/*- * Copyright (c) 2002 Poul-Henning Kamp * Copyright (c) 2002 Networks Associates Technology, Inc. * Copyright (c) 2013 The FreeBSD Foundation * All rights reserved. * * This software was developed for the FreeBSD Project by Poul-Henning Kamp * and NAI Labs, the Security Research Division of Network Associates, Inc. * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the * DARPA CHATS research program. * * Portions of this software were developed by Konstantin Belousov * under sponsorship from the FreeBSD Foundation. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The names of the authors may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static int g_io_transient_map_bio(struct bio *bp); static struct g_bioq g_bio_run_down; static struct g_bioq g_bio_run_up; static struct g_bioq g_bio_run_task; /* * Pace is a hint that we've had some trouble recently allocating * bios, so we should back off trying to send I/O down the stack * a bit to let the problem resolve. When pacing, we also turn * off direct dispatch to also reduce memory pressure from I/Os * there, at the expxense of some added latency while the memory * pressures exist. See g_io_schedule_down() for more details * and limitations. */ static volatile u_int pace; static uma_zone_t biozone; /* * The head of the list of classifiers used in g_io_request. * Use g_register_classifier() and g_unregister_classifier() * to add/remove entries to the list. * Classifiers are invoked in registration order. */ static TAILQ_HEAD(g_classifier_tailq, g_classifier_hook) g_classifier_tailq = TAILQ_HEAD_INITIALIZER(g_classifier_tailq); #include static void g_bioq_lock(struct g_bioq *bq) { mtx_lock(&bq->bio_queue_lock); } static void g_bioq_unlock(struct g_bioq *bq) { mtx_unlock(&bq->bio_queue_lock); } #if 0 static void g_bioq_destroy(struct g_bioq *bq) { mtx_destroy(&bq->bio_queue_lock); } #endif static void g_bioq_init(struct g_bioq *bq) { TAILQ_INIT(&bq->bio_queue); mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); } static struct bio * g_bioq_first(struct g_bioq *bq) { struct bio *bp; bp = TAILQ_FIRST(&bq->bio_queue); if (bp != NULL) { KASSERT((bp->bio_flags & BIO_ONQUEUE), ("Bio not on queue bp=%p target %p", bp, bq)); bp->bio_flags &= ~BIO_ONQUEUE; TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); bq->bio_queue_length--; } return (bp); } struct bio * g_new_bio(void) { struct bio *bp; bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); #ifdef KTR if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { struct stack st; CTR1(KTR_GEOM, "g_new_bio(): %p", bp); stack_save(&st); CTRSTACK(KTR_GEOM, &st, 3, 0); } #endif return (bp); } struct bio * g_alloc_bio(void) { struct bio *bp; bp = uma_zalloc(biozone, M_WAITOK | M_ZERO); #ifdef KTR if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { struct stack st; CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp); stack_save(&st); CTRSTACK(KTR_GEOM, &st, 3, 0); } #endif return (bp); } void g_destroy_bio(struct bio *bp) { #ifdef KTR if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { struct stack st; CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp); stack_save(&st); CTRSTACK(KTR_GEOM, &st, 3, 0); } #endif uma_zfree(biozone, bp); } struct bio * g_clone_bio(struct bio *bp) { struct bio *bp2; bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); if (bp2 != NULL) { bp2->bio_parent = bp; bp2->bio_cmd = bp->bio_cmd; /* * BIO_ORDERED flag may be used by disk drivers to enforce * ordering restrictions, so this flag needs to be cloned. * BIO_UNMAPPED and BIO_VLIST should be inherited, to properly * indicate which way the buffer is passed. * Other bio flags are not suitable for cloning. */ bp2->bio_flags = bp->bio_flags & (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST); bp2->bio_length = bp->bio_length; bp2->bio_offset = bp->bio_offset; bp2->bio_data = bp->bio_data; bp2->bio_ma = bp->bio_ma; bp2->bio_ma_n = bp->bio_ma_n; bp2->bio_ma_offset = bp->bio_ma_offset; bp2->bio_attribute = bp->bio_attribute; /* Inherit classification info from the parent */ bp2->bio_classifier1 = bp->bio_classifier1; bp2->bio_classifier2 = bp->bio_classifier2; bp->bio_children++; } #ifdef KTR if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { struct stack st; CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2); stack_save(&st); CTRSTACK(KTR_GEOM, &st, 3, 0); } #endif return(bp2); } struct bio * g_duplicate_bio(struct bio *bp) { struct bio *bp2; bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO); bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST); bp2->bio_parent = bp; bp2->bio_cmd = bp->bio_cmd; bp2->bio_length = bp->bio_length; bp2->bio_offset = bp->bio_offset; bp2->bio_data = bp->bio_data; bp2->bio_ma = bp->bio_ma; bp2->bio_ma_n = bp->bio_ma_n; bp2->bio_ma_offset = bp->bio_ma_offset; bp2->bio_attribute = bp->bio_attribute; bp->bio_children++; #ifdef KTR if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { struct stack st; CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2); stack_save(&st); CTRSTACK(KTR_GEOM, &st, 3, 0); } #endif return(bp2); } void g_reset_bio(struct bio *bp) { bzero(bp, sizeof(*bp)); } void g_io_init() { g_bioq_init(&g_bio_run_down); g_bioq_init(&g_bio_run_up); g_bioq_init(&g_bio_run_task); biozone = uma_zcreate("g_bio", sizeof (struct bio), NULL, NULL, NULL, NULL, 0, 0); } int g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) { struct bio *bp; int error; g_trace(G_T_BIO, "bio_getattr(%s)", attr); bp = g_alloc_bio(); bp->bio_cmd = BIO_GETATTR; bp->bio_done = NULL; bp->bio_attribute = attr; bp->bio_length = *len; bp->bio_data = ptr; g_io_request(bp, cp); error = biowait(bp, "ggetattr"); *len = bp->bio_completed; g_destroy_bio(bp); return (error); } int g_io_flush(struct g_consumer *cp) { struct bio *bp; int error; g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name); bp = g_alloc_bio(); bp->bio_cmd = BIO_FLUSH; bp->bio_flags |= BIO_ORDERED; bp->bio_done = NULL; bp->bio_attribute = NULL; bp->bio_offset = cp->provider->mediasize; bp->bio_length = 0; bp->bio_data = NULL; g_io_request(bp, cp); error = biowait(bp, "gflush"); g_destroy_bio(bp); return (error); } static int g_io_check(struct bio *bp) { struct g_consumer *cp; struct g_provider *pp; off_t excess; int error; cp = bp->bio_from; pp = bp->bio_to; /* Fail if access counters dont allow the operation */ switch(bp->bio_cmd) { case BIO_READ: case BIO_GETATTR: if (cp->acr == 0) return (EPERM); break; case BIO_WRITE: case BIO_DELETE: case BIO_FLUSH: if (cp->acw == 0) return (EPERM); break; default: return (EPERM); } /* if provider is marked for error, don't disturb. */ if (pp->error) return (pp->error); if (cp->flags & G_CF_ORPHAN) return (ENXIO); switch(bp->bio_cmd) { case BIO_READ: case BIO_WRITE: case BIO_DELETE: /* Zero sectorsize or mediasize is probably a lack of media. */ if (pp->sectorsize == 0 || pp->mediasize == 0) return (ENXIO); /* Reject I/O not on sector boundary */ if (bp->bio_offset % pp->sectorsize) return (EINVAL); /* Reject I/O not integral sector long */ if (bp->bio_length % pp->sectorsize) return (EINVAL); /* Reject requests before or past the end of media. */ if (bp->bio_offset < 0) return (EIO); if (bp->bio_offset > pp->mediasize) return (EIO); /* Truncate requests to the end of providers media. */ excess = bp->bio_offset + bp->bio_length; if (excess > bp->bio_to->mediasize) { KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 || round_page(bp->bio_ma_offset + bp->bio_length) / PAGE_SIZE == bp->bio_ma_n, ("excess bio %p too short", bp)); excess -= bp->bio_to->mediasize; bp->bio_length -= excess; if ((bp->bio_flags & BIO_UNMAPPED) != 0) { bp->bio_ma_n = round_page(bp->bio_ma_offset + bp->bio_length) / PAGE_SIZE; } if (excess > 0) CTR3(KTR_GEOM, "g_down truncated bio " "%p provider %s by %d", bp, bp->bio_to->name, excess); } /* Deliver zero length transfers right here. */ if (bp->bio_length == 0) { CTR2(KTR_GEOM, "g_down terminated 0-length " "bp %p provider %s", bp, bp->bio_to->name); return (0); } if ((bp->bio_flags & BIO_UNMAPPED) != 0 && (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 && (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) { if ((error = g_io_transient_map_bio(bp)) >= 0) return (error); } break; default: break; } return (EJUSTRETURN); } /* * bio classification support. * * g_register_classifier() and g_unregister_classifier() * are used to add/remove a classifier from the list. * The list is protected using the g_bio_run_down lock, * because the classifiers are called in this path. * * g_io_request() passes bio's that are not already classified * (i.e. those with bio_classifier1 == NULL) to g_run_classifiers(). * Classifiers can store their result in the two fields * bio_classifier1 and bio_classifier2. * A classifier that updates one of the fields should * return a non-zero value. * If no classifier updates the field, g_run_classifiers() sets * bio_classifier1 = BIO_NOTCLASSIFIED to avoid further calls. */ int g_register_classifier(struct g_classifier_hook *hook) { g_bioq_lock(&g_bio_run_down); TAILQ_INSERT_TAIL(&g_classifier_tailq, hook, link); g_bioq_unlock(&g_bio_run_down); return (0); } void g_unregister_classifier(struct g_classifier_hook *hook) { struct g_classifier_hook *entry; g_bioq_lock(&g_bio_run_down); TAILQ_FOREACH(entry, &g_classifier_tailq, link) { if (entry == hook) { TAILQ_REMOVE(&g_classifier_tailq, hook, link); break; } } g_bioq_unlock(&g_bio_run_down); } static void g_run_classifiers(struct bio *bp) { struct g_classifier_hook *hook; int classified = 0; TAILQ_FOREACH(hook, &g_classifier_tailq, link) classified |= hook->func(hook->arg, bp); if (!classified) bp->bio_classifier1 = BIO_NOTCLASSIFIED; } void g_io_request(struct bio *bp, struct g_consumer *cp) { struct g_provider *pp; struct mtx *mtxp; int direct, error, first; uint8_t cmd; KASSERT(cp != NULL, ("NULL cp in g_io_request")); KASSERT(bp != NULL, ("NULL bp in g_io_request")); pp = cp->provider; KASSERT(pp != NULL, ("consumer not attached in g_io_request")); #ifdef DIAGNOSTIC KASSERT(bp->bio_driver1 == NULL, ("bio_driver1 used by the consumer (geom %s)", cp->geom->name)); KASSERT(bp->bio_driver2 == NULL, ("bio_driver2 used by the consumer (geom %s)", cp->geom->name)); KASSERT(bp->bio_pflags == 0, ("bio_pflags used by the consumer (geom %s)", cp->geom->name)); /* * Remember consumer's private fields, so we can detect if they were * modified by the provider. */ bp->_bio_caller1 = bp->bio_caller1; bp->_bio_caller2 = bp->bio_caller2; bp->_bio_cflags = bp->bio_cflags; #endif cmd = bp->bio_cmd; if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) { KASSERT(bp->bio_data != NULL, ("NULL bp->data in g_io_request(cmd=%hhu)", bp->bio_cmd)); } if (cmd == BIO_DELETE || cmd == BIO_FLUSH) { KASSERT(bp->bio_data == NULL, ("non-NULL bp->data in g_io_request(cmd=%hhu)", bp->bio_cmd)); } if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) { KASSERT(bp->bio_offset % cp->provider->sectorsize == 0, ("wrong offset %jd for sectorsize %u", bp->bio_offset, cp->provider->sectorsize)); KASSERT(bp->bio_length % cp->provider->sectorsize == 0, ("wrong length %jd for sectorsize %u", bp->bio_length, cp->provider->sectorsize)); } g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); bp->bio_from = cp; bp->bio_to = pp; bp->bio_error = 0; bp->bio_completed = 0; KASSERT(!(bp->bio_flags & BIO_ONQUEUE), ("Bio already on queue bp=%p", bp)); if ((g_collectstats & G_STATS_CONSUMERS) != 0 || ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) binuptime(&bp->bio_t0); else getbinuptime(&bp->bio_t0); #ifdef GET_STACK_USAGE direct = (cp->flags & G_CF_DIRECT_SEND) != 0 && (pp->flags & G_PF_DIRECT_RECEIVE) != 0 && !g_is_geom_thread(curthread) && ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 || (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) && pace == 0; if (direct) { /* Block direct execution if less then half of stack left. */ size_t st, su; GET_STACK_USAGE(st, su); if (su * 2 > st) direct = 0; } #else direct = 0; #endif if (!TAILQ_EMPTY(&g_classifier_tailq) && !bp->bio_classifier1) { g_bioq_lock(&g_bio_run_down); g_run_classifiers(bp); g_bioq_unlock(&g_bio_run_down); } /* * The statistics collection is lockless, as such, but we * can not update one instance of the statistics from more * than one thread at a time, so grab the lock first. */ mtxp = mtx_pool_find(mtxpool_sleep, pp); mtx_lock(mtxp); if (g_collectstats & G_STATS_PROVIDERS) devstat_start_transaction(pp->stat, &bp->bio_t0); if (g_collectstats & G_STATS_CONSUMERS) devstat_start_transaction(cp->stat, &bp->bio_t0); pp->nstart++; cp->nstart++; mtx_unlock(mtxp); if (direct) { error = g_io_check(bp); if (error >= 0) { CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p " "provider %s returned %d", bp, bp->bio_to->name, error); g_io_deliver(bp, error); return; } bp->bio_to->geom->start(bp); } else { g_bioq_lock(&g_bio_run_down); first = TAILQ_EMPTY(&g_bio_run_down.bio_queue); TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue); bp->bio_flags |= BIO_ONQUEUE; g_bio_run_down.bio_queue_length++; g_bioq_unlock(&g_bio_run_down); /* Pass it on down. */ if (first) wakeup(&g_wait_down); } } void g_io_deliver(struct bio *bp, int error) { struct bintime now; struct g_consumer *cp; struct g_provider *pp; struct mtx *mtxp; int direct, first; KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); pp = bp->bio_to; KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); cp = bp->bio_from; if (cp == NULL) { bp->bio_error = error; bp->bio_done(bp); return; } KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); #ifdef DIAGNOSTIC /* * Some classes - GJournal in particular - can modify bio's * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO * flag means it's an expected behaviour for that particular geom. */ if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) { KASSERT(bp->bio_caller1 == bp->_bio_caller1, ("bio_caller1 used by the provider %s", pp->name)); KASSERT(bp->bio_caller2 == bp->_bio_caller2, ("bio_caller2 used by the provider %s", pp->name)); KASSERT(bp->bio_cflags == bp->_bio_cflags, ("bio_cflags used by the provider %s", pp->name)); } #endif KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); KASSERT(bp->bio_completed <= bp->bio_length, ("bio_completed can't be greater than bio_length")); g_trace(G_T_BIO, "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); KASSERT(!(bp->bio_flags & BIO_ONQUEUE), ("Bio already on queue bp=%p", bp)); /* * XXX: next two doesn't belong here */ bp->bio_bcount = bp->bio_length; bp->bio_resid = bp->bio_bcount - bp->bio_completed; #ifdef GET_STACK_USAGE direct = (pp->flags & G_PF_DIRECT_SEND) && (cp->flags & G_CF_DIRECT_RECEIVE) && !g_is_geom_thread(curthread); if (direct) { /* Block direct execution if less then half of stack left. */ size_t st, su; GET_STACK_USAGE(st, su); if (su * 2 > st) direct = 0; } #else direct = 0; #endif /* * The statistics collection is lockless, as such, but we * can not update one instance of the statistics from more * than one thread at a time, so grab the lock first. */ if ((g_collectstats & G_STATS_CONSUMERS) != 0 || ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) binuptime(&now); mtxp = mtx_pool_find(mtxpool_sleep, cp); mtx_lock(mtxp); if (g_collectstats & G_STATS_PROVIDERS) devstat_end_transaction_bio_bt(pp->stat, bp, &now); if (g_collectstats & G_STATS_CONSUMERS) devstat_end_transaction_bio_bt(cp->stat, bp, &now); cp->nend++; pp->nend++; mtx_unlock(mtxp); if (error != ENOMEM) { bp->bio_error = error; if (direct) { biodone(bp); } else { g_bioq_lock(&g_bio_run_up); first = TAILQ_EMPTY(&g_bio_run_up.bio_queue); TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue); bp->bio_flags |= BIO_ONQUEUE; g_bio_run_up.bio_queue_length++; g_bioq_unlock(&g_bio_run_up); if (first) wakeup(&g_wait_up); } return; } if (bootverbose) printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); bp->bio_children = 0; bp->bio_inbed = 0; bp->bio_driver1 = NULL; bp->bio_driver2 = NULL; bp->bio_pflags = 0; g_io_request(bp, cp); pace = 1; return; } SYSCTL_DECL(_kern_geom); static long transient_maps; SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD, &transient_maps, 0, "Total count of the transient mapping requests"); u_int transient_map_retries = 10; SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW, &transient_map_retries, 0, "Max count of retries used before giving up on creating transient map"); int transient_map_hard_failures; SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD, &transient_map_hard_failures, 0, "Failures to establish the transient mapping due to retry attempts " "exhausted"); int transient_map_soft_failures; SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD, &transient_map_soft_failures, 0, "Count of retried failures to establish the transient mapping"); int inflight_transient_maps; SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD, &inflight_transient_maps, 0, "Current count of the active transient maps"); static int g_io_transient_map_bio(struct bio *bp) { vm_offset_t addr; long size; u_int retried; KASSERT(unmapped_buf_allowed, ("unmapped disabled")); size = round_page(bp->bio_ma_offset + bp->bio_length); KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp)); addr = 0; retried = 0; atomic_add_long(&transient_maps, 1); retry: if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) { if (transient_map_retries != 0 && retried >= transient_map_retries) { CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s", bp, bp->bio_to->name); atomic_add_int(&transient_map_hard_failures, 1); return (EDEADLK/* XXXKIB */); } else { /* * Naive attempt to quisce the I/O to get more * in-flight requests completed and defragment * the transient_arena. */ CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d", bp, bp->bio_to->name, retried); pause("g_d_tra", hz / 10); retried++; atomic_add_int(&transient_map_soft_failures, 1); goto retry; } } atomic_add_int(&inflight_transient_maps, 1); pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size)); bp->bio_data = (caddr_t)addr + bp->bio_ma_offset; bp->bio_flags |= BIO_TRANSIENT_MAPPING; bp->bio_flags &= ~BIO_UNMAPPED; return (EJUSTRETURN); } void g_io_schedule_down(struct thread *tp __unused) { struct bio *bp; int error; for(;;) { g_bioq_lock(&g_bio_run_down); bp = g_bioq_first(&g_bio_run_down); if (bp == NULL) { CTR0(KTR_GEOM, "g_down going to sleep"); msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, PRIBIO | PDROP, "-", 0); continue; } CTR0(KTR_GEOM, "g_down has work to do"); g_bioq_unlock(&g_bio_run_down); if (pace != 0) { /* * There has been at least one memory allocation * failure since the last I/O completed. Pause 1ms to * give the system a chance to free up memory. We only * do this once because a large number of allocations * can fail in the direct dispatch case and there's no * relationship between the number of these failures and * the length of the outage. If there's still an outage, * we'll pause again and again until it's * resolved. Older versions paused longer and once per * allocation failure. This was OK for a single threaded * g_down, but with direct dispatch would lead to max of * 10 IOPs for minutes at a time when transient memory * issues prevented allocation for a batch of requests * from the upper layers. * * XXX This pacing is really lame. It needs to be solved * by other methods. This is OK only because the worst * case scenario is so rare. In the worst case scenario * all memory is tied up waiting for I/O to complete * which can never happen since we can't allocate bios * for that I/O. */ CTR0(KTR_GEOM, "g_down pacing self"); pause("g_down", min(hz/1000, 1)); pace = 0; } CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp, bp->bio_to->name); error = g_io_check(bp); if (error >= 0) { CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider " "%s returned %d", bp, bp->bio_to->name, error); g_io_deliver(bp, error); continue; } THREAD_NO_SLEEPING(); CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld " "len %ld", bp, bp->bio_to->name, bp->bio_offset, bp->bio_length); bp->bio_to->geom->start(bp); THREAD_SLEEPING_OK(); } } void bio_taskqueue(struct bio *bp, bio_task_t *func, void *arg) { bp->bio_task = func; bp->bio_task_arg = arg; /* * The taskqueue is actually just a second queue off the "up" * queue, so we use the same lock. */ g_bioq_lock(&g_bio_run_up); KASSERT(!(bp->bio_flags & BIO_ONQUEUE), ("Bio already on queue bp=%p target taskq", bp)); bp->bio_flags |= BIO_ONQUEUE; TAILQ_INSERT_TAIL(&g_bio_run_task.bio_queue, bp, bio_queue); g_bio_run_task.bio_queue_length++; wakeup(&g_wait_up); g_bioq_unlock(&g_bio_run_up); } void g_io_schedule_up(struct thread *tp __unused) { struct bio *bp; for(;;) { g_bioq_lock(&g_bio_run_up); bp = g_bioq_first(&g_bio_run_task); if (bp != NULL) { g_bioq_unlock(&g_bio_run_up); THREAD_NO_SLEEPING(); CTR1(KTR_GEOM, "g_up processing task bp %p", bp); bp->bio_task(bp->bio_task_arg); THREAD_SLEEPING_OK(); continue; } bp = g_bioq_first(&g_bio_run_up); if (bp != NULL) { g_bioq_unlock(&g_bio_run_up); THREAD_NO_SLEEPING(); CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off " "%jd len %ld", bp, bp->bio_to->name, bp->bio_offset, bp->bio_length); biodone(bp); THREAD_SLEEPING_OK(); continue; } CTR0(KTR_GEOM, "g_up going to sleep"); msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, PRIBIO | PDROP, "-", 0); } } void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) { struct bio *bp; void *ptr; int errorc; KASSERT(length > 0 && length >= cp->provider->sectorsize && length <= MAXPHYS, ("g_read_data(): invalid length %jd", (intmax_t)length)); bp = g_alloc_bio(); bp->bio_cmd = BIO_READ; bp->bio_done = NULL; bp->bio_offset = offset; bp->bio_length = length; ptr = g_malloc(length, M_WAITOK); bp->bio_data = ptr; g_io_request(bp, cp); errorc = biowait(bp, "gread"); if (error != NULL) *error = errorc; g_destroy_bio(bp); if (errorc) { g_free(ptr); ptr = NULL; } return (ptr); } int g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) { struct bio *bp; int error; KASSERT(length > 0 && length >= cp->provider->sectorsize && length <= MAXPHYS, ("g_write_data(): invalid length %jd", (intmax_t)length)); bp = g_alloc_bio(); bp->bio_cmd = BIO_WRITE; bp->bio_done = NULL; bp->bio_offset = offset; bp->bio_length = length; bp->bio_data = ptr; g_io_request(bp, cp); error = biowait(bp, "gwrite"); g_destroy_bio(bp); return (error); } int g_delete_data(struct g_consumer *cp, off_t offset, off_t length) { struct bio *bp; int error; KASSERT(length > 0 && length >= cp->provider->sectorsize, ("g_delete_data(): invalid length %jd", (intmax_t)length)); bp = g_alloc_bio(); bp->bio_cmd = BIO_DELETE; bp->bio_done = NULL; bp->bio_offset = offset; bp->bio_length = length; bp->bio_data = NULL; g_io_request(bp, cp); error = biowait(bp, "gdelete"); g_destroy_bio(bp); return (error); } void g_print_bio(struct bio *bp) { const char *pname, *cmd = NULL; if (bp->bio_to != NULL) pname = bp->bio_to->name; else pname = "[unknown]"; switch (bp->bio_cmd) { case BIO_GETATTR: cmd = "GETATTR"; printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute); return; case BIO_FLUSH: cmd = "FLUSH"; printf("%s[%s]", pname, cmd); return; case BIO_READ: cmd = "READ"; break; case BIO_WRITE: cmd = "WRITE"; break; case BIO_DELETE: cmd = "DELETE"; break; default: cmd = "UNKNOWN"; printf("%s[%s()]", pname, cmd); return; } printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd, (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); }