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: releng/10.4/sys/kern/subr_rman.c 292417 2015-12-18 00:40:19Z jhb $");
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 int rv = 0;
162
163 DPRINTF(("rman_manage_region: <%s> request: start %#lx, end %#lx\n",
164 rm->rm_descr, start, end));
165 if (start < rm->rm_start || end > rm->rm_end)
166 return EINVAL;
167 r = int_alloc_resource(M_NOWAIT);
168 if (r == NULL)
169 return ENOMEM;
170 r->r_start = start;
171 r->r_end = end;
172 r->r_rm = rm;
173
174 mtx_lock(rm->rm_mtx);
175
176 /* Skip entries before us. */
177 TAILQ_FOREACH(s, &rm->rm_list, r_link) {
178 if (s->r_end == ULONG_MAX)
179 break;
180 if (s->r_end + 1 >= r->r_start)
181 break;
182 }
183
184 /* If we ran off the end of the list, insert at the tail. */
185 if (s == NULL) {
186 TAILQ_INSERT_TAIL(&rm->rm_list, r, r_link);
187 } else {
188 /* Check for any overlap with the current region. */
189 if (r->r_start <= s->r_end && r->r_end >= s->r_start) {
190 rv = EBUSY;
191 goto out;
192 }
193
194 /* Check for any overlap with the next region. */
195 t = TAILQ_NEXT(s, r_link);
196 if (t && r->r_start <= t->r_end && r->r_end >= t->r_start) {
197 rv = EBUSY;
198 goto out;
199 }
200
201 /*
202 * See if this region can be merged with the next region. If
203 * not, clear the pointer.
204 */
205 if (t && (r->r_end + 1 != t->r_start || t->r_flags != 0))
206 t = NULL;
207
208 /* See if we can merge with the current region. */
209 if (s->r_end + 1 == r->r_start && s->r_flags == 0) {
210 /* Can we merge all 3 regions? */
211 if (t != NULL) {
212 s->r_end = t->r_end;
213 TAILQ_REMOVE(&rm->rm_list, t, r_link);
214 free(r, M_RMAN);
215 free(t, M_RMAN);
216 } else {
217 s->r_end = r->r_end;
218 free(r, M_RMAN);
219 }
220 } else if (t != NULL) {
221 /* Can we merge with just the next region? */
222 t->r_start = r->r_start;
223 free(r, M_RMAN);
224 } else if (s->r_end < r->r_start) {
225 TAILQ_INSERT_AFTER(&rm->rm_list, s, r, r_link);
226 } else {
227 TAILQ_INSERT_BEFORE(s, r, r_link);
228 }
229 }
230 out:
231 mtx_unlock(rm->rm_mtx);
232 return rv;
233 }
234
235 int
236 rman_init_from_resource(struct rman *rm, struct resource *r)
237 {
238 int rv;
239
240 if ((rv = rman_init(rm)) != 0)
241 return (rv);
242 return (rman_manage_region(rm, r->__r_i->r_start, r->__r_i->r_end));
243 }
244
245 int
246 rman_fini(struct rman *rm)
247 {
248 struct resource_i *r;
249
250 mtx_lock(rm->rm_mtx);
251 TAILQ_FOREACH(r, &rm->rm_list, r_link) {
252 if (r->r_flags & RF_ALLOCATED) {
253 mtx_unlock(rm->rm_mtx);
254 return EBUSY;
255 }
256 }
257
258 /*
259 * There really should only be one of these if we are in this
260 * state and the code is working properly, but it can't hurt.
261 */
262 while (!TAILQ_EMPTY(&rm->rm_list)) {
263 r = TAILQ_FIRST(&rm->rm_list);
264 TAILQ_REMOVE(&rm->rm_list, r, r_link);
265 free(r, M_RMAN);
266 }
267 mtx_unlock(rm->rm_mtx);
268 mtx_lock(&rman_mtx);
269 TAILQ_REMOVE(&rman_head, rm, rm_link);
270 mtx_unlock(&rman_mtx);
271 mtx_destroy(rm->rm_mtx);
272 free(rm->rm_mtx, M_RMAN);
273
274 return 0;
275 }
276
277 int
278 rman_first_free_region(struct rman *rm, u_long *start, u_long *end)
279 {
280 struct resource_i *r;
281
282 mtx_lock(rm->rm_mtx);
283 TAILQ_FOREACH(r, &rm->rm_list, r_link) {
284 if (!(r->r_flags & RF_ALLOCATED)) {
285 *start = r->r_start;
286 *end = r->r_end;
287 mtx_unlock(rm->rm_mtx);
288 return (0);
289 }
290 }
291 mtx_unlock(rm->rm_mtx);
292 return (ENOENT);
293 }
294
295 int
296 rman_last_free_region(struct rman *rm, u_long *start, u_long *end)
297 {
298 struct resource_i *r;
299
300 mtx_lock(rm->rm_mtx);
301 TAILQ_FOREACH_REVERSE(r, &rm->rm_list, resource_head, r_link) {
302 if (!(r->r_flags & RF_ALLOCATED)) {
303 *start = r->r_start;
304 *end = r->r_end;
305 mtx_unlock(rm->rm_mtx);
306 return (0);
307 }
308 }
309 mtx_unlock(rm->rm_mtx);
310 return (ENOENT);
311 }
312
313 /* Shrink or extend one or both ends of an allocated resource. */
314 int
315 rman_adjust_resource(struct resource *rr, u_long start, u_long end)
316 {
317 struct resource_i *r, *s, *t, *new;
318 struct rman *rm;
319
320 /* Not supported for shared resources. */
321 r = rr->__r_i;
322 if (r->r_flags & RF_SHAREABLE)
323 return (EINVAL);
324
325 /*
326 * This does not support wholesale moving of a resource. At
327 * least part of the desired new range must overlap with the
328 * existing resource.
329 */
330 if (end < r->r_start || r->r_end < start)
331 return (EINVAL);
332
333 /*
334 * Find the two resource regions immediately adjacent to the
335 * allocated resource.
336 */
337 rm = r->r_rm;
338 mtx_lock(rm->rm_mtx);
339 #ifdef INVARIANTS
340 TAILQ_FOREACH(s, &rm->rm_list, r_link) {
341 if (s == r)
342 break;
343 }
344 if (s == NULL)
345 panic("resource not in list");
346 #endif
347 s = TAILQ_PREV(r, resource_head, r_link);
348 t = TAILQ_NEXT(r, r_link);
349 KASSERT(s == NULL || s->r_end + 1 == r->r_start,
350 ("prev resource mismatch"));
351 KASSERT(t == NULL || r->r_end + 1 == t->r_start,
352 ("next resource mismatch"));
353
354 /*
355 * See if the changes are permitted. Shrinking is always allowed,
356 * but growing requires sufficient room in the adjacent region.
357 */
358 if (start < r->r_start && (s == NULL || (s->r_flags & RF_ALLOCATED) ||
359 s->r_start > start)) {
360 mtx_unlock(rm->rm_mtx);
361 return (EBUSY);
362 }
363 if (end > r->r_end && (t == NULL || (t->r_flags & RF_ALLOCATED) ||
364 t->r_end < end)) {
365 mtx_unlock(rm->rm_mtx);
366 return (EBUSY);
367 }
368
369 /*
370 * While holding the lock, grow either end of the resource as
371 * needed and shrink either end if the shrinking does not require
372 * allocating a new resource. We can safely drop the lock and then
373 * insert a new range to handle the shrinking case afterwards.
374 */
375 if (start < r->r_start ||
376 (start > r->r_start && s != NULL && !(s->r_flags & RF_ALLOCATED))) {
377 KASSERT(s->r_flags == 0, ("prev is busy"));
378 r->r_start = start;
379 if (s->r_start == start) {
380 TAILQ_REMOVE(&rm->rm_list, s, r_link);
381 free(s, M_RMAN);
382 } else
383 s->r_end = start - 1;
384 }
385 if (end > r->r_end ||
386 (end < r->r_end && t != NULL && !(t->r_flags & RF_ALLOCATED))) {
387 KASSERT(t->r_flags == 0, ("next is busy"));
388 r->r_end = end;
389 if (t->r_end == end) {
390 TAILQ_REMOVE(&rm->rm_list, t, r_link);
391 free(t, M_RMAN);
392 } else
393 t->r_start = end + 1;
394 }
395 mtx_unlock(rm->rm_mtx);
396
397 /*
398 * Handle the shrinking cases that require allocating a new
399 * resource to hold the newly-free region. We have to recheck
400 * if we still need this new region after acquiring the lock.
401 */
402 if (start > r->r_start) {
403 new = int_alloc_resource(M_WAITOK);
404 new->r_start = r->r_start;
405 new->r_end = start - 1;
406 new->r_rm = rm;
407 mtx_lock(rm->rm_mtx);
408 r->r_start = start;
409 s = TAILQ_PREV(r, resource_head, r_link);
410 if (s != NULL && !(s->r_flags & RF_ALLOCATED)) {
411 s->r_end = start - 1;
412 free(new, M_RMAN);
413 } else
414 TAILQ_INSERT_BEFORE(r, new, r_link);
415 mtx_unlock(rm->rm_mtx);
416 }
417 if (end < r->r_end) {
418 new = int_alloc_resource(M_WAITOK);
419 new->r_start = end + 1;
420 new->r_end = r->r_end;
421 new->r_rm = rm;
422 mtx_lock(rm->rm_mtx);
423 r->r_end = end;
424 t = TAILQ_NEXT(r, r_link);
425 if (t != NULL && !(t->r_flags & RF_ALLOCATED)) {
426 t->r_start = end + 1;
427 free(new, M_RMAN);
428 } else
429 TAILQ_INSERT_AFTER(&rm->rm_list, r, new, r_link);
430 mtx_unlock(rm->rm_mtx);
431 }
432 return (0);
433 }
434
435 #define SHARE_TYPE(f) (f & (RF_SHAREABLE | RF_PREFETCHABLE))
436
437 struct resource *
438 rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
439 u_long count, u_long bound, u_int flags,
440 struct device *dev)
441 {
442 u_int new_rflags;
443 struct resource_i *r, *s, *rv;
444 u_long rstart, rend, amask, bmask;
445
446 rv = NULL;
447
448 DPRINTF(("rman_reserve_resource_bound: <%s> request: [%#lx, %#lx], "
449 "length %#lx, flags %u, device %s\n", rm->rm_descr, start, end,
450 count, flags,
451 dev == NULL ? "<null>" : device_get_nameunit(dev)));
452 KASSERT((flags & RF_FIRSTSHARE) == 0,
453 ("invalid flags %#x", flags));
454 new_rflags = (flags & ~RF_FIRSTSHARE) | RF_ALLOCATED;
455
456 mtx_lock(rm->rm_mtx);
457
458 for (r = TAILQ_FIRST(&rm->rm_list);
459 r && r->r_end < start + count - 1;
460 r = TAILQ_NEXT(r, r_link))
461 ;
462
463 if (r == NULL) {
464 DPRINTF(("could not find a region\n"));
465 goto out;
466 }
467
468 amask = (1ul << RF_ALIGNMENT(flags)) - 1;
469 KASSERT(start <= ULONG_MAX - amask,
470 ("start (%#lx) + amask (%#lx) would wrap around", start, amask));
471
472 /* If bound is 0, bmask will also be 0 */
473 bmask = ~(bound - 1);
474 /*
475 * First try to find an acceptable totally-unshared region.
476 */
477 for (s = r; s; s = TAILQ_NEXT(s, r_link)) {
478 DPRINTF(("considering [%#lx, %#lx]\n", s->r_start, s->r_end));
479 /*
480 * The resource list is sorted, so there is no point in
481 * searching further once r_start is too large.
482 */
483 if (s->r_start > end - (count - 1)) {
484 DPRINTF(("s->r_start (%#lx) + count - 1> end (%#lx)\n",
485 s->r_start, end));
486 break;
487 }
488 if (s->r_start > ULONG_MAX - amask) {
489 DPRINTF(("s->r_start (%#lx) + amask (%#lx) too large\n",
490 s->r_start, amask));
491 break;
492 }
493 if (s->r_flags & RF_ALLOCATED) {
494 DPRINTF(("region is allocated\n"));
495 continue;
496 }
497 rstart = ulmax(s->r_start, start);
498 /*
499 * Try to find a region by adjusting to boundary and alignment
500 * until both conditions are satisfied. This is not an optimal
501 * algorithm, but in most cases it isn't really bad, either.
502 */
503 do {
504 rstart = (rstart + amask) & ~amask;
505 if (((rstart ^ (rstart + count - 1)) & bmask) != 0)
506 rstart += bound - (rstart & ~bmask);
507 } while ((rstart & amask) != 0 && rstart < end &&
508 rstart < s->r_end);
509 rend = ulmin(s->r_end, ulmax(rstart + count - 1, end));
510 if (rstart > rend) {
511 DPRINTF(("adjusted start exceeds end\n"));
512 continue;
513 }
514 DPRINTF(("truncated region: [%#lx, %#lx]; size %#lx (requested %#lx)\n",
515 rstart, rend, (rend - rstart + 1), count));
516
517 if ((rend - rstart + 1) >= count) {
518 DPRINTF(("candidate region: [%#lx, %#lx], size %#lx\n",
519 rstart, rend, (rend - rstart + 1)));
520 if ((s->r_end - s->r_start + 1) == count) {
521 DPRINTF(("candidate region is entire chunk\n"));
522 rv = s;
523 rv->r_flags = new_rflags;
524 rv->r_dev = dev;
525 goto out;
526 }
527
528 /*
529 * If s->r_start < rstart and
530 * s->r_end > rstart + count - 1, then
531 * we need to split the region into three pieces
532 * (the middle one will get returned to the user).
533 * Otherwise, we are allocating at either the
534 * beginning or the end of s, so we only need to
535 * split it in two. The first case requires
536 * two new allocations; the second requires but one.
537 */
538 rv = int_alloc_resource(M_NOWAIT);
539 if (rv == NULL)
540 goto out;
541 rv->r_start = rstart;
542 rv->r_end = rstart + count - 1;
543 rv->r_flags = new_rflags;
544 rv->r_dev = dev;
545 rv->r_rm = rm;
546
547 if (s->r_start < rv->r_start && s->r_end > rv->r_end) {
548 DPRINTF(("splitting region in three parts: "
549 "[%#lx, %#lx]; [%#lx, %#lx]; [%#lx, %#lx]\n",
550 s->r_start, rv->r_start - 1,
551 rv->r_start, rv->r_end,
552 rv->r_end + 1, s->r_end));
553 /*
554 * We are allocating in the middle.
555 */
556 r = int_alloc_resource(M_NOWAIT);
557 if (r == NULL) {
558 free(rv, M_RMAN);
559 rv = NULL;
560 goto out;
561 }
562 r->r_start = rv->r_end + 1;
563 r->r_end = s->r_end;
564 r->r_flags = s->r_flags;
565 r->r_rm = rm;
566 s->r_end = rv->r_start - 1;
567 TAILQ_INSERT_AFTER(&rm->rm_list, s, rv,
568 r_link);
569 TAILQ_INSERT_AFTER(&rm->rm_list, rv, r,
570 r_link);
571 } else if (s->r_start == rv->r_start) {
572 DPRINTF(("allocating from the beginning\n"));
573 /*
574 * We are allocating at the beginning.
575 */
576 s->r_start = rv->r_end + 1;
577 TAILQ_INSERT_BEFORE(s, rv, r_link);
578 } else {
579 DPRINTF(("allocating at the end\n"));
580 /*
581 * We are allocating at the end.
582 */
583 s->r_end = rv->r_start - 1;
584 TAILQ_INSERT_AFTER(&rm->rm_list, s, rv,
585 r_link);
586 }
587 goto out;
588 }
589 }
590
591 /*
592 * Now find an acceptable shared region, if the client's requirements
593 * allow sharing. By our implementation restriction, a candidate
594 * region must match exactly by both size and sharing type in order
595 * to be considered compatible with the client's request. (The
596 * former restriction could probably be lifted without too much
597 * additional work, but this does not seem warranted.)
598 */
599 DPRINTF(("no unshared regions found\n"));
600 if ((flags & RF_SHAREABLE) == 0)
601 goto out;
602
603 for (s = r; s && s->r_end <= end; s = TAILQ_NEXT(s, r_link)) {
604 if (SHARE_TYPE(s->r_flags) == SHARE_TYPE(flags) &&
605 s->r_start >= start &&
606 (s->r_end - s->r_start + 1) == count &&
607 (s->r_start & amask) == 0 &&
608 ((s->r_start ^ s->r_end) & bmask) == 0) {
609 rv = int_alloc_resource(M_NOWAIT);
610 if (rv == NULL)
611 goto out;
612 rv->r_start = s->r_start;
613 rv->r_end = s->r_end;
614 rv->r_flags = new_rflags;
615 rv->r_dev = dev;
616 rv->r_rm = rm;
617 if (s->r_sharehead == NULL) {
618 s->r_sharehead = malloc(sizeof *s->r_sharehead,
619 M_RMAN, M_NOWAIT | M_ZERO);
620 if (s->r_sharehead == NULL) {
621 free(rv, M_RMAN);
622 rv = NULL;
623 goto out;
624 }
625 LIST_INIT(s->r_sharehead);
626 LIST_INSERT_HEAD(s->r_sharehead, s,
627 r_sharelink);
628 s->r_flags |= RF_FIRSTSHARE;
629 }
630 rv->r_sharehead = s->r_sharehead;
631 LIST_INSERT_HEAD(s->r_sharehead, rv, r_sharelink);
632 goto out;
633 }
634 }
635 /*
636 * We couldn't find anything.
637 */
638
639 out:
640 mtx_unlock(rm->rm_mtx);
641 return (rv == NULL ? NULL : &rv->r_r);
642 }
643
644 struct resource *
645 rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count,
646 u_int flags, struct device *dev)
647 {
648
649 return (rman_reserve_resource_bound(rm, start, end, count, 0, flags,
650 dev));
651 }
652
653 int
654 rman_activate_resource(struct resource *re)
655 {
656 struct resource_i *r;
657 struct rman *rm;
658
659 r = re->__r_i;
660 rm = r->r_rm;
661 mtx_lock(rm->rm_mtx);
662 r->r_flags |= RF_ACTIVE;
663 mtx_unlock(rm->rm_mtx);
664 return 0;
665 }
666
667 int
668 rman_deactivate_resource(struct resource *r)
669 {
670 struct rman *rm;
671
672 rm = r->__r_i->r_rm;
673 mtx_lock(rm->rm_mtx);
674 r->__r_i->r_flags &= ~RF_ACTIVE;
675 mtx_unlock(rm->rm_mtx);
676 return 0;
677 }
678
679 static int
680 int_rman_release_resource(struct rman *rm, struct resource_i *r)
681 {
682 struct resource_i *s, *t;
683
684 if (r->r_flags & RF_ACTIVE)
685 r->r_flags &= ~RF_ACTIVE;
686
687 /*
688 * Check for a sharing list first. If there is one, then we don't
689 * have to think as hard.
690 */
691 if (r->r_sharehead) {
692 /*
693 * If a sharing list exists, then we know there are at
694 * least two sharers.
695 *
696 * If we are in the main circleq, appoint someone else.
697 */
698 LIST_REMOVE(r, r_sharelink);
699 s = LIST_FIRST(r->r_sharehead);
700 if (r->r_flags & RF_FIRSTSHARE) {
701 s->r_flags |= RF_FIRSTSHARE;
702 TAILQ_INSERT_BEFORE(r, s, r_link);
703 TAILQ_REMOVE(&rm->rm_list, r, r_link);
704 }
705
706 /*
707 * Make sure that the sharing list goes away completely
708 * if the resource is no longer being shared at all.
709 */
710 if (LIST_NEXT(s, r_sharelink) == NULL) {
711 free(s->r_sharehead, M_RMAN);
712 s->r_sharehead = NULL;
713 s->r_flags &= ~RF_FIRSTSHARE;
714 }
715 goto out;
716 }
717
718 /*
719 * Look at the adjacent resources in the list and see if our
720 * segment can be merged with any of them. If either of the
721 * resources is allocated or is not exactly adjacent then they
722 * cannot be merged with our segment.
723 */
724 s = TAILQ_PREV(r, resource_head, r_link);
725 if (s != NULL && ((s->r_flags & RF_ALLOCATED) != 0 ||
726 s->r_end + 1 != r->r_start))
727 s = NULL;
728 t = TAILQ_NEXT(r, r_link);
729 if (t != NULL && ((t->r_flags & RF_ALLOCATED) != 0 ||
730 r->r_end + 1 != t->r_start))
731 t = NULL;
732
733 if (s != NULL && t != NULL) {
734 /*
735 * Merge all three segments.
736 */
737 s->r_end = t->r_end;
738 TAILQ_REMOVE(&rm->rm_list, r, r_link);
739 TAILQ_REMOVE(&rm->rm_list, t, r_link);
740 free(t, M_RMAN);
741 } else if (s != NULL) {
742 /*
743 * Merge previous segment with ours.
744 */
745 s->r_end = r->r_end;
746 TAILQ_REMOVE(&rm->rm_list, r, r_link);
747 } else if (t != NULL) {
748 /*
749 * Merge next segment with ours.
750 */
751 t->r_start = r->r_start;
752 TAILQ_REMOVE(&rm->rm_list, r, r_link);
753 } else {
754 /*
755 * At this point, we know there is nothing we
756 * can potentially merge with, because on each
757 * side, there is either nothing there or what is
758 * there is still allocated. In that case, we don't
759 * want to remove r from the list; we simply want to
760 * change it to an unallocated region and return
761 * without freeing anything.
762 */
763 r->r_flags &= ~RF_ALLOCATED;
764 r->r_dev = NULL;
765 return 0;
766 }
767
768 out:
769 free(r, M_RMAN);
770 return 0;
771 }
772
773 int
774 rman_release_resource(struct resource *re)
775 {
776 int rv;
777 struct resource_i *r;
778 struct rman *rm;
779
780 r = re->__r_i;
781 rm = r->r_rm;
782 mtx_lock(rm->rm_mtx);
783 rv = int_rman_release_resource(rm, r);
784 mtx_unlock(rm->rm_mtx);
785 return (rv);
786 }
787
788 uint32_t
789 rman_make_alignment_flags(uint32_t size)
790 {
791 int i;
792
793 /*
794 * Find the hightest bit set, and add one if more than one bit
795 * set. We're effectively computing the ceil(log2(size)) here.
796 */
797 for (i = 31; i > 0; i--)
798 if ((1 << i) & size)
799 break;
800 if (~(1 << i) & size)
801 i++;
802
803 return(RF_ALIGNMENT_LOG2(i));
804 }
805
806 void
807 rman_set_start(struct resource *r, u_long start)
808 {
809
810 r->__r_i->r_start = start;
811 }
812
813 u_long
814 rman_get_start(struct resource *r)
815 {
816
817 return (r->__r_i->r_start);
818 }
819
820 void
821 rman_set_end(struct resource *r, u_long end)
822 {
823
824 r->__r_i->r_end = end;
825 }
826
827 u_long
828 rman_get_end(struct resource *r)
829 {
830
831 return (r->__r_i->r_end);
832 }
833
834 u_long
835 rman_get_size(struct resource *r)
836 {
837
838 return (r->__r_i->r_end - r->__r_i->r_start + 1);
839 }
840
841 u_int
842 rman_get_flags(struct resource *r)
843 {
844
845 return (r->__r_i->r_flags);
846 }
847
848 void
849 rman_set_virtual(struct resource *r, void *v)
850 {
851
852 r->__r_i->r_virtual = v;
853 }
854
855 void *
856 rman_get_virtual(struct resource *r)
857 {
858
859 return (r->__r_i->r_virtual);
860 }
861
862 void
863 rman_set_bustag(struct resource *r, bus_space_tag_t t)
864 {
865
866 r->r_bustag = t;
867 }
868
869 bus_space_tag_t
870 rman_get_bustag(struct resource *r)
871 {
872
873 return (r->r_bustag);
874 }
875
876 void
877 rman_set_bushandle(struct resource *r, bus_space_handle_t h)
878 {
879
880 r->r_bushandle = h;
881 }
882
883 bus_space_handle_t
884 rman_get_bushandle(struct resource *r)
885 {
886
887 return (r->r_bushandle);
888 }
889
890 void
891 rman_set_rid(struct resource *r, int rid)
892 {
893
894 r->__r_i->r_rid = rid;
895 }
896
897 int
898 rman_get_rid(struct resource *r)
899 {
900
901 return (r->__r_i->r_rid);
902 }
903
904 void
905 rman_set_device(struct resource *r, struct device *dev)
906 {
907
908 r->__r_i->r_dev = dev;
909 }
910
911 struct device *
912 rman_get_device(struct resource *r)
913 {
914
915 return (r->__r_i->r_dev);
916 }
917
918 int
919 rman_is_region_manager(struct resource *r, struct rman *rm)
920 {
921
922 return (r->__r_i->r_rm == rm);
923 }
924
925 /*
926 * Sysctl interface for scanning the resource lists.
927 *
928 * We take two input parameters; the index into the list of resource
929 * managers, and the resource offset into the list.
930 */
931 static int
932 sysctl_rman(SYSCTL_HANDLER_ARGS)
933 {
934 int *name = (int *)arg1;
935 u_int namelen = arg2;
936 int rman_idx, res_idx;
937 struct rman *rm;
938 struct resource_i *res;
939 struct resource_i *sres;
940 struct u_rman urm;
941 struct u_resource ures;
942 int error;
943
944 if (namelen != 3)
945 return (EINVAL);
946
947 if (bus_data_generation_check(name[0]))
948 return (EINVAL);
949 rman_idx = name[1];
950 res_idx = name[2];
951
952 /*
953 * Find the indexed resource manager
954 */
955 mtx_lock(&rman_mtx);
956 TAILQ_FOREACH(rm, &rman_head, rm_link) {
957 if (rman_idx-- == 0)
958 break;
959 }
960 mtx_unlock(&rman_mtx);
961 if (rm == NULL)
962 return (ENOENT);
963
964 /*
965 * If the resource index is -1, we want details on the
966 * resource manager.
967 */
968 if (res_idx == -1) {
969 bzero(&urm, sizeof(urm));
970 urm.rm_handle = (uintptr_t)rm;
971 if (rm->rm_descr != NULL)
972 strlcpy(urm.rm_descr, rm->rm_descr, RM_TEXTLEN);
973 urm.rm_start = rm->rm_start;
974 urm.rm_size = rm->rm_end - rm->rm_start + 1;
975 urm.rm_type = rm->rm_type;
976
977 error = SYSCTL_OUT(req, &urm, sizeof(urm));
978 return (error);
979 }
980
981 /*
982 * Find the indexed resource and return it.
983 */
984 mtx_lock(rm->rm_mtx);
985 TAILQ_FOREACH(res, &rm->rm_list, r_link) {
986 if (res->r_sharehead != NULL) {
987 LIST_FOREACH(sres, res->r_sharehead, r_sharelink)
988 if (res_idx-- == 0) {
989 res = sres;
990 goto found;
991 }
992 }
993 else if (res_idx-- == 0)
994 goto found;
995 }
996 mtx_unlock(rm->rm_mtx);
997 return (ENOENT);
998
999 found:
1000 bzero(&ures, sizeof(ures));
1001 ures.r_handle = (uintptr_t)res;
1002 ures.r_parent = (uintptr_t)res->r_rm;
1003 ures.r_device = (uintptr_t)res->r_dev;
1004 if (res->r_dev != NULL) {
1005 if (device_get_name(res->r_dev) != NULL) {
1006 snprintf(ures.r_devname, RM_TEXTLEN,
1007 "%s%d",
1008 device_get_name(res->r_dev),
1009 device_get_unit(res->r_dev));
1010 } else {
1011 strlcpy(ures.r_devname, "nomatch",
1012 RM_TEXTLEN);
1013 }
1014 } else {
1015 ures.r_devname[0] = '\0';
1016 }
1017 ures.r_start = res->r_start;
1018 ures.r_size = res->r_end - res->r_start + 1;
1019 ures.r_flags = res->r_flags;
1020
1021 mtx_unlock(rm->rm_mtx);
1022 error = SYSCTL_OUT(req, &ures, sizeof(ures));
1023 return (error);
1024 }
1025
1026 static SYSCTL_NODE(_hw_bus, OID_AUTO, rman, CTLFLAG_RD, sysctl_rman,
1027 "kernel resource manager");
1028
1029 #ifdef DDB
1030 static void
1031 dump_rman_header(struct rman *rm)
1032 {
1033
1034 if (db_pager_quit)
1035 return;
1036 db_printf("rman %p: %s (0x%lx-0x%lx full range)\n",
1037 rm, rm->rm_descr, rm->rm_start, rm->rm_end);
1038 }
1039
1040 static void
1041 dump_rman(struct rman *rm)
1042 {
1043 struct resource_i *r;
1044 const char *devname;
1045
1046 if (db_pager_quit)
1047 return;
1048 TAILQ_FOREACH(r, &rm->rm_list, r_link) {
1049 if (r->r_dev != NULL) {
1050 devname = device_get_nameunit(r->r_dev);
1051 if (devname == NULL)
1052 devname = "nomatch";
1053 } else
1054 devname = NULL;
1055 db_printf(" 0x%lx-0x%lx (RID=%d) ",
1056 r->r_start, r->r_end, r->r_rid);
1057 if (devname != NULL)
1058 db_printf("(%s)\n", devname);
1059 else
1060 db_printf("----\n");
1061 if (db_pager_quit)
1062 return;
1063 }
1064 }
1065
1066 DB_SHOW_COMMAND(rman, db_show_rman)
1067 {
1068
1069 if (have_addr) {
1070 dump_rman_header((struct rman *)addr);
1071 dump_rman((struct rman *)addr);
1072 }
1073 }
1074
1075 DB_SHOW_COMMAND(rmans, db_show_rmans)
1076 {
1077 struct rman *rm;
1078
1079 TAILQ_FOREACH(rm, &rman_head, rm_link) {
1080 dump_rman_header(rm);
1081 }
1082 }
1083
1084 DB_SHOW_ALL_COMMAND(rman, db_show_all_rman)
1085 {
1086 struct rman *rm;
1087
1088 TAILQ_FOREACH(rm, &rman_head, rm_link) {
1089 dump_rman_header(rm);
1090 dump_rman(rm);
1091 }
1092 }
1093 DB_SHOW_ALIAS(allrman, db_show_all_rman);
1094 #endif
Cache object: e286ebf8256ce96517d7d3a7765aa108
|