FreeBSD/Linux Kernel Cross Reference
sys/kern/subr_rman.c
1 /*-
2 * Copyright 1998 Massachusetts Institute of Technology
3 *
4 * Permission to use, copy, modify, and distribute this software and
5 * its documentation for any purpose and without fee is hereby
6 * granted, provided that both the above copyright notice and this
7 * permission notice appear in all copies, that both the above
8 * copyright notice and this permission notice appear in all
9 * supporting documentation, and that the name of M.I.T. not be used
10 * in advertising or publicity pertaining to distribution of the
11 * software without specific, written prior permission. M.I.T. makes
12 * no representations about the suitability of this software for any
13 * purpose. It is provided "as is" without express or implied
14 * warranty.
15 *
16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 /*
31 * The kernel resource manager. This code is responsible for keeping track
32 * of hardware resources which are apportioned out to various drivers.
33 * It does not actually assign those resources, and it is not expected
34 * that end-device drivers will call into this code directly. Rather,
35 * the code which implements the buses that those devices are attached to,
36 * and the code which manages CPU resources, will call this code, and the
37 * end-device drivers will make upcalls to that code to actually perform
38 * the allocation.
39 *
40 * There are two sorts of resources managed by this code. The first is
41 * the more familiar array (RMAN_ARRAY) type; resources in this class
42 * consist of a sequence of individually-allocatable objects which have
43 * been numbered in some well-defined order. Most of the resources
44 * are of this type, as it is the most familiar. The second type is
45 * called a gauge (RMAN_GAUGE), and models fungible resources (i.e.,
46 * resources in which each instance is indistinguishable from every
47 * other instance). The principal anticipated application of gauges
48 * is in the context of power consumption, where a bus may have a specific
49 * power budget which all attached devices share. RMAN_GAUGE is not
50 * implemented yet.
51 *
52 * For array resources, we make one simplifying assumption: two clients
53 * sharing the same resource must use the same range of indices. That
54 * is to say, sharing of overlapping-but-not-identical regions is not
55 * permitted.
56 */
57
58 #include "opt_ddb.h"
59
60 #include <sys/cdefs.h>
61 __FBSDID("$FreeBSD$");
62
63 #include <sys/param.h>
64 #include <sys/systm.h>
65 #include <sys/kernel.h>
66 #include <sys/limits.h>
67 #include <sys/lock.h>
68 #include <sys/malloc.h>
69 #include <sys/mutex.h>
70 #include <sys/bus.h> /* XXX debugging */
71 #include <machine/bus.h>
72 #include <sys/rman.h>
73 #include <sys/sysctl.h>
74
75 #ifdef DDB
76 #include <ddb/ddb.h>
77 #endif
78
79 /*
80 * We use a linked list rather than a bitmap because we need to be able to
81 * represent potentially huge objects (like all of a processor's physical
82 * address space). That is also why the indices are defined to have type
83 * `unsigned long' -- that being the largest integral type in ISO C (1990).
84 * The 1999 version of C allows `long long'; we may need to switch to that
85 * at some point in the future, particularly if we want to support 36-bit
86 * addresses on IA32 hardware.
87 */
88 struct resource_i {
89 struct resource r_r;
90 TAILQ_ENTRY(resource_i) r_link;
91 LIST_ENTRY(resource_i) r_sharelink;
92 LIST_HEAD(, resource_i) *r_sharehead;
93 u_long r_start; /* index of the first entry in this resource */
94 u_long r_end; /* index of the last entry (inclusive) */
95 u_int r_flags;
96 void *r_virtual; /* virtual address of this resource */
97 struct device *r_dev; /* device which has allocated this resource */
98 struct rman *r_rm; /* resource manager from whence this came */
99 int r_rid; /* optional rid for this resource. */
100 };
101
102 static int rman_debug = 0;
103 TUNABLE_INT("debug.rman_debug", &rman_debug);
104 SYSCTL_INT(_debug, OID_AUTO, rman_debug, CTLFLAG_RW,
105 &rman_debug, 0, "rman debug");
106
107 #define DPRINTF(params) if (rman_debug) printf params
108
109 static MALLOC_DEFINE(M_RMAN, "rman", "Resource manager");
110
111 struct rman_head rman_head;
112 static struct mtx rman_mtx; /* mutex to protect rman_head */
113 static int int_rman_release_resource(struct rman *rm, struct resource_i *r);
114
115 static __inline struct resource_i *
116 int_alloc_resource(int malloc_flag)
117 {
118 struct resource_i *r;
119
120 r = malloc(sizeof *r, M_RMAN, malloc_flag | M_ZERO);
121 if (r != NULL) {
122 r->r_r.__r_i = r;
123 }
124 return (r);
125 }
126
127 int
128 rman_init(struct rman *rm)
129 {
130 static int once = 0;
131
132 if (once == 0) {
133 once = 1;
134 TAILQ_INIT(&rman_head);
135 mtx_init(&rman_mtx, "rman head", NULL, MTX_DEF);
136 }
137
138 if (rm->rm_start == 0 && rm->rm_end == 0)
139 rm->rm_end = ~0ul;
140 if (rm->rm_type == RMAN_UNINIT)
141 panic("rman_init");
142 if (rm->rm_type == RMAN_GAUGE)
143 panic("implement RMAN_GAUGE");
144
145 TAILQ_INIT(&rm->rm_list);
146 rm->rm_mtx = malloc(sizeof *rm->rm_mtx, M_RMAN, M_NOWAIT | M_ZERO);
147 if (rm->rm_mtx == NULL)
148 return ENOMEM;
149 mtx_init(rm->rm_mtx, "rman", NULL, MTX_DEF);
150
151 mtx_lock(&rman_mtx);
152 TAILQ_INSERT_TAIL(&rman_head, rm, rm_link);
153 mtx_unlock(&rman_mtx);
154 return 0;
155 }
156
157 int
158 rman_manage_region(struct rman *rm, u_long start, u_long end)
159 {
160 struct resource_i *r, *s, *t;
161
162 DPRINTF(("rman_manage_region: <%s> request: start %#lx, end %#lx\n",
163 rm->rm_descr, start, end));
164 if (start < rm->rm_start || end > rm->rm_end)
165 return EINVAL;
166 r = int_alloc_resource(M_NOWAIT);
167 if (r == NULL)
168 return ENOMEM;
169 r->r_start = start;
170 r->r_end = end;
171 r->r_rm = rm;
172
173 mtx_lock(rm->rm_mtx);
174
175 /* Skip entries before us. */
176 TAILQ_FOREACH(s, &rm->rm_list, r_link) {
177 if (s->r_end == ULONG_MAX)
178 break;
179 if (s->r_end + 1 >= r->r_start)
180 break;
181 }
182
183 /* If we ran off the end of the list, insert at the tail. */
184 if (s == NULL) {
185 TAILQ_INSERT_TAIL(&rm->rm_list, r, r_link);
186 } else {
187 /* Check for any overlap with the current region. */
188 if (r->r_start <= s->r_end && r->r_end >= s->r_start)
189 return EBUSY;
190
191 /* Check for any overlap with the next region. */
192 t = TAILQ_NEXT(s, r_link);
193 if (t && r->r_start <= t->r_end && r->r_end >= t->r_start)
194 return EBUSY;
195
196 /*
197 * See if this region can be merged with the next region. If
198 * not, clear the pointer.
199 */
200 if (t && (r->r_end + 1 != t->r_start || t->r_flags != 0))
201 t = NULL;
202
203 /* See if we can merge with the current region. */
204 if (s->r_end + 1 == r->r_start && s->r_flags == 0) {
205 /* Can we merge all 3 regions? */
206 if (t != NULL) {
207 s->r_end = t->r_end;
208 TAILQ_REMOVE(&rm->rm_list, t, r_link);
209 free(r, M_RMAN);
210 free(t, M_RMAN);
211 } else {
212 s->r_end = r->r_end;
213 free(r, M_RMAN);
214 }
215 } else if (t != NULL) {
216 /* Can we merge with just the next region? */
217 t->r_start = r->r_start;
218 free(r, M_RMAN);
219 } else if (s->r_end < r->r_start) {
220 TAILQ_INSERT_AFTER(&rm->rm_list, s, r, r_link);
221 } else {
222 TAILQ_INSERT_BEFORE(s, r, r_link);
223 }
224 }
225
226 mtx_unlock(rm->rm_mtx);
227 return 0;
228 }
229
230 int
231 rman_init_from_resource(struct rman *rm, struct resource *r)
232 {
233 int rv;
234
235 if ((rv = rman_init(rm)) != 0)
236 return (rv);
237 return (rman_manage_region(rm, r->__r_i->r_start, r->__r_i->r_end));
238 }
239
240 int
241 rman_fini(struct rman *rm)
242 {
243 struct resource_i *r;
244
245 mtx_lock(rm->rm_mtx);
246 TAILQ_FOREACH(r, &rm->rm_list, r_link) {
247 if (r->r_flags & RF_ALLOCATED) {
248 mtx_unlock(rm->rm_mtx);
249 return EBUSY;
250 }
251 }
252
253 /*
254 * There really should only be one of these if we are in this
255 * state and the code is working properly, but it can't hurt.
256 */
257 while (!TAILQ_EMPTY(&rm->rm_list)) {
258 r = TAILQ_FIRST(&rm->rm_list);
259 TAILQ_REMOVE(&rm->rm_list, r, r_link);
260 free(r, M_RMAN);
261 }
262 mtx_unlock(rm->rm_mtx);
263 mtx_lock(&rman_mtx);
264 TAILQ_REMOVE(&rman_head, rm, rm_link);
265 mtx_unlock(&rman_mtx);
266 mtx_destroy(rm->rm_mtx);
267 free(rm->rm_mtx, M_RMAN);
268
269 return 0;
270 }
271
272 int
273 rman_first_free_region(struct rman *rm, u_long *start, u_long *end)
274 {
275 struct resource_i *r;
276
277 mtx_lock(rm->rm_mtx);
278 TAILQ_FOREACH(r, &rm->rm_list, r_link) {
279 if (!(r->r_flags & RF_ALLOCATED)) {
280 *start = r->r_start;
281 *end = r->r_end;
282 mtx_unlock(rm->rm_mtx);
283 return (0);
284 }
285 }
286 mtx_unlock(rm->rm_mtx);
287 return (ENOENT);
288 }
289
290 int
291 rman_last_free_region(struct rman *rm, u_long *start, u_long *end)
292 {
293 struct resource_i *r;
294
295 mtx_lock(rm->rm_mtx);
296 TAILQ_FOREACH_REVERSE(r, &rm->rm_list, resource_head, r_link) {
297 if (!(r->r_flags & RF_ALLOCATED)) {
298 *start = r->r_start;
299 *end = r->r_end;
300 mtx_unlock(rm->rm_mtx);
301 return (0);
302 }
303 }
304 mtx_unlock(rm->rm_mtx);
305 return (ENOENT);
306 }
307
308 /* Shrink or extend one or both ends of an allocated resource. */
309 int
310 rman_adjust_resource(struct resource *rr, u_long start, u_long end)
311 {
312 struct resource_i *r, *s, *t, *new;
313 struct rman *rm;
314
315 /* Not supported for shared resources. */
316 r = rr->__r_i;
317 if (r->r_flags & RF_SHAREABLE)
318 return (EINVAL);
319
320 /*
321 * This does not support wholesale moving of a resource. At
322 * least part of the desired new range must overlap with the
323 * existing resource.
324 */
325 if (end < r->r_start || r->r_end < start)
326 return (EINVAL);
327
328 /*
329 * Find the two resource regions immediately adjacent to the
330 * allocated resource.
331 */
332 rm = r->r_rm;
333 mtx_lock(rm->rm_mtx);
334 #ifdef INVARIANTS
335 TAILQ_FOREACH(s, &rm->rm_list, r_link) {
336 if (s == r)
337 break;
338 }
339 if (s == NULL)
340 panic("resource not in list");
341 #endif
342 s = TAILQ_PREV(r, resource_head, r_link);
343 t = TAILQ_NEXT(r, r_link);
344 KASSERT(s == NULL || s->r_end + 1 == r->r_start,
345 ("prev resource mismatch"));
346 KASSERT(t == NULL || r->r_end + 1 == t->r_start,
347 ("next resource mismatch"));
348
349 /*
350 * See if the changes are permitted. Shrinking is always allowed,
351 * but growing requires sufficient room in the adjacent region.
352 */
353 if (start < r->r_start && (s == NULL || (s->r_flags & RF_ALLOCATED) ||
354 s->r_start > start)) {
355 mtx_unlock(rm->rm_mtx);
356 return (EBUSY);
357 }
358 if (end > r->r_end && (t == NULL || (t->r_flags & RF_ALLOCATED) ||
359 t->r_end < end)) {
360 mtx_unlock(rm->rm_mtx);
361 return (EBUSY);
362 }
363
364 /*
365 * While holding the lock, grow either end of the resource as
366 * needed and shrink either end if the shrinking does not require
367 * allocating a new resource. We can safely drop the lock and then
368 * insert a new range to handle the shrinking case afterwards.
369 */
370 if (start < r->r_start ||
371 (start > r->r_start && s != NULL && !(s->r_flags & RF_ALLOCATED))) {
372 KASSERT(s->r_flags == 0, ("prev is busy"));
373 r->r_start = start;
374 if (s->r_start == start) {
375 TAILQ_REMOVE(&rm->rm_list, s, r_link);
376 free(s, M_RMAN);
377 } else
378 s->r_end = start - 1;
379 }
380 if (end > r->r_end ||
381 (end < r->r_end && t != NULL && !(t->r_flags & RF_ALLOCATED))) {
382 KASSERT(t->r_flags == 0, ("next is busy"));
383 r->r_end = end;
384 if (t->r_end == end) {
385 TAILQ_REMOVE(&rm->rm_list, t, r_link);
386 free(t, M_RMAN);
387 } else
388 t->r_start = end + 1;
389 }
390 mtx_unlock(rm->rm_mtx);
391
392 /*
393 * Handle the shrinking cases that require allocating a new
394 * resource to hold the newly-free region. We have to recheck
395 * if we still need this new region after acquiring the lock.
396 */
397 if (start > r->r_start) {
398 new = int_alloc_resource(M_WAITOK);
399 new->r_start = r->r_start;
400 new->r_end = start - 1;
401 new->r_rm = rm;
402 mtx_lock(rm->rm_mtx);
403 r->r_start = start;
404 s = TAILQ_PREV(r, resource_head, r_link);
405 if (s != NULL && !(s->r_flags & RF_ALLOCATED)) {
406 s->r_end = start - 1;
407 free(new, M_RMAN);
408 } else
409 TAILQ_INSERT_BEFORE(r, new, r_link);
410 mtx_unlock(rm->rm_mtx);
411 }
412 if (end < r->r_end) {
413 new = int_alloc_resource(M_WAITOK);
414 new->r_start = end + 1;
415 new->r_end = r->r_end;
416 new->r_rm = rm;
417 mtx_lock(rm->rm_mtx);
418 r->r_end = end;
419 t = TAILQ_NEXT(r, r_link);
420 if (t != NULL && !(t->r_flags & RF_ALLOCATED)) {
421 t->r_start = end + 1;
422 free(new, M_RMAN);
423 } else
424 TAILQ_INSERT_AFTER(&rm->rm_list, r, new, r_link);
425 mtx_unlock(rm->rm_mtx);
426 }
427 return (0);
428 }
429
430 #define SHARE_TYPE(f) (f & (RF_SHAREABLE | RF_PREFETCHABLE))
431
432 struct resource *
433 rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
434 u_long count, u_long bound, u_int flags,
435 struct device *dev)
436 {
437 u_int new_rflags;
438 struct resource_i *r, *s, *rv;
439 u_long rstart, rend, amask, bmask;
440
441 rv = NULL;
442
443 DPRINTF(("rman_reserve_resource_bound: <%s> request: [%#lx, %#lx], "
444 "length %#lx, flags %u, device %s\n", rm->rm_descr, start, end,
445 count, flags,
446 dev == NULL ? "<null>" : device_get_nameunit(dev)));
447 KASSERT((flags & RF_FIRSTSHARE) == 0,
448 ("invalid flags %#x", flags));
449 new_rflags = (flags & ~RF_FIRSTSHARE) | RF_ALLOCATED;
450
451 mtx_lock(rm->rm_mtx);
452
453 for (r = TAILQ_FIRST(&rm->rm_list);
454 r && r->r_end < start + count - 1;
455 r = TAILQ_NEXT(r, r_link))
456 ;
457
458 if (r == NULL) {
459 DPRINTF(("could not find a region\n"));
460 goto out;
461 }
462
463 amask = (1ul << RF_ALIGNMENT(flags)) - 1;
464 KASSERT(start <= ULONG_MAX - amask,
465 ("start (%#lx) + amask (%#lx) would wrap around", start, amask));
466
467 /* If bound is 0, bmask will also be 0 */
468 bmask = ~(bound - 1);
469 /*
470 * First try to find an acceptable totally-unshared region.
471 */
472 for (s = r; s; s = TAILQ_NEXT(s, r_link)) {
473 DPRINTF(("considering [%#lx, %#lx]\n", s->r_start, s->r_end));
474 /*
475 * The resource list is sorted, so there is no point in
476 * searching further once r_start is too large.
477 */
478 if (s->r_start > end - (count - 1)) {
479 DPRINTF(("s->r_start (%#lx) + count - 1> end (%#lx)\n",
480 s->r_start, end));
481 break;
482 }
483 if (s->r_start > ULONG_MAX - amask) {
484 DPRINTF(("s->r_start (%#lx) + amask (%#lx) too large\n",
485 s->r_start, amask));
486 break;
487 }
488 if (s->r_flags & RF_ALLOCATED) {
489 DPRINTF(("region is allocated\n"));
490 continue;
491 }
492 rstart = ulmax(s->r_start, start);
493 /*
494 * Try to find a region by adjusting to boundary and alignment
495 * until both conditions are satisfied. This is not an optimal
496 * algorithm, but in most cases it isn't really bad, either.
497 */
498 do {
499 rstart = (rstart + amask) & ~amask;
500 if (((rstart ^ (rstart + count - 1)) & bmask) != 0)
501 rstart += bound - (rstart & ~bmask);
502 } while ((rstart & amask) != 0 && rstart < end &&
503 rstart < s->r_end);
504 rend = ulmin(s->r_end, ulmax(rstart + count - 1, end));
505 if (rstart > rend) {
506 DPRINTF(("adjusted start exceeds end\n"));
507 continue;
508 }
509 DPRINTF(("truncated region: [%#lx, %#lx]; size %#lx (requested %#lx)\n",
510 rstart, rend, (rend - rstart + 1), count));
511
512 if ((rend - rstart + 1) >= count) {
513 DPRINTF(("candidate region: [%#lx, %#lx], size %#lx\n",
514 rstart, rend, (rend - rstart + 1)));
515 if ((s->r_end - s->r_start + 1) == count) {
516 DPRINTF(("candidate region is entire chunk\n"));
517 rv = s;
518 rv->r_flags = new_rflags;
519 rv->r_dev = dev;
520 goto out;
521 }
522
523 /*
524 * If s->r_start < rstart and
525 * s->r_end > rstart + count - 1, then
526 * we need to split the region into three pieces
527 * (the middle one will get returned to the user).
528 * Otherwise, we are allocating at either the
529 * beginning or the end of s, so we only need to
530 * split it in two. The first case requires
531 * two new allocations; the second requires but one.
532 */
533 rv = int_alloc_resource(M_NOWAIT);
534 if (rv == NULL)
535 goto out;
536 rv->r_start = rstart;
537 rv->r_end = rstart + count - 1;
538 rv->r_flags = new_rflags;
539 rv->r_dev = dev;
540 rv->r_rm = rm;
541
542 if (s->r_start < rv->r_start && s->r_end > rv->r_end) {
543 DPRINTF(("splitting region in three parts: "
544 "[%#lx, %#lx]; [%#lx, %#lx]; [%#lx, %#lx]\n",
545 s->r_start, rv->r_start - 1,
546 rv->r_start, rv->r_end,
547 rv->r_end + 1, s->r_end));
548 /*
549 * We are allocating in the middle.
550 */
551 r = int_alloc_resource(M_NOWAIT);
552 if (r == NULL) {
553 free(rv, M_RMAN);
554 rv = NULL;
555 goto out;
556 }
557 r->r_start = rv->r_end + 1;
558 r->r_end = s->r_end;
559 r->r_flags = s->r_flags;
560 r->r_rm = rm;
561 s->r_end = rv->r_start - 1;
562 TAILQ_INSERT_AFTER(&rm->rm_list, s, rv,
563 r_link);
564 TAILQ_INSERT_AFTER(&rm->rm_list, rv, r,
565 r_link);
566 } else if (s->r_start == rv->r_start) {
567 DPRINTF(("allocating from the beginning\n"));
568 /*
569 * We are allocating at the beginning.
570 */
571 s->r_start = rv->r_end + 1;
572 TAILQ_INSERT_BEFORE(s, rv, r_link);
573 } else {
574 DPRINTF(("allocating at the end\n"));
575 /*
576 * We are allocating at the end.
577 */
578 s->r_end = rv->r_start - 1;
579 TAILQ_INSERT_AFTER(&rm->rm_list, s, rv,
580 r_link);
581 }
582 goto out;
583 }
584 }
585
586 /*
587 * Now find an acceptable shared region, if the client's requirements
588 * allow sharing. By our implementation restriction, a candidate
589 * region must match exactly by both size and sharing type in order
590 * to be considered compatible with the client's request. (The
591 * former restriction could probably be lifted without too much
592 * additional work, but this does not seem warranted.)
593 */
594 DPRINTF(("no unshared regions found\n"));
595 if ((flags & RF_SHAREABLE) == 0)
596 goto out;
597
598 for (s = r; s && s->r_end <= end; s = TAILQ_NEXT(s, r_link)) {
599 if (SHARE_TYPE(s->r_flags) == SHARE_TYPE(flags) &&
600 s->r_start >= start &&
601 (s->r_end - s->r_start + 1) == count &&
602 (s->r_start & amask) == 0 &&
603 ((s->r_start ^ s->r_end) & bmask) == 0) {
604 rv = int_alloc_resource(M_NOWAIT);
605 if (rv == NULL)
606 goto out;
607 rv->r_start = s->r_start;
608 rv->r_end = s->r_end;
609 rv->r_flags = new_rflags;
610 rv->r_dev = dev;
611 rv->r_rm = rm;
612 if (s->r_sharehead == NULL) {
613 s->r_sharehead = malloc(sizeof *s->r_sharehead,
614 M_RMAN, M_NOWAIT | M_ZERO);
615 if (s->r_sharehead == NULL) {
616 free(rv, M_RMAN);
617 rv = NULL;
618 goto out;
619 }
620 LIST_INIT(s->r_sharehead);
621 LIST_INSERT_HEAD(s->r_sharehead, s,
622 r_sharelink);
623 s->r_flags |= RF_FIRSTSHARE;
624 }
625 rv->r_sharehead = s->r_sharehead;
626 LIST_INSERT_HEAD(s->r_sharehead, rv, r_sharelink);
627 goto out;
628 }
629 }
630 /*
631 * We couldn't find anything.
632 */
633
634 out:
635 mtx_unlock(rm->rm_mtx);
636 return (rv == NULL ? NULL : &rv->r_r);
637 }
638
639 struct resource *
640 rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count,
641 u_int flags, struct device *dev)
642 {
643
644 return (rman_reserve_resource_bound(rm, start, end, count, 0, flags,
645 dev));
646 }
647
648 int
649 rman_activate_resource(struct resource *re)
650 {
651 struct resource_i *r;
652 struct rman *rm;
653
654 r = re->__r_i;
655 rm = r->r_rm;
656 mtx_lock(rm->rm_mtx);
657 r->r_flags |= RF_ACTIVE;
658 mtx_unlock(rm->rm_mtx);
659 return 0;
660 }
661
662 int
663 rman_deactivate_resource(struct resource *r)
664 {
665 struct rman *rm;
666
667 rm = r->__r_i->r_rm;
668 mtx_lock(rm->rm_mtx);
669 r->__r_i->r_flags &= ~RF_ACTIVE;
670 mtx_unlock(rm->rm_mtx);
671 return 0;
672 }
673
674 static int
675 int_rman_release_resource(struct rman *rm, struct resource_i *r)
676 {
677 struct resource_i *s, *t;
678
679 if (r->r_flags & RF_ACTIVE)
680 r->r_flags &= ~RF_ACTIVE;
681
682 /*
683 * Check for a sharing list first. If there is one, then we don't
684 * have to think as hard.
685 */
686 if (r->r_sharehead) {
687 /*
688 * If a sharing list exists, then we know there are at
689 * least two sharers.
690 *
691 * If we are in the main circleq, appoint someone else.
692 */
693 LIST_REMOVE(r, r_sharelink);
694 s = LIST_FIRST(r->r_sharehead);
695 if (r->r_flags & RF_FIRSTSHARE) {
696 s->r_flags |= RF_FIRSTSHARE;
697 TAILQ_INSERT_BEFORE(r, s, r_link);
698 TAILQ_REMOVE(&rm->rm_list, r, r_link);
699 }
700
701 /*
702 * Make sure that the sharing list goes away completely
703 * if the resource is no longer being shared at all.
704 */
705 if (LIST_NEXT(s, r_sharelink) == NULL) {
706 free(s->r_sharehead, M_RMAN);
707 s->r_sharehead = NULL;
708 s->r_flags &= ~RF_FIRSTSHARE;
709 }
710 goto out;
711 }
712
713 /*
714 * Look at the adjacent resources in the list and see if our
715 * segment can be merged with any of them. If either of the
716 * resources is allocated or is not exactly adjacent then they
717 * cannot be merged with our segment.
718 */
719 s = TAILQ_PREV(r, resource_head, r_link);
720 if (s != NULL && ((s->r_flags & RF_ALLOCATED) != 0 ||
721 s->r_end + 1 != r->r_start))
722 s = NULL;
723 t = TAILQ_NEXT(r, r_link);
724 if (t != NULL && ((t->r_flags & RF_ALLOCATED) != 0 ||
725 r->r_end + 1 != t->r_start))
726 t = NULL;
727
728 if (s != NULL && t != NULL) {
729 /*
730 * Merge all three segments.
731 */
732 s->r_end = t->r_end;
733 TAILQ_REMOVE(&rm->rm_list, r, r_link);
734 TAILQ_REMOVE(&rm->rm_list, t, r_link);
735 free(t, M_RMAN);
736 } else if (s != NULL) {
737 /*
738 * Merge previous segment with ours.
739 */
740 s->r_end = r->r_end;
741 TAILQ_REMOVE(&rm->rm_list, r, r_link);
742 } else if (t != NULL) {
743 /*
744 * Merge next segment with ours.
745 */
746 t->r_start = r->r_start;
747 TAILQ_REMOVE(&rm->rm_list, r, r_link);
748 } else {
749 /*
750 * At this point, we know there is nothing we
751 * can potentially merge with, because on each
752 * side, there is either nothing there or what is
753 * there is still allocated. In that case, we don't
754 * want to remove r from the list; we simply want to
755 * change it to an unallocated region and return
756 * without freeing anything.
757 */
758 r->r_flags &= ~RF_ALLOCATED;
759 r->r_dev = NULL;
760 return 0;
761 }
762
763 out:
764 free(r, M_RMAN);
765 return 0;
766 }
767
768 int
769 rman_release_resource(struct resource *re)
770 {
771 int rv;
772 struct resource_i *r;
773 struct rman *rm;
774
775 r = re->__r_i;
776 rm = r->r_rm;
777 mtx_lock(rm->rm_mtx);
778 rv = int_rman_release_resource(rm, r);
779 mtx_unlock(rm->rm_mtx);
780 return (rv);
781 }
782
783 uint32_t
784 rman_make_alignment_flags(uint32_t size)
785 {
786 int i;
787
788 /*
789 * Find the hightest bit set, and add one if more than one bit
790 * set. We're effectively computing the ceil(log2(size)) here.
791 */
792 for (i = 31; i > 0; i--)
793 if ((1 << i) & size)
794 break;
795 if (~(1 << i) & size)
796 i++;
797
798 return(RF_ALIGNMENT_LOG2(i));
799 }
800
801 void
802 rman_set_start(struct resource *r, u_long start)
803 {
804
805 r->__r_i->r_start = start;
806 }
807
808 u_long
809 rman_get_start(struct resource *r)
810 {
811
812 return (r->__r_i->r_start);
813 }
814
815 void
816 rman_set_end(struct resource *r, u_long end)
817 {
818
819 r->__r_i->r_end = end;
820 }
821
822 u_long
823 rman_get_end(struct resource *r)
824 {
825
826 return (r->__r_i->r_end);
827 }
828
829 u_long
830 rman_get_size(struct resource *r)
831 {
832
833 return (r->__r_i->r_end - r->__r_i->r_start + 1);
834 }
835
836 u_int
837 rman_get_flags(struct resource *r)
838 {
839
840 return (r->__r_i->r_flags);
841 }
842
843 void
844 rman_set_virtual(struct resource *r, void *v)
845 {
846
847 r->__r_i->r_virtual = v;
848 }
849
850 void *
851 rman_get_virtual(struct resource *r)
852 {
853
854 return (r->__r_i->r_virtual);
855 }
856
857 void
858 rman_set_bustag(struct resource *r, bus_space_tag_t t)
859 {
860
861 r->r_bustag = t;
862 }
863
864 bus_space_tag_t
865 rman_get_bustag(struct resource *r)
866 {
867
868 return (r->r_bustag);
869 }
870
871 void
872 rman_set_bushandle(struct resource *r, bus_space_handle_t h)
873 {
874
875 r->r_bushandle = h;
876 }
877
878 bus_space_handle_t
879 rman_get_bushandle(struct resource *r)
880 {
881
882 return (r->r_bushandle);
883 }
884
885 void
886 rman_set_rid(struct resource *r, int rid)
887 {
888
889 r->__r_i->r_rid = rid;
890 }
891
892 int
893 rman_get_rid(struct resource *r)
894 {
895
896 return (r->__r_i->r_rid);
897 }
898
899 void
900 rman_set_device(struct resource *r, struct device *dev)
901 {
902
903 r->__r_i->r_dev = dev;
904 }
905
906 struct device *
907 rman_get_device(struct resource *r)
908 {
909
910 return (r->__r_i->r_dev);
911 }
912
913 int
914 rman_is_region_manager(struct resource *r, struct rman *rm)
915 {
916
917 return (r->__r_i->r_rm == rm);
918 }
919
920 /*
921 * Sysctl interface for scanning the resource lists.
922 *
923 * We take two input parameters; the index into the list of resource
924 * managers, and the resource offset into the list.
925 */
926 static int
927 sysctl_rman(SYSCTL_HANDLER_ARGS)
928 {
929 int *name = (int *)arg1;
930 u_int namelen = arg2;
931 int rman_idx, res_idx;
932 struct rman *rm;
933 struct resource_i *res;
934 struct resource_i *sres;
935 struct u_rman urm;
936 struct u_resource ures;
937 int error;
938
939 if (namelen != 3)
940 return (EINVAL);
941
942 if (bus_data_generation_check(name[0]))
943 return (EINVAL);
944 rman_idx = name[1];
945 res_idx = name[2];
946
947 /*
948 * Find the indexed resource manager
949 */
950 mtx_lock(&rman_mtx);
951 TAILQ_FOREACH(rm, &rman_head, rm_link) {
952 if (rman_idx-- == 0)
953 break;
954 }
955 mtx_unlock(&rman_mtx);
956 if (rm == NULL)
957 return (ENOENT);
958
959 /*
960 * If the resource index is -1, we want details on the
961 * resource manager.
962 */
963 if (res_idx == -1) {
964 bzero(&urm, sizeof(urm));
965 urm.rm_handle = (uintptr_t)rm;
966 if (rm->rm_descr != NULL)
967 strlcpy(urm.rm_descr, rm->rm_descr, RM_TEXTLEN);
968 urm.rm_start = rm->rm_start;
969 urm.rm_size = rm->rm_end - rm->rm_start + 1;
970 urm.rm_type = rm->rm_type;
971
972 error = SYSCTL_OUT(req, &urm, sizeof(urm));
973 return (error);
974 }
975
976 /*
977 * Find the indexed resource and return it.
978 */
979 mtx_lock(rm->rm_mtx);
980 TAILQ_FOREACH(res, &rm->rm_list, r_link) {
981 if (res->r_sharehead != NULL) {
982 LIST_FOREACH(sres, res->r_sharehead, r_sharelink)
983 if (res_idx-- == 0) {
984 res = sres;
985 goto found;
986 }
987 }
988 else if (res_idx-- == 0)
989 goto found;
990 }
991 mtx_unlock(rm->rm_mtx);
992 return (ENOENT);
993
994 found:
995 bzero(&ures, sizeof(ures));
996 ures.r_handle = (uintptr_t)res;
997 ures.r_parent = (uintptr_t)res->r_rm;
998 ures.r_device = (uintptr_t)res->r_dev;
999 if (res->r_dev != NULL) {
1000 if (device_get_name(res->r_dev) != NULL) {
1001 snprintf(ures.r_devname, RM_TEXTLEN,
1002 "%s%d",
1003 device_get_name(res->r_dev),
1004 device_get_unit(res->r_dev));
1005 } else {
1006 strlcpy(ures.r_devname, "nomatch",
1007 RM_TEXTLEN);
1008 }
1009 } else {
1010 ures.r_devname[0] = '\0';
1011 }
1012 ures.r_start = res->r_start;
1013 ures.r_size = res->r_end - res->r_start + 1;
1014 ures.r_flags = res->r_flags;
1015
1016 mtx_unlock(rm->rm_mtx);
1017 error = SYSCTL_OUT(req, &ures, sizeof(ures));
1018 return (error);
1019 }
1020
1021 static SYSCTL_NODE(_hw_bus, OID_AUTO, rman, CTLFLAG_RD, sysctl_rman,
1022 "kernel resource manager");
1023
1024 #ifdef DDB
1025 static void
1026 dump_rman_header(struct rman *rm)
1027 {
1028
1029 if (db_pager_quit)
1030 return;
1031 db_printf("rman %p: %s (0x%lx-0x%lx full range)\n",
1032 rm, rm->rm_descr, rm->rm_start, rm->rm_end);
1033 }
1034
1035 static void
1036 dump_rman(struct rman *rm)
1037 {
1038 struct resource_i *r;
1039 const char *devname;
1040
1041 if (db_pager_quit)
1042 return;
1043 TAILQ_FOREACH(r, &rm->rm_list, r_link) {
1044 if (r->r_dev != NULL) {
1045 devname = device_get_nameunit(r->r_dev);
1046 if (devname == NULL)
1047 devname = "nomatch";
1048 } else
1049 devname = NULL;
1050 db_printf(" 0x%lx-0x%lx (RID=%d) ",
1051 r->r_start, r->r_end, r->r_rid);
1052 if (devname != NULL)
1053 db_printf("(%s)\n", devname);
1054 else
1055 db_printf("----\n");
1056 if (db_pager_quit)
1057 return;
1058 }
1059 }
1060
1061 DB_SHOW_COMMAND(rman, db_show_rman)
1062 {
1063
1064 if (have_addr) {
1065 dump_rman_header((struct rman *)addr);
1066 dump_rman((struct rman *)addr);
1067 }
1068 }
1069
1070 DB_SHOW_COMMAND(rmans, db_show_rmans)
1071 {
1072 struct rman *rm;
1073
1074 TAILQ_FOREACH(rm, &rman_head, rm_link) {
1075 dump_rman_header(rm);
1076 }
1077 }
1078
1079 DB_SHOW_ALL_COMMAND(rman, db_show_all_rman)
1080 {
1081 struct rman *rm;
1082
1083 TAILQ_FOREACH(rm, &rman_head, rm_link) {
1084 dump_rman_header(rm);
1085 dump_rman(rm);
1086 }
1087 }
1088 DB_SHOW_ALIAS(allrman, db_show_all_rman);
1089 #endif
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