xref: /openbmc/linux/drivers/pci/pci-sysfs.c (revision 9ac8d3fb)
1 /*
2  * drivers/pci/pci-sysfs.c
3  *
4  * (C) Copyright 2002-2004 Greg Kroah-Hartman <greg@kroah.com>
5  * (C) Copyright 2002-2004 IBM Corp.
6  * (C) Copyright 2003 Matthew Wilcox
7  * (C) Copyright 2003 Hewlett-Packard
8  * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
9  * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
10  *
11  * File attributes for PCI devices
12  *
13  * Modeled after usb's driverfs.c
14  *
15  */
16 
17 
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/pci.h>
21 #include <linux/stat.h>
22 #include <linux/topology.h>
23 #include <linux/mm.h>
24 #include <linux/capability.h>
25 #include <linux/pci-aspm.h>
26 #include "pci.h"
27 
28 static int sysfs_initialized;	/* = 0 */
29 
30 /* show configuration fields */
31 #define pci_config_attr(field, format_string)				\
32 static ssize_t								\
33 field##_show(struct device *dev, struct device_attribute *attr, char *buf)				\
34 {									\
35 	struct pci_dev *pdev;						\
36 									\
37 	pdev = to_pci_dev (dev);					\
38 	return sprintf (buf, format_string, pdev->field);		\
39 }
40 
41 pci_config_attr(vendor, "0x%04x\n");
42 pci_config_attr(device, "0x%04x\n");
43 pci_config_attr(subsystem_vendor, "0x%04x\n");
44 pci_config_attr(subsystem_device, "0x%04x\n");
45 pci_config_attr(class, "0x%06x\n");
46 pci_config_attr(irq, "%u\n");
47 
48 static ssize_t broken_parity_status_show(struct device *dev,
49 					 struct device_attribute *attr,
50 					 char *buf)
51 {
52 	struct pci_dev *pdev = to_pci_dev(dev);
53 	return sprintf (buf, "%u\n", pdev->broken_parity_status);
54 }
55 
56 static ssize_t broken_parity_status_store(struct device *dev,
57 					  struct device_attribute *attr,
58 					  const char *buf, size_t count)
59 {
60 	struct pci_dev *pdev = to_pci_dev(dev);
61 	ssize_t consumed = -EINVAL;
62 
63 	if ((count > 0) && (*buf == '0' || *buf == '1')) {
64 		pdev->broken_parity_status = *buf == '1' ? 1 : 0;
65 		consumed = count;
66 	}
67 	return consumed;
68 }
69 
70 static ssize_t local_cpus_show(struct device *dev,
71 			struct device_attribute *attr, char *buf)
72 {
73 	cpumask_t mask;
74 	int len;
75 
76 	mask = pcibus_to_cpumask(to_pci_dev(dev)->bus);
77 	len = cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
78 	buf[len++] = '\n';
79 	buf[len] = '\0';
80 	return len;
81 }
82 
83 
84 static ssize_t local_cpulist_show(struct device *dev,
85 			struct device_attribute *attr, char *buf)
86 {
87 	cpumask_t mask;
88 	int len;
89 
90 	mask = pcibus_to_cpumask(to_pci_dev(dev)->bus);
91 	len = cpulist_scnprintf(buf, PAGE_SIZE-2, mask);
92 	buf[len++] = '\n';
93 	buf[len] = '\0';
94 	return len;
95 }
96 
97 /* show resources */
98 static ssize_t
99 resource_show(struct device * dev, struct device_attribute *attr, char * buf)
100 {
101 	struct pci_dev * pci_dev = to_pci_dev(dev);
102 	char * str = buf;
103 	int i;
104 	int max = 7;
105 	resource_size_t start, end;
106 
107 	if (pci_dev->subordinate)
108 		max = DEVICE_COUNT_RESOURCE;
109 
110 	for (i = 0; i < max; i++) {
111 		struct resource *res =  &pci_dev->resource[i];
112 		pci_resource_to_user(pci_dev, i, res, &start, &end);
113 		str += sprintf(str,"0x%016llx 0x%016llx 0x%016llx\n",
114 			       (unsigned long long)start,
115 			       (unsigned long long)end,
116 			       (unsigned long long)res->flags);
117 	}
118 	return (str - buf);
119 }
120 
121 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
122 {
123 	struct pci_dev *pci_dev = to_pci_dev(dev);
124 
125 	return sprintf(buf, "pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02x\n",
126 		       pci_dev->vendor, pci_dev->device,
127 		       pci_dev->subsystem_vendor, pci_dev->subsystem_device,
128 		       (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8),
129 		       (u8)(pci_dev->class));
130 }
131 
132 static ssize_t is_enabled_store(struct device *dev,
133 				struct device_attribute *attr, const char *buf,
134 				size_t count)
135 {
136 	ssize_t result = -EINVAL;
137 	struct pci_dev *pdev = to_pci_dev(dev);
138 
139 	/* this can crash the machine when done on the "wrong" device */
140 	if (!capable(CAP_SYS_ADMIN))
141 		return count;
142 
143 	if (*buf == '0') {
144 		if (atomic_read(&pdev->enable_cnt) != 0)
145 			pci_disable_device(pdev);
146 		else
147 			result = -EIO;
148 	} else if (*buf == '1')
149 		result = pci_enable_device(pdev);
150 
151 	return result < 0 ? result : count;
152 }
153 
154 static ssize_t is_enabled_show(struct device *dev,
155 			       struct device_attribute *attr, char *buf)
156 {
157 	struct pci_dev *pdev;
158 
159 	pdev = to_pci_dev (dev);
160 	return sprintf (buf, "%u\n", atomic_read(&pdev->enable_cnt));
161 }
162 
163 #ifdef CONFIG_NUMA
164 static ssize_t
165 numa_node_show(struct device *dev, struct device_attribute *attr, char *buf)
166 {
167 	return sprintf (buf, "%d\n", dev->numa_node);
168 }
169 #endif
170 
171 static ssize_t
172 msi_bus_show(struct device *dev, struct device_attribute *attr, char *buf)
173 {
174 	struct pci_dev *pdev = to_pci_dev(dev);
175 
176 	if (!pdev->subordinate)
177 		return 0;
178 
179 	return sprintf (buf, "%u\n",
180 			!(pdev->subordinate->bus_flags & PCI_BUS_FLAGS_NO_MSI));
181 }
182 
183 static ssize_t
184 msi_bus_store(struct device *dev, struct device_attribute *attr,
185 	      const char *buf, size_t count)
186 {
187 	struct pci_dev *pdev = to_pci_dev(dev);
188 
189 	/* bad things may happen if the no_msi flag is changed
190 	 * while some drivers are loaded */
191 	if (!capable(CAP_SYS_ADMIN))
192 		return count;
193 
194 	if (!pdev->subordinate)
195 		return count;
196 
197 	if (*buf == '0') {
198 		pdev->subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
199 		dev_warn(&pdev->dev, "forced subordinate bus to not support MSI,"
200 			 " bad things could happen.\n");
201 	}
202 
203 	if (*buf == '1') {
204 		pdev->subordinate->bus_flags &= ~PCI_BUS_FLAGS_NO_MSI;
205 		dev_warn(&pdev->dev, "forced subordinate bus to support MSI,"
206 			 " bad things could happen.\n");
207 	}
208 
209 	return count;
210 }
211 
212 struct device_attribute pci_dev_attrs[] = {
213 	__ATTR_RO(resource),
214 	__ATTR_RO(vendor),
215 	__ATTR_RO(device),
216 	__ATTR_RO(subsystem_vendor),
217 	__ATTR_RO(subsystem_device),
218 	__ATTR_RO(class),
219 	__ATTR_RO(irq),
220 	__ATTR_RO(local_cpus),
221 	__ATTR_RO(local_cpulist),
222 	__ATTR_RO(modalias),
223 #ifdef CONFIG_NUMA
224 	__ATTR_RO(numa_node),
225 #endif
226 	__ATTR(enable, 0600, is_enabled_show, is_enabled_store),
227 	__ATTR(broken_parity_status,(S_IRUGO|S_IWUSR),
228 		broken_parity_status_show,broken_parity_status_store),
229 	__ATTR(msi_bus, 0644, msi_bus_show, msi_bus_store),
230 	__ATTR_NULL,
231 };
232 
233 static ssize_t
234 pci_read_config(struct kobject *kobj, struct bin_attribute *bin_attr,
235 		char *buf, loff_t off, size_t count)
236 {
237 	struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
238 	unsigned int size = 64;
239 	loff_t init_off = off;
240 	u8 *data = (u8*) buf;
241 
242 	/* Several chips lock up trying to read undefined config space */
243 	if (capable(CAP_SYS_ADMIN)) {
244 		size = dev->cfg_size;
245 	} else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
246 		size = 128;
247 	}
248 
249 	if (off > size)
250 		return 0;
251 	if (off + count > size) {
252 		size -= off;
253 		count = size;
254 	} else {
255 		size = count;
256 	}
257 
258 	if ((off & 1) && size) {
259 		u8 val;
260 		pci_user_read_config_byte(dev, off, &val);
261 		data[off - init_off] = val;
262 		off++;
263 		size--;
264 	}
265 
266 	if ((off & 3) && size > 2) {
267 		u16 val;
268 		pci_user_read_config_word(dev, off, &val);
269 		data[off - init_off] = val & 0xff;
270 		data[off - init_off + 1] = (val >> 8) & 0xff;
271 		off += 2;
272 		size -= 2;
273 	}
274 
275 	while (size > 3) {
276 		u32 val;
277 		pci_user_read_config_dword(dev, off, &val);
278 		data[off - init_off] = val & 0xff;
279 		data[off - init_off + 1] = (val >> 8) & 0xff;
280 		data[off - init_off + 2] = (val >> 16) & 0xff;
281 		data[off - init_off + 3] = (val >> 24) & 0xff;
282 		off += 4;
283 		size -= 4;
284 	}
285 
286 	if (size >= 2) {
287 		u16 val;
288 		pci_user_read_config_word(dev, off, &val);
289 		data[off - init_off] = val & 0xff;
290 		data[off - init_off + 1] = (val >> 8) & 0xff;
291 		off += 2;
292 		size -= 2;
293 	}
294 
295 	if (size > 0) {
296 		u8 val;
297 		pci_user_read_config_byte(dev, off, &val);
298 		data[off - init_off] = val;
299 		off++;
300 		--size;
301 	}
302 
303 	return count;
304 }
305 
306 static ssize_t
307 pci_write_config(struct kobject *kobj, struct bin_attribute *bin_attr,
308 		 char *buf, loff_t off, size_t count)
309 {
310 	struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
311 	unsigned int size = count;
312 	loff_t init_off = off;
313 	u8 *data = (u8*) buf;
314 
315 	if (off > dev->cfg_size)
316 		return 0;
317 	if (off + count > dev->cfg_size) {
318 		size = dev->cfg_size - off;
319 		count = size;
320 	}
321 
322 	if ((off & 1) && size) {
323 		pci_user_write_config_byte(dev, off, data[off - init_off]);
324 		off++;
325 		size--;
326 	}
327 
328 	if ((off & 3) && size > 2) {
329 		u16 val = data[off - init_off];
330 		val |= (u16) data[off - init_off + 1] << 8;
331                 pci_user_write_config_word(dev, off, val);
332                 off += 2;
333                 size -= 2;
334         }
335 
336 	while (size > 3) {
337 		u32 val = data[off - init_off];
338 		val |= (u32) data[off - init_off + 1] << 8;
339 		val |= (u32) data[off - init_off + 2] << 16;
340 		val |= (u32) data[off - init_off + 3] << 24;
341 		pci_user_write_config_dword(dev, off, val);
342 		off += 4;
343 		size -= 4;
344 	}
345 
346 	if (size >= 2) {
347 		u16 val = data[off - init_off];
348 		val |= (u16) data[off - init_off + 1] << 8;
349 		pci_user_write_config_word(dev, off, val);
350 		off += 2;
351 		size -= 2;
352 	}
353 
354 	if (size) {
355 		pci_user_write_config_byte(dev, off, data[off - init_off]);
356 		off++;
357 		--size;
358 	}
359 
360 	return count;
361 }
362 
363 static ssize_t
364 pci_read_vpd(struct kobject *kobj, struct bin_attribute *bin_attr,
365 	     char *buf, loff_t off, size_t count)
366 {
367 	struct pci_dev *dev =
368 		to_pci_dev(container_of(kobj, struct device, kobj));
369 	int end;
370 	int ret;
371 
372 	if (off > bin_attr->size)
373 		count = 0;
374 	else if (count > bin_attr->size - off)
375 		count = bin_attr->size - off;
376 	end = off + count;
377 
378 	while (off < end) {
379 		ret = dev->vpd->ops->read(dev, off, end - off, buf);
380 		if (ret < 0)
381 			return ret;
382 		buf += ret;
383 		off += ret;
384 	}
385 
386 	return count;
387 }
388 
389 static ssize_t
390 pci_write_vpd(struct kobject *kobj, struct bin_attribute *bin_attr,
391 	      char *buf, loff_t off, size_t count)
392 {
393 	struct pci_dev *dev =
394 		to_pci_dev(container_of(kobj, struct device, kobj));
395 	int end;
396 	int ret;
397 
398 	if (off > bin_attr->size)
399 		count = 0;
400 	else if (count > bin_attr->size - off)
401 		count = bin_attr->size - off;
402 	end = off + count;
403 
404 	while (off < end) {
405 		ret = dev->vpd->ops->write(dev, off, end - off, buf);
406 		if (ret < 0)
407 			return ret;
408 		buf += ret;
409 		off += ret;
410 	}
411 
412 	return count;
413 }
414 
415 #ifdef HAVE_PCI_LEGACY
416 /**
417  * pci_read_legacy_io - read byte(s) from legacy I/O port space
418  * @kobj: kobject corresponding to file to read from
419  * @buf: buffer to store results
420  * @off: offset into legacy I/O port space
421  * @count: number of bytes to read
422  *
423  * Reads 1, 2, or 4 bytes from legacy I/O port space using an arch specific
424  * callback routine (pci_legacy_read).
425  */
426 static ssize_t
427 pci_read_legacy_io(struct kobject *kobj, struct bin_attribute *bin_attr,
428 		   char *buf, loff_t off, size_t count)
429 {
430         struct pci_bus *bus = to_pci_bus(container_of(kobj,
431                                                       struct device,
432 						      kobj));
433 
434         /* Only support 1, 2 or 4 byte accesses */
435         if (count != 1 && count != 2 && count != 4)
436                 return -EINVAL;
437 
438         return pci_legacy_read(bus, off, (u32 *)buf, count);
439 }
440 
441 /**
442  * pci_write_legacy_io - write byte(s) to legacy I/O port space
443  * @kobj: kobject corresponding to file to read from
444  * @buf: buffer containing value to be written
445  * @off: offset into legacy I/O port space
446  * @count: number of bytes to write
447  *
448  * Writes 1, 2, or 4 bytes from legacy I/O port space using an arch specific
449  * callback routine (pci_legacy_write).
450  */
451 static ssize_t
452 pci_write_legacy_io(struct kobject *kobj, struct bin_attribute *bin_attr,
453 		    char *buf, loff_t off, size_t count)
454 {
455         struct pci_bus *bus = to_pci_bus(container_of(kobj,
456 						      struct device,
457 						      kobj));
458         /* Only support 1, 2 or 4 byte accesses */
459         if (count != 1 && count != 2 && count != 4)
460                 return -EINVAL;
461 
462         return pci_legacy_write(bus, off, *(u32 *)buf, count);
463 }
464 
465 /**
466  * pci_mmap_legacy_mem - map legacy PCI memory into user memory space
467  * @kobj: kobject corresponding to device to be mapped
468  * @attr: struct bin_attribute for this file
469  * @vma: struct vm_area_struct passed to mmap
470  *
471  * Uses an arch specific callback, pci_mmap_legacy_mem_page_range, to mmap
472  * legacy memory space (first meg of bus space) into application virtual
473  * memory space.
474  */
475 static int
476 pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr,
477                     struct vm_area_struct *vma)
478 {
479         struct pci_bus *bus = to_pci_bus(container_of(kobj,
480                                                       struct device,
481 						      kobj));
482 
483         return pci_mmap_legacy_page_range(bus, vma, pci_mmap_mem);
484 }
485 
486 /**
487  * pci_mmap_legacy_io - map legacy PCI IO into user memory space
488  * @kobj: kobject corresponding to device to be mapped
489  * @attr: struct bin_attribute for this file
490  * @vma: struct vm_area_struct passed to mmap
491  *
492  * Uses an arch specific callback, pci_mmap_legacy_io_page_range, to mmap
493  * legacy IO space (first meg of bus space) into application virtual
494  * memory space. Returns -ENOSYS if the operation isn't supported
495  */
496 static int
497 pci_mmap_legacy_io(struct kobject *kobj, struct bin_attribute *attr,
498 		   struct vm_area_struct *vma)
499 {
500         struct pci_bus *bus = to_pci_bus(container_of(kobj,
501                                                       struct device,
502 						      kobj));
503 
504         return pci_mmap_legacy_page_range(bus, vma, pci_mmap_io);
505 }
506 
507 /**
508  * pci_create_legacy_files - create legacy I/O port and memory files
509  * @b: bus to create files under
510  *
511  * Some platforms allow access to legacy I/O port and ISA memory space on
512  * a per-bus basis.  This routine creates the files and ties them into
513  * their associated read, write and mmap files from pci-sysfs.c
514  *
515  * On error unwind, but don't propogate the error to the caller
516  * as it is ok to set up the PCI bus without these files.
517  */
518 void pci_create_legacy_files(struct pci_bus *b)
519 {
520 	int error;
521 
522 	b->legacy_io = kzalloc(sizeof(struct bin_attribute) * 2,
523 			       GFP_ATOMIC);
524 	if (!b->legacy_io)
525 		goto kzalloc_err;
526 
527 	b->legacy_io->attr.name = "legacy_io";
528 	b->legacy_io->size = 0xffff;
529 	b->legacy_io->attr.mode = S_IRUSR | S_IWUSR;
530 	b->legacy_io->read = pci_read_legacy_io;
531 	b->legacy_io->write = pci_write_legacy_io;
532 	b->legacy_io->mmap = pci_mmap_legacy_io;
533 	error = device_create_bin_file(&b->dev, b->legacy_io);
534 	if (error)
535 		goto legacy_io_err;
536 
537 	/* Allocated above after the legacy_io struct */
538 	b->legacy_mem = b->legacy_io + 1;
539 	b->legacy_mem->attr.name = "legacy_mem";
540 	b->legacy_mem->size = 1024*1024;
541 	b->legacy_mem->attr.mode = S_IRUSR | S_IWUSR;
542 	b->legacy_mem->mmap = pci_mmap_legacy_mem;
543 	error = device_create_bin_file(&b->dev, b->legacy_mem);
544 	if (error)
545 		goto legacy_mem_err;
546 
547 	return;
548 
549 legacy_mem_err:
550 	device_remove_bin_file(&b->dev, b->legacy_io);
551 legacy_io_err:
552 	kfree(b->legacy_io);
553 	b->legacy_io = NULL;
554 kzalloc_err:
555 	printk(KERN_WARNING "pci: warning: could not create legacy I/O port "
556 	       "and ISA memory resources to sysfs\n");
557 	return;
558 }
559 
560 void pci_remove_legacy_files(struct pci_bus *b)
561 {
562 	if (b->legacy_io) {
563 		device_remove_bin_file(&b->dev, b->legacy_io);
564 		device_remove_bin_file(&b->dev, b->legacy_mem);
565 		kfree(b->legacy_io); /* both are allocated here */
566 	}
567 }
568 #endif /* HAVE_PCI_LEGACY */
569 
570 #ifdef HAVE_PCI_MMAP
571 
572 static int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma)
573 {
574 	unsigned long nr, start, size;
575 
576 	nr = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
577 	start = vma->vm_pgoff;
578 	size = pci_resource_len(pdev, resno) >> PAGE_SHIFT;
579 	if (start < size && size - start >= nr)
580 		return 1;
581 	WARN(1, "process \"%s\" tried to map 0x%08lx-0x%08lx on %s BAR %d (size 0x%08lx)\n",
582 		current->comm, start, start+nr, pci_name(pdev), resno, size);
583 	return 0;
584 }
585 
586 /**
587  * pci_mmap_resource - map a PCI resource into user memory space
588  * @kobj: kobject for mapping
589  * @attr: struct bin_attribute for the file being mapped
590  * @vma: struct vm_area_struct passed into the mmap
591  * @write_combine: 1 for write_combine mapping
592  *
593  * Use the regular PCI mapping routines to map a PCI resource into userspace.
594  */
595 static int
596 pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
597 		  struct vm_area_struct *vma, int write_combine)
598 {
599 	struct pci_dev *pdev = to_pci_dev(container_of(kobj,
600 						       struct device, kobj));
601 	struct resource *res = (struct resource *)attr->private;
602 	enum pci_mmap_state mmap_type;
603 	resource_size_t start, end;
604 	int i;
605 
606 	for (i = 0; i < PCI_ROM_RESOURCE; i++)
607 		if (res == &pdev->resource[i])
608 			break;
609 	if (i >= PCI_ROM_RESOURCE)
610 		return -ENODEV;
611 
612 	if (!pci_mmap_fits(pdev, i, vma))
613 		return -EINVAL;
614 
615 	/* pci_mmap_page_range() expects the same kind of entry as coming
616 	 * from /proc/bus/pci/ which is a "user visible" value. If this is
617 	 * different from the resource itself, arch will do necessary fixup.
618 	 */
619 	pci_resource_to_user(pdev, i, res, &start, &end);
620 	vma->vm_pgoff += start >> PAGE_SHIFT;
621 	mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
622 
623 	return pci_mmap_page_range(pdev, vma, mmap_type, write_combine);
624 }
625 
626 static int
627 pci_mmap_resource_uc(struct kobject *kobj, struct bin_attribute *attr,
628 		     struct vm_area_struct *vma)
629 {
630 	return pci_mmap_resource(kobj, attr, vma, 0);
631 }
632 
633 static int
634 pci_mmap_resource_wc(struct kobject *kobj, struct bin_attribute *attr,
635 		     struct vm_area_struct *vma)
636 {
637 	return pci_mmap_resource(kobj, attr, vma, 1);
638 }
639 
640 /**
641  * pci_remove_resource_files - cleanup resource files
642  * @dev: dev to cleanup
643  *
644  * If we created resource files for @dev, remove them from sysfs and
645  * free their resources.
646  */
647 static void
648 pci_remove_resource_files(struct pci_dev *pdev)
649 {
650 	int i;
651 
652 	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
653 		struct bin_attribute *res_attr;
654 
655 		res_attr = pdev->res_attr[i];
656 		if (res_attr) {
657 			sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
658 			kfree(res_attr);
659 		}
660 
661 		res_attr = pdev->res_attr_wc[i];
662 		if (res_attr) {
663 			sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
664 			kfree(res_attr);
665 		}
666 	}
667 }
668 
669 static int pci_create_attr(struct pci_dev *pdev, int num, int write_combine)
670 {
671 	/* allocate attribute structure, piggyback attribute name */
672 	int name_len = write_combine ? 13 : 10;
673 	struct bin_attribute *res_attr;
674 	int retval;
675 
676 	res_attr = kzalloc(sizeof(*res_attr) + name_len, GFP_ATOMIC);
677 	if (res_attr) {
678 		char *res_attr_name = (char *)(res_attr + 1);
679 
680 		if (write_combine) {
681 			pdev->res_attr_wc[num] = res_attr;
682 			sprintf(res_attr_name, "resource%d_wc", num);
683 			res_attr->mmap = pci_mmap_resource_wc;
684 		} else {
685 			pdev->res_attr[num] = res_attr;
686 			sprintf(res_attr_name, "resource%d", num);
687 			res_attr->mmap = pci_mmap_resource_uc;
688 		}
689 		res_attr->attr.name = res_attr_name;
690 		res_attr->attr.mode = S_IRUSR | S_IWUSR;
691 		res_attr->size = pci_resource_len(pdev, num);
692 		res_attr->private = &pdev->resource[num];
693 		retval = sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
694 	} else
695 		retval = -ENOMEM;
696 
697 	return retval;
698 }
699 
700 /**
701  * pci_create_resource_files - create resource files in sysfs for @dev
702  * @dev: dev in question
703  *
704  * Walk the resources in @dev creating files for each resource available.
705  */
706 static int pci_create_resource_files(struct pci_dev *pdev)
707 {
708 	int i;
709 	int retval;
710 
711 	/* Expose the PCI resources from this device as files */
712 	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
713 
714 		/* skip empty resources */
715 		if (!pci_resource_len(pdev, i))
716 			continue;
717 
718 		retval = pci_create_attr(pdev, i, 0);
719 		/* for prefetchable resources, create a WC mappable file */
720 		if (!retval && pdev->resource[i].flags & IORESOURCE_PREFETCH)
721 			retval = pci_create_attr(pdev, i, 1);
722 
723 		if (retval) {
724 			pci_remove_resource_files(pdev);
725 			return retval;
726 		}
727 	}
728 	return 0;
729 }
730 #else /* !HAVE_PCI_MMAP */
731 static inline int pci_create_resource_files(struct pci_dev *dev) { return 0; }
732 static inline void pci_remove_resource_files(struct pci_dev *dev) { return; }
733 #endif /* HAVE_PCI_MMAP */
734 
735 /**
736  * pci_write_rom - used to enable access to the PCI ROM display
737  * @kobj: kernel object handle
738  * @buf: user input
739  * @off: file offset
740  * @count: number of byte in input
741  *
742  * writing anything except 0 enables it
743  */
744 static ssize_t
745 pci_write_rom(struct kobject *kobj, struct bin_attribute *bin_attr,
746 	      char *buf, loff_t off, size_t count)
747 {
748 	struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
749 
750 	if ((off ==  0) && (*buf == '0') && (count == 2))
751 		pdev->rom_attr_enabled = 0;
752 	else
753 		pdev->rom_attr_enabled = 1;
754 
755 	return count;
756 }
757 
758 /**
759  * pci_read_rom - read a PCI ROM
760  * @kobj: kernel object handle
761  * @buf: where to put the data we read from the ROM
762  * @off: file offset
763  * @count: number of bytes to read
764  *
765  * Put @count bytes starting at @off into @buf from the ROM in the PCI
766  * device corresponding to @kobj.
767  */
768 static ssize_t
769 pci_read_rom(struct kobject *kobj, struct bin_attribute *bin_attr,
770 	     char *buf, loff_t off, size_t count)
771 {
772 	struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
773 	void __iomem *rom;
774 	size_t size;
775 
776 	if (!pdev->rom_attr_enabled)
777 		return -EINVAL;
778 
779 	rom = pci_map_rom(pdev, &size);	/* size starts out as PCI window size */
780 	if (!rom)
781 		return 0;
782 
783 	if (off >= size)
784 		count = 0;
785 	else {
786 		if (off + count > size)
787 			count = size - off;
788 
789 		memcpy_fromio(buf, rom + off, count);
790 	}
791 	pci_unmap_rom(pdev, rom);
792 
793 	return count;
794 }
795 
796 static struct bin_attribute pci_config_attr = {
797 	.attr =	{
798 		.name = "config",
799 		.mode = S_IRUGO | S_IWUSR,
800 	},
801 	.size = PCI_CFG_SPACE_SIZE,
802 	.read = pci_read_config,
803 	.write = pci_write_config,
804 };
805 
806 static struct bin_attribute pcie_config_attr = {
807 	.attr =	{
808 		.name = "config",
809 		.mode = S_IRUGO | S_IWUSR,
810 	},
811 	.size = PCI_CFG_SPACE_EXP_SIZE,
812 	.read = pci_read_config,
813 	.write = pci_write_config,
814 };
815 
816 int __attribute__ ((weak)) pcibios_add_platform_entries(struct pci_dev *dev)
817 {
818 	return 0;
819 }
820 
821 static int pci_create_capabilities_sysfs(struct pci_dev *dev)
822 {
823 	int retval;
824 	struct bin_attribute *attr;
825 
826 	/* If the device has VPD, try to expose it in sysfs. */
827 	if (dev->vpd) {
828 		attr = kzalloc(sizeof(*attr), GFP_ATOMIC);
829 		if (!attr)
830 			return -ENOMEM;
831 
832 		attr->size = dev->vpd->len;
833 		attr->attr.name = "vpd";
834 		attr->attr.mode = S_IRUSR | S_IWUSR;
835 		attr->read = pci_read_vpd;
836 		attr->write = pci_write_vpd;
837 		retval = sysfs_create_bin_file(&dev->dev.kobj, attr);
838 		if (retval) {
839 			kfree(dev->vpd->attr);
840 			return retval;
841 		}
842 		dev->vpd->attr = attr;
843 	}
844 
845 	/* Active State Power Management */
846 	pcie_aspm_create_sysfs_dev_files(dev);
847 
848 	return 0;
849 }
850 
851 int __must_check pci_create_sysfs_dev_files (struct pci_dev *pdev)
852 {
853 	int retval;
854 	int rom_size = 0;
855 	struct bin_attribute *attr;
856 
857 	if (!sysfs_initialized)
858 		return -EACCES;
859 
860 	if (pdev->cfg_size < PCI_CFG_SPACE_EXP_SIZE)
861 		retval = sysfs_create_bin_file(&pdev->dev.kobj, &pci_config_attr);
862 	else
863 		retval = sysfs_create_bin_file(&pdev->dev.kobj, &pcie_config_attr);
864 	if (retval)
865 		goto err;
866 
867 	retval = pci_create_resource_files(pdev);
868 	if (retval)
869 		goto err_config_file;
870 
871 	if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
872 		rom_size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
873 	else if (pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW)
874 		rom_size = 0x20000;
875 
876 	/* If the device has a ROM, try to expose it in sysfs. */
877 	if (rom_size) {
878 		attr = kzalloc(sizeof(*attr), GFP_ATOMIC);
879 		if (!attr) {
880 			retval = -ENOMEM;
881 			goto err_resource_files;
882 		}
883 		attr->size = rom_size;
884 		attr->attr.name = "rom";
885 		attr->attr.mode = S_IRUSR;
886 		attr->read = pci_read_rom;
887 		attr->write = pci_write_rom;
888 		retval = sysfs_create_bin_file(&pdev->dev.kobj, attr);
889 		if (retval) {
890 			kfree(attr);
891 			goto err_resource_files;
892 		}
893 		pdev->rom_attr = attr;
894 	}
895 
896 	/* add platform-specific attributes */
897 	retval = pcibios_add_platform_entries(pdev);
898 	if (retval)
899 		goto err_rom_file;
900 
901 	/* add sysfs entries for various capabilities */
902 	retval = pci_create_capabilities_sysfs(pdev);
903 	if (retval)
904 		goto err_rom_file;
905 
906 	return 0;
907 
908 err_rom_file:
909 	if (rom_size) {
910 		sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
911 		kfree(pdev->rom_attr);
912 		pdev->rom_attr = NULL;
913 	}
914 err_resource_files:
915 	pci_remove_resource_files(pdev);
916 err_config_file:
917 	if (pdev->cfg_size < PCI_CFG_SPACE_EXP_SIZE)
918 		sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
919 	else
920 		sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
921 err:
922 	return retval;
923 }
924 
925 static void pci_remove_capabilities_sysfs(struct pci_dev *dev)
926 {
927 	if (dev->vpd && dev->vpd->attr) {
928 		sysfs_remove_bin_file(&dev->dev.kobj, dev->vpd->attr);
929 		kfree(dev->vpd->attr);
930 	}
931 
932 	pcie_aspm_remove_sysfs_dev_files(dev);
933 }
934 
935 /**
936  * pci_remove_sysfs_dev_files - cleanup PCI specific sysfs files
937  * @pdev: device whose entries we should free
938  *
939  * Cleanup when @pdev is removed from sysfs.
940  */
941 void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
942 {
943 	int rom_size = 0;
944 
945 	if (!sysfs_initialized)
946 		return;
947 
948 	pci_remove_capabilities_sysfs(pdev);
949 
950 	if (pdev->cfg_size < PCI_CFG_SPACE_EXP_SIZE)
951 		sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
952 	else
953 		sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
954 
955 	pci_remove_resource_files(pdev);
956 
957 	if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
958 		rom_size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
959 	else if (pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW)
960 		rom_size = 0x20000;
961 
962 	if (rom_size && pdev->rom_attr) {
963 		sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
964 		kfree(pdev->rom_attr);
965 	}
966 }
967 
968 static int __init pci_sysfs_init(void)
969 {
970 	struct pci_dev *pdev = NULL;
971 	int retval;
972 
973 	sysfs_initialized = 1;
974 	for_each_pci_dev(pdev) {
975 		retval = pci_create_sysfs_dev_files(pdev);
976 		if (retval) {
977 			pci_dev_put(pdev);
978 			return retval;
979 		}
980 	}
981 
982 	return 0;
983 }
984 
985 late_initcall(pci_sysfs_init);
986