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/slab.h>
10 #include <linux/module.h>
11 #include <linux/proc_fs.h>
12 #include <linux/seq_file.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
proc_bus_pci_lseek(struct file * file,loff_t off,int whence)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
proc_bus_pci_read(struct file * file,char __user * buf,size_t nbytes,loff_t * ppos)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
proc_bus_pci_write(struct file * file,const char __user * buf,size_t nbytes,loff_t * ppos)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 
proc_bus_pci_ioctl(struct file * file,unsigned int cmd,unsigned long arg)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 	switch (cmd) {
215 	case PCIIOC_CONTROLLER:
216 		ret = pci_domain_nr(dev->bus);
217 		break;
218 
219 #ifdef HAVE_PCI_MMAP
220 	case PCIIOC_MMAP_IS_IO:
221 		fpriv->mmap_state = pci_mmap_io;
222 		break;
223 
224 	case PCIIOC_MMAP_IS_MEM:
225 		fpriv->mmap_state = pci_mmap_mem;
226 		break;
227 
228 	case PCIIOC_WRITE_COMBINE:
229 		if (arg)
230 			fpriv->write_combine = 1;
231 		else
232 			fpriv->write_combine = 0;
233 		break;
234 
235 #endif /* HAVE_PCI_MMAP */
236 
237 	default:
238 		ret = -EINVAL;
239 		break;
240 	};
241 
242 	return ret;
243 }
244 
245 #ifdef HAVE_PCI_MMAP
proc_bus_pci_mmap(struct file * file,struct vm_area_struct * vma)246 static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
247 {
248 	struct inode *inode = file->f_path.dentry->d_inode;
249 	const struct proc_dir_entry *dp = PDE(inode);
250 	struct pci_dev *dev = dp->data;
251 	struct pci_filp_private *fpriv = file->private_data;
252 	int i, ret;
253 
254 	if (!capable(CAP_SYS_RAWIO))
255 		return -EPERM;
256 
257 	/* Make sure the caller is mapping a real resource for this device */
258 	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
259 		if (pci_mmap_fits(dev, i, vma,  PCI_MMAP_PROCFS))
260 			break;
261 	}
262 
263 	if (i >= PCI_ROM_RESOURCE)
264 		return -ENODEV;
265 
266 	ret = pci_mmap_page_range(dev, vma,
267 				  fpriv->mmap_state,
268 				  fpriv->write_combine);
269 	if (ret < 0)
270 		return ret;
271 
272 	return 0;
273 }
274 
proc_bus_pci_open(struct inode * inode,struct file * file)275 static int proc_bus_pci_open(struct inode *inode, struct file *file)
276 {
277 	struct pci_filp_private *fpriv = kmalloc(sizeof(*fpriv), GFP_KERNEL);
278 
279 	if (!fpriv)
280 		return -ENOMEM;
281 
282 	fpriv->mmap_state = pci_mmap_io;
283 	fpriv->write_combine = 0;
284 
285 	file->private_data = fpriv;
286 
287 	return 0;
288 }
289 
proc_bus_pci_release(struct inode * inode,struct file * file)290 static int proc_bus_pci_release(struct inode *inode, struct file *file)
291 {
292 	kfree(file->private_data);
293 	file->private_data = NULL;
294 
295 	return 0;
296 }
297 #endif /* HAVE_PCI_MMAP */
298 
299 static const struct file_operations proc_bus_pci_operations = {
300 	.owner		= THIS_MODULE,
301 	.llseek		= proc_bus_pci_lseek,
302 	.read		= proc_bus_pci_read,
303 	.write		= proc_bus_pci_write,
304 	.unlocked_ioctl	= proc_bus_pci_ioctl,
305 	.compat_ioctl	= proc_bus_pci_ioctl,
306 #ifdef HAVE_PCI_MMAP
307 	.open		= proc_bus_pci_open,
308 	.release	= proc_bus_pci_release,
309 	.mmap		= proc_bus_pci_mmap,
310 #ifdef HAVE_ARCH_PCI_GET_UNMAPPED_AREA
311 	.get_unmapped_area = get_pci_unmapped_area,
312 #endif /* HAVE_ARCH_PCI_GET_UNMAPPED_AREA */
313 #endif /* HAVE_PCI_MMAP */
314 };
315 
316 /* iterator */
pci_seq_start(struct seq_file * m,loff_t * pos)317 static void *pci_seq_start(struct seq_file *m, loff_t *pos)
318 {
319 	struct pci_dev *dev = NULL;
320 	loff_t n = *pos;
321 
322 	for_each_pci_dev(dev) {
323 		if (!n--)
324 			break;
325 	}
326 	return dev;
327 }
328 
pci_seq_next(struct seq_file * m,void * v,loff_t * pos)329 static void *pci_seq_next(struct seq_file *m, void *v, loff_t *pos)
330 {
331 	struct pci_dev *dev = v;
332 
333 	(*pos)++;
334 	dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
335 	return dev;
336 }
337 
pci_seq_stop(struct seq_file * m,void * v)338 static void pci_seq_stop(struct seq_file *m, void *v)
339 {
340 	if (v) {
341 		struct pci_dev *dev = v;
342 		pci_dev_put(dev);
343 	}
344 }
345 
show_device(struct seq_file * m,void * v)346 static int show_device(struct seq_file *m, void *v)
347 {
348 	const struct pci_dev *dev = v;
349 	const struct pci_driver *drv;
350 	int i;
351 
352 	if (dev == NULL)
353 		return 0;
354 
355 	drv = pci_dev_driver(dev);
356 	seq_printf(m, "%02x%02x\t%04x%04x\t%x",
357 			dev->bus->number,
358 			dev->devfn,
359 			dev->vendor,
360 			dev->device,
361 			dev->irq);
362 
363 	/* only print standard and ROM resources to preserve compatibility */
364 	for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
365 		resource_size_t start, end;
366 		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
367 		seq_printf(m, "\t%16llx",
368 			(unsigned long long)(start |
369 			(dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
370 	}
371 	for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
372 		resource_size_t start, end;
373 		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
374 		seq_printf(m, "\t%16llx",
375 			dev->resource[i].start < dev->resource[i].end ?
376 			(unsigned long long)(end - start) + 1 : 0);
377 	}
378 	seq_putc(m, '\t');
379 	if (drv)
380 		seq_printf(m, "%s", drv->name);
381 	seq_putc(m, '\n');
382 	return 0;
383 }
384 
385 static const struct seq_operations proc_bus_pci_devices_op = {
386 	.start	= pci_seq_start,
387 	.next	= pci_seq_next,
388 	.stop	= pci_seq_stop,
389 	.show	= show_device
390 };
391 
392 static struct proc_dir_entry *proc_bus_pci_dir;
393 
pci_proc_attach_device(struct pci_dev * dev)394 int pci_proc_attach_device(struct pci_dev *dev)
395 {
396 	struct pci_bus *bus = dev->bus;
397 	struct proc_dir_entry *e;
398 	char name[16];
399 
400 	if (!proc_initialized)
401 		return -EACCES;
402 
403 	if (!bus->procdir) {
404 		if (pci_proc_domain(bus)) {
405 			sprintf(name, "%04x:%02x", pci_domain_nr(bus),
406 					bus->number);
407 		} else {
408 			sprintf(name, "%02x", bus->number);
409 		}
410 		bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
411 		if (!bus->procdir)
412 			return -ENOMEM;
413 	}
414 
415 	sprintf(name, "%02x.%x", PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
416 	e = proc_create_data(name, S_IFREG | S_IRUGO | S_IWUSR, bus->procdir,
417 			     &proc_bus_pci_operations, dev);
418 	if (!e)
419 		return -ENOMEM;
420 	e->size = dev->cfg_size;
421 	dev->procent = e;
422 
423 	return 0;
424 }
425 
pci_proc_detach_device(struct pci_dev * dev)426 int pci_proc_detach_device(struct pci_dev *dev)
427 {
428 	struct proc_dir_entry *e;
429 
430 	if ((e = dev->procent)) {
431 		remove_proc_entry(e->name, dev->bus->procdir);
432 		dev->procent = NULL;
433 	}
434 	return 0;
435 }
436 
437 #if 0
438 int pci_proc_attach_bus(struct pci_bus* bus)
439 {
440 	struct proc_dir_entry *de = bus->procdir;
441 
442 	if (!proc_initialized)
443 		return -EACCES;
444 
445 	if (!de) {
446 		char name[16];
447 		sprintf(name, "%02x", bus->number);
448 		de = bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
449 		if (!de)
450 			return -ENOMEM;
451 	}
452 	return 0;
453 }
454 #endif  /*  0  */
455 
pci_proc_detach_bus(struct pci_bus * bus)456 int pci_proc_detach_bus(struct pci_bus* bus)
457 {
458 	struct proc_dir_entry *de = bus->procdir;
459 	if (de)
460 		remove_proc_entry(de->name, proc_bus_pci_dir);
461 	return 0;
462 }
463 
proc_bus_pci_dev_open(struct inode * inode,struct file * file)464 static int proc_bus_pci_dev_open(struct inode *inode, struct file *file)
465 {
466 	return seq_open(file, &proc_bus_pci_devices_op);
467 }
468 static const struct file_operations proc_bus_pci_dev_operations = {
469 	.owner		= THIS_MODULE,
470 	.open		= proc_bus_pci_dev_open,
471 	.read		= seq_read,
472 	.llseek		= seq_lseek,
473 	.release	= seq_release,
474 };
475 
pci_proc_init(void)476 static int __init pci_proc_init(void)
477 {
478 	struct pci_dev *dev = NULL;
479 	proc_bus_pci_dir = proc_mkdir("bus/pci", NULL);
480 	proc_create("devices", 0, proc_bus_pci_dir,
481 		    &proc_bus_pci_dev_operations);
482 	proc_initialized = 1;
483 	for_each_pci_dev(dev)
484 		pci_proc_attach_device(dev);
485 
486 	return 0;
487 }
488 
489 device_initcall(pci_proc_init);
490 
491