The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


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FreeBSD/Linux Kernel Cross Reference
sys/kern/subr_rman.c

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    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 <sys/cdefs.h>
   59 __FBSDID("$FreeBSD: releng/5.3/sys/kern/subr_rman.c 136588 2004-10-16 08:43:07Z cvs2svn $");
   60 
   61 #define __RMAN_RESOURCE_VISIBLE
   62 #include <sys/param.h>
   63 #include <sys/systm.h>
   64 #include <sys/kernel.h>
   65 #include <sys/lock.h>
   66 #include <sys/malloc.h>
   67 #include <sys/mutex.h>
   68 #include <sys/bus.h>            /* XXX debugging */
   69 #include <machine/bus.h>
   70 #include <sys/rman.h>
   71 #include <sys/sysctl.h>
   72 
   73 int     rman_debug = 0;
   74 TUNABLE_INT("debug.rman_debug", &rman_debug);
   75 SYSCTL_INT(_debug, OID_AUTO, rman_debug, CTLFLAG_RW,
   76     &rman_debug, 0, "rman debug");
   77 
   78 #define DPRINTF(params) if (rman_debug) printf params
   79 
   80 static MALLOC_DEFINE(M_RMAN, "rman", "Resource manager");
   81 
   82 struct  rman_head rman_head;
   83 static  struct mtx rman_mtx; /* mutex to protect rman_head */
   84 static  int int_rman_activate_resource(struct rman *rm, struct resource *r,
   85                                        struct resource **whohas);
   86 static  int int_rman_deactivate_resource(struct resource *r);
   87 static  int int_rman_release_resource(struct rman *rm, struct resource *r);
   88 
   89 int
   90 rman_init(struct rman *rm)
   91 {
   92         static int once;
   93 
   94         if (once == 0) {
   95                 once = 1;
   96                 TAILQ_INIT(&rman_head);
   97                 mtx_init(&rman_mtx, "rman head", NULL, MTX_DEF);
   98         }
   99 
  100         if (rm->rm_type == RMAN_UNINIT)
  101                 panic("rman_init");
  102         if (rm->rm_type == RMAN_GAUGE)
  103                 panic("implement RMAN_GAUGE");
  104 
  105         TAILQ_INIT(&rm->rm_list);
  106         rm->rm_mtx = malloc(sizeof *rm->rm_mtx, M_RMAN, M_NOWAIT | M_ZERO);
  107         if (rm->rm_mtx == 0)
  108                 return ENOMEM;
  109         mtx_init(rm->rm_mtx, "rman", NULL, MTX_DEF);
  110 
  111         mtx_lock(&rman_mtx);
  112         TAILQ_INSERT_TAIL(&rman_head, rm, rm_link);
  113         mtx_unlock(&rman_mtx);
  114         return 0;
  115 }
  116 
  117 /*
  118  * NB: this interface is not robust against programming errors which
  119  * add multiple copies of the same region.
  120  */
  121 int
  122 rman_manage_region(struct rman *rm, u_long start, u_long end)
  123 {
  124         struct resource *r, *s;
  125 
  126         DPRINTF(("rman_manage_region: <%s> request: start %#lx, end %#lx\n",
  127             rm->rm_descr, start, end));
  128         r = malloc(sizeof *r, M_RMAN, M_NOWAIT | M_ZERO);
  129         if (r == 0)
  130                 return ENOMEM;
  131         r->r_start = start;
  132         r->r_end = end;
  133         r->r_rm = rm;
  134 
  135         mtx_lock(rm->rm_mtx);
  136         for (s = TAILQ_FIRST(&rm->rm_list);     
  137              s && s->r_end < r->r_start;
  138              s = TAILQ_NEXT(s, r_link))
  139                 ;
  140 
  141         if (s == NULL) {
  142                 TAILQ_INSERT_TAIL(&rm->rm_list, r, r_link);
  143         } else {
  144                 TAILQ_INSERT_BEFORE(s, r, r_link);
  145         }
  146 
  147         mtx_unlock(rm->rm_mtx);
  148         return 0;
  149 }
  150 
  151 int
  152 rman_fini(struct rman *rm)
  153 {
  154         struct resource *r;
  155 
  156         mtx_lock(rm->rm_mtx);
  157         TAILQ_FOREACH(r, &rm->rm_list, r_link) {
  158                 if (r->r_flags & RF_ALLOCATED) {
  159                         mtx_unlock(rm->rm_mtx);
  160                         return EBUSY;
  161                 }
  162         }
  163 
  164         /*
  165          * There really should only be one of these if we are in this
  166          * state and the code is working properly, but it can't hurt.
  167          */
  168         while (!TAILQ_EMPTY(&rm->rm_list)) {
  169                 r = TAILQ_FIRST(&rm->rm_list);
  170                 TAILQ_REMOVE(&rm->rm_list, r, r_link);
  171                 free(r, M_RMAN);
  172         }
  173         mtx_unlock(rm->rm_mtx);
  174         mtx_lock(&rman_mtx);
  175         TAILQ_REMOVE(&rman_head, rm, rm_link);
  176         mtx_unlock(&rman_mtx);
  177         mtx_destroy(rm->rm_mtx);
  178         free(rm->rm_mtx, M_RMAN);
  179 
  180         return 0;
  181 }
  182 
  183 struct resource *
  184 rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
  185                       u_long count, u_long bound,  u_int flags,
  186                       struct device *dev)
  187 {
  188         u_int   want_activate;
  189         struct  resource *r, *s, *rv;
  190         u_long  rstart, rend, amask, bmask;
  191 
  192         rv = 0;
  193 
  194         DPRINTF(("rman_reserve_resource: <%s> request: [%#lx, %#lx], length "
  195                "%#lx, flags %u, device %s\n", rm->rm_descr, start, end, count,
  196                flags, dev == NULL ? "<null>" : device_get_nameunit(dev)));
  197         want_activate = (flags & RF_ACTIVE);
  198         flags &= ~RF_ACTIVE;
  199 
  200         mtx_lock(rm->rm_mtx);
  201 
  202         for (r = TAILQ_FIRST(&rm->rm_list); 
  203              r && r->r_end < start;
  204              r = TAILQ_NEXT(r, r_link))
  205                 ;
  206 
  207         if (r == NULL) {
  208                 DPRINTF(("could not find a region\n"));
  209                 goto out;
  210         }
  211 
  212         amask = (1ul << RF_ALIGNMENT(flags)) - 1;
  213         /* If bound is 0, bmask will also be 0 */
  214         bmask = ~(bound - 1);
  215         /*
  216          * First try to find an acceptable totally-unshared region.
  217          */
  218         for (s = r; s; s = TAILQ_NEXT(s, r_link)) {
  219                 DPRINTF(("considering [%#lx, %#lx]\n", s->r_start, s->r_end));
  220                 if (s->r_start > end) {
  221                         DPRINTF(("s->r_start (%#lx) > end (%#lx)\n", s->r_start, end));
  222                         break;
  223                 }
  224                 if (s->r_flags & RF_ALLOCATED) {
  225                         DPRINTF(("region is allocated\n"));
  226                         continue;
  227                 }
  228                 rstart = ulmax(s->r_start, start);
  229                 /*
  230                  * Try to find a region by adjusting to boundary and alignment
  231                  * until both conditions are satisfied. This is not an optimal
  232                  * algorithm, but in most cases it isn't really bad, either.
  233                  */
  234                 do {
  235                         rstart = (rstart + amask) & ~amask;
  236                         if (((rstart ^ (rstart + count - 1)) & bmask) != 0)
  237                                 rstart += bound - (rstart & ~bmask);
  238                 } while ((rstart & amask) != 0 && rstart < end &&
  239                     rstart < s->r_end);
  240                 rend = ulmin(s->r_end, ulmax(rstart + count - 1, end));
  241                 if (rstart > rend) {
  242                         DPRINTF(("adjusted start exceeds end\n"));
  243                         continue;
  244                 }
  245                 DPRINTF(("truncated region: [%#lx, %#lx]; size %#lx (requested %#lx)\n",
  246                        rstart, rend, (rend - rstart + 1), count));
  247 
  248                 if ((rend - rstart + 1) >= count) {
  249                         DPRINTF(("candidate region: [%#lx, %#lx], size %#lx\n",
  250                                rend, rstart, (rend - rstart + 1)));
  251                         if ((s->r_end - s->r_start + 1) == count) {
  252                                 DPRINTF(("candidate region is entire chunk\n"));
  253                                 rv = s;
  254                                 rv->r_flags |= RF_ALLOCATED | flags;
  255                                 rv->r_dev = dev;
  256                                 goto out;
  257                         }
  258 
  259                         /*
  260                          * If s->r_start < rstart and
  261                          *    s->r_end > rstart + count - 1, then
  262                          * we need to split the region into three pieces
  263                          * (the middle one will get returned to the user).
  264                          * Otherwise, we are allocating at either the
  265                          * beginning or the end of s, so we only need to
  266                          * split it in two.  The first case requires
  267                          * two new allocations; the second requires but one.
  268                          */
  269                         rv = malloc(sizeof *rv, M_RMAN, M_NOWAIT | M_ZERO);
  270                         if (rv == 0)
  271                                 goto out;
  272                         rv->r_start = rstart;
  273                         rv->r_end = rstart + count - 1;
  274                         rv->r_flags = flags | RF_ALLOCATED;
  275                         rv->r_dev = dev;
  276                         rv->r_rm = rm;
  277                         
  278                         if (s->r_start < rv->r_start && s->r_end > rv->r_end) {
  279                                 DPRINTF(("splitting region in three parts: "
  280                                        "[%#lx, %#lx]; [%#lx, %#lx]; [%#lx, %#lx]\n",
  281                                        s->r_start, rv->r_start - 1,
  282                                        rv->r_start, rv->r_end,
  283                                        rv->r_end + 1, s->r_end));
  284                                 /*
  285                                  * We are allocating in the middle.
  286                                  */
  287                                 r = malloc(sizeof *r, M_RMAN, M_NOWAIT|M_ZERO);
  288                                 if (r == 0) {
  289                                         free(rv, M_RMAN);
  290                                         rv = 0;
  291                                         goto out;
  292                                 }
  293                                 r->r_start = rv->r_end + 1;
  294                                 r->r_end = s->r_end;
  295                                 r->r_flags = s->r_flags;
  296                                 r->r_rm = rm;
  297                                 s->r_end = rv->r_start - 1;
  298                                 TAILQ_INSERT_AFTER(&rm->rm_list, s, rv,
  299                                                      r_link);
  300                                 TAILQ_INSERT_AFTER(&rm->rm_list, rv, r,
  301                                                      r_link);
  302                         } else if (s->r_start == rv->r_start) {
  303                                 DPRINTF(("allocating from the beginning\n"));
  304                                 /*
  305                                  * We are allocating at the beginning.
  306                                  */
  307                                 s->r_start = rv->r_end + 1;
  308                                 TAILQ_INSERT_BEFORE(s, rv, r_link);
  309                         } else {
  310                                 DPRINTF(("allocating at the end\n"));
  311                                 /*
  312                                  * We are allocating at the end.
  313                                  */
  314                                 s->r_end = rv->r_start - 1;
  315                                 TAILQ_INSERT_AFTER(&rm->rm_list, s, rv,
  316                                                      r_link);
  317                         }
  318                         goto out;
  319                 }
  320         }
  321 
  322         /*
  323          * Now find an acceptable shared region, if the client's requirements
  324          * allow sharing.  By our implementation restriction, a candidate
  325          * region must match exactly by both size and sharing type in order
  326          * to be considered compatible with the client's request.  (The
  327          * former restriction could probably be lifted without too much
  328          * additional work, but this does not seem warranted.)
  329          */
  330         DPRINTF(("no unshared regions found\n"));
  331         if ((flags & (RF_SHAREABLE | RF_TIMESHARE)) == 0)
  332                 goto out;
  333 
  334         for (s = r; s; s = TAILQ_NEXT(s, r_link)) {
  335                 if (s->r_start > end)
  336                         break;
  337                 if ((s->r_flags & flags) != flags)
  338                         continue;
  339                 rstart = ulmax(s->r_start, start);
  340                 rend = ulmin(s->r_end, ulmax(start + count - 1, end));
  341                 if (s->r_start >= start && s->r_end <= end
  342                     && (s->r_end - s->r_start + 1) == count &&
  343                     (s->r_start & amask) == 0 &&
  344                     ((s->r_start ^ s->r_end) & bmask) == 0) {
  345                         rv = malloc(sizeof *rv, M_RMAN, M_NOWAIT | M_ZERO);
  346                         if (rv == 0)
  347                                 goto out;
  348                         rv->r_start = s->r_start;
  349                         rv->r_end = s->r_end;
  350                         rv->r_flags = s->r_flags & 
  351                                 (RF_ALLOCATED | RF_SHAREABLE | RF_TIMESHARE);
  352                         rv->r_dev = dev;
  353                         rv->r_rm = rm;
  354                         if (s->r_sharehead == 0) {
  355                                 s->r_sharehead = malloc(sizeof *s->r_sharehead,
  356                                                 M_RMAN, M_NOWAIT | M_ZERO);
  357                                 if (s->r_sharehead == 0) {
  358                                         free(rv, M_RMAN);
  359                                         rv = 0;
  360                                         goto out;
  361                                 }
  362                                 LIST_INIT(s->r_sharehead);
  363                                 LIST_INSERT_HEAD(s->r_sharehead, s, 
  364                                                  r_sharelink);
  365                                 s->r_flags |= RF_FIRSTSHARE;
  366                         }
  367                         rv->r_sharehead = s->r_sharehead;
  368                         LIST_INSERT_HEAD(s->r_sharehead, rv, r_sharelink);
  369                         goto out;
  370                 }
  371         }
  372 
  373         /*
  374          * We couldn't find anything.
  375          */
  376 out:
  377         /*
  378          * If the user specified RF_ACTIVE in the initial flags,
  379          * which is reflected in `want_activate', we attempt to atomically
  380          * activate the resource.  If this fails, we release the resource
  381          * and indicate overall failure.  (This behavior probably doesn't
  382          * make sense for RF_TIMESHARE-type resources.)
  383          */
  384         if (rv && want_activate) {
  385                 struct resource *whohas;
  386                 if (int_rman_activate_resource(rm, rv, &whohas)) {
  387                         int_rman_release_resource(rm, rv);
  388                         rv = 0;
  389                 }
  390         }
  391                         
  392         mtx_unlock(rm->rm_mtx);
  393         return (rv);
  394 }
  395 
  396 struct resource *
  397 rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count,
  398                       u_int flags, struct device *dev)
  399 {
  400 
  401         return (rman_reserve_resource_bound(rm, start, end, count, 0, flags,
  402             dev));
  403 }
  404 
  405 static int
  406 int_rman_activate_resource(struct rman *rm, struct resource *r,
  407                            struct resource **whohas)
  408 {
  409         struct resource *s;
  410         int ok;
  411 
  412         /*
  413          * If we are not timesharing, then there is nothing much to do.
  414          * If we already have the resource, then there is nothing at all to do.
  415          * If we are not on a sharing list with anybody else, then there is
  416          * little to do.
  417          */
  418         if ((r->r_flags & RF_TIMESHARE) == 0
  419             || (r->r_flags & RF_ACTIVE) != 0
  420             || r->r_sharehead == 0) {
  421                 r->r_flags |= RF_ACTIVE;
  422                 return 0;
  423         }
  424 
  425         ok = 1;
  426         for (s = LIST_FIRST(r->r_sharehead); s && ok;
  427              s = LIST_NEXT(s, r_sharelink)) {
  428                 if ((s->r_flags & RF_ACTIVE) != 0) {
  429                         ok = 0;
  430                         *whohas = s;
  431                 }
  432         }
  433         if (ok) {
  434                 r->r_flags |= RF_ACTIVE;
  435                 return 0;
  436         }
  437         return EBUSY;
  438 }
  439 
  440 int
  441 rman_activate_resource(struct resource *r)
  442 {
  443         int rv;
  444         struct resource *whohas;
  445         struct rman *rm;
  446 
  447         rm = r->r_rm;
  448         mtx_lock(rm->rm_mtx);
  449         rv = int_rman_activate_resource(rm, r, &whohas);
  450         mtx_unlock(rm->rm_mtx);
  451         return rv;
  452 }
  453 
  454 int
  455 rman_await_resource(struct resource *r, int pri, int timo)
  456 {
  457         int     rv;
  458         struct  resource *whohas;
  459         struct  rman *rm;
  460 
  461         rm = r->r_rm;
  462         mtx_lock(rm->rm_mtx);
  463         for (;;) {
  464                 rv = int_rman_activate_resource(rm, r, &whohas);
  465                 if (rv != EBUSY)
  466                         return (rv);    /* returns with mutex held */
  467 
  468                 if (r->r_sharehead == 0)
  469                         panic("rman_await_resource");
  470                 whohas->r_flags |= RF_WANTED;
  471                 rv = msleep(r->r_sharehead, rm->rm_mtx, pri, "rmwait", timo);
  472                 if (rv) {
  473                         mtx_unlock(rm->rm_mtx);
  474                         return (rv);
  475                 }
  476         }
  477 }
  478 
  479 static int
  480 int_rman_deactivate_resource(struct resource *r)
  481 {
  482 
  483         r->r_flags &= ~RF_ACTIVE;
  484         if (r->r_flags & RF_WANTED) {
  485                 r->r_flags &= ~RF_WANTED;
  486                 wakeup(r->r_sharehead);
  487         }
  488         return 0;
  489 }
  490 
  491 int
  492 rman_deactivate_resource(struct resource *r)
  493 {
  494         struct  rman *rm;
  495 
  496         rm = r->r_rm;
  497         mtx_lock(rm->rm_mtx);
  498         int_rman_deactivate_resource(r);
  499         mtx_unlock(rm->rm_mtx);
  500         return 0;
  501 }
  502 
  503 static int
  504 int_rman_release_resource(struct rman *rm, struct resource *r)
  505 {
  506         struct  resource *s, *t;
  507 
  508         if (r->r_flags & RF_ACTIVE)
  509                 int_rman_deactivate_resource(r);
  510 
  511         /*
  512          * Check for a sharing list first.  If there is one, then we don't
  513          * have to think as hard.
  514          */
  515         if (r->r_sharehead) {
  516                 /*
  517                  * If a sharing list exists, then we know there are at
  518                  * least two sharers.
  519                  *
  520                  * If we are in the main circleq, appoint someone else.
  521                  */
  522                 LIST_REMOVE(r, r_sharelink);
  523                 s = LIST_FIRST(r->r_sharehead);
  524                 if (r->r_flags & RF_FIRSTSHARE) {
  525                         s->r_flags |= RF_FIRSTSHARE;
  526                         TAILQ_INSERT_BEFORE(r, s, r_link);
  527                         TAILQ_REMOVE(&rm->rm_list, r, r_link);
  528                 }
  529 
  530                 /*
  531                  * Make sure that the sharing list goes away completely
  532                  * if the resource is no longer being shared at all.
  533                  */
  534                 if (LIST_NEXT(s, r_sharelink) == 0) {
  535                         free(s->r_sharehead, M_RMAN);
  536                         s->r_sharehead = 0;
  537                         s->r_flags &= ~RF_FIRSTSHARE;
  538                 }
  539                 goto out;
  540         }
  541 
  542         /*
  543          * Look at the adjacent resources in the list and see if our
  544          * segment can be merged with any of them.  If either of the
  545          * resources is allocated or is not exactly adjacent then they
  546          * cannot be merged with our segment.
  547          */
  548         s = TAILQ_PREV(r, resource_head, r_link);
  549         if (s != NULL && ((s->r_flags & RF_ALLOCATED) != 0 ||
  550             s->r_end + 1 != r->r_start))
  551                 s = NULL;
  552         t = TAILQ_NEXT(r, r_link);
  553         if (t != NULL && ((t->r_flags & RF_ALLOCATED) != 0 ||
  554             r->r_end + 1 != t->r_start))
  555                 t = NULL;
  556 
  557         if (s != NULL && t != NULL) {
  558                 /*
  559                  * Merge all three segments.
  560                  */
  561                 s->r_end = t->r_end;
  562                 TAILQ_REMOVE(&rm->rm_list, r, r_link);
  563                 TAILQ_REMOVE(&rm->rm_list, t, r_link);
  564                 free(t, M_RMAN);
  565         } else if (s != NULL) {
  566                 /*
  567                  * Merge previous segment with ours.
  568                  */
  569                 s->r_end = r->r_end;
  570                 TAILQ_REMOVE(&rm->rm_list, r, r_link);
  571         } else if (t != NULL) {
  572                 /*
  573                  * Merge next segment with ours.
  574                  */
  575                 t->r_start = r->r_start;
  576                 TAILQ_REMOVE(&rm->rm_list, r, r_link);
  577         } else {
  578                 /*
  579                  * At this point, we know there is nothing we
  580                  * can potentially merge with, because on each
  581                  * side, there is either nothing there or what is
  582                  * there is still allocated.  In that case, we don't
  583                  * want to remove r from the list; we simply want to
  584                  * change it to an unallocated region and return
  585                  * without freeing anything.
  586                  */
  587                 r->r_flags &= ~RF_ALLOCATED;
  588                 return 0;
  589         }
  590 
  591 out:
  592         free(r, M_RMAN);
  593         return 0;
  594 }
  595 
  596 int
  597 rman_release_resource(struct resource *r)
  598 {
  599         int     rv;
  600         struct  rman *rm = r->r_rm;
  601 
  602         mtx_lock(rm->rm_mtx);
  603         rv = int_rman_release_resource(rm, r);
  604         mtx_unlock(rm->rm_mtx);
  605         return (rv);
  606 }
  607 
  608 uint32_t
  609 rman_make_alignment_flags(uint32_t size)
  610 {
  611         int     i;
  612 
  613         /*
  614          * Find the hightest bit set, and add one if more than one bit
  615          * set.  We're effectively computing the ceil(log2(size)) here.
  616          */
  617         for (i = 31; i > 0; i--)
  618                 if ((1 << i) & size)
  619                         break;
  620         if (~(1 << i) & size)
  621                 i++;
  622 
  623         return(RF_ALIGNMENT_LOG2(i));
  624 }
  625 
  626 u_long
  627 rman_get_start(struct resource *r)
  628 {
  629         return (r->r_start);
  630 }
  631 
  632 u_long
  633 rman_get_end(struct resource *r)
  634 {
  635         return (r->r_end);
  636 }
  637 
  638 u_long
  639 rman_get_size(struct resource *r)
  640 {
  641         return (r->r_end - r->r_start + 1);
  642 }
  643 
  644 u_int
  645 rman_get_flags(struct resource *r)
  646 {
  647         return (r->r_flags);
  648 }
  649 
  650 void
  651 rman_set_virtual(struct resource *r, void *v)
  652 {
  653         r->r_virtual = v;
  654 }
  655 
  656 void *
  657 rman_get_virtual(struct resource *r)
  658 {
  659         return (r->r_virtual);
  660 }
  661 
  662 void
  663 rman_set_bustag(struct resource *r, bus_space_tag_t t)
  664 {
  665         r->r_bustag = t;
  666 }
  667 
  668 bus_space_tag_t
  669 rman_get_bustag(struct resource *r)
  670 {
  671         return (r->r_bustag);
  672 }
  673 
  674 void
  675 rman_set_bushandle(struct resource *r, bus_space_handle_t h)
  676 {
  677         r->r_bushandle = h;
  678 }
  679 
  680 bus_space_handle_t
  681 rman_get_bushandle(struct resource *r)
  682 {
  683         return (r->r_bushandle);
  684 }
  685 
  686 void
  687 rman_set_rid(struct resource *r, int rid)
  688 {
  689         r->r_rid = rid;
  690 }
  691 
  692 void
  693 rman_set_start(struct resource *r, u_long start)
  694 {
  695         r->r_start = start;
  696 }
  697 
  698 void
  699 rman_set_end(struct resource *r, u_long end)
  700 {
  701         r->r_end = end;
  702 }
  703 
  704 int
  705 rman_get_rid(struct resource *r)
  706 {
  707         return (r->r_rid);
  708 }
  709 
  710 struct device *
  711 rman_get_device(struct resource *r)
  712 {
  713         return (r->r_dev);
  714 }

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