aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pci/pcie/aer/aer_inject.c
blob: 4e24cb8a94aec0ecee6e0e923f5ffee50439e601 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
/*
 * PCIe AER software error injection support.
 *
 * Debuging PCIe AER code is quite difficult because it is hard to
 * trigger various real hardware errors. Software based error
 * injection can fake almost all kinds of errors with the help of a
 * user space helper tool aer-inject, which can be gotten from:
 *   http://www.kernel.org/pub/linux/utils/pci/aer-inject/
 *
 * Copyright 2009 Intel Corporation.
 *     Huang Ying <ying.huang@intel.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; version 2
 * of the License.
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/stddef.h>
#include "aerdrv.h"

/* Override the existing corrected and uncorrected error masks */
static bool aer_mask_override;
module_param(aer_mask_override, bool, 0);

struct aer_error_inj {
	u8 bus;
	u8 dev;
	u8 fn;
	u32 uncor_status;
	u32 cor_status;
	u32 header_log0;
	u32 header_log1;
	u32 header_log2;
	u32 header_log3;
	u16 domain;
};

struct aer_error {
	struct list_head list;
	u16 domain;
	unsigned int bus;
	unsigned int devfn;
	int pos_cap_err;

	u32 uncor_status;
	u32 cor_status;
	u32 header_log0;
	u32 header_log1;
	u32 header_log2;
	u32 header_log3;
	u32 root_status;
	u32 source_id;
};

struct pci_bus_ops {
	struct list_head list;
	struct pci_bus *bus;
	struct pci_ops *ops;
};

static LIST_HEAD(einjected);

static LIST_HEAD(pci_bus_ops_list);

/* Protect einjected and pci_bus_ops_list */
static DEFINE_SPINLOCK(inject_lock);

static void aer_error_init(struct aer_error *err, u16 domain,
			   unsigned int bus, unsigned int devfn,
			   int pos_cap_err)
{
	INIT_LIST_HEAD(&err->list);
	err->domain = domain;
	err->bus = bus;
	err->devfn = devfn;
	err->pos_cap_err = pos_cap_err;
}

/* inject_lock must be held before calling */
static struct aer_error *__find_aer_error(u16 domain, unsigned int bus,
					  unsigned int devfn)
{
	struct aer_error *err;

	list_for_each_entry(err, &einjected, list) {
		if (domain == err->domain &&
		    bus == err->bus &&
		    devfn == err->devfn)
			return err;
	}
	return NULL;
}

/* inject_lock must be held before calling */
static struct aer_error *__find_aer_error_by_dev(struct pci_dev *dev)
{
	int domain = pci_domain_nr(dev->bus);
	if (domain < 0)
		return NULL;
	return __find_aer_error((u16)domain, dev->bus->number, dev->devfn);
}

/* inject_lock must be held before calling */
static struct pci_ops *__find_pci_bus_ops(struct pci_bus *bus)
{
	struct pci_bus_ops *bus_ops;

	list_for_each_entry(bus_ops, &pci_bus_ops_list, list) {
		if (bus_ops->bus == bus)
			return bus_ops->ops;
	}
	return NULL;
}

static struct pci_bus_ops *pci_bus_ops_pop(void)
{
	unsigned long flags;
	struct pci_bus_ops *bus_ops = NULL;

	spin_lock_irqsave(&inject_lock, flags);
	if (list_empty(&pci_bus_ops_list))
		bus_ops = NULL;
	else {
		struct list_head *lh = pci_bus_ops_list.next;
		list_del(lh);
		bus_ops = list_entry(lh, struct pci_bus_ops, list);
	}
	spin_unlock_irqrestore(&inject_lock, flags);
	return bus_ops;
}

static u32 *find_pci_config_dword(struct aer_error *err, int where,
				  int *prw1cs)
{
	int rw1cs = 0;
	u32 *target = NULL;

	if (err->pos_cap_err == -1)
		return NULL;

	switch (where - err->pos_cap_err) {
	case PCI_ERR_UNCOR_STATUS:
		target = &err->uncor_status;
		rw1cs = 1;
		break;
	case PCI_ERR_COR_STATUS:
		target = &err->cor_status;
		rw1cs = 1;
		break;
	case PCI_ERR_HEADER_LOG:
		target = &err->header_log0;
		break;
	case PCI_ERR_HEADER_LOG+4:
		target = &err->header_log1;
		break;
	case PCI_ERR_HEADER_LOG+8:
		target = &err->header_log2;
		break;
	case PCI_ERR_HEADER_LOG+12:
		target = &err->header_log3;
		break;
	case PCI_ERR_ROOT_STATUS:
		target = &err->root_status;
		rw1cs = 1;
		break;
	case PCI_ERR_ROOT_ERR_SRC:
		target = &err->source_id;
		break;
	}
	if (prw1cs)
		*prw1cs = rw1cs;
	return target;
}

static int pci_read_aer(struct pci_bus *bus, unsigned int devfn, int where,
			int size, u32 *val)
{
	u32 *sim;
	struct aer_error *err;
	unsigned long flags;
	struct pci_ops *ops;
	int domain;

	spin_lock_irqsave(&inject_lock, flags);
	if (size != sizeof(u32))
		goto out;
	domain = pci_domain_nr(bus);
	if (domain < 0)
		goto out;
	err = __find_aer_error((u16)domain, bus->number, devfn);
	if (!err)
		goto out;

	sim = find_pci_config_dword(err, where, NULL);
	if (sim) {
		*val = *sim;
		spin_unlock_irqrestore(&inject_lock, flags);
		return 0;
	}
out:
	ops = __find_pci_bus_ops(bus);
	spin_unlock_irqrestore(&inject_lock, flags);
	return ops->read(bus, devfn, where, size, val);
}

int pci_write_aer(struct pci_bus *bus, unsigned int devfn, int where, int size,
		  u32 val)
{
	u32 *sim;
	struct aer_error *err;
	unsigned long flags;
	int rw1cs;
	struct pci_ops *ops;
	int domain;

	spin_lock_irqsave(&inject_lock, flags);
	if (size != sizeof(u32))
		goto out;
	domain = pci_domain_nr(bus);
	if (domain < 0)
		goto out;
	err = __find_aer_error((u16)domain, bus->number, devfn);
	if (!err)
		goto out;

	sim = find_pci_config_dword(err, where, &rw1cs);
	if (sim) {
		if (rw1cs)
			*sim ^= val;
		else
			*sim = val;
		spin_unlock_irqrestore(&inject_lock, flags);
		return 0;
	}
out:
	ops = __find_pci_bus_ops(bus);
	spin_unlock_irqrestore(&inject_lock, flags);
	return ops->write(bus, devfn, where, size, val);
}

static struct pci_ops pci_ops_aer = {
	.read = pci_read_aer,
	.write = pci_write_aer,
};

static void pci_bus_ops_init(struct pci_bus_ops *bus_ops,
			     struct pci_bus *bus,
			     struct pci_ops *ops)
{
	INIT_LIST_HEAD(&bus_ops->list);
	bus_ops->bus = bus;
	bus_ops->ops = ops;
}

static int pci_bus_set_aer_ops(struct pci_bus *bus)
{
	struct pci_ops *ops;
	struct pci_bus_ops *bus_ops;
	unsigned long flags;

	bus_ops = kmalloc(sizeof(*bus_ops), GFP_KERNEL);
	if (!bus_ops)
		return -ENOMEM;
	ops = pci_bus_set_ops(bus, &pci_ops_aer);
	spin_lock_irqsave(&inject_lock, flags);
	if (ops == &pci_ops_aer)
		goto out;
	pci_bus_ops_init(bus_ops, bus, ops);
	list_add(&bus_ops->list, &pci_bus_ops_list);
	bus_ops = NULL;
out:
	spin_unlock_irqrestore(&inject_lock, flags);
	kfree(bus_ops);
	return 0;
}

static struct pci_dev *pcie_find_root_port(struct pci_dev *dev)
{
	while (1) {
		if (!pci_is_pcie(dev))
			break;
		if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT)
			return dev;
		if (!dev->bus->self)
			break;
		dev = dev->bus->self;
	}
	return NULL;
}

static int find_aer_device_iter(struct device *device, void *data)
{
	struct pcie_device **result = data;
	struct pcie_device *pcie_dev;

	if (device->bus == &pcie_port_bus_type) {
		pcie_dev = to_pcie_device(device);
		if (pcie_dev->service & PCIE_PORT_SERVICE_AER) {
			*result = pcie_dev;
			return 1;
		}
	}
	return 0;
}

static int find_aer_device(struct pci_dev *dev, struct pcie_device **result)
{
	return device_for_each_child(&dev->dev, result, find_aer_device_iter);
}

static int aer_inject(struct aer_error_inj *einj)
{
	struct aer_error *err, *rperr;
	struct aer_error *err_alloc = NULL, *rperr_alloc = NULL;
	struct pci_dev *dev, *rpdev;
	struct pcie_device *edev;
	unsigned long flags;
	unsigned int devfn = PCI_DEVFN(einj->dev, einj->fn);
	int pos_cap_err, rp_pos_cap_err;
	u32 sever, cor_mask, uncor_mask, cor_mask_orig = 0, uncor_mask_orig = 0;
	int ret = 0;

	dev = pci_get_domain_bus_and_slot((int)einj->domain, einj->bus, devfn);
	if (!dev)
		return -ENODEV;
	rpdev = pcie_find_root_port(dev);
	if (!rpdev) {
		ret = -ENOTTY;
		goto out_put;
	}

	pos_cap_err = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
	if (!pos_cap_err) {
		ret = -ENOTTY;
		goto out_put;
	}
	pci_read_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_SEVER, &sever);
	pci_read_config_dword(dev, pos_cap_err + PCI_ERR_COR_MASK, &cor_mask);
	pci_read_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_MASK,
			      &uncor_mask);

	rp_pos_cap_err = pci_find_ext_capability(rpdev, PCI_EXT_CAP_ID_ERR);
	if (!rp_pos_cap_err) {
		ret = -ENOTTY;
		goto out_put;
	}

	err_alloc =  kzalloc(sizeof(struct aer_error), GFP_KERNEL);
	if (!err_alloc) {
		ret = -ENOMEM;
		goto out_put;
	}
	rperr_alloc =  kzalloc(sizeof(struct aer_error), GFP_KERNEL);
	if (!rperr_alloc) {
		ret = -ENOMEM;
		goto out_put;
	}

	if (aer_mask_override) {
		cor_mask_orig = cor_mask;
		cor_mask &= !(einj->cor_status);
		pci_write_config_dword(dev, pos_cap_err + PCI_ERR_COR_MASK,
				       cor_mask);

		uncor_mask_orig = uncor_mask;
		uncor_mask &= !(einj->uncor_status);
		pci_write_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_MASK,
				       uncor_mask);
	}

	spin_lock_irqsave(&inject_lock, flags);

	err = __find_aer_error_by_dev(dev);
	if (!err) {
		err = err_alloc;
		err_alloc = NULL;
		aer_error_init(err, einj->domain, einj->bus, devfn,
			       pos_cap_err);
		list_add(&err->list, &einjected);
	}
	err->uncor_status |= einj->uncor_status;
	err->cor_status |= einj->cor_status;
	err->header_log0 = einj->header_log0;
	err->header_log1 = einj->header_log1;
	err->header_log2 = einj->header_log2;
	err->header_log3 = einj->header_log3;

	if (!aer_mask_override && einj->cor_status &&
	    !(einj->cor_status & ~cor_mask)) {
		ret = -EINVAL;
		printk(KERN_WARNING "The correctable error(s) is masked "
				"by device\n");
		spin_unlock_irqrestore(&inject_lock, flags);
		goto out_put;
	}
	if (!aer_mask_override && einj->uncor_status &&
	    !(einj->uncor_status & ~uncor_mask)) {
		ret = -EINVAL;
		printk(KERN_WARNING "The uncorrectable error(s) is masked "
				"by device\n");
		spin_unlock_irqrestore(&inject_lock, flags);
		goto out_put;
	}

	rperr = __find_aer_error_by_dev(rpdev);
	if (!rperr) {
		rperr = rperr_alloc;
		rperr_alloc = NULL;
		aer_error_init(rperr, pci_domain_nr(rpdev->bus),
			       rpdev->bus->number, rpdev->devfn,
			       rp_pos_cap_err);
		list_add(&rperr->list, &einjected);
	}
	if (einj->cor_status) {
		if (rperr->root_status & PCI_ERR_ROOT_COR_RCV)
			rperr->root_status |= PCI_ERR_ROOT_MULTI_COR_RCV;
		else
			rperr->root_status |= PCI_ERR_ROOT_COR_RCV;
		rperr->source_id &= 0xffff0000;
		rperr->source_id |= (einj->bus << 8) | devfn;
	}
	if (einj->uncor_status) {
		if (rperr->root_status & PCI_ERR_ROOT_UNCOR_RCV)
			rperr->root_status |= PCI_ERR_ROOT_MULTI_UNCOR_RCV;
		if (sever & einj->uncor_status) {
			rperr->root_status |= PCI_ERR_ROOT_FATAL_RCV;
			if (!(rperr->root_status & PCI_ERR_ROOT_UNCOR_RCV))
				rperr->root_status |= PCI_ERR_ROOT_FIRST_FATAL;
		} else
			rperr->root_status |= PCI_ERR_ROOT_NONFATAL_RCV;
		rperr->root_status |= PCI_ERR_ROOT_UNCOR_RCV;
		rperr->source_id &= 0x0000ffff;
		rperr->source_id |= ((einj->bus << 8) | devfn) << 16;
	}
	spin_unlock_irqrestore(&inject_lock, flags);

	if (aer_mask_override) {
		pci_write_config_dword(dev, pos_cap_err + PCI_ERR_COR_MASK,
				       cor_mask_orig);
		pci_write_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_MASK,
				       uncor_mask_orig);
	}

	ret = pci_bus_set_aer_ops(dev->bus);
	if (ret)
		goto out_put;
	ret = pci_bus_set_aer_ops(rpdev->bus);
	if (ret)
		goto out_put;

	if (find_aer_device(rpdev, &edev)) {
		if (!get_service_data(edev)) {
			printk(KERN_WARNING "AER service is not initialized\n");
			ret = -EINVAL;
			goto out_put;
		}
		aer_irq(-1, edev);
	}
	else
		ret = -EINVAL;
out_put:
	kfree(err_alloc);
	kfree(rperr_alloc);
	pci_dev_put(dev);
	return ret;
}

static ssize_t aer_inject_write(struct file *filp, const char __user *ubuf,
				size_t usize, loff_t *off)
{
	struct aer_error_inj einj;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;
	if (usize < offsetof(struct aer_error_inj, domain) ||
	    usize > sizeof(einj))
		return -EINVAL;

	memset(&einj, 0, sizeof(einj));
	if (copy_from_user(&einj, ubuf, usize))
		return -EFAULT;

	ret = aer_inject(&einj);
	return ret ? ret : usize;
}

static const struct file_operations aer_inject_fops = {
	.write = aer_inject_write,
	.owner = THIS_MODULE,
	.llseek = noop_llseek,
};

static struct miscdevice aer_inject_device = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "aer_inject",
	.fops = &aer_inject_fops,
};

static int __init aer_inject_init(void)
{
	return misc_register(&aer_inject_device);
}

static void __exit aer_inject_exit(void)
{
	struct aer_error *err, *err_next;
	unsigned long flags;
	struct pci_bus_ops *bus_ops;

	misc_deregister(&aer_inject_device);

	while ((bus_ops = pci_bus_ops_pop())) {
		pci_bus_set_ops(bus_ops->bus, bus_ops->ops);
		kfree(bus_ops);
	}

	spin_lock_irqsave(&inject_lock, flags);
	list_for_each_entry_safe(err, err_next, &einjected, list) {
		list_del(&err->list);
		kfree(err);
	}
	spin_unlock_irqrestore(&inject_lock, flags);
}

module_init(aer_inject_init);
module_exit(aer_inject_exit);

MODULE_DESCRIPTION("PCIe AER software error injector");
MODULE_LICENSE("GPL");