2 * Copyright (c) 2006-2007 Ivan Voras <ivoras@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 /* Implementation notes:
28 * - "Components" are wrappers around providers that make up the
29 * virtual storage (i.e. a virstor has "physical" components)
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/module.h>
40 #include <sys/mutex.h>
43 #include <sys/sysctl.h>
44 #include <sys/malloc.h>
47 #include <sys/kthread.h>
48 #include <sys/mutex.h>
50 #include <geom/geom.h>
52 #include <geom/virstor/g_virstor.h>
53 #include <geom/virstor/g_virstor_md.h>
55 /* Declare malloc(9) label */
56 static MALLOC_DEFINE(M_GVIRSTOR, "gvirstor", "GEOM_VIRSTOR Data");
58 /* GEOM class methods */
59 static g_init_t g_virstor_init;
60 static g_fini_t g_virstor_fini;
61 static g_taste_t g_virstor_taste;
62 static g_ctl_req_t g_virstor_config;
63 static g_ctl_destroy_geom_t g_virstor_destroy_geom;
65 /* Declare & initialize class structure ("geom class") */
66 struct g_class g_virstor_class = {
67 .name = G_VIRSTOR_CLASS_NAME,
69 .init = g_virstor_init,
70 .fini = g_virstor_fini,
71 .taste = g_virstor_taste,
72 .ctlreq = g_virstor_config,
73 .destroy_geom = g_virstor_destroy_geom
74 /* The .dumpconf and the rest are only usable for a geom instance, so
75 * they will be set when such instance is created. */
78 /* Declare sysctl's and loader tunables */
79 SYSCTL_DECL(_kern_geom);
80 SYSCTL_NODE(_kern_geom, OID_AUTO, virstor, CTLFLAG_RW, 0, "GEOM_GVIRSTOR information");
82 static u_int g_virstor_debug = 2; /* XXX: lower to 2 when released to public */
83 TUNABLE_INT("kern.geom.virstor.debug", &g_virstor_debug);
84 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, debug, CTLFLAG_RW, &g_virstor_debug,
85 0, "Debug level (2=production, 5=normal, 15=excessive)");
87 static u_int g_virstor_chunk_watermark = 100;
88 TUNABLE_INT("kern.geom.virstor.chunk_watermark", &g_virstor_chunk_watermark);
89 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, chunk_watermark, CTLFLAG_RW,
90 &g_virstor_chunk_watermark, 0,
91 "Minimum number of free chunks before issuing administrative warning");
93 static u_int g_virstor_component_watermark = 1;
94 TUNABLE_INT("kern.geom.virstor.component_watermark",
95 &g_virstor_component_watermark);
96 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, component_watermark, CTLFLAG_RW,
97 &g_virstor_component_watermark, 0,
98 "Minimum number of free components before issuing administrative warning");
100 static int read_metadata(struct g_consumer *, struct g_virstor_metadata *);
101 static int write_metadata(struct g_consumer *, struct g_virstor_metadata *);
102 static int clear_metadata(struct g_virstor_component *);
103 static int add_provider_to_geom(struct g_virstor_softc *, struct g_provider *,
104 struct g_virstor_metadata *);
105 static struct g_geom *create_virstor_geom(struct g_class *,
106 struct g_virstor_metadata *);
107 static void virstor_check_and_run(struct g_virstor_softc *);
108 static u_int virstor_valid_components(struct g_virstor_softc *);
109 static int virstor_geom_destroy(struct g_virstor_softc *, boolean_t,
111 static void remove_component(struct g_virstor_softc *,
112 struct g_virstor_component *, boolean_t);
113 static void bioq_dismantle(struct bio_queue_head *);
114 static int allocate_chunk(struct g_virstor_softc *,
115 struct g_virstor_component **, u_int *, u_int *);
116 static void delay_destroy_consumer(void *, int);
117 static void dump_component(struct g_virstor_component *comp);
119 static void dump_me(struct virstor_map_entry *me, unsigned int nr);
122 static void virstor_ctl_stop(struct gctl_req *, struct g_class *);
123 static void virstor_ctl_add(struct gctl_req *, struct g_class *);
124 static void virstor_ctl_remove(struct gctl_req *, struct g_class *);
125 static struct g_virstor_softc * virstor_find_geom(const struct g_class *,
127 static void update_metadata(struct g_virstor_softc *);
128 static void fill_metadata(struct g_virstor_softc *, struct g_virstor_metadata *,
131 static void g_virstor_orphan(struct g_consumer *);
132 static int g_virstor_access(struct g_provider *, int, int, int);
133 static void g_virstor_start(struct bio *);
134 static void g_virstor_dumpconf(struct sbuf *, const char *, struct g_geom *,
135 struct g_consumer *, struct g_provider *);
136 static void g_virstor_done(struct bio *);
138 static void invalid_call(void);
140 * Initialise GEOM class (per-class callback)
143 g_virstor_init(struct g_class *mp __unused)
146 /* Catch map struct size mismatch at compile time; Map entries must
147 * fit into MAXPHYS exactly, with no wasted space. */
148 CTASSERT(VIRSTOR_MAP_BLOCK_ENTRIES*VIRSTOR_MAP_ENTRY_SIZE == MAXPHYS);
150 /* Init UMA zones, TAILQ's, other global vars */
154 * Finalise GEOM class (per-class callback)
157 g_virstor_fini(struct g_class *mp __unused)
160 /* Deinit UMA zones & global vars */
164 * Config (per-class callback)
167 g_virstor_config(struct gctl_req *req, struct g_class *cp, char const *verb)
173 version = gctl_get_paraml(req, "version", sizeof(*version));
174 if (version == NULL) {
175 gctl_error(req, "Failed to get 'version' argument");
178 if (*version != G_VIRSTOR_VERSION) {
179 gctl_error(req, "Userland and kernel versions out of sync");
184 if (strcmp(verb, "add") == 0)
185 virstor_ctl_add(req, cp);
186 else if (strcmp(verb, "stop") == 0 || strcmp(verb, "destroy") == 0)
187 virstor_ctl_stop(req, cp);
188 else if (strcmp(verb, "remove") == 0)
189 virstor_ctl_remove(req, cp);
191 gctl_error(req, "unknown verb: '%s'", verb);
196 * "stop" verb from userland
199 virstor_ctl_stop(struct gctl_req *req, struct g_class *cp)
204 nargs = gctl_get_paraml(req, "nargs", sizeof *nargs);
206 gctl_error(req, "Error fetching argument '%s'", "nargs");
210 gctl_error(req, "Invalid number of arguments");
213 force = gctl_get_paraml(req, "force", sizeof *force);
215 gctl_error(req, "Error fetching argument '%s'", "force");
220 for (i = 0; i < *nargs; i++) {
223 struct g_virstor_softc *sc;
226 sprintf(param, "arg%d", i);
227 name = gctl_get_asciiparam(req, param);
229 gctl_error(req, "No 'arg%d' argument", i);
233 sc = virstor_find_geom(cp, name);
234 LOG_MSG(LVL_INFO, "Stopping %s by the userland command",
237 if ((error = virstor_geom_destroy(sc, TRUE, TRUE)) != 0) {
238 LOG_MSG(LVL_ERROR, "Cannot destroy %s: %d",
239 sc->geom->name, error);
246 * "add" verb from userland - add new component(s) to the structure.
247 * This will be done all at once in here, without going through the
248 * .taste function for new components.
251 virstor_ctl_add(struct gctl_req *req, struct g_class *cp)
253 /* Note: while this is going on, I/O is being done on
254 * the g_up and g_down threads. The idea is to make changes
255 * to softc members in a way that can atomically activate
256 * them all at once. */
257 struct g_virstor_softc *sc;
258 int *hardcode, *nargs;
259 const char *geom_name; /* geom to add a component to */
260 struct g_consumer *fcp;
261 struct g_virstor_bio_q *bq;
266 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
268 gctl_error(req, "Error fetching argument '%s'", "nargs");
272 gctl_error(req, "Invalid number of arguments");
275 hardcode = gctl_get_paraml(req, "hardcode", sizeof(*hardcode));
276 if (hardcode == NULL) {
277 gctl_error(req, "Error fetching argument '%s'", "hardcode");
281 /* Find "our" geom */
282 geom_name = gctl_get_asciiparam(req, "arg0");
283 if (geom_name == NULL) {
284 gctl_error(req, "Error fetching argument '%s'", "geom_name (arg0)");
287 sc = virstor_find_geom(cp, geom_name);
289 gctl_error(req, "Don't know anything about '%s'", geom_name);
293 if (virstor_valid_components(sc) != sc->n_components) {
294 LOG_MSG(LVL_ERROR, "Cannot add components to incomplete "
295 "virstor %s", sc->geom->name);
296 gctl_error(req, "Virstor %s is incomplete", sc->geom->name);
300 fcp = sc->components[0].gcons;
303 for (i = 1; i < *nargs; i++) {
304 struct g_virstor_metadata md;
306 const char *prov_name;
307 struct g_provider *pp;
308 struct g_consumer *cp;
312 snprintf(aname, sizeof aname, "arg%d", i);
313 prov_name = gctl_get_asciiparam(req, aname);
314 if (strncmp(prov_name, _PATH_DEV, strlen(_PATH_DEV)) == 0)
315 prov_name += strlen(_PATH_DEV);
317 pp = g_provider_by_name(prov_name);
319 /* This is the most common error so be verbose about it */
321 gctl_error(req, "Invalid provider: '%s' (added"
322 " %u components)", prov_name, added);
325 gctl_error(req, "Invalid provider: '%s'",
331 cp = g_new_consumer(sc->geom);
333 gctl_error(req, "Cannot create consumer");
337 error = g_attach(cp, pp);
339 gctl_error(req, "Cannot attach a consumer to %s",
341 g_destroy_consumer(cp);
345 if (fcp->acr != 0 || fcp->acw != 0 || fcp->ace != 0) {
346 error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
348 gctl_error(req, "Access request failed for %s",
350 g_destroy_consumer(cp);
355 if (fcp->provider->sectorsize != pp->sectorsize) {
356 gctl_error(req, "Sector size doesn't fit for %s",
358 g_destroy_consumer(cp);
362 for (j = 0; j < sc->n_components; j++) {
363 if (strcmp(sc->components[j].gcons->provider->name,
365 gctl_error(req, "Component %s already in %s",
366 pp->name, sc->geom->name);
367 g_destroy_consumer(cp);
372 sc->components = realloc(sc->components,
373 sizeof(*sc->components) * (sc->n_components + 1),
374 M_GVIRSTOR, M_WAITOK);
376 nc = sc->n_components;
377 sc->components[nc].gcons = cp;
378 sc->components[nc].sc = sc;
379 sc->components[nc].index = nc;
380 sc->components[nc].chunk_count = cp->provider->mediasize /
382 sc->components[nc].chunk_next = 0;
383 sc->components[nc].chunk_reserved = 0;
385 if (sc->components[nc].chunk_count < 4) {
386 gctl_error(req, "Provider too small: %s",
388 g_destroy_consumer(cp);
392 fill_metadata(sc, &md, nc, *hardcode);
393 write_metadata(cp, &md);
394 /* The new component becomes visible when n_components is
400 /* This call to update_metadata() is critical. In case there's a
401 * power failure in the middle of it and some components are updated
402 * while others are not, there will be trouble on next .taste() iff
403 * a non-updated component is detected first */
406 LOG_MSG(LVL_INFO, "Added %d component(s) to %s", added,
408 /* Fire off BIOs previously queued because there wasn't any
409 * physical space left. If the BIOs still can't be satisfied
410 * they will again be added to the end of the queue (during
411 * which the mutex will be recursed) */
412 bq = malloc(sizeof(*bq), M_GVIRSTOR, M_WAITOK);
414 mtx_lock(&sc->delayed_bio_q_mtx);
415 /* First, insert a sentinel to the queue end, so we don't
416 * end up in an infinite loop if there's still no free
417 * space available. */
418 STAILQ_INSERT_TAIL(&sc->delayed_bio_q, bq, linkage);
419 while (!STAILQ_EMPTY(&sc->delayed_bio_q)) {
420 bq = STAILQ_FIRST(&sc->delayed_bio_q);
421 if (bq->bio != NULL) {
422 g_virstor_start(bq->bio);
423 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage);
424 free(bq, M_GVIRSTOR);
426 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage);
427 free(bq, M_GVIRSTOR);
431 mtx_unlock(&sc->delayed_bio_q_mtx);
436 * Find a geom handled by the class
438 static struct g_virstor_softc *
439 virstor_find_geom(const struct g_class *cp, const char *name)
443 LIST_FOREACH(gp, &cp->geom, geom) {
444 if (strcmp(name, gp->name) == 0)
451 * Update metadata on all components to reflect the current state
456 * Expects things to be set up so write_metadata() can work, i.e.
457 * the topology lock must be held.
460 update_metadata(struct g_virstor_softc *sc)
462 struct g_virstor_metadata md;
465 if (virstor_valid_components(sc) != sc->n_components)
466 return; /* Incomplete device */
467 LOG_MSG(LVL_DEBUG, "Updating metadata on components for %s",
469 /* Update metadata on components */
470 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__,
471 sc->geom->class->name, sc->geom->name);
473 for (n = 0; n < sc->n_components; n++) {
474 read_metadata(sc->components[n].gcons, &md);
475 md.chunk_next = sc->components[n].chunk_next;
476 md.flags = sc->components[n].flags;
477 md.md_count = sc->n_components;
478 write_metadata(sc->components[n].gcons, &md);
483 * Fills metadata (struct md) from information stored in softc and the nc'th
484 * component of virstor
487 fill_metadata(struct g_virstor_softc *sc, struct g_virstor_metadata *md,
488 u_int nc, u_int hardcode)
490 struct g_virstor_component *c;
492 bzero(md, sizeof *md);
493 c = &sc->components[nc];
495 strncpy(md->md_magic, G_VIRSTOR_MAGIC, sizeof md->md_magic);
496 md->md_version = G_VIRSTOR_VERSION;
497 strncpy(md->md_name, sc->geom->name, sizeof md->md_name);
499 md->md_virsize = sc->virsize;
500 md->md_chunk_size = sc->chunk_size;
501 md->md_count = sc->n_components;
504 strncpy(md->provider, c->gcons->provider->name,
505 sizeof md->provider);
508 md->provsize = c->gcons->provider->mediasize;
509 md->chunk_count = c->chunk_count;
510 md->chunk_next = c->chunk_next;
511 md->chunk_reserved = c->chunk_reserved;
512 md->flags = c->flags;
516 * Remove a component from virstor device.
517 * Can only be done if the component is unallocated.
520 virstor_ctl_remove(struct gctl_req *req, struct g_class *cp)
522 /* As this is executed in parallel to I/O, operations on virstor
523 * structures must be as atomic as possible. */
524 struct g_virstor_softc *sc;
526 const char *geom_name;
530 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
532 gctl_error(req, "Error fetching argument '%s'", "nargs");
536 gctl_error(req, "Invalid number of arguments");
539 /* Find "our" geom */
540 geom_name = gctl_get_asciiparam(req, "arg0");
541 if (geom_name == NULL) {
542 gctl_error(req, "Error fetching argument '%s'",
546 sc = virstor_find_geom(cp, geom_name);
548 gctl_error(req, "Don't know anything about '%s'", geom_name);
552 if (virstor_valid_components(sc) != sc->n_components) {
553 LOG_MSG(LVL_ERROR, "Cannot remove components from incomplete "
554 "virstor %s", sc->geom->name);
555 gctl_error(req, "Virstor %s is incomplete", sc->geom->name);
560 for (i = 1; i < *nargs; i++) {
562 const char *prov_name;
564 struct g_virstor_component *newcomp, *compbak;
566 sprintf(param, "arg%d", i);
567 prov_name = gctl_get_asciiparam(req, param);
568 if (strncmp(prov_name, _PATH_DEV, strlen(_PATH_DEV)) == 0)
569 prov_name += strlen(_PATH_DEV);
572 for (j = 0; j < sc->n_components; j++) {
573 if (strcmp(sc->components[j].gcons->provider->name,
580 LOG_MSG(LVL_ERROR, "No %s component in %s",
581 prov_name, sc->geom->name);
585 compbak = sc->components;
586 newcomp = malloc(sc->n_components * sizeof(*sc->components),
587 M_GVIRSTOR, M_WAITOK | M_ZERO);
588 bcopy(sc->components, newcomp, found * sizeof(*sc->components));
589 bcopy(&sc->components[found + 1], newcomp + found,
590 found * sizeof(*sc->components));
591 if ((sc->components[j].flags & VIRSTOR_PROVIDER_ALLOCATED) != 0) {
592 LOG_MSG(LVL_ERROR, "Allocated provider %s cannot be "
594 prov_name, sc->geom->name);
595 free(newcomp, M_GVIRSTOR);
596 /* We'll consider this non-fatal error */
599 /* Renumerate unallocated components */
600 for (j = 0; j < sc->n_components-1; j++) {
601 if ((sc->components[j].flags &
602 VIRSTOR_PROVIDER_ALLOCATED) == 0) {
603 sc->components[j].index = j;
606 /* This is the critical section. If a component allocation
607 * event happens while both variables are not yet set,
608 * there will be trouble. Something will panic on encountering
609 * NULL sc->components[x].gcomp member.
610 * Luckily, component allocation happens very rarely and
611 * removing components is an abnormal action in any case. */
612 sc->components = newcomp;
614 /* End critical section */
617 if (clear_metadata(&compbak[found]) != 0) {
618 LOG_MSG(LVL_WARNING, "Trouble ahead: cannot clear "
619 "metadata on %s", prov_name);
621 g_detach(compbak[found].gcons);
622 g_destroy_consumer(compbak[found].gcons);
625 free(compbak, M_GVIRSTOR);
630 /* This call to update_metadata() is critical. In case there's a
631 * power failure in the middle of it and some components are updated
632 * while others are not, there will be trouble on next .taste() iff
633 * a non-updated component is detected first */
637 LOG_MSG(LVL_INFO, "Removed %d component(s) from %s", removed,
642 * Clear metadata sector on component
645 clear_metadata(struct g_virstor_component *comp)
650 LOG_MSG(LVL_INFO, "Clearing metadata on %s",
651 comp->gcons->provider->name);
653 error = g_access(comp->gcons, 0, 1, 0);
656 buf = malloc(comp->gcons->provider->sectorsize, M_GVIRSTOR,
658 error = g_write_data(comp->gcons,
659 comp->gcons->provider->mediasize -
660 comp->gcons->provider->sectorsize,
662 comp->gcons->provider->sectorsize);
663 free(buf, M_GVIRSTOR);
664 g_access(comp->gcons, 0, -1, 0);
669 * Destroy geom forcibly.
672 g_virstor_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
675 struct g_virstor_softc *sc;
679 KASSERT(sc != NULL, ("%s: NULL sc", __func__));
682 LOG_MSG(LVL_DEBUG, "%s called for %s, sc=%p", __func__, gp->name,
693 LOG_MSG(LVL_INFO, "INVARIANTS detected");
694 LOG_MSG(LVL_INFO, "Verifying allocation "
695 "table for %s", sc->geom->name);
697 for (n = 0; n < sc->chunk_count; n++) {
698 if (sc->map[n].flags || VIRSTOR_MAP_ALLOCATED != 0)
701 LOG_MSG(LVL_INFO, "Device %s has %d allocated chunks",
702 sc->geom->name, count);
705 if (virstor_valid_components(sc) != sc->n_components) {
706 /* This is a incomplete virstor device (not all
707 * components have been found) */
708 LOG_MSG(LVL_ERROR, "Device %s is incomplete",
712 error = g_access(sc->components[0].gcons, 1, 0, 0);
713 KASSERT(error == 0, ("%s: g_access failed (%d)", __func__,
715 /* Compare the whole on-disk allocation table with what's
716 * currently in memory */
717 while (n < sc->chunk_count) {
718 buf = g_read_data(sc->components[0].gcons, off,
719 sc->sectorsize, &error);
720 KASSERT(buf != NULL, ("g_read_data returned NULL (%d) "
721 "for read at %jd", error, off));
722 if (bcmp(buf, &sc->map[n], sc->sectorsize) != 0) {
723 LOG_MSG(LVL_ERROR, "ERROR in allocation table, "
724 "entry %d, offset %jd", n, off);
728 n += sc->me_per_sector;
729 off += sc->sectorsize;
732 error = g_access(sc->components[0].gcons, -1, 0, 0);
733 KASSERT(error == 0, ("%s: g_access failed (%d) on exit",
736 LOG_MSG(LVL_ERROR, "ALLOCATION TABLE CORRUPTED FOR %s "
737 "(%d sectors don't match, max %zu allocations)",
738 sc->geom->name, count,
739 count * sc->me_per_sector);
741 LOG_MSG(LVL_INFO, "Allocation table ok for %s",
747 virstor_geom_destroy(sc, FALSE, FALSE);
755 * Taste event (per-class callback)
756 * Examines a provider and creates geom instances if needed
758 static struct g_geom *
759 g_virstor_taste(struct g_class *mp, struct g_provider *pp, int flags)
761 struct g_virstor_metadata md;
763 struct g_consumer *cp;
764 struct g_virstor_softc *sc;
767 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
769 LOG_MSG(LVL_DEBUG, "Tasting %s", pp->name);
771 /* We need a dummy geom to attach a consumer to the given provider */
772 gp = g_new_geomf(mp, "virstor:taste.helper");
773 gp->start = (void *)invalid_call; /* XXX: hacked up so the */
774 gp->access = (void *)invalid_call; /* compiler doesn't complain. */
775 gp->orphan = (void *)invalid_call; /* I really want these to fail. */
777 cp = g_new_consumer(gp);
779 error = read_metadata(cp, &md);
781 g_destroy_consumer(cp);
787 if (strcmp(md.md_magic, G_VIRSTOR_MAGIC) != 0)
789 if (md.md_version != G_VIRSTOR_VERSION) {
790 LOG_MSG(LVL_ERROR, "Kernel module version invalid "
791 "to handle %s (%s) : %d should be %d",
792 md.md_name, pp->name, md.md_version, G_VIRSTOR_VERSION);
795 if (md.provsize != pp->mediasize)
798 /* If the provider name is hardcoded, use the offered provider only
799 * if it's been offered with its proper name (the one used in
800 * the label command). */
801 if (md.provider[0] != '\0') {
802 if (strcmp(md.provider, pp->name) != 0)
806 /* Iterate all geoms this class already knows about to see if a new
807 * geom instance of this class needs to be created (in case the provider
808 * is first from a (possibly) multi-consumer geom) or it just needs
809 * to be added to an existing instance. */
812 LIST_FOREACH(gp, &mp->geom, geom) {
816 if (strcmp(md.md_name, sc->geom->name) != 0)
818 if (md.md_id != sc->id)
822 if (gp != NULL) { /* We found an existing geom instance; add to it */
823 LOG_MSG(LVL_INFO, "Adding %s to %s", pp->name, md.md_name);
824 error = add_provider_to_geom(sc, pp, &md);
826 LOG_MSG(LVL_ERROR, "Error adding %s to %s (error %d)",
827 pp->name, md.md_name, error);
830 } else { /* New geom instance needs to be created */
831 gp = create_virstor_geom(mp, &md);
833 LOG_MSG(LVL_ERROR, "Error creating new instance of "
834 "class %s: %s", mp->name, md.md_name);
835 LOG_MSG(LVL_DEBUG, "Error creating %s at %s",
836 md.md_name, pp->name);
840 LOG_MSG(LVL_INFO, "Adding %s to %s (first found)", pp->name,
842 error = add_provider_to_geom(sc, pp, &md);
844 LOG_MSG(LVL_ERROR, "Error adding %s to %s (error %d)",
845 pp->name, md.md_name, error);
846 virstor_geom_destroy(sc, TRUE, FALSE);
855 * Destroyes consumer passed to it in arguments. Used as a callback
859 delay_destroy_consumer(void *arg, int flags __unused)
861 struct g_consumer *c = arg;
862 KASSERT(c != NULL, ("%s: invalid consumer", __func__));
863 LOG_MSG(LVL_DEBUG, "Consumer %s destroyed with delay",
866 g_destroy_consumer(c);
870 * Remove a component (consumer) from geom instance; If it's the first
871 * component being removed, orphan the provider to announce geom's being
875 remove_component(struct g_virstor_softc *sc, struct g_virstor_component *comp,
878 struct g_consumer *c;
880 KASSERT(comp->gcons != NULL, ("Component with no consumer in %s",
885 KASSERT(c->provider != NULL, ("%s: no provider", __func__));
886 LOG_MSG(LVL_DEBUG, "Component %s removed from %s", c->provider->name,
888 if (sc->provider != NULL) {
890 sc->provider->flags |= G_PF_WITHER;
891 g_orphan_provider(sc->provider, ENXIO);
893 LOG_MSG(LVL_INFO, "Removing provider %s", sc->geom->name);
896 if (c->acr > 0 || c->acw > 0 || c->ace > 0)
897 g_access(c, -c->acr, -c->acw, -c->ace);
899 /* Destroy consumer after it's tasted */
900 g_post_event(delay_destroy_consumer, c, M_WAITOK, NULL);
903 g_destroy_consumer(c);
908 * Destroy geom - called internally
909 * See g_virstor_destroy_geom for the other one
912 virstor_geom_destroy(struct g_virstor_softc *sc, boolean_t force,
915 struct g_provider *pp;
925 if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
926 LOG_MSG(force ? LVL_WARNING : LVL_ERROR,
927 "Device %s is still open.", pp->name);
932 for (n = 0; n < sc->n_components; n++) {
933 if (sc->components[n].gcons != NULL)
934 remove_component(sc, &sc->components[n], delay);
940 KASSERT(sc->provider == NULL, ("Provider still exists for %s",
943 /* XXX: This might or might not work, since we're called with
944 * the topology lock held. Also, it might panic the kernel if
945 * the error'd BIO is in softupdates code. */
946 mtx_lock(&sc->delayed_bio_q_mtx);
947 while (!STAILQ_EMPTY(&sc->delayed_bio_q)) {
948 struct g_virstor_bio_q *bq;
949 bq = STAILQ_FIRST(&sc->delayed_bio_q);
950 bq->bio->bio_error = ENOSPC;
951 g_io_deliver(bq->bio, EIO);
952 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage);
953 free(bq, M_GVIRSTOR);
955 mtx_unlock(&sc->delayed_bio_q_mtx);
956 mtx_destroy(&sc->delayed_bio_q_mtx);
958 free(sc->map, M_GVIRSTOR);
959 free(sc->components, M_GVIRSTOR);
960 bzero(sc, sizeof *sc);
961 free(sc, M_GVIRSTOR);
963 pp = LIST_FIRST(&gp->provider); /* We only offer one provider */
964 if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
965 LOG_MSG(LVL_DEBUG, "Device %s destroyed", gp->name);
967 g_wither_geom(gp, ENXIO);
973 * Utility function: read metadata & decode. Wants topology lock to be
977 read_metadata(struct g_consumer *cp, struct g_virstor_metadata *md)
979 struct g_provider *pp;
984 error = g_access(cp, 1, 0, 0);
989 buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
992 g_access(cp, -1, 0, 0);
996 virstor_metadata_decode(buf, md);
1003 * Utility function: encode & write metadata. Assumes topology lock is
1007 write_metadata(struct g_consumer *cp, struct g_virstor_metadata *md)
1009 struct g_provider *pp;
1013 KASSERT(cp != NULL && md != NULL && cp->provider != NULL,
1014 ("Something's fishy in %s", __func__));
1015 LOG_MSG(LVL_DEBUG, "Writing metadata on %s", cp->provider->name);
1016 g_topology_assert();
1017 error = g_access(cp, 0, 1, 0);
1022 buf = malloc(pp->sectorsize, M_GVIRSTOR, M_WAITOK);
1023 virstor_metadata_encode(md, buf);
1024 g_topology_unlock();
1025 error = g_write_data(cp, pp->mediasize - pp->sectorsize, buf,
1028 g_access(cp, 0, -1, 0);
1030 free(buf, M_GVIRSTOR);
1035 * Creates a new instance of this GEOM class, initialise softc
1037 static struct g_geom *
1038 create_virstor_geom(struct g_class *mp, struct g_virstor_metadata *md)
1041 struct g_virstor_softc *sc;
1043 LOG_MSG(LVL_DEBUG, "Creating geom instance for %s (id=%u)",
1044 md->md_name, md->md_id);
1046 if (md->md_count < 1 || md->md_chunk_size < 1 ||
1047 md->md_virsize < md->md_chunk_size) {
1048 /* This is bogus configuration, and probably means data is
1049 * somehow corrupted. Panic, maybe? */
1050 LOG_MSG(LVL_ERROR, "Nonsensical metadata information for %s",
1055 /* Check if it's already created */
1056 LIST_FOREACH(gp, &mp->geom, geom) {
1058 if (sc != NULL && strcmp(sc->geom->name, md->md_name) == 0) {
1059 LOG_MSG(LVL_WARNING, "Geom %s already exists",
1061 if (sc->id != md->md_id) {
1063 "Some stale or invalid components "
1064 "exist for virstor device named %s. "
1065 "You will need to <CLEAR> all stale "
1066 "components and maybe reconfigure "
1067 "the virstor device. Tune "
1068 "kern.geom.virstor.debug sysctl up "
1069 "for more information.",
1075 gp = g_new_geomf(mp, "%s", md->md_name);
1076 gp->softc = NULL; /* to circumevent races that test softc */
1078 gp->start = g_virstor_start;
1079 gp->spoiled = g_virstor_orphan;
1080 gp->orphan = g_virstor_orphan;
1081 gp->access = g_virstor_access;
1082 gp->dumpconf = g_virstor_dumpconf;
1084 sc = malloc(sizeof(*sc), M_GVIRSTOR, M_WAITOK | M_ZERO);
1086 sc->n_components = md->md_count;
1087 sc->components = malloc(sizeof(struct g_virstor_component) * md->md_count,
1088 M_GVIRSTOR, M_WAITOK | M_ZERO);
1089 sc->chunk_size = md->md_chunk_size;
1090 sc->virsize = md->md_virsize;
1091 STAILQ_INIT(&sc->delayed_bio_q);
1092 mtx_init(&sc->delayed_bio_q_mtx, "gvirstor_delayed_bio_q_mtx",
1093 "gvirstor", MTX_DEF | MTX_RECURSE);
1096 sc->provider = NULL; /* virstor_check_and_run will create it */
1099 LOG_MSG(LVL_ANNOUNCE, "Device %s created", sc->geom->name);
1105 * Add provider to a GEOM class instance
1108 add_provider_to_geom(struct g_virstor_softc *sc, struct g_provider *pp,
1109 struct g_virstor_metadata *md)
1111 struct g_virstor_component *component;
1112 struct g_consumer *cp, *fcp;
1116 if (md->no >= sc->n_components)
1119 /* "Current" compontent */
1120 component = &(sc->components[md->no]);
1121 if (component->gcons != NULL)
1125 fcp = LIST_FIRST(&gp->consumer);
1127 cp = g_new_consumer(gp);
1128 error = g_attach(cp, pp);
1131 g_destroy_consumer(cp);
1136 if (fcp->provider->sectorsize != pp->sectorsize) {
1137 /* TODO: this can be made to work */
1138 LOG_MSG(LVL_ERROR, "Provider %s of %s has invalid "
1139 "sector size (%d)", pp->name, sc->geom->name,
1143 if (fcp->acr > 0 || fcp->acw || fcp->ace > 0) {
1144 /* Replicate access permissions from first "live" consumer
1146 error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
1149 g_destroy_consumer(cp);
1155 /* Bring up a new component */
1156 cp->private = component;
1157 component->gcons = cp;
1159 component->index = md->no;
1160 component->chunk_count = md->chunk_count;
1161 component->chunk_next = md->chunk_next;
1162 component->chunk_reserved = md->chunk_reserved;
1163 component->flags = md->flags;
1165 LOG_MSG(LVL_DEBUG, "%s attached to %s", pp->name, sc->geom->name);
1167 virstor_check_and_run(sc);
1172 * Check if everything's ready to create the geom provider & device entry,
1173 * create and start provider.
1174 * Called ultimately by .taste, from g_event thread
1177 virstor_check_and_run(struct g_virstor_softc *sc)
1184 if (virstor_valid_components(sc) != sc->n_components)
1187 if (virstor_valid_components(sc) == 0) {
1188 /* This is actually a candidate for panic() */
1189 LOG_MSG(LVL_ERROR, "No valid components for %s?",
1190 sc->provider->name);
1194 sc->sectorsize = sc->components[0].gcons->provider->sectorsize;
1196 /* Initialise allocation map from the first consumer */
1197 sc->chunk_count = sc->virsize / sc->chunk_size;
1198 if (sc->chunk_count * (off_t)sc->chunk_size != sc->virsize) {
1199 LOG_MSG(LVL_WARNING, "Device %s truncated to %ju bytes",
1201 sc->chunk_count * (off_t)sc->chunk_size);
1203 sc->map_size = sc->chunk_count * sizeof *(sc->map);
1204 /* The following allocation is in order of 4MB - 8MB */
1205 sc->map = malloc(sc->map_size, M_GVIRSTOR, M_WAITOK);
1206 KASSERT(sc->map != NULL, ("%s: Memory allocation error (%zu bytes) for %s",
1207 __func__, sc->map_size, sc->provider->name));
1208 sc->map_sectors = sc->map_size / sc->sectorsize;
1211 for (n = 0; n < sc->n_components; n++)
1212 count += sc->components[n].chunk_count;
1213 LOG_MSG(LVL_INFO, "Device %s has %zu physical chunks and %zu virtual "
1215 sc->geom->name, count, sc->chunk_count, sc->chunk_size / 1024);
1217 error = g_access(sc->components[0].gcons, 1, 0, 0);
1219 LOG_MSG(LVL_ERROR, "Cannot acquire read access for %s to "
1220 "read allocation map for %s",
1221 sc->components[0].gcons->provider->name,
1225 /* Read in the allocation map */
1226 LOG_MSG(LVL_DEBUG, "Reading map for %s from %s", sc->geom->name,
1227 sc->components[0].gcons->provider->name);
1228 off = count = n = 0;
1229 while (count < sc->map_size) {
1230 struct g_virstor_map_entry *mapbuf;
1233 bs = MIN(MAXPHYS, sc->map_size - count);
1234 if (bs % sc->sectorsize != 0) {
1235 /* Check for alignment errors */
1236 bs = (bs / sc->sectorsize) * sc->sectorsize;
1239 LOG_MSG(LVL_ERROR, "Trouble: map is not sector-aligned "
1240 "for %s on %s", sc->geom->name,
1241 sc->components[0].gcons->provider->name);
1243 mapbuf = g_read_data(sc->components[0].gcons, off, bs, &error);
1244 if (mapbuf == NULL) {
1245 free(sc->map, M_GVIRSTOR);
1246 LOG_MSG(LVL_ERROR, "Error reading allocation map "
1247 "for %s from %s (offset %ju) (error %d)",
1249 sc->components[0].gcons->provider->name,
1254 bcopy(mapbuf, &sc->map[n], bs);
1257 n += bs / sizeof *(sc->map);
1260 g_access(sc->components[0].gcons, -1, 0, 0);
1261 LOG_MSG(LVL_DEBUG, "Read map for %s", sc->geom->name);
1263 /* find first component with allocatable chunks */
1265 for (n = 0; n < sc->n_components; n++) {
1266 if (sc->components[n].chunk_next <
1267 sc->components[n].chunk_count) {
1273 /* not found? set it to the last component and handle it
1275 index = sc->n_components - 1;
1277 if (index >= sc->n_components - g_virstor_component_watermark - 1) {
1278 LOG_MSG(LVL_WARNING, "Device %s running out of components "
1279 "(%d/%u: %s)", sc->geom->name,
1282 sc->components[index].gcons->provider->name);
1284 sc->curr_component = index;
1286 if (sc->components[index].chunk_next >=
1287 sc->components[index].chunk_count - g_virstor_chunk_watermark) {
1288 LOG_MSG(LVL_WARNING,
1289 "Component %s of %s is running out of free space "
1291 sc->components[index].gcons->provider->name,
1292 sc->geom->name, sc->components[index].chunk_count -
1293 sc->components[index].chunk_next);
1296 sc->me_per_sector = sc->sectorsize / sizeof *(sc->map);
1297 if (sc->sectorsize % sizeof *(sc->map) != 0) {
1299 "%s: Map entries don't fit exactly in a sector (%s)",
1300 __func__, sc->geom->name);
1304 /* Recalculate allocated chunks in components & at the same time
1305 * verify map data is sane. We could trust metadata on this, but
1306 * we want to make sure. */
1307 for (n = 0; n < sc->n_components; n++)
1308 sc->components[n].chunk_next = sc->components[n].chunk_reserved;
1310 for (n = 0; n < sc->chunk_count; n++) {
1311 if (sc->map[n].provider_no >= sc->n_components ||
1312 sc->map[n].provider_chunk >=
1313 sc->components[sc->map[n].provider_no].chunk_count) {
1314 LOG_MSG(LVL_ERROR, "%s: Invalid entry %u in map for %s",
1315 __func__, (u_int)n, sc->geom->name);
1316 LOG_MSG(LVL_ERROR, "%s: provider_no: %u, n_components: %u"
1317 " provider_chunk: %u, chunk_count: %u", __func__,
1318 sc->map[n].provider_no, sc->n_components,
1319 sc->map[n].provider_chunk,
1320 sc->components[sc->map[n].provider_no].chunk_count);
1323 if (sc->map[n].flags & VIRSTOR_MAP_ALLOCATED)
1324 sc->components[sc->map[n].provider_no].chunk_next++;
1327 sc->provider = g_new_providerf(sc->geom, "virstor/%s",
1330 sc->provider->sectorsize = sc->sectorsize;
1331 sc->provider->mediasize = sc->virsize;
1332 g_error_provider(sc->provider, 0);
1334 LOG_MSG(LVL_INFO, "%s activated", sc->provider->name);
1335 LOG_MSG(LVL_DEBUG, "%s starting with current component %u, starting "
1336 "chunk %u", sc->provider->name, sc->curr_component,
1337 sc->components[sc->curr_component].chunk_next);
1341 * Returns count of active providers in this geom instance
1344 virstor_valid_components(struct g_virstor_softc *sc)
1349 KASSERT(sc != NULL, ("%s: softc is NULL", __func__));
1350 KASSERT(sc->components != NULL, ("%s: sc->components is NULL", __func__));
1351 for (i = 0; i < sc->n_components; i++)
1352 if (sc->components[i].gcons != NULL)
1358 * Called when the consumer gets orphaned (?)
1361 g_virstor_orphan(struct g_consumer *cp)
1363 struct g_virstor_softc *sc;
1364 struct g_virstor_component *comp;
1367 g_topology_assert();
1374 KASSERT(comp != NULL, ("%s: No component in private part of consumer",
1376 remove_component(sc, comp, FALSE);
1377 if (virstor_valid_components(sc) == 0)
1378 virstor_geom_destroy(sc, TRUE, FALSE);
1382 * Called to notify geom when it's been opened, and for what intent
1385 g_virstor_access(struct g_provider *pp, int dr, int dw, int de)
1387 struct g_consumer *c;
1388 struct g_virstor_softc *sc;
1392 KASSERT(pp != NULL, ("%s: NULL provider", __func__));
1394 KASSERT(gp != NULL, ("%s: NULL geom", __func__));
1398 /* It seems that .access can be called with negative dr,dw,dx
1399 * in this case but I want to check for myself */
1400 LOG_MSG(LVL_WARNING, "access(%d, %d, %d) for %s",
1401 dr, dw, de, pp->name);
1402 /* This should only happen when geom is withered so
1403 * allow only negative requests */
1404 KASSERT(dr <= 0 && dw <= 0 && de <= 0,
1405 ("%s: Positive access for %s", __func__, pp->name));
1406 if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0)
1407 LOG_MSG(LVL_DEBUG, "Device %s definitely destroyed",
1412 /* Grab an exclusive bit to propagate on our consumers on first open */
1413 if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)
1415 /* ... drop it on close */
1416 if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0) {
1418 update_metadata(sc); /* Writes statistical information */
1422 LIST_FOREACH(c, &gp->consumer, consumer) {
1423 KASSERT(c != NULL, ("%s: consumer is NULL", __func__));
1424 error = g_access(c, dr, dw, de);
1426 struct g_consumer *c2;
1428 /* Backout earlier changes */
1429 LIST_FOREACH(c2, &gp->consumer, consumer) {
1430 if (c2 == c) /* all eariler components fixed */
1432 g_access(c2, -dr, -dw, -de);
1441 * Generate XML dump of current state
1444 g_virstor_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1445 struct g_consumer *cp, struct g_provider *pp)
1447 struct g_virstor_softc *sc;
1449 g_topology_assert();
1452 if (sc == NULL || pp != NULL)
1456 /* For each component */
1457 struct g_virstor_component *comp;
1462 sbuf_printf(sb, "%s<ComponentIndex>%u</ComponentIndex>\n",
1463 indent, comp->index);
1464 sbuf_printf(sb, "%s<ChunkCount>%u</ChunkCount>\n",
1465 indent, comp->chunk_count);
1466 sbuf_printf(sb, "%s<ChunksUsed>%u</ChunksUsed>\n",
1467 indent, comp->chunk_next);
1468 sbuf_printf(sb, "%s<ChunksReserved>%u</ChunksReserved>\n",
1469 indent, comp->chunk_reserved);
1470 sbuf_printf(sb, "%s<StorageFree>%u%%</StorageFree>\n",
1472 comp->chunk_next > 0 ? 100 -
1473 ((comp->chunk_next + comp->chunk_reserved) * 100) /
1474 comp->chunk_count : 100);
1476 /* For the whole thing */
1477 u_int count, used, i;
1480 count = used = size = 0;
1481 for (i = 0; i < sc->n_components; i++) {
1482 if (sc->components[i].gcons != NULL) {
1483 count += sc->components[i].chunk_count;
1484 used += sc->components[i].chunk_next +
1485 sc->components[i].chunk_reserved;
1486 size += sc->components[i].gcons->
1487 provider->mediasize;
1491 sbuf_printf(sb, "%s<Status>"
1492 "Components=%u, Online=%u</Status>\n", indent,
1493 sc->n_components, virstor_valid_components(sc));
1494 sbuf_printf(sb, "%s<State>%u%% physical free</State>\n",
1495 indent, 100-(used * 100) / count);
1496 sbuf_printf(sb, "%s<ChunkSize>%zu</ChunkSize>\n", indent,
1498 sbuf_printf(sb, "%s<PhysicalFree>%u%%</PhysicalFree>\n",
1499 indent, used > 0 ? 100 - (used * 100) / count : 100);
1500 sbuf_printf(sb, "%s<ChunkPhysicalCount>%u</ChunkPhysicalCount>\n",
1502 sbuf_printf(sb, "%s<ChunkVirtualCount>%zu</ChunkVirtualCount>\n",
1503 indent, sc->chunk_count);
1504 sbuf_printf(sb, "%s<PhysicalBacking>%zu%%</PhysicalBacking>\n",
1506 (count * 100) / sc->chunk_count);
1507 sbuf_printf(sb, "%s<PhysicalBackingSize>%jd</PhysicalBackingSize>\n",
1509 sbuf_printf(sb, "%s<VirtualSize>%jd</VirtualSize>\n", indent,
1515 * GEOM .done handler
1516 * Can't use standard handler because one requested IO may
1517 * fork into additional data IOs
1520 g_virstor_done(struct bio *b)
1522 struct g_virstor_softc *sc;
1523 struct bio *parent_b;
1525 parent_b = b->bio_parent;
1526 sc = parent_b->bio_to->geom->softc;
1528 if (b->bio_error != 0) {
1529 LOG_MSG(LVL_ERROR, "Error %d for offset=%ju, length=%ju, %s",
1530 b->bio_error, b->bio_offset, b->bio_length,
1532 if (parent_b->bio_error == 0)
1533 parent_b->bio_error = b->bio_error;
1536 parent_b->bio_inbed++;
1537 parent_b->bio_completed += b->bio_completed;
1539 if (parent_b->bio_children == parent_b->bio_inbed) {
1540 parent_b->bio_completed = parent_b->bio_length;
1541 g_io_deliver(parent_b, parent_b->bio_error);
1548 * Called in g_down thread
1551 g_virstor_start(struct bio *b)
1553 struct g_virstor_softc *sc;
1554 struct g_virstor_component *comp;
1556 struct g_provider *pp;
1558 off_t offset, length;
1559 struct bio_queue_head bq;
1560 size_t chunk_size; /* cached for convenience */
1564 sc = pp->geom->softc;
1565 KASSERT(sc != NULL, ("%s: no softc (error=%d, device=%s)", __func__,
1566 b->bio_to->error, b->bio_to->name));
1568 LOG_REQ(LVL_MOREDEBUG, b, "%s", __func__);
1570 switch (b->bio_cmd) {
1576 g_io_deliver(b, EOPNOTSUPP);
1580 LOG_MSG(LVL_DEBUG2, "BIO arrived, size=%ju", b->bio_length);
1583 chunk_size = sc->chunk_size;
1585 offset = b->bio_offset; /* virtual offset and length */
1586 length = b->bio_length;
1588 while (length > 0) {
1589 size_t chunk_index, in_chunk_offset, in_chunk_length;
1590 struct virstor_map_entry *me;
1592 chunk_index = offset / chunk_size; /* round downwards */
1593 in_chunk_offset = offset % chunk_size;
1594 in_chunk_length = min(length, chunk_size - in_chunk_offset);
1595 LOG_MSG(LVL_DEBUG, "Mapped %s(%ju, %ju) to (%zu,%zu,%zu)",
1596 b->bio_cmd == BIO_READ ? "R" : "W",
1598 chunk_index, in_chunk_offset, in_chunk_length);
1599 me = &sc->map[chunk_index];
1601 if (b->bio_cmd == BIO_READ || b->bio_cmd == BIO_DELETE) {
1602 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) {
1603 /* Reads from unallocated chunks return zeroed
1605 if (b->bio_cmd == BIO_READ)
1606 bzero(addr, in_chunk_length);
1608 comp = &sc->components[me->provider_no];
1610 cb = g_clone_bio(b);
1612 bioq_dismantle(&bq);
1613 if (b->bio_error == 0)
1614 b->bio_error = ENOMEM;
1615 g_io_deliver(b, b->bio_error);
1618 cb->bio_to = comp->gcons->provider;
1619 cb->bio_done = g_virstor_done;
1621 (off_t)me->provider_chunk * (off_t)chunk_size
1623 cb->bio_length = in_chunk_length;
1624 cb->bio_data = addr;
1625 cb->bio_caller1 = comp;
1626 bioq_disksort(&bq, cb);
1628 } else { /* handle BIO_WRITE */
1629 KASSERT(b->bio_cmd == BIO_WRITE,
1630 ("%s: Unknown command %d", __func__,
1633 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) {
1634 /* We have a virtual chunk, represented by
1635 * the "me" entry, but it's not yet allocated
1636 * (tied to) a physical chunk. So do it now. */
1637 struct virstor_map_entry *data_me;
1638 u_int phys_chunk, comp_no;
1642 error = allocate_chunk(sc, &comp, &comp_no,
1645 /* We cannot allocate a physical chunk
1646 * to satisfy this request, so we'll
1647 * delay it to when we can...
1648 * XXX: this will prevent the fs from
1649 * being umounted! */
1650 struct g_virstor_bio_q *biq;
1651 biq = malloc(sizeof *biq, M_GVIRSTOR,
1654 bioq_dismantle(&bq);
1655 if (b->bio_error == 0)
1656 b->bio_error = ENOMEM;
1657 g_io_deliver(b, b->bio_error);
1661 mtx_lock(&sc->delayed_bio_q_mtx);
1662 STAILQ_INSERT_TAIL(&sc->delayed_bio_q,
1664 mtx_unlock(&sc->delayed_bio_q_mtx);
1665 LOG_MSG(LVL_WARNING, "Delaying BIO "
1666 "(size=%ju) until free physical "
1667 "space can be found on %s",
1669 sc->provider->name);
1672 LOG_MSG(LVL_DEBUG, "Allocated chunk %u on %s "
1675 comp->gcons->provider->name,
1676 sc->provider->name);
1678 me->provider_no = comp_no;
1679 me->provider_chunk = phys_chunk;
1680 me->flags |= VIRSTOR_MAP_ALLOCATED;
1682 cb = g_clone_bio(b);
1684 me->flags &= ~VIRSTOR_MAP_ALLOCATED;
1685 me->provider_no = 0;
1686 me->provider_chunk = 0;
1687 bioq_dismantle(&bq);
1688 if (b->bio_error == 0)
1689 b->bio_error = ENOMEM;
1690 g_io_deliver(b, b->bio_error);
1694 /* The allocation table is stored continuously
1695 * at the start of the drive. We need to
1696 * calculate the offset of the sector that holds
1697 * this map entry both on the drive and in the
1699 * sc_offset will end up pointing to the drive
1701 s_offset = chunk_index * sizeof *me;
1702 s_offset = (s_offset / sc->sectorsize) *
1705 /* data_me points to map entry sector
1706 * in memory (analoguos to offset) */
1707 data_me = &sc->map[(chunk_index /
1708 sc->me_per_sector) * sc->me_per_sector];
1710 /* Commit sector with map entry to storage */
1711 cb->bio_to = sc->components[0].gcons->provider;
1712 cb->bio_done = g_virstor_done;
1713 cb->bio_offset = s_offset;
1714 cb->bio_data = (char *)data_me;
1715 cb->bio_length = sc->sectorsize;
1716 cb->bio_caller1 = &sc->components[0];
1717 bioq_disksort(&bq, cb);
1720 comp = &sc->components[me->provider_no];
1721 cb = g_clone_bio(b);
1723 bioq_dismantle(&bq);
1724 if (b->bio_error == 0)
1725 b->bio_error = ENOMEM;
1726 g_io_deliver(b, b->bio_error);
1729 /* Finally, handle the data */
1730 cb->bio_to = comp->gcons->provider;
1731 cb->bio_done = g_virstor_done;
1732 cb->bio_offset = (off_t)me->provider_chunk*(off_t)chunk_size +
1734 cb->bio_length = in_chunk_length;
1735 cb->bio_data = addr;
1736 cb->bio_caller1 = comp;
1737 bioq_disksort(&bq, cb);
1739 addr += in_chunk_length;
1740 length -= in_chunk_length;
1741 offset += in_chunk_length;
1744 /* Fire off bio's here */
1746 for (cb = bioq_first(&bq); cb != NULL; cb = bioq_first(&bq)) {
1747 bioq_remove(&bq, cb);
1748 LOG_REQ(LVL_MOREDEBUG, cb, "Firing request");
1749 comp = cb->bio_caller1;
1750 cb->bio_caller1 = NULL;
1751 LOG_MSG(LVL_DEBUG, " firing bio, offset=%ju, length=%ju",
1752 cb->bio_offset, cb->bio_length);
1753 g_io_request(cb, comp->gcons);
1756 if (count == 0) { /* We handled everything locally */
1757 b->bio_completed = b->bio_length;
1764 * Allocate a chunk from a physical provider. Returns physical component,
1765 * chunk index relative to the component and the component's index.
1768 allocate_chunk(struct g_virstor_softc *sc, struct g_virstor_component **comp,
1769 u_int *comp_no_p, u_int *chunk)
1773 KASSERT(sc->curr_component < sc->n_components,
1774 ("%s: Invalid curr_component: %u", __func__, sc->curr_component));
1776 comp_no = sc->curr_component;
1777 *comp = &sc->components[comp_no];
1778 dump_component(*comp);
1779 if ((*comp)->chunk_next >= (*comp)->chunk_count) {
1780 /* This component is full. Allocate next component */
1781 if (comp_no >= sc->n_components-1) {
1782 LOG_MSG(LVL_ERROR, "All physical space allocated for %s",
1786 (*comp)->flags &= ~VIRSTOR_PROVIDER_CURRENT;
1787 sc->curr_component = ++comp_no;
1789 *comp = &sc->components[comp_no];
1790 if (comp_no >= sc->n_components - g_virstor_component_watermark-1)
1791 LOG_MSG(LVL_WARNING, "Device %s running out of components "
1792 "(switching to %u/%u: %s)", sc->geom->name,
1793 comp_no+1, sc->n_components,
1794 (*comp)->gcons->provider->name);
1795 /* Take care not to overwrite reserved chunks */
1796 if ( (*comp)->chunk_reserved > 0 &&
1797 (*comp)->chunk_next < (*comp)->chunk_reserved)
1798 (*comp)->chunk_next = (*comp)->chunk_reserved;
1801 VIRSTOR_PROVIDER_ALLOCATED | VIRSTOR_PROVIDER_CURRENT;
1802 dump_component(*comp);
1803 *comp_no_p = comp_no;
1804 *chunk = (*comp)->chunk_next++;
1806 *comp_no_p = comp_no;
1807 *chunk = (*comp)->chunk_next++;
1812 /* Dump a component */
1814 dump_component(struct g_virstor_component *comp)
1817 if (g_virstor_debug < LVL_DEBUG2)
1819 printf("Component %d: %s\n", comp->index, comp->gcons->provider->name);
1820 printf(" chunk_count: %u\n", comp->chunk_count);
1821 printf(" chunk_next: %u\n", comp->chunk_next);
1822 printf(" flags: %u\n", comp->flags);
1826 /* Dump a map entry */
1828 dump_me(struct virstor_map_entry *me, unsigned int nr)
1830 if (g_virstor_debug < LVL_DEBUG)
1832 printf("VIRT. CHUNK #%d: ", nr);
1833 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0)
1834 printf("(unallocated)\n");
1836 printf("allocated at provider %u, provider_chunk %u\n",
1837 me->provider_no, me->provider_chunk);
1842 * Dismantle bio_queue and destroy its components
1845 bioq_dismantle(struct bio_queue_head *bq)
1849 for (b = bioq_first(bq); b != NULL; b = bioq_first(bq)) {
1856 * The function that shouldn't be called.
1857 * When this is called, the stack is already garbled because of
1858 * argument mismatch. There's nothing to do now but panic, which is
1859 * accidentally the whole purpose of this function.
1860 * Motivation: to guard from accidentally calling geom methods when
1861 * they shouldn't be called. (see g_..._taste)
1866 panic("invalid_call() has just been called. Something's fishy here.");
1869 DECLARE_GEOM_CLASS(g_virstor_class, g_virstor); /* Let there be light */