xref: /freebsd/sys/dev/pci/pci_user.c (revision c68159a6d8eede11766cf13896d0f7670dbd51aa)
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/queue.h>
41 #include <sys/types.h>
42 
43 #include <vm/vm.h>
44 #include <vm/pmap.h>
45 #include <vm/vm_extern.h>
46 
47 #include <sys/bus.h>
48 #include <machine/bus.h>
49 #include <sys/rman.h>
50 #include <machine/resource.h>
51 
52 #include <sys/pciio.h>
53 #include <pci/pcireg.h>
54 #include <pci/pcivar.h>
55 
56 #include "pcib_if.h"
57 #include "pci_if.h"
58 
59 /*
60  * This is the user interface to PCI configuration space.
61  */
62 
63 static int	pci_open(dev_t dev, int oflags, int devtype, struct proc *p);
64 static int	pci_close(dev_t dev, int flag, int devtype, struct proc *p);
65 static int	pci_conf_match(struct pci_match_conf *matches, int num_matches,
66 			       struct pci_conf *match_buf);
67 static int	pci_ioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p);
68 
69 #define	PCI_CDEV	78
70 
71 struct cdevsw pcicdev = {
72 	/* open */	pci_open,
73 	/* close */	pci_close,
74 	/* read */	noread,
75 	/* write */	nowrite,
76 	/* ioctl */	pci_ioctl,
77 	/* poll */	nopoll,
78 	/* mmap */	nommap,
79 	/* strategy */	nostrategy,
80 	/* name */	"pci",
81 	/* maj */	PCI_CDEV,
82 	/* dump */	nodump,
83 	/* psize */	nopsize,
84 	/* flags */	0,
85 	/* bmaj */	-1
86 };
87 
88 static int
89 pci_open(dev_t dev, int oflags, int devtype, struct proc *p)
90 {
91 	if ((oflags & FWRITE) && securelevel > 0) {
92 		return EPERM;
93 	}
94 	return 0;
95 }
96 
97 static int
98 pci_close(dev_t dev, int flag, int devtype, struct proc *p)
99 {
100 	return 0;
101 }
102 
103 /*
104  * Match a single pci_conf structure against an array of pci_match_conf
105  * structures.  The first argument, 'matches', is an array of num_matches
106  * pci_match_conf structures.  match_buf is a pointer to the pci_conf
107  * structure that will be compared to every entry in the matches array.
108  * This function returns 1 on failure, 0 on success.
109  */
110 static int
111 pci_conf_match(struct pci_match_conf *matches, int num_matches,
112 	       struct pci_conf *match_buf)
113 {
114 	int i;
115 
116 	if ((matches == NULL) || (match_buf == NULL) || (num_matches <= 0))
117 		return(1);
118 
119 	for (i = 0; i < num_matches; i++) {
120 		/*
121 		 * I'm not sure why someone would do this...but...
122 		 */
123 		if (matches[i].flags == PCI_GETCONF_NO_MATCH)
124 			continue;
125 
126 		/*
127 		 * Look at each of the match flags.  If it's set, do the
128 		 * comparison.  If the comparison fails, we don't have a
129 		 * match, go on to the next item if there is one.
130 		 */
131 		if (((matches[i].flags & PCI_GETCONF_MATCH_BUS) != 0)
132 		 && (match_buf->pc_sel.pc_bus != matches[i].pc_sel.pc_bus))
133 			continue;
134 
135 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEV) != 0)
136 		 && (match_buf->pc_sel.pc_dev != matches[i].pc_sel.pc_dev))
137 			continue;
138 
139 		if (((matches[i].flags & PCI_GETCONF_MATCH_FUNC) != 0)
140 		 && (match_buf->pc_sel.pc_func != matches[i].pc_sel.pc_func))
141 			continue;
142 
143 		if (((matches[i].flags & PCI_GETCONF_MATCH_VENDOR) != 0)
144 		 && (match_buf->pc_vendor != matches[i].pc_vendor))
145 			continue;
146 
147 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEVICE) != 0)
148 		 && (match_buf->pc_device != matches[i].pc_device))
149 			continue;
150 
151 		if (((matches[i].flags & PCI_GETCONF_MATCH_CLASS) != 0)
152 		 && (match_buf->pc_class != matches[i].pc_class))
153 			continue;
154 
155 		if (((matches[i].flags & PCI_GETCONF_MATCH_UNIT) != 0)
156 		 && (match_buf->pd_unit != matches[i].pd_unit))
157 			continue;
158 
159 		if (((matches[i].flags & PCI_GETCONF_MATCH_NAME) != 0)
160 		 && (strncmp(matches[i].pd_name, match_buf->pd_name,
161 			     sizeof(match_buf->pd_name)) != 0))
162 			continue;
163 
164 		return(0);
165 	}
166 
167 	return(1);
168 }
169 
170 static int
171 pci_ioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
172 {
173 	device_t pci, pcib;
174 	struct pci_io *io;
175 	const char *name;
176 	int error;
177 
178 	if (!(flag & FWRITE))
179 		return EPERM;
180 
181 
182 	switch(cmd) {
183 	case PCIOCGETCONF:
184 		{
185 		struct pci_devinfo *dinfo;
186 		struct pci_conf_io *cio;
187 		struct devlist *devlist_head;
188 		struct pci_match_conf *pattern_buf;
189 		int num_patterns;
190 		size_t iolen;
191 		int ionum, i;
192 
193 		cio = (struct pci_conf_io *)data;
194 
195 		num_patterns = 0;
196 		dinfo = NULL;
197 
198 		/*
199 		 * Hopefully the user won't pass in a null pointer, but it
200 		 * can't hurt to check.
201 		 */
202 		if (cio == NULL) {
203 			error = EINVAL;
204 			break;
205 		}
206 
207 		/*
208 		 * If the user specified an offset into the device list,
209 		 * but the list has changed since they last called this
210 		 * ioctl, tell them that the list has changed.  They will
211 		 * have to get the list from the beginning.
212 		 */
213 		if ((cio->offset != 0)
214 		 && (cio->generation != pci_generation)){
215 			cio->num_matches = 0;
216 			cio->status = PCI_GETCONF_LIST_CHANGED;
217 			error = 0;
218 			break;
219 		}
220 
221 		/*
222 		 * Check to see whether the user has asked for an offset
223 		 * past the end of our list.
224 		 */
225 		if (cio->offset >= pci_numdevs) {
226 			cio->num_matches = 0;
227 			cio->status = PCI_GETCONF_LAST_DEVICE;
228 			error = 0;
229 			break;
230 		}
231 
232 		/* get the head of the device queue */
233 		devlist_head = &pci_devq;
234 
235 		/*
236 		 * Determine how much room we have for pci_conf structures.
237 		 * Round the user's buffer size down to the nearest
238 		 * multiple of sizeof(struct pci_conf) in case the user
239 		 * didn't specify a multiple of that size.
240 		 */
241 		iolen = min(cio->match_buf_len -
242 			    (cio->match_buf_len % sizeof(struct pci_conf)),
243 			    pci_numdevs * sizeof(struct pci_conf));
244 
245 		/*
246 		 * Since we know that iolen is a multiple of the size of
247 		 * the pciconf union, it's okay to do this.
248 		 */
249 		ionum = iolen / sizeof(struct pci_conf);
250 
251 		/*
252 		 * If this test is true, the user wants the pci_conf
253 		 * structures returned to match the supplied entries.
254 		 */
255 		if ((cio->num_patterns > 0)
256 		 && (cio->pat_buf_len > 0)) {
257 			/*
258 			 * pat_buf_len needs to be:
259 			 * num_patterns * sizeof(struct pci_match_conf)
260 			 * While it is certainly possible the user just
261 			 * allocated a large buffer, but set the number of
262 			 * matches correctly, it is far more likely that
263 			 * their kernel doesn't match the userland utility
264 			 * they're using.  It's also possible that the user
265 			 * forgot to initialize some variables.  Yes, this
266 			 * may be overly picky, but I hazard to guess that
267 			 * it's far more likely to just catch folks that
268 			 * updated their kernel but not their userland.
269 			 */
270 			if ((cio->num_patterns *
271 			    sizeof(struct pci_match_conf)) != cio->pat_buf_len){
272 				/* The user made a mistake, return an error*/
273 				cio->status = PCI_GETCONF_ERROR;
274 				printf("pci_ioctl: pat_buf_len %d != "
275 				       "num_patterns (%d) * sizeof(struct "
276 				       "pci_match_conf) (%d)\npci_ioctl: "
277 				       "pat_buf_len should be = %d\n",
278 				       cio->pat_buf_len, cio->num_patterns,
279 				       (int)sizeof(struct pci_match_conf),
280 				       (int)sizeof(struct pci_match_conf) *
281 				       cio->num_patterns);
282 				printf("pci_ioctl: do your headers match your "
283 				       "kernel?\n");
284 				cio->num_matches = 0;
285 				error = EINVAL;
286 				break;
287 			}
288 
289 			/*
290 			 * Check the user's buffer to make sure it's readable.
291 			 */
292 			if (!useracc((caddr_t)cio->patterns,
293 				    cio->pat_buf_len, VM_PROT_READ)) {
294 				printf("pci_ioctl: pattern buffer %p, "
295 				       "length %u isn't user accessible for"
296 				       " READ\n", cio->patterns,
297 				       cio->pat_buf_len);
298 				error = EACCES;
299 				break;
300 			}
301 			/*
302 			 * Allocate a buffer to hold the patterns.
303 			 */
304 			pattern_buf = malloc(cio->pat_buf_len, M_TEMP,
305 					     M_WAITOK);
306 			error = copyin(cio->patterns, pattern_buf,
307 				       cio->pat_buf_len);
308 			if (error != 0)
309 				break;
310 			num_patterns = cio->num_patterns;
311 
312 		} else if ((cio->num_patterns > 0)
313 			|| (cio->pat_buf_len > 0)) {
314 			/*
315 			 * The user made a mistake, spit out an error.
316 			 */
317 			cio->status = PCI_GETCONF_ERROR;
318 			cio->num_matches = 0;
319 			printf("pci_ioctl: invalid GETCONF arguments\n");
320 			error = EINVAL;
321 			break;
322 		} else
323 			pattern_buf = NULL;
324 
325 		/*
326 		 * Make sure we can write to the match buffer.
327 		 */
328 		if (!useracc((caddr_t)cio->matches,
329 			     cio->match_buf_len, VM_PROT_WRITE)) {
330 			printf("pci_ioctl: match buffer %p, length %u "
331 			       "isn't user accessible for WRITE\n",
332 			       cio->matches, cio->match_buf_len);
333 			error = EACCES;
334 			break;
335 		}
336 
337 		/*
338 		 * Go through the list of devices and copy out the devices
339 		 * that match the user's criteria.
340 		 */
341 		for (cio->num_matches = 0, error = 0, i = 0,
342 		     dinfo = STAILQ_FIRST(devlist_head);
343 		     (dinfo != NULL) && (cio->num_matches < ionum)
344 		     && (error == 0) && (i < pci_numdevs);
345 		     dinfo = STAILQ_NEXT(dinfo, pci_links), i++) {
346 
347 			if (i < cio->offset)
348 				continue;
349 
350 			/* Populate pd_name and pd_unit */
351 			name = NULL;
352 			if (dinfo->cfg.dev && dinfo->conf.pd_name[0] == '\0')
353 				name = device_get_name(dinfo->cfg.dev);
354 			if (name) {
355 				strncpy(dinfo->conf.pd_name, name,
356 					sizeof(dinfo->conf.pd_name));
357 				dinfo->conf.pd_name[PCI_MAXNAMELEN] = 0;
358 				dinfo->conf.pd_unit =
359 					device_get_unit(dinfo->cfg.dev);
360 			}
361 
362 			if ((pattern_buf == NULL) ||
363 			    (pci_conf_match(pattern_buf, num_patterns,
364 					    &dinfo->conf) == 0)) {
365 
366 				/*
367 				 * If we've filled up the user's buffer,
368 				 * break out at this point.  Since we've
369 				 * got a match here, we'll pick right back
370 				 * up at the matching entry.  We can also
371 				 * tell the user that there are more matches
372 				 * left.
373 				 */
374 				if (cio->num_matches >= ionum)
375 					break;
376 
377 				error = copyout(&dinfo->conf,
378 					        &cio->matches[cio->num_matches],
379 						sizeof(struct pci_conf));
380 				cio->num_matches++;
381 			}
382 		}
383 
384 		/*
385 		 * Set the pointer into the list, so if the user is getting
386 		 * n records at a time, where n < pci_numdevs,
387 		 */
388 		cio->offset = i;
389 
390 		/*
391 		 * Set the generation, the user will need this if they make
392 		 * another ioctl call with offset != 0.
393 		 */
394 		cio->generation = pci_generation;
395 
396 		/*
397 		 * If this is the last device, inform the user so he won't
398 		 * bother asking for more devices.  If dinfo isn't NULL, we
399 		 * know that there are more matches in the list because of
400 		 * the way the traversal is done.
401 		 */
402 		if (dinfo == NULL)
403 			cio->status = PCI_GETCONF_LAST_DEVICE;
404 		else
405 			cio->status = PCI_GETCONF_MORE_DEVS;
406 
407 		if (pattern_buf != NULL)
408 			free(pattern_buf, M_TEMP);
409 
410 		break;
411 		}
412 	case PCIOCREAD:
413 		io = (struct pci_io *)data;
414 		switch(io->pi_width) {
415 		case 4:
416 		case 2:
417 		case 1:
418 			/*
419 			 * Assume that the user-level bus number is
420 			 * actually the pciN instance number. We map
421 			 * from that to the real pcib+bus combination.
422 			 */
423 			pci = devclass_get_device(devclass_find("pci"),
424 						  io->pi_sel.pc_bus);
425 			if (pci) {
426 				int b = pcib_get_bus(pci);
427 				pcib = device_get_parent(pci);
428 				io->pi_data =
429 					PCIB_READ_CONFIG(pcib,
430 							 b,
431 							 io->pi_sel.pc_dev,
432 							 io->pi_sel.pc_func,
433 							 io->pi_reg,
434 							 io->pi_width);
435 				error = 0;
436 			} else {
437 				error = ENODEV;
438 			}
439 			break;
440 		default:
441 			error = ENODEV;
442 			break;
443 		}
444 		break;
445 
446 	case PCIOCWRITE:
447 		io = (struct pci_io *)data;
448 		switch(io->pi_width) {
449 		case 4:
450 		case 2:
451 		case 1:
452 			/*
453 			 * Assume that the user-level bus number is
454 			 * actually the pciN instance number. We map
455 			 * from that to the real pcib+bus combination.
456 			 */
457 			pci = devclass_get_device(devclass_find("pci"),
458 						  io->pi_sel.pc_bus);
459 			if (pci) {
460 				int b = pcib_get_bus(pci);
461 				pcib = device_get_parent(pci);
462 				PCIB_WRITE_CONFIG(pcib,
463 						  b,
464 						  io->pi_sel.pc_dev,
465 						  io->pi_sel.pc_func,
466 						  io->pi_reg,
467 						  io->pi_data,
468 						  io->pi_width);
469 				error = 0;
470 			} else {
471 				error = ENODEV;
472 			}
473 			break;
474 		default:
475 			error = ENODEV;
476 			break;
477 		}
478 		break;
479 
480 	default:
481 		error = ENOTTY;
482 		break;
483 	}
484 
485 	return (error);
486 }
487 
488