xref: /linux/drivers/pci/pci-sysfs.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * (C) Copyright 2002-2004 Greg Kroah-Hartman <greg@kroah.com>
4  * (C) Copyright 2002-2004 IBM Corp.
5  * (C) Copyright 2003 Matthew Wilcox
6  * (C) Copyright 2003 Hewlett-Packard
7  * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
8  * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
9  *
10  * File attributes for PCI devices
11  *
12  * Modeled after usb's driverfs.c
13  */
14 
15 #include <linux/bitfield.h>
16 #include <linux/kernel.h>
17 #include <linux/sched.h>
18 #include <linux/pci.h>
19 #include <linux/stat.h>
20 #include <linux/export.h>
21 #include <linux/topology.h>
22 #include <linux/mm.h>
23 #include <linux/fs.h>
24 #include <linux/capability.h>
25 #include <linux/security.h>
26 #include <linux/slab.h>
27 #include <linux/vgaarb.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/msi.h>
30 #include <linux/of.h>
31 #include <linux/aperture.h>
32 #include "pci.h"
33 
34 #ifndef ARCH_PCI_DEV_GROUPS
35 #define ARCH_PCI_DEV_GROUPS
36 #endif
37 
38 static int sysfs_initialized;	/* = 0 */
39 
40 /* show configuration fields */
41 #define pci_config_attr(field, format_string)				\
42 static ssize_t								\
43 field##_show(struct device *dev, struct device_attribute *attr, char *buf)				\
44 {									\
45 	struct pci_dev *pdev;						\
46 									\
47 	pdev = to_pci_dev(dev);						\
48 	return sysfs_emit(buf, format_string, pdev->field);		\
49 }									\
50 static DEVICE_ATTR_RO(field)
51 
52 pci_config_attr(vendor, "0x%04x\n");
53 pci_config_attr(device, "0x%04x\n");
54 pci_config_attr(subsystem_vendor, "0x%04x\n");
55 pci_config_attr(subsystem_device, "0x%04x\n");
56 pci_config_attr(revision, "0x%02x\n");
57 pci_config_attr(class, "0x%06x\n");
58 
59 static ssize_t irq_show(struct device *dev,
60 			struct device_attribute *attr,
61 			char *buf)
62 {
63 	struct pci_dev *pdev = to_pci_dev(dev);
64 
65 #ifdef CONFIG_PCI_MSI
66 	/*
67 	 * For MSI, show the first MSI IRQ; for all other cases including
68 	 * MSI-X, show the legacy INTx IRQ.
69 	 */
70 	if (pdev->msi_enabled)
71 		return sysfs_emit(buf, "%u\n", pci_irq_vector(pdev, 0));
72 #endif
73 
74 	return sysfs_emit(buf, "%u\n", pdev->irq);
75 }
76 static DEVICE_ATTR_RO(irq);
77 
78 static ssize_t broken_parity_status_show(struct device *dev,
79 					 struct device_attribute *attr,
80 					 char *buf)
81 {
82 	struct pci_dev *pdev = to_pci_dev(dev);
83 	return sysfs_emit(buf, "%u\n", pdev->broken_parity_status);
84 }
85 
86 static ssize_t broken_parity_status_store(struct device *dev,
87 					  struct device_attribute *attr,
88 					  const char *buf, size_t count)
89 {
90 	struct pci_dev *pdev = to_pci_dev(dev);
91 	unsigned long val;
92 
93 	if (kstrtoul(buf, 0, &val) < 0)
94 		return -EINVAL;
95 
96 	pdev->broken_parity_status = !!val;
97 
98 	return count;
99 }
100 static DEVICE_ATTR_RW(broken_parity_status);
101 
102 static ssize_t pci_dev_show_local_cpu(struct device *dev, bool list,
103 				      struct device_attribute *attr, char *buf)
104 {
105 	const struct cpumask *mask;
106 
107 #ifdef CONFIG_NUMA
108 	if (dev_to_node(dev) == NUMA_NO_NODE)
109 		mask = cpu_online_mask;
110 	else
111 		mask = cpumask_of_node(dev_to_node(dev));
112 #else
113 	mask = cpumask_of_pcibus(to_pci_dev(dev)->bus);
114 #endif
115 	return cpumap_print_to_pagebuf(list, buf, mask);
116 }
117 
118 static ssize_t local_cpus_show(struct device *dev,
119 			       struct device_attribute *attr, char *buf)
120 {
121 	return pci_dev_show_local_cpu(dev, false, attr, buf);
122 }
123 static DEVICE_ATTR_RO(local_cpus);
124 
125 static ssize_t local_cpulist_show(struct device *dev,
126 				  struct device_attribute *attr, char *buf)
127 {
128 	return pci_dev_show_local_cpu(dev, true, attr, buf);
129 }
130 static DEVICE_ATTR_RO(local_cpulist);
131 
132 /*
133  * PCI Bus Class Devices
134  */
135 static ssize_t cpuaffinity_show(struct device *dev,
136 				struct device_attribute *attr, char *buf)
137 {
138 	const struct cpumask *cpumask = cpumask_of_pcibus(to_pci_bus(dev));
139 
140 	return cpumap_print_to_pagebuf(false, buf, cpumask);
141 }
142 static DEVICE_ATTR_RO(cpuaffinity);
143 
144 static ssize_t cpulistaffinity_show(struct device *dev,
145 				    struct device_attribute *attr, char *buf)
146 {
147 	const struct cpumask *cpumask = cpumask_of_pcibus(to_pci_bus(dev));
148 
149 	return cpumap_print_to_pagebuf(true, buf, cpumask);
150 }
151 static DEVICE_ATTR_RO(cpulistaffinity);
152 
153 static ssize_t power_state_show(struct device *dev,
154 				struct device_attribute *attr, char *buf)
155 {
156 	struct pci_dev *pdev = to_pci_dev(dev);
157 
158 	return sysfs_emit(buf, "%s\n", pci_power_name(pdev->current_state));
159 }
160 static DEVICE_ATTR_RO(power_state);
161 
162 /* show resources */
163 static ssize_t resource_show(struct device *dev, struct device_attribute *attr,
164 			     char *buf)
165 {
166 	struct pci_dev *pci_dev = to_pci_dev(dev);
167 	int i;
168 	int max;
169 	resource_size_t start, end;
170 	size_t len = 0;
171 
172 	if (pci_dev->subordinate)
173 		max = DEVICE_COUNT_RESOURCE;
174 	else
175 		max = PCI_BRIDGE_RESOURCES;
176 
177 	for (i = 0; i < max; i++) {
178 		struct resource *res =  &pci_dev->resource[i];
179 		pci_resource_to_user(pci_dev, i, res, &start, &end);
180 		len += sysfs_emit_at(buf, len, "0x%016llx 0x%016llx 0x%016llx\n",
181 				     (unsigned long long)start,
182 				     (unsigned long long)end,
183 				     (unsigned long long)res->flags);
184 	}
185 	return len;
186 }
187 static DEVICE_ATTR_RO(resource);
188 
189 static ssize_t max_link_speed_show(struct device *dev,
190 				   struct device_attribute *attr, char *buf)
191 {
192 	struct pci_dev *pdev = to_pci_dev(dev);
193 
194 	return sysfs_emit(buf, "%s\n",
195 			  pci_speed_string(pcie_get_speed_cap(pdev)));
196 }
197 static DEVICE_ATTR_RO(max_link_speed);
198 
199 static ssize_t max_link_width_show(struct device *dev,
200 				   struct device_attribute *attr, char *buf)
201 {
202 	struct pci_dev *pdev = to_pci_dev(dev);
203 
204 	return sysfs_emit(buf, "%u\n", pcie_get_width_cap(pdev));
205 }
206 static DEVICE_ATTR_RO(max_link_width);
207 
208 static ssize_t current_link_speed_show(struct device *dev,
209 				       struct device_attribute *attr, char *buf)
210 {
211 	struct pci_dev *pci_dev = to_pci_dev(dev);
212 	u16 linkstat;
213 	int err;
214 	enum pci_bus_speed speed;
215 
216 	err = pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &linkstat);
217 	if (err)
218 		return -EINVAL;
219 
220 	speed = pcie_link_speed[linkstat & PCI_EXP_LNKSTA_CLS];
221 
222 	return sysfs_emit(buf, "%s\n", pci_speed_string(speed));
223 }
224 static DEVICE_ATTR_RO(current_link_speed);
225 
226 static ssize_t current_link_width_show(struct device *dev,
227 				       struct device_attribute *attr, char *buf)
228 {
229 	struct pci_dev *pci_dev = to_pci_dev(dev);
230 	u16 linkstat;
231 	int err;
232 
233 	err = pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &linkstat);
234 	if (err)
235 		return -EINVAL;
236 
237 	return sysfs_emit(buf, "%u\n", FIELD_GET(PCI_EXP_LNKSTA_NLW, linkstat));
238 }
239 static DEVICE_ATTR_RO(current_link_width);
240 
241 static ssize_t secondary_bus_number_show(struct device *dev,
242 					 struct device_attribute *attr,
243 					 char *buf)
244 {
245 	struct pci_dev *pci_dev = to_pci_dev(dev);
246 	u8 sec_bus;
247 	int err;
248 
249 	err = pci_read_config_byte(pci_dev, PCI_SECONDARY_BUS, &sec_bus);
250 	if (err)
251 		return -EINVAL;
252 
253 	return sysfs_emit(buf, "%u\n", sec_bus);
254 }
255 static DEVICE_ATTR_RO(secondary_bus_number);
256 
257 static ssize_t subordinate_bus_number_show(struct device *dev,
258 					   struct device_attribute *attr,
259 					   char *buf)
260 {
261 	struct pci_dev *pci_dev = to_pci_dev(dev);
262 	u8 sub_bus;
263 	int err;
264 
265 	err = pci_read_config_byte(pci_dev, PCI_SUBORDINATE_BUS, &sub_bus);
266 	if (err)
267 		return -EINVAL;
268 
269 	return sysfs_emit(buf, "%u\n", sub_bus);
270 }
271 static DEVICE_ATTR_RO(subordinate_bus_number);
272 
273 static ssize_t ari_enabled_show(struct device *dev,
274 				struct device_attribute *attr,
275 				char *buf)
276 {
277 	struct pci_dev *pci_dev = to_pci_dev(dev);
278 
279 	return sysfs_emit(buf, "%u\n", pci_ari_enabled(pci_dev->bus));
280 }
281 static DEVICE_ATTR_RO(ari_enabled);
282 
283 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
284 			     char *buf)
285 {
286 	struct pci_dev *pci_dev = to_pci_dev(dev);
287 
288 	return sysfs_emit(buf, "pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X\n",
289 			  pci_dev->vendor, pci_dev->device,
290 			  pci_dev->subsystem_vendor, pci_dev->subsystem_device,
291 			  (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8),
292 			  (u8)(pci_dev->class));
293 }
294 static DEVICE_ATTR_RO(modalias);
295 
296 static ssize_t enable_store(struct device *dev, struct device_attribute *attr,
297 			     const char *buf, size_t count)
298 {
299 	struct pci_dev *pdev = to_pci_dev(dev);
300 	unsigned long val;
301 	ssize_t result = 0;
302 
303 	/* this can crash the machine when done on the "wrong" device */
304 	if (!capable(CAP_SYS_ADMIN))
305 		return -EPERM;
306 
307 	if (kstrtoul(buf, 0, &val) < 0)
308 		return -EINVAL;
309 
310 	device_lock(dev);
311 	if (dev->driver)
312 		result = -EBUSY;
313 	else if (val)
314 		result = pci_enable_device(pdev);
315 	else if (pci_is_enabled(pdev))
316 		pci_disable_device(pdev);
317 	else
318 		result = -EIO;
319 	device_unlock(dev);
320 
321 	return result < 0 ? result : count;
322 }
323 
324 static ssize_t enable_show(struct device *dev, struct device_attribute *attr,
325 			    char *buf)
326 {
327 	struct pci_dev *pdev;
328 
329 	pdev = to_pci_dev(dev);
330 	return sysfs_emit(buf, "%u\n", atomic_read(&pdev->enable_cnt));
331 }
332 static DEVICE_ATTR_RW(enable);
333 
334 #ifdef CONFIG_NUMA
335 static ssize_t numa_node_store(struct device *dev,
336 			       struct device_attribute *attr, const char *buf,
337 			       size_t count)
338 {
339 	struct pci_dev *pdev = to_pci_dev(dev);
340 	int node;
341 
342 	if (!capable(CAP_SYS_ADMIN))
343 		return -EPERM;
344 
345 	if (kstrtoint(buf, 0, &node) < 0)
346 		return -EINVAL;
347 
348 	if ((node < 0 && node != NUMA_NO_NODE) || node >= MAX_NUMNODES)
349 		return -EINVAL;
350 
351 	if (node != NUMA_NO_NODE && !node_online(node))
352 		return -EINVAL;
353 
354 	add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
355 	pci_alert(pdev, FW_BUG "Overriding NUMA node to %d.  Contact your vendor for updates.",
356 		  node);
357 
358 	dev->numa_node = node;
359 	return count;
360 }
361 
362 static ssize_t numa_node_show(struct device *dev, struct device_attribute *attr,
363 			      char *buf)
364 {
365 	return sysfs_emit(buf, "%d\n", dev->numa_node);
366 }
367 static DEVICE_ATTR_RW(numa_node);
368 #endif
369 
370 static ssize_t dma_mask_bits_show(struct device *dev,
371 				  struct device_attribute *attr, char *buf)
372 {
373 	struct pci_dev *pdev = to_pci_dev(dev);
374 
375 	return sysfs_emit(buf, "%d\n", fls64(pdev->dma_mask));
376 }
377 static DEVICE_ATTR_RO(dma_mask_bits);
378 
379 static ssize_t consistent_dma_mask_bits_show(struct device *dev,
380 					     struct device_attribute *attr,
381 					     char *buf)
382 {
383 	return sysfs_emit(buf, "%d\n", fls64(dev->coherent_dma_mask));
384 }
385 static DEVICE_ATTR_RO(consistent_dma_mask_bits);
386 
387 static ssize_t msi_bus_show(struct device *dev, struct device_attribute *attr,
388 			    char *buf)
389 {
390 	struct pci_dev *pdev = to_pci_dev(dev);
391 	struct pci_bus *subordinate = pdev->subordinate;
392 
393 	return sysfs_emit(buf, "%u\n", subordinate ?
394 			  !(subordinate->bus_flags & PCI_BUS_FLAGS_NO_MSI)
395 			    : !pdev->no_msi);
396 }
397 
398 static ssize_t msi_bus_store(struct device *dev, struct device_attribute *attr,
399 			     const char *buf, size_t count)
400 {
401 	struct pci_dev *pdev = to_pci_dev(dev);
402 	struct pci_bus *subordinate = pdev->subordinate;
403 	unsigned long val;
404 
405 	if (!capable(CAP_SYS_ADMIN))
406 		return -EPERM;
407 
408 	if (kstrtoul(buf, 0, &val) < 0)
409 		return -EINVAL;
410 
411 	/*
412 	 * "no_msi" and "bus_flags" only affect what happens when a driver
413 	 * requests MSI or MSI-X.  They don't affect any drivers that have
414 	 * already requested MSI or MSI-X.
415 	 */
416 	if (!subordinate) {
417 		pdev->no_msi = !val;
418 		pci_info(pdev, "MSI/MSI-X %s for future drivers\n",
419 			 val ? "allowed" : "disallowed");
420 		return count;
421 	}
422 
423 	if (val)
424 		subordinate->bus_flags &= ~PCI_BUS_FLAGS_NO_MSI;
425 	else
426 		subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
427 
428 	dev_info(&subordinate->dev, "MSI/MSI-X %s for future drivers of devices on this bus\n",
429 		 val ? "allowed" : "disallowed");
430 	return count;
431 }
432 static DEVICE_ATTR_RW(msi_bus);
433 
434 static ssize_t rescan_store(const struct bus_type *bus, const char *buf, size_t count)
435 {
436 	unsigned long val;
437 	struct pci_bus *b = NULL;
438 
439 	if (kstrtoul(buf, 0, &val) < 0)
440 		return -EINVAL;
441 
442 	if (val) {
443 		pci_lock_rescan_remove();
444 		while ((b = pci_find_next_bus(b)) != NULL)
445 			pci_rescan_bus(b);
446 		pci_unlock_rescan_remove();
447 	}
448 	return count;
449 }
450 static BUS_ATTR_WO(rescan);
451 
452 static struct attribute *pci_bus_attrs[] = {
453 	&bus_attr_rescan.attr,
454 	NULL,
455 };
456 
457 static const struct attribute_group pci_bus_group = {
458 	.attrs = pci_bus_attrs,
459 };
460 
461 const struct attribute_group *pci_bus_groups[] = {
462 	&pci_bus_group,
463 	NULL,
464 };
465 
466 static ssize_t dev_rescan_store(struct device *dev,
467 				struct device_attribute *attr, const char *buf,
468 				size_t count)
469 {
470 	unsigned long val;
471 	struct pci_dev *pdev = to_pci_dev(dev);
472 
473 	if (kstrtoul(buf, 0, &val) < 0)
474 		return -EINVAL;
475 
476 	if (val) {
477 		pci_lock_rescan_remove();
478 		pci_rescan_bus(pdev->bus);
479 		pci_unlock_rescan_remove();
480 	}
481 	return count;
482 }
483 static struct device_attribute dev_attr_dev_rescan = __ATTR(rescan, 0200, NULL,
484 							    dev_rescan_store);
485 
486 static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
487 			    const char *buf, size_t count)
488 {
489 	unsigned long val;
490 
491 	if (kstrtoul(buf, 0, &val) < 0)
492 		return -EINVAL;
493 
494 	if (val && device_remove_file_self(dev, attr))
495 		pci_stop_and_remove_bus_device_locked(to_pci_dev(dev));
496 	return count;
497 }
498 static DEVICE_ATTR_IGNORE_LOCKDEP(remove, 0220, NULL,
499 				  remove_store);
500 
501 static ssize_t bus_rescan_store(struct device *dev,
502 				struct device_attribute *attr,
503 				const char *buf, size_t count)
504 {
505 	unsigned long val;
506 	struct pci_bus *bus = to_pci_bus(dev);
507 
508 	if (kstrtoul(buf, 0, &val) < 0)
509 		return -EINVAL;
510 
511 	if (val) {
512 		pci_lock_rescan_remove();
513 		if (!pci_is_root_bus(bus) && list_empty(&bus->devices))
514 			pci_rescan_bus_bridge_resize(bus->self);
515 		else
516 			pci_rescan_bus(bus);
517 		pci_unlock_rescan_remove();
518 	}
519 	return count;
520 }
521 static struct device_attribute dev_attr_bus_rescan = __ATTR(rescan, 0200, NULL,
522 							    bus_rescan_store);
523 
524 #if defined(CONFIG_PM) && defined(CONFIG_ACPI)
525 static ssize_t d3cold_allowed_store(struct device *dev,
526 				    struct device_attribute *attr,
527 				    const char *buf, size_t count)
528 {
529 	struct pci_dev *pdev = to_pci_dev(dev);
530 	unsigned long val;
531 
532 	if (kstrtoul(buf, 0, &val) < 0)
533 		return -EINVAL;
534 
535 	pdev->d3cold_allowed = !!val;
536 	pci_bridge_d3_update(pdev);
537 
538 	pm_runtime_resume(dev);
539 
540 	return count;
541 }
542 
543 static ssize_t d3cold_allowed_show(struct device *dev,
544 				   struct device_attribute *attr, char *buf)
545 {
546 	struct pci_dev *pdev = to_pci_dev(dev);
547 	return sysfs_emit(buf, "%u\n", pdev->d3cold_allowed);
548 }
549 static DEVICE_ATTR_RW(d3cold_allowed);
550 #endif
551 
552 #ifdef CONFIG_OF
553 static ssize_t devspec_show(struct device *dev,
554 			    struct device_attribute *attr, char *buf)
555 {
556 	struct pci_dev *pdev = to_pci_dev(dev);
557 	struct device_node *np = pci_device_to_OF_node(pdev);
558 
559 	if (np == NULL)
560 		return 0;
561 	return sysfs_emit(buf, "%pOF\n", np);
562 }
563 static DEVICE_ATTR_RO(devspec);
564 #endif
565 
566 static ssize_t driver_override_store(struct device *dev,
567 				     struct device_attribute *attr,
568 				     const char *buf, size_t count)
569 {
570 	struct pci_dev *pdev = to_pci_dev(dev);
571 	int ret;
572 
573 	ret = driver_set_override(dev, &pdev->driver_override, buf, count);
574 	if (ret)
575 		return ret;
576 
577 	return count;
578 }
579 
580 static ssize_t driver_override_show(struct device *dev,
581 				    struct device_attribute *attr, char *buf)
582 {
583 	struct pci_dev *pdev = to_pci_dev(dev);
584 	ssize_t len;
585 
586 	device_lock(dev);
587 	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
588 	device_unlock(dev);
589 	return len;
590 }
591 static DEVICE_ATTR_RW(driver_override);
592 
593 static struct attribute *pci_dev_attrs[] = {
594 	&dev_attr_power_state.attr,
595 	&dev_attr_resource.attr,
596 	&dev_attr_vendor.attr,
597 	&dev_attr_device.attr,
598 	&dev_attr_subsystem_vendor.attr,
599 	&dev_attr_subsystem_device.attr,
600 	&dev_attr_revision.attr,
601 	&dev_attr_class.attr,
602 	&dev_attr_irq.attr,
603 	&dev_attr_local_cpus.attr,
604 	&dev_attr_local_cpulist.attr,
605 	&dev_attr_modalias.attr,
606 #ifdef CONFIG_NUMA
607 	&dev_attr_numa_node.attr,
608 #endif
609 	&dev_attr_dma_mask_bits.attr,
610 	&dev_attr_consistent_dma_mask_bits.attr,
611 	&dev_attr_enable.attr,
612 	&dev_attr_broken_parity_status.attr,
613 	&dev_attr_msi_bus.attr,
614 #if defined(CONFIG_PM) && defined(CONFIG_ACPI)
615 	&dev_attr_d3cold_allowed.attr,
616 #endif
617 #ifdef CONFIG_OF
618 	&dev_attr_devspec.attr,
619 #endif
620 	&dev_attr_driver_override.attr,
621 	&dev_attr_ari_enabled.attr,
622 	NULL,
623 };
624 
625 static struct attribute *pci_bridge_attrs[] = {
626 	&dev_attr_subordinate_bus_number.attr,
627 	&dev_attr_secondary_bus_number.attr,
628 	NULL,
629 };
630 
631 static struct attribute *pcie_dev_attrs[] = {
632 	&dev_attr_current_link_speed.attr,
633 	&dev_attr_current_link_width.attr,
634 	&dev_attr_max_link_width.attr,
635 	&dev_attr_max_link_speed.attr,
636 	NULL,
637 };
638 
639 static struct attribute *pcibus_attrs[] = {
640 	&dev_attr_bus_rescan.attr,
641 	&dev_attr_cpuaffinity.attr,
642 	&dev_attr_cpulistaffinity.attr,
643 	NULL,
644 };
645 
646 static const struct attribute_group pcibus_group = {
647 	.attrs = pcibus_attrs,
648 };
649 
650 const struct attribute_group *pcibus_groups[] = {
651 	&pcibus_group,
652 	NULL,
653 };
654 
655 static ssize_t boot_vga_show(struct device *dev, struct device_attribute *attr,
656 			     char *buf)
657 {
658 	struct pci_dev *pdev = to_pci_dev(dev);
659 	struct pci_dev *vga_dev = vga_default_device();
660 
661 	if (vga_dev)
662 		return sysfs_emit(buf, "%u\n", (pdev == vga_dev));
663 
664 	return sysfs_emit(buf, "%u\n",
665 			  !!(pdev->resource[PCI_ROM_RESOURCE].flags &
666 			     IORESOURCE_ROM_SHADOW));
667 }
668 static DEVICE_ATTR_RO(boot_vga);
669 
670 static ssize_t pci_read_config(struct file *filp, struct kobject *kobj,
671 			       struct bin_attribute *bin_attr, char *buf,
672 			       loff_t off, size_t count)
673 {
674 	struct pci_dev *dev = to_pci_dev(kobj_to_dev(kobj));
675 	unsigned int size = 64;
676 	loff_t init_off = off;
677 	u8 *data = (u8 *) buf;
678 
679 	/* Several chips lock up trying to read undefined config space */
680 	if (file_ns_capable(filp, &init_user_ns, CAP_SYS_ADMIN))
681 		size = dev->cfg_size;
682 	else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
683 		size = 128;
684 
685 	if (off > size)
686 		return 0;
687 	if (off + count > size) {
688 		size -= off;
689 		count = size;
690 	} else {
691 		size = count;
692 	}
693 
694 	pci_config_pm_runtime_get(dev);
695 
696 	if ((off & 1) && size) {
697 		u8 val;
698 		pci_user_read_config_byte(dev, off, &val);
699 		data[off - init_off] = val;
700 		off++;
701 		size--;
702 	}
703 
704 	if ((off & 3) && size > 2) {
705 		u16 val;
706 		pci_user_read_config_word(dev, off, &val);
707 		data[off - init_off] = val & 0xff;
708 		data[off - init_off + 1] = (val >> 8) & 0xff;
709 		off += 2;
710 		size -= 2;
711 	}
712 
713 	while (size > 3) {
714 		u32 val;
715 		pci_user_read_config_dword(dev, off, &val);
716 		data[off - init_off] = val & 0xff;
717 		data[off - init_off + 1] = (val >> 8) & 0xff;
718 		data[off - init_off + 2] = (val >> 16) & 0xff;
719 		data[off - init_off + 3] = (val >> 24) & 0xff;
720 		off += 4;
721 		size -= 4;
722 		cond_resched();
723 	}
724 
725 	if (size >= 2) {
726 		u16 val;
727 		pci_user_read_config_word(dev, off, &val);
728 		data[off - init_off] = val & 0xff;
729 		data[off - init_off + 1] = (val >> 8) & 0xff;
730 		off += 2;
731 		size -= 2;
732 	}
733 
734 	if (size > 0) {
735 		u8 val;
736 		pci_user_read_config_byte(dev, off, &val);
737 		data[off - init_off] = val;
738 	}
739 
740 	pci_config_pm_runtime_put(dev);
741 
742 	return count;
743 }
744 
745 static ssize_t pci_write_config(struct file *filp, struct kobject *kobj,
746 				struct bin_attribute *bin_attr, char *buf,
747 				loff_t off, size_t count)
748 {
749 	struct pci_dev *dev = to_pci_dev(kobj_to_dev(kobj));
750 	unsigned int size = count;
751 	loff_t init_off = off;
752 	u8 *data = (u8 *) buf;
753 	int ret;
754 
755 	ret = security_locked_down(LOCKDOWN_PCI_ACCESS);
756 	if (ret)
757 		return ret;
758 
759 	if (resource_is_exclusive(&dev->driver_exclusive_resource, off,
760 				  count)) {
761 		pci_warn_once(dev, "%s: Unexpected write to kernel-exclusive config offset %llx",
762 			      current->comm, off);
763 		add_taint(TAINT_USER, LOCKDEP_STILL_OK);
764 	}
765 
766 	if (off > dev->cfg_size)
767 		return 0;
768 	if (off + count > dev->cfg_size) {
769 		size = dev->cfg_size - off;
770 		count = size;
771 	}
772 
773 	pci_config_pm_runtime_get(dev);
774 
775 	if ((off & 1) && size) {
776 		pci_user_write_config_byte(dev, off, data[off - init_off]);
777 		off++;
778 		size--;
779 	}
780 
781 	if ((off & 3) && size > 2) {
782 		u16 val = data[off - init_off];
783 		val |= (u16) data[off - init_off + 1] << 8;
784 		pci_user_write_config_word(dev, off, val);
785 		off += 2;
786 		size -= 2;
787 	}
788 
789 	while (size > 3) {
790 		u32 val = data[off - init_off];
791 		val |= (u32) data[off - init_off + 1] << 8;
792 		val |= (u32) data[off - init_off + 2] << 16;
793 		val |= (u32) data[off - init_off + 3] << 24;
794 		pci_user_write_config_dword(dev, off, val);
795 		off += 4;
796 		size -= 4;
797 	}
798 
799 	if (size >= 2) {
800 		u16 val = data[off - init_off];
801 		val |= (u16) data[off - init_off + 1] << 8;
802 		pci_user_write_config_word(dev, off, val);
803 		off += 2;
804 		size -= 2;
805 	}
806 
807 	if (size)
808 		pci_user_write_config_byte(dev, off, data[off - init_off]);
809 
810 	pci_config_pm_runtime_put(dev);
811 
812 	return count;
813 }
814 static BIN_ATTR(config, 0644, pci_read_config, pci_write_config, 0);
815 
816 static struct bin_attribute *pci_dev_config_attrs[] = {
817 	&bin_attr_config,
818 	NULL,
819 };
820 
821 static umode_t pci_dev_config_attr_is_visible(struct kobject *kobj,
822 					      struct bin_attribute *a, int n)
823 {
824 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
825 
826 	a->size = PCI_CFG_SPACE_SIZE;
827 	if (pdev->cfg_size > PCI_CFG_SPACE_SIZE)
828 		a->size = PCI_CFG_SPACE_EXP_SIZE;
829 
830 	return a->attr.mode;
831 }
832 
833 static const struct attribute_group pci_dev_config_attr_group = {
834 	.bin_attrs = pci_dev_config_attrs,
835 	.is_bin_visible = pci_dev_config_attr_is_visible,
836 };
837 
838 /*
839  * llseek operation for mmappable PCI resources.
840  * May be left unused if the arch doesn't provide them.
841  */
842 static __maybe_unused loff_t
843 pci_llseek_resource(struct file *filep,
844 		    struct kobject *kobj __always_unused,
845 		    struct bin_attribute *attr,
846 		    loff_t offset, int whence)
847 {
848 	return fixed_size_llseek(filep, offset, whence, attr->size);
849 }
850 
851 #ifdef HAVE_PCI_LEGACY
852 /**
853  * pci_read_legacy_io - read byte(s) from legacy I/O port space
854  * @filp: open sysfs file
855  * @kobj: kobject corresponding to file to read from
856  * @bin_attr: struct bin_attribute for this file
857  * @buf: buffer to store results
858  * @off: offset into legacy I/O port space
859  * @count: number of bytes to read
860  *
861  * Reads 1, 2, or 4 bytes from legacy I/O port space using an arch specific
862  * callback routine (pci_legacy_read).
863  */
864 static ssize_t pci_read_legacy_io(struct file *filp, struct kobject *kobj,
865 				  struct bin_attribute *bin_attr, char *buf,
866 				  loff_t off, size_t count)
867 {
868 	struct pci_bus *bus = to_pci_bus(kobj_to_dev(kobj));
869 
870 	/* Only support 1, 2 or 4 byte accesses */
871 	if (count != 1 && count != 2 && count != 4)
872 		return -EINVAL;
873 
874 	return pci_legacy_read(bus, off, (u32 *)buf, count);
875 }
876 
877 /**
878  * pci_write_legacy_io - write byte(s) to legacy I/O port space
879  * @filp: open sysfs file
880  * @kobj: kobject corresponding to file to read from
881  * @bin_attr: struct bin_attribute for this file
882  * @buf: buffer containing value to be written
883  * @off: offset into legacy I/O port space
884  * @count: number of bytes to write
885  *
886  * Writes 1, 2, or 4 bytes from legacy I/O port space using an arch specific
887  * callback routine (pci_legacy_write).
888  */
889 static ssize_t pci_write_legacy_io(struct file *filp, struct kobject *kobj,
890 				   struct bin_attribute *bin_attr, char *buf,
891 				   loff_t off, size_t count)
892 {
893 	struct pci_bus *bus = to_pci_bus(kobj_to_dev(kobj));
894 
895 	/* Only support 1, 2 or 4 byte accesses */
896 	if (count != 1 && count != 2 && count != 4)
897 		return -EINVAL;
898 
899 	return pci_legacy_write(bus, off, *(u32 *)buf, count);
900 }
901 
902 /**
903  * pci_mmap_legacy_mem - map legacy PCI memory into user memory space
904  * @filp: open sysfs file
905  * @kobj: kobject corresponding to device to be mapped
906  * @attr: struct bin_attribute for this file
907  * @vma: struct vm_area_struct passed to mmap
908  *
909  * Uses an arch specific callback, pci_mmap_legacy_mem_page_range, to mmap
910  * legacy memory space (first meg of bus space) into application virtual
911  * memory space.
912  */
913 static int pci_mmap_legacy_mem(struct file *filp, struct kobject *kobj,
914 			       struct bin_attribute *attr,
915 			       struct vm_area_struct *vma)
916 {
917 	struct pci_bus *bus = to_pci_bus(kobj_to_dev(kobj));
918 
919 	return pci_mmap_legacy_page_range(bus, vma, pci_mmap_mem);
920 }
921 
922 /**
923  * pci_mmap_legacy_io - map legacy PCI IO into user memory space
924  * @filp: open sysfs file
925  * @kobj: kobject corresponding to device to be mapped
926  * @attr: struct bin_attribute for this file
927  * @vma: struct vm_area_struct passed to mmap
928  *
929  * Uses an arch specific callback, pci_mmap_legacy_io_page_range, to mmap
930  * legacy IO space (first meg of bus space) into application virtual
931  * memory space. Returns -ENOSYS if the operation isn't supported
932  */
933 static int pci_mmap_legacy_io(struct file *filp, struct kobject *kobj,
934 			      struct bin_attribute *attr,
935 			      struct vm_area_struct *vma)
936 {
937 	struct pci_bus *bus = to_pci_bus(kobj_to_dev(kobj));
938 
939 	return pci_mmap_legacy_page_range(bus, vma, pci_mmap_io);
940 }
941 
942 /**
943  * pci_adjust_legacy_attr - adjustment of legacy file attributes
944  * @b: bus to create files under
945  * @mmap_type: I/O port or memory
946  *
947  * Stub implementation. Can be overridden by arch if necessary.
948  */
949 void __weak pci_adjust_legacy_attr(struct pci_bus *b,
950 				   enum pci_mmap_state mmap_type)
951 {
952 }
953 
954 /**
955  * pci_create_legacy_files - create legacy I/O port and memory files
956  * @b: bus to create files under
957  *
958  * Some platforms allow access to legacy I/O port and ISA memory space on
959  * a per-bus basis.  This routine creates the files and ties them into
960  * their associated read, write and mmap files from pci-sysfs.c
961  *
962  * On error unwind, but don't propagate the error to the caller
963  * as it is ok to set up the PCI bus without these files.
964  */
965 void pci_create_legacy_files(struct pci_bus *b)
966 {
967 	int error;
968 
969 	if (!sysfs_initialized)
970 		return;
971 
972 	b->legacy_io = kcalloc(2, sizeof(struct bin_attribute),
973 			       GFP_ATOMIC);
974 	if (!b->legacy_io)
975 		goto kzalloc_err;
976 
977 	sysfs_bin_attr_init(b->legacy_io);
978 	b->legacy_io->attr.name = "legacy_io";
979 	b->legacy_io->size = 0xffff;
980 	b->legacy_io->attr.mode = 0600;
981 	b->legacy_io->read = pci_read_legacy_io;
982 	b->legacy_io->write = pci_write_legacy_io;
983 	/* See pci_create_attr() for motivation */
984 	b->legacy_io->llseek = pci_llseek_resource;
985 	b->legacy_io->mmap = pci_mmap_legacy_io;
986 	b->legacy_io->f_mapping = iomem_get_mapping;
987 	pci_adjust_legacy_attr(b, pci_mmap_io);
988 	error = device_create_bin_file(&b->dev, b->legacy_io);
989 	if (error)
990 		goto legacy_io_err;
991 
992 	/* Allocated above after the legacy_io struct */
993 	b->legacy_mem = b->legacy_io + 1;
994 	sysfs_bin_attr_init(b->legacy_mem);
995 	b->legacy_mem->attr.name = "legacy_mem";
996 	b->legacy_mem->size = 1024*1024;
997 	b->legacy_mem->attr.mode = 0600;
998 	b->legacy_mem->mmap = pci_mmap_legacy_mem;
999 	/* See pci_create_attr() for motivation */
1000 	b->legacy_mem->llseek = pci_llseek_resource;
1001 	b->legacy_mem->f_mapping = iomem_get_mapping;
1002 	pci_adjust_legacy_attr(b, pci_mmap_mem);
1003 	error = device_create_bin_file(&b->dev, b->legacy_mem);
1004 	if (error)
1005 		goto legacy_mem_err;
1006 
1007 	return;
1008 
1009 legacy_mem_err:
1010 	device_remove_bin_file(&b->dev, b->legacy_io);
1011 legacy_io_err:
1012 	kfree(b->legacy_io);
1013 	b->legacy_io = NULL;
1014 kzalloc_err:
1015 	dev_warn(&b->dev, "could not create legacy I/O port and ISA memory resources in sysfs\n");
1016 }
1017 
1018 void pci_remove_legacy_files(struct pci_bus *b)
1019 {
1020 	if (b->legacy_io) {
1021 		device_remove_bin_file(&b->dev, b->legacy_io);
1022 		device_remove_bin_file(&b->dev, b->legacy_mem);
1023 		kfree(b->legacy_io); /* both are allocated here */
1024 	}
1025 }
1026 #endif /* HAVE_PCI_LEGACY */
1027 
1028 #if defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE)
1029 /**
1030  * pci_mmap_resource - map a PCI resource into user memory space
1031  * @kobj: kobject for mapping
1032  * @attr: struct bin_attribute for the file being mapped
1033  * @vma: struct vm_area_struct passed into the mmap
1034  * @write_combine: 1 for write_combine mapping
1035  *
1036  * Use the regular PCI mapping routines to map a PCI resource into userspace.
1037  */
1038 static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
1039 			     struct vm_area_struct *vma, int write_combine)
1040 {
1041 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
1042 	int bar = (unsigned long)attr->private;
1043 	enum pci_mmap_state mmap_type;
1044 	struct resource *res = &pdev->resource[bar];
1045 	int ret;
1046 
1047 	ret = security_locked_down(LOCKDOWN_PCI_ACCESS);
1048 	if (ret)
1049 		return ret;
1050 
1051 	if (res->flags & IORESOURCE_MEM && iomem_is_exclusive(res->start))
1052 		return -EINVAL;
1053 
1054 	if (!pci_mmap_fits(pdev, bar, vma, PCI_MMAP_SYSFS))
1055 		return -EINVAL;
1056 
1057 	mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
1058 
1059 	return pci_mmap_resource_range(pdev, bar, vma, mmap_type, write_combine);
1060 }
1061 
1062 static int pci_mmap_resource_uc(struct file *filp, struct kobject *kobj,
1063 				struct bin_attribute *attr,
1064 				struct vm_area_struct *vma)
1065 {
1066 	return pci_mmap_resource(kobj, attr, vma, 0);
1067 }
1068 
1069 static int pci_mmap_resource_wc(struct file *filp, struct kobject *kobj,
1070 				struct bin_attribute *attr,
1071 				struct vm_area_struct *vma)
1072 {
1073 	return pci_mmap_resource(kobj, attr, vma, 1);
1074 }
1075 
1076 static ssize_t pci_resource_io(struct file *filp, struct kobject *kobj,
1077 			       struct bin_attribute *attr, char *buf,
1078 			       loff_t off, size_t count, bool write)
1079 {
1080 #ifdef CONFIG_HAS_IOPORT
1081 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
1082 	int bar = (unsigned long)attr->private;
1083 	unsigned long port = off;
1084 
1085 	port += pci_resource_start(pdev, bar);
1086 
1087 	if (port > pci_resource_end(pdev, bar))
1088 		return 0;
1089 
1090 	if (port + count - 1 > pci_resource_end(pdev, bar))
1091 		return -EINVAL;
1092 
1093 	switch (count) {
1094 	case 1:
1095 		if (write)
1096 			outb(*(u8 *)buf, port);
1097 		else
1098 			*(u8 *)buf = inb(port);
1099 		return 1;
1100 	case 2:
1101 		if (write)
1102 			outw(*(u16 *)buf, port);
1103 		else
1104 			*(u16 *)buf = inw(port);
1105 		return 2;
1106 	case 4:
1107 		if (write)
1108 			outl(*(u32 *)buf, port);
1109 		else
1110 			*(u32 *)buf = inl(port);
1111 		return 4;
1112 	}
1113 	return -EINVAL;
1114 #else
1115 	return -ENXIO;
1116 #endif
1117 }
1118 
1119 static ssize_t pci_read_resource_io(struct file *filp, struct kobject *kobj,
1120 				    struct bin_attribute *attr, char *buf,
1121 				    loff_t off, size_t count)
1122 {
1123 	return pci_resource_io(filp, kobj, attr, buf, off, count, false);
1124 }
1125 
1126 static ssize_t pci_write_resource_io(struct file *filp, struct kobject *kobj,
1127 				     struct bin_attribute *attr, char *buf,
1128 				     loff_t off, size_t count)
1129 {
1130 	int ret;
1131 
1132 	ret = security_locked_down(LOCKDOWN_PCI_ACCESS);
1133 	if (ret)
1134 		return ret;
1135 
1136 	return pci_resource_io(filp, kobj, attr, buf, off, count, true);
1137 }
1138 
1139 /**
1140  * pci_remove_resource_files - cleanup resource files
1141  * @pdev: dev to cleanup
1142  *
1143  * If we created resource files for @pdev, remove them from sysfs and
1144  * free their resources.
1145  */
1146 static void pci_remove_resource_files(struct pci_dev *pdev)
1147 {
1148 	int i;
1149 
1150 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
1151 		struct bin_attribute *res_attr;
1152 
1153 		res_attr = pdev->res_attr[i];
1154 		if (res_attr) {
1155 			sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
1156 			kfree(res_attr);
1157 		}
1158 
1159 		res_attr = pdev->res_attr_wc[i];
1160 		if (res_attr) {
1161 			sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
1162 			kfree(res_attr);
1163 		}
1164 	}
1165 }
1166 
1167 static int pci_create_attr(struct pci_dev *pdev, int num, int write_combine)
1168 {
1169 	/* allocate attribute structure, piggyback attribute name */
1170 	int name_len = write_combine ? 13 : 10;
1171 	struct bin_attribute *res_attr;
1172 	char *res_attr_name;
1173 	int retval;
1174 
1175 	res_attr = kzalloc(sizeof(*res_attr) + name_len, GFP_ATOMIC);
1176 	if (!res_attr)
1177 		return -ENOMEM;
1178 
1179 	res_attr_name = (char *)(res_attr + 1);
1180 
1181 	sysfs_bin_attr_init(res_attr);
1182 	if (write_combine) {
1183 		sprintf(res_attr_name, "resource%d_wc", num);
1184 		res_attr->mmap = pci_mmap_resource_wc;
1185 	} else {
1186 		sprintf(res_attr_name, "resource%d", num);
1187 		if (pci_resource_flags(pdev, num) & IORESOURCE_IO) {
1188 			res_attr->read = pci_read_resource_io;
1189 			res_attr->write = pci_write_resource_io;
1190 			if (arch_can_pci_mmap_io())
1191 				res_attr->mmap = pci_mmap_resource_uc;
1192 		} else {
1193 			res_attr->mmap = pci_mmap_resource_uc;
1194 		}
1195 	}
1196 	if (res_attr->mmap) {
1197 		res_attr->f_mapping = iomem_get_mapping;
1198 		/*
1199 		 * generic_file_llseek() consults f_mapping->host to determine
1200 		 * the file size. As iomem_inode knows nothing about the
1201 		 * attribute, it's not going to work, so override it as well.
1202 		 */
1203 		res_attr->llseek = pci_llseek_resource;
1204 	}
1205 	res_attr->attr.name = res_attr_name;
1206 	res_attr->attr.mode = 0600;
1207 	res_attr->size = pci_resource_len(pdev, num);
1208 	res_attr->private = (void *)(unsigned long)num;
1209 	retval = sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
1210 	if (retval) {
1211 		kfree(res_attr);
1212 		return retval;
1213 	}
1214 
1215 	if (write_combine)
1216 		pdev->res_attr_wc[num] = res_attr;
1217 	else
1218 		pdev->res_attr[num] = res_attr;
1219 
1220 	return 0;
1221 }
1222 
1223 /**
1224  * pci_create_resource_files - create resource files in sysfs for @dev
1225  * @pdev: dev in question
1226  *
1227  * Walk the resources in @pdev creating files for each resource available.
1228  */
1229 static int pci_create_resource_files(struct pci_dev *pdev)
1230 {
1231 	int i;
1232 	int retval;
1233 
1234 	/* Expose the PCI resources from this device as files */
1235 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
1236 
1237 		/* skip empty resources */
1238 		if (!pci_resource_len(pdev, i))
1239 			continue;
1240 
1241 		retval = pci_create_attr(pdev, i, 0);
1242 		/* for prefetchable resources, create a WC mappable file */
1243 		if (!retval && arch_can_pci_mmap_wc() &&
1244 		    pdev->resource[i].flags & IORESOURCE_PREFETCH)
1245 			retval = pci_create_attr(pdev, i, 1);
1246 		if (retval) {
1247 			pci_remove_resource_files(pdev);
1248 			return retval;
1249 		}
1250 	}
1251 	return 0;
1252 }
1253 #else /* !(defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE)) */
1254 int __weak pci_create_resource_files(struct pci_dev *dev) { return 0; }
1255 void __weak pci_remove_resource_files(struct pci_dev *dev) { return; }
1256 #endif
1257 
1258 /**
1259  * pci_write_rom - used to enable access to the PCI ROM display
1260  * @filp: sysfs file
1261  * @kobj: kernel object handle
1262  * @bin_attr: struct bin_attribute for this file
1263  * @buf: user input
1264  * @off: file offset
1265  * @count: number of byte in input
1266  *
1267  * writing anything except 0 enables it
1268  */
1269 static ssize_t pci_write_rom(struct file *filp, struct kobject *kobj,
1270 			     struct bin_attribute *bin_attr, char *buf,
1271 			     loff_t off, size_t count)
1272 {
1273 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
1274 
1275 	if ((off ==  0) && (*buf == '0') && (count == 2))
1276 		pdev->rom_attr_enabled = 0;
1277 	else
1278 		pdev->rom_attr_enabled = 1;
1279 
1280 	return count;
1281 }
1282 
1283 /**
1284  * pci_read_rom - read a PCI ROM
1285  * @filp: sysfs file
1286  * @kobj: kernel object handle
1287  * @bin_attr: struct bin_attribute for this file
1288  * @buf: where to put the data we read from the ROM
1289  * @off: file offset
1290  * @count: number of bytes to read
1291  *
1292  * Put @count bytes starting at @off into @buf from the ROM in the PCI
1293  * device corresponding to @kobj.
1294  */
1295 static ssize_t pci_read_rom(struct file *filp, struct kobject *kobj,
1296 			    struct bin_attribute *bin_attr, char *buf,
1297 			    loff_t off, size_t count)
1298 {
1299 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
1300 	void __iomem *rom;
1301 	size_t size;
1302 
1303 	if (!pdev->rom_attr_enabled)
1304 		return -EINVAL;
1305 
1306 	rom = pci_map_rom(pdev, &size);	/* size starts out as PCI window size */
1307 	if (!rom || !size)
1308 		return -EIO;
1309 
1310 	if (off >= size)
1311 		count = 0;
1312 	else {
1313 		if (off + count > size)
1314 			count = size - off;
1315 
1316 		memcpy_fromio(buf, rom + off, count);
1317 	}
1318 	pci_unmap_rom(pdev, rom);
1319 
1320 	return count;
1321 }
1322 static BIN_ATTR(rom, 0600, pci_read_rom, pci_write_rom, 0);
1323 
1324 static struct bin_attribute *pci_dev_rom_attrs[] = {
1325 	&bin_attr_rom,
1326 	NULL,
1327 };
1328 
1329 static umode_t pci_dev_rom_attr_is_visible(struct kobject *kobj,
1330 					   struct bin_attribute *a, int n)
1331 {
1332 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
1333 	size_t rom_size;
1334 
1335 	/* If the device has a ROM, try to expose it in sysfs. */
1336 	rom_size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
1337 	if (!rom_size)
1338 		return 0;
1339 
1340 	a->size = rom_size;
1341 
1342 	return a->attr.mode;
1343 }
1344 
1345 static const struct attribute_group pci_dev_rom_attr_group = {
1346 	.bin_attrs = pci_dev_rom_attrs,
1347 	.is_bin_visible = pci_dev_rom_attr_is_visible,
1348 };
1349 
1350 static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
1351 			   const char *buf, size_t count)
1352 {
1353 	struct pci_dev *pdev = to_pci_dev(dev);
1354 	unsigned long val;
1355 	ssize_t result;
1356 
1357 	if (kstrtoul(buf, 0, &val) < 0)
1358 		return -EINVAL;
1359 
1360 	if (val != 1)
1361 		return -EINVAL;
1362 
1363 	pm_runtime_get_sync(dev);
1364 	result = pci_reset_function(pdev);
1365 	pm_runtime_put(dev);
1366 	if (result < 0)
1367 		return result;
1368 
1369 	return count;
1370 }
1371 static DEVICE_ATTR_WO(reset);
1372 
1373 static struct attribute *pci_dev_reset_attrs[] = {
1374 	&dev_attr_reset.attr,
1375 	NULL,
1376 };
1377 
1378 static umode_t pci_dev_reset_attr_is_visible(struct kobject *kobj,
1379 					     struct attribute *a, int n)
1380 {
1381 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
1382 
1383 	if (!pci_reset_supported(pdev))
1384 		return 0;
1385 
1386 	return a->mode;
1387 }
1388 
1389 static const struct attribute_group pci_dev_reset_attr_group = {
1390 	.attrs = pci_dev_reset_attrs,
1391 	.is_visible = pci_dev_reset_attr_is_visible,
1392 };
1393 
1394 static ssize_t __resource_resize_show(struct device *dev, int n, char *buf)
1395 {
1396 	struct pci_dev *pdev = to_pci_dev(dev);
1397 	ssize_t ret;
1398 
1399 	pci_config_pm_runtime_get(pdev);
1400 
1401 	ret = sysfs_emit(buf, "%016llx\n",
1402 			 (u64)pci_rebar_get_possible_sizes(pdev, n));
1403 
1404 	pci_config_pm_runtime_put(pdev);
1405 
1406 	return ret;
1407 }
1408 
1409 static ssize_t __resource_resize_store(struct device *dev, int n,
1410 				       const char *buf, size_t count)
1411 {
1412 	struct pci_dev *pdev = to_pci_dev(dev);
1413 	unsigned long size, flags;
1414 	int ret, i;
1415 	u16 cmd;
1416 
1417 	if (kstrtoul(buf, 0, &size) < 0)
1418 		return -EINVAL;
1419 
1420 	device_lock(dev);
1421 	if (dev->driver) {
1422 		ret = -EBUSY;
1423 		goto unlock;
1424 	}
1425 
1426 	pci_config_pm_runtime_get(pdev);
1427 
1428 	if ((pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA) {
1429 		ret = aperture_remove_conflicting_pci_devices(pdev,
1430 						"resourceN_resize");
1431 		if (ret)
1432 			goto pm_put;
1433 	}
1434 
1435 	pci_read_config_word(pdev, PCI_COMMAND, &cmd);
1436 	pci_write_config_word(pdev, PCI_COMMAND,
1437 			      cmd & ~PCI_COMMAND_MEMORY);
1438 
1439 	flags = pci_resource_flags(pdev, n);
1440 
1441 	pci_remove_resource_files(pdev);
1442 
1443 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
1444 		if (pci_resource_len(pdev, i) &&
1445 		    pci_resource_flags(pdev, i) == flags)
1446 			pci_release_resource(pdev, i);
1447 	}
1448 
1449 	ret = pci_resize_resource(pdev, n, size);
1450 
1451 	pci_assign_unassigned_bus_resources(pdev->bus);
1452 
1453 	if (pci_create_resource_files(pdev))
1454 		pci_warn(pdev, "Failed to recreate resource files after BAR resizing\n");
1455 
1456 	pci_write_config_word(pdev, PCI_COMMAND, cmd);
1457 pm_put:
1458 	pci_config_pm_runtime_put(pdev);
1459 unlock:
1460 	device_unlock(dev);
1461 
1462 	return ret ? ret : count;
1463 }
1464 
1465 #define pci_dev_resource_resize_attr(n)					\
1466 static ssize_t resource##n##_resize_show(struct device *dev,		\
1467 					 struct device_attribute *attr,	\
1468 					 char *buf)			\
1469 {									\
1470 	return __resource_resize_show(dev, n, buf);			\
1471 }									\
1472 static ssize_t resource##n##_resize_store(struct device *dev,		\
1473 					  struct device_attribute *attr,\
1474 					  const char *buf, size_t count)\
1475 {									\
1476 	return __resource_resize_store(dev, n, buf, count);		\
1477 }									\
1478 static DEVICE_ATTR_RW(resource##n##_resize)
1479 
1480 pci_dev_resource_resize_attr(0);
1481 pci_dev_resource_resize_attr(1);
1482 pci_dev_resource_resize_attr(2);
1483 pci_dev_resource_resize_attr(3);
1484 pci_dev_resource_resize_attr(4);
1485 pci_dev_resource_resize_attr(5);
1486 
1487 static struct attribute *resource_resize_attrs[] = {
1488 	&dev_attr_resource0_resize.attr,
1489 	&dev_attr_resource1_resize.attr,
1490 	&dev_attr_resource2_resize.attr,
1491 	&dev_attr_resource3_resize.attr,
1492 	&dev_attr_resource4_resize.attr,
1493 	&dev_attr_resource5_resize.attr,
1494 	NULL,
1495 };
1496 
1497 static umode_t resource_resize_is_visible(struct kobject *kobj,
1498 					  struct attribute *a, int n)
1499 {
1500 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
1501 
1502 	return pci_rebar_get_current_size(pdev, n) < 0 ? 0 : a->mode;
1503 }
1504 
1505 static const struct attribute_group pci_dev_resource_resize_group = {
1506 	.attrs = resource_resize_attrs,
1507 	.is_visible = resource_resize_is_visible,
1508 };
1509 
1510 int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev)
1511 {
1512 	if (!sysfs_initialized)
1513 		return -EACCES;
1514 
1515 	return pci_create_resource_files(pdev);
1516 }
1517 
1518 /**
1519  * pci_remove_sysfs_dev_files - cleanup PCI specific sysfs files
1520  * @pdev: device whose entries we should free
1521  *
1522  * Cleanup when @pdev is removed from sysfs.
1523  */
1524 void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
1525 {
1526 	if (!sysfs_initialized)
1527 		return;
1528 
1529 	pci_remove_resource_files(pdev);
1530 }
1531 
1532 static int __init pci_sysfs_init(void)
1533 {
1534 	struct pci_dev *pdev = NULL;
1535 	struct pci_bus *pbus = NULL;
1536 	int retval;
1537 
1538 	sysfs_initialized = 1;
1539 	for_each_pci_dev(pdev) {
1540 		retval = pci_create_sysfs_dev_files(pdev);
1541 		if (retval) {
1542 			pci_dev_put(pdev);
1543 			return retval;
1544 		}
1545 	}
1546 
1547 	while ((pbus = pci_find_next_bus(pbus)))
1548 		pci_create_legacy_files(pbus);
1549 
1550 	return 0;
1551 }
1552 late_initcall(pci_sysfs_init);
1553 
1554 static struct attribute *pci_dev_dev_attrs[] = {
1555 	&dev_attr_boot_vga.attr,
1556 	NULL,
1557 };
1558 
1559 static umode_t pci_dev_attrs_are_visible(struct kobject *kobj,
1560 					 struct attribute *a, int n)
1561 {
1562 	struct device *dev = kobj_to_dev(kobj);
1563 	struct pci_dev *pdev = to_pci_dev(dev);
1564 
1565 	if (a == &dev_attr_boot_vga.attr && pci_is_vga(pdev))
1566 		return a->mode;
1567 
1568 	return 0;
1569 }
1570 
1571 static struct attribute *pci_dev_hp_attrs[] = {
1572 	&dev_attr_remove.attr,
1573 	&dev_attr_dev_rescan.attr,
1574 	NULL,
1575 };
1576 
1577 static umode_t pci_dev_hp_attrs_are_visible(struct kobject *kobj,
1578 					    struct attribute *a, int n)
1579 {
1580 	struct device *dev = kobj_to_dev(kobj);
1581 	struct pci_dev *pdev = to_pci_dev(dev);
1582 
1583 	if (pdev->is_virtfn)
1584 		return 0;
1585 
1586 	return a->mode;
1587 }
1588 
1589 static umode_t pci_bridge_attrs_are_visible(struct kobject *kobj,
1590 					    struct attribute *a, int n)
1591 {
1592 	struct device *dev = kobj_to_dev(kobj);
1593 	struct pci_dev *pdev = to_pci_dev(dev);
1594 
1595 	if (pci_is_bridge(pdev))
1596 		return a->mode;
1597 
1598 	return 0;
1599 }
1600 
1601 static umode_t pcie_dev_attrs_are_visible(struct kobject *kobj,
1602 					  struct attribute *a, int n)
1603 {
1604 	struct device *dev = kobj_to_dev(kobj);
1605 	struct pci_dev *pdev = to_pci_dev(dev);
1606 
1607 	if (pci_is_pcie(pdev))
1608 		return a->mode;
1609 
1610 	return 0;
1611 }
1612 
1613 static const struct attribute_group pci_dev_group = {
1614 	.attrs = pci_dev_attrs,
1615 };
1616 
1617 const struct attribute_group *pci_dev_groups[] = {
1618 	&pci_dev_group,
1619 	&pci_dev_config_attr_group,
1620 	&pci_dev_rom_attr_group,
1621 	&pci_dev_reset_attr_group,
1622 	&pci_dev_reset_method_attr_group,
1623 	&pci_dev_vpd_attr_group,
1624 #ifdef CONFIG_DMI
1625 	&pci_dev_smbios_attr_group,
1626 #endif
1627 #ifdef CONFIG_ACPI
1628 	&pci_dev_acpi_attr_group,
1629 #endif
1630 	&pci_dev_resource_resize_group,
1631 	ARCH_PCI_DEV_GROUPS
1632 	NULL,
1633 };
1634 
1635 static const struct attribute_group pci_dev_hp_attr_group = {
1636 	.attrs = pci_dev_hp_attrs,
1637 	.is_visible = pci_dev_hp_attrs_are_visible,
1638 };
1639 
1640 static const struct attribute_group pci_dev_attr_group = {
1641 	.attrs = pci_dev_dev_attrs,
1642 	.is_visible = pci_dev_attrs_are_visible,
1643 };
1644 
1645 static const struct attribute_group pci_bridge_attr_group = {
1646 	.attrs = pci_bridge_attrs,
1647 	.is_visible = pci_bridge_attrs_are_visible,
1648 };
1649 
1650 static const struct attribute_group pcie_dev_attr_group = {
1651 	.attrs = pcie_dev_attrs,
1652 	.is_visible = pcie_dev_attrs_are_visible,
1653 };
1654 
1655 const struct attribute_group *pci_dev_attr_groups[] = {
1656 	&pci_dev_attr_group,
1657 	&pci_dev_hp_attr_group,
1658 #ifdef CONFIG_PCI_IOV
1659 	&sriov_pf_dev_attr_group,
1660 	&sriov_vf_dev_attr_group,
1661 #endif
1662 	&pci_bridge_attr_group,
1663 	&pcie_dev_attr_group,
1664 #ifdef CONFIG_PCIEAER
1665 	&aer_stats_attr_group,
1666 #endif
1667 #ifdef CONFIG_PCIEASPM
1668 	&aspm_ctrl_attr_group,
1669 #endif
1670 	NULL,
1671 };
1672