1/*
2 * APEI Error INJection support
3 *
4 * EINJ provides a hardware error injection mechanism, this is useful
5 * for debugging and testing of other APEI and RAS features.
6 *
7 * For more information about EINJ, please refer to ACPI Specification
8 * version 4.0, section 17.5.
9 *
10 * Copyright 2009-2010 Intel Corp.
11 *   Author: Huang Ying <ying.huang@intel.com>
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License version
15 * 2 as published by the Free Software Foundation.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
25 */
26
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/init.h>
30#include <linux/io.h>
31#include <linux/debugfs.h>
32#include <linux/seq_file.h>
33#include <linux/nmi.h>
34#include <linux/delay.h>
35#include <linux/mm.h>
36#include <asm/unaligned.h>
37
38#include "apei-internal.h"
39
40#define EINJ_PFX "EINJ: "
41
42#define SPIN_UNIT		100			/* 100ns */
43/* Firmware should respond within 1 milliseconds */
44#define FIRMWARE_TIMEOUT	(1 * NSEC_PER_MSEC)
45#define ACPI5_VENDOR_BIT	BIT(31)
46#define MEM_ERROR_MASK		(ACPI_EINJ_MEMORY_CORRECTABLE | \
47				ACPI_EINJ_MEMORY_UNCORRECTABLE | \
48				ACPI_EINJ_MEMORY_FATAL)
49
50/*
51 * ACPI version 5 provides a SET_ERROR_TYPE_WITH_ADDRESS action.
52 */
53static int acpi5;
54
55struct set_error_type_with_address {
56	u32	type;
57	u32	vendor_extension;
58	u32	flags;
59	u32	apicid;
60	u64	memory_address;
61	u64	memory_address_range;
62	u32	pcie_sbdf;
63};
64enum {
65	SETWA_FLAGS_APICID = 1,
66	SETWA_FLAGS_MEM = 2,
67	SETWA_FLAGS_PCIE_SBDF = 4,
68};
69
70/*
71 * Vendor extensions for platform specific operations
72 */
73struct vendor_error_type_extension {
74	u32	length;
75	u32	pcie_sbdf;
76	u16	vendor_id;
77	u16	device_id;
78	u8	rev_id;
79	u8	reserved[3];
80};
81
82static u32 notrigger;
83
84static u32 vendor_flags;
85static struct debugfs_blob_wrapper vendor_blob;
86static char vendor_dev[64];
87
88/*
89 * Some BIOSes allow parameters to the SET_ERROR_TYPE entries in the
90 * EINJ table through an unpublished extension. Use with caution as
91 * most will ignore the parameter and make their own choice of address
92 * for error injection.  This extension is used only if
93 * param_extension module parameter is specified.
94 */
95struct einj_parameter {
96	u64 type;
97	u64 reserved1;
98	u64 reserved2;
99	u64 param1;
100	u64 param2;
101};
102
103#define EINJ_OP_BUSY			0x1
104#define EINJ_STATUS_SUCCESS		0x0
105#define EINJ_STATUS_FAIL		0x1
106#define EINJ_STATUS_INVAL		0x2
107
108#define EINJ_TAB_ENTRY(tab)						\
109	((struct acpi_whea_header *)((char *)(tab) +			\
110				    sizeof(struct acpi_table_einj)))
111
112static bool param_extension;
113module_param(param_extension, bool, 0);
114
115static struct acpi_table_einj *einj_tab;
116
117static struct apei_resources einj_resources;
118
119static struct apei_exec_ins_type einj_ins_type[] = {
120	[ACPI_EINJ_READ_REGISTER] = {
121		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
122		.run   = apei_exec_read_register,
123	},
124	[ACPI_EINJ_READ_REGISTER_VALUE] = {
125		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
126		.run   = apei_exec_read_register_value,
127	},
128	[ACPI_EINJ_WRITE_REGISTER] = {
129		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
130		.run   = apei_exec_write_register,
131	},
132	[ACPI_EINJ_WRITE_REGISTER_VALUE] = {
133		.flags = APEI_EXEC_INS_ACCESS_REGISTER,
134		.run   = apei_exec_write_register_value,
135	},
136	[ACPI_EINJ_NOOP] = {
137		.flags = 0,
138		.run   = apei_exec_noop,
139	},
140};
141
142/*
143 * Prevent EINJ interpreter to run simultaneously, because the
144 * corresponding firmware implementation may not work properly when
145 * invoked simultaneously.
146 */
147static DEFINE_MUTEX(einj_mutex);
148
149static void *einj_param;
150
151static void einj_exec_ctx_init(struct apei_exec_context *ctx)
152{
153	apei_exec_ctx_init(ctx, einj_ins_type, ARRAY_SIZE(einj_ins_type),
154			   EINJ_TAB_ENTRY(einj_tab), einj_tab->entries);
155}
156
157static int __einj_get_available_error_type(u32 *type)
158{
159	struct apei_exec_context ctx;
160	int rc;
161
162	einj_exec_ctx_init(&ctx);
163	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_ERROR_TYPE);
164	if (rc)
165		return rc;
166	*type = apei_exec_ctx_get_output(&ctx);
167
168	return 0;
169}
170
171/* Get error injection capabilities of the platform */
172static int einj_get_available_error_type(u32 *type)
173{
174	int rc;
175
176	mutex_lock(&einj_mutex);
177	rc = __einj_get_available_error_type(type);
178	mutex_unlock(&einj_mutex);
179
180	return rc;
181}
182
183static int einj_timedout(u64 *t)
184{
185	if ((s64)*t < SPIN_UNIT) {
186		pr_warning(FW_WARN EINJ_PFX
187			   "Firmware does not respond in time\n");
188		return 1;
189	}
190	*t -= SPIN_UNIT;
191	ndelay(SPIN_UNIT);
192	touch_nmi_watchdog();
193	return 0;
194}
195
196static void check_vendor_extension(u64 paddr,
197				   struct set_error_type_with_address *v5param)
198{
199	int	offset = v5param->vendor_extension;
200	struct	vendor_error_type_extension *v;
201	u32	sbdf;
202
203	if (!offset)
204		return;
205	v = acpi_os_map_iomem(paddr + offset, sizeof(*v));
206	if (!v)
207		return;
208	sbdf = v->pcie_sbdf;
209	sprintf(vendor_dev, "%x:%x:%x.%x vendor_id=%x device_id=%x rev_id=%x\n",
210		sbdf >> 24, (sbdf >> 16) & 0xff,
211		(sbdf >> 11) & 0x1f, (sbdf >> 8) & 0x7,
212		 v->vendor_id, v->device_id, v->rev_id);
213	acpi_os_unmap_iomem(v, sizeof(*v));
214}
215
216static void *einj_get_parameter_address(void)
217{
218	int i;
219	u64 pa_v4 = 0, pa_v5 = 0;
220	struct acpi_whea_header *entry;
221
222	entry = EINJ_TAB_ENTRY(einj_tab);
223	for (i = 0; i < einj_tab->entries; i++) {
224		if (entry->action == ACPI_EINJ_SET_ERROR_TYPE &&
225		    entry->instruction == ACPI_EINJ_WRITE_REGISTER &&
226		    entry->register_region.space_id ==
227		    ACPI_ADR_SPACE_SYSTEM_MEMORY)
228			pa_v4 = get_unaligned(&entry->register_region.address);
229		if (entry->action == ACPI_EINJ_SET_ERROR_TYPE_WITH_ADDRESS &&
230		    entry->instruction == ACPI_EINJ_WRITE_REGISTER &&
231		    entry->register_region.space_id ==
232		    ACPI_ADR_SPACE_SYSTEM_MEMORY)
233			pa_v5 = get_unaligned(&entry->register_region.address);
234		entry++;
235	}
236	if (pa_v5) {
237		struct set_error_type_with_address *v5param;
238
239		v5param = acpi_os_map_iomem(pa_v5, sizeof(*v5param));
240		if (v5param) {
241			acpi5 = 1;
242			check_vendor_extension(pa_v5, v5param);
243			return v5param;
244		}
245	}
246	if (param_extension && pa_v4) {
247		struct einj_parameter *v4param;
248
249		v4param = acpi_os_map_iomem(pa_v4, sizeof(*v4param));
250		if (!v4param)
251			return NULL;
252		if (v4param->reserved1 || v4param->reserved2) {
253			acpi_os_unmap_iomem(v4param, sizeof(*v4param));
254			return NULL;
255		}
256		return v4param;
257	}
258
259	return NULL;
260}
261
262/* do sanity check to trigger table */
263static int einj_check_trigger_header(struct acpi_einj_trigger *trigger_tab)
264{
265	if (trigger_tab->header_size != sizeof(struct acpi_einj_trigger))
266		return -EINVAL;
267	if (trigger_tab->table_size > PAGE_SIZE ||
268	    trigger_tab->table_size < trigger_tab->header_size)
269		return -EINVAL;
270	if (trigger_tab->entry_count !=
271	    (trigger_tab->table_size - trigger_tab->header_size) /
272	    sizeof(struct acpi_einj_entry))
273		return -EINVAL;
274
275	return 0;
276}
277
278static struct acpi_generic_address *einj_get_trigger_parameter_region(
279	struct acpi_einj_trigger *trigger_tab, u64 param1, u64 param2)
280{
281	int i;
282	struct acpi_whea_header *entry;
283
284	entry = (struct acpi_whea_header *)
285		((char *)trigger_tab + sizeof(struct acpi_einj_trigger));
286	for (i = 0; i < trigger_tab->entry_count; i++) {
287		if (entry->action == ACPI_EINJ_TRIGGER_ERROR &&
288		entry->instruction == ACPI_EINJ_WRITE_REGISTER_VALUE &&
289		entry->register_region.space_id ==
290			ACPI_ADR_SPACE_SYSTEM_MEMORY &&
291		(entry->register_region.address & param2) == (param1 & param2))
292			return &entry->register_region;
293		entry++;
294	}
295
296	return NULL;
297}
298/* Execute instructions in trigger error action table */
299static int __einj_error_trigger(u64 trigger_paddr, u32 type,
300				u64 param1, u64 param2)
301{
302	struct acpi_einj_trigger *trigger_tab = NULL;
303	struct apei_exec_context trigger_ctx;
304	struct apei_resources trigger_resources;
305	struct acpi_whea_header *trigger_entry;
306	struct resource *r;
307	u32 table_size;
308	int rc = -EIO;
309	struct acpi_generic_address *trigger_param_region = NULL;
310
311	r = request_mem_region(trigger_paddr, sizeof(*trigger_tab),
312			       "APEI EINJ Trigger Table");
313	if (!r) {
314		pr_err(EINJ_PFX
315	"Can not request [mem %#010llx-%#010llx] for Trigger table\n",
316		       (unsigned long long)trigger_paddr,
317		       (unsigned long long)trigger_paddr +
318			    sizeof(*trigger_tab) - 1);
319		goto out;
320	}
321	trigger_tab = ioremap_cache(trigger_paddr, sizeof(*trigger_tab));
322	if (!trigger_tab) {
323		pr_err(EINJ_PFX "Failed to map trigger table!\n");
324		goto out_rel_header;
325	}
326	rc = einj_check_trigger_header(trigger_tab);
327	if (rc) {
328		pr_warning(FW_BUG EINJ_PFX
329			   "The trigger error action table is invalid\n");
330		goto out_rel_header;
331	}
332
333	/* No action structures in the TRIGGER_ERROR table, nothing to do */
334	if (!trigger_tab->entry_count)
335		goto out_rel_header;
336
337	rc = -EIO;
338	table_size = trigger_tab->table_size;
339	r = request_mem_region(trigger_paddr + sizeof(*trigger_tab),
340			       table_size - sizeof(*trigger_tab),
341			       "APEI EINJ Trigger Table");
342	if (!r) {
343		pr_err(EINJ_PFX
344"Can not request [mem %#010llx-%#010llx] for Trigger Table Entry\n",
345		       (unsigned long long)trigger_paddr + sizeof(*trigger_tab),
346		       (unsigned long long)trigger_paddr + table_size - 1);
347		goto out_rel_header;
348	}
349	iounmap(trigger_tab);
350	trigger_tab = ioremap_cache(trigger_paddr, table_size);
351	if (!trigger_tab) {
352		pr_err(EINJ_PFX "Failed to map trigger table!\n");
353		goto out_rel_entry;
354	}
355	trigger_entry = (struct acpi_whea_header *)
356		((char *)trigger_tab + sizeof(struct acpi_einj_trigger));
357	apei_resources_init(&trigger_resources);
358	apei_exec_ctx_init(&trigger_ctx, einj_ins_type,
359			   ARRAY_SIZE(einj_ins_type),
360			   trigger_entry, trigger_tab->entry_count);
361	rc = apei_exec_collect_resources(&trigger_ctx, &trigger_resources);
362	if (rc)
363		goto out_fini;
364	rc = apei_resources_sub(&trigger_resources, &einj_resources);
365	if (rc)
366		goto out_fini;
367	/*
368	 * Some firmware will access target address specified in
369	 * param1 to trigger the error when injecting memory error.
370	 * This will cause resource conflict with regular memory.  So
371	 * remove it from trigger table resources.
372	 */
373	if ((param_extension || acpi5) && (type & MEM_ERROR_MASK) && param2) {
374		struct apei_resources addr_resources;
375		apei_resources_init(&addr_resources);
376		trigger_param_region = einj_get_trigger_parameter_region(
377			trigger_tab, param1, param2);
378		if (trigger_param_region) {
379			rc = apei_resources_add(&addr_resources,
380				trigger_param_region->address,
381				trigger_param_region->bit_width/8, true);
382			if (rc)
383				goto out_fini;
384			rc = apei_resources_sub(&trigger_resources,
385					&addr_resources);
386		}
387		apei_resources_fini(&addr_resources);
388		if (rc)
389			goto out_fini;
390	}
391	rc = apei_resources_request(&trigger_resources, "APEI EINJ Trigger");
392	if (rc)
393		goto out_fini;
394	rc = apei_exec_pre_map_gars(&trigger_ctx);
395	if (rc)
396		goto out_release;
397
398	rc = apei_exec_run(&trigger_ctx, ACPI_EINJ_TRIGGER_ERROR);
399
400	apei_exec_post_unmap_gars(&trigger_ctx);
401out_release:
402	apei_resources_release(&trigger_resources);
403out_fini:
404	apei_resources_fini(&trigger_resources);
405out_rel_entry:
406	release_mem_region(trigger_paddr + sizeof(*trigger_tab),
407			   table_size - sizeof(*trigger_tab));
408out_rel_header:
409	release_mem_region(trigger_paddr, sizeof(*trigger_tab));
410out:
411	if (trigger_tab)
412		iounmap(trigger_tab);
413
414	return rc;
415}
416
417static int __einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
418			       u64 param3, u64 param4)
419{
420	struct apei_exec_context ctx;
421	u64 val, trigger_paddr, timeout = FIRMWARE_TIMEOUT;
422	int rc;
423
424	einj_exec_ctx_init(&ctx);
425
426	rc = apei_exec_run_optional(&ctx, ACPI_EINJ_BEGIN_OPERATION);
427	if (rc)
428		return rc;
429	apei_exec_ctx_set_input(&ctx, type);
430	if (acpi5) {
431		struct set_error_type_with_address *v5param = einj_param;
432
433		v5param->type = type;
434		if (type & ACPI5_VENDOR_BIT) {
435			switch (vendor_flags) {
436			case SETWA_FLAGS_APICID:
437				v5param->apicid = param1;
438				break;
439			case SETWA_FLAGS_MEM:
440				v5param->memory_address = param1;
441				v5param->memory_address_range = param2;
442				break;
443			case SETWA_FLAGS_PCIE_SBDF:
444				v5param->pcie_sbdf = param1;
445				break;
446			}
447			v5param->flags = vendor_flags;
448		} else if (flags) {
449				v5param->flags = flags;
450				v5param->memory_address = param1;
451				v5param->memory_address_range = param2;
452				v5param->apicid = param3;
453				v5param->pcie_sbdf = param4;
454		} else {
455			switch (type) {
456			case ACPI_EINJ_PROCESSOR_CORRECTABLE:
457			case ACPI_EINJ_PROCESSOR_UNCORRECTABLE:
458			case ACPI_EINJ_PROCESSOR_FATAL:
459				v5param->apicid = param1;
460				v5param->flags = SETWA_FLAGS_APICID;
461				break;
462			case ACPI_EINJ_MEMORY_CORRECTABLE:
463			case ACPI_EINJ_MEMORY_UNCORRECTABLE:
464			case ACPI_EINJ_MEMORY_FATAL:
465				v5param->memory_address = param1;
466				v5param->memory_address_range = param2;
467				v5param->flags = SETWA_FLAGS_MEM;
468				break;
469			case ACPI_EINJ_PCIX_CORRECTABLE:
470			case ACPI_EINJ_PCIX_UNCORRECTABLE:
471			case ACPI_EINJ_PCIX_FATAL:
472				v5param->pcie_sbdf = param1;
473				v5param->flags = SETWA_FLAGS_PCIE_SBDF;
474				break;
475			}
476		}
477	} else {
478		rc = apei_exec_run(&ctx, ACPI_EINJ_SET_ERROR_TYPE);
479		if (rc)
480			return rc;
481		if (einj_param) {
482			struct einj_parameter *v4param = einj_param;
483			v4param->param1 = param1;
484			v4param->param2 = param2;
485		}
486	}
487	rc = apei_exec_run(&ctx, ACPI_EINJ_EXECUTE_OPERATION);
488	if (rc)
489		return rc;
490	for (;;) {
491		rc = apei_exec_run(&ctx, ACPI_EINJ_CHECK_BUSY_STATUS);
492		if (rc)
493			return rc;
494		val = apei_exec_ctx_get_output(&ctx);
495		if (!(val & EINJ_OP_BUSY))
496			break;
497		if (einj_timedout(&timeout))
498			return -EIO;
499	}
500	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_COMMAND_STATUS);
501	if (rc)
502		return rc;
503	val = apei_exec_ctx_get_output(&ctx);
504	if (val != EINJ_STATUS_SUCCESS)
505		return -EBUSY;
506
507	rc = apei_exec_run(&ctx, ACPI_EINJ_GET_TRIGGER_TABLE);
508	if (rc)
509		return rc;
510	trigger_paddr = apei_exec_ctx_get_output(&ctx);
511	if (notrigger == 0) {
512		rc = __einj_error_trigger(trigger_paddr, type, param1, param2);
513		if (rc)
514			return rc;
515	}
516	rc = apei_exec_run_optional(&ctx, ACPI_EINJ_END_OPERATION);
517
518	return rc;
519}
520
521/* Inject the specified hardware error */
522static int einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
523			     u64 param3, u64 param4)
524{
525	int rc;
526	unsigned long pfn;
527
528	/* If user manually set "flags", make sure it is legal */
529	if (flags && (flags &
530		~(SETWA_FLAGS_APICID|SETWA_FLAGS_MEM|SETWA_FLAGS_PCIE_SBDF)))
531		return -EINVAL;
532
533	/*
534	 * We need extra sanity checks for memory errors.
535	 * Other types leap directly to injection.
536	 */
537
538	/* ensure param1/param2 existed */
539	if (!(param_extension || acpi5))
540		goto inject;
541
542	/* ensure injection is memory related */
543	if (type & ACPI5_VENDOR_BIT) {
544		if (vendor_flags != SETWA_FLAGS_MEM)
545			goto inject;
546	} else if (!(type & MEM_ERROR_MASK) && !(flags & SETWA_FLAGS_MEM))
547		goto inject;
548
549	/*
550	 * Disallow crazy address masks that give BIOS leeway to pick
551	 * injection address almost anywhere. Insist on page or
552	 * better granularity and that target address is normal RAM.
553	 */
554	pfn = PFN_DOWN(param1 & param2);
555	if (!page_is_ram(pfn) || ((param2 & PAGE_MASK) != PAGE_MASK))
556		return -EINVAL;
557
558inject:
559	mutex_lock(&einj_mutex);
560	rc = __einj_error_inject(type, flags, param1, param2, param3, param4);
561	mutex_unlock(&einj_mutex);
562
563	return rc;
564}
565
566static u32 error_type;
567static u32 error_flags;
568static u64 error_param1;
569static u64 error_param2;
570static u64 error_param3;
571static u64 error_param4;
572static struct dentry *einj_debug_dir;
573
574static int available_error_type_show(struct seq_file *m, void *v)
575{
576	int rc;
577	u32 available_error_type = 0;
578
579	rc = einj_get_available_error_type(&available_error_type);
580	if (rc)
581		return rc;
582	if (available_error_type & 0x0001)
583		seq_printf(m, "0x00000001\tProcessor Correctable\n");
584	if (available_error_type & 0x0002)
585		seq_printf(m, "0x00000002\tProcessor Uncorrectable non-fatal\n");
586	if (available_error_type & 0x0004)
587		seq_printf(m, "0x00000004\tProcessor Uncorrectable fatal\n");
588	if (available_error_type & 0x0008)
589		seq_printf(m, "0x00000008\tMemory Correctable\n");
590	if (available_error_type & 0x0010)
591		seq_printf(m, "0x00000010\tMemory Uncorrectable non-fatal\n");
592	if (available_error_type & 0x0020)
593		seq_printf(m, "0x00000020\tMemory Uncorrectable fatal\n");
594	if (available_error_type & 0x0040)
595		seq_printf(m, "0x00000040\tPCI Express Correctable\n");
596	if (available_error_type & 0x0080)
597		seq_printf(m, "0x00000080\tPCI Express Uncorrectable non-fatal\n");
598	if (available_error_type & 0x0100)
599		seq_printf(m, "0x00000100\tPCI Express Uncorrectable fatal\n");
600	if (available_error_type & 0x0200)
601		seq_printf(m, "0x00000200\tPlatform Correctable\n");
602	if (available_error_type & 0x0400)
603		seq_printf(m, "0x00000400\tPlatform Uncorrectable non-fatal\n");
604	if (available_error_type & 0x0800)
605		seq_printf(m, "0x00000800\tPlatform Uncorrectable fatal\n");
606
607	return 0;
608}
609
610static int available_error_type_open(struct inode *inode, struct file *file)
611{
612	return single_open(file, available_error_type_show, NULL);
613}
614
615static const struct file_operations available_error_type_fops = {
616	.open		= available_error_type_open,
617	.read		= seq_read,
618	.llseek		= seq_lseek,
619	.release	= single_release,
620};
621
622static int error_type_get(void *data, u64 *val)
623{
624	*val = error_type;
625
626	return 0;
627}
628
629static int error_type_set(void *data, u64 val)
630{
631	int rc;
632	u32 available_error_type = 0;
633	u32 tval, vendor;
634
635	/*
636	 * Vendor defined types have 0x80000000 bit set, and
637	 * are not enumerated by ACPI_EINJ_GET_ERROR_TYPE
638	 */
639	vendor = val & ACPI5_VENDOR_BIT;
640	tval = val & 0x7fffffff;
641
642	/* Only one error type can be specified */
643	if (tval & (tval - 1))
644		return -EINVAL;
645	if (!vendor) {
646		rc = einj_get_available_error_type(&available_error_type);
647		if (rc)
648			return rc;
649		if (!(val & available_error_type))
650			return -EINVAL;
651	}
652	error_type = val;
653
654	return 0;
655}
656
657DEFINE_SIMPLE_ATTRIBUTE(error_type_fops, error_type_get,
658			error_type_set, "0x%llx\n");
659
660static int error_inject_set(void *data, u64 val)
661{
662	if (!error_type)
663		return -EINVAL;
664
665	return einj_error_inject(error_type, error_flags, error_param1, error_param2,
666		error_param3, error_param4);
667}
668
669DEFINE_SIMPLE_ATTRIBUTE(error_inject_fops, NULL,
670			error_inject_set, "%llu\n");
671
672static int einj_check_table(struct acpi_table_einj *einj_tab)
673{
674	if ((einj_tab->header_length !=
675	     (sizeof(struct acpi_table_einj) - sizeof(einj_tab->header)))
676	    && (einj_tab->header_length != sizeof(struct acpi_table_einj)))
677		return -EINVAL;
678	if (einj_tab->header.length < sizeof(struct acpi_table_einj))
679		return -EINVAL;
680	if (einj_tab->entries !=
681	    (einj_tab->header.length - sizeof(struct acpi_table_einj)) /
682	    sizeof(struct acpi_einj_entry))
683		return -EINVAL;
684
685	return 0;
686}
687
688static int __init einj_init(void)
689{
690	int rc;
691	acpi_status status;
692	struct dentry *fentry;
693	struct apei_exec_context ctx;
694
695	if (acpi_disabled)
696		return -ENODEV;
697
698	status = acpi_get_table(ACPI_SIG_EINJ, 0,
699				(struct acpi_table_header **)&einj_tab);
700	if (status == AE_NOT_FOUND)
701		return -ENODEV;
702	else if (ACPI_FAILURE(status)) {
703		const char *msg = acpi_format_exception(status);
704		pr_err(EINJ_PFX "Failed to get table, %s\n", msg);
705		return -EINVAL;
706	}
707
708	rc = einj_check_table(einj_tab);
709	if (rc) {
710		pr_warning(FW_BUG EINJ_PFX "EINJ table is invalid\n");
711		return -EINVAL;
712	}
713
714	rc = -ENOMEM;
715	einj_debug_dir = debugfs_create_dir("einj", apei_get_debugfs_dir());
716	if (!einj_debug_dir)
717		goto err_cleanup;
718	fentry = debugfs_create_file("available_error_type", S_IRUSR,
719				     einj_debug_dir, NULL,
720				     &available_error_type_fops);
721	if (!fentry)
722		goto err_cleanup;
723	fentry = debugfs_create_file("error_type", S_IRUSR | S_IWUSR,
724				     einj_debug_dir, NULL, &error_type_fops);
725	if (!fentry)
726		goto err_cleanup;
727	fentry = debugfs_create_file("error_inject", S_IWUSR,
728				     einj_debug_dir, NULL, &error_inject_fops);
729	if (!fentry)
730		goto err_cleanup;
731
732	apei_resources_init(&einj_resources);
733	einj_exec_ctx_init(&ctx);
734	rc = apei_exec_collect_resources(&ctx, &einj_resources);
735	if (rc)
736		goto err_fini;
737	rc = apei_resources_request(&einj_resources, "APEI EINJ");
738	if (rc)
739		goto err_fini;
740	rc = apei_exec_pre_map_gars(&ctx);
741	if (rc)
742		goto err_release;
743
744	rc = -ENOMEM;
745	einj_param = einj_get_parameter_address();
746	if ((param_extension || acpi5) && einj_param) {
747		fentry = debugfs_create_x32("flags", S_IRUSR | S_IWUSR,
748					    einj_debug_dir, &error_flags);
749		if (!fentry)
750			goto err_unmap;
751		fentry = debugfs_create_x64("param1", S_IRUSR | S_IWUSR,
752					    einj_debug_dir, &error_param1);
753		if (!fentry)
754			goto err_unmap;
755		fentry = debugfs_create_x64("param2", S_IRUSR | S_IWUSR,
756					    einj_debug_dir, &error_param2);
757		if (!fentry)
758			goto err_unmap;
759		fentry = debugfs_create_x64("param3", S_IRUSR | S_IWUSR,
760					    einj_debug_dir, &error_param3);
761		if (!fentry)
762			goto err_unmap;
763		fentry = debugfs_create_x64("param4", S_IRUSR | S_IWUSR,
764					    einj_debug_dir, &error_param4);
765		if (!fentry)
766			goto err_unmap;
767
768		fentry = debugfs_create_x32("notrigger", S_IRUSR | S_IWUSR,
769					    einj_debug_dir, &notrigger);
770		if (!fentry)
771			goto err_unmap;
772	}
773
774	if (vendor_dev[0]) {
775		vendor_blob.data = vendor_dev;
776		vendor_blob.size = strlen(vendor_dev);
777		fentry = debugfs_create_blob("vendor", S_IRUSR,
778					     einj_debug_dir, &vendor_blob);
779		if (!fentry)
780			goto err_unmap;
781		fentry = debugfs_create_x32("vendor_flags", S_IRUSR | S_IWUSR,
782					    einj_debug_dir, &vendor_flags);
783		if (!fentry)
784			goto err_unmap;
785	}
786
787	pr_info(EINJ_PFX "Error INJection is initialized.\n");
788
789	return 0;
790
791err_unmap:
792	if (einj_param) {
793		acpi_size size = (acpi5) ?
794			sizeof(struct set_error_type_with_address) :
795			sizeof(struct einj_parameter);
796
797		acpi_os_unmap_iomem(einj_param, size);
798	}
799	apei_exec_post_unmap_gars(&ctx);
800err_release:
801	apei_resources_release(&einj_resources);
802err_fini:
803	apei_resources_fini(&einj_resources);
804err_cleanup:
805	debugfs_remove_recursive(einj_debug_dir);
806
807	return rc;
808}
809
810static void __exit einj_exit(void)
811{
812	struct apei_exec_context ctx;
813
814	if (einj_param) {
815		acpi_size size = (acpi5) ?
816			sizeof(struct set_error_type_with_address) :
817			sizeof(struct einj_parameter);
818
819		acpi_os_unmap_iomem(einj_param, size);
820	}
821	einj_exec_ctx_init(&ctx);
822	apei_exec_post_unmap_gars(&ctx);
823	apei_resources_release(&einj_resources);
824	apei_resources_fini(&einj_resources);
825	debugfs_remove_recursive(einj_debug_dir);
826}
827
828module_init(einj_init);
829module_exit(einj_exit);
830
831MODULE_AUTHOR("Huang Ying");
832MODULE_DESCRIPTION("APEI Error INJection support");
833MODULE_LICENSE("GPL");
834