subr_rman.c revision 267961
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: head/sys/kern/subr_rman.c 267961 2014-06-27 16:33:43Z hselasky $"); 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 */ 88struct 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 102static int rman_debug = 0; 103SYSCTL_INT(_debug, OID_AUTO, rman_debug, CTLFLAG_RWTUN, 104 &rman_debug, 0, "rman debug"); 105 106#define DPRINTF(params) if (rman_debug) printf params 107 108static MALLOC_DEFINE(M_RMAN, "rman", "Resource manager"); 109 110struct rman_head rman_head; 111static struct mtx rman_mtx; /* mutex to protect rman_head */ 112static int int_rman_activate_resource(struct rman *rm, struct resource_i *r, 113 struct resource_i **whohas); 114static int int_rman_deactivate_resource(struct resource_i *r); 115static int int_rman_release_resource(struct rman *rm, struct resource_i *r); 116 117static __inline struct resource_i * 118int_alloc_resource(int malloc_flag) 119{ 120 struct resource_i *r; 121 122 r = malloc(sizeof *r, M_RMAN, malloc_flag | M_ZERO); 123 if (r != NULL) { 124 r->r_r.__r_i = r; 125 } 126 return (r); 127} 128 129int 130rman_init(struct rman *rm) 131{ 132 static int once = 0; 133 134 if (once == 0) { 135 once = 1; 136 TAILQ_INIT(&rman_head); 137 mtx_init(&rman_mtx, "rman head", NULL, MTX_DEF); 138 } 139 140 if (rm->rm_start == 0 && rm->rm_end == 0) 141 rm->rm_end = ~0ul; 142 if (rm->rm_type == RMAN_UNINIT) 143 panic("rman_init"); 144 if (rm->rm_type == RMAN_GAUGE) 145 panic("implement RMAN_GAUGE"); 146 147 TAILQ_INIT(&rm->rm_list); 148 rm->rm_mtx = malloc(sizeof *rm->rm_mtx, M_RMAN, M_NOWAIT | M_ZERO); 149 if (rm->rm_mtx == NULL) 150 return ENOMEM; 151 mtx_init(rm->rm_mtx, "rman", NULL, MTX_DEF); 152 153 mtx_lock(&rman_mtx); 154 TAILQ_INSERT_TAIL(&rman_head, rm, rm_link); 155 mtx_unlock(&rman_mtx); 156 return 0; 157} 158 159int 160rman_manage_region(struct rman *rm, u_long start, u_long end) 161{ 162 struct resource_i *r, *s, *t; 163 int rv = 0; 164 165 DPRINTF(("rman_manage_region: <%s> request: start %#lx, end %#lx\n", 166 rm->rm_descr, start, end)); 167 if (start < rm->rm_start || end > rm->rm_end) 168 return EINVAL; 169 r = int_alloc_resource(M_NOWAIT); 170 if (r == NULL) 171 return ENOMEM; 172 r->r_start = start; 173 r->r_end = end; 174 r->r_rm = rm; 175 176 mtx_lock(rm->rm_mtx); 177 178 /* Skip entries before us. */ 179 TAILQ_FOREACH(s, &rm->rm_list, r_link) { 180 if (s->r_end == ULONG_MAX) 181 break; 182 if (s->r_end + 1 >= r->r_start) 183 break; 184 } 185 186 /* If we ran off the end of the list, insert at the tail. */ 187 if (s == NULL) { 188 TAILQ_INSERT_TAIL(&rm->rm_list, r, r_link); 189 } else { 190 /* Check for any overlap with the current region. */ 191 if (r->r_start <= s->r_end && r->r_end >= s->r_start) { 192 rv = EBUSY; 193 goto out; 194 } 195 196 /* Check for any overlap with the next region. */ 197 t = TAILQ_NEXT(s, r_link); 198 if (t && r->r_start <= t->r_end && r->r_end >= t->r_start) { 199 rv = EBUSY; 200 goto out; 201 } 202 203 /* 204 * See if this region can be merged with the next region. If 205 * not, clear the pointer. 206 */ 207 if (t && (r->r_end + 1 != t->r_start || t->r_flags != 0)) 208 t = NULL; 209 210 /* See if we can merge with the current region. */ 211 if (s->r_end + 1 == r->r_start && s->r_flags == 0) { 212 /* Can we merge all 3 regions? */ 213 if (t != NULL) { 214 s->r_end = t->r_end; 215 TAILQ_REMOVE(&rm->rm_list, t, r_link); 216 free(r, M_RMAN); 217 free(t, M_RMAN); 218 } else { 219 s->r_end = r->r_end; 220 free(r, M_RMAN); 221 } 222 } else if (t != NULL) { 223 /* Can we merge with just the next region? */ 224 t->r_start = r->r_start; 225 free(r, M_RMAN); 226 } else if (s->r_end < r->r_start) { 227 TAILQ_INSERT_AFTER(&rm->rm_list, s, r, r_link); 228 } else { 229 TAILQ_INSERT_BEFORE(s, r, r_link); 230 } 231 } 232out: 233 mtx_unlock(rm->rm_mtx); 234 return rv; 235} 236 237int 238rman_init_from_resource(struct rman *rm, struct resource *r) 239{ 240 int rv; 241 242 if ((rv = rman_init(rm)) != 0) 243 return (rv); 244 return (rman_manage_region(rm, r->__r_i->r_start, r->__r_i->r_end)); 245} 246 247int 248rman_fini(struct rman *rm) 249{ 250 struct resource_i *r; 251 252 mtx_lock(rm->rm_mtx); 253 TAILQ_FOREACH(r, &rm->rm_list, r_link) { 254 if (r->r_flags & RF_ALLOCATED) { 255 mtx_unlock(rm->rm_mtx); 256 return EBUSY; 257 } 258 } 259 260 /* 261 * There really should only be one of these if we are in this 262 * state and the code is working properly, but it can't hurt. 263 */ 264 while (!TAILQ_EMPTY(&rm->rm_list)) { 265 r = TAILQ_FIRST(&rm->rm_list); 266 TAILQ_REMOVE(&rm->rm_list, r, r_link); 267 free(r, M_RMAN); 268 } 269 mtx_unlock(rm->rm_mtx); 270 mtx_lock(&rman_mtx); 271 TAILQ_REMOVE(&rman_head, rm, rm_link); 272 mtx_unlock(&rman_mtx); 273 mtx_destroy(rm->rm_mtx); 274 free(rm->rm_mtx, M_RMAN); 275 276 return 0; 277} 278 279int 280rman_first_free_region(struct rman *rm, u_long *start, u_long *end) 281{ 282 struct resource_i *r; 283 284 mtx_lock(rm->rm_mtx); 285 TAILQ_FOREACH(r, &rm->rm_list, r_link) { 286 if (!(r->r_flags & RF_ALLOCATED)) { 287 *start = r->r_start; 288 *end = r->r_end; 289 mtx_unlock(rm->rm_mtx); 290 return (0); 291 } 292 } 293 mtx_unlock(rm->rm_mtx); 294 return (ENOENT); 295} 296 297int 298rman_last_free_region(struct rman *rm, u_long *start, u_long *end) 299{ 300 struct resource_i *r; 301 302 mtx_lock(rm->rm_mtx); 303 TAILQ_FOREACH_REVERSE(r, &rm->rm_list, resource_head, r_link) { 304 if (!(r->r_flags & RF_ALLOCATED)) { 305 *start = r->r_start; 306 *end = r->r_end; 307 mtx_unlock(rm->rm_mtx); 308 return (0); 309 } 310 } 311 mtx_unlock(rm->rm_mtx); 312 return (ENOENT); 313} 314 315/* Shrink or extend one or both ends of an allocated resource. */ 316int 317rman_adjust_resource(struct resource *rr, u_long start, u_long end) 318{ 319 struct resource_i *r, *s, *t, *new; 320 struct rman *rm; 321 322 /* Not supported for shared resources. */ 323 r = rr->__r_i; 324 if (r->r_flags & (RF_TIMESHARE | RF_SHAREABLE)) 325 return (EINVAL); 326 327 /* 328 * This does not support wholesale moving of a resource. At 329 * least part of the desired new range must overlap with the 330 * existing resource. 331 */ 332 if (end < r->r_start || r->r_end < start) 333 return (EINVAL); 334 335 /* 336 * Find the two resource regions immediately adjacent to the 337 * allocated resource. 338 */ 339 rm = r->r_rm; 340 mtx_lock(rm->rm_mtx); 341#ifdef INVARIANTS 342 TAILQ_FOREACH(s, &rm->rm_list, r_link) { 343 if (s == r) 344 break; 345 } 346 if (s == NULL) 347 panic("resource not in list"); 348#endif 349 s = TAILQ_PREV(r, resource_head, r_link); 350 t = TAILQ_NEXT(r, r_link); 351 KASSERT(s == NULL || s->r_end + 1 == r->r_start, 352 ("prev resource mismatch")); 353 KASSERT(t == NULL || r->r_end + 1 == t->r_start, 354 ("next resource mismatch")); 355 356 /* 357 * See if the changes are permitted. Shrinking is always allowed, 358 * but growing requires sufficient room in the adjacent region. 359 */ 360 if (start < r->r_start && (s == NULL || (s->r_flags & RF_ALLOCATED) || 361 s->r_start > start)) { 362 mtx_unlock(rm->rm_mtx); 363 return (EBUSY); 364 } 365 if (end > r->r_end && (t == NULL || (t->r_flags & RF_ALLOCATED) || 366 t->r_end < end)) { 367 mtx_unlock(rm->rm_mtx); 368 return (EBUSY); 369 } 370 371 /* 372 * While holding the lock, grow either end of the resource as 373 * needed and shrink either end if the shrinking does not require 374 * allocating a new resource. We can safely drop the lock and then 375 * insert a new range to handle the shrinking case afterwards. 376 */ 377 if (start < r->r_start || 378 (start > r->r_start && s != NULL && !(s->r_flags & RF_ALLOCATED))) { 379 KASSERT(s->r_flags == 0, ("prev is busy")); 380 r->r_start = start; 381 if (s->r_start == start) { 382 TAILQ_REMOVE(&rm->rm_list, s, r_link); 383 free(s, M_RMAN); 384 } else 385 s->r_end = start - 1; 386 } 387 if (end > r->r_end || 388 (end < r->r_end && t != NULL && !(t->r_flags & RF_ALLOCATED))) { 389 KASSERT(t->r_flags == 0, ("next is busy")); 390 r->r_end = end; 391 if (t->r_end == end) { 392 TAILQ_REMOVE(&rm->rm_list, t, r_link); 393 free(t, M_RMAN); 394 } else 395 t->r_start = end + 1; 396 } 397 mtx_unlock(rm->rm_mtx); 398 399 /* 400 * Handle the shrinking cases that require allocating a new 401 * resource to hold the newly-free region. We have to recheck 402 * if we still need this new region after acquiring the lock. 403 */ 404 if (start > r->r_start) { 405 new = int_alloc_resource(M_WAITOK); 406 new->r_start = r->r_start; 407 new->r_end = start - 1; 408 new->r_rm = rm; 409 mtx_lock(rm->rm_mtx); 410 r->r_start = start; 411 s = TAILQ_PREV(r, resource_head, r_link); 412 if (s != NULL && !(s->r_flags & RF_ALLOCATED)) { 413 s->r_end = start - 1; 414 free(new, M_RMAN); 415 } else 416 TAILQ_INSERT_BEFORE(r, new, r_link); 417 mtx_unlock(rm->rm_mtx); 418 } 419 if (end < r->r_end) { 420 new = int_alloc_resource(M_WAITOK); 421 new->r_start = end + 1; 422 new->r_end = r->r_end; 423 new->r_rm = rm; 424 mtx_lock(rm->rm_mtx); 425 r->r_end = end; 426 t = TAILQ_NEXT(r, r_link); 427 if (t != NULL && !(t->r_flags & RF_ALLOCATED)) { 428 t->r_start = end + 1; 429 free(new, M_RMAN); 430 } else 431 TAILQ_INSERT_AFTER(&rm->rm_list, r, new, r_link); 432 mtx_unlock(rm->rm_mtx); 433 } 434 return (0); 435} 436 437#define SHARE_TYPE(f) (f & (RF_SHAREABLE | RF_TIMESHARE | RF_PREFETCHABLE)) 438 439struct resource * 440rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end, 441 u_long count, u_long bound, u_int flags, 442 struct device *dev) 443{ 444 u_int new_rflags; 445 struct resource_i *r, *s, *rv; 446 u_long rstart, rend, amask, bmask; 447 448 rv = NULL; 449 450 DPRINTF(("rman_reserve_resource_bound: <%s> request: [%#lx, %#lx], " 451 "length %#lx, flags %u, device %s\n", rm->rm_descr, start, end, 452 count, flags, 453 dev == NULL ? "<null>" : device_get_nameunit(dev))); 454 KASSERT((flags & (RF_WANTED | RF_FIRSTSHARE)) == 0, 455 ("invalid flags %#x", flags)); 456 new_rflags = (flags & ~(RF_ACTIVE | RF_WANTED | RF_FIRSTSHARE)) | 457 RF_ALLOCATED; 458 459 mtx_lock(rm->rm_mtx); 460 461 for (r = TAILQ_FIRST(&rm->rm_list); 462 r && r->r_end < start + count - 1; 463 r = TAILQ_NEXT(r, r_link)) 464 ; 465 466 if (r == NULL) { 467 DPRINTF(("could not find a region\n")); 468 goto out; 469 } 470 471 amask = (1ul << RF_ALIGNMENT(flags)) - 1; 472 KASSERT(start <= ULONG_MAX - amask, 473 ("start (%#lx) + amask (%#lx) would wrap around", start, amask)); 474 475 /* If bound is 0, bmask will also be 0 */ 476 bmask = ~(bound - 1); 477 /* 478 * First try to find an acceptable totally-unshared region. 479 */ 480 for (s = r; s; s = TAILQ_NEXT(s, r_link)) { 481 DPRINTF(("considering [%#lx, %#lx]\n", s->r_start, s->r_end)); 482 /* 483 * The resource list is sorted, so there is no point in 484 * searching further once r_start is too large. 485 */ 486 if (s->r_start > end - (count - 1)) { 487 DPRINTF(("s->r_start (%#lx) + count - 1> end (%#lx)\n", 488 s->r_start, end)); 489 break; 490 } 491 if (s->r_start > ULONG_MAX - amask) { 492 DPRINTF(("s->r_start (%#lx) + amask (%#lx) too large\n", 493 s->r_start, amask)); 494 break; 495 } 496 if (s->r_flags & RF_ALLOCATED) { 497 DPRINTF(("region is allocated\n")); 498 continue; 499 } 500 rstart = ulmax(s->r_start, start); 501 /* 502 * Try to find a region by adjusting to boundary and alignment 503 * until both conditions are satisfied. This is not an optimal 504 * algorithm, but in most cases it isn't really bad, either. 505 */ 506 do { 507 rstart = (rstart + amask) & ~amask; 508 if (((rstart ^ (rstart + count - 1)) & bmask) != 0) 509 rstart += bound - (rstart & ~bmask); 510 } while ((rstart & amask) != 0 && rstart < end && 511 rstart < s->r_end); 512 rend = ulmin(s->r_end, ulmax(rstart + count - 1, end)); 513 if (rstart > rend) { 514 DPRINTF(("adjusted start exceeds end\n")); 515 continue; 516 } 517 DPRINTF(("truncated region: [%#lx, %#lx]; size %#lx (requested %#lx)\n", 518 rstart, rend, (rend - rstart + 1), count)); 519 520 if ((rend - rstart + 1) >= count) { 521 DPRINTF(("candidate region: [%#lx, %#lx], size %#lx\n", 522 rstart, rend, (rend - rstart + 1))); 523 if ((s->r_end - s->r_start + 1) == count) { 524 DPRINTF(("candidate region is entire chunk\n")); 525 rv = s; 526 rv->r_flags = new_rflags; 527 rv->r_dev = dev; 528 goto out; 529 } 530 531 /* 532 * If s->r_start < rstart and 533 * s->r_end > rstart + count - 1, then 534 * we need to split the region into three pieces 535 * (the middle one will get returned to the user). 536 * Otherwise, we are allocating at either the 537 * beginning or the end of s, so we only need to 538 * split it in two. The first case requires 539 * two new allocations; the second requires but one. 540 */ 541 rv = int_alloc_resource(M_NOWAIT); 542 if (rv == NULL) 543 goto out; 544 rv->r_start = rstart; 545 rv->r_end = rstart + count - 1; 546 rv->r_flags = new_rflags; 547 rv->r_dev = dev; 548 rv->r_rm = rm; 549 550 if (s->r_start < rv->r_start && s->r_end > rv->r_end) { 551 DPRINTF(("splitting region in three parts: " 552 "[%#lx, %#lx]; [%#lx, %#lx]; [%#lx, %#lx]\n", 553 s->r_start, rv->r_start - 1, 554 rv->r_start, rv->r_end, 555 rv->r_end + 1, s->r_end)); 556 /* 557 * We are allocating in the middle. 558 */ 559 r = int_alloc_resource(M_NOWAIT); 560 if (r == NULL) { 561 free(rv, M_RMAN); 562 rv = NULL; 563 goto out; 564 } 565 r->r_start = rv->r_end + 1; 566 r->r_end = s->r_end; 567 r->r_flags = s->r_flags; 568 r->r_rm = rm; 569 s->r_end = rv->r_start - 1; 570 TAILQ_INSERT_AFTER(&rm->rm_list, s, rv, 571 r_link); 572 TAILQ_INSERT_AFTER(&rm->rm_list, rv, r, 573 r_link); 574 } else if (s->r_start == rv->r_start) { 575 DPRINTF(("allocating from the beginning\n")); 576 /* 577 * We are allocating at the beginning. 578 */ 579 s->r_start = rv->r_end + 1; 580 TAILQ_INSERT_BEFORE(s, rv, r_link); 581 } else { 582 DPRINTF(("allocating at the end\n")); 583 /* 584 * We are allocating at the end. 585 */ 586 s->r_end = rv->r_start - 1; 587 TAILQ_INSERT_AFTER(&rm->rm_list, s, rv, 588 r_link); 589 } 590 goto out; 591 } 592 } 593 594 /* 595 * Now find an acceptable shared region, if the client's requirements 596 * allow sharing. By our implementation restriction, a candidate 597 * region must match exactly by both size and sharing type in order 598 * to be considered compatible with the client's request. (The 599 * former restriction could probably be lifted without too much 600 * additional work, but this does not seem warranted.) 601 */ 602 DPRINTF(("no unshared regions found\n")); 603 if ((flags & (RF_SHAREABLE | RF_TIMESHARE)) == 0) 604 goto out; 605 606 for (s = r; s && s->r_end <= end; s = TAILQ_NEXT(s, r_link)) { 607 if (SHARE_TYPE(s->r_flags) == SHARE_TYPE(flags) && 608 s->r_start >= start && 609 (s->r_end - s->r_start + 1) == count && 610 (s->r_start & amask) == 0 && 611 ((s->r_start ^ s->r_end) & bmask) == 0) { 612 rv = int_alloc_resource(M_NOWAIT); 613 if (rv == NULL) 614 goto out; 615 rv->r_start = s->r_start; 616 rv->r_end = s->r_end; 617 rv->r_flags = new_rflags; 618 rv->r_dev = dev; 619 rv->r_rm = rm; 620 if (s->r_sharehead == NULL) { 621 s->r_sharehead = malloc(sizeof *s->r_sharehead, 622 M_RMAN, M_NOWAIT | M_ZERO); 623 if (s->r_sharehead == NULL) { 624 free(rv, M_RMAN); 625 rv = NULL; 626 goto out; 627 } 628 LIST_INIT(s->r_sharehead); 629 LIST_INSERT_HEAD(s->r_sharehead, s, 630 r_sharelink); 631 s->r_flags |= RF_FIRSTSHARE; 632 } 633 rv->r_sharehead = s->r_sharehead; 634 LIST_INSERT_HEAD(s->r_sharehead, rv, r_sharelink); 635 goto out; 636 } 637 } 638 639 /* 640 * We couldn't find anything. 641 */ 642out: 643 /* 644 * If the user specified RF_ACTIVE in flags, we attempt to atomically 645 * activate the resource. If this fails, we release the resource 646 * and indicate overall failure. (This behavior probably doesn't 647 * make sense for RF_TIMESHARE-type resources.) 648 */ 649 if (rv && (flags & RF_ACTIVE) != 0) { 650 struct resource_i *whohas; 651 if (int_rman_activate_resource(rm, rv, &whohas)) { 652 int_rman_release_resource(rm, rv); 653 rv = NULL; 654 } 655 } 656 657 mtx_unlock(rm->rm_mtx); 658 return (rv == NULL ? NULL : &rv->r_r); 659} 660 661struct resource * 662rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count, 663 u_int flags, struct device *dev) 664{ 665 666 return (rman_reserve_resource_bound(rm, start, end, count, 0, flags, 667 dev)); 668} 669 670static int 671int_rman_activate_resource(struct rman *rm, struct resource_i *r, 672 struct resource_i **whohas) 673{ 674 struct resource_i *s; 675 int ok; 676 677 /* 678 * If we are not timesharing, then there is nothing much to do. 679 * If we already have the resource, then there is nothing at all to do. 680 * If we are not on a sharing list with anybody else, then there is 681 * little to do. 682 */ 683 if ((r->r_flags & RF_TIMESHARE) == 0 684 || (r->r_flags & RF_ACTIVE) != 0 685 || r->r_sharehead == NULL) { 686 r->r_flags |= RF_ACTIVE; 687 return 0; 688 } 689 690 ok = 1; 691 for (s = LIST_FIRST(r->r_sharehead); s && ok; 692 s = LIST_NEXT(s, r_sharelink)) { 693 if ((s->r_flags & RF_ACTIVE) != 0) { 694 ok = 0; 695 *whohas = s; 696 } 697 } 698 if (ok) { 699 r->r_flags |= RF_ACTIVE; 700 return 0; 701 } 702 return EBUSY; 703} 704 705int 706rman_activate_resource(struct resource *re) 707{ 708 int rv; 709 struct resource_i *r, *whohas; 710 struct rman *rm; 711 712 r = re->__r_i; 713 rm = r->r_rm; 714 mtx_lock(rm->rm_mtx); 715 rv = int_rman_activate_resource(rm, r, &whohas); 716 mtx_unlock(rm->rm_mtx); 717 return rv; 718} 719 720int 721rman_await_resource(struct resource *re, int pri, int timo) 722{ 723 int rv; 724 struct resource_i *r, *whohas; 725 struct rman *rm; 726 727 r = re->__r_i; 728 rm = r->r_rm; 729 mtx_lock(rm->rm_mtx); 730 for (;;) { 731 rv = int_rman_activate_resource(rm, r, &whohas); 732 if (rv != EBUSY) 733 return (rv); /* returns with mutex held */ 734 735 if (r->r_sharehead == NULL) 736 panic("rman_await_resource"); 737 whohas->r_flags |= RF_WANTED; 738 rv = msleep(r->r_sharehead, rm->rm_mtx, pri, "rmwait", timo); 739 if (rv) { 740 mtx_unlock(rm->rm_mtx); 741 return (rv); 742 } 743 } 744} 745 746static int 747int_rman_deactivate_resource(struct resource_i *r) 748{ 749 750 r->r_flags &= ~RF_ACTIVE; 751 if (r->r_flags & RF_WANTED) { 752 r->r_flags &= ~RF_WANTED; 753 wakeup(r->r_sharehead); 754 } 755 return 0; 756} 757 758int 759rman_deactivate_resource(struct resource *r) 760{ 761 struct rman *rm; 762 763 rm = r->__r_i->r_rm; 764 mtx_lock(rm->rm_mtx); 765 int_rman_deactivate_resource(r->__r_i); 766 mtx_unlock(rm->rm_mtx); 767 return 0; 768} 769 770static int 771int_rman_release_resource(struct rman *rm, struct resource_i *r) 772{ 773 struct resource_i *s, *t; 774 775 if (r->r_flags & RF_ACTIVE) 776 int_rman_deactivate_resource(r); 777 778 /* 779 * Check for a sharing list first. If there is one, then we don't 780 * have to think as hard. 781 */ 782 if (r->r_sharehead) { 783 /* 784 * If a sharing list exists, then we know there are at 785 * least two sharers. 786 * 787 * If we are in the main circleq, appoint someone else. 788 */ 789 LIST_REMOVE(r, r_sharelink); 790 s = LIST_FIRST(r->r_sharehead); 791 if (r->r_flags & RF_FIRSTSHARE) { 792 s->r_flags |= RF_FIRSTSHARE; 793 TAILQ_INSERT_BEFORE(r, s, r_link); 794 TAILQ_REMOVE(&rm->rm_list, r, r_link); 795 } 796 797 /* 798 * Make sure that the sharing list goes away completely 799 * if the resource is no longer being shared at all. 800 */ 801 if (LIST_NEXT(s, r_sharelink) == NULL) { 802 free(s->r_sharehead, M_RMAN); 803 s->r_sharehead = NULL; 804 s->r_flags &= ~RF_FIRSTSHARE; 805 } 806 goto out; 807 } 808 809 /* 810 * Look at the adjacent resources in the list and see if our 811 * segment can be merged with any of them. If either of the 812 * resources is allocated or is not exactly adjacent then they 813 * cannot be merged with our segment. 814 */ 815 s = TAILQ_PREV(r, resource_head, r_link); 816 if (s != NULL && ((s->r_flags & RF_ALLOCATED) != 0 || 817 s->r_end + 1 != r->r_start)) 818 s = NULL; 819 t = TAILQ_NEXT(r, r_link); 820 if (t != NULL && ((t->r_flags & RF_ALLOCATED) != 0 || 821 r->r_end + 1 != t->r_start)) 822 t = NULL; 823 824 if (s != NULL && t != NULL) { 825 /* 826 * Merge all three segments. 827 */ 828 s->r_end = t->r_end; 829 TAILQ_REMOVE(&rm->rm_list, r, r_link); 830 TAILQ_REMOVE(&rm->rm_list, t, r_link); 831 free(t, M_RMAN); 832 } else if (s != NULL) { 833 /* 834 * Merge previous segment with ours. 835 */ 836 s->r_end = r->r_end; 837 TAILQ_REMOVE(&rm->rm_list, r, r_link); 838 } else if (t != NULL) { 839 /* 840 * Merge next segment with ours. 841 */ 842 t->r_start = r->r_start; 843 TAILQ_REMOVE(&rm->rm_list, r, r_link); 844 } else { 845 /* 846 * At this point, we know there is nothing we 847 * can potentially merge with, because on each 848 * side, there is either nothing there or what is 849 * there is still allocated. In that case, we don't 850 * want to remove r from the list; we simply want to 851 * change it to an unallocated region and return 852 * without freeing anything. 853 */ 854 r->r_flags &= ~RF_ALLOCATED; 855 r->r_dev = NULL; 856 return 0; 857 } 858 859out: 860 free(r, M_RMAN); 861 return 0; 862} 863 864int 865rman_release_resource(struct resource *re) 866{ 867 int rv; 868 struct resource_i *r; 869 struct rman *rm; 870 871 r = re->__r_i; 872 rm = r->r_rm; 873 mtx_lock(rm->rm_mtx); 874 rv = int_rman_release_resource(rm, r); 875 mtx_unlock(rm->rm_mtx); 876 return (rv); 877} 878 879uint32_t 880rman_make_alignment_flags(uint32_t size) 881{ 882 int i; 883 884 /* 885 * Find the hightest bit set, and add one if more than one bit 886 * set. We're effectively computing the ceil(log2(size)) here. 887 */ 888 for (i = 31; i > 0; i--) 889 if ((1 << i) & size) 890 break; 891 if (~(1 << i) & size) 892 i++; 893 894 return(RF_ALIGNMENT_LOG2(i)); 895} 896 897void 898rman_set_start(struct resource *r, u_long start) 899{ 900 r->__r_i->r_start = start; 901} 902 903u_long 904rman_get_start(struct resource *r) 905{ 906 return (r->__r_i->r_start); 907} 908 909void 910rman_set_end(struct resource *r, u_long end) 911{ 912 r->__r_i->r_end = end; 913} 914 915u_long 916rman_get_end(struct resource *r) 917{ 918 return (r->__r_i->r_end); 919} 920 921u_long 922rman_get_size(struct resource *r) 923{ 924 return (r->__r_i->r_end - r->__r_i->r_start + 1); 925} 926 927u_int 928rman_get_flags(struct resource *r) 929{ 930 return (r->__r_i->r_flags); 931} 932 933void 934rman_set_virtual(struct resource *r, void *v) 935{ 936 r->__r_i->r_virtual = v; 937} 938 939void * 940rman_get_virtual(struct resource *r) 941{ 942 return (r->__r_i->r_virtual); 943} 944 945void 946rman_set_bustag(struct resource *r, bus_space_tag_t t) 947{ 948 r->r_bustag = t; 949} 950 951bus_space_tag_t 952rman_get_bustag(struct resource *r) 953{ 954 return (r->r_bustag); 955} 956 957void 958rman_set_bushandle(struct resource *r, bus_space_handle_t h) 959{ 960 r->r_bushandle = h; 961} 962 963bus_space_handle_t 964rman_get_bushandle(struct resource *r) 965{ 966 return (r->r_bushandle); 967} 968 969void 970rman_set_rid(struct resource *r, int rid) 971{ 972 r->__r_i->r_rid = rid; 973} 974 975int 976rman_get_rid(struct resource *r) 977{ 978 return (r->__r_i->r_rid); 979} 980 981void 982rman_set_device(struct resource *r, struct device *dev) 983{ 984 r->__r_i->r_dev = dev; 985} 986 987struct device * 988rman_get_device(struct resource *r) 989{ 990 return (r->__r_i->r_dev); 991} 992 993int 994rman_is_region_manager(struct resource *r, struct rman *rm) 995{ 996 997 return (r->__r_i->r_rm == rm); 998} 999 1000/* 1001 * Sysctl interface for scanning the resource lists. 1002 * 1003 * We take two input parameters; the index into the list of resource 1004 * managers, and the resource offset into the list. 1005 */ 1006static int 1007sysctl_rman(SYSCTL_HANDLER_ARGS) 1008{ 1009 int *name = (int *)arg1; 1010 u_int namelen = arg2; 1011 int rman_idx, res_idx; 1012 struct rman *rm; 1013 struct resource_i *res; 1014 struct resource_i *sres; 1015 struct u_rman urm; 1016 struct u_resource ures; 1017 int error; 1018 1019 if (namelen != 3) 1020 return (EINVAL); 1021 1022 if (bus_data_generation_check(name[0])) 1023 return (EINVAL); 1024 rman_idx = name[1]; 1025 res_idx = name[2]; 1026 1027 /* 1028 * Find the indexed resource manager 1029 */ 1030 mtx_lock(&rman_mtx); 1031 TAILQ_FOREACH(rm, &rman_head, rm_link) { 1032 if (rman_idx-- == 0) 1033 break; 1034 } 1035 mtx_unlock(&rman_mtx); 1036 if (rm == NULL) 1037 return (ENOENT); 1038 1039 /* 1040 * If the resource index is -1, we want details on the 1041 * resource manager. 1042 */ 1043 if (res_idx == -1) { 1044 bzero(&urm, sizeof(urm)); 1045 urm.rm_handle = (uintptr_t)rm; 1046 if (rm->rm_descr != NULL) 1047 strlcpy(urm.rm_descr, rm->rm_descr, RM_TEXTLEN); 1048 urm.rm_start = rm->rm_start; 1049 urm.rm_size = rm->rm_end - rm->rm_start + 1; 1050 urm.rm_type = rm->rm_type; 1051 1052 error = SYSCTL_OUT(req, &urm, sizeof(urm)); 1053 return (error); 1054 } 1055 1056 /* 1057 * Find the indexed resource and return it. 1058 */ 1059 mtx_lock(rm->rm_mtx); 1060 TAILQ_FOREACH(res, &rm->rm_list, r_link) { 1061 if (res->r_sharehead != NULL) { 1062 LIST_FOREACH(sres, res->r_sharehead, r_sharelink) 1063 if (res_idx-- == 0) { 1064 res = sres; 1065 goto found; 1066 } 1067 } 1068 else if (res_idx-- == 0) 1069 goto found; 1070 } 1071 mtx_unlock(rm->rm_mtx); 1072 return (ENOENT); 1073 1074found: 1075 bzero(&ures, sizeof(ures)); 1076 ures.r_handle = (uintptr_t)res; 1077 ures.r_parent = (uintptr_t)res->r_rm; 1078 ures.r_device = (uintptr_t)res->r_dev; 1079 if (res->r_dev != NULL) { 1080 if (device_get_name(res->r_dev) != NULL) { 1081 snprintf(ures.r_devname, RM_TEXTLEN, 1082 "%s%d", 1083 device_get_name(res->r_dev), 1084 device_get_unit(res->r_dev)); 1085 } else { 1086 strlcpy(ures.r_devname, "nomatch", 1087 RM_TEXTLEN); 1088 } 1089 } else { 1090 ures.r_devname[0] = '\0'; 1091 } 1092 ures.r_start = res->r_start; 1093 ures.r_size = res->r_end - res->r_start + 1; 1094 ures.r_flags = res->r_flags; 1095 1096 mtx_unlock(rm->rm_mtx); 1097 error = SYSCTL_OUT(req, &ures, sizeof(ures)); 1098 return (error); 1099} 1100 1101static SYSCTL_NODE(_hw_bus, OID_AUTO, rman, CTLFLAG_RD, sysctl_rman, 1102 "kernel resource manager"); 1103 1104#ifdef DDB 1105static void 1106dump_rman_header(struct rman *rm) 1107{ 1108 1109 if (db_pager_quit) 1110 return; 1111 db_printf("rman %p: %s (0x%lx-0x%lx full range)\n", 1112 rm, rm->rm_descr, rm->rm_start, rm->rm_end); 1113} 1114 1115static void 1116dump_rman(struct rman *rm) 1117{ 1118 struct resource_i *r; 1119 const char *devname; 1120 1121 if (db_pager_quit) 1122 return; 1123 TAILQ_FOREACH(r, &rm->rm_list, r_link) { 1124 if (r->r_dev != NULL) { 1125 devname = device_get_nameunit(r->r_dev); 1126 if (devname == NULL) 1127 devname = "nomatch"; 1128 } else 1129 devname = NULL; 1130 db_printf(" 0x%lx-0x%lx ", r->r_start, r->r_end); 1131 if (devname != NULL) 1132 db_printf("(%s)\n", devname); 1133 else 1134 db_printf("----\n"); 1135 if (db_pager_quit) 1136 return; 1137 } 1138} 1139 1140DB_SHOW_COMMAND(rman, db_show_rman) 1141{ 1142 1143 if (have_addr) { 1144 dump_rman_header((struct rman *)addr); 1145 dump_rman((struct rman *)addr); 1146 } 1147} 1148 1149DB_SHOW_COMMAND(rmans, db_show_rmans) 1150{ 1151 struct rman *rm; 1152 1153 TAILQ_FOREACH(rm, &rman_head, rm_link) { 1154 dump_rman_header(rm); 1155 } 1156} 1157 1158DB_SHOW_ALL_COMMAND(rman, db_show_all_rman) 1159{ 1160 struct rman *rm; 1161 1162 TAILQ_FOREACH(rm, &rman_head, rm_link) { 1163 dump_rman_header(rm); 1164 dump_rman(rm); 1165 } 1166} 1167DB_SHOW_ALIAS(allrman, db_show_all_rman); 1168#endif 1169