/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or https://opensource.org/licenses/CDDL-1.0. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2012, 2015 by Delphix. All rights reserved. * Copyright (c) 2017, Intel Corporation. * Copyright (c) 2024, Klara Inc. */ /* * ZFS fault injection * * To handle fault injection, we keep track of a series of zinject_record_t * structures which describe which logical block(s) should be injected with a * fault. These are kept in a global list. Each record corresponds to a given * spa_t and maintains a special hold on the spa_t so that it cannot be deleted * or exported while the injection record exists. * * Device level injection is done using the 'zi_guid' field. If this is set, it * means that the error is destined for a particular device, not a piece of * data. * * This is a rather poor data structure and algorithm, but we don't expect more * than a few faults at any one time, so it should be sufficient for our needs. */ #include #include #include #include #include #include #include uint32_t zio_injection_enabled = 0; /* * Data describing each zinject handler registered on the system, and * contains the list node linking the handler in the global zinject * handler list. */ typedef struct inject_handler { int zi_id; spa_t *zi_spa; char *zi_spa_name; /* ZINJECT_DELAY_IMPORT only */ zinject_record_t zi_record; uint64_t *zi_lanes; int zi_next_lane; list_node_t zi_link; } inject_handler_t; /* * List of all zinject handlers registered on the system, protected by * the inject_lock defined below. */ static list_t inject_handlers; /* * This protects insertion into, and traversal of, the inject handler * list defined above; as well as the inject_delay_count. Any time a * handler is inserted or removed from the list, this lock should be * taken as a RW_WRITER; and any time traversal is done over the list * (without modification to it) this lock should be taken as a RW_READER. */ static krwlock_t inject_lock; /* * This holds the number of zinject delay handlers that have been * registered on the system. It is protected by the inject_lock defined * above. Thus modifications to this count must be a RW_WRITER of the * inject_lock, and reads of this count must be (at least) a RW_READER * of the lock. */ static int inject_delay_count = 0; /* * This lock is used only in zio_handle_io_delay(), refer to the comment * in that function for more details. */ static kmutex_t inject_delay_mtx; /* * Used to assign unique identifying numbers to each new zinject handler. */ static int inject_next_id = 1; /* * Test if the requested frequency was triggered */ static boolean_t freq_triggered(uint32_t frequency) { /* * zero implies always (100%) */ if (frequency == 0) return (B_TRUE); /* * Note: we still handle legacy (unscaled) frequency values */ uint32_t maximum = (frequency <= 100) ? 100 : ZI_PERCENTAGE_MAX; return (random_in_range(maximum) < frequency); } /* * Returns true if the given record matches the I/O in progress. */ static boolean_t zio_match_handler(const zbookmark_phys_t *zb, uint64_t type, int dva, zinject_record_t *record, int error) { /* * Check for a match against the MOS, which is based on type */ if (zb->zb_objset == DMU_META_OBJSET && record->zi_objset == DMU_META_OBJSET && record->zi_object == DMU_META_DNODE_OBJECT) { if (record->zi_type == DMU_OT_NONE || type == record->zi_type) return (freq_triggered(record->zi_freq)); else return (B_FALSE); } /* * Check for an exact match. */ if (zb->zb_objset == record->zi_objset && zb->zb_object == record->zi_object && zb->zb_level == record->zi_level && zb->zb_blkid >= record->zi_start && zb->zb_blkid <= record->zi_end && (record->zi_dvas == 0 || (dva != ZI_NO_DVA && (record->zi_dvas & (1ULL << dva)))) && error == record->zi_error) { return (freq_triggered(record->zi_freq)); } return (B_FALSE); } /* * Panic the system when a config change happens in the function * specified by tag. */ void zio_handle_panic_injection(spa_t *spa, const char *tag, uint64_t type) { inject_handler_t *handler; rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { if (spa != handler->zi_spa) continue; if (handler->zi_record.zi_type == type && strcmp(tag, handler->zi_record.zi_func) == 0) panic("Panic requested in function %s\n", tag); } rw_exit(&inject_lock); } /* * Inject a decryption failure. Decryption failures can occur in * both the ARC and the ZIO layers. */ int zio_handle_decrypt_injection(spa_t *spa, const zbookmark_phys_t *zb, uint64_t type, int error) { int ret = 0; inject_handler_t *handler; rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { if (spa != handler->zi_spa || handler->zi_record.zi_cmd != ZINJECT_DECRYPT_FAULT) continue; if (zio_match_handler(zb, type, ZI_NO_DVA, &handler->zi_record, error)) { ret = error; break; } } rw_exit(&inject_lock); return (ret); } /* * If this is a physical I/O for a vdev child determine which DVA it is * for. We iterate backwards through the DVAs matching on the offset so * that we end up with ZI_NO_DVA (-1) if we don't find a match. */ static int zio_match_dva(zio_t *zio) { int i = ZI_NO_DVA; if (zio->io_bp != NULL && zio->io_vd != NULL && zio->io_child_type == ZIO_CHILD_VDEV) { for (i = BP_GET_NDVAS(zio->io_bp) - 1; i >= 0; i--) { dva_t *dva = &zio->io_bp->blk_dva[i]; uint64_t off = DVA_GET_OFFSET(dva); vdev_t *vd = vdev_lookup_top(zio->io_spa, DVA_GET_VDEV(dva)); /* Compensate for vdev label added to leaves */ if (zio->io_vd->vdev_ops->vdev_op_leaf) off += VDEV_LABEL_START_SIZE; if (zio->io_vd == vd && zio->io_offset == off) break; } } return (i); } /* * Determine if the I/O in question should return failure. Returns the errno * to be returned to the caller. */ int zio_handle_fault_injection(zio_t *zio, int error) { int ret = 0; inject_handler_t *handler; /* * Ignore I/O not associated with any logical data. */ if (zio->io_logical == NULL) return (0); /* * Currently, we only support fault injection on reads. */ if (zio->io_type != ZIO_TYPE_READ) return (0); /* * A rebuild I/O has no checksum to verify. */ if (zio->io_priority == ZIO_PRIORITY_REBUILD && error == ECKSUM) return (0); rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { if (zio->io_spa != handler->zi_spa || handler->zi_record.zi_cmd != ZINJECT_DATA_FAULT) continue; /* If this handler matches, return the specified error */ if (zio_match_handler(&zio->io_logical->io_bookmark, zio->io_bp ? BP_GET_TYPE(zio->io_bp) : DMU_OT_NONE, zio_match_dva(zio), &handler->zi_record, error)) { ret = error; break; } } rw_exit(&inject_lock); return (ret); } /* * Determine if the zio is part of a label update and has an injection * handler associated with that portion of the label. Currently, we * allow error injection in either the nvlist or the uberblock region of * of the vdev label. */ int zio_handle_label_injection(zio_t *zio, int error) { inject_handler_t *handler; vdev_t *vd = zio->io_vd; uint64_t offset = zio->io_offset; int label; int ret = 0; if (offset >= VDEV_LABEL_START_SIZE && offset < vd->vdev_psize - VDEV_LABEL_END_SIZE) return (0); rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { uint64_t start = handler->zi_record.zi_start; uint64_t end = handler->zi_record.zi_end; if (handler->zi_record.zi_cmd != ZINJECT_LABEL_FAULT) continue; /* * The injection region is the relative offsets within a * vdev label. We must determine the label which is being * updated and adjust our region accordingly. */ label = vdev_label_number(vd->vdev_psize, offset); start = vdev_label_offset(vd->vdev_psize, label, start); end = vdev_label_offset(vd->vdev_psize, label, end); if (zio->io_vd->vdev_guid == handler->zi_record.zi_guid && (offset >= start && offset <= end)) { ret = error; break; } } rw_exit(&inject_lock); return (ret); } static int zio_inject_bitflip_cb(void *data, size_t len, void *private) { zio_t *zio = private; uint8_t *buffer = data; uint_t byte = random_in_range(len); ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); /* flip a single random bit in an abd data buffer */ buffer[byte] ^= 1 << random_in_range(8); return (1); /* stop after first flip */ } static int zio_handle_device_injection_impl(vdev_t *vd, zio_t *zio, int err1, int err2) { inject_handler_t *handler; int ret = 0; /* * We skip over faults in the labels unless it's during device open * (i.e. zio == NULL) or a device flush (offset is meaningless) */ if (zio != NULL && zio->io_type != ZIO_TYPE_FLUSH) { uint64_t offset = zio->io_offset; if (offset < VDEV_LABEL_START_SIZE || offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE) return (0); } rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { if (handler->zi_record.zi_cmd != ZINJECT_DEVICE_FAULT) continue; if (vd->vdev_guid == handler->zi_record.zi_guid) { if (handler->zi_record.zi_failfast && (zio == NULL || (zio->io_flags & (ZIO_FLAG_IO_RETRY | ZIO_FLAG_TRYHARD)))) { continue; } /* Handle type specific I/O failures */ if (zio != NULL && handler->zi_record.zi_iotype != ZIO_TYPES && handler->zi_record.zi_iotype != zio->io_type) continue; if (handler->zi_record.zi_error == err1 || handler->zi_record.zi_error == err2) { /* * limit error injection if requested */ if (!freq_triggered(handler->zi_record.zi_freq)) continue; /* * For a failed open, pretend like the device * has gone away. */ if (err1 == ENXIO) vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; /* * Treat these errors as if they had been * retried so that all the appropriate stats * and FMA events are generated. */ if (!handler->zi_record.zi_failfast && zio != NULL) zio->io_flags |= ZIO_FLAG_IO_RETRY; /* * EILSEQ means flip a bit after a read */ if (handler->zi_record.zi_error == EILSEQ) { if (zio == NULL) break; /* locate buffer data and flip a bit */ (void) abd_iterate_func(zio->io_abd, 0, zio->io_size, zio_inject_bitflip_cb, zio); break; } ret = handler->zi_record.zi_error; break; } if (handler->zi_record.zi_error == ENXIO) { ret = SET_ERROR(EIO); break; } } } rw_exit(&inject_lock); return (ret); } int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error) { return (zio_handle_device_injection_impl(vd, zio, error, INT_MAX)); } int zio_handle_device_injections(vdev_t *vd, zio_t *zio, int err1, int err2) { return (zio_handle_device_injection_impl(vd, zio, err1, err2)); } /* * Simulate hardware that ignores cache flushes. For requested number * of seconds nix the actual writing to disk. */ void zio_handle_ignored_writes(zio_t *zio) { inject_handler_t *handler; rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { /* Ignore errors not destined for this pool */ if (zio->io_spa != handler->zi_spa || handler->zi_record.zi_cmd != ZINJECT_IGNORED_WRITES) continue; /* * Positive duration implies # of seconds, negative * a number of txgs */ if (handler->zi_record.zi_timer == 0) { if (handler->zi_record.zi_duration > 0) handler->zi_record.zi_timer = ddi_get_lbolt64(); else handler->zi_record.zi_timer = zio->io_txg; } /* Have a "problem" writing 60% of the time */ if (random_in_range(100) < 60) zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES; break; } rw_exit(&inject_lock); } void spa_handle_ignored_writes(spa_t *spa) { inject_handler_t *handler; if (zio_injection_enabled == 0) return; rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { if (spa != handler->zi_spa || handler->zi_record.zi_cmd != ZINJECT_IGNORED_WRITES) continue; if (handler->zi_record.zi_duration > 0) { VERIFY(handler->zi_record.zi_timer == 0 || ddi_time_after64( (int64_t)handler->zi_record.zi_timer + handler->zi_record.zi_duration * hz, ddi_get_lbolt64())); } else { /* duration is negative so the subtraction here adds */ VERIFY(handler->zi_record.zi_timer == 0 || handler->zi_record.zi_timer - handler->zi_record.zi_duration >= spa_syncing_txg(spa)); } } rw_exit(&inject_lock); } hrtime_t zio_handle_io_delay(zio_t *zio) { vdev_t *vd = zio->io_vd; inject_handler_t *min_handler = NULL; hrtime_t min_target = 0; rw_enter(&inject_lock, RW_READER); /* * inject_delay_count is a subset of zio_injection_enabled that * is only incremented for delay handlers. These checks are * mainly added to remind the reader why we're not explicitly * checking zio_injection_enabled like the other functions. */ IMPLY(inject_delay_count > 0, zio_injection_enabled > 0); IMPLY(zio_injection_enabled == 0, inject_delay_count == 0); /* * If there aren't any inject delay handlers registered, then we * can short circuit and simply return 0 here. A value of zero * informs zio_delay_interrupt() that this request should not be * delayed. This short circuit keeps us from acquiring the * inject_delay_mutex unnecessarily. */ if (inject_delay_count == 0) { rw_exit(&inject_lock); return (0); } /* * Each inject handler has a number of "lanes" associated with * it. Each lane is able to handle requests independently of one * another, and at a latency defined by the inject handler * record's zi_timer field. Thus if a handler in configured with * a single lane with a 10ms latency, it will delay requests * such that only a single request is completed every 10ms. So, * if more than one request is attempted per each 10ms interval, * the average latency of the requests will be greater than * 10ms; but if only a single request is submitted each 10ms * interval the average latency will be 10ms. * * We need to acquire this mutex to prevent multiple concurrent * threads being assigned to the same lane of a given inject * handler. The mutex allows us to perform the following two * operations atomically: * * 1. determine the minimum handler and minimum target * value of all the possible handlers * 2. update that minimum handler's lane array * * Without atomicity, two (or more) threads could pick the same * lane in step (1), and then conflict with each other in step * (2). This could allow a single lane handler to process * multiple requests simultaneously, which shouldn't be possible. */ mutex_enter(&inject_delay_mtx); for (inject_handler_t *handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { if (handler->zi_record.zi_cmd != ZINJECT_DELAY_IO) continue; if (!freq_triggered(handler->zi_record.zi_freq)) continue; if (vd->vdev_guid != handler->zi_record.zi_guid) continue; /* also match on I/O type (e.g., -T read) */ if (handler->zi_record.zi_iotype != ZIO_TYPES && handler->zi_record.zi_iotype != zio->io_type) { continue; } /* * Defensive; should never happen as the array allocation * occurs prior to inserting this handler on the list. */ ASSERT3P(handler->zi_lanes, !=, NULL); /* * This should never happen, the zinject command should * prevent a user from setting an IO delay with zero lanes. */ ASSERT3U(handler->zi_record.zi_nlanes, !=, 0); ASSERT3U(handler->zi_record.zi_nlanes, >, handler->zi_next_lane); /* * We want to issue this IO to the lane that will become * idle the soonest, so we compare the soonest this * specific handler can complete the IO with all other * handlers, to find the lowest value of all possible * lanes. We then use this lane to submit the request. * * Since each handler has a constant value for its * delay, we can just use the "next" lane for that * handler; as it will always be the lane with the * lowest value for that particular handler (i.e. the * lane that will become idle the soonest). This saves a * scan of each handler's lanes array. * * There's two cases to consider when determining when * this specific IO request should complete. If this * lane is idle, we want to "submit" the request now so * it will complete after zi_timer milliseconds. Thus, * we set the target to now + zi_timer. * * If the lane is busy, we want this request to complete * zi_timer milliseconds after the lane becomes idle. * Since the 'zi_lanes' array holds the time at which * each lane will become idle, we use that value to * determine when this request should complete. */ hrtime_t idle = handler->zi_record.zi_timer + gethrtime(); hrtime_t busy = handler->zi_record.zi_timer + handler->zi_lanes[handler->zi_next_lane]; hrtime_t target = MAX(idle, busy); if (min_handler == NULL) { min_handler = handler; min_target = target; continue; } ASSERT3P(min_handler, !=, NULL); ASSERT3U(min_target, !=, 0); /* * We don't yet increment the "next lane" variable since * we still might find a lower value lane in another * handler during any remaining iterations. Once we're * sure we've selected the absolute minimum, we'll claim * the lane and increment the handler's "next lane" * field below. */ if (target < min_target) { min_handler = handler; min_target = target; } } /* * 'min_handler' will be NULL if no IO delays are registered for * this vdev, otherwise it will point to the handler containing * the lane that will become idle the soonest. */ if (min_handler != NULL) { ASSERT3U(min_target, !=, 0); min_handler->zi_lanes[min_handler->zi_next_lane] = min_target; /* * If we've used all possible lanes for this handler, * loop back and start using the first lane again; * otherwise, just increment the lane index. */ min_handler->zi_next_lane = (min_handler->zi_next_lane + 1) % min_handler->zi_record.zi_nlanes; } mutex_exit(&inject_delay_mtx); rw_exit(&inject_lock); return (min_target); } static void zio_handle_pool_delay(spa_t *spa, hrtime_t elapsed, zinject_type_t command) { inject_handler_t *handler; hrtime_t delay = 0; int id = 0; rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL && handler->zi_record.zi_cmd == command; handler = list_next(&inject_handlers, handler)) { ASSERT3P(handler->zi_spa_name, !=, NULL); if (strcmp(spa_name(spa), handler->zi_spa_name) == 0) { uint64_t pause = SEC2NSEC(handler->zi_record.zi_duration); if (pause > elapsed) { delay = pause - elapsed; } id = handler->zi_id; break; } } rw_exit(&inject_lock); if (delay) { if (command == ZINJECT_DELAY_IMPORT) { spa_import_progress_set_notes(spa, "injecting %llu " "sec delay", (u_longlong_t)NSEC2SEC(delay)); } zfs_sleep_until(gethrtime() + delay); } if (id) { /* all done with this one-shot handler */ zio_clear_fault(id); } } /* * For testing, inject a delay during an import */ void zio_handle_import_delay(spa_t *spa, hrtime_t elapsed) { zio_handle_pool_delay(spa, elapsed, ZINJECT_DELAY_IMPORT); } /* * For testing, inject a delay during an export */ void zio_handle_export_delay(spa_t *spa, hrtime_t elapsed) { zio_handle_pool_delay(spa, elapsed, ZINJECT_DELAY_EXPORT); } static int zio_calculate_range(const char *pool, zinject_record_t *record) { dsl_pool_t *dp; dsl_dataset_t *ds; objset_t *os = NULL; dnode_t *dn = NULL; int error; /* * Obtain the dnode for object using pool, objset, and object */ error = dsl_pool_hold(pool, FTAG, &dp); if (error) return (error); error = dsl_dataset_hold_obj(dp, record->zi_objset, FTAG, &ds); dsl_pool_rele(dp, FTAG); if (error) return (error); error = dmu_objset_from_ds(ds, &os); dsl_dataset_rele(ds, FTAG); if (error) return (error); error = dnode_hold(os, record->zi_object, FTAG, &dn); if (error) return (error); /* * Translate the range into block IDs */ if (record->zi_start != 0 || record->zi_end != -1ULL) { record->zi_start >>= dn->dn_datablkshift; record->zi_end >>= dn->dn_datablkshift; } if (record->zi_level > 0) { if (record->zi_level >= dn->dn_nlevels) { dnode_rele(dn, FTAG); return (SET_ERROR(EDOM)); } if (record->zi_start != 0 || record->zi_end != 0) { int shift = dn->dn_indblkshift - SPA_BLKPTRSHIFT; for (int level = record->zi_level; level > 0; level--) { record->zi_start >>= shift; record->zi_end >>= shift; } } } dnode_rele(dn, FTAG); return (0); } static boolean_t zio_pool_handler_exists(const char *name, zinject_type_t command) { boolean_t exists = B_FALSE; rw_enter(&inject_lock, RW_READER); for (inject_handler_t *handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) { if (command != handler->zi_record.zi_cmd) continue; const char *pool = (handler->zi_spa_name != NULL) ? handler->zi_spa_name : spa_name(handler->zi_spa); if (strcmp(name, pool) == 0) { exists = B_TRUE; break; } } rw_exit(&inject_lock); return (exists); } /* * Create a new handler for the given record. We add it to the list, adding * a reference to the spa_t in the process. We increment zio_injection_enabled, * which is the switch to trigger all fault injection. */ int zio_inject_fault(char *name, int flags, int *id, zinject_record_t *record) { inject_handler_t *handler; int error; spa_t *spa; /* * If this is pool-wide metadata, make sure we unload the corresponding * spa_t, so that the next attempt to load it will trigger the fault. * We call spa_reset() to unload the pool appropriately. */ if (flags & ZINJECT_UNLOAD_SPA) if ((error = spa_reset(name)) != 0) return (error); if (record->zi_cmd == ZINJECT_DELAY_IO) { /* * A value of zero for the number of lanes or for the * delay time doesn't make sense. */ if (record->zi_timer == 0 || record->zi_nlanes == 0) return (SET_ERROR(EINVAL)); /* * The number of lanes is directly mapped to the size of * an array used by the handler. Thus, to ensure the * user doesn't trigger an allocation that's "too large" * we cap the number of lanes here. */ if (record->zi_nlanes >= UINT16_MAX) return (SET_ERROR(EINVAL)); } /* * If the supplied range was in bytes -- calculate the actual blkid */ if (flags & ZINJECT_CALC_RANGE) { error = zio_calculate_range(name, record); if (error != 0) return (error); } if (!(flags & ZINJECT_NULL)) { /* * Pool delays for import or export don't take an * injection reference on the spa. Instead they * rely on matching by name. */ if (record->zi_cmd == ZINJECT_DELAY_IMPORT || record->zi_cmd == ZINJECT_DELAY_EXPORT) { if (record->zi_duration <= 0) return (SET_ERROR(EINVAL)); /* * Only one import | export delay handler per pool. */ if (zio_pool_handler_exists(name, record->zi_cmd)) return (SET_ERROR(EEXIST)); mutex_enter(&spa_namespace_lock); boolean_t has_spa = spa_lookup(name) != NULL; mutex_exit(&spa_namespace_lock); if (record->zi_cmd == ZINJECT_DELAY_IMPORT && has_spa) return (SET_ERROR(EEXIST)); if (record->zi_cmd == ZINJECT_DELAY_EXPORT && !has_spa) return (SET_ERROR(ENOENT)); spa = NULL; } else { /* * spa_inject_ref() will add an injection reference, * which will prevent the pool from being removed * from the namespace while still allowing it to be * unloaded. */ if ((spa = spa_inject_addref(name)) == NULL) return (SET_ERROR(ENOENT)); } handler = kmem_alloc(sizeof (inject_handler_t), KM_SLEEP); handler->zi_spa = spa; /* note: can be NULL */ handler->zi_record = *record; if (handler->zi_record.zi_cmd == ZINJECT_DELAY_IO) { handler->zi_lanes = kmem_zalloc( sizeof (*handler->zi_lanes) * handler->zi_record.zi_nlanes, KM_SLEEP); handler->zi_next_lane = 0; } else { handler->zi_lanes = NULL; handler->zi_next_lane = 0; } if (handler->zi_spa == NULL) handler->zi_spa_name = spa_strdup(name); else handler->zi_spa_name = NULL; rw_enter(&inject_lock, RW_WRITER); /* * We can't move this increment into the conditional * above because we need to hold the RW_WRITER lock of * inject_lock, and we don't want to hold that while * allocating the handler's zi_lanes array. */ if (handler->zi_record.zi_cmd == ZINJECT_DELAY_IO) { ASSERT3S(inject_delay_count, >=, 0); inject_delay_count++; ASSERT3S(inject_delay_count, >, 0); } *id = handler->zi_id = inject_next_id++; list_insert_tail(&inject_handlers, handler); atomic_inc_32(&zio_injection_enabled); rw_exit(&inject_lock); } /* * Flush the ARC, so that any attempts to read this data will end up * going to the ZIO layer. Note that this is a little overkill, but * we don't have the necessary ARC interfaces to do anything else, and * fault injection isn't a performance critical path. */ if (flags & ZINJECT_FLUSH_ARC) /* * We must use FALSE to ensure arc_flush returns, since * we're not preventing concurrent ARC insertions. */ arc_flush(NULL, FALSE); return (0); } /* * Returns the next record with an ID greater than that supplied to the * function. Used to iterate over all handlers in the system. */ int zio_inject_list_next(int *id, char *name, size_t buflen, zinject_record_t *record) { inject_handler_t *handler; int ret; mutex_enter(&spa_namespace_lock); rw_enter(&inject_lock, RW_READER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) if (handler->zi_id > *id) break; if (handler) { *record = handler->zi_record; *id = handler->zi_id; ASSERT(handler->zi_spa || handler->zi_spa_name); if (handler->zi_spa != NULL) (void) strlcpy(name, spa_name(handler->zi_spa), buflen); else (void) strlcpy(name, handler->zi_spa_name, buflen); ret = 0; } else { ret = SET_ERROR(ENOENT); } rw_exit(&inject_lock); mutex_exit(&spa_namespace_lock); return (ret); } /* * Clear the fault handler with the given identifier, or return ENOENT if none * exists. */ int zio_clear_fault(int id) { inject_handler_t *handler; rw_enter(&inject_lock, RW_WRITER); for (handler = list_head(&inject_handlers); handler != NULL; handler = list_next(&inject_handlers, handler)) if (handler->zi_id == id) break; if (handler == NULL) { rw_exit(&inject_lock); return (SET_ERROR(ENOENT)); } if (handler->zi_record.zi_cmd == ZINJECT_DELAY_IO) { ASSERT3S(inject_delay_count, >, 0); inject_delay_count--; ASSERT3S(inject_delay_count, >=, 0); } list_remove(&inject_handlers, handler); rw_exit(&inject_lock); if (handler->zi_record.zi_cmd == ZINJECT_DELAY_IO) { ASSERT3P(handler->zi_lanes, !=, NULL); kmem_free(handler->zi_lanes, sizeof (*handler->zi_lanes) * handler->zi_record.zi_nlanes); } else { ASSERT3P(handler->zi_lanes, ==, NULL); } if (handler->zi_spa_name != NULL) spa_strfree(handler->zi_spa_name); if (handler->zi_spa != NULL) spa_inject_delref(handler->zi_spa); kmem_free(handler, sizeof (inject_handler_t)); atomic_dec_32(&zio_injection_enabled); return (0); } void zio_inject_init(void) { rw_init(&inject_lock, NULL, RW_DEFAULT, NULL); mutex_init(&inject_delay_mtx, NULL, MUTEX_DEFAULT, NULL); list_create(&inject_handlers, sizeof (inject_handler_t), offsetof(inject_handler_t, zi_link)); } void zio_inject_fini(void) { list_destroy(&inject_handlers); mutex_destroy(&inject_delay_mtx); rw_destroy(&inject_lock); } #if defined(_KERNEL) EXPORT_SYMBOL(zio_injection_enabled); EXPORT_SYMBOL(zio_inject_fault); EXPORT_SYMBOL(zio_inject_list_next); EXPORT_SYMBOL(zio_clear_fault); EXPORT_SYMBOL(zio_handle_fault_injection); EXPORT_SYMBOL(zio_handle_device_injection); EXPORT_SYMBOL(zio_handle_label_injection); #endif