2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2006-2007 Ivan Voras <ivoras@freebsd.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 /* Implementation notes:
30 * - "Components" are wrappers around providers that make up the
31 * virtual storage (i.e. a virstor has "physical" components)
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/module.h>
42 #include <sys/mutex.h>
46 #include <sys/sysctl.h>
47 #include <sys/malloc.h>
50 #include <sys/kthread.h>
51 #include <sys/mutex.h>
53 #include <geom/geom.h>
55 #include <geom/virstor/g_virstor.h>
56 #include <geom/virstor/g_virstor_md.h>
58 FEATURE(g_virstor, "GEOM virtual storage support");
60 /* Declare malloc(9) label */
61 static MALLOC_DEFINE(M_GVIRSTOR, "gvirstor", "GEOM_VIRSTOR Data");
63 /* GEOM class methods */
64 static g_init_t g_virstor_init;
65 static g_fini_t g_virstor_fini;
66 static g_taste_t g_virstor_taste;
67 static g_ctl_req_t g_virstor_config;
68 static g_ctl_destroy_geom_t g_virstor_destroy_geom;
70 /* Declare & initialize class structure ("geom class") */
71 struct g_class g_virstor_class = {
72 .name = G_VIRSTOR_CLASS_NAME,
74 .init = g_virstor_init,
75 .fini = g_virstor_fini,
76 .taste = g_virstor_taste,
77 .ctlreq = g_virstor_config,
78 .destroy_geom = g_virstor_destroy_geom
79 /* The .dumpconf and the rest are only usable for a geom instance, so
80 * they will be set when such instance is created. */
83 /* Declare sysctl's and loader tunables */
84 SYSCTL_DECL(_kern_geom);
85 static SYSCTL_NODE(_kern_geom, OID_AUTO, virstor, CTLFLAG_RW, 0,
86 "GEOM_GVIRSTOR information");
88 static u_int g_virstor_debug = 2; /* XXX: lower to 2 when released to public */
89 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, debug, CTLFLAG_RWTUN, &g_virstor_debug,
90 0, "Debug level (2=production, 5=normal, 15=excessive)");
92 static u_int g_virstor_chunk_watermark = 100;
93 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, chunk_watermark, CTLFLAG_RWTUN,
94 &g_virstor_chunk_watermark, 0,
95 "Minimum number of free chunks before issuing administrative warning");
97 static u_int g_virstor_component_watermark = 1;
98 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, component_watermark, CTLFLAG_RWTUN,
99 &g_virstor_component_watermark, 0,
100 "Minimum number of free components before issuing administrative warning");
102 static int read_metadata(struct g_consumer *, struct g_virstor_metadata *);
103 static void write_metadata(struct g_consumer *, struct g_virstor_metadata *);
104 static int clear_metadata(struct g_virstor_component *);
105 static int add_provider_to_geom(struct g_virstor_softc *, struct g_provider *,
106 struct g_virstor_metadata *);
107 static struct g_geom *create_virstor_geom(struct g_class *,
108 struct g_virstor_metadata *);
109 static void virstor_check_and_run(struct g_virstor_softc *);
110 static u_int virstor_valid_components(struct g_virstor_softc *);
111 static int virstor_geom_destroy(struct g_virstor_softc *, boolean_t,
113 static void remove_component(struct g_virstor_softc *,
114 struct g_virstor_component *, boolean_t);
115 static void bioq_dismantle(struct bio_queue_head *);
116 static int allocate_chunk(struct g_virstor_softc *,
117 struct g_virstor_component **, u_int *, u_int *);
118 static void delay_destroy_consumer(void *, int);
119 static void dump_component(struct g_virstor_component *comp);
121 static void dump_me(struct virstor_map_entry *me, unsigned int nr);
124 static void virstor_ctl_stop(struct gctl_req *, struct g_class *);
125 static void virstor_ctl_add(struct gctl_req *, struct g_class *);
126 static void virstor_ctl_remove(struct gctl_req *, struct g_class *);
127 static struct g_virstor_softc * virstor_find_geom(const struct g_class *,
129 static void update_metadata(struct g_virstor_softc *);
130 static void fill_metadata(struct g_virstor_softc *, struct g_virstor_metadata *,
133 static void g_virstor_orphan(struct g_consumer *);
134 static int g_virstor_access(struct g_provider *, int, int, int);
135 static void g_virstor_start(struct bio *);
136 static void g_virstor_dumpconf(struct sbuf *, const char *, struct g_geom *,
137 struct g_consumer *, struct g_provider *);
138 static void g_virstor_done(struct bio *);
140 static void invalid_call(void);
142 * Initialise GEOM class (per-class callback)
145 g_virstor_init(struct g_class *mp __unused)
148 /* Catch map struct size mismatch at compile time; Map entries must
149 * fit into MAXPHYS exactly, with no wasted space. */
150 CTASSERT(VIRSTOR_MAP_BLOCK_ENTRIES*VIRSTOR_MAP_ENTRY_SIZE == MAXPHYS);
152 /* Init UMA zones, TAILQ's, other global vars */
156 * Finalise GEOM class (per-class callback)
159 g_virstor_fini(struct g_class *mp __unused)
162 /* Deinit UMA zones & global vars */
166 * Config (per-class callback)
169 g_virstor_config(struct gctl_req *req, struct g_class *cp, char const *verb)
175 version = gctl_get_paraml(req, "version", sizeof(*version));
176 if (version == NULL) {
177 gctl_error(req, "Failed to get 'version' argument");
180 if (*version != G_VIRSTOR_VERSION) {
181 gctl_error(req, "Userland and kernel versions out of sync");
186 if (strcmp(verb, "add") == 0)
187 virstor_ctl_add(req, cp);
188 else if (strcmp(verb, "stop") == 0 || strcmp(verb, "destroy") == 0)
189 virstor_ctl_stop(req, cp);
190 else if (strcmp(verb, "remove") == 0)
191 virstor_ctl_remove(req, cp);
193 gctl_error(req, "unknown verb: '%s'", verb);
198 * "stop" verb from userland
201 virstor_ctl_stop(struct gctl_req *req, struct g_class *cp)
206 nargs = gctl_get_paraml(req, "nargs", sizeof *nargs);
208 gctl_error(req, "Error fetching argument '%s'", "nargs");
212 gctl_error(req, "Invalid number of arguments");
215 force = gctl_get_paraml(req, "force", sizeof *force);
217 gctl_error(req, "Error fetching argument '%s'", "force");
222 for (i = 0; i < *nargs; i++) {
225 struct g_virstor_softc *sc;
228 sprintf(param, "arg%d", i);
229 name = gctl_get_asciiparam(req, param);
231 gctl_error(req, "No 'arg%d' argument", i);
235 sc = virstor_find_geom(cp, name);
237 gctl_error(req, "Don't know anything about '%s'", name);
242 LOG_MSG(LVL_INFO, "Stopping %s by the userland command",
245 if ((error = virstor_geom_destroy(sc, TRUE, TRUE)) != 0) {
246 LOG_MSG(LVL_ERROR, "Cannot destroy %s: %d",
247 sc->geom->name, error);
254 * "add" verb from userland - add new component(s) to the structure.
255 * This will be done all at once in here, without going through the
256 * .taste function for new components.
259 virstor_ctl_add(struct gctl_req *req, struct g_class *cp)
261 /* Note: while this is going on, I/O is being done on
262 * the g_up and g_down threads. The idea is to make changes
263 * to softc members in a way that can atomically activate
264 * them all at once. */
265 struct g_virstor_softc *sc;
266 int *hardcode, *nargs;
267 const char *geom_name; /* geom to add a component to */
268 struct g_consumer *fcp;
269 struct g_virstor_bio_q *bq;
274 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
276 gctl_error(req, "Error fetching argument '%s'", "nargs");
280 gctl_error(req, "Invalid number of arguments");
283 hardcode = gctl_get_paraml(req, "hardcode", sizeof(*hardcode));
284 if (hardcode == NULL) {
285 gctl_error(req, "Error fetching argument '%s'", "hardcode");
289 /* Find "our" geom */
290 geom_name = gctl_get_asciiparam(req, "arg0");
291 if (geom_name == NULL) {
292 gctl_error(req, "Error fetching argument '%s'", "geom_name (arg0)");
295 sc = virstor_find_geom(cp, geom_name);
297 gctl_error(req, "Don't know anything about '%s'", geom_name);
301 if (virstor_valid_components(sc) != sc->n_components) {
302 LOG_MSG(LVL_ERROR, "Cannot add components to incomplete "
303 "virstor %s", sc->geom->name);
304 gctl_error(req, "Virstor %s is incomplete", sc->geom->name);
308 fcp = sc->components[0].gcons;
311 for (i = 1; i < *nargs; i++) {
312 struct g_virstor_metadata md;
314 const char *prov_name;
315 struct g_provider *pp;
316 struct g_consumer *cp;
320 snprintf(aname, sizeof aname, "arg%d", i);
321 prov_name = gctl_get_asciiparam(req, aname);
322 if (prov_name == NULL) {
323 gctl_error(req, "Error fetching argument '%s'", aname);
327 if (strncmp(prov_name, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
328 prov_name += sizeof(_PATH_DEV) - 1;
330 pp = g_provider_by_name(prov_name);
332 /* This is the most common error so be verbose about it */
334 gctl_error(req, "Invalid provider: '%s' (added"
335 " %u components)", prov_name, added);
338 gctl_error(req, "Invalid provider: '%s'",
344 cp = g_new_consumer(sc->geom);
346 gctl_error(req, "Cannot create consumer");
350 error = g_attach(cp, pp);
352 gctl_error(req, "Cannot attach a consumer to %s",
354 g_destroy_consumer(cp);
358 if (fcp->acr != 0 || fcp->acw != 0 || fcp->ace != 0) {
359 error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
361 gctl_error(req, "Access request failed for %s",
363 g_destroy_consumer(cp);
368 if (fcp->provider->sectorsize != pp->sectorsize) {
369 gctl_error(req, "Sector size doesn't fit for %s",
371 g_destroy_consumer(cp);
375 for (j = 0; j < sc->n_components; j++) {
376 if (strcmp(sc->components[j].gcons->provider->name,
378 gctl_error(req, "Component %s already in %s",
379 pp->name, sc->geom->name);
380 g_destroy_consumer(cp);
385 sc->components = realloc(sc->components,
386 sizeof(*sc->components) * (sc->n_components + 1),
387 M_GVIRSTOR, M_WAITOK);
389 nc = sc->n_components;
390 sc->components[nc].gcons = cp;
391 sc->components[nc].sc = sc;
392 sc->components[nc].index = nc;
393 sc->components[nc].chunk_count = cp->provider->mediasize /
395 sc->components[nc].chunk_next = 0;
396 sc->components[nc].chunk_reserved = 0;
398 if (sc->components[nc].chunk_count < 4) {
399 gctl_error(req, "Provider too small: %s",
401 g_destroy_consumer(cp);
405 fill_metadata(sc, &md, nc, *hardcode);
406 write_metadata(cp, &md);
407 /* The new component becomes visible when n_components is
413 /* This call to update_metadata() is critical. In case there's a
414 * power failure in the middle of it and some components are updated
415 * while others are not, there will be trouble on next .taste() iff
416 * a non-updated component is detected first */
419 LOG_MSG(LVL_INFO, "Added %d component(s) to %s", added,
421 /* Fire off BIOs previously queued because there wasn't any
422 * physical space left. If the BIOs still can't be satisfied
423 * they will again be added to the end of the queue (during
424 * which the mutex will be recursed) */
425 bq = malloc(sizeof(*bq), M_GVIRSTOR, M_WAITOK);
427 mtx_lock(&sc->delayed_bio_q_mtx);
428 /* First, insert a sentinel to the queue end, so we don't
429 * end up in an infinite loop if there's still no free
430 * space available. */
431 STAILQ_INSERT_TAIL(&sc->delayed_bio_q, bq, linkage);
432 while (!STAILQ_EMPTY(&sc->delayed_bio_q)) {
433 bq = STAILQ_FIRST(&sc->delayed_bio_q);
434 if (bq->bio != NULL) {
435 g_virstor_start(bq->bio);
436 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage);
437 free(bq, M_GVIRSTOR);
439 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage);
440 free(bq, M_GVIRSTOR);
444 mtx_unlock(&sc->delayed_bio_q_mtx);
449 * Find a geom handled by the class
451 static struct g_virstor_softc *
452 virstor_find_geom(const struct g_class *cp, const char *name)
456 LIST_FOREACH(gp, &cp->geom, geom) {
457 if (strcmp(name, gp->name) == 0)
464 * Update metadata on all components to reflect the current state
469 * Expects things to be set up so write_metadata() can work, i.e.
470 * the topology lock must be held.
473 update_metadata(struct g_virstor_softc *sc)
475 struct g_virstor_metadata md;
478 if (virstor_valid_components(sc) != sc->n_components)
479 return; /* Incomplete device */
480 LOG_MSG(LVL_DEBUG, "Updating metadata on components for %s",
482 /* Update metadata on components */
483 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__,
484 sc->geom->class->name, sc->geom->name);
486 for (n = 0; n < sc->n_components; n++) {
487 read_metadata(sc->components[n].gcons, &md);
488 md.chunk_next = sc->components[n].chunk_next;
489 md.flags = sc->components[n].flags;
490 md.md_count = sc->n_components;
491 write_metadata(sc->components[n].gcons, &md);
496 * Fills metadata (struct md) from information stored in softc and the nc'th
497 * component of virstor
500 fill_metadata(struct g_virstor_softc *sc, struct g_virstor_metadata *md,
501 u_int nc, u_int hardcode)
503 struct g_virstor_component *c;
505 bzero(md, sizeof *md);
506 c = &sc->components[nc];
508 strncpy(md->md_magic, G_VIRSTOR_MAGIC, sizeof md->md_magic);
509 md->md_version = G_VIRSTOR_VERSION;
510 strncpy(md->md_name, sc->geom->name, sizeof md->md_name);
512 md->md_virsize = sc->virsize;
513 md->md_chunk_size = sc->chunk_size;
514 md->md_count = sc->n_components;
517 strncpy(md->provider, c->gcons->provider->name,
518 sizeof md->provider);
521 md->provsize = c->gcons->provider->mediasize;
522 md->chunk_count = c->chunk_count;
523 md->chunk_next = c->chunk_next;
524 md->chunk_reserved = c->chunk_reserved;
525 md->flags = c->flags;
529 * Remove a component from virstor device.
530 * Can only be done if the component is unallocated.
533 virstor_ctl_remove(struct gctl_req *req, struct g_class *cp)
535 /* As this is executed in parallel to I/O, operations on virstor
536 * structures must be as atomic as possible. */
537 struct g_virstor_softc *sc;
539 const char *geom_name;
543 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
545 gctl_error(req, "Error fetching argument '%s'", "nargs");
549 gctl_error(req, "Invalid number of arguments");
552 /* Find "our" geom */
553 geom_name = gctl_get_asciiparam(req, "arg0");
554 if (geom_name == NULL) {
555 gctl_error(req, "Error fetching argument '%s'",
559 sc = virstor_find_geom(cp, geom_name);
561 gctl_error(req, "Don't know anything about '%s'", geom_name);
565 if (virstor_valid_components(sc) != sc->n_components) {
566 LOG_MSG(LVL_ERROR, "Cannot remove components from incomplete "
567 "virstor %s", sc->geom->name);
568 gctl_error(req, "Virstor %s is incomplete", sc->geom->name);
573 for (i = 1; i < *nargs; i++) {
575 const char *prov_name;
577 struct g_virstor_component *newcomp, *compbak;
579 sprintf(param, "arg%d", i);
580 prov_name = gctl_get_asciiparam(req, param);
581 if (prov_name == NULL) {
582 gctl_error(req, "Error fetching argument '%s'", param);
585 if (strncmp(prov_name, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
586 prov_name += sizeof(_PATH_DEV) - 1;
589 for (j = 0; j < sc->n_components; j++) {
590 if (strcmp(sc->components[j].gcons->provider->name,
597 LOG_MSG(LVL_ERROR, "No %s component in %s",
598 prov_name, sc->geom->name);
602 compbak = sc->components;
603 newcomp = malloc(sc->n_components * sizeof(*sc->components),
604 M_GVIRSTOR, M_WAITOK | M_ZERO);
605 bcopy(sc->components, newcomp, found * sizeof(*sc->components));
606 bcopy(&sc->components[found + 1], newcomp + found,
607 found * sizeof(*sc->components));
608 if ((sc->components[j].flags & VIRSTOR_PROVIDER_ALLOCATED) != 0) {
609 LOG_MSG(LVL_ERROR, "Allocated provider %s cannot be "
611 prov_name, sc->geom->name);
612 free(newcomp, M_GVIRSTOR);
613 /* We'll consider this non-fatal error */
616 /* Renumerate unallocated components */
617 for (j = 0; j < sc->n_components-1; j++) {
618 if ((sc->components[j].flags &
619 VIRSTOR_PROVIDER_ALLOCATED) == 0) {
620 sc->components[j].index = j;
623 /* This is the critical section. If a component allocation
624 * event happens while both variables are not yet set,
625 * there will be trouble. Something will panic on encountering
626 * NULL sc->components[x].gcomp member.
627 * Luckily, component allocation happens very rarely and
628 * removing components is an abnormal action in any case. */
629 sc->components = newcomp;
631 /* End critical section */
634 if (clear_metadata(&compbak[found]) != 0) {
635 LOG_MSG(LVL_WARNING, "Trouble ahead: cannot clear "
636 "metadata on %s", prov_name);
638 g_detach(compbak[found].gcons);
639 g_destroy_consumer(compbak[found].gcons);
642 free(compbak, M_GVIRSTOR);
647 /* This call to update_metadata() is critical. In case there's a
648 * power failure in the middle of it and some components are updated
649 * while others are not, there will be trouble on next .taste() iff
650 * a non-updated component is detected first */
654 LOG_MSG(LVL_INFO, "Removed %d component(s) from %s", removed,
659 * Clear metadata sector on component
662 clear_metadata(struct g_virstor_component *comp)
667 LOG_MSG(LVL_INFO, "Clearing metadata on %s",
668 comp->gcons->provider->name);
670 error = g_access(comp->gcons, 0, 1, 0);
673 buf = malloc(comp->gcons->provider->sectorsize, M_GVIRSTOR,
675 error = g_write_data(comp->gcons,
676 comp->gcons->provider->mediasize -
677 comp->gcons->provider->sectorsize,
679 comp->gcons->provider->sectorsize);
680 free(buf, M_GVIRSTOR);
681 g_access(comp->gcons, 0, -1, 0);
686 * Destroy geom forcibly.
689 g_virstor_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
692 struct g_virstor_softc *sc;
696 KASSERT(sc != NULL, ("%s: NULL sc", __func__));
699 LOG_MSG(LVL_DEBUG, "%s called for %s, sc=%p", __func__, gp->name,
710 LOG_MSG(LVL_INFO, "INVARIANTS detected");
711 LOG_MSG(LVL_INFO, "Verifying allocation "
712 "table for %s", sc->geom->name);
714 for (n = 0; n < sc->chunk_count; n++) {
715 if (sc->map[n].flags || VIRSTOR_MAP_ALLOCATED != 0)
718 LOG_MSG(LVL_INFO, "Device %s has %d allocated chunks",
719 sc->geom->name, count);
722 if (virstor_valid_components(sc) != sc->n_components) {
723 /* This is a incomplete virstor device (not all
724 * components have been found) */
725 LOG_MSG(LVL_ERROR, "Device %s is incomplete",
729 error = g_access(sc->components[0].gcons, 1, 0, 0);
730 KASSERT(error == 0, ("%s: g_access failed (%d)", __func__,
732 /* Compare the whole on-disk allocation table with what's
733 * currently in memory */
734 while (n < sc->chunk_count) {
735 buf = g_read_data(sc->components[0].gcons, off,
736 sc->sectorsize, &error);
737 KASSERT(buf != NULL, ("g_read_data returned NULL (%d) "
738 "for read at %jd", error, off));
739 if (bcmp(buf, &sc->map[n], sc->sectorsize) != 0) {
740 LOG_MSG(LVL_ERROR, "ERROR in allocation table, "
741 "entry %d, offset %jd", n, off);
745 n += sc->me_per_sector;
746 off += sc->sectorsize;
749 error = g_access(sc->components[0].gcons, -1, 0, 0);
750 KASSERT(error == 0, ("%s: g_access failed (%d) on exit",
753 LOG_MSG(LVL_ERROR, "ALLOCATION TABLE CORRUPTED FOR %s "
754 "(%d sectors don't match, max %zu allocations)",
755 sc->geom->name, count,
756 count * sc->me_per_sector);
758 LOG_MSG(LVL_INFO, "Allocation table ok for %s",
764 virstor_geom_destroy(sc, FALSE, FALSE);
772 * Taste event (per-class callback)
773 * Examines a provider and creates geom instances if needed
775 static struct g_geom *
776 g_virstor_taste(struct g_class *mp, struct g_provider *pp, int flags)
778 struct g_virstor_metadata md;
780 struct g_consumer *cp;
781 struct g_virstor_softc *sc;
784 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
786 LOG_MSG(LVL_DEBUG, "Tasting %s", pp->name);
788 /* We need a dummy geom to attach a consumer to the given provider */
789 gp = g_new_geomf(mp, "virstor:taste.helper");
790 gp->start = (void *)invalid_call; /* XXX: hacked up so the */
791 gp->access = (void *)invalid_call; /* compiler doesn't complain. */
792 gp->orphan = (void *)invalid_call; /* I really want these to fail. */
794 cp = g_new_consumer(gp);
796 error = read_metadata(cp, &md);
798 g_destroy_consumer(cp);
804 if (strcmp(md.md_magic, G_VIRSTOR_MAGIC) != 0)
806 if (md.md_version != G_VIRSTOR_VERSION) {
807 LOG_MSG(LVL_ERROR, "Kernel module version invalid "
808 "to handle %s (%s) : %d should be %d",
809 md.md_name, pp->name, md.md_version, G_VIRSTOR_VERSION);
812 if (md.provsize != pp->mediasize)
815 /* If the provider name is hardcoded, use the offered provider only
816 * if it's been offered with its proper name (the one used in
817 * the label command). */
818 if (md.provider[0] != '\0' &&
819 !g_compare_names(md.provider, pp->name))
822 /* Iterate all geoms this class already knows about to see if a new
823 * geom instance of this class needs to be created (in case the provider
824 * is first from a (possibly) multi-consumer geom) or it just needs
825 * to be added to an existing instance. */
828 LIST_FOREACH(gp, &mp->geom, geom) {
832 if (strcmp(md.md_name, sc->geom->name) != 0)
834 if (md.md_id != sc->id)
838 if (gp != NULL) { /* We found an existing geom instance; add to it */
839 LOG_MSG(LVL_INFO, "Adding %s to %s", pp->name, md.md_name);
840 error = add_provider_to_geom(sc, pp, &md);
842 LOG_MSG(LVL_ERROR, "Error adding %s to %s (error %d)",
843 pp->name, md.md_name, error);
846 } else { /* New geom instance needs to be created */
847 gp = create_virstor_geom(mp, &md);
849 LOG_MSG(LVL_ERROR, "Error creating new instance of "
850 "class %s: %s", mp->name, md.md_name);
851 LOG_MSG(LVL_DEBUG, "Error creating %s at %s",
852 md.md_name, pp->name);
856 LOG_MSG(LVL_INFO, "Adding %s to %s (first found)", pp->name,
858 error = add_provider_to_geom(sc, pp, &md);
860 LOG_MSG(LVL_ERROR, "Error adding %s to %s (error %d)",
861 pp->name, md.md_name, error);
862 virstor_geom_destroy(sc, TRUE, FALSE);
871 * Destroyes consumer passed to it in arguments. Used as a callback
875 delay_destroy_consumer(void *arg, int flags __unused)
877 struct g_consumer *c = arg;
878 KASSERT(c != NULL, ("%s: invalid consumer", __func__));
879 LOG_MSG(LVL_DEBUG, "Consumer %s destroyed with delay",
882 g_destroy_consumer(c);
886 * Remove a component (consumer) from geom instance; If it's the first
887 * component being removed, orphan the provider to announce geom's being
891 remove_component(struct g_virstor_softc *sc, struct g_virstor_component *comp,
894 struct g_consumer *c;
896 KASSERT(comp->gcons != NULL, ("Component with no consumer in %s",
901 KASSERT(c->provider != NULL, ("%s: no provider", __func__));
902 LOG_MSG(LVL_DEBUG, "Component %s removed from %s", c->provider->name,
904 if (sc->provider != NULL) {
905 LOG_MSG(LVL_INFO, "Removing provider %s", sc->provider->name);
906 g_wither_provider(sc->provider, ENXIO);
910 if (c->acr > 0 || c->acw > 0 || c->ace > 0)
911 g_access(c, -c->acr, -c->acw, -c->ace);
913 /* Destroy consumer after it's tasted */
914 g_post_event(delay_destroy_consumer, c, M_WAITOK, NULL);
917 g_destroy_consumer(c);
922 * Destroy geom - called internally
923 * See g_virstor_destroy_geom for the other one
926 virstor_geom_destroy(struct g_virstor_softc *sc, boolean_t force,
929 struct g_provider *pp;
939 if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
940 LOG_MSG(force ? LVL_WARNING : LVL_ERROR,
941 "Device %s is still open.", pp->name);
946 for (n = 0; n < sc->n_components; n++) {
947 if (sc->components[n].gcons != NULL)
948 remove_component(sc, &sc->components[n], delay);
954 KASSERT(sc->provider == NULL, ("Provider still exists for %s",
957 /* XXX: This might or might not work, since we're called with
958 * the topology lock held. Also, it might panic the kernel if
959 * the error'd BIO is in softupdates code. */
960 mtx_lock(&sc->delayed_bio_q_mtx);
961 while (!STAILQ_EMPTY(&sc->delayed_bio_q)) {
962 struct g_virstor_bio_q *bq;
963 bq = STAILQ_FIRST(&sc->delayed_bio_q);
964 bq->bio->bio_error = ENOSPC;
965 g_io_deliver(bq->bio, EIO);
966 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage);
967 free(bq, M_GVIRSTOR);
969 mtx_unlock(&sc->delayed_bio_q_mtx);
970 mtx_destroy(&sc->delayed_bio_q_mtx);
972 free(sc->map, M_GVIRSTOR);
973 free(sc->components, M_GVIRSTOR);
974 bzero(sc, sizeof *sc);
975 free(sc, M_GVIRSTOR);
977 pp = LIST_FIRST(&gp->provider); /* We only offer one provider */
978 if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
979 LOG_MSG(LVL_DEBUG, "Device %s destroyed", gp->name);
981 g_wither_geom(gp, ENXIO);
987 * Utility function: read metadata & decode. Wants topology lock to be
991 read_metadata(struct g_consumer *cp, struct g_virstor_metadata *md)
993 struct g_provider *pp;
998 error = g_access(cp, 1, 0, 0);
1002 g_topology_unlock();
1003 buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
1006 g_access(cp, -1, 0, 0);
1010 virstor_metadata_decode(buf, md);
1017 * Utility function: encode & write metadata. Assumes topology lock is
1020 * There is no useful way of recovering from errors in this function,
1021 * not involving panicking the kernel. If the metadata cannot be written
1022 * the most we can do is notify the operator and hope he spots it and
1023 * replaces the broken drive.
1026 write_metadata(struct g_consumer *cp, struct g_virstor_metadata *md)
1028 struct g_provider *pp;
1032 KASSERT(cp != NULL && md != NULL && cp->provider != NULL,
1033 ("Something's fishy in %s", __func__));
1034 LOG_MSG(LVL_DEBUG, "Writing metadata on %s", cp->provider->name);
1035 g_topology_assert();
1036 error = g_access(cp, 0, 1, 0);
1038 LOG_MSG(LVL_ERROR, "g_access(0,1,0) failed for %s: %d",
1039 cp->provider->name, error);
1044 buf = malloc(pp->sectorsize, M_GVIRSTOR, M_WAITOK);
1045 bzero(buf, pp->sectorsize);
1046 virstor_metadata_encode(md, buf);
1047 g_topology_unlock();
1048 error = g_write_data(cp, pp->mediasize - pp->sectorsize, buf,
1051 g_access(cp, 0, -1, 0);
1052 free(buf, M_GVIRSTOR);
1055 LOG_MSG(LVL_ERROR, "Error %d writing metadata to %s",
1056 error, cp->provider->name);
1060 * Creates a new instance of this GEOM class, initialise softc
1062 static struct g_geom *
1063 create_virstor_geom(struct g_class *mp, struct g_virstor_metadata *md)
1066 struct g_virstor_softc *sc;
1068 LOG_MSG(LVL_DEBUG, "Creating geom instance for %s (id=%u)",
1069 md->md_name, md->md_id);
1071 if (md->md_count < 1 || md->md_chunk_size < 1 ||
1072 md->md_virsize < md->md_chunk_size) {
1073 /* This is bogus configuration, and probably means data is
1074 * somehow corrupted. Panic, maybe? */
1075 LOG_MSG(LVL_ERROR, "Nonsensical metadata information for %s",
1080 /* Check if it's already created */
1081 LIST_FOREACH(gp, &mp->geom, geom) {
1083 if (sc != NULL && strcmp(sc->geom->name, md->md_name) == 0) {
1084 LOG_MSG(LVL_WARNING, "Geom %s already exists",
1086 if (sc->id != md->md_id) {
1088 "Some stale or invalid components "
1089 "exist for virstor device named %s. "
1090 "You will need to <CLEAR> all stale "
1091 "components and maybe reconfigure "
1092 "the virstor device. Tune "
1093 "kern.geom.virstor.debug sysctl up "
1094 "for more information.",
1100 gp = g_new_geomf(mp, "%s", md->md_name);
1101 gp->softc = NULL; /* to circumevent races that test softc */
1103 gp->start = g_virstor_start;
1104 gp->spoiled = g_virstor_orphan;
1105 gp->orphan = g_virstor_orphan;
1106 gp->access = g_virstor_access;
1107 gp->dumpconf = g_virstor_dumpconf;
1109 sc = malloc(sizeof(*sc), M_GVIRSTOR, M_WAITOK | M_ZERO);
1111 sc->n_components = md->md_count;
1112 sc->components = malloc(sizeof(struct g_virstor_component) * md->md_count,
1113 M_GVIRSTOR, M_WAITOK | M_ZERO);
1114 sc->chunk_size = md->md_chunk_size;
1115 sc->virsize = md->md_virsize;
1116 STAILQ_INIT(&sc->delayed_bio_q);
1117 mtx_init(&sc->delayed_bio_q_mtx, "gvirstor_delayed_bio_q_mtx",
1118 "gvirstor", MTX_DEF | MTX_RECURSE);
1121 sc->provider = NULL; /* virstor_check_and_run will create it */
1124 LOG_MSG(LVL_ANNOUNCE, "Device %s created", sc->geom->name);
1130 * Add provider to a GEOM class instance
1133 add_provider_to_geom(struct g_virstor_softc *sc, struct g_provider *pp,
1134 struct g_virstor_metadata *md)
1136 struct g_virstor_component *component;
1137 struct g_consumer *cp, *fcp;
1141 if (md->no >= sc->n_components)
1144 /* "Current" compontent */
1145 component = &(sc->components[md->no]);
1146 if (component->gcons != NULL)
1150 fcp = LIST_FIRST(&gp->consumer);
1152 cp = g_new_consumer(gp);
1153 error = g_attach(cp, pp);
1156 g_destroy_consumer(cp);
1161 if (fcp->provider->sectorsize != pp->sectorsize) {
1162 /* TODO: this can be made to work */
1163 LOG_MSG(LVL_ERROR, "Provider %s of %s has invalid "
1164 "sector size (%d)", pp->name, sc->geom->name,
1168 if (fcp->acr > 0 || fcp->acw || fcp->ace > 0) {
1169 /* Replicate access permissions from first "live" consumer
1171 error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
1174 g_destroy_consumer(cp);
1180 /* Bring up a new component */
1181 cp->private = component;
1182 component->gcons = cp;
1184 component->index = md->no;
1185 component->chunk_count = md->chunk_count;
1186 component->chunk_next = md->chunk_next;
1187 component->chunk_reserved = md->chunk_reserved;
1188 component->flags = md->flags;
1190 LOG_MSG(LVL_DEBUG, "%s attached to %s", pp->name, sc->geom->name);
1192 virstor_check_and_run(sc);
1197 * Check if everything's ready to create the geom provider & device entry,
1198 * create and start provider.
1199 * Called ultimately by .taste, from g_event thread
1202 virstor_check_and_run(struct g_virstor_softc *sc)
1209 if (virstor_valid_components(sc) != sc->n_components)
1212 if (virstor_valid_components(sc) == 0) {
1213 /* This is actually a candidate for panic() */
1214 LOG_MSG(LVL_ERROR, "No valid components for %s?",
1215 sc->provider->name);
1219 sc->sectorsize = sc->components[0].gcons->provider->sectorsize;
1221 /* Initialise allocation map from the first consumer */
1222 sc->chunk_count = sc->virsize / sc->chunk_size;
1223 if (sc->chunk_count * (off_t)sc->chunk_size != sc->virsize) {
1224 LOG_MSG(LVL_WARNING, "Device %s truncated to %ju bytes",
1226 sc->chunk_count * (off_t)sc->chunk_size);
1228 sc->map_size = sc->chunk_count * sizeof *(sc->map);
1229 /* The following allocation is in order of 4MB - 8MB */
1230 sc->map = malloc(sc->map_size, M_GVIRSTOR, M_WAITOK);
1231 KASSERT(sc->map != NULL, ("%s: Memory allocation error (%zu bytes) for %s",
1232 __func__, sc->map_size, sc->provider->name));
1233 sc->map_sectors = sc->map_size / sc->sectorsize;
1236 for (n = 0; n < sc->n_components; n++)
1237 count += sc->components[n].chunk_count;
1238 LOG_MSG(LVL_INFO, "Device %s has %zu physical chunks and %zu virtual "
1240 sc->geom->name, count, sc->chunk_count, sc->chunk_size / 1024);
1242 error = g_access(sc->components[0].gcons, 1, 0, 0);
1244 LOG_MSG(LVL_ERROR, "Cannot acquire read access for %s to "
1245 "read allocation map for %s",
1246 sc->components[0].gcons->provider->name,
1250 /* Read in the allocation map */
1251 LOG_MSG(LVL_DEBUG, "Reading map for %s from %s", sc->geom->name,
1252 sc->components[0].gcons->provider->name);
1253 off = count = n = 0;
1254 while (count < sc->map_size) {
1255 struct g_virstor_map_entry *mapbuf;
1258 bs = MIN(MAXPHYS, sc->map_size - count);
1259 if (bs % sc->sectorsize != 0) {
1260 /* Check for alignment errors */
1261 bs = rounddown(bs, sc->sectorsize);
1264 LOG_MSG(LVL_ERROR, "Trouble: map is not sector-aligned "
1265 "for %s on %s", sc->geom->name,
1266 sc->components[0].gcons->provider->name);
1268 mapbuf = g_read_data(sc->components[0].gcons, off, bs, &error);
1269 if (mapbuf == NULL) {
1270 free(sc->map, M_GVIRSTOR);
1271 LOG_MSG(LVL_ERROR, "Error reading allocation map "
1272 "for %s from %s (offset %ju) (error %d)",
1274 sc->components[0].gcons->provider->name,
1279 bcopy(mapbuf, &sc->map[n], bs);
1282 n += bs / sizeof *(sc->map);
1285 g_access(sc->components[0].gcons, -1, 0, 0);
1286 LOG_MSG(LVL_DEBUG, "Read map for %s", sc->geom->name);
1288 /* find first component with allocatable chunks */
1290 for (n = 0; n < sc->n_components; n++) {
1291 if (sc->components[n].chunk_next <
1292 sc->components[n].chunk_count) {
1298 /* not found? set it to the last component and handle it
1300 index = sc->n_components - 1;
1302 if (index >= sc->n_components - g_virstor_component_watermark - 1) {
1303 LOG_MSG(LVL_WARNING, "Device %s running out of components "
1304 "(%d/%u: %s)", sc->geom->name,
1307 sc->components[index].gcons->provider->name);
1309 sc->curr_component = index;
1311 if (sc->components[index].chunk_next >=
1312 sc->components[index].chunk_count - g_virstor_chunk_watermark) {
1313 LOG_MSG(LVL_WARNING,
1314 "Component %s of %s is running out of free space "
1316 sc->components[index].gcons->provider->name,
1317 sc->geom->name, sc->components[index].chunk_count -
1318 sc->components[index].chunk_next);
1321 sc->me_per_sector = sc->sectorsize / sizeof *(sc->map);
1322 if (sc->sectorsize % sizeof *(sc->map) != 0) {
1324 "%s: Map entries don't fit exactly in a sector (%s)",
1325 __func__, sc->geom->name);
1329 /* Recalculate allocated chunks in components & at the same time
1330 * verify map data is sane. We could trust metadata on this, but
1331 * we want to make sure. */
1332 for (n = 0; n < sc->n_components; n++)
1333 sc->components[n].chunk_next = sc->components[n].chunk_reserved;
1335 for (n = 0; n < sc->chunk_count; n++) {
1336 if (sc->map[n].provider_no >= sc->n_components ||
1337 sc->map[n].provider_chunk >=
1338 sc->components[sc->map[n].provider_no].chunk_count) {
1339 LOG_MSG(LVL_ERROR, "%s: Invalid entry %u in map for %s",
1340 __func__, (u_int)n, sc->geom->name);
1341 LOG_MSG(LVL_ERROR, "%s: provider_no: %u, n_components: %u"
1342 " provider_chunk: %u, chunk_count: %u", __func__,
1343 sc->map[n].provider_no, sc->n_components,
1344 sc->map[n].provider_chunk,
1345 sc->components[sc->map[n].provider_no].chunk_count);
1348 if (sc->map[n].flags & VIRSTOR_MAP_ALLOCATED)
1349 sc->components[sc->map[n].provider_no].chunk_next++;
1352 sc->provider = g_new_providerf(sc->geom, "virstor/%s",
1355 sc->provider->sectorsize = sc->sectorsize;
1356 sc->provider->mediasize = sc->virsize;
1357 g_error_provider(sc->provider, 0);
1359 LOG_MSG(LVL_INFO, "%s activated", sc->provider->name);
1360 LOG_MSG(LVL_DEBUG, "%s starting with current component %u, starting "
1361 "chunk %u", sc->provider->name, sc->curr_component,
1362 sc->components[sc->curr_component].chunk_next);
1366 * Returns count of active providers in this geom instance
1369 virstor_valid_components(struct g_virstor_softc *sc)
1374 KASSERT(sc != NULL, ("%s: softc is NULL", __func__));
1375 KASSERT(sc->components != NULL, ("%s: sc->components is NULL", __func__));
1376 for (i = 0; i < sc->n_components; i++)
1377 if (sc->components[i].gcons != NULL)
1383 * Called when the consumer gets orphaned (?)
1386 g_virstor_orphan(struct g_consumer *cp)
1388 struct g_virstor_softc *sc;
1389 struct g_virstor_component *comp;
1392 g_topology_assert();
1399 KASSERT(comp != NULL, ("%s: No component in private part of consumer",
1401 remove_component(sc, comp, FALSE);
1402 if (virstor_valid_components(sc) == 0)
1403 virstor_geom_destroy(sc, TRUE, FALSE);
1407 * Called to notify geom when it's been opened, and for what intent
1410 g_virstor_access(struct g_provider *pp, int dr, int dw, int de)
1412 struct g_consumer *c;
1413 struct g_virstor_softc *sc;
1417 KASSERT(pp != NULL, ("%s: NULL provider", __func__));
1419 KASSERT(gp != NULL, ("%s: NULL geom", __func__));
1423 /* It seems that .access can be called with negative dr,dw,dx
1424 * in this case but I want to check for myself */
1425 LOG_MSG(LVL_WARNING, "access(%d, %d, %d) for %s",
1426 dr, dw, de, pp->name);
1427 /* This should only happen when geom is withered so
1428 * allow only negative requests */
1429 KASSERT(dr <= 0 && dw <= 0 && de <= 0,
1430 ("%s: Positive access for %s", __func__, pp->name));
1431 if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0)
1432 LOG_MSG(LVL_DEBUG, "Device %s definitely destroyed",
1437 /* Grab an exclusive bit to propagate on our consumers on first open */
1438 if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)
1440 /* ... drop it on close */
1441 if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0) {
1443 update_metadata(sc); /* Writes statistical information */
1447 LIST_FOREACH(c, &gp->consumer, consumer) {
1448 KASSERT(c != NULL, ("%s: consumer is NULL", __func__));
1449 error = g_access(c, dr, dw, de);
1451 struct g_consumer *c2;
1453 /* Backout earlier changes */
1454 LIST_FOREACH(c2, &gp->consumer, consumer) {
1455 if (c2 == c) /* all eariler components fixed */
1457 g_access(c2, -dr, -dw, -de);
1466 * Generate XML dump of current state
1469 g_virstor_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1470 struct g_consumer *cp, struct g_provider *pp)
1472 struct g_virstor_softc *sc;
1474 g_topology_assert();
1477 if (sc == NULL || pp != NULL)
1481 /* For each component */
1482 struct g_virstor_component *comp;
1487 sbuf_printf(sb, "%s<ComponentIndex>%u</ComponentIndex>\n",
1488 indent, comp->index);
1489 sbuf_printf(sb, "%s<ChunkCount>%u</ChunkCount>\n",
1490 indent, comp->chunk_count);
1491 sbuf_printf(sb, "%s<ChunksUsed>%u</ChunksUsed>\n",
1492 indent, comp->chunk_next);
1493 sbuf_printf(sb, "%s<ChunksReserved>%u</ChunksReserved>\n",
1494 indent, comp->chunk_reserved);
1495 sbuf_printf(sb, "%s<StorageFree>%u%%</StorageFree>\n",
1497 comp->chunk_next > 0 ? 100 -
1498 ((comp->chunk_next + comp->chunk_reserved) * 100) /
1499 comp->chunk_count : 100);
1501 /* For the whole thing */
1502 u_int count, used, i;
1505 count = used = size = 0;
1506 for (i = 0; i < sc->n_components; i++) {
1507 if (sc->components[i].gcons != NULL) {
1508 count += sc->components[i].chunk_count;
1509 used += sc->components[i].chunk_next +
1510 sc->components[i].chunk_reserved;
1511 size += sc->components[i].gcons->
1512 provider->mediasize;
1516 sbuf_printf(sb, "%s<Status>"
1517 "Components=%u, Online=%u</Status>\n", indent,
1518 sc->n_components, virstor_valid_components(sc));
1519 sbuf_printf(sb, "%s<State>%u%% physical free</State>\n",
1520 indent, 100-(used * 100) / count);
1521 sbuf_printf(sb, "%s<ChunkSize>%zu</ChunkSize>\n", indent,
1523 sbuf_printf(sb, "%s<PhysicalFree>%u%%</PhysicalFree>\n",
1524 indent, used > 0 ? 100 - (used * 100) / count : 100);
1525 sbuf_printf(sb, "%s<ChunkPhysicalCount>%u</ChunkPhysicalCount>\n",
1527 sbuf_printf(sb, "%s<ChunkVirtualCount>%zu</ChunkVirtualCount>\n",
1528 indent, sc->chunk_count);
1529 sbuf_printf(sb, "%s<PhysicalBacking>%zu%%</PhysicalBacking>\n",
1531 (count * 100) / sc->chunk_count);
1532 sbuf_printf(sb, "%s<PhysicalBackingSize>%jd</PhysicalBackingSize>\n",
1534 sbuf_printf(sb, "%s<VirtualSize>%jd</VirtualSize>\n", indent,
1540 * GEOM .done handler
1541 * Can't use standard handler because one requested IO may
1542 * fork into additional data IOs
1545 g_virstor_done(struct bio *b)
1547 struct g_virstor_softc *sc;
1548 struct bio *parent_b;
1550 parent_b = b->bio_parent;
1551 sc = parent_b->bio_to->geom->softc;
1553 if (b->bio_error != 0) {
1554 LOG_MSG(LVL_ERROR, "Error %d for offset=%ju, length=%ju, %s",
1555 b->bio_error, b->bio_offset, b->bio_length,
1557 if (parent_b->bio_error == 0)
1558 parent_b->bio_error = b->bio_error;
1561 parent_b->bio_inbed++;
1562 parent_b->bio_completed += b->bio_completed;
1564 if (parent_b->bio_children == parent_b->bio_inbed) {
1565 parent_b->bio_completed = parent_b->bio_length;
1566 g_io_deliver(parent_b, parent_b->bio_error);
1573 * Called in g_down thread
1576 g_virstor_start(struct bio *b)
1578 struct g_virstor_softc *sc;
1579 struct g_virstor_component *comp;
1581 struct g_provider *pp;
1583 off_t offset, length;
1584 struct bio_queue_head bq;
1585 size_t chunk_size; /* cached for convenience */
1589 sc = pp->geom->softc;
1590 KASSERT(sc != NULL, ("%s: no softc (error=%d, device=%s)", __func__,
1591 b->bio_to->error, b->bio_to->name));
1593 LOG_REQ(LVL_MOREDEBUG, b, "%s", __func__);
1595 switch (b->bio_cmd) {
1601 g_io_deliver(b, EOPNOTSUPP);
1605 LOG_MSG(LVL_DEBUG2, "BIO arrived, size=%ju", b->bio_length);
1608 chunk_size = sc->chunk_size;
1610 offset = b->bio_offset; /* virtual offset and length */
1611 length = b->bio_length;
1613 while (length > 0) {
1614 size_t chunk_index, in_chunk_offset, in_chunk_length;
1615 struct virstor_map_entry *me;
1617 chunk_index = offset / chunk_size; /* round downwards */
1618 in_chunk_offset = offset % chunk_size;
1619 in_chunk_length = min(length, chunk_size - in_chunk_offset);
1620 LOG_MSG(LVL_DEBUG, "Mapped %s(%ju, %ju) to (%zu,%zu,%zu)",
1621 b->bio_cmd == BIO_READ ? "R" : "W",
1623 chunk_index, in_chunk_offset, in_chunk_length);
1624 me = &sc->map[chunk_index];
1626 if (b->bio_cmd == BIO_READ || b->bio_cmd == BIO_DELETE) {
1627 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) {
1628 /* Reads from unallocated chunks return zeroed
1630 if (b->bio_cmd == BIO_READ)
1631 bzero(addr, in_chunk_length);
1633 comp = &sc->components[me->provider_no];
1635 cb = g_clone_bio(b);
1637 bioq_dismantle(&bq);
1638 if (b->bio_error == 0)
1639 b->bio_error = ENOMEM;
1640 g_io_deliver(b, b->bio_error);
1643 cb->bio_to = comp->gcons->provider;
1644 cb->bio_done = g_virstor_done;
1646 (off_t)me->provider_chunk * (off_t)chunk_size
1648 cb->bio_length = in_chunk_length;
1649 cb->bio_data = addr;
1650 cb->bio_caller1 = comp;
1651 bioq_disksort(&bq, cb);
1653 } else { /* handle BIO_WRITE */
1654 KASSERT(b->bio_cmd == BIO_WRITE,
1655 ("%s: Unknown command %d", __func__,
1658 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) {
1659 /* We have a virtual chunk, represented by
1660 * the "me" entry, but it's not yet allocated
1661 * (tied to) a physical chunk. So do it now. */
1662 struct virstor_map_entry *data_me;
1663 u_int phys_chunk, comp_no;
1667 error = allocate_chunk(sc, &comp, &comp_no,
1670 /* We cannot allocate a physical chunk
1671 * to satisfy this request, so we'll
1672 * delay it to when we can...
1673 * XXX: this will prevent the fs from
1674 * being umounted! */
1675 struct g_virstor_bio_q *biq;
1676 biq = malloc(sizeof *biq, M_GVIRSTOR,
1679 bioq_dismantle(&bq);
1680 if (b->bio_error == 0)
1681 b->bio_error = ENOMEM;
1682 g_io_deliver(b, b->bio_error);
1686 mtx_lock(&sc->delayed_bio_q_mtx);
1687 STAILQ_INSERT_TAIL(&sc->delayed_bio_q,
1689 mtx_unlock(&sc->delayed_bio_q_mtx);
1690 LOG_MSG(LVL_WARNING, "Delaying BIO "
1691 "(size=%ju) until free physical "
1692 "space can be found on %s",
1694 sc->provider->name);
1697 LOG_MSG(LVL_DEBUG, "Allocated chunk %u on %s "
1700 comp->gcons->provider->name,
1701 sc->provider->name);
1703 me->provider_no = comp_no;
1704 me->provider_chunk = phys_chunk;
1705 me->flags |= VIRSTOR_MAP_ALLOCATED;
1707 cb = g_clone_bio(b);
1709 me->flags &= ~VIRSTOR_MAP_ALLOCATED;
1710 me->provider_no = 0;
1711 me->provider_chunk = 0;
1712 bioq_dismantle(&bq);
1713 if (b->bio_error == 0)
1714 b->bio_error = ENOMEM;
1715 g_io_deliver(b, b->bio_error);
1719 /* The allocation table is stored continuously
1720 * at the start of the drive. We need to
1721 * calculate the offset of the sector that holds
1722 * this map entry both on the drive and in the
1724 * sc_offset will end up pointing to the drive
1726 s_offset = chunk_index * sizeof *me;
1727 s_offset = rounddown(s_offset, sc->sectorsize);
1729 /* data_me points to map entry sector
1730 * in memory (analogous to offset) */
1731 data_me = &sc->map[rounddown(chunk_index,
1732 sc->me_per_sector)];
1734 /* Commit sector with map entry to storage */
1735 cb->bio_to = sc->components[0].gcons->provider;
1736 cb->bio_done = g_virstor_done;
1737 cb->bio_offset = s_offset;
1738 cb->bio_data = (char *)data_me;
1739 cb->bio_length = sc->sectorsize;
1740 cb->bio_caller1 = &sc->components[0];
1741 bioq_disksort(&bq, cb);
1744 comp = &sc->components[me->provider_no];
1745 cb = g_clone_bio(b);
1747 bioq_dismantle(&bq);
1748 if (b->bio_error == 0)
1749 b->bio_error = ENOMEM;
1750 g_io_deliver(b, b->bio_error);
1753 /* Finally, handle the data */
1754 cb->bio_to = comp->gcons->provider;
1755 cb->bio_done = g_virstor_done;
1756 cb->bio_offset = (off_t)me->provider_chunk*(off_t)chunk_size +
1758 cb->bio_length = in_chunk_length;
1759 cb->bio_data = addr;
1760 cb->bio_caller1 = comp;
1761 bioq_disksort(&bq, cb);
1763 addr += in_chunk_length;
1764 length -= in_chunk_length;
1765 offset += in_chunk_length;
1768 /* Fire off bio's here */
1770 for (cb = bioq_first(&bq); cb != NULL; cb = bioq_first(&bq)) {
1771 bioq_remove(&bq, cb);
1772 LOG_REQ(LVL_MOREDEBUG, cb, "Firing request");
1773 comp = cb->bio_caller1;
1774 cb->bio_caller1 = NULL;
1775 LOG_MSG(LVL_DEBUG, " firing bio, offset=%ju, length=%ju",
1776 cb->bio_offset, cb->bio_length);
1777 g_io_request(cb, comp->gcons);
1780 if (count == 0) { /* We handled everything locally */
1781 b->bio_completed = b->bio_length;
1788 * Allocate a chunk from a physical provider. Returns physical component,
1789 * chunk index relative to the component and the component's index.
1792 allocate_chunk(struct g_virstor_softc *sc, struct g_virstor_component **comp,
1793 u_int *comp_no_p, u_int *chunk)
1797 KASSERT(sc->curr_component < sc->n_components,
1798 ("%s: Invalid curr_component: %u", __func__, sc->curr_component));
1800 comp_no = sc->curr_component;
1801 *comp = &sc->components[comp_no];
1802 dump_component(*comp);
1803 if ((*comp)->chunk_next >= (*comp)->chunk_count) {
1804 /* This component is full. Allocate next component */
1805 if (comp_no >= sc->n_components-1) {
1806 LOG_MSG(LVL_ERROR, "All physical space allocated for %s",
1810 (*comp)->flags &= ~VIRSTOR_PROVIDER_CURRENT;
1811 sc->curr_component = ++comp_no;
1813 *comp = &sc->components[comp_no];
1814 if (comp_no >= sc->n_components - g_virstor_component_watermark-1)
1815 LOG_MSG(LVL_WARNING, "Device %s running out of components "
1816 "(switching to %u/%u: %s)", sc->geom->name,
1817 comp_no+1, sc->n_components,
1818 (*comp)->gcons->provider->name);
1819 /* Take care not to overwrite reserved chunks */
1820 if ( (*comp)->chunk_reserved > 0 &&
1821 (*comp)->chunk_next < (*comp)->chunk_reserved)
1822 (*comp)->chunk_next = (*comp)->chunk_reserved;
1825 VIRSTOR_PROVIDER_ALLOCATED | VIRSTOR_PROVIDER_CURRENT;
1826 dump_component(*comp);
1827 *comp_no_p = comp_no;
1828 *chunk = (*comp)->chunk_next++;
1830 *comp_no_p = comp_no;
1831 *chunk = (*comp)->chunk_next++;
1836 /* Dump a component */
1838 dump_component(struct g_virstor_component *comp)
1841 if (g_virstor_debug < LVL_DEBUG2)
1843 printf("Component %d: %s\n", comp->index, comp->gcons->provider->name);
1844 printf(" chunk_count: %u\n", comp->chunk_count);
1845 printf(" chunk_next: %u\n", comp->chunk_next);
1846 printf(" flags: %u\n", comp->flags);
1850 /* Dump a map entry */
1852 dump_me(struct virstor_map_entry *me, unsigned int nr)
1854 if (g_virstor_debug < LVL_DEBUG)
1856 printf("VIRT. CHUNK #%d: ", nr);
1857 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0)
1858 printf("(unallocated)\n");
1860 printf("allocated at provider %u, provider_chunk %u\n",
1861 me->provider_no, me->provider_chunk);
1866 * Dismantle bio_queue and destroy its components
1869 bioq_dismantle(struct bio_queue_head *bq)
1873 for (b = bioq_first(bq); b != NULL; b = bioq_first(bq)) {
1880 * The function that shouldn't be called.
1881 * When this is called, the stack is already garbled because of
1882 * argument mismatch. There's nothing to do now but panic, which is
1883 * accidentally the whole purpose of this function.
1884 * Motivation: to guard from accidentally calling geom methods when
1885 * they shouldn't be called. (see g_..._taste)
1890 panic("invalid_call() has just been called. Something's fishy here.");
1893 DECLARE_GEOM_CLASS(g_virstor_class, g_virstor); /* Let there be light */
1894 MODULE_VERSION(geom_virstor, 0);