diff options
Diffstat (limited to 'sys/contrib/openzfs/module/zfs/vdev_label.c')
| -rw-r--r-- | sys/contrib/openzfs/module/zfs/vdev_label.c | 1901 |
1 files changed, 1901 insertions, 0 deletions
diff --git a/sys/contrib/openzfs/module/zfs/vdev_label.c b/sys/contrib/openzfs/module/zfs/vdev_label.c new file mode 100644 index 000000000000..8c7468255565 --- /dev/null +++ b/sys/contrib/openzfs/module/zfs/vdev_label.c @@ -0,0 +1,1901 @@ +/* + * 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 http://www.opensolaris.org/os/licensing. + * 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, 2020 by Delphix. All rights reserved. + * Copyright (c) 2017, Intel Corporation. + */ + +/* + * Virtual Device Labels + * --------------------- + * + * The vdev label serves several distinct purposes: + * + * 1. Uniquely identify this device as part of a ZFS pool and confirm its + * identity within the pool. + * + * 2. Verify that all the devices given in a configuration are present + * within the pool. + * + * 3. Determine the uberblock for the pool. + * + * 4. In case of an import operation, determine the configuration of the + * toplevel vdev of which it is a part. + * + * 5. If an import operation cannot find all the devices in the pool, + * provide enough information to the administrator to determine which + * devices are missing. + * + * It is important to note that while the kernel is responsible for writing the + * label, it only consumes the information in the first three cases. The + * latter information is only consumed in userland when determining the + * configuration to import a pool. + * + * + * Label Organization + * ------------------ + * + * Before describing the contents of the label, it's important to understand how + * the labels are written and updated with respect to the uberblock. + * + * When the pool configuration is altered, either because it was newly created + * or a device was added, we want to update all the labels such that we can deal + * with fatal failure at any point. To this end, each disk has two labels which + * are updated before and after the uberblock is synced. Assuming we have + * labels and an uberblock with the following transaction groups: + * + * L1 UB L2 + * +------+ +------+ +------+ + * | | | | | | + * | t10 | | t10 | | t10 | + * | | | | | | + * +------+ +------+ +------+ + * + * In this stable state, the labels and the uberblock were all updated within + * the same transaction group (10). Each label is mirrored and checksummed, so + * that we can detect when we fail partway through writing the label. + * + * In order to identify which labels are valid, the labels are written in the + * following manner: + * + * 1. For each vdev, update 'L1' to the new label + * 2. Update the uberblock + * 3. For each vdev, update 'L2' to the new label + * + * Given arbitrary failure, we can determine the correct label to use based on + * the transaction group. If we fail after updating L1 but before updating the + * UB, we will notice that L1's transaction group is greater than the uberblock, + * so L2 must be valid. If we fail after writing the uberblock but before + * writing L2, we will notice that L2's transaction group is less than L1, and + * therefore L1 is valid. + * + * Another added complexity is that not every label is updated when the config + * is synced. If we add a single device, we do not want to have to re-write + * every label for every device in the pool. This means that both L1 and L2 may + * be older than the pool uberblock, because the necessary information is stored + * on another vdev. + * + * + * On-disk Format + * -------------- + * + * The vdev label consists of two distinct parts, and is wrapped within the + * vdev_label_t structure. The label includes 8k of padding to permit legacy + * VTOC disk labels, but is otherwise ignored. + * + * The first half of the label is a packed nvlist which contains pool wide + * properties, per-vdev properties, and configuration information. It is + * described in more detail below. + * + * The latter half of the label consists of a redundant array of uberblocks. + * These uberblocks are updated whenever a transaction group is committed, + * or when the configuration is updated. When a pool is loaded, we scan each + * vdev for the 'best' uberblock. + * + * + * Configuration Information + * ------------------------- + * + * The nvlist describing the pool and vdev contains the following elements: + * + * version ZFS on-disk version + * name Pool name + * state Pool state + * txg Transaction group in which this label was written + * pool_guid Unique identifier for this pool + * vdev_tree An nvlist describing vdev tree. + * features_for_read + * An nvlist of the features necessary for reading the MOS. + * + * Each leaf device label also contains the following: + * + * top_guid Unique ID for top-level vdev in which this is contained + * guid Unique ID for the leaf vdev + * + * The 'vs' configuration follows the format described in 'spa_config.c'. + */ + +#include <sys/zfs_context.h> +#include <sys/spa.h> +#include <sys/spa_impl.h> +#include <sys/dmu.h> +#include <sys/zap.h> +#include <sys/vdev.h> +#include <sys/vdev_impl.h> +#include <sys/uberblock_impl.h> +#include <sys/metaslab.h> +#include <sys/metaslab_impl.h> +#include <sys/zio.h> +#include <sys/dsl_scan.h> +#include <sys/abd.h> +#include <sys/fs/zfs.h> + +/* + * Basic routines to read and write from a vdev label. + * Used throughout the rest of this file. + */ +uint64_t +vdev_label_offset(uint64_t psize, int l, uint64_t offset) +{ + ASSERT(offset < sizeof (vdev_label_t)); + ASSERT(P2PHASE_TYPED(psize, sizeof (vdev_label_t), uint64_t) == 0); + + return (offset + l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ? + 0 : psize - VDEV_LABELS * sizeof (vdev_label_t))); +} + +/* + * Returns back the vdev label associated with the passed in offset. + */ +int +vdev_label_number(uint64_t psize, uint64_t offset) +{ + int l; + + if (offset >= psize - VDEV_LABEL_END_SIZE) { + offset -= psize - VDEV_LABEL_END_SIZE; + offset += (VDEV_LABELS / 2) * sizeof (vdev_label_t); + } + l = offset / sizeof (vdev_label_t); + return (l < VDEV_LABELS ? l : -1); +} + +static void +vdev_label_read(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset, + uint64_t size, zio_done_func_t *done, void *private, int flags) +{ + ASSERT( + spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE || + spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE); + ASSERT(flags & ZIO_FLAG_CONFIG_WRITER); + + zio_nowait(zio_read_phys(zio, vd, + vdev_label_offset(vd->vdev_psize, l, offset), + size, buf, ZIO_CHECKSUM_LABEL, done, private, + ZIO_PRIORITY_SYNC_READ, flags, B_TRUE)); +} + +void +vdev_label_write(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset, + uint64_t size, zio_done_func_t *done, void *private, int flags) +{ + ASSERT( + spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE || + spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE); + ASSERT(flags & ZIO_FLAG_CONFIG_WRITER); + + zio_nowait(zio_write_phys(zio, vd, + vdev_label_offset(vd->vdev_psize, l, offset), + size, buf, ZIO_CHECKSUM_LABEL, done, private, + ZIO_PRIORITY_SYNC_WRITE, flags, B_TRUE)); +} + +/* + * Generate the nvlist representing this vdev's stats + */ +void +vdev_config_generate_stats(vdev_t *vd, nvlist_t *nv) +{ + nvlist_t *nvx; + vdev_stat_t *vs; + vdev_stat_ex_t *vsx; + + vs = kmem_alloc(sizeof (*vs), KM_SLEEP); + vsx = kmem_alloc(sizeof (*vsx), KM_SLEEP); + + vdev_get_stats_ex(vd, vs, vsx); + fnvlist_add_uint64_array(nv, ZPOOL_CONFIG_VDEV_STATS, + (uint64_t *)vs, sizeof (*vs) / sizeof (uint64_t)); + + /* + * Add extended stats into a special extended stats nvlist. This keeps + * all the extended stats nicely grouped together. The extended stats + * nvlist is then added to the main nvlist. + */ + nvx = fnvlist_alloc(); + + /* ZIOs in flight to disk */ + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_ACTIVE_QUEUE, + vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_READ]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_ACTIVE_QUEUE, + vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_WRITE]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_ACTIVE_QUEUE, + vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_READ]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_ACTIVE_QUEUE, + vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_WRITE]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_ACTIVE_QUEUE, + vsx->vsx_active_queue[ZIO_PRIORITY_SCRUB]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_ACTIVE_QUEUE, + vsx->vsx_active_queue[ZIO_PRIORITY_TRIM]); + + /* ZIOs pending */ + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_PEND_QUEUE, + vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_READ]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_PEND_QUEUE, + vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_WRITE]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_PEND_QUEUE, + vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_READ]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_PEND_QUEUE, + vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_WRITE]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_PEND_QUEUE, + vsx->vsx_pend_queue[ZIO_PRIORITY_SCRUB]); + + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_PEND_QUEUE, + vsx->vsx_pend_queue[ZIO_PRIORITY_TRIM]); + + /* Histograms */ + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_R_LAT_HISTO, + vsx->vsx_total_histo[ZIO_TYPE_READ], + ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_READ])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_W_LAT_HISTO, + vsx->vsx_total_histo[ZIO_TYPE_WRITE], + ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_WRITE])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_R_LAT_HISTO, + vsx->vsx_disk_histo[ZIO_TYPE_READ], + ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_READ])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_W_LAT_HISTO, + vsx->vsx_disk_histo[ZIO_TYPE_WRITE], + ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_WRITE])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_LAT_HISTO, + vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ], + ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_LAT_HISTO, + vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE], + ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_LAT_HISTO, + vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ], + ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_LAT_HISTO, + vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE], + ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SCRUB_LAT_HISTO, + vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB], + ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TRIM_LAT_HISTO, + vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM], + ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM])); + + /* Request sizes */ + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_R_HISTO, + vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ], + ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_W_HISTO, + vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE], + ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_R_HISTO, + vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ], + ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_W_HISTO, + vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE], + ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_SCRUB_HISTO, + vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB], + ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_TRIM_HISTO, + vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM], + ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_R_HISTO, + vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ], + ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_W_HISTO, + vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE], + ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_R_HISTO, + vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ], + ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_W_HISTO, + vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE], + ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_SCRUB_HISTO, + vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB], + ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB])); + + fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_TRIM_HISTO, + vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM], + ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM])); + + /* IO delays */ + fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SLOW_IOS, vs->vs_slow_ios); + + /* Add extended stats nvlist to main nvlist */ + fnvlist_add_nvlist(nv, ZPOOL_CONFIG_VDEV_STATS_EX, nvx); + + fnvlist_free(nvx); + kmem_free(vs, sizeof (*vs)); + kmem_free(vsx, sizeof (*vsx)); +} + +static void +root_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl) +{ + spa_t *spa = vd->vdev_spa; + + if (vd != spa->spa_root_vdev) + return; + + /* provide either current or previous scan information */ + pool_scan_stat_t ps; + if (spa_scan_get_stats(spa, &ps) == 0) { + fnvlist_add_uint64_array(nvl, + ZPOOL_CONFIG_SCAN_STATS, (uint64_t *)&ps, + sizeof (pool_scan_stat_t) / sizeof (uint64_t)); + } + + pool_removal_stat_t prs; + if (spa_removal_get_stats(spa, &prs) == 0) { + fnvlist_add_uint64_array(nvl, + ZPOOL_CONFIG_REMOVAL_STATS, (uint64_t *)&prs, + sizeof (prs) / sizeof (uint64_t)); + } + + pool_checkpoint_stat_t pcs; + if (spa_checkpoint_get_stats(spa, &pcs) == 0) { + fnvlist_add_uint64_array(nvl, + ZPOOL_CONFIG_CHECKPOINT_STATS, (uint64_t *)&pcs, + sizeof (pcs) / sizeof (uint64_t)); + } +} + +static void +top_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl) +{ + if (vd == vd->vdev_top) { + vdev_rebuild_stat_t vrs; + if (vdev_rebuild_get_stats(vd, &vrs) == 0) { + fnvlist_add_uint64_array(nvl, + ZPOOL_CONFIG_REBUILD_STATS, (uint64_t *)&vrs, + sizeof (vrs) / sizeof (uint64_t)); + } + } +} + +/* + * Generate the nvlist representing this vdev's config. + */ +nvlist_t * +vdev_config_generate(spa_t *spa, vdev_t *vd, boolean_t getstats, + vdev_config_flag_t flags) +{ + nvlist_t *nv = NULL; + vdev_indirect_config_t *vic = &vd->vdev_indirect_config; + + nv = fnvlist_alloc(); + + fnvlist_add_string(nv, ZPOOL_CONFIG_TYPE, vd->vdev_ops->vdev_op_type); + if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE))) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_ID, vd->vdev_id); + fnvlist_add_uint64(nv, ZPOOL_CONFIG_GUID, vd->vdev_guid); + + if (vd->vdev_path != NULL) + fnvlist_add_string(nv, ZPOOL_CONFIG_PATH, vd->vdev_path); + + if (vd->vdev_devid != NULL) + fnvlist_add_string(nv, ZPOOL_CONFIG_DEVID, vd->vdev_devid); + + if (vd->vdev_physpath != NULL) + fnvlist_add_string(nv, ZPOOL_CONFIG_PHYS_PATH, + vd->vdev_physpath); + + if (vd->vdev_enc_sysfs_path != NULL) + fnvlist_add_string(nv, ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH, + vd->vdev_enc_sysfs_path); + + if (vd->vdev_fru != NULL) + fnvlist_add_string(nv, ZPOOL_CONFIG_FRU, vd->vdev_fru); + + if (vd->vdev_nparity != 0) { + ASSERT(strcmp(vd->vdev_ops->vdev_op_type, + VDEV_TYPE_RAIDZ) == 0); + + /* + * Make sure someone hasn't managed to sneak a fancy new vdev + * into a crufty old storage pool. + */ + ASSERT(vd->vdev_nparity == 1 || + (vd->vdev_nparity <= 2 && + spa_version(spa) >= SPA_VERSION_RAIDZ2) || + (vd->vdev_nparity <= 3 && + spa_version(spa) >= SPA_VERSION_RAIDZ3)); + + /* + * Note that we'll add the nparity tag even on storage pools + * that only support a single parity device -- older software + * will just ignore it. + */ + fnvlist_add_uint64(nv, ZPOOL_CONFIG_NPARITY, vd->vdev_nparity); + } + + if (vd->vdev_wholedisk != -1ULL) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK, + vd->vdev_wholedisk); + + if (vd->vdev_not_present && !(flags & VDEV_CONFIG_MISSING)) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_NOT_PRESENT, 1); + + if (vd->vdev_isspare) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_SPARE, 1); + + if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE)) && + vd == vd->vdev_top) { + fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_ARRAY, + vd->vdev_ms_array); + fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_SHIFT, + vd->vdev_ms_shift); + fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASHIFT, vd->vdev_ashift); + fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASIZE, + vd->vdev_asize); + fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_LOG, vd->vdev_islog); + if (vd->vdev_removing) { + fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVING, + vd->vdev_removing); + } + + /* zpool command expects alloc class data */ + if (getstats && vd->vdev_alloc_bias != VDEV_BIAS_NONE) { + const char *bias = NULL; + + switch (vd->vdev_alloc_bias) { + case VDEV_BIAS_LOG: + bias = VDEV_ALLOC_BIAS_LOG; + break; + case VDEV_BIAS_SPECIAL: + bias = VDEV_ALLOC_BIAS_SPECIAL; + break; + case VDEV_BIAS_DEDUP: + bias = VDEV_ALLOC_BIAS_DEDUP; + break; + default: + ASSERT3U(vd->vdev_alloc_bias, ==, + VDEV_BIAS_NONE); + } + fnvlist_add_string(nv, ZPOOL_CONFIG_ALLOCATION_BIAS, + bias); + } + } + + if (vd->vdev_dtl_sm != NULL) { + fnvlist_add_uint64(nv, ZPOOL_CONFIG_DTL, + space_map_object(vd->vdev_dtl_sm)); + } + + if (vic->vic_mapping_object != 0) { + fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_OBJECT, + vic->vic_mapping_object); + } + + if (vic->vic_births_object != 0) { + fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_BIRTHS, + vic->vic_births_object); + } + + if (vic->vic_prev_indirect_vdev != UINT64_MAX) { + fnvlist_add_uint64(nv, ZPOOL_CONFIG_PREV_INDIRECT_VDEV, + vic->vic_prev_indirect_vdev); + } + + if (vd->vdev_crtxg) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_CREATE_TXG, vd->vdev_crtxg); + + if (vd->vdev_expansion_time) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_EXPANSION_TIME, + vd->vdev_expansion_time); + + if (flags & VDEV_CONFIG_MOS) { + if (vd->vdev_leaf_zap != 0) { + ASSERT(vd->vdev_ops->vdev_op_leaf); + fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_LEAF_ZAP, + vd->vdev_leaf_zap); + } + + if (vd->vdev_top_zap != 0) { + ASSERT(vd == vd->vdev_top); + fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_TOP_ZAP, + vd->vdev_top_zap); + } + + if (vd->vdev_resilver_deferred) { + ASSERT(vd->vdev_ops->vdev_op_leaf); + ASSERT(spa->spa_resilver_deferred); + fnvlist_add_boolean(nv, ZPOOL_CONFIG_RESILVER_DEFER); + } + } + + if (getstats) { + vdev_config_generate_stats(vd, nv); + + root_vdev_actions_getprogress(vd, nv); + top_vdev_actions_getprogress(vd, nv); + + /* + * Note: this can be called from open context + * (spa_get_stats()), so we need the rwlock to prevent + * the mapping from being changed by condensing. + */ + rw_enter(&vd->vdev_indirect_rwlock, RW_READER); + if (vd->vdev_indirect_mapping != NULL) { + ASSERT(vd->vdev_indirect_births != NULL); + vdev_indirect_mapping_t *vim = + vd->vdev_indirect_mapping; + fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE, + vdev_indirect_mapping_size(vim)); + } + rw_exit(&vd->vdev_indirect_rwlock); + if (vd->vdev_mg != NULL && + vd->vdev_mg->mg_fragmentation != ZFS_FRAG_INVALID) { + /* + * Compute approximately how much memory would be used + * for the indirect mapping if this device were to + * be removed. + * + * Note: If the frag metric is invalid, then not + * enough metaslabs have been converted to have + * histograms. + */ + uint64_t seg_count = 0; + uint64_t to_alloc = vd->vdev_stat.vs_alloc; + + /* + * There are the same number of allocated segments + * as free segments, so we will have at least one + * entry per free segment. However, small free + * segments (smaller than vdev_removal_max_span) + * will be combined with adjacent allocated segments + * as a single mapping. + */ + for (int i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) { + if (1ULL << (i + 1) < vdev_removal_max_span) { + to_alloc += + vd->vdev_mg->mg_histogram[i] << + (i + 1); + } else { + seg_count += + vd->vdev_mg->mg_histogram[i]; + } + } + + /* + * The maximum length of a mapping is + * zfs_remove_max_segment, so we need at least one entry + * per zfs_remove_max_segment of allocated data. + */ + seg_count += to_alloc / spa_remove_max_segment(spa); + + fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE, + seg_count * + sizeof (vdev_indirect_mapping_entry_phys_t)); + } + } + + if (!vd->vdev_ops->vdev_op_leaf) { + nvlist_t **child; + int c, idx; + + ASSERT(!vd->vdev_ishole); + + child = kmem_alloc(vd->vdev_children * sizeof (nvlist_t *), + KM_SLEEP); + + for (c = 0, idx = 0; c < vd->vdev_children; c++) { + vdev_t *cvd = vd->vdev_child[c]; + + /* + * If we're generating an nvlist of removing + * vdevs then skip over any device which is + * not being removed. + */ + if ((flags & VDEV_CONFIG_REMOVING) && + !cvd->vdev_removing) + continue; + + child[idx++] = vdev_config_generate(spa, cvd, + getstats, flags); + } + + if (idx) { + fnvlist_add_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN, + child, idx); + } + + for (c = 0; c < idx; c++) + nvlist_free(child[c]); + + kmem_free(child, vd->vdev_children * sizeof (nvlist_t *)); + + } else { + const char *aux = NULL; + + if (vd->vdev_offline && !vd->vdev_tmpoffline) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_OFFLINE, B_TRUE); + if (vd->vdev_resilver_txg != 0) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_RESILVER_TXG, + vd->vdev_resilver_txg); + if (vd->vdev_rebuild_txg != 0) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_REBUILD_TXG, + vd->vdev_rebuild_txg); + if (vd->vdev_faulted) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_FAULTED, B_TRUE); + if (vd->vdev_degraded) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_DEGRADED, B_TRUE); + if (vd->vdev_removed) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVED, B_TRUE); + if (vd->vdev_unspare) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_UNSPARE, B_TRUE); + if (vd->vdev_ishole) + fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_HOLE, B_TRUE); + + /* Set the reason why we're FAULTED/DEGRADED. */ + switch (vd->vdev_stat.vs_aux) { + case VDEV_AUX_ERR_EXCEEDED: + aux = "err_exceeded"; + break; + + case VDEV_AUX_EXTERNAL: + aux = "external"; + break; + } + + if (aux != NULL && !vd->vdev_tmpoffline) { + fnvlist_add_string(nv, ZPOOL_CONFIG_AUX_STATE, aux); + } else { + /* + * We're healthy - clear any previous AUX_STATE values. + */ + if (nvlist_exists(nv, ZPOOL_CONFIG_AUX_STATE)) + nvlist_remove_all(nv, ZPOOL_CONFIG_AUX_STATE); + } + + if (vd->vdev_splitting && vd->vdev_orig_guid != 0LL) { + fnvlist_add_uint64(nv, ZPOOL_CONFIG_ORIG_GUID, + vd->vdev_orig_guid); + } + } + + return (nv); +} + +/* + * Generate a view of the top-level vdevs. If we currently have holes + * in the namespace, then generate an array which contains a list of holey + * vdevs. Additionally, add the number of top-level children that currently + * exist. + */ +void +vdev_top_config_generate(spa_t *spa, nvlist_t *config) +{ + vdev_t *rvd = spa->spa_root_vdev; + uint64_t *array; + uint_t c, idx; + + array = kmem_alloc(rvd->vdev_children * sizeof (uint64_t), KM_SLEEP); + + for (c = 0, idx = 0; c < rvd->vdev_children; c++) { + vdev_t *tvd = rvd->vdev_child[c]; + + if (tvd->vdev_ishole) { + array[idx++] = c; + } + } + + if (idx) { + VERIFY(nvlist_add_uint64_array(config, ZPOOL_CONFIG_HOLE_ARRAY, + array, idx) == 0); + } + + VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN, + rvd->vdev_children) == 0); + + kmem_free(array, rvd->vdev_children * sizeof (uint64_t)); +} + +/* + * Returns the configuration from the label of the given vdev. For vdevs + * which don't have a txg value stored on their label (i.e. spares/cache) + * or have not been completely initialized (txg = 0) just return + * the configuration from the first valid label we find. Otherwise, + * find the most up-to-date label that does not exceed the specified + * 'txg' value. + */ +nvlist_t * +vdev_label_read_config(vdev_t *vd, uint64_t txg) +{ + spa_t *spa = vd->vdev_spa; + nvlist_t *config = NULL; + vdev_phys_t *vp; + abd_t *vp_abd; + zio_t *zio; + uint64_t best_txg = 0; + uint64_t label_txg = 0; + int error = 0; + int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | + ZIO_FLAG_SPECULATIVE; + + ASSERT(spa_config_held(spa, SCL_STATE_ALL, RW_WRITER) == SCL_STATE_ALL); + + if (!vdev_readable(vd)) + return (NULL); + + vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); + vp = abd_to_buf(vp_abd); + +retry: + for (int l = 0; l < VDEV_LABELS; l++) { + nvlist_t *label = NULL; + + zio = zio_root(spa, NULL, NULL, flags); + + vdev_label_read(zio, vd, l, vp_abd, + offsetof(vdev_label_t, vl_vdev_phys), + sizeof (vdev_phys_t), NULL, NULL, flags); + + if (zio_wait(zio) == 0 && + nvlist_unpack(vp->vp_nvlist, sizeof (vp->vp_nvlist), + &label, 0) == 0) { + /* + * Auxiliary vdevs won't have txg values in their + * labels and newly added vdevs may not have been + * completely initialized so just return the + * configuration from the first valid label we + * encounter. + */ + error = nvlist_lookup_uint64(label, + ZPOOL_CONFIG_POOL_TXG, &label_txg); + if ((error || label_txg == 0) && !config) { + config = label; + break; + } else if (label_txg <= txg && label_txg > best_txg) { + best_txg = label_txg; + nvlist_free(config); + config = fnvlist_dup(label); + } + } + + if (label != NULL) { + nvlist_free(label); + label = NULL; + } + } + + if (config == NULL && !(flags & ZIO_FLAG_TRYHARD)) { + flags |= ZIO_FLAG_TRYHARD; + goto retry; + } + + /* + * We found a valid label but it didn't pass txg restrictions. + */ + if (config == NULL && label_txg != 0) { + vdev_dbgmsg(vd, "label discarded as txg is too large " + "(%llu > %llu)", (u_longlong_t)label_txg, + (u_longlong_t)txg); + } + + abd_free(vp_abd); + + return (config); +} + +/* + * Determine if a device is in use. The 'spare_guid' parameter will be filled + * in with the device guid if this spare is active elsewhere on the system. + */ +static boolean_t +vdev_inuse(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason, + uint64_t *spare_guid, uint64_t *l2cache_guid) +{ + spa_t *spa = vd->vdev_spa; + uint64_t state, pool_guid, device_guid, txg, spare_pool; + uint64_t vdtxg = 0; + nvlist_t *label; + + if (spare_guid) + *spare_guid = 0ULL; + if (l2cache_guid) + *l2cache_guid = 0ULL; + + /* + * Read the label, if any, and perform some basic sanity checks. + */ + if ((label = vdev_label_read_config(vd, -1ULL)) == NULL) + return (B_FALSE); + + (void) nvlist_lookup_uint64(label, ZPOOL_CONFIG_CREATE_TXG, + &vdtxg); + + if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_STATE, + &state) != 0 || + nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID, + &device_guid) != 0) { + nvlist_free(label); + return (B_FALSE); + } + + if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && + (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID, + &pool_guid) != 0 || + nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG, + &txg) != 0)) { + nvlist_free(label); + return (B_FALSE); + } + + nvlist_free(label); + + /* + * Check to see if this device indeed belongs to the pool it claims to + * be a part of. The only way this is allowed is if the device is a hot + * spare (which we check for later on). + */ + if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && + !spa_guid_exists(pool_guid, device_guid) && + !spa_spare_exists(device_guid, NULL, NULL) && + !spa_l2cache_exists(device_guid, NULL)) + return (B_FALSE); + + /* + * If the transaction group is zero, then this an initialized (but + * unused) label. This is only an error if the create transaction + * on-disk is the same as the one we're using now, in which case the + * user has attempted to add the same vdev multiple times in the same + * transaction. + */ + if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && + txg == 0 && vdtxg == crtxg) + return (B_TRUE); + + /* + * Check to see if this is a spare device. We do an explicit check for + * spa_has_spare() here because it may be on our pending list of spares + * to add. We also check if it is an l2cache device. + */ + if (spa_spare_exists(device_guid, &spare_pool, NULL) || + spa_has_spare(spa, device_guid)) { + if (spare_guid) + *spare_guid = device_guid; + + switch (reason) { + case VDEV_LABEL_CREATE: + case VDEV_LABEL_L2CACHE: + return (B_TRUE); + + case VDEV_LABEL_REPLACE: + return (!spa_has_spare(spa, device_guid) || + spare_pool != 0ULL); + + case VDEV_LABEL_SPARE: + return (spa_has_spare(spa, device_guid)); + default: + break; + } + } + + /* + * Check to see if this is an l2cache device. + */ + if (spa_l2cache_exists(device_guid, NULL)) + return (B_TRUE); + + /* + * We can't rely on a pool's state if it's been imported + * read-only. Instead we look to see if the pools is marked + * read-only in the namespace and set the state to active. + */ + if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && + (spa = spa_by_guid(pool_guid, device_guid)) != NULL && + spa_mode(spa) == SPA_MODE_READ) + state = POOL_STATE_ACTIVE; + + /* + * If the device is marked ACTIVE, then this device is in use by another + * pool on the system. + */ + return (state == POOL_STATE_ACTIVE); +} + +/* + * Initialize a vdev label. We check to make sure each leaf device is not in + * use, and writable. We put down an initial label which we will later + * overwrite with a complete label. Note that it's important to do this + * sequentially, not in parallel, so that we catch cases of multiple use of the + * same leaf vdev in the vdev we're creating -- e.g. mirroring a disk with + * itself. + */ +int +vdev_label_init(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason) +{ + spa_t *spa = vd->vdev_spa; + nvlist_t *label; + vdev_phys_t *vp; + abd_t *vp_abd; + abd_t *bootenv; + uberblock_t *ub; + abd_t *ub_abd; + zio_t *zio; + char *buf; + size_t buflen; + int error; + uint64_t spare_guid = 0, l2cache_guid = 0; + int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; + + ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); + + for (int c = 0; c < vd->vdev_children; c++) + if ((error = vdev_label_init(vd->vdev_child[c], + crtxg, reason)) != 0) + return (error); + + /* Track the creation time for this vdev */ + vd->vdev_crtxg = crtxg; + + if (!vd->vdev_ops->vdev_op_leaf || !spa_writeable(spa)) + return (0); + + /* + * Dead vdevs cannot be initialized. + */ + if (vdev_is_dead(vd)) + return (SET_ERROR(EIO)); + + /* + * Determine if the vdev is in use. + */ + if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPLIT && + vdev_inuse(vd, crtxg, reason, &spare_guid, &l2cache_guid)) + return (SET_ERROR(EBUSY)); + + /* + * If this is a request to add or replace a spare or l2cache device + * that is in use elsewhere on the system, then we must update the + * guid (which was initialized to a random value) to reflect the + * actual GUID (which is shared between multiple pools). + */ + if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_L2CACHE && + spare_guid != 0ULL) { + uint64_t guid_delta = spare_guid - vd->vdev_guid; + + vd->vdev_guid += guid_delta; + + for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent) + pvd->vdev_guid_sum += guid_delta; + + /* + * If this is a replacement, then we want to fallthrough to the + * rest of the code. If we're adding a spare, then it's already + * labeled appropriately and we can just return. + */ + if (reason == VDEV_LABEL_SPARE) + return (0); + ASSERT(reason == VDEV_LABEL_REPLACE || + reason == VDEV_LABEL_SPLIT); + } + + if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPARE && + l2cache_guid != 0ULL) { + uint64_t guid_delta = l2cache_guid - vd->vdev_guid; + + vd->vdev_guid += guid_delta; + + for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent) + pvd->vdev_guid_sum += guid_delta; + + /* + * If this is a replacement, then we want to fallthrough to the + * rest of the code. If we're adding an l2cache, then it's + * already labeled appropriately and we can just return. + */ + if (reason == VDEV_LABEL_L2CACHE) + return (0); + ASSERT(reason == VDEV_LABEL_REPLACE); + } + + /* + * Initialize its label. + */ + vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); + abd_zero(vp_abd, sizeof (vdev_phys_t)); + vp = abd_to_buf(vp_abd); + + /* + * Generate a label describing the pool and our top-level vdev. + * We mark it as being from txg 0 to indicate that it's not + * really part of an active pool just yet. The labels will + * be written again with a meaningful txg by spa_sync(). + */ + if (reason == VDEV_LABEL_SPARE || + (reason == VDEV_LABEL_REMOVE && vd->vdev_isspare)) { + /* + * For inactive hot spares, we generate a special label that + * identifies as a mutually shared hot spare. We write the + * label if we are adding a hot spare, or if we are removing an + * active hot spare (in which case we want to revert the + * labels). + */ + VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0); + + VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION, + spa_version(spa)) == 0); + VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE, + POOL_STATE_SPARE) == 0); + VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID, + vd->vdev_guid) == 0); + } else if (reason == VDEV_LABEL_L2CACHE || + (reason == VDEV_LABEL_REMOVE && vd->vdev_isl2cache)) { + /* + * For level 2 ARC devices, add a special label. + */ + VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0); + + VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION, + spa_version(spa)) == 0); + VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE, + POOL_STATE_L2CACHE) == 0); + VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID, + vd->vdev_guid) == 0); + } else { + uint64_t txg = 0ULL; + + if (reason == VDEV_LABEL_SPLIT) + txg = spa->spa_uberblock.ub_txg; + label = spa_config_generate(spa, vd, txg, B_FALSE); + + /* + * Add our creation time. This allows us to detect multiple + * vdev uses as described above, and automatically expires if we + * fail. + */ + VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_CREATE_TXG, + crtxg) == 0); + } + + buf = vp->vp_nvlist; + buflen = sizeof (vp->vp_nvlist); + + error = nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP); + if (error != 0) { + nvlist_free(label); + abd_free(vp_abd); + /* EFAULT means nvlist_pack ran out of room */ + return (SET_ERROR(error == EFAULT ? ENAMETOOLONG : EINVAL)); + } + + /* + * Initialize uberblock template. + */ + ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_RING, B_TRUE); + abd_zero(ub_abd, VDEV_UBERBLOCK_RING); + abd_copy_from_buf(ub_abd, &spa->spa_uberblock, sizeof (uberblock_t)); + ub = abd_to_buf(ub_abd); + ub->ub_txg = 0; + + /* Initialize the 2nd padding area. */ + bootenv = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE); + abd_zero(bootenv, VDEV_PAD_SIZE); + + /* + * Write everything in parallel. + */ +retry: + zio = zio_root(spa, NULL, NULL, flags); + + for (int l = 0; l < VDEV_LABELS; l++) { + + vdev_label_write(zio, vd, l, vp_abd, + offsetof(vdev_label_t, vl_vdev_phys), + sizeof (vdev_phys_t), NULL, NULL, flags); + + /* + * Skip the 1st padding area. + * Zero out the 2nd padding area where it might have + * left over data from previous filesystem format. + */ + vdev_label_write(zio, vd, l, bootenv, + offsetof(vdev_label_t, vl_be), + VDEV_PAD_SIZE, NULL, NULL, flags); + + vdev_label_write(zio, vd, l, ub_abd, + offsetof(vdev_label_t, vl_uberblock), + VDEV_UBERBLOCK_RING, NULL, NULL, flags); + } + + error = zio_wait(zio); + + if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) { + flags |= ZIO_FLAG_TRYHARD; + goto retry; + } + + nvlist_free(label); + abd_free(bootenv); + abd_free(ub_abd); + abd_free(vp_abd); + + /* + * If this vdev hasn't been previously identified as a spare, then we + * mark it as such only if a) we are labeling it as a spare, or b) it + * exists as a spare elsewhere in the system. Do the same for + * level 2 ARC devices. + */ + if (error == 0 && !vd->vdev_isspare && + (reason == VDEV_LABEL_SPARE || + spa_spare_exists(vd->vdev_guid, NULL, NULL))) + spa_spare_add(vd); + + if (error == 0 && !vd->vdev_isl2cache && + (reason == VDEV_LABEL_L2CACHE || + spa_l2cache_exists(vd->vdev_guid, NULL))) + spa_l2cache_add(vd); + + return (error); +} + +/* + * Done callback for vdev_label_read_bootenv_impl. If this is the first + * callback to finish, store our abd in the callback pointer. Otherwise, we + * just free our abd and return. + */ +static void +vdev_label_read_bootenv_done(zio_t *zio) +{ + zio_t *rio = zio->io_private; + abd_t **cbp = rio->io_private; + + ASSERT3U(zio->io_size, ==, VDEV_PAD_SIZE); + + if (zio->io_error == 0) { + mutex_enter(&rio->io_lock); + if (*cbp == NULL) { + /* Will free this buffer in vdev_label_read_bootenv. */ + *cbp = zio->io_abd; + } else { + abd_free(zio->io_abd); + } + mutex_exit(&rio->io_lock); + } else { + abd_free(zio->io_abd); + } +} + +static void +vdev_label_read_bootenv_impl(zio_t *zio, vdev_t *vd, int flags) +{ + for (int c = 0; c < vd->vdev_children; c++) + vdev_label_read_bootenv_impl(zio, vd->vdev_child[c], flags); + + /* + * We just use the first label that has a correct checksum; the + * bootloader should have rewritten them all to be the same on boot, + * and any changes we made since boot have been the same across all + * labels. + * + * While grub supports writing to all four labels, other bootloaders + * don't, so we only use the first two labels to store boot + * information. + */ + if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd)) { + for (int l = 0; l < VDEV_LABELS / 2; l++) { + vdev_label_read(zio, vd, l, + abd_alloc_linear(VDEV_PAD_SIZE, B_FALSE), + offsetof(vdev_label_t, vl_be), VDEV_PAD_SIZE, + vdev_label_read_bootenv_done, zio, flags); + } + } +} + +int +vdev_label_read_bootenv(vdev_t *rvd, nvlist_t *command) +{ + spa_t *spa = rvd->vdev_spa; + abd_t *abd = NULL; + int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | + ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD; + + ASSERT(command); + ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); + + zio_t *zio = zio_root(spa, NULL, &abd, flags); + vdev_label_read_bootenv_impl(zio, rvd, flags); + int err = zio_wait(zio); + + if (abd != NULL) { + vdev_boot_envblock_t *vbe = abd_to_buf(abd); + if (vbe->vbe_version != VB_RAW) { + abd_free(abd); + return (SET_ERROR(ENOTSUP)); + } + vbe->vbe_bootenv[sizeof (vbe->vbe_bootenv) - 1] = '\0'; + fnvlist_add_string(command, "envmap", vbe->vbe_bootenv); + /* abd was allocated in vdev_label_read_bootenv_impl() */ + abd_free(abd); + /* If we managed to read any successfully, return success. */ + return (0); + } + return (err); +} + +int +vdev_label_write_bootenv(vdev_t *vd, char *envmap) +{ + zio_t *zio; + spa_t *spa = vd->vdev_spa; + vdev_boot_envblock_t *bootenv; + int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; + int error = ENXIO; + + if (strlen(envmap) >= sizeof (bootenv->vbe_bootenv)) { + return (SET_ERROR(E2BIG)); + } + + ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); + + for (int c = 0; c < vd->vdev_children; c++) { + int child_err = vdev_label_write_bootenv(vd->vdev_child[c], + envmap); + /* + * As long as any of the disks managed to write all of their + * labels successfully, return success. + */ + if (child_err == 0) + error = child_err; + } + + if (!vd->vdev_ops->vdev_op_leaf || vdev_is_dead(vd) || + !vdev_writeable(vd)) { + return (error); + } + ASSERT3U(sizeof (*bootenv), ==, VDEV_PAD_SIZE); + abd_t *abd = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE); + abd_zero(abd, VDEV_PAD_SIZE); + bootenv = abd_borrow_buf_copy(abd, VDEV_PAD_SIZE); + + char *buf = bootenv->vbe_bootenv; + (void) strlcpy(buf, envmap, sizeof (bootenv->vbe_bootenv)); + bootenv->vbe_version = VB_RAW; + abd_return_buf_copy(abd, bootenv, VDEV_PAD_SIZE); + +retry: + zio = zio_root(spa, NULL, NULL, flags); + for (int l = 0; l < VDEV_LABELS / 2; l++) { + vdev_label_write(zio, vd, l, abd, + offsetof(vdev_label_t, vl_be), + VDEV_PAD_SIZE, NULL, NULL, flags); + } + + error = zio_wait(zio); + if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) { + flags |= ZIO_FLAG_TRYHARD; + goto retry; + } + + abd_free(abd); + return (error); +} + +/* + * ========================================================================== + * uberblock load/sync + * ========================================================================== + */ + +/* + * Consider the following situation: txg is safely synced to disk. We've + * written the first uberblock for txg + 1, and then we lose power. When we + * come back up, we fail to see the uberblock for txg + 1 because, say, + * it was on a mirrored device and the replica to which we wrote txg + 1 + * is now offline. If we then make some changes and sync txg + 1, and then + * the missing replica comes back, then for a few seconds we'll have two + * conflicting uberblocks on disk with the same txg. The solution is simple: + * among uberblocks with equal txg, choose the one with the latest timestamp. + */ +static int +vdev_uberblock_compare(const uberblock_t *ub1, const uberblock_t *ub2) +{ + int cmp = TREE_CMP(ub1->ub_txg, ub2->ub_txg); + + if (likely(cmp)) + return (cmp); + + cmp = TREE_CMP(ub1->ub_timestamp, ub2->ub_timestamp); + if (likely(cmp)) + return (cmp); + + /* + * If MMP_VALID(ub) && MMP_SEQ_VALID(ub) then the host has an MMP-aware + * ZFS, e.g. zfsonlinux >= 0.7. + * + * If one ub has MMP and the other does not, they were written by + * different hosts, which matters for MMP. So we treat no MMP/no SEQ as + * a 0 value. + * + * Since timestamp and txg are the same if we get this far, either is + * acceptable for importing the pool. + */ + unsigned int seq1 = 0; + unsigned int seq2 = 0; + + if (MMP_VALID(ub1) && MMP_SEQ_VALID(ub1)) + seq1 = MMP_SEQ(ub1); + + if (MMP_VALID(ub2) && MMP_SEQ_VALID(ub2)) + seq2 = MMP_SEQ(ub2); + + return (TREE_CMP(seq1, seq2)); +} + +struct ubl_cbdata { + uberblock_t *ubl_ubbest; /* Best uberblock */ + vdev_t *ubl_vd; /* vdev associated with the above */ +}; + +static void +vdev_uberblock_load_done(zio_t *zio) +{ + vdev_t *vd = zio->io_vd; + spa_t *spa = zio->io_spa; + zio_t *rio = zio->io_private; + uberblock_t *ub = abd_to_buf(zio->io_abd); + struct ubl_cbdata *cbp = rio->io_private; + + ASSERT3U(zio->io_size, ==, VDEV_UBERBLOCK_SIZE(vd)); + + if (zio->io_error == 0 && uberblock_verify(ub) == 0) { + mutex_enter(&rio->io_lock); + if (ub->ub_txg <= spa->spa_load_max_txg && + vdev_uberblock_compare(ub, cbp->ubl_ubbest) > 0) { + /* + * Keep track of the vdev in which this uberblock + * was found. We will use this information later + * to obtain the config nvlist associated with + * this uberblock. + */ + *cbp->ubl_ubbest = *ub; + cbp->ubl_vd = vd; + } + mutex_exit(&rio->io_lock); + } + + abd_free(zio->io_abd); +} + +static void +vdev_uberblock_load_impl(zio_t *zio, vdev_t *vd, int flags, + struct ubl_cbdata *cbp) +{ + for (int c = 0; c < vd->vdev_children; c++) + vdev_uberblock_load_impl(zio, vd->vdev_child[c], flags, cbp); + + if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd)) { + for (int l = 0; l < VDEV_LABELS; l++) { + for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) { + vdev_label_read(zio, vd, l, + abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), + B_TRUE), VDEV_UBERBLOCK_OFFSET(vd, n), + VDEV_UBERBLOCK_SIZE(vd), + vdev_uberblock_load_done, zio, flags); + } + } + } +} + +/* + * Reads the 'best' uberblock from disk along with its associated + * configuration. First, we read the uberblock array of each label of each + * vdev, keeping track of the uberblock with the highest txg in each array. + * Then, we read the configuration from the same vdev as the best uberblock. + */ +void +vdev_uberblock_load(vdev_t *rvd, uberblock_t *ub, nvlist_t **config) +{ + zio_t *zio; + spa_t *spa = rvd->vdev_spa; + struct ubl_cbdata cb; + int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | + ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD; + + ASSERT(ub); + ASSERT(config); + + bzero(ub, sizeof (uberblock_t)); + *config = NULL; + + cb.ubl_ubbest = ub; + cb.ubl_vd = NULL; + + spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); + zio = zio_root(spa, NULL, &cb, flags); + vdev_uberblock_load_impl(zio, rvd, flags, &cb); + (void) zio_wait(zio); + + /* + * It's possible that the best uberblock was discovered on a label + * that has a configuration which was written in a future txg. + * Search all labels on this vdev to find the configuration that + * matches the txg for our uberblock. + */ + if (cb.ubl_vd != NULL) { + vdev_dbgmsg(cb.ubl_vd, "best uberblock found for spa %s. " + "txg %llu", spa->spa_name, (u_longlong_t)ub->ub_txg); + + *config = vdev_label_read_config(cb.ubl_vd, ub->ub_txg); + if (*config == NULL && spa->spa_extreme_rewind) { + vdev_dbgmsg(cb.ubl_vd, "failed to read label config. " + "Trying again without txg restrictions."); + *config = vdev_label_read_config(cb.ubl_vd, UINT64_MAX); + } + if (*config == NULL) { + vdev_dbgmsg(cb.ubl_vd, "failed to read label config"); + } + } + spa_config_exit(spa, SCL_ALL, FTAG); +} + +/* + * For use when a leaf vdev is expanded. + * The location of labels 2 and 3 changed, and at the new location the + * uberblock rings are either empty or contain garbage. The sync will write + * new configs there because the vdev is dirty, but expansion also needs the + * uberblock rings copied. Read them from label 0 which did not move. + * + * Since the point is to populate labels {2,3} with valid uberblocks, + * we zero uberblocks we fail to read or which are not valid. + */ + +static void +vdev_copy_uberblocks(vdev_t *vd) +{ + abd_t *ub_abd; + zio_t *write_zio; + int locks = (SCL_L2ARC | SCL_ZIO); + int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | + ZIO_FLAG_SPECULATIVE; + + ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_READER) == + SCL_STATE); + ASSERT(vd->vdev_ops->vdev_op_leaf); + + spa_config_enter(vd->vdev_spa, locks, FTAG, RW_READER); + + ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), B_TRUE); + + write_zio = zio_root(vd->vdev_spa, NULL, NULL, flags); + for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) { + const int src_label = 0; + zio_t *zio; + + zio = zio_root(vd->vdev_spa, NULL, NULL, flags); + vdev_label_read(zio, vd, src_label, ub_abd, + VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd), + NULL, NULL, flags); + + if (zio_wait(zio) || uberblock_verify(abd_to_buf(ub_abd))) + abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd)); + + for (int l = 2; l < VDEV_LABELS; l++) + vdev_label_write(write_zio, vd, l, ub_abd, + VDEV_UBERBLOCK_OFFSET(vd, n), + VDEV_UBERBLOCK_SIZE(vd), NULL, NULL, + flags | ZIO_FLAG_DONT_PROPAGATE); + } + (void) zio_wait(write_zio); + + spa_config_exit(vd->vdev_spa, locks, FTAG); + + abd_free(ub_abd); +} + +/* + * On success, increment root zio's count of good writes. + * We only get credit for writes to known-visible vdevs; see spa_vdev_add(). + */ +static void +vdev_uberblock_sync_done(zio_t *zio) +{ + uint64_t *good_writes = zio->io_private; + + if (zio->io_error == 0 && zio->io_vd->vdev_top->vdev_ms_array != 0) + atomic_inc_64(good_writes); +} + +/* + * Write the uberblock to all labels of all leaves of the specified vdev. + */ +static void +vdev_uberblock_sync(zio_t *zio, uint64_t *good_writes, + uberblock_t *ub, vdev_t *vd, int flags) +{ + for (uint64_t c = 0; c < vd->vdev_children; c++) { + vdev_uberblock_sync(zio, good_writes, + ub, vd->vdev_child[c], flags); + } + + if (!vd->vdev_ops->vdev_op_leaf) + return; + + if (!vdev_writeable(vd)) + return; + + /* If the vdev was expanded, need to copy uberblock rings. */ + if (vd->vdev_state == VDEV_STATE_HEALTHY && + vd->vdev_copy_uberblocks == B_TRUE) { + vdev_copy_uberblocks(vd); + vd->vdev_copy_uberblocks = B_FALSE; + } + + int m = spa_multihost(vd->vdev_spa) ? MMP_BLOCKS_PER_LABEL : 0; + int n = ub->ub_txg % (VDEV_UBERBLOCK_COUNT(vd) - m); + + /* Copy the uberblock_t into the ABD */ + abd_t *ub_abd = abd_alloc_for_io(VDEV_UBERBLOCK_SIZE(vd), B_TRUE); + abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd)); + abd_copy_from_buf(ub_abd, ub, sizeof (uberblock_t)); + + for (int l = 0; l < VDEV_LABELS; l++) + vdev_label_write(zio, vd, l, ub_abd, + VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd), + vdev_uberblock_sync_done, good_writes, + flags | ZIO_FLAG_DONT_PROPAGATE); + + abd_free(ub_abd); +} + +/* Sync the uberblocks to all vdevs in svd[] */ +static int +vdev_uberblock_sync_list(vdev_t **svd, int svdcount, uberblock_t *ub, int flags) +{ + spa_t *spa = svd[0]->vdev_spa; + zio_t *zio; + uint64_t good_writes = 0; + + zio = zio_root(spa, NULL, NULL, flags); + + for (int v = 0; v < svdcount; v++) + vdev_uberblock_sync(zio, &good_writes, ub, svd[v], flags); + + (void) zio_wait(zio); + + /* + * Flush the uberblocks to disk. This ensures that the odd labels + * are no longer needed (because the new uberblocks and the even + * labels are safely on disk), so it is safe to overwrite them. + */ + zio = zio_root(spa, NULL, NULL, flags); + + for (int v = 0; v < svdcount; v++) { + if (vdev_writeable(svd[v])) { + zio_flush(zio, svd[v]); + } + } + + (void) zio_wait(zio); + + return (good_writes >= 1 ? 0 : EIO); +} + +/* + * On success, increment the count of good writes for our top-level vdev. + */ +static void +vdev_label_sync_done(zio_t *zio) +{ + uint64_t *good_writes = zio->io_private; + + if (zio->io_error == 0) + atomic_inc_64(good_writes); +} + +/* + * If there weren't enough good writes, indicate failure to the parent. + */ +static void +vdev_label_sync_top_done(zio_t *zio) +{ + uint64_t *good_writes = zio->io_private; + + if (*good_writes == 0) + zio->io_error = SET_ERROR(EIO); + + kmem_free(good_writes, sizeof (uint64_t)); +} + +/* + * We ignore errors for log and cache devices, simply free the private data. + */ +static void +vdev_label_sync_ignore_done(zio_t *zio) +{ + kmem_free(zio->io_private, sizeof (uint64_t)); +} + +/* + * Write all even or odd labels to all leaves of the specified vdev. + */ +static void +vdev_label_sync(zio_t *zio, uint64_t *good_writes, + vdev_t *vd, int l, uint64_t txg, int flags) +{ + nvlist_t *label; + vdev_phys_t *vp; + abd_t *vp_abd; + char *buf; + size_t buflen; + + for (int c = 0; c < vd->vdev_children; c++) { + vdev_label_sync(zio, good_writes, + vd->vdev_child[c], l, txg, flags); + } + + if (!vd->vdev_ops->vdev_op_leaf) + return; + + if (!vdev_writeable(vd)) + return; + + /* + * Generate a label describing the top-level config to which we belong. + */ + label = spa_config_generate(vd->vdev_spa, vd, txg, B_FALSE); + + vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); + abd_zero(vp_abd, sizeof (vdev_phys_t)); + vp = abd_to_buf(vp_abd); + + buf = vp->vp_nvlist; + buflen = sizeof (vp->vp_nvlist); + + if (!nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP)) { + for (; l < VDEV_LABELS; l += 2) { + vdev_label_write(zio, vd, l, vp_abd, + offsetof(vdev_label_t, vl_vdev_phys), + sizeof (vdev_phys_t), + vdev_label_sync_done, good_writes, + flags | ZIO_FLAG_DONT_PROPAGATE); + } + } + + abd_free(vp_abd); + nvlist_free(label); +} + +static int +vdev_label_sync_list(spa_t *spa, int l, uint64_t txg, int flags) +{ + list_t *dl = &spa->spa_config_dirty_list; + vdev_t *vd; + zio_t *zio; + int error; + + /* + * Write the new labels to disk. + */ + zio = zio_root(spa, NULL, NULL, flags); + + for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) { + uint64_t *good_writes; + + ASSERT(!vd->vdev_ishole); + + good_writes = kmem_zalloc(sizeof (uint64_t), KM_SLEEP); + zio_t *vio = zio_null(zio, spa, NULL, + (vd->vdev_islog || vd->vdev_aux != NULL) ? + vdev_label_sync_ignore_done : vdev_label_sync_top_done, + good_writes, flags); + vdev_label_sync(vio, good_writes, vd, l, txg, flags); + zio_nowait(vio); + } + + error = zio_wait(zio); + + /* + * Flush the new labels to disk. + */ + zio = zio_root(spa, NULL, NULL, flags); + + for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) + zio_flush(zio, vd); + + (void) zio_wait(zio); + + return (error); +} + +/* + * Sync the uberblock and any changes to the vdev configuration. + * + * The order of operations is carefully crafted to ensure that + * if the system panics or loses power at any time, the state on disk + * is still transactionally consistent. The in-line comments below + * describe the failure semantics at each stage. + * + * Moreover, vdev_config_sync() is designed to be idempotent: if it fails + * at any time, you can just call it again, and it will resume its work. + */ +int +vdev_config_sync(vdev_t **svd, int svdcount, uint64_t txg) +{ + spa_t *spa = svd[0]->vdev_spa; + uberblock_t *ub = &spa->spa_uberblock; + int error = 0; + int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; + + ASSERT(svdcount != 0); +retry: + /* + * Normally, we don't want to try too hard to write every label and + * uberblock. If there is a flaky disk, we don't want the rest of the + * sync process to block while we retry. But if we can't write a + * single label out, we should retry with ZIO_FLAG_TRYHARD before + * bailing out and declaring the pool faulted. + */ + if (error != 0) { + if ((flags & ZIO_FLAG_TRYHARD) != 0) + return (error); + flags |= ZIO_FLAG_TRYHARD; + } + + ASSERT(ub->ub_txg <= txg); + + /* + * If this isn't a resync due to I/O errors, + * and nothing changed in this transaction group, + * and the vdev configuration hasn't changed, + * then there's nothing to do. + */ + if (ub->ub_txg < txg) { + boolean_t changed = uberblock_update(ub, spa->spa_root_vdev, + txg, spa->spa_mmp.mmp_delay); + + if (!changed && list_is_empty(&spa->spa_config_dirty_list)) + return (0); + } + + if (txg > spa_freeze_txg(spa)) + return (0); + + ASSERT(txg <= spa->spa_final_txg); + + /* + * Flush the write cache of every disk that's been written to + * in this transaction group. This ensures that all blocks + * written in this txg will be committed to stable storage + * before any uberblock that references them. + */ + zio_t *zio = zio_root(spa, NULL, NULL, flags); + + for (vdev_t *vd = + txg_list_head(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)); vd != NULL; + vd = txg_list_next(&spa->spa_vdev_txg_list, vd, TXG_CLEAN(txg))) + zio_flush(zio, vd); + + (void) zio_wait(zio); + + /* + * Sync out the even labels (L0, L2) for every dirty vdev. If the + * system dies in the middle of this process, that's OK: all of the + * even labels that made it to disk will be newer than any uberblock, + * and will therefore be considered invalid. The odd labels (L1, L3), + * which have not yet been touched, will still be valid. We flush + * the new labels to disk to ensure that all even-label updates + * are committed to stable storage before the uberblock update. + */ + if ((error = vdev_label_sync_list(spa, 0, txg, flags)) != 0) { + if ((flags & ZIO_FLAG_TRYHARD) != 0) { + zfs_dbgmsg("vdev_label_sync_list() returned error %d " + "for pool '%s' when syncing out the even labels " + "of dirty vdevs", error, spa_name(spa)); + } + goto retry; + } + + /* + * Sync the uberblocks to all vdevs in svd[]. + * If the system dies in the middle of this step, there are two cases + * to consider, and the on-disk state is consistent either way: + * + * (1) If none of the new uberblocks made it to disk, then the + * previous uberblock will be the newest, and the odd labels + * (which had not yet been touched) will be valid with respect + * to that uberblock. + * + * (2) If one or more new uberblocks made it to disk, then they + * will be the newest, and the even labels (which had all + * been successfully committed) will be valid with respect + * to the new uberblocks. + */ + if ((error = vdev_uberblock_sync_list(svd, svdcount, ub, flags)) != 0) { + if ((flags & ZIO_FLAG_TRYHARD) != 0) { + zfs_dbgmsg("vdev_uberblock_sync_list() returned error " + "%d for pool '%s'", error, spa_name(spa)); + } + goto retry; + } + + if (spa_multihost(spa)) + mmp_update_uberblock(spa, ub); + + /* + * Sync out odd labels for every dirty vdev. If the system dies + * in the middle of this process, the even labels and the new + * uberblocks will suffice to open the pool. The next time + * the pool is opened, the first thing we'll do -- before any + * user data is modified -- is mark every vdev dirty so that + * all labels will be brought up to date. We flush the new labels + * to disk to ensure that all odd-label updates are committed to + * stable storage before the next transaction group begins. + */ + if ((error = vdev_label_sync_list(spa, 1, txg, flags)) != 0) { + if ((flags & ZIO_FLAG_TRYHARD) != 0) { + zfs_dbgmsg("vdev_label_sync_list() returned error %d " + "for pool '%s' when syncing out the odd labels of " + "dirty vdevs", error, spa_name(spa)); + } + goto retry; + } + + return (0); +} |