diff options
Diffstat (limited to 'cmd/zhack/zhack.c')
| -rw-r--r-- | cmd/zhack/zhack.c | 533 |
1 files changed, 533 insertions, 0 deletions
diff --git a/cmd/zhack/zhack.c b/cmd/zhack/zhack.c new file mode 100644 index 000000000..b2cf815ca --- /dev/null +++ b/cmd/zhack/zhack.c @@ -0,0 +1,533 @@ +/* + * 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) 2012 by Delphix. All rights reserved. + */ + +/* + * zhack is a debugging tool that can write changes to ZFS pool using libzpool + * for testing purposes. Altering pools with zhack is unsupported and may + * result in corrupted pools. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <ctype.h> +#include <sys/zfs_context.h> +#include <sys/spa.h> +#include <sys/spa_impl.h> +#include <sys/dmu.h> +#include <sys/zap.h> +#include <sys/zfs_znode.h> +#include <sys/dsl_synctask.h> +#include <sys/vdev.h> +#include <sys/fs/zfs.h> +#include <sys/dmu_objset.h> +#include <sys/dsl_pool.h> +#include <sys/zio_checksum.h> +#include <sys/zio_compress.h> +#include <sys/zfeature.h> +#undef ZFS_MAXNAMELEN +#include <libzfs.h> + +extern boolean_t zfeature_checks_disable; + +const char cmdname[] = "zhack"; +libzfs_handle_t *g_zfs; +static importargs_t g_importargs; +static char *g_pool; +static boolean_t g_readonly; + +static void +usage(void) +{ + (void) fprintf(stderr, + "Usage: %s [-c cachefile] [-d dir] <subcommand> <args> ...\n" + "where <subcommand> <args> is one of the following:\n" + "\n", cmdname); + + (void) fprintf(stderr, + " feature stat <pool>\n" + " print information about enabled features\n" + " feature enable [-d desc] <pool> <feature>\n" + " add a new enabled feature to the pool\n" + " -d <desc> sets the feature's description\n" + " feature ref [-md] <pool> <feature>\n" + " change the refcount on the given feature\n" + " -d decrease instead of increase the refcount\n" + " -m add the feature to the label if increasing refcount\n" + "\n" + " <feature> : should be a feature guid\n"); + exit(1); +} + + +static void +fatal(const char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + (void) fprintf(stderr, "%s: ", cmdname); + (void) vfprintf(stderr, fmt, ap); + va_end(ap); + (void) fprintf(stderr, "\n"); + + exit(1); +} + +/* ARGSUSED */ +static int +space_delta_cb(dmu_object_type_t bonustype, void *data, + uint64_t *userp, uint64_t *groupp) +{ + /* + * Is it a valid type of object to track? + */ + if (bonustype != DMU_OT_ZNODE && bonustype != DMU_OT_SA) + return (ENOENT); + (void) fprintf(stderr, "modifying object that needs user accounting"); + abort(); + /* NOTREACHED */ +} + +/* + * Target is the dataset whose pool we want to open. + */ +static void +import_pool(const char *target, boolean_t readonly) +{ + nvlist_t *config; + nvlist_t *pools; + int error; + char *sepp; + spa_t *spa; + nvpair_t *elem; + nvlist_t *props; + const char *name; + + kernel_init(readonly ? FREAD : (FREAD | FWRITE)); + g_zfs = libzfs_init(); + ASSERT(g_zfs != NULL); + + dmu_objset_register_type(DMU_OST_ZFS, space_delta_cb); + + g_readonly = readonly; + + /* + * If we only want readonly access, it's OK if we find + * a potentially-active (ie, imported into the kernel) pool from the + * default cachefile. + */ + if (readonly && spa_open(target, &spa, FTAG) == 0) { + spa_close(spa, FTAG); + return; + } + + g_importargs.unique = B_TRUE; + g_importargs.can_be_active = readonly; + g_pool = strdup(target); + if ((sepp = strpbrk(g_pool, "/@")) != NULL) + *sepp = '\0'; + g_importargs.poolname = g_pool; + pools = zpool_search_import(g_zfs, &g_importargs); + + if (pools == NULL || nvlist_next_nvpair(pools, NULL) == NULL) { + if (!g_importargs.can_be_active) { + g_importargs.can_be_active = B_TRUE; + if (zpool_search_import(g_zfs, &g_importargs) != NULL || + spa_open(target, &spa, FTAG) == 0) { + fatal("cannot import '%s': pool is active; run " + "\"zpool export %s\" first\n", + g_pool, g_pool); + } + } + + fatal("cannot import '%s': no such pool available\n", g_pool); + } + + elem = nvlist_next_nvpair(pools, NULL); + name = nvpair_name(elem); + VERIFY(nvpair_value_nvlist(elem, &config) == 0); + + props = NULL; + if (readonly) { + VERIFY(nvlist_alloc(&props, NV_UNIQUE_NAME, 0) == 0); + VERIFY(nvlist_add_uint64(props, + zpool_prop_to_name(ZPOOL_PROP_READONLY), 1) == 0); + } + + zfeature_checks_disable = B_TRUE; + error = spa_import(name, config, props, ZFS_IMPORT_NORMAL); + zfeature_checks_disable = B_FALSE; + if (error == EEXIST) + error = 0; + + if (error) + fatal("can't import '%s': %s", name, strerror(error)); +} + +static void +zhack_spa_open(const char *target, boolean_t readonly, void *tag, spa_t **spa) +{ + int err; + + import_pool(target, readonly); + + zfeature_checks_disable = B_TRUE; + err = spa_open(target, spa, tag); + zfeature_checks_disable = B_FALSE; + + if (err != 0) + fatal("cannot open '%s': %s", target, strerror(err)); + if (spa_version(*spa) < SPA_VERSION_FEATURES) { + fatal("'%s' has version %d, features not enabled", target, + (int)spa_version(*spa)); + } +} + +static void +dump_obj(objset_t *os, uint64_t obj, const char *name) +{ + zap_cursor_t zc; + zap_attribute_t za; + + (void) printf("%s_obj:\n", name); + + for (zap_cursor_init(&zc, os, obj); + zap_cursor_retrieve(&zc, &za) == 0; + zap_cursor_advance(&zc)) { + if (za.za_integer_length == 8) { + ASSERT(za.za_num_integers == 1); + (void) printf("\t%s = %llu\n", + za.za_name, (u_longlong_t)za.za_first_integer); + } else { + ASSERT(za.za_integer_length == 1); + char val[1024]; + VERIFY(zap_lookup(os, obj, za.za_name, + 1, sizeof (val), val) == 0); + (void) printf("\t%s = %s\n", za.za_name, val); + } + } + zap_cursor_fini(&zc); +} + +static void +dump_mos(spa_t *spa) +{ + nvlist_t *nv = spa->spa_label_features; + nvpair_t *pair; + + (void) printf("label config:\n"); + for (pair = nvlist_next_nvpair(nv, NULL); + pair != NULL; + pair = nvlist_next_nvpair(nv, pair)) { + (void) printf("\t%s\n", nvpair_name(pair)); + } +} + +static void +zhack_do_feature_stat(int argc, char **argv) +{ + spa_t *spa; + objset_t *os; + char *target; + + argc--; + argv++; + + if (argc < 1) { + (void) fprintf(stderr, "error: missing pool name\n"); + usage(); + } + target = argv[0]; + + zhack_spa_open(target, B_TRUE, FTAG, &spa); + os = spa->spa_meta_objset; + + dump_obj(os, spa->spa_feat_for_read_obj, "for_read"); + dump_obj(os, spa->spa_feat_for_write_obj, "for_write"); + dump_obj(os, spa->spa_feat_desc_obj, "descriptions"); + dump_mos(spa); + + spa_close(spa, FTAG); +} + +static void +feature_enable_sync(void *arg1, void *arg2, dmu_tx_t *tx) +{ + spa_t *spa = arg1; + zfeature_info_t *feature = arg2; + + spa_feature_enable(spa, feature, tx); +} + +static void +zhack_do_feature_enable(int argc, char **argv) +{ + char c; + char *desc, *target; + spa_t *spa; + objset_t *mos; + zfeature_info_t feature; + zfeature_info_t *nodeps[] = { NULL }; + + /* + * Features are not added to the pool's label until their refcounts + * are incremented, so fi_mos can just be left as false for now. + */ + desc = NULL; + feature.fi_uname = "zhack"; + feature.fi_mos = B_FALSE; + feature.fi_can_readonly = B_FALSE; + feature.fi_depends = nodeps; + + optind = 1; + while ((c = getopt(argc, argv, "rmd:")) != -1) { + switch (c) { + case 'r': + feature.fi_can_readonly = B_TRUE; + break; + case 'd': + desc = strdup(optarg); + break; + default: + usage(); + break; + } + } + + if (desc == NULL) + desc = strdup("zhack injected"); + feature.fi_desc = desc; + + argc -= optind; + argv += optind; + + if (argc < 2) { + (void) fprintf(stderr, "error: missing feature or pool name\n"); + usage(); + } + target = argv[0]; + feature.fi_guid = argv[1]; + + if (!zfeature_is_valid_guid(feature.fi_guid)) + fatal("invalid feature guid: %s", feature.fi_guid); + + zhack_spa_open(target, B_FALSE, FTAG, &spa); + mos = spa->spa_meta_objset; + + if (0 == zfeature_lookup_guid(feature.fi_guid, NULL)) + fatal("'%s' is a real feature, will not enable"); + if (0 == zap_contains(mos, spa->spa_feat_desc_obj, feature.fi_guid)) + fatal("feature already enabled: %s", feature.fi_guid); + + VERIFY3U(0, ==, dsl_sync_task_do(spa->spa_dsl_pool, NULL, + feature_enable_sync, spa, &feature, 5)); + + spa_close(spa, FTAG); + + free(desc); +} + +static void +feature_incr_sync(void *arg1, void *arg2, dmu_tx_t *tx) +{ + spa_t *spa = arg1; + zfeature_info_t *feature = arg2; + + spa_feature_incr(spa, feature, tx); +} + +static void +feature_decr_sync(void *arg1, void *arg2, dmu_tx_t *tx) +{ + spa_t *spa = arg1; + zfeature_info_t *feature = arg2; + + spa_feature_decr(spa, feature, tx); +} + +static void +zhack_do_feature_ref(int argc, char **argv) +{ + char c; + char *target; + boolean_t decr = B_FALSE; + spa_t *spa; + objset_t *mos; + zfeature_info_t feature; + zfeature_info_t *nodeps[] = { NULL }; + + /* + * fi_desc does not matter here because it was written to disk + * when the feature was enabled, but we need to properly set the + * feature for read or write based on the information we read off + * disk later. + */ + feature.fi_uname = "zhack"; + feature.fi_mos = B_FALSE; + feature.fi_desc = NULL; + feature.fi_depends = nodeps; + + optind = 1; + while ((c = getopt(argc, argv, "md")) != -1) { + switch (c) { + case 'm': + feature.fi_mos = B_TRUE; + break; + case 'd': + decr = B_TRUE; + break; + default: + usage(); + break; + } + } + argc -= optind; + argv += optind; + + if (argc < 2) { + (void) fprintf(stderr, "error: missing feature or pool name\n"); + usage(); + } + target = argv[0]; + feature.fi_guid = argv[1]; + + if (!zfeature_is_valid_guid(feature.fi_guid)) + fatal("invalid feature guid: %s", feature.fi_guid); + + zhack_spa_open(target, B_FALSE, FTAG, &spa); + mos = spa->spa_meta_objset; + + if (0 == zfeature_lookup_guid(feature.fi_guid, NULL)) + fatal("'%s' is a real feature, will not change refcount"); + + if (0 == zap_contains(mos, spa->spa_feat_for_read_obj, + feature.fi_guid)) { + feature.fi_can_readonly = B_FALSE; + } else if (0 == zap_contains(mos, spa->spa_feat_for_write_obj, + feature.fi_guid)) { + feature.fi_can_readonly = B_TRUE; + } else { + fatal("feature is not enabled: %s", feature.fi_guid); + } + + if (decr && !spa_feature_is_active(spa, &feature)) + fatal("feature refcount already 0: %s", feature.fi_guid); + + VERIFY3U(0, ==, dsl_sync_task_do(spa->spa_dsl_pool, NULL, + decr ? feature_decr_sync : feature_incr_sync, spa, &feature, 5)); + + spa_close(spa, FTAG); +} + +static int +zhack_do_feature(int argc, char **argv) +{ + char *subcommand; + + argc--; + argv++; + if (argc == 0) { + (void) fprintf(stderr, + "error: no feature operation specified\n"); + usage(); + } + + subcommand = argv[0]; + if (strcmp(subcommand, "stat") == 0) { + zhack_do_feature_stat(argc, argv); + } else if (strcmp(subcommand, "enable") == 0) { + zhack_do_feature_enable(argc, argv); + } else if (strcmp(subcommand, "ref") == 0) { + zhack_do_feature_ref(argc, argv); + } else { + (void) fprintf(stderr, "error: unknown subcommand: %s\n", + subcommand); + usage(); + } + + return (0); +} + +#define MAX_NUM_PATHS 1024 + +int +main(int argc, char **argv) +{ + extern void zfs_prop_init(void); + + char *path[MAX_NUM_PATHS]; + const char *subcommand; + int rv = 0; + char c; + + g_importargs.path = path; + + dprintf_setup(&argc, argv); + zfs_prop_init(); + + while ((c = getopt(argc, argv, "c:d:")) != -1) { + switch (c) { + case 'c': + g_importargs.cachefile = optarg; + break; + case 'd': + assert(g_importargs.paths < MAX_NUM_PATHS); + g_importargs.path[g_importargs.paths++] = optarg; + break; + default: + usage(); + break; + } + } + + argc -= optind; + argv += optind; + optind = 1; + + if (argc == 0) { + (void) fprintf(stderr, "error: no command specified\n"); + usage(); + } + + subcommand = argv[0]; + + if (strcmp(subcommand, "feature") == 0) { + rv = zhack_do_feature(argc, argv); + } else { + (void) fprintf(stderr, "error: unknown subcommand: %s\n", + subcommand); + usage(); + } + + if (!g_readonly && spa_export(g_pool, NULL, B_TRUE, B_TRUE) != 0) { + fatal("pool export failed; " + "changes may not be committed to disk\n"); + } + + libzfs_fini(g_zfs); + kernel_fini(); + + return (rv); +} |