/* * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved. * Copyright (C) 2004-2012 Red Hat, Inc. All rights reserved. * * This file is part of LVM2. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU Lesser General Public License v.2.1. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "tools.h" #include "lvmetad.h" #include "lvmcache.h" struct pvscan_params { int new_pvs_found; int pvs_found; uint64_t size_total; uint64_t size_new; unsigned pv_max_name_len; unsigned vg_max_name_len; unsigned pv_tmp_namelen; char *pv_tmp_name; }; struct pvscan_aa_params { int refresh_all; unsigned int activate_errors; struct dm_list changed_vgnames; }; static int _pvscan_display_single(struct cmd_context *cmd, struct physical_volume *pv, struct pvscan_params *params) { /* XXXXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXXXX */ char uuid[40] __attribute__((aligned(8))); const unsigned suffix_len = sizeof(uuid) + 10; unsigned pv_len; const char *pvdevname = pv_dev_name(pv); /* short listing? */ if (arg_is_set(cmd, short_ARG)) { log_print_unless_silent("%s", pvdevname); return ECMD_PROCESSED; } if (!params->pv_max_name_len) { lvmcache_get_max_name_lengths(cmd, ¶ms->pv_max_name_len, ¶ms->vg_max_name_len); params->pv_max_name_len += 2; params->vg_max_name_len += 2; params->pv_tmp_namelen = params->pv_max_name_len + suffix_len; if (!(params->pv_tmp_name = dm_pool_alloc(cmd->mem, params->pv_tmp_namelen))) return ECMD_FAILED; } pv_len = params->pv_max_name_len; memset(params->pv_tmp_name, 0, params->pv_tmp_namelen); if (arg_is_set(cmd, uuid_ARG)) { if (!id_write_format(&pv->id, uuid, sizeof(uuid))) { stack; return ECMD_FAILED; } if (dm_snprintf(params->pv_tmp_name, params->pv_tmp_namelen, "%-*s with UUID %s", params->pv_max_name_len - 2, pvdevname, uuid) < 0) { log_error("Invalid PV name with uuid."); return ECMD_FAILED; } pvdevname = params->pv_tmp_name; pv_len += suffix_len; } if (is_orphan(pv)) log_print_unless_silent("PV %-*s %-*s %s [%s]", pv_len, pvdevname, params->vg_max_name_len, " ", pv->fmt ? pv->fmt->name : " ", display_size(cmd, pv_size(pv))); else if (pv_status(pv) & EXPORTED_VG) log_print_unless_silent("PV %-*s is in exported VG %s [%s / %s free]", pv_len, pvdevname, pv_vg_name(pv), display_size(cmd, (uint64_t) pv_pe_count(pv) * pv_pe_size(pv)), display_size(cmd, (uint64_t) (pv_pe_count(pv) - pv_pe_alloc_count(pv)) * pv_pe_size(pv))); else log_print_unless_silent("PV %-*s VG %-*s %s [%s / %s free]", pv_len, pvdevname, params->vg_max_name_len, pv_vg_name(pv), pv->fmt ? pv->fmt->name : " ", display_size(cmd, (uint64_t) pv_pe_count(pv) * pv_pe_size(pv)), display_size(cmd, (uint64_t) (pv_pe_count(pv) - pv_pe_alloc_count(pv)) * pv_pe_size(pv))); return ECMD_PROCESSED; } static int _pvscan_single(struct cmd_context *cmd, struct volume_group *vg, struct physical_volume *pv, struct processing_handle *handle) { struct pvscan_params *params = (struct pvscan_params *)handle->custom_handle; if ((arg_is_set(cmd, exported_ARG) && !(pv_status(pv) & EXPORTED_VG)) || (arg_is_set(cmd, novolumegroup_ARG) && (!is_orphan(pv)))) { return ECMD_PROCESSED; } params->pvs_found++; if (is_orphan(pv)) { params->new_pvs_found++; params->size_new += pv_size(pv); params->size_total += pv_size(pv); } else { params->size_total += (uint64_t) pv_pe_count(pv) * pv_pe_size(pv); } _pvscan_display_single(cmd, pv, params); return ECMD_PROCESSED; } static int _lvmetad_clear_dev(dev_t devno, int32_t major, int32_t minor) { char buf[24]; (void) dm_snprintf(buf, sizeof(buf), FMTi32 ":" FMTi32, major, minor); if (!lvmetad_pv_gone(devno, buf)) return_0; log_print_unless_silent("Device %s not found. Cleared from lvmetad cache.", buf); return 1; } /* * pvscan --cache does not perform any lvmlockd locking, and * pvscan --cache -aay skips autoactivation in lockd VGs. * * pvscan --cache populates lvmetad with VG metadata from disk. * No lvmlockd locking is needed. It is expected that lockd VG * metadata that is read by pvscan and populated in lvmetad may * be immediately stale due to changes to the VG from other hosts * during or after this pvscan. This is normal and not a problem. * When a subsequent lvm command uses the VG, it will lock the VG * with lvmlockd, read the VG from lvmetad, and update the cached * copy from disk if necessary. * * pvscan --cache -aay does not activate LVs in lockd VGs because * activation requires locking, and a lock-start operation is needed * on a lockd VG before any locking can be performed in it. * * An equivalent of pvscan --cache -aay for lockd VGs is: * 1. pvscan --cache * 2. vgchange --lock-start * 3. vgchange -aay -S 'locktype=sanlock || locktype=dlm' * * [We could eventually add support for autoactivating lockd VGs * using pvscan by incorporating the lock start step (which can * take a long time), but there may be a better option than * continuing to overload pvscan.] * * Stages of starting a lockd VG: * * . pvscan --cache populates lockd VGs in lvmetad without locks, * and this initial cached copy may quickly become stale. * * . vgchange --lock-start VG reads the VG without the VG lock * because no locks are available until the locking is started. * It only uses the VG name and lock_type from the VG metadata, * and then only uses it to start the VG lockspace in lvmlockd. * * . Further lvm commands, e.g. activation, can then lock the VG * with lvmlockd and use current VG metdata. */ #define REFRESH_BEFORE_AUTOACTIVATION_RETRIES 5 #define REFRESH_BEFORE_AUTOACTIVATION_RETRY_USLEEP_DELAY 100000 static int _pvscan_autoactivate_single(struct cmd_context *cmd, const char *vg_name, struct volume_group *vg, struct processing_handle *handle) { struct pvscan_aa_params *pp = (struct pvscan_aa_params *)handle->custom_handle; unsigned int refresh_retries = REFRESH_BEFORE_AUTOACTIVATION_RETRIES; int refresh_done = 0; if (vg_is_clustered(vg)) return ECMD_PROCESSED; if (vg_is_exported(vg)) return ECMD_PROCESSED; if (is_lockd_type(vg->lock_type)) return ECMD_PROCESSED; log_debug("pvscan autoactivating VG %s.", vg_name); /* * Refresh LVs in a VG that has "changed" from finding a PV. * The meaning of "changed" is determined in lvmetad, and is * returned to the command as a flag. * * FIXME: There's a tiny race when suspending the device which is part * of the refresh because when suspend ioctl is performed, the dm * kernel driver executes (do_suspend and dm_suspend kernel fn): * * step 1: a check whether the dev is already suspended and * if yes it returns success immediately as there's * nothing to do * step 2: it grabs the suspend lock * step 3: another check whether the dev is already suspended * and if found suspended, it exits with -EINVAL now * * The race can occur in between step 1 and step 2. To prevent premature * autoactivation failure, we're using a simple retry logic here before * we fail completely. For a complete solution, we need to fix the * locking so there's no possibility for suspend calls to interleave * each other to cause this kind of race. * * Remove this workaround with "refresh_retries" once we have proper locking in! */ if (pp->refresh_all || str_list_match_item(&pp->changed_vgnames, vg_name)) { while (refresh_retries--) { log_debug_activation("Refreshing VG %s before autoactivation.", vg_name); if (vg_refresh_visible(cmd, vg)) { refresh_done = 1; break; } usleep(REFRESH_BEFORE_AUTOACTIVATION_RETRY_USLEEP_DELAY); } if (!refresh_done) log_warn("%s: refresh before autoactivation failed.", vg->name); } log_debug_activation("Autoactivating VG %s.", vg_name); if (!vgchange_activate(cmd, vg, CHANGE_AAY)) { log_error("%s: autoactivation failed.", vg->name); pp->activate_errors++; goto out; } /* * After sucessfull activation we need to initialise polling * for all activated LVs in a VG. Possible enhancement would * be adding --poll y|n cmdline option for pvscan and call * init_background_polling routine in autoactivation handler. */ log_debug_activation("Starting background polling for VG %s.", vg_name); if (!(vgchange_background_polling(cmd, vg))) goto_out; out: return ECMD_PROCESSED; } static int _pvscan_autoactivate(struct cmd_context *cmd, struct pvscan_aa_params *pp, int all_vgs, struct dm_list *vgnames) { struct processing_handle *handle = NULL; int ret; if (!all_vgs && dm_list_empty(vgnames)) { log_debug("No VGs to autoactivate."); return ECMD_PROCESSED; } if (!lvmetad_used()) log_warn("WARNING: Autoactivation reading from disk instead of lvmetad."); if (!(handle = init_processing_handle(cmd, NULL))) { log_error("Failed to initialize processing handle."); return ECMD_FAILED; } handle->custom_handle = pp; if (all_vgs) { cmd->cname->flags |= ALL_VGS_IS_DEFAULT; pp->refresh_all = 1; } dev_cache_full_scan(cmd->full_filter); ret = process_each_vg(cmd, 0, NULL, NULL, vgnames, 0, 0, handle, _pvscan_autoactivate_single); destroy_processing_handle(cmd, handle); return ret; } static int _pvscan_cache(struct cmd_context *cmd, int argc, char **argv) { struct pvscan_aa_params pp = { 0 }; struct dm_list found_vgnames; struct device *dev; const char *pv_name; const char *reason = NULL; int32_t major = -1; int32_t minor = -1; int devno_args = 0; struct arg_value_group_list *current_group; dev_t devno; int do_activate; int all_vgs = 0; int remove_errors = 0; int add_errors = 0; int ret = ECMD_PROCESSED; dm_list_init(&found_vgnames); dm_list_init(&pp.changed_vgnames); do_activate = arg_is_set(cmd, activate_ARG); if (!lvmetad_used() && !do_activate) { log_verbose("Ignoring pvscan --cache because lvmetad is not in use."); return ret; } if (do_activate && (arg_uint_value(cmd, activate_ARG, CHANGE_AAY) != CHANGE_AAY)) { log_error("Only --activate ay allowed with pvscan."); return 0; } if (!lvmetad_used() && do_activate && !find_config_tree_bool(cmd, global_use_lvmetad_CFG, NULL)) { log_verbose("Ignoring pvscan --cache -aay because lvmetad is not in use."); return ret; } if (arg_is_set(cmd, major_ARG) + arg_is_set(cmd, minor_ARG)) devno_args = 1; if (devno_args && (!arg_is_set(cmd, major_ARG) || !arg_is_set(cmd, minor_ARG))) { log_error("Both --major and --minor required to identify devices."); return EINVALID_CMD_LINE; } if (!lock_vol(cmd, VG_GLOBAL, LCK_VG_READ, NULL)) { log_error("Unable to obtain global lock."); return ECMD_FAILED; } /* * This a special case where use_lvmetad=1 in lvm.conf but pvscan * cannot use lvmetad for some reason. In this case pvscan should * still activate LVs even though it's not updating the cache. */ if (do_activate && !lvmetad_used()) { log_verbose("Activating all VGs without lvmetad."); all_vgs = 1; devno_args = 0; goto activate; } /* * Scan all devices when no args are given. */ if (!argc && !devno_args) { log_verbose("Scanning all devices."); if (!lvmetad_pvscan_all_devs(cmd, 1)) { log_warn("WARNING: Not using lvmetad because cache update failed."); lvmetad_make_unused(cmd); } if (lvmetad_used() && lvmetad_is_disabled(cmd, &reason)) { log_warn("WARNING: Not using lvmetad because %s.", reason); lvmetad_make_unused(cmd); } all_vgs = 1; goto activate; } /* * FIXME: when specific devs are named, we generally don't want to scan * any other devs, but if lvmetad is not yet populated, the first * 'pvscan --cache dev' does need to do a full scan. We want to remove * the need for this case so that 'pvscan --cache dev' is guaranteed to * never scan any devices other than those specified. */ if (!lvmetad_token_matches(cmd)) { log_verbose("Scanning all devices to initialize lvmetad."); if (lvmetad_used() && !lvmetad_pvscan_all_devs(cmd, 0)) { log_warn("WARNING: Not using lvmetad because cache update failed."); lvmetad_make_unused(cmd); } if (lvmetad_used() && lvmetad_is_disabled(cmd, &reason)) { log_warn("WARNING: Not using lvmetad because %s.", reason); lvmetad_make_unused(cmd); } all_vgs = 1; goto activate; } /* * When args are given, scan only those devices. If lvmetad is already * disabled, a full scan is required to reenable it, so there's no * point in doing individual device scans, so go directly to * autoactivation. (FIXME: Should we also skip autoactivation in this * case since that will read disks with lvmetad disabled? * i.e. avoid disk access and not activate LVs, or or read from disk * and activate LVs?) */ if (lvmetad_is_disabled(cmd, &reason)) { log_warn("WARNING: Not using lvmetad because %s.", reason); lvmetad_make_unused(cmd); all_vgs = 1; goto activate; } /* * Step 1: for each device, if it's no longer found, then tell lvmetad * to drop it. If the device exists, read metadata from it and send * that to lvmetad. * * When given a device name, check if the device is not visible to * lvmetad, but still visible to the system, and if so, tell lvmetad to * drop it (using the major:minor from the system). * * When given a major:minor which is not visible to the system, just * tell lvmetad to drop it directly using that major:minor. * * When a device has left the system, it must be dropped using * --major/--minor because we cannot map the device name to major:minor * after the device has left. (A full rescan could of course be used * to drop any devices that have left.) */ if (argc || devno_args) log_verbose("Scanning devices on command line."); while (argc--) { pv_name = *argv++; if (pv_name[0] == '/') { if (!(dev = dev_cache_get(pv_name, cmd->lvmetad_filter))) { /* Remove device path from lvmetad. */ log_debug("Removing dev %s from lvmetad cache.", pv_name); if ((dev = dev_cache_get(pv_name, NULL))) { if (!_lvmetad_clear_dev(dev->dev, MAJOR(dev->dev), MINOR(dev->dev))) remove_errors++; } else { log_error("Physical Volume %s not found.", pv_name); ret = ECMD_FAILED; } } else { /* Add device path to lvmetad. */ log_debug("Scanning dev %s for lvmetad cache.", pv_name); if (!lvmetad_pvscan_single(cmd, dev, &found_vgnames, &pp.changed_vgnames)) add_errors++; } } else { if (sscanf(pv_name, "%d:%d", &major, &minor) != 2) { log_warn("WARNING: Failed to parse major:minor from %s, skipping.", pv_name); continue; } devno = MKDEV((dev_t)major, (dev_t)minor); if (!(dev = dev_cache_get_by_devt(devno, cmd->lvmetad_filter))) { /* Remove major:minor from lvmetad. */ log_debug("Removing dev %d:%d from lvmetad cache.", major, minor); if (!_lvmetad_clear_dev(devno, major, minor)) remove_errors++; } else { /* Add major:minor to lvmetad. */ log_debug("Scanning dev %d:%d for lvmetad cache.", major, minor); if (!lvmetad_pvscan_single(cmd, dev, &found_vgnames, &pp.changed_vgnames)) add_errors++; } } if (sigint_caught()) { ret = ECMD_FAILED; goto_out; } } if (!devno_args) goto activate; /* Process any grouped --major --minor args */ dm_list_iterate_items(current_group, &cmd->arg_value_groups) { major = grouped_arg_int_value(current_group->arg_values, major_ARG, major); minor = grouped_arg_int_value(current_group->arg_values, minor_ARG, minor); if (major < 0 || minor < 0) continue; devno = MKDEV((dev_t)major, (dev_t)minor); if (!(dev = dev_cache_get_by_devt(devno, cmd->lvmetad_filter))) { /* Remove major:minor from lvmetad. */ log_debug("Removing dev %d:%d from lvmetad cache.", major, minor); if (!_lvmetad_clear_dev(devno, major, minor)) remove_errors++; } else { /* Add major:minor to lvmetad. */ log_debug("Scanning dev %d:%d for lvmetad cache.", major, minor); if (!lvmetad_pvscan_single(cmd, dev, &found_vgnames, &pp.changed_vgnames)) add_errors++; } if (sigint_caught()) { ret = ECMD_FAILED; goto_out; } } /* * In the process of scanning devices, lvmetad may have become * disabled. If so, revert to scanning for the autoactivation step. * Only autoactivate the VGs that were found during the dev scans. */ if (lvmetad_used() && lvmetad_is_disabled(cmd, &reason)) { log_warn("WARNING: Not using lvmetad because %s.", reason); lvmetad_make_unused(cmd); } activate: /* * Step 2: when the PV was sent to lvmetad, the lvmetad reply * indicated if all the PVs for the VG are now found. If so, * the vgname was added to the list, and we can attempt to * autoactivate LVs in the VG. */ if (do_activate) ret = _pvscan_autoactivate(cmd, &pp, all_vgs, &found_vgnames); out: if (remove_errors || add_errors || pp.activate_errors) ret = ECMD_FAILED; if (!sync_local_dev_names(cmd)) stack; unlock_vg(cmd, NULL, VG_GLOBAL); return ret; } /* * Three main pvscan cases related to lvmetad usage: * 1. pvscan * 2. pvscan --cache * 3. pvscan --cache * * 1. The 'pvscan' command (without --cache) may or may not attempt to * repopulate the lvmetad cache, and may or may not use the lvmetad * cache to display PV info: * * i. If lvmetad is being used and is in a normal state, then 'pvscan' * will simply read and display PV info from the lvmetad cache. * * ii. If lvmetad is not being used, 'pvscan' will read all devices to * display the PV info. * * iii. If lvmetad is being used, but has been disabled (because of * duplicate devs or lvm1 metadata), or has a non-matching token * (because the device filter is different from the device filter last * used to populate lvmetad), then 'pvscan' will begin by rescanning * devices to repopulate lvmetad. If lvmetad is enabled after the * rescan, then 'pvscan' will simply read and display PV info from the * lvmetad cache (like case i). If lvmetad is disabled after the * rescan, then 'pvscan' will read all devices to display PV info * (like case ii). * * 2. The 'pvscan --cache' command (without named devs) will always * attempt to repopulate the lvmetad cache by rescanning all devs * (regardless of whether lvmetad was previously disabled or had an * unmatching token.) lvmetad may be enabled or disabled after the * rescan (depending on whether duplicate devs or lvm1 metadata was * found). * * 3. The 'pvscan --cache ' command will attempt to repopulate the * lvmetad cache by rescanning all devs if lvmetad has a non-matching * token (e.g. because it has not yet been populated, see FIXME above). * Otherwise, the command will only rescan the named and send * their metadata to lvmetad. */ int pvscan(struct cmd_context *cmd, int argc, char **argv) { struct pvscan_params params = { 0 }; struct processing_handle *handle = NULL; const char *reason = NULL; int ret; if (arg_is_set(cmd, cache_long_ARG)) return _pvscan_cache(cmd, argc, argv); if (argc) { log_error("Too many parameters on command line."); return EINVALID_CMD_LINE; } if (arg_is_set(cmd, activate_ARG)) { log_error("--activate is only valid with --cache."); return EINVALID_CMD_LINE; } if (arg_is_set(cmd, major_ARG) || arg_is_set(cmd, minor_ARG)) { log_error("--major and --minor are only valid with --cache."); return EINVALID_CMD_LINE; } if (arg_is_set(cmd, novolumegroup_ARG) && arg_is_set(cmd, exported_ARG)) { log_error("Options -e and -n are incompatible"); return EINVALID_CMD_LINE; } if (arg_is_set(cmd, exported_ARG) || arg_is_set(cmd, novolumegroup_ARG)) log_warn("WARNING: only considering physical volumes %s", arg_is_set(cmd, exported_ARG) ? "of exported volume group(s)" : "in no volume group"); /* Needed because this command has NO_LVMETAD_AUTOSCAN. */ if (lvmetad_used() && (!lvmetad_token_matches(cmd) || lvmetad_is_disabled(cmd, &reason))) { if (lvmetad_used() && !lvmetad_pvscan_all_devs(cmd, 0)) { log_warn("WARNING: Not using lvmetad because cache update failed."); lvmetad_make_unused(cmd); } if (lvmetad_used() && lvmetad_is_disabled(cmd, &reason)) { log_warn("WARNING: Not using lvmetad because %s.", reason); lvmetad_make_unused(cmd); } } if (!lock_vol(cmd, VG_GLOBAL, LCK_VG_WRITE, NULL)) { log_error("Unable to obtain global lock."); return ECMD_FAILED; } if (!(handle = init_processing_handle(cmd, NULL))) { log_error("Failed to initialize processing handle."); ret = ECMD_FAILED; goto out; } handle->custom_handle = ¶ms; ret = process_each_pv(cmd, argc, argv, NULL, 0, 0, handle, _pvscan_single); if (!params.pvs_found) log_print_unless_silent("No matching physical volumes found"); else log_print_unless_silent("Total: %d [%s] / in use: %d [%s] / in no VG: %d [%s]", params.pvs_found, display_size(cmd, params.size_total), params.pvs_found - params.new_pvs_found, display_size(cmd, (params.size_total - params.size_new)), params.new_pvs_found, display_size(cmd, params.size_new)); out: unlock_vg(cmd, NULL, VG_GLOBAL); destroy_processing_handle(cmd, handle); return ret; }