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


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/geom/geom_subr.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (c) 2002 Poul-Henning Kamp
    3  * Copyright (c) 2002 Networks Associates Technology, Inc.
    4  * All rights reserved.
    5  *
    6  * This software was developed for the FreeBSD Project by Poul-Henning Kamp
    7  * and NAI Labs, the Security Research Division of Network Associates, Inc.
    8  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
    9  * DARPA CHATS research program.
   10  *
   11  * Redistribution and use in source and binary forms, with or without
   12  * modification, are permitted provided that the following conditions
   13  * are met:
   14  * 1. Redistributions of source code must retain the above copyright
   15  *    notice, this list of conditions and the following disclaimer.
   16  * 2. Redistributions in binary form must reproduce the above copyright
   17  *    notice, this list of conditions and the following disclaimer in the
   18  *    documentation and/or other materials provided with the distribution.
   19  * 3. The names of the authors may not be used to endorse or promote
   20  *    products derived from this software without specific prior written
   21  *    permission.
   22  *
   23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   33  * SUCH DAMAGE.
   34  *
   35  * $FreeBSD: releng/5.1/sys/geom/geom_subr.c 114511 2003-05-02 06:42:59Z phk $
   36  */
   37 
   38 
   39 #include <sys/param.h>
   40 #include <sys/systm.h>
   41 #include <sys/devicestat.h>
   42 #include <sys/kernel.h>
   43 #include <sys/malloc.h>
   44 #include <sys/bio.h>
   45 #include <sys/sysctl.h>
   46 #include <sys/proc.h>
   47 #include <sys/kthread.h>
   48 #include <sys/lock.h>
   49 #include <sys/mutex.h>
   50 #include <sys/errno.h>
   51 #include <sys/sbuf.h>
   52 #include <geom/geom.h>
   53 #include <geom/geom_int.h>
   54 #include <machine/stdarg.h>
   55 
   56 struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes);
   57 static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms);
   58 static int g_nproviders;
   59 char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim;
   60 
   61 static int g_ignition;
   62 
   63 
   64 /*
   65  * This event offers a new class a chance to taste all preexisting providers.
   66  */
   67 static void
   68 g_new_class_event(void *arg, int flag)
   69 {
   70         struct g_class *mp2, *mp;
   71         struct g_geom *gp;
   72         struct g_provider *pp;
   73 
   74         g_topology_assert();
   75         if (flag == EV_CANCEL)
   76                 return;
   77         if (g_shutdown)
   78                 return;
   79         mp2 = arg;
   80         if (mp2->taste == NULL)
   81                 return;
   82         LIST_FOREACH(mp, &g_classes, class) {
   83                 if (mp2 == mp)
   84                         continue;
   85                 LIST_FOREACH(gp, &mp->geom, geom) {
   86                         LIST_FOREACH(pp, &gp->provider, provider) {
   87                                 mp2->taste(mp2, pp, 0);
   88                                 g_topology_assert();
   89                         }
   90                 }
   91         }
   92 }
   93 
   94 void
   95 g_add_class(struct g_class *mp)
   96 {
   97 
   98         if (!g_ignition) {
   99                 g_ignition++;
  100                 g_init();
  101         }
  102         mp->protect = 0x020016600;
  103         g_topology_lock();
  104         g_trace(G_T_TOPOLOGY, "g_add_class(%s)", mp->name);
  105         LIST_INIT(&mp->geom);
  106         LIST_INSERT_HEAD(&g_classes, mp, class);
  107         if (g_nproviders > 0 && mp->taste != NULL)
  108                 g_post_event(g_new_class_event, mp, M_WAITOK, mp, NULL);
  109         g_topology_unlock();
  110 }
  111 
  112 struct g_geom *
  113 g_new_geomf(struct g_class *mp, const char *fmt, ...)
  114 {
  115         struct g_geom *gp;
  116         va_list ap;
  117         struct sbuf *sb;
  118 
  119         g_topology_assert();
  120         va_start(ap, fmt);
  121         sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
  122         sbuf_vprintf(sb, fmt, ap);
  123         sbuf_finish(sb);
  124         gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO);
  125         gp->protect = 0x020016601;
  126         gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
  127         gp->class = mp;
  128         gp->rank = 1;
  129         LIST_INIT(&gp->consumer);
  130         LIST_INIT(&gp->provider);
  131         LIST_INSERT_HEAD(&mp->geom, gp, geom);
  132         TAILQ_INSERT_HEAD(&geoms, gp, geoms);
  133         strcpy(gp->name, sbuf_data(sb));
  134         sbuf_delete(sb);
  135         return (gp);
  136 }
  137 
  138 void
  139 g_destroy_geom(struct g_geom *gp)
  140 {
  141 
  142         g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name);
  143         g_topology_assert();
  144         KASSERT(LIST_EMPTY(&gp->consumer),
  145             ("g_destroy_geom(%s) with consumer(s) [%p]",
  146             gp->name, LIST_FIRST(&gp->consumer)));
  147         KASSERT(LIST_EMPTY(&gp->provider),
  148             ("g_destroy_geom(%s) with provider(s) [%p]",
  149             gp->name, LIST_FIRST(&gp->consumer)));
  150         g_cancel_event(gp);
  151         LIST_REMOVE(gp, geom);
  152         TAILQ_REMOVE(&geoms, gp, geoms);
  153         g_free(gp->name);
  154         g_free(gp);
  155 }
  156 
  157 /*
  158  * This function is called (repeatedly) until has withered away.
  159  */
  160 void
  161 g_wither_geom(struct g_geom *gp, int error)
  162 {
  163         struct g_provider *pp, *pp2;
  164         struct g_consumer *cp, *cp2;
  165         static int once_is_enough;
  166 
  167         if (once_is_enough)
  168                 return;
  169         once_is_enough = 1;
  170         g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name);
  171         g_topology_assert();
  172         if (!(gp->flags & G_GEOM_WITHER)) {
  173                 gp->flags |= G_GEOM_WITHER;
  174                 LIST_FOREACH(pp, &gp->provider, provider)
  175                         g_orphan_provider(pp, error);
  176         }
  177         for (pp = LIST_FIRST(&gp->provider); pp != NULL; pp = pp2) {
  178                 pp2 = LIST_NEXT(pp, provider);
  179                 if (!LIST_EMPTY(&pp->consumers))
  180                         continue;
  181                 g_destroy_provider(pp);
  182         }
  183         for (cp = LIST_FIRST(&gp->consumer); cp != NULL; cp = cp2) {
  184                 cp2 = LIST_NEXT(cp, consumer);
  185                 if (cp->acr || cp->acw || cp->ace)
  186                         continue;
  187                 g_detach(cp);
  188                 g_destroy_consumer(cp);
  189         }
  190         if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
  191                 g_destroy_geom(gp);
  192         once_is_enough = 0;
  193 }
  194 
  195 struct g_consumer *
  196 g_new_consumer(struct g_geom *gp)
  197 {
  198         struct g_consumer *cp;
  199 
  200         g_topology_assert();
  201         KASSERT(gp->orphan != NULL,
  202             ("g_new_consumer on geom(%s) (class %s) without orphan",
  203             gp->name, gp->class->name));
  204 
  205         cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO);
  206         cp->protect = 0x020016602;
  207         cp->geom = gp;
  208         cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED,
  209             DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
  210         LIST_INSERT_HEAD(&gp->consumer, cp, consumer);
  211         return(cp);
  212 }
  213 
  214 void
  215 g_destroy_consumer(struct g_consumer *cp)
  216 {
  217         struct g_geom *gp;
  218 
  219         g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp);
  220         g_topology_assert();
  221         KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached"));
  222         KASSERT (cp->acr == 0, ("g_destroy_consumer with acr"));
  223         KASSERT (cp->acw == 0, ("g_destroy_consumer with acw"));
  224         KASSERT (cp->ace == 0, ("g_destroy_consumer with ace"));
  225         g_cancel_event(cp);
  226         gp = cp->geom;
  227         LIST_REMOVE(cp, consumer);
  228         devstat_remove_entry(cp->stat);
  229         g_free(cp);
  230         if (gp->flags & G_GEOM_WITHER)
  231                 g_wither_geom(gp, 0);
  232 }
  233 
  234 static void
  235 g_new_provider_event(void *arg, int flag)
  236 {
  237         struct g_class *mp;
  238         struct g_provider *pp;
  239         struct g_consumer *cp;
  240         int i;
  241 
  242         g_topology_assert();
  243         if (flag == EV_CANCEL)
  244                 return;
  245         if (g_shutdown)
  246                 return;
  247         pp = arg;
  248         LIST_FOREACH(mp, &g_classes, class) {
  249                 if (mp->taste == NULL)
  250                         continue;
  251                 i = 1;
  252                 LIST_FOREACH(cp, &pp->consumers, consumers)
  253                         if (cp->geom->class == mp)
  254                                 i = 0;
  255                 if (!i)
  256                         continue;
  257                 mp->taste(mp, pp, 0);
  258                 g_topology_assert();
  259         }
  260 }
  261 
  262 
  263 struct g_provider *
  264 g_new_providerf(struct g_geom *gp, const char *fmt, ...)
  265 {
  266         struct g_provider *pp;
  267         struct sbuf *sb;
  268         va_list ap;
  269 
  270         g_topology_assert();
  271         va_start(ap, fmt);
  272         sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
  273         sbuf_vprintf(sb, fmt, ap);
  274         sbuf_finish(sb);
  275         pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
  276         pp->protect = 0x020016603;
  277         pp->name = (char *)(pp + 1);
  278         strcpy(pp->name, sbuf_data(sb));
  279         sbuf_delete(sb);
  280         LIST_INIT(&pp->consumers);
  281         pp->error = ENXIO;
  282         pp->geom = gp;
  283         pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED,
  284             DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
  285         LIST_INSERT_HEAD(&gp->provider, pp, provider);
  286         g_nproviders++;
  287         g_post_event(g_new_provider_event, pp, M_WAITOK, pp, NULL);
  288         return (pp);
  289 }
  290 
  291 void
  292 g_error_provider(struct g_provider *pp, int error)
  293 {
  294 
  295         pp->error = error;
  296 }
  297 
  298 
  299 void
  300 g_destroy_provider(struct g_provider *pp)
  301 {
  302         struct g_geom *gp;
  303 
  304         g_topology_assert();
  305         KASSERT(LIST_EMPTY(&pp->consumers),
  306             ("g_destroy_provider but attached"));
  307         KASSERT (pp->acr == 0, ("g_destroy_provider with acr"));
  308         KASSERT (pp->acw == 0, ("g_destroy_provider with acw"));
  309         KASSERT (pp->acw == 0, ("g_destroy_provider with ace"));
  310         g_cancel_event(pp);
  311         g_nproviders--;
  312         LIST_REMOVE(pp, provider);
  313         gp = pp->geom;
  314         devstat_remove_entry(pp->stat);
  315         g_free(pp);
  316         if ((gp->flags & G_GEOM_WITHER))
  317                 g_wither_geom(gp, 0);
  318 }
  319 
  320 /*
  321  * We keep the "geoms" list sorted by topological order (== increasing
  322  * numerical rank) at all times.
  323  * When an attach is done, the attaching geoms rank is invalidated
  324  * and it is moved to the tail of the list.
  325  * All geoms later in the sequence has their ranks reevaluated in
  326  * sequence.  If we cannot assign rank to a geom because it's
  327  * prerequisites do not have rank, we move that element to the tail
  328  * of the sequence with invalid rank as well.
  329  * At some point we encounter our original geom and if we stil fail
  330  * to assign it a rank, there must be a loop and we fail back to
  331  * g_attach() which detach again and calls redo_rank again
  332  * to fix up the damage.
  333  * It would be much simpler code wise to do it recursively, but we
  334  * can't risk that on the kernel stack.
  335  */
  336 
  337 static int
  338 redo_rank(struct g_geom *gp)
  339 {
  340         struct g_consumer *cp;
  341         struct g_geom *gp1, *gp2;
  342         int n, m;
  343 
  344         g_topology_assert();
  345 
  346         /* Invalidate this geoms rank and move it to the tail */
  347         gp1 = TAILQ_NEXT(gp, geoms);
  348         if (gp1 != NULL) {
  349                 gp->rank = 0;
  350                 TAILQ_REMOVE(&geoms, gp, geoms);
  351                 TAILQ_INSERT_TAIL(&geoms, gp, geoms);
  352         } else {
  353                 gp1 = gp;
  354         }
  355 
  356         /* re-rank the rest of the sequence */
  357         for (; gp1 != NULL; gp1 = gp2) {
  358                 gp1->rank = 0;
  359                 m = 1;
  360                 LIST_FOREACH(cp, &gp1->consumer, consumer) {
  361                         if (cp->provider == NULL)
  362                                 continue;
  363                         n = cp->provider->geom->rank;
  364                         if (n == 0) {
  365                                 m = 0;
  366                                 break;
  367                         } else if (n >= m)
  368                                 m = n + 1;
  369                 }
  370                 gp1->rank = m;
  371                 gp2 = TAILQ_NEXT(gp1, geoms);
  372 
  373                 /* got a rank, moving on */
  374                 if (m != 0)
  375                         continue;
  376 
  377                 /* no rank to original geom means loop */
  378                 if (gp == gp1) 
  379                         return (ELOOP);
  380 
  381                 /* no rank, put it at the end move on */
  382                 TAILQ_REMOVE(&geoms, gp1, geoms);
  383                 TAILQ_INSERT_TAIL(&geoms, gp1, geoms);
  384         }
  385         return (0);
  386 }
  387 
  388 int
  389 g_attach(struct g_consumer *cp, struct g_provider *pp)
  390 {
  391         int error;
  392 
  393         g_topology_assert();
  394         KASSERT(cp->provider == NULL, ("attach but attached"));
  395         cp->provider = pp;
  396         LIST_INSERT_HEAD(&pp->consumers, cp, consumers);
  397         error = redo_rank(cp->geom);
  398         if (error) {
  399                 LIST_REMOVE(cp, consumers);
  400                 cp->provider = NULL;
  401                 redo_rank(cp->geom);
  402         }
  403         return (error);
  404 }
  405 
  406 void
  407 g_detach(struct g_consumer *cp)
  408 {
  409         struct g_provider *pp;
  410 
  411         g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp);
  412         KASSERT(cp != (void*)0xd0d0d0d0, ("ARGH!"));
  413         g_topology_assert();
  414         KASSERT(cp->provider != NULL, ("detach but not attached"));
  415         KASSERT(cp->acr == 0, ("detach but nonzero acr"));
  416         KASSERT(cp->acw == 0, ("detach but nonzero acw"));
  417         KASSERT(cp->ace == 0, ("detach but nonzero ace"));
  418         KASSERT(cp->nstart == cp->nend,
  419             ("detach with active requests"));
  420         pp = cp->provider;
  421         LIST_REMOVE(cp, consumers);
  422         cp->provider = NULL;
  423         if (pp->geom->flags & G_GEOM_WITHER)
  424                 g_wither_geom(pp->geom, 0);
  425         redo_rank(cp->geom);
  426 }
  427 
  428 
  429 /*
  430  * g_access_abs()
  431  *
  432  * Access-check with absolute new values:  Just fall through
  433  * and use the relative version.
  434  */
  435 int
  436 g_access_abs(struct g_consumer *cp, int acr, int acw, int ace)
  437 {
  438 
  439         g_topology_assert();
  440         return(g_access_rel(cp,
  441                 acr - cp->acr,
  442                 acw - cp->acw,
  443                 ace - cp->ace));
  444 }
  445 
  446 /*
  447  * g_access_rel()
  448  *
  449  * Access-check with delta values.  The question asked is "can provider
  450  * "cp" change the access counters by the relative amounts dc[rwe] ?"
  451  */
  452 
  453 int
  454 g_access_rel(struct g_consumer *cp, int dcr, int dcw, int dce)
  455 {
  456         struct g_provider *pp;
  457         int pr,pw,pe;
  458         int error;
  459 
  460         pp = cp->provider;
  461 
  462         g_trace(G_T_ACCESS, "g_access_rel(%p(%s), %d, %d, %d)",
  463             cp, pp->name, dcr, dcw, dce);
  464 
  465         g_topology_assert();
  466         KASSERT(cp->provider != NULL, ("access but not attached"));
  467         KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr"));
  468         KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw"));
  469         KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace"));
  470         KASSERT(pp->geom->access != NULL, ("NULL geom->access"));
  471 
  472         /*
  473          * If our class cares about being spoiled, and we have been, we
  474          * are probably just ahead of the event telling us that.  Fail
  475          * now rather than having to unravel this later.
  476          */
  477         if (cp->geom->spoiled != NULL && cp->spoiled) {
  478                 KASSERT(dcr <= 0, ("spoiled but dcr = %d", dcr));
  479                 KASSERT(dcw <= 0, ("spoiled but dce = %d", dcw));
  480                 KASSERT(dce <= 0, ("spoiled but dcw = %d", dce));
  481         }
  482 
  483         /*
  484          * Figure out what counts the provider would have had, if this
  485          * consumer had (r0w0e0) at this time.
  486          */
  487         pr = pp->acr - cp->acr;
  488         pw = pp->acw - cp->acw;
  489         pe = pp->ace - cp->ace;
  490 
  491         g_trace(G_T_ACCESS,
  492     "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)",
  493             dcr, dcw, dce,
  494             cp->acr, cp->acw, cp->ace,
  495             pp->acr, pp->acw, pp->ace,
  496             pp, pp->name);
  497 
  498         /* If foot-shooting is enabled, any open on rank#1 is OK */
  499         if ((g_debugflags & 16) && pp->geom->rank == 1)
  500                 ;
  501         /* If we try exclusive but already write: fail */
  502         else if (dce > 0 && pw > 0)
  503                 return (EPERM);
  504         /* If we try write but already exclusive: fail */
  505         else if (dcw > 0 && pe > 0)
  506                 return (EPERM);
  507         /* If we try to open more but provider is error'ed: fail */
  508         else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0)
  509                 return (pp->error);
  510 
  511         /* Ok then... */
  512 
  513         error = pp->geom->access(pp, dcr, dcw, dce);
  514         if (!error) {
  515                 /*
  516                  * If we open first write, spoil any partner consumers.
  517                  * If we close last write, trigger re-taste.
  518                  */
  519                 if (pp->acw == 0 && dcw != 0)
  520                         g_spoil(pp, cp);
  521                 else if (pp->acw != 0 && pp->acw == -dcw && 
  522                     !(pp->geom->flags & G_GEOM_WITHER))
  523                         g_post_event(g_new_provider_event, pp, M_WAITOK, 
  524                             pp, NULL);
  525 
  526                 pp->acr += dcr;
  527                 pp->acw += dcw;
  528                 pp->ace += dce;
  529                 cp->acr += dcr;
  530                 cp->acw += dcw;
  531                 cp->ace += dce;
  532         }
  533         return (error);
  534 }
  535 
  536 int
  537 g_handleattr_int(struct bio *bp, const char *attribute, int val)
  538 {
  539 
  540         return (g_handleattr(bp, attribute, &val, sizeof val));
  541 }
  542 
  543 int
  544 g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val)
  545 {
  546 
  547         return (g_handleattr(bp, attribute, &val, sizeof val));
  548 }
  549 
  550 int
  551 g_handleattr(struct bio *bp, const char *attribute, void *val, int len)
  552 {
  553         int error;
  554 
  555         if (strcmp(bp->bio_attribute, attribute))
  556                 return (0);
  557         if (bp->bio_length != len) {
  558                 printf("bio_length %jd len %d -> EFAULT\n",
  559                     (intmax_t)bp->bio_length, len);
  560                 error = EFAULT;
  561         } else {
  562                 error = 0;
  563                 bcopy(val, bp->bio_data, len);
  564                 bp->bio_completed = len;
  565         }
  566         g_io_deliver(bp, error);
  567         return (1);
  568 }
  569 
  570 int
  571 g_std_access(struct g_provider *pp __unused,
  572         int dr __unused, int dw __unused, int de __unused)
  573 {
  574 
  575         return (0);
  576 }
  577 
  578 void
  579 g_std_done(struct bio *bp)
  580 {
  581         struct bio *bp2;
  582 
  583         bp2 = bp->bio_parent;
  584         if (bp2->bio_error == 0)
  585                 bp2->bio_error = bp->bio_error;
  586         bp2->bio_completed += bp->bio_completed;
  587         g_destroy_bio(bp);
  588         bp2->bio_inbed++;
  589         if (bp2->bio_children == bp2->bio_inbed)
  590                 g_io_deliver(bp2, bp2->bio_error);
  591 }
  592 
  593 /* XXX: maybe this is only g_slice_spoiled */
  594 
  595 void
  596 g_std_spoiled(struct g_consumer *cp)
  597 {
  598         struct g_geom *gp;
  599         struct g_provider *pp;
  600 
  601         g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp);
  602         g_topology_assert();
  603         g_detach(cp);
  604         gp = cp->geom;
  605         LIST_FOREACH(pp, &gp->provider, provider)
  606                 g_orphan_provider(pp, ENXIO);
  607         g_destroy_consumer(cp);
  608         if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
  609                 g_destroy_geom(gp);
  610         else
  611                 gp->flags |= G_GEOM_WITHER;
  612 }
  613 
  614 /*
  615  * Spoiling happens when a provider is opened for writing, but consumers
  616  * which are configured by in-band data are attached (slicers for instance).
  617  * Since the write might potentially change the in-band data, such consumers
  618  * need to re-evaluate their existence after the writing session closes.
  619  * We do this by (offering to) tear them down when the open for write happens
  620  * in return for a re-taste when it closes again.
  621  * Together with the fact that such consumers grab an 'e' bit whenever they
  622  * are open, regardless of mode, this ends up DTRT.
  623  */
  624 
  625 static void
  626 g_spoil_event(void *arg, int flag)
  627 {
  628         struct g_provider *pp;
  629         struct g_consumer *cp, *cp2;
  630 
  631         g_topology_assert();
  632         if (flag == EV_CANCEL)
  633                 return;
  634         pp = arg;
  635         for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) {
  636                 cp2 = LIST_NEXT(cp, consumers);
  637                 if (!cp->spoiled)
  638                         continue;
  639                 cp->spoiled = 0;
  640                 if (cp->geom->spoiled == NULL)
  641                         continue;
  642                 cp->geom->spoiled(cp);
  643                 g_topology_assert();
  644         }
  645 }
  646 
  647 void
  648 g_spoil(struct g_provider *pp, struct g_consumer *cp)
  649 {
  650         struct g_consumer *cp2;
  651 
  652         g_topology_assert();
  653 
  654         LIST_FOREACH(cp2, &pp->consumers, consumers) {
  655                 if (cp2 == cp)
  656                         continue;
  657 /*
  658                 KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr));
  659                 KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw));
  660 */
  661                 KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace));
  662                 cp2->spoiled++;
  663         }
  664         g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL);
  665 }
  666 
  667 int
  668 g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len)
  669 {
  670         int error, i;
  671 
  672         i = len;
  673         error = g_io_getattr(attr, cp, &i, var);
  674         if (error)
  675                 return (error);
  676         if (i != len)
  677                 return (EINVAL);
  678         return (0);
  679 }
  680 
  681 /*
  682  * Check if the given pointer is a live object
  683  */
  684 
  685 void
  686 g_sanity(void *ptr)
  687 {
  688         struct g_class *mp;
  689         struct g_geom *gp;
  690         struct g_consumer *cp;
  691         struct g_provider *pp;
  692 
  693         if (!(g_debugflags & 0x8))
  694                 return;
  695         LIST_FOREACH(mp, &g_classes, class) {
  696                 KASSERT(mp != ptr, ("Ptr is live class"));
  697                 KASSERT(mp->protect == 0x20016600,
  698                     ("corrupt class %p %x", mp, mp->protect));
  699                 LIST_FOREACH(gp, &mp->geom, geom) {
  700                         KASSERT(gp != ptr, ("Ptr is live geom"));
  701                         KASSERT(gp->protect == 0x20016601,
  702                             ("corrupt geom, %p %x", gp, gp->protect));
  703                         KASSERT(gp->name != ptr, ("Ptr is live geom's name"));
  704                         LIST_FOREACH(cp, &gp->consumer, consumer) {
  705                                 KASSERT(cp != ptr, ("Ptr is live consumer"));
  706                                 KASSERT(cp->protect == 0x20016602,
  707                                     ("corrupt consumer %p %x",
  708                                     cp, cp->protect));
  709                         }
  710                         LIST_FOREACH(pp, &gp->provider, provider) {
  711                                 KASSERT(pp != ptr, ("Ptr is live provider"));
  712                                 KASSERT(pp->protect == 0x20016603,
  713                                     ("corrupt provider %p %x",
  714                                     pp, pp->protect));
  715                         }
  716                 }
  717         }
  718 }
  719 

Cache object: 0ae4df662fdcfe42dd8a3563c0dee7f3


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.