diff options
Diffstat (limited to 'sys/contrib/openzfs/lib/libzfs/libzfs_config.c')
-rw-r--r-- | sys/contrib/openzfs/lib/libzfs/libzfs_config.c | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/sys/contrib/openzfs/lib/libzfs/libzfs_config.c b/sys/contrib/openzfs/lib/libzfs/libzfs_config.c new file mode 100644 index 000000000000..a3ecc4a327dc --- /dev/null +++ b/sys/contrib/openzfs/lib/libzfs/libzfs_config.c @@ -0,0 +1,457 @@ +/* + * 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 2009 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +/* + * Copyright (c) 2012 by Delphix. All rights reserved. + * Copyright (c) 2015 by Syneto S.R.L. All rights reserved. + * Copyright 2016 Nexenta Systems, Inc. + */ + +/* + * The pool configuration repository is stored in /etc/zfs/zpool.cache as a + * single packed nvlist. While it would be nice to just read in this + * file from userland, this wouldn't work from a local zone. So we have to have + * a zpool ioctl to return the complete configuration for all pools. In the + * global zone, this will be identical to reading the file and unpacking it in + * userland. + */ + +#include <errno.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <stddef.h> +#include <string.h> +#include <unistd.h> +#include <libintl.h> +#include <libuutil.h> + +#include "libzfs_impl.h" + +typedef struct config_node { + char *cn_name; + nvlist_t *cn_config; + uu_avl_node_t cn_avl; +} config_node_t; + +/* ARGSUSED */ +static int +config_node_compare(const void *a, const void *b, void *unused) +{ + int ret; + + const config_node_t *ca = (config_node_t *)a; + const config_node_t *cb = (config_node_t *)b; + + ret = strcmp(ca->cn_name, cb->cn_name); + + if (ret < 0) + return (-1); + else if (ret > 0) + return (1); + else + return (0); +} + +void +namespace_clear(libzfs_handle_t *hdl) +{ + if (hdl->libzfs_ns_avl) { + config_node_t *cn; + void *cookie = NULL; + + while ((cn = uu_avl_teardown(hdl->libzfs_ns_avl, + &cookie)) != NULL) { + nvlist_free(cn->cn_config); + free(cn->cn_name); + free(cn); + } + + uu_avl_destroy(hdl->libzfs_ns_avl); + hdl->libzfs_ns_avl = NULL; + } + + if (hdl->libzfs_ns_avlpool) { + uu_avl_pool_destroy(hdl->libzfs_ns_avlpool); + hdl->libzfs_ns_avlpool = NULL; + } +} + +/* + * Loads the pool namespace, or re-loads it if the cache has changed. + */ +static int +namespace_reload(libzfs_handle_t *hdl) +{ + nvlist_t *config; + config_node_t *cn; + nvpair_t *elem; + zfs_cmd_t zc = {"\0"}; + void *cookie; + + if (hdl->libzfs_ns_gen == 0) { + /* + * This is the first time we've accessed the configuration + * cache. Initialize the AVL tree and then fall through to the + * common code. + */ + if ((hdl->libzfs_ns_avlpool = uu_avl_pool_create("config_pool", + sizeof (config_node_t), + offsetof(config_node_t, cn_avl), + config_node_compare, UU_DEFAULT)) == NULL) + return (no_memory(hdl)); + + if ((hdl->libzfs_ns_avl = uu_avl_create(hdl->libzfs_ns_avlpool, + NULL, UU_DEFAULT)) == NULL) + return (no_memory(hdl)); + } + + if (zcmd_alloc_dst_nvlist(hdl, &zc, 0) != 0) + return (-1); + + for (;;) { + zc.zc_cookie = hdl->libzfs_ns_gen; + if (zfs_ioctl(hdl, ZFS_IOC_POOL_CONFIGS, &zc) != 0) { + switch (errno) { + case EEXIST: + /* + * The namespace hasn't changed. + */ + zcmd_free_nvlists(&zc); + return (0); + + case ENOMEM: + if (zcmd_expand_dst_nvlist(hdl, &zc) != 0) { + zcmd_free_nvlists(&zc); + return (-1); + } + break; + + default: + zcmd_free_nvlists(&zc); + return (zfs_standard_error(hdl, errno, + dgettext(TEXT_DOMAIN, "failed to read " + "pool configuration"))); + } + } else { + hdl->libzfs_ns_gen = zc.zc_cookie; + break; + } + } + + if (zcmd_read_dst_nvlist(hdl, &zc, &config) != 0) { + zcmd_free_nvlists(&zc); + return (-1); + } + + zcmd_free_nvlists(&zc); + + /* + * Clear out any existing configuration information. + */ + cookie = NULL; + while ((cn = uu_avl_teardown(hdl->libzfs_ns_avl, &cookie)) != NULL) { + nvlist_free(cn->cn_config); + free(cn->cn_name); + free(cn); + } + + elem = NULL; + while ((elem = nvlist_next_nvpair(config, elem)) != NULL) { + nvlist_t *child; + uu_avl_index_t where; + + if ((cn = zfs_alloc(hdl, sizeof (config_node_t))) == NULL) { + nvlist_free(config); + return (-1); + } + + if ((cn->cn_name = zfs_strdup(hdl, + nvpair_name(elem))) == NULL) { + free(cn); + nvlist_free(config); + return (-1); + } + + verify(nvpair_value_nvlist(elem, &child) == 0); + if (nvlist_dup(child, &cn->cn_config, 0) != 0) { + free(cn->cn_name); + free(cn); + nvlist_free(config); + return (no_memory(hdl)); + } + verify(uu_avl_find(hdl->libzfs_ns_avl, cn, NULL, &where) + == NULL); + + uu_avl_insert(hdl->libzfs_ns_avl, cn, where); + } + + nvlist_free(config); + return (0); +} + +/* + * Retrieve the configuration for the given pool. The configuration is an nvlist + * describing the vdevs, as well as the statistics associated with each one. + */ +nvlist_t * +zpool_get_config(zpool_handle_t *zhp, nvlist_t **oldconfig) +{ + if (oldconfig) + *oldconfig = zhp->zpool_old_config; + return (zhp->zpool_config); +} + +/* + * Retrieves a list of enabled features and their refcounts and caches it in + * the pool handle. + */ +nvlist_t * +zpool_get_features(zpool_handle_t *zhp) +{ + nvlist_t *config, *features; + + config = zpool_get_config(zhp, NULL); + + if (config == NULL || !nvlist_exists(config, + ZPOOL_CONFIG_FEATURE_STATS)) { + int error; + boolean_t missing = B_FALSE; + + error = zpool_refresh_stats(zhp, &missing); + + if (error != 0 || missing) + return (NULL); + + config = zpool_get_config(zhp, NULL); + } + + if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_FEATURE_STATS, + &features) != 0) + return (NULL); + + return (features); +} + +/* + * Refresh the vdev statistics associated with the given pool. This is used in + * iostat to show configuration changes and determine the delta from the last + * time the function was called. This function can fail, in case the pool has + * been destroyed. + */ +int +zpool_refresh_stats(zpool_handle_t *zhp, boolean_t *missing) +{ + zfs_cmd_t zc = {"\0"}; + int error; + nvlist_t *config; + libzfs_handle_t *hdl = zhp->zpool_hdl; + + *missing = B_FALSE; + (void) strcpy(zc.zc_name, zhp->zpool_name); + + if (zhp->zpool_config_size == 0) + zhp->zpool_config_size = 1 << 16; + + if (zcmd_alloc_dst_nvlist(hdl, &zc, zhp->zpool_config_size) != 0) + return (-1); + + for (;;) { + if (zfs_ioctl(zhp->zpool_hdl, ZFS_IOC_POOL_STATS, + &zc) == 0) { + /* + * The real error is returned in the zc_cookie field. + */ + error = zc.zc_cookie; + break; + } + + if (errno == ENOMEM) { + if (zcmd_expand_dst_nvlist(hdl, &zc) != 0) { + zcmd_free_nvlists(&zc); + return (-1); + } + } else { + zcmd_free_nvlists(&zc); + if (errno == ENOENT || errno == EINVAL) + *missing = B_TRUE; + zhp->zpool_state = POOL_STATE_UNAVAIL; + return (0); + } + } + + if (zcmd_read_dst_nvlist(hdl, &zc, &config) != 0) { + zcmd_free_nvlists(&zc); + return (-1); + } + + zcmd_free_nvlists(&zc); + + zhp->zpool_config_size = zc.zc_nvlist_dst_size; + + if (zhp->zpool_config != NULL) { + nvlist_free(zhp->zpool_old_config); + + zhp->zpool_old_config = zhp->zpool_config; + } + + zhp->zpool_config = config; + if (error) + zhp->zpool_state = POOL_STATE_UNAVAIL; + else + zhp->zpool_state = POOL_STATE_ACTIVE; + + return (0); +} + +/* + * The following environment variables are undocumented + * and should be used for testing purposes only: + * + * __ZFS_POOL_EXCLUDE - don't iterate over the pools it lists + * __ZFS_POOL_RESTRICT - iterate only over the pools it lists + * + * This function returns B_TRUE if the pool should be skipped + * during iteration. + */ +boolean_t +zpool_skip_pool(const char *poolname) +{ + static boolean_t initialized = B_FALSE; + static const char *exclude = NULL; + static const char *restricted = NULL; + + const char *cur, *end; + int len; + int namelen = strlen(poolname); + + if (!initialized) { + initialized = B_TRUE; + exclude = getenv("__ZFS_POOL_EXCLUDE"); + restricted = getenv("__ZFS_POOL_RESTRICT"); + } + + if (exclude != NULL) { + cur = exclude; + do { + end = strchr(cur, ' '); + len = (NULL == end) ? strlen(cur) : (end - cur); + if (len == namelen && 0 == strncmp(cur, poolname, len)) + return (B_TRUE); + cur += (len + 1); + } while (NULL != end); + } + + if (NULL == restricted) + return (B_FALSE); + + cur = restricted; + do { + end = strchr(cur, ' '); + len = (NULL == end) ? strlen(cur) : (end - cur); + + if (len == namelen && 0 == strncmp(cur, poolname, len)) { + return (B_FALSE); + } + + cur += (len + 1); + } while (NULL != end); + + return (B_TRUE); +} + +/* + * Iterate over all pools in the system. + */ +int +zpool_iter(libzfs_handle_t *hdl, zpool_iter_f func, void *data) +{ + config_node_t *cn; + zpool_handle_t *zhp; + int ret; + + /* + * If someone makes a recursive call to zpool_iter(), we want to avoid + * refreshing the namespace because that will invalidate the parent + * context. We allow recursive calls, but simply re-use the same + * namespace AVL tree. + */ + if (!hdl->libzfs_pool_iter && namespace_reload(hdl) != 0) + return (-1); + + hdl->libzfs_pool_iter++; + for (cn = uu_avl_first(hdl->libzfs_ns_avl); cn != NULL; + cn = uu_avl_next(hdl->libzfs_ns_avl, cn)) { + + if (zpool_skip_pool(cn->cn_name)) + continue; + + if (zpool_open_silent(hdl, cn->cn_name, &zhp) != 0) { + hdl->libzfs_pool_iter--; + return (-1); + } + + if (zhp == NULL) + continue; + + if ((ret = func(zhp, data)) != 0) { + hdl->libzfs_pool_iter--; + return (ret); + } + } + hdl->libzfs_pool_iter--; + + return (0); +} + +/* + * Iterate over root datasets, calling the given function for each. The zfs + * handle passed each time must be explicitly closed by the callback. + */ +int +zfs_iter_root(libzfs_handle_t *hdl, zfs_iter_f func, void *data) +{ + config_node_t *cn; + zfs_handle_t *zhp; + int ret; + + if (namespace_reload(hdl) != 0) + return (-1); + + for (cn = uu_avl_first(hdl->libzfs_ns_avl); cn != NULL; + cn = uu_avl_next(hdl->libzfs_ns_avl, cn)) { + + if (zpool_skip_pool(cn->cn_name)) + continue; + + if ((zhp = make_dataset_handle(hdl, cn->cn_name)) == NULL) + continue; + + if ((ret = func(zhp, data)) != 0) + return (ret); + } + + return (0); +} |