID_NFIT_DIMM, nfit_uuid[NFIT_DEV_DIMM]);
2967 	acpi_str_to_uuid(UUID_NFIT_DIMM_N_HPE1, nfit_uuid[NFIT_DEV_DIMM_N_HPE1]);
2968 	acpi_str_to_uuid(UUID_NFIT_DIMM_N_HPE2, nfit_uuid[NFIT_DEV_DIMM_N_HPE2]);
2969 	acpi_str_to_uuid(UUID_NFIT_DIMM_N_MSFT, nfit_uuid[NFIT_DEV_DIMM_N_MSFT]);
2970 
2971 	nfit_wq = create_singlethread_workqueue("nfit");
2972 	if (!nfit_wq)
2973 		return -ENOMEM;
2974 
2975 	nfit_mce_register();
2976 
2977 	return acpi_bus_register_driver(&acpi_nfit_driver);
2978 }
2979 
2980 static __exit void nfit_exit(void)
2981 {
2982 	nfit_mce_unregister();
2983 	acpi_bus_unregister_driver(&acpi_nfit_driver);
2984 	destroy_workqueue(nfit_wq);
2985 	WARN_ON(!list_empty(&acpi_descs));
2986 }
2987 
2988 module_init(nfit_init);
2989 module_exit(nfit_exit);
2990 MODULE_LICENSE("GPL v2");
2991 MODULE_AUTHOR("Intel Corporation");
2992