xref: /freebsd/sys/dev/pci/pci_user.c (revision 3ff369fed2a08f32dda232c10470b949bef9489f)
1 /*
2  * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  *
28  */
29 
30 #include "opt_bus.h"	/* XXX trim includes */
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/malloc.h>
35 #include <sys/module.h>
36 #include <sys/linker.h>
37 #include <sys/fcntl.h>
38 #include <sys/conf.h>
39 #include <sys/kernel.h>
40 #include <sys/proc.h>
41 #include <sys/queue.h>
42 #include <sys/types.h>
43 
44 #include <vm/vm.h>
45 #include <vm/pmap.h>
46 #include <vm/vm_extern.h>
47 
48 #include <sys/bus.h>
49 #include <machine/bus.h>
50 #include <sys/rman.h>
51 #include <machine/resource.h>
52 
53 #include <sys/pciio.h>
54 #include <pci/pcireg.h>
55 #include <pci/pcivar.h>
56 
57 #include "pcib_if.h"
58 #include "pci_if.h"
59 
60 /*
61  * This is the user interface to PCI configuration space.
62  */
63 
64 static d_open_t 	pci_open;
65 static d_close_t	pci_close;
66 static int	pci_conf_match(struct pci_match_conf *matches, int num_matches,
67 			       struct pci_conf *match_buf);
68 static d_ioctl_t	pci_ioctl;
69 
70 #define	PCI_CDEV	78
71 
72 struct cdevsw pcicdev = {
73 	/* open */	pci_open,
74 	/* close */	pci_close,
75 	/* read */	noread,
76 	/* write */	nowrite,
77 	/* ioctl */	pci_ioctl,
78 	/* poll */	nopoll,
79 	/* mmap */	nommap,
80 	/* strategy */	nostrategy,
81 	/* name */	"pci",
82 	/* maj */	PCI_CDEV,
83 	/* dump */	nodump,
84 	/* psize */	nopsize,
85 	/* flags */	0,
86 };
87 
88 static int
89 pci_open(dev_t dev, int oflags, int devtype, struct thread *td)
90 {
91 	int error;
92 
93 	if (oflags & FWRITE) {
94 		error = securelevel_gt(td->td_ucred, 0);
95 		if (error)
96 			return (error);
97 	}
98 
99 	return (0);
100 }
101 
102 static int
103 pci_close(dev_t dev, int flag, int devtype, struct thread *td)
104 {
105 	return 0;
106 }
107 
108 /*
109  * Match a single pci_conf structure against an array of pci_match_conf
110  * structures.  The first argument, 'matches', is an array of num_matches
111  * pci_match_conf structures.  match_buf is a pointer to the pci_conf
112  * structure that will be compared to every entry in the matches array.
113  * This function returns 1 on failure, 0 on success.
114  */
115 static int
116 pci_conf_match(struct pci_match_conf *matches, int num_matches,
117 	       struct pci_conf *match_buf)
118 {
119 	int i;
120 
121 	if ((matches == NULL) || (match_buf == NULL) || (num_matches <= 0))
122 		return(1);
123 
124 	for (i = 0; i < num_matches; i++) {
125 		/*
126 		 * I'm not sure why someone would do this...but...
127 		 */
128 		if (matches[i].flags == PCI_GETCONF_NO_MATCH)
129 			continue;
130 
131 		/*
132 		 * Look at each of the match flags.  If it's set, do the
133 		 * comparison.  If the comparison fails, we don't have a
134 		 * match, go on to the next item if there is one.
135 		 */
136 		if (((matches[i].flags & PCI_GETCONF_MATCH_BUS) != 0)
137 		 && (match_buf->pc_sel.pc_bus != matches[i].pc_sel.pc_bus))
138 			continue;
139 
140 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEV) != 0)
141 		 && (match_buf->pc_sel.pc_dev != matches[i].pc_sel.pc_dev))
142 			continue;
143 
144 		if (((matches[i].flags & PCI_GETCONF_MATCH_FUNC) != 0)
145 		 && (match_buf->pc_sel.pc_func != matches[i].pc_sel.pc_func))
146 			continue;
147 
148 		if (((matches[i].flags & PCI_GETCONF_MATCH_VENDOR) != 0)
149 		 && (match_buf->pc_vendor != matches[i].pc_vendor))
150 			continue;
151 
152 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEVICE) != 0)
153 		 && (match_buf->pc_device != matches[i].pc_device))
154 			continue;
155 
156 		if (((matches[i].flags & PCI_GETCONF_MATCH_CLASS) != 0)
157 		 && (match_buf->pc_class != matches[i].pc_class))
158 			continue;
159 
160 		if (((matches[i].flags & PCI_GETCONF_MATCH_UNIT) != 0)
161 		 && (match_buf->pd_unit != matches[i].pd_unit))
162 			continue;
163 
164 		if (((matches[i].flags & PCI_GETCONF_MATCH_NAME) != 0)
165 		 && (strncmp(matches[i].pd_name, match_buf->pd_name,
166 			     sizeof(match_buf->pd_name)) != 0))
167 			continue;
168 
169 		return(0);
170 	}
171 
172 	return(1);
173 }
174 
175 static int
176 pci_ioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct thread *td)
177 {
178 	device_t pci, pcib;
179 	struct pci_io *io;
180 	const char *name;
181 	int error;
182 
183 	if (!(flag & FWRITE))
184 		return EPERM;
185 
186 
187 	switch(cmd) {
188 	case PCIOCGETCONF:
189 		{
190 		struct pci_devinfo *dinfo;
191 		struct pci_conf_io *cio;
192 		struct devlist *devlist_head;
193 		struct pci_match_conf *pattern_buf;
194 		int num_patterns;
195 		size_t iolen;
196 		int ionum, i;
197 
198 		cio = (struct pci_conf_io *)data;
199 
200 		num_patterns = 0;
201 		dinfo = NULL;
202 
203 		/*
204 		 * Hopefully the user won't pass in a null pointer, but it
205 		 * can't hurt to check.
206 		 */
207 		if (cio == NULL) {
208 			error = EINVAL;
209 			break;
210 		}
211 
212 		/*
213 		 * If the user specified an offset into the device list,
214 		 * but the list has changed since they last called this
215 		 * ioctl, tell them that the list has changed.  They will
216 		 * have to get the list from the beginning.
217 		 */
218 		if ((cio->offset != 0)
219 		 && (cio->generation != pci_generation)){
220 			cio->num_matches = 0;
221 			cio->status = PCI_GETCONF_LIST_CHANGED;
222 			error = 0;
223 			break;
224 		}
225 
226 		/*
227 		 * Check to see whether the user has asked for an offset
228 		 * past the end of our list.
229 		 */
230 		if (cio->offset >= pci_numdevs) {
231 			cio->num_matches = 0;
232 			cio->status = PCI_GETCONF_LAST_DEVICE;
233 			error = 0;
234 			break;
235 		}
236 
237 		/* get the head of the device queue */
238 		devlist_head = &pci_devq;
239 
240 		/*
241 		 * Determine how much room we have for pci_conf structures.
242 		 * Round the user's buffer size down to the nearest
243 		 * multiple of sizeof(struct pci_conf) in case the user
244 		 * didn't specify a multiple of that size.
245 		 */
246 		iolen = min(cio->match_buf_len -
247 			    (cio->match_buf_len % sizeof(struct pci_conf)),
248 			    pci_numdevs * sizeof(struct pci_conf));
249 
250 		/*
251 		 * Since we know that iolen is a multiple of the size of
252 		 * the pciconf union, it's okay to do this.
253 		 */
254 		ionum = iolen / sizeof(struct pci_conf);
255 
256 		/*
257 		 * If this test is true, the user wants the pci_conf
258 		 * structures returned to match the supplied entries.
259 		 */
260 		if ((cio->num_patterns > 0)
261 		 && (cio->pat_buf_len > 0)) {
262 			/*
263 			 * pat_buf_len needs to be:
264 			 * num_patterns * sizeof(struct pci_match_conf)
265 			 * While it is certainly possible the user just
266 			 * allocated a large buffer, but set the number of
267 			 * matches correctly, it is far more likely that
268 			 * their kernel doesn't match the userland utility
269 			 * they're using.  It's also possible that the user
270 			 * forgot to initialize some variables.  Yes, this
271 			 * may be overly picky, but I hazard to guess that
272 			 * it's far more likely to just catch folks that
273 			 * updated their kernel but not their userland.
274 			 */
275 			if ((cio->num_patterns *
276 			    sizeof(struct pci_match_conf)) != cio->pat_buf_len){
277 				/* The user made a mistake, return an error*/
278 				cio->status = PCI_GETCONF_ERROR;
279 				printf("pci_ioctl: pat_buf_len %d != "
280 				       "num_patterns (%d) * sizeof(struct "
281 				       "pci_match_conf) (%d)\npci_ioctl: "
282 				       "pat_buf_len should be = %d\n",
283 				       cio->pat_buf_len, cio->num_patterns,
284 				       (int)sizeof(struct pci_match_conf),
285 				       (int)sizeof(struct pci_match_conf) *
286 				       cio->num_patterns);
287 				printf("pci_ioctl: do your headers match your "
288 				       "kernel?\n");
289 				cio->num_matches = 0;
290 				error = EINVAL;
291 				break;
292 			}
293 
294 			/*
295 			 * Check the user's buffer to make sure it's readable.
296 			 */
297 			if (!useracc((caddr_t)cio->patterns,
298 				    cio->pat_buf_len, VM_PROT_READ)) {
299 				printf("pci_ioctl: pattern buffer %p, "
300 				       "length %u isn't user accessible for"
301 				       " READ\n", cio->patterns,
302 				       cio->pat_buf_len);
303 				error = EACCES;
304 				break;
305 			}
306 			/*
307 			 * Allocate a buffer to hold the patterns.
308 			 */
309 			pattern_buf = malloc(cio->pat_buf_len, M_TEMP,
310 					     M_WAITOK);
311 			error = copyin(cio->patterns, pattern_buf,
312 				       cio->pat_buf_len);
313 			if (error != 0)
314 				break;
315 			num_patterns = cio->num_patterns;
316 
317 		} else if ((cio->num_patterns > 0)
318 			|| (cio->pat_buf_len > 0)) {
319 			/*
320 			 * The user made a mistake, spit out an error.
321 			 */
322 			cio->status = PCI_GETCONF_ERROR;
323 			cio->num_matches = 0;
324 			printf("pci_ioctl: invalid GETCONF arguments\n");
325 			error = EINVAL;
326 			break;
327 		} else
328 			pattern_buf = NULL;
329 
330 		/*
331 		 * Make sure we can write to the match buffer.
332 		 */
333 		if (!useracc((caddr_t)cio->matches,
334 			     cio->match_buf_len, VM_PROT_WRITE)) {
335 			printf("pci_ioctl: match buffer %p, length %u "
336 			       "isn't user accessible for WRITE\n",
337 			       cio->matches, cio->match_buf_len);
338 			error = EACCES;
339 			break;
340 		}
341 
342 		/*
343 		 * Go through the list of devices and copy out the devices
344 		 * that match the user's criteria.
345 		 */
346 		for (cio->num_matches = 0, error = 0, i = 0,
347 		     dinfo = STAILQ_FIRST(devlist_head);
348 		     (dinfo != NULL) && (cio->num_matches < ionum)
349 		     && (error == 0) && (i < pci_numdevs);
350 		     dinfo = STAILQ_NEXT(dinfo, pci_links), i++) {
351 
352 			if (i < cio->offset)
353 				continue;
354 
355 			/* Populate pd_name and pd_unit */
356 			name = NULL;
357 			if (dinfo->cfg.dev && dinfo->conf.pd_name[0] == '\0')
358 				name = device_get_name(dinfo->cfg.dev);
359 			if (name) {
360 				strncpy(dinfo->conf.pd_name, name,
361 					sizeof(dinfo->conf.pd_name));
362 				dinfo->conf.pd_name[PCI_MAXNAMELEN] = 0;
363 				dinfo->conf.pd_unit =
364 					device_get_unit(dinfo->cfg.dev);
365 			}
366 
367 			if ((pattern_buf == NULL) ||
368 			    (pci_conf_match(pattern_buf, num_patterns,
369 					    &dinfo->conf) == 0)) {
370 
371 				/*
372 				 * If we've filled up the user's buffer,
373 				 * break out at this point.  Since we've
374 				 * got a match here, we'll pick right back
375 				 * up at the matching entry.  We can also
376 				 * tell the user that there are more matches
377 				 * left.
378 				 */
379 				if (cio->num_matches >= ionum)
380 					break;
381 
382 				error = copyout(&dinfo->conf,
383 					        &cio->matches[cio->num_matches],
384 						sizeof(struct pci_conf));
385 				cio->num_matches++;
386 			}
387 		}
388 
389 		/*
390 		 * Set the pointer into the list, so if the user is getting
391 		 * n records at a time, where n < pci_numdevs,
392 		 */
393 		cio->offset = i;
394 
395 		/*
396 		 * Set the generation, the user will need this if they make
397 		 * another ioctl call with offset != 0.
398 		 */
399 		cio->generation = pci_generation;
400 
401 		/*
402 		 * If this is the last device, inform the user so he won't
403 		 * bother asking for more devices.  If dinfo isn't NULL, we
404 		 * know that there are more matches in the list because of
405 		 * the way the traversal is done.
406 		 */
407 		if (dinfo == NULL)
408 			cio->status = PCI_GETCONF_LAST_DEVICE;
409 		else
410 			cio->status = PCI_GETCONF_MORE_DEVS;
411 
412 		if (pattern_buf != NULL)
413 			free(pattern_buf, M_TEMP);
414 
415 		break;
416 		}
417 	case PCIOCREAD:
418 		io = (struct pci_io *)data;
419 		switch(io->pi_width) {
420 		case 4:
421 		case 2:
422 		case 1:
423 			/*
424 			 * Assume that the user-level bus number is
425 			 * actually the pciN instance number. We map
426 			 * from that to the real pcib+bus combination.
427 			 */
428 			pci = devclass_get_device(devclass_find("pci"),
429 						  io->pi_sel.pc_bus);
430 			if (pci) {
431 				int b = pcib_get_bus(pci);
432 				pcib = device_get_parent(pci);
433 				io->pi_data =
434 					PCIB_READ_CONFIG(pcib,
435 							 b,
436 							 io->pi_sel.pc_dev,
437 							 io->pi_sel.pc_func,
438 							 io->pi_reg,
439 							 io->pi_width);
440 				error = 0;
441 			} else {
442 				error = ENODEV;
443 			}
444 			break;
445 		default:
446 			error = ENODEV;
447 			break;
448 		}
449 		break;
450 
451 	case PCIOCWRITE:
452 		io = (struct pci_io *)data;
453 		switch(io->pi_width) {
454 		case 4:
455 		case 2:
456 		case 1:
457 			/*
458 			 * Assume that the user-level bus number is
459 			 * actually the pciN instance number. We map
460 			 * from that to the real pcib+bus combination.
461 			 */
462 			pci = devclass_get_device(devclass_find("pci"),
463 						  io->pi_sel.pc_bus);
464 			if (pci) {
465 				int b = pcib_get_bus(pci);
466 				pcib = device_get_parent(pci);
467 				PCIB_WRITE_CONFIG(pcib,
468 						  b,
469 						  io->pi_sel.pc_dev,
470 						  io->pi_sel.pc_func,
471 						  io->pi_reg,
472 						  io->pi_data,
473 						  io->pi_width);
474 				error = 0;
475 			} else {
476 				error = ENODEV;
477 			}
478 			break;
479 		default:
480 			error = ENODEV;
481 			break;
482 		}
483 		break;
484 
485 	default:
486 		error = ENOTTY;
487 		break;
488 	}
489 
490 	return (error);
491 }
492 
493