xref: /linux/drivers/pci/proc.c (revision 384740dc49ea651ba350704d13ff6be9976e37fe)
1 /*
2  *	Procfs interface for the PCI bus.
3  *
4  *	Copyright (c) 1997--1999 Martin Mares <mj@ucw.cz>
5  */
6 
7 #include <linux/init.h>
8 #include <linux/pci.h>
9 #include <linux/module.h>
10 #include <linux/proc_fs.h>
11 #include <linux/seq_file.h>
12 #include <linux/smp_lock.h>
13 #include <linux/capability.h>
14 #include <asm/uaccess.h>
15 #include <asm/byteorder.h>
16 #include "pci.h"
17 
18 static int proc_initialized;	/* = 0 */
19 
20 static loff_t
21 proc_bus_pci_lseek(struct file *file, loff_t off, int whence)
22 {
23 	loff_t new = -1;
24 	struct inode *inode = file->f_path.dentry->d_inode;
25 
26 	mutex_lock(&inode->i_mutex);
27 	switch (whence) {
28 	case 0:
29 		new = off;
30 		break;
31 	case 1:
32 		new = file->f_pos + off;
33 		break;
34 	case 2:
35 		new = inode->i_size + off;
36 		break;
37 	}
38 	if (new < 0 || new > inode->i_size)
39 		new = -EINVAL;
40 	else
41 		file->f_pos = new;
42 	mutex_unlock(&inode->i_mutex);
43 	return new;
44 }
45 
46 static ssize_t
47 proc_bus_pci_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
48 {
49 	const struct inode *ino = file->f_path.dentry->d_inode;
50 	const struct proc_dir_entry *dp = PDE(ino);
51 	struct pci_dev *dev = dp->data;
52 	unsigned int pos = *ppos;
53 	unsigned int cnt, size;
54 
55 	/*
56 	 * Normal users can read only the standardized portion of the
57 	 * configuration space as several chips lock up when trying to read
58 	 * undefined locations (think of Intel PIIX4 as a typical example).
59 	 */
60 
61 	if (capable(CAP_SYS_ADMIN))
62 		size = dp->size;
63 	else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
64 		size = 128;
65 	else
66 		size = 64;
67 
68 	if (pos >= size)
69 		return 0;
70 	if (nbytes >= size)
71 		nbytes = size;
72 	if (pos + nbytes > size)
73 		nbytes = size - pos;
74 	cnt = nbytes;
75 
76 	if (!access_ok(VERIFY_WRITE, buf, cnt))
77 		return -EINVAL;
78 
79 	if ((pos & 1) && cnt) {
80 		unsigned char val;
81 		pci_user_read_config_byte(dev, pos, &val);
82 		__put_user(val, buf);
83 		buf++;
84 		pos++;
85 		cnt--;
86 	}
87 
88 	if ((pos & 3) && cnt > 2) {
89 		unsigned short val;
90 		pci_user_read_config_word(dev, pos, &val);
91 		__put_user(cpu_to_le16(val), (__le16 __user *) buf);
92 		buf += 2;
93 		pos += 2;
94 		cnt -= 2;
95 	}
96 
97 	while (cnt >= 4) {
98 		unsigned int val;
99 		pci_user_read_config_dword(dev, pos, &val);
100 		__put_user(cpu_to_le32(val), (__le32 __user *) buf);
101 		buf += 4;
102 		pos += 4;
103 		cnt -= 4;
104 	}
105 
106 	if (cnt >= 2) {
107 		unsigned short val;
108 		pci_user_read_config_word(dev, pos, &val);
109 		__put_user(cpu_to_le16(val), (__le16 __user *) buf);
110 		buf += 2;
111 		pos += 2;
112 		cnt -= 2;
113 	}
114 
115 	if (cnt) {
116 		unsigned char val;
117 		pci_user_read_config_byte(dev, pos, &val);
118 		__put_user(val, buf);
119 		buf++;
120 		pos++;
121 		cnt--;
122 	}
123 
124 	*ppos = pos;
125 	return nbytes;
126 }
127 
128 static ssize_t
129 proc_bus_pci_write(struct file *file, const char __user *buf, size_t nbytes, loff_t *ppos)
130 {
131 	struct inode *ino = file->f_path.dentry->d_inode;
132 	const struct proc_dir_entry *dp = PDE(ino);
133 	struct pci_dev *dev = dp->data;
134 	int pos = *ppos;
135 	int size = dp->size;
136 	int cnt;
137 
138 	if (pos >= size)
139 		return 0;
140 	if (nbytes >= size)
141 		nbytes = size;
142 	if (pos + nbytes > size)
143 		nbytes = size - pos;
144 	cnt = nbytes;
145 
146 	if (!access_ok(VERIFY_READ, buf, cnt))
147 		return -EINVAL;
148 
149 	if ((pos & 1) && cnt) {
150 		unsigned char val;
151 		__get_user(val, buf);
152 		pci_user_write_config_byte(dev, pos, val);
153 		buf++;
154 		pos++;
155 		cnt--;
156 	}
157 
158 	if ((pos & 3) && cnt > 2) {
159 		__le16 val;
160 		__get_user(val, (__le16 __user *) buf);
161 		pci_user_write_config_word(dev, pos, le16_to_cpu(val));
162 		buf += 2;
163 		pos += 2;
164 		cnt -= 2;
165 	}
166 
167 	while (cnt >= 4) {
168 		__le32 val;
169 		__get_user(val, (__le32 __user *) buf);
170 		pci_user_write_config_dword(dev, pos, le32_to_cpu(val));
171 		buf += 4;
172 		pos += 4;
173 		cnt -= 4;
174 	}
175 
176 	if (cnt >= 2) {
177 		__le16 val;
178 		__get_user(val, (__le16 __user *) buf);
179 		pci_user_write_config_word(dev, pos, le16_to_cpu(val));
180 		buf += 2;
181 		pos += 2;
182 		cnt -= 2;
183 	}
184 
185 	if (cnt) {
186 		unsigned char val;
187 		__get_user(val, buf);
188 		pci_user_write_config_byte(dev, pos, val);
189 		buf++;
190 		pos++;
191 		cnt--;
192 	}
193 
194 	*ppos = pos;
195 	i_size_write(ino, dp->size);
196 	return nbytes;
197 }
198 
199 struct pci_filp_private {
200 	enum pci_mmap_state mmap_state;
201 	int write_combine;
202 };
203 
204 static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
205 			       unsigned long arg)
206 {
207 	const struct proc_dir_entry *dp = PDE(file->f_dentry->d_inode);
208 	struct pci_dev *dev = dp->data;
209 #ifdef HAVE_PCI_MMAP
210 	struct pci_filp_private *fpriv = file->private_data;
211 #endif /* HAVE_PCI_MMAP */
212 	int ret = 0;
213 
214 	lock_kernel();
215 
216 	switch (cmd) {
217 	case PCIIOC_CONTROLLER:
218 		ret = pci_domain_nr(dev->bus);
219 		break;
220 
221 #ifdef HAVE_PCI_MMAP
222 	case PCIIOC_MMAP_IS_IO:
223 		fpriv->mmap_state = pci_mmap_io;
224 		break;
225 
226 	case PCIIOC_MMAP_IS_MEM:
227 		fpriv->mmap_state = pci_mmap_mem;
228 		break;
229 
230 	case PCIIOC_WRITE_COMBINE:
231 		if (arg)
232 			fpriv->write_combine = 1;
233 		else
234 			fpriv->write_combine = 0;
235 		break;
236 
237 #endif /* HAVE_PCI_MMAP */
238 
239 	default:
240 		ret = -EINVAL;
241 		break;
242 	};
243 
244 	unlock_kernel();
245 	return ret;
246 }
247 
248 #ifdef HAVE_PCI_MMAP
249 static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
250 {
251 	struct inode *inode = file->f_path.dentry->d_inode;
252 	const struct proc_dir_entry *dp = PDE(inode);
253 	struct pci_dev *dev = dp->data;
254 	struct pci_filp_private *fpriv = file->private_data;
255 	int ret;
256 
257 	if (!capable(CAP_SYS_RAWIO))
258 		return -EPERM;
259 
260 	ret = pci_mmap_page_range(dev, vma,
261 				  fpriv->mmap_state,
262 				  fpriv->write_combine);
263 	if (ret < 0)
264 		return ret;
265 
266 	return 0;
267 }
268 
269 static int proc_bus_pci_open(struct inode *inode, struct file *file)
270 {
271 	struct pci_filp_private *fpriv = kmalloc(sizeof(*fpriv), GFP_KERNEL);
272 
273 	if (!fpriv)
274 		return -ENOMEM;
275 
276 	fpriv->mmap_state = pci_mmap_io;
277 	fpriv->write_combine = 0;
278 
279 	file->private_data = fpriv;
280 
281 	return 0;
282 }
283 
284 static int proc_bus_pci_release(struct inode *inode, struct file *file)
285 {
286 	kfree(file->private_data);
287 	file->private_data = NULL;
288 
289 	return 0;
290 }
291 #endif /* HAVE_PCI_MMAP */
292 
293 static const struct file_operations proc_bus_pci_operations = {
294 	.owner		= THIS_MODULE,
295 	.llseek		= proc_bus_pci_lseek,
296 	.read		= proc_bus_pci_read,
297 	.write		= proc_bus_pci_write,
298 	.unlocked_ioctl	= proc_bus_pci_ioctl,
299 #ifdef HAVE_PCI_MMAP
300 	.open		= proc_bus_pci_open,
301 	.release	= proc_bus_pci_release,
302 	.mmap		= proc_bus_pci_mmap,
303 #ifdef HAVE_ARCH_PCI_GET_UNMAPPED_AREA
304 	.get_unmapped_area = get_pci_unmapped_area,
305 #endif /* HAVE_ARCH_PCI_GET_UNMAPPED_AREA */
306 #endif /* HAVE_PCI_MMAP */
307 };
308 
309 /* iterator */
310 static void *pci_seq_start(struct seq_file *m, loff_t *pos)
311 {
312 	struct pci_dev *dev = NULL;
313 	loff_t n = *pos;
314 
315 	for_each_pci_dev(dev) {
316 		if (!n--)
317 			break;
318 	}
319 	return dev;
320 }
321 
322 static void *pci_seq_next(struct seq_file *m, void *v, loff_t *pos)
323 {
324 	struct pci_dev *dev = v;
325 
326 	(*pos)++;
327 	dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
328 	return dev;
329 }
330 
331 static void pci_seq_stop(struct seq_file *m, void *v)
332 {
333 	if (v) {
334 		struct pci_dev *dev = v;
335 		pci_dev_put(dev);
336 	}
337 }
338 
339 static int show_device(struct seq_file *m, void *v)
340 {
341 	const struct pci_dev *dev = v;
342 	const struct pci_driver *drv;
343 	int i;
344 
345 	if (dev == NULL)
346 		return 0;
347 
348 	drv = pci_dev_driver(dev);
349 	seq_printf(m, "%02x%02x\t%04x%04x\t%x",
350 			dev->bus->number,
351 			dev->devfn,
352 			dev->vendor,
353 			dev->device,
354 			dev->irq);
355 	/* Here should be 7 and not PCI_NUM_RESOURCES as we need to preserve compatibility */
356 	for (i=0; i<7; i++) {
357 		resource_size_t start, end;
358 		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
359 		seq_printf(m, "\t%16llx",
360 			(unsigned long long)(start |
361 			(dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
362 	}
363 	for (i=0; i<7; i++) {
364 		resource_size_t start, end;
365 		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
366 		seq_printf(m, "\t%16llx",
367 			dev->resource[i].start < dev->resource[i].end ?
368 			(unsigned long long)(end - start) + 1 : 0);
369 	}
370 	seq_putc(m, '\t');
371 	if (drv)
372 		seq_printf(m, "%s", drv->name);
373 	seq_putc(m, '\n');
374 	return 0;
375 }
376 
377 static const struct seq_operations proc_bus_pci_devices_op = {
378 	.start	= pci_seq_start,
379 	.next	= pci_seq_next,
380 	.stop	= pci_seq_stop,
381 	.show	= show_device
382 };
383 
384 static struct proc_dir_entry *proc_bus_pci_dir;
385 
386 int pci_proc_attach_device(struct pci_dev *dev)
387 {
388 	struct pci_bus *bus = dev->bus;
389 	struct proc_dir_entry *e;
390 	char name[16];
391 
392 	if (!proc_initialized)
393 		return -EACCES;
394 
395 	if (!bus->procdir) {
396 		if (pci_proc_domain(bus)) {
397 			sprintf(name, "%04x:%02x", pci_domain_nr(bus),
398 					bus->number);
399 		} else {
400 			sprintf(name, "%02x", bus->number);
401 		}
402 		bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
403 		if (!bus->procdir)
404 			return -ENOMEM;
405 	}
406 
407 	sprintf(name, "%02x.%x", PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
408 	e = proc_create_data(name, S_IFREG | S_IRUGO | S_IWUSR, bus->procdir,
409 			     &proc_bus_pci_operations, dev);
410 	if (!e)
411 		return -ENOMEM;
412 	e->size = dev->cfg_size;
413 	dev->procent = e;
414 
415 	return 0;
416 }
417 
418 int pci_proc_detach_device(struct pci_dev *dev)
419 {
420 	struct proc_dir_entry *e;
421 
422 	if ((e = dev->procent)) {
423 		if (atomic_read(&e->count) > 1)
424 			return -EBUSY;
425 		remove_proc_entry(e->name, dev->bus->procdir);
426 		dev->procent = NULL;
427 	}
428 	return 0;
429 }
430 
431 #if 0
432 int pci_proc_attach_bus(struct pci_bus* bus)
433 {
434 	struct proc_dir_entry *de = bus->procdir;
435 
436 	if (!proc_initialized)
437 		return -EACCES;
438 
439 	if (!de) {
440 		char name[16];
441 		sprintf(name, "%02x", bus->number);
442 		de = bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
443 		if (!de)
444 			return -ENOMEM;
445 	}
446 	return 0;
447 }
448 #endif  /*  0  */
449 
450 int pci_proc_detach_bus(struct pci_bus* bus)
451 {
452 	struct proc_dir_entry *de = bus->procdir;
453 	if (de)
454 		remove_proc_entry(de->name, proc_bus_pci_dir);
455 	return 0;
456 }
457 
458 static int proc_bus_pci_dev_open(struct inode *inode, struct file *file)
459 {
460 	return seq_open(file, &proc_bus_pci_devices_op);
461 }
462 static const struct file_operations proc_bus_pci_dev_operations = {
463 	.owner		= THIS_MODULE,
464 	.open		= proc_bus_pci_dev_open,
465 	.read		= seq_read,
466 	.llseek		= seq_lseek,
467 	.release	= seq_release,
468 };
469 
470 static int __init pci_proc_init(void)
471 {
472 	struct pci_dev *dev = NULL;
473 	proc_bus_pci_dir = proc_mkdir("bus/pci", NULL);
474 	proc_create("devices", 0, proc_bus_pci_dir,
475 		    &proc_bus_pci_dev_operations);
476 	proc_initialized = 1;
477 	while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
478 		pci_proc_attach_device(dev);
479 	}
480 	return 0;
481 }
482 
483 device_initcall(pci_proc_init);
484 
485